Science.gov

Sample records for arch equilibrium estabilidade

  1. Siphon flows in isolated magnetic flux tubes. 3: The equilibrium path of the flux tube arch

    NASA Technical Reports Server (NTRS)

    Thomas, John H.; Montesinis, Benjamin

    1989-01-01

    The arched equilibrium path of a thin magnetic flux tube in a plane-stratified, nonmagnetic atmosphere is calculated for cases in which the flux tube contains a steady siphon flow. The large scale mechanical equilibrium of the flux tube involves a balance among the magnetic buoyancy force, the net magnetic tension force due to the curvature of the flux tube axis, and the inertial (centrifugal) force due to the siphon flow along curved streamlines. The ends of the flux tube are assumed to be pinned down by some other external force. Both isothermal and adiabatic siphon flows are considered for flux tubes in an isothermal external atmosphere. For the isothermal case, in the absence of a siphon flow the equilibrium path reduces to the static arch calculated by Parker (1975, 1979). The presence of a siphon flow causes the flux tube arch to bend more sharply, so that magnetic tension can overcome the additional straightening effect of the inertial force, and reduces the maximum width of the arch. The curvature of the arch increases as the siphon flow speed increases. For a critical siphon flow, with supercritical flow in the downstream leg, the arch is asymmetric, with greater curvature in the downstream leg of the arch. Adiabatic flow have qualitatively similar effects, except that adiabatic cooling reduces the buoyancy of the flux tube and thus leads to significantly wider arches. In some cases the cooling is strong enough to create negative buoyancy along sections of the flux tube, requiring upward curvature of the flux tube path along these sections and sometimes leading to unusual equilibrium paths of periodic, sinusoidal form.

  2. Siphon flows in isolated magnetic flux tubes. 3: The equilibrium path of the flux tube arch

    NASA Astrophysics Data System (ADS)

    Thomas, John H.; Montesinis, Benjamin

    1989-09-01

    The arched equilibrium path of a thin magnetic flux tube in a plane-stratified, nonmagnetic atmosphere is calculated for cases in which the flux tube contains a steady siphon flow. The large scale mechanical equilibrium of the flux tube involves a balance among the magnetic buoyancy force, the net magnetic tension force due to the curvature of the flux tube axis, and the inertial (centrifugal) force due to the siphon flow along curved streamlines. The ends of the flux tube are assumed to be pinned down by some other external force. Both isothermal and adiabatic siphon flows are considered for flux tubes in an isothermal external atmosphere. For the isothermal case, in the absence of a siphon flow the equilibrium path reduces to the static arch calculated by Parker (1975, 1979). The presence of a siphon flow causes the flux tube arch to bend more sharply, so that magnetic tension can overcome the additional straightening effect of the inertial force, and reduces the maximum width of the arch. The curvature of the arch increases as the siphon flow speed increases. For a critical siphon flow, with supercritical flow in the downstream leg, the arch is asymmetric, with greater curvature in the downstream leg of the arch. Adiabatic flow have qualitatively similar effects, except that adiabatic cooling reduces the buoyancy of the flux tube and thus leads to significantly wider arches. In some cases the cooling is strong enough to create negative buoyancy along sections of the flux tube, requiring upward curvature of the flux tube path along these sections and sometimes leading to unusual equilibrium paths of periodic, sinusoidal form.

  3. High arch

    MedlinePlus

    ... condition can make it difficult to fit into shoes. People who have high arches most often need ... Symptoms include: Shortened foot length Difficulty fitting shoes Foot pain with walking, standing, and running (not everyone has this symptom)

  4. Solar Arches

    NASA Image and Video Library

    2017-09-28

    The magnetic field lines between a pair of active regions formed a beautiful set of swaying arches, seen in this footage captured by NASA’s Solar Dynamics Observatory on April 24-26, 2017. The arches are traced out by charged particles spinning along the magnetic field lines. These arches, which form a connection between regions of opposite magnetic polarity, are visible in exquisite detail in this wavelength of extreme ultraviolet light. Extreme ultraviolet light is typically invisible to our eyes, but is colorized here in gold. Read more: go.nasa.gov/2pGgYZt NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

  5. ArchE - An Architecture Design Assistant

    DTIC Science & Technology

    2016-06-30

    X, Module X 3 Author / Presenter, Date if Needed What is ArchE? ArchE is a software architecture design assistant, which: • Takes quality and...functional requirements as input • Elicits key quality attribute information to refine quality requirements • Elicits key architectural information...Derives candidate architectures • Evaluates whether quality requirements are satisfied • Identifies tradeoffs • Suggests alternative architectures ArchE is

  6. Towering Arches

    NASA Image and Video Library

    2016-04-06

    This still image from an animation from NASA GSFC Solar Dynamics Observatory shows arches of magnetic field lines towered over the edge of the Sun as a pair of active regions began to rotate into view Apr. 5-6, 2016.

  7. Organized Arches

    NASA Image and Video Library

    2017-01-17

    Magnetic arcs of plasma that spiraled above two active regions held their shape fairly well over 18 hours (Jan. 11-12, 2017). The charged plasma is being controlled the magnetic field lines of the active regions. The field lines become clearly visible when viewed in this wavelength of extreme ultraviolet light. Often the arches bend and twist more dynamically than the relatively stable ones seen here. Movies are available at http://photojournal.jpl.nasa.gov/catalog/PIA12327

  8. Dental arch asymmetry

    PubMed Central

    Al-Zubair, Nabil Muhsen

    2014-01-01

    Objective: This study was conducted to assess the dental arch asymmetry in a Yemeni sample aged (18-25) years. Materials and Methods: The investigation involved clinical examination of 1479 adults; only 253 (129 females, 124 males) out of the total sample were selected to fulfill the criteria for the study sample. Study models were constructed and evaluated to measure mandibular arch dimensions. Three linear distances were utilized on each side on the dental arch: Incisal-canine distance, canine-molar distance and incisal-molar distance, which represent the dental arch segmental measurements. Results: When applying “t-test” at P < 0.05, no significant differences were found between the right and left canine-molar, incisal-canine and incisal-molar distances in both dental arches for both sexes. The greater variation (0.30 mm) was observed between right and left canine-molar distance in the maxillary dental arch in male and the smaller (0.04 mm) in the mandibular dental arch between the right and left canine-molar distance in females. Conclusion: The findings of the present study revealed a symmetrical pattern of dental arches, since the right and left sides showed no statistically significant difference. In general, it can be observed that the measurements related to the central incisors and canines have the widest range of reading and give the impression that the location of central incisor and canines to each other and to other teeth is the strongest factor in determining the dental arch asymmetry. PMID:24966774

  9. Arching Solar Prominence

    NASA Image and Video Library

    NASA’s STEREO (Ahead) spacecraft watched as an eruptive prominence rose up and arched out in a horseshoe shape far above the Sun’s surface (Aug. 25, 2010). The image and movie show the action in a...

  10. Intraoral gothic arch tracing.

    PubMed

    Rubel, Barry; Hill, Edward E

    2011-01-01

    In order to create optimum esthetics, function and phonetics in complete denture fabrication, it is necessary to record accurate maxillo-mandibular determinants of occlusion. This requires clinical skill to establish an accurate, verifiable and reproducible vertical dimension of occlusion (VDO) and centric relation (CR). Correct vertical relation depends upon a consideration of several factors, including muscle tone, inter-dental arch space and parallelism of the ridges. Any errors made while taking maxillo-mandibular jaw relation records will result in dentures that are uncomfortable and, possibly, unwearable. The application of a tracing mechanism such as the Gothic arch tracer (a central bearing device) is a demonstrable method of determining centric relation. Intraoral Gothic arch tracers provide the advantage of capturing VDO and CR in an easy-to-use technique for practitioners. Intraoral tracing (Gothic arch tracing) is a preferred method of obtaining consistent positions of the mandible in motion (retrusive, protrusive and lateral) at a comfortable VDO.

  11. Dental arch analysis system.

    PubMed

    Mutinelli, Sabrina; Cozzani, Mauro; Manfredi, Mario; Siciliani, Giuseppe

    2004-01-01

    The purpose of our research is to describe a computerized method, which enables orthodontists and researchers to analyze variation of dental arch form and dimension. The analysis system is composed of two independent parts: the database, where the images of scanned dental casts are stored, and the software. The operator uses the software to identify some landmarks on dental cast images. Corresponding distances are calculated (interincisive, intercanine and intermolar widths and the curve axis). Then the software algorithms calculate and draw the curves passing trough the selected landmarks (conics, catenary, cubic spline and polynomial curves). In the chosen curves the arch length is measured. The dental cast data, recorded at different times of the subject's life or in different steps of orthodontic treatment, are compared in order to evaluate the change in dimension (arch length and width) and form (shape). The statistical analysis of the data evaluates the variation in form and in dimension separately. The shape change is defined by Euclidean Distance Matrix Analysis (EDMA) and Bootstrap analysis. The computerized method allows orthodontists and researches to evaluate the variation in dimension and form of the dental arch in un-treated subjects and-or orthodontic patients over time. After the analysis of a large sample of patients or subjects, information concerning changes in dental arch dimension and form can be added to previous studies of other authors, distinguishing variation during and after orthodontic treatment, during growth or aging.

  12. 9. DETAIL OF EAST ARCH, FROM ROADWAY, SHOWING ARCH RIB, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. DETAIL OF EAST ARCH, FROM ROADWAY, SHOWING ARCH RIB, ARTICULATED HANGER AND GUARDRAIL. VIEW TO SOUTHEAST. - Rock Valley Bridge, Spanning North Timber Creek at Old U.S. Highway 30, Marshalltown, Marshall County, IA

  13. 10. DETAIL OF WEST ARCH, FROM ROADWAY, SHOWING ARCH RIB, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. DETAIL OF WEST ARCH, FROM ROADWAY, SHOWING ARCH RIB, HANGERS AND GUARDRAIL. VIEW TO SOUTH. - Rock Valley Bridge, Spanning North Timber Creek at Old U.S. Highway 30, Marshalltown, Marshall County, IA

  14. BRIDGE ABUTMENTS WITH ARCH SEGMENTS ON RIVER BOTTOM. ARCHES COLLAPSED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    BRIDGE ABUTMENTS WITH ARCH SEGMENTS ON RIVER BOTTOM. ARCHES COLLAPSED AROUND EIGHT YEARS BEFORE THIS DATE. - Whittlesey Road Bridge, Spanning Black River at Whittlesey Road, Lyons Falls, Lewis County, NY

  15. A Golden Arch

    NASA Image and Video Library

    2015-08-06

    This still image from an animation from NASA GSFC Solar Dynamics Observatory shows magnetically charged particles forming a nicely symmetrical arch at the edge of the Sun as they followed the magnetic field lines of an active region Aug.4-5, 2015. Before long the arch begins to fade, but a fainter and taller arch appears for a time in the same place. Note that several other bright active regions display similar kinds of loops above them. These images of ionized iron at about one million degrees were taken in a wavelength of extreme ultraviolet light. The video covers about 30 hours of activity. http://photojournal.jpl.nasa.gov/catalog/PIA19874

  16. Magnetic Field Arches

    NASA Image and Video Library

    2016-09-28

    When an active region rotated into a profile view, SDO was able to capture the magnificent loops arching above an active region (Sept. 28-29, 2016). Active region are areas of strong magnetic fields. The magnetic field lines above these regions are illuminated by charged particles spiraling along them. The images were taken in a wavelength of extreme ultraviolet light. The video covers 12 hours of activity. The Earth was inset to give a sense of the scale of these towering arches. Movies are available at http://photojournal.jpl.nasa.gov/catalog/PIA21101

  17. Dental Arch Wire

    NASA Technical Reports Server (NTRS)

    1979-01-01

    Straightening teeth is an arduous process requiring months, often years, of applying corrective pressure by means of arch wires-better known as brace-which may have to be changed several times in the course of treatment. A new method has been developed by Dr. George Andreasen, orthodontist and dental scientist at the University of Iowa. The key is a new type of arch wire material, called Nitinol, with exceptional elasticity which helps reduce the required number of brace changes. An alloy of nickel and titanium, Nitinol was originally developed for aerospace applications by the Naval Ordnance Laboratory, now the Naval Surface Weapons Laboratory, White Oaks, Maryland. NASA subsequently conducted additional research on the properties of Nitinol and on procedures for processing the metal.

  18. The ARCHES Project

    NASA Astrophysics Data System (ADS)

    Motch, C.; Arches Consortium

    2015-09-01

    The Astronomical Resource Cross-matching for High Energy Studies (ARCHES) project is a FP7-Space funded programme started in 2013 and involving the Observatoire Astronomique de Strasbourg including the CDS (France), the Leibniz- Institut für Astrophysik Potsdam (Germany), the University of Leicester (UK), the Universidad de Cantabria (IFCA, Spain) and the Instituto Nacional de Tecnica Aeroespacial (Spain). ARCHES will provide the international astronomical community with well-characterised multi-wavelength data in the form of spectral energy distributions (SEDs) for large samples of objects extracted from the 3XMM X-ray catalogue of serendipitous sources. The project develops new tools implementing fully probabilistic simultaneous cross-correlation of several catalogues and a multi-wavelength finder for clusters of galaxies. SEDs are based on an enhanced version of the 3XMM catalogue and on a careful selection of the most relevant multi-wavelength archival catalogues. In order to ensure the largest audience, SEDs will be distributed to the international community through CDS services and through the Virtual Observatory. These enhanced resources are tested in the framework of several science cases. More information may be found at http://www.arches-fp7.eu/

  19. Double arch mirror study

    NASA Technical Reports Server (NTRS)

    Vukobratovich, D.; Hillman, D.

    1983-01-01

    The development of a method of mounting light weight glass mirrors for astronomical telescopes compatible with the goals of the Shuttle Infrared Telescope Facility (SIRTF) was investigated. A 20 in. diameter double arch lightweight mirror previously fabricated was modified to use a new mount configuration. This mount concept was developed and fabricated. The mounting concept of the double mounting mirror is outlined. The modifications made to the mirror, fabrication of the mirror mount, and room temperature testing of the mirror and mount and the extension of the mirror and mount concept to a full size (40 in. diameter) primary mirror for SIRTF are discussed.

  20. Solar Golden Arches

    NASA Image and Video Library

    2017-05-01

    The magnetic field lines between a pair of active regions formed a beautiful set of swaying arches rising up above them Apr. 24-26, 2017, as seen by NASA Solar Dynamics Observatory. The connection between opposing poles of polarity is visible in exquisite detail in this wavelength of extreme ultraviolet light. What we are really seeing are charged particles spinning along the magnetic field lines. Other field lines are traced as they reach out in other directions as well. Videos can be seen at https://photojournal.jpl.nasa.gov/catalog/PIA21604

  1. 35. ALTERNATE DESIGN USING THROUGH ARCH SPANS, WITH ARCH REPEATED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    35. ALTERNATE DESIGN USING THROUGH ARCH SPANS, WITH ARCH REPEATED BETWEEN TOWER LEGS, AND ASHLAR MASONRY WALLS AND PYLONS Pen-and-ink drawing by project architect Alfred Eichler, 1934. - Sacramento River Bridge, Spanning Sacramento River at California State Highway 275, Sacramento, Sacramento County, CA

  2. The ARCHES project

    NASA Astrophysics Data System (ADS)

    Motch, C.; Arches Consortium

    2014-07-01

    ARCHES (Astronomical Resource Cross-matching for High Energy Studies) is a FP7-Space funded project started in 2013 and involving the Observatoire Astronomique de Strasbourg including the CDS (France), the Leibniz-Institut fuer Astrophysik Potsdam (Germany), the University of Leicester (UK), the Universidad de Cantabria (IFCA, Spain) and the Instituto Nacional de Técnica Aeroespacial (Madrid, Spain). ARCHES aims at providing the international astronomical community with well-characterised multi-wavelength data in the form of spectral energy distributions (SEDs) for large sets of objects extracted from the 3XMM catalogue. The project develops new tools implementing fully probabilistic simultaneous cross-correlation of several catalogues. SEDs are based on an enhanced version of the 3XMM catalogue and on a careful selection of the most relevant multi-wavelength archival catalogues. In order to ensure the largest audience, SEDs will be distributed to the international community through CDS services and through the Virtual Observatory. These enhanced resources are currently tested in the framework of several science cases. An integrated cluster finder is developed at Potsdam, AGN science is studied at Leicester and IFCA while populations of Galactic X-ray sources are investigated at Strasbourg and Madrid.

  3. [Double aortic arch with dominant left arch: case report].

    PubMed

    Ece, Ibrahim; Paç, Feyza Ayşenur; Paç, Mustafa; Ballı, Sevket

    2012-09-01

    A vascular ring is defined as an anomaly of the great arteries (aortic arch and its branches) that compresses the trachea or esophagus. Double aortic arch is the most common vascular ring. Double aortic arch is very rare and typically becomes symptomatic in infancy or early childhood. We present a 7-year-old girl admitted to our clinic for evaluation of recurrent respiratory infection with dysphagia. Double aortic arch was suspected from echocardiography and diagnosed with cardiac computed tomography. Left aortic arcus was larger than the right at computed tomography and cardiac catheterisation. After surgery the symptoms improved strikingly. We conclude that vascular ring should be considered in the patients presenting with recurrent pulmonary infections and dysphagia. Early diagnosis and treatment may prevent chronic, irreversible complications.

  4. Modeling Outcomes: Modified Aortic Arch Advancement for Neonatal Hypoplastic Arch.

    PubMed

    Nellis, Joseph R; Chung, Timothy K; Agarwal, Nandita; Torres, Jose E; Holgren, Sarah E; Raghavan, Madhavan L; Turek, Joseph W

    Numerous surgical approaches regarding aortic arch advancement for neonatal arch hypoplasia have been described. These repairs can be classified into two categories: those that incorporate a patch and those that do not. The decision between repairs remains largely experiential, rather than empirical, because of the limited number of reported outcomes. We report early outcomes from neonates undergoing modified aortic arch advancement with an anterior patch and our experience using computational fluid dynamic modeling to better understand the hemodynamic consequences associated with this repair. A retrospective review of neonates undergoing aortic arch advancement with anterior patch in 2014 at a single institution was performed. Anatomical, perioperative, and follow-up data were collected. Three-dimensional cardiac magnetic resonance images were used to generate computational fluid dynamic models of the modified anterior patch and direct end-to-side repairs. Cardiac waveform inputs were simulated and hemodynamic analyzed. Ten neonates underwent modified aortic arch advancement. No hemodynamically significant gradients were observed at a median follow-up of 0.77 (0.30-1.2) years. Asymmetrical flow was observed in the end-to-side repair, whereas more concentric laminar flow was observed throughout the modified model. Spatial variations in velocities immediately distal to the anastomosis were greater in the end-to-side model (0.35 vs 0.17 m/s, P < 0.001). Time-averaged variations in wall shear stress during systole were greater in the end-to-side model at the same location (3.44 vs 1.98 dynes/cm, P < 0.001). Early outcomes after the use of an anterior patch for neonatal hypoplastic aortic arch repair show favorable hemodynamic outcomes.

  5. Pseudoaneurysm of the aortic arch

    PubMed Central

    Lu, Yuan-Qiang; Yao, Feng; Shang, An-Dong; Pan, Jian

    2016-01-01

    Abstract Background: Pseudoaneurysm of the aortic arch is uncommonly associated with cancer, and is extremely rare in pulmonary cancer. Here, we report an unusual and successfully treated case of aortic arch pseudoaneurysm in a male patient with lung squamous cell carcinoma. Methods: A 64-year-old male patient was admitted to the Emergency Department, presenting with massive hemoptysis (>500 mL blood during the 12 hours prior to treatment). The diagnosis of aortic arch pseudoaneurysm was confirmed after inspection of computed tomographic angiography and three-dimensional reconstruction. We processed the immediate endovascular stent-grafting for this patient. Results: This patient recovered with no filling or enlargement of the pseudoaneurysm, no episodes of hemoptysis, and no neurological complications during the 4-week follow-up period. Conclusion: Herein, we compare our case with other cancer-related pseudoaneurysms in the medical literature and summarize the clinical features and treatment of this unusual case. PMID:27495079

  6. Simple Way of Recording Dental Arch Forms

    PubMed Central

    Ratre, Ram Kishore; Jain, Sandhya; Chandki, Rita

    2015-01-01

    Like finger prints each individual has a unique dental arch form design. Recording patient’s dental arch form may be required in various fields in dentistry be it longitudinal studies for evaluating growth, forensic dentistry and most importantly in orthodontic practice for fabricating arch wires for individual patients. An easy and practical method to obtain individual arch form for each patient is explained. PMID:25954726

  7. The Algebra of the Arches

    ERIC Educational Resources Information Center

    Buerman, Margaret

    2007-01-01

    Finding real-world examples for middle school algebra classes can be difficult but not impossible. As we strive to accomplish teaching our students how to solve and graph equations, we neglect to teach the big ideas of algebra. One of those big ideas is functions. This article gives three examples of functions that are found in Arches National…

  8. Arch Reconstruction with Autologous Pulmonary Artery Patch in Interrupted Aortic Arch

    PubMed Central

    Lee, Won-Young

    2014-01-01

    Various surgical techniques have been developed for the repair of an interrupted aortic arch. However, tension and Gothic arch formation at the anastomotic site have remained major problems for these techniques: Excessive tension causes arch stenosis and left main bronchus compression, and Gothic arch configuration is related to cardiovascular complications. To resolve these problems, we adopted a modified surgical technique of distal aortic arch augmentation using an autologous main pulmonary artery patch. The descending aorta was then anastomosed to the augmented aortic arch in an end-to-side manner. Here, we report two cases of interrupted aortic arch that were repaired using this technique. PMID:24782962

  9. Aortic Arch Interruption and Persistent Fifth Aortic Arch in Phace Syndrome: Prenatal Diagnosis and Postnatal Course.

    PubMed

    Chiappa, Enrico; Greco, Antonella; Fainardi, Valentina; Passantino, Silvia; Serranti, Daniele; Favilli, Silvia

    2015-09-01

    PHACE is a rare congenital neurocutaneous syndrome where posterior fossa malformations, hemangiomas, cerebrovascular anomalies, aortic arch anomalies, cardiac defects, and eye abnormalities are variably associated. We describe the prenatal detection and the postnatal course of a child with PHACE syndrome with a unique type of aortic arch anomaly consisting of proximal interruption of the aortic arch and persistence of the fifth aortic arch. The fifth aortic arch represented in this case a vital systemic-to-systemic connection between the ascending aorta and the transverse portion of the aortic arch allowing adequate forward flow through the aortic arch without surgical treatment.

  10. Arch reconstruction with autologous pulmonary artery patch in interrupted aortic arch.

    PubMed

    Lee, Won-Young; Park, Jeong-Jun

    2014-04-01

    Various surgical techniques have been developed for the repair of an interrupted aortic arch. However, tension and Gothic arch formation at the anastomotic site have remained major problems for these techniques: Excessive tension causes arch stenosis and left main bronchus compression, and Gothic arch configuration is related to cardiovascular complications. To resolve these problems, we adopted a modified surgical technique of distal aortic arch augmentation using an autologous main pulmonary artery patch. The descending aorta was then anastomosed to the augmented aortic arch in an end-to-side manner. Here, we report two cases of interrupted aortic arch that were repaired using this technique.

  11. Partition Equilibrium

    NASA Astrophysics Data System (ADS)

    Feldman, Michal; Tennenholtz, Moshe

    We introduce partition equilibrium and study its existence in resource selection games (RSG). In partition equilibrium the agents are partitioned into coalitions, and only deviations by the prescribed coalitions are considered. This is in difference to the classical concept of strong equilibrium according to which any subset of the agents may deviate. In resource selection games, each agent selects a resource from a set of resources, and its payoff is an increasing (or non-decreasing) function of the number of agents selecting its resource. While it has been shown that strong equilibrium exists in resource selection games, these games do not possess super-strong equilibrium, in which a fruitful deviation benefits at least one deviator without hurting any other deviator, even in the case of two identical resources with increasing cost functions. Similarly, strong equilibrium does not exist for that restricted two identical resources setting when the game is played repeatedly. We prove that for any given partition there exists a super-strong equilibrium for resource selection games of identical resources with increasing cost functions; we also show similar existence results for a variety of other classes of resource selection games. For the case of repeated games we identify partitions that guarantee the existence of strong equilibrium. Together, our work introduces a natural concept, which turns out to lead to positive and applicable results in one of the basic domains studied in the literature.

  12. El problema de estabilidad de los sistemas Hamiltonianos multidimensionales

    NASA Astrophysics Data System (ADS)

    Cincotta, P. M.

    Se revisarán los aspectos básicos del problema de estabilidad de sistemans Hamiltonianos N-dimensionales, haciendo especial énfasis en los posibles mecanismos que dan lugar a la aparición de ``caos": overlap de resonancias, difusión de Arnol'd y otros procesos difusivos alternativos. Se mencionarán los aspectos aún no resueltos sobre la estabilidad de los sistemas con N > 2. Finalmente, se discutirá cuáles de estos mecanismos podrían tener alguna relevancia en la dinámica de sistemas estelares y planetarios.

  13. The ARCHES Integrated Cluster Finder

    NASA Astrophysics Data System (ADS)

    Mints, A.; Schwope, A.

    2014-07-01

    We are developing a tool to search for galaxy clusters associated with X-ray sources from the 3XMM catalog within the ARCHES project (Astronomical Resource cross-matching for High-Energy Studies). We make use of the new cross-matching tool developed for ARCHES to select galaxies in different catalogs around X-ray positions and then try to find clusters by searching for overdensities in the multi-color space. Colors are related to redshifts using spectroscopic data for passively evolving galaxies from the BOSS and VIPERS catalogs. So far we are making use of SDSS, UKIDSS, WISE, and CFHTLS photometric catalogs, but the method can easily be expanded to other data as well (e.g. Pan-STARRS and DES). We present test results of our tool performed on reference samples from the XMM/SDSS cluster survey (Takey et al 2012) and the NORAS/REFLEX surveys.

  14. Complete arch implant impression technique.

    PubMed

    Ma, Junping; Rubenstein, Jeffrey E

    2012-06-01

    When making a definitive impression for an arch containing multiple implants, there are many reported techniques for splinting impression copings. This article introduces a splint technique that uses the shim method, which has been demonstrated to reduce laboratory and patient chair time, the number of impression copings and laboratory analogs needed, and the ultimate cost. Copyright © 2012 The Editorial Council of the Journal of Prosthetic Dentistry. Published by Mosby, Inc. All rights reserved.

  15. The Biomechanics of Zygomatic Arch Shape.

    PubMed

    Smith, Amanda L; Grosse, Ian R

    2016-12-01

    Mammalian zygomatic arch shape is remarkably variable, ranging from nearly cylindrical to blade-like in cross section. Based on geometry, the arch can be hypothesized to be a sub-structural beam whose ability to resist deformation is related to cross sectional shape. We expect zygomatic arches with different cross sectional shapes to vary in the degree to which they resist local bending and torsion due to the contraction of the masseter muscle. A stiffer arch may lead to an increase in the relative proportion of applied muscle load being transmitted through the arch to other cranial regions, resulting in elevated cranial stress (and thus, strain). Here, we examine the mechanics of the zygomatic arch using a series of finite element modeling experiments in which the cross section of the arch of Pan troglodytes has been modified to conform to idealized shapes (cylindrical, elliptical, blade-like). We find that the shape of the zygomatic arch has local effects on stain that do not conform to beam theory. One exception is that possessing a blade-like arch leads to elevated strains at the postorbital zygomatic junction and just below the orbits. Furthermore, although modeling the arch as solid cortical bone did not have the effect of elevating strains in other parts of the face, as had been expected, it does have a small effect on stress associated with masseter contraction. These results are counterintuitive. Even though the arch has simple beam-like geometry, we fail to find a simple mechanical explanation for the diversity of arch shape. Anat Rec, 299:1734-1752, 2016. © 2016 Wiley Periodicals, Inc.

  16. Revisiting impressions using dual-arch trays.

    PubMed

    Small, Bruce W

    2012-01-01

    Making routine perfect impressions is the goal of any restorative dentist. Using dual-arch trays is an easy, repeatable way to accomplish that goal, as long as each step is done before the next and each step is performed perfectly. This column reviewed several articles that support the metal dual-arch concept and provided some clinical tips that might help restorative dentists. The dual-arch technique does have its limits and is meant for one or two teeth in a quadrant when there are other teeth to occlude with. Also, if the case involves anterior guidance, a full-arch impression maybe advisable.

  17. Arch mineral pursues multiple dipping seams

    SciTech Connect

    Sprouls, M.W.

    1981-07-01

    Arch Mineral's three Hanna Basin mines in Carbon County, WY, recover about eight million tpy from more than a dozen coal seams. Arch's experience has proven stripping techniques for dipping seams, and has revealed better methods for recontouring and revegetating mined land.

  18. Techniques for aortic arch endovascular repair.

    PubMed

    Hongku, Kiattisak; Dias, Nuno; Sonesson, Bjorn; Resch, Timothy

    2016-06-01

    This article reviews endovascular strategies for aortic arch repair. Open repair remains the gold standard particularly for good risk patients. Endovascular treatment potentially offers a less invasive repair. Principles, technical considerations, devices and outcomes of each technique are discussed and summarized. Hybrid repair combines less invasive revascularization options, instead of arch replacement while extending stent-graft into the arch. Outcomes vary with regard to extent of repair and aortic arch pathologies treated. Results of arch chimney and other parallel graft techniques perhaps make it a less preferable choice for elective cases. However, they are very appealing options for urgent or bailout situations. Fenestrated stent-grafting is subjected to many technical challenges in aortic arch due to difficulties in stent-graft orientation and fenestration positioning. In situ fenestration techniques emerge to avoid these problems, but durability of stent-grafts after fenestration and ischemic consequences of temporary carotid arteries coverage raises some concern total arch repair using this technique. Arch branched graft is a new technology. Early outcomes did not meet the expectation; however the results have been improving after its learning curve period. Refining stent-graft technologies and implantation techniques positively impact outcomes of endovascular approaches.

  19. Maxillary and mandibular anterior crown width/height ratio and its relation to various arch perimeters, arch length, and arch width groups

    PubMed Central

    Shahid, Fazal; Alam, Mohammad Khursheed; Khamis, Mohd Fadhli

    2015-01-01

    Objective: To investigate the maxillary and mandibular anterior crown width/height ratio and its relation to various arch perimeters, arch length, and arch width (intercanine, interpremolar, and intermolar) groups. Materials and Methods: The calculated sample size was 128 subjects. The crown width/height, arch length, arch perimeter, and arch width of the maxilla and mandible were obtained via digital calliper (Mitutoyo, Japan). A total of 4325 variables were measured. The sex differences in the crown width and height were evaluated. Analysis of variance was applied to evaluate the differences between arch length, arch perimeter, and arch width groups. Results: Males had significantly larger mean values for crown width and height than females (P ≤ 0.05) for maxillary and mandibular arches, both. There were no significant differences observed for the crown width/height ratio in various arch length, arch perimeter, and arch width (intercanine, interpremolar, and intermolar) groups (P ≤ 0.05) in maxilla and mandible, both. Conclusions: Our results indicate sexual disparities in the crown width and height. Crown width and height has no significant relation to various arch length, arch perimeter, and arch width groups of maxilla and mandible. Thus, it may be helpful for orthodontic and prosthodontic case investigations and comprehensive management. PMID:26929686

  20. Determinant factors of Yemeni maxillary arch dimensions.

    PubMed

    Al-Zubair, Nabil Muhsen

    2015-01-01

    Information about maxillary arch and palatal dimensions in human populations is important for clinical orthodontics. This study was conducted to assess the determinants of maxillary arch dimensions in a sample of Yemeni individuals aged 18-25 years. The study sample comprised 214/765 adults (101 women, 113 men) who underwent clinical examination and fulfilled the study criteria. Study models were constructed and evaluated to measure maxillary arch and palatal dimensions. The majority of mean maxillary arch dimensions were significantly greater in men than in women, with inter-second molar distance showing the greatest difference and palatal depth showing the least difference. Measurements of palatal depth and relationships of the canines to one another and to other teeth thus had the widest ranges, implying that these dimensions are the strongest determinants of maxillary arch size.

  1. Informational Equilibrium.

    DTIC Science & Technology

    1982-09-01

    that for variouis standard types of equilibria* they hold. In particular, if one uses the teaporary equilibrium framework one can use the standard ...T, the integral converges toward f’ia(da) f fU(b~dc)6(a,b,c)T( asdm ) A B C which is fR (da) f d(lib,c) U0 T (cab) A BxC Me converse Is obvious

  2. Fetal sonographic diagnosis of aortic arch anomalies.

    PubMed

    Yoo, S-J; Min, J-Y; Lee, Y-H; Roman, K; Jaeggi, E; Smallhorn, J

    2003-11-01

    Aortic arch anomalies refer to congenital abnormalities of the position or branching pattern, or both of the aortic arch. Although aortic arch anomalies are not uncommon, reports on their prenatal diagnosis are scarce. Insight into the hypothetical arch model is crucial to understanding anomalies of the aortic arch in the fetus. Recognition of the trachea, three major vessels, ductus arteriosus and descending aorta in the axial views of the upper mediastinum is necessary for a complete fetal cardiac assessment. Clues to aortic arch anomalies include abnormal position of the descending aorta, absence of the normal 'V'-shaped confluence of the ductal and aortic arches, a gap between the ascending aorta and main pulmonary artery in the three-vessel view, and an abnormal vessel behind the trachea with or without a vascular loop or ring around the trachea. Meticulous attention to anatomic landmarks will lead to successful prenatal diagnosis of important vascular rings making early postnatal management possible. Copyright 2003 ISUOG. Published by John Wiley & Sons, Ltd.

  3. Brief research on arch hinge of the steel truss arch bridge by contact problem under local stress

    NASA Astrophysics Data System (ADS)

    He, Wei; Zhu, Yinqiao; Chen, Renlong

    2017-06-01

    Because of its wide deck, elegant design and reasonable stress, the steel truss arch bridge is suitable for urban bridges. In the steel truss arch bridge, the main arch hinge is an important structure, the local structure and the stress is complex, and it is necessary to analyze the local stress state of the arch hinge. Arch hinge problem belongs to the contact problem, this paper based on Chengdu Tianfu District Shenyang Lu Xi Duan Jin Jiang in bearing steel truss arch bridge design, take the finite element software ANSYS on the main arch hinge is locally analyzed, the arch at the junction of reliable performance test. Studies have shown that half through steel truss arch bridge should be adopted by reasonable cylindrical arch hinge, and Hertz theory is in the analysis of the arch hinge contact does not apply.

  4. Safety evaluation of arch dam stability

    SciTech Connect

    Liu Defu

    1995-12-31

    The abutment sliding is the main form of failure in arch dams. Two approaches are used in defining and evaluating the stability safety factor which are the load safety factor Kp and strength safety factor Kf. So far, the Kp method is still the main method in stability model test of arch dams. This paper, to begin with the analysis of the stability formulas and the influence factors of stability in arch dams, will discuss in detail the merits and demerits of Kp and Kf methods and compare Kp with Kf for same structure. A new approach is proposed and the test steps existing problems and their solutions are all discussed.

  5. Arching in tapped deposits of hard disks.

    PubMed

    Pugnaloni, Luis A; Valluzzi, Marcos G; Valluzzi, Lucas G

    2006-05-01

    We simulate the tapping of a bed of hard disks in a rectangular box by using a pseudodynamic algorithm. In these simulations, arches are unambiguously defined and we can analyze their properties as a function of the tapping amplitude. We find that an order-disorder transition occurs within a narrow range of tapping amplitudes as has been seen by others. Arches are always present in the system although they exhibit regular shapes in the ordered regime. Interestingly, an increase in the number of arches does not always correspond to a reduction in the packing fraction. This is in contrast with what is found in three-dimensional systems.

  6. Equilibrium Shaping

    NASA Astrophysics Data System (ADS)

    Izzo, Dario; Petazzi, Lorenzo

    2006-08-01

    We present a satellite path planning technique able to make identical spacecraft aquire a given configuration. The technique exploits a behaviour-based approach to achieve an autonomous and distributed control over the relative geometry making use of limited sensorial information. A desired velocity is defined for each satellite as a sum of different contributions coming from generic high level behaviours: forcing the final desired configuration the behaviours are further defined by an inverse dynamic calculation dubbed Equilibrium Shaping. We show how considering only three different kind of behaviours it is possible to acquire a number of interesting formations and we set down the theoretical framework to find the entire set. We find that allowing a limited amount of communication the technique may be used also to form complex lattice structures. Several control feedbacks able to track the desired velocities are introduced and discussed. Our results suggest that sliding mode control is particularly appropriate in connection with the developed technique.

  7. Glowing Solar Material Arches Up and Out

    NASA Image and Video Library

    An elongated, streaming arch of solar material rose up at the sun’s edge before breaking apart in this animation of imagery captured by NASA’s Solar Dynamics Observatory on April 28, 2016. While so...

  8. L'Arche: Its Philosophy and Ideology.

    ERIC Educational Resources Information Center

    Sumarah, John

    1986-01-01

    The L'Arche movement in mental retardation based upon the work of J. Vanier stresses the value of the disabled person, the importance of mutual relationships, the importance of a sense of community, and the spiritual dimension. (CL)

  9. Magnetically driven flows in arched plasma structures.

    PubMed

    Stenson, E V; Bellan, P M

    2012-08-17

    Laboratory experiments demonstrate high-speed plasma flows from both footpoints of arched magnetic flux tubes, resulting in bulk plasma transport into the flux tube and persistent axial collimation even as the flux tube lengthens and kinks. The measured flows are in agreement with the predictions of hoop force and collimation models involving fundamental MHD forces. These forces are expected to drive plasma acceleration in other open flux configurations with arched geometries, such as those found on the solar surface.

  10. Integrated exploration locates Cincinnati arch dolomite breccias

    SciTech Connect

    Tedesco, S.A. )

    1994-11-28

    Dolomite breccias or chimneys are prolific reservoirs found along the Cincinnati arch and adjacent basins from Tennessee to Ontario. An integrated approach using seismic and surface geochemistry, augmented by subsurface geology and magnetics, has led to a dramatic increase in the number of these fields being discovered in the past 10 years. Historically the reservoirs have been found by random drilling. The paper describes the geology of the arch, breccia characteristics, and case histories of discoveries using this integrated approach.

  11. Arch dam of the Khudoni hydroelectric station

    SciTech Connect

    Dzhakeli, P.A.; Kobakhidze, V.D.; Koridze, G.I.

    1987-01-01

    This paper discusses the Khudoni hydroelectric station. The selection of the type and site of the dam are described. A plan of the hydro development with the chosen concrete arch dam is shown. Engineering-geologic and seismotectonic conditions of the chosen site are examined. Two types of design were examined for the arch dam, and they are described. Structural elements of the dam are discussed as is reinforcement, stress-strain state, underground contour and outlet works.

  12. Designing light responsive bistable arches for rapid, remotely triggered actuation

    NASA Astrophysics Data System (ADS)

    Smith, Matthew L.; Shankar, M. Ravi; Backman, Ryan; Tondiglia, Vincent P.; Lee, Kyung Min; McConney, Michael E.; Wang, David H.; Tan, Loon-Seng; White, Timothy J.

    2014-03-01

    Light responsive azobenzene functionalized polymer networks enjoy several advantages as actuator candidates including the ability to be remotely triggered and the capacity for highly tunable control via light intensity, polarization, wavelength and material alignments. One signi cant challenge hindering these materials from being employed in applications is their often relatively slow actuation rates and low power densities, especially in the absence of photo-thermal e ects. One well known strategy employed in nature for increasing actuation rate and power output is the storage and quick release of elastic energy (e.g., the Venus ytrap). Using nature as inspiration we have conducted a series of experiments and developed an equilibrium mechanics model for investigating remotely triggered snap-through of bistable light responsive arches made from glassy azobenzene functionalized polymers. After brie y discussing experimental observations we consider in detail a geometrically exact, planar rod model of photomechanical snap-through. Theoretical energy release characteristics and unique strain eld pro les provide insight toward design strategies for improved actuator performance. The bistable light responsive arches presented here are potentially a powerful option for remotely triggered, rapid motion from apparently passive structures in applications such as binary optical switches and positioners, surfaces with morphing topologies, and impulse locomotion in micro or millimeter scale robotics.

  13. 7. View showing reinforced concrete arch, east approach. The 591 ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. View showing reinforced concrete arch, east approach. The 591 foot three-hinge steel arch that spans the Cuyahoga River is flanked by twelve such approach arches. Each concrete arch consists of four arch ribs, which support the beam and slab streetcar deck on spandrel columns. As the photograph illustrates, the spandrel columns continue above the lower deck to support the roadway. - Detroit Superior High Level Bridge, Cleveland, Cuyahoga County, OH

  14. Mandibular arch perimeter changes with lip bumper treatment.

    PubMed

    Osborn, W S; Nanda, R S; Currier, G F

    1991-06-01

    The effects of lip bumper treatment on the mandibular arch were observed in 32 patients with late transitional and early permanent dentitions. Dental cast measurements were made for arch perimeter, arch length, and arch width. Cephalometric radiographs were used to determine labial tipping of the incisors and distal movement of the molars. Arch circumference increased in all patients, ranging from 0.7 mm to 8.8 mm, with an average of 4.1 mm. The mean increase in arch length was 1.2 mm and was largely attributed to anterior tipping of the mandibular incisors. Change in arch length was the most predictive variable for the increase in arch circumference. Passive changes in arch width were recorded, with a mean increase of 2.0 mm in the intercanine distance and 2.5 mm in the first premolar distance. Arch width increments contributed to the increase in arch circumference, but the increases in arch width were not found to be predictive of the change in arch circumference. Changes in either arch circumference or arch length were not related to the duration of treatment, age and sex of the patient, or the eruption status of the permanent second molars.

  15. Arch-first technique via clamshell incision: successful surgical reoperation for aortic arch dissection.

    PubMed

    Ozkara, Ahmet; Cetin, Gurkan; Mert, Murat; Akinci, Okan; Erdem, Can Caglar; Suzer, Kaya

    2005-01-01

    We report a case of successful reoperation for aortic arch dissection with use of the "arch-first" technique in a patient who had Marfan syndrome. Extracorporeal circulation was initiated via right subclavian artery cannulation, and the chest was entered through a clamshell incision for the best exposure. When the patient was cooled to 18 degrees C, the perfusion was stopped. After the 1st aortic arch anastomosis to a 30-mm Dacron graft, cerebral perfusion was reestablished via the right subclavian artery. The aortic repair was then completed. The cerebral ischemic time was 18 minutes, the aortic cross-clamp time was 69 minutes, and the total extracorporeal circulation time was 334 minutes. The patient was discharged from the hospital on postoperative day 10 with no neurologic impairment. The arch-first technique shortens the duration of brain ischemia. When combined with a clamshell incision, the technique is particularly helpful for reoperation of the aortic arch and thoracic aorta.

  16. Vibration of axially loaded circular arches

    SciTech Connect

    Sabir, A.B.; Djoudi, M.S.

    1996-11-01

    The work in the present paper is devoted to the determination of the buckling loads and natural frequencies of axially loaded arch structures. The finite element method is employed using a strain based arch element. The element is based on the conventional Euler curved beam type of strain displacement relationship and satisfies the exact representation of rigid body modes. The sub-space iteration technique is used to determine the eigenvalues and corresponding eigenvectors of the governing transcendental equation. The buckling of a pinned arch subjected to a uniform lateral pressure is first considered. The work is then extended to produce a comprehensive set of results for the vibration of axially loaded arches which are either pinned or fixed at both ends. The first symmetric and anti symmetric modes of vibration are determined and the effect of the axial load on these frequencies is investigated. The practical problem of an arch with a backfill is then considered and the effect of the elastic packing due to this backfill on the natural frequencies is determined.

  17. South Arch volcanic field9d\

    USGS Publications Warehouse

    Lipman, P.W.; Clague, D.A.; Moore, J.G.; Holcomb, R.T.

    1989-01-01

    Several young lava fields were imaged by GLORIA sidescan sonar along the Hawaiian Arch south of Hawaii. The largest, 35 by 50 km across, includes a central area characterized by high sonar backscatter and composed of several flow lobes radiating from a vent area. Reflection profiling and sea-floor photography indicate that the central lobes are flat sheet flows bounded by pillowed margins; thin surface sediment and thin palagonite rinds on lava surfaces suggest ages of 1-10 ka. Vents are localized along the arch crest near bases of Cretaceous seamounts. Two dredged flows are basanite and alkalic basalt, broadly similar to rejuvenated-stage and some pre-shield alkalic lavas on the Hawaiian Ridge. Arch volcanism represents peripheral leakage of melt from the Hawaiian hot spot over much larger areas than previously recognized. -Authors

  18. Improved dynamical modelling of the Arches cluster

    NASA Astrophysics Data System (ADS)

    Lee, Joowon; Kim, Sungsoo S.

    2014-05-01

    Recently, Clarkson et al. (2012) measured the intrinsic velocity dispersion of the Arches cluster, a young and massive star cluster in the Galactic center. Using the observed velocity dispersion profile and the surface brightness profile of Espinoza et al. (2009), they estimate the cluster's present-day mass to be ˜ 1.5×104 M⊙ by fitting an isothermal King model. In this study, we trace the best-fit initial mass for the Arches cluster using the same observed data set and also the anisotropic Fokker-Planck calculations for the dynamical evolution.

  19. A bovine aortic arch in humans.

    PubMed

    Arnáiz-García, María Elena; González-Santos, Jose María; López-Rodriguez, Javier; Dalmau-Sorli, María José; Bueno-Codoñer, María; Arévalo-Abascal, Adolfo; Fdez García-Hierro, Jose Ma; Arnáiz-García, Ana María; Arnáiz, Javier

    2014-01-01

    We describe a curious congenital variation of human aortic arch (AA) branching pattern termed the "bovine aortic arch". Rather than arising directly from the AA as a separate branch as occurs in the most common AA branching pattern, the left common carotid artery moves to the right and merges from the brachiocephalic trunk. It is the normal AA branching pattern presented in a number of animals (canines, felines or Macaque monkeys) but it has nothing to do with anatomy of AA in ruminant animals, including cattle and buffalo. That is why it is one of the most widely misnomers used in medical literature whose origin is nowadays unknown.

  20. Estabilidad de los modelos de Heggie y Ramamani

    NASA Astrophysics Data System (ADS)

    Muzzio, J. C.; Vergne, M. M.; Wachlin, F. C.; Carpintero, D. D.

    Los modelos de Heggie y Ramamani de satélites galácticos en órbitas circulares se basan en una teoría aproximada, por lo que es importante verificar su estabilidad mediante simulaciones numéricas. En esta forma, hemos logrado mostrar que son estables sobre intervalos de tiempo mucho mayores que los que lograron los propios autores de los modelos. Por otra parte, dado que hemos mostrado que el caos es significativo en estos modelos, son un sistema ideal para investigar si, pese a ello, se mantienen estacionarios. Nuestras simulaciones numéricas muestran que, pese al caos, la estacionariedad se mantiene sobre intervalos de centenares de tiempos de cruce del sistema, mucho mayores que los tiempos de Liapunov característicos de sus movimientos caóticos.

  1. 8. GENERAL ELEVATION OF BRIDGE AFTER CONCRETE FOR ARCHES HAS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. GENERAL ELEVATION OF BRIDGE AFTER CONCRETE FOR ARCHES HAS BEEN POURED BUT BEFORE FALSEWORK HAS BEEN REMOVED. TAKEN JAN 7, 1928. - Marsh Rainbow Arch Bridge, West Eighth Street North, Newton, Jasper County, IA

  2. 30. DETAIL OF HOISTWAY AT THE TOP OF THE ARCH, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    30. DETAIL OF HOISTWAY AT THE TOP OF THE ARCH, TRAIN IS IN BACKROUND, NOTE TRAIN IS ON TOP OF TRACKS - Jefferson National Expansion Memorial Arch, Mississippi River between Washington & Poplar Streets, Saint Louis, Independent City, MO

  3. VIEW FROM DOWN STREAM OF ARCH IN ELEVATION. NOTE FINISHED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW FROM DOWN STREAM OF ARCH IN ELEVATION. NOTE FINISHED INTERIOR ARCH. SSW BY 205 DEGREES - Chasm Brook Bridge, Spanning Chasm Brook on West Sargent Mountain Carriage Road, Bar Harbor, Hancock County, ME

  4. Detail, north span, from east, showing concrete "rainbow" arch rigidly ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail, north span, from east, showing concrete "rainbow" arch rigidly fixed at center pier and north abutment, and hangers linking arch rib and bridge deck - Horner Street Bridge, Horner Street over Stonycreek River, Johnstown, Cambria County, PA

  5. View of Highway 140 west of Arch Rock. Note stone ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of Highway 140 west of Arch Rock. Note stone wall at right and formed concrete wall at center. Looking north-northwest - All Year Highway, Between Arch Rock & Yosemite Valley, El Portal, Mariposa County, CA

  6. 4. NORTH ELEVATION, SHOWING BROKEN PEDIMENTED GABLE, ARCHED WINDOW IN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. NORTH ELEVATION, SHOWING BROKEN PEDIMENTED GABLE, ARCHED WINDOW IN GABLE, AND SEGMENTALLY ARCHED WINDOW HEADS ON SECOND FLOOR WINDOWS - Jacob R. Fisher House, High Street, Oldwick, Hunterdon County, NJ

  7. Arches and contact forces in a granular pile.

    PubMed

    Carlevaro, C M; Pugnaloni, L A

    2012-06-01

    Assemblies of granular particles mechanically stable under their own weight contain arches. These are structural units identified as sets of mutually stable grains. It is generally assumed that these arches shield the weight above them and should bear most of the stress in the system. We test such hypothesis by studying the stress born by in-arch and out-of-arch grains. We show that, indeed, particles in arches withstand larger stresses. In particular, the isotropic stress tends to be larger for in-arch grains whereas the anisotropic component is marginally distinguishable between the two types of particles. The contact force distributions demonstrate that an exponential tail (compatible with the maximization of entropy under no extra constraints) is followed only by the out-of-arch contacts. In-arch contacts seem to be compatible with a Gaussian distribution consistent with a recently introduced approach that takes into account constraints imposed by the local force balance on grains.

  8. 3. View locking east of 591 foot steel arch of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. View locking east of 591 foot steel arch of bridge. Arch consists of Pratt trusses divided into twenty-four, 24 foot, 7 inch panels. It was fabricated by the King Iron Bridge Company of Cleveland whose circular plaque can be seen where the arch meets the roadway. The steel arch was erected by the Berro construction Co. of Chicago. - Detroit Superior High Level Bridge, Cleveland, Cuyahoga County, OH

  9. "Open" approach to aortic arch aneurysm repair.

    PubMed

    Al Kindi, Adil H; Al Kimyani, Nasser; Alameddine, Tarek; Al Abri, Qasim; Balan, Baskaran; Al Sabti, Hilal

    2014-07-01

    Aortic arch aneurysm is a relatively rare entity in cardiac surgery. Repair of such aneurysms, either in isolation or combined with other cardiac procedures, remains a challenging task. The need to produce a relatively bloodless surgical field with circulatory arrest, while at the same time protecting the brain, is the hallmark of this challenge. However, a clear understanding of the topic allows a better and less morbid approach to such a complex surgery. Literature has shown the advantage of selective cerebral perfusion techniques in comparison with only circulatory arrest. Ability to perfuse the brain has allowed circulatory arrest temperatures at moderate hypothermia without the need for deep hypothermia. Even though cannulation site selection appears to be a minor issue, literature has shown that the subclavian/axillary route has the best outcomes and that femoral cannulation should only be reserved for no access patients. Although different techniques for arch anastomosis have been described, we routinely perform the distal first technique as we find it to be less cumbersome and easiest to reproduce. In this review our aim is to outline a systematic approach to aortic arch surgery. Starting with indications for intervention and proceeding with approaches on site of cannulation, approaches to brain protection with hypothermia and selective cerebral perfusion and finally surgical steps in performing the distal and arch vessels anastomosis.

  10. Late lower arch crowding: the aetiology reviewed.

    PubMed

    Richardson, Margaret E

    2002-06-01

    This article reviews the causes of the crowding that commonly occurs, particularly in the lower arch, after eruption of the second permanent molars. Factors discussed include mesially directed forces, in treated and untreated subjects, distally directed forces, occlusal changes, direction of eruption, tooth morphology, periodontal forces, and degenerative connective tissue changes.

  11. 11. DETAIL VIEW OF BUTTRESS 8 AND HALF OF ARCH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. DETAIL VIEW OF BUTTRESS 8 AND HALF OF ARCH 7 SHOWING THE UPSTREAM INCLINATION OF THE ARCH. ALSO VISIBLE IS A FORMER WASTE-GATE IN THE ARCH THAT IS NOW FILLED WITH CONCRETE. - Hume Lake Dam, Sequioa National Forest, Hume, Fresno County, CA

  12. 29. DETAIL OF 1 OF 3 INTERIOR CORNERS OF ARCH, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    29. DETAIL OF 1 OF 3 INTERIOR CORNERS OF ARCH, SHOWING SYSTEM OF STIFFENING BRACES OR BEAMS, APPROXIMATELY HALF WAY UP THE LEG OF THE ARCH - Jefferson National Expansion Memorial Arch, Mississippi River between Washington & Poplar Streets, Saint Louis, Independent City, MO

  13. Individualized catenary curves: their relationship to arch form and perimeter.

    PubMed

    Battagel, J M

    1996-02-01

    Study casts of the lower arches of 35 children in whom arch alignment was considered acceptable, were examined using a reflex microscope. Arch perimeter was calculated mathematically from a method which required measurement of the mesio-distal widths of the teeth only. This was described as the 'overlap' method. Arch perimeter was also calculated using individualized catenary curves for each subject. Two calculations were made, recording arch width either at the distal contact points of the first permanent molars or between their mesio-buccal cusps. Arch perimeter measured from the length of the catenary curves was consistently shorter than that calculated by the overlap method. The variation ranged from 0.02 to 4.58 mm. The catenary constructed using the distal molar contacts gave a better representation of the actual arch form: the mean discrepancy was 2.36 mm, compared with 2.86 mm with the second method where arch width was measured between mesio-buccal cusps. Both techniques for calculation of arch perimeter were highly reproducible. The catenary curve only approximated arch form well when the arch was relatively narrow across the inter canine region. For square arches this method was unsatisfactory. It is suggested that alternative techniques would be more reliable and the overlap method described here is considered satisfactory.

