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Sample records for arch study rasda

  1. The randomized shortened dental arch study (RaSDA): design and protocol

    OpenAIRE

    Kern Matthias; Jahn Florentine; Heydecke Guido; Hartmann Sinsa; Hannak Wolfgang; Gitt Ingrid; Dressler Paul; Busche Eckhard; Aggstaller Hans; Heinecke Achim; Gerss Joachim; Marré Birgit; Luthardt Ralph G; Mundt Torsten; Pospiech Peter

    2010-01-01

    Abstract Background Various treatment options for the prosthetic treatment of jaws where all molars are lost are under discussion. Besides the placement of implants, two main treatment types can be distinguished: replacement of the missing molars with removable dental prostheses and non-replacement of the molars, i.e. preservation of the shortened dental arch. Evidence is lacking regarding the long-term outcome and the clinical performance of these approaches. High treatment costs and the lon...

  2. The randomized shortened dental arch study (RaSDA: design and protocol

    Directory of Open Access Journals (Sweden)

    Kern Matthias

    2010-02-01

    Full Text Available Abstract Background Various treatment options for the prosthetic treatment of jaws where all molars are lost are under discussion. Besides the placement of implants, two main treatment types can be distinguished: replacement of the missing molars with removable dental prostheses and non-replacement of the molars, i.e. preservation of the shortened dental arch. Evidence is lacking regarding the long-term outcome and the clinical performance of these approaches. High treatment costs and the long time required for the treatment impede respective clinical trials. Methods/design This 14-center randomized controlled investigator-initiated trial is ongoing. Last patient out will be in 2010. Patients over 35 years of age with all molars missing in one jaw and with at least both canines and one premolar left on each side were eligible. One group received a treatment with removable dental prostheses for molar replacement (treatment A. The other group received a treatment limited to the replacement of all missing anterior and premolar teeth using fixed bridges (treatment B. A pilot trial with 32 patients was carried out. Two hundred and fifteen patients were enrolled in the main trial where 109 patients were randomized for treatment A and 106 for treatment B. The primary outcome measure is further tooth loss during the 5-year follow-up. The secondary outcome measures encompassed clinical, technical and subjective variables. The study is funded by the Deutsche Forschungsgemeinschaft (German Research Foundation, DFG WA 831/2-1, 2-2, 2-3, 2-4, 2-5. Discussion The particular value of this trial is the adaptation of common design components to the very specific features of complex dental prosthetic treatments. The pilot trial proved to be indispensable because it led to a number of adjustments in the study protocol that considerably improved the practicability. The expected results are of high clinical relevance and will show the efficacy of two common

  3. HADRIAN’S ARCHES FROM ROMAN PERIOD, JORDAN: A COMPARATIVE STUDY

    OpenAIRE

    Nassar, Mohammad

    2014-01-01

    This article provides a study of Hadrian arches from three main locations: Jordan, Turkey, and Greece. Collectively within these countries, four arches have been found the Hadrian arch at Jerash (Gerasa) in Jordan, the Hadrian arch in Antalya and Ephesus, both in Turkey, and the Hadrian arch in Athens, Greece. The units of our analysis include all the different designs and plans used in constructing these arches. The analyzed design and planning units constitute a database that enables the...

  4. The Randomized Shortened Dental Arch Study: Tooth Loss

    OpenAIRE

    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.

    2010-01-01

    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 ...

  5. Correlation between arch form and facial form: A cross sectional study

    Directory of Open Access Journals (Sweden)

    Sanjna Nayar

    2015-01-01

    Full Text Available Arch form is a key determinant in teeth position. Teeth selection and placement must be based on the functional and esthetic needs of the patient. Keeping in mind, the biomechanics involved with the prosthesis. The aim of the study was to evaluate the correlation between arch form and facial form. About 40 individuals in the age group of 20-25 years were involved in the study. The arch form and facial form were analyzed statistically to check for any correlation. It was found that, 63.63% of leptoprosophic individuals had squarish arch form while, 54.6% of mesoprosophic faces had ovoid arch form.

  6. A STUDY ON SUPERFICIAL PALMAR ARCH AND IT’S VARIATIONS

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    Venkateswara Rao

    2015-03-01

    Full Text Available INTRODUCTION: Knowledge of the frequency of anatomical variations of arterial pattern of hand is crucial for safe and successful hand surgical approach, diagnostic and therapeutic procedures. The superficial pal mar arch is a major blood supply to the hand. Various ano malous patterns in the superficial arch of hand are reported. The superficial pal mar arch is formed predominantly by ulnar artery with a contribution from superficial branch of radial artery. OBSERVATIONS: Superficial palmar arch is dissected within the p alm and observed from its origin to termination. Variations in its origin, branches were observed. A classic superficial palmar arch was found in 10% [5/50]. O ut of dissected specimens complete arch found in 67% and incomplete arch was 33%. Incomplete arch is formed by ulnar artery alone. It supply four and half fingers and give five branches. Majority of arches is supplied by three and half fingers and gives four branches. DISCUSSION: Many attempts have been made to classify these variations. A complex cla ssification of superficial pal mar arch by Coleman & Anson [1961]. S ince then, many other classification have been suggested by different authors [Karlsson & N iechajev, 1982; al - Turk & Metcalf, 1984; Doscher et al. 1985; Ruengsakulrachh et al. 2001;] provi des simplest understanding of distribution of the arches. Although the classical pattern of the arch occurs in frequently, anatomical presence of a complete superficial palmar arch varies from 84% to 66% [Coleman & Anson]. This incidence was lower in the c urrent study and might be a reflection of sample size [52 hands]. The median artery was found in 10% of the hands, similar frequency to that reported by McCormack et al. [1953].

  7. Measuring medial longitudinal arch deformation during gait. A reliability study

    DEFF Research Database (Denmark)

    Bencke, Jesper; Christiansen, Ditte; Jensen, Anne Kathrine Bendrup;

    2012-01-01

    Clinical evaluation of medial longitudinal arch deformation (MLAD) during walking gait is often estimated from static measures of e.g. navicular drop (ND) measured during quiet standing. The aim of the present study was to test the reliability of a new three-dimensional method of measuring the MLAD...... during gait and to compare this method with a static measure and a 2D dynamic method. Fifty-two feet (26 healthy male participants) were tested twice 4-9 days apart in a biomechanical gait analysis laboratory using a 3D three-marker foot model, a 2D video-based model for the measurement of MLAD during...... and showed that ND obtained during quiet standing could not predict the MLAD during gait. The 3D method, or alternatively the 2D method, may be used in clinical settings as reliable methods for easy estimation of the foot longitudinal stability....

  8. The randomized shortened dental arch study: tooth loss.

    Science.gov (United States)

    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. PMID:20400723

  9. Narrowing carpal arch width to increase cross-sectional area of carpal tunnel – a cadaveric study

    Science.gov (United States)

    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

  10. Correlation between arch form and facial form: A cross sectional study

    OpenAIRE

    Sanjna Nayar; Aruna; Santhosh MR; Wasim Manzoor

    2015-01-01

    Arch form is a key determinant in teeth position. Teeth selection and placement must be based on the functional and esthetic needs of the patient. Keeping in mind, the biomechanics involved with the prosthesis. The aim of the study was to evaluate the correlation between arch form and facial form. About 40 individuals in the age group of 20-25 years were involved in the study. The arch form and facial form were analyzed statistically to check for any correlation. It was found that, 63.63% of ...

  11. Dental arch changes associated with rapid maxillary expansion: A retrospective model analysis study

    Directory of Open Access Journals (Sweden)

    Ivor M D′Souza

    2015-01-01

    regions. Results: The intercanine arch width increased by 2.9 mm, inter first premolar width increased by 3.2 mm, inter second premolar width increased by 4.6 mm, intermolar width increased by 4.4 mm, arch perimeter increased by 3.2 mm, arch length decreased by 1.8 mm from pretreatment to posttreatment. There is a strong positive correlation of arch perimeter with intercanine width (r2 = 0.99, interpremolar width (r2 = 0.99 and intermolar width (r2 = 0.98, indicating that there is a significant increase in arch perimeter with increase in arch width at the canine, premolars and molar regions. Conclusion: Findings of this study demonstrate that there was a significant increase in the intercanine, inter first premolar, inter second premolar intermolar arch width and arch perimeter from pretreatment to postexpansion, which was stable at the end of fixed mechanotherapy (PEA. There was a nonsignificant decrease in arch length from pretreatment to postexpansion that further decreased nonsignificantly from postexpansion to posttreatment.

  12. Study on real working performance and overload safety factor of high arch dam

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Considering the fact that high arch dams have problems such as complicated stress,high cost,and hazards after being damaged,this paper intends to study the effects of load,material strength,and safety analysis method on dam safety and working performance of arch dams.In this article,the effects of temperature,self weight exaction way and water loading on structure response are first discussed,and a more reasonable way of considering is then put forward.By taking into consideration the mechanical property of materials and comparing the effects of different yield criteria on overloading safety of high arch dams,this paper concludes that brittle characteristics of concrete should be fully considered when conducting safety assessment for high arch dams to avoid overestimating the bearing capacity of the dams.By comparing several typical projects,this paper works out a safety assessment system of multiple safety and relevant engineering analogical analysis methods,which is closer to the actual situation,and thus is able to assess the response of high arch dam structure in a more comprehensive way,elicit the safety coefficients in different situations,and provide a new way of considering the safety assessment of high arch dams.

  13. A Comparison Study of Stress Distribution Around Dental Implants in Three Mandibular Arch Types by Finite lement Analysis

    OpenAIRE

    Monzavi A.; Farhang Gh R

    2000-01-01

    The geometric shape of dental arch (square, tapering, ovoid) is an important factor in stress distribution pattern around dental implant. The aim of this study was to evaluate the role of arch form and the amount of bone loss (normal, moderate, high) in stress distribution around dental implant by considering different load direction. Three arch forms; square, ovoid, and tapering with three different stages of bone loss were designed. Models were divided into three-dimensional elements, which...

  14. Dental arch dimensions in the mixed dentition: a study of Brazilian children from 9 to 12 years of age

    OpenAIRE

    Fabiane Louly; Paulo Roberto Aranha Nouer; Guilherme Janson; Arnaldo Pinzan

    2011-01-01

    OBJECTIVE: This study evaluated dental arch dimensional changes of Brazilian children. MATERIAL AND METHODS: Dental casts were taken from 66 children (29 males; 37 females) with normal occlusion selected among 1,687 students from public and private schools aged 9, 10, 11 and 12 years, according to the following criteria: Class I canine and molar relationships; well-aligned upper and lower dental arches; mixed dentition; good facial symmetry; no previous orthodontic treatment. Dental arch dime...

  15. A longitudinal study of dental arch morphology in children with the syndrome of Crouzon or Apert

    NARCIS (Netherlands)

    J.H. Reitsma; P. Elmi; E.M. Ongkosuwito; P.H. Buschang; B. Prahl-Andersen

    2013-01-01

    The aim of this study was to compare changes in dental arch morphology between patients with Crouzon syndrome or Apert syndrome and controls. Children between 4 and 14 yr of age with Crouzon syndrome (n = 40) or Apert syndrome (n = 28) were compared with non-syndromic controls (n = 457) in terms of

  16. Dental arch dimensions in the mixed dentition: a study of Brazilian children from 9 to 12 years of age

    Directory of Open Access Journals (Sweden)

    Fabiane Louly

    2011-04-01

    Full Text Available OBJECTIVE: This study evaluated dental arch dimensional changes of Brazilian children. MATERIAL AND METHODS: Dental casts were taken from 66 children (29 males; 37 females with normal occlusion selected among 1,687 students from public and private schools aged 9, 10, 11 and 12 years, according to the following criteria: Class I canine and molar relationships; well-aligned upper and lower dental arches; mixed dentition; good facial symmetry; no previous orthodontic treatment. Dental arch dimensions were taken by one examiner using the Korkhaus' compass and a digital pachymeter. ANOVA test was applied to compare the arch dimensions at the different ages and the t-test was used to compare the arch dimensions of male and female subjects. Arch forms were compared by means of chi-square tests. RESULTS: Only the maxillary anterior segment length showed a statistically signifcant increase from 10 to 12 years of age. Males had a signifcantly larger maxillary depth than females at the age range evaluated. The predominant dental arch form found was elliptical. CONCLUSIONS: In the studied age range, anterior maxillary length increased from 10 to 12 years of age, males had larger maxillary depth than females and the predominant arch form was elliptical.

  17. Effect of medial arch-heel support in inserts on reducing ankle eversion: a biomechanics study

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    Yung Patrick SH

    2008-02-01

    Full Text Available Abstract Background Excessive pronation (or eversion at ankle joint in heel-toe running correlated with lower extremity overuse injuries. Orthotics and inserts are often prescribed to limit the pronation range to tackle the problem. Previous studies revealed that the effect is product-specific. This study investigated the effect of medial arch-heel support in inserts on reducing ankle eversion in standing, walking and running. Methods Thirteen pronators and 13 normal subjects participated in standing, walking and running trials in each of the following conditions: (1 barefoot, and shod condition with insert with (2 no, (3 low, (4 medium, and (5 high medial arch-heel support. Motions were captured and processed by an eight-camera motion capture system. Maximum ankle eversion was calculated by incorporating the raw coordinates of 15 anatomical positions to a self-compiled Matlab program with kinematics equations. Analysis of variance with repeated measures with post-hoc Tukey pairwise comparisons was performed on the data among the five walking conditions and the five running conditions separately. Results Results showed that the inserts with medial arch-heel support were effective in dynamics trials but not static trials. In walking, they successfully reduced the maximum eversion by 2.1 degrees in normal subjects and by 2.5–3.0 degrees in pronators. In running, the insert with low medial arch support significantly reduced maximum eversion angle by 3.6 and 3.1 degrees in normal subjects and pronators respectively. Conclusion Medial arch-heel support in inserts is effective in reducing ankle eversion in walking and running, but not in standing. In walking, there is a trend to bring the over-pronated feet of the pronators back to the normal eversion range. In running, it shows an effect to restore normal eversion range in 84% of the pronators.

  18. A protocol for classifying normal- and flat-arched foot posture for research studies using clinical and radiographic measurements

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    Menz Hylton B

    2009-07-01

    Full Text Available Abstract Background There are several clinical and radiological methods available to classify foot posture in research, however there is no clear strategy for selecting the most appropriate measurements. Therefore, the aim of this study was to develop a foot screening protocol to distinguish between participants with normal- and flat-arched feet who would then subsequently be recruited into a series of laboratory-based gait studies. Methods The foot posture of ninety-one asymptomatic young adults was assessed using two clinical measurements (normalised navicular height and arch index and four radiological measurements taken from antero-posterior and lateral x-rays (talus-second metatarsal angle, talo-navicular coverage angle, calcaneal inclination angle and calcaneal-first metatarsal angle. Normative foot posture values were taken from the literature and used to recruit participants with normal-arched feet. Data from these participants were subsequently used to define the boundary between normal- and flat-arched feet. This information was then used to recruit participants with flat-arched feet. The relationship between the clinical and radiographic measures of foot posture was also explored. Results Thirty-two participants were recruited to the normal-arched study, 31 qualified for the flat-arched study and 28 participants were classified as having neither normal- or flat-arched feet and were not suitable for either study. The values obtained from the two clinical and four radiological measurements established two clearly defined foot posture groups. Correlations among clinical and radiological measures were significant (p r = 0.24 to 0.70. Interestingly, the clinical measures were more strongly associated with the radiographic angles obtained from the lateral view. Conclusion This foot screening protocol provides a coherent strategy for researchers planning to recruit participants with normal- and flat-arched feet. However, further research is

  19. A Comparison Study of Stress Distribution Around Dental Implants in Three Mandibular Arch Types by Finite lement Analysis

    Directory of Open Access Journals (Sweden)

    Monzavi A

    2000-06-01

    Full Text Available The geometric shape of dental arch (square, tapering, ovoid is an important factor in stress distribution pattern around dental implant. The aim of this study was to evaluate the role of arch form and the amount of bone loss (normal, moderate, high in stress distribution around dental implant by considering different load direction. Three arch forms; square, ovoid, and tapering with three different stages of bone loss were designed. Models were divided into three-dimensional elements, which made 5500 nodes. The 143N load was applied at two angles (straight, oblique at the last fixture, 8mm, and 16 mm from the center of implant on l!ie cantilever. The Sap90 software was used for analyzing the stress distribution in this study. 54 different conditions were evaluated. Results showed that stress concentration changed from support toward fixture due to distally changing the load in the square and ovoid arch forms with normal bone. In the tapering arch with normal bone stress concentration was around the fixture. The amount of stress in normal tapering arch was more than physiologic extend, therefore, application of cantilever in tapering arches is not recommended.

  20. Simple Way of Recording Dental Arch Forms

    OpenAIRE

    Gupta, Shreya; 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.

  1. A Morphological Study on the Relationship between Arch Form and Craniofacial Structures in Skeletal Class I and Class III Japanese Patient

    OpenAIRE

    NARUZAWA, ROBERTA MIYOE; MINOSHIMA, YASUHIRO; KAGEYAMA, TORU; Deguchi, Toshio; KURIHARA, SABURO

    1999-01-01

    Available studies about differences among races, related to prevalence of malocclusion or morphology of head and dental arches, suggest a hypothesis that the high prevalence of skeletal Class III malocclusion in Asian ancestry populations could be correlated with a tendency toward a brachycephalic head form and larger arches widths. The purpose of the present study was to evaluate anteroposterior relationship of upper and lower jaws associated to form of dental arches, maxilla, mandible, face...

  2. Comparison of Commercially Available Arch Wires with Normal Dental Arch in a Group of Iranian Population

    OpenAIRE

    Zohreh Hedayati; Farnaz Fakhri; Vahid Moshkel Gosha

    2015-01-01

    Statement of the Problem The stability of orthodontic treatment depends on preserving the patient’s pretreatment arch form and arch size during and after treatment. Purpose This investigation was aimed to study the size and shape of Iranian mandibular dental arch and evaluate the correlation of their average dental arch with commercially available preformed rectangular nickel-titanium arch wires. Materials and Method In this study, 148 subjects were selected among students of Shiraz Universit...

  3. A longitudinal three-center study of dental arch relationship in patients with bilateral cleft lip and palate.

    NARCIS (Netherlands)

    Bartzela, T.N.; Katsaros, C.; Shaw, W.C.; Ronning, E.; Rizell, S.; Bronkhorst, E.M.; Okada, T.O.; S L Pinheiro, F.H. de; Dominguez-Gonzalez, S.; Hagberg, C.; Semb, G.; Kuijpers-Jagtman, A.M.

    2010-01-01

    OBJECTIVE: To compare and evaluate longitudinally the dental arch relationships from 4.5 to 13.5 years of age with the Bauru-BCLP Yardstick in a large sample of patients with bilateral cleft lip and palate (BCLP). DESIGN: Retrospective longitudinal intercenter outcome study. PATIENTS: Dental casts o

  4. Comparison of Commercially Available Arch Wires with Normal Dental Arch in a Group of Iranian Population

    Directory of Open Access Journals (Sweden)

    Zohreh Hedayati

    2015-06-01

    Full Text Available Statement of the Problem: The stability of orthodontic treatment depends on preserving the patient’s pretreatment arch form and arch size during and after treatment. Purpose: This investigation was aimed to study the size and shape of Iranian mandibular dental arch and evaluate the correlation of their average dental arch with commercially available preformed rectangular nickel-titanium arch wires. Materials and Method: In this study, 148 subjects were selected among students of Shiraz University of Medical Sciences. The inclusion criteria were having Angle class I in molar and canine relationships, and normal growth pattern. Intercanine and intermolar widths were measured after scanning their mandibular dental casts. Three main arch form templates; square, ovoid and tapered (Orthoform TM; 3M, Unitek, CA, USA and 12 commercially available preformed mandibular nickel-titanium arch wires were scanned. Intercanine and intermolar widths of arch wires were compared with dental arch widths of the study samples. Arch width, arch form and the most appropriate arch wire were determined for each cast. Student’s t-test was used to compare arch widths and arch depths of male and female sub-jects. Coefficient of variance was used to determine the variability of indices in the study samples. Results: Most preformed arch wires were wider than the average width of the nor-mal Iranian dental arch. The most frequent arch form in Iranian population was tapered. Inter molar width was the only statistically significant variable between males and females. Conclusion: Variation in available preformed arch wires does not entirely cover the range of diversity of the normal dental arch of our population. Narrow arc

  5. Study on Optimal Grouting Timing for Controlling Uplift Deformation of a Super High Arch Dam

    Science.gov (United States)

    Lin, Peng; Zhu, Xiaoxu; Li, Qingbin; Liu, Hongyuan; Yu, Yongjun

    2016-01-01

    A grouting model is developed for use during the grouting of the complex foundation of a super high arch dam. The purpose as to determine the optimal grouting timing and appropriate grouting pressure involved in controlling the uplift deformation of the dam. The model determines the optimal grouting time as the height of the arch dam increases with the concrete pouring, by checking the tensile stresses in the dam against standard specifications. The appropriate grouting pressures are given on the basis of the actual grouting pressures monitored during the upstream riverbed foundation grouting. An engineering procedure, applying the model, was then proposed and used during foundation grouting under the toe block of the Xiluodu super high-arch dam in south-western China. The quality of the foundation grouting was evaluated against the results from pressurized water permeability tests, acoustic wave velocity tests, elastic modulus tests and panoramic photographing of the rockmass on completion of the foundation grouting. The results indicated that the proposed grouting model can be applied to effectively reduce the uplift deformation and associated cracking risk for super high arch dams, and it can be concluded that the proposed engineering grouting procedure is a valuable tool for improving foundation grouting under the toe blocks of a super high arch dam.

  6. Study on Structure of Arched Longitudinal Beams of Deep Water Wharf

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    High-pile and beam-slab quays have been widely used after several years development. They are mature enough to be one of the most important structural types of wharves in China coastal areas. In order to accommodate large tonnage vessels, wharves should be constructed in deep water gradually. However, conventional high-pile and beam-slab structures are hard to meet the requirements of large deep-water wharf. According to arch's stress characteristics, a new type of wharf with catenary arched longitudinal beams is presented in this paper. The new wharf structure can make full use of arch's overhead crossing and reinforced concrete compression resistance, improve the interval between transverse bents greatly, and decrease underwater construction quantity. Thus, the construction cost cab be reduced. Take the third phase project of the Yangshan Deep-water Port for example, comparative analysis on catenary arched longitudinal beams and conventional longitudinal beams has been made. The result shows that with the same wharf length and width, the same loads and same longitudinal beam moment, catenary arch structure can improve the interval between bents up to 28 m, decrease the number of piles and underwater construction quantity.

  7. Wind Vibration Study of Long-span Steel Arch Structure of Beijing Capital International Airport

    Institute of Scientific and Technical Information of China (English)

    ZHOU Dai; MA Jun; ZHU Zhong-yi; LIU Jie

    2005-01-01

    The wind-induced dynamic response of long-span light-weight steel arch structure of the global transportation center (GTC) of Beijing Capital International Airport was studied. A composite technique with combination of WAWS(Weighted Amplitude Wavelet Superposition) and FFT(Fast Fourier Transformation) was introduced to simulate wind velocity time series of hundreds of spatial points simultaneously. The structural shape fac tors of wind load was obtained from wind tunnel model test. The wind vibration factor based on structural displacement response was investigated. After comparing the computational results with wind tunnel model test data, it was found out that the two results accord with each other if wind comes from 0° direction angle, but are quite different if wind comes from 180° direction angle in the area blocked off by airport terminals. The possible reasons of this difference were analyzed. Haar wavelet was used to transform and analyze wind velocity time series and structural wind-induced dynamic responses. The relationship between exciting wind loads and structural responses was studied in time and frequency domains.

  8. Earthquake response of concrete arch dams with layered rock foundation in time domain with a case study of an arch dam in Iran

    Energy Technology Data Exchange (ETDEWEB)

    Barikani, A. [Tabriz Univ., Tehran (Iran, Islamic Republic of). Dept. of Civil Engineering; Hashemiravan, M. [Varamin Azad Univ., Tehran (Iran, Islamic Republic of). Dept. of Civil Engineering

    2006-07-01

    This study examined the dynamic behaviour of an arch dam and the interactions between the dam and its layered rock foundation. The seismic response of the Amir Kabir dam located in Iran was investigated using a 3-D finite element model. The rock foundation of the dam was divided into 3 areas: high resistance rock, medium resistance rock, and low resistance rock. The hydrodynamic effects of water were modelled using an added mass method with concentrate masses in nodes of elements on the upstream face of the dam body. Earthquake response of the dam was demonstrated using a time history of displacement at the dam crest, contours of maximum tensile stresses, and maximum pressure stresses on the upstream and downstream face of the dam. The study also examined issues concerning tensile cracks that occurred as a result of an actual earthquake. Results showed that the maximum tensile stress in the upstream face of the dam was 2.5 times more than allowable limits for tensile stress in concrete. The maximum pressure stress was lower than allowable limits. A comparison between the time history of the principal stresses at different points of the dam demonstrated that maximum tensile stress occurred in the middle of the dam. However pressure was highest near the foundation level. Results showed that the tensile cracks in the dam crest area were caused by the excessive amounts of tensile stress. It was also concluded that the earthquake used in the study was in the design basis earthquake (DBE) category, with a return period of approximately 200 years. 7 refs., 5 tabs., 10 figs.

  9. Progressive changes in arch width from primary to early mixed dentition period: A longitudinal study

    Directory of Open Access Journals (Sweden)

    S Sangwan

    2011-01-01

    Full Text Available Objective: The present study was conducted to evaluate, on a longitudinal basis, the changes in intercanine and intermolar widths form the primary to the early mixed dentition periods. Materials and Methods: A total of 38 children aged 4-5 years, with normal occlusion without any proximal caries or any dental anomalies, were selected. The impressions were recorded and casts were prepared. Intercanine and intermolar widths were measured on these dental casts with the help of a digital vernier calliper. After 3 years follow-up, the impressions were recorded again and dental casts were prepared. Intercanine and intermolar widths were measured again at this stage and were compared with the baseline data using the paired t-test and the chi square test. Results: There is a significant increase in the intercanine (3.93 + 1.70 mm and intermolar width (1.49 + 1.77 mm during the transition period from primary to early mixed dentition in both the arches and both the sexes. The gender-wise comparison showed a greater increase in males than in females, but this was not statistically significant. Conclusion: A thorough knowledge of growth changes during various stages of the mixed dentition period are important for a pediatric dentist to make an accurate diagnosis and treatment planning during preventive and interceptive orthodontics.

  10. Effects of tongue volume reduction on craniofacial growth: A longitudinal study on orofacial skeletons and dental arches.

    Science.gov (United States)

    Liu, Zi-Jun; Shcherbatyy, Volodymyr; Gu, Gaoman; Perkins, Jonathan A

    2008-10-01

    The interaction between tongue size/volume and craniofacial skeletal growth is essential for understanding the mechanism of specific types of malocclusion and objectively measuring outcomes of various surgical and/or orthodontic treatments. Currently available information on this interaction is limited. This study was designed to examine how tongue body volume reduction affects craniofacial skeleton and dental arch formation during the rapid growth period in five 12-week-old Yucatan minipig sibling pairs. One of each pair received a standardized reduction glossectomy to reduce tongue volume by 15-17% (reduction group), and the other had the reduction glossectomy incisions without tissue removal (sham group). Before surgery, five stainless steel screws were implanted into standardized craniofacial skeletal locations. A series of cephalograms, lateral and axial, were obtained longitudinally at 1 week preoperative, and 2 and 4 weeks postoperative. These images were traced using superimposition, and linear and angular variables were measured digitally. Upon euthanasia, direct osteometric measurements were obtained from harvested skulls. Five en-bloc bone pieces were further cut for bone mineral examination by dual photon/energy X-ray absorptiometry (DEXA). The results indicate that: (1) while daily food consumption and weekly body weight were not significantly affected, tongue volume reduction showed an overall negative effect on the linear expansion of craniofacial skeletons; (2) premaxilla and mandibular symphysis lengths, and anterior dental arch width were significantly less in reduction than sham animals at 2 and/or 4 weeks after the surgery; (3) both premaxilla/maxilla and mandible bone mineral density and content were lower in reduction than sham animals, significantly lower in anterior mandible; (4) craniofacial skeletal and dental arch size were significantly smaller in reduction than sham animals, being most significant in the mandibular anterior length and

  11. Loss of space and dental arch length after the loss of the lower first primary molar: a longitudinal study.

    Science.gov (United States)

    Cuoghi, O A; Bertoz, F A; de Mendonca, M R; Santos, E C

    1998-01-01

    The premature loss of primary teeth may harm the normal occlusal development, although there are debates relating to the necessity of using space maintainer appliances. The aim of the study is to evaluate the changes in the dental arch perimeter and the space reduction after the premature loss of the lower first primary molar in the mixed dentition stage. The sample consists of 4 lower arch plaster models of 31 patients, within the period of pre-extraction, 6, 12 and 18 months after the lower first primary molar extraction. A reduction of space was of noted with the cuspid dislocation and the permanent incisors moving toward the space of the extraction site. It was concluded that the lower first molar primary premature loss, during the mixed dentition, implicates an immediate placement of a space maintainer.