  14. Clinical Evaluation of Efficacy of CIA and CNA Intrusion Arches.

    PubMed

    Sharma, Swati; Vora, Sambhav; Pandey, Vinisha

    2015-09-01

    Excessive overbite is one of the most common problems that confront the orthodontist. Deep bite can be due to infraocclusion of posterior teeth, supraocclusion of anterior teeth or a combination of the two. Correction of same can be carried out by extrusion of molars, intrusion of incisors or by a combination of both respectively. Various intrusion arches are recommended for correcting deep bite by true intrusion of anterior teeth, Utility arches, Segmental arch, Connecticut Intrusion Arch (CIA) and Connecticut New Arch (CNA). The purpose of this study was to evaluate clinical efficacy of CIA and CNA intrusion arches. Tracings recorded from pre and post-treatment lateral cephalograms of 25 patients treated by CIA (Group I) and another 25 patients treated by CNA (Group II) intrusion arches in deep bite cases after four months of treatment were analysed and findings were recorded. Paired t-test was used to compare pre and post-treatment changes within Groups I and II and unpaired t-test was used to compare treatment changes between Group I and Group II. A P-value of < 0.05 was set for statistical significance. Findings of this study demonstrate that an average of 1mm of intrusion takes place with CIA intrusion arch and 1.3mm with CNA intrusion arch in a period of 4 months. Both intrusion arches do not affect the position of molar in vertical or anteroposterior plane. Both CIA and CNA intrusion arches are effective in bringing about intrusion of lower incisors.

  15. Heritability estimates of dental arch parameters in Lithuanian twins.

    PubMed

    Švalkauskienė, Vilma; Šmigelskas, Kastytis; Šalomskienė, Loreta; Andriuškevičiūtė, Irena; Šalomskienė, Aurelija; Vasiliauskas, Arūnas; Šidlauskas, Antanas

    2015-01-01

    The genetic influence on dental arch morphology may be country-specific, thus it is reasonable to check the estimates of genetics across different populations. The purpose of this study was to evaluate the heredity of dental arch morphology in the sample of Lithuanian twins with accurate zygosity determination. The study sample consisted of digital dental models of 40 monozygotic (MZ) and 32 dizygotic (DZ) twin pairs. The estimates of heritability (h(2)) for dental arch breadth and length were calculated. All dental arch breadths and lengths were statistically significantly larger in men than in women. Arch length differences between genders were less expressed than largest breadth differences. In the upper jaw the largest genetic effect was found on the arch breadth between lateral incisors. The heritability of dental arch length demonstrated similar differences between upper and lower jaw with mandible dental arch length being more genetically determined. The largest genetic impact was found on the upper dental arch breadth between lateral incisors. Similar, but lower heritability is inherent for canines and first premolars of the upper jaw and first premolars of the lower jaw. It also can be noted, that arch breadths between posterior teeth show lower heritability estimates than between anterior teeth on both jaws. The dental arch in the upper jaw has more expressed genetic component than in the lower jaw.

  16. Evaluation of the fit of preformed nickel titanium arch wires on normal occlusion dental arches

    PubMed Central

    Al-Barakati, Rakhn G.; Alqahtani, Nasser D.; AlMadi, Abdulaziz; Albarakati, Sahar F.; ALKofide, Eman A.

    2015-01-01

    Aim To determine the fits of preformed nickel titanium (NiTi) archwires on dental arches with normal occlusion. Methods Forty sets of upper and lower plaster models were obtained from men and women with Class I occlusions. Preformed 0.016″ × 0.022″ NiTi archwires from Rocky Mountain Orthodontics (RMO), 3 M Unitek, Ormco, and Dentaurum were evaluated in terms of their fits on dental arches from male, female, and combined cases. Data were analyzed by using fourth- and sixth-order polynomial equations, analysis of variance (ANOVA), and the Duncan post hoc test. Results In the upper arches, the best fit and least error were obtained with RMO Ovoid and Ormco Orthos Large archwires for male cases, but with 3 M Orthoform LA archwires for female and combined cases. In the lower arches, the best fit and least error were obtained with Ormco Orthos Large for male cases, with 3 M Orthoform LA and RMO Normal for female cases, and with 3 M Orthoform LA, RMO Normal, Ormco Orthos Large, and Ormco Orthos Small for combined cases. When both dental arches were matched, Ormco Orthos Large was the best wire for male cases. 3 M Orthoform LA was the best wire for female and combined cases. Conclusions Using an archwire form with the best fit to the dental arch should produce minimal changes in the dental arch form when NiTi wires are used and require less customization when stainless-steel wires are used. PMID:26792965

  17. Evaluation of continuous arch and segmented arch leveling techniques in adult patients--a clinical study.

    PubMed

    Weiland, F J; Bantleon, H P; Droschl, H

    1996-12-01

    The purpose of this study was to compare the efficacy of overbite correction achieved by a conventional continuous arch wire technique and the segmented arch technique as recommended by Burstone. The sample comprised 50 adult patients (age 18 to 40 years) with deep bites. Twenty-five patients were treated with a continuous arch wire technique (CAW); in the second half of the sample, the segmented arch technique (Burstone) was used for correction of the vertical malocclusion. Lateral cephalograms and plaster cast models taken before and immediately after treatment were evaluated. Statistical analysis was performed on the collected data. The results showed that both techniques produced a highly significant overbite reduction (CAW: -3.17 mm, p < 0.001; Burstone: -3.56 mm, p < 0.001). The CAW group showed an extrusion in the molar area with subsequent posterior rotation of the mandible (6occl-ML: +1.30 mm; 6occl-NSL: +1.63 mm; ML/NSL: +1.94 degrees, all p < 0.001). The Burstone group, however, showed overbite reduction by incisor intrusion without any substantial extrusion of posterior teeth (upper 1-NSL: -1.50 mm; lower 1-ML: -1.72 mm; both p < 0.001). As a consequence, no significant posterior rotation of the mandible took place (ML/NSL: +0.52 degrees, n.s.). It is concluded that in adult patients the segmented arch technique (Burstone) can be considered as being superior to a conventional continuous arch wire technique if arch leveling by incisor intrusion is indicated.

  18. Total endograft replacement of aortic arch

    PubMed Central

    Neequaye, Simon

    2013-01-01

    Total endovascular replacement of the aortic arch is a complex procedure that is often favoured when the pathology anatomy precludes a standard median sternotomy. Here we present the case of endograft repair in a 79 year old male with 6.5 cm arch aneurysm and 5.4 cm descending thoracoabdominal aneurysm. Following bilateral carotid-subclavian bypasses, a long 7 Fr sheath was advanced into the descending aorta through the common iliac artery purse string. A double curved long Lunderquist wire was guided to deep within the left ventricle, and the endograft carefully advanced over the wire. The graft was radiologically orientated, and deployed under asystolic conditions. Retrograde cannulation of the branches were accomplished, with carotid sheath placed into the branches followed by bridging stents. The graft delivery system was then removed. This approach obviates the need for a sternotomy, cumbersome extra-anatomic debranching, and hypothermic circulatory arrest. PMID:23977607

  19. Jurassic stratigraphy of the Wiggins Arch, Mississippi

    SciTech Connect

    Rhodes, J.A.; Maxwell, G.B. )

    1993-09-01

    Mobil and Shell jointly explored the Wiggins arch area in southern Mississippi from 1985 to 1991. The effort concentrated on the Jurassic Norphlet and Smackover formations. Two wells were drilled into Paleozoic crystalline rocks and one well into the Pine Hill formation. Two of these wells were located on the southern side of the Wiggins arch and provide significant data for interpreting Jurassic stratigraphy. The Mobil No. 1 U.S.A. well encountered a complete Jurassic section, but with some significantly different facies than those encountered by wells to the north. A granite wash section is the equivalent to the Frisco City formation previously only found 100 mi to the north-northeast. All 300 ft of Smackover is crystalline dolomite. The Norphlet section is entirely granite wash. The Pine Hill anhydrite is unusually thick and interpreted to be equivalent to the Louann Salt. Correlations to other wells on the Wiggins arch, particularly the Conoco No. 1 Higgins, indicate that the Jurassic can be divided into three transgressive events separated by the Norphlet/Pine Hill and Frisco City/Buckner regressive events.

  20. Aortic arch dissection: a controversy of classification.

    PubMed

    Lempel, Jason K; Frazier, Aletta Ann; Jeudy, Jean; Kligerman, Seth J; Schultz, Randall; Ninalowo, Hammed A; Gozansky, Elliott K; Griffith, Bartley; White, Charles S

    2014-06-01

    Aortic dissections originating in the ascending aorta and descending aorta have been classified as type A and type B dissections, respectively. However, dissections with intimal flap extension into the aortic arch between the innominate and left subclavian arteries are not accounted for adequately in the widely used Stanford classification. This gap has been the subject of controversy in the medical and surgical literature, and there is a tendency among many radiologists to categorize such arch dissections as type A lesions, thus making them an indication for surgery. However, the radiologic perspective is not supported by either standard dissection classification or current clinical management. In this special report, the origin of dissection classification and its evolution into current radiologic interpretation and surgical practice are reviewed. The cause for the widespread misconception about classification and treatment algorithms is identified. Institutional review board approval and waiver of informed consent were obtained as part of this HIPAA-compliant retrospective study to assess all aortic dissection studies performed at the University of Maryland Medical Center, Baltimore between 2010 and 2012 to determine the prevalence of arch dissections. Finally, a unified classification system that reconciles imaging interpretation and management implementation is proposed.

  1. Oblique slip in Laramide foreland arches

    SciTech Connect

    Erslev, E.A.; Selvig, B.; Molzer, P. . Dept. of Earth Resources)

    1993-03-01

    Don Wise was one of the first structural geologists to recognize the complex, four-dimensional (space and time) nature of basement-involved faulting in the Rocky Mountain foreland. His focus on both small scale kinematic indicators and regional tectonic hypotheses has provided a launching point for many Rocky Mountain geologists. The implications of the anastomosing patterns of Laramide foreland arches on models of regional stress and strain have provoked considerable debate. Hypotheses range from those invoking multiple stages of lateral compression from different directions to single-stage models necessitating a component of strike-slip motion in east-west and north-south arches. These hypotheses were tested using slickenline analysis of minor faulting in structures with different orientations. In Wyoming, structures paralleling the dominant northwest structural trend have slickenlines in the NE-SW vertical plane, consistent with shortening and compression in this direction. The east-west Owl Creek and Casper Mountain structures also have NE-SW trending slickenlines, indicating slip oblique to these arches. In Colorado, minor faults in the north-south margin of the northeastern Front Range also indicate oblique slip, with shortening in the NE-SW quadrant. The actual trend of the slickenlines is more easterly, however, suggesting a change of slip trajectory with latitude, not time, possibly in response to identation by the Colorado Plateau.

  2. Observation of plasma microwave emission during the injection of supersonic plasma flows into magnetic arch

    NASA Astrophysics Data System (ADS)

    Viktorov, M. E.; Mansfeld, D. A.; Vodopyanov, A. V.; Kiryuhin, N. D.; Golubev, S. V.; Yushkov, G. Yu.

    2017-05-01

    The process of plasma deceleration during the injection of supersonic plasma flow across the magnetic field of an arched configuration is experimentally demonstrated. Pulsed plasma microwave emission in the electron cyclotron frequency range is observed. It is shown that the frequency spectrum of plasma emission is determined by the position of the deceleration region in the magnetic field of the magnetic arc, and its bandwidth is defined by the magnetic field inhomogeneity in the deceleration region. The observed emission can be related to the cyclotron mechanism of wave generation by non-equilibrium energetic electrons in the dense plasma.

  3. The Foot's Arch and the Energetics of Human Locomotion.

    PubMed

    Stearne, Sarah M; McDonald, Kirsty A; Alderson, Jacqueline A; North, Ian; Oxnard, Charles E; Rubenson, Jonas

    2016-01-19

    The energy-sparing spring theory of the foot's arch has become central to interpretations of the foot's mechanical function and evolution. Using a novel insole technique that restricted compression of the foot's longitudinal arch, this study provides the first direct evidence that arch compression/recoil during locomotion contributes to lowering energy cost. Restricting arch compression near maximally (~80%) during moderate-speed (2.7 ms(-1)) level running increased metabolic cost by + 6.0% (p < 0.001, d = 0.67; unaffected by foot strike technique). A simple model shows that the metabolic energy saved by the arch is largely explained by the passive-elastic work it supplies that would otherwise be done by active muscle. Both experimental and model data confirm that it is the end-range of arch compression that dictates the energy-saving role of the arch. Restricting arch compression had no effect on the cost of walking or incline running (3°), commensurate with the smaller role of passive-elastic mechanics in these gaits. These findings substantiate the elastic energy-saving role of the longitudinal arch during running, and suggest that arch supports used in some footwear and orthotics may increase the cost of running.

  4. D-TGA Combined With Left Arch Atresia of a Double Aortic Arch.

    PubMed

    Zhou, Dan; Song, Laichun; Tao, Liang; Zhou, Hong

    2017-05-05

    A three-month-old female underwent an arterial switch operation for transposition of the great arteries (TGA) with concomitant ventricular septal defect (VSD). After the operation, the patient suffered from stubborn pulmonary infection with increased airway resistance, and could not be weaned from a ventilator. Multispiral computed tomography (CT) scanning suggested a double aortic arch with left arch atresia. The patient underwent a second procedure to resection the left aortic arch. The patient gradually recovered and was successfully weaned from the ventilator. Copyright © 2017 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

  5. Accuracy of impressions obtained with dual-arch trays.

    PubMed

    Wöstmann, Bernd; Rehmann, Peter; Balkenhol, Markus

    2009-01-01

    This study aimed to analyze the accuracy resulting from dual-arch impressions when compared to conventional impressions in complex preparations (ie, inlay and partial crown). One hundred eighty impressions were made using two different dual-arch trays; conventional trays served as the control. The accuracy of the dies obtained (Fuji-Rock EP, GC Europe) was assessed indirectly from the change of 59 transversal dimensions. Statistical analysis (t test, analysis of variance) revealed that less rigid dual-arch trays performed better than rigid ones. Though the inlay preparation was more difficult to reproduce with dual-arch trays, it can be concluded that the accuracy obtainable with nonrigid dual-arch trays is comparable to impressions taken from full-arch trays.

  6. Comparison of overjet among 3 arch types in normal occlusion.

    PubMed

    Kim, Byung-In; Bayome, Mohamed; Kim, Yoonji; Baek, Seung-Hak; Han, Seong Ho; Kim, Seong-Hun; Kook, Yoon-Ah

    2011-03-01

    The purposes of this study were to examine the amounts of overjet in the anterior and posterior segments of 3 arch forms by using facial axis points on 3-dimensional virtual models and to verify the minimum posterior extension required for classification of the arch form in normal occlusions. Facial axis points were digitized on 97 virtual models with normal occlusion, classified into 20 tapered, 25 ovoid, and 52 square arch forms. Intercanine and intermolar arch widths and depths were measured. The best-fitting curves were created, and overjet was measured at each facial axis point. Two-way analysis of variance (ANOVA) was performed to assess the relationship between arch form and overjet in different areas. The minimum posterior extension to determine arch type was analyzed with the chi-square test. Subjects with a tapered arch form had larger overjet compared with those with ovoid and square forms, except at the central incisor. A significant difference in overjet among different areas was found in subjects with a square arch form (P <0.0001). No significant difference (P = 0.864) was found among the first and second premolar and the first molar groups for classifying arch-form types. A significant difference was found in anterior and posterior overjet according to arch types. The extension to the first premolar was sufficient to classify arch form type. It might be beneficial to consider more coordinated preformed superelastic archwires according to variations in overjet of different arch types. Copyright © 2011 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  7. Bilateral first and second arch anomalies: a rare presentation.

    PubMed

    Singh, Amit Pal; Kumar, Virad; Narula, Vineet; Meher, Ravi; Raj, Anoop

    2012-04-01

    Branchial sinuses are one of the most common congenital anomalies present. They are usually unilateral; bilateral cases are present but are rare. The presentation of bilateral branchial sinus anomalies along with bilateral first arch anomalies is very rare. Here, we present a case of bilateral first arch anomalies co-existing with bilateral second arch anomalies in a patient with no related family history and no associated syndrome.

  8. The Optimized Arch Design Theory and Engineering Practices,

    DTIC Science & Technology

    1984-03-12

    ellipses, three centered circles, parabolas, catenary , horseshoe arches etc. (Fig. 1). 5 (6) . • -=.’ (𔄁)r ?F -42 i0 R(2) M" 4 3 9 )4 fu ix- = -, ME...10)• (14) Fig. 1 Arch shapes commonly used in engineering. Key: (1) Semi-circle, isometric ellipse; (2) Three- centered circle; (3) Catenary ; (4...circle; (12) Minor arc cyclotomic; (13) Catenary ; (14) Parabola. Then what generalities and characteristics do these arch shapes have? What are the

  9. Relationship between the mobility of medial longitudinal arch and postural control.

    PubMed

    Birinci, Tansu; Demirbas, Sule Badıllı

    2017-05-01

    The aim of this study was to analyze the relationship between the medial longitudinal arch mobility and static and dynamic balance. A total of 50 subjects (25 female, and 25 male; Mean age: 22.2 ± 1.3 years; BMI: 22.8 ± 3.8 kg/m(2)) were included in this study. The relative arch deformity (RAD) was calculated with both 10% and 90% weight bearing (WB). Static balance was evaluated with Single Leg Stance Test and dynamic balance with TechnoBody PK 200WL computerized balance device. Subjects were evaluated for goniometric measurements of lower extremity joints, leg dominance and leg-length discrepancy. Bipedal dynamic balance was correlated with both feet length at 10% WB and 90% WB. There was a correlation between the dynamic balance on dominant foot and RAD value on the aspect of Medium Speed (r = -0.32, p = 0.02), Perimeter Length (r = -0.32, p = 0.02) and Anterior-Posterior Sway (r = 0.36, p = 0.01). Static balance was unaffected by RAD value when the visual system was eliminated. Our results suggest that decrease of arch mobility on the dominant foot is associated with posterior sway by causing knee or hip strategy and preventing ankle strategy even in small perturbations. The rate of deviation from the equilibrium point and the degree of total swaying increase when arch mobility decreases. Copyright © 2016 Turkish Association of Orthopaedics and Traumatology. Production and hosting by Elsevier B.V. All rights reserved.

  10. 66. CORBELS, BLIND ARCHES & SHIELDS, COMMONS EAST WALL, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    66. CORBELS, BLIND ARCHES & SHIELDS, COMMONS EAST WALL, LOOKING EAST - Smithsonian Institution Building, 1000 Jefferson Drive, between Ninth & Twelfth Streets, Southwest, Washington, District of Columbia, DC

  11. Arched gonadal arteries in the South African negro.

    PubMed Central

    Grine, F E; Kramer, B

    1981-01-01

    The frequency with which the gonadal arteries follow a recurrent course, upwards and arching over the renal veins before descending to the gonads, is recorded for the South African Negro. The gonadal arteries follow such a course on the left side in 17, 2% and on the right side in 22% of cases. This incidence for arched left sided arteries is comparable to that recorded in other studies, but the frequency for arched right sided arteries in the South African Negro appears to be higher. Recognition of arching gonadal arteries is of importance to the vascular surgeon and urologist. PMID:7298490

  12. 2. Elkmont, deck view of corrugated arched bridge. Great ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. Elkmont, deck view of corrugated arched bridge. - Great Smoky Mountains National Park Roads & Bridges, Elkmont Vehicle Bridge, Spanning Little River at Elkmont Campground, Gatlinburg, Sevier County, TN

  13. 3. Elkmont, underside detail of corrugated arched bridge. Great ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. Elkmont, underside detail of corrugated arched bridge. - Great Smoky Mountains National Park Roads & Bridges, Elkmont Vehicle Bridge, Spanning Little River at Elkmont Campground, Gatlinburg, Sevier County, TN

  14. Mathematical model of a moment-less arch

    PubMed Central

    2016-01-01

    This paper presents a mathematical model for predicting the geometrical shapes of rigid, two-pin, moment-less arches of constant cross section. The advancement of this work lies in the inclusion of arch self-weight and the ability to produce moment-less arch forms for any span/rise ratio, and any ratio of uniformly distributed load per unit span, w, to uniformly distributed arch weight per unit arch length, q. The model is used to derive the shapes of two classical ‘moment-less’ arch forms: parabolic and catenary, prior to demonstrating a general case, not restricted by the unrealistic load assumptions (absence of q, in the case of a parabolic form, or no w, in the case of a catenary arch). Using the same value of span/rise ratio, and w/q>1, the behaviour of the moment-less and parabolic arches under permanent loading, (w+q), is analysed. Results show the former to be developing much lower stresses than its parabolic rival, even when there are relatively small differences in the two geometries; for a medium span/rise ratio of 4 and w/q=2, differences in the parabolic and moment-less arch geometries would, in practical terms, be viewed as insignificant, but the stresses in them are different. PMID:27436970

  15. ARCH TYPE MAGAZINE # 2131. INTERIOR LOOKING TOWARD ENTRY. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    ARCH TYPE MAGAZINE # 2131. INTERIOR LOOKING TOWARD ENTRY. - Naval Magazine Lualualei, Headquarters Branch, Magazine Type, Various roads in northern & eastern portions of installation, Pearl City, Honolulu County, HI

  16. Mathematical model of a moment-less arch.

    PubMed

    Lewis, W J

    2016-06-01

    This paper presents a mathematical model for predicting the geometrical shapes of rigid, two-pin, moment-less arches of constant cross section. The advancement of this work lies in the inclusion of arch self-weight and the ability to produce moment-less arch forms for any span/rise ratio, and any ratio of uniformly distributed load per unit span, w, to uniformly distributed arch weight per unit arch length, q. The model is used to derive the shapes of two classical 'moment-less' arch forms: parabolic and catenary, prior to demonstrating a general case, not restricted by the unrealistic load assumptions (absence of q, in the case of a parabolic form, or no w, in the case of a catenary arch). Using the same value of span/rise ratio, and w/q>1, the behaviour of the moment-less and parabolic arches under permanent loading, (w+q), is analysed. Results show the former to be developing much lower stresses than its parabolic rival, even when there are relatively small differences in the two geometries; for a medium span/rise ratio of 4 and w/q=2, differences in the parabolic and moment-less arch geometries would, in practical terms, be viewed as insignificant, but the stresses in them are different.

  17. The Geologic Story of Arches National Park

    USGS Publications Warehouse

    Lohman, Stanley William

    1975-01-01

    According to former Superintendent Bates Wilson (1956), Prof. Lawrence M. Gould, of the University of Michigan, was the first to recognize the geologic and scenic values of the Arches area in eastern Utah and to urge its creation as a national monument. Mrs. Faun McConkie Tanner told me that Professor Gould, who had done a thesis problem in the nearby La Sal Mountains, was first taken through the area by Marv Turnbow, third owner of Wolfe cabin. (See p. 12.) When Professor Gould went into ecstasy over the beautiful scenery, Turnbow replied, 'I didn't know there was anything unusual about it.'

  18. Bovine aortic arch with supravalvular aortic stenosis.

    PubMed

    Idhrees, Mohammed; Cherian, Vijay Thomas; Menon, Sabarinath; Mathew, Thomas; Dharan, Baiju S; Jayakumar, K

    2016-09-01

    A 5-year-old boy was diagnosed to have supravalvular aortic stenosis (SVAS). On evaluation of CT angiogram, there was associated bovine aortic arch (BAA). Association of BAA with SVAS has not been previously reported in literature, and to best of our knowledge, this is the first case report of SVAS with BAA. Recent studies show BAA as a marker for aortopathy. SVAS is also an arteriopathy. In light of this, SVAS can also possibly be a manifestation of aortopathy associated with BAA.

  19. A bovine aortic arch in humans

    PubMed Central

    Arnáiz-García, María Elena; González-Santos, Jose María; López-Rodriguez, Javier; Dalmau-Sorli, María José; Bueno-Codoñer, María; Arévalo-Abascal, Adolfo; Fdez García-Hierro, Jose Ma; Arnáiz-García, Ana María; Arnáiz, Javier

    2014-01-01

    We describe a curious congenital variation of human aortic arch (AA) branching pattern termed the “bovine aortic arch”. Rather than arising directly from the AA as a separate branch as occurs in the most common AA branching pattern, the left common carotid artery moves to the right and merges from the brachiocephalic trunk. It is the normal AA branching pattern presented in a number of animals (canines, felines or Macaque monkeys) but it has nothing to do with anatomy of AA in ruminant animals, including cattle and buffalo. That is why it is one of the most widely misnomers used in medical literature whose origin is nowadays unknown. PMID:24973853

  20. A Binomial Integer-Valued ARCH Model.

    PubMed

    Ristić, Miroslav M; Weiß, Christian H; Janjić, Ana D

    2016-11-01

    We present an integer-valued ARCH model which can be used for modeling time series of counts with under-, equi-, or overdispersion. The introduced model has a conditional binomial distribution, and it is shown to be strictly stationary and ergodic. The unknown parameters are estimated by three methods: conditional maximum likelihood, conditional least squares and maximum likelihood type penalty function estimation. The asymptotic distributions of the estimators are derived. A real application of the novel model to epidemic surveillance is briefly discussed. Finally, a generalization of the introduced model is considered by introducing an integer-valued GARCH model.

  1. [Single coronary artery and right aortic arch].

    PubMed

    Martínez-Quintana, Efrén; Rodríguez-González, Fayna

    2015-01-01

    Coronary anomalies are mostly asymptomatic and diagnosed incidentally during coronary angiography or echocardiography. However, they must be taken into account in the differential diagnosis of angina, dyspnea, syncope, acute myocardial infarction or sudden death in young patients. The case is presented of two rare anomalies, single coronary artery originating from right sinus of Valsalva and right aortic arch, in a 65 year-old patient with atherosclerotic coronary artery disease treated percutaneously. Copyright © 2014 Sociedad Española de Arteriosclerosis. Published by Elsevier España. All rights reserved.

  2. Clinical Evaluation of Efficacy of CIA and CNA Intrusion Arches

    PubMed Central

    Vora, Sambhav; Pandey, Vinisha

    2015-01-01

    Background and Objectives Excessive overbite is one of the most common problems that confront the orthodontist. Deep bite can be due to infraocclusion of posterior teeth, supraocclusion of anterior teeth or a combination of the two. Correction of same can be carried out by extrusion of molars, intrusion of incisors or by a combination of both respectively. Various intrusion arches are recommended for correcting deep bite by true intrusion of anterior teeth, Utility arches, Segmental arch, Connecticut Intrusion Arch (CIA) and Connecticut New Arch (CNA). The purpose of this study was to evaluate clinical efficacy of CIA and CNA intrusion arches. Materials and Methods Tracings recorded from pre and post-treatment lateral cephalograms of 25 patients treated by CIA (Group I) and another 25 patients treated by CNA (Group II) intrusion arches in deep bite cases after four months of treatment were analysed and findings were recorded. Statistical Analysis Paired t-test was used to compare pre and post-treatment changes within Groups I and II and unpaired t-test was used to compare treatment changes between Group I and Group II. A P-value of < 0.05 was set for statistical significance. Results Findings of this study demonstrate that an average of 1mm of intrusion takes place with CIA intrusion arch and 1.3mm with CNA intrusion arch in a period of 4 months. Both intrusion arches do not affect the position of molar in vertical or anteroposterior plane. Interpretation & Conclusion Both CIA and CNA intrusion arches are effective in bringing about intrusion of lower incisors. PMID:26501008

  3. Blood flow characteristics in the aortic arch

    NASA Astrophysics Data System (ADS)

    Prahl Wittberg, Lisa; van Wyk, Stevin; Mihaiescu, Mihai; Fuchs, Laszlo; Gutmark, Ephraim; Backeljauw, Philippe; Gutmark-Little, Iris

    2012-11-01

    The purpose with this study is to investigate the flow characteristics of blood in the aortic arch. Cardiovascular diseases are associated with specific locations in the arterial tree. Considering atherogenesis, it is claimed that the Wall Shear Stress (WSS) along with its temporal and spatial gradients play an important role in the development of the disease. The WSS is determined by the local flow characteristics, that in turn depends on the geometry as well as the rheological properties of blood. In this numerical work, the time dependent fluid flow during the entire cardiac cycle is fully resolved. The Quemada model is applied to account for the non-Newtonian properties of blood, an empirical model valid for different Red Blood Cell loading. Data obtained through Cardiac Magnetic Resonance Imaging have been used in order to reconstruct geometries of the the aortic arch. Here, three different geometries are studied out of which two display malformations that can be found in patients having the genetic disorder Turner's syndrome. The simulations show a highly complex flow with regions of secondary flow that is enhanced for the diseased aortas. The financial support from the Swedish Research Council (VR) and the Sweden-America Foundation is gratefully acknowledged.

  4. Patient management in aortic arch surgery†.

    PubMed

    Peterss, Sven; Pichlmaier, Maximilian; Curtis, Alexander; Luehr, Maximilian; Born, Frank; Hagl, Christian

    2017-01-01

    SummaryAortic arch surgery requires complex patient management beyond the manual replacement of the diseased vessel. These procedures include (i) a thorough and pathologically adjusted preoperative evaluation, (ii) initiation and control of cardiopulmonary bypass, (iii) cerebral protection strategies and (iv) techniques to protect the abdominal end organs during prolonged operations. Due to the complexity of aortic arch procedures, multimodal real-time surveillance is required during all stages of the operation. Although having the patient survive the operation is the major goal, further observation is necessary because of the chronicity of the disease. This review summarizes specific aspects of patient management during and after operations requiring periods of circulatory arrest, without necessarily referring to all studies on this topic. The pros and cons of different strategies are weighed against each other, including the personal experience of the authors. A number of questions are raised without providing a 'right' or 'wrong' answer. We show that a number of different well-established strategies can result in comparable excellent long-lasting surgical results.

  5. 1. CONTEXTUAL VIEW, LOOKING DOWNSTREAM (NORTHERLY) OF THE CONCRETE ARCH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. CONTEXTUAL VIEW, LOOKING DOWNSTREAM (NORTHERLY) OF THE CONCRETE ARCH ('ONE-WAY BRIDGE') THAT PROVIDES PRIVATE (WWP) ACCESS TO THE MIDDLE CHANNEL OF THE POST FALLS POWER PLANT. - Washington Water Power Company Post Falls Power Plant, Concrete Arch Bridge, West of intersection of Spokane & Fourth Streets, Post Falls, Kootenai County, ID

  6. 3. PORTAL VIEW OF THE CONCRETE ARCH (ONEWAY BRIDGE) THAT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. PORTAL VIEW OF THE CONCRETE ARCH (ONE-WAY BRIDGE) THAT PROVIDES ACCESS TO THE MIDDLE CHANNEL DAM AND POWER PLANT, LOOKING WEST. - Washington Water Power Company Post Falls Power Plant, Concrete Arch Bridge, West of intersection of Spokane & Fourth Streets, Post Falls, Kootenai County, ID

  7. 4. PORTAL VIEW OF THE CONCRETE ARCH (ONEWAY BRIDGE) THAT ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. PORTAL VIEW OF THE CONCRETE ARCH (ONE-WAY BRIDGE) THAT EXITS THE MIDDLE CHANNEL ISLAND AND POST FALLS POWER PLANT, LOOKING EAST. - Washington Water Power Company Post Falls Power Plant, Concrete Arch Bridge, West of intersection of Spokane & Fourth Streets, Post Falls, Kootenai County, ID

  8. Adult presentation with vascular ring due to double aortic arch.

    PubMed

    Kafka, Henryk; Uebing, Anselm; Mohiaddin, Raad

    2006-11-01

    This is a case report on the use of cardiovascular magnetic resonance imaging to diagnose vascular ring due to double aortic arch in an adult presenting with an abnormal chest X-ray. The experience in this case and the literature review identify the benefits of using cardiovascular magnetic resonance imaging to clarify complex aortic arch anatomy.

  9. Lateral testing of glued laminated timber tudor arch

    Treesearch

    Douglas R. Rammer; Philip Line

    2016-01-01

    Glued laminated timber Tudor arches have been in wide use in the United States since the 1930s, but detailed knowledge related to seismic design in modern U.S. building codes is lacking. FEMA P-695 (P-695) is a methodology to determine seismic performance factors for a seismic force resisting system. A limited P-695 study for glued laminated timber arch structures...

  10. 10. COPY OF OBLIQUE PHOTOGRAPH SHOWING ARCH HANGAR AT RIGHT, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. COPY OF OBLIQUE PHOTOGRAPH SHOWING ARCH HANGAR AT RIGHT, BUILDING 8200 (OBSERVATION TOWER) AT LEFT, AND B-52 AIRCRAFT PARKED ALONG APRON IN BACKGROUND, DATED OCTOBER 1967, PHOTOGRAPH FROM BASE MASTER PLAN LOCATED AT AIR FORCE BASE CONVERSION AGENCY, LORING AIR FORCE BASE, MAINE. - Loring Air Force Base, Arch Hangar, East of Arizona Road near southern end of runway, Limestone, Aroostook County, ME

  11. 15. Arched, concrete bridge along elevated rightofway of Shaker Rapid ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. Arched, concrete bridge along elevated right-of-way of Shaker Rapid Transit through the east side of city of Cleveland, labelled: 'View Toward West Along Northerly Side Arches at E. 90th St. and Westerly.' 1914. - Shaker Heights Rapid Transit Line, Cleveland, Cuyahoga County, OH

  12. VIEW TO THE SOUTHEAST. SPANDREL ARCHES OF THE KELLER BRIDGE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW TO THE SOUTHEAST. SPANDREL ARCHES OF THE KELLER BRIDGE ARE SEEN ON THE LEFT; THE SUPERSTRUCTURE OF THE TENNESSEE RIVER RISES ABOVE THE KELLER AND OBSCURES ITS ARCHES. - Keller Memorial Bridge, Spanning Tennessee River at U.S. Highway 31, Decatur, Morgan County, AL

  13. 12. AN IMAGE OF THE ARCH ENTRADOS LOOKING SOUTH FROM ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. AN IMAGE OF THE ARCH ENTRADOS LOOKING SOUTH FROM THE NORTH SIDE OF U.S. 40. THIS DETAIL CLEARLY SHOWS THE FOUR LONGITUDINAL ARCH CASTINGS AND THE GHOSTS OF THE BOARDS USED AS FORMS. - Vandalia Railroad Bridge, Spanning U.S. Route 40, Indianapolis, Marion County, IN

  14. 145. Camp Creek Bridge. This is a Roman spandrel arch ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    145. Camp Creek Bridge. This is a Roman spandrel arch bridge built in 1939. View shows the stone arch stones and the stone facing on the headwall and wing wall. Looking north-northwest. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  15. Ambient resonance of Mesa Arch, Canyonlands National Park, Utah

    NASA Astrophysics Data System (ADS)

    Starr, Alison M.; Moore, Jeffrey R.; Thorne, Michael S.

    2015-08-01

    We analyzed the resonance characteristics of a prominent natural arch in Canyonlands National Park, Mesa Arch, as measured from ambient seismic data. Evaluating spectral and polarization attributes, we distinguished the first four resonant frequencies of the arch, 2.9, 6.0, 6.9, and 8.5 Hz, as well as basic properties of the associated mode shapes. We then affirmed experimental data using 3-D numerical modal analysis, providing estimates of material properties and clarifying vibrational mode shapes. Monitoring resonant frequencies over time, we searched for shifts associated with changing environmental conditions and long-term progressive damage. We measured ~3% direct daily variation in resonant frequency associated with changing rock temperature, thermal stress, and stiffening of the rock matrix. Independent tilt data showed similar diurnal cycles associated with thermoelastic stresses and deformation of the arch. We observed no permanent resonant frequency shifts related to irreversible damage of Mesa Arch during our study period.

  16. Critical Transitions in Early Embryonic Aortic Arch Patterning and Hemodynamics

    PubMed Central

    Kowalski, William J.; Dur, Onur; Wang, Yajuan; Patrick, Michael J.; Tinney, Joseph P.; Keller, Bradley B.; Pekkan, Kerem

    2013-01-01

    Transformation from the bilaterally symmetric embryonic aortic arches to the mature great vessels is a complex morphogenetic process, requiring both vasculogenic and angiogenic mechanisms. Early aortic arch development occurs simultaneously with rapid changes in pulsatile blood flow, ventricular function, and downstream impedance in both invertebrate and vertebrate species. These dynamic biomechanical environmental landscapes provide critical epigenetic cues for vascular growth and remodeling. In our previous work, we examined hemodynamic loading and aortic arch growth in the chick embryo at Hamburger-Hamilton stages 18 and 24. We provided the first quantitative correlation between wall shear stress (WSS) and aortic arch diameter in the developing embryo, and observed that these two stages contained different aortic arch patterns with no inter-embryo variation. In the present study, we investigate these biomechanical events in the intermediate stage 21 to determine insights into this critical transition. We performed fluorescent dye microinjections to identify aortic arch patterns and measured diameters using both injection recordings and high-resolution optical coherence tomography. Flow and WSS were quantified with 3D computational fluid dynamics (CFD). Dye injections revealed that the transition in aortic arch pattern is not a uniform process and multiple configurations were documented at stage 21. CFD analysis showed that WSS is substantially elevated compared to both the previous (stage 18) and subsequent (stage 24) developmental time-points. These results demonstrate that acute increases in WSS are followed by a period of vascular remodeling to restore normative hemodynamic loading. Fluctuations in blood flow are one possible mechanism that impacts the timing of events such as aortic arch regression and generation, leading to the variable configurations at stage 21. Aortic arch variations noted during normal rapid vascular remodeling at stage 21 identify a

  17. Determining shapes and dimensions of dental arches for the use of straight-wire arches in lingual technique

    PubMed Central

    Kairalla, Silvana Allegrini; Scuzzo, Giuseppe; Triviño, Tarcila; Velasco, Leandro; Lombardo, Luca; Paranhos, Luiz Renato

    2014-01-01

    INTRODUCTION: This study aims to determine the shape and dimension of dental arches from a lingual perspective, and determine shape and size of a straight archwire used for lingual Orthodontics. METHODS: The study sample comprised 70 Caucasian Brazilian individuals with normal occlusion and at least four of Andrew's six keys. Maxillary and mandibular dental casts were digitized (3D) and the images were analyzed by Delcam Power SHAPET 2010 software. Landmarks on the lingual surface of teeth were selected and 14 measurements were calculated to determine the shape and size of dental arches. RESULTS: Shapiro-Wilk test determined small arch shape by means of 25th percentile (P25%) - an average percentile for the medium arch; and a large one determined by means of 75th percentile (P75%). T-test revealed differences between males and females in the size of 12 dental arches. CONCLUSION: The straight-wire arch shape used in the lingual straight wire technique is a parabolic-shaped arch, slightly flattened on its anterior portion. Due to similarity among dental arch sizes shown by males and females, a more simplified diagram chart was designed. PMID:25715725

  18. Role of fracture localization in arch formation, Arches National Park, Utah

    SciTech Connect

    Cruikshank, K.M.; Aydin, A. )

    1994-07-01

    Spectacular rock fins on the flanks of Salt Valley anticline in southeast Utah are formed by erosion along zones of joints. Within a rock fin, arches form where intense fracturing is localized. Fracture localization is controlled by shear displacement along existing horizontal or vertical discontinuities. Horizontal discontinuities may be shale layers, shale lenses, or bedding planes, whereas vertical discontinuities are usually preexisting joint segments. The roof and overall shape of an arch is controlled by existing shale layers, interfaces between sandstones of different properties, or secondary fractures due to shear on vertical joints. Joints that bound rock fins are related to the formation of the diapir-cored Salt Valley anticline. Shear displacement along existing discontinuities, which localizes intense fracturing, is probably related to the growth of Salt Valley anticline and its subsequent collapse due to dissolution of the anticlines salt core. 31 refs., 11 figs.

  19. Getting Freshman in Equilibrium.

    ERIC Educational Resources Information Center

    Journal of Chemical Education, 1983

    1983-01-01

    Various aspects of chemical equilibrium were discussed in six papers presented at the Seventh Biennial Conference on Chemical Education (Stillwater, Oklahoma 1982). These include student problems in understanding hydrolysis, helping students discover/uncover topics, equilibrium demonstrations, instructional strategies, and flaws to kinetic…

  20. Getting Freshman in Equilibrium.

    ERIC Educational Resources Information Center

    Journal of Chemical Education, 1983

    1983-01-01

    Various aspects of chemical equilibrium were discussed in six papers presented at the Seventh Biennial Conference on Chemical Education (Stillwater, Oklahoma 1982). These include student problems in understanding hydrolysis, helping students discover/uncover topics, equilibrium demonstrations, instructional strategies, and flaws to kinetic…

  1. An unusually medial axillary arch muscle.

    PubMed Central

    Dharap, A

    1994-01-01

    In the left upper limb of an adult male cadaver a triangular muscular slip, 3.5 cm long and 2.5 cm wide, arose from the lower border of latissimus dorsi just proximal to its tendon of insertion. It was inserted by a slender 6 cm long tendon mainly into the coracoid process of the scapula. Three short fibrous strands radiated from this slender tendon to gain attachments to pectoralis minor and the common tendon of origin of the short head of biceps brachii and coracobrachialis. In addition 2 flat tendinous bands attached the margin of this muscular slip to teres major. The thoracodorsal nerve entered the main bulk of latissimus dorsi close to the muscular slip but did not supply a separate branch to the latter. This is an axillary arch muscle in an unusually medial location. Images Fig. 1 Fig. 2 PMID:7928652

  2. Arching in three-dimensional clogging

    NASA Astrophysics Data System (ADS)

    Török, János; Lévay, Sára; Szabó, Balázs; Somfai, Ellák; Wegner, Sandra; Stannarius, Ralf; Börzsönyi, Tamás

    2017-06-01

    Arching in dry granular material is a long established concept, however it remains still an open question how three-dimensional orifices clog. We investigate by means of numerical simulations and experimental data how the outflow creates a blocked configuration of particles. We define the concave surface of the clogged dome by two independent methods (geometric and density based). The average shape of the cupola for spheres is almost a hemisphere but individual samples have large holes in the structure indicating a blocked state composed of two-dimensional force chains rather than three-dimensional objects. The force chain structure justifies this assumption. For long particles the clogged configurations display large variations, and in certain cases the empty region reaches a height of 5 hole diameters. These structures involve vertical walls consisting of horizontally placed stable stacking of particles.

  3. Equilibrium of KSTAR Plasma

    NASA Astrophysics Data System (ADS)

    You, K.-I.; Lee, D.-K.; Lee, S. G.; Bak, J. G.; Hahn, S. H.; Lao, L.; Kstar Team

    2011-10-01

    We have installed the EFIT code on our computing system and made some modification to reconstruct the plasma equilibrium of KSTAR (Korea Superconducting Tokamak Advanced Research). KSTAR PF and TF coil systems use a CICC (Cable-In-Conduit Conductor) type superconductor. The CICC jacket material for most PF and all TF coils is Incoloy 908, which is a magnetic material with relative magnetic permeability greater than 10 in low external field. We newly introduced Diamagnetic Loop and variational Motion Stark Effect signals to equilibrium reconstruction. In this paper, we present some results of equilibrium reconstruction with the EFIT code, assess the effects of newly introduced diagnsotics signal on the equilibrium reconstruction and compare the EFIT results with the various diagnostics data in various plasma conditions including H- and L- modes. In addition, we will show the Incoloy908 effects on the plasma equilibrium.

  4. Aplicación del Teorema de Nekhorochev para tiempos de estabilidad en Mecánica Celeste

    NASA Astrophysics Data System (ADS)

    Miloni, O.; Núñez, J.; Brunini, A.

    En Mecánica Celeste, uno de los problemas centrales consiste en la determinación de los tiempos de estabilidad. El teorema de Nekhorochev proporciona un método para dicho estudio, para un sistema determinado por un hamiltoniano descripto en las variables acción-ángulo. El trabajo consiste en la acotación tanto del potencial perturbador y de la matriz hessiana del hamiltoniano integrable para determinar luego el tiempo de estabilidad de dicho sistema, donde por estabilidad se entiende la separación en norma infinito en el espacio de las acciones.

  5. Dental arch diameters and relationships to oral habits.

    PubMed

    Aznar, T; Galán, A F; Marín, I; Domínguez, A

    2006-05-01

    The objective was to analyze variations in dental arch width in relation to oral habits. Maxillary and mandibular intercanine and intermolar distance were determined in relation to certain oral habits in 1297 children (ages 3 to 6 years). After an oral examination, the parents of each child completed a questionnaire about oral habits, including the use of a dummy or a bottle (or both), finger sucking, mouth breathing, breast- or bottle-feeding, and duration of these habits. Data were subjected to statistical analysis by the chi-square test for qualitative variables and analysis of variance for quantitative variables with homogeneous variances. Statistical significance was P < .05. In general, the maxillary arch was larger than the mandibular arch with regard to both the intercanine and the intermolar distances and more significantly so in boys. In relation to age, a significant increase was found only for the mandibular intercanine distance (P = .001). When arch width was analyzed in relation to various oral habits, the maxillary intercanine distance was less in children who used a dummy, especially one of a round design (P = .003). The maxillary intercanine distance was also less in children who breathed through their mouth (P = .002). In most cases, dummy use and mouth breathing were associated with a reduction in the intercanine distance in the maxillary arch. A dummy habit leads to a reduction in maxillary arch width, and mouth breathing causes a reduction in the size of both arches.

  6. Variation in Formation of Superficial Palmar Arches with Clinical Implications

    PubMed Central

    Vatsalaswamy, P.; Bahetee, B.H.

    2014-01-01

    Background: Knowledge of the variations in the arterial supply of hand has reached a point of practical importance with the advent of microvascular surgery for revascularization, replantation and composite tissue transfers. Arterial supply of hand is derived from two anastomotic arches, formed between two main arteries of forearm i.e. radial, ulnar and their branches, in the palm. Objective: The superficial palmar arch shows variation in formation at the radial side. In the present study we have recorded its data which would help in its clinical and surgical implications. Material and Methods: In the present study we have studied the formation of superficial palmar arches and their variations in 100 cadaveric hands at Dr. D . Y. Patil Medical College, Pune and B.J. Government Medical College, Pune, India. Result and Conclusion: According to Adachi’s classification the most predominant pattern obseved was of Ulnar type arch (66%). According to Coleman and Anson classification 82% showed complete (Group I) superficial palmar arches and a very low incidence (18%) of incomplete arches (Group II). This suggests that collateral circulation is present in majority of cases. This would result in least number of complications considering radial artery harvesting for coronary bypass. Sub-classification of arches according to Coleman and Anson 1961 indicates that the predominant type in the present study was of Group I (Type B) which is formed entirely by Ulnar Artery (56%). Median artery and ulnar artery forming an incomplete superficial arch under Group II (Type C) having an incidence of 4% was recorded. Thus in such cases radial artery harvesting for coronary artery bypass may prove to be less fatal. This study is an effort to provide data about the formation of superficial palmar arches which has been a centre of attraction for most of the surgical procedures and injuries of the hand. PMID:24959427

  7. Chemical Principles Revisited: Chemical Equilibrium.

    ERIC Educational Resources Information Center

    Mickey, Charles D.

    1980-01-01

    Describes: (1) Law of Mass Action; (2) equilibrium constant and ideal behavior; (3) general form of the equilibrium constant; (4) forward and reverse reactions; (5) factors influencing equilibrium; (6) Le Chatelier's principle; (7) effects of temperature, changing concentration, and pressure on equilibrium; and (8) catalysts and equilibrium. (JN)

  8. Response reactions: equilibrium coupling.

    PubMed

    Hoffmann, Eufrozina A; Nagypal, Istvan

    2006-06-01

    It is pointed out and illustrated in the present paper that if a homogeneous multiple equilibrium system containing k components and q species is composed of the reactants actually taken and their reactions contain only k + 1 species, then we have a unique representation with (q - k) stoichiometrically independent reactions (SIRs). We define these as coupling reactions. All the other possible combinations with k + 1 species are the coupled reactions that are in equilibrium when the (q - k) SIRs are in equilibrium. The response of the equilibrium state for perturbation is determined by the coupling and coupled equilibria. Depending on the circumstances and the actual thermodynamic data, the effect of coupled equilibria may overtake the effect of the coupling ones, leading to phenomena that are in apparent contradiction with Le Chatelier's principle.

  9. Thermodynamics "beyond" local equilibrium

    NASA Astrophysics Data System (ADS)

    Vilar, Jose; Rubi, Miguel

    2002-03-01

    Nonequilibrium thermodynamics has shown its applicability in a wide variety of different situations pertaining to fields such as physics, chemistry, biology, and engineering. As successful as it is, however, its current formulation considers only systems close to equilibrium, those satisfying the so-called local equilibrium hypothesis. Here we show that diffusion processes that occur far away from equilibrium can be viewed as at local equilibrium in a space that includes all the relevant variables in addition to the spatial coordinate. In this way, nonequilibrium thermodynamics can be used and the difficulties and ambiguities associated with the lack of a thermodynamic description disappear. We analyze explicitly the inertial effects in diffusion and outline how the main ideas can be applied to other situations. [J.M.G. Vilar and J.M. Rubi, Proc. Natl. Acad. Sci. USA 98, 11081-11084 (2001)].

  10. Computing Equilibrium Chemical Compositions

    NASA Technical Reports Server (NTRS)

    Mcbride, Bonnie J.; Gordon, Sanford

    1995-01-01

    Chemical Equilibrium With Transport Properties, 1993 (CET93) computer program provides data on chemical-equilibrium compositions. Aids calculation of thermodynamic properties of chemical systems. Information essential in design and analysis of such equipment as compressors, turbines, nozzles, engines, shock tubes, heat exchangers, and chemical-processing equipment. CET93/PC is version of CET93 specifically designed to run within 640K memory limit of MS-DOS operating system. CET93/PC written in FORTRAN.

  11. Computing Equilibrium Chemical Compositions

    NASA Technical Reports Server (NTRS)

    Mcbride, Bonnie J.; Gordon, Sanford

    1995-01-01

    Chemical Equilibrium With Transport Properties, 1993 (CET93) computer program provides data on chemical-equilibrium compositions. Aids calculation of thermodynamic properties of chemical systems. Information essential in design and analysis of such equipment as compressors, turbines, nozzles, engines, shock tubes, heat exchangers, and chemical-processing equipment. CET93/PC is version of CET93 specifically designed to run within 640K memory limit of MS-DOS operating system. CET93/PC written in FORTRAN.

  12. 14. BRIDGE ABUTMENT AND ARCH TRUSS MOUNTING PLATE SHOWING EYEBAR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. BRIDGE ABUTMENT AND ARCH TRUSS MOUNTING PLATE SHOWING EYE-BAR CONNECTION AND EYE-BAR PIN LOCATION - Spruce Street Bridge, East Spruce Street, 500 Block, spanning Power Canal, Sault Ste. Marie, Chippewa County, MI

  13. 7. VIEW ACROSS DECK FACING SOUTHWEST; GREAT ARCH IN DISTANCE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. VIEW ACROSS DECK FACING SOUTHWEST; GREAT ARCH IN DISTANCE - Zion-Mount Carmel Highway, Virgin River Bridge, Spanning North Fork of Virgin River on Zion-Mount Carmel Highway, Springdale, Washington County, UT

  14. 19. VIEW ACROSS DECK FACING SOUTHWEST, GREAT ARCH IN DISTANCE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. VIEW ACROSS DECK FACING SOUTHWEST, GREAT ARCH IN DISTANCE - Zion-Mount Carmel Highway, Virgin River Bridge, Spanning North Fork of Virgin River on Zion-Mount Carmel Highway, Springdale, Washington County, UT

  15. 11. DETAIL OF WEST WEB, FROM STREAMBANK, SHOWING ARCH RIB, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. DETAIL OF WEST WEB, FROM STREAMBANK, SHOWING ARCH RIB, HANGERS, FLOOR BEAMS AND GUARDRAIL. VIEW TO NORTHEAST. - Rock Valley Bridge, Spanning North Timber Creek at Old U.S. Highway 30, Marshalltown, Marshall County, IA

  16. 12. DETAIL OF NORTH ABUTMENT, FROM BENEATH, SHOWING ARCH RIB ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. DETAIL OF NORTH ABUTMENT, FROM BENEATH, SHOWING ARCH RIB AND FLOOR BEAM. VIEW TO NORTHEAST. - Rock Valley Bridge, Spanning North Timber Creek at Old U.S. Highway 30, Marshalltown, Marshall County, IA

  17. 11. View looking from opposite direction (N) at arched opening ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. View looking from opposite direction (N) at arched opening depicted in previous view. - Hacienda Azucarera La Esperanza, Mill (Ruins), 2.65 miles North of PR Route 2 Bridge Over Manati River, Manati, Manati Municipio, PR

  18. 19. INTERIOR: ARCH AND CORBELED VAULT NEAR FRONT Copy photograph ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. INTERIOR: ARCH AND CORBELED VAULT NEAR FRONT Copy photograph of photogrammetric plate LC-HABS-GS07-1116-113L. - Provident Life & Trust Company Bank, 407-409 Chestnut Street, Philadelphia, Philadelphia County, PA

  19. Detail of arched corbel table at top of brick privy ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail of arched corbel table at top of brick privy - Central of Georgia Railway, Savannah Repair Shops & Terminal Facilities, Combination Smokestack, Water Tank & Privies, Bounded by West Broad, Jones, West Boundary & Hull Streets, Savannah, Chatham County, GA

  20. 24. Detail view north under bridge showing arched bascule girder, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. Detail view north under bridge showing arched bascule girder, deck girders and cross beams, and bracing of east bascule leaf. - Yellow Mill Bridge, Spanning Yellow Mill Channel at Stratford Avenue, Bridgeport, Fairfield County, CT

  1. Detail, center pier, showing rigidlyfixed arch ribs, starpattern balustrade, and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail, center pier, showing rigidly-fixed arch ribs, star-pattern balustrade, and simple ornamentation including molded treatment of concrete, pyramidal pier cap, and stylized pilaster - Horner Street Bridge, Horner Street over Stonycreek River, Johnstown, Cambria County, PA

  2. DETAIL OF GABLE END WITH ARCHED WINDOW, SHOWING SOFFIT OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL OF GABLE END WITH ARCHED WINDOW, SHOWING SOFFIT OF OVERHANG; CAMERA FACING NORTH - Mare Island Naval Shipyard, Transportation Building & Gas Station, Third Street, south side between Walnut Avenue & Cedar Avenue, Vallejo, Solano County, CA

  3. 13. Detail view of arched opening where fuel was fed ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. Detail view of arched opening where fuel was fed to fire Jamaican Train. - Hacienda Azucarera La Esperanza, Mill (Ruins), 2.65 miles North of PR Route 2 Bridge Over Manati River, Manati, Manati Municipio, PR

  4. DETAIL VIEW, LOOKING WEST, SHOWING ARCH RIB FROM PIER TO ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    DETAIL VIEW, LOOKING WEST, SHOWING ARCH RIB FROM PIER TO PIER, WITH SOUTHERN PACIFIC RAILROAD BRIDGE IN BACKGROUND - Ash Avenue Bridge, Spanning Salt River at Foot of Ash Avenue, Tempe, Maricopa County, AZ

  5. 11. Detail of laminated arch beams, radiators, pews and portion ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Detail of laminated arch beams, radiators, pews and portion of the office to the left of the sanctuary, facing north - Mountain Home Air Force Base, Base Chapel, 350 Willow Street, Cantonment Area, Mountain Home, Elmore County, ID

  6. View of Crane 55 above its arched portal over roadway ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of Crane 55 above its arched portal over roadway atop pier at Drydock No. 2 - Puget Sound Naval Shipyard, Portal Gantry Crane No. 55, Central Industrial Area, Farragut Avenue, Bremerton, Kitsap County, WA

  7. BLDG 2 INTERIOR SHOWING ARCHES IN HALL BY MAIN ENTRY ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    BLDG 2 INTERIOR SHOWING ARCHES IN HALL BY MAIN ENTRY - Naval Magazine Lualualei, Headquarters Branch, Police Station, Kolekole Road & Constitution Street intersection, north side of main quad, Pearl City, Honolulu County, HI

  8. SPRINGING OF THE ARCH, SOUTH END OF BRIDGE, STATEN ISLAND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    SPRINGING OF THE ARCH, SOUTH END OF BRIDGE, STATEN ISLAND SIDE (CONTACT PRINT MADE FROM 5 1/4" X 4 1/2" NEGATIVE) - Bayonne Bridge, Spanning Kill Van Kull between Bayonne & Staten Island, Bayonne, Hudson County, NJ

  9. 41. VIEW EAST OF ARCH AND PASSAGEWAY MARKED '1905' THROUGH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    41. VIEW EAST OF ARCH AND PASSAGEWAY MARKED '1905' THROUGH BUILDING 48; BUILDING 7 IS AT LEFT CENTER, BUILDING 6 IS AT EXTREME RIGHT OF PHOTOGRAPH - Scovill Brass Works, 59 Mill Street, Waterbury, New Haven County, CT

  10. NASA's SDO Watches Magnetic Arches Tower Over Sun's Surface

    NASA Image and Video Library

    Massive arches of solar material brighten and stream over an active region on the sun’s surface in this animation of imagery captured by NASA’s Solar Dynamics Observatory, or SDO, on Sept. 29, 2016...

  11. NASA’s SDO Captures Cascading Magnetic Arches

    NASA Image and Video Library

    A dark solar filament above the sun's surface became unstable and erupted on Dec. 16-17, 2015, generating a cascade of magnetic arches. A small eruption to the upper right of the filament was likel...

  12. 18. Pennsylvania Railroad: Brick Arch Viaduct. Philadelphia, Philadelphia Co., PA. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. Pennsylvania Railroad: Brick Arch Viaduct. Philadelphia, Philadelphia Co., PA. Sec. 1101, MP 87.44. - Northeast Railroad Corridor, Amtrak route between Delaware-Pennsylvania & Pennsylvania-New Jersey state lines, Philadelphia, Philadelphia County, PA

  13. 19. Pennsylvania Railroad: Brick Arch Viaduct. Philadelphia, Philadelphia Co., PA. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. Pennsylvania Railroad: Brick Arch Viaduct. Philadelphia, Philadelphia Co., PA. Sec. 1101, MP 87.44. - Northeast Railroad Corridor, Amtrak route between Delaware-Pennsylvania & Pennsylvania-New Jersey state lines, Philadelphia, Philadelphia County, PA

  14. Oblique view of arches and ironwork on south breezeway ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Oblique view of arches and ironwork on south breezeway - National Home for Disabled Volunteer Soldiers, Pacific Branch, Mental Health Buildings, 11301 Wilshire Boulevard, West Los Angeles, Los Angeles County, CA

  15. 5. LOOKING DUE WEST, THIS ELEVATION SHOWS THE ABUTMENTS, ARCH, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. LOOKING DUE WEST, THIS ELEVATION SHOWS THE ABUTMENTS, ARCH, DECORATED SPANDRELS, THE BALLISTERS AND THE 25' RAISE IN GRADE WHICH WAS ACCOMPLISHED WITH BORROWED FILL. - Vandalia Railroad Bridge, Spanning U.S. Route 40, Indianapolis, Marion County, IN

  16. Detail of windows in arched opening on left of east ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail of windows in arched opening on left of east elevation; camera facing west. - Mare Island Naval Shipyard, Rubber Shop, California Avenue, west side across from Dry Dock 1 near Ninth Street, Vallejo, Solano County, CA

  17. 25. REPRESENTATIVE DETAIL VIEW OF THE TWO ARCHED PEDESTRIAN BRIDGES ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    25. REPRESENTATIVE DETAIL VIEW OF THE TWO ARCHED PEDESTRIAN BRIDGES OVER THE CANALS, SHOWING PLANKS AND RAILS. THIS BRIDGE IS THE LINNIE CANAL COURT BRIDGE OVER EASTERN CANAL. - Venice Canals, Community of Venice, Los Angeles, Los Angeles County, CA

  18. 4. Detail view of brick arch above doorway on W ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. Detail view of brick arch above doorway on W wall of Blacksmith Shop. - Central of Georgia Railway, Savannah Repair Shops & Terminal Facilities, Blacksmith Shop, Bounded by West Broad, Jones, West Boundary & Hull Streets, Savannah, Chatham County, GA

  19. Cellar: Detail of paired relieving arch and remains of herringbone ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Cellar: Detail of paired relieving arch and remains of herringbone brick pattern from earlier cooking fireplace at back, southeast wall looking southeast - Kingston-Upon-Hill, Kitts Hummock Road, Dover, Kent County, DE

  20. 41. DETAIL OF DOUBLE WINDOW ELEMENT WITH ARCHED BRICK PATTERN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    41. DETAIL OF DOUBLE WINDOW ELEMENT WITH ARCHED BRICK PATTERN ON EAST SIDE OF 1931 SECTION, TAKEN FROM THE EAST. - James Russell Lowell Elementary School, 4501 Crittenden Drive, Louisville, Jefferson County, KY

  1. Halfcellar underneath original house showing fireplace relieving arch at northwest ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Half-cellar underneath original house showing fireplace relieving arch at northwest end; enclosed "cheese" room to right - Scheetz Farm, House, 7161 Camp Hill Road, Fort Washington, Montgomery County, PA

  2. 57. Metz Run Viaduct. Detail of the reinforced concrete arched ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    57. Metz Run Viaduct. Detail of the reinforced concrete arched piers. Looking south-southeast. - Blue Ridge Parkway, Between Shenandoah National Park & Great Smoky Mountains, Asheville, Buncombe County, NC

  3. 16. TAILRACE ARCH FROM 1814 MILL BROKEN THROUGH DURING EXCAVATION ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    16. TAILRACE ARCH FROM 1814 MILL BROKEN THROUGH DURING EXCAVATION FOR A SURFACE WATER RUNOFF POLLUTION TRAP, SUBSEQUENTLY FILLED. - Boston Manufacturing Company, 144-190 Moody Street, Waltham, Middlesex County, MA

  4. Arch construction at south end, looking east with Phoenix Iron ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Arch construction at south end, looking east with Phoenix Iron Company foundry in background. - Gay Street Bridge, Spanning French Creek at Gay Street (State Route 113), Phoenixville, Chester County, PA

  5. 8. VIEW NORTHWEST OF EAST ELEVATION SOUTH BARREL ARCH. NOTE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. VIEW NORTHWEST OF EAST ELEVATION SOUTH BARREL ARCH. NOTE STONE WORK, 1920 CONCRETE REPAIRS, AND STEEL BRACES ADDED BY THE NATIONAL PARK SERVICE CIRCA 1962. - Chesapeake & Ohio Canal, Conococheague Creek Aqueduct, Milepost 99.80, Williamsport, Washington County, MD

  6. 5. DETAIL VIEW OF PORTION OF EAST ELEVATION SHOWING ARCHED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. DETAIL VIEW OF PORTION OF EAST ELEVATION SHOWING ARCHED WINDOW AND DOOR OPENINGS - Presidio Water Treatment Plant, Filtration Plant, East of Lobos Creek at Baker Beach, San Francisco, San Francisco County, CA

  7. Close view of the Constitution Avenue elevation to show arched ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Close view of the Constitution Avenue elevation to show arched gateways and pedimented pavilion ("Commerce and Communication" sculpted pediment) - Interstate Commerce Commission, Constitution Avenue between Twelfth and Fourteenth streets, Washington, District of Columbia, DC

  8. LOOKING WEST, BETWEEN READING DEPOT BRIDGE AND SKEW ARCH BRIDGE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    LOOKING WEST, BETWEEN READING DEPOT BRIDGE AND SKEW ARCH BRIDGE (HAER No. PA-116). - Philadelphia & Reading Railroad, Reading Depot Bridge, North Sixth Street at Woodward Street, Reading, Berks County, PA

  9. 3. DETAIL OF STONEWORK ON ARCH, WATER TABLE AND DENTILS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. DETAIL OF STONEWORK ON ARCH, WATER TABLE AND DENTILS ON EAST ELEVATION LOOKING NORTHWEST. - Original Airport Entrance Overpass, Spanning original Airport Entrance Road at National Airport, Arlington, Arlington County, VA

  10. 4. ELEVATION OF WESTERN ARCHES OVER STATE ROUTE 611 AND ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. ELEVATION OF WESTERN ARCHES OVER STATE ROUTE 611 AND RAILROAD TRACKS, FROM SOUTH. - Delaware, Lackawanna & Western Railroad, Delaware River Viaduct, Spanning Delaware River, north of Portland-Columbia Bridge, Portland, Northampton County, PA

  11. 2. ELEVATION OF TYPICAL ARCH OF VIADUCT, FROM SOUTH. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. ELEVATION OF TYPICAL ARCH OF VIADUCT, FROM SOUTH. - Delaware, Lackawanna & Western Railroad, Delaware River Viaduct, Spanning Delaware River, north of Portland-Columbia Bridge, Portland, Northampton County, PA

  12. 18. INTERIOR: ARCH AND COLUMN NEAR FRONT Copy photograph of ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. INTERIOR: ARCH AND COLUMN NEAR FRONT Copy photograph of photogrammetric plate LC-HABS-GS07-1116-112L. - Provident Life & Trust Company Bank, 407-409 Chestnut Street, Philadelphia, Philadelphia County, PA

  13. View from inside Train Shed looking out through arched opening. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View from inside Train Shed looking out through arched opening. - Central of Georgia Railway, Passenger Station & Train Shed, Corner of Louisville (Railroad) Road & West Broad Street, Savannah, Chatham County, GA

  14. Detail of arch opening on N elevation of Train Shed. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail of arch opening on N elevation of Train Shed. - Central of Georgia Railway, Passenger Station & Train Shed, Corner of Louisville (Railroad) Road & West Broad Street, Savannah, Chatham County, GA

  15. Arch opening on N elevation as seen from inside Train ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Arch opening on N elevation as seen from inside Train Shed, - Central of Georgia Railway, Passenger Station & Train Shed, Corner of Louisville (Railroad) Road & West Broad Street, Savannah, Chatham County, GA

  16. 12. INTERIOR: ARCH (JUNCTION OF TRANSVERSE AND MAIN HALLS) Copy ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. INTERIOR: ARCH (JUNCTION OF TRANSVERSE AND MAIN HALLS) Copy photograph of photogrammetric plate LC-HABS-GS07-T-935-511L. - Stanbery-Rising House, High Street, at corner of Wheeling Street, Lancaster, Fairfield County, OH

  17. ABUTMENT. NOTE HOW ARCHES BUTT AGAINST A CONCRETE PAD ADDED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    ABUTMENT. NOTE HOW ARCHES BUTT AGAINST A CONCRETE PAD ADDED IN 1968. NOTE ALSO IRON TIE ROD AT LOWER CHORD. - Dreibelbis Station Bridge, Spanning Maiden Creek, Balthaser Road (TR 745), Lenhartsville, Berks County, PA

  18. 22. Detail view of arched passageway as in preceeding photo. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    22. Detail view of arched passageway as in preceeding photo. - Hacienda Azurarera Santa Elena, Sugar Mill Ruins, 1.44 miles North of PR Route 2 Bridge Over Rio De La Plata, Toa Baja, Toa Baja Municipio, PR

  19. 23. Detail view of brickwork in same arched passageway. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. Detail view of brickwork in same arched passageway. - Hacienda Azurarera Santa Elena, Sugar Mill Ruins, 1.44 miles North of PR Route 2 Bridge Over Rio De La Plata, Toa Baja, Toa Baja Municipio, PR

  20. 80. LITTLE ROCK DAM: DIMENSIONS, SECTION THROUGH ARCH RING, AMENDED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    80. LITTLE ROCK DAM: DIMENSIONS, SECTION THROUGH ARCH RING, AMENDED SHEET 5; SEPTEMBER, 1922. Palmdale Water District files. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

  1. PERSPECTIVE OF UNDERSIDE SHOWING ARCHED GIRDER AND SLAB CONSTRUCTION. NOTE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    PERSPECTIVE OF UNDERSIDE SHOWING ARCHED GIRDER AND SLAB CONSTRUCTION. NOTE TWISTED BAR STOCK REINFORCING CAN BE SEEN. - Keggereis Ford Bridge, Spanning West Branch Conococheague Creek at State Route 4006, Willow Hill, Franklin County, PA

  2. 18. SECOND FLOOR, CITY COMMISSION CHAMBERS, DETAIL OF ARCH WITH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. SECOND FLOOR, CITY COMMISSION CHAMBERS, DETAIL OF ARCH WITH MURAL ON LEFT OF BENCH, SHOWING SEAMEN,SCIENTIST,SPORTSMEN AND STATE SEAL - City Hall, Atlantic & Tennessee Avenues, Atlantic City, Atlantic County, NJ

  3. Detail view of keystone sculpted head in the arched passage ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail view of keystone sculpted head in the arched passage to the lobby vestibule - United States Department of Commerce, Bounded by Fourteenth, Fifteenth, and E streets and Constitution Avenue, Washington, District of Columbia, DC

  4. 28. 'Details Of Abutments For Three Hinged Arch Bridge Over ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    28. 'Details Of Abutments For Three Hinged Arch Bridge Over Yuba River, Thomas System, Thomas And Post, Engineers, Hibernian Bldg., Los Angeles,' dated March 31, 1913. - Parks Bar Bridge, Spanning Yuba River at State Highway 20, Smartville, Yuba County, CA

  5. 31. 'Details For Three Hinged Arch Bridge Over Yuba River, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    31. 'Details For Three Hinged Arch Bridge Over Yuba River, Thomas System, Thomas And Post--Consulting Engineers, Hibernian Bldg., Los Angeles, Revised Oct. 22, 1912.' - Parks Bar Bridge, Spanning Yuba River at State Highway 20, Smartville, Yuba County, CA

  6. 1. South elevation, (lr) arches CD and DE. View north ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. South elevation, (l-r) arches C-D and D-E. View north - Ashton Viaduct, State Route 116 (Washington Highway) spanning Blackstone River, Blackstone Canal, & Providence & Worcester Railroad, Ashton, Providence County, RI

  7. 7. (lr) Arches DE, CD, BC. View southwest Ashton ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. (l-r) Arches D-E, C-D, B-C. View southwest - Ashton Viaduct, State Route 116 (Washington Highway) spanning Blackstone River, Blackstone Canal, & Providence & Worcester Railroad, Ashton, Providence County, RI

  8. 5. Railroad tracks, (lr) arches EF, DE, CD, BC. View ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. Railroad tracks, (l-r) arches E-F, D-E, C-D, B-C. View southwest - Ashton Viaduct, State Route 116 (Washington Highway) spanning Blackstone River, Blackstone Canal, & Providence & Worcester Railroad, Ashton, Providence County, RI

  9. 6. (1r) Arches EF, DE. View southeast Ashton Viaduct, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. (1-r) Arches E-F, D-E. View southeast - Ashton Viaduct, State Route 116 (Washington Highway) spanning Blackstone River, Blackstone Canal, & Providence & Worcester Railroad, Ashton, Providence County, RI

  10. 5. BUILDING 0503, INTERIOR WOODEN ARCHES. Looking south from entrance. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. BUILDING 0503, INTERIOR WOODEN ARCHES. Looking south from entrance. - Edwards Air Force Base, South Base Sled Track, Earth Covered Bunker Types, North of Sled Track, Lancaster, Los Angeles County, CA

  11. 1. VIEW SOUTHWARD FROM SOUTHWEST CORNER FRONT AND ARCH STREETS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. VIEW SOUTHWARD FROM SOUTHWEST CORNER FRONT AND ARCH STREETS (2. N. Front Street starts at left) - North Front Street Area Study, 2-66 North Front Street (Commercial Buildings), Philadelphia, Philadelphia County, PA

  12. Detail view highlighting the series of pointed arch windows along ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail view highlighting the series of pointed arch windows along the North Carrollton facade - Reformed Episcopal Church of the Rock of Ages, 1210 West Lanvale Street, Baltimore, Independent City, MD

  13. 65. Close up view of downstream face of arch, buttress ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    65. Close up view of downstream face of arch, buttress ties and roadway support work. Photographer Mark Durben. Source: Salt River Project. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

  14. 23. Upstream view of buttress and arch form work and ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    23. Upstream view of buttress and arch form work and construction. Photographer unknown, 1927. Source: MWD. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

  15. 19. Upstream face of arches and buttresses at west end. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. Upstream face of arches and buttresses at west end. Photographer unknown, January 29, 1927. Source: MWD. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

  16. 36. DETAIL, ALTERNATE DESIGN USING THROUGH ARCH SPANS Pencil drawing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    36. DETAIL, ALTERNATE DESIGN USING THROUGH ARCH SPANS Pencil drawing by project architect Alfred Eichler, ca. 1934. - Sacramento River Bridge, Spanning Sacramento River at California State Highway 275, Sacramento, Sacramento County, CA

  17. 198. SPOUT RUN ARCH BRIDGE AND SPOUT RUN WESTBOUND BRIDGE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    198. SPOUT RUN ARCH BRIDGE AND SPOUT RUN WESTBOUND BRIDGE FROM POTOMAC RIVER LOOKING SOUTHWEST. - George Washington Memorial Parkway, Along Potomac River from McLean to Mount Vernon, VA, Mount Vernon, Fairfax County, VA

  18. Arch development with trans-force lingual appliances.

    PubMed

    Clark, William J

    2005-01-01

    Trans-Force lingual appliances are designed to correct arch form in patients with contracted dental arches. Interceptive treatment with this new series of pre-activated lingual appliances offers new possibilities for arch development, in combination with fixed appliances. Palatal and lingual appliances insert in horizontal lingual sheaths in molar bands. No activation is required after the appliance is fitted, and this principle is extended to a series of appliances for sagittal and transverse arch development. Both sagittal and transverse appliances have additional components to achieve 3-way expansion where this is indicated. The invisible lingual appliances may be used in correction of all classes of malocclusion at any stage of development, from mixed dentition through permanent dentition, and this approach has wide indications in adult treatment.

  19. Detail, southwest arch rib, hangers, and portion of portal braces, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail, southwest arch rib, hangers, and portion of portal braces, from southeast, showing simple ornamentation, including molded treatment of concrete and recessed panels - Horner Street Bridge, Horner Street over Stonycreek River, Johnstown, Cambria County, PA

  20. Detail southeast arch rib, hangers, and portion of portal frame, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail southeast arch rib, hangers, and portion of portal frame, from southwest, showing simple ornamentation, including molded treatment of concrete and recessed panels - Horner Street Bridge, Horner Street over Stonycreek River, Johnstown, Cambria County, PA

  1. 5. DETAIL VIEW OF JUNCTURE BETWEEN ARCH, AND ABUTMENT, SHOWING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    5. DETAIL VIEW OF JUNCTURE BETWEEN ARCH, AND ABUTMENT, SHOWING CANTILEVERED WALKWAY AND DECK BEAMS ON UNDERSIDE OF BRIDGE - Benson Street Concrete Bowstring Bridge, Spanning Mill Creek at Benson Street, Lockland, Hamilton County, OH

  2. 4. SIDE VIEW OF BRIDGE, LOOKING SOUTHWEST, SHOWING ARCHES, CANTILEVERED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. SIDE VIEW OF BRIDGE, LOOKING SOUTHWEST, SHOWING ARCHES, CANTILEVERED WALKWAY, DECK BEAMS AND STREAMBED - Benson Street Concrete Bowstring Bridge, Spanning Mill Creek at Benson Street, Lockland, Hamilton County, OH

  3. 90. VIEW OF THE HEAD ARCHES AND FAIRMOUNT POND, CA. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    90. VIEW OF THE HEAD ARCHES AND FAIRMOUNT POND, CA. 1875 Collection of the Fairmount Park Commission - Fairmount Waterworks, East bank of Schuylkill River, Aquarium Drive, Philadelphia, Philadelphia County, PA

  4. 19. SECOND FLOOR, CITY COMMISSION CHAMBERS, DETAIL OF ARCH WITH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. SECOND FLOOR, CITY COMMISSION CHAMBERS, DETAIL OF ARCH WITH MURAL ON RIGHT OF BENCH, SHOWING PIONEERS AND ATLANTIC CITY SEAL - City Hall, Atlantic & Tennessee Avenues, Atlantic City, Atlantic County, NJ

  5. 19. COPY OF ENGRAVING OF 'WROUGHT IRON ARCH TRUSS BRIDGE,' ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. COPY OF ENGRAVING OF 'WROUGHT IRON ARCH TRUSS BRIDGE,' PAT. DEC. 10, 1867 BY OHIO BRIDGE COMPANY, CLEVELAND, OHIO. (COURTESY OF OHIO HISTORICAL SOCIETY ARCHIVES, COLUMBUS, OHIO) - Tioronda Bridge, South Avenue spanning Fishkill Creek, Beacon, Dutchess County, NY

  6. 22. DETAIL, WEST ABUTMENT AND SHOE, WEST ARCH, UPSTREAM SIDE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    22. DETAIL, WEST ABUTMENT AND SHOE, WEST ARCH, UPSTREAM SIDE File photo, Caltrans Office of Structures Maintenance, August, 1953. Photographer unknown. Photocopy of photograph. - San Roque Canyon Bridge, State Highway 192, Santa Barbara, Santa Barbara County, CA

  7. 22. STEEL ARCH SEGMENT AND VENT IN OFFICE, ROOM 2351, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    22. STEEL ARCH SEGMENT AND VENT IN OFFICE, ROOM 2351, SECOND FLOOR, NORTH SIDE. - Hughes Aircraft Company, Processing & Electronics Building, 6775 Centinela Avenue, Los Angeles, Los Angeles County, CA

  8. 9. DETAIL (WITH SCALE) OF CLOSED SPANDREL CONCRETE ARCH, ABUTMENT, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. DETAIL (WITH SCALE) OF CLOSED SPANDREL CONCRETE ARCH, ABUTMENT, RAILINGS AND ENDPOST; VIEW TO WEST. - Pleasants Valley Road Bridge, Spanning Pleasants Creek at Pleasants Valley Road, Vacaville, Solano County, CA

  9. View of south entrance to #157 through south breezeway arches ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of south entrance to #157 through south breezeway arches - National Home for Disabled Volunteer Soldiers, Pacific Branch, Mental Health Buildings, 11301 Wilshire Boulevard, West Los Angeles, Los Angeles County, CA

  10. 25. DETAIL OF THE MASONRY ARCH OF A RECTANGULAR COKE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    25. DETAIL OF THE MASONRY ARCH OF A RECTANGULAR COKE OVEN. - Tower Hill No. 2 Mine, Approximately 0.47 mile Southwest of intersection of Stone Church Road & Township Route 561, Hibbs, Fayette County, PA

  11. 7. VAL CONCRETE 'A' FRAME STRUCTURE SHOWING CAMERA TOWER ARCHED ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. VAL CONCRETE 'A' FRAME STRUCTURE SHOWING CAMERA TOWER ARCHED OPENING FOR ROADWAY AND COUNTERWEIGHT SLOPE TAKEN FROM RESERVOIR LOOKING WEST. - Variable Angle Launcher Complex, Variable Angle Launcher, CA State Highway 39 at Morris Reservior, Azusa, Los Angeles County, CA

  12. Age changes in dental arch dimensions of Australian Aboriginals.

    PubMed

    Brown, T; Abbott, A H; Burgess, V B

    1983-11-01

    Breadths and depths of the dental arches were measured from standardized photographs of serial casts of Australian Aboriginals enrolled in a longitudinal growth study. The data were obtained from 1161 sets of casts representing 111 boys and 86 girls ranging in age from 6 to 19 years. Age changes in the arch dimensions conformed to previously described patterns in Caucasian children, namely, an increase in breadth and a decrease in depth. Corresponding dimensions and dimensional changes in the maxilla and mandible were strongly correlated, but breadth and depth changes were relatively independent. The disparity in size between arches increased with age, particularly in the breadth dimension of boys. Marked disparity in arch breadths characterizes an occlusal feature of this population that has been termed alternate intercuspation.

  13. 1. Elkmont vehicle bridge at Elkmont Campground, galvanized corrugated arch. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Elkmont vehicle bridge at Elkmont Campground, galvanized corrugated arch. - Great Smoky Mountains National Park Roads & Bridges, Elkmont Vehicle Bridge, Spanning Little River at Elkmont Campground, Gatlinburg, Sevier County, TN

  14. The azygous arch: normal and pathologic CT appearance

    SciTech Connect

    Smathers, R.L.; Buschi, A.J.; Pope, T.L. Jr.; Brenbridge, A.N.; Williamson, B.R.

    1982-09-01

    The arch of the azygous vein, a commonly identified anatomic landmark on contrast-enhanced computed tomographic (CT) scans of the chest, forms the lateral boundary of the pretracheal-retrocaval space and, with its pleural reflections, demarcates the mediastinum from the right lung. Normal variations, congenital anomalies, vascular lesions, adenopathy, neoplasm, and mediastinitis alter the position, size contour, and flow patterns of the azygous venous arch. Mass lesions may displace the arch laterally when they arise from the mediastinum or medially when they arise from the right lung. Malignancies, either primary or secondary, can invade, obstruct, or obliterate it. Abnormal flow patterns can be identified due to caval obstruction or pericardial disease. Awareness of the variability of the CT appearance of the azygous arch and its alteration by disease increases the utility of CT in the analysis of mediastinal and pulmonary pathology.

  15. Detail view of bracket, arched window and eagle from building ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail view of bracket, arched window and eagle from building 18 section. Jet Lowe, Haer staff photographer, summer 1995 - Naval Base Philadelphia-Philadelphia Naval Shipyard, Machine Shops, League Island, Philadelphia, Philadelphia County, PA

  16. Arch & Chord Joint Detail; Crossbracing Center Joint Detail; Chord, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Arch & Chord Joint Detail; Crossbracing Center Joint Detail; Chord, Panel Post, Tie & Diagonal Brace Joint Detail; Chord, Panel Post, Tie & Crossbracing Joint Detail - Dunlapsville Covered Bridge, Spanning East Fork Whitewater River, Dunlapsville, Union County, IN

  17. 84. AERIAL VIEW OF SPOUT RUN ARCH BRIDGE, SPOUT RUN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    84. AERIAL VIEW OF SPOUT RUN ARCH BRIDGE, SPOUT RUN BRIDGE WESTBOUND AND SPOUT RUN PARKWAY CULVERT LOOKING SOUTH. - George Washington Memorial Parkway, Along Potomac River from McLean to Mount Vernon, VA, Mount Vernon, Fairfax County, VA

  18. 87. AERIAL VIEW OF SPOUT RUN ARCH BRIDGE, SPOUT RUN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    87. AERIAL VIEW OF SPOUT RUN ARCH BRIDGE, SPOUT RUN BRIDGE WESTBOUND AND SPOUT RUN PARKWAY CULVERT LOOKING SOUTHWEST. - George Washington Memorial Parkway, Along Potomac River from McLean to Mount Vernon, VA, Mount Vernon, Fairfax County, VA

  19. 86. AERIAL VIEW OF SPOUT RUN ARCH BRIDGE, SPOUT RUN ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    86. AERIAL VIEW OF SPOUT RUN ARCH BRIDGE, SPOUT RUN BRIDGE WESTBOUND AND SPOUT RUN PARKWAY CULVERT LOOKING SOUTH. - George Washington Memorial Parkway, Along Potomac River from McLean to Mount Vernon, VA, Mount Vernon, Fairfax County, VA

  20. 11. DETAIL VIEW OF NORTH ELEVATION ARCH AND WING WALL ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. DETAIL VIEW OF NORTH ELEVATION ARCH AND WING WALL AT JUNCTURE WITH PEDESTRIAN BRIDGE, LOOKING SOUTHWEST - Lake Street Bridge, Spanning Ruddiman Creek at Lake Shore Drive, Muskegon, Muskegon County, MI

  1. Perspective of east arch section, showing five panels made up ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Perspective of east arch section, showing five panels made up of diagonal suspension ribs and vertical ribs. The abutments, piers, wing walls, coping and deck are of concrete. - Weaverland Bridge, Quarry Road spanning Conestoga Creek, Terre Hill, Lancaster County, PA

  2. 8. Detail view of pierced arch concrete rails and recessed ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    8. Detail view of pierced arch concrete rails and recessed panel railing piers at the west pedestrian alcove, north side of the bridge. - Yellow Mill Bridge, Spanning Yellow Mill Channel at Stratford Avenue, Bridgeport, Fairfield County, CT

  3. Growth and hemodynamics after early embryonic aortic arch occlusion*

    PubMed Central

    Lindsey, Stephanie E.; Menon, Prahlad G.; Kowalski, William J.; Shekhar, Akshay; Yalcin, Huseyin C.; Nishimura, Nozomi; Schaffer, Chris B.; Butcher, Jonathan T.; Pekkan, Kerem

    2015-01-01

    The majority of severe clinically significant forms of congenital heart disease (CHD) is associated with great artery lesions, including hypoplastic, double, right or interrupted aortic arch morphologies. While fetal and neonatal interventions are advancing, their potential ability to restore cardiac function, optimal timing, location, and intensity required for intervention remain largely unknown. We here combine computational fluid dynamics (CFD) simulations with in vivo experiments to test how individual pharyngeal arch artery hemodynamics alters as a result of local interventions to obstruct individual arch artery flow. Simulated isolated occlusions within each pharyngeal arch artery were created with image derived three-dimensional (3D) reconstructions of normal chick pharyngeal arch anatomy at Hamburger-Hamilton (HH) developmental stages HH18 and HH24. Acute flow redistributions were then computed using in vivo measured subject-specific aortic sinus inflow velocity profiles. A kinematic vascular growth-rendering algorithm was then developed and implemented to test the role of changing local wall shear stress patterns in downstream 3D morphogenesis of arch arteries. CFD simulations predicted that altered pressure gradients and flow redistributions were most sensitive to occlusion of the IVth arches. To evaluate these simulations experimentally, a novel in vivo experimental model of pharyngeal arch occlusion was developed and implemented using two-photon microscopy guided femtosecond laser based photodisruption surgery. The right IVth arch was occluded at HH18, and resulting diameter changes were followed for up to 24 hours. Pharyngeal arch diameter responses to acute hemodynamic changes were predicted qualitatively but poorly quantitatively. Chronic growth and adaptation to hemodynamic changes however were predicted in a subset of arches. Our findings suggest that this complex biodynamic process is governed through more complex forms of mechanobiological

  4. Growth and hemodynamics after early embryonic aortic arch occlusion.

    PubMed

    Lindsey, Stephanie E; Menon, Prahlad G; Kowalski, William J; Shekhar, Akshay; Yalcin, Huseyin C; Nishimura, Nozomi; Schaffer, Chris B; Butcher, Jonathan T; Pekkan, Kerem

    2015-08-01

    The majority of severe clinically significant forms of congenital heart disease (CHD) are associated with great artery lesions, including hypoplastic, double, right or interrupted aortic arch morphologies. While fetal and neonatal interventions are advancing, their potential ability to restore cardiac function, optimal timing, location, and intensity required for intervention remain largely unknown. Here, we combine computational fluid dynamics (CFD) simulations with in vivo experiments to test how individual pharyngeal arch artery hemodynamics alter as a result of local interventions obstructing individual arch artery flow. Simulated isolated occlusions within each pharyngeal arch artery were created with image-derived three-dimensional (3D) reconstructions of normal chick pharyngeal arch anatomy at Hamburger-Hamilton (HH) developmental stages HH18 and HH24. Acute flow redistributions were then computed using in vivo measured subject-specific aortic sinus inflow velocity profiles. A kinematic vascular growth-rendering algorithm was then developed and implemented to test the role of changing local wall shear stress patterns in downstream 3D morphogenesis of arch arteries. CFD simulations predicted that altered pressure gradients and flow redistributions were most sensitive to occlusion of the IVth arches. To evaluate these simulations experimentally, a novel in vivo experimental model of pharyngeal arch occlusion was developed and implemented using two-photon microscopy-guided femtosecond laser-based photodisruption surgery. The right IVth arch was occluded at HH18, and resulting diameter changes were followed for up to 24 h. Pharyngeal arch diameter responses to acute hemodynamic changes were predicted qualitatively but poorly quantitatively. Chronic growth and adaptation to hemodynamic changes, however, were predicted in a subset of arches. Our findings suggest that this complex biodynamic process is governed through more complex forms of mechanobiological

  5. [Intraparotid first branchial arch cyst: complex diagnostic and therapeutic process].

    PubMed

    Gilabert Rodríguez, R; Berenguer, B; González Meli, B; Marín Molina, C; de Tomás Palacios, E; Buitrago Weiland, G; Aguado del Hoyo, A

    2013-01-01

    First branchial arch cysts are uncommon. Therefore, together with its variable clinical and age presentation they are often misdiagnosed at first. The treatment is surgical, requiring a correct procedure to avoid future recurrences. In this paper we describe a typical case of first branchial arch cyst in which as described in other reports, we first made several misdiagnoses and therefore an inadequate treatment and lastly, with the correct diagnosis, we performed a meticulous complete excision under facial nerve monitoring.

  6. The mathematical model of the chevron-arch gearing transmitter

    NASA Astrophysics Data System (ADS)

    Bubenchikov, Aleksey; Bubenchikov, Mikhail; Matvienko, Oleg; Shcherbakov, Nikolay

    2016-01-01

    The teeth of herringbone transmission wheels are obtained by docking two helical wheels with an opposite arrangement of teeth, which can solve the problem of the axial force. The mathematical model of coupling chevron teeth of the driving wheel in the area of their docking using the arch tooth fragment is developed. The conjugacy area surface of the driven wheel chevron teeth is obtained as the envelope of the surfaces family formed by the arched tooth during the process of the parts motion.

  7. Clarifying the anatomy of the fifth arch artery

    PubMed Central

    Gupta, Saurabh Kumar; Gulati, Gurpreet Singh; Anderson, Robert H

    2016-01-01

    The artery allegedly forming in the fifth pharyngeal arch has increasingly been implicated as responsible for various vascular malformations in patients with congenitally malformed hearts. Observations from studies on developing embryos, however, have failed to provide support to substantiate several of these inferences such that the very existence of the fifth arch artery remains debatable. To the best of our knowledge, in only a solitary human embryo has a vascular channel been found that truly resembled the artery of the fifth arch. Despite the meager evidence to support its existence, the fifth arch artery has been invoked to explain the morphogenesis of double-barreled aorta, some unusual forms of aortopulmonary communications, and abnormalities of the brachiocephalic arteries. In most of these instances, the interpretations have proved fallible when examined in the light of existing knowledge of cardiac development. In our opinion, there are more plausible alternative explanations for the majority of these descriptions. Double-barreled aorta is more likely to result from retention of the recently identified dorsal collateral channels while abnormalities of brachiocephalic arteries are better explained on the basis of extensive remodeling of aortic arches during fetal development. Some examples of aortopulmonary communications, nonetheless, may well represent persistence of the developing artery of the fifth pharyngeal arch. We here present one such case — a patient with tetralogy of Fallot and pulmonary atresia, in whom the fifth arch artery provided a necessary communication between the ascending aorta and the pulmonary arteries. In this light, we discuss the features we consider to be essential before attaching the tag of “fifth arch artery” to a candidate vascular channel. PMID:27011696

  8. NASA ARCH- A FILE ARCHIVAL SYSTEM FOR THE DEC VAX

    NASA Technical Reports Server (NTRS)

    Scott, P. J.

    1994-01-01

    The function of the NASA ARCH system is to provide a permanent storage area for files that are infrequently accessed. The NASA ARCH routines were designed to provide a simple mechanism by which users can easily store and retrieve files. The user treats NASA ARCH as the interface to a black box where files are stored. There are only five NASA ARCH user commands, even though NASA ARCH employs standard VMS directives and the VAX BACKUP utility. Special care is taken to provide the security needed to insure file integrity over a period of years. The archived files may exist in any of three storage areas: a temporary buffer, the main buffer, and a magnetic tape library. When the main buffer fills up, it is transferred to permanent magnetic tape storage and deleted from disk. Files may be restored from any of the three storage areas. A single file, multiple files, or entire directories can be stored and retrieved. archived entities hold the same name, extension, version number, and VMS file protection scheme as they had in the user's account prior to archival. NASA ARCH is capable of handling up to 7 directory levels. Wildcards are supported. User commands include TEMPCOPY, DISKCOPY, DELETE, RESTORE, and DIRECTORY. The DIRECTORY command searches a directory of savesets covering all three archival areas, listing matches according to area, date, filename, or other criteria supplied by the user. The system manager commands include 1) ARCHIVE- to transfer the main buffer to duplicate magnetic tapes, 2) REPORTto determine when the main buffer is full enough to archive, 3) INCREMENT- to back up the partially filled main buffer, and 4) FULLBACKUP- to back up the entire main buffer. On-line help files are provided for all NASA ARCH commands. NASA ARCH is written in DEC VAX DCL for interactive execution and has been implemented on a DEC VAX computer operating under VMS 4.X. This program was developed in 1985.

  9. Cost of skid roads for arch logging in West Virginia

    Treesearch

    George R., Jr. Trimble; Carl R. Barr

    1960-01-01

    In the mountain hardwood country of the northern Appalachians, tree-length skidding with tractor and arch has proved to be economical logging. One essential part of this type of logging is that tree-length logs are winched to the skid roads: tractor and arch do not run around through the woods. Winching distance is commonly 200 to 300 feet; and occasionally an extra...

  10. Aortic coarctation with persistent fifth left aortic arch.

    PubMed

    Santoro, Giuseppe; Caianiello, Giuseppe; Palladino, Maria Teresa; Iacono, Carola; Russo, Maria Giovanna; Calabrò, Raffaele

    2009-08-14

    A neonate with severe aortic coarctation showed a double lumen transverse aorta (persistent fifth aortic arch) with both channels joining at the isthmus where the obstruction was confirmed by echocardiography and cardiac catheterization. Surgical repair was performed with a pantaloon-shaped patch. Persistent fifth aortic arch does not result in a vascular ring and, per se, is not hemodynamically significant unless associated with other cardiac malformations.

  11. [Application of modified traction arch of skull in skull traction].

    PubMed

    Lei, Xing; Wang, Huan; Song, Yang; Qu, Yanlong

    2014-12-01

    To investigate the feasibility and effectiveness of the modified traction arch of skull (crossbar traction arch) for skull traction in treating cervical spine injury by comparing with traditional traction arch of skull. Between June 2009 and June 2013, 90 patients with cervical vertebrae fractures or dislocation were treated with modified skull traction surgery (trial group, n=45) and traditional skull traction surgery (control group, n=45). There was no significant difference in gender, age, injury types, injury level, the interval between injury and admission, and Frankel grading of spinal injury between 2 groups (P > 0.05). The clinical efficacy was evaluated after operation by the indexes such as traction arch slippage times, operation time, the infection incidence of the pin hole, incidence of skull perforation, visual analogue scale (VAS), and reduction status of cervical dislocation. The traction arch slippage times, the infection incidence of the pin hole, operation time, blood loss, and postoperative VAS score in trial group were significantly lower than those in control group (P < 0.05). There was no significant difference in the incidence of skull perforation caused by clamp crooks of traction arch between 2 groups (P=1.000). At 2 weeks after operation, the patients had no headaches, infections, or other complications in 2 groups. In patients with cervical dislocation, 4 of the trial group and 6 of the control group failed to be reset, the reduction rate was 83.33% (20/24) and 68.42% (13/19) respectively, showing no significant difference (χ2=0.618, P=0.432). The operation with modified traction arch of skull has significant advantages to reduce postoperative complication compared with tradition traction arch of skull.

  12. Investigation of complete dental arches of 23 patients aged at least 75 years

    PubMed Central

    Volpato, Beniamino; Di Carlo, Stefano; Shahinas, Jorida; Mencio, Francesca; Fusco, Raimondo; Pompa, Giorgio

    2012-01-01

    Summary Numerous factors help to conserve the dentition of elderly patients, such as healthy food habits, a strong physical constitution, and a good quality of life. The aim of this study was to define a model that takes into account the integration of both the structural and functional aspects of a healthy dentition. Twenty-three patients aged at least 75 years were recruited. The patients were required to possess all of their dentition and have no prosthetic rehabilitations and be asymptomatic for temporomandibular joint disorders. Occlusal characteristics were measured and recorded using the criteria adopted by the US National Health and Nutrition Examination Survey: presence or absence of rotation of the upper arches, trend of the occlusal table, and distribution of occlusal contacts during movements. We believe that the following parameters are predictive of a condition of the dental arches’ equilibrium: crowding and disalignment of the teeth, derotated position of the upper arches, absence of the curve of Spee, an occlusal plane trend contrary to spherical theory, and presence of group function on the working side and malocclusion on the nonworking side. We consider that these factors are merely the consequence of correct functioning within the framework of favorable environmental factors. PMID:22545185

  13. Time-dependent behavior of layered arches with viscoelastic interlayers

    NASA Astrophysics Data System (ADS)

    Wu, Peng; Zhou, Ding; Liu, Weiqing; Fang, Hai

    2017-08-01

    This work studies the time-dependent behavior of a layered arch adhesively bonded by viscoelastic interlayers. The deformation of the viscoelastic interlayer is represented by the Maxwell-Wiechert model. The constitutive relation in an interlayer is simplified through the quasi-elastic approximation approach. The mechanical property of an arch layer is described by the exact two-dimensional (2-D) elasticity theory in polar coordinates. The stress and displacement components in an arch layer, which strictly satisfy the simply supported boundary conditions, have been analytically derived out. The stresses and displacements are efficiently obtained by means of the recursive matrix method for the arch with any number of layers. The comparison study shows that the 2-D finite element solution has good agreement with the present one, while the solution based on the one-dimensional (1-D) Euler-Bernoulli theory has considerable error, especially for thick arches. The influences of geometrical and material parameters on the time-dependent behavior of the layered arch are analyzed in detail.

  14. Modified protrusion arch for anterior crossbite correction - a case report.

    PubMed

    Roy, Abhishek Singha; Singh, Gulshan Kr; Tandon, Pradeep; Chaudhary, Ramsukh

    2013-01-01

    Borderline and mild skeletal Class III relationships in adult patients are usually treated by orthodontic camouflage. Reasonably rood results have been achieved with nonsurgical teatment of anterior crossbite. Class III malocclusion may be associated with mandibular prognathism, maxillary retrognathism, or both. Class III maxillary retrognathism generally involves anterior crossbite, which must be opened if upper labial brackets are to be bonded. If multiple teeth are in crossbite, after opening the bite usual step is to ligate forward or advancement arch made of 0.018" or 0.020" stainless steel or NiTi wire main arch that must be kept separated 2 mm from the slot ofupper incisor braces. Two stops or omegas are made 1 mm mesial to the tubes of the molar bands that will impede main arch from slipping,and in this manner the arch will push the anterior teeth forward Here we have fabricated a modified multiple loop protrusion arch to correct an anterior crossbite with severe crowding that was not amenable to correct by advancement arches.

  15. Comparison of arch forms between Turkish and North American

    PubMed Central

    Celebi, Ahmet A.; Keklik, Hakan; Tan, Enes; Ucar, Faruk I.

    2016-01-01

    ABSTRACT Objective: The aim of this study was to clarify the morphological differences in the mandibular arches of Turkish and North American white subjects. Methods: The sample included 132 Turkish (34 Class I, 58 Class II, and 40 Class III) and 160 North American (60 Class I, 50 Class II, and 50 Class III) subjects. The most facial portion of 13 proximal contact areas was digitized from photocopied images of patients' mandibular dental arches. Clinical bracket points were calculated for each tooth based on mandibular tooth thickness data. Four linear and two proportional measurements were taken. The subjects were grouped according to arch form types (tapered, ovoid and square) in order to have frequency distribution compared between ethnic groups in each Angle classification. Results: The Turkish group showed significantly lower molar depth and more significant molar width-depth (W/D) ratio in all three Angle classifications. On the other hand, the Turkish group also showed a significantly larger intercanine width in Class III malocclusion and intermolar width in Class II malocclusion. The most frequent arch forms seen were the ovoid arch form in the Turkish group and the tapered form in the white group. Conclusions: Our results demonstrate that when treating Turkish patients, one should expect to use preformed ovoid arch form orthodontic wires in a significant percentage of patients. PMID:27275615

  16. Monitoring system of arch bridge for safety network management

    NASA Astrophysics Data System (ADS)

    Joo, Bong Chul; Yoo, Young Jun; Lee, Chin Hyung; Park, Ki Tae; Hwang, Yoon Koog

    2010-03-01

    Korea has constructed the safety management network monitoring test systems for the civil infrastructure since 2006 which includes airport structure, irrigation structure, railroad structure, road structure, and underground structure. Bridges among the road structure include the various superstructure types which are Steel box girder bridge, suspension bridge, PSC-box-girder bridge, and arch bridge. This paper shows the process of constructing the real-time monitoring system for the arch bridge and the measured result by the system. The arch type among various superstructure types has not only the structural efficiency but the visual beauty, because the arch type superstructure makes full use of the feature of curve. The main measuring points of arch bridges composited by curved members make a difference to compare with the system of girder bridges composited by straight members. This paper also shows the method to construct the monitoring system that considers the characteristic of the arch bridge. The system now includes strain gauges and thermometers, and it will include various sensor types such as CCTV, accelerometers and so on additionally. For the long term and accuracy monitoring, the latest optical sensors and equipments are applied to the system.

  17. Translocation of the Aortic Arch with Norwood Procedure for Hypoplastic Left Heart Syndrome Variant with Circumflex Retroesophageal Aortic Arch

    PubMed Central

    Lee, Chee-Hoon; Seo, Dong Ju; Bang, Ji Hyun; Goo, Hyun Woo; Park, Jeong-Jun

    2014-01-01

    Retroesophageal aortic arch, in which the aortic arch crosses the midline behind the esophagus to the contralateral side, is a rare form of vascular anomaly. The complete form may cause symptoms by compressing the esophagus or the trachea and need a surgical intervention. We report a rare case of a hypoplastic left heart syndrome variant with the left retroesophageal circumflex aortic arch in which the left aortic arch, retroesophageal circumflex aorta, and the right descending aorta with the aberrant right subclavian artery encircle the esophagus completely, thus causing central bronchial compression. Bilateral pulmonary artery banding and subsequent modified Norwood procedure with extensive mobilization and creation of the neo-aorta were performed. As a result of the successful translocation of the aorta, the airway compression was relieved. The patient underwent the second-stage operation and is doing well currently. PMID:25207249

  18. Prenatal diagnosis of a rare aortic arch anomaly with left aortic arch and right ductus arteriosus: Cross ribbon sign

    PubMed Central

    Vijayaraghavan, S Boopathy; Senthil, Sathiya; Latha, K

    2017-01-01

    Here, we report a fetus with a rare aortic arch anomaly with left aortic arch and right ductus arteriosus, which has not been reported so far. In this condition, the aorta extends to the left of the trachea as in normal, while the ductus arteriosus extends to the right of the trachea and joins the descending aorta posterior to the trachea, with a cross-ribbon sign. PMID:28515590

  19. Immunity by equilibrium.

    PubMed

    Eberl, Gérard

    2016-08-01

    The classical model of immunity posits that the immune system reacts to pathogens and injury and restores homeostasis. Indeed, a century of research has uncovered the means and mechanisms by which the immune system recognizes danger and regulates its own activity. However, this classical model does not fully explain complex phenomena, such as tolerance, allergy, the increased prevalence of inflammatory pathologies in industrialized nations and immunity to multiple infections. In this Essay, I propose a model of immunity that is based on equilibrium, in which the healthy immune system is always active and in a state of dynamic equilibrium between antagonistic types of response. This equilibrium is regulated both by the internal milieu and by the microbial environment. As a result, alteration of the internal milieu or microbial environment leads to immune disequilibrium, which determines tolerance, protective immunity and inflammatory pathology.

  20. Generation of electromagnetic emission during the injection of dense supersonic plasma flows into arched magnetic field

    NASA Astrophysics Data System (ADS)

    Viktorov, Mikhail; Golubev, Sergey; Mansfeld, Dmitry; Vodopyanov, Alexander

    2016-04-01

    Interaction of dense supersonic plasma flows with an inhomogeneous arched magnetic field is one of the key problems in near-Earth and space plasma physics. It can influence on the energetic electron population formation in magnetosphere of the Earth, movement of plasma flows in magnetospheres of planets, energy release during magnetic reconnection, generation of electromagnetic radiation and particle precipitation during solar flares eruption. Laboratory study of this interaction is of big interest to determine the physical mechanisms of processes in space plasmas and their detailed investigation under reproducible conditions. In this work a new experimental approach is suggested to study interaction of supersonic (ion Mach number up to 2.7) dense (up to 1015 cm-3) plasma flows with inhomogeneous magnetic field (an arched magnetic trap with a field strength up to 3.3 T) which opens wide opportunities to model space plasma processes in laboratory conditions. Fully ionized plasma flows with density from 1013 cm-3 to 1015 cm-3 are created by plasma generator on the basis of pulsed vacuum arc discharge. Then plasma is injected in an arched open magnetic trap along or across magnetic field lines. The filling of the arched magnetic trap with dense plasma and further magnetic field lines break by dense plasma flow were experimentally demonstrated. The process of plasma deceleration during the injection of plasma flow across the magnetic field lines was experimentally demonstrated. Pulsed plasma microwave emission at the electron cyclotron frequency range was observed. It was shown that frequency spectrum of plasma emission is determined by position of deceleration region in the magnetic field of the magnetic arc, and is affected by plasma density. Frequency spectrum shifts to higher frequencies with increasing of arc current (plasma density) because the deceleration region of plasma flow moves into higher magnetic field. The observed emission can be related to the

  1. Determination of nonaxisymmetric equilibrium

    SciTech Connect

    Elkin, D.

    1980-01-01

    The Princeton Equilibrium Code is modified to determine the equilibrium surfaces for a large aspect ratio toroidal system with helical magnetic fields. The code may easily be made to include any variety of modes. Verification of the code is made by comparison with an analytic solution for l = 3. Previously observed shifting of the magnetic axis with increasing pressure or with a changed externally applied vertical field is obtained. The case l = 0, a bumpy torus, gives convergence only for the lenient convergence tolerance of epsilon/sub b/ = 1.0 x 10-/sup 2/.

  2. Beyond Equilibrium Thermodynamics

    NASA Astrophysics Data System (ADS)

    Öttinger, Hans Christian

    2005-01-01

    Beyond Equilibrium Thermodynamics fills a niche in the market by providing a comprehensive introduction to a new, emerging topic in the field. The importance of non-equilibrium thermodynamics is addressed in order to fully understand how a system works, whether it is in a biological system like the brain or a system that develops plastic. In order to fully grasp the subject, the book clearly explains the physical concepts and mathematics involved, as well as presenting problems and solutions; over 200 exercises and answers are included. Engineers, scientists, and applied mathematicians can all use the book to address their problems in modelling, calculating, and understanding dynamic responses of materials.

  3. Relationship Between Ambulatory Blood Pressure and Aortic Arch Atherosclerosis

    PubMed Central

    Iwata, Shinichi; Jin, Zhezhen; Schwartz, Joseph E; Homma, Shunichi; Elkind, Mitchell S.V.; Rundek, Tatjana; Sacco, Ralph L.; Di Tullio, Marco R.