  12. Carbon Dioxide in the Aortic Arch: Coronary Effects and Implications in a Swine Study

    International Nuclear Information System (INIS)

    Purpose: CO2 angiography is considered dangerous in the aortic arch where bubbles may cause critical cerebral and cardiac ischemia. We investigated CO2distribution, physiologic effects in the heart, methods of detection and treatments. Methods: Eight pigs had CO2and iodinated contrast arch angiograms in supine and both lateral decubitus positions. An electrocardiogram, physiologic data and cardiac ultrasound were obtained. Therapies included precordial thumps and rolls to lateral decubitus positions. Results: Supine high descending aorta CO2 injections floated retrograde up the arch during diastole and preferentially filled the right coronary artery (RCA): mean score 3.5 (of 4), in nominate artery 2.4, left coronary artery 1.2; n = 17; p = 0.0001. Aortic root injections preferentially filled the RCA when the animal was supine, left coronary in the right decubitus position, and showed a diffuse pattern in the left decubitus position. Right decubitus rolls filled both coronaries causing several lethal arrhythmias. Precordialthumps successfully cleared CO2. Ultrasound is a sensitive detector of myocardial CO2. Conclusion: Arch distribution of CO2 primarily involves the RCA. Diagnostic ultrasound detects cardiac CO2 well. Precordial thumps are an effective treatment

  13. Full arch scans: conventional versus digital impressions--an in-vitro study.

    Science.gov (United States)

    Ender, A; Mehl, A

    2011-01-01

    The digital intraoral impression has become a central part of the CAD/CAM technique. The objective of the present study was to compare the accuracy (trueness and precision) of digital impressions of the full arch with that of conventional impressions on the in-vitro model. For this purpose, a master model was acquired with a new reference scanning process, the measuring trueness of which was +/- 4.1 microm and the precision +/- 2.5 microm. On the one hand, conventional impressions and then plaster models (n = 5) were produced from this master model, and on the other hand, digital impressions were made with the Cerec AC Bluecam and the Lava COS system (each n = 5). The plaster models were also scanned with the reference scanner. The available data records were superimposed and the differences determined. The deviation from the master model defines the trueness of the impression method. The deviations of the models among one another demonstrate the precision of the method. The trueness of the impressions was 55 +/- 21.8 microm in the conventional impression group, for digital impressions with Cerec Bluecam it was 49 +/- 14.2 microm and for digital impressions with Lava COS 40.3 +/- 14.1 microm. The precision was 61.3 +/- 17.9 microm for conventional impression with Impregum, 30.9 +/- 7.1 microm for digital impression with the Cerec Bluecam and 60.1 +/- 31.3 microm for digital impression with Lava COS. These in-vitro results show that accuracy of the digital impression is similar to that of the conventional impression. These results will have to be confirmed in further clinical studies. PMID:21657122

  14. Effect of prosthetic restoration on masticatory function in patients with shortened dental arches: a multicentre study.

    Science.gov (United States)

    Fueki, K; Igarashi, Y; Maeda, Y; Baba, K; Koyano, K; Sasaki, K; Akagawa, Y; Kuboki, T; Kasugai, S; Garrett, N R

    2016-07-01

    The aim of this multicentre study was to investigate the effect of prosthetic restoration for missing posterior teeth on mastication in patients with shortened dental arches (SDAs). Partially dentate patients who had an intact teeth in anterior region and missed distal molar(s) (2-12 missing occlusal units) classified as Kennedy Class I or Class II were recruited from seven university-based dental hospitals in Japan. Of the 125 subjects who underwent baseline (pre-treatment) and follow-up/post-treatment evaluation, 53 chose no replacement of missing teeth and 72 chose treatment with removable partial dentures (n = 53) or implant-supported fixed partial dentures (n = 19). Objective masticatory performance (MP) was evaluated using a gummy jelly test. Perception of chewing ability (CA) was rated using a food intake questionnaire. In the no-treatment group, mean MP and CA scores at baseline were similar to those at follow-up evaluation (P > 0·05). In the treatment group, mean MP after treatment was significantly greater than the pre-treatment mean MP (P 0·05). In a subgroup analysis of subjects in the treatment group, subjects with lower pre-treatment CA showed a significant CA increase after treatment (P = 0·004), but those with higher pre-treatment CA showed a significant decrease in CA (P = 0·001). These results suggest that prosthetic restoration for SDAs may benefit objective masticatory performance in patients needing replacement of missing posterior teeth, but the benefit in subjective chewing ability seems to be limited in subjects with perceived impairment in chewing ability before treatment. PMID:26854877

  15. The correlation study on arch type with physical fitness, body fat and heath-carter somatotype

    Institute of Scientific and Technical Information of China (English)

    Wang Lei; Yin Shuai; Sui Yuelin; Liu Yuanyuan; Ding Wenfeng

    2015-01-01

    Objective: To explore the relationship between the arch type and physical form, physical fit-ness, body fat and somatotype. Methods:Measure and type the arch of 382 male soldier in a certain army by foot-print ratio method; Routinely detect the results of height and weight, body fat, 100 and 5 000 meters running, standing jump;According to the international heath-carter method, ten indexes were measured and the somatotype were evaluated. Results:①382 samples, flatfoot 91, accounted for 23. 6%, the foot arch index 0. 60 + 0. 21;non-flatfoot 291 , 76 . 2%, arch index 1 . 14 +0 . 22 , t=22 . 83 , P=0 . 001;②Comparing the mean of the results of height, weight, BMI, body fat percentage,100 and 5 000 meters running, standing jump of the two groups( flatfoot and non-flatfoot) samples, t-text, P>0. 05; ③Assessed by the method of heath-carter shape, flatfoot group so-matotype mean is 2. 7 (0. 7) -4. 8 (1. 3) -2. 7 (0. 9), sam is 1. 5 (0. 9);non flatfoot group somatotype mean is 2. 3 (0. 7) -5. 0 (3. 1) -2. 4 (0. 9), sam is 1. 6 (1. 0);The distance of two groups`points in 3D space mean somatotypes is 0. 54; t-test of the two groups`somatotype mean, P>0. 05. Conclusions: Compared the flatfoot group with the control group, there is no significant difference in physical form, physical fitness, body fat and so-matotype. The increasingly high rate of flatfoot in healthy people is physical, but not flatfoot disease, and no need for surgery.

  16. Variations among the primary maxillary dental arch forms using a polynominal equation model.

    Science.gov (United States)

    Tsai, Hung-Huey

    2003-01-01

    This study identifies arch symmetry and describes arch form variations in normal primary maxillary dental casts. Sixty-two percent of casts had asymmetrical arches, and 38% had symmetrical arches. Six types of arch form were identified according to the ratio of arch width to length. There were more long types than short types. The rounded and short types tended to have a more-symmetrical arch than did the long type. PMID:12739689

  17. The ARCHES Project

    Science.gov (United States)

    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/

  18. Experimental Study on Cracking, Reinforcement, and Overall Stability of the Xiaowan Super-High Arch Dam

    Science.gov (United States)

    Lin, Peng; Zhou, Weiyuan; Liu, Hongyuan

    2015-03-01

    The Xiaowan super-high arch dam has faced challenging construction problems. Here, we provide a scientifically-based reference for applying geomechanical model testing to support the nonlinear design of super-high arch dams. We applied experimental similarity theory and techniques. Based on four 3D geomechanical model tests, the dam stress characteristics, deformation distribution, and the safety factors of the dam foundation were identified and compared. We also analyzed cracking characteristics of the up- and downstream dam surfaces and induced joints in the dam heel, the rock mass failure process of the dam-foundation interface, and the abutments. We propose foundation reinforcement measures for weak rock masses, alteration zones, and other faults in the abutments based on the 3D and plane tests each at a different elevation. The results show that all dam deformations remained normal with no yielding or tensile cracking under a normal water load. The reinforced rock mass increased the crack initial safety in the dam heel and toe by ~20 %. The minimum crack initial safety factor ( K 1) of the dam heel was 1.4. The induced joint in the dam heel contributed to a reduction in tensile stress at the upstream dam heel, improving K 1. Compared with similar projects following reinforcement measures, the abutment stiffness and overall stability of the Xiaowan arch dam satisfy operational requirements. Four years of monitoring operations show that key areas near the dam remained normal and the dam foundation is functioning well. Our results may also be applicable to the design and construction of similar projects worldwide.

  19. Computational Study of Non-Physiological Hemodynamics in the Cephalic Arch

    Science.gov (United States)

    Cassel, Kevin; Boghosian, Michael; Mahmoudzadeh, S. M. Javid; Hammes, Mary

    2012-11-01

    Numerical simulations of the unsteady, two-dimensional, incompressible Navier-Stokes equations are performed for the flow in a two-dimensional geometry created from radiological images and Doppler flow measurements of the cephalic arch in dialysis patients with a brachiocephalic fistula (surgically placed direct arterial-venous connection). The simulations are performed before insertion of the fistula and at subsequent time intervals as the cephalic vein arterializes over a period of three to six months. A mature fistula, with increased diameter and flow rate, can exhibit Reynolds numbers that are more than one order of magnitude larger than that of the pre-fistula vein. We evaluate the effect of this increased (physiologically abnormal) Reynolds number on flow structures and wall shear stresses through the curved cephalic arch, which is a site prone to stenosis in fistula patients. The long-term goal is to investigate if the development of initimal hyperplasia and stenoses correlates with wall shear stresses or other hemodynamic variables obtained using computational hemodynamics. Research supported by the National Institute of Diabetes And Digestive And Kidney Diseases of the National Institutes of Health under Award Number R01DK090769.

  20. The ARCHES project

    CERN Document Server

    Motch, C; Genova, F; Esteban, F Jiménez-; López, M; Michel, L; Mingo, B; Mints, A; Gómez-Morán, A Nebot; Pineau, F -X; Rosen, S; Sanchez, E; Schwope, A; Solano, E; Watson, M

    2016-01-01

    ARCHES (Astronomical Resource Cross-matching for High Energy Studies) is a FP7-Space funded project whose aim is to 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 DR5 X-ray catalogue of serendipitous sources. The project has developed new tools implementing fully probabilistic simultaneous cross-correlation of several catalogues for unresolved sources and a multi-wavelength finder for clusters of galaxies for extended sources. These enhanced resources have been tested in the framework of several science cases.

  1. Structure and distribution of arches in shaken hard sphere deposits

    OpenAIRE

    Pugnaloni, Luis A.; Barker, G. C.

    2003-01-01

    We investigate the structure and distribution of arches formed by spherical, hard particles shaken in an external field after they come to rest. Arches (or bridges) are formed during a computer-simulated, non-sequential deposition of the spheres after each shaking cycle. We identify these arches by means of a connectivity criterion and study their structural characteristics and spatial distribution. We find that neither the size distribution nor the shape of the arches is strongly affected by...

  2. Aortic arch malformations

    Energy Technology Data Exchange (ETDEWEB)

    Kellenberger, Christian J. [University Children' s Hospital, Department of Diagnostic Imaging, Zuerich (Switzerland)

    2010-06-15

    Although anomalies of the aortic arch and its branches are relatively uncommon malformations, they are often associated with congenital heart disease. Isolated lesions may be clinically significant when the airways are compromised by a vascular ring. In this article, the development and imaging appearance of the aortic arch system and its various malformations are reviewed. (orig.)

  3. Study on multi-scheme analysis and evaluation method for concrete sequence placement of high arch dam

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    A complete scheme for solving the key scientific problems of how to make concrete sequence placement scheme of high arch dam reasonable and feasible and how to meet the need of construction process was presented.First,based on a coupling analysis of concrete sequence placement system of high arch dam,a mathematical model considering complex construction constraints was established.Second,a multi-scheme computational analysis method for concrete sequence placement of high arch dam was proposed based on dynamic simulation.Third,a multi-scheme evaluation method for concrete sequence placement was put forward based on analytic hierarchy process.Fourth,feedback guidance for progress control and management in the high arch dam construction process was proposed.Finally,these methods were applied to a practical project to show that the methods can analyze and evaluate multi-scheme for concrete sequence placement of high arch dam effectively,optimize the process of dam concrete sequence placement,and recommend engineering measures.These methods provide new theoretical principles and technical measures for real-time progress control in the high arch dam construction.

  4. Nonlinear Dynamics of Electrostatically Actuated MEMS Arches

    KAUST Repository

    Al Hennawi, Qais M.

    2015-05-01

    In this thesis, we present theoretical and experimental investigation into the nonlinear statics and dynamics of clamped-clamped in-plane MEMS arches when excited by an electrostatic force. Theoretically, we first solve the equation of motion using a multi- mode Galarkin Reduced Order Model (ROM). We investigate the static response of the arch experimentally where we show several jumps due to the snap-through instability. Experimentally, a case study of in-plane silicon micromachined arch is studied and its mechanical behavior is measured using optical techniques. We develop an algorithm to extract various parameters that are needed to model the arch, such as the induced axial force, the modulus of elasticity, and the initially induced initial rise. After that, we excite the arch by a DC electrostatic force superimposed to an AC harmonic load. A softening spring behavior is observed when the excitation is close to the first resonance frequency due to the quadratic nonlinearity coming from the arch geometry and the electrostatic force. Also, a hardening spring behavior is observed when the excitation is close to the third (second symmetric) resonance frequency due to the cubic nonlinearity coming from mid-plane stretching. Then, we excite the arch by an electric load of two AC frequency components, where we report a combination resonance of the summed type. Agreement is reported among the theoretical and experimental work.

  5. A Study on the Effect of Exit Widths and Crowd Sizes in the Formation of Arch in Clogged Crowds

    CERN Document Server

    Castro, Francisco Enrique Vicente G

    2015-01-01

    The arching phenomenon is an emergent pattern formed by a $c$-sized crowd of intelligent, goal-oriented, autonomous, heterogeneous individuals moving towards a $w$-wide exit along a long $W$-wide corridor, where $W>w$. We collected empirical data from microsimulations to identify the combination effects of~$c$ and~$w$ to the time~$T$ of the onset of and the size~$S$ of the formation of the arch. The arch takes on the form of the perimeter of a half ellipse halved along the minor axis. We measured the~$S$ with respect to the lengths of the major~$M$ and minor~$m$ axes of the ellipse, respectively. The mathematical description of the formation of this phenomenon will be an important information in the design of walkways to control and easily direct the flow of large crowds, especially during panic egress conditions.

  6. Key Techniques and Risk Management for the Application of the Pile-Beam-Arch (PBA) Excavation Method: A Case Study of the Zhongjie Subway Station

    OpenAIRE

    Yong-ping Guan; Wen Zhao; Shen-gang Li; Guo-bin Zhang

    2014-01-01

    The design and construction of shallow-buried tunnels in densely populated urban areas involve many challenges. The ground movements induced by tunneling effects pose potential risks to infrastructure such as surface buildings, pipelines, and roads. In this paper, a case study of the Zhongjie subway station located in Shenyang, China, is examined to investigate the key construction techniques and the influence of the Pile-Beam-Arch (PBA) excavation method on the surrounding environment. This ...

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

    Science.gov (United States)

    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. PMID:15470349

  8. Arch Index: An Easier Approach for Arch Height (A Regression Analysis

    Directory of Open Access Journals (Sweden)

    Hironmoy Roy

    2012-04-01

    Full Text Available Background: Arch-height estimation though practiced usually in supine posture; is neither correct nor scientific as referred in literature, which favour for standing x-rays or arch-index as yardstick. In fact the standing x-rays can be excused for being troublesome in busy OPD, but an ink-footprint on simple graph-sheet can be documented, as it is easier, cheaper and requires almost no machineries and expertisation. Objective: So this study aimed to redefine the inter-relationship of the radiological standing arch-heights with the arch-index for correlation and regression so that from the later we can derive the radiographical standing arch-height values indirectly, avoiding the actual maneuver. Methods: The study involved 103 adult subjects attending at a tertiary care hospital of North Bengal. From the standing x-rays of foot, the standing navicular, talar heights were measured, and ‘normalised’ with the foot length. In parallel foot-prints also been obtained for arch-index. Finally variables analysed by SPSS software. Result: The arch-index showed significant negative correlations and simple linear regressions with standing navicular height, standing talar height as well as standing normalised navicular and talar heights analysed in both sexes separately with supporting mathematical equations. Conclusion: To measure the standing arch-height in a busy OPD, it is wise to have the foot-print first. Arch-index once get known, can be put in the equations as derived here, to predict the preferred standing arch-heights in either sex.

  9. Progressive changes in arch width from primary to early mixed dentition period: A longitudinal study

    OpenAIRE

    S Sangwan; Chawla, H S.; Goyal, A.; Gauba, K.; Mohanty, U.

    2011-01-01

    Objective: The present study was conducted to evaluate, on a longitudinal basis, the changes in intercanine and intermolar widths form the primary to the early mixed dentition periods. Materials and Methods: A total of 38 children aged 4-5 years, with normal occlusion without any proximal caries or any dental anomalies, were selected. The impressions were recorded and casts were prepared. Intercanine and intermolar widths were measured on these dental casts with the help of a digital vernier ...

  10. Glossary to ARCH (GARCH)

    DEFF Research Database (Denmark)

    Bollerslev, Tim

    The literature on modeling and forecasting time-varying volatility is ripe with acronyms and abbreviations used to describe the many different parametric models that have been put forth since the original linear ARCH model introduced in the seminal Nobel Prize winning paper by Engle (1982......).  The present paper provides an easy-to-use encyclopedic reference guide to this long list of ARCH acronyms.  In addition to the acronyms associated with specific parametric models, I have also included descriptions of various abbreviations associated with more general statistical procedures and ideas...

  11. Dental Arch Dimension of Malay Ethnic Group

    Directory of Open Access Journals (Sweden)

    H. A. Mohammad

    2011-01-01

    Full Text Available Problem statement: Many previous studies tried to define and put specific measurements for dental arches dimension in different ethnics groups. However, these studies may be specific to an ethnic group and cannot always be applied to other ethnic types. The aim of this study: is to obtain specific dental arch dimensions for Malaysian Malay ethnic groups and compare between both genders. Approach: Involved clinical examination, collection and analysis of 60 dental cast of Malaysian Malay subjects from pure ethnic group (30 males and 30 females, 20-24 years old. All dental landmarks were located and determined and subsequently measurements had been done according to specific points have been selected. Statistical analysis were done using t-test. Results: Dental arch dimension were established in normal occlusion for Malaysian Malay ethnic group in this study. No significant difference was observed in arch dimensions between male and female of Malaysian Malay. Conclusion: These measurement should be considered during treatment, especially in prosthodontics and orthodontics where arch dimension can be modified appreciably.

  12. An Electrostatically Actuated MEMS Arch Band-Pass Filter

    Directory of Open Access Journals (Sweden)

    Hassen M. Ouakad

    2013-01-01

    Full Text Available This work presents an investigation of the dynamics of micromachined arches resonators and their potential to be utilized as band-pass filters. The arches are actuated by a DC electrostatic load superimposed to an AC harmonic load. The dynamic response of the arch is studied analytically using a Galerkin-based reduced-order model when excited near its fundamental and third natural frequencies. Several simulation results are presented demonstrating interesting jumps and snap-through behavior of the arches and their attractive features for uses as band-pass filters, such as their sharp roll-off from pass bands to stop bands and their flat response.

  13. A comparative study between China and U.S. on seismic design philosophy and practice of a long span arch bridge

    Institute of Scientific and Technical Information of China (English)

    Xu Yan; George C Lee; Fan Lichu; Hu Shide

    2006-01-01

    This paper presents the first of a series of case studies on the seismic design of long span bridges (cablestayed bridges, suspension bridges and arch bridges) under a cooperative research project on seismic behavior and design of highway bridges between the State Key Laboratory for Disaster Reduction in Civil Engineering, Tongji University and the Multidisciplinary Center for Earthquake Engineering Research, University at Buffalo. The objective of this series of case studies is to examine the differences and similarities on the seismic design practice of long span bridges in China and the U.S., to identify research needs and to develop design guidelines beneficial to bridge engineers in both countries. Unlike short to medium span bridges, long span bridges are not included in most seismic design specifications, mainly because they are location dependent and structurally unique. In this paper, an available model of a steel tied half through arch bridge with a main span of 550m in China is discussed. Analysis is focused on comparisons of the seismic responses due to different ground motions. Seismic design criteria and seismic performance requirements for long span bridges in both countries were first introduced and compared, and then three near field earthquake records with large vertical components were selected as the excitations to examine the seismic behavior and seismic vulnerability of the bridge. Results show that (1) the selected near field ground motions cause larger responses to key components (critical sections) of the bridge (such as arch rib ends) with a maximum increase of more than twice those caused by the site specific ground motions; (2) piers, longitudinal girders and arch crowns are more vulnerable to vertical motions, especially their axial forces; and (3) large vertical components of near field ground motions may not significantly affect the bridge's internal forces provided that their peak acceleration spectra ordinates only appear at periods

  14. Burmese Arched Harp

    Science.gov (United States)

    Williamson, Robert M.

    Our knowledge of the history, construction, and tunings of the Burmese arched harp (saùng gauk) comes from a variety of sources. Conversations with master harpists, together with recordings made of their performances between 1960 and 1980, provide richly detailed examples of the effect of Western music on a non-Western musical tradition. Scholars' essays and conference proceedings complement these first-hand accounts, expanding our understanding of Burmese music and musical instruments.

  15. Tubular Steel Arch Stabilized by Textile Membranes

    Directory of Open Access Journals (Sweden)

    Ondrej Svoboda

    2016-10-01

    Full Text Available Tubular steel arch supporting textile membrane roofing is investigated experimentally and numerically. The stabilization effects of the textile membrane on in-plane and out-of-plane behavior of the arch is of primary interest. First a model of a large membrane structure tested in laboratory is described. Prestressed membranes of PVC coated polyester fabric Ferrari® Précontraint 702S were used as a currently standard and excellent material. The test arrangement, loading and resulting load/deflection values are presented. The supporting structure consisted of two steel arch tubes, outer at edge of the membrane and inner supporting interior of the membrane roofing. The stability and strength behavior of the inner tube under both symmetrical and asymmetrical loading was monitored and is shown in some details. Second the SOFiSTiK software was employed to analyze the structural behavior in 3D, using geometrically nonlinear analysis with imperfections (GNIA. The numerical analysis, FE mesh sensitivity, the membrane prestressing and common boundary conditions are validated by test results. Finally a parametrical study concerning stability of mid arch with various geometries in a membrane structure with several supporting arches is presented, with recommendations for a practical design.

  16. Three-dimensional measurement of foot arch in preschool children

    Directory of Open Access Journals (Sweden)

    Chang Hsun-Wen

    2012-09-01

    Full Text Available Abstract Background The prevalence of flexible flatfoot is high among preschool-aged children, but the effects of treatment are inconclusive due to the unclear definitions of normal flatfoot. To date, a universally accepted evaluation method of the foot arch in children has not been completely established. Our aims of this study were to establish a new method to evaluate the foot arch from a three dimensional perspective and to investigate the flexibility of the foot arch among children aged from two to six. Methods A total of 44 children aged from two to six years of age were put into five age groups in this study. The navicular height was measured with one leg standing, and both feet were scanned separately in both sitting and one leg standing positions to compute the foot arch volume. The arch volume index, which represents the ratio of the difference in volume between sitting and one leg standing positions to the volume when sitting was calculated to demonstrate the flexibility of the foot arch. The differences of measured parameters between each aged group were analyzed by one-way ANOVA. Results The arch volumes when sitting and standing were highly correlated with the navicular height. The navicular height ranged from 15.75 to 27 mm, the arch volume when sitting ranged from 6,223 to 11,630 mm3, and the arch volume when standing from 3,111 to 7,848 mm3 from two to six years of age. The arch volume index showed a declining trend as age increased. Conclusion This study is the first to describe the foot arch with volume perspective in preschool-aged children. The foot arch volume was highly correlated with the navicular height. Research results show both navicular height index and arch volume index gradually increase with age from two to six. At the same time the arch also becomes rigid with age from two to six. These results could be applied for clinical evaluation of the foot arch and post-treatment evaluation.

  17. A secondary analysis to determine variations of dental arch measurements with age and gender among Ugandans

    OpenAIRE

    Okori, Hilda; Apolot, Pricilla S.; Mwaka, Erisa; Tumusiime, Gerald; Buwembo, William; Munabi, Ian G.

    2015-01-01

    Background Dental arch dimensions are useful in dental practice and in forensic odontology. Local data is essential because ethnic differences exist in dental arch dimensions. In the Ugandan population no studies had been done on dental arch dimensions. The objective of the current study was to determine the variations in dental arch dimensions with age and gender in a sample of dental casts from the Ugandan population. Method This was a secondary analysis of dental casts previously prepared ...

  18. Tympanic ossicles and pharyngeal arches.

    Science.gov (United States)

    Whyte, J; Cisneros, A; Yus, C; Fraile, J; Obón, J; Vera, A

    2009-02-01

    We have performed a study on 11 human embryos regarding the development of the tympanic ossicles and their relationship with the first pharyngeal arch. After performing measurements to date the embryos and foetuses chronologically, we performed a meticulous dissection of the temporal bones. Subsequently, they were fixed in 10% formol, decalcified with 2% nitric acid, embedded in Paraplast, sectioned in 7-mm sequences and stained with Martin's trichrome technique. In the 21- and 24-mm cranium-raquis (CR) length human embryos, we have observed the head of the malleus and the body of the incus close to Meckel's cartilage, in addition to the handle of the malleus, the long limb of the incus and the stapes. Between them there was a mesenchymal band inside the primordium of the tympanic cavity. In the 27-mm CR embryo, the various components of the malleus and incus were fusing, and in the 30-mm CR embryo the union was complete. From our observations, we can conclude that the malleus and the incus are derived from the first and second pharyngeal arches.

  19. Effect of Obesity on Arch Index in Young Adults

    Directory of Open Access Journals (Sweden)

    Sneha Sameer Ganu

    2013-01-01

    Full Text Available Background: Excessive increases in weight bearing forces caused by obesity may negatively affect the lower limbs and feet but minimal research has examined the long-term loading effects of obesity on the musculoskeletal system, particularly in reference to the feet. Objectives: The purpose of the study was to investigate the effect of obesity on medial longitudinal arch of foot in young adults. Method: 60 subjects, 30 obese & 30 non obese were assessed for height & weight using standard technique. Radiographic images under static condition were used for calculating the arch index. Result: The arch index of obese subjects was significantly lower than the non obese subjects & there is a negative correlation between the BMI & the arch index. Conclusion: These results suggests that obesity lowers the medial longitudinal arch of foot.

  20. Key techniques and risk management for the application of the Pile-Beam-Arch (PBA) excavation method: a case study of the Zhongjie subway station.

    Science.gov (United States)

    Guan, Yong-ping; Zhao, Wen; Li, Shen-gang; Zhang, Guo-bin

    2014-01-01

    The design and construction of shallow-buried tunnels in densely populated urban areas involve many challenges. The ground movements induced by tunneling effects pose potential risks to infrastructure such as surface buildings, pipelines, and roads. In this paper, a case study of the Zhongjie subway station located in Shenyang, China, is examined to investigate the key construction techniques and the influence of the Pile-Beam-Arch (PBA) excavation method on the surrounding environment. This case study discusses the primary risk factors affecting the environmental safety and summarizes the corresponding risk mitigation measures and key techniques for subway station construction using the PBA excavation method in a densely populated urban area. PMID:25221783

  1. Key Techniques and Risk Management for the Application of the Pile-Beam-Arch (PBA Excavation Method: A Case Study of the Zhongjie Subway Station

    Directory of Open Access Journals (Sweden)

    Yong-ping Guan

    2014-01-01

    Full Text Available The design and construction of shallow-buried tunnels in densely populated urban areas involve many challenges. The ground movements induced by tunneling effects pose potential risks to infrastructure such as surface buildings, pipelines, and roads. In this paper, a case study of the Zhongjie subway station located in Shenyang, China, is examined to investigate the key construction techniques and the influence of the Pile-Beam-Arch (PBA excavation method on the surrounding environment. This case study discusses the primary risk factors affecting the environmental safety and summarizes the corresponding risk mitigation measures and key techniques for subway station construction using the PBA excavation method in a densely populated urban area.