    2012-01-01

    Objective Atherosclerotic plaque in the aortic arch is an independent risk factor for ischemic stroke. Although high blood pressure (BP) measured at the doctor’s office is known to be associated with aortic atherosclerosis, little is known on the association between 24-hour ambulatory BP and aortic arch plaque presence and severity. Our objective was to clarify the association between ambulatory BP variables and aortic arch atherosclerosis in a community-based cohort. Methods The study population consisted of 795 patients (mean age 71±9 years) participating in the Cardiovascular Abnormalities and Brain Lesions (CABL) study who underwent 24-hour ambulatory BP monitoring (ABPM). Arch plaque was evaluated by 2D transthoracic echocardiography from a suprasternal window. Results All systolic ABPM variables (24-hour/daytime/nighttime mean systolic BP, daytime/nighttime systolic BP variability) were associated with the presence of any plaque and large (≥4mm) plaque, whereas diastolic BP variables were not associated with aortic atherosclerosis. Multiple regression analysis indicated that nighttime systolic BP variability (expressed as the standard deviation of nighttime systolic BP) remained independently associated with large plaque after adjustment for age, sex, cigarette smoking, history of hypertension, diabetes mellitus, hypercholesterolemia, anti-hypertensive medication and nighttime mean systolic BP (odds ratio 1.39 per 1 standard deviation increase, 95% CI 1.00 to 1.93, P<0.05). Conclusion Systolic ABPM variables are significantly associated with the presence of arch plaque. Nighttime systolic BP variability is independently associated with large arch plaque. These findings may have important implications in gaining further insights into the mechanism of arch plaque formation and progression. PMID:22296886

  4. Relationship between ambulatory blood pressure and aortic arch atherosclerosis.

    PubMed

    Iwata, Shinichi; Jin, Zhezhen; Schwartz, Joseph E; Homma, Shunichi; Elkind, Mitchell S V; Rundek, Tatjana; Sacco, Ralph L; Di Tullio, Marco R

    2012-04-01

    Atherosclerotic plaque in the aortic arch is an independent risk factor for ischemic stroke. Although high blood pressure (BP) measured at the doctor's office is known to be associated with aortic atherosclerosis, little is known on the association between 24-h ambulatory BP and aortic arch plaque presence and severity. Our objective was to clarify the association between ambulatory BP variables and aortic arch atherosclerosis in a community-based cohort. The study population consisted of 795 patients (mean age 71 ± 9 years) participating in the Cardiovascular Abnormalities and Brain Lesions (CABL) study who underwent 24-h ambulatory BP monitoring (ABPM). Arch plaque was evaluated by 2D transthoracic echocardiography from a suprasternal window. All systolic ABPM variables (24-h/daytime/nighttime mean systolic BP, daytime/nighttime systolic BP variability) were associated with the presence of any plaque and large (≥ 4 mm) plaque, whereas diastolic BP variables were not associated with aortic atherosclerosis. Multiple regression analysis indicated that nighttime systolic BP variability (expressed as the standard deviation of nighttime systolic BP) remained independently associated with large plaque after adjustment for age, sex, cigarette smoking, history of hypertension, diabetes mellitus, hypercholesterolemia, anti-hypertensive medication and nighttime mean systolic BP (odds ratio 1.39 per 1 standard deviation increase, 95% CI 1.00-1.93, P<0.05). Systolic ABPM variables are significantly associated with the presence of arch plaque. Nighttime systolic BP variability is independently associated with large arch plaque. These findings may have important implications in gaining further insights into the mechanism of arch plaque formation and progression. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  5. Elastic responses of underground circular arches considering dynamic soil-structure interaction: A theoretical analysis

    NASA Astrophysics Data System (ADS)

    Chen, Hai-Long; Jin, Feng-Nian; Fan, Hua-Lin

    2013-02-01

    Due to the wide applications of arches in underground protective structures, dynamic analysis of circular arches including soil-structure interactions is important. In this paper, an exact solution of the forced vibration of circular arches subjected to subsurface denotation forces is obtained. The dynamic soil-structure interaction is considered with the introduction of an interfacial damping between the structure element and the surrounding soil into the equation of motion. By neglecting the influences of shear, rotary inertia and tangential forces and assuming the arch incompressible, the equations of motion of the buried arches were set up. Analytical solutions of the dynamic responses of the protective arches were deduced by means of modal superposition. Arches with different opening angles, acoustic impedances and rise-span ratios were analyzed to discuss their influences on an arch. The theoretical analysis suggests blast loads for elastic designs and predicts the potential failure modes for buried protective arches.

  6. An Updated Equilibrium Machine

    ERIC Educational Resources Information Center

    Schultz, Emeric

    2008-01-01

    A device that can demonstrate equilibrium, kinetic, and thermodynamic concepts is described. The device consists of a leaf blower attached to a plastic container divided into two chambers by a barrier of variable size and form. Styrofoam balls can be exchanged across the barrier when the leaf blower is turned on and various air pressures are…

  7. An Updated Equilibrium Machine

    ERIC Educational Resources Information Center

    Schultz, Emeric

    2008-01-01

    A device that can demonstrate equilibrium, kinetic, and thermodynamic concepts is described. The device consists of a leaf blower attached to a plastic container divided into two chambers by a barrier of variable size and form. Styrofoam balls can be exchanged across the barrier when the leaf blower is turned on and various air pressures are…

  8. [Relationship between aortic arch shape and blood pressure response after coarctation repair].

    PubMed

    Ou, P; Mousseaux, E; Auriacombe, L; Pédroni, E; Balleux, F; Sidi, D; Bonnet, D

    2005-01-01

    The mechanisms of secondary hypertension after repair of coarctation of the aorta are not well understood. Abnormalities of the architecture of the aortic arch and their consequences on blood pressure have not been studied. In order to study the relationship between abnormalities or aortic arch architecture and resting blood pressure ninety-four patients without re-coarctation were followed up prospectively from 1997 to 2004 (mean age 16.9 +/- 8.1 years; mean weight 57.5 +/- 18.3 Kg; interval since surgery 16.3 +/- 5.4 years). All underwent MRI angiography of the thoracic aorta which enabled the abnormalities to be classified in 3 groups: gothic arch, crenellated arch and roman arch. Twenty-four patients (25.5%) were hypertensive and 70 (74.4%) normotensive. There were 40 gothic arches (42.5%). 14 crenellated arches (15%) and 40 roman arches (42.5%). Gothic arches were more commonly observed in the hypertensive patients (18/40, [45%, 95% CI 31-62]) than the crenellated arches (4/14, [28.5%, 95% CI 7-48]) or the roman arches (2/40, [5%, 95% CI 2-12]). Only the gothic arch was independently correlated with hypertension on multivariate analysis. The authors conclude that gothic deformation of the aortic arch is an independent predictive factor of hypertension in patients operated for coarctation with an excellent result on the isthmic region. Patients with a gothic appearance of their aortic arch should be followed up closely.

  9. An Infrared Study of the Dust Properties and Geometry of the Arched Filaments H ii Region with SOFIA/FORCAST

    NASA Astrophysics Data System (ADS)

    Hankins, M. J.; Lau, R. M.; Morris, M. R.; Herter, T. L.

    2017-03-01

    Massive stellar clusters provide radiation (˜ {10}7{--}{10}8 {L}⊙ ) and winds (˜1000 km s-1) that act to heat dust and shape their surrounding environment. In this paper, the Arched Filaments in the Galactic center were studied to better understand the influence of the Arches cluster on its nearby interstellar medium (ISM). The Arched Filaments were observed with the Faint Object InfraRed CAMera for the SOFIA Telescope at 19.7, 25.2, 31.5, and 37.1 μm. Color-temperature maps of the region created with the 25.2 and 37.1 μm data reveal relatively uniform dust temperatures (70-100 K) over the extent of the filaments (˜25 pc). Distances between the cluster and the filaments were calculated assuming equilibrium heating of standard-size ISM dust grains (˜0.1 μm). The distances inferred by this method are in conflict with the projected distance between the filaments and the cluster, although this inconsistency can be explained if the characteristic grain size in the filaments is smaller (˜0.01 μm) than typical values. DustEM models of selected locations within the filaments show evidence of depleted abundances of polycyclic aromatic hydrocarbons (PAHs) by factors of ˜1.6-10 by mass compared to the diffuse ISM. The evidence for both PAH depletion and a smaller characteristic grain size points to processing of the ISM within the filaments. We argue that the eroding of dust grains within the filaments is not likely attributable to the radiation or winds from the Arches cluster, but may be related to the physical conditions in the Galactic center.

  10. Role of Hox PG2 genes in Nile tilapia pharyngeal arch specification: implications for gnathostome pharyngeal arch evolution.

    PubMed

    Le Pabic, Pierre; Scemama, Jean-Luc; Stellwag, Edmund J

    2010-01-01

    Phylogenetic reconstructions suggest that the ancestral osteichthyan Hox paralog group 2 gene complement was composed of two genes, Hoxa2 and b2, both of which have been retained in tetrapods, but only one of which functions as a selector gene of second pharyngeal arch identity (PA2). Genome duplication at the inception of the teleosts likely generated four Hox PG2 genes, only two of which, hoxa2b and b2a, have been preserved in zebrafish, where they serve as functionally redundant PA2 selector genes. Evidence from our laboratory has shown that other telelosts, specifically striped bass and Nile tilapia, harbor three transcribed Hox PG2 genes, hoxa2a, a2b, and b2a, with unspecified function(s). We have focused on characterizing the function of the three Nile tilapia Hox PG2 genes as a model to examine the effects of postgenome duplication gene loss on the evolution of developmental gene function. We studied Hox PG2 gene function in tilapia by examining the effects of independent morpholino oligonucleotide (MO)-induced knockdowns on pharyngeal arch morphology and Hox gene expression patterns. Morphological defects resulting from independent MO-induced knockdowns of tilapia hoxa2a, a2b, and b2a included the expected PA2 to PA1 homeotic transformations previously observed in tetrapods and zebrafish, as well as concordant and unexpected morphological changes in posterior arch-derived cartilages. Of particular interest, was the observation of a MO-induced supernumerary arch between PA6 and PA7, which occurred concomitantly with other MO-induced pharyngeal arch defects. Beyond these previously unreported morphant-induced transformations, a comparison of Hox PG2 gene expression patterns in tilapia Hox PG2 morphants were indicative of arch-specific auto- and cross-regulatory activities as well as a Hox paralog group 2 interdependent regulatory network for control of pharyngeal arch specification.

  11. A Palaeozoic shark with osteichthyan-like branchial arches.

    PubMed

    Pradel, Alan; Maisey, John G; Tafforeau, Paul; Mapes, Royal H; Mallatt, Jon

    2014-05-29

    The evolution of serially arranged, jointed endoskeletal supports internal to the gills--the visceral branchial arches--represents one of the key events in early jawed vertebrate (gnathostome) history, because it provided the morphological basis for the subsequent evolution of jaws. However, until now little was known about visceral arches in early gnathostomes, and theories about gill arch evolution were driven by information gleaned mostly from both modern cartilaginous (chondrichthyan) and bony (osteichthyan) fishes. New fossil discoveries can profoundly affect our understanding of evolutionary history, by revealing hitherto unseen combinations of primitive and derived characters. Here we describe a 325 million year (Myr)-old Palaeozoic shark-like fossil that represents, to our knowledge, the earliest identified chondrichthyan in which the complete gill skeleton is three-dimensionally preserved in its natural position. Its visceral arch arrangement is remarkably osteichthyan-like, suggesting that this may represent the common ancestral condition for crown gnathostomes. Our findings thus reinterpret the polarity of some arch features of the crown jawed vertebrates and invert the classic hypothesis, in which modern sharks retain the ancestral condition. This study underscores the importance of early chondrichthyans in resolving the evolutionary history of jawed vertebrates.

  12. Dynamics of breaking arches under a constant vibration

    NASA Astrophysics Data System (ADS)

    Guerrero, Bruno; Lozano, Celia; Zuriguel, Iker; Garcimartín, Angel

    2017-06-01

    Granular flow through an orifice can be suddenly halted by the formation of arches in the vicinity of the outlet, which are stable under the action of gravity. They may be broken when an external driving (for instance, vibration) is applied. With the aim of shedding light on the dynamics of arch destruction, we built an experiment consisting of a vertical two-dimensional silo filled with monodisperse beads, to which a constant vibration is applied. It was previously found that an important parameter to predict the robustness of the arch is the angle between consecutive beads. We focus on long-enduring arches and study the angles among the beads along time. We have found that in many cases the dynamics of the largest angle determines the breaking of the arch; it does not only determine where the "weakest link" is, but also the process that leads to the final destabilization. This is interesting because it can provide information about whether the flow will resume in a well-defined time or not, which is especially useful for industrial processes that have to constantly deal with the possible emergence of clogs.

  13. Dental arch dimensional changes after adenotonsillectomy in prepubertal children.

    PubMed

    Petraccone Caixeta, Anna Cristina; Andrade, Ildeu; Bahia Junqueira Pereira, Tatiana; Franco, Letícia Paiva; Becker, Helena Maria Gonçalves; Souki, Bernardo Quiroga

    2014-04-01

    The purposes of this study were to investigate the dental arch changes after adenotonsillectomies in prepubertal children and to compare the dental arch dimensions of mouth-breathing and nasal-breathing children. The sample included 49 prepubertal severely obstructed mouth-breathing children and 46 prepubertal nasal-breathing children. Twenty-four of the 49 mouth-breathing children had an adenotonsillectomy and composed the adenotonsillectomy subgroup. The 25 children in whom the mouth-breathing pattern was unchanged during the 1-year study period composed the control subgroup. The mouth-breathing children showed a deeper palatal vault, a larger mandibular width, and a larger mandibular arch length in comparison with the nasal-breathing children. After airway clearance, the adenotonsillectomy group showed a significant maxillary transverse width gain compared with the control subgroup. The control subgroup showed a significant deepening of the palatal height when compared with the adenotonsillectomy subgroup after 1 year. The adenotonsillectomy subgroup had a significantly different pattern of arch development compared with the untreated controls. After adenotonsillectomy, the mouth-breathing children showed greater maxillary transverse development than did the controls. The palatal vault deepened in the untreated children. The mouth-breathing children showed a deeper palatal vault, a larger mandibular width, and a larger mandibular arch length in comparison with the nasal-breathing children. Copyright © 2014 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  14. Characterization of the cephalic arch and location of stenosis

    PubMed Central

    Bennett, Shelby; Hammes, Mary S.; Blicharski, Tom; Watson, Sydeaka; Funaki, Brian

    2015-01-01

    Purpose The purpose of this study is to accurately characterize the cephalic arch segments into four domains and to enable more specific evaluation of cephalic arch stenosis (CAS) and determine the frequency of stenosis in each domain. Methods After Institutional Review Board (IRB) approval, a retrospective chart review was done to define a population of patients receiving hemodialysis who developed CAS as apparent on clinically indicated radiologic imaging. A standardized approach was devised to categorize four domains of the cephalic arch. Domain I was defined as the peripheral portion of the arch and Domain IV was the distal portion of the cephalic vein near termination with the axillary vein. The magnitude of stenosis as measured by percentage was determined and compared in the four domains. Results The most frequent location for stenosis was found in domain IV when compared with domains II or I (p<0.01). The magnitude of stenosis differed across all domains (p<0.001) with the least common place for CAS in domain I. Treatment of CAS included angioplasty in all, thrombectomy in eight, and stent placement in five. Conclusions CAS occurs most commonly in the terminal portion of the arch. Four standardized domains have been defined; future work will validate these findings and determine the best intervention for each domain. PMID:25198819

  15. Immediate implants in anterior maxillary arch

    PubMed Central

    Anitha, K.; Kumar, S. Senthil; Babu, M. R. Ramesh; Candamourty, Ramesh; Thirumurugan

    2014-01-01

    Aim: The aim of the study was to evaluate the osseo-integration and soft tissue status of the endosseous implants placed in immediate extraction socket. Methodology: Seven patients (4 males and 3 females) aged 20-30 years were selected for the study. Nine implants were placed in seven patients in the maxillary arch. All the patients were clinically αnd thoroughly examined. Under local anesthesia, the indicated tooth was extracted. The extracted socket was prepared using standard drills with palatal wall as guide. The longest and widest implants were placed (Hi-Tec Implants). All implants showed good primary stability. The implants used in the study were tapered design endosseous implants with Threaded implants (TI) unit plasma-sprayed surface. Surgical re-entry (secondary surgery) was performed to remove the healing cap after 6 months for supra crestal fabrication. All patients were reviewed periodically at 3rd and 6th month interval and the following clinical parameters including modified plaque index (mPlI), modified bleeding index (mBI), probing depth (PD), attachment level (AL), and distance between the implant shoulder and mucosal margin (DIM), distance between the implant shoulder and first bone-implant contact, and Clinical Mobility Index were recorded. The results were computed and subjected to statistical evaluation. Results: The mPlI, mBI, PD, AL, and DIM were evaluated around the implants at baseline, 3rd and 6th month intervals and analyzed statistically by Friedman T-test. The results of the above were shown to be statistically non-significant. The distance between the implant shoulder and first bone implant contact was evaluated around the implants at base line, 3rd and 6th month intervals. The results proved to be statistically significant (0.01) implying that there was a bone apposition around the implants. Conclusion: During the course of the study, soft tissue status around implants was found to be healthy. Osseointegration as assessed by

  16. Non-Equilibrium Molecular Dynamics

    NASA Astrophysics Data System (ADS)

    Ciccotti, Giovanni; Kapral, Raymond; Sergi, Alessandro

    Statistical mechanics provides a well-established link between microscopic equilibrium states and thermodynamics. If one considers systems out of equilibrium, the link between microscopic dynamical properties and non-equilibrium macroscopic states is more difficult to establish [1,2]. For systems lying near equilibrium, linear response theory provides a route to derive linear macroscopic laws and the microscopic expressions for the transport properties that enter the constitutive relations. If the system is displaced far from equilibrium, no fully general theory exists to treat such systems. By restricting consideration to a class of non-equilibrium states which arise from perturbations (linear or non-linear) of an equilibrium state, methods can be developed to treat non-equilibrium states. Furthermore, non-equilibrium molecular dynamics (NEMD) simulation methods can be devised to provide estimates for the transport properties of these systems.

  17. Aortic arch aneurysm: short- and mid-term results comparing open arch surgery and the hybrid procedure†.

    PubMed

    Cazavet, Alexandre; Alacoque, Xavier; Marcheix, Bertrand; Chaufour, Xavier; Rousseau, Herve; Glock, Yves; Leobon, Bertrand

    2016-01-01

    Open arch surgery for aortic arch aneurysm was historically associated with a high risk of postoperative morbi-mortality. Improved operative techniques have now lowered the incidence of these complications but in parallel, hybrid arch procedures have emerged. Nowadays, very little data are available about their mid-term results compared with open surgery. From January 2002 to January 2014, 46 patients had treatment for an exclusive aortic arch aneurysm including 25 open arch surgeries and 21 type I hybrid arch procedures in our institution. All cases involved arch aneurysms involving at least one carotid artery (Zone 0 and Zone 1). Aneurysms of the distal arch and descending aorta were excluded (Zone 2 and beyond). Results from a retrospective database are reported. There were no patients lost to the follow-up. There was no significant difference in preoperative comorbidities between the two groups. The incidence of in-hospital mortality was similar at 20% (5/25) for open surgery and 19% (4/21) for hybrid procedure (P = 0.830). The incidence of permanent cerebral neurological deficit was comparable at 17.4% (4/23) for open surgery and 21.1% (4/19) for hybrid procedure (P = 1). Median survival was 109.5 months for open surgery and 56.3 months for hybrid procedure. Freedom from all-cause mortality was 78, 63, 63 and 57% at 1, 3, 5 and 7 years, respectively in the open surgical group. Freedom from all-cause mortality was 74, 55, 46 and 28% at 1, 3, 5 and 7 years, respectively in the hybrid group. Survival rates and incidence of major adverse cardiac and cerebro-vascular event between open surgery and hybrid procedure were not statistically different (P = 0.530 and P = 0.325, respectively). However, incidence of reintervention was in favour of open surgery [14.5 vs 44.8% at 7 years, P = 0.045; 95% confidence interval: (0.06-0.97)]. The type I hybrid arch procedure fails to demonstrate better results compared with open surgery, regarding morbi-mortality at the short

  18. Morphology of aortic arch obstruction with patent ductus arteriosus

    PubMed Central

    Marino, Bruno; Chiariello, Luigi; Mercanti, Corrado; Bosman, Cesare; Colloridi, Vicenzo; Reale, Attilio; Marino, Benedetto

    1981-01-01

    Thirty-one hearts with aortic arch obstruction and patent ductus arteriosus were examined with special reference to associated cardiac anomalies. Six presented with complete interruption of the aortic arch, four with atretic isthmus, twelve with coarctation, and three with tubular hypoplasia. Associated cardiac anomalies were divided into two main groups: (1) septal defect with left-to-right shunt, and (2) left ventricular inflow and/or outflow obstruction. A high incidence (9/19=47.4%) of ventriculo-infundibular malalignment type of ventricular septal defect with subaortic stenosis was observed. Associated cardiac lesions that reduce blood flow in the aortic arch during fetal life may be responsible for poor development of this structure. Images PMID:15216214

  19. Numerical Modelling of Soil Arching in a Shallow Backfill Layer

    NASA Astrophysics Data System (ADS)

    Szajna, Waldemar St.

    2015-03-01

    The paper presents the application of the finite element method into the modelling of soil arching. The phenomenon plays fundamental role in soil-shell flexible structures behaviour. To evaluate the influence of arching on a pressure reduction, a plain strain trapdoor under a shallow layer of backfill was simulated. The Coulomb-Mohr plasticity condition and the nonassociated flow rule were used for the soil model. The research examines the impact of the internal friction angle and the influence of the backfill layer thickness on the value of soil arching. The carried out analyses indicate that the reduction of pressures acting on a structure depends on the value of the internal friction angle, which confirms the earlier research. For a shallow backfill layer however, the reduction is only a local phenomenon and can influence only a part of the structure.

  20. Buckling of Low Arches or Curved Beams of Small Curvature

    NASA Technical Reports Server (NTRS)

    Fung, Y C; Kaplan, A

    1952-01-01

    A general solution, based on the classical buckling criterion, is given for the problem of buckling of low arches under a lateral loading acting toward the center of curvature. For a sinusoidal arch under sinusoidal loading, the critical load can be expressed exactly as a simple function of the beam dimension parameters. For other arch shapes and load distributions, approximate values of the critical load can be obtained by summing a few terms of a rapidly converging Fourier series. The effects of initial end thrust and axial and lateral elastic support are discussed. The buckling load based on energy criterion of Karman and Tsien is also calculated. Results for both the classical and the energy criteria are compared with experimental results.

  1. Simulation of Laboratory Tests of Steel Arch Support

    NASA Astrophysics Data System (ADS)

    Horyl, Petr; Šňupárek, Richard; Maršálek, Pavel; Pacześniowski, Krzysztof

    2017-03-01

    The total load-bearing capacity of steel arch yielding roadways supports is among their most important characteristics. These values can be obtained in two ways: experimental measurements in a specialized laboratory or computer modelling by FEM. Experimental measurements are significantly more expensive and more time-consuming. However, for proper tuning, a computer model is very valuable and can provide the necessary verification by experiment. In the cooperating workplaces of GIG Katowice, VSB-Technical University of Ostrava and the Institute of Geonics ASCR this verification was successful. The present article discusses the conditions and results of this verification for static problems. The output is a tuned computer model, which may be used for other calculations to obtain the load-bearing capacity of other types of steel arch supports. Changes in other parameters such as the material properties of steel, size torques, friction coefficient values etc. can be determined relatively quickly by changing the properties of the investigated steel arch supports.

  2. Evaluation of dental arch width and form changes after orthodontic treatment and retention with a new computerized method.

    PubMed

    Taner, Tülin Ugur; Ciger, Semra; El, Hakan; Germeç, Derya; Es, Alphan

    2004-10-01

    The purpose of this study was to evaluate longitudinal arch width and form changes and to define arch form types with a new computerized method. Maxillary and mandibular models of 21 Class II Division 1 patients were examined before treatment (T(0)), after treatment (T(1)), and an average of 3 years after retention (T(2)). Arch width measurements were made directly on scanned images of maxillary and mandibular models. Arch form changes at T(0)-T(1) and T(1)-T(2) were evaluated by superimposing the computer-generated Bezier arch curves with a computer program. Types of dental arch forms were defined by superimposing them with the pentamorphic arch system, which included 5 different types of arch forms: normal, ovoid, tapered, narrow ovoid, and narrow tapered. Maxillary arch widths were increased during orthodontic treatment. Mandibular posterior arch widths were also increased. The expansion of the mandibular arch forms was less than in the maxillary arch forms. Arch width changes were generally stable, except for reduction in maxillary and mandibular interlateral, inter-first premolar, and mandibular intercanine widths. Pretreatment maxillary arch forms were mostly tapered; mandibular arch forms were tapered and narrow tapered. In maxillary arch forms, 76% of the treatment changes were maintained. Mandibular arch form was maintained in 67% of the sample, both during treatment and after retention. In mandibular arches, 71% of orthodontically induced arch form changes were maintained.

  3. Zygomatic Arch Cortical Area and Diet in Haplorhines.

    PubMed

    Edmonds, Hallie

    2016-12-01

    The influence that various types of ingested foods have on the form (size and shape) of specific features of the masticatory system is an area in which many questions remain unanswered. The bony zygomatic arch, the focus of this study, is directly linked to the masticatory system because it serves as the anchor for the masseter muscle, a primary muscle of chewing and source of masticatory force. However, the influence of diet and the forces associated with different diet types on the arch's internal bone architecture is not well understood. Despite the breadth of work centered around the craniofacial complex and biomechanics of mastication, there is a need for further investigations into the functional relationships between specific bony features that experience high strains, (e.g., the zygomatic arch), and the masticatory forces generated by different diets (e.g., mechanically resistant versus non- mechanically resistant) across non-human primates. A hypothesis and series of predictions assessing diet in relation to variability in cortical area distributions and values of section moduli (measures of bone strength) throughout the zygomatic arch were tested in a sample of haplorhine primates. Cortical area and measures of section moduli appear to track with the known masticatory strain distribution along the zygomatic arch. Pairwise comparisons between closely related taxa of different diets reveal significant differences in anterior cortical area and section moduli values. These results imply that differences in masticatory loading due to diet manifest in the zygomatic arch's internal bone structure. Anat Rec, 299:1789-1800, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  4. Photoelastic analysis of stress generated by Connecticut Intrusion Arch (CIA).

    PubMed

    Schwertner, Alessandro; Almeida, Renato Rodrigues de; Gonini, Alcides; Almeida, Marcio Rodrigues de

    2017-02-01

    The present in vitro study evaluated, by means of the photoelastic technique, the effects generated by the Connecticut Intrusion Arch (CIA), with a 90o bend on the distal surface of molar tubes and using the 4 x 2 appliance on the anterior and posterior regions of the upper dental arch. Five models were manufactured, in which two different clinical situations were correlated: 1) use of intrusion arch not cinched back and transpalatal bar for anchorage (Group 1); 2) use of intrusion arch cinched back and transpalatal bar for anchorage (Group 2). Stress generated in the apical and middle regions of tooth roots of maxillary anterior teeth and maxillary first molars was evaluated. Taking a reference value of 1.0 MPa = 100%, qualitative descriptive analysis was performed, which showed uniformity between stress values in the apical region of anterior teeth of both groups (G1 and G2). In the posterior region, for models with the arch cinched back (G2), stress remained within 100%. As for G1 models (with the arch not cinched back), variations in the mesial surface of first molars were observed, with an increase of 20% in the generated stress. The apical region did not undergo any changes, while in the distal region of molars there was a decrease of 20% in stress. Laboratory results revealed differences in stress between Groups 1 and 2 in the molar region, thereby indicating that there was a tendency towards mesial root tipping of first molars when the distal end of the CIA was not cinched back.

  5. Aortic arch compliance and idiopathic unilateral vocal fold paralysis.

    PubMed

    Behkam, Reza; Roberts, Kara E; Bierhals, Andrew J; Jacobs, M Eileen; Edgar, Julia D; Paniello, Randal C; Woodson, Gayle; Vande Geest, Jonathan P; Barkmeier-Kraemer, Julie M

    2017-08-01

    Unilateral vocal fold paralysis (UVP) occurs related to recurrent laryngeal nerve (RLN) impairment associated with impaired swallowing, voice production, and breathing functions. The majority of UVP cases occur subsequent to surgical intervention with approximately 12-42% having no known cause for the disease (i.e., idiopathic). Approximately two-thirds of those with UVP exhibit left-sided injury with the average onset at ≥50 yr of age in those diagnosed as idiopathic. Given the association between the RLN and the subclavian and aortic arch vessels, we hypothesized that changes in vascular tissues would result in increased aortic compliance in patients with idiopathic left-sided UVP compared with those without UVP. Gated MRI data enabled aortic arch diameter measures normalized to blood pressure across the cardiac cycles to derive aortic arch compliance. Compliance was compared between individuals with left-sided idiopathic UVP and age- and sex-matched normal controls. Three-way factorial ANOVA test showed that aortic arch compliance (P = 0.02) and aortic arch diameter change in one cardiac cycle (P = 0.04) are significantly higher in patients with idiopathic left-sided UVP compared with the controls. As previously demonstrated by other literature, our finding confirmed that compliance decreases with age (P < 0.0001) in both healthy individuals and patients with idiopathic UVP. Future studies will investigate parameters of aortic compliance change as a potential contributor to the onset of left-sided UVP.NEW & NOTEWORTHY Unilateral vocal fold paralysis results from impaired function of the recurrent laryngeal nerve (RLN) impacting breathing, swallowing, and voice production. A large proportion of adults suffering from this disorder have an idiopathic etiology (i.e., unknown cause). The current study determined that individuals diagnosed with left-sided idiopathic vocal fold paralysis exhibited significantly greater compliance than age- and sex-matched controls

  6. Photoelastic analysis of stress generated by Connecticut Intrusion Arch (CIA)

    PubMed Central

    Schwertner, Alessandro; de Almeida, Renato Rodrigues; Gonini, Alcides; de Almeida, Marcio Rodrigues

    2017-01-01

    ABSTRACT Objective: The present in vitro study evaluated, by means of the photoelastic technique, the effects generated by the Connecticut Intrusion Arch (CIA), with a 90o bend on the distal surface of molar tubes and using the 4 x 2 appliance on the anterior and posterior regions of the upper dental arch. Methods: Five models were manufactured, in which two different clinical situations were correlated: 1) use of intrusion arch not cinched back and transpalatal bar for anchorage (Group 1); 2) use of intrusion arch cinched back and transpalatal bar for anchorage (Group 2). Stress generated in the apical and middle regions of tooth roots of maxillary anterior teeth and maxillary first molars was evaluated. Results: Taking a reference value of 1.0 MPa = 100%, qualitative descriptive analysis was performed, which showed uniformity between stress values in the apical region of anterior teeth of both groups (G1 and G2). In the posterior region, for models with the arch cinched back (G2), stress remained within 100%. As for G1 models (with the arch not cinched back), variations in the mesial surface of first molars were observed, with an increase of 20% in the generated stress. The apical region did not undergo any changes, while in the distal region of molars there was a decrease of 20% in stress. Conclusion: Laboratory results revealed differences in stress between Groups 1 and 2 in the molar region, thereby indicating that there was a tendency towards mesial root tipping of first molars when the distal end of the CIA was not cinched back. PMID:28444014

  7. Absolute Equilibrium Entropy

    NASA Technical Reports Server (NTRS)

    Shebalin, John V.

    1997-01-01

    The entropy associated with absolute equilibrium ensemble theories of ideal, homogeneous, fluid and magneto-fluid turbulence is discussed and the three-dimensional fluid case is examined in detail. A sigma-function is defined, whose minimum value with respect to global parameters is the entropy. A comparison is made between the use of global functions sigma and phase functions H (associated with the development of various H-theorems of ideal turbulence). It is shown that the two approaches are complimentary though conceptually different: H-theorems show that an isolated system tends to equilibrium while sigma-functions allow the demonstration that entropy never decreases when two previously isolated systems are combined. This provides a more complete picture of entropy in the statistical mechanics of ideal fluids.

  8. An Updated Equilibrium Machine

    NASA Astrophysics Data System (ADS)

    Schultz, Emeric

    2008-08-01

    A device that can demonstrate equilibrium, kinetic, and thermodynamic concepts is described. The device consists of a leaf blower attached to a plastic container divided into two chambers by a barrier of variable size and form. Styrofoam balls can be exchanged across the barrier when the leaf blower is turned on and various air pressures are applied. Equilibrium can be approached from different distributions of balls in the container under different conditions. The Le Châtelier principle can be demonstrated. Kinetic concepts can be demonstrated by changing the nature of the barrier, either changing the height or by having various sized holes in the barrier. Thermodynamic concepts can be demonstrated by taping over some or all of the openings and restricting air flow into container on either side of the barrier.

  9. Reliability and Correlation of Static and Dynamic Foot Arch Measurement in a Healthy Pediatric Population.

    PubMed

    Scholz, Timo; Zech, Astrid; Wegscheider, Karl; Lezius, Susanne; Braumann, Klaus-Michael; Sehner, Susanne; Hollander, Karsten

    2017-07-14

    Measurement of the medial longitudinal foot arch in children is a controversial topic, as there are many different methods without a definite standard procedure. The purpose of this study was to 1) investigate intraday and interrater reliability regarding dynamic arch index and static arch height, 2) explore the correlation between both arch indices, and 3) examine the variation of the medial longitudinal arch at two different times of the day. Eighty-six children (mean ± SD age, 8.9 ± 1.9 years) participated in the study. Dynamic footprint data were captured with a pedobarographic platform. For static arch measurements, a specially constructed caliper was used to assess heel-to-toe length and dorsum height. A mixed model was established to determine reliability and variation. Reliability was found to be excellent for the static arch height index in sitting (intraday, 0.90; interrater, 0.80) and standing positions (0.88 and 0.85) and for the dynamic arch index (both 1.00). There was poor correlation between static and dynamic assessment of the medial longitudinal arch (standing dynamic arch index, r = -0.138; sitting dynamic arch index, r = -0.070). Static measurements were found to be significantly influenced by the time of day (P < .001), whereas the dynamic arch index was unchanged (P = .845). This study revealed some further important findings. The static arch height index is influenced by gender (P = .004), whereas dynamic arch index is influenced by side (P = .011) and body mass index (P < .001). Dynamic and static foot measurements are reliable for medial longitudinal foot arch assessment in children. The variation of static arch measurements during the day has to be kept in mind. For clinical purposes, static and dynamic arch data should be interpreted separately.

  10. Solids Far from Equilibrium

    NASA Astrophysics Data System (ADS)

    Godrèche, C.

    2011-03-01

    Preface; 1. Shape and growth of crystals P. Nozières; 2. Instabilities of planar solidification fronts B. Caroli, C. Caroli and B. Roulet; 3. An introduction to the kinetics of first-order phase transition J. S. Langer; 4. Dendritic growth and related topics Y. Pomeau and M. Ben Amar; 5. Growth and aggregation far from equilibrium L. M. Sander; 6. Kinetic roughening of growing surfaces J. Krug and H. Spohn; Acknowledgements; References; Index.

  11. Non-equilibrium proteins.

    PubMed

    Klonowski, W

    2001-07-01

    There exist no methodical studies concerning non-equilibrium systems in cellular biology. This paper is an attempt to partially fill this shortcoming. We have undertaken an extensive data-mining operation in the existing scientific literature to find scattered information about non-equilibrium subcellular systems, in particular concerning fast proteins, i.e. those with short turnover half-time. We have advanced the hypothesis that functionality in fast proteins emerges as a consequence of their intrinsic physical instability that arises due to conformational strains resulting from co-translational folding (the interdependence between chain elongation and chain folding during biosynthesis on ribosomes). Such intrinsic physical instability, a kind of conformon (Klonowski-Klonowska conformon, according to Ji, (Molecular Theories of Cell Life and Death, Rutgers University Press, New Brunswick, 1991)) is probably the most important feature determining functionality and timing in these proteins. If our hypothesis is true, the turnover half-time of fast proteins should be positively correlated with their molecular weight, and some experimental results (Ames et al., J. Neurochem. 35 (1980) 131) indeed demonstrated such a correlation. Once the native structure (and function) of a fast protein macromolecule is lost, it may not be recovered--denaturation of such proteins will always be irreversible; therefore, we searched for information on irreversible denaturation. Only simulation and modeling of protein co-translational folding may answer the questions concerning fast proteins (Ruggiero and Sacile, Med. Biol. Eng. Comp. 37 (Suppl. 1) (1999) 363). Non-equilibrium structures may also be built up of protein subunits, even if each one taken by itself is in thermodynamic equilibrium (oligomeric proteins; sub-cellular sol-gel dissipative network structures).

  12. Molecular equilibrium with condensation

    NASA Astrophysics Data System (ADS)

    Sharp, C. M.; Huebner, W. F.

    1990-02-01

    Minimization of the Gibbs energy of formation for species of chemical elements and compounds in their gas and condensed phases determines their relative abundances in a mixture in chemical equilibrium. The procedure is more general and more powerful than previous abundance determinations in multiphase astrophysical mixtures. Some results for astrophysical equations of state are presented, and the effects of condensation on opacity are briefly indicated.

  13. Equilibrium Electroconvective Instability

    NASA Astrophysics Data System (ADS)

    Rubinstein, I.; Zaltzman, B.

    2015-03-01

    Since its prediction 15 years ago, hydrodynamic instability in concentration polarization at a charge-selective interface has been attributed to nonequilibrium electro-osmosis related to the extended space charge which develops at the limiting current. This attribution had a double basis. On the one hand, it has been recognized that neither equilibrium electro-osmosis nor bulk electroconvection can yield instability for a perfectly charge-selective solid. On the other hand, it has been shown that nonequilibrium electro-osmosis can. The first theoretical studies in which electro-osmotic instability was predicted and analyzed employed the assumption of perfect charge selectivity for the sake of simplicity and so did the subsequent studies of various time-dependent and nonlinear features of electro-osmotic instability. In this Letter, we show that relaxing the assumption of perfect charge selectivity (tantamount to fixing the electrochemical potential of counterions in the solid) allows for the equilibrium electroconvective instability. In addition, we suggest a simple experimental test for determining the true, either equilibrium or nonequilibrium, origin of instability in concentration polarization.

  14. Interrupted aortic arch: A misdiagnosed cause of hypertension.

    PubMed

    Ponte, Marta; Dias, Adelaide; Dias Ferreira, Nuno; Fonseca, Conceição; Mota, João Carlos; Gama, Vasco

    2014-06-01

    We present the case of a 47-year-old man with hypertension for over 20 years, referred to our hospital due to mild aortic dilatation detected on a transthoracic echocardiogram. On physical examination weak lower limb pulses and a blood pressure differential of >50 mmHg between arms and legs were detected. Complete interruption of the aortic arch below the left subclavian artery was diagnosed by computed tomography angiography. With this case we aim to draw attention to aortic coarctation and interrupted aortic arch as potential causes of hypertension and to highlight the importance of the physical examination in the diagnosis of secondary causes of hypertension.

  15. Full-arch milled titanium implant bridge: technical report.

    PubMed

    Peché, Wendy-Ann; Van Vuuren, Ludwig Jansen; Park, Chae

    2011-09-01

    The manufacturing of full-arch fixed implant-supported bridges with the use of the traditional lost wax technique remains a technical challenge. Distortion of the alloy during casting and subsequent heating cycles during porcelain build-up causes numerous problems. Fracturing of porcelain on large restorations is difficult and costly to restore. The fitting problems can be eliminated by utilising CAD/CAM technology in the manufacturing of long-span or full-arch titanium bridges. Repair of damaged porcelain can be simplified with the use of discrete, individually-removable crowns on the bridge.

  16. Preoperative Use of Radiopaque Materials on Fractured Zygomatic Arch.

    PubMed

    Koh, Sung Hoon; Kim, Hong Jin; Jung, Sung Won; Lim, Hyoseob

    2016-09-01

    Fractures of the zygoma are relatively frequent and their management has been extensively described. Above all, isolated zygomatic arch fractures comprise about 10% of all zygomatic fractures. Temporal approach is common surgical method, Gillies approach, but it has the limitation of blinded surgical approach. So, the mobile intraoperative fluoroscan is used famously for more suitable reduction, but it needs an additional man to control the machine and increases irradiation doses. The authors got the simple idea, but so helpful tool, and it has been performed since 2012. The authors have gotten good surgical results, so introduce this idea that favors the surgery on isolated zygomatic arch fracture.

  17. 10. VIEW SHOWING THE ARCH FORMS. THE INTRADOS FORM IS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. VIEW SHOWING THE ARCH FORMS. THE INTRADOS FORM IS COMMONLY LIFTED 3 TO 4 DAYS AFTER POURING. REINFORCING STEEL IS THEN PLACED AND THE EXTRADOS FORM RAISED TO POSITION. THE OPERATING OF MOVING FORMS, PLACING STEEL AND CONCRETE FOR EACH ARCH LIFT REQUIRES, ON AVERAGE, EIGHT DAYS. NOTE THE TWO LINES OF WATER PIPE ON THE EXTRADOS FORM. THESE PIPES ARE FILLED WITH SPRAY NOZZLES WHICH ARE IN PRACTICALLY CONTINUOUS OPERATION EXCEPT WHEN WORK IS BEING DONE ON THE FORMS. August 9, 1938 - Bartlett Dam, Verde River, Phoenix, Maricopa County, AZ

  18. Multimodality imaging assessment for Thoraflex hybrid total arch replacement.

    PubMed

    Wong, Randolph Hl; Ho, Jacky Yk; Underwood, Malcolm J

    2016-06-01

    Conventionally, aortic pathologies involving the ascending, arch, and descending thoracic aorta are treated by a staged operation. The Thoraflex device is a composite 4-branched graft with a distal endovascular stent, which allows one-stage treatment of these pathologies. We describe our multimodality hybrid approach for total arch replacement using the Thoraflex device with the adjunct of intraoperative 3-dimensional transesophageal echocardiography, Endo-EYE endoscopy, and on-table aortography in a hybrid operating room. These multimodality assessments can ascertain adequate sealing of a distal aortic tear and proper opening of the endograft, and provide on-table functional assessment of false lumen hemodynamics. Early results are promising.

  19. Concomitant reconstruction of arch vessels during repair of aortic dissection.

    PubMed

    Micovic, Slobodan; Nezic, Dusko; Vukovic, Petar; Jovanovic, Marko; Lozuk, Branko; Jagodic, Sinisa; Djukanovic, Bosko

    2014-08-01

    Surgery for acute aortic dissection is challenging, especially in cases of cerebral malperfusion. Should we perform only the aortic repair, or should we also reconstruct the arch vessels when they are severely affected by the disease process? Here we present a case of acute aortic dissection with multiple tears that involved the brachiocephalic artery and caused cerebral and right upper-extremity malperfusion. The patient successfully underwent complete replacement of the brachiocephalic artery and the aortic arch during deep hypothermic circulatory arrest, with antegrade cerebral protection. We have found this technique to be safe and reproducible for use in this group of patients.

  20. Polynomial and catenary curve fits to human dental arches.

    PubMed

    Pepe, S H

    1975-01-01

    Polynomial and catenary equations were fit by least square error methods to the dentitions of seven children with "normal" occlusion. Mean and mean square error were then used to analyze accuracy of curve fits and asymmetries of arches. A lack of congruency for the "lines of occlusion" common to the maxilla and mandible suggest that the defining anatomic landmarks are inaccurate. These analyses show that the coefficients of the sixth degree polynomial equations appear to have potential as clinical indicators of arch form and, perhaps, malocclusion.

  1. Endovascular Stent Grafting for Aortic Arch Aneurysm in Aortoiliac Occlusive Disease following Aortic Arch Debranching and Aortobifemoral Reconstruction

    PubMed Central

    Canbay, Cagla; Onal, Yilmaz; Beyaz, Metin Onur; Sayin, Omer Ali; Barburoglu, Mehmet; Yornuk, Mesut; Acunas, Bulent; Alpagut, Ufuk; Dayioglu, Enver

    2017-01-01

    Treatment of thoracic aortic aneurysms constitutes high mortality and morbidity rates despite improvements in surgery, anesthesia, and technology. Endovascular stent grafting may be an alternative therapy with lower risks when compared with conventional techniques. However, sometimes the branches of the aortic arch may require transport to the proximal segments prior to successful thoracic aortic endovascular stent grafting. Atherosclerosis is accounted among the etiology of both aneurysms and occlusive diseases that can coexist in the same patient. In these situations stent grafting may even be more complicated. In this report, we present the treatment of a 92-year-old patient with aortic arch aneurysm and proximal descending aortic aneurysm. For successful thoracic endovascular stent grafting, the patient needed an alternative route other than the native femoral and iliac arteries for the deployment of the stent graft. In addition, debranching of left carotid and subclavian arteries from the aortic arch was also required for successful exclusion of the thoracic aneurysm. PMID:28408933

  2. 4. 3/4 VIEW OF ARCH OVER ROADWAY AT SOUTH END ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    4. 3/4 VIEW OF ARCH OVER ROADWAY AT SOUTH END OF SPAN, LOOKING SW, SHOWING RIBBED ARCH CONSTRUCTION. - Philadelphia & Reading Railroad, Peacock's Lock Viaduct, Spanning Schuykill River at Reading Railroad, Reading, Berks County, PA

  3. Thoracoscopic Resection of a Rare Case of Hemangioma of the Azygos Venous Arch

    PubMed Central

    Yixin, Cai; Ni, Zhang; Wenxin, Wang

    2017-01-01

    Hemangioma of the azygos venous arch is an exceedingly rare incident. This is a case of a thoracoscopic complete resection of a hemangioma of the azygos venous arch in a 37-year-old woman. PMID:28367348

  4. Percutaneous Pediculoplasty for Vertebral Hemangioma Involving the Neural Arch: A Case Report

    SciTech Connect

    Fuwa, Sokun Numaguchi, Yuji; Kobayashi, Nobuo; Saida, Yukihisa

    2008-01-15

    Vertebral hemangiomas occasionally involve the neural arch and they can be symptomatic. We report a case of symptomatic vertebral hemangioma mainly involving the unilateral neural arch which was successfully treated with percutaneous pediculoplasty using a single-needle technique.

  5. Structural design using equilibrium programming

    NASA Technical Reports Server (NTRS)

    Scotti, Stephen J.

    1992-01-01

    Multiple nonlinear programming methods are combined in the method of equilibrium programming. Equilibrium programming theory has been appied to problems in operations research, and in the present study it is investigated as a framework to solve structural design problems. Several existing formal methods for structural optimization are shown to actually be equilibrium programming methods. Additionally, the equilibrium programming framework is utilized to develop a new structural design method. Selected computational results are presented to demonstrate the methods.

  6. INTERIOR DETAIL, SECONDSTORY JOISTS, SUBFLOORING, AND FIREPLACE HEARTH RELIEVING ARCH. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    INTERIOR DETAIL, SECOND-STORY JOISTS, SUBFLOORING, AND FIREPLACE HEARTH RELIEVING ARCH. THESE FEATURES WERE MADE VISIBLE AFTER A 2002 FAILURE OF WHAT WAS LIKELY THE ORIGINAL EIGHTEENTH-CENTURY CEILING PLASTER IN THE SOUTHWEST CABINET - The Woodlands, 4000 Woodlands Avenue, Philadelphia, Philadelphia County, PA

  7. 6. OPEN HEARTH NO. 4 TRESTLE. THE ARCH WITH THE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. OPEN HEARTH NO. 4 TRESTLE. THE ARCH WITH THE GATE IS KNOWN AS THE HOLE IN THE WALL BY FORMER STEELWORKERS. FOR YEARS THE HOLE IN THE WALL PROVIDED ACCESS TO THE INTERIOR OF THE MILL AND TO THE PAYMASTER'S OFFICE. (Martin Stupich) - U.S. Steel Homestead Works, Open Hearth Steelmaking Plant, Along Monongahela River, Homestead, Allegheny County, PA

  8. Arch Venture Partners' investment considerations for CBRNE products and opportunities

    NASA Astrophysics Data System (ADS)

    Crandell, K.; Lazarus, S.; Gardner, P. J.

    2008-04-01

    ARCH is interested in building leading, highly-valued companies from leading research. Toward that end we value innovations created by the leading researchers in the world, many of which are funded to solve critical scientific challenges including those in the instrumentation and CBRNE area. The most important CBRNE innovations we have seen at ARCH are breakthroughs involving significant unaddressed technology risk and have the potential for broad proprietary intellectual property as a result. The model ARCH has evolved in instrumentation is to look for a breakthrough innovation, with strong intellectual property and continue to strengthen the patent estate through the life of the company. ARCH looks to build companies around leading interdisciplinary scientific and engineering teams, and we favor platform technology that can be applied to multiple market applications both commercial and government. As part of a strategy to build a great company, addressing important CBRNE challenges can help a company strengthen its technical team and its IP estate. This supports a focus on early low volume markets on the way toward addressing a fuller portfolio of applications. Experienced Venture Capitalists can help this process by identifying important executive talent, partners and applications, offering financial syndication strength, and helping shape the company's strategy to maximize the ultimate value realized.

  9. Huge ascending aorta and aortic arch aneurysm in ultra octogenarian.

    PubMed

    Ceresa, F; Sansone, F; Zagarella, G; Patanè, F

    2014-01-01

    Giant ascending aorta aneurysms (AAA), which are larger than 10 cm, are rarely been reported (1-7). We hereby present the case of a giant AAA of about 11 cm in a very old women who was successfully operated on for ascending aorta and aortic arch replacement under deep hypothermic circulatory arrest.

  10. Height of the Medial Longitudinal Arch During Classical Ballet Steps.

    PubMed

    de Mello Viero, Carolina Cabral; Kessler, Luíza Pillar; Pinto, Camila; Gontijo, Kaanda Nabilla Souza; da Rosa, Rodrigo Gomes; Kleiner, Ana; Peyré-Tartaruga, Leonardo Alexandre; do Pinho, Alexandre Severo; de Souza Pagnussat, Aline

    2017-09-15

    The purpose of this study was to evaluate the midfoot longitudinal arch height and correlate it with active hip external rotation (ER) in dancers during static postures and technical steps of classical ballet (i.e., first position, demi-plié, battement fondu à la seconde, pas jeté à la seconde, and grand jeté à la seconde). A 3D motion analysis system was used for kinematic analysis. The arch height was significantly reduced during the battement fondu à la seconde, pas jeté à la seconde, and grand jeté à la seconde when compared to standing (p = 0.000 for all comparisons), first position (p = 0.000, p = 0.000, and p = 0.001, respectively) and demi-plié (p = 0.015, p = 0.003, and p = 0.006, respectively). No significant correlation was found between arch height and active hip external rotation (p > 0.05). Hence, active hip external rotation does not seem to be related to midfoot pronation in this sample. Other factors, such as intrinsic and extrinsic foot muscle strength, may be related to the midfoot arch height. These findings contribute to a better understanding of ballet steps, but future studies are required to clarify this topic completely.

  11. View of openspandrel concrete arch that carries the road crossing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    View of open-spandrel concrete arch that carries the road crossing Grand Coulee Dam over the spillways, looking west. Note the drum gate in its nearly fully raised position. - Columbia Basin Project, Grand Coulee Dam & Franklin D. Roosevelt Lake, Across Columbia River, Southeast of Town of Grand Coulee, Grand Coulee, Grant County, WA

  12. Southeast view of the no. 1 outside diameter submerged arch ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Southeast view of the no. 1 outside diameter submerged arch welder of the saw line in bay 8 of the main pipe mill building. - U.S. Steel National Tube Works, Main Pipe Mill Building, Along Monongahela River, McKeesport, Allegheny County, PA

  13. 6. View of mill wall ruins looking E showing arched ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    6. View of mill wall ruins looking E showing arched openings where fuel was fed to fire Jamaican Train. - Hacienda Azucarera La Esperanza, Mill (Ruins), 2.65 miles North of PR Route 2 Bridge Over Manati River, Manati, Manati Municipio, PR

  14. 10. View looking S at large arched opening that led ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. View looking S at large arched opening that led from area where Jamaican Train was fired to steam engine and cane mill. - Hacienda Azucarera La Esperanza, Mill (Ruins), 2.65 miles North of PR Route 2 Bridge Over Manati River, Manati, Manati Municipio, PR

  15. 35. Photo of concrete arch culvert constructed by Puget Sound ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    35. Photo of concrete arch culvert constructed by Puget Sound Construction Company, 1911, for the Northern Pacific Railroad, over flume. Photo by Brian C. Morris, Puget Power, 1989. - Puget Sound Power & Light Company, White River Hydroelectric Project, 600 North River Avenue, Dieringer, Pierce County, WA

  16. VIEW OF UNDERSIDE OF BRIDGE, SHOWING RELATIONSHIP BETWEEN ARCH RIBS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    VIEW OF UNDERSIDE OF BRIDGE, SHOWING RELATIONSHIP BETWEEN ARCH RIBS AND ARRANGEMENT OF PRECAST RIB STRUTS. MILL AVENUE BRIDGE AND TEMPE BUTTE ARE SEEN IN THE BACKGROUND - Ash Avenue Bridge, Spanning Salt River at Foot of Ash Avenue, Tempe, Maricopa County, AZ

  17. Towering Magnetic Arches Seen by NASA’s SDO

    NASA Image and Video Library

    Arches of magnetic field lines towered over the sun’s edge as a pair of active regions began to rotate into view in this video captured by NASA’s Solar Dynamics Observatory on April 5-6, 2016. Acti...