  2. Precast Pearl-Chain concrete arch bridges

    DEFF Research Database (Denmark)

    Halding, Philip Skov; Hertz, Kristian Dahl; Schmidt, Jacob Wittrup

    2015-01-01

    A Pearl-Chain Bridge is a closed-spandrel arch bridge consisting of a number of straight pre-fabricated so called Super-Light Deck elements put together in an arch shape by post-tensioning cables. Several Pearl-Chain arches can be positioned adjacent to each other by a crane to achieve a bridge...... the technology was used. We also study other important components and details in the Pearl-Chain Bridge concept and review the effects of different types of loads. A theoretical case study of a circular 30 m span Pearl-Chain Bridge is presented showing the influence of a number of parameters: The number of post......-tensioning cables, the rise to span ratio, the height of the filling, and the height of the Super-Light Decks. We find that Pearl-Chain Bridges can be adjusted to resist specific moment loads by changing the normal force in the arch cross section by altering the above parameters. It is also found that the negative...

  3. Comparison of arch forms between Korean and North American white populations.

    Science.gov (United States)

    Kook, Yoon-Ah; Nojima, Kunihiko; Moon, Hong-Beom; McLaughlin, Richard P; Sinclair, Peter M

    2004-12-01

    The purpose of this study was to evaluate morphologic differences in the mandibular arches of Korean and North American white subjects. The subjects were grouped according to arch form (tapered, ovoid, and square) to compare the frequency distribution of the 3 arch forms between the ethnic groups in each Angle classification. The sample included 160 white (60 Class I, 50 Class II, and 50 Class III) and 368 Korean (114 Class I, 119 Class II, and 135 Class III) subjects. The most facial portion of 13 proximal contact areas was digitized from photocopied images of the mandibular dental arches. Clinical bracket points were calculated for each tooth according to mandibular tooth thickness data, and then 4 linear and 2 proportional measurements were taken. Arch width was statistically significantly smaller in the white group than in the Korean group, but arch depth did not differ. In the Korean group, the most frequent arch form was square, whereas in the white group the tapered arch form predominated. When the subjects were regrouped by arch form, the Korean arches had a tendency to be larger and deeper than the white arches within each of the 3 arch form types. PMID:15592215

  4. Computer-Guided Implant Surgery in Fresh Extraction Sockets and Immediate Loading of a Full Arch Restoration: A 2-Year Follow-Up Study of 14 Consecutively Treated Patients

    Directory of Open Access Journals (Sweden)

    M. Daas

    2015-01-01

    Full Text Available Statement of Problem. Low scientific evidence is identified in the literature for combining implant placement in fresh extraction sockets with immediate function. Moreover, the few studies available on immediate implants in postextraction sites supporting immediate full-arch rehabilitation clearly lack comprehensive protocols. Purpose. The purpose of this study is to report outcomes of a comprehensive protocol using CAD-CAM technology for surgical planning and fabrication of a surgical template and to demonstrate that immediate function can be easily performed with immediate implants in postextraction sites supporting full-arch rehabilitation. Material and Methods. 14 subjects were consecutively rehabilitated (13 maxillae and 1 mandible with 99 implants supporting full-arch fixed prostheses followed between 6 and 24 months (mean of 16 months. Outcome measures were prosthesis and implant success, biologic and prosthetic complications, pain, oedema evaluation, and radiographic marginal bone levels at surgery and then at 6, 12, 18, and 24 months. Data were analyzed with descriptive statistics. Results. The overall cumulative implant survival rate at mean follow-up time of 16 months was 97.97%. The average marginal bone loss was 0,9 mm. Conclusions. Within the limitations of this study, the results validate this treatment modality for full-arch rehabilitations with predictable outcomes and high survival rate after 2 years.

  5. Computer-Guided Implant Surgery in Fresh Extraction Sockets and Immediate Loading of a Full Arch Restoration: A 2-Year Follow-Up Study of 14 Consecutively Treated Patients.

    Science.gov (United States)

    Daas, M; Assaf, A; Dada, K; Makzoumé, J

    2015-01-01

    Statement of Problem. Low scientific evidence is identified in the literature for combining implant placement in fresh extraction sockets with immediate function. Moreover, the few studies available on immediate implants in postextraction sites supporting immediate full-arch rehabilitation clearly lack comprehensive protocols. Purpose. The purpose of this study is to report outcomes of a comprehensive protocol using CAD-CAM technology for surgical planning and fabrication of a surgical template and to demonstrate that immediate function can be easily performed with immediate implants in postextraction sites supporting full-arch rehabilitation. Material and Methods. 14 subjects were consecutively rehabilitated (13 maxillae and 1 mandible) with 99 implants supporting full-arch fixed prostheses followed between 6 and 24 months (mean of 16 months). Outcome measures were prosthesis and implant success, biologic and prosthetic complications, pain, oedema evaluation, and radiographic marginal bone levels at surgery and then at 6, 12, 18, and 24 months. Data were analyzed with descriptive statistics. Results. The overall cumulative implant survival rate at mean follow-up time of 16 months was 97.97%. The average marginal bone loss was 0,9 mm. Conclusions. Within the limitations of this study, the results validate this treatment modality for full-arch rehabilitations with predictable outcomes and high survival rate after 2 years. PMID:26064119

  6. Lucy's flat feet: the relationship between the ankle and rearfoot arching in early hominins.

    Directory of Open Access Journals (Sweden)

    Jeremy M DeSilva

    Full Text Available 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

  7. Semi- and Nonparametric ARCH Processes

    Directory of Open Access Journals (Sweden)

    Oliver B. Linton

    2011-01-01

    Full Text Available ARCH/GARCH modelling has been successfully applied in empirical finance for many years. This paper surveys the semiparametric and nonparametric methods in univariate and multivariate ARCH/GARCH models. First, we introduce some specific semiparametric models and investigate the semiparametric and nonparametrics estimation techniques applied to: the error density, the functional form of the volatility function, the relationship between mean and variance, long memory processes, locally stationary processes, continuous time processes and multivariate models. The second part of the paper is about the general properties of such processes, including stationary conditions, ergodic conditions and mixing conditions. The last part is on the estimation methods in ARCH/GARCH processes.

  8. Clinical effects of lateral wedge arch support insoles in knee osteoarthritis: A prospective double-blind randomized study.

    Science.gov (United States)

    Hsieh, Ru-Lan; Lee, Wen-Chung

    2016-07-01

    We compared the short-term efficacy of rigid versus soft lateral wedge arch support (LWAS) insoles for patients with knee osteoarthritis (OA), as assessed using the International Classification of Functioning, Disability and Health (ICF) system, through a prospective, double-blind, randomized controlled trial.Participants who fulfilled the combined radiographic and clinical criteria for knee OA, as defined by the American College of Rheumatology, were randomly prescribed 1 pair of rigid or soft LWAS insoles. Body functions and structures were evaluated according to Kellgren-Lawrence scores, the Foot Posture Index, Hospital Anxiety and Depression Scale scores, the pain-pressure threshold, postural stability, dynamic balance, and fall risk; activities and participation were assessed according to 10-m fast speed walking, stair climbing and chair rising times, and Chronic Pain Grade questionnaire responses; and knee OA-related health status was evaluated using the Knee Injury and Osteoarthritis Outcome Score (KOOS). Hospital Anxiety and Depression Scale scores, the pain-pressure threshold, physical activity, balance, Chronic Pain Grade questionnaire responses, and the KOOS were recorded before treatment and at 1-, 2-, and 3-month follow-ups.We enrolled 90 participants, 70 women and 20 men, with mean ages of 60.6 ± 10.8 and 63.1 ± 10.8 years in the rigid and soft LWAS insole groups, respectively. Repeated-measures analysis of covariance revealed significant time × group effect improvements in pain (P = 0.008 for the KOOS), stair ascent time (P = 0.003), daily living function (P = 0.003 for the KOOS), sports and recreation function (P = 0.012 for the KOOS), and quality of life (P = 0.021 for the KOOS) in the soft LWAS insole group.Patients with knee OA who used soft LWAS insoles for a short term showed more significant improvement than did those who used rigid LWAS insoles in pain, physical activity, daily living function, sports and recreation function

  9. 拱结构形态在建筑局部和整体形象的艺术表现解析%Study on the artistic expression of arch structure in building

    Institute of Scientific and Technical Information of China (English)

    余秋雨; 徐伟琦

    2015-01-01

    通过解读建筑案例,探究拱结构形态对建筑局部和整体形象表现的作用,在拱结构的传统应用与衍变中,试图找到建筑艺术与结构形态之间的关系以及拱结构形态表现建筑艺术的原因,并通过详细分析、论证一些国内外的著名建筑案例,整理归纳拱结构形态的艺术化处理规律和总结拱结构形态的表现手法.此外,该文研究的拱结构主要是以砖石为材料的传统拱结构在建筑方面的应用,因此我们探究的主要方向是砖石拱结构在建筑美学方面的表现.%This article illustrates the artistic expression of arch in partial and integral building by studying cases. During the construction of conventional application and evolution, both the correlations between structure and art of architecture, and the reasons of arch presenting are trying to be identified. The arch art and present methods are summarized by analyzing and demonstrating foreign cases. Moreover, since this article researches the brick and stone arch in building, it mainly explores the presentation of brick and stone arch in architectural aesthetics.

  10. The assessment of crowding without the need to record arch perimeter. Part I: Arches with acceptable alignment.

    Science.gov (United States)

    Battagel, J M

    1996-05-01

    A simplified, mathematically determined technique for calculating arch perimeter (the overlap method) is described and its validity in determining an accurate assessment of crowding is tested. Indices, expressed in millimetres of crowding or spacing, were computed for both the whole arch and the labial segment alone. Study casts of 36 individuals with clinically acceptable lower arches were used to validate the method. The degree of crowding or spacing calculated was compared with a "clinical' assessment of each arch, in which the irregularity was measured directly using a steel ruler. Various calculation schemes were tested. Depending on exactly how the overlap was determined, the results varied slightly. Although the arches showed acceptable alignment, it was preferable to include a strategy for normalizing the positions of any rotated teeth before the overlaps were calculated. Repositioning any bucco-lingually displaced teeth into the line of the arch, however, was not useful. For the complete arch good agreement with the clinical assessment was reached on 31 occasions and for the labial segment, all but one appraisals were within 0.5 mm of each other. In the remaining instances (five complete arches and one labial segment), the degree of crowding or spacing was between 0.5 and 1 mm of the clinical assessment. Considering that clinical measurement of minor degrees of crowding and spacing cannot be precise, these results were considered acceptable. The method was easy to use, relying only on the recording of mesio-distal tooth widths and was acceptably reproducible. The technique would therefore appear to provide a valid yet simple research tool with which to record the degree of crowding. Its ability to cope with irregular and crowded arches will be the subject of a subsequent review.

  11. Comparison of arch forms between Turkish and North American

    OpenAIRE

    Ahmet A. Celebi; Hakan Keklik; Enes Tan; 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 ...

  12. Computer-Guided Implant Surgery in Fresh Extraction Sockets and Immediate Loading of a Full Arch Restoration: A 2-Year Follow-Up Study of 14 Consecutively Treated Patients

    OpenAIRE

    2015-01-01

    Statement of Problem. Low scientific evidence is identified in the literature for combining implant placement in fresh extraction sockets with immediate function. Moreover, the few studies available on immediate implants in postextraction sites supporting immediate full-arch rehabilitation clearly lack comprehensive protocols. Purpose. The purpose of this study is to report outcomes of a comprehensive protocol using CAD-CAM technology for surgical planning and fabrication of a surgical templa...

  13. 抗滑桩的土拱效应研究%Study on the soil arching effect of anti slide pile

    Institute of Scientific and Technical Information of China (English)

    何国峰; 柴琳琳; 刘颖

    2014-01-01

    Be aimed at the effect of the arrangement of anti slide pile of the interaction between pile and soil caused by landslide treatment engi-neering soil arching effect,and combined with the results of previous studies,to determine the potential sliding surface of landslide,and to calcu-late the landslide thrust,then use the finite element software PLAXIS to analyze the potential landslide,and ultimately determined the optimal pile spacing about pile design of landslide engineering,and provides a basis for the design of anti slide pile in practical engineering.%针对滑坡治理工程中抗滑桩与土体的相互作用引起的土拱效应对抗滑桩布桩的影响,结合已有的研究成果,对滑坡确定潜在滑动面,计算出滑坡推力,并基于PLAXIS有限元软件对潜在滑坡进行了分析计算,最终确定了此次滑坡工程中抗滑桩设计的最佳桩间距,为实际工程中抗滑桩的设计提供了依据。

  14. Developmental feature of the lumbosacral vertebral arch in childhood

    International Nuclear Information System (INIS)

    We investigated a developmental feature of the lumbosacral vertebral arch in childhood that has rarely been reported previously. Sixty-seven patients underwent functional posterior rhizotomy from September 2000 to June 2006 at National Center for Child Health and Development. Sixty of these patients, who had no deformity in their lumbosacral spine, were included in this study and their Computed Tomography (CT) images were analyzed retrospectively. There were 36 boys and 24 girls, aged from 2-12 years. The rate and mean number of non-union vertebral arches between L1 and S3 were 78.3% (95% CI, 65.8-87.9%) and 1.7 (standard deviation (SD), 1.3). The non-union arch was most frequently found at the S1 level, and was more significantly observed in the younger age group (2-5 years of age). The S4 and S5 arches, which often remained open as the sacral hiatus, were constantly open in childhood. This study demonstrates that the vertebral arches of the lumbosacral spine in normal development are often not fused during childhood. It is important to differentiate normal non-union arches from pathological spina bifida. (author)

  15. Clarifying the anatomy of the fifth arch artery

    Directory of Open Access Journals (Sweden)

    Saurabh Kumar Gupta

    2016-01-01

    Full Text Available 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.

  16. Comparison of arch forms between Turkish and North American

    Directory of Open Access Journals (Sweden)

    Ahmet A. Celebi

    2016-04-01

    Full Text Available 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.

  17. The Foot’s Arch and the Energetics of Human Locomotion

    Science.gov (United States)

    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

  18. Study of Key Construction Control Technique of Steel Pipe Concrete Arched Bridge%钢管混凝土拱桥施工控制关键技术研究

    Institute of Scientific and Technical Information of China (English)

    王亚超; 张晋

    2009-01-01

    该文结合湖州市奚家庄大桥主拱施工监控方案,运用有限元分析程序和现代测量手段相结合,对钢管混凝土拱桥施工控制中的关键技术进行了深入的研究,可供同类工程施工参考.%Combined with the main arch construction monitoring scheme of Huzhou City Xijiazhuang Bridge, the article uses the finite element analysis program and the modern measuring means to deeply study the key technique in the construction control of steel pipe concrete arched bridge, which can be referred for the similar projects.

  19. Effect of removable partial dentures on oral health-related quality of life in subjects with shortened dental arches: a 2-center cross-sectional study.

    NARCIS (Netherlands)

    Armellini, D.B.; Heydecke, G.; Witter, D.J.; Creugers, N.H.J.

    2008-01-01

    PURPOSE: To assess the value of removable partial dentures (RPDs) in subjects with shortened dental arches (SDAs) with regard to quality of life. MATERIALS AND METHODS: Subjects from 2 university dental centers (82 men, 78 women; mean age: 54 +/- 18 years) were categorized into the following groups:

  20. First hard X-ray detection of the non-thermal emission around the Arches cluster: morphology and spectral studies with NuSTAR

    DEFF Research Database (Denmark)

    Krivonos, Roman A.; Tomsick, John A.; Bauer, Franz E.;

    2014-01-01

    The Arches cluster is a young, densely packed massive star cluster in our Galaxy that shows a high level of star formation activity. The nature of the extended non-thermal X-ray emission around the cluster remains unclear. The observed bright Fe Ku line emission at 6.4 keV from material that is n...

  1. Theory of Arched Structures Strength, Stability, Vibration

    CERN Document Server

    Karnovsky, Igor A

    2012-01-01

    Theory of Arched Structures: Strength, Stability, Vibration presents detailed procedures for analytical analysis of the strength, stability, and vibration of arched structures of different types, using exact analytical methods of classical structural analysis. The material discussed is divided into four parts. Part I covers stress and strain with a particular emphasis on analysis; Part II discusses stability and gives an in-depth analysis of elastic stability of arches and the role that matrix methods play in the stability of the arches; Part III presents a comprehensive tutorial on dynamics and free vibration of arches, and forced vibration of arches; and Part IV offers a section on special topics which contains a unique discussion of plastic analysis of arches and the optimal design of arches.

  2. Gender identification and morphologic classification of tooth, arch and palatal forms in Saudi population

    OpenAIRE

    Mohammad, Aljanakh; Koralakunte, Pavankumar Ravi

    2015-01-01

    Aims: To determine various tooth form, arch form, and palatal form with gender identification between males and females of the Saudi population. Materials and Methods: Irreversible hydrocolloid impressions were made of the maxillary teeth of 100 dentate male and female subjects to obtain study casts. A standardized procedure was adopted to photograph the maxillary dental arches and the maxillary central incisors on the study casts taken from each subject. The outline form of tooth, arch, and ...

  3. Frontal plane multi-segment foot kinematics in high- and low-arched females during dynamic loading tasks.

    Science.gov (United States)

    Powell, Douglas W; Long, Benjamin; Milner, Clare E; Zhang, Songning

    2011-02-01

    The functions of the medial longitudinal arch have been the focus of much research in recent years. Several studies have shown kinematic differences between high- and low-arched runners. No literature currently compares the inter-segmental foot motion of high- and low-arched recreational athletes. The purpose of this study was to examine inter-segmental foot motion in the frontal plane during dynamic loading activities in high- and low-arched female athletes. Inter-segmental foot motions were examined in 10 high- and 10 low-arched female recreational athletes. Subjects performed five barefooted trials in each of the following randomized movements: walking, running, downward stepping and landing. Three-dimensional kinematic data were recorded. High-arched athletes had smaller peak ankle eversion angles in walking, running and downward stepping than low-arched athletes. At the rear-midfoot joint high-arched athletes reached peak eversion later in walking and downward stepping than the low-arched athletes. The high-arched athletes had smaller peak mid-forefoot eversion angles in walking, running and downward stepping than the low-arched athletes. The current findings show that differences in foot kinematics between the high- and low-arched athletes were in position and not range of motion within the foot.

  4. Experimental behavior of FRP strengthened masonry arches

    OpenAIRE

    Oliveira, Daniel V.; Basílio, Ismael; Lourenço, Paulo B.

    2010-01-01

    This paper deals with the experimental behavior of solid clay brick masonry arches strengthened with glass fiber reinforced polymer composites. Twelve half-scaled segmental masonry arches subjected to a load applied at the quarter span were tested under displacement control up to failure. The arches were built using handmade low strength bricks and a commercial lime-based mortar, trying to mimic ancient structures. Besides reference unreinforced arches, five different strengthening arrangemen...

  5. Displacements Prediction in Double-Arch Dam Rock Abutment Using SPSS Software Based on Extensometer Readings Case study: Karun 4 Concrete Dam, Iran

    Directory of Open Access Journals (Sweden)

    Hadi kamali Bandpey

    2012-11-01

    Full Text Available In this study we present a method for Displacements Prediction in Double-Arch Dam Rock Abutment Using SPSS Software Based on Extensometer Readings. Displacement in dams is the most tangible and important parameter which could be crucial in their safety. Different elevation displacements are yielded by various loadings and the thrust force imposed on foundation and abutment. Most concrete dams are constructed on stone foundations. Displacements in foundation and abutment are measured by extensometers. Karun 4 Concrete dam is designed with 11 galleries, from elevation 1016 to 802 m, in the order from top elevation (dam crest elevation 1032 to the bottom elevation (dam foundation elevation 806 within the dam body. As a whole, 19 extensometers in the left bank, 17 in the right, and one more in the middle are implemented in the dam. Karun 4 dam has already been impounded with water up to the elevation 1003. Displacements in Karun 4 are recorded by extensometers whence water was leveled in 7 elevations 943.68, 953.36, 973.55, 983.28, 993.17, 1003.13. In this study, using SPSS we have tried to predict the displacements for a situation in which water will be elevated to the elevations 1013, 1023, 1032 in the future for elevations which are equipped with anchor. The most predicted displacement pertaining to the left bank when water was leveled to the elevation 1013, was 3.65 mms by R2 = 0.9997 for the implemented anchor. Proceeding further, as water is leveled to the elevations 1023 and 1033, the most predicted displacement respectively would be 4.31 and 5.66 by R2 = 0.9941; and is related to the anchor implemented in the elevation 936.05. The most predicted displacement for the right bank is 5.9397, 7.2347 and 8.6877 mms by R2 = 0.9995 for the elevation 888.128 m.

  6. Study on Simplified Model Construction Method of Dumbbell Shape Steel Pipe Concrete Arch Rib%哑铃形钢管混凝土拱肋简化建模方法研究

    Institute of Scientific and Technical Information of China (English)

    唐必刚; 张小华; 彭益华

    2012-01-01

    As the main stress component of steel pipe concrete arch bridge, whether the model construction method of dumbbell shape steel pipe concrete arch rib is reasonable is very significant to the structural safety of the whole bridge.By using MIDAS software, the arti- cle made various simplified simulation of the dumbbell shape steel pipe concrete arch db, and compared the calculations based on these simplified model with those based on the plates and solid element models constructed by using ANSYS software, so as to study and discuss simplified model construction methods which are more reasonable and more applicable.%哑铃形钢管混凝土拱肋作为钢管混凝土拱桥的主要受力构件,其建模方法是否合理对全桥结构的安全性具有重要的意义。文章采用MIDAS软件,对哑铃形钢管混凝土拱肋进行了多种简化模拟,并将这些简化模型计算结果与运用AN—SYS软件建立的板、实体单元模型的计算结果进行了比较,以研究探讨较为合理适用的简化建模方法。

  7. Effect of prosthetic restoration on oral health-related quality of life in patients with shortened dental arches: a multicentre study.

    Science.gov (United States)

    Fueki, K; Igarashi, Y; Maeda, Y; Baba, K; Koyano, K; Sasaki, K; Akagawa, Y; Kuboki, T; Kasugai, S; Garrett, N R

    2015-09-01

    The aim of this multicentre prospective study was to investigate the effect of prosthetic restoration for missing posterior teeth in patients with shortened dental arches (SDAs). SDA patients with 2-12 missing occlusal units (a pair of occluding premolars corresponds to one unit, and a pair of occluding molars corresponds to two units) were consecutively recruited from seven university-based dental hospitals in Japan. Patients chose no replacement of missing teeth or prosthetic treatment with removable partial dentures (RPDs) or implant-supported fixed partial dentures (IFPDs). Oral health-related quality of life (OHRQoL) was measured using the oral health impact profile (Japanese version - OHIP-J) at baseline and follow-up/post-treatment evaluation. Of the 169 subjects who completed baseline evaluation, 125 subjects (mean age; 63.0 years) received follow-up/post-treatment evaluation. No-treatment was chosen by 42% (53/125) of the subjects, and 58% (72/125) chose treatment with a RPD (n = 53) or an IFPD (n = 19). In the no-treatment (NT) group, the mean OHIP summary score at baseline was similar to that at follow-up evaluation (P = 0.69). In the treatment (TRT) group, the mean OHIP summary score decreased significantly after the RPD treatment (P = 0.002), and it tended to decrease, though not statistically significant (P = 0.18), after the IFPD treatment. The restoration of one occlusal unit was associated with a 1.2-point decrease in OHIP summary score (P = 0.034). These results suggest that the replacement of missing posterior teeth with RPDs or IFPDs improved OHRQoL. Prosthetic restoration for SDAs may benefit OHRQoL in patients needing replacement of missing posterior teeth. PMID:25818656

  8. Dermatoglyphic assessment in subjects with different dental arch forms: an appraisal.

    Science.gov (United States)

    Sachdeva, Shabina; Tripathi, Arvind; Kapoor, Pranav

    2014-09-01

    Successful rehabilitation of edentulous individuals involves selection and arrangement of artificial teeth in accordance with the patient's original arch form. Various criteria exist for harmonious tooth arrangement but none is accepted universally. Finger and palm prints are unique to an individual and once formed in the sixth week of intra-uterine life, remain constant thereafter. Since dental arches are also formed during the same prenatal period, it is believed that the similar genetic factors may be involved in formation of dental arches and dermal patterns. This study was conducted to identify the association if any between type of dental arch forms and type of dermatoglyphic patterns. If specific dermal characteristics exist in individuals with specific dental arch forms, dermatoglyphic assessment of long standing edentulous subjects may help identify the patients preexisting dental arch form and thus aid in proper tooth arrangement. Ninety dentulous subjects were categorized into three groups on the basis of dental arch form (square, tapering or ovoid) and their finger and palm prints were recorded. The type of fingertip patterns, distribution of palmar patterns, Total Finger Ridge Count and angle atd were assessed. Subjects with square arches demonstrated a significantly high frequency of loops and a large atd angle with palmar patterns being most frequent in I3 region. Subjects with tapering arches showed a high frequency of whorls, a small atd angle and greatest distribution of palmar patterns in I4 region. In ovoid arched subjects, loops were the most common and palmar patterns were mostly observed in I4. Since distinctive dermal patterns were observed in subjects with different dental arch forms, it is believed that dermatoglyphics may be used as a reliable tool for identifying original arch form in edentulous patients. PMID:25183912

  9. Three-dimensional stiffness of the carpal arch.

    Science.gov (United States)

    Gabra, Joseph N; Li, Zong-Ming

    2016-01-01

    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±4.6N/mm that was significantly larger than the other principal components of 3.1±0.9 and 2.6±0.5N/mm (pcarpal 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.

  10. 探究桩网复合地基中的土拱效应%Study of the Soil Arching Effect in Pile Net Composite Foundation

    Institute of Scientific and Technical Information of China (English)

    梁文文; 田浩

    2014-01-01

    土拱效应能够调节探究桩网复合地基中桩顶的预应力和沉降。本文针对实际情况下的土拱效应的发展变化规律进行单桩数值模拟和数学解析,根据荷载下复合地基的荷载传递机理及变形特征,综合考虑路堤填土的土拱效应和桩、土的荷载传递性状。%Soil arching effect can regulate and inquiry the prestress and set lement of pile block in net composite fou-ndation. This article in view of the actual situation of the development changing rule of the soil arch effect makes nu-merical simulation and mathematical analysis of the single pi-le, according to the transfermechanism and deformation char-acteristics of the composite foundation under the load of lo-ad, considers the load transfer of embankment soil arching ef-fectand, pile and soil properties.

  11. First Hard X-Ray Detection of the Non-Thermal Emission Around the Arches Cluster: Morphology and Spectral Studies With NuSTAR

    Science.gov (United States)

    Krivonos, Roman A.; Tomsick, John A.; Bauer, Franz E.; Baganoff, Frederick K.; Barriere, Nicolas M.; Bodaghee, Arash; Boggs, Steven E.; Christensen, Finn E.; Craig, William W.; Grefenstette, Brian W.; Hailey, Charles J.; Harrison, Fiona A.; Hong, JaeSub; Madsen, Kristin K.; Mori, Kaya; Nynka, Melania; Stern, Daniel; Zhang, William W.

    2014-01-01

    The Arches cluster is a young, densely packed massive star cluster in our Galaxy that shows a high level of star formation activity. The nature of the extended non-thermal X-ray emission around the cluster remains unclear. The observed bright Fe K(alpha) line emission at 6.4 keV from material that is neutral or in a low ionization state can be produced either by X-ray photoionization or by cosmic-ray particle bombardment or both. In this paper, we report on the first detection of the extended emission around the Arches cluster above 10 keV with the NuSTAR mission, and present results on its morphology and spectrum. The spatial distribution of the hard X-ray emission is found to be consistent with the broad region around the cluster where the 6.4 keV line is observed. The interpretation of the hard X-ray emission within the context of the X-ray reflection model puts a strong constraint on the luminosity of the possible illuminating hard X-ray source. The properties of the observed emission are also in broad agreement with the low-energy cosmic-ray proton excitation scenario. Key words: cosmic rays - Galaxy: center - ISM: general - X-rays: individual (Arches cluster)

  12. Study on the relationship between dental arch form,alveolar arch form and facial morphology of young males%正常(牙)清年男性牙弓、牙槽弓形态与软组织面型关系的研究

    Institute of Scientific and Technical Information of China (English)

    庾英姿; 米丛波; 祖青; 梁其彬; 林成; 谭红征

    2011-01-01

    Objective To investigate the relation between dental arch forms.alveolar arch form and facial morphology. Methods The subjects consisted of 69 males with nomal occlusion(mean aged 23.6 years).The cast were obtained.The width and length of the dental arch and alveolar arch were measured.Correlation analysis was done between the measurement of dental arch form.alveolar arch form and facial Morphology index and facial proportion. Results There were significantly poisitive relationships between the width of the dental arch and alveolar arch and bizygomatic facial width (BFW),the width of the alveolar arch and intergonial width (IGW).Aiveolar arch width,maxillary anterior and middle dental arch had relation to corpus length (CL),and the alveolar arch length,width and mandibular antero-middle dental arch had relation to mandibular length (ML).There were significantly poisitive relationships between the length of the mandibular anterior dental arch and AFH/IGW.There were significantly negative relationships between maxillary intercanine alveolar arch width and AFH/BFW. Conclusion Dental arch form.alveolar arch form are associated with facial morphology.Attention should be paid to the matching and correlation between dental arch forms.alveolar arch form and facial morphology during orthodontic treatment.%目的:了解牙弓、牙槽弓形态与软组织面型的关系,为正畸临床提供依据.方法:选择正常(牙)青年男性69例,取模并测量其牙弓、牙槽弓宽度、长度并与颅面软组织形态指标测量结果及面型比例进行统计学相关分析.结果:牙弓、牙槽弓宽度与面中宽(BFW),牙槽弓宽度与面下宽(IGW)呈正相关;牙槽弓宽度及上颌前、中段牙弓宽度与下颌骨体长(CL),牙槽弓长度、宽度及下颌牙弓前中段长度与下颌骨长(ML)呈正相关.上颌前段牙弓长度与前面高与面下宽度之比(AFH/ IGW)呈正相关;上颌尖牙间牙槽弓宽度与前面高与面中宽度之比(AFH/ BFW)

  13. A Functional Version of the ARCH Model

    CERN Document Server

    Hormann, Siegfried; Reeder, Ron

    2011-01-01

    Improvements in data acquisition and processing techniques have lead to an almost continuous flow of information for financial data. High resolution tick data are available and can be quite conveniently described by a continuous time process. It is therefore natural to ask for possible extensions of financial time series models to a functional setup. In this paper we propose a functional version of the popular ARCH model. We will establish conditions for the existence of a strictly stationary solution, derive weak dependence and moment conditions, show consistency of the estimators and perform a small empirical study demonstrating how our model matches with real data.

  14. The Arches Cluster Mass Function

    CERN Document Server

    Kim, S S; Kudritzki, R P; Najarro, F; Kim, Sungsoo S.; Figer, Donald F.; Kudritzki, Rolf P.

    2006-01-01

    We have analyzed H and K_s-band images of the Arches cluster obtained using the NIRC2 instrument on Keck with the laser guide star adaptive optics (LGS AO) system. With the help of the LGS AO system, we were able to obtain the deepest ever photometry for this cluster and its neighborhood, and derive the background-subtracted present-day mass function (PDMF) down to 1.3 Msun for the 5 arcsec-9 arcsec annulus of the cluster. We find that the previously reported turnover at 6 Msun is simply due to a local bump in the mass function (MF), and that the MF continues to increase down to our 50 % completeness limit (1.3 Msun) with a power-law exponent of Gamma = -0.91 for the mass range of 1.3 < M/Msun < 50. Our numerical calculations for the evolution of the Arches cluster show that the Gamma values for our annulus increase by 0.1-0.2 during the lifetime of the cluster, and thus suggest that the Arches cluster initially had Gamma of -1.0 ~ -1.1, which is only slightly shallower than the Salpeter value.

  15. Cephalic arch stenosis in autogenous brachiocephalic hemodialysis fistulas: results of cutting balloon angioplasty

    DEFF Research Database (Denmark)

    Heerwagen, Søren Thorup; Lönn, Lars; Schroeder, Torben V;

    2010-01-01

    Cephalic arch stenosis is a known cause of hemodialysis access failure in patients with brachiocephalic fistulas (BCFs). Outcomes of endovascular treatment are affected by resistance of the stenosis to balloon dilation, a high vein rupture rate and the development of early restenosis. The purpose...... of this retrospective study was to report outcomes after cutting balloon angioplasty (CBA) of cephalic arch stenosis....

  16. Blood flow characteristics in the aortic arch

    Science.gov (United States)

    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.

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

    Directory of Open Access Journals (Sweden)

    Rakhn G. Al-Barakati

    2016-01-01

    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.

  18. Experimental study of soil arching of geogrid-reinforced and pile-supported widening embankment%桩-网加固拓宽路堤土拱效应试验研究

    Institute of Scientific and Technical Information of China (English)

    吕伟华; 缪林昌; 王非; 蔡海粟; 张成相

    2013-01-01

    Soil arching is very important for analyzing the stress state of existing and widening embankment and differential settlement between piles (caps) and subsoil. In this paper, the behavior of soil arching is analyzed for a widening embankment which is supported by rigid piles with caps and reinforced by geogrid. Based on the test site of the widening expressway project, earth pressures on caps and subsoil at the bottom and at different depths to fill surface are investigated; and tensile strains of the geogrid are monitored too. Then stress concentration ratios and soil arching ratios are analyzed and compared with several current design methods, including the Guido method, the BS8006 method, the Kempfert method and the Low method. Results show that, a two-dimensional plane soil arching fill load distribution on caps and subsoil within a critical arch height which is deduced to be 2.0 m owing a ratio of 1.4 the pile clear spacing, and is consistent with BS8006. The Guido and BS8006 methods were too conservative on assessing tensile strain of geogrid; Except for the Guido method, all rest presented design methods underestimated the resistance from the compressible subsoil. So, further study and a better understanding of soil arching should be developed.%  采用桩-网加固拓宽路堤时,土拱效应对于分析新老路堤应力分布和差异沉降有至关重要的作用。依托某高速公路路堤拓宽项目对土拱效应进行研究,对试验段新路堤填筑过程及运营时基底桩及桩间土不同位置处土压力、加筋层拉应变进行监测,得到二维平面土拱效应的变化规律,并利用已有土拱效应计算方法对现场实测结果进行对比验证。结果表明,平面土拱作用范围在一定高度范围内,试验段约为2.0 m,即拱高、拱跨之比约为1.4,与英国规范 BS8006[1]相近;按 Guido 法[2]与 BS8006法[3]进行土工格栅的设计均过于保守,除 Guido 法以外,几种方

  19. Clinical Advantages and Limitations of Monolithic Zirconia Restorations Full Arch Implant Supported Reconstruction: Case Series

    Directory of Open Access Journals (Sweden)

    Joao Carames

    2015-01-01

    Full Text Available 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.

  20. Optical silencing of C. elegans cells with arch proton pump.

    Directory of Open Access Journals (Sweden)

    Ayako Okazaki

    Full Text Available BACKGROUND: Optogenetic techniques using light-driven ion channels or ion pumps for controlling excitable cells have greatly facilitated the investigation of nervous systems in vivo. A model organism, C. elegans, with its small transparent body and well-characterized neural circuits, is especially suitable for optogenetic analyses. METHODOLOGY/PRINCIPAL FINDINGS: We describe the application of archaerhodopsin-3 (Arch, a recently reported optical neuronal silencer, to C. elegans. Arch::GFP expressed either in all neurons or body wall muscles of the entire body by means of transgenes were localized, at least partially, to the cell membrane without adverse effects, and caused locomotory paralysis of worms when illuminated by green light (550 nm. Pan-neuronal expression of Arch endowed worms with quick and sustained responsiveness to such light. Worms reliably responded to repeated periods of illumination and non-illumination, and remained paralyzed under continuous illumination for 30 seconds. Worms expressing Arch in different subsets of motor neurons exhibited distinct defects in the locomotory behavior under green light: selective silencing of A-type motor neurons affected backward movement while silencing of B-type motor neurons affected forward movement more severely. Our experiments using a heat-shock-mediated induction system also indicate that Arch becomes fully functional only 12 hours after induction and remains functional for more than 24 hour. CONCLUSIONS/SGNIFICANCE: Arch can be used for silencing neurons and muscles, and may be a useful alternative to currently widely used halorhodopsin (NpHR in optogenetic studies of C. elegans.

  1. First hard x-ray detection of the non-thermal emission around the arches cluster: Morphology and spectral studies with NuSTAR

    Energy Technology Data Exchange (ETDEWEB)

    Krivonos, Roman A.; Tomsick, John A.; Barriere, Nicolas M.; Bodaghee, Arash; Boggs, Steven E.; Craig, William W. [Space Science Lab, University of California, Berkeley, CA 94720 (United States); Bauer, Franz E. [Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Catlica de Chile, Casilla 306, Santiago 22 (Chile); Baganoff, Frederick K. [MIT Kavli Institute for Astrophysics and Space Research, Cambridge, MA 02139 (United States); Christensen, Finn E. [DTU Space-National Space Institute, Technical University of Denmark, Elektrovej 327, DK-2800 Lyngby (Denmark); Grefenstette, Brian W.; Harrison, Fiona A.; Madsen, Kristin K. [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, Pasadena, CA 91125 (United States); Hailey, Charles J.; Mori, Kaya; Nynka, Melania [Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Hong, JaeSub [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Stern, Daniel [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Zhang, William W., E-mail: krivonos@ssl.berkeley.edu [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2014-02-01

    The Arches cluster is a young, densely packed massive star cluster in our Galaxy that shows a high level of star formation activity. The nature of the extended non-thermal X-ray emission around the cluster remains unclear. The observed bright Fe Kα line emission at 6.4 keV from material that is neutral or in a low ionization state can be produced either by X-ray photoionization or by cosmic-ray particle bombardment or both. In this paper, we report on the first detection of the extended emission around the Arches cluster above 10 keV with the NuSTAR mission, and present results on its morphology and spectrum. The spatial distribution of the hard X-ray emission is found to be consistent with the broad region around the cluster where the 6.4 keV line is observed. The interpretation of the hard X-ray emission within the context of the X-ray reflection model puts a strong constraint on the luminosity of the possible illuminating hard X-ray source. The properties of the observed emission are also in broad agreement with the low-energy cosmic-ray proton excitation scenarioþ.

  2. First hard x-ray detection of the non-thermal emission around the arches cluster: Morphology and spectral studies with NuSTAR

    International Nuclear Information System (INIS)

    The Arches cluster is a young, densely packed massive star cluster in our Galaxy that shows a high level of star formation activity. The nature of the extended non-thermal X-ray emission around the cluster remains unclear. The observed bright Fe Kα line emission at 6.4 keV from material that is neutral or in a low ionization state can be produced either by X-ray photoionization or by cosmic-ray particle bombardment or both. In this paper, we report on the first detection of the extended emission around the Arches cluster above 10 keV with the NuSTAR mission, and present results on its morphology and spectrum. The spatial distribution of the hard X-ray emission is found to be consistent with the broad region around the cluster where the 6.4 keV line is observed. The interpretation of the hard X-ray emission within the context of the X-ray reflection model puts a strong constraint on the luminosity of the possible illuminating hard X-ray source. The properties of the observed emission are also in broad agreement with the low-energy cosmic-ray proton excitation scenarioþ

  3. First hard X-ray detection of the non-thermal emission around the Arches cluster: morphology and spectral studies with NuSTAR

    CERN Document Server

    Krivonos, Roman A; Bauer, Franz E; Baganoff, Frederick K; Barriere, Nicolas M; Bodaghee, Arash; Boggs, Steven E; Christensen, Finn E; Craig, William W; Grefenstette, Brian W; Hailey, Charles J; Harrison, Fiona A; Hong, JaeSub; Madsen, Kristin K; Mori, Kaya; Nynka, Melania; Stern, Daniel; Zhang, William W

    2013-01-01

    The Arches cluster is a young, densely packed massive star cluster in our Galaxy that shows a high level of star formation activity. The nature of the extended non-thermal X-ray emission around the cluster remains unclear. The observed bright Fe K_alpha line emission at 6.4 keV from material that is neutral or in a low ionization state can be produced either by X-ray photoionization or by cosmic-ray particle bombardment or both. In this paper we report on the first detection of the extended emission around the Arches cluster above 10 keV with the NuSTAR mission, and present results on its morphology and spectrum. The spatial distribution of the hard X-ray emission is found to be consistent with the broad region around the cluster where the 6.4 keV line is observed. The interpretation of the hard X-ray emission within the context of the X-ray reflection model puts a strong constraint on the luminosity of the possible illuminating hard X-ray source. The properties of the observed emission are also in broad agre...

  4. Clinical Study of Micro-implant Treatment for Dental Arch Protrusion%微型种植体支抗治疗上牙弓前突的临床研究

    Institute of Scientific and Technical Information of China (English)

    张俊峰

    2011-01-01

    目的:研究微型种植体作为强支抗解决上牙弓前突的有效性.方法:选择严重上牙弓前突的患者12例,减数拔除上颌双侧第一前磨牙,种植体植入上颌第一磨牙和第二前磨之间膜龈结合处,以滑动法整体内收6颗上前牙.通过X线头颅定位侧位片的测量方法,观察切牙和磨牙的位置变化.结果:牙弓突度均得到明显改善,治疗后上颌切牙切端水平内收7.49 mm,上切牙牙轴平均减少12.46°,上颌第一磨牙平均前移0.32 mm.上颌切牙治疗前后差异有统计学意义(P<0.05),上颌磨牙近中位移治疗前后差异无统计学意义.全部病例均获得理想的侧貌改变,前牙覆(牙合)覆盖正常,建立上下磨牙的中性关系和良好的尖窝锁结关系.结论:微型种植体作为强支抗解决上牙弓前凸效果显著.%Objective: To study the effectiveness of micro - implant as a strong anchorage for dental arch protrusion. Methods: 12 patients of severe protrusion of the upper arch, were extracted the bilateral maxillary first premo-lar. Implant placed between the maxillary first molar and second premolar. X-ray skull lateral film was used to observe changes in the position of incisors and molars. Results: Arch protrusion were significantly changed after treatment. The cut ends of the maxillary incisors backed 7. 49 mm, the shaft reduced average 12. 46 °, the average forward of maxillary first molars was 0. 32 mm. Maxillary incisors before and after treatment was statistically significant (P<0. 05). The displacement of maxillary molar was not significant different before and after treatment. All patients got a good profile changes, a neutral relationship between the upper and lower molar and a good sharp junction between the lock nest. Conclusion: Micro-implant as a strong anchorage significant change the dental arch protrusion.

  5. Dental crowding in primary dentition and its relationship to arch and crown dimensions among preschool children of Davangere.

    Science.gov (United States)

    Prabhakar, A R; Ravi, G R; Kurthukoti, Ameet J; Shubha, A B

    2008-01-01

    The purpose of the present study was to evaluate dental crowding in the deciduous dentition and its relationship to the crown and the arch dimensions among preschool children of Davangere. Stratified randomized selection of one hundred, 3-4 year old healthy children with all primary teeth erupted was done and divided into two groups. One group had children with anterior crowding in both the arches while the other had spacing. Alginate impressions of the upper and lower arches were made and the study casts were obtained. The tooth and arch dimensions were determined. Mesiodistal dimensions of all the teeth were significantly larger in the crowded arch group. However, the buccolingual dimensions of the maxillary right central incisor, mandibular lateral incisors and the maxillary molars and the crown shape ratio of maxillary lateral incisors, mandibular canines and mandibular right second molar was statistically different. No significant correlation was found between the arch width and the presence of crowding of deciduous dentition. The arch depth of the spaced dentition was greater when compared to the crowded ones. The arch perimeter of the crowded arches was significantly less than the spaced arches.

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

    Science.gov (United States)

    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

  7. Techniques for aortic arch endovascular repair.

    Science.gov (United States)

    kHONGKU, 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. PMID:26940011

  8. Abnormal aortic arch morphology in Turner syndrome patients is a risk factor for hypertension.

    Science.gov (United States)

    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.

  9. Abnormal aortic arch morphology in Turner syndrome patients is a risk factor for hypertension.

    Science.gov (United States)

    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. PMID:24935217

  10. Visualization of soil arching in flexible piled embankments

    Indian Academy of Sciences (India)

    Tuğba Eskışar

    2015-10-01

    Piled embankments rely on soil arching, but, when geogrid reinforcements are used, membrane action within the reinforcement contributes to load distribution. The arching of soil in unreinforced and reinforced piled embankments is evaluated in this study. A small-scale test apparatus is used to model the settlement up to 5 mm in an embankment with four pile elements. Visual inspection of the soil settlement and soil-reinforcement interaction is important to explain the mechanism of arching. In this study, X-ray Computed Tomography (CT) method was used as a non-destructive technique. The arching of soil between the piles was observed in the case of rigid piles and in the case of flexible piles with grid type of reinforcement. The load carrying capacity increased up to 33% in the case of geogrid reinforcement, and the differential settlement decreased around 35%, proving the efficiency of piled embankments with geogrid reinforcements. It is also shown that, using X-ray CT method and visualization techniques provides a better understanding of soil behavior in a reinforced embankment with the flexible pile foundation system.

  11. Experimental study of soil arching and transfer behavior of earth pressure about sheet-pile walls%桩板墙土拱效应及土压力传递特性试验研究

    Institute of Scientific and Technical Information of China (English)

    2013-01-01

    In order to further study the soil arching behind the sheet-pile wall and analyze the earth pressure load regulation and transmission characteristic, the field large-sized test and indoor model test are carried out by monitoring research. In addition, the test results can further reveal the regularities about soil arching and load distribution. Based on the comprehension of the action mechanism about the soil arching structure, the ratio between the earth pressure on the back side of pile and pressure on the breast board is regarded as a standard which is used to assess the arching. A test model box is designed and constructed in order to load behind sheet-pile wall at a rock slope. The earth pressure cells are fixed on the dorsal surfaces of sheet and piles to test the earth pressure during future 21 days. The test results show that the earth pressure ratio increases firstly and then tends to be stable as the development of time; therefore, the time effect is relatively obvious. In addition, multiple test conditions are also designed and done to make further analysis about the relationship between the soil arching and transfer behavior of earth pressure behind sheet-pile wall. The comparative researches are done about different baffle rigidities, pile spacings, filler properties and arrangement effects of sheets, which explains the transfer behavior of load behind sheet-pile wall in the passive soil pressure state.%  为更深入地研究桩板墙背侧的土拱效应,分析其土压力荷载的作用规律及传递特性,进一步揭示桩板墙土拱效应与荷载分配之间的联系,采用现场大型试验及室内模型试验开展相关的监测研究工作。基于对土拱结构承载机制的认识,将作用于桩背侧与桩间挡板中部土压力的比值作为衡量土拱效应作用效果的直观标准。在某一自然边坡上,设计施工桩板墙堆载试验的模型槽,在挡土板与抗滑桩背侧分别安装

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

    Directory of Open Access Journals (Sweden)

    Andreas Habertheuer

    2015-01-01

    Full Text Available 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.

  13. Three-dimensional stiffness of the carpal arch.

    Science.gov (United States)

    Gabra, Joseph N; Li, Zong-Ming

    2016-01-01

    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±4.6N/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. PMID:26617368

  14. Foot medial longitudinal-arch deformation during quiet standing and gait in subjects with medial tibial stress syndrome

    DEFF Research Database (Denmark)

    Bandholm, Thomas Quaade; Boysen, Lisbeth; Haugaard, Stine;

    2008-01-01

    . Medial longitudinal-arch deformation was measured during walking gait using 3-dimensional gait analysis. Subjects with medial tibial stress syndrome demonstrated a significantly larger navicular drop (mean +/- 1 SD, 7.7 +/- 3.1 mm) and medial longitudinal-arch deformation (5.9 +/- 3.2 degrees) during...... and increased medial longitudinal-arch deformation during gait compared to healthy subjects. Medial longitudinal-arch deformation during quiet standing did not correlate with medial longitudinal-arch deformation during gait in either of the 2 groups. ACFAS Level of Clinical Evidence: 5 Udgivelsesdato: 2008/3......The objective of this study was to investigate (1) if subjects with medial tibial stress syndrome demonstrate increased navicular drop and medial longitudinal-arch deformation during quiet standing and gait compared with healthy subjects, and (2) the relationship between medial longitudinal...

  15. Predictors of long-term stability of maxillary dental arch dimensions in patients treated with a transpalatal arch followed by fixed appliances

    OpenAIRE

    Raucci, Gaetana; Elyasi, Maryam; Pachêco-Pereira, Camila; Grassia, Vincenzo; d’Apuzzo, Fabrizia; Flores-Mir, Carlos; Perillo, Letizia

    2015-01-01

    Background The aim of this retrospective study was to identify which dental and/or cephalometric variables were predictors of long-term maxillary dental arch stability in patients treated with a transpalatal arch (TPA) during the mixed dentition phase followed by full fixed appliances in the permanent dentition. Methods Thirty-six patients, treated with TPA followed up by full fixed appliances, were divided into stable and relapse groups based on the long-term presence or not of relapse. Inte...

  16. Effect of antipronation foot orthosis geometry on compression of heel and arch soft tissues

    Directory of Open Access Journals (Sweden)

    Declan Sweeney, BSc (Hon

    2016-09-01

    Full Text Available This study aimed to understand how systematic changes in arch height and two designs of heel wedging affect soft tissues under the foot. Soft tissue thickness under the heel and navicular was measured using ultrasound. Heel pad thickness was measured while subjects were standing on a flat surface and also while they were standing on an orthosis with 4 and 8 degree extrinsic wedges and 4 and 8 mm intrinsic wedges (n = 27. Arch soft tissue thickness was measured when subjects were standing and when standing on an orthosis with –6 mm, standard, and +6 mm increments in arch height (n = 25. Extrinsic and intrinsic heel wedges significantly increased soft tissue thickness under the heel compared with no orthosis. The 4 and 8 degree extrinsic wedges increased tissue thickness by 28.3% and 27.6%, respectively, while the 4 and 8 mm intrinsic wedges increased thickness by 23.0% and 14.6%, respectively. Orthotic arch height significantly affected arch soft tissue thickness. Compared with the no orthosis condition, the –6 mm, standard, and +6 mm arch heights decreased arch tissue thickness by 9.1%, 10.2%, and 11.8%, respectively. This study demonstrates that change in orthotic geometry creates different plantar soft tissue responses that we expect to affect transmission of force to underlying foot bones.

  17. 圆弧浅拱面外动力稳定性实验研究%Experimental Study on Out-of-Plane Dynamic Stability of Circular Shallow Arch

    Institute of Scientific and Technical Information of China (English)

    李康杰; 刘爱荣; 卢汉文; 禹奇才

    2015-01-01

    对称作用于拱结构的周期性荷载,一般来说,只引起拱面内的对称振动,然而在一定的条件下可能引起很大振幅的面内反对称振动以及面外对称振动,这是拱结构由于参数共振引起的动力失稳问题。本文针对圆弧浅拱平面外动力稳定问题,基于激振实验,利用 APS 系列激振器模拟拱顶单点简谐激励,采用 B&K 测振系统测定圆弧拱横向振动响应,测得结构自振模态与阻尼比,通过往返不断扫频方式获得动力不稳定域边界,并与理论结果进行了对比分析,探究了其在周期集中荷载作用下的动力侧倾失稳机理,研究结果表明:当外部激励荷载频率约为结构2倍自振频率时,结构出现激烈的横向参数共振,并且只有外激励幅值大于临界激发力时才会发生参数共振,而阻尼条件的存在影响着临界激发力的大小,外激励幅值越大,参数共振现象越容易发生,该文验证了圆弧浅拱面外动力不稳定域计算结果的准确性,研究成果为拱结构的动力稳定设计提供了一定的参考价值。%The periodic load on the arch,in general,only causes the symmetric in-plane vibration of the arch.However,under certain conditions,it can cause in-plane anti-symmetric vibration and out-of-plane symmetric vibration with large amplitude,which is so-called the instability problem of an arch structure due to the parametric resonance.Aimed at studying the out-of-plane dynamic stability problem of circular shallow arch,the experimental work is conducted trying to explore mechanism of the out-of-plane dynamic instability under concentrated periodic load.By applying APS series vibrator,the single point harmonic excitation at vault was simulated.The B&K modal testing system was used to gain the transverse vibration response of circular arch including its vibration mode shape and damping ratio.The boundaries of unsta-ble domain were

  18. A Monte Carlo study of backscattering effects in the photoelectron emission from CsI into CH$_{4}$ and Ar-CH$_{4}$ mixtures

    CERN Document Server

    Escada, J; Rachinhas, P J B M; Lopes, J A M; Santos, F P; Távora, L M N; Conde, C A N; Stauffer, A D

    2007-01-01

    Monte Carlo simulation is used to investigate photoelectron backscattering effects in the emission from a CsI photocathode into CH4 and Ar-CH4 mixtures for incident monochromatic photons with energies Eph in the range 6.8 eV to 9.8 eV (182 nm to 127 nm), and photons from a continuous VUV Hg(Ar) lamp with a spectral distribution peaked at Eph = 6.7 eV (185 nm), considering reduced applied electric fields E/N in the 0.1 Td to 40 Td range. The addition of CH4 to a noble gas efficiently increases electron transmission and drift velocity, due to vibrational excitation of the molecules at low electron energies. Results are presented for the photoelectron transmission efficiencies f, where f is the fraction of the number of photoelectrons emitted from CsI which are transmitted through the gas as compared to vacuum. The dependence of f on Eph, E/N, and mixture composition is analyzed and explained in terms of electron scattering in the different gas media, and results are compared with available measurements. Electro...

  19. Changes in lower dental arch dimensions and tooth alignment in young adults without orthodontic treatment

    OpenAIRE

    Bruno Aldo Mauad; Robson Costa Silva; Mônica Lídia Santos de Castro Aragón; Luana Farias Pontes; Newton Guerreiro da Silva Júnior; David Normando

    2015-01-01

    OBJECTIVE: The aim of this longitudinal study, comprising young adults without orthodontic treatment, was to assess spontaneous changes in lower dental arch alignment and dimensions. METHODS: Twenty pairs of dental casts of the lower arch, obtained at different time intervals, were compared. Dental casts obtained at T1 (mean age = 20.25) and T2 (mean age = 31.2) were compared by means of paired t-test (p < 0.05). RESULTS: There was significant reduction in arch dimensions: 0.43 mm for interca...

  20. CORRELATION BETWEEN DURATION OF BOTTLE-FEEDING AND DENTAL ARCH MEASUREMENT IN DECIDUOUS DENTITION

    OpenAIRE

    Meldo Mahniza; Retno Hayati; Sri Harini

    2015-01-01

    The purpose of this study was to observe the correlation between duration of bottle feeding and dental arch measurement in deciduous dentition. Duration of bottle feeding was divided into 4 groups: ≤ 24 months, 25 – 36 months, 37 – 48 months, and > 48 months. The subjects were 120 kindergarten pupils, aged 3 – 5 years old. Measurements was done on the models of maxilla and mandible with digital caliper for the width and length of dental arch and using flexible curve for dental arch circumf...

  1. Seismic vulnerability of historical arch type bridge structures in Italy

    OpenAIRE

    Qadir Bhatti, Abdul

    2009-01-01

    Italy is located on a earthquake prone area and old bridges were desinged without any seismic provision. In the years (2009), tremors were felt in Italy due to the strong earthquakes at Abruzzo, which highlight the earthquake threat to Italy. This study focuses on seismic vulnerability of arch type masonry bridge structures in Italy, designed primarily for gravity loads, when they are subjected to earthquakes. A case study has been carried out for the vulnerability study for a ...

  2. Determinant factors of Yemeni maxillary arch dimensions

    Directory of Open Access Journals (Sweden)

    Nabil Muhsen Al-Zubair

    2015-01-01

    Conclusion: 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.

  3. Impact of methodology and the use of allometric scaling on the echocardiographic assessment of the aortic root and arch: a study by the Research and Audit Sub-Committee of the British Society of Echocardiography.