  18. Detail of typical subdeck of granite pier showing humanscale arched ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Detail of typical subdeck of granite pier showing human-scale arched openings in pies. Note remnants of fender system. View north - New York, New Haven & Hartford Railroad, Fort Point Channel Rolling Lift Bridge, Spanning Fort Point Channel, Boston, Suffolk County, MA

  19. 3D Stretchable Arch Ribbon Array Fabricated via Grayscale Lithography

    NASA Astrophysics Data System (ADS)

    Pang, Yu; Shu, Yi; Shavezipur, Mohammad; Wang, Xuefeng; Mohammad, Mohammad Ali; Yang, Yi; Zhao, Haiming; Deng, Ningqin; Maboudian, Roya; Ren, Tian-Ling

    2016-06-01

    Microstructures with flexible and stretchable properties display tremendous potential applications including integrated systems, wearable devices and bio-sensor electronics. Hence, it is essential to develop an effective method for fabricating curvilinear and flexural microstructures. Despite significant advances in 2D stretchable inorganic structures, large scale fabrication of unique 3D microstructures at a low cost remains challenging. Here, we demonstrate that the 3D microstructures can be achieved by grayscale lithography to produce a curved photoresist (PR) template, where the PR acts as sacrificial layer to form wavelike arched structures. Using plasma-enhanced chemical vapor deposition (PECVD) process at low temperature, the curved PR topography can be transferred to the silicon dioxide layer. Subsequently, plasma etching can be used to fabricate the arched stripe arrays. The wavelike silicon dioxide arch microstructure exhibits Young modulus and fracture strength of 52 GPa and 300 MPa, respectively. The model of stress distribution inside the microstructure was also established, which compares well with the experimental results. This approach of fabricating a wavelike arch structure may become a promising route to produce a variety of stretchable sensors, actuators and circuits, thus providing unique opportunities for emerging classes of robust 3D integrated systems.

  20. 14. CELLAR, CENTER BAY, LOOKING NORTH. Ahead is the arched ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. CELLAR, CENTER BAY, LOOKING NORTH. Ahead is the arched support of the furnace smoke flue traveling westward from the brick furnace centered under the main meeting room to the vertical flue at the partition between the two meeting rooms. - Twelfth Street Meeting House, 20 South Twelfth Street, Philadelphia, Philadelphia County, PA

  1. Stereological Analysis of Bone Architecture in the Pig Zygomatic Arch

    PubMed Central

    Teng, Shengyi; Choi, In W.; Herring, Susan W.; Rensberger, John M.

    2010-01-01

    Background Stereological analysis of trabecular bone structure may reveal information about regional variations in stress distribution, especially in areas like the zygomatic arch in which those variations are difficult to assess mechanically. This study investigates regional differences in trabecular orientation, thickness, and density in the zygomatic and squamosal bones of pigs. Methods Zygomatic arches were serially sectioned frontally (n = 4), horizontally (n = 4), or parasagittally (n = 4), at a thickness of 0.8 mm. Sections were viewed under a stereomicroscope; video-images were digitized and analyzed with an automated program. Results All regions were anisotropic. Predominant orientation of trabeculae differed between and within bones. Three main patterns were seen. Anteriorly, zygomatic trabeculae were mainly arranged vertically and anteroposteriorly (relative to the occlusal plane). Posteriorly, including the jaw joint region, the squamosal featured primarily mediolateral trabeculae. In the midsection of the arch, where the two bones overlap, the trabeculae displayed a predominantly anteroposterior orientation with a secondary mediolateral peak. Trabeculae were typically 0.3–0.4 mm wide and occupied 40–50% of the area of the sections with few regional variations. Conclusions Trabecular bone in the pig zygomatic arch is arranged orthogonally, relative to the occlusal plane. In conjunction with information from strain gauge recording, these data suggest that the zygomatic bone is bent in the parasagittal plane whereas the squamosal is bent out-of-plane. The mediolateral trabeculae in the posterior regions are consistent with a cantilever effect at the jaw joint. PMID:9185986

  2. EARTH-COVERED, STEEL-ARCH MAGAZINE TESTS.

    DTIC Science & Technology

    A series of tests of earth-covered, steel-arch igloo magazines was conducted to determine the minimum spacing distance between adjacent igloos needed...to prevent the propagation of an explosion from one magazine to another. It was shown that the distance in feet between the side walls can be

  3. 7. DETAIL, LOOKING SOUTH, INTERIOR OF SOUTH ARCH, SHOWING DRAINAGE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    7. DETAIL, LOOKING SOUTH, INTERIOR OF SOUTH ARCH, SHOWING DRAINAGE HOLE IN THE WEST END OF THE SOUTH WALL AND VERTICAL QUARRY DRILLING HOLES ON THE STONE FACE - Mulladay Hollow Bridge, Spanning Mulladay Hollow Creek at County Road No.61, Eureka Springs, Carroll County, AR

  4. Missed C1 posterior arch fracture: a case report

    PubMed Central

    Munro, Donald S

    1990-01-01

    A case of a C1 posterior arch fracture following a fall is presented. The need to perform a thorough history and examination, regardless of previous examination findings, is emphasized. This is especially true when there is a history of recent trauma. A brief discussion of the characteristics and management of C1 fractures follows. ImagesFigure 1Figure 2Figure 3

  5. 1. GORGE HIGH DAM. THIS THIN ARCH DAM WITH A ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. GORGE HIGH DAM. THIS THIN ARCH DAM WITH A GRAVITY SECTION IS THE THIRD DAM BUILT BY SEATTLE CITY LIGHT TO PROVIDE WATER FOR GORGE POWERHOUSE AND WAS COMPLETED IN 1961, 1989. - Skagit Power Development, Gorge High Dam, On Skagit River, 2.9 miles upstream from Newhalem, Newhalem, Whatcom County, WA

  6. 14. Detail, northeast facade, arched main window of waiting room; ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. Detail, northeast facade, arched main window of waiting room; note quality of stonework and mortar joint tooling beneath window, representing a ca. 1937 alteration; view to southwest, 90mm lens. - Southern Pacific Depot, 559 El Camino Real, San Carlos, San Mateo County, CA

  7. 3D Stretchable Arch Ribbon Array Fabricated via Grayscale Lithography

    PubMed Central

    Pang, Yu; Shu, Yi; Shavezipur, Mohammad; Wang, Xuefeng; Mohammad, Mohammad Ali; Yang, Yi; Zhao, Haiming; Deng, Ningqin; Maboudian, Roya; Ren, Tian-Ling

    2016-01-01

    Microstructures with flexible and stretchable properties display tremendous potential applications including integrated systems, wearable devices and bio-sensor electronics. Hence, it is essential to develop an effective method for fabricating curvilinear and flexural microstructures. Despite significant advances in 2D stretchable inorganic structures, large scale fabrication of unique 3D microstructures at a low cost remains challenging. Here, we demonstrate that the 3D microstructures can be achieved by grayscale lithography to produce a curved photoresist (PR) template, where the PR acts as sacrificial layer to form wavelike arched structures. Using plasma-enhanced chemical vapor deposition (PECVD) process at low temperature, the curved PR topography can be transferred to the silicon dioxide layer. Subsequently, plasma etching can be used to fabricate the arched stripe arrays. The wavelike silicon dioxide arch microstructure exhibits Young modulus and fracture strength of 52 GPa and 300 MPa, respectively. The model of stress distribution inside the microstructure was also established, which compares well with the experimental results. This approach of fabricating a wavelike arch structure may become a promising route to produce a variety of stretchable sensors, actuators and circuits, thus providing unique opportunities for emerging classes of robust 3D integrated systems. PMID:27345766

  8. 37. Detail view of center of castiron arch in N ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    37. Detail view of center of cast-iron arch in N room of mill. - Hacienda Azurarera Santa Elena, Sugar Mill Ruins, 1.44 miles North of PR Route 2 Bridge Over Rio De La Plata, Toa Baja, Toa Baja Municipio, PR

  9. 32. Symmetrical view of castiron columns and arches, looking W, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    32. Symmetrical view of cast-iron columns and arches, looking W, in interior of N room of mill. - Hacienda Azurarera Santa Elena, Sugar Mill Ruins, 1.44 miles North of PR Route 2 Bridge Over Rio De La Plata, Toa Baja, Toa Baja Municipio, PR

  10. 43. Detail view of connection between column top and arch ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    43. Detail view of connection between column top and arch in S room. - Hacienda Azurarera Santa Elena, Sugar Mill Ruins, 1.44 miles North of PR Route 2 Bridge Over Rio De La Plata, Toa Baja, Toa Baja Municipio, PR

  11. 3. West end. Note arched basement entrance at north half ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    3. West end. Note arched basement entrance at north half of west endwall. Sand tower (MN-99-E) at right. View to east. - Duluth & Iron Range Rail Road Company Shops, Oil House, Southwest of downtown Two Harbors, northwest of Agate Bay, Two Harbors, Lake County, MN

  12. 30. 'Details Of Caisson For Piers For Three Hinged Arch ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    30. 'Details Of Caisson For Piers For Three Hinged Arch Bridge Over Yuba River, Thomas System, Thomas And Post, Engineers, Hibernian Bldg., Los Angeles, Revised Oct. 22, 1912.' - Parks Bar Bridge, Spanning Yuba River at State Highway 20, Smartville, Yuba County, CA

  13. Strengthening of certain types of arch dams at broad sites

    SciTech Connect

    Kaganov, G. M.; Volkov, V. I.; Uchevatkin, A. A.

    2012-01-15

    The problem of strengthening defective and damaged arch dams is formulated, and methodical calculations are performed to substantiate a set of structural and production measures permitting substantial improvement in the stress-strain state and an increase in the safety factor of the structure. Feasibility of practical implementation of the results is foreseen.

  14. 12. DETAIL VIEW OF BUTTRESS 8 AND HALF OF ARCH ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. DETAIL VIEW OF BUTTRESS 8 AND HALF OF ARCH 7. THE IMPRESSIONS OF THE WOODEN FORMS ARE VISIBLE ON THE CONCRETE. ALSO VISIBLE IS THE PLACEMENT OF THE DAM DIRECTLY ON BEDROCK. - Hume Lake Dam, Sequioa National Forest, Hume, Fresno County, CA

  15. Double arch mirror study. Part 2: Engineering analysis report

    NASA Technical Reports Server (NTRS)

    Iraninejad, B.; Vukobratovich, D.

    1983-01-01

    A method of mounting a cryogenically cooled, lightweight, double arch, class mirror for infrared, astronomical telescopes was developed. A 50 cm, fused silica mirror was modified for use in a new mount configuration. The flexures and the finite element analysis of the mirror stresses are reported.

  16. How to Perfuse: Concepts of Cerebral Protection during Arch Replacement

    PubMed Central

    Habertheuer, Andreas; Wiedemann, Dominik; Kocher, Alfred; Laufer, Guenther; Vallabhajosyula, Prashanth

    2015-01-01

    Arch surgery remains undoubtedly among the most technically and strategically challenging endeavors in cardiovascular surgery. Surgical interventions of thoracic aneurysms involving the aortic arch require complete circulatory arrest in deep hypothermia (DHCA) or elaborate cerebral perfusion strategies with varying degrees of hypothermia to achieve satisfactory protection of the brain from ischemic insults, that is, unilateral/bilateral antegrade cerebral perfusion (ACP) and retrograde cerebral perfusion (RCP). Despite sophisticated and increasingly individualized surgical approaches for complex aortic pathologies, there remains a lack of consensus regarding the optimal method of cerebral protection and circulatory management during the time of arch exclusion. Many recent studies argue in favor of ACP with various degrees of hypothermic arrest during arch reconstruction and its advantages have been widely demonstrated. In fact ACP with more moderate degrees of hypothermia represents a paradigm shift in the cardiac surgery community and is widely adopted as an emergent strategy; however, many centers continue to report good results using other perfusion strategies. Amidst this important discussion we review currently available surgical strategies of cerebral protection management and compare the results of recent European multicenter and single-center data. PMID:26713319

  17. 18. Upstream face of arches, concrete placing tower is at ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    18. Upstream face of arches, concrete placing tower is at far right. Tower at center was used to convey material. Photographer unknown, January 29, 1927. Source: MWD. - Waddell Dam, On Agua Fria River, 35 miles northwest of Phoenix, Phoenix, Maricopa County, AZ

  18. “Open” approach to aortic arch aneurysm repair☆

    PubMed Central

    Al Kindi, Adil H.; Al Kimyani, Nasser; Alameddine, Tarek; Al Abri, Qasim; Balan, Baskaran; Al Sabti, Hilal

    2014-01-01

    Aortic arch aneurysm is a relatively rare entity in cardiac surgery. Repair of such aneurysms, either in isolation or combined with other cardiac procedures, remains a challenging task. The need to produce a relatively bloodless surgical field with circulatory arrest, while at the same time protecting the brain, is the hallmark of this challenge. However, a clear understanding of the topic allows a better and less morbid approach to such a complex surgery. Literature has shown the advantage of selective cerebral perfusion techniques in comparison with only circulatory arrest. Ability to perfuse the brain has allowed circulatory arrest temperatures at moderate hypothermia without the need for deep hypothermia. Even though cannulation site selection appears to be a minor issue, literature has shown that the subclavian/axillary route has the best outcomes and that femoral cannulation should only be reserved for no access patients. Although different techniques for arch anastomosis have been described, we routinely perform the distal first technique as we find it to be less cumbersome and easiest to reproduce. In this review our aim is to outline a systematic approach to aortic arch surgery. Starting with indications for intervention and proceeding with approaches on site of cannulation, approaches to brain protection with hypothermia and selective cerebral perfusion and finally surgical steps in performing the distal and arch vessels anastomosis. PMID:24954988

  19. Bare Metal Stenting for Endovascular Exclusion of Aortic Arch Thrombi

    SciTech Connect

    Mahnken, Andreas H.; Hoffman, Andras; Autschbach, Ruediger; Damberg, Anneke L. M.

    2013-08-01

    BackgroundAortic thrombi in the ascending aorta or aortic arch are rare but are associated with a relevant risk of major stroke or distal embolization. Although stent grafting is commonly used as a treatment option in the descending aorta, only a few case reports discuss stenting of the aortic arch for the treatment of a thrombus. The use of bare metal stents in this setting has not yet been described.MethodsWe report two cases of ascending and aortic arch thrombus that were treated by covering the thrombus with an uncovered stent. Both procedures were performed under local anesthesia via a femoral approach. A femoral cutdown was used in one case, and a total percutaneous insertion was possible in the second case.ResultsBoth procedures were successfully performed without any periprocedural complications. Postoperative recovery was uneventful. In both cases, no late complications or recurrent embolization occurred at midterm follow-up, and control CT angiography at 1 respectively 10 months revealed no stent migration, freely perfused supra-aortic branches, and no thrombus recurrence.ConclusionTreating symptomatic thrombi in the ascending aorta or aortic arch with a bare metal stent is feasible. This technique could constitute a minimally invasive alternative to a surgical intervention or complex endovascular therapy with fenestrated or branched stent grafts.

  20. 2. CONTEXT SHOT LOOKING NORTH, WITH BUILDING 8250 (ARCH HANGAR ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. CONTEXT SHOT LOOKING NORTH, WITH BUILDING 8250 (ARCH HANGAR IN BACKGROUND AND STEAM PIPES BENDING OVER RAILROAD TRACKS IN MIDDLE GROUND. - Loring Air Force Base, Double Cantilever Hangar, East of Arizona Road, west of southern portion of Taxiway J, Limestone, Aroostook County, ME

  1. 10. MARBLE BRIDGE MIDSPAN OF EAST ARCH. THE PLATE READS ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. MARBLE BRIDGE MIDSPAN OF EAST ARCH. THE PLATE READS MORRIS RUN BRIDGE, 1908, C.F. MOYER, C.Y. STRADLINGS, S.M. FITE, COMMRR'S, S.B. TWINING CO. CONTR, W. CADWALLADER CLERK. - Morris Run Bridge, Rickert Road (TR 417) spanning Morris Run in Hilltown Township, Dublin, Bucks County, PA

  2. 10. Hingepin connection of arch structural member to concrete footing ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    10. Hinge-pin connection of arch structural member to concrete footing on east of south end of bridge. Slightly oblique detail view west-northwest (from beside bridge). 150 mm lens. - Gault Bridge, Spanning Deer Creek at South Pine Street, Nevada City, Nevada County, CA

  3. 14. Reinforced Concrete Arch over Truckee River at Reno, Nevada. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    14. Reinforced Concrete Arch over Truckee River at Reno, Nevada. January 24, 1920. C. R. Hill, Consulting Engineer, Reno, Nevada. Various plan, section, and detail views. Paper (same as NV-10-13). Drawing No. B-72 (VB-10-25) - Riverside Bridge, Spanning Truckee River at Booth Street, Reno, Washoe County, NV

  4. 11. Connection of upright structural members to top of arch ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    11. Connection of upright structural members to top of arch member on east side of north end of bridge. Oblique detail view southwest (from beside bridge). 360 mm lens. - Gault Bridge, Spanning Deer Creek at South Pine Street, Nevada City, Nevada County, CA

  5. 15. Reinforced Concrete Arch over Truckee River at Reno, Nevada. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    15. Reinforced Concrete Arch over Truckee River at Reno, Nevada. January 28, 1920. C. R. Hill, Consulting Engineer, Reno, Nevada. Various sectional and detail views of railings. lamp posts, and brackets. Paper (same as NV-10-13 and NV-10-14). Drawing No. B-73 (VB-10-26). - Riverside Bridge, Spanning Truckee River at Booth Street, Reno, Washoe County, NV

  6. 12. Reinforced Concrete Arch over Truckee River at Reno, Nevada. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    12. Reinforced Concrete Arch over Truckee River at Reno, Nevada. January 21, 1920. C. R. Hill, Consulting Engineer, Reno, Nevada. Plan and Elevation of East Side. Paper (white on blue). Drawing No. B-71 (VA-7-5). - Riverside Bridge, Spanning Truckee River at Booth Street, Reno, Washoe County, NV

  7. 9. Terminal connection of arch structural member to concrete abutment ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    9. Terminal connection of arch structural member to concrete abutment on east of south end of bridge. Slightly oblique detail view west-northwest (from beside bridge). 150 mm lens. - Gault Bridge, Spanning Deer Creek at South Pine Street, Nevada City, Nevada County, CA

  8. 49 CFR 230.61 - Arch tubes, water bar tubes, circulators and thermic siphons.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Arch tubes, water bar tubes, circulators and... MAINTENANCE STANDARDS Boilers and Appurtenances Washing Boilers § 230.61 Arch tubes, water bar tubes, circulators and thermic siphons. (a) Frequency of cleaning. Each time the boiler is washed, arch tubes...

  9. 49 CFR 230.61 - Arch tubes, water bar tubes, circulators and thermic siphons.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Arch tubes, water bar tubes, circulators and... MAINTENANCE STANDARDS Boilers and Appurtenances Washing Boilers § 230.61 Arch tubes, water bar tubes, circulators and thermic siphons. (a) Frequency of cleaning. Each time the boiler is washed, arch tubes...

  10. 49 CFR 230.61 - Arch tubes, water bar tubes, circulators and thermic siphons.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Arch tubes, water bar tubes, circulators and... MAINTENANCE STANDARDS Boilers and Appurtenances Washing Boilers § 230.61 Arch tubes, water bar tubes, circulators and thermic siphons. (a) Frequency of cleaning. Each time the boiler is washed, arch tubes...

  11. 49 CFR 230.61 - Arch tubes, water bar tubes, circulators and thermic siphons.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Arch tubes, water bar tubes, circulators and... MAINTENANCE STANDARDS Boilers and Appurtenances Washing Boilers § 230.61 Arch tubes, water bar tubes, circulators and thermic siphons. (a) Frequency of cleaning. Each time the boiler is washed, arch tubes...

  12. Comparison of arch form between ethnic Malays and Malaysian Aborigines in Peninsular Malaysia

    PubMed Central

    Xinwei, Eunice Soh; Lim, Sheh Yinn; Jamaludin, Marhazlinda; Mohamed, Nor Himazian; Yusof, Zamros Yuzaidi Mohd; Shoaib, Lily Azura; Nik Hussein, Nik Noriah

    2012-01-01

    Objective To determine and compare the frequency distribution of various arch shapes in ethnic Malays and Malaysian Aborigines in Peninsular Malaysia and to investigate the morphological differences of arch form between these two ethnic groups. Methods We examined 120 ethnic Malay study models (60 maxillary, 60 mandibular) and 129 Malaysian Aboriginal study models (66 maxillary, 63 mandibular). We marked 18 buccal tips and incisor line angles on each model, and digitized them using 2-dimensional coordinate system. Dental arches were classified as square, ovoid, or tapered by printing the scanned images and superimposing Orthoform arch templates on them. Results The most common maxillary arch shape in both ethnic groups was ovoid, as was the most common mandibular arch shape among ethnic Malay females. The rarest arch shape was square. Chi-square tests, indicated that only the distribution of the mandibular arch shape was significantly different between groups (p = 0.040). However, when compared using independent t-tests, there was no difference in the mean value of arch width between groups. Arch shape distribution was not different between genders of either ethnic group, except for the mandibular arch of ethnic Malays. Conclusions Ethnic Malays and Malaysian Aborigines have similar dental arch dimensions and shapes. PMID:23112931

  13. Are embrasure wires better than arch bars for intermaxillary fixation?

    PubMed

    Tracy, Kyle; Gutta, Rajesh

    2015-01-01

    To compare the outcomes of mandible fractures treated with open reduction and internal fixation versus adjunctive intermaxillary fixation (IMF) using 2 different techniques. We performed a retrospective medical record review. The medical records of consecutive patients with mandible fractures treated surgically with adjunctive use of IMF (embrasure wires vs arch bars) were reviewed for demographic data, etiology, fracture location, antibiotic use, and interval to repair. Specifically, the complications, including infection, malunion or nonunion, hardware failure, and wound dehiscence, were recorded. The data were analyzed using Student's t test and the chi-square test or Fisher's exact test, as appropriate. Statistical significance was set at P < .05. A descriptive cost analysis was also performed and compared with those from previously published studies. The data from 86 subjects were included in the present study. Of the 86 subjects, 33 were in the embrasure wire group and 53 in the arch bar group. Of the patients in the arch bar group, 26% had complications compared with 15% in the embrasure wire IMF group. No statistically significant difference between the groups in terms of infection (P = .63), hardware failure (P = .75), malocclusion (P = .85), and nonunion (P = 1.0). However, the cost of arch bar placement and removal was approximately $2,672 more than the placement of embrasure wires. Patients treated with embrasure wire IMF had slightly better clinical outcomes compared with those treated with arch bar IMF. Also, the cost reduction for patients treated with embrasure wire IMF was significant. Copyright © 2015 American Association of Oral and Maxillofacial Surgeons. Published by Elsevier Inc. All rights reserved.

  14. Three-Dimensional Stiffness of the Carpal Arch

    PubMed Central

    Gabra, Joseph N.; Li, Zong-Ming

    2015-01-01

    The carpal arch of the wrist is formed by irregularly shaped carpal bones interconnected by numerous ligaments, resulting in complex structural mechanics. The purpose of this study was to determine the three-dimensional stiffness characteristics of the carpal arch using displacement perturbations. It was hypothesized that the carpal arch would exhibit an anisotropic stiffness behavior with principal directions that are oblique to the conventional anatomical axes. Eight (n = 8) cadavers were used in this study. For each specimen, the hamate was fixed to a custom stationary apparatus. An instrumented robot arm applied three-dimensional displacement perturbations to the ridge of trapezium and corresponding reaction forces were collected. The displacement-force data were used to determine a three-dimensional stiffness matrix using least squares fitting. Eigendecomposition of the stiffness matrix was used to identify the magnitudes and directions of the principal stiffness components. The carpal arch structure exhibited anisotropic stiffness behaviors with a maximum principal stiffness of 16.4 ± 4.6 N/mm that was significantly larger than the other principal components of 3.1 ± 0.9 and 2.6 ± 0.5 N/mm (p < 0.001). The principal direction of the maximum stiffness was pronated within the cross section of the carpal tunnel which is accounted for by the stiff transverse ligaments that tightly bind distal carpal arch. The minimal principal stiffness is attributed to the less constraining articulation between the trapezium and scaphoid. This study provides advanced characterization of the wrist's three-dimensional structural stiffness for improved insight into wrist biomechanics, stability, and function. PMID:26617368

  15. Three-dimensional stiffness of the carpal arch.

    PubMed

    Gabra, Joseph N; Li, Zong-Ming

    2016-01-04

    The carpal arch of the wrist is formed by irregularly shaped carpal bones interconnected by numerous ligaments, resulting in complex structural mechanics. The purpose of this study was to determine the three-dimensional stiffness characteristics of the carpal arch using displacement perturbations. It was hypothesized that the carpal arch would exhibit an anisotropic stiffness behavior with principal directions that are oblique to the conventional anatomical axes. Eight (n=8) cadavers were used in this study. For each specimen, the hamate was fixed to a custom stationary apparatus. An instrumented robot arm applied three-dimensional displacement perturbations to the ridge of trapezium and corresponding reaction forces were collected. The displacement-force data were used to determine a three-dimensional stiffness matrix using least squares fitting. Eigendecomposition of the stiffness matrix was used to identify the magnitudes and directions of the principal stiffness components. The carpal arch structure exhibited anisotropic stiffness behaviors with a maximum principal stiffness of 16.4±4.6N/mm that was significantly larger than the other principal components of 3.1±0.9 and 2.6±0.5N/mm (p<0.001). The principal direction of the maximum stiffness was pronated within the cross section of the carpal tunnel which is accounted for by the stiff transverse ligaments that tightly bind distal carpal arch. The minimal principal stiffness is attributed to the less constraining articulation between the trapezium and scaphoid. This study provides advanced characterization of the wrist׳s three-dimensional structural stiffness for improved insight into wrist biomechanics, stability, and function. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Thermal equilibrium of goats.

    PubMed

    Maia, Alex S C; Nascimento, Sheila T; Nascimento, Carolina C N; Gebremedhin, Kifle G

    2016-05-01

    The effects of air temperature and relative humidity on thermal equilibrium of goats in a tropical region was evaluated. Nine non-pregnant Anglo Nubian nanny goats were used in the study. An indirect calorimeter was designed and developed to measure oxygen consumption, carbon dioxide production, methane production and water vapour pressure of the air exhaled from goats. Physiological parameters: rectal temperature, skin temperature, hair-coat temperature, expired air temperature and respiratory rate and volume as well as environmental parameters: air temperature, relative humidity and mean radiant temperature were measured. The results show that respiratory and volume rates and latent heat loss did not change significantly for air temperature between 22 and 26°C. In this temperature range, metabolic heat was lost mainly by convection and long-wave radiation. For temperature greater than 30°C, the goats maintained thermal equilibrium mainly by evaporative heat loss. At the higher air temperature, the respiratory and ventilation rates as well as body temperatures were significantly elevated. It can be concluded that for Anglo Nubian goats, the upper limit of air temperature for comfort is around 26°C when the goats are protected from direct solar radiation.

  17. Motion planning and synchronized control of the dental arch generator of the tooth-arrangement robot.

    PubMed

    Jiang, Jin-Gang; Zhang, Yong-De

    2013-03-01

    The traditional, manual method of reproducing the dental arch form is prone to numerous random errors caused by human factors. The purpose of this study was to investigate the automatic acquisition of the dental arch and implement the motion planning and synchronized control of the dental arch generator of the multi-manipulator tooth-arrangement robot for use in full denture manufacture. First, the mathematical model of the dental arch generator was derived. Then the kinematics and control point position of the dental arch generator of the tooth arrangement robot were calculated and motion planning of each control point was analysed. A hardware control scheme is presented, based on the industrial personal computer and control card PC6401. In order to gain single-axis, precise control of the dental arch generator, we studied the control pulse realization of high-resolution timing. Real-time, closed-loop, synchronous control was applied to the dental arch generator. Experimental control of the dental arch generator and preliminary tooth arrangement were gained by using the multi-manipulator tooth-arrangement robotic system. The dental arch generator can automatically generate a dental arch to fit a patient according to the patient's arch parameters. Repeated positioning accuracy is 0.12 mm for the slipways that drive the dental arch generator. The maximum value of single-point error is 1.83 mm, while the arc-width direction (x axis) is -33.29 mm. A novel system that generates the dental arch has been developed. The traditional method of manually determining the dental arch may soon be replaced by a robot to assist in generating a more individual dental arch. The system can be used to fabricate full dentures and bend orthodontic wires. Copyright © 2012 John Wiley & Sons, Ltd.

  18. Lucy's Flat Feet: The Relationship between the Ankle and Rearfoot Arching in Early Hominins

    PubMed Central

    2010-01-01

    Background In the Plio-Pleistocene, the hominin foot evolved from a grasping appendage to a stiff, propulsive lever. Central to this transition was the development of the longitudinal arch, a structure that helps store elastic energy and stiffen the foot during bipedal locomotion. Direct evidence for arch evolution, however, has been somewhat elusive given the failure of soft-tissue to fossilize. Paleoanthropologists have relied on footprints and bony correlates of arch development, though little consensus has emerged as to when the arch evolved. Methodology/Principal Findings Here, we present evidence from radiographs of modern humans (n = 261) that the set of the distal tibia in the sagittal plane, henceforth referred to as the tibial arch angle, is related to rearfoot arching. Non-human primates have a posteriorly directed tibial arch angle, while most humans have an anteriorly directed tibial arch angle. Those humans with a posteriorly directed tibial arch angle (8%) have significantly lower talocalcaneal and talar declination angles, both measures of an asymptomatic flatfoot. Application of these results to the hominin fossil record reveals that a well developed rearfoot arch had evolved in Australopithecus afarensis. However, as in humans today, Australopithecus populations exhibited individual variation in foot morphology and arch development, and “Lucy” (A.L. 288-1), a 3.18 Myr-old female Australopithecus, likely possessed asymptomatic flat feet. Additional distal tibiae from the Plio-Pleistocene show variation in tibial arch angles, including two early Homo tibiae that also have slightly posteriorly directed tibial arch angles. Conclusions/Significance This study finds that the rearfoot arch was present in the genus Australopithecus. However, the female Australopithecus afarensis “Lucy” has an ankle morphology consistent with non-pathological flat-footedness. This study suggests that, as in humans today, there was variation in arch development

  19. Laboratory study of low-β forces in arched, line-tied magnetic flux ropes

    DOE PAGES

    Myers, C. E.; Yamada, M.; Ji, H.; ...

    2016-11-04

    Here, the loss-of-equilibrium is a solar eruption mechanism whereby a sudden breakdown of the magnetohydrodynamic force balance in the Sun's corona ejects a massive burst of particles and energy into the heliosphere. Predicting a loss-of-equilibrium, which has more recently been formulated as the torus instability, relies on a detailed understanding of the various forces that hold the pre-eruption magnetic flux rope in equilibrium. Traditionally, idealized analytical force expressions are used to derive simplified eruption criteria that can be compared to solar observations and modeling. What is missing, however, is a validation that these idealized analytical force expressions can be appliedmore » to the line-tied, low-aspect-ratio conditions of the corona. In this paper, we address this shortcoming by using a laboratory experiment to study the forces that act on long-lived, arched, line-tied magnetic flux ropes. Three key force terms are evaluated over a wide range of experimental conditions: (1) the upward hoop force; (2) the downward strapping force; and (3) the downward toroidal field tension force. First, the laboratory force measurements show that, on average, the three aforementioned force terms cancel to produce a balanced line-tied equilibrium. This finding validates the laboratory force measurement techniques developed here, which were recently used to identify a dynamic toroidal field tension force that can prevent flux rope eruption. The verification of magnetic force balance also confirms the low-beta assumption that the plasma thermal pressure is negligible in these experiments. Next, the measured force terms are directly compared to corresponding analytical expressions. While the measured and analytical forces are found to be well correlated, the low-aspect-ratio, line-tied conditions in the experiment are found to both reduce the measured hoop force and increase the measured tension force with respect to analytical expectations. These two co

  20. Laboratory study of low-β forces in arched, line-tied magnetic flux ropes

    NASA Astrophysics Data System (ADS)

    Myers, C. E.; Yamada, M.; Ji, H.; Yoo, J.; Jara-Almonte, J.; Fox, W.

    2016-11-01

    The loss-of-equilibrium is a solar eruption mechanism whereby a sudden breakdown of the magnetohydrodynamic force balance in the Sun's corona ejects a massive burst of particles and energy into the heliosphere. Predicting a loss-of-equilibrium, which has more recently been formulated as the torus instability, relies on a detailed understanding of the various forces that hold the pre-eruption magnetic flux rope in equilibrium. Traditionally, idealized analytical force expressions are used to derive simplified eruption criteria that can be compared to solar observations and modeling. What is missing, however, is a validation that these idealized analytical force expressions can be applied to the line-tied, low-aspect-ratio conditions of the corona. In this paper, we address this shortcoming by using a laboratory experiment to study the forces that act on long-lived, arched, line-tied magnetic flux ropes. Three key force terms are evaluated over a wide range of experimental conditions: (1) the upward hoop force; (2) the downward strapping force; and (3) the downward toroidal field tension force. First, the laboratory force measurements show that, on average, the three aforementioned force terms cancel to produce a balanced line-tied equilibrium. This finding validates the laboratory force measurement techniques developed here, which were recently used to identify a dynamic toroidal field tension force that can prevent flux rope eruptions [Myers et al., Nature 528, 526 (2015)]. The verification of magnetic force balance also confirms the low-β assumption that the plasma thermal pressure is negligible in these experiments. Next, the measured force terms are directly compared to corresponding analytical expressions. While the measured and analytical forces are found to be well correlated, the low-aspect-ratio, line-tied conditions in the experiment are found to both reduce the measured hoop force and increase the measured tension force with respect to analytical

  1. Sun's procedure for complex aortic arch repair: total arch replacement using a tetrafurcate graft with stented elephant trunk implantation.

    PubMed

    Ma, Wei-Guo; Zhu, Jun-Ming; Zheng, Jun; Liu, Yong-Min; Ziganshin, Bulat A; Elefteriades, John A; Sun, Li-Zhong

    2013-09-01

    The Sun's procedure is a surgical technique proposed by Dr. Li-Zhong Sun in 2002 that integrates total aortic arch replacement using a tetrafurcated graft with implantation of a specially designed frozen elephant trunk (Cronus(®)) in the descending aorta. It is used as a treatment option for extensive aortic dissections or aneurysms involving the ascending aorta, aortic arch and the descending aorta. The technical essentials of Sun's procedure include implantation of the special open stented graft into the descending aorta, total arch replacement with a 4-branched vascular graft, right axillary artery cannulation, selective antegrade cerebral perfusion for brain protection, moderate hypothermic circulatory arrest at 25 °C, a special anastomotic sequence for aortic reconstruction (i.e., proximal descending aorta → left carotid artery → ascending aorta → left subclavian artery → innominate artery), and early rewarming and reperfusion after distal anastomosis to minimize cerebral and cardiac ischemia. The core advantage of Sun's procedure lies in the use of a unique stented graft, which has superior technical simplicity, flexibility, inherent mechanical durability and an extra centimeter of attached regular vascular graft at both ends. Since its introduction in 2003, the Sun's procedure has produced satisfactory early and long-term results in over 8,000 patients in China and more than 200 patients in South American countries. In a series of 1,092 patients, the authors have achieved an in-hospital mortality rate of 6.27% (7.98% in emergent or urgent vs. 3.98% in elective cases). Given the accumulating clinical experience and the consequent, continual evolution of surgical indications, the Sun's procedure is becoming increasingly applied/used worldwide as an innovative and imaginative enhancement of surgical options for the dissected (or aneurysmal) ascending aorta, aortic arch and proximal descending aorta, and may become the next standard treatment for type

  2. Equilibrium of nematic vesicles

    NASA Astrophysics Data System (ADS)

    Napoli, Gaetano; Vergori, Luigi

    2010-11-01

    A variational scheme is proposed which allows the derivation of a concise and elegant formulation of the equilibrium equations for closed fluid membranes, endowed with a nematic microstructure. The nematic order is described by an in-plane nematic director and a degree of orientation, as customary in the theory of uniaxial nematics. The only constitutive ingredient in this scheme is a free-energy density which depends on the vesicle geometry and order parameters. The stress and the couple stress tensors related to this free-energy density are provided. As an application of the proposed scheme, a certain number of special theories are deduced: soap bubbles, lipid vesicles, chiral and achiral nematic membranes, and nematics on curved substrates.

  3. Statistical physics ""Beyond equilibrium

    SciTech Connect

    Ecke, Robert E

    2009-01-01

    The scientific challenges of the 21st century will increasingly involve competing interactions, geometric frustration, spatial and temporal intrinsic inhomogeneity, nanoscale structures, and interactions spanning many scales. We will focus on a broad class of emerging problems that will require new tools in non-equilibrium statistical physics and that will find application in new material functionality, in predicting complex spatial dynamics, and in understanding novel states of matter. Our work will encompass materials under extreme conditions involving elastic/plastic deformation, competing interactions, intrinsic inhomogeneity, frustration in condensed matter systems, scaling phenomena in disordered materials from glasses to granular matter, quantum chemistry applied to nano-scale materials, soft-matter materials, and spatio-temporal properties of both ordinary and complex fluids.

  4. Equilibrium Star Cluster Formation

    NASA Astrophysics Data System (ADS)

    Tan, Jonathan C.; Krumholz, Mark R.; McKee, Christopher F.

    2006-04-01

    We argue that rich star clusters take at least several local dynamical times to form and so are quasi-equilibrium structures during their assembly. Observations supporting this conclusion include morphologies of star-forming clumps, momentum flux of protostellar outflows from forming clusters, age spreads of stars in the Orion Nebula cluster (ONC) and other clusters, and the age of a dynamical ejection event from the ONC. We show that these long formation timescales are consistent with the expected star formation rate in turbulent gas, as recently evaluated by Krumholz & McKee. Finally, we discuss the implications of these timescales for star formation efficiencies, the disruption of gas by stellar feedback, mass segregation of stars, and the longevity of turbulence in molecular clumps.

  5. Arch length considerations due to the curve of Spee: a mathematical model.

    PubMed

    Germane, N; Staggers, J A; Rubenstein, L; Revere, J T

    1992-09-01

    Arch length analysis should consider discrepancies not only within the sagittal plane but also within the vertical and transverse planes. The vertical deviation of the occlusal plane from a flat plane is known as the curve of Spee. The purpose of this study was to produce a mathematical model of the mandibular arch form in three planes of space and to determine the effect that the curve of Spee has on arch circumference. Two mandibular arch forms, the catenary and the Bonwill-Hawley, were examined. The curve of Spee was modeled as a cylinder perpendicular to the midsagittal plane centered on the arch anteroposteriorly. A mathematical distance formula was used to calculate arch circumferences from the central fossa of the first molars for 10 arches with curves of Spee ranging from 0 to 10 mm. This procedure was repeated for arch circumferences extending from the central fossa of the second molars. Plots for the difference in arch circumferences verses depth of the curve of Spee showed that the relationship between these two variables is not linear and is less than one to one. This model showed that clinical practice of allowing 1 mm of arch circumference for leveling each millimeter of curve of Spee overestimates the amount of arch circumference needed to flatten the curve of Spee.

  6. An anatomical investigation of the superficial and deep palmar arches.

    PubMed

    Singh, Sadhna; Lazarus, Lelika; De Gama, Brenda Zola; Satyapal, Kapil Sewsaran

    2016-09-26

    The superficial and deep palmar arches provide the dominant vascular supply to the hand. The superficial palmar arch (SPA) is considered to be highly variable and can be classified as either complete or incomplete. The simplest definition states that the anastomosis between the vessels contributing to the arch represent a complete arch while an incomplete arch is described as having an absence of anastomosis between the vessels contributing to it. This study aimed to describe the anatomical landmarks, formation and branching patterns of the SPA and DPA. In this study, the SPA and deep palmar arch (DPA) were dissected in 50 specimens (n=100 adult hands), respectively. A complete SPA was observed in 92% of specimens and classified into three types. In Type A (44%), the SPA was formed by the anastomosis of the superficial palmar branch of the radial artery with the ulnar artery. Type B (46%) was formed by the ulnar artery alone and Type C (2%) was formed by anastomosis of the ulnar artery with the superficial palmar branch of the radial artery and the persistent median artery. An incomplete SPA was observed in 8% of the specimens and divided into three types formed by the radial and ulnar arteries. The DPA was divided into five types viz. Type G (72%), where the DPA was formed by anastomosis of the deep palmar branch of the radial artery (DPBRA) with the deep branch of the ulnar artery (DBUA). Type H (12%), was formed by anastomosis of the DPBRA, the DBUA and the interosseous artery. Type I (8%), was formed by the anastomosis of the DPBRA with the superior and inferior deep branch of the ulnar artery. Type J (4%), the deep ulnar artery had two branches whereby either one branch anastomosed with the DPBRA to form the DPA. Type K (4%), the DBUA exhibited two deep branches with one branch anastomosing with the DPBRA to complete the DPA. The interosseous artery anastomosed with either the DPA or the additional deep branch of the ulnar artery. Knowledge of the variability

  7. Mathematical definition of the shape of dental arches in human permanent healthy dentitions.

    PubMed

    Ferrario, V F; Sforza, C; Miani, A; Tartaglia, G

    1994-08-01

    Dental arch shape was studied in 50 men and 45 women aged 20-27 years with sound dentitions. Maxillary and mandibular arches were reconstructed by a fourth-order polynomial and a 'mixed' elliptical (anterior teeth), plus parabolic (post-canine teeth) interpolation of buccal cusp tips (central incisor to second molar). The maxillary arch resulted wider than the mandibular arch regardless of gender. Gender differences were found especially in the maxillary arch, where they reflect more a size discrepancy than a shape difference. The polynomial interpolation allowed the evaluation of arch asymmetry, which resulted negligible in all the subjects. The elliptical plus parabolic interpolation gave mean plots which were well superimposable to the ones obtained by the polynomial interpolation. These curves are geometrically simple and can be used for the mathematical description of dental arch shape in non-patient subjects. Moreover, they allow separate analysis of teeth with a different functional meaning.

  8. Butterfly arch: a device for precise controlling of the upper molars in three planes of space.

    PubMed

    Nikkerdar, Alireza

    2013-05-01

    Intra-oral appliances such as transpalatal arch and Nance appliance fail to resist against forces that tend to loosen the anchorage. The infirmity arises due to the long lever arm and the mesial force that is perpendicular to the long axis of the appliance. The butterfly arch is presented here as an intra-oral appliance that withstands the mesially directed forces with a mechanism that puts strain on a stiff wire along its long axis. The unique shape of the butterfly arch is advantageous in maximum anchorage cases, cases in which arch width preservation is critical and cases with a vertical growth pattern. With the aid of the butterfly arch, clinical concerns such as patient cooperation, wearing extra-oral appliances, complicated mechanics in extraction cases and control of the arch length, arch width and vertical dimension would be greatly diminished.

  9. Metric characterization of the aortic arch of early mouse fetuses and of a fetus featuring a double lumen aortic arch malformation.

    PubMed

    Geyer, Stefan H; Weninger, Wolfgang J

    2013-03-01

    This study aimed at providing an objective metric characterization of the aortic arch of a mouse fetus featuring a double lumen aortic arch malformation. As a side effect it provides reference data defining the length and the diameters of the aortic arch segments of normally developed mouse fetuses at developmental stage 22 according to Theiler (TS22). We analyzed a total of 22 TS22 mouse fetuses of the Him:OF1 strain. We produced high-resolution three-dimensional (3D) computer models and measured the diameters and cross sectional areas of the aortic arch segments and of the ascending and descending aorta. In addition, we defined 3D skeletons of the arteries and measured the length of the aortic arch segments. We provide statistics on the measurements obtained from the normally developed TS22 fetuses and detailed characterizations of the double lumen aortic arch. Our data suggest that: firstly, in Him:OF1 fetuses of TS22, the formation of the aortic arch is not yet finished. The left subclavian artery still receives a significant amount of blood from the right ventricle. Secondly, persistence of the 5th pharyngeal arch artery does not affect remodeling of the arteries distal to the junction of 5th pharyngeal arch artery and dorsal aorta. Thirdly, hemodynamic forces define the dimensions of the aortic arch between the left common carotid and the left subclavian artery. Fourthly, the blood volume streaming through the 4th pharyngeal arch artery influences its enlargement between TS20 and TS22. Copyright © 2012 Elsevier GmbH. All rights reserved.

  10. Equilibrium Policy Proposals with Abstentions.

    DTIC Science & Technology

    1981-05-01

    AB I I I EQUILIBRIUM POLICY PROPOSALS WITH ABSTENTIONS* by Peter Coughlin** 1. Introduction Spatial analyses of economic policy formation in elections...alternative in S at which there is a local equilibrium when the incumbent must defend the status quo. 5. Applications to Related Spatial Voting Models...York: Holt, Rinehart and Winston. Hestenes, M. [19751, Optimization Theoy, New York: Wiley. Hinich, M. [1977], " Equilibrium in Spatial Voting: The Median

  11. Grinding kinetics and equilibrium states

    NASA Technical Reports Server (NTRS)

    Opoczky, L.; Farnady, F.

    1984-01-01

    The temporary and permanent equilibrium occurring during the initial stage of cement grinding does not indicate the end of comminution, but rather an increased energy consumption during grinding. The constant dynamic equilibrium occurs after a long grinding period indicating the end of comminution for a given particle size. Grinding equilibrium curves can be constructed to show the stages of comminution and agglomeration for certain particle sizes.

  12. The Nash equilibrium: A perspective

    PubMed Central

    Holt, Charles A.; Roth, Alvin E.

    2004-01-01

    In 1950, John Nash contributed a remarkable one-page PNAS article that defined and characterized a notion of equilibrium for n- person games. This notion, now called the “Nash equilibrium,” has been widely applied and adapted in economics and other behavioral sciences. Indeed, game theory, with the Nash equilibrium as its centerpiece, is becoming the most prominent unifying theory of social science. In this perspective, we summarize the historical context and subsequent impact of Nash's contribution. PMID:15024100

  13. Computational Study of Growth and Remodeling in the Aortic Arch

    PubMed Central

    Alford, Patrick W.; Taber, Larry A.

    2009-01-01

    Opening angles (OAs) are associated with growth and remodeling in arteries. One curiosity has been the relatively large OAs found in the aortic arch of some animals. Here, we use computational models to explore the reasons behind this phenomenon. The artery is assumed to contain a smooth muscle/collagen phase and an elastin phase. In the models, growth and remodeling of smooth muscle/collagen depends on wall stress and fluid shear stress. Remodeling of elastin, which normally turns over very slowly, is neglected. The results indicate that OAs generally increase with longitudinal curvature (torus model), earlier elastin production during development, and decreased wall stiffness. Correlating these results with available experimental data suggests that all of these effects may contribute to the large OAs in the aortic arch. The models also suggest that the slow turnover rate of elastin limits longitudinal growth. These results should promote increased understanding of the causes of residual stress in arteries. PMID:18792831

  14. Left cervical aortic arch: diagnosis by radioisotope and ultrasound techniques

    SciTech Connect

    Camiel, M.R.; Glanz, S.; Gordon, D.H.; Weiner, R.

    1982-01-01

    Two case histories are presented of patients with a developmental variant of the heart. The condition is usually innocuous but its appearance is confusing and incorrect diagnoses are possible. Although the abnormality is usually first detected by routine chest X-ray, radionuclide angiography and sonography are more appropriate diagnostic measures. The two methods can differentiate between the cervical aortic arch and aneurysm or lung tumor. (JMT)

  15. Gonococcal ascending aortic aneurysm with penetrating ulcer and bovine arch.

    PubMed

    Oumeiri, Bachar El; Eynden, Frédéric Vanden; Stefanidis, Constantin; Antoine, Martine; Nooten, Guido Van

    2015-09-01

    We describe a patient with ascending aorta aneurysm and bovine aortic arch who initially presented with fever. A 65-year-old man with a 2-month history of intermittent fever was referred to our hospital and diagnosed as having a gonococcal ascending aorta aneurysm with penetrating ulcers. He was successfully treated by resection of the ascending aorta and ulcers, replacement of the aortic valve, and prolonged postoperative antibiotic therapy.

  16. Complex Atheromatosis of the Aortic Arch in Cerebral Infarction

    PubMed Central

    Capmany, Ramón Pujadas; Ibañez, Montserrat Oliveras; Pesquer, Xavier Jané

    2010-01-01

    In many stroke patients it is not possible to establish the etiology of stroke. However, in the last two decades, the use of transesophageal echocardiography in patients with stroke of uncertain etiology reveals atherosclerotic plaques in the aortic arch, which often protrude into the lumen and have mobile components in a high percentage of cases. Several autopsy series and retrospective studies of cases and controls have shown an association between aortic arch atheroma and arterial embolism, which was later confirmed by prospectively designed studies. The association with ischemic stroke was particularly strong when atheromas were located proximal to the ostium of the left subclavian artery, when the plaque was ≥ 4 mm thick and particularly when mobile components are present. In these cases, aspirin might not prevent adequately new arterial ischemic events especially stroke. Here we review the evidence of aortic arch atheroma as an independent risk factor for stroke and arterial embolism, including clinical and pathological data on atherosclerosis of the thoracic aorta as an embolic source. In addition, the impact of complex plaques (≥ 4 mm thick, or with mobile components) on increasing the risk of stroke is also reviewed. In non-randomized retrospective studies anticoagulation was superior to antiplatelet therapy in patients with stroke and aortic arch plaques with mobile components. In a retrospective case-control study, statins significantly reduced the relative risk of new vascular events. However, given the limited data available and its retrospective nature, randomized prospective studies are needed to establish the optimal secondary prevention therapeutic regimens in these high risk patients. PMID:21804777

  17. Gunshot Injury to the Anterior Arch of Atlas

    PubMed Central

    Park, Jun Hee; Kim, Hyeung Sun; Do, Nam Yong

    2012-01-01

    Penetrating injuries to the upper cervical spine resulting from gunshots are rare in South Korea due to restrictions of gun use. Moreover, gunshot wounds to the upper cervical spine without neurological deficits occur infrequently because of the anatomic location and surrounding essential structures. We present an uncommon case involving the surgical removal of a bullet located in the anterior arch of first cervical vertebra (C1) via a transoral approach without neurological complications or subsequent mechanical instability. PMID:22639715

  18. Controlled localized buckling responses of orthodontic arch wires.

    PubMed

    Nikolai, R J; Chung, A Y

    1999-09-01

    The orthodontic arch wire is often activated locally, in transverse bending and/or longitudinal torsion, to engage an individual malaligned tooth. Arch wires with substantial flexibilities and elastic ranges in bending are available. Several clinical reports of distal displacements of molars with appliances activated by locally buckling the arch wire have appeared in the recent published literature. This article contains an explanation of buckling or "column" action and the postbuckling response of a wire, and a report of the results of a controlled, in-vitro study of a sample of 256 wire segments subjected to activation-deactivation, buckling-postbuckling-unbuckling cycles. Continuous force-displacement diagrams were obtained from mechanical tests run at oral temperature. Four orthodontics-relevant, mechanical characteristics were quantified from each diagram, and each specimen was subjected to posttest evaluation for inelastic behavior. Although the deformation of the buckled wire is, in fact, bending, the force-displacement diagrams obtained differed substantially from their familiar counterparts generated in transverse bending. Judging from the force magnitudes induced as the deactivation half-cycles commenced as well as the deactivation rates, not all of the 8 wires seem to be clinically suitable for activation initiated by buckling. Magnitudes of springback were substantial from activations as large as 6 mm, and only 2 of the 8 wires exhibited full deactivations less than 80% of their activating displacements. This relatively new mode of arch wire activation that enables delivery to the dentition of mesiodistal pushing forces has substantial potential for clinical application from several biomechanical standpoints.

  19. Double arch mirror study. Part 3: Fabrication and test report

    NASA Technical Reports Server (NTRS)

    Vukobratovich, D.; Hillman, D.

    1983-01-01

    A method of mounting a cryogenically cooled, lightweight, double arch, glass mirror was developed for infrared, astronomical telescopes such as the Space Infrared Telescope Facility (SIRTF). A 50 cm, fused silica mirror which was previously fabricated was modified for use with a new mount configuration. This mount concept was developed. The modification of the mirror, the fabrication of the mirror mount, and the room temperature testing of the mounted mirror are reported. A design for a SIRTF class primary mirror is suggested.

  20. [Tuberculosis of the posterior vertebral arch. A case report].

    PubMed

    Nassar, I; Mahi, M; Semlali, S; Kacemi, L; El Quessar, A; Chakir, N; El Hassani, M R; Jiddane, M

    2002-09-01

    Tuberculosis of the spine usually involves the vertebral body and intervertebral disk. Involvement of the posterior arch is rare. We report a case of tuberculosis involving the posterior elements of the T4 and T5 vertebrae in a 38 year old woman. CT is helpful to assess bony structures whereas MRI is ideal to evaluate the neural structures. Clinical, radiographic, and therapeutic considerations regarding tuberculosis of the spine are reviewed.