    Science.gov (United States)

    Oxborough, David; Ghani, Saqib; Harkness, Allan; Lloyd, Guy; Moody, William; Ring, Liam; Sandoval, Julie; Senior, Roxy; Sheikh, Nabeel; Stout, Martin; Utomi, Victor; Willis, James; Zaidi, Abbas; Steeds, Richard

    2014-09-01

    The aim of the study is to establish the impact of 2D echocardiographic methods on absolute values for aortic root dimensions and to describe any allometric relationship to body size. We adopted a nationwide cross-sectional prospective multicentre design using images obtained from studies utilising control groups or where specific normality was being assessed. A total of 248 participants were enrolled with no history of cardiovascular disease, diabetes, hypertension or abnormal findings on echocardiography. Aortic root dimensions were measured at the annulus, the sinus of Valsalva, the sinotubular junction, the proximal ascending aorta and the aortic arch using the inner edge and leading edge methods in both diastole and systole by 2D echocardiography. All dimensions were scaled allometrically to body surface area (BSA), height and pulmonary artery diameter. For all parameters with the exception of the aortic annulus, dimensions were significantly larger in systole (P<0.05). All aortic root and arch measurements were significantly larger when measured using the leading edge method compared with the inner edge method (P<0.05). Allometric scaling provided a b exponent of BSA(0.6) in order to achieve size independence. Similarly, ratio scaling to height in subjects under the age of 40 years also produced size independence. In conclusion, the largest aortic dimensions occur in systole while using the leading edge method. Reproducibility of measurement, however, is better when assessing aortic dimensions in diastole. There is an allometric relationship to BSA and, therefore, allometric scaling in the order of BSA(0.6) provides a size-independent index that is not influenced by the age or gender. PMID:26693286

  4. Construction Points of Tied-arch Bridge across High-speed Rail:Case Study of the Construction of Tied-arch Bridge across Jihuang High-speed Rail%高速铁路桥施工要点探析--以跨绩黄高速铁路系杆拱桥施工为例

    Institute of Scientific and Technical Information of China (English)

    杨乐绪

    2015-01-01

    系杆拱桥是一种外形美观、成本较低的梁拱组合体系桥,钢管混凝土组合材料在系杆拱桥中的应用能够解决材料高强化、施工轻型化问题,有助于提高拱桥材料的稳定性、耐久性、抗腐蚀性、抗压强度等性能,施工快捷方便,造价较低,且可以缩短工期,因而得到十分广泛的应用。本文以跨绩黄高速大桥1-96m下承钢管混凝土系杆拱桥为例对其施工要点进行分析,以此得出系杆拱桥的优越性。%Tied-arch bridge is the girder and arch combination bridge with beautiful appearance and low-cost. The application of steel concrete composite materials in the tied-arch bridge can solve the problems of highly fortified material and lightweight construction, can improve the stability, durability, corrosion resistance, compressive strength and other properties of bridge material, and its construction is convenient, cost is low, and duration is short, and it has a very wide range of applications. This paper analyzes the construction points of 1-96m below bearing steel concrete tied-arch bridge across the Jihuang high-speed rail to obtain superiority of tied-arch bridge.

  5. The Role of Arch Compression and Metatarsophalangeal Joint Dynamics in Modulating Plantar Fascia Strain in Running.

    Directory of Open Access Journals (Sweden)

    Kirsty A McDonald

    Full Text Available 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.

  6. The Role of Arch Compression and Metatarsophalangeal Joint Dynamics in Modulating Plantar Fascia Strain in Running.

    Science.gov (United States)

    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.

  7. Preliminary Study on the Ultimate Seismic Capacity Evaluation of Concrete Gravity Arch Dam%混凝土重力拱坝极限抗震能力评价方法初探

    Institute of Scientific and Technical Information of China (English)

    张社荣; 王高辉; 王超

    2012-01-01

    从基于性能的抗震设防标准及理论出发,坝体某个关键性能破坏便可能影响大坝的正常运行,单一的评价准则已经不能满足对大坝极限抗震能力评估的要求。针对混凝土重力拱坝的结构特点,基于混凝土弥散裂缝模型,利用地震动超载时域分析方法,从收敛性、地震位移响应突变、塑性区贯通、坝体开裂破坏等方面,对国内某重力拱坝极限抗震能力进行了探讨和研究。研究表明,该重力拱坝的极限抗震能力为0.51g,顶拱中部是坝体相对薄弱的高地震响应区。%From the performance-based standards and the theory of seismic,the destruction of one critical performance may affect the normal operation of the dam,and a single evaluation criterion can not meet the requirement in the assessment of the ultimate aseismic capacity of dam.Based on concrete smeared crack model adopting overloaded time domain analysis method of Ground motionand considering the structural characteristics,the ultimate aseismic capacity of one domestic concrete gravity arch dam was discussed and studied from the convergence,seismic displacement response mutant,interpenetrate of the plastic zone and failure modes of cracks.The result showed that the ultimate aseismic capacity of gravity arch dam is 0.51g,and high seismic response zone locates in the central section.

  8. Study of the longitudinal vehicle distance limit of a tied arch bridge section during the loading test%系杆拱桥拱肋截面荷载试验的纵向车距限值研究

    Institute of Scientific and Technical Information of China (English)

    邱恒雅

    2013-01-01

    Bridge loading test is the most reliable method of determining its bearing capacity. It is Necessary to impose restrictions on the operate miss, in order to make the whole process of loading test more economic, safer and more reliable, and it is more difficult to control the test vehicle arrangement. This thesis takes a tied arch bridge arch-sectional loading test as a case, simulates different load efficiency and using MIDAS software when longitudinal wheelbase changes. The study shows when the longitudinal wheelbase is 2.8-5.0m, the loading efficiencies meet the design requirements. That is to say the layout error of the vehicle distance should not exceed 1.0m during actual operations.%桥梁荷载试验是确定桥梁承载能力的最可靠手段,为了使整个荷载试验过程能够更经济、安全、可靠,必须对现场实际操作误差进行一定的限制,而试验车布置时的纵向轮轴距比较难把握。本文以某系杆拱桥跨中拱肋截面荷载试验为例,在常规设计的基础上,采用MIDAS计算软件模拟计算在不同纵向车轮轴距时的荷载效率的变化情况,从而得到纵向车轮轴距一般在2.8m-5.0m才能保证荷载效率满足设计要求,也就是说实际操作时,车距布置误差不超过1.0m为宜。

  9. Comparison of arch form between ethnic Malays and Malaysian Aborigines in Peninsular Malaysia

    OpenAIRE

    Othman, Siti Adibah; 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-dimens...

  10. Evaluation of Groundwater Leakage into a Drainage Tunnel in Jinping-I Arch Dam Foundation in Southwestern China: A Case Study

    Science.gov (United States)

    Chen, Yi-Feng; Hong, Jia-Min; Zheng, Hua-Kang; Li, Yi; Hu, Ran; Zhou, Chuang-Bing

    2016-03-01

    The Jinping-I double-curvature arch dam, located in the middle reach of Yalong River and with a maximum height of 305 m, is the world's highest dam of this type that has been completed. Since the second stage of reservoir impounding, after which the reservoir water level was gradually raised by about 232 m, a significant amount of leakage was observed from the drainage holes drilled in the lowest drainage tunnel at the left bank abutment at an elevation of 1595 m a.s.l. (above sea level), with an observed maximum pressure of about 0.3 MPa. A number of investigations, including water quality analysis, digital borehole imaging, tunnel geological mapping, and in situ groundwater monitoring, were performed to examine the source of leaking, the groundwater flow paths, and the performance of the grouting curtains. By defining two objective functions using the in situ time series measurements of flow rate and hydraulic head, respectively, a multiobjective inverse modeling procedure was proposed to evaluate the permeability of the foundation rocks that was underestimated in the design stage. This procedure takes advantage of the orthogonal design, finite element forward modeling of the transient groundwater flow, artificial neural network, and non-dominated sorting genetic algorithm, hence significantly reducing the computational cost and improving the reliability of the inversed results. The geological structures that lead to the leakage were identified and the seepage flow behaviors in the dam foundation and the left bank abutment were assessed. Based on the field measurements and the inverse modeling results, the effects of the engineering treatments of the leakage event on the dam safety were analyzed. It has been demonstrated that the seepage control system is effective in lowering the groundwater level and limiting the amount of seepage in the dam foundation, and the leakage event does not pose a threat to the safety of the dam.

  11. Maxillary Arch Dimensions and Spectral Characteristics of Children with Cleft Lip and Palate Who Produce Middorsum Palatal Stops

    Science.gov (United States)

    Zajac, David J.; Cevidanes, Lucia; Shah, Sonam; Haley, Katarina L.

    2012-01-01

    Purpose: The purpose of this study was twofold: (a) to determine maxillary arch dimensions of children with repaired cleft lip and palate (CLP) who produced middorsum palatal stops and (b) to describe some spectral characteristics of middorsum palatal stops. Method: Maxillary arch width, length, and height dimensions and first spectral moments of…

  12. Signs and symptoms related to temporomandibular disorders--Follow-up of subjects with shortened and complete dental arches.

    NARCIS (Netherlands)

    Witter, D.J.; Kreulen, C.M.; Mulder, J.; Creugers, N.H.J.

    2007-01-01

    OBJECTIVE: To assess prevalence of cardinal signs and symptoms related to temporomandibular disorders (TMD) in subjects with shortened dental arches and to clarify the individual course of these signs and symptoms. METHODS: In this 9-year follow-up study, subjects with shortened dental arches (n=74)

  13. A Review of Diseases of Aortic Arch: Diagnosis by CTA

    OpenAIRE

    S. Sabouri

    2007-01-01

    The noninvasive revolution in cardiovascular imaging has altered the diagnostic algorithm for all types of acquired and congenital cardiovascular disease. CT techniques are commonly used in the diagnosis of aortic arch and its major branch vessels as well as thoracic and abdominal aortic diseases. CT angiogra-phy combines with CT scans obtained detailed in-formation on precise morphology and extent of dis-ease. Studies were performed on an MDCT unit (4row GE light speed). In infants and small...

  14. Giant aortic arch aneurysm complicating Kawasaki′s disease

    OpenAIRE

    Kaouthar Hakim; Rafik Boussada; Lilia Chaker; Fatma Ouarda

    2014-01-01

    Kawasaki disease (KD) is a common acute vasculitis in pediatric population that usually involves small- and middle-sized arteries, commonly coronary arteries. Although the incidence and natural course of coronary aneurysms after KD are well documented in studies, related reports on peripheral arterial and aortic aneurysms are scarce. We report the occurrence of a giant aortic aneurysm involving the horizontal part of aortic arch in a 28-month-old boy diagnosed with KD. This complication was m...

  15. Quasi-MLE for quadratic ARCH model with long memory

    OpenAIRE

    Grublytė, Ieva; Surgailis, Donatas; Škarnulis, Andrius

    2015-01-01

    We discuss parametric quasi-maximum likelihood estimation for quadratic ARCH process with long memory introduced in Doukhan et al. (2015) and Grublyt\\.e and \\v{S}karnulis (2015) with conditional variance given by a strictly positive quadratic form of observable stationary sequence. We prove consistency and asymptotic normality of the corresponding QMLE estimates, including the estimate of long memory parameter $0< d < 1/2$. A simulation study of empirical MSE is included.

  16. MODELING EXCHANGE RATES USING ARCH FAMILY OF MODELS

    Directory of Open Access Journals (Sweden)

    Ştefan Cristian CIUCU

    2016-06-01

    Full Text Available In this study, after a brief literature review, the RON / EURO exchange rate time series over the 03.01.2005 - 05.02.2015 time period is analyzed. After checking the stationarity of the data - ARCH, GARCH, EGARCH and TARCH models will be developed and compared. Next the best model is chosen and the serial correlation and the Jarque-Bera test are further analyzed with various conclusions being drawn.

  17. Stationarity and geometric ergodicity of a class of nonlinear ARCH models

    OpenAIRE

    Saidi, Youssef; Zakoian, Jean-Michel

    2006-01-01

    A class of nonlinear ARCH processes is introduced and studied. The existence of a strictly stationary and $\\beta$-mixing solution is established under a mild assumption on the density of the underlying independent process. We give sufficient conditions for the existence of moments. The analysis relies on Markov chain theory. The model generalizes some important features of standard ARCH models and is amenable to further analysis.

  18. Evaluation of arch width variations among different skeletal patterns in South Indian population

    OpenAIRE

    Prasad, Mandava; Kannampallil, Senny Thomas; Talapaneni, Ashok Kumar; George, Suja Ani; Shetty, Sharath Kumar

    2013-01-01

    Background: Anterior cranial base can be taken as a reference line (SN) to determine the steepness of mandibular plane. Subjects with high mandibular plane angle tend to have a long face and one with low MP-SN angle has a shorter face. Objective: This study was done to investigate if dental arch widths correlated with vertical facial types and if there are any differences in arch widths between untreated male and female adults in South Indian population. Materials and Methods: Lateral cephalo...

  19. Edentulism and shortened dental arch in Brazilian elderly from the National Survey of Oral Health 2003

    Directory of Open Access Journals (Sweden)

    Marco Túlio Freitas Ribeiro

    2011-10-01

    Full Text Available OBJECTIVE: To describe the distribution of edentulism and estimate the prevalence of functional dentition and shortened dental arch among elderly population. METHODS: A population-based epidemiological study was carried out with a sample of 5,349 respondents aged 65 to 74 years obtained from the 2002 and 2003 Brazilian Ministry of Health/Division of Oral Health survey database. The following variables were studied: gender; macroregion of residence; missing teeth; percentage that met the World Health Organization goal for oral health in the age group 65 to 74 years (50% having at least 20 natural teeth; presence of shortened dental arch; number of posterior occluding pairs of teeth. The Chi-square test assessed the association between categorical variables. The Kruskal-Wallis and Mann-Whitney tests were used to assess differences of mean between number of posterior occluding pairs teeth, macro-region and gender. RESULTS: The elderly population had an average of 5.49 teeth (SD: 7.93 with a median of 0. The proportion of completely edentulous respondents was 54.7%. Complete edentulism was 18.2% in the upper arch and 1.9% in the lower arch. The World Health Organization goal was achieved in 10% of all respondents studied. However, only 2.7% had acceptable masticatory function and aesthetics (having at least shortened dental arch and a mean number of posterior occluding pairs of 6.94 (SD=2.97. There were significant differences of the percentage of respondents that met the World Health Organization goal and presence of shortened dental arch between men and women. There were differences in shortened dental arch between macroregions. CONCLUSIONS: The Brazilian epidemiological oral health survey showed high rate of edentulism and low rate of shortened dental arch in the elderly population studied, thus suggesting significant functional and aesthetic impairment in all Brazilian macroregions especially among women.

  20. Numerical Analysis on Protecting Performance of Layered Arch Structures Subjected to Blast Loading

    Directory of Open Access Journals (Sweden)

    Dong Yongxiang

    2009-03-01

    Full Text Available Dynamic responses of layered arch structure composed of different materials subjected to blast loading are analysed by numerical simulation. The deflection, the particle velocity and the particle acceleration of the arch inwall and stress curves versus time are obtained comparing properties of blast resistance of different arch structures with the same amount of charge. The results show that the arch structure composed of foam concrete-SFRC-steel has good blast resistance. furthermore, the dynamic performance of the foam concrete-SFRC-steel composite structures is studied with different amount of charge. Additionally, coupling relationship of blast resistance and explosion charge is analysed. Comparison of numerical results with experimental results, show that they are in good agreement. This numerical analysis may provide important guidance for blastresistant design and analysis of underground structures.Defence Science Journal, 2009, 59(2, pp.131-136, DOI:http://dx.doi.org/10.14429/dsj.59.1500

  1. Correlation between maxillary central incisor crown morphology and mandibular dental arch form in normal occlusion subjects.

    Science.gov (United States)

    Paranhos, Luiz Renato; Lima, Carolina Souto; da Silva, Ricardo Henrique Alves; Daruge Júnior, Eduardo; Torres, Fernando Cesar

    2012-01-01

    The aim of this study was to evaluate the correlation between the morphology of the mandibular dental arch and the maxillary central incisor crown. Cast models from 51 Caucasian individuals, older than 15 years, with optimal occlusion, no previous orthodontic treatment, featuring 4 of the 6 keys to normal occlusion by Andrews (the first being mandatory) were observed. The models were digitalized using a 3D scanner, and images of the maxillary central incisor and mandibular dental arch were obtained. These were printed and placed in an album below pre-set models of arches and dental crowns, and distributed to 12 dental surgeons, who were asked to choose which shape was most in accordance with the models and crown presented. The Kappa test was performed to evaluate the concordance among evaluators while the chi-square test was used to verify the association between the dental arch and central incisor morphology, at a 5% significance level. The Kappa test showed moderate agreement among evaluators for both variables of this study, and the chi-square test showed no significant association between tooth shape and mandibular dental arch morphology. It may be concluded that the use of arch morphology as a diagnostic method to determine the shape of the maxillary central incisor is not appropriate. Further research is necessary to assess tooth shape using a stricter scientific basis. PMID:22666773

  2. Prediction of Collapse Scope of Deep-Buried Tunnels Using Pressure Arch Theory

    Directory of Open Access Journals (Sweden)

    Yingchao Wang

    2016-01-01

    Full Text Available Tunnel collapse remains a serious problem in practice. Effective prediction methods on tunnel collapse are necessary for tunnel engineering. In this study, systematic study on the pressure arch was presented to predict tunnel collapse. Multiple factors under different conditions were considered. First, the pressure arch was described as a certain scope in comparison with the lowest pressure arch line. Then, a deep-buried circular tunnel was selected as the investigated object. Its collapse scope was analyzed using the lowest pressure arch line. Meanwhile, the main influence from the ground stress field was considered. Different modes of ground stress fields were investigated in detail. The results indicate that the collapse scope varies with different ground stress fields. Determination on the collapse scope is strongly affected by the judgment standard of the pressure arch. Furthermore, a selected case was analyzed with the pressure arch. The area and the height of tunnel collapse were calculated with multiple factors, including ground stress field, judgment standard, and lateral pressure coefficient. Finally, selected results were compared with relevant previous researches, and reasonable results were obtained. The present results are helpful for further understanding of the tunnel collapse and could provide suitable guidance for tunnel projects.

  3. Tracheal compression due to an elongated aortic arch in patients with congenital heart disease: evaluation using multidetector-row CT

    Energy Technology Data Exchange (ETDEWEB)

    Watanabe, Noriko; Hayabuchi, Yasunobu; Inoue, Miki; Sakata, Miho; Nabo, Manal Mohamed Helmy; Nakagawa, Ryuji; Saijo, Takahiko; Kagami, Shoji [University of Tokushima, Department of Pediatrics, Tokushima (Japan)

    2009-10-15

    The airway can become obstructed as a result of compression by an elongated aortic arch. In this study we evaluated tracheal compression using multidetector-row CT in patients with congenital heart disease and an elongated aortic arch. The trachea was measured at the level of the aortic arch in 205 children and young adults and then the severity of tracheal compression was determined by measuring the tracheal diameter ratio (short axis diameter/long axis diameter). Patients were divided as follows: group I (normal aortic arch; n=166), group II (transversely running aortic arch; n=22), and group III (elongated aortic arch; n=17). From the viewpoint of the relationship of the great arteries, group II had D-malposition, and group III had L-malposition. Age, height, weight and body surface area were significantly correlated with the short and long axis diameter in group I. There was a negative correlation between tracheal diameter ratio and the physical size parameters. The tracheal diameter ratio in group III was 0.50{+-}0.13, which was significantly lower than in groups I and II (P<0.01 and 0.05, respectively). Even apparently asymptomatic patients with an elongated aortic arch can have tracheal compression. An elongated aortic arch may be a useful predictor of tracheal compression. (orig.)

  4. 中国人群个别正常牙合牙弓与基骨弓在三维空间的匹配性研究%Study on the matching of dental and basal bone arch form in three-dimensional space in individual normal occlu-sion of Chinese population

    Institute of Scientific and Technical Information of China (English)

    孙上然; 高辉; 肖丹娜

    2016-01-01

    Objective To study the matching of dental and basal bone arch form in three-dimensional space in indi-vidual normal occlusion, to provide references for the clinical treatment. Methods A total of 30 subjects with individual normal occlusion were selected and taken CBCT, the dental arch and the basal bone arch mark point coordinates were processed by mathematical method in order to establish the matching mathematical equation of maxilla and mandibular, the matching mathematical equation of the dental arch and basal bone arch by statistical analysis. Results The width and depth of maxilla and mandibular dental arch were highly correlated in canine region and the second molar region. The width and depth of basal bone arch were moderate correlated in canine region,and strong correlated in the second molar region. Conclusion Maxilla and mandibular dental arch, the basal bone arch of individual normal occlusion were highly correlated in the width and depth of canine region and the second molar region. Personalized dental arch matching mathe-matical equation was established through the regression equation.%目的 对个别正常牙合者的牙弓与基骨弓匹配性进行研究,以期指导临床治疗. 方法 选取30例个别正常牙合患者并拍摄锥形束CT,将牙弓与基骨弓标志点坐标进行数学处理,并通过统计学分析建立上下颌牙弓匹配的数学方程,以及牙弓与基骨弓的匹配数学方程. 结果 上下颌牙弓在尖牙区及第二磨牙区的宽度、深度有很强的相关性(r尖牙深度 =0. 967,r尖牙宽度 =0. 949,r磨牙深度 =0. 948,r磨牙宽度 =0. 942),上下颌基骨弓在尖牙区的深度与宽度匹配关系较弱(r上颌尖牙深度 =0. 922,r上颌尖牙宽度 =0. 701,r下颌尖牙深度 =0. 971,r下颌尖牙宽度 =0. 629),在第二磨牙区的宽度与深度有很强的相关性(r上颌磨牙深度 =0. 973,r上颌磨牙宽度 =0. 988,r下颌磨牙深度 =0. 971,r下颌磨牙宽度 =0. 976). 结论 上下颌

  5. C-arm guided closed reduction of zygomatic arch fracture

    Energy Technology Data Exchange (ETDEWEB)

    Eo, Yoon Ki; Lee, Dong Kun [College of Medicine, Wonkwang Univ., Iksan (Korea, Republic of); Kim, Jeong Sam; Jang, Young Il [Kwangyang College, Kwangyang (Korea, Republic of)

    1999-04-01

    The zygomatic arch is structurally protruded and is easily fractured. The classic management of zygomatic arch fracture has been mentioned the Keen, Lothrop, Dingman and Alling and threaded K-wire. All of the above methods have advantages and disadvantages. To minimize the disadvantages, we performed threaded K-wire for the first time using C-arm image intensifier. The subjects were 16 patients with Knight North group II (Zygomatic arch fracture). Among them the C-arm was used in 12 patients and the operator used sensitivity general method in 4 patients and confirmed the operation by mobile X-ray equipment. In conclusion, both groups were satisfied surgically and cosmetically. Using the C-arm, actual image at the time operation was clear and satisfied, the surrounding tissue damage was minimized and at was more accurately completed. The operation time was shortened by 30 to 60 minutes proving it to be an efficient method. We suggest though that further studies be needed to evaluate the radiation effect on these patients.

  6. Size-dependent bistability of an electrostatically actuated arch NEMS based on strain gradient theory

    International Nuclear Information System (INIS)

    This paper deals with the investigation of the size-dependent nature of nonlinear dynamics, in a doubly clamped shallow nano-arch actuated by spatially distributed electrostatic force. We employ strain gradient theory together with the Euler–Bernoulli and shallow arch assumptions in order to derive the nonlinear partial differential equation governing the transverse motion of the arch with mid-plane stretching effects. Using the Galerkin projection method, we derive the lumped single degree of freedom model which is then used for the study of the size effects on the nonlinear snap-through and pull-in instabilities of the arch nano-electro-mechanical-system (NEMS). Moreover, using strain gradient theory, the size-dependent bistability and fundamental frequencies of the nano-arch are scrutinized, revealing that, despite what is predicted by the classical theory, the bistability region in the parameter space of the nano-structure shrinks as the structure scales down. Also, we show that the minimum initial elevation, required for bistability, increases as the nano-arch scales down. (paper)

  7. SOFIA/FORCAST Observations of the Arched Filamentary Region in the Galactic Center

    Science.gov (United States)

    Hankins, Matthew; Lau, Ryan M.; Morris, Mark; Herter, Terry L.

    2016-06-01

    Abstract: We present 19.7, 25.2, 31.5, and 37.1 μm maps of the Thermal Arched Filament region in the Galactic Center taken with the Faint Object Infrared Camera for the SOFIA Telescope (FORCAST) with an angular resolution of 3.2-3.8". We calculate the integrated infrared luminosity of the Arched Filaments and show that they are consistent with being heated by the nearby Arches cluster. Additionally, using our observations, we infer dust temperatures (75 – 90 K) across the Arched Filaments which are remarkably consistent over large spatial scales (∼ 25 pc). We discuss the possible geometric effects needed to recreate this temperature structure. Additionally, we compare the observed morphology of the Arches in the FORCAST maps with the Paschen-α emission in the region to study what fraction of the infrared emission may be coming from dust in the HII region versus the PDR beneath it. Finally, we use Spitzer/IRAC 8 μm data to look for spatial variations in PAH abundance in the rich UV environment of the young (~2-4 Myr) and massive Arches cluster.

  8. Nonlinear simulation of arch dam cracking with mixed finite element method

    Directory of Open Access Journals (Sweden)

    Ren Hao

    2008-06-01

    Full Text Available This paper proposes a new, simple and efficient method for nonlinear simulation of arch dam cracking from the construction period to the operation period, which takes into account the arch dam construction process and temperature loads. In the calculation mesh, the contact surface of pair nodes is located at places on the arch dam where cracking is possible. A new effective iterative method, the mixed finite element method for friction-contact problems, is improved and used for nonlinear simulation of the cracking process. The forces acting on the structure are divided into two parts: external forces and contact forces. The displacement of the structure is chosen as the basic variable and the nodal contact force in the possible contact region of the local coordinate system is chosen as the iterative variable, so that the nonlinear iterative process is only limited within the possible contact surface and is much more economical. This method was used to simulate the cracking process of the Shuanghe Arch Dam in Southwest China. In order to prove the validity and accuracy of this method and to study the effect of thermal stress on arch dam cracking, three schemes were designed for calculation. Numerical results agree with actual measured data, proving that it is feasible to use this method to simulate the entire process of nonlinear arch dam cracking.

  9. 系杆拱桥吊杆节点足尺模型承载性能试验研究%Full-Scale Model Test Study of Load-Carrying Behavior of Hanger Joint of Tied Arch Bridge

    Institute of Scientific and Technical Information of China (English)

    桂水荣; 陈水生; 万水

    2013-01-01

    To study if the strength of the anchor head in anchorage zone of the hanger joint of tied arch bridge could meet the load-carrying requirements, the Shengmi Bridge in Nanchang was cited as an example, the full-scale model for the anchorage zone of the hanger joint at arch crown of the bridge was fabricated and the load-carrying capacity of the joint under the action of the de signed load was tested. The spatial finite element model of the anchorage zone was established and the theoretic values of the finite element and the measurement values of the test were comparatively analyzed. The results of the analysis show that the global strength of the double-layer steel socket of the hanger joint can meet the requirements, however, the local compressive strength values of the contact between the stiffening plates and the steel padding plate exceed the allowable values and the stiffening plates should be reinforced. The fabrication accuracy of the model has influence on the proportions of the load shared by the inner layer and outer layer of the steel socket and in the future tests of the similar kind, attention should be paid.%为研究系杆拱桥吊杆节点锚固区锚头强度是否满足受力要求,以南昌生米大桥为研究背景,制作拱顶吊杆节点锚固区的足尺模型,测试在设计荷载作用下吊杆节点承载力,并建立空间有限元模型,对比分析有限元理论值与试验实测值.研究结果表明:双层钢套筒整体强度满足要求,但加劲板与钢垫板接触位置局部抗压强度超过允许值,应对加劲板予以补强.模型试件的制作精度影响内钢管与外钢套筒分担荷载比例,在今后的类似试验过程中应予以重视.

  10. ARCHES: Advancing Research & Capacity in Hydrologic Education and Science

    Science.gov (United States)

    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

  11. Assembly and lifting of Pearl-Chain arches

    DEFF Research Database (Denmark)

    Halding, Philip Skov; Hertz, Kristian Dahl; Viebæk, N.E.;

    2015-01-01

    Pearl-Chain arches were invented at the Technical University of Denmark in cooporation with the company Abeo A/S. The system uses specially designed, pre-fabricated concrete elements that are post-tensioned together into an arch shape, which is then lifted into place. The arches can be used both ...