  1. Ontogeny of bone strain: the zygomatic arch in pigs

    PubMed Central

    Pedersen, Scott C.; Huang, Xiaofeng

    2006-01-01

    Summary At the time of weaning, infant animals have little experience with hard food, and thus their skulls are not likely to be epigenetically adapted for the loads imposed by mastication. We examined bone strain in the zygomatic arch of 4-week-old weanling piglets. Functional strains in piglets differed from those previously reported for older pigs (Herring et al., 1996; Rafferty et al., 2000) in that the squamosal bone was not bent in the horizontal plane and the principal tensile strain on the zygomatic bone did not correspond to the direction of masseter muscle pull. Strain patterns were more variable in piglets than in older pigs. In older pigs masticatory strains can be reproduced by stimulating the masseter muscles. When the piglet masseter was stimulated, strain patterns were more similar to those of older pigs, but shear strain magnitudes were the largest yet recorded from mammalian skull bones, up to 4000 με. To put these findings in the context of skeletal adaptation, 45 dry skulls, including some animals from the strain study, were measured. Reduced major axis regressions indicated that the infant arch was rounder in cross section and straighter than that of older animals. With growth the arch became dorsoventrally higher, while mediolateral thickness decreased in the squamosal bone. Overall, these changes should make strain more predictable, explaining the lower variability in older animals. Other factors likely to be important in causing unique strain regimes in piglets include (1) unfamiliarity with hard food, (2) greater importance of muscles other than the same-side masseter, and (3) greater proximity of molariform teeth to the arch. Collectively, these data indicate that the skeleton is not pre-adapted for specific functional loads. PMID:16339870

  2. Hemiarthroplasty for proximal humeral fracture: restoration of the Gothic arch.

    PubMed

    Krishnan, Sumant G; Bennion, Phillip W; Reineck, John R; Burkhead, Wayne Z

    2008-10-01

    Proximal humerus fractures are the most common fractures of the shoulder girdle, and initial management of these injuries often determines final outcome. When arthroplasty is used to manage proximal humeral fractures, surgery remains technically demanding, and outcomes have been unpredictable. Recent advances in both technique and prosthetic implants have led to more successful and reproducible results. Key technical points include restoration of the Gothic arch, anatomic tuberosity reconstruction, and minimal soft tissue dissection.

  3. Metallicity in the Galactic Center: The Arches Cluster

    NASA Astrophysics Data System (ADS)

    Najarro, Francisco; Figer, Donald F.; Hillier, D. John; Kudritzki, Rolf P.

    2004-04-01

    We present a quantitative spectral analysis of five very massive stars in the Arches cluster, located near the Galactic center, to determine stellar parameters, stellar wind properties, and, most importantly, metallicity content. The analysis uses a new technique, presented here for the first time, and uses line-blanketed non-LTE wind/atmosphere models fitted to high-resolution near-infrared spectra of late-type nitrogen-rich Wolf-Rayet stars and OfI+ stars in the cluster. It relies on the fact that massive stars reach a maximum nitrogen abundance that is related to initial metallicity when they are in the WNL phase. We determine the present-day nitrogen abundance of the WNL stars in the Arches cluster to be 1.6% (mass fraction) and constrain the stellar metallicity in the cluster to be solar. This result is invariant to assumptions about the mass-luminosity relationship, the mass-loss rates, and rotation speeds. In addition, from this analysis, we find the age of the Arches cluster to be 2-2.5 Myr, assuming coeval formation.

  4. Rapidly growing aortic arch aneurysm in Behcet's disease.

    PubMed

    Kojima, Nozomi; Sakano, Yasuhito; Ohki, Shin-Ichi; Misawa, Yoshio

    2011-03-01

    We present a patient with a nine-year history of Behçet's disease (BD), who developed a rapidly expanding aneurysm of the aortic arch. Three-dimensional computed tomography demonstrated a saccular aortic arch aneurysm with a maximal diameter of 5 cm. No bacteria were detected by serial blood cultures. The aneurysm, however, showed a multi-lobular cavity, mimicking an infectious aneurysm. Therefore, we prescribed antibacterial agents for one week. The patient still had a high-fever and an elevated C-reactive protein level thereafter. Aortic arch replacement was performed emergently. Because we were unable to determine whether the aneurysm was caused by infection or BD, the implanted prosthetic graft and the anastomotic sites were covered with a pedicle graft of the greater omentum, and we continued to administer antibacterial agents for four weeks postoperatively. The pathological examination showed neither bacteria nor cystic medial necrosis in the resected aortic wall. Inflammatory changes with eosinophilic infiltration were recognized mainly around the adventitia near the aneurysm. The patient had a favorable postoperative course without any complications.

  5. Biomechanics of the transverse carpal arch under carpal bone loading.

    PubMed

    Xiu, Kai-Hua; Kim, Joo-Han; Li, Zong-Ming

    2010-10-01

    Carpal tunnel release and conservative interventions are widely used in clinical therapies of carpal tunnel syndrome. The efficacy of these treatment and interventions mainly lies in the exploitation of the mechanical properties of carpal tunnel. This study investigated the structural mechanics of the transverse carpal arch using cadaveric hands. Paired force was applied to the insertion sites of the transverse carpal ligament at both the distal (hamate-trapezium) and proximal (pisiform-scaphoid) levels of the carpal tunnel. The two pairs of forces were simultaneously applied in an inward or outward direction when the transverse carpal ligament was intact and transected. Transverse carpal arch and carpal tunnel compliance in response to the forces were analyzed. Three-way repeated measures ANOVA were used to examine the effect of the transverse carpal ligament status (intact/transected), the level of the carpal tunnel (distal/proximal) and the force application direction (inward/outward) on the biomechanics of the transverse carpal arch. Transverse carpal ligament plays a stabilizing role in resisting outward deformation of the carpal tunnel. The carpal tunnel at the proximal level is more flexible than the carpal tunnel at the distal level. The carpal tunnel is more compliant under the inward force application than under the outward force application. The understanding of carpal tunnel mechanics potentially helps to improve the existing strategies and to develop alternatives for the treatment of carpal tunnel syndrome. 2010 Elsevier Ltd. All rights reserved.

  6. Biomechanics of the Transverse Carpal Arch under Carpal Bone Loading

    PubMed Central

    Xiu, Kai-Hua; Kim, Joo-Han; Li, Zong-Ming

    2010-01-01

    Background Carpal tunnel release and conservative interventions are widely used in clinical therapies of carpal tunnel syndrome. The efficacy of these treatment and interventions mainly lies in the exploitation of the mechanical properties of carpal tunnel. This study investigated the structural mechanics of the transverse carpal arch using cadaveric hands. Methods Paired force was applied to the insertion sites of the transverse carpal ligament at both the distal (hamate -trapezium) and proximal (pisiform - scaphoid) level of the carpal tunnel. The two pairs of forces were simultaneously applied in an inward or outward direction when the transverse carpal ligament was intact and transected. Transverse carpal arch and carpal tunnel compliance in response to the forces were analyzed. Three-way repeated measures ANOVA were used to examine the effect of the transverse carpal ligament status (intact/transected), the level of the carpal tunnel (distal/proximal) and the force application direction (inward/outward) on the biomechanics of the transverse carpal arch. Findings Transverse carpal ligament plays a stabilizing role in resisting outward deformation of the carpal tunnel. The carpal tunnel at the proximal level is more flexible than the carpal tunnel at the distal level. The carpal tunnel is more compliant under the inward force application than under the outward force application. Interpretation The understanding of carpal tunnel mechanics potentially helps to improve the existing strategies and to develop alternatives for the treatment of carpal tunnel syndrome. PMID:20579787

  7. Surface characterization of nickel titanium orthodontic arch wires

    PubMed Central

    Krishnan, Manu; Seema, Saraswathy; Tiwari, Brijesh; Sharma, Himanshu S.; Londhe, Sanjay; Arora, Vimal

    2015-01-01

    Background Surface roughness of nickel titanium orthodontic arch wires poses several clinical challenges. Surface modification with aesthetic/metallic/non metallic materials is therefore a recent innovation, with clinical efficacy yet to be comprehensively evaluated. Methods One conventional and five types of surface modified nickel titanium arch wires were surface characterized with scanning electron microscopy, energy dispersive analysis, Raman spectroscopy, Atomic force microscopy and 3D profilometry. Root mean square roughness values were analyzed by one way analysis of variance and post hoc Duncan's multiple range tests. Results Study groups demonstrated considerable reduction in roughness values from conventional in a material specific pattern: Group I; conventional (578.56 nm) > Group V; Teflon (365.33 nm) > Group III; nitride (301.51 nm) > Group VI (i); rhodium (290.64 nm) > Group VI (ii); silver (252.22 nm) > Group IV; titanium (229.51 nm) > Group II; resin (158.60 nm). It also showed the defects with aesthetic (resin/Teflon) and nitride surfaces and smooth topography achieved with metals; titanium/silver/rhodium. Conclusions Resin, Teflon, titanium, silver, rhodium and nitrides were effective in decreasing surface roughness of nickel titanium arch wires albeit; certain flaws. Findings have clinical implications, considering their potential in lessening biofilm adhesion, reducing friction, improving corrosion resistance and preventing nickel leach and allergic reactions. PMID:26843749

  8. Disentangling the Free-Fall Arch Paradox in Silo Discharge.

    PubMed

    Rubio-Largo, S M; Janda, A; Maza, D; Zuriguel, I; Hidalgo, R C

    2015-06-12

    Several theoretical predictions of the mass flow rate of granular media discharged from a silo are based on the spontaneous development of a free-fall arch region, the existence of which is still controversial. In this Letter, we study experimentally and numerically the particle flow through an orifice placed at the bottom of 2D and 3D silos. The implementation of a coarse-grained technique allows a thorough description of all the kinetic and micromechanical properties of the particle flow in the outlet proximities. Though the free-fall arch does not exist as traditionally understood--a region above which particles have negligible velocity and below which particles fall solely under gravity action--we discover that the kinetic pressure displays a well-defined transition in a position that scales with the outlet size. This universal scaling explains why the free-fall arch picture has served as an approximation to describe the flow rate in the discharge of silos.

  9. Convective quasi-equilibrium

    NASA Astrophysics Data System (ADS)

    Yano, J.-I.; Plant, R. S.

    2012-12-01

    The concept of convective quasi-equilibrium (CQE) is a key ingredient in order to understand the role of deep moist convection in the atmosphere. It has been used as a guiding principle to develop almost all convective parameterizations and provides a basic theoretical framework for large-scale tropical dynamics. The CQE concept as originally proposed by Arakawa and Schubert (1974) is systematically reviewed from wider perspectives. Various interpretations and extensions of Arakawa and Schubert's CQE are considered both in terms of a thermodynamic analogy and as a dynamical balance. The thermodynamic interpretations can be more emphatically embraced as a homeostasis. The dynamic balance interpretations can be best understood by analogy with the slow manifold. Various criticisms of CQE can be avoided by taking the dynamic balance interpretation. Possible limits of CQE are also discussed, including the importance of triggering in many convective situations, as well as the possible self-organized criticality of tropical convection. However, the most intriguing aspect of the CQE concept is that in spite of many observational tests supporting and interpreting it in many different senses, it has never been established in a robust manner based on a systematic analysis of the cloud work function budget by observations as was originally defined.

  10. Napoleon Is in Equilibrium

    NASA Astrophysics Data System (ADS)

    Phillips, Rob

    2015-03-01

    It has been said that the cell is the test tube of the twenty-first century. If so, the theoretical tools needed to quantitatively and predictively describe what goes on in such test tubes lag sorely behind the stunning experimental advances in biology seen in the decades since the molecular biology revolution began. Perhaps surprisingly, one of the theoretical tools that has been used with great success on problems ranging from how cells communicate with their environment and each other to the nature of the organization of proteins and lipids within the cell membrane is statistical mechanics. A knee-jerk reaction to the use of statistical mechanics in the description of cellular processes is that living organisms are so far from equilibrium that one has no business even thinking about it. But such reactions are probably too hasty given that there are many regimes in which, because of a separation of timescales, for example, such an approach can be a useful first step. In this article, we explore the power of statistical mechanical thinking in the biological setting, with special emphasis on cell signaling and regulation. We show how such models are used to make predictions and describe some recent experiments designed to test them. We also consider the limits of such models based on the relative timescales of the processes of interest.

  11. Napoleon Is in Equilibrium.

    PubMed

    Phillips, Rob

    2015-03-01

    It has been said that the cell is the test tube of the twenty-first century. If so, the theoretical tools needed to quantitatively and predictively describe what goes on in such test tubes lag sorely behind the stunning experimental advances in biology seen in the decades since the molecular biology revolution began. Perhaps surprisingly, one of the theoretical tools that has been used with great success on problems ranging from how cells communicate with their environment and each other to the nature of the organization of proteins and lipids within the cell membrane is statistical mechanics. A knee-jerk reaction to the use of statistical mechanics in the description of cellular processes is that living organisms are so far from equilibrium that one has no business even thinking about it. But such reactions are probably too hasty given that there are many regimes in which, because of a separation of timescales, for example, such an approach can be a useful first step. In this article, we explore the power of statistical mechanical thinking in the biological setting, with special emphasis on cell signaling and regulation. We show how such models are used to make predictions and describe some recent experiments designed to test them. We also consider the limits of such models based on the relative timescales of the processes of interest.

  12. Mid-Term Outcomes of a Modification of Extended Aortic Arch Anastomosis with Pulmonary Artery Banding in Single Ventricle Neonates with Hypoplastic Transverse Arch

    PubMed Central

    Thang, Bui Quoc; Furugaki, Tatsuya; Osaka, Motoo; Watanabe, Yutaka; Kanemoto, Shinya; Suetsugu, Fuminaga

    2016-01-01

    Purpose: There is less certainty regarding the best strategy for treating neonates with functional single ventricle (SV) and hypoplastic aortic arch. We have applied a modified extended aortic arch anastomosis (EAAA) and main pulmonary artery banding (PAB) as an initial palliation in neonates with transverse arch hypoplasia and assessed the mid-term outcomes. Methods: In total, 10 neonates with functional SV and extensive hypoplasia or interruption of the arch underwent a modified EAAA (extended arch anastomosis with a subclavian flap) concomitant with main PAB through a thoracotomy without cardiopulmonary bypass. Patient age and weight ranged from 4 to 14 days and 2.3 to 3.8 kg, respectively. Results: There were no hospital deaths although there were two late deaths. Gradients across the arch were 0 to 7 mmHg at postoperative day 1 and no arch reoperations were required. Two patients required balloon aortoplasty. Nine underwent bidirectional cavopulmonary shunt and two of them needed concomitant Damus–Kaye–Stansel (DKS) anastomosis. Six have completed Fontan. Conclusion: Our modification of EAAA with main PAB for SV neonates may benefit a certain population with transverse arch hypoplasia as an option to be considered. Patients with the potential for developing outflow obstruction may be best managed with an initial DKS-type palliation. PMID:27725352

  13. The effect of foot arch on plantar pressure distribution during standing.

    PubMed

    Periyasamy, R; Anand, Sneh

    2013-07-01

    The aim of this study was to explore how foot type affects plantar pressure distribution during standing. In this study, 32 healthy subjects voluntarily participated and the subject feet were classified as: normal feet (n = 23), flat feet (n = 14) and high arch feet (n = 27) according to arch index (AI) values obtained from foot pressure intensity image analysis. Foot pressure intensity images were acquired by a pedopowergraph system to obtain a foot pressure distribution parameter-power ratio (PR) during standing in eight different regions of the foot. Contact area and mean PR were analysed in hind foot, mid-foot and fore foot regions. One-way analysis of variance was used to determine statistical differences between groups. The contact area and mean PR value beneath the mid-foot was significantly increased in the low arch foot when compared to the normal arch foot and high arch foot (p < 0.001) in both feet. However, subjects with low-arch feet had significantly higher body mass index (BMI) compared to subjects with high-arch feet (p < 0.05) and subjects with normal arch feet (p < 0.05) in both feet. In addition, subjects with low-arch feet had significant differences in arch index (AI) value as compared to subjects with high-arch feet (p < 0.001) and subjects with normal arch feet (p < 0.05) in both feet. Mean mid-foot PR value were positively (r = 0.54) correlated with increased arch index (AI) value. A significant (p < 0.05) change was obtained in PR value beneath the mid-foot of low arch feet when compared with other groups in both feet. The findings suggest that there is an increased mid-foot PR value in the low arch foot as compared to the normal arch foot and high arch foot during standing. Therefore, individuals with low arch feet could be at high risk for mid-foot collapse and Charcot foot problems, indicating that foot type should be assessed when determining an individual's risk for foot injury.

  14. The Foot’s Arch and the Energetics of Human Locomotion

    PubMed Central

    Stearne, Sarah M.; McDonald, Kirsty A.; Alderson, Jacqueline A.; North, Ian; Oxnard, Charles E.; Rubenson, Jonas

    2016-01-01

    The energy-sparing spring theory of the foot’s arch has become central to interpretations of the foot’s mechanical function and evolution. Using a novel insole technique that restricted compression of the foot’s longitudinal arch, this study provides the first direct evidence that arch compression/recoil during locomotion contributes to lowering energy cost. Restricting arch compression near maximally (~80%) during moderate-speed (2.7 ms−1) level running increased metabolic cost by + 6.0% (p < 0.001, d = 0.67; unaffected by foot strike technique). A simple model shows that the metabolic energy saved by the arch is largely explained by the passive-elastic work it supplies that would otherwise be done by active muscle. Both experimental and model data confirm that it is the end-range of arch compression that dictates the energy-saving role of the arch. Restricting arch compression had no effect on the cost of walking or incline running (3°), commensurate with the smaller role of passive-elastic mechanics in these gaits. These findings substantiate the elastic energy-saving role of the longitudinal arch during running, and suggest that arch supports used in some footwear and orthotics may increase the cost of running. PMID:26783259

  15. ARCHES: Advancing Research & Capacity in Hydrologic Education and Science

    NASA Astrophysics Data System (ADS)

    Milewski, A.; Fryar, A. E.; Durham, M. C.; Schroeder, P.; Agouridis, C.; Hanley, C.; Rotz, R. R.

    2013-12-01

    Educating young scientists and building capacity on a global scale is pivotal towards better understanding and managing our water resources. Based on this premise the ARCHES (Advancing Research & Capacity in Hydrologic Education and Science) program has been established. This abstract provides an overview of the program, links to access information, and describes the activities and outcomes of student participants from the Middle East and North Africa. The ARCHES program (http://arches.wrrs.uga.edu) is an integrated hydrologic education approach using online courses, field programs, and various hands-on workshops. The program aims to enable young scientists to effectively perform the high level research that will ultimately improve quality of life, enhance science-based decision making, and facilitate collaboration. Three broad, interlinked sets of activities are incorporated into the ARCHES program: (A1) the development of technical expertise, (A2) the development of professional contacts and skills, and (A3) outreach and long-term sustainability. The development of technical expertise (A1) is implemented through three progressive instructional sections. Section 1: Students were guided through a series of online lectures and exercises (Moodle: http://wrrs.uga.edu/moodle) covering three main topics (Remote Sensing, GIS, and Hydrologic Modeling). Section 2: Students participated in a hands-on workshop hosted at the University of Georgia's Water Resources and Remote Sensing Laboratory (WRRSL). Using ENVI, ArcGIS, and ArcSWAT, students completed a series of lectures and real-world applications (e.g., Development of Hydrologic Models). Section 3: Students participated in field studies (e.g., measurements of infiltration, recharge, streamflow, and water-quality parameters) conducted by U.S. partners and international collaborators in the participating countries. The development of professional contacts and skills (A2) was achieved through the promotion of networking

  16. Laboratory simulation of magnetic plasma arch eruptions on the Sun

    NASA Astrophysics Data System (ADS)

    Tripathi, Shreekrishna; Gekelman, W.

    2013-07-01

    Eruption of arched magnetoplasma structures is a fundamental process that drives solar energetic events on wide spatiotemporal scales in the solar atmosphere. The term arched magnetic flux rope (AMFR) is associated with such structures since they carry electrical current which generates a twisted magnetic structure. In the limit of a low electrical-current, the magnetic-field-line-twist becomes small and a magnetic flux rope resembles the structure of a magnetic flux tube. A laboratory plasma experiment has been constructed at UCLA which is capable of generating reproducible AMFR eruptions with a 0.5 Hz repetition rate and recording their spatiotemporal evolution using computer-controlled movable probes (n ~ 1013 cm-3, Te ~ 10 eV, L = 0.5 m, I = 100 A, B ~ 1 kG at footpoints). The experiment has been designed by careful scaling of the relevant solar plasma parameters and the boundary conditions can be controlled to simulate a variety of drive mechanisms that may exist on the Sun (e.g., mass flow vs current flow from the AMFR footpoints, slow vs fast buildup of the magnetic energy in the arch). The AMFR evolves in a large background magnetoplasma (n ~ 1012 cm-3, Te ~ 4 eV, B = 20-100 G). The relative magnitudes of the plasma parameters of the AMFR and the ambient magnetoplasma can be varied. Stereo images of the AMFR evolution are recorded by a fast CCD camera using a variety of pass-band filters. In this presentation, recent experimental results comparing a fast eruption (time scale t < 3. Alfven transit time in the arch) with a slow eruption (time scale t > 100. Alfven transit time in the arch) of the AMFR will be discussed. The highlights of the post-eruption AMFR are low frequency global kink mode oscillations (f ~ 200 kHz) that appear concurrently with high-frequency fast waves (f ~ 5 MHz) in the AMFR. References: (1) S. K. P. Tripathi and W. Gekelman, Phys. Rev. Lett. 105, 075005 (2010) (2) S. K. P. Tripathi and W. Gekelman, Solar Physics, Published online 8

  17. Thermodynamic efficiency out of equilibrium

    NASA Astrophysics Data System (ADS)

    Sivak, David; Crooks, Gavin

    2011-03-01

    Molecular-scale machines typically operate far from thermodynamic equilibrium, limiting the applicability of equilibrium statistical mechanics to understand their efficiency. Thermodynamic length analysis relates a non-equilibrium property (dissipation) to equilibrium properties (equilibrium fluctuations and their relaxation time). Herein we demonstrate that the thermodynamic length framework follows directly from the assumptions of linear response theory. Uniting these two frameworks provides thermodynamic length analysis a firmer statistical mechanical grounding, and equips linear response theory with a metric structure to facilitate the prediction and discovery of optimal (minimum dissipation) paths in complicated free energy landscapes. To explore the applicability of this theoretical framework, we examine its accuracy for simple bistable systems, parametrized to model single-molecule force-extension experiments. Through analytic derivation of the equilibrium fluctuations and numerical calculation of the dissipation and relaxation time, we verify that thermodynamic length analysis (though derived in a near-equilibrium limit) provides a strikingly good approximation even far from equilibrium, and thus provides a useful framework for understanding molecular motor efficiency.

  18. Equilibrium states for hyperbolic potentials

    NASA Astrophysics Data System (ADS)

    Ramos, Vanessa; Viana, Marcelo

    2017-02-01

    We prove the existence of finitely many ergodic equilibrium states for local homeomorphisms and hyperbolic potentials. We also deal with partially hyperbolic skew-products over non-uniformly expanding maps with uniform contraction on the fibre. For these systems we prove the existence and finiteness of the equilibrium states associated with a class of Hölder continuous potentials.

  19. Rapid-Equilibrium Enzyme Kinetics

    ERIC Educational Resources Information Center

    Alberty, Robert A.

    2008-01-01

    Rapid-equilibrium rate equations for enzyme-catalyzed reactions are especially useful because if experimental data can be fit by these simpler rate equations, the Michaelis constants can be interpreted as equilibrium constants. However, for some reactions it is necessary to use the more complicated steady-state rate equations. Thermodynamics is…

  20. [Oculomotor equilibrium and aviation activities].

    PubMed

    Maille, M; Pedeprat Lamechinou, P; Corbe, C; Manent, P J

    1989-01-01

    A good oculomotor equilibrium warrants flight safety. It is indeed directly linked with depth vision an may decompensate, causing a deficit or a diplopia. It is therefore very important to screen pilots carefully and to have periodical examinations to check the oculomotor equilibrium.

  1. Rapid-Equilibrium Enzyme Kinetics

    ERIC Educational Resources Information Center

    Alberty, Robert A.

    2008-01-01

    Rapid-equilibrium rate equations for enzyme-catalyzed reactions are especially useful because if experimental data can be fit by these simpler rate equations, the Michaelis constants can be interpreted as equilibrium constants. However, for some reactions it is necessary to use the more complicated steady-state rate equations. Thermodynamics is…

  2. Total arch repair for acute type A aortic dissection with open placement of a modified triple-branched stent graft and the arch open technique

    PubMed Central

    2014-01-01

    Background In total arch repair with open placement of a triple-branched stent graft for acute type A aortic dissection, the diameters of the native arch vessels and the distances between 2 neighboring arch vessels did not always match the available sizes of the triple-branched stent grafts, and insertion of the triple-branched stent graft through the distal ascending aortic incision was not easy in some cases. To reduce those two problems, we modified the triple-branched stent graft and developed the arch open technique. Methods and results Total arch repair with open placement of a modified triple-branched stent graft and the arch open technique was performed in 25 consecutive patients with acute type A aortic dissection. There was 1 surgical death. Most survivors had an uneventful postoperative course. All implanted stents were in a good position and wide expansion, there was no space or blood flow surrounding the stent graft. Complete thrombus obliteration of the false lumen was found around the modified triple-branched stent graft in all survivors and at the diaphragmatic level in 20 of 24 patients. Conclusions The modified triple-branched stent graft could provide a good match with the different diameters of the native arch vessels and the various distances between 2 neighboring arch vessels, and it’s placement could become much easier by the arch open technique. Consequently, placement of a modified triple-branched stent graft could be easily used in most patients with acute type A aortic dissection for effective total arch repair. PMID:25085259

  3. Equilibrium Shape of Colloidal Crystals.

    PubMed

    Sehgal, Ray M; Maroudas, Dimitrios

    2015-10-27

    Assembling colloidal particles into highly ordered configurations, such as photonic crystals, has significant potential for enabling a broad range of new technologies. Facilitating the nucleation of colloidal crystals and developing successful crystal growth strategies require a fundamental understanding of the equilibrium structure and morphology of small colloidal assemblies. Here, we report the results of a novel computational approach to determine the equilibrium shape of assemblies of colloidal particles that interact via an experimentally validated pair potential. While the well-known Wulff construction can accurately capture the equilibrium shape of large colloidal assemblies, containing O(10(4)) or more particles, determining the equilibrium shape of small colloidal assemblies of O(10) particles requires a generalized Wulff construction technique which we have developed for a proper description of equilibrium structure and morphology of small crystals. We identify and characterize fully several "magic" clusters which are significantly more stable than other similarly sized clusters.

  4. Updated Coronal Equilibrium Calculations

    NASA Astrophysics Data System (ADS)

    Bryans, Paul; Badnell, N. R.; Gorczyca, T. W.; Laming, J. M.; Mitthumsiri, W.; Savin, D. W.

    2006-06-01

    Reliably interpreting solar spectra requires accurate ionization balance calculations. However, much of the atomic data needed for these calculations have not been generated using modern theoretical methods and are often highly suspect. This translates directly into the reliability of the collisional ionization equilibrium (CIE) calculations. We make use of state-of-the-art calculations of dielectronic recombination (DR) rate coefficients for the hydrogenic through Na-like ions of all elements from He through to Zn. We also make use of state-of-the-art radiative recombination (RR) rate coefficient calculations for the bar e through Na-like ions of all elements from H to Zn. Here we present improved CIE calculations for temperatures from 1e4 to 1e9 K using our data and the recommended electron impact ionization data of Mazzotta et al. (1998, A&AS, 133, 403) for elements up through Ni and Mazzotta (private communication) for Cu and Zn. DR and RR data for ionization stages that have not been updated are also taken from these two additional sources. We compare our calculated fractional ionic abundances using these data with those presented by Mazzotta et al. for all elements from H to Ni. The differences in peak fractional abundance are up to 60%. We also compare with the fractional ionic abundances for Mg, Si, S, Ar, Ca, Fe, and Ni derived from the modern DR calculations of Gu (2003a, ApJ, 590, 1131; 2004, ApJ, 153, 389) for the H-like through Na-like ions, and the RR calculations of Gu (2003b, ApJ, 589, 1085) for the bare through F-like ions. These results are in better agreement with our work, with differences in peak fractional abundance of less than 10%. This work was supported in part by the NASA Solar SR&T and LWS programs, theOffice of Naval Research, and PPARC.

  5. Non-equilibrium supramolecular polymerization.

    PubMed

    Sorrenti, Alessandro; Leira-Iglesias, Jorge; Markvoort, Albert J; de Greef, Tom F A; Hermans, Thomas M

    2017-03-28

    Supramolecular polymerization has been traditionally focused on the thermodynamic equilibrium state, where one-dimensional assemblies reside at the global minimum of the Gibbs free energy. The pathway and rate to reach the equilibrium state are irrelevant, and the resulting assemblies remain unchanged over time. In the past decade, the focus has shifted to kinetically trapped (non-dissipative non-equilibrium) structures that heavily depend on the method of preparation (i.e., pathway complexity), and where the assembly rates are of key importance. Kinetic models have greatly improved our understanding of competing pathways, and shown how to steer supramolecular polymerization in the desired direction (i.e., pathway selection). The most recent innovation in the field relies on energy or mass input that is dissipated to keep the system away from the thermodynamic equilibrium (or from other non-dissipative states). This tutorial review aims to provide the reader with a set of tools to identify different types of self-assembled states that have been explored so far. In particular, we aim to clarify the often unclear use of the term "non-equilibrium self-assembly" by subdividing systems into dissipative, and non-dissipative non-equilibrium states. Examples are given for each of the states, with a focus on non-dissipative non-equilibrium states found in one-dimensional supramolecular polymerization.

  6. Congenital Anomaly of the Atlas Misdiagnosed as Posterior Arch Fracture of the Atlas and Atlantoaxial Subluxation

    PubMed Central

    Park, Yung; Kim, Seong Min; Lee, Yun Tae; Yoo, Ju Hyung; Oh, Hyun Chul; Sung, Seung Yong; Yoon, Han Kook; Chang, Jee-Hoon; Jung, Jeung-Yeul

    2014-01-01

    Partial or complete absence of the posterior arch of the atlas is a well-documented anomaly but a relatively rare condition. This condition is usually asymptomatic so most are diagnosed incidentally. There have been a few documented cases of congenital defects of the posterior arch of the atlas combined with atlantoaxial subluxation. We report a very rare case of congenital anomaly of the atlas combined with atlantoaxial subluxation, that can be misdiagnosed as posterior arch fracture. PMID:24605195

  7. 13. Photocopy of a photographca. 1896showing wooden arch bridge over ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    13. Photocopy of a photograph--ca. 1896--showing wooden arch bridge over the North Fork of the San Joaquin River northeast of Fresno, CA. This structure was designed by Eastwood as part of the San Joaquin Electric Company's hydro-electric plant; it is a design that indicates his interest in the structural capabilities of the arch before he began building multiple arch dams. Courtesy Mr. Charles Allan Whitney. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

  8. Helical axis stellarator equilibrium model

    SciTech Connect

    Koniges, A.E.; Johnson, J.L.

    1985-02-01

    An asymptotic model is developed to study MHD equilibria in toroidal systems with a helical magnetic axis. Using a characteristic coordinate system based on the vacuum field lines, the equilibrium problem is reduced to a two-dimensional generalized partial differential equation of the Grad-Shafranov type. A stellarator-expansion free-boundary equilibrium code is modified to solve the helical-axis equations. The expansion model is used to predict the equilibrium properties of Asperators NP-3 and NP-4. Numerically determined flux surfaces, magnetic well, transform, and shear are presented. The equilibria show a toroidal Shafranov shift.

  9. Equilibrium ignition for ICF capsules

    SciTech Connect

    Lackner, K.S.; Colgate, S.A.; Johnson, N.L.; Kirkpatrick, R.C.; Menikoff, R.; Petschek, A.G. )

    1994-10-05

    In comparing high-gain ICF targets using cryogenic DT for a pusher with equilibrium ignition targets using high-[ital Z] pushers which contain the radiation, we point to the intrinsic advantages of the latter. Equilibrium or volume ignition sacrifices high gain for lower losses, lower ignition temperature, lower implosion velocity, and lower sensitivity of the more robust capsule to small fluctuations and asymmetries in the drive system. The reduction in gain is about a factor of 2.5, which is small enough to make the more robust equilibrium ignition an atractive alternative. [copyright] 1994 [ital American] [ital Institute] [ital of] [ital Physics

  10. Interregional equilibrium with heterogeneous labor.

    PubMed

    Michel, P; Perrot, A; Thisse J-f

    1996-02-01

    "The impact of labor migration on interregional equilibrium is studied when workers are heterogeneous in productivity and regional mobility. The skilled respond to market disequilibrium by moving into the most attractive region. The unskilled are immobile in the short-run and move with the skilled in the long-run. Both regions have a neoclassical production function affected by an externality depending on the number of skilled. Workers move according to the utility differential when regional amenities vary with population or according to the wage differential. The equilibrium pattern depends on the unskilled's mobility and on migration incentives. Typically, regional imbalance characterizes the equilibrium which is often suboptimal."

  11. Out-of-plane free vibration analysis of a cable-arch structure

    NASA Astrophysics Data System (ADS)

    Kang, H. J.; Zhao, Y. Y.; Zhu, H. P.

    2013-02-01

    Cable-arch structure has been widely used in many long-span structures such as cable roofs and cable-stayed arch bridges, but its dynamics is still not well understood. In this paper, the out-of-plane dynamic behavior of a cable-arch structure is investigated. The equations governing the out-of-plane free vibration of the structure are derived using d'Alembert's principle. A transfer matrix method is used to solve the governing equations and determine the frequencies of the out-of-plane vibration. The theories are then used to study two specific cases: free vibration of a model cable-arch and simulation of an arch erection process. The effects of some key parameters of cable and arch, such as tension of cable and radius, open-angle and shape of arch, are examined. The results indicate that in-plane and spatial cables can largely improve the out-of-plane dynamic behavior of arch structures, which are further verified by analyzing the out-of-plane buckling of cable-arch structures. The present work should be valuable and significant not only for the fundamental research but also engineering design of roofs and bridges.

  12. Ball motion and sliding friction in an arched outer race ball bearing

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.

    1973-01-01

    The motion of the ball and sliding friction in an arched outer race ball bearing under thrust loads is determined. Fatigue life evaluations were made. The analysis is applied to a 150 millimeter bore ball bearing. The results indicated that for high speed-light load applications the arched bearing has significant improvement in fatigue life over that of a conventional bearing. An arching of 0.254 mm (0.01 in.) was found to be an optimal. For an arched bearing it was also found that a considerable amount of spinning occurs at the outer race contacts.

  13. Ball motion and sliding friction in an arched outer-race ball bearing

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.

    1974-01-01

    The motion of the ball and sliding friction in an arched outer-race ball bearing under thrust load is analyzed. Fatigue life evaluations were made. The analysis is applied to a 150-millimeter-bore ball bearing. The results indicated that for high-speed light-load applications the arched bearing has significant improvement in fatigue life over that of a conventional bearing. An arching of 0.254 mm (0.01 in.) was found to be optimal. Also, for an arched bearing a considerable amount of spinning occurs at the outer-race contacts.

  14. Ball motion and sliding friction in an arched outer race ball bearing

    NASA Technical Reports Server (NTRS)

    Hamrock, B. J.

    1974-01-01

    The motion of the ball and sliding friction in an arched outer-race ball bearing under thrust load is determined. Fatigue life evaluations were made. The analysis is applied to a 150 millimeter bore ball bearing. The results indicated that for high speed-light load applications the arched bearing has significant improvement in fatigue life over that of a conventional bearing. An arching of 0.254 mm (0.01 in.) was found to be an optimal. For an arched bearing it was also found that a considerable amount of spinning occurs at the outer race contacts.

  15. [Diagnosis and follow-up of reduction of fractures of the zygomatic arch].

    PubMed

    Friedrich, R E; Volkenstein, R J

    1994-08-01

    Ultrasound and standard x-ray investigations before and after the reduction of the fractures were performed in 17 patients with zygomatic arch fractures. The ultrasound investigation of the bone surface is recommended as an additional diagnostic tool in the diagnosis and control of the reduction of zygomatic arch fractures. Intraoperative ultrasound imaging under sterile conditions is easy to apply and enables the surgeon to optimise therapeutic results. In 5 cases based on an intraoperative sonogram further reductions of zygomatic arch fractures were carried out. In another referred patient the diagnosis of a zygomatic arch fracture was excluded by ultrasound and confirmed by standard x-ray examinations.

  16. Mesodermal retinoic acid signaling regulates endothelial cell coalescence in caudal pharyngeal arch artery vasculogenesis

    PubMed Central

    Li, Peng; Pashmforoush, Mohammad; Sucov, Henry M.

    2011-01-01

    Disruption of retinoic acid signaling causes a variety of pharyngeal arch artery and great vessel defects, as well as malformations in many other tissues, including those derived from the pharyngeal endoderm. Previous studies implied that arch artery defects in the context of defective RA signaling occur secondary to pharyngeal pouch segmentation defects, although this model has never been experimentally verified. In this study, we examined arch artery morphogenesis during mouse development, and the role of RA in this process. We show in normal embryos that the arch arteries form by vasculogenic differentiation of pharyngeal mesoderm. Using various genetic backgrounds and tissue-specific mutation approaches, we segregate pharyngeal arch artery and pharyngeal pouch defects in RA receptor mutants, and show that RA signal transduction only in pharyngeal mesoderm is required for arch artery formation. RA does not control pharyngeal mesodermal differentiation to endothelium, but instead promotes the aggregation of endothelial cells into nascent vessels. Expression of VE-cadherin was substantially reduced in RAR mutants, and this deficiency may underlie the arch artery defects. The consequences of disrupted mesodermal and endodermal RA signaling were restricted to the 4th and 6th arch arteries and to the 4th pharyngeal pouch, respectively, suggesting that different regulatory mechanisms control the formation of the more anterior arch arteries and pouches. PMID:22040871

  17. New classification of lingual arch form in normal occlusion using three dimensional virtual models

    PubMed Central

    Park, Kyung Hee; Bayome, Mohamed; Park, Jae Hyun; Lee, Jeong Woo; Baek, Seung-Hak

    2015-01-01

    Objective The purposes of this study were 1) to classify lingual dental arch form types based on the lingual bracket points and 2) to provide a new lingual arch form template based on this classification for clinical application through the analysis of three-dimensional virtual models of normal occlusion sample. Methods Maxillary and mandibular casts of 115 young adults with normal occlusion were scanned in their occluded positions and lingual bracket points were digitized on the virtual models by using Rapidform 2006 software. Sixty-eight cases (dataset 1) were used in K-means cluster analysis to classify arch forms with intercanine, interpremolar and intermolar widths and width/depth ratios as determinants. The best-fit curves of the mean arch forms were generated. The remaining cases (dataset 2) were mapped into the obtained clusters and a multivariate test was performed to assess the differences between the clusters. Results Four-cluster classification demonstrated maximum intercluster distance. Wide, narrow, tapering, and ovoid types were described according to the intercanine and intermolar widths and their best-fit curves were depicted. No significant differences in arch depths existed among the clusters. Strong to moderate correlations were found between maxillary and mandibular arch widths. Conclusions Lingual arch forms have been classified into 4 types based on their anterior and posterior dimensions. A template of the 4 arch forms has been depicted. Three-dimensional analysis of the lingual bracket points provides more accurate identification of arch form and, consequently, archwire selection. PMID:25798413

  18. Syndromes of the first and second pharyngeal arches: A review.

    PubMed

    Passos-Bueno, Maria Rita; Ornelas, Camila C; Fanganiello, Roberto D

    2009-08-01

    Our aim in this review is to discuss currently known mechanisms associated with three important syndromes of the first and second pharyngeal arches: Treacher Collins syndrome (TCS), Oculo-auriculo-vertebral syndrome (AOVS) and Auriculo-Condylar syndrome (ACS) or question mark ear syndrome. TCS and ACS are autosomal dominant diseases, with nearly complete penetrance and wide spectrum of clinical variability. The phenotype of the latter has several overlapping features with OAVS, but OAVS may exist in both sporadic and autosomal dominant forms. Mutations in the TCOF1 gene are predicted to cause premature termination codons, leading to haploinsuficiency of the protein treacle and causing TCS. Low amount of treacle leads ultimately to a reduction in the number of cranial neural crest cells migrating to the first and second pharyngeal arches. Other than TCS, the genes associated with ACS and OAVS are still unknown. The first locus for ACS was mapped by our group to 1p21-23 but there is genetic heretogeneity. Genetic heterogeneity is also present in OAVS. Based on the molecular analysis of balanced translocation in an OAVS patient, it has been suggested that abnormal expression of BAPX1 possibly due to epigenetic disregulation might be involved with the etiology of OAVS. Involvement of environmental events has also been linked to the causation of OAVS. Identification of factors leading to these disorders are important for a comprehensive delineation of the molecular pathways underlying the craniofacial development from the first and the second pharyngeal arches, for genetic counseling and to open alternative strategies for patient treatment.

  19. Combined Open and Endovascular Repair for Aortic Arch Pathology

    PubMed Central

    Kang, Woong Chol; Ahn, Tae Hoon; Lee, Kyung Hoon; Moon, Chan Il; Han, Seung Hwan; Park, Chul-Hyun; Park, Kook-Yang; Kang, Jin Mo; Kim, Jung Ho

    2010-01-01

    Background and Objectives We describe our experience with combined open and endovascular repair in patients who have aortic arch pathology. Subjects and Methods This study is a retrospective analysis of 7 patients who underwent combined open and endovascular repair for aortic arch pathology. Medical records and radiographic information were reviewed. Results A total of 7 consecutive patients (5 men, 71.4%) underwent thoracic stent graft implantation. The mean age was 59.9±16.7 years. The indication for endovascular repair was aneurysmal degeneration in 5 patients, and rupture or impending rupture in 2 patients. In all 7 cases, supra-aortic transposition of the great vessels was performed successfully. Stent graft implantation was achieved in all cases. Surgical exposure of the access vessel was necessary in 2 patients. A total of 9 stent grafts were implanted (3 stent grafts in one patient). The Seal thoracic and the Valiant endovascular stent graft were implanted in 6 patients and 1 patient, respectively. There were no post-procedure deaths or neurologic complications. In 2 patients, bleeding and injury of access vessel were noted after the procedure. Postoperative endoleak was noted in 1 patient. One patient died at 10 months after the procedure due to a newly developed ascending aortic dissection. No patients required secondary intervention during the follow-up period. The aortic diameter decreased in 4 patients. In 3 patients, including 1 patient with endoleak, there was no change in aortic diameter. Conclusion Our experience suggests that combined open and endovascular repair for aortic arch pathology is safe and effective, with few complications. PMID:20830254

  20. Atherosclerotic Plaques in the Aortic Arch and Subclinical Cerebrovascular Disease.

    PubMed

    Tugcu, Aylin; Jin, Zhezhen; Homma, Shunichi; Elkind, Mitchell S V; Rundek, Tatjana; Yoshita, Mitsuhiro; DeCarli, Charles; Nakanishi, Koki; Shames, Sofia; Wright, Clinton B; Sacco, Ralph L; Di Tullio, Marco R

    2016-11-01

    Aortic arch plaque (AAP) is a risk factor for ischemic stroke, but its association with subclinical cerebrovascular disease is not established. We investigated the association between AAP and subclinical cerebrovascular disease in an elderly stroke-free community-based cohort. The CABL study (Cardiovascular Abnormalities and Brain Lesions) was designed to investigate cardiovascular predictors of silent cerebrovascular disease in the elderly. AAPs were assessed by suprasternal transthoracic echocardiography in 954 participants. Silent brain infarcts and white matter hyperintensity volume (WMHV) were assessed by brain magnetic resonance imaging. The association of AAP thickness with silent brain infarcts and WMHV was evaluated by logistic regression analysis. Mean age was 71.6±9.3 years; 63% were women. AAP was present in 658 (69%) subjects. Silent brain infarcts were detected in 138 participants (14.5%). In multivariate analysis adjusted for potential confounders, AAP thickness and large AAP (≥4 mm in thickness) were significantly associated with the upper quartile of WMHV (WMHV-Q4; odds ratio =1.17; 95% confidence interval, 1.04-1.32; P=0.009 and odds ratio =1.79; 95% confidence interval, 1.40-3.09; P=0.036, respectively), but not with silent brain infarcts (odds ratio =1.08; 95% confidence interval, 0.94-1.23; P=0.265 and odds ratio =1.46; 95% confidence interval, 0.77-2.77; P=0.251, respectively). Aortic arch atherosclerosis was associated with WMHV in a stroke-free community-based elderly cohort. This association was stronger in subjects with large plaques and independent of cardiovascular risk factors. Aortic arch assessment by transthoracic echocardiography may help identify subjects at higher risk of subclinical cerebrovascular disease, who may benefit from aggressive stroke risk factors treatment. © 2016 American Heart Association, Inc.

  1. Base line sequence stratigraphy, Arkoma Basin to Chautauqua Arch

    SciTech Connect

    Bennison, A.P.

    1993-02-01

    Use of sequence stratigraphy concepts requires some caution, especially if these are based almost solely on theoretical models enhanced by a computer data base or by seismic records where lithologic interpretations are assumed rather than observed. Optimum input for sequence models is obtained from actual stratigraphic data from outcrops, cuttings and cores across sedimentary strike, such as those from the Arkoma Basin northward to the Chautauqua Arch along the Oklahoma-Kansas border area. Sequence stratigraphy involving Pennsylvanian data indicates a major northward shift of the Arkoma Basin paleobathymetric axis from the southern Ouachita Mountains to southern Kansas with some occasional backward and forward motion. This long base line is also needed to ascertain the total number of parasequences (transgressive-regressive cycles), their geometric succession, and interrelationship of low-stand, shelf-margin, transgressive high-stand, and condensed system tracks. The first two system tracts are important for productive reservoirs, whereas the latter three usually serve as prime source beds. Usually not all parasequences are present at any one place along an established base line or transect. The low-stand or shelf-margin parasequences are usually absent on the craton or on interbasinal or intrabasinal arches such as the Chautauqua Arch, whereas the transgressive and high-stand parasequences commonly thin basinward into condensed sequences or disappear through downlapping. Actual Pennsylvania outcrop data commonly differ from the standard sequence stratigraphy model of Exxon and Peter Vai. Sequence boundaries based on unconformities may occur at any place within a parasequence and may change places along the baseline.

  2. Distribution of dental plaque and gingivitis within the dental arches.

    PubMed

    Sreenivasan, Prem K; Prasad, Kakarla V V

    2017-10-01

    Objective The natural accumulation of supragingival plaque on surfaces of human teeth is associated with gingival inflammation and the initiation of common oral diseases. This study evaluated the distribution of dental plaque and gingivitis scores within the dental arches after prophylaxis. Methods Adult subjects from the Dharwad, India area representing the general population who provided written informed consent were scheduled for screening. Healthy subjects over the age of 18 years, not currently requiring any medical or dental care, and presenting with a complement of at least 20 natural teeth were recruited for this parallel design study. Enrolled subjects (n = 41) underwent oral examinations for dental plaque (PI) and gingivitis (GI) using the Turesky modification of the Quigley-Hein and the Löe-Silness Index, respectively, at the baseline visit, followed by a whole mouth dental prophylaxis. Subjects were given fluoride toothpaste for twice daily oral hygiene for the next 30 days. Subjects were recalled on days 15 and 30 for PI and GI examinations identical to baseline. Results Analyses indicated that mean scores for PI and GI on either arch and the whole mouth were higher than 2 and 1, respectively, during all examinations. Anterior surfaces consistently exhibited lower PI scores than posterior regions of either arch, or the entire dentition. Regional GI differences within the dentition were similar to PI scores, with lower scores on anterior than posterior teeth. Prophylaxis reduced both the frequency and mean scores of both PI and GI, irrespective of arch, with lower scores observed on anterior than posterior regions during all recall visits. Molar and lingual regions consistently exhibited higher PI and GI scores compared with anterior surfaces. At all examinations, mean scores for both plaque and gingivitis were higher on approximal vestibular than mid-vestibular surfaces. Conclusions Differences observed in PI and GI within the dentition have

  3. Further Exploration of Post-Flare Giant Arches

    NASA Astrophysics Data System (ADS)

    West, Matthew; Seaton, Daniel B.; Dennis, Brian R.; feng, Li

    2017-08-01

    Recent observations from the SWAP EUV imager on-board PROBA2 and SXI X-ray observations from the GOES satellite have shown that post-flare giant arches and regular post-flare loops are one and the same thing. However, it is still not clear how certain loop systems are able to sustain prolonged growth to heights of approximately 400000 km (>0.5 solar-radii). In this presentation we further explore the energy deposition rate above post-flare loop systems through high-energy RHESSI observations. We also explore the difference between the loop systems through a multi-wavelength epoch analysis.

  4. Effects of different medial arch support heights on rearfoot kinematics

    PubMed Central

    Mayer, Frank; Baur, Heiner

    2017-01-01

    Background Foot orthoses are usually assumed to be effective by optimizing mechanically dynamic rearfoot configuration. However, the effect from a foot orthosis on kinematics that has been demonstrated scientifically has only been marginal. The aim of this study was to examine the effect of different heights in medial arch-supported foot orthoses on rear foot motion during gait. Methods Nineteen asymptomatic runners (36±11years, 180±5cm, 79±10kg; 41±22km/week) participated in the study. Trials were recorded at 3.1 mph (5 km/h) on a treadmill. Athletes walked barefoot and with 4 different not customized medial arch-supported foot orthoses of various arch heights (N:0 mm, M:30 mm, H:35 mm, E:40mm). Six infrared cameras and the `Oxford Foot Model´ were used to capture motion. The average stride in each condition was calculated from 50 gait cycles per condition. Eversion excursion and internal tibia rotation were analyzed. Descriptive statistics included calculating the mean ± SD and 95% CIs. Group differences by condition were analyzed by one factor (foot orthoses) repeated measures ANOVA (α = 0.05). Results Eversion excursion revealed the lowest values for N and highest for H (B:4.6°±2.2°; 95% CI [3.1;6.2]/N:4.0°±1.7°; [2.9;5.2]/M:5.2°±2.6°; [3.6;6.8]/H:6.2°±3.3°; [4.0;8.5]/E:5.1°±3.5°; [2.8;7.5]) (p>0.05). Range of internal tibia rotation was lowest with orthosis H and highest with E (B:13.3°±3.2°; 95% CI [11.0;15.6]/N:14.5°±7.2°; [9.2;19.6]/M:13.8°±5.0°; [10.8;16.8]/H:12.3°±4.3°; [9.0;15.6]/E:14.9°±5.0°; [11.5;18.3]) (p>0.05). Differences between conditions were small and the intrasubject variation high. Conclusion Our results indicate that different arch support heights have no systematic effect on eversion excursion or the range of internal tibia rotation and therefore might not exert a crucial influence on rear foot alignment during gait. PMID:28257426

  5. Equilibrium and Orientation in Cephalopods.

    ERIC Educational Resources Information Center

    Budelmann, Bernd-Ulrich

    1980-01-01

    Describes the structure of the equilibrium receptor system in cephalopods, comparing it to the vertebrate counterpart--the vestibular system. Relates the evolution of this complex system to the competition of cephalopods with fishes. (CS)

  6. Equilibrium ignition for ICF capsules

    SciTech Connect

    Lackner, K.S.; Colgate, S.A.; Johnson, N.L.; Kirkpatrick, R.C.; Menikoff, R.; Petschek, A.G.

    1993-12-31

    There are two fundamentally different approaches to igniting DT fuel in an ICF capsule which can be described as equilibrium and hot spot ignition. In both cases, a capsule which can be thought of as a pusher containing the DT fuel is imploded until the fuel reaches ignition conditions. In comparing high-gain ICF targets using cryogenic DT for a pusher with equilibrium ignition targets using high-Z pushers which contain the radiation. The authors point to the intrinsic advantages of the latter. Equilibrium or volume ignition sacrifices high gain for lower losses, lower ignition temperature, lower implosion velocity and lower sensitivity of the more robust capsule to small fluctuations and asymmetries in the drive system. The reduction in gain is about a factor of 2.5, which is small enough to make the more robust equilibrium ignition an attractive alternative.

  7. Simulations for Teaching Chemical Equilibrium

    NASA Astrophysics Data System (ADS)

    Huddle, Penelope A.; White, Margaret Dawn; Rogers, Fiona

    2000-07-01

    This paper outlines a systematic approach to teaching chemical equilibrium using simulation experiments that address most known alternate conceptions in the topic. Graphs drawn using the data from the simulations are identical to those obtained using real experimental data for reactions that go to equilibrium. This allows easy mapping of the analogy to the target. The requirements for the simulations are simple and inexpensive, making them accessible to even the poorest schools. The simulations can be adapted for all levels, from pupils who are first encountering equilibrium through students in tertiary education to qualified teachers who have experienced difficulty in teaching the topic. The simulations were piloted on four very different audiences. Minor modifications were then made before the Equilibrium Games as reported in this paper were tested on three groups of subjects: a Grade 12 class, college students, and university Chemistry I students. Marked improvements in understanding of the concept were shown in two of the three sets of subjects.

  8. Equilibrium Constants You Can Smell.

    ERIC Educational Resources Information Center

    Anderson, Michael; Buckley, Amy

    1996-01-01

    Presents a simple experiment involving the sense of smell that students can accomplish during a lecture. Illustrates the important concepts of equilibrium along with the acid/base properties of various ions. (JRH)

  9. Equilibrium and Orientation in Cephalopods.

    ERIC Educational Resources Information Center

    Budelmann, Bernd-Ulrich

    1980-01-01

    Describes the structure of the equilibrium receptor system in cephalopods, comparing it to the vertebrate counterpart--the vestibular system. Relates the evolution of this complex system to the competition of cephalopods with fishes. (CS)

  10. [Clinical study of treatment effects on deep overbite: a comparison between Multiloop edgewise arch wire and manufactured artificial NiTi reverse-curve arch].

    PubMed

    Zhang, Hong-jun

    2010-06-01

    To evaluate the effects of multiloop edgewise arch wire(MEAW) and NiTi reverse-curve arch in correcting deep overbite. Twenty cases(12-27 year of age)with deep overbite were treated with MEAW or NiTi reverse-curve arch. Pre-and post-treatment cephalogram were taken and analyzed. SPSS13.0 software package was used for paired t test. Two methods could intrude incisors and extrude molars.Maxilla and mandibular had no apparent changes, but less time was spent in the MEAW group. Two methods could correct deep overbite by the same mechanism, but the MEAW has more effective results.

  11. A search for equilibrium states

    NASA Technical Reports Server (NTRS)

    Zeleznik, F. J.

    1982-01-01

    An efficient search algorithm is described for the location of equilibrium states in a search set of states which differ from one another only by the choice of pure phases. The algorithm has three important characteristics: (1) it ignores states which have little prospect for being an improved approximation to the true equilibrium state; (2) it avoids states which lead to singular iteration equations; (3) it furnishes a search history which can provide clues to alternative search paths.

  12. Edge equilibrium code for tokamaks

    SciTech Connect

    Li, Xujing; Drozdov, Vladimir V.

    2014-01-15

    The edge equilibrium code (EEC) described in this paper is developed for simulations of the near edge plasma using the finite element method. It solves the Grad-Shafranov equation in toroidal coordinate and uses adaptive grids aligned with magnetic field lines. Hermite finite elements are chosen for the numerical scheme. A fast Newton scheme which is the same as implemented in the equilibrium and stability code (ESC) is applied here to adjust the grids.

  13. Relevance of equilibrium in multifragmentation

    SciTech Connect

    Furuta, Takuya; Ono, Akira

    2009-01-15

    The relevance of equilibrium in a multifragmentation reaction of very central {sup 40}Ca + {sup 40}Ca collisions at 35 MeV/nucleon is investigated by using simulations of antisymmetrized molecular dynamics (AMD). Two types of ensembles are compared. One is the reaction ensemble of the states at each reaction time t in collision events simulated by AMD, and the other is the equilibrium ensemble prepared by solving the AMD equation of motion for a many-nucleon system confined in a container for a long time. The comparison of the ensembles is performed for the fragment charge distribution and the excitation energies. Our calculations show that there exists an equilibrium ensemble that well reproduces the reaction ensemble at each reaction time t for the investigated period 80{<=}t{<=}300 fm/c. However, there are some other observables that show discrepancies between the reaction and equilibrium ensembles. These may be interpreted as dynamical effects in the reaction. The usual static equilibrium at each instant is not realized since any equilibrium ensemble with the same volume as that of the reaction system cannot reproduce the fragment observables.

  14. An Upper and Middle Cervical Spine Posterior Arch Defect Leading to Myelopathy and a Thoracic Spine Posterior Arch Defect.

    PubMed

    Yun, Dong-Ju; Hwang, Byeong-Wook; Kim, Dae Jin; Lee, Sang-Ho

    2016-09-01

    Abnormalities of the posterior arches of the upper and middle cervical spine that can cause myelopathy are rare, and no reports of such defects at the thoracic spinal level have been published. A 29-year-old male patient reported right arm weakness and pain for 1 year. Magnetic resonance imaging of the cervical spine showed spinal canal stenosis at the C3-4 and C4-5 levels, as well as a posterior arch defect at the C2, 3, and 4 levels that was compressing the spinal cord. Three-dimensional cervical computed tomography (CT) showed that the spinous process and a piece of lamina were fused at each of the posterior C2, 3, and 4 levels, producing a free-floating bony structure. Spina bifida occulta was observed at C1. Osseous formation had failed between the lateral mass and spinous process at the C2 and C3 levels bilaterally, and the C4 level unilaterally. Three-dimensional thoracolumbar CT showed blocked vertebrae and spinous process fusion at T11 and T12. Osseous formation had failed between the lamina and spinous process at the T11 level unilaterally, and the T12 level bilaterally. The free-floating bony structure was successfully removed surgically. A posterior arch defect of the upper and middle cervical spine leading to myelopathy combined with the same defect at the thoracic spine is a rare disease. If this congenital defect is detected at any spinal level, whole-spine CT can be helpful for accurately diagnosing the congenital anomaly. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Clinical Significance of the Axillary Arch in Sentinel Lymph Node Biopsy

    PubMed Central

    Lee, Jeong Eon; Nam, Seok Jin

    2014-01-01

    Purpose The axillary arch is an anomalous muscle that is not infrequently encountered during axillary sentinel lymph node biopsy (SLNB) of breast cancer patients. In this study, we aimed to investigate how often the axillary arch is found during SLNB and whether it affects the intraoperative sentinel lymph node (SLN) identification rate. Methods We retrospectively analyzed the correlation between the presence of the axillary arch and the SLN sampling failure rate during SLNB in 1,069 patients who underwent axillary SLNB for invasive breast cancer. Results Of 1,069 patients who underwent SLNB, 79 patients (7.4%) had the axillary arch present. The SLNB failure rate was high when the patient's body mass index was ≥25 (p=0.026), when a single SLN mapping technique was used (p=0.012), and when the axillary arch was present (p<0.001). These three factors were also found to be statistically significant by multivariate analysis, and of these three factors, presence of the axillary arch most significantly increased the SLNB failure rate (hazard ratio, 10.96; 95% confidence interval, 4.42-27.21; p<0.001). Additionally, if the axillary arch was present, the mean operative time of SLNB was 20.8 minutes, compared to 12.5 minutes when the axillary arch was not present (p<0.001). If the axillary arch was present, the SLN was often located in a high axillary region (67%) rather than in a general low axillary location. Conclusion The axillary arch was found to be a significant factor affecting intraoperative SLN failure rate. It is necessary to keep in mind that carefully checking the high axillar region during SLNB in breast cancer patients with the axillary arch is important for reducing SLN sampling failure. PMID:25320622

  16. Clinical significance of the axillary arch in sentinel lymph node biopsy.

    PubMed

    Kil, Won Ho; Lee, Jeong Eon; Nam, Seok Jin

    2014-09-01

    The axillary arch is an anomalous muscle that is not infrequently encountered during axillary sentinel lymph node biopsy (SLNB) of breast cancer patients. In this study, we aimed to investigate how often the axillary arch is found during SLNB and whether it affects the intraoperative sentinel lymph node (SLN) identification rate. We retrospectively analyzed the correlation between the presence of the axillary arch and the SLN sampling failure rate during SLNB in 1,069 patients who underwent axillary SLNB for invasive breast cancer. Of 1,069 patients who underwent SLNB, 79 patients (7.4%) had the axillary arch present. The SLNB failure rate was high when the patient's body mass index was ≥25 (p=0.026), when a single SLN mapping technique was used (p=0.012), and when the axillary arch was present (p<0.001). These three factors were also found to be statistically significant by multivariate analysis, and of these three factors, presence of the axillary arch most significantly increased the SLNB failure rate (hazard ratio, 10.96; 95% confidence interval, 4.42-27.21; p<0.001). Additionally, if the axillary arch was present, the mean operative time of SLNB was 20.8 minutes, compared to 12.5 minutes when the axillary arch was not present (p<0.001). If the axillary arch was present, the SLN was often located in a high axillary region (67%) rather than in a general low axillary location. The axillary arch was found to be a significant factor affecting intraoperative SLN failure rate. It is necessary to keep in mind that carefully checking the high axillar region during SLNB in breast cancer patients with the axillary arch is important for reducing SLN sampling failure.

  17. Double aortic arch anomalies in Children: A Systematic 20-Year Single Center Study.

    PubMed

    Kaldararova, M; Simkova, I; Varga, I; Tittel, P; Kardos, M; Ondriska, M; Vrsanska, V; Masura, J

    2017-10-01

    Aortic arch anomalies underlie numerous congenital disorders. Effectively diagnosing and treating them requires close understanding of cardiovascular embryology. As our Center serves the entire pediatric population of our country, we performed a comprehensive retrospective analysis of all aortic arch anomalies diagnosed at our Center over the past 20 years. We analyzed 40 children with aortic arch anomalies, distinguishing two defect types: Group 1 displayed ring-forming anomalies, and Group 2 other types of aortic arch anomalies that did not form a vascular ring. We performed detailed morphological analyses using echocardiography, angiography, computed tomography, or magnetic resonance imaging and generated a catalog of all aortic arch anomalies present. Group 1 was represented by 25 patients; 40% with persistent both aortic arches, and 60% with various forms of right aortic arch and an incomplete left aortic arch. Group 2 was represented by 15 patients with complex heart defects. On the basis of our dataset, the incidence of all aortic arch anomalies was 0.033%, and of ring-forming pathologies 0.021%. Although aortic arch anomalies are rare, it is important to diagnose them correctly. It is critical to distinguish ring-forming types. Although in complex defects the aortic arch anomaly represents only an additive diagnosis, its correct definition could be crucial for further management. Cumulatively, this unique, long-term study provides a systematic patient registry and offers critical epidemiological data to aid the study of rare congenital cardiovascular defects. Clin. Anat. 30:929-939, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  18. Sagittal movement of the medial longitudinal arch is unchanged in plantar fasciitis.

    PubMed

    Wearing, Scott C; Smeathers, James E; Yates, Bede; Sullivan, Patrick M; Urry, Stephen R; Dubois, Philip

    2004-10-01

    Although a lowered medial longitudinal arch has been cited as a causal factor in plantar fasciitis, there is little experimental evidence linking arch motion to the pathogenesis of the condition. This study investigated the sagittal movement of the arch in subjects with and without plantar fasciitis during gait. Digital fluoroscopy was used to acquire dynamic lateral radiographs from 10 subjects with unilateral plantar fasciitis and 10 matched control subjects. The arch angle and the first metatarsophalangeal joint angle were digitized and their respective maxima recorded. Sagittal movement of the arch was defined as the angular change between heel strike and the maximum arch angle observed during the stance phase of gait. The thickness of the proximal plantar fascia was determined from sagittal sonograms of both feet. ANOVA models were used to identify differences between limbs with respect to each dependent variable. Relationships between arch movement and fascial thickness were investigated using correlations. There was no significant difference in either the movement or maximum arch angle between limbs. However, subjects with plantar fasciitis were found to have a larger metatarsophalangeal joint angle than controls (P < 0.05). Whereas the symptomatic and asymptomatic plantar fascia were thicker than those of control feet (P < 0.05), significant correlations were noted between fascial thickness and peak arch and metatarsophalangeal joint angles (P < 0.05) in the symptomatic limb only. Neither abnormal shape nor movement of the arch are associated with chronic plantar fasciitis. However, arch mechanics may influence the severity of plantar fasciitis, once the condition is present. Digital flexion, in contrast, has a protective role in what might be a bilateral disease process.

  19. A mathematic-geometric model to calculate variation in mandibular arch form.

    PubMed

    Mutinelli, S; Manfredi, M; Cozzani, M

    2000-04-01

    A mathematic-geometric model was used to evaluate the variation of mandibular dental arch length with respect to the incisor inclination, but without modifying the intercanine width. In analytical terms, the equations of the curves representing the lower dental arch, before and after incisor inclination of 1 mm and of 1 degree, with controlled and uncontrolled tipping, were studied. The length of the mandibular dental arch changed in the parabolic arch form by 1.51 mm for each millimetre of incisor inclination with respect to the occlusal functional plane, by 0.54 mm for each degree of controlled tipping and by 0.43 mm for each degree of uncontrolled tipping. In the elliptical arch form (e = 0.78), it changed by 1.21, 0.43, and 0.34 mm, respectively, in the hyperbolic form by 1.61, 0.57, and 0.46 mm, in the circular form by 1.21, 0.43, and 0.34 mm, and in the catenary form by 2.07, 0.74, and 0.59 mm. The results show that by changing the arch form without modifying the dimension of the dental arch, different arch lengths can be gained for each millimetre of proclination. In addition, by controlled tipping an inter-incisive arch one-fifth longer than by uncontrolled tipping can be obtained. It would be advisable in orthodontic treatment planning to evaluate the type of dental arch, since the space available or the space required changes depending on the arch form and on the orthodontic tooth movement.

  20. [Dental alveolar bone and dental arch remodeling in children: orthodontic diagnosis and treatments based on individual child arch development].

    PubMed

    Xiaobing, Li

    2016-12-01

    The etiology of malocclusions basically involves both congenital and environmental factors. Malocclusion is the result of the abnormal development of the orofacial complex (including tooth, dental alveolar bone, upper and lower jaws). Early orthodontic interceptive treatments involve the elimination of all congenital and environmental factors that contribute to the malformation of the orofacial complex, as well as interrupt the deviated development of the orofacial complex and the occlusion. Early orthodontic interceptive treatments mainly aim to use children's growth potential to correct abnormal developments of occlusions and orthodontically treat malocclusions more efficiently. The early orthodontic interceptive treatments include correcting the child's bad oral habits, training the abnormal functioned para-oral muscles, maintaining the normal eruptions of succeeding permanent teeth, applying interceptive treatments to the mal-developed teeth, and employing functional orthopedic treatments for abnormal growths of the upper and lower jaws. In orthodontics, correcting mal-positioned teeth is called orthodontic treatment, while rectifying the abnormal relationships of the upper and lower jaws is called functional orthopedic treatment. However, no clear definition is available as regards to the early orthodontic interceptive treatment of malocclusions caused by the deviated development of the dental alveolar bone. This new theory of "early dental alveolar bone and dental arch remodeling technique" was proposed by Professor Li Xiaobing of the Department of Pediatric Dentistry, Faculty of Pediatric Dentistry and Orthodontics in West China Hospital of Stomatology through his clinical analyses and investigation of his early orthodontic interceptive treatments. He defined the early orthodontic corrections of abnormal growth of dental alveolar bone as "remodel". The "early dental alveolar bone and dental arch remodeling theory and technique" is proved useful in

  1. Shape characteristics of equilibrium and non-equilibrium fractal clusters.

    PubMed

    Mansfield, Marc L; Douglas, Jack F

    2013-07-28

    It is often difficult in practice to discriminate between equilibrium and non-equilibrium nanoparticle or colloidal-particle clusters that form through aggregation in gas or solution phases. Scattering studies often permit the determination of an apparent fractal dimension, but both equilibrium and non-equilibrium clusters in three dimensions frequently have fractal dimensions near 2, so that it is often not possible to discriminate on the basis of this geometrical property. A survey of the anisotropy of a wide variety of polymeric structures (linear and ring random and self-avoiding random walks, percolation clusters, lattice animals, diffusion-limited aggregates, and Eden clusters) based on the principal components of both the radius of gyration and electric polarizability tensor indicates, perhaps counter-intuitively, that self-similar equilibrium clusters tend to be intrinsically anisotropic at all sizes, while non-equilibrium processes such as diffusion-limited aggregation or Eden growth tend to be isotropic in the large-mass limit, providing a potential means of discriminating these clusters experimentally if anisotropy could be determined along with the fractal dimension. Equilibrium polymer structures, such as flexible polymer chains, are normally self-similar due to the existence of only a single relevant length scale, and are thus anisotropic at all length scales, while non-equilibrium polymer structures that grow irreversibly in time eventually become isotropic if there is no difference in the average growth rates in different directions. There is apparently no proof of these general trends and little theoretical insight into what controls the universal anisotropy in equilibrium polymer structures of various kinds. This is an obvious topic of theoretical investigation, as well as a matter of practical interest. To address this general problem, we consider two experimentally accessible ratios, one between the hydrodynamic and gyration radii, the other

  2. Smackover-Norphlet stratigraphy, South Wiggins Arch, Mississippi and Alabama

    SciTech Connect

    Cagle, J.W.; Khan, M.A.

    1983-09-01

    Mesozoic rocks of the Gulf were deposited on a wide coastal plain which was punctuated transversely by major positive and negative warpings. Two of the positive elements (Sabine and Monroe uplifts) underlie giant hydrocarbon accumulations. The Wiggins arch is notable because, although the flanks are productive, the crestal area is barren. This condition has led to a paucity of well control, especially deep well control. Only three wells on the arch have penetrated the entire sedimentary sequence (20,000 ft, 6,100 m) and reached basement rock (2 granite, 1 metamorphic) dated at 300 +/- m.y. These three wells are reported to have a normal stratigraphic sequence except that the Jurassic Haynesville Formation lies on the basement, and the Buckner, Smackover, Norphlet, and Louann are missing. Careful analysis of these wells indicates the lower part of the reported Haynesville is time-correlative with the Smackover. Thus, the Smackover is not missing, but is represented by a Haynesville-like facies deposted on a block of granitic basement. This block must have been barely emergent and led to a complex set of cays during Smackover deposition. Careful analysis of seismic records indicates the proposed cays are surrounded by areas of very different reflective character. These reflections may indicate the presence of high-energy Smackover carbonate and Norphlet sand that is missing from the wells.

  3. Behaviour of Steel Arch Stabilized by a Textile Membrane

    NASA Astrophysics Data System (ADS)

    Svoboda, O.; Machacek, J.

    2015-11-01

    Behaviour of the slender steel arch supporting textile membranes in a membrane structure with respect to in-plane and out-of plane stability is investigated in the paper. In the last decades the textile membranes have been widely used to cover both common and exclusive structures due to progress in new membrane materials with eminent properties. Nevertheless, complex analysis of such membranes in interaction with steel structure (carbon/stainless steel perimeter or supporting elements) is rather demanding, even with specialized software. Laboratory model of a large membrane structure simulating a shelter roof of a concert stage was tested and the resulting stress/deflection values are presented. The model of a reasonable size was provided with prestressed membrane of PVC coated polyester fabric Ferrari® Précontraint 702S and tested under various loadings. The supporting steel structure consisted of two steel arch tubes from S355 grade steel and perimeter prestressed cables. The stability behaviour of the inner tube was the primary interest of the investigation. The SOFiSTiK software was used to analyse the structural behaviour in 3D. Numerical non-linear analysis of deflections and internal forces of the structure under symmetrical and asymmetrical loadings covers various membrane prestressing and specific boundary conditions. The numerical results are validated using test results. Finally, the preliminary recommendations for appropriate numerical modelling and stability design of the supporting structure are presented.

  4. THE EVOLUTION OF PROTOPLANETARY DISKS IN THE ARCHES CLUSTER

    SciTech Connect

    Olczak, C.; Kaczmarek, T.; Pfalzner, S.; Harfst, S.; Portegies Zwart, S.

    2012-09-10

    Most stars form in a cluster environment. These stars are initially surrounded by disks from which potentially planetary systems form. Of all cluster environments, starburst clusters are probably the most hostile for planetary systems in our Galaxy. The intense stellar radiation and extreme density favor rapid destruction of circumstellar disks via photoevaporation and stellar encounters. Evolving a virialized model of the Arches cluster in the Galactic tidal field, we investigate the effect of stellar encounters on circumstellar disks in a prototypical starburst cluster. Despite its proximity to the deep gravitational potential of the Galactic center, only a moderate fraction of members escapes to form an extended pair of tidal tails. Our simulations show that encounters destroy one-third of the circumstellar disks in the cluster core within the first 2.5 Myr of evolution, preferentially affecting the least and most massive stars. A small fraction of these events causes rapid ejection and the formation of a weaker second pair of tidal tails that is overpopulated by disk-poor stars. Two predictions arise from our study. (1) If not destroyed by photoevaporation protoplanetary disks of massive late B- and early O-type stars represent the most likely hosts of planet formation in starburst clusters. (2) Multi-epoch K- and L-band photometry of the Arches cluster would provide the kinematically selected membership sample required to detect the additional pair of disk-poor tidal tails.

  5. Pneumatic impression: Improving dental arch impression with an inflatable balloon.

    PubMed

    Gupta, Lokendra

    2016-01-01

    The purpose of this impression technique is to overcome the problem associated with restricted mouth opening in association with high arched palate by employing pneumatic impression technique using latex balloon. A stock tray was modified with auto polymerizing acrylic resin. On the modified tray, a latex balloon was attached with aid of cyanoacrylate. The outlet of the balloon was then connected to a clinical sphygmomanometer bulb with the rubber pipe for air passage which would aid in inflating the balloon. The prepared tray assembly was then equipped for recording the impression. An adequate amount of addition polysiloxane impression material, sufficient to cover the entire area of the balloon was loaded onto the tray. The balloon was then inflated with the help of a sphygmomanometer bulb which transferred the air only in one direction. On completion of setting time of the impression material, the air pressure was relieved by deflating of balloon which helped in the easy removal of the impression. The impression was subsequently removed from the oral cavity and disinfected. This novel technique was helpful for recording impression in patients presenting with restricted mouth opening and high arched palate.

  6. archAR: an archaeological augmented reality experience

    NASA Astrophysics Data System (ADS)

    Wiley, Bridgette; Schulze, Jürgen P.

    2015-03-01

    We present an application for Android phones or tablets called "archAR" that uses augmented reality as an alternative, portable way of viewing archaeological information from UCSD's Levantine Archaeology Laboratory. archAR provides a unique experience of flying through an archaeological dig site in the Levantine area and exploring the artifacts uncovered there. Using a Google Nexus tablet and Qualcomm's Vuforia API, we use an image target as a map and overlay a three-dimensional model of the dig site onto it, augmenting reality such that we are able to interact with the plotted artifacts. The user can physically move the Android device around the image target and see the dig site model from any perspective. The user can also move the device closer to the model in order to "zoom" into the view of a particular section of the model and its associated artifacts. This is especially useful, as the dig site model and the collection of artifacts are very detailed. The artifacts are plotted as points, colored by type. The user can touch the virtual points to trigger a popup information window that contains details of the artifact, such as photographs, material descriptions, and more.

  7. Variations in the superficial palmar arch of the hand.

    PubMed

    Bataineh, Ziad M; Habbal, Omar; Moqattash, Satei T

    2009-01-01

    Variations in the pattern of the hand blood supply are frequently encountered. Awareness and identification of such variations is crucial during hand surgery. Thirty formaline fixed hands of male and female cadavers were dissected. All arteries contributing to the superficial palmar arch (SPA) of the hand were verified. In addition to the frequently encountered types of SPA, three very rare cases were described. In the first case, the superficial branch of the radial artery passed superficial to the thenar muscles with a diameter larger than that of the ulnar artery. In addition to the common palmar digital artery to the second web space, it gave the princeps pollicis and radialis indicis arteries. In the second case, the SPA was formed by the ulnar artery and was completed by a small branch from the deep branch of the radial artery. The palmar digital artery to the ulnar side of the fifth finger and the common palmar digital artery to the fourth web space arose from a common trunk. In the third case, incomplete SPA was formed by the median artery which only gave the princeps pollicis and radialis indicis arteries, while the ulnar artery supplied the rest of the hand except the ulnar side of the third finger and the second web space which were supplied by the deep palmar arch. Therefore, sound knowledge of the pattern of the blood supply of the hand by various techniques is crucial to avoid possible complications during hand surgery.

  8. Open Door Laminoplasty: Creation Of A New Vertebral Arch

    PubMed Central

    Hernandez-Vicente, Javier

    2017-01-01

    Background We describe the carrying out of our open door laminoplasty technique by reproducing a posterior vertebral arch using a local originating autologous bony graft and titanium plates. Methods We designed a prospective study and present our first 16 patients. The clinical results were evaluated with the JOA score, Nurick scale and the VAS. The functional and radiological evaluation was performed with radiographs, CT and MRI, and the measurements of the dimensions of the spinal canal were carried out with the MIPAV programme ( Johns Hopkins University). All the variables were statistically analysed by means of SPSS23.0. Results After following up the cases for two years, the clinical evaluation showed, amongst other findings, a 75% improvement in the JOA score, while the radiological controls showed an appropriate range of motion (ROM) along with the stability of the construction. The rate of complete arthrodesis of the cervical neo-arch reached was approximately 92%. Conclusions Our results show that the modifications that we performed on the technique originally described have made it into a simpler, more efficacious and safer procedure, without lessening its essential objectives. PMID:28377864

  9. Reverse Distal Transverse Palmar Arch in Distal Digital Replantation.

    PubMed

    Wei, Ching-Yueh; Orozco, Oscar; Vinagre, Gustavo; Shafarenko, Mark

    2017-07-22

    Refinements in microsurgery have made distal finger replantation an established technique with high success rates and good functional and aesthetic outcomes. However, it still represents a technically demanding procedure due to the small vessel caliber and frequent lack of vessel length, requiring the use of interpositional venous grafts in some instances. We describe a new technique for anastomosis in fingertip replantation, whereby the need for venous grafts is eliminated. Applying the reverse distal transverse palmar arch technique, 11 cases of distal digital replantation were performed between January 2011 and July 2016. The described procedure was used for arterial anastomosis in 10 cases and arteriovenous shunting for venous drainage in 1 case. A retrospective case review was conducted. The technical description and clinical outcome evaluations are presented. Ten of the 11 replanted digits survived, corresponding to an overall success rate of 91%. One replant failed due to venous insufficiency. Blood transfusions were not required for any of the patients. Follow-up (range, 1.5-5 months) revealed near-normal range of motion and good aesthetic results. All of the replanted digits developed protective sensation. The average length of hospital admission was 5 days. All patients were satisfied with the results and were able to return to their previous work. The use of the reverse distal transverse palmar arch is a novel and reliable technique in distal digital replantation when an increase in vessel length is required, allowing for a tension-free arterial repair without the need for vein grafts.

  10. Building problem solving environments with the arches framework

    SciTech Connect

    Debardeleben, Nathan; Sass, Ron; Stanzione, Jr., Daniel; Ligon, Ill, Walter

    2009-01-01

    The computational problems that scientists face are rapidly escalating in size and scope. Moreover, the computer systems used to solve these problems are becoming significantly more complex than the familiar, well-understood sequential model on their desktops. While it is possible to re-train scientists to use emerging high-performance computing (HPC) models, it is much more effective to provide them with a higher-level programming environment that has been specialized to their particular domain. By fostering interaction between HPC specialists and the domain scientists, problem-solving environments (PSEs) provide a collaborative environment. A PSE environment allows scientists to focus on expressing their computational problem while the PSE and associated tools support mapping that domain-specific problem to a high-performance computing system. This article describes Arches, an object-oriented framework for building domain-specific PSEs. The framework was designed to support a wide range of problem domains and to be extensible to support very different high-performance computing targets. To demonstrate this flexibility, two PSEs have been developed from the Arches framework to solve problem in two different domains and target very different computing platforms. The Coven PSE supports parallel applications that require large-scale parallelism found in cost-effective Beowulf clusters. In contrast, RCADE targets FPGA-based reconfigurable computing and was originally designed to aid NASA Earth scientists studying satellite instrument data.

  11. Narrowing carpal arch width to increase cross-sectional area of carpal tunnel--a cadaveric study.

    PubMed

    Li, Zong-Ming; Gabra, Joseph N; Marquardt, Tamara L; Kim, Dong Hee

    2013-04-01

    Carpal tunnel morphology plays an essential role in the etiology and treatment of carpal tunnel syndrome. The purpose of this study was to observe the morphological changes of the carpal tunnel as a result of carpal arch width narrowing. It was hypothesized that carpal arch width narrowing would result in increased height and area of the carpal arch. The carpal arch width of eight cadaveric hands was narrowed by a custom apparatus and cross-sectional ultrasound images were acquired. The carpal arch height and area were quantified as the carpal arch width was narrowed. Correlation and regression analyses were performed for the carpal arch height and area with respect to the carpal arch width. The carpal tunnel became more convex as the carpal arch width was narrowed. The initial carpal arch width, height, and area were 25.7 (SD1.9) mm, 4.1 (SD0.6) mm, and 68.5 (SD14.0) mm(2), respectively. The carpal arch height and area negatively correlated with the carpal arch width, with correlation coefficients of -0.974 (SD0.018) and -0.925 (SD0.034), respectively. Linear regression analyses showed a 1mm narrowing of the carpal arch width resulted in proportional increases of 0.40 (SD0.14) mm in the carpal arch height and 4.0 (SD2.2) mm(2) in the carpal arch area. This study demonstrates that carpal arch width narrowing leads to increased carpal arch height and area, a potential mechanism to reduce the mechanical insult to the median nerve and relieve symptoms associated with carpal tunnel syndrome. Copyright © 2013 Elsevier Ltd. All rights reserved.

  12. Narrowing carpal arch width to increase cross-sectional area of carpal tunnel – a cadaveric study

    PubMed Central

    Li, Zong-Ming; Gabra, Joseph N.; Marquardt, Tamara L.; Kim, Dong Hee

    2013-01-01

    Background Carpal tunnel morphology plays an essential role in the etiology and treatment of carpal tunnel syndrome. The purpose of this study was to observe the morphological changes of the carpal tunnel as a result of carpal arch width narrowing. It was hypothesized carpal arch width narrowing would result in increased height and area of the carpal arch. Methods The carpal arch width of eight cadaveric hands was narrowed by a custom apparatus and cross-sectional ultrasound images were acquired. The carpal arch height and area were quantified as the carpal arch width was narrowed. Correlation and regression analyses were performed for the carpal arch height and area with respect to the carpal arch width. Findings The carpal tunnel became more convex as the carpal arch width was narrowed. The initial carpal arch width, height, and area were 25.7 (SD 1.9) mm, 4.1 (SD 0.6) mm, and 68.5 (SD 14.0) mm2, respectively. The carpal arch height and area negatively correlated with the carpal arch width, with correlation coefficients of −0.974 (SD 0.018) and −0.925 (SD 0.034), respectively. Linear regression analyses showed a 1 mm narrowing of the carpal arch width resulted in proportional increases of 0.40 (SD 0.14) mm in the carpal arch height and 4.0 (SD 2.2) mm2 in the carpal arch area. Interpretation This study demonstrates that carpal arch width narrowing leads to increased carpal arch height and area, a potential mechanism to reduce the mechanical insult to the median nerve and relieve symptoms associated with carpal tunnel syndrome. PMID:23583095

  13. Evolution of magnetic topology of an erupting arched laboratory magnetoplasma

    NASA Astrophysics Data System (ADS)

    Tripathi, S.; Gekelman, W. N.

    2013-12-01

    Arched magnetoplasma structures ubiquitously exist in the solar atmosphere and affect energetic phenomena such as flares and coronal mass ejections. Presence of an electrical current in such structures generates a twisted magnetic-field and the term arched magnetic flux rope (AMFR) is used for them. In the limit of low electrical current (compared to the current-threshold for the kink instability), the magnetic twist in an AMFR becomes small and it resembles the structure of an arched magnetic flux tube. However, the term arched magnetic flux rope can be used for arched magnetoplasma structures without any loss of generality. We report results on the evolution of the magnetic topology of an erupting laboratory AMFR during its eruption. The AMFR (plasma β ≈ 10-3, Lundquist number ≈ 102-105, AMFR radius/ion-gyroradius ≈ 20, B ≈ 1000 Gauss at footpoints) is created using a lanthanum hexaboride (LaB6) plasma source and it evolves in an ambient magnetoplasma produced by another LaB6 source (See Ref. [2] for details of the experiment). The eruption is triggered by gradually increasing the electrical current in the AMFR and its evolution is captured by a fast-CCD camera. The relative magnitudes of the parameters of the AMFR and the ambient magnetoplasma can be varied to simulate a variety of conditions relevant to solar eruptions. The experiment runs continuously with a 0.5 Hz repetition rate. Hence, the plasma parameters of the AMFR are recorded with a good spatiotemporal resolution (spatial-resolution/AMFR-length ≈ 10-2 - 10-3, temporal-resolution/eruption-time ≈ 10-3) using computer-controlled movable probes. The three-dimensional magnetic-field of the AMFR is directly measured using a three-axis magnetic-loop probe. The pre-eruption phase of the AMFR remains quiescent for ≈ 100 Alfven transit times and the camera images evince a persistent appearance of the AMFR during this phase. In contrast, the post-eruption phase of the AMFR is associated with

  14. 49 CFR 230.61 - Arch tubes, water bar tubes, circulators and thermic siphons.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Arch tubes, water bar tubes, circulators and... MAINTENANCE STANDARDS Boilers and Appurtenances Washing Boilers § 230.61 Arch tubes, water bar tubes... water bar tubes shall thoroughly be cleaned mechanically, washed, and inspected. Circulators and...

  15. High- compared to low-arched athletes exhibit smaller knee abduction moments in walking and running.

    PubMed

    Powell, Douglas W; Andrews, Samantha; Stickley, Cris; Williams, D S Blaise

    2016-12-01

    High- (HA) and low-arched athletes (LA) experience distinct injury patterns. These injuries are the result of the interaction of structure and biomechanics. A suggested mechanism of patellofemoral pain pertains to frontal plane knee moments which may be exaggerated in LA athletes. We hypothesize that LA athletes will exhibit greater peak knee abduction moments than high-arched athletes.

  16. Dental arch asymmetry in young healthy human subjects evaluated by Euclidean distance matrix analysis.

    PubMed

    Ferrario, V F; Sforza, C; Miani, A; Serrao, G

    1993-03-01

    Form differences between biological structures can be evaluated using several approaches. A recently proposed method (Euclidean distance matrix analysis; EDMA) seems to be able to differentiate between size and shape differences. Here it has been applied to study the asymmetry of mandibular and maxillary arches in 50 men and 45 women with sound dentitions. The centres of gravity (centroids) of the occlusal surfaces of all permanent teeth (right second molar to left second molar) were individualized on the dental casts of subjects. The form of the right and left maxillary and mandibular hemi-arches was separately assessed by calculating all the possible linear distances between pairs of teeth within arch and side. Side differences were tested by EDMA. In men, the maxillary and the mandibular arches were both symmetrical (i.e. there were no significant differences in size or shape between the left and right hemi-arches). In women, the mandibular arch was symmetrical, but in the maxillary arch the two antimeres had a significantly different shape. No size differences were found between the left and right female hemi-arches.

  17. Clinical Advantages and Limitations of Monolithic Zirconia Restorations Full Arch Implant Supported Reconstruction: Case Series

    PubMed Central

    Carames, Joao; Yu, Yung Cheng Paul; Pérez, Alejandro; Kang, Mary

    2015-01-01

    Purpose. The purpose of this retrospective case series is to evaluate the clinical advantages and limitations of monolithic zirconia restorations for full arch implant supported restorations and report the rate of complications up to 2 years after insertion. Materials and Methods. Fourteen patients received implant placement for monolithic zirconia full arch reconstructions. Four implants were placed in seven arches, eleven arches received six implants, two arches received seven implants, two arches received eight implants, and one arch received nine implants. Results. No implant failures or complications were reported for an implant survival rate of 100% with follow-up ranging from 3 to 24 months. Conclusions. Monolithic zirconia CAD-/CAM-milled framework restorations are a treatment option for full arch restorations over implants, showing a 96% success rate in the present study. Some of the benefits are accuracy, reduced veneering porcelain, and minimal occlusal adjustments. The outcome of the present study showed high success in function, aesthetics, phonetics, and high patient satisfaction. PMID:26124835

  18. Stability of clogging arches in a silo submitted to vertical vibrations

    NASA Astrophysics Data System (ADS)

    Lozano, C.; Zuriguel, I.; Garcimartín, A.

    2015-06-01

    We present experimental results on the endurance of arches that block the outlet of a two-dimensional silo when subjected to vertical vibration. In a recent paper [C. Lozano et al., Phys. Rev. Lett. 109, 068001 (2012), 10.1103/PhysRevLett.109.068001], it was shown that the arch resistance against vibrations is determined by the maximum angle among those formed between each particle in the bridge and its two neighbors: the larger the maximum angle is, the weaker the bridge. It has also been reported that the breaking time distribution shows a power-law tail with an exponent that depends on the outlet size, the vibration intensity, and the load [I. Zuriguel et al., Sci. Rep. 4, 7324 (2014), 10.1038/srep07324]. Here we connect these previous works, demonstrating the importance of the maximum angle in the arch on the exponent of the breaking time distribution. Besides, we find that the acceleration needed to break an arch does not depend on the ramp rate of the applied acceleration, but it does depend on the outlet size above which the arch is formed. We also show that high frequencies of vibration reveal a change in the behavior of the arches that endure very long times. These arches have been identified as a subset with special geometrical features. Therefore, arches that cannot be broken by means of a given external excitation might exist.

  19. Right aortic arch with aberrant left subclavian artery symptomatic in adulthood.

    PubMed

    Bashar, Abul Hasan Muhammad; Kazui, Teruhisa; Yamashita, Katsushi; Terada, Hitoshi; Washiyama, Naoki; Suzuki, Kazuchika

    2006-07-01

    Congenital malformations of the aortic arch are rarely found in adulthood. We describe three cases of right aortic arch with aberrant left subclavian artery with left-sided ligamentum arteriosum presenting in adulthood as vascular rings with symptoms of tracheal compression. Varying presentation as well as surgical strategy which was individualized according to the pathological anatomy of each case are discussed.

  20. "Roller coaster maneuver via lateral orbital approach" for reduction of isolated zygomatic arch fractures.

    PubMed

    Pilanci, Ozgur; Basaran, Karaca; Datli, Asli; Kuvat, Samet Vasfi

    2013-11-01

    Numerous techniques have been reported for the reduction of zygomatic arch fractures. In this article, we aimed to describe a technique we named as "roller coaster maneuver via lateral orbital approach" to closed reduction of the isolated-type zygomatic arch fractures. Surgical outcomes of 14 patients treated with this method were outlined.

  1. Atresia of the Aortic Arch in 4-Year-Old Child: A Clinical Case Study

    PubMed Central

    Nigro Stimato, Vittoria; Didier, Dominique; Beghetti, Maurice; Tissot, Cécile

    2015-01-01

    Atresia of the aortic arch is a rare congenital heart defect with a high mortality when associated with other intracardiac defects. Cardiac magnetic resonance (CMR) provides the exact anatomy of the aortic arch and collateral circulation and is useful to diagnose-associated aortic arch anomalies. This report describes the case of a 4-year-old child with atresia of the aortic arch, referred to our institution with the diagnosis of aortic coarctation and bicuspid aortic valve. On clinical exam, the femoral pulses were not palpable and there was a significant differential blood pressure between the upper and lower limbs. The echocardiography showed a severely stenotic bicuspid aortic valve but was limited for the exact description of the aortic arch. CMR showed absence of lumen continuity between the ascending and descending aorta distal to the left subclavian artery, extending over 5 mm, with the presence of a bend in the arch and diverticulum on either side of the zone of discontinuity, suggesting the diagnosis atresia of the aortic arch rather than coarctation or interruption. The patient benefited from a successful surgical commissurotomy of the aortic valve and reconstruction of the aortic arch with a homograft. The post-operative CMR confirmed the good surgical result. This case emphasizes the utility of CMR to provide good anatomical information to establish the exact diagnosis and the operative strategy. PMID:25853109

  2. Anteroposterior dental arch and jaw-base relationships in a population sample.

    PubMed

    Zhou, Lei; Mok, Chung-Wai; Hägg, Urban; McGrath, Colman; Bendeus, Margareta; Wu, John

    2008-11-01

    To determine the association between the anteroposterior relationship of the dental arch and the anteroposterior relationship of the jaw-base in a Chinese population sample. Orthodontic casts and lateral cephalograms were obtained from a random sample of 405 twelve-year-old Chinese children from a population survey in Hong Kong. Angle's classification was used to assess the dental arch relationship from orthodontic casts. The jaw-base relationship was assessed from the lateral cephalograms using angular (ANB angle) and linear (Wits analysis) measurements. The correlation between the anteroposterior dental arch and jaw-base relationships was assessed. The anteroposterior dental arch did coincide with the jaw-base relationships, as expressed by the ANB angle in 61%, the Wits analysis in 67%, and with both in 53%. The jaw-base relationship assessed with the Wits analysis was more significantly associated with the dental arch relationship (P < .001) than that assessed with the ANB angle (P < .01). The correlation coefficient between the ANB angle and the Wits appraisal was .65 for the combined sample, and .60, .64, and .67 for Class I, II, and III dental arch relationships. In this population, the anteroposterior relationship of the dental arch and jaw-base fail to match in at least one out of every three individuals. Linear measurement of anteroposterior jaw-base relationships is a more valid reflection of the dental arch relationship than angular measurements.

  3. Obstructive membrane in arch of aorta in a case of Shone's complex

    PubMed Central

    Sadadiwala, Divyesh H.; Soni, Kunal A.

    2015-01-01

    Shone's complex is a rare congenital heart disease consisting of multisite obstruction on the left side of the heart. The obstructive membrane in the arch of aorta is never described among these obstructions. We report echocardiographic findings in a patient with Shone's complex with the obstructive membrane in the arch of aorta. PMID:26139755

  4. [The value of ultrasonography in the diagnosis of zygomatic arch fractures].

    PubMed

    Friedrich, R E; Volkenstein, R J

    1991-01-01

    In 15 cases ultrasonograms were used to verify the result of a zygomatic fracture reduction and were correlated to conventional x-ray films. Both the pre- and postoperative ultrasonograms demonstrated all fractures of the zygomatic arch. Ultrasonographic imaging of the non-exposed bone surfaces enables the operator to monitor the reduction of zygomatic arch fractures intraoperatively, and thus optimize the treatment results.

  5. The relationship between arch height and foot length: Implications for size grading.

    PubMed

    Hill, Matthew; Naemi, Roozbeh; Branthwaite, Helen; Chockalingam, Nachiappan

    2017-03-01

    Medial longitudinal Arch Height is synonymous with classifying foot type and conversely foot function. Detailed knowledge of foot anthropometry is essential in the development of ergonomically sound footwear. Current Footwear design incorporates a direct proportionate scaling of instep dimensions with those of foot length. The objective of this paper is to investigate if a direct proportional relationship exists between human arch height parameters and foot length in subjects with normal foot posture. A healthy convenience sample of 62 volunteers was recruited to participate in this observational study. All subjects were screened for normal foot health and posture. Each subject's foot dimensions were scanned and measured using a 3D Foot Scanner. From this foot length and arch height parameters were obtained. Normalised ratios of arch height with respect to foot length were also calculated. The arch height parameters and the normalised arch ratios were used interchangeably as the dependent variables with the foot length parameters used as the independent variable for Simple Linear Regression and Correlation. Analysis of foot length measures demonstrated poor correlation with all arch height parameters. No significant relationships between arch height and foot length were found. The predictive value of the relationship was found to be poor. This holds significant implications for the current method of proportionate scaling of footwear in terms of fit and function to the midfoot region for a normative population. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Inflation/Foam/Shotcrete System for Rapid Construction of Circular Arches.

    DTIC Science & Technology

    1979-05-01

    This study analyzed, designed, and fabricated a semicircular arch structure 32 ft (9.8 m) long by 13 ft (4 m) high using the inflation/foam/ shotcrete ...system can be used to construct arch-shaped structures. Skills required to operate the foam and shotcrete equipment are consistent with those available in

  7. Lemhi Arch, a late Proterozoic and early Paleozoic landmass, central Idaho

    SciTech Connect

    Ruppel, E.T.

    1985-05-01

    The northwest-trending Lemhi arch of central Idaho first formed in late middle Proterozoic time, and as much as 4500 m (14,760 ft) of middle Proterozoic clastic rocks were eroded in later proterozoic time. The west flank of the arch was partly covered in late Proterozoic(.) and Early Cambrian time by the Wilbert Formation. On the east flank, westward-thinning marine sedimentation began with deposition of the Middle Cambrian Flathead Formation, and continued through the Late Cambrian. During Ordovician and Silurian times, the east flank of the arch was dry. The west flank was submerged in the Ordovician, and the Summerhouse Formation, Kinnikinnic Quartzite, and Saturday Mountain formation were deposited. The west flank of the arch was briefly exposed after deposition of the Saturday Mountain Formation, but was partly submerged later in the Silurian, when the Laketwon Dolomite was deposited. During the Middle and Late Devonian, deposition was renewed on the west flank of the arch, where the Jefferson formation indicates eastward transgression. The east flank was exposed until the late Devonian, when a thin sequence of the Jefferson and Three Forks Formations was deposited across the top of the arch, and marine sedimentation was continuous from the miogeocline far onto the craton. The Lemhi arch continued to influence marine deposition even after it was submerged, separating shelf deposits in southwest Montana and eastcentral Idaho from miogeoclinal deposits in central Idaho. The arch was overridden by the Medicine Lodge thrust in late Early and Late Cretaceous times.

  8. Effects of unilateral premolar extraction treatment on the dental arch forms of Class II subdivision malocclusions.

    PubMed

    Dahiya, Ginu; Masoud, Ahmed I; Viana, Grace; Obrez, Ales; Kusnoto, Budi; Evans, Carla A

    2017-08-01

    A retrospective study evaluating posttreatment symmetry in dental arch form and midlines was carried out in Class II subdivision patients treated with unilateral and bilateral maxillary premolar extractions. Using Geomagic (version 14; Geomagic, Research Triangle Park, NC) and MATLAB (version 8.4; MathWorks, Natick, Mass) software, best-fit curves expressed as quartic polynomials were generated for 13 Class II subdivisions treated with unilateral extractions and 20 treated with bilateral maxillary premolar extractions. Transverse and sagittal measurements were recorded to assess symmetry. Dental models were superimposed on constructed reference planes to generate average posttreatment arches. Statistical comparisons were performed with the significance level set at P ≤0.05. The unilateral extraction group showed significant differences in transverse arch forms between the right and left sides in the anterior, anterior-middle, and middle segments of the arch, and all regions other than the posterior segment in the sagittal dimension. Significant differences were found between groups in the anterior and anterior-middle segments of the arch transversely, the middle and middle-posterior segments sagittally, and the midline deviation relative to the midsagittal plane. Superimposed average arches showed similar results. Unilateral maxillary extraction treatment generally results in a narrower and more posteriorly displaced arch form on the extraction side, with a deviated maxillary midline toward the extraction side of the arch. Copyright © 2017 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  9. Relation of Gothic arch apex to dentist-assisted centric relation.

    PubMed

    Myers, M; Dziejma, R; Goldberg, J; Ross, R; Sharry, J

    1980-07-01

    These data suggest that the widely held belief that thumb pressure can position the mandible consistently more posterior than the position indicated by the Gothic arch apex is unfounded. Furthermore, this study provides no evidence to support the contention that the dentist-assisted jaw relation is more reproducible than the relation indicated by the Gothic arch apex.

  10. The effects of short foot exercises and arch support insoles on improvement in the medial longitudinal arch and dynamic balance of flexible flatfoot patients

    PubMed Central

    Kim, Eun-Kyung; Kim, Jin Seop

    2016-01-01

    [Purpose] The purpose of the present study is to apply short foot exercises and arch support insoles in order to improve the medial longitudinal arch of flatfoot and compare the results to identify the effects of the foregoing exercises on the dynamic balance of the feet and the lower limbs. [Subjects and Methods] Fourteen university students with flexible flatfoot were selected by conducting navicular drop tests and randomly assigned to a short foot exercise group of seven subjects and an arch support insoles group of seven subjects. The intervention in the experiment was implemented for 30 minutes per time, three times per week for five weeks in total. [Results] In inter-group comparison conducted through navicular drop tests and Y-balance tests, the short foot exercise group showed significant differences. Among intra-group comparisons, in navicular drop tests, the short foot exercise group showed significant decreases. In Y-balance tests, both the short foot exercise group and the arch support insoles group showed significant increases. [Conclusion] In the present study, it could be seen that to improve flatfoot, applying short foot exercises was more effective than applying arch support insoles in terms of medial longitudinal arch improvement and dynamic balance ability. PMID:27942135

  11. Comparative Numerical Analysis of Different Strengthening Systems of Historical Brick Arches

    NASA Astrophysics Data System (ADS)

    Zielińska, M.

    2017-05-01

    The article presents a comparative numerical analysis of various ways to strengthen historical brick arches. Five ways of strengthening brick arches with steel tie-rods have been proposed. Two of these involve the use of braces wrapped around pillars supporting the arch connected with a tie-rod; the other two ways involve the use of the tie-rods with welded metal sheets of different sizes; the latter involves the use of a tie-rod glued with the use of an epoxy adhesive. The collected data were compared with the reference model of the arch left without any interference. The results make it possible to evaluate the effectiveness of the methods by comparing displacements in the vertical and horizontal direction and stresses. The article indicates the direction of proper planning and design of the arch strengthening in brick structures in historical buildings.

  12. Aortic arch morphology and late systemic hypertension following correction of coarctation of aorta.

    PubMed

    Lashley, Daniel; Curtin, John; Malcolm, Paul; Clark, Allan; Freeman, Leisa

    2007-01-01

    To reproduce in an adult population a pediatric study that found an association between aortic arch geometry and late systemic hypertension following successful repair of aortic coarctation. Fifty-one patients with successful repair of coarctation of the aorta had blood pressure measurement at rest and during exercise. After cross-sectional imaging of the aortic arch, patients were assigned to 1 of 3 previously defined morphological categories: normal, gothic, or crenel. The degree of residual stenosis and the ratio of the height/transverse diameter of the arch (A/T ratio) were calculated. No relationship was found between arch geometry and either resting- or exercise-induced hypertension. We found the classification into 3 morphological types difficult and did not find an association between gothic arch or a high A/T ratio and hypertension.

  13. Anthropometric characteristics of the pubic arch and proper function of the defense mechanisms against hernia formation.

    PubMed

    López-Cano, M; Munhequete, E G; Hermosilla-Pérez, E; Armengol-Carrasco, M; Rodríguez-Baeza, A

    2005-03-01

    In 33 inguinal regions, we determined the anthropometric characteristics of the pubic arch and the anatomic structures of the suprainguinal space and assessed whether there is a relationship between anatomic features and function of the defense mechanisms. There was a low position of the pubic arch (pubic tubercle and interspinal line distance >75 mm) in 23 cases. The low-pubic-arch group showed a significantly longer inguinal ligament and a greater angle made by the superior border of the suprainguinal space and the inguinal ligament at its medial insertion. The position of the pubic arch correlated significantly with the diameter of the internal ring, the length of the inguinal ligament, and the angle made by the superior border of the suprainguinal space and the medial insertion of the inguinal ligament. A low pubic arch would represent an unfavorable condition for an adequate function of the anatomic defense mechanism against hernia.

  14. A shared role for sonic hedgehog signalling in patterning chondrichthyan gill arch appendages and tetrapod limbs.

    PubMed

    Gillis, J Andrew; Hall, Brian K

    2016-04-15

    Chondrichthyans (sharks, skates, rays and holocephalans) possess paired appendages that project laterally from their gill arches, known as branchial rays. This led Carl Gegenbaur to propose that paired fins (and hence tetrapod limbs) originally evolved via transformation of gill arches. Tetrapod limbs are patterned by asonic hedgehog(Shh)-expressing signalling centre known as the zone of polarising activity, which establishes the anteroposterior axis of the limb bud and maintains proliferative expansion of limb endoskeletal progenitors. Here, we use loss-of-function, label-retention and fate-mapping approaches in the little skate to demonstrate that Shh secretion from a signalling centre in the developing gill arches establishes gill arch anteroposterior polarity and maintains the proliferative expansion of branchial ray endoskeletal progenitor cells. These findings highlight striking parallels in the axial patterning mechanisms employed by chondrichthyan branchial rays and paired fins/limbs, and provide mechanistic insight into the anatomical foundation of Gegenbaur's gill arch hypothesis.

  15. Imaging a boa constrictor--the incomplete double aortic arch syndrome.

    PubMed

    Narayan, Rajeev L; Kanwar, Anubhav; Jacobi, Adam; Sanz, Javier

    2012-11-01

    Incomplete double aortic arch is a rare anomaly resulting from atresia rather than complete involution in the distal left arch resulting in a non-patent fibrous cord between the left arch and descending thoracic aorta. This anatomic anomaly may cause symptomatic vascular rings, leading to stridor, wheezing, or dysphagia, requiring surgical transection of the fibrous cord. Herein, we describe an asymptomatic 59 year-old man presenting for contrast-enhanced CT angiography to assess cardiac anatomy prior to radiofrequency ablation, who was incidentally found to have an incomplete double aortic arch with hypoplasia of the left arch segment and an aortic diverticulum. Recognition of this abnormality by imaging is important to inform both corrective surgery in symptomatic patients, as well as assist in the planning of percutaneous coronary and vascular interventions.

  16. Cretaceous and Tertiary compressional tectonics as cause of Sabine arch, eastern Texas and northwestern Louisiana

    SciTech Connect

    Jackson, M.L.W.; Laubach, S.E.

    1988-09-01

    The Sabine arch is a large (12,000 mi/sup 2/ or 31,080 km/sup 2/) low-amplitude anticline centered on the Texas-Louisiana border. A basement-cored feature formed in the Jurassic, the arch has been interpreted as (1) a Jurassic horst that persisted throughout the Cretaceous as a topographic relict of rifting, (2) a dome caused by deep-seated Cretaceous plutonism, and (3) a fold caused by regional tectonism. Using regional maps and cross sections derived from 811 well logs, they tested models of the Sabine arch origin by establishing arch movement history. Their results show that the horst and plutonic dome models do not adequately explain the cause of the Sabine arch.

  17. Longitudinal study of dental arch relationships in Australian aboriginals with reference to alternate intercuspation.

    PubMed

    Brown, T; Abbott, A H; Burgess, V B

    1987-01-01

    The patterns of age change in dental arch breadths and depths were studied longitudinally in Australian Aboriginals, 92 males and 68 females. Three types of change in relative arch dimensions were recognized: a divergent pattern in which the differences between maxillary and mandibular dimensions increased with age, a convergent pattern in which the differences decreased, and a parallel pattern in which the arch differences remained metrically stable. The feature that best distinguished the Aboriginals from Caucasian groups was the high frequency of subjects, 71% of males and 40% of females, who showed a divergent growth pattern. The association between divergent growth in arch breadths and the development of alternate intercuspation, which is characterized by an inability to occlude the teeth on both sides of the arch at the same time, is discussed.