  12. Arch Coal focuses on its future

    International Nuclear Information System (INIS)

    Arch Coal, Inc (ACI) has emerged as the second largest US coal producer, with nearly 5000 employees producing 110 million tons of coal per year. The article discusses the company's philosophy, as stated by Steve Leer, President and CEO, and reports interviews with six other senior executives talking about policy on finances, sales, marketing, business development and operations. 8 photos

  13. 浙闽木拱桥类型学研究——以桥板苗系统为视角%Typological study on timber arch bridges in Zhe-Min provinces:with focus on bridge-deck-beam-system

    Institute of Scientific and Technical Information of China (English)

    刘妍

    2011-01-01

    The timber arch bridge in Zhejiang (Zhe) and Fujian (Min) provinces is a unique beamweaving-arch structure, and has a close genetic relationship with the Rainbow Bridge in the famous Song-dynasty painting the scene of the upriver at pure brightness festival ". By a study of typological analysis focusing on the timber structure, it is pointed out in this paper that there is an important distinction between the timber arch bridge in Zhe-Min provinces and the Rainbow Bridge over the Bian River. Throughout the development of the former, the bridge-deck-beam-system has hold a significant role, and should be seen as the third system aside from the first and second systems, viz. the tri-segment arch, and the penta-segment arch. The signification in the bridgedeck-beam-system of timber arch bridge in Zhe-Min provinces includes: functionally, it provides a gentle-sloped floor for the bridge-deck; structurally, it shares the load of the arch, and serves the structural stability; typologically, the method of the combination of the bridge-deck-beam-system and the arch system provides an important factor of depicting the development of the typology of timber bridges. And an essential character of the evolvement of the structure of timber bridges is structure addition and simplification. The simplification and stabilization are the main motivation in the evolvement of timber arch bridges.%浙闽木拱桥独特的编梁拱形结构与汴水虹桥有着密切的关系.对木拱桥结构的类型学分析结果表明,浙闽木拱桥与汴水虹桥的一个重要区别在于,在浙闽木拱桥的发展历程中,桥板苗系统自始至终占有重要的地位,可视作三节苗、五节苗体系之外的第三套体系.浙闽木拱桥桥板苗系统的重要性体现在使用功能上,可保证桥面的平缓;在结构上有效地分担了拱架荷载,并保证结构的稳定;在类型学上,桥板苗系统与编织拱系统的结合方式的多样做法,是探讨木拱桥类型学

  14. Anatomical study of aortic arch branches' variations with MRA and its significance%主动脉弓分支变异的MRA解剖学分析及其临床意义

    Institute of Scientific and Technical Information of China (English)

    李淑华; 狄玉进; 徐金法; 白敏; 陈军; 布春青

    2011-01-01

    目的:应用磁共振血管成像(MRA)分析主动脉弓分支变异的解剖学特征,探讨MRA评价主动脉弓分支变异的临床意义.方法:对1300例在我院磁共振室接受主动脉弓及其以上MRA检查的患者进行回顾性分析,分析不同类型主动脉弓分支变异的发生情况,并讨论主动脉弓分支变异的临床意义.结果:1300例患者中,形态正常者1207例(92.85%).即头臂干(BT)、左颈总动脉(LCCA)、左锁骨下动脉(LSA)从右向左分别发自主动脉弓,存在变异者93例(7.15%).共发现9种不同类型的变异.包括LCCA与BT共干发自主动脉弓43例(3.31%)·左椎动脉(LVA)于LCCA和LSA之间直接发自主动脉弓28例(2.15%).右颈总动脉(RCCA)直接发自主动脉弓伴迷走右锁骨下动脉(RSA)7例(0.54%).LCCA与RCCA共干发自主动脉弓伴迷走RSA 3例(0.23%).LCCA与BT共干,伴LVA直接发自主动脉弓5例(0.38%).LVA与LSA共干发自主动脉弓3例(0.23%).RCCA发自主动脉弓,右椎动脉(RVA)发自RCCA伴迷走RSA 2例(0.15%),LCCA,RCCA,LVA,RSA均发自主动脉弓1例(0.08%).LCCA与BT共干发自主动脉弓,LVA缺如,伴原始三叉动脉1例(0.08%).结论:主动脉弓分支变异种类繁多,MRA能很好的评价主动脉弓分支数量及其形态与开口位置,对临床有重要意义.%Objective : To evaluate the anatomical features of human aortic arch branch variations using magnetic resonance angiography (MRA) and its clinical significance, Methods;1300 patients who received aortic arch MRA were analyzed retrospectively. The aortic arch branch variations were summarized and the clinical significance was researched. Results : In 1300 cases.1207 of them ( 92. 85%) , which was a normal form, the brachiacephalic trunk ( BT) , left common carotid artery (LCCA) and left subclavian artery (LSA) originated separately from the aortic arch and 93 of them (7. 15%) were a variation form. Nine different types were found In 43 cases (3. 31%), BT and LCCA had a common trunk

  15. A quantitative method for defining high-arched palate using the Tcof1(+/-) mutant mouse as a model.

    Science.gov (United States)

    Conley, Zachary R; Hague, Molly; Kurosaka, Hiroshi; Dixon, Jill; Dixon, Michael J; Trainor, Paul A

    2016-07-15

    The palate functions as the roof of the mouth in mammals, separating the oral and nasal cavities. Its complex embryonic development and assembly poses unique susceptibilities to intrinsic and extrinsic disruptions. Such disruptions may cause failure of the developing palatal shelves to fuse along the midline resulting in a cleft. In other cases the palate may fuse at an arch, resulting in a vaulted oral cavity, termed high-arched palate. There are many models available for studying the pathogenesis of cleft palate but a relative paucity for high-arched palate. One condition exhibiting either cleft palate or high-arched palate is Treacher Collins syndrome, a congenital disorder characterized by numerous craniofacial anomalies. We quantitatively analyzed palatal perturbations in the Tcof1(+/-) mouse model of Treacher Collins syndrome, which phenocopies the condition in humans. We discovered that 46% of Tcof1(+/-) mutant embryos and new born pups exhibit either soft clefts or full clefts. In addition, 17% of Tcof1(+/-) mutants were found to exhibit high-arched palate, defined as two sigma above the corresponding wild-type population mean for height and angular based arch measurements. Furthermore, palatal shelf length and shelf width were decreased in all Tcof1(+/-) mutant embryos and pups compared to controls. Interestingly, these phenotypes were subsequently ameliorated through genetic inhibition of p53. The results of our study therefore provide a simple, reproducible and quantitative method for investigating models of high-arched palate.

  16. Earthquake safety assessment of concrete arch and gravity dams

    Institute of Scientific and Technical Information of China (English)

    Lin Gao; Hu Zhiqiang

    2005-01-01

    Based on research studies currently being carried out at Dalian University of Technology, some important aspects for the earthquake safety assessment of concrete dams are reviewed and discussed. First, the rate-dependent behavior of concrete subjected to earthquake loading is examined, emphasizing the properties of concrete under cyclic and biaxial loading conditions. Second, a modified four-parameter Hsieh-Ting-Chen viscoplastic consistency model is developed to simulate the rate-dependent behavior of concrete. The earthquake response of a 278m high arch dam is analyzed, and the results show that the strain-rate effects become noticeable in the inelastic range. Third, a more accurate non-smooth Newton algorithm for the solution of three-dimensional frictional contact problems is developed to study the joint opening effects of arch dams during strong earthquakes. Such effects on two nearly 300m high arch dams have been studied. It was found that the canyon shape has great influence on the magnitude and distribution of the joint opening along the dam axis. Fourth, the scaled boundary finite element method presented by Song and Wolf is employed to study the dam-reservoir-foundation interaction effects of concrete dams. Particular emphases were placed on the variation of foundation stiffness and the anisotropic behavior of the foundation material on the dynamic response of concrete dams. Finally, nonlinear modeling of concrete to study the damage evolution of concrete dams during strong earthquakes is discussed. An elastic-damage mechanics approach for damage prediction of concrete gravity dams is described as an example. These findings are helpful in understanding the dynamic behavior of concrete dams and promoting the improvement of seismic safety assessment methods.

  17. In-plane elastic stability of fixed parabolic shallow arches

    Institute of Scientific and Technical Information of China (English)

    CAI JianGuo; FENG Jian; CHEN Yao; HUANG LiFeng

    2009-01-01

    The nonlinear behavior of fixed parabolic shallow arches subjected to a vertical uniform load is inves-tigated to evaluate the in-plane buckling load. The virtual work principle method is used to establish the non-linear equilibrium and buckling equations. Analytical solutions for the non-linear in-plane sym-metric snap-through and antisymmetric bifurcation buckling loads are obtained. Based on the least square method, an approximation for the symmetric buckling load of fixed parabolic arch is proposedto simplify the solution process. And the relation between modified slenderness and buckling modes are discussed. Comparisons with the results of finite element analysis demonstrate that the solutions are accurate. A cable-arch structure is presented to improve the in-plane stability of parabolic arches. The comparison of buckling loads between cable-arch systems and arches only show that the effect of cables becomes more evident with the increase of arch's modified slenderness.

  18. Evolution Characteristic Analysis of Pressure-arch of a Double-arch Tunnel in Water-rich Strata

    Directory of Open Access Journals (Sweden)

    C. L. Li

    2016-03-01

    Full Text Available It is of importance to analyze the morphological characterization, the evolution process and the skewed effect of pressure-arch of a double-arch tunnel in the water-rich strata. Taking a buried depth 80 m double-arch tunnel as an example, a computational model of the double-arch tunnel was built by using FLAC3D technique. Then considering some aspects including groundwater conditions, tunnel depth, construction sequences and permeability coefficients, the coupling effect of stress field and seepage field in the pressure-arch of the double-arch tunnel was analyzed. The results show that the thickness of the pressure-arch induced by step-by-step excavation and display a step-descent skewed distribution from the left to the right of the double-arch tunnel. The permeability coefficient has a significant influence on the shape and the skewed effect of the pressure arch. The excavation of the bench method has a better arching condition than that of the expanding method. The abtained results provide a basic reference for the rock reinforcement design and safety construction of double-arch tunnels in the water-rich strata.

  19. MATHEMATICAL ANALYSIS OF DENTAL ARCH OF CHILDREN IN NORMAL OCCLUSION: A LITERATURE REVIEW

    Directory of Open Access Journals (Sweden)

    M. Abu-Hussein DDS, MScD, MSc, DPD

    2012-03-01

    Full Text Available AIM. This paper is an attempt to compare and analyze the various mathematical models for defining the dental arch curvature of children in normal occlusion based upon a review of available literature. Background. While various studies have touched upon ways to cure or prevent dental diseases and upon surgical ways for teeth reconstitution to correct teeth anomalies during childhood, a substantial literature also exists, attempting to mathematically define the dental arch of children in normal occlusion. This paper reviews these dental studies and compares them analytically. Method. The paper compares the different mathematical approaches, highlights the basic assumptions behind each model, underscores the relevancy and applicability of the same, and also lists applicable mathematical formulae. Results. Each model has been found applicable to specific research conditions, as a universal mathematical model for describing the human dental arch still eludes satisfactory definition. The models necessarily need to include the features of the dental arch, such as shape, spacing between teeth and symmetry or asymmetry, but they also need substantial improvement. Conclusions. While the paper shows that the existing models are inadequate in properly defining the human dental arch, it also acknowledges that future research based on modern imaging techniques and computeraided simulation could well succeed in deriving an allinclusive definition for the human dental curve till now eluding the experts.

  20. Children with flat feet have weaker toe grip strength than those having a normal arch

    Science.gov (United States)

    Tashiro, Yuto; Fukumoto, Takahiko; Uritani, Daisuke; Matsumoto, Daisuke; Nishiguchi, Shu; Fukutani, Naoto; Adachi, Daiki; Hotta, Takayuki; Morino, Saori; Shirooka, Hidehiko; Nozaki, Yuma; Hirata, Hinako; Yamaguchi, Moe; Aoyama, Tomoki

    2015-01-01

    [Purpose] This study investigated the relationship between toe grip strength and foot posture in children. [Subjects and Methods] A total of 619 children participated in this study. The foot posture of the participants was measured using a foot printer and toe grip strength was measured using a toe grip dynamometer. Children were classified into 3 groups; flatfoot, normal, and high arch, according to Staheli’s arch index. The differences in demographic data and toe grip strength among each foot posture group were analyzed by analysis of variance. Additionally, toe grip strength differences were analyzed by analysis of covariance, adjusted to body mass index, age, and gender. [Results] The number of participants classified as flatfoot, normal, and high arch were 110 (17.8%), 468 (75.6%), and 41 (6.6%), respectively. The toe grip strength of flatfoot children was significantly lower than in normal children, as shown by both analysis of variance and analysis of covariance. [Conclusion] A significant difference was detected in toe grip strength between the low arch and normal foot groups. Therefore, it is suggested that training to increase toe grip strength during childhood may prevent the formation of flat feet or help in the development of arch. PMID:26696732

  1. Theory and methods of global stability analysis for high arch dam

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    The global stability of high arch dam is one of the key problems in the safety study of arch dams,but no feasible method with theoretical basis is available.In this paper,based on the stability theory of mechanical system,it is demonstrated that the global failure of high arch dams belongs to a physical instability starting from local strength failure,which is the extreme point instability according to the characteristics of load-displacement curve obtained from the failure process of dam-foundation system. So the global failure of dam-foundation system should be studied with the stability theory of mechanical system.It is also pointed out that the current stability analysis methods used in engineering are consistent with the stability theory,but not established according to the mechanical system stability theory directly.A perfect method can be obtained through the study of physical disturbance equations.

  2. Study on Automatic Determination of Foot- arch Classification Parameters, Their Reliabilities and Classifying Consistency%人体足弓类型评价参数自动提取、可靠性分析及分类结果一致性研究

    Institute of Scientific and Technical Information of China (English)

    邱海; 熊树平; 孙娜; 屠晏欣

    2012-01-01

    为了实现对人体足弓类型进行科学评价和分类,本文研究了如何从二维脚印图中快速地自动提取系列足弓类型评价参数,利用实验设计的方法对系列评价参数进行了可靠性、相关性和分类结果一致性的分析.研究表明足弓系数和脚印系数比比值系数有更好可靠性,三种参数存在很好的线性相关性,通过它们进行脚型分类的结果有较好的一致性.研究结果对鞋类产品设计、运动员与士兵的选拨、足部保健等有重要的实际意义.%In order to evaluate and classify foot - arch type scientifically, this paper proposed a method to automatically determine foot - arch classification parameters from two - dimensional footprints. An experimental study was conducted to evaluate the reliabilities and correlation of each parameter and the classifying consistency. The results showed that the reliabilities of arch index and footprint index are higher than those of ratio index; each parameter does correlate with each other well and the foot - arch type classification results from three investigated parameters have good consistency. The research output could be important in several aspects such as the design of comfortable footwear products, the screening process of athletes and soldiers, and the health care of foot.

  3. Biotechnologie des archées

    OpenAIRE

    Querellou, Joel

    2010-01-01

    La majorité des enzymes utilisées dans l’industrie provient des bactéries et des levures. Mais les conditions extrêmes dans lesquelles se développent de nombreuses espèces d’archées font que leurs constituants cellulaires possèdent des propriétés et une stabilité propices à leur utilisation en biotechnologie.

  4. Recurrent Pneumonia due to Double Aortic Arch

    Directory of Open Access Journals (Sweden)

    I. Sedighi

    2012-04-01

    Full Text Available Introduction: Pneumonia is one of the most common infections during childhood. In children with recurrent bacterial pneumonia complete evaluation for underlying factors is necessary. The most common underlying diseases include: antibody deficiencies , cystic fibrosis , tracheoesophageal fistula and increased pulmonary blood flow. Vascular ring and its pressure effect is a less common cause of stridor and recurrent pneumonia. Congenital abnormalities in aortic arch and main branches which form vascular ring around esophagus and trachea with variable pressure effect cause respiratory symptoms such as stridor , wheezing and recurrent pneumoniaCase Report: A 2 year old boy was admitted in our hospital with respiratory distress and cough . Chest x-Ray demonstrated right lobar pneumonia. He had history of stridor and wheezing from neonatal period and hospitalization due to pneumonia for four times. The patient received appropriate antibiotics. Despite fever and respiratory distress improvement, wheezing continued. Review of his medical documents showed fixed pressure effect on posterior aspect of esophagus in barium swallow. In CT angiography we confirmed double aortic arch.Conclusion: Double aortic arch is one of the causes of persistant respiratory symptom and recurrent pneumonia in children for which fluoroscopic barium swallow is the first non-invasive diagnostic method.(Sci J Hamadan Univ Med Sci 2012;19(1:70-74

  5. Immediate occlusal loading of Tapered Internal Laser-Lok® implants in partial arch rehabilitations: a 24-months clinical and radiographic study

    OpenAIRE

    Grande, M.; A. Ceccherini; Serra, M.; L. Bava; D. Farronato; V. Iorio Siciliano; Guarnieri, R

    2013-01-01

    Aim The purpose of this 2 year prospective clinical study was to clinically and radiographically evaluate an implant with laser microtextured collar surface placed for immediate loading of fixed prostheses in cases of partial posterior maxillary and/or mandibular edentulism.Materials and methods Thirty-five partially edentulous patients who needed implant treatment and met inclusion criterias were consecutively enrolled at different study-centers in Italy. A total of 107 Tapered Internal Lase...

  6. The Origin of the Dust Arch in the Halo of NGC 4631 An Expanding Superbubble?

    CERN Document Server

    Taylor, C L; Taylor, Christopher L.

    2003-01-01

    We study the nature and the origin of the dust arch in the halo of the edge-on galaxy NGC 4631 detected by Neininger & Dumke (1999). We present CO observations made using the new On-The-Fly mapping mode with the FCRAO 14m telescope, and find no evidence for CO emission associated with the dust arch. Our examination of previously published HI data shows that if previous assumptions about the dust temperature and gas/dust ratio are correct, then there must be molecular gas associated with the arch, below our detection threshold. If this is true, then the molecular mass associated with the dust arch is between 1.5 x 10^8 M(sun)and 9.7 x 10^8 M(sun), and likely towards the low end of the range. A consequence of this is that the maximum allowed value for the CO-to-H_2 conversion factor is 6.5 times the Galactic value, but most likely closer to the Galactic value. The kinematics of the HI apparently associated with the dust arch reveal that the gas here is not part of an expanding shell or outflow, but is inste...

  7. Segmented arch or continuous arch technique? A rational approach

    Directory of Open Access Journals (Sweden)

    Sergei Godeiro Fernandes Rabelo Caldas

    2014-04-01

    Full Text Available This study aims at revising the biomechanical principles of the segmented archwire technique as well as describing the clinical conditions in which the rational use of scientific biomechanics is essential to optimize orthodontic treatment and reduce the side effects produced by the straight wire technique.

  8. Neural Network in Developing Software for Indentifying Arch Form

    Directory of Open Access Journals (Sweden)

    Johan Arief Budiman

    2013-06-01

    Full Text Available The treatment of Class I malocclusion treatment is to arrange the teeth position in a good arch form. Archform consists of tooth size and arch dimension (intercanine width, canine depth, intermolar width, molardepth. Several ways are developed to describe arch form. A lot of methods usedto describe arch formqualitatively.The objectiveofthis studyistodevelop qualitative arch form diagnostic references usingartificial neural network from pre-post treatment dental cast scanning result. Pre-post orthodontictreatment dental casts (1990-2006 from Post Graduate Clinic Faculty of Dentistry University of Indonesiaand 3 other orthodontistswere gathered andscanned.Dataweremeasured usingImage Toolandanalyzedusing Stata 9.ANOVA was used to compare arch forms (square, oval, tapered and gender (male andfemale, with each component of arch dimension upper and lowerjaw, before and after treatment; and alsoarch perimeter to kinds of treatmentThe results were compiled todeterminevariables inbuildingthesoftware for analyzing arch form qualitatively.The data from190 pre-post orthodontic treatment dentalcasts consisted of42 male (22.1% and 148 female (77.9% treated without extraction (32.63%,4Premolars extraction (48.42%, Upper Premolars extraction (11.05%, atypical extraction (7.90%.Gender and allvariables from pre treatment did not influence arch form, except kinds of treatment.Therefore, only post treatment data are included for arch form analysis. The shape of arch form (square,oval and tapered can be described qualitatively by software using artificial neural network.This softwarecoulddescribe arch form with the accuracy of 76.3158%.This studyconcludedthatIntercanine width,Canine depth, Intermolar width, and molar depth were variables that influencedarch form. A softwareusing artificial neural network to describe arch formqualitatively couldbe used for diagnostic reference toClass I malocclusion orthodontic post treatment.

  9. An Investigation into the Response of GFRP-Reinforced Glue-Laminated Tudor Arches

    Directory of Open Access Journals (Sweden)

    S. Alshurafa

    2012-01-01

    Full Text Available This paper presents the results of an experimental and computational investigation tailored to examine the response of glass fiber-reinforced-plastic-(GFRP- reinforced glue-laminated curved beams and arches. The main objective was to ascertain the viability of GFRP as an effective reinforcement for enhancing the load carrying capacity and stiffness of such curved structures. The study included optimization of the length and thickness of the GFRP reinforcement. In doing so, first a parametric finite element study was conducted to evaluate the influence of unidirectional GFRP reinforcement applied onto the arch using eleven possible configurations and different thicknesses. Subsequently, an experimental investigation was conducted to verify the results established by the finite element method as well as the integrity of actual GFRP-reinforced glue-laminated curved structures. The results indicate that GFRP can be considered as an effective and economically viable solution for strengthening and stiffening glulam arches, without adding any appreciable weight to the structure.

  10. Immediate occlusal loading of Tapered Internal Laser-Lok® implants in partial arch rehabilitations: a 24-months clinical and radiographic study

    Directory of Open Access Journals (Sweden)

    M. Grande

    2013-10-01

    Full Text Available Aim The purpose of this 2 year prospective clinical study was to clinically and radiographically evaluate an implant with laser microtextured collar surface placed for immediate loading of fixed prostheses in cases of partial posterior maxillary and/or mandibular edentulism.Materials and methods Thirty-five partially edentulous patients who needed implant treatment and met inclusion criterias were consecutively enrolled at different study-centers in Italy. A total of 107 Tapered Internal Laser-Lok® implants (49 maxillary and 58 mandibular were placed and immediately loaded. All provisional constructions were delivered within 1 hour, and the final constructions placed after 4 months. A total of 107 Tapered Internal Laser-Lok implants (49 maxillary and 58 mandibular were placed and immediately loaded. All provisional restorations were delivered within 1 hour, and the final prosthesis placed after 4 months. A total of 32 prosthetic restorations, consisting of 10 two- units, 12 three-units, and 10 four-units fixed partial dentures were evaluated. Clinical and radiographic outcomes were monitored at follow-up examinations scheduled 6, 12, 24 months after implants placement.Results Five implants were lost after loading (3 implants in a two-unit maxillary restorations, 1 implant in a two-unit mandibular restorations, and 1 implant in three-unit maxillary restorationsgiving a survival rate of 95.4% after 24 months. Mean crestal bone loss at 6, 12, and 24 months after implant insertion was 0.42 +/- 1.1 mm, 0.52 +/- 0.9 mm, and 0.66 +/- 1.3 mm, respectively.Conclusion Although limited bytheshort follow-up, immediate function with Tapered Internal Laser-Lok® implants seems to be a viable option to treat partially edentulous patients.

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

    OpenAIRE

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

    2016-01-01

    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 polynomia...

  12. Unilateral hyperplasia of the left posterior arch and associated vertebral schisis at C6 level

    Energy Technology Data Exchange (ETDEWEB)

    Esposito, Giuseppe; Bonis, Pasquale de; Tamburrini, Gianpiero; Massimi, Luca; Rocco, Concezio di [Catholic University, School of Medicine, Department of Pediatric Neurosurgery, Rome (Italy); Byvaltsev, Vadim [Irkutsk Railway Clinical Hospital, Department of Neurosurgery, Irkutsk (Russian Federation); Leone, Antonio [Catholic University, School of Medicine, Department of Bioimaging and Radiological Sciences, Rome (Italy)

    2009-12-15

    We report on a 5-year-old girl with unilateral hyperplasia of the left posterior arch of C6 associated with spina bifida occulta at the same level. Anteroposterior and lateral radiographs of the cervical spine showed hypertrophy of the left lamina as well as overgrowth and elongation of the left spinous process of the sixth cervical vertebra. Computed tomography (CT) examination better depicted this congenital variant and clearly showed the associated schisis of the posterior arch at the same level. Magnetic resonance (MR) imaging examination ruled out other spinal anomalies. The neck pain, the young age of the patient and the local aesthetic abnormality contributed to the surgical indication. To the best of our knowledge, this is the first case in the English literature of unilateral hyperplasia of a posterior cervical arch. Only one previous study has reported a similar congenital anomaly, but it was limited to the left side of the spinous process. (orig.)

  13. The origin and significance of secondary flows in the aortic arch.

    Science.gov (United States)

    Black, M M; Hose, D R; Lawford, P V

    1995-01-01

    This paper comprises a study of the secondary flow patterns that can develop in the human aortic arch. Clinical evidence of these secondary flows has been obtained by Kilner et al. using magnetic resonance velocity mapping techniques. Some of their results are presented for comparison in this paper. Four difference parametric models of the aortic arch have been analysed using computational fluid dynamic techniques. Both steady and transient flow conditions have been considered and two different commercially available software packages were used, namely FIDAP and FLOTRAN. A satisfactory comparison of the theoretical analysis with the results, both in vivo and in vitro, obtained by Kilner et al. for their out-of-plane inlet model was found. The theoretical analysis can now be extended to analyse the effect of different configurations and orientations of artificial aortic valves on the resulting aortic arch flow patterns.

  14. Unilateral hyperplasia of the left posterior arch and associated vertebral schisis at C6 level

    International Nuclear Information System (INIS)

    We report on a 5-year-old girl with unilateral hyperplasia of the left posterior arch of C6 associated with spina bifida occulta at the same level. Anteroposterior and lateral radiographs of the cervical spine showed hypertrophy of the left lamina as well as overgrowth and elongation of the left spinous process of the sixth cervical vertebra. Computed tomography (CT) examination better depicted this congenital variant and clearly showed the associated schisis of the posterior arch at the same level. Magnetic resonance (MR) imaging examination ruled out other spinal anomalies. The neck pain, the young age of the patient and the local aesthetic abnormality contributed to the surgical indication. To the best of our knowledge, this is the first case in the English literature of unilateral hyperplasia of a posterior cervical arch. Only one previous study has reported a similar congenital anomaly, but it was limited to the left side of the spinous process. (orig.)

  15. Numerical simulation of damage in high arch dam due to earthquake

    Institute of Scientific and Technical Information of China (English)

    Hong ZHONG; Gao LIN; Hongjun LI

    2009-01-01

    Based on the assumption that concrete is macroscopic homogeneous, the cracking evolution process and damage mode of high arch dams are studied in consideration of the heterogeneity of concrete in mesos-cale. The bilinear damage evolution model and the damage evolution model expressed in power function with descending section are adopted to combine with the Mohr-Coulomb criterion with tension cut-off to investigate the crack development and fracture mode of high arch dams under the action of an earthquake. The analysis result of a high arch dam in China under design shows that cracks that take place in concrete are caused by excessive tensile stress. The cracks initiate at the middle of the dam top and distribute at the upper half of the dam while the rest of the parts remain intact. This conclusion agrees with the model test result.

  16. FLOOD DISCHARGE AND ENERGY DISSIPATION BY JETS FROM OUTLETS IN HIGH ARCH DAM

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In this thesis, the downstream local rock-bed scour by multiple layered jets and by the collision of water jets in vertical and transverse directions were studied and the stability of the inverted arch cushion pool were analyzed. The velocity distribution of an aerated jet running dwon in the pool is obtained, a new method to calculate the scour depth by multiple layered jets and by the collision of water jets was proposed, and a muthematical model to forecast the critical downstream depth as a slab with various specific gravity destructions was established. The results were verified by experimental research on the hydrodynamic pressure produced at gaps of the inverted arch type of wate cushion pool and by using an advanced measurement and the imitation method experiments on forces at both arch spandrels were carried out to find their characteristics.