  18. Posterior arch C-1 screw technique: a cadaveric comparison study.

    PubMed

    Moisi, Marc; Fisahn, Christian; Tkachenko, Lara; Jeyamohan, Shiveindra; Reintjes, Stephen; Grunert, Peter; Norvell, Daniel C; Tubbs, R Shane; Page, Jeni; Newell, David W; Nora, Peter; Oskouian, Rod J; Chapman, Jens

    2017-03-17

    OBJECTIVE Posterior atlantoaxial stabilization and fusion using C-1 lateral mass screw fixation has become commonly used in the treatment of instability and for reconstructive indications since its introduction by Goel and Laheri in 1994 and modification by Harms in 2001. Placement of such lateral mass screws can be challenging because of the proximity to the spinal cord, vertebral artery, an extensive venous plexus, and the C-2 nerve root, which overlies the designated starting point on the posterior center of the lateral mass. An alternative posterior access point starting on the posterior arch of C-1 could provide a C-2 nerve root-sparing starting point for screw placement, with the potential benefit of greater directional control and simpler trajectory. The authors present a cadaveric study comparing an alternative strategy (i.e., a C-1 screw with a posterior arch starting point) to the conventional strategy (i.e., using the lower lateral mass entry site), specifically assessing the safety of screw placement to preserve the C-2 nerve root. METHODS Five US-trained spine fellows instrumented 17 fresh human cadaveric heads using the Goel/Harms C-1 lateral mass (GHLM) technique on the left and the posterior arch lateral mass (PALM) technique on the right, under fluoroscopic guidance. After screw placement, a CT scan was obtained on each specimen to assess for radiographic screw placement accuracy. Four faculty spine surgeons, blinded to the surgeon who instrumented the cadaver, independently graded the quality of screw placement using a modified Upendra classification. RESULTS Of the 17 specimens, the C-2 nerve root was anatomically impinged in 13 (76.5%) of the specimens. The GHLM technique was graded Type 1 or 2, which is considered "acceptable," in 12 specimens (70.6%), and graded Type 3 or 4 ("unacceptable") in 5 specimens (29.4%). In contrast, the PALM technique had 17 (100%) of 17 graded Type 1 or 2 (p = 0.015). There were no vertebral artery injuries found

  19. Neonatal aortic arch hemodynamics and perfusion during cardiopulmonary bypass.

    PubMed

    Pekkan, Kerem; Dur, Onur; Sundareswaran, Kartik; Kanter, Kirk; Fogel, Mark; Yoganathan, Ajit; Undar, Akif

    2008-12-01

    The objective of this study is to quantify the detailed three-dimensional (3D) pulsatile hemodynamics, mechanical loading, and perfusion characteristics of a patient-specific neonatal aortic arch during cardiopulmonary bypass (CPB). The 3D cardiac magnetic resonance imaging (MRI) reconstruction of a pediatric patient with a normal aortic arch is modified based on clinical literature to represent the neonatal morphology and flow conditions. The anatomical dimensions are verified from several literature sources. The CPB is created virtually in the computer by clamping the ascending aorta and inserting the computer-aided design model of the 10 Fr tapered generic cannula. Pulsatile (130 bpm) 3D blood flow velocities and pressures are computed using the commercial computational fluid dynamics (CFD) software. Second order accurate CFD settings are validated against particle image velocimetry experiments in an earlier study with a complex cardiovascular unsteady benchmark. CFD results in this manuscript are further compared with the in vivo physiological CPB pressure waveforms and demonstrated excellent agreement. Cannula inlet flow waveforms are measured from in vivo PC-MRI and 3 kg piglet neonatal animal model physiological experiments, distributed equally between the head-neck vessels and the descending aorta. Neonatal 3D aortic hemodynamics is also compared with that of the pediatric and fetal aortic stages. Detailed 3D flow fields, blood damage, wall shear stress (WSS), pressure drop, perfusion, and hemodynamic parameters describing the pulsatile energetics are calculated for both the physiological neonatal aorta and for the CPB aorta assembly. The primary flow structure is the high-speed canulla jet flow (approximately 3.0 m/s at peak flow), which eventually stagnates at the anterior aortic arch wall and low velocity flow in the cross-clamp pouch. These structures contributed to the reduced flow pulsatility (85%), increased WSS (50%), power loss (28%), and blood

  20. A laboratory study of arched magnetic flux rope eruptions*

    NASA Astrophysics Data System (ADS)

    Tripathi, S.; Gekelman, W. N.

    2010-12-01

    Arched magnetic flux ropes (AMFRs) are arch-shaped twisted magnetic-structures that confine plasma and carry electrical current. Coronal loops and solar prominences are the main examples of AMFRs in the solar atmosphere. Solar AMFRs appear stable for long duration (several Alfven transit times) and then suddenly erupt due to occurrence of instabilities (e.g., kink instability). Solar AMFR eruptions have been frequently observed to evolve into more energetic events such as solar flares and coronal mass ejections. A laboratory plasma experiment has been constructed to simulate such eruptions in an ambient magnetized plasma. The laboratory AMFR (n ~ 1019 m-3 , Te ~ 10 eV, B ~ 1 kG, L ~ 0.5 m) is produced using an annular LaB6 cathode and an annular anode mounted on two movable shafts in a vacuum chamber (1.0 m diameter, 4.5 m long). Each AMFR electrode has an electromagnet to produce a vacuum magnetic field along the curved axis of the AMFR. The vacuum chamber has an additional plasma source and electromagnets to produce the ambient magnetized plasma (n ~ 1018 m-3, Te ~ 4 eV, B ~ 25 G). Two laser beams (1064 nm, ~0.5 J/pulse) strike movable carbon targets placed behind the orifices of the electrodes to generate controlled plasma flows from the AMFR footpoints that drives the eruption. The experiment operates with a 0.5 Hz repetition rate and is highly reproducible. Thus, time evolution of the AMFR is recorded in three-dimensions with high spatio-temporal resolutions using movable diagnostic probes. Initial results on the dramatic eruption of an arched magnetic flux rope will be presented that demonstrate outward expansion of the AMFR, release of the AMFR plasma to the background, and excitation of magnetosonic waves in the ambient plasma. Reference: S. K. P. Tripathi and W. Gekelman, Phys. Rev. Lett. 105, 075005 *Work supported by US DOE and NSF Fast camera image of a laboratory AMFR. Laser generated flows can be seen emanating from the both footpoints of the AMFR.

  1. Tuning universality far from equilibrium

    PubMed Central

    Karl, Markus; Nowak, Boris; Gasenzer, Thomas

    2013-01-01

    Possible universal dynamics of a many-body system far from thermal equilibrium are explored. A focus is set on meta-stable non-thermal states exhibiting critical properties such as self-similarity and independence of the details of how the respective state has been reached. It is proposed that universal dynamics far from equilibrium can be tuned to exhibit a dynamical transition where these critical properties change qualitatively. This is demonstrated for the case of a superfluid two-component Bose gas exhibiting different types of long-lived but non-thermal critical order. Scaling exponents controlled by the ratio of experimentally tuneable coupling parameters offer themselves as natural smoking guns. The results shed light on the wealth of universal phenomena expected to exist in the far-from-equilibrium realm. PMID:23928853

  2. Detecting temperature fluctuations at equilibrium.

    PubMed

    Dixit, Purushottam D

    2015-05-21

    The Gibbs and the Boltzmann definition of temperature agree only in the macroscopic limit. The ambiguity in identifying the equilibrium temperature of a finite-sized 'small' system exchanging energy with a bath is usually understood as a limitation of conventional statistical mechanics. We interpret this ambiguity as resulting from a stochastically fluctuating temperature coupled with the phase space variables giving rise to a broad temperature distribution. With this ansatz, we develop the equilibrium statistics and dynamics of small systems. Numerical evidence using an analytically tractable model shows that the effects of temperature fluctuations can be detected in the equilibrium and dynamical properties of the phase space of the small system. Our theory generalizes statistical mechanics to small systems relevant in biophysics and nanotechnology.

  3. The application of autologous pulmonary artery in surgical correction of complicated aortic arch anomaly

    PubMed Central

    Wen, Shusheng; Cen, Jianzheng; Chen, Jimei; Xu, Gang; He, Biaochuan; Teng, Yun

    2016-01-01

    Background In the patients with longer-segment aortic arch hypoplasia or interruption with ventricular septal defect, surgery with homograft vessel or autologous pericardial patch to augment descending aortic arch will not result in adverse reactions caused by end-to-end anastomosis. In this study, we retrospectively analyzed primary experience of surgical correction of complicated aortic arch anomaly with autologous main pulmonary artery. Methods From July 2010 to March 2016, the twenty-one cases of aortic arch complex anomalies were reconstructed with autologous main pulmonary artery. There were 5 patients with interrupted aortic arch and 16 patients with coarctation of aorta. In patients with interrupted aortic arch, anterior wall of main pulmonary artery was excised to form a conduit whose diameter varied according to the area of patient’s body surface. Both ends of the conduit were anastomosed to aortic arch and descending aorta, respectively. In other patients with coarctation of aorta, aortic arch was augmented with tailored pulmonary artery patch in oval shape. The defect of main pulmonary artery was repaired with autologous pericardial patch. Results There was only one patient died of multiple organ failure postoperatively. The other twenty patients survived without any neurologic complications. Differences of blood pressure between upper and lower limbs were not significant in all cases. During follow-up period, the echocardiography for all patients in the third, sixth, twelfth, and twenty-fourth months showed that blood flow in the descending aortic arch was fluent and there was no obvious blood pressure gradient. Conclusions Autologous main pulmonary artery can be used to repair complicated aortic arch anomalies completely without any anastomotic tension or bronchial obstruction postoperatively. This procedure is feasible and possesses predominant early and mid-term effects, and autologous main pulmonary artery can retain growth capacity during follow

  4. Association between carotid intima-media thickness and aortic arch plaques.

    PubMed

    Tessitore, Elena; Rundek, Tatjana; Jin, Zhezhen; Homma, Shunichi; Sacco, Ralph L; Di Tullio, Marco R

    2010-07-01

    Large aortic arch plaques are associated with ischemic stroke. Carotid intima-media thickness (CIMT) is a marker of subclinical atherosclerosis and a strong predictor of cardiovascular disease and stroke. The association between CIMT and aortic arch plaques has been studied in patients with strokes, but not in the general population. The aim of this study was to investigate this association in an elderly asymptomatic cohort and to assess the possibility of using CIMT to predict the presence or absence of large aortic arch plaques. Stroke-free control subjects from the Aortic Plaque and Risk of Ischemic Stroke (APRIS) study underwent transesophageal echocardiography and high-resolution B-mode ultrasound of the carotid arteries. CIMT was measured at the common carotid artery, bifurcation, and internal carotid artery. The association between CIMT and aortic arch plaques was analyzed using multivariate regression models. The positive and negative predictive values of CIMT for large (>or=4 mm) aortic arch plaques were calculated. Among 138 subjects, large aortic arch plaques were present in 35 (25.4%). Only CIMT at the bifurcation was associated with large aortic arch plaques after adjustment for atherosclerotic risk factors (P=.007). The positive and negative predictive values of CIMT for aortic arch plaque>or=4 mm at the bifurcation above the 75th percentile (>or=0.95 mm) were 42% and 80%, respectively. The negative predictive value increased to 87% when the median CIMT value (0.82 mm) was used. CIMT at the bifurcation is independently associated with aortic arch plaque>or=4 mm. Its strong negative predictive value for large plaques indicates that CIMT may be used as an initial screening test to exclude severe arch atherosclerosis in the general population. Copyright (c) 2010 American Society of Echocardiography. Published by Mosby, Inc. All rights reserved.

  5. Abnormal aortic arch morphology in Turner syndrome patients is a risk factor for hypertension.

    PubMed

    De Groote, Katya; Devos, Daniël; Van Herck, Koen; Demulier, Laurent; Buysse, Wesley; De Schepper, Jean; De Wolf, Daniël

    2015-09-01

    Hypertension in Turner syndrome (TS) is a multifactorial, highly prevalent and significant problem that warrants timely diagnosis and rigorous treatment. The objective of this study was to investigate the association between abnormal aortic arch morphology and hypertension in adult TS patients. This was a single centre retrospective study in 74 adult TS patients (age 29.41 ± 8.91 years) who underwent a routine cardiac MRI. Patients were assigned to the hypertensive group (N = 31) if blood pressure exceeded 140/90 mmHg and/or if they were treated with antihypertensive medication. Aortic arch morphology was evaluated on MRI images and initially assigned as normal (N = 54) or abnormal (N = 20), based on the curve of the transverse arch and the distance between the left common carotid-left subclavian artery. We additionally used a new more objective method to describe aortic arch abnormality in TS by determination of the relative position of the highest point of the transverse arch (AoHP). Logistic regression analysis showed that hypertension is significantly and independently associated with age, BMI and abnormal arch morphology, with a larger effect size for the new AoHP method than for the classical method. TS patients with hypertension and abnormal arch morphology more often had dilatation of the ascending aorta. There is a significant association between abnormal arch morphology and hypertension in TS patients, independent of age and BMI, and not related to other structural heart disease. We suggest that aortic arch morphology should be included in the risk stratification for hypertension in TS and propose a new quantitative method to express aortic arch morphology.

  6. Equilibrium in a Production Economy

    SciTech Connect

    Chiarolla, Maria B.; Haussmann, Ulrich G.

    2011-06-15

    Consider a closed production-consumption economy with multiple agents and multiple resources. The resources are used to produce the consumption good. The agents derive utility from holding resources as well as consuming the good produced. They aim to maximize their utility while the manager of the production facility aims to maximize profits. With the aid of a representative agent (who has a multivariable utility function) it is shown that an Arrow-Debreu equilibrium exists. In so doing we establish technical results that will be used to solve the stochastic dynamic problem (a case with infinite dimensional commodity space so the General Equilibrium Theory does not apply) elsewhere.

  7. Adiabatic evolution of plasma equilibrium

    PubMed Central

    Grad, H.; Hu, P. N.; Stevens, D. C.

    1975-01-01

    A new theory of plasma equilibrium is introduced in which adiabatic constraints are specified. This leads to a mathematically nonstandard structure, as compared to the usual equilibrium theory, in which prescription of pressure and current profiles leads to an elliptic partial differential equation. Topologically complex configurations require further generalization of the concept of adiabaticity to allow irreversible mixing of plasma and magnetic flux among islands. Matching conditions across a boundary layer at the separatrix are obtained from appropriate conservation laws. Applications are made to configurations with planned islands (as in Doublet) and accidental islands (as in Tokamaks). Two-dimensional, axially symmetric, helically symmetric, and closed line equilibria are included. PMID:16578729

  8. Chemical Principles Revisited: Using the Equilibrium Concept.

    ERIC Educational Resources Information Center

    Mickey, Charles D., Ed.

    1981-01-01

    Discusses the concept of equilibrium in chemical systems, particularly in relation to predicting the position of equilibrium, predicting spontaneity of a reaction, quantitative applications of the equilibrium constant, heterogeneous equilibrium, determination of the solubility product constant, common-ion effect, and dissolution of precipitates.…

  9. Equilibrium Principles: A Game for Students

    NASA Astrophysics Data System (ADS)

    Edmonson, Lionel J., Jr.; Lewis, Don L.

    1999-04-01

    The laboratory exercise is a game using marked sugar cubes as dice. The game emphasizes the dynamic character of equilibrium. Forward and reverse rate-constant values are used to calculate an equilibrium constant and to predict equilibrium populations. Predicted equilibrium populations are compared with experimental results.

  10. The randomized shortened dental arch study: tooth loss.

    PubMed

    Walter, M H; Weber, A; Marré, B; Gitt, I; Gerss, J; Hannak, W; Hartmann, S; Heydecke, G; Huppertz, J; Jahn, F; Ludwig, A; Mundt, T; Kern, M; Klein, V; Pospiech, P; Stumbaum, M; Wolfart, S; Wöstmann, B; Busche, E; Böning, K; Luthardt, R G

    2010-08-01

    The evidence concerning the management of shortened dental arch (SDA) cases is sparse. This multi-center study was aimed at generating data on outcomes and survival rates for two common treatments, removable dental prostheses (RDP) for molar replacement or no replacement (SDA). The hypothesis was that the treatments lead to different incidences of tooth loss. We included 215 patients with complete molar loss in one jaw. Molars were either replaced by RDP or not replaced, according to the SDA concept. First tooth loss after treatment was the primary outcome measure. This event occurred in 13 patients in the RDP group and nine patients in the SDA group. The respective Kaplan-Meier survival rates at 38 months were 0.83 (95% CI: 0.74-0.91) in the RDP group and 0.86 (95% CI: 0.78-0.95) in the SDA group, the difference being non-significant.

  11. Surgical repair of truncus arteriosus associated with interrupted aortic arch.

    PubMed

    Lacour-Gayet, François; Goldberg, Steven

    2008-01-01

    The surgical repair of truncus arteriosus associated with an interrupted aortic arch (TAC-IAA) requires performing two major procedures at the same time. Due to the small number of patients, there is nearly no surgical learning curve. The surgical technique has greatly improved since the introduction of a homograft patch enlargement of the small ascending aorta. The association with a severe truncal regurgitation is a major risk factor as well as the presence of preoperative multiple organs failure. The series published by single centers are ≪10 patients, which make statistical analysis troublesome. The mortality varies from 0% to 50%. The multicentric study published in 2006 by the Congenital Heart Surgeons Society (CHSS) reports a 68% mortality (34/50). Nevertheless, the results can be excellent in experienced centers using a modern one stage surgical technique, undertaken in the first week of life.

  12. Double arch mirror study. Part 1: Preliminary engineering report

    NASA Technical Reports Server (NTRS)

    Vukobratovich, D.; Hillman, D.

    1983-01-01

    In the proposed design, the NASA AMES 20-in double arch mirror is supported by three clamp and flexure assemblies. The mirror clamp consists of a T-shaped Invar-36 member that goes into a similarly shaped socket in the back of the mirror. The mirror socket is made oversize and contacts the clamp only along the conical surface. The clamp is preloaded by a spring washer and pulls the mirror into contact with the flexure. The clamp is then inserted into the mirror socket through a cutout, is rotated 90 deg, and is then pinned in place. Loading conditions considered in socket design are discussed as well as stress in the socket and clamp. Flexure geometry and stress are examined as well as the effects of flexure error and of mirror cell error.

  13. Dynamic postures of the transverse metacarpal arch during typing.

    PubMed

    Baker, Nancy A; Xiu, Kaihua; Moehling, Krissy; Li, Zong-Ming

    2013-12-01

    The purpose of this paper is to describe the transverse metacarpal arch (TMA) during a dynamic typing task. Static/relaxed and dynamic typing TMA were collected from 36 right-handed females with musculoskeletal discomfort using a motion capture system. While the angle of right TMA static/relaxed posture (10.1° ± 5.5°) was significantly larger than the left (8.5° ± 5.6°) (P < .05), the right dynamic posture (10.6° ± 4.3°) was not significantly different from the left (10.3° ± 5.5°) (P = .66). Within both these mean scores, there was considerable individual variation, with some subjects demonstrating very flat TMA, and some very curved. The results indicate that TMA angular postures both for static/relaxed and dynamic typing are highly variable both between individuals and between individual hands.

  14. Ortner's syndrome: Cardiovocal syndrome caused by aortic arch pseudoaneurysm.

    PubMed

    Al Kindi, Adil H; Al Kindi, Faiza A; Al Abri, Qasim S; Al Kemyani, Nasser A

    2016-10-01

    72-year-old hypertensive presented with two weeks history of left sided chest pain and hoarseness. Workup demonstrated a pseudoaneurysm in the lesser curvature of the distal aortic arch opposite the origin of the left subclavian artery from a penetrating atherosclerotic ulcer. Following a left carotid-subclavian bypass, endovascular stenting of the aorta was performed excluding the pseudoaneurysm. Patient had excellent angiographic results post-stenting. Follow up at 12 weeks demonstrated complete resolution of his symptoms and good stent position with no endo-leak. Ortner's syndrome describes vocal changes caused by cardiovascular pathology. It should be included in the differential diagnosis of patients with cardiovascular risk factors presenting with hoarseness. This case demonstrates the use of endovascular stents to treat the causative pathology with resolution of symptoms. In expert hands, it represents low risk, minimally invasive therapeutic strategy with excellent early results in patients who are high risk for open procedure.

  15. Aortic Arch Plaques and Risk of Recurrent Stroke and Death

    PubMed Central

    Di Tullio, Marco R.; Russo, Cesare; Jin, Zhezhen; Sacco, Ralph L.; Mohr, J.P.; Homma, Shunichi

    2010-01-01

    Background Aortic arch plaques are a risk factor for ischemic stroke. Although the stroke mechanism is conceivably thromboembolic, no randomized studies have evaluated the efficacy of antithrombotic therapies in preventing recurrent events. Methods and Results The relationship between arch plaques and recurrent events was studied in 516 patients with ischemic stroke, double–blindly randomized to treatment with warfarin or aspirin as part of the Patent Foramen Ovale in Cryptogenic Stroke Study (PICSS), based on the Warfarin-Aspirin Recurrent Stroke Study (WARSS). Plaque thickness and morphology was evaluated by transesophageal echocardiography. End-points were recurrent ischemic stroke or death over a 2-year follow-up. Large plaques (≥4mm) were present in 19.6% of patients, large complex plaques (those with ulcerations or mobile components) in 8.5 %. During follow-up, large plaques were associated with a significantly increased risk of events (adjusted Hazard Ratio 2.12, 95% Confidence Interval 1.04-4.32), especially those with complex morphology (HR 2.55, CI 1.10-5.89). The risk was highest among cryptogenic stroke patients, both for large plaques (HR 6.42, CI 1.62-25.46) and large-complex plaques (HR 9.50, CI 1.92-47.10). Event rates were similar in the warfarin and aspirin groups in the overall study population (16.4% vs. 15.8%; p=0.43). Conclusions In patients with stroke, and especially cryptogenic stroke, large aortic plaques remain associated with an increased risk of recurrent stroke and death at two years despite treatment with warfarin or aspirin. Complex plaque morphology confers a slight additional increase in risk. PMID:19380621

  16. [Biomechanical study on dento-alveolar arch forces].

    PubMed

    Onu, Brînduşa; Burlui, V

    2009-01-01

    This study has two major objectives. The first one is to draw attention in an original device especially conceived and designed to measure bite force; the second purpose of the study is represented by proper measurements of individual bite force during bilateral clenching for two lots of patients using this device and comparing the outcomes to those of other similar studies, in order to prove its practical utility. 62 young (20-35 years of age) healthy patients were tested: 35 fully dentured subjects in control group and 27 subjects with various single unit treated edentation, in test group. The two potentiometers from the lateral side of the device are connected to a computer which would measure, register and interpret the outcomes during three different sessions of clenching for each patient. Measured values showed that the mean maximum bilateral bite force in patients with no edentation was, in all cases, higher than in patients with single unit treated edentation for all three sessions. Because the device allows simultaneous bilateral registration of the bite force, during the same session, it is obvious that it can measure also the asymmetry between left and right dental hemi-arches. Therefore, in control group, mean values found in left side were higher (369.36N - 399.75N) than right side (352.18N - 392.15N); an opposite situation was found in test group: higher values were found in right side (313.75N - 329.43N) comparing to left side (310.54N -321.53N). The device proved to be usefull not only for measuring bite force in one region of dental arches, but it is designed to simultaneous register parameters from various regions; the values obtained in this study are similar to those reported by others authors who used more sophisticated devices, so that this simple device proves its usefulness.

  17. Jaw muscle pain and its effect on gothic arch tracings.

    PubMed

    Obrez, A; Stohler, C S

    1996-04-01

    Perceived changes in occlusion and decreased range of motion are often expressed by patients with masticatory muscle pain. The adverse loading of craniomandibular tissues that results from an inadequate maxillomandibular relationship in combination with the coexisting dysfunction is widely regarded as the cause of pain. This study was designed to test whether pain can cause significant changes in position of the mandible and therefore form the basis for any perceived changes in the maxillomandibular relationship. A second objective was to determine whether pain can cause changes in the mandibular range of motion. Five subjects who rated pain intensity on a visual analog scale were used in a single-blind, randomized, repeated-measures study design. Tonic muscle pain was induced by infusion of 5% hypertonic saline solution into the central portion of the superficial masseter muscle. Isotonic saline solution was used as a control, with subjects blinded to the type of substance given. The effect of pain on the position of the apex of the gothic arch tracing, the direction of the lateral mandibular border movements, and the mandibular range of motion was studied in a horizontal plane with minimal occlusal separation. Pain significantly affected the position of the apex of the gothic arch tracing in anterior (F = 11.46, p = 0.03) and transverse (F = 35.0, p = 0.004) directions. Similarly, pain affected the orientation of the mandibular lateral border movements (F = 12.44, p = 0.02) and their magnitude (F = 14.97, p = 0.01). All pain-induced effects proved to be reversible. The observed effect of pain can explain the perceived change of bite that is frequently noted by patients with orofacial pain. This study provided evidence of an alternative causal relationship between pain and changes in occlusal relationship and questions occlusal therapy as treatment, directed toward the elimination of the underlying cause in patients with masticatory muscle pain.

  18. THREE-DIMENSIONAL LOADING AND GROWTH OF THE ZYGOMATIC ARCH

    PubMed Central

    RAFFERTY, KATHERINE L.; HERRING, SUSAN W.; ARTESE, FLAVIA

    2010-01-01

    Summary Despite a number of previous biomechanical studies on the zygomatic arch, unanswered questions remain about its three-dimensional loading and growth. Using young miniature swine, we have for the first time recorded strains from both the medial and lateral aspects of the squamosal bone during mastication and masseter muscle stimulation. Strains from the zygomatic bone flange and zygomatic arch growth data were also obtained from the same animals. A second study on a younger group of animals examined the growth of the zygomatic flange following partial removal of the masseter. Strain data indicated that the squamosal bone is bent out-of-plane and that this pattern of loading is quite different from that of the adjacent zygomatic bone, which experiences much lower strains with little evidence of out-of-plane bending. Surprisingly, strains were higher in the zygomatic flange during contralateral chews and contralateral masseter stimulations than during ipsilateral chews/stimulations. These strains proved to arise from movement of the condyle, explaining why partial removal of the masseter had little effect on the growth of the flange. Other growth results indicated an approximately threefold greater rate of subperiosteal deposition on the lateral surface of the squamosal bone than on the zygomatic bone. This difference in growth rate is attributed to the presence of sutures that contribute to the lateral displacement of the zygomatic bone but not the squamosal bone. This explanation does not exclude the possibility that the rapid apposition on the lateral squamosal surface is regulated by the high surface strains that result from out-of-plane bending. PMID:10862722

  19. Reassessing the Dlx code: the genetic regulation of branchial arch skeletal pattern and development

    PubMed Central

    Depew, Michael J; Simpson, Carol A; Morasso, Maria; Rubenstein, John LR

    2005-01-01

    The branchial arches are meristic vertebrate structures, being metameric both between each other within the rostrocaudal series along the ventrocephalic surface of the embryonic head and within each individual arch: thus, just as each branchial arch must acquire a unique identity along the rostrocaudal axis, each structure within the proximodistal axis of an arch must also acquire a unique identity. It is believed that regional specification of metameric structures is controlled by the nested expression of related genes resulting in a regional code, a principal that is though to be demonstrated by the regulation of rostrocaudal axis development in animals exerted by the nested HOM-C/Hox homeobox genes. The nested expression pattern of the Dlx genes within the murine branchial arch ectomesenchyme has more recently led to the proposal of a Dlx code for the regional specification along the proximodistal axis of the branchial arches (i.e. it establishes intra-arch identity). This review re-examines this hypothesis, and presents new work on an allelic series of Dlx loss-of-function mouse mutants that includes various combinations of Dlx1, Dlx2, Dlx3, Dlx5 and Dlx6. Although we confirm fundamental aspects of the hypothesis, we further report a number of novel findings. First, contrary to initial reports, Dlx1, Dlx2 and Dlx1/2 heterozygotes exhibit alterations of branchial arch structures and Dlx2−/− and Dlx1/2−/− mutants have slight alterations of structures derived from the distal portions of their branchial arches. Second, we present evidence for a role for murine Dlx3 in the development of the branchial arches. Third, analysis of compound Dlx mutants reveals four grades of mandibular arch transformations and that the genetic interactions of cis first-order (e.g. Dlx5 and Dlx6), trans second-order (e.g. Dlx5 and Dlx2) and trans third-order paralogues (e.g. Dlx5 and Dlx1) result in significant and distinct morphological differences in mandibular arch development

  20. Thermodynamic theory of equilibrium fluctuations

    SciTech Connect

    Mishin, Y.

    2015-12-15

    The postulational basis of classical thermodynamics has been expanded to incorporate equilibrium fluctuations. The main additional elements of the proposed thermodynamic theory are the concept of quasi-equilibrium states, a definition of non-equilibrium entropy, a fundamental equation of state in the entropy representation, and a fluctuation postulate describing the probability distribution of macroscopic parameters of an isolated system. Although these elements introduce a statistical component that does not exist in classical thermodynamics, the logical structure of the theory is different from that of statistical mechanics and represents an expanded version of thermodynamics. Based on this theory, we present a regular procedure for calculations of equilibrium fluctuations of extensive parameters, intensive parameters and densities in systems with any number of fluctuating parameters. The proposed fluctuation formalism is demonstrated by four applications: (1) derivation of the complete set of fluctuation relations for a simple fluid in three different ensembles; (2) fluctuations in finite-reservoir systems interpolating between the canonical and micro-canonical ensembles; (3) derivation of fluctuation relations for excess properties of grain boundaries in binary solid solutions, and (4) derivation of the grain boundary width distribution for pre-melted grain boundaries in alloys. The last two applications offer an efficient fluctuation-based approach to calculations of interface excess properties and extraction of the disjoining potential in pre-melted grain boundaries. Possible future extensions of the theory are outlined.

  1. Magnetospheric equilibrium with anisotropic pressure

    SciTech Connect

    Cheng, C.Z.

    1991-07-01

    Self-consistent magnetospheric equilibrium with anisotropic pressure is obtained by employing an iterative metric method for solving the inverse equilibrium equation in an optimal flux coordinate system. A method of determining plasma parallel and perpendicular pressures from either analytic particle distribution or particle distribution measured along the satellite's path is presented. The numerical results of axisymmetric magnetospheric equilibrium including the effects of finite beta, pressure anisotropy, and boundary conditions are presented for a bi-Maxwellian particle distribution. For the isotropic pressure cases, the finite beta effect produces an outward expansion of the constant magnetic flux surfaces in relation to the dipole field lines, and along the magnetic field the toroidal ring current is maximum at the magnetic equator. The effect of pressure anisotropy is found to further expand the flux surfaces outward. Along the magnetic field lines the westward ring current can be peak away from the equator due to an eastward current contribution resulting from pressure anisotropy. As pressure anisotropy increases, the peak westward current can become more singular. The outer boundary flux surface has significant effect on the magnetospheric equilibrium. For the outer flux boundary resembling dayside compressed flux surface due to solar wind pressure, the deformation of the magnetic field can be quite different from that for the outer flux boundary resembling the tail-like surface. 23 refs., 17 figs.

  2. Understanding Thermal Equilibrium through Activities

    ERIC Educational Resources Information Center

    Pathare, Shirish; Huli, Saurabhee; Nachane, Madhura; Ladage, Savita; Pradhan, Hemachandra

    2015-01-01

    Thermal equilibrium is a basic concept in thermodynamics. In India, this concept is generally introduced at the first year of undergraduate education in physics and chemistry. In our earlier studies (Pathare and Pradhan 2011 "Proc. episteme-4 Int. Conf. to Review Research on Science Technology and Mathematics Education" pp 169-72) we…

  3. An investigation of equilibrium concepts

    NASA Technical Reports Server (NTRS)

    Prozan, R. J.

    1982-01-01

    A different approach to modeling of the thermochemistry of rocket engine combustion phenomena is presented. The methodology described is based on the hypothesis of a new variational principle applicable to compressible fluid mechanics. This hypothesis is extended to treat the thermochemical behavior of a reacting (equilibrium) gas in an open system.

  4. Understanding Thermal Equilibrium through Activities

    ERIC Educational Resources Information Center

    Pathare, Shirish; Huli, Saurabhee; Nachane, Madhura; Ladage, Savita; Pradhan, Hemachandra

    2015-01-01

    Thermal equilibrium is a basic concept in thermodynamics. In India, this concept is generally introduced at the first year of undergraduate education in physics and chemistry. In our earlier studies (Pathare and Pradhan 2011 "Proc. episteme-4 Int. Conf. to Review Research on Science Technology and Mathematics Education" pp 169-72) we…

  5. Equilibrium Distribution Functions: Another Look.

    ERIC Educational Resources Information Center

    Waite, Boyd A.

    1986-01-01

    Discusses equilibrium distribution functions and provides an alternative "derivation" that allows the student, with the help of a computer, to gain intuitive insight as to the nature of distributions in general and the precise nature of the dominance of the Boltzmann distribution. (JN)

  6. Quantifying mixing using equilibrium reactions

    NASA Astrophysics Data System (ADS)

    Wheat, Philip M.; Posner, Jonathan D.

    2009-03-01

    A method of quantifying equilibrium reactions in a microchannel using a fluorometric reaction of Fluo-4 and Ca2+ ions is presented. Under the proper conditions, equilibrium reactions can be used to quantify fluid mixing without the challenges associated with constituent mixing measures such as limited imaging spatial resolution and viewing angle coupled with three-dimensional structure. Quantitative measurements of CaCl and calcium-indicating fluorescent dye Fluo-4 mixing are measured in Y-shaped microchannels. Reactant and product concentration distributions are modeled using Green's function solutions and a numerical solution to the advection-diffusion equation. Equilibrium reactions provide for an unambiguous, quantitative measure of mixing when the reactant concentrations are greater than 100 times their dissociation constant and the diffusivities are equal. At lower concentrations and for dissimilar diffusivities, the area averaged fluorescence signal reaches a maximum before the species have interdiffused, suggesting that reactant concentrations and diffusivities must be carefully selected to provide unambiguous, quantitative mixing measures. Fluorometric equilibrium reactions work over a wide range of pH and background concentrations such that they can be used for a wide variety of fluid mixing measures including industrial or microscale flows.

  7. Concurrent fractional and equilibrium crystallisation

    NASA Astrophysics Data System (ADS)

    Sha, Lian-Kun

    2012-06-01

    This paper proposes the concept of concurrent fractional and equilibrium crystallisation (CFEC) in a multi-phase magmatic system in light of experimental results on diffusivities of elements and other species in minerals and melts. A group of equations are presented to describe how the concentrations of an element or isotope change in fractionated solid, equilibrated solid, melt, liquid, and gas phases, as well as in magma, as a function of distribution coefficients and mass fractions during the CFEC process. CFEC model is a generalised and unified formulation that is valid, not only for pure fractional crystallisation (FC) and perfect equilibrium crystallisation (EC) singly, as two of its limiting end-member cases, but also for the geologically more important process of concurrent fractional and equilibrium crystallisation. The concept that both fractional and equilibrium crystallisation can operate concurrently in a magmatic system, for a given element, among different minerals, and even within different-sized crystal grains of the very same mineral phase, is of fundamental importance in deepening our current understanding of magmatic differentiation processes. CFEC probably occurs more frequently in the natural world than either pure fractional or perfect equilibrium crystallisation alone, as a result of the interplay of varying diffusivities of elements under diverse physicochemical conditions, different residence time and growth rates of mineral phases in magmas, and varying grain sizes within each phase and among different phases. The marked systematic variations in trace element concentrations in the melts of the Bishop Tuff have long been perplexing and difficult to reconcile with existing models of differentiation. CFEC, which is able to better explain the scatter trends in a systematic way than fractional crystallisation, is considered to be the cause.

  8. The Maxillary Arch and its Relationship to Cephalometric Landmarks of Selected Malay Ethnic Group

    PubMed Central

    Thu, Khin Myo; Winn, Than; Abdullah, Nizam; Jayasinghe, J.A.P.; Chandima., G.L.

    2005-01-01

    The objectives of this study were to estimate the maxillary arch measurements, to assess the validity of Pont’s & Korkhaus’ Indices; to determine the relationship between maxillary arch form with head form; and to estimate the cephalic index (CI) of the study population. A cross-sectional study was conducted on 85 mature Malay students, 28 male students (32.98%), 57 females (67.02%) attending Teachers’ Training College. Their mean age was 23.9 yr, and Cephalic Index (CI) 86.4 (95% Confidence Interval 85.5–87.3). Arch and head dimensions were significantly larger in males than in females. CI was not significantly different between males and females. Means of anterior arch width (AAW), posterior-arch-width (PAW) and arch-length (Lu) were 35.57mm, 47.3mm and 18.01mm respectively. They were significantly different from their corresponding Indices. Correlation Coefficient between bizygomatic width and anterior-arch-width was 0.18 and was not significant in both sexes of the present population. PMID:22605945

  9. Anteroposterior spondyloschisis of atlas with bilateral cleft defect of posterior arch: a case report.

    PubMed

    Park, Jung-Soo; Eun, Jong-Pil; Lee, Hai-Ong

    2011-01-15

    case report and review of the literature. to report on a patient presenting with anteroposterior defects of the arch of the atlas with a rare type of posterior arch defect. This report includes a literature review of the hypothesis for the development of this anomaly. congenital bony defects of the atlas are uncommon. Isolated posterior clefts are the most frequent anomaly, but combined anterior and posterior defects are the least common. In particular, combined anteroposterior defects of the arch of the atlas with other types of posterior arch defects, not including type A, have not been reported. These anomalies can cause confusion, particularly in the setting of trauma when the radiologic finding may be misinterpreted as representing a fracture. we report here on a 22-year-old man with an anteroposterior defect of the atlas who complained of neck pain after a traffic accident. The computed tomography demonstrated well-corticated defects with sclerotic changes and no evidence of soft tissue swelling adjacent to the bony discontinuities, consistent with a congenital abnormality. Suspecting anteroposterior spondyloschisis, we performed only conservative treatment. the patient improved on conservative therapy without a surgical procedure. we describe combined anteroposterior defects of the arch of the atlas along with other types of posterior arch defects. Most congenital defects of the arch of the atlas are found during radiologic evaluation of neck pain after trauma. Careful diagnosis is needed for these patients to avoid confusing these defects with a fracture.

  10. Relationship between lumbar changes and modifications in the plantar arch in women with low back pain

    PubMed Central

    Borges, Cláudia dos Santos; Fernandes, Luciane Fernanda Rodrigues Martinho; Bertoncello, Dernival

    2013-01-01

    OBJECTIVE : Evaluate the probable relationship among plantar arch, lumbar curvature, and low back pain. METHODS : Fifteen healthy women were assessed taking in account personal data and anthropometric measurements, photopodoscopic evaluation of the plantar arch, and biophotogrammetric postural analysis of the patient (both using the SAPO software), as well as evaluation of lumbar pain using a Visual Analog Scale (VAS). The average age of the participants was 30.45 (±6.25) years. RESULTS : Of the feet evaluated, there were six individuals with flat feet, five with high arch, and four with normal feet. All reported algic syndrome in the lumbar spine, with the highest VAS values for the volunteers with high arch. Correlation was observed between the plantar arch and the angle of the lumbar spine (r = -0.71, p = 0.004) Conclusion: High arch was correlated with more intense algic syndrome, while there was moderate positive correlation between flat foot and increased lumbar curvature, and between high arch and lumbar correction. Level of Evidence IV. Case Series. PMID:24453656

  11. [Clinical study on endoscope-assisted repair of zygomatic arch fracture].

    PubMed

    Luo, Qi; Xiao, Wenzhi; Chen, Yong; Zhang, Li

    2016-04-01

    A study was conducted to investigate the relevant applied technique and clinical value of endoscope-assisted repair of zygomatic arch fracture. A total of 10 cases of unilateral zygomatic arch fracture and 8 cases ofunilateral zygomatic fracture were included. Reduction and fixation of the zygomatic arch in all cases were performed via asmall face incision by an endoscope. Endoscope-assisted repair allowed exposure of zygomatic arch fracture and ended the anatomy of the reset. Zygomatic arch was stabilized with titanium plates. Symmetric malar was achieved in allcases after operation. Patients did not show difficulty in opening the mouth. No chewing problems or severe complicationswere evident. This method had the advantage of hidden incision, and it did not leave scars on the face. Postoperative CT examination showed excellent reduction of zygomatic arch fracture and good fixed position of titanium plate. Endoscope-assisted repair of zygomatic arch fracture via a small face incision can be an alternative operation for zygomaticarch fracture. Patients are less traumatized. There are fewer complications. A good reduction of fracture is achieved.

  12. barx1 is necessary for ectomesenchyme proliferation and osteochondroprogenitor condensation in the zebrafish pharyngeal arches

    PubMed Central

    Sperber, Steven M.; Dawid, Igor B.

    2009-01-01

    Barx1 modulates cellular adhesion molecule expression and participates in specification of tooth-types, but little is understood of its role in patterning the pharyngeal arches. We examined barx1 expression during zebrafish craniofacial development and performed a functional analysis using morpholino oligonucleotides. Barx1 is expressed in the rhombencephalic neural crest, the pharyngeal arches, the pectoral fin buds and the gut in contrast to its paralogue barx2, which is most prominently expressed in the arch epithelium. Additionally, barx1 transient expression was observed in the posterior lateral line ganglia and developing trunk/tail. We show that Barx1 is necessary for proliferation of the arch osteochondrogenic progenitors, and that morphants exhibit diminished and dysmorphic arch cartilage elements due to reductions in chondrocyte differentiation and condensation. Attenuation of Barx1 results in lost arch expression of osteochondrogenic markers col2a1, runx2a and chondromodulin, as well as odontogenic marker dlx2b. Further, loss of barx1 positively influenced gdf5 and chordin, markers of jaw joint patterning. FGF signaling is required for maintaining barx1 expression, and that ectopic BMP4 induces expression of barx1 in the intermediate region of the second pharyngeal arch. Together, these results indicate an essential role for barx1 at early stages of chondrogenesis within the developing zebrafish viscerocranium. PMID:18590717

  13. Unusual vascular ring anomaly associated with a persistent right aortic arch in two dogs.

    PubMed

    House, A K; Summerfield, N J; German, A J; Noble, P J M; Ibarrola, P; Brockman, D J

    2005-12-01

    An unusual vascular ring anomaly consisting of a persistent right aortic arch and a left ligamentum arteriosum extending from the main pulmonary artery to an aberrant left subclavian artery and left aortic arch remnant complex was identified in a German shepherd dog and a great Dane. The left subclavian artery and left aortic arch remnant complex originated at the junction between the right distal aortic arch and the descending aorta and coursed dorsal to the oesophagus in a cranial direction. The attachment of the ligamentum arteriosum to the aberrant left subclavian artery was approximately 5 cm cranial to the point of origin of the aberrant left subclavian artery and left aortic arch remnant complex from the descending aorta in both dogs. This anomaly observed in both dogs is similar to an anomaly reported in humans, in which a persistent right aortic arch is found in conjunction with an aberrant left subclavian artery and a left aortic arch remnant (Kommerell's diverticulum). Surgical ligation and division of the left ligamentum arteriosum in both dogs, along with division of the left subclavian artery in the great Dane, resulted in resolution of clinical signs in both of the dogs in this report.

  14. Holocephalan embryos provide evidence for gill arch appendage reduction and opercular evolution in cartilaginous fishes

    PubMed Central

    Gillis, J. Andrew; Rawlinson, Kate A.; Bell, Justin; Lyon, Warrick S.; Baker, Clare V. H.; Shubin, Neil H.

    2011-01-01

    Chondrichthyans possess endoskeletal appendages called branchial rays that extend laterally from their hyoid and gill-bearing (branchial) arches. Branchial ray outgrowth, like tetrapod limb outgrowth, is maintained by Sonic hedgehog (Shh) signaling. In limbs, distal endoskeletal elements fail to form in the absence of normal Shh signaling, whereas shortened duration of Shh expression correlates with distal endoskeletal reduction in naturally variable populations. Chondrichthyans also exhibit natural variation with respect to branchial ray distribution—elasmobranchs (sharks and batoids) possess a series of ray-supported septa on their hyoid and gill arches, whereas holocephalans (chimaeras) possess a single hyoid arch ray-supported operculum. Here we show that the elongate hyoid rays of the holocephalan Callorhinchus milii grow in association with sustained Shh expression within an opercular epithelial fold, whereas Shh is only transiently expressed in the gill arches. Coincident with this transient Shh expression, branchial ray outgrowth is initiated in C. milii but is not maintained, yielding previously unrecognized vestigial gill arch branchial rays. This is in contrast to the condition seen in sharks, where sustained Shh expression corresponds to the presence of fully formed branchial rays on the hyoid and gill arches. Considered in light of current hypotheses of chondrichthyan phylogeny, our data suggest that the holocephalan operculum evolved in concert with gill arch appendage reduction by attenuation of Shh-mediated branchial ray outgrowth, and that chondrichthyan branchial rays and tetrapod limbs exhibit parallel developmental mechanisms of evolutionary reduction. PMID:21220324

  15. Laboratory study of low-β forces in arched, line-tied magnetic flux ropes

    SciTech Connect

    Myers, C. E.; Yamada, M.; Ji, H.; Yoo, J.; Jara-Almonte, J.; Fox, W.

    2016-11-04

    Here, the loss-of-equilibrium is a solar eruption mechanism whereby a sudden breakdown of the magnetohydrodynamic force balance in the Sun's corona ejects a massive burst of particles and energy into the heliosphere. Predicting a loss-of-equilibrium, which has more recently been formulated as the torus instability, relies on a detailed understanding of the various forces that hold the pre-eruption magnetic flux rope in equilibrium. Traditionally, idealized analytical force expressions are used to derive simplified eruption criteria that can be compared to solar observations and modeling. What is missing, however, is a validation that these idealized analytical force expressions can be applied to the line-tied, low-aspect-ratio conditions of the corona. In this paper, we address this shortcoming by using a laboratory experiment to study the forces that act on long-lived, arched, line-tied magnetic flux ropes. Three key force terms are evaluated over a wide range of experimental conditions: (1) the upward hoop force; (2) the downward strapping force; and (3) the downward toroidal field tension force. First, the laboratory force measurements show that, on average, the three aforementioned force terms cancel to produce a balanced line-tied equilibrium. This finding validates the laboratory force measurement techniques developed here, which were recently used to identify a dynamic toroidal field tension force that can prevent flux rope eruption. The verification of magnetic force balance also confirms the low-beta assumption that the plasma thermal pressure is negligible in these experiments. Next, the measured force terms are directly compared to corresponding analytical expressions. While the measured and analytical forces are found to be well correlated, the low-aspect-ratio, line-tied conditions in the experiment are found to both reduce the measured hoop force and increase the measured tension force with respect to analytical expectations. These two co

  16. Longitudinal evaluation of dental arch asymmetry in Class II subdivision malocclusion with 3-dimensional digital models.

    PubMed

    Veli, Ilknur; Yuksel, Burcin; Uysal, Tancan

    2014-06-01

    Class II subdivision malocclusions with their asymmetric occlusal relationships often pose treatment difficulties. The aim of this study was to evaluate the longitudinal changes of dental arch asymmetry in untreated subjects with Class II subdivision malocclusion. From 706 files from the University of Michigan Growth Study, longitudinal records of 17 untreated subjects with Class II subdivision malocclusion were included this study. Dental arch changes at 3 consecutive longitudinal intervals, defined by the cervical vertebral maturation method, were analyzed on digital dental models. The average ages of the subjects were 12.4, 15.1, and 19.1 years at the 3 time periods, respectively. Maxillary and mandibular reference lines were constructed and used for the intra-arch asymmetry measurements. The Friedman test and analysis of variance with repeated measures were used to determine dental arch asymmetries at the P <0.05 level. All subjects were found to have a type 1 Class II subdivision malocclusion characterized by distal positioning of the mandibular first molar on the Class II side. No statistically significant intra-arch asymmetry changes were found for the maxillary and mandibular dental arches in any time period. Between the baseline and the final follow-up, the data indicated decreases in maxillary and mandibular intercanine arch widths and arch lengths symmetrically. The results of this study indicate that the dental arch asymmetry in patients with Class II subdivision malocclusions did not improve or worsen with growth. Copyright © 2014 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  17. The Role of Arch Compression and Metatarsophalangeal Joint Dynamics in Modulating Plantar Fascia Strain in Running

    PubMed Central

    McDonald, Kirsty A.; Stearne, Sarah M.; Alderson, Jacqueline A.; North, Ian; Pires, Neville J.; Rubenson, Jonas

    2016-01-01

    Elastic energy returned from passive-elastic structures of the lower limb is fundamental in lowering the mechanical demand on muscles during running. The purpose of this study was to investigate the two length-modulating mechanisms of the plantar fascia, namely medial longitudinal arch compression and metatarsophalangeal joint (MPJ) excursion, and to determine how these mechanisms modulate strain, and thus elastic energy storage/return of the plantar fascia during running. Eighteen runners (9 forefoot and 9 rearfoot strike) performed three treadmill running trials; unrestricted shod, shod with restricted arch compression (via an orthotic-style insert), and barefoot. Three-dimensional motion capture and ground reaction force data were used to calculate lower limb kinematics and kinetics including MPJ angles, moments, powers and work. Estimates of plantar fascia strain due to arch compression and MPJ excursion were derived using a geometric model of the arch and a subject-specific musculoskeletal model of the plantar fascia, respectively. The plantar fascia exhibited a typical elastic stretch-shortening cycle with the majority of strain generated via arch compression. This strategy was similar in fore- and rear-foot strike runners. Restricting arch compression, and hence the elastic-spring function of the arch, was not compensated for by an increase in MPJ-derived strain. In the second half of stance the plantar fascia was found to transfer energy between the MPJ (energy absorption) and the arch (energy production during recoil). This previously unreported energy transfer mechanism reduces the strain required by the plantar fascia in generating useful positive mechanical work at the arch during running. PMID:27054319

  18. Footprint-based estimates of arch structure are confounded by body composition in adults.

    PubMed

    Wearing, Scott C; Grigg, Nicole L; Lau, Hin C; Smeathers, James E

    2012-08-01

    Previous research employing indirect measures of arch structure, such as those derived from footprints, have indicated that obesity results in a "flatter" foot type. In the absence of radiographic measures, however, definitive conclusions regarding the osseous alignment of the foot cannot be made. We determined the effect of body mass index (BMI) on radiographic and footprint-based measures of arch structure. The research was a cross-sectional study in which radiographic and footprint-based measures of foot structure were made in 30 subjects (10 males, 20 female) in addition to standard anthropometric measures of height, weight, and BMI. Multiple (univariate) regression analysis demonstrated that both BMI (β = 0.39, t(26) = 2.12, p = 0.04) and radiographic arch alignment (β = 0.51, t(26) = 3.32, p < 0.01) were significant predictors of footprint-based measures of arch height after controlling for all variables in the model (R(2) = 0.59, F(3,26) = 12.3, p < 0.01). In contrast, radiographic arch alignment was not significantly associated with BMI (β = -0.03, t(26) = -0.13, p = 0.89) when Arch Index and age were held constant (R(2) = 0.52, F(3,26) = 9.3, p < 0.01). Adult obesity does not influence osseous alignment of the medial longitudinal arch, but selectively distorts footprint-based measures of arch structure. Footprint-based measures of arch structure should be interpreted with caution when comparing groups of varying body composition.

  19. The Role of Arch Compression and Metatarsophalangeal Joint Dynamics in Modulating Plantar Fascia Strain in Running.

    PubMed

    McDonald, Kirsty A; Stearne, Sarah M; Alderson, Jacqueline A; North, Ian; Pires, Neville J; Rubenson, Jonas

    2016-01-01

    Elastic energy returned from passive-elastic structures of the lower limb is fundamental in lowering the mechanical demand on muscles during running. The purpose of this study was to investigate the two length-modulating mechanisms of the plantar fascia, namely medial longitudinal arch compression and metatarsophalangeal joint (MPJ) excursion, and to determine how these mechanisms modulate strain, and thus elastic energy storage/return of the plantar fascia during running. Eighteen runners (9 forefoot and 9 rearfoot strike) performed three treadmill running trials; unrestricted shod, shod with restricted arch compression (via an orthotic-style insert), and barefoot. Three-dimensional motion capture and ground reaction force data were used to calculate lower limb kinematics and kinetics including MPJ angles, moments, powers and work. Estimates of plantar fascia strain due to arch compression and MPJ excursion were derived using a geometric model of the arch and a subject-specific musculoskeletal model of the plantar fascia, respectively. The plantar fascia exhibited a typical elastic stretch-shortening cycle with the majority of strain generated via arch compression. This strategy was similar in fore- and rear-foot strike runners. Restricting arch compression, and hence the elastic-spring function of the arch, was not compensated for by an increase in MPJ-derived strain. In the second half of stance the plantar fascia was found to transfer energy between the MPJ (energy absorption) and the arch (energy production during recoil). This previously unreported energy transfer mechanism reduces the strain required by the plantar fascia in generating useful positive mechanical work at the arch during running.

  20. Anomalies of the fetal aortic arch: a novel sonographic approach to in-utero diagnosis.

    PubMed

    Achiron, R; Rotstein, Z; Heggesh, J; Bronshtein, M; Zimand, S; Lipitz, S; Yagel, S

    2002-12-01

    To describe a novel, sonographic approach for in-utero evaluation of normal and abnormal aortic arch. Aortic arch was evaluated by imaging of the axial view of the upper fetal mediastinum. The normal left aortic arch was defined by the V-shaped appearance of the junction between the ductus arteriosus and aortic arch, with the trachea situated posteriorly. Right and double aortic arches were diagnosed when the great vessels appeared U-shaped, with intermediate location of the trachea. Between 1997 and 1999, 18 347 women were scanned in three prenatal centers, and pathological findings were prospectively recorded. In a retrospective analysis of the records, we identified 19 fetuses (0.1%) with atypical, U-shaped appearance, and no other structural abnormalities present. With the exception of one fetus with a ventricular septal defect, no congenital cardiac defects were present. Right aortic arch was found in 18 cases, while color Doppler made it possible to diagnose one case with double aortic arch, and one fetus was demonstrated as having Kommerell's diverticulum. In all 18 cases, a left descending aorta and left ductus arteriosus were present, the latter coursing to the left of the trachea, forming a loose partial vascular ring. All were asymptomatic at birth and early infancy. The fetus with double aortic arch that had a true vascular ring underwent early infantile correction. It is possible to diagnose right and double fetal aortic arch using prenatal ultrasound. The use of color Doppler facilitated in-utero evaluation of possible complications, such as true vascular ring.