  17. Arch height change during sit-to-stand: an alternative for the navicular drop test

    Directory of Open Access Journals (Sweden)

    McPoil Thomas G

    2008-07-01

    Full Text Available Abstract Background A study was conducted to determine the reliability and validity of a new foot mobility assessment method that utilizes digital images to measure the change in dorsal arch height measured at 50% of the length of the foot during the Sit-to-Stand test. Methods Two hundred – seventy five healthy participants participated in the study. The medial aspect of each foot was photographed with a digital camera while each participant stood with 50% body weight on each foot as well as in sitting for a non-weight bearing image. The dorsal arch height was measured at 50% of the total length of the foot on both weight bearing and non-weight bearing images to determine the change in dorsal arch height. The reliability and validity of the measurements were then determined. Results The mean difference in dorsal arch height between non-weight bearing and weight bearing was 10 millimeters. The change in arch height during the Sit-to-Stand test was shown to have good to high levels of intra- and inter-reliability as well as validity using x-rays as the criterion measure. Conclusion While the navicular drop test has been widely used as a clinical method to assess foot mobility, poor levels of inter-rater reliability have been reported. The results of the current study suggest that the change in dorsal arch height during the Sit-to-Stand test offers the clinician a reliable and valid alternative to the navicular drop test.

  18. In-plane elastic stability of fixed parabolic shallow arches

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The nonlinear behavior of fixed parabolic shallow arches subjected to a vertical uniform load is inves- tigated to evaluate the in-plane buckling load. The virtual work principle method is used to establish the non-linear equilibrium and buckling equations. Analytical solutions for the non-linear in-plane sym- metric snap-through and antisymmetric bifurcation buckling loads are obtained. Based on the least square method, an approximation for the symmetric buckling load of fixed parabolic arch is proposed to simplify the solution process. And the relation between modified slenderness and buckling modes are discussed. Comparisons with the results of finite element analysis demonstrate that the solutions are accurate. A cable-arch structure is presented to improve the in-plane stability of parabolic arches. The comparison of buckling loads between cable-arch systems and arches only show that the effect of cables becomes more evident with the increase of arch’s modified slenderness.

  19. CORRECTION OF ALVEOLAR ARCH MALALIGNMENT AFTER TOTAL CORRECTION IN UNILATERAL AND BILATERAL GR III CLEFTS

    Directory of Open Access Journals (Sweden)

    Mohana Rao

    2015-06-01

    Full Text Available AIMS AND OBJECTIVES: Aim of this study is to document and analyse the pre - operative and postoperative alveolar arch impressions . MATERIALS AND METHODS: 20 cases of both unilateral and bilateral GR III clefts selected for this study. These pati ents were operated at the age of not less than 9 months, preferably below the age of 18 months. Below the age of 9 months general condition of these children may not cope up the duration of general anesthesia and amount of surgical trauma. After intubating the patient preoperatively, with the help of custom made metal arch plates, at first, Medical grade Alginate material with optimal hydration used to get negative impression, from these , positive impressions were obtained by the use of optimally hydrated m edical grade stone powder routinely used by dental surgeons. These positive impressions along with negative impression s and metal plates allowed to settle down for 10 hours undisturbed, after that positive impressions retrieved carefully without breaking a nd stored for analysis. Similarly postoperative impressions were taken after a gap of 2 years in the same manner like that of pre - operative ones under general anesthesia. Both impressions w ere compared and analysis was done regarding alveolar arch malalign ment, asymmetry and arch collapse correction. RESULTS & CONCLUSION: The status of the alveolar arch after single stage operation for cleft lip and palate in the unilateral cleft was much improved and there was considerable correction of the arch collapse a s well; in the bilateral cleft the correction of the premaxillary protrusion was better appreciated than the degree of correction of the alveolar gap.

  20. Carpal arch and median nerve changes during radioulnar wrist compression in carpal tunnel syndrome patients.

    Science.gov (United States)

    Marquardt, Tamara L; Evans, Peter J; Seitz, William H; Li, Zong-Ming

    2016-07-01

    The purpose of this study was to investigate the morphological changes of the carpal arch and median nerve during the application of radiounlarly directed compressive force across the wrist in patients with carpal tunnel syndrome. Radioulnar compressive forces of 10 N and 20 N were applied at the distal level of the carpal tunnel in 10 female patients diagnosed with carpal tunnel syndrome. Immediately prior to force application and after 3 min of application, ultrasound images of the distal carpal tunnel were obtained. It was found that applying force across the wrist decreased the carpal arch width (p 1234-1240, 2016. PMID:26662276

  1. Median deficiency in the posterior arch of the atlas vertebra: a case report

    Directory of Open Access Journals (Sweden)

    Kaushal P

    2011-04-01

    Full Text Available Isolated cases of partial agenesis of atlas were initially considered benign variations, without any clinical or pathological significance. However, there is increasing evidence that neurological symptoms may occur even after minor cervical trauma in subjects with defects in the posterior arch of the atlas. The present case study describes a rare case of median deficiency in the posterior arch of atlas vertebra. The knowledge of this benign variation is crucial as it may aid clinicians in correct management of subjects presenting with resolution of symptoms and avoid excessive investigations.

  2. Normal azygos arch: retrotracheal visualization on frontal chest tomograms.

    Science.gov (United States)

    Austin, J H; Thorsen, M K

    1981-12-01

    Anteroposterior, linear tomograms of 78 adult subjects in the supine position revealed visualization of pleural reflections off the retrotracheal part of the normal azygos arch in 38 (49%). The course of the arch varied by about 3 cm. Five distinct patterns were found, mainly depending on the course of the inferior margin of the arch. The inferior margin varied from relatively superior retrotracheal positions to intermediate positions appearing to intersect the carina, to relatively inferior and right-sided positions posterior to the proximal right main bronchus. Recognition of these normal variations of the azygos arch should serve to differentiate them from abnormalities in this region. PMID:6976093

  3. Normal azygos arch: retrotracheal visualization on frontal chest tomograms

    International Nuclear Information System (INIS)

    Anteroposterior, linear tomograms of 78 adult subjects in the supine position revealed visualization of pleural reflections off the retrotracheal part of the normal azygos arch in 38 (49%). The course of the arch varied by about 3 cm. Five distinct patterns were found, mainly depending on the course of the inferior margin of the arch. The inferior margin varied from relatively superior retrotracheal positions to intermediate positions appearing to intersect the carina, to relatively inferior and right-sided positions posterior to the proximal right main bronchus. Recognition of these normal variations of the azygos arch should serve to differentiate them from abnormalities in this region

  4. Normal azygos arch: retrotracheal visualization on frontal chest tomograms

    Energy Technology Data Exchange (ETDEWEB)

    Austin, J.H.M. (Columbia-Presbyterian Medical Center, New York); Thorsen, M.K.

    1981-12-01

    Anteroposterior, linear tomograms of 78 adult subjects in the supine position revealed visualization of pleural reflections off the retrotracheal part of the normal azygos arch in 38 (49%). The course of the arch varied by about 3 cm. Five distinct patterns were found, mainly depending on the course of the inferior margin of the arch. The inferior margin varied from relatively superior retrotracheal positions to intermediate positions appearing to intersect the carina, to relatively inferior and right-sided positions posterior to the proximal right main bronchus. Recognition of these normal variations of the azygos arch should serve to differentiate them from abnormalities in this region.

  5. Classification of the height and flexibility of the medial longitudinal arch of the foot

    Directory of Open Access Journals (Sweden)

    Nilsson Mette

    2012-02-01

    Full Text Available Abstract Background The risk of developing injuries during standing work may vary between persons with different foot types. High arched and low arched feet, as well as rigid and flexible feet, are considered to have different injury profiles, while those with normal arches may sustain fewer injuries. However, the cut-off values for maximum values (subtalar position during weight-bearing and range of motion (ROM values (difference between subtalar neutral and subtalar resting position in a weight-bearing condition for the medial longitudinal arch (MLA are largely unknown. The purpose of this study was to identify cut-off values for maximum values and ROM of the MLA of the foot during static tests and to identify factors influencing foot posture. Methods The participants consisted of 254 volunteers from Central and Northern Denmark (198 m/56 f; age 39.0 ± 11.7 years; BMI 27.3 ± 4.7 kg/m2. Navicular height (NH, longitudinal arch angle (LAA and Feiss line (FL were measured for either the left or the right foot in a subtalar neutral position and subtalar resting position. Maximum values and ROM were calculated for each test. The 95% and 68% prediction intervals were used as cut-off limits. Multiple regression analysis was used to detect influencing factors on foot posture. Results The 68% cut-off values for maximum MLA values and MLA ROM for NH were 3.6 to 5.5 cm and 0.6 to 1.8 cm, respectively, without taking into account the influence of other variables. Normal maximum LAA values were between 131 and 152° and normal LAA ROM was between -1 and 13°. Normal maximum FL values were between -2.6 and -1.2 cm and normal FL ROM was between -0.1 and 0.9 cm. Results from the multivariate linear regression revealed an association between foot size with FL, LAA, and navicular drop. Conclusions The cut-off values presented in this study can be used to categorize people performing standing work into groups of different foot arch types. The results of this

  6. The association between dental arch dimensions and occurrence of Finnish dental consonant misarticulations in cleft lip/palate children.

    Science.gov (United States)

    Laitinen, J; Ranta, R; Pulkkinen, J; Haapanen, M L

    1998-10-01

    The aim of this study was to examine whether maxillary and mandibular dental arch width, length, and palatal height dimensions are associated with the occurrence of misarticulations (phonetic or phonologic errors) in the dental consonants /r/, /s/, and /1/ in different cleft types and sexes. The subjects were 263 (109 girls, 154 boys) 6-year-old Finnish-speaking non-syndromic children with isolated cleft palate (CP, n=79), deft lip/alveolus (CL(A), n=77), unilateral (UCLP, n=80), and bilateral (BCLP, n=27) cleft lip and palate. Dental plaster casts were measured by two authors using the technique of Moorrees, and auditive speech was analyzed with high reliability by two speech pathologists. The results showed that the occurrence of misarticulations increased and dental arch dimensions decreased with the severity of the cleft. Narrower and shorter maxillary arches as well as shallower palates were related to problems with the studied dental consonants. Mandibular arch dimensions were not related to the misarticulations. However, statistical analysis did not reveal significant differences in dental arch dimensions between subjects with and without misarticulations when they were compared separately for different cleft types. The etiology of clefting per se--isolated deft palate versus cleft lip with or without deft palate--did not seem to explain the associations between dental arch dimensions and the studied misarticulations.

  7. Building problem solving environments with the arches framework

    Energy Technology Data Exchange (ETDEWEB)

    Debardeleben, Nathan [Los Alamos National Laboratory; Sass, Ron [U NORTH CAROLINA; Stanzione, Jr., Daniel [ASU; Ligon, Ill, Walter [CLEMSON UNIV

    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.

  8. Design and construction of prestressed arch using plastic shoppers waste

    Directory of Open Access Journals (Sweden)

    Ali Khan, S.

    2012-12-01

    Full Text Available Since the development of plastic in the last century, being versitile it has become very popular for diversified uses. The problem appears when these plastics, particularly shoppers are disposed as waste. The current reuse and recycling rates for the plastic shoppers waste are very low. Construction Industry has a great potential for the reuse of shoppers waste. Shoppers waste has been compressed to fabricate compressed shoppers waste (CSW blocks. This study is related to an innovative reuse of CSW-blocks for the construction of prestressed structural arch. This paper is dedicated to the design and construction of structural arch using shoppers waste as a material.

    Desde su desarrollo durante el siglo pasado y debido a su versatilidad, el plástico se ha hecho ubicuo en la sociedad actual. Los problemas surgen cuando este material, sobre todo cuando conforma bienes de consumo, se desecha. Actualmente, los índices de valorización y reciclado de residuos plásticos de origen doméstico son muy bajos. El sector de la construcción tiene una enorme potencial para reutilizar este tipo de residuos, que se pueden comprimir para fabricar bloques. Este artículo presenta un uso innovador de los bloques de residuos plásticos: la construcción de un arco estructural pretesado. Describe el proyecto y la ejecución de un arco estructural construido con estos materiales de desecho.

  9. THE EVOLUTION OF PROTOPLANETARY DISKS IN THE ARCHES CLUSTER

    International Nuclear Information System (INIS)

    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.

  10. Deformation reinforcement theory and its application to high arch dams

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In this paper,the deformation reinforcement theory(DRT) proposed by the authors is elaborated with a new definition of instability that an elasto-plastic structure is not stable if it cannot satisfy simultaneously equilibrium condition,kinematical admissibility and constitutive equations under the prescribed loading.Starting from the definition,a proof is established to the principle of minimum plastic complementary energy for failured structures.It is revealed that the principle of mini-mum plastic complementary energy results in relaxed constitutive equations,especially,yield conditions.It is demonstrated with case studies that many key issues in arch dam design,e.g.,global stability,dam-toe reinforcement,dam-toe cracking,dam-abut-ment reinforcement,can be well solved within the framework of the deformation reinforcement theory.The structural global stability can be described by the curve of the plastic complementary energy vs overloading factor.The unbalanced-forces obtained by elasto-plastic FEM can be used as the basis of analysis of global stability,dam-heel cracking,dam-toe anchorage and reinforcement of faults of high arch dams and their foundations.

  11. Estimation and asymptotic inference in the first order AR-ARCH model

    DEFF Research Database (Denmark)

    Lange, Theis; Rahbek, Anders; Jensen, Søren Tolver

    2011-01-01

    This article studies asymptotic properties of the quasi-maximum likelihood estimator (QMLE) for the parameters in the autoregressive (AR) model with autoregressive conditional heteroskedastic (ARCH) errors. A modified QMLE (MQMLE) is also studied. This estimator is based on truncation of individual...

  12. Correlation analysis of craniomandibular index and gothic arch tracing in patients with craniomandibular disorders

    Directory of Open Access Journals (Sweden)

    Todić Jelena

    2011-01-01

    Full Text Available Background/Aim. Complex etiology and symptomatology of craniomandibular dysfunction make the diagnosing and therapy of this disorder more difficult. The aim of this work was to assess the value of clinical and instrumental functional analyses in diagnosing of this type of disorders. Methods. In this study 200 subjects were examined, 15 with temporomandibular joint disorder. They were subjected to clinical functional analysis (Fricton-Shiffman and instrumental functional analysis by using the method of gothic arch. The parameters of the gothic arch records were analyzed and subsequently compared among the subjects of the observed groups. Results. In the examined group of the population 7.5% of them were with craniomandibular dysfunction. The most frequent symptoms were sound in temporomandibular joint, painful sensitivity of the muscles on palpation and lateral turning of the lower jaw while opening the mouth. By analyzing the gothic arch records and comparing the obtained values between the observed groups it was assessed that: lateral and protrusion movements, lateral amplitude and the size of gothic arch were much bigger in the healthy subjects, and latero-lateral asymmetry was larger in the sick subjects. Latero-lateral dislocation of apex was recorded only in the sick subjects with average values of 0.22 ± 0.130 mm. The correlation between the values of Fricton-Shiffman craniomandibular index and the parameters of the gothic arch records and latero-lateral amplitude and dislocation of apex records were established by correlative statistical analysis. Conclusion. Functional analysis of orofacial system and instrumental analysis of lower jaw movements (gothic arch method can be recommended as precise and simple methods in diagnosing craniomandibular dysfunctions.

  13. The relationships between foot arch volumes and dynamic plantar pressure during midstance of walking in preschool children.

    Directory of Open Access Journals (Sweden)

    Hsun-Wen Chang

    Full Text Available OBJECTIVES: The purpose of this study was to examine the correlation between the foot arch volume measured from static positions and the plantar pressure distribution during walking. METHODS: A total of 27 children, two to six years of age, were included in this study. Measurements of static foot posture were obtained, including navicular height and foot arch volume in sitting and standing positions. Plantar pressure, force and contact areas under ten different regions of the foot were obtained during walking. RESULTS: The foot arch index was correlated (r = 0.32 with the pressure difference under the midfoot during the foot flat phase. The navicular heights and foot arch volumes in sitting and standing positions were correlated with the mean forces and pressures under the first (r = -0.296∼-0.355 and second metatarsals (r = -0.335∼-0.504 and midfoot (r = -0.331∼-0.496 during the stance phase of walking. The contact areas under the foot were correlated with the foot arch parameters, except for the area under the midfoot. CONCLUSIONS: The foot arch index measured in a static position could be a functional index to predict the dynamic foot functions when walking. The foot arch is a factor which will influence the pressure distribution under the foot. Children with a lower foot arch demonstrated higher mean pressure and force under the medial forefoot and midfoot, and lower contact areas under the foot, except for the midfoot region. Therefore, children with flatfoot may shift their body weight to a more medial foot position when walking, and could be at a higher risk of soft tissue injury in this area.

  14. Thin-plate spline analysis of arch form in a Southern European population with an ideal natural occlusion.

    Science.gov (United States)

    Camporesi, Matteo; Franchi, Lorenzo; Baccetti, Tiziano; Antonini, Antonino

    2006-04-01

    The purpose of the present study was to identify the mean configuration of the clinical arch form in a sample of Southern European subjects with ideal natural occlusion by means of Procrustes analysis, and to compare the identified configuration with 10 commercially produced arch forms by means of thin-plate spline (TPS) analysis. The sample comprised the study casts of 50 subjects (26 males and 24 females). The mean age of the sample was 26 years +/- 4 years. All subjects were young Caucasian adults of Southern European ancestry, and presented with an ideal natural occlusion. The three-dimensional (3D) co-ordinates of all dental points (facial axis points) were digitized using a 3D electromagnetic digitizer. The morphometric technique of TPS analysis with permutation tests was used to compare the configurations of landmarks in the various specimens. No sexual dimorphism was found for either upper or lower arch forms when the shape of the arches was assessed independently from size. The commercially available arch form that showed the least, though statistically significant, shape difference with respect to the average calculated configuration was the Brader arch form. PMID:16115828

  15. 正畸弓丝形态的研究进展%Research prowess on the arch form in orthodontics

    Institute of Scientific and Technical Information of China (English)

    张林; 段沛沛

    2012-01-01

    在正畸临床治疗过程中,弓丝形态的设计和应用至关重要,其不仅关系到正畸治疗效果,而且对治疗周期、治疗后的稳定性等有着重要影响.不正确的弓丝形态的应用容易造成牙弓、牙槽弓、基骨弓形态的不一致,从而可能引起口颌肌系统功能不协调,容易导致复发.很多学者对怎样确定正确的正畸弓丝形态进行了大量研究,包括寻找适合大多数患者的理想弓形以及适合于个别患者的个体(牙合)弓形.本文将对标准理想牙弓形态以及个体(牙合)牙弓形态的拟合理论、应用现状以及优缺点作一综述.%The size and shape of the arch wire used in orthodontic treatment have considerable implications on the treatment effect, treatment cycle and the stability of the dentition. Using improper arch wire may cause mismatching of shape among dental arch, alveolar arch and basal arch, affecting the equilibrium of teeth between tongue and circumoral muscle forces. This always leads to relapse. Arch form relative to orthodontic therapy has been examined in various studies, including the classic and individual arch wire form. The aim of the article is to give a review on the relevant researches about the combination of the classic and individual arch wire form. The theory, practical applications and problems of these methods are described.

  16. Elastic energy within the human plantar aponeurosis contributes to arch shortening during the push-off phase of running.

    Science.gov (United States)

    Wager, Justin C; Challis, John H

    2016-03-21

    During locomotion, the lower limb tendons undergo stretch and recoil, functioning like springs that recycle energy with each step. Cadaveric testing has demonstrated that the arch of the foot operates in this capacity during simple loading, yet it remains unclear whether this function exists during locomotion. In this study, one of the arch׳s passive elastic tissues (the plantar aponeurosis; PA) was investigated to glean insights about it and the entire arch of the foot during running. Subject specific computer models of the foot were driven using the kinematics of eight subjects running at 3.1m/s using two initial contact patterns (rearfoot and non-rearfoot). These models were used to estimate PA strain, force, and elastic energy storage during the stance phase. To examine the release of stored energy, the foot joint moments, powers, and work created by the PA were computed. Mean elastic energy stored in the PA was 3.1±1.6J, which was comparable to in situ testing values. Changes to the initial contact pattern did not change elastic energy storage or late stance PA function, but did alter PA pre-tensioning and function during early stance. In both initial contact patterns conditions, the PA power was positive during late stance, which reveals that the release of the stored elastic energy assists with shortening of the arch during push-off. As the PA is just one of the arch׳s passive elastic tissues, the entire arch may store additional energy and impact the metabolic cost of running.

  17. The seismic response of concrete arch bridges (with focus on the Bixby Creek bridge Carmel, California)

    Energy Technology Data Exchange (ETDEWEB)

    Hoehler, M; McCallen, D; Noble, C

    1999-06-01

    The analysis, and subsequent retrofit, of concrete arch bridges during recent years has relied heavily on the use of computational simulation. For seismic analysis in particular, computer simulation, typically utilizing linear approximations of structural behavior, has become standard practice. This report presents the results of a comprehensive study of the significance of model sophistication (i.e. linear vs. nonlinear) and pertinent modeling assumptions on the dynamic response of concrete arch bridges. The study uses the Bixby Creek Bridge, located in California, as a case study. In addition to presenting general recommendations for analysis of this class of structures, this report provides an independent evaluation of the proposed seismic retrofit for the Bixby Creek Bridge. Results from the study clearly illustrate a reduction of displacement drifts and redistribution of member forces brought on by the inclusion of material nonlinearity. The analyses demonstrate that accurate modeling of expansion joints, for the Bixby Creek Bridge in particular, is critical to achieve representative modal and transient behavior. The inclusion of near-field displacement pulses in ground motion records was shown to significantly increase demand on the relatively softer, longer period Bixby Creek Bridge arch. Stiffer, shorter period arches, however, are more likely susceptible to variable support motions arising from the canyon topography typical for this class of bridges.

  18. Effect of dental arch convexity and type of archwire on frictional forces

    NARCIS (Netherlands)

    Fourie, Zacharias; Ozcan, Mutlu; Sandham, John

    2009-01-01

    Introduction: Friction measurements in orthodontics are often derived from models by using brackets placed on flat models with various straight wires. Dental arches are convex in some areas. The objectives of this study were to compare the frictional forces generated in conventional flat and convex

  19. Level-ARCH Short Rate Models with Regime Switching

    DEFF Research Database (Denmark)

    Christiansen, Charlotte

    This paper introduces regime switching volatility into level- ARCH models for the short rates of the US, the UK, and Germany. Once regime switching and level effects are included there are no gains from including ARCH effects. It is of secondary importance exactly how the regime switching...

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

    Science.gov (United States)

    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.

  1. Double aortic arch and nasogastric tubes: A fatal combination

    Institute of Scientific and Technical Information of China (English)

    Julia Massaad; Kelly Crawford

    2008-01-01

    Double aortic arch is a common form of complete vascular ring that encircles both the trachea and the esophagus, and presents with various respiratory and esophageal symptoms, usually in the pediatric population.We present a case of double aortic arch in an adult patient that manifested as massive upper gastrointestinal bleeding after prolonged nasogastric intubation.

  2. Swallowing threshold parameters of subjects with shortened dental arches.

    NARCIS (Netherlands)

    Kreulen, C.M.; Witter, D.J.; Tekamp, F.A.; Slagter, A.P.; Creugers, N.H.J.

    2012-01-01

    OBJECTIVES: To quantify swallowing threshold parameters of subjects with a moderate shortened dental arch dentition (SDA: missing molar teeth, but premolar teeth in occluding position and uninterrupted anterior regions) compared to subjects with a complete dental arch dentition (CDA). METHODS: Fourt

  3. Modelling subset multivariate ARCH model via the AIC principle

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In this paper we consider the problem of identifying a parsimonious subset multivariate ARCH model based on the AIC principle. The proposed approach can reduce the number of parameters in the final ARCH specification and allows for non-constant correlations between the components. Some simulation results illustrate the viability of the proposed procedure.

  4. Aortic arch vessel anomalies associated with persistent trigeminal artery.

    Science.gov (United States)

    Lotfi, Mehrzad; Nabavizadeh, Seyed Ali; Foroughi, Amin Abolhasani

    2012-01-01

    Developmental anomalies of the aortic arch vessels and persistent trigeminal artery that is the most common of the four anomalous carotid-basilar anastomoses are repeatedly reported in the literature as separate entities. Herein we report a previously undescribed variant including the coexistence of persistent trigeminal artery, truncus bicaroticus and direct origin of left vertebral artery from aortic arch. PMID:22542381

  5. Evaluation of the Occlusion and Arch Dimensions in the Primary Dentition of an Iranian Population

    Directory of Open Access Journals (Sweden)

    Maryam Talebi

    2013-12-01

    Full Text Available Introduction: The objective of this study was to gather information about normal occlusion and arch dimensions in the primary teeth of the children belonging to an Iranian population. Methods: This descriptive cross-sectional study was performed on 68 children from the city of Mashhad in the 3-5 age range. Dental arch dimensions, interrelationships of primary canine and second molars, overbite and overjet were evaluated. Results: Primate space was observed on both sides of the arch in 82.2% of the subjects. The most prevalent type of primary molar relationship was flush terminal plane (52.1% followed by distal step (31.3% and then mesial step (16.7%. The primary canine relationship was ranked in the descending order of prevalence as Class I (77.1%, Class II (13.5%, end-to-end (5.2% and Class III (4.2%. Normal overbite and normal overjet was observed in 50% and 81.3% of cases, respectively. Conclusion: This study provides an insight into the dental arch dimensions, occlusion, spacing and crowding in primary dentition in Iranian children. In most of the cases, primate space and flush terminal plane were observed.

  6. Evaluation of the Occlusion and Arch Dimensions in the Primary Dentition of an Iranian Population

    Directory of Open Access Journals (Sweden)

    Maryam Talebi

    2013-01-01

    Full Text Available Introduction: The objective of this study was to gather information about normal occlusion and arch dimensions in the primary teeth of the children belonging to an Iranian population. Methods: This descriptive cross-sectional study was performed on 68 children from the city of Mashhad in the 3-5 age range. Dental arch dimensions, interrelationships of primary canine and second molars, overbite and overjet were evaluated. Results: Primate space was observed on both sides of the arch in 82.2% of the subjects. The most prevalent type of primary molar relationship was flush terminal plane (52.1% followed by distal step (31.3% and then mesial step (16.7%. The primary canine relationship was ranked in the descending order of prevalence as Class I (77.1%, Class II (13.5%, end-to-end (5.2% and Class III (4.2%. Normal overbite and normal overjet was observed in 50% and 81.3% of cases, respectively. Conclusion: This study provides an insight into the dental arch dimensions, occlusion, spacing and crowding in primary dentition in Iranian children. In most of the cases, primate space and flush terminal plane were observed.

  7. Multimodal optical measurement in vitro of surface deformations and wall thickness of the pressurized aortic arch.

    Science.gov (United States)

    Genovese, Katia; Humphrey, Jay D

    2015-04-01

    Computational modeling of arterial mechanics continues to progress, even to the point of allowing the study of complex regions such as the aortic arch. Nevertheless, most prior studies assign homogeneous and isotropic material properties and constant wall thickness even when implementing patient-specific luminal geometries obtained from medical imaging. These assumptions are not due to computational limitations, but rather to the lack of spatially dense sets of experimental data that describe regional variations in mechanical properties and wall thickness in such complex arterial regions. In this work, we addressed technical challenges associated with in vitro measurement of overall geometry, full-field surface deformations, and regional wall thickness of the porcine aortic arch in its native anatomical configuration. Specifically, we combined two digital image correlation-based approaches, standard and panoramic, to track surface geometry and finite deformations during pressurization, with a 360-deg fringe projection system to contour the outer and inner geometry. The latter provided, for the first time, information on heterogeneous distributions of wall thickness of the arch and associated branches in the unloaded state. Results showed that mechanical responses vary significantly with orientation and location (e.g., less extensible in the circumferential direction and with increasing distance from the heart) and that the arch exhibits a nearly linear increase in pressure-induced strain up to 40%, consistent with other findings on proximal porcine aortas. Thickness measurements revealed strong regional differences, thus emphasizing the need to include nonuniform thicknesses in theoretical and computational studies of complex arterial geometries.

  8. Seismic multi-arch structures in East China

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    In previous papers (Wencai, 2002, 2003), the author has analyzed the deep seismic reflection profiles along some of the Mesozoic plutons in East China, and has pointed out that the crustal structures around these intrusions usually correlate with a special seismic fabric called the seismic multi-arch structure. This paper will continue to show main characteristics of the seismic multi-arch structures and discuss their relationship with mantle-origin magmatism and the lithospheric thinning process. Calibration of seismic reflectors in Chinese continental drilling sites shows that small-scale arch-like reflectors can be generated by fractured eclogites or other plutons, they do not belong to the multi-arch structure specially discussed in the paper. The multi-arch structure is characterized by several arch-like reflectors distributed in both the upper and lower crust with granitoid plutons or stocks exposed on the surface, which do not have obvious negative Europium anomalies. Based on the distribution pattern of arch reflectors, the multi-arch magmatic structures can be divided into three main types, namely the simple vertical combination type, the spread arch magmatic structure and the arch-bouquet structure. All of them correlate to mantle-origin magmatism, but occur in different places. The spread arch magmatic structures occur within a Mesozoic/Cenozoic rift zone with very thin and hot lithosphere. The vertical combination type of the multi-arch structures occurred near the rift zones where lithosphere was thin and hot. The arch-bouquet magmatic structures occur far from the rift zones where the lithosphere is not hot. The continental rifting acted as the late episode of the lithospheric thinning process seeing that the rift zones usually coincide with the thinnest parts of the lithosphere in East China. In different locations within the lithospheric thinning areas, mantle-origin magmatic activities have different characteristics, which might generate different

  9. Study on Forest Products PPI Index Fluctuation in China Based on ARCH Family-HP Filter Model%中国林产品PPI指数波动的ARCH族-HP滤波分析

    Institute of Scientific and Technical Information of China (English)

    张宇青; 周应恒

    2013-01-01

    了解林产品生产者价格指数波动的特征对稳定林产品PPI和价格水平有重要意义。采用ARCH-LM和残差平方和相关图方法检验后认为:木材、竹材PPI序列不存在不存在ARCH效应;HP滤波分析显示木材和竹材行业的P P I指数长期趋势比较平稳,相比于木材市场,近期竹材的市场供求状态相对合理;采用GARCH-M、 TARCH和EARCH模型分析认为胶脂和果实类林产品市场不存在“高风险-高收益”特征,但胶脂和果实类林产品PPI指数波动存在非对称性。%It’s important to Learn characteristics of forest products producer price index volatility for stable PPI and the price level. After Using ARCH-LM and the residual sum of squares correlation di-agram method. We considerst that: wood, bamboo PPI does not exist ARCH effect, HP filter analy-sis shows wood and bamboo industry PPI index slong-term trend is relatively stable, compared to the timber market, supply and demand status of bamboo market relatively reasonable;using GARCH-M, TARCH and EARCH model analysis that plastic resin and fruit category forest products does not exist“high risk - high return” feature, but it’s PPI index fluctuations exist asymmetry.

  10. 改良咬合重建治疗严重交错咬合的临床研究%A clinical study of improved occlusal reconstructions to partial denture arches with seriously interlaced occlusion

    Institute of Scientific and Technical Information of China (English)

    胡胜; 陈茂冲; 黄瑞涛

    2010-01-01

    目的 探讨治疗严重交错咬合的上下牙列缺损病例有效实用并且价格较低廉的治疗方法.方法 对严重交错咬合患者进行固定与铸造颌垫式可摘局部义齿联合修复咬合重建,在治疗前后分别进行咀嚼效率的检测和颞颌关节功能检查.结果 治疗后,患者咀嚼功能显著提高,颞颌关节功能有了明显的改善.结论 固定与铸造颌垫式局部义齿联合修复咬合重建是治疗严重交错咬合患者有效的方法之一.%Objective To investigate the effective and inexpensive therapy to partial denture arches with seriously interlaced occlusion. Methods Occlusal reconstructions with fixed and removable prosthesis were taken to cure partial denture arches with seriously interlaced occlusion. Masticatory efficiency was measured and X-rays of Schillers position were taken before and after therapy. Results After therapy masticatory efficiency was raised. And the function of TMJ was better. Conclusion Occlusal reconstruction with fixed and removable prosthesis is an effective way to cure partial denture arches with seriously interlaced occlusion.

  11. Left testicular artery arching over the ipsilateral renal vein

    Institute of Scientific and Technical Information of China (English)

    Munekazu Naito; Hayato Terayama; Yoichi Nakamura; Shogo Hayashi; Takayoshi Miyaki; Masahiro Itoh

    2006-01-01

    Aim: To report two cases of the left testicular artery arching over the left renal vein (LRV) before running downward to the testis. Methods: The subjects were obtained from two Japanese cadavers. During the student course of gross-anatomical dissection, the anatomical relationship between the testicular vessels and the renal vein was specifically observed. Results: The arching left testicular artery arose from the aorta below the LRV and made a loop around the LRV, which appeared to be mildly compressed between the arching artery and the psoas major muscle.Conclusion: Clinically, compression of the LRV between the abdominal aorta and the superior mesenteric artery occasionally induces LRV hypertension, resulting in varicocele, orthostatic protenuria and hematuria. Considering that the incidence of a left arching testicular artery is higher than that of a right one, an arching left artery could be an additional cause of LRV hypertension.

  12. Seismic behavior of concrete filled steel tubular arch structures

    Institute of Scientific and Technical Information of China (English)

    Xiong Feng; Sashi K Kunnath; Liu Haowu

    2005-01-01

    Shaking table tests of a 1:10 scale arch model performed to investigate the seismic behavior and resistance of concrete filled steel tubular (CFT) arch structures are described in this paper. The El-Centro record and Shanghai artificial wave were adopted as the input excitation. The entire test process can be divided into three stages depending on the lateral brace configurations, i.e., fully (five) braced, two braces removed, and all braces removed. A total of 46 tests, starting from the elastic state to failure condition, have been conducted. The natural vibration frequencies, responses of acceleration,displacement and strain were measured. From the test results, it is demonstrated that the CFT arch structures are capable of resisting severe ground motions and that CFT arches offer a credible alternative to reinforced concrete arches, especially in regions of high seismic intensity.

  13. Case study of risk assessment of and control over the double-arch tunnel construction in Beijing metro project%北京地铁双连拱隧道施工风险评价与控制实例研究

    Institute of Scientific and Technical Information of China (English)

    刘波; 张洪杰; 刘念; 王妙然

    2012-01-01

    以北京某地铁工程为背景,将层次分析法应用到双连拱区间隧道施工安全风险评价中.在风险评价过程中,结合双连拱隧道施工特点,识别双连拱隧道施工过程中所存在的风险,运用层次分析法进行风险评估,得出影响双连拱区间隧道施工安全的风险因素权重排序,运用Expert Choice软件对施工过程风险因素进行灵敏性分析.结果表明,在双连拱区间隧道施工过程中,施工人员技术水平不高、安全风险意识淡薄风险最大.根据安全风险评价结果,进行了施工风险控制研究,采取相应的风险控制措施,达到减小风险发生概率和最大程度降低损失的目的.%This paper is inclined to introduce the results of a case study of risk assessment of and control over the double-arch tunnel construction in Beijing Metro Project, in which we have applied the Analytic Hierarchical Processing (AHP) method to the risk assessment in the double-arch interval tunnel construction safety. In our assessment process, we have divided the double-arch tunnel construction safety risk factors into three categories, that is, the environmental risk factors, construction risk factors and the management risk factors based on the analysis of the construction features. Once the three kinds of factors were displayed before us, it would be possible to establish a hierarchical structure for double-arch tunnel construction safety at 4 levels. And, then, we have built up a pair-to-pair comparison matrix, a weighted sequence of risk factors to be included which affect the complicated double-arch tunnel construction. Afterwards, we have adopted a software named 'Expert choice' to the sensitivity analysis of the above-said risk factors in the construction process. Through such sensitivity analysis, we have gained different weighted sequences with one or more risk factors being various. The results of the weight sequencing and sensitivity analysis indicate that the root

  14. A quantitative approach for measuring crowding in the dental arch: Fourier descriptors.

    Science.gov (United States)

    Lestrel, Pete E; Takahashi, Osamu; Kanazawa, Eisaku

    2004-06-01

    Dental crowding is defined as a discrepancy between tooth size and jaw size that results in a misalignment of the tooth row. Proposed reasons for crowding include excessively large teeth, small jaws, and a combination of both. Nevertheless, the parameters that would allow the prediction of crowding have not been identified. This study compared the shape of crowded and uncrowded dental arches, matched for size and sex. The application of elliptical Fourier functions (EFFs) provided an accurate numeric description of the dental arch form. Dental casts from the Nihon University School of Dentistry at Matsudo, Chiba, Japan, were studied. Group I, the control group, consisted of 118 dental cast pairs (49 female, 69 male, aged 20.40 +/- 1.68 years [mean +/- SD]) with little or no crowding. Group II, which exhibited crowding, consisted of 78 dental cast pairs (64 female, 14 male, aged 19.67 +/- 4.95 years). From photographs, a set of 24 homologous points describing the tooth row was identified. These points were then fitted with EFFs. Each maxillary and mandibular outline was subsequently standardized for size by scaling the bounded area to a constant 10,000 mm(2). These "shape only" data were used to assess differences between arches in the 2 groups. By multivariate analysis of variance, statistically significant shape differences between groups I and II were obtained for both arches. Patients with crowding exhibited more variability than did the controls. This variability was illustrated with canonical axes derived from discriminant function analysis. PMID:15179396

  15. Mission archéologique islamique

    Directory of Open Access Journals (Sweden)

    Claire Hardy-Guilbert

    1997-11-01

    Full Text Available La troisième mission exploratoire du programme de recherches archéologiques sur la période islamique au Yémen s'est déroulée du 1 au 22 décembre 1995, en collaboration avec le Dr Ahmad Bataya, et a porté sur la côte méridionale, entre Abyan et Sayhut. Outre une étude approfondie de la ville d'al-Shihr, les prospections ont porté sur les régions d'Abyan, Ahwar et Sayhut. Prospection de la côte : Si Aden-même, le plus grand port yéménite depuis le 10ème siècle, est aujourd'hui trop urba...

  16. Optimization design of foundation excavation for Xiluodu super-high arch dam in China

    Directory of Open Access Journals (Sweden)

    Qixiang Fan

    2015-04-01

    Full Text Available With better understanding of the quality and physico-mechanical properties of rocks of dam foundation, and the physico-mechanical properties and structure design of arch dam in association with the foundation excavation of Xiluodu arch dam, the excavation optimization design was proposed for the foundation surface on the basis of feasibility study. Common analysis and numerical analysis results demonstrated the feasibility of using the weakly weathered rocks III1 and III2 as the foundation surface of super-high arch dam. In view of changes in the geological conditions at the dam foundation along the riverbed direction, the design of extending foundation surface excavation area and using consolidating grouting and optimizing structure of dam bottom was introduced, allowing for harmonization of the arch dam and foundation. Three-dimensional (3D geomechanics model test and finite element analysis results indicated that the dam body and foundation have good overload stability and high bearing capacity. The monitoring data showed that the behaviors of dam and foundation correspond with the designed patterns in the construction period and the initial operation period.

  17. The Diversity of High- and Intermediate-Velocity Clouds Complex C versus IV Arch

    CERN Document Server

    Richter, P; Wakker, B P; Savage, B D; Tripp, T M; Murphy, E M; Kalberla, P M W; Jenkins, E B

    2001-01-01

    We present Far Ultraviolet Spectroscopic Explorer (FUSE) and Space Telescope Imaging Spectrograph (STIS) observations of interstellar ultraviolet absorption lines in the Galactic high-velocity cloud Complex C and the Intermediate Velocity Arch (IV Arch) in direction of the quasar PG 1259+593 (l=120,b=+58 deg). Absorption lines from CII, NI, NII, OI, AlII, SiII, PII, SII, ArI, FeII, and FeIII are used to study the atomic abundances in these two halo clouds at V_LSR=-130 km/s (Complex C) and V_LSR=-55 km/s (IV Arch). The OI/HI ratio provides the best measure of the overall metallicity in the diffuse interstellar medium, because ionization effects do not alter the ratio, and oxygen is at most only lightly depleted from the gas into dust grains. For Complex C, we find an oxygen abundance of 0.093 (+0.125, -0.047) solar, consistent with the idea that Complex C represents the infall of low metallicity gas onto the Milky Way. In contrast, the oxygen abundance in the IV Arch is 0.98 (+1.21,-0.46) solar, which indicat...

  18. Changes in lower dental arch dimensions and tooth alignment in young adults without orthodontic treatment

    Directory of Open Access Journals (Sweden)

    Bruno Aldo Mauad

    2015-06-01

    Full Text Available OBJECTIVE: The aim of this longitudinal study, comprising young adults without orthodontic treatment, was to assess spontaneous changes in lower dental arch alignment and dimensions. METHODS: Twenty pairs of dental casts of the lower arch, obtained at different time intervals, were compared. Dental casts obtained at T1 (mean age = 20.25 and T2 (mean age = 31.2 were compared by means of paired t-test (p 0.05. Furthermore, incisors irregularity at T2 could not be predicted due to the severity of this variable at T1 (p = 0.5051. CONCLUSION: Findings suggest that post-growth maturation of the lower dental arch leads to a reduction of dental arch dimensions as well as to a mild, yet significant, increase in dental crowding, even in individuals without orthodontic treatment. Furthermore, dental alignment in the third decade of life cannot be predicted based on the severity of dental crowding at the end of the second decade of life.

  19. Optimization design of foundation excavation for Xiluodu super-high arch dam in China

    Institute of Scientific and Technical Information of China (English)

    Qixiang Fan; Shaowu Zhou; Ning Yang

    2015-01-01

    With better understanding of the quality and physico-mechanical properties of rocks of dam foundation, and the physico-mechanical properties and structure design of arch dam in association with the foun-dation excavation of Xiluodu arch dam, the excavation optimization design was proposed for the foundation surface on the basis of feasibility study. Common analysis and numerical analysis results demonstrated the feasibility of using the weakly weathered rocks III1 and III2 as the foundation surface of super-high arch dam. In view of changes in the geological conditions at the dam foundation along the riverbed direction, the design of extending foundation surface excavation area and using consolidating grouting and optimizing structure of dam bottom was introduced, allowing for harmonization of the arch dam and foundation. Three-dimensional (3D) geomechanics model test and finite element analysis re-sults indicated that the dam body and foundation have good overload stability and high bearing capacity. The monitoring data showed that the behaviors of dam and foundation correspond with the designed patterns in the construction period and the initial operation period.

  20. Earthquake analysis of arch and gravity dams including the effects of foundation inhomogeneity

    Institute of Scientific and Technical Information of China (English)

    LIN Gao; DU Jianguo; HU Zhiqiang

    2007-01-01

    Dam-foundation interaction plays an important role in the design of earthquake-resistant concrete arch and gravity dams.Geological conditions of the dam canyon are usually very complicated;however,in the literature,the damfoundation interaction analysis is often carried out based on the premise of a homogeneous unbounded foundation.In this paper,the effect of foundation inhomogeneity on the seismic response of arch and gravity dams was studied by means of scaled boundary finite element method (SBFEM).In order to satisfy the similarity requirement of SBFEM and simplify the computational effort,a subdomain approach and a conical representation of an unbounded foundation were proposed.The way of partitioning the domain and the selection of open angle and bottom radius of the cone model on the accuracy of the result were examined.Numerical examples show that the proposed approach is rational and efficient.Cases of foundation inhomogeneity with stiffness varying in accordance with an exponential function along the radial direction,and cases of foundation inhomogeneity with stiffness discontinuity and with weak interlayer strata on the earthquake response of concrete arch dams as well as gravity dams were analyzed.It was found that a homogeneous idealization of the unbounded foundation may sometimes greatly underestimate the maximum earthquake stress response of the dam.Therefore,taking into account the effect of foundation inhomogeneity for the earthquake safety assessment of concrete arch and gravity dams has great significance.

  1. Parallel computation of seismic analysis of high arch dam

    Institute of Scientific and Technical Information of China (English)

    Chen Houqun; Ma Huaifa; Tu Jin; Cheng Guangqing; Tang Juzhen

    2008-01-01

    Parallel computation programs are developed for three-dimensional meso-mechanics analysis of fully-graded dam concrete and seismic response analysis of high arch dams (ADs), based on the Parallel Finite Element Program Generator (PFEPG). The computational algorithms of the numerical simulation of the meso-structure of concrete specimens were studied. Taking into account damage evolution, static preload, strain rate effect, and the heterogeneity of the meso-structure of dam concrete, the fracture processes of damage evolution and configuration of the cracks can be directly simulated. In the seismic response analysis of ADs, all the following factors are involved, such as the nonlinear contact due to the opening and slipping of the contraction joints, energy dispersion of the far-field foundation, dynamic interactions of the dam-foundation-reservoir system, and the combining effects of seismic action with all static loads. The correctness, reliability and efficiency of the two parallel computational programs are verified with practical illustrations.

  2. Total aortic arch replacement: superior ventriculo-arterial coupling with decellularized allografts compared with conventional prostheses.

    Directory of Open Access Journals (Sweden)

    Alexander Weymann

    Full Text Available To date, no experimental or clinical study provides detailed analysis of vascular impedance changes after total aortic arch replacement. This study investigated ventriculoarterial coupling and vascular impedance after replacement of the aortic arch with conventional prostheses vs. decellularized allografts.After preparing decellularized aortic arch allografts, their mechanical, histological and biochemical properties were evaluated and compared to native aortic arches and conventional prostheses in vitro. In open-chest dogs, total aortic arch replacement was performed with conventional prostheses and compared to decellularized allografts (n = 5/group. Aortic flow and pressure were recorded continuously, left ventricular pressure-volume relations were measured by using a pressure-conductance catheter. From the hemodynamic variables end-systolic elastance (Ees, arterial elastance (Ea and ventriculoarterial coupling were calculated. Characteristic impedance (Z was assessed by Fourier analysis.While Ees did not differ between the groups and over time (4.1±1.19 vs. 4.58±1.39 mmHg/mL and 3.21±0.97 vs. 3.96±1.16 mmHg/mL, Ea showed a higher increase in the prosthesis group (4.01±0.67 vs. 6.18±0.20 mmHg/mL, P<0.05 in comparison to decellularized allografts (5.03±0.35 vs. 5.99±1.09 mmHg/mL. This led to impaired ventriculoarterial coupling in the prosthesis group, while it remained unchanged in the allograft group (62.5±50.9 vs. 3.9±23.4%. Z showed a strong increasing tendency in the prosthesis group and it was markedly higher after replacement when compared to decellularized allografts (44.6±8.3 dyn·sec·cm(-5 vs. 32.4±2.0 dyn·sec·cm(-5, P<0.05.Total aortic arch replacement leads to contractility-afterload mismatch by means of increased impedance and invert ventriculoarterial coupling ratio after implantation of conventional prostheses. Implantation of decellularized allografts preserves vascular impedance thereby improving

  3. Including Functional Annotations and Extending the Collection of Structural Classifications of Protein Loops (ArchDB

    Directory of Open Access Journals (Sweden)

    Antoni Hermoso

    2007-01-01

    Full Text Available Loops represent an important part of protein structures. The study of loop is critical for two main reasons: First, loops are often involved in protein function, stability and folding. Second, despite improvements in experimental and computational structure prediction methods, modeling the conformation of loops remains problematic. Here, we present a structural classification of loops, ArchDB, a mine of information with application in both mentioned fields: loop structure prediction and function prediction. ArchDB (http://sbi.imim.es/archdb is a database of classified protein loop motifs. The current database provides four different classification sets tailored for different purposes. ArchDB-40, a loop classification derived from SCOP40, well suited for modeling common loop motifs. Since features relevant to loop structure or function can be more easily determined on well-populated clusters, we have developed ArchDB-95, a loop classification derived from SCOP95. This new classification set shows a ∼40% increase in the number of subclasses, and a large 7-fold increase in the number of putative structure/function-related subclasses. We also present ArchDB-EC, a classification of loop motifs from enzymes, and ArchDB-KI, a manually annotated classification of loop motifs from kinases. Information about ligand contacts and PDB sites has been included in all classification sets. Improvements in our classification scheme are described, as well as several new database features, such as the ability to query by conserved annotations, sequence similarity, or uploading 3D coordinates of a protein. The lengths of classified loops range between 0 and 36 residues long. ArchDB offers an exhaustive sampling of loop structures. Functional information about loops and links with related biological databases are also provided. All this information and the possibility to browse/query the database through a web-server outline an useful tool with application in the

  4. 圬工拱桥重要性系数分布与倒塌模式相关性研究%Study on correlation between importance coefficient distribution and collapse mode of masonry arch bridge

    Institute of Scientific and Technical Information of China (English)

    彭卫兵; 史贤豪; 刘萌成; 谢波

    2013-01-01

    系统研究基于广义刚度法的构件重要性评价理论在桥梁结构倒塌过程分析中的应用,具体包括以下内容:①推导基于实体单元高斯点应力计算的单元重要性系数计算公式;②用C#和VS.net 2005编程实现单元重要性系数的计算和显示程序的开发;③采用上述程序研究悬臂梁重要性系数的分布以及在重要性系数最大的单元旁进行加固后结构重要性系数的变化;④进一步研究双跨圬工拱桥在试验荷载作用下的重要性系数分布与倒塌模式的关系,并与试验结构进行对比验证.研究结果表明:①在重要性系数最大的单元处进行加固将有效降低最大结构重要性系数,并能使单元重要性系数分布均匀;②结构重要性系数分布局部峰值对应着破坏时可能出现塑性铰的最大个数,且塑性铰出现的顺序由重要性系数局部峰值高的位置向重要性系数局部峰值低的位置传递;③线弹性计算结构重要性系数局部峰值分布位置与考虑结构材料非线性计算结果一致,但方差更大.%The application of the component importance evaluation theory in collapsing process analysis of bridge is studied based on the Generalized Rigidity Method.The research includes the following aspects:① the calculation formula of unit importance coefficient is deduced on the basis of Gauss point stress calculation in solid element,② the calculation of unit importance coefficient and the display program are realized using C # and VS.net 2005,③ the importance coefficient distribution of cantilever beam structure and the changes of importance coefficient after reinforcement in the side of the maximum unit are also discussed,④ the further research will focus on the correlation between importance coefficient distribution and collapse mode of two-span masonry arch bridge under the test load.The results indicate that the reinforcement on the element with maximum coefficient

  5. Multilineage differentiation of ectomesenchymal cells isolated from the first branchial arch.

    Science.gov (United States)

    Deng, M J; Jin, Y; Shi, J N; Lu, H B; Liu, Y; He, D W; Nie, X; Smith, A J

    2004-01-01

    Cranial neural crest-derived ectomesenchymal cells may be pluripotent stem cells that are capable of generating a range of phenotypes. The fate of these cells appears to be determined in part by intrinsic genetic programs and also by the influence of extracellular signals in the local environment. The extent of lineage determination once neural crest cells have migrated to the first branchial arch is not clear, although branchial arch pattern is not thought to be the result of crest predetermination. The aim of the present study was to test the hypothesis that ectomesenchymal cells of the first branchial arch show properties of pluripotent stem cells, the lineage of which may be directed by specific molecular signaling. Ectomesenchymal cells were enzymatically isolated from the mandibular processes of BALB/c mice and maintained in an undifferentiated state while cultured with leukemia inhibitory factor or induced to differentiate by lineage-specific induction factors or growth conditions, including transforming growth factor beta, forskolin, and a mineralization-promoting medium. Morphological observations and immunocytochemistry demonstrated that cells could be induced to differentiate into smooth muscle cells, glial cells, and osteoblasts, respectively. In the presence of the mineralization-promoting medium, alkaline phosphatase activity increased significantly and mineralization nodules formed. The data reported support the concept that many, although not all, first branchial arch-derived ectomesenchymal cells show properties of multipotent stem cells, the subsequent fate of which can be influenced by induction factors and growth conditions. Some cells, however, showed a degree of commitment with respect to their fate. The possible application of first branchial arch-derived stem cells to tissue engineering of the orofacial tissues should involve consideration of the developmental stage of cell harvesting and the desired cell fate.

  6. Longitudinal force in continuously welded rail on long-span tied arch continuous bridge carrying multiple tracks

    Institute of Scientific and Technical Information of China (English)

    YAN Bin; DAI Gong-lian; GUO Wen-hua; XU Qing-yuan

    2015-01-01

    Considering arch rib, lateral brace, suspender, girder, pier and track position, the model for the interaction between long-span tied arch continuous bridge and multiple tracks was established by using steel-concrete composite section beam element to simulate concrete-filled steel tube (CFST) arch rib, using the beam element with rigid arm to simulate the prestressed concrete girder and using nonlinear bar element to simulate longitudinal constraint between track and bridge. Taking a (77+3×156.8+77) m tied arch continuous bridge with four tracks on the Harbin-Qiqihar Passenger Dedicated Line as an example, the arrangement of continuously welded rail (CWR) was explored. The longitudinal force in CWR on the tied arch continuous bridge, the pier top horizontal force and torque due to the unbalance load case, were analyzed under the action of temperature, vertical live load, train braking and wind load. Studies show that, it can significantly reduce track displacement to set the track expansion devices at main span arch springing on both sides; the track stress due to arch temperature variation can reach 40.8 MPa; the track stress, pier top horizontal force and torque are related to the number of loaded tracks and train running direction, and the bending force applied to unloaded track is close to the loaded track, while the braking force applied to unloaded track is 1/4 to 1/2 of the loaded track; the longitudinal force of track due to the wind load is up to 12.4 MPa, which should be considered.

  7. 双拱大跨屋盖结构风载的数值模拟研究%STUDY ON THE NUMERICAL SIMULATION OF WIND LOADS ACTING ON LARGE SPAN DOUBLE-ARCHED ROOF STRUCTURE

    Institute of Scientific and Technical Information of China (English)

    李晓润; 吴昌栋; 李悦; 陈水荣

    2011-01-01

    双拱大跨度网架屋盖结构由于体表为复杂曲面,其风荷载的确定不能仅参考我国建筑结构荷载规范中对风荷载的相关规定,风荷载的确定需要借助于其他手段。CFD数值模拟风洞是近年来发展起来的一种风荷载研究手段,基于ANSYS-CFX 12流体动力学软件,利用雷诺应力(RSM)湍流模型对一双拱大跨度屋盖结构上平均风载体型系数进行数值模拟研究,得到双拱大跨屋盖结构表面体型系数的极限值。建议结构设计人员在对结构表面风荷载进行计算时,可以按照该极限值对重点部位予以加强。%Due to the complexity of large span double-arched roof structure,Chinese load codes are not enough for the design.Other method should be used to ascertain the wind load on the roof structure.The distribution of wind pressure and wind environment on the roofs of large span double-arched structure were computed based on ANSYS-CFX12 software platform with Reynolds stress model(RSM).By the simulation,the unfavorable wind shape coefficient is obtained,which help the designer to enhance the key component for the safety of the serviceability performance when computing the wind load on the surface of a structure.

  8. Study on integral seismic safety of Dagangshan Arch dam-foundation system%大岗山拱坝-地基体系整体抗震安全性研究

    Institute of Scientific and Technical Information of China (English)

    涂劲; 李德玉; 陈厚群; 欧阳金惠

    2011-01-01

    Based on the integral seismic safety concept of clam-foundation system for arch dam, a corre-sponding analytical technique using FEM was developed. In this paper, the seismic safety of Dagangshan Arch Dam subjected to a design peak ground acceleration of 0.5S7 5g resulted in seismic overloading and shear strength reduction of the slide surfaces in the wedges are investigated respectively. In the numerical model, dam-reservoir-foundation interaction and nonlinear contact between contraction joints, dam-founda-tion interface as well as slide surfaces in abutment wedges are taken into account. Both dam body and criti-cal abutment wedge are treated as an integral system and the system safety are determined by one single safety criterion, defined as the point of inflection of the relationship curve between dam displacement and seismic overloading factor or shear strength reduction factor.%基于高拱坝-地基整体抗震安全评价体系,对设计地震动峰值加速度达0.556 5g的大岗山拱坝-地基体系的地震响应进行数值分析,并分别对其在不同地震超载倍数和不同基岩控制性滑裂面抗剪强度降低倍数下的安全性和破坏机理进行研究,以寻求坝体控制性位移或与位移相关的变量随安全系数变化曲线的拐点作为整体失稳判断准则,进一步明确了具体实施方法,并对其整体抗震安全性作出评价.

  9. Arch development with trans-force lingual appliances.

    Science.gov (United States)

    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. PMID:15794037

  10. Nonstationary ARCH and GARCH with t-distributed Innovations

    DEFF Research Database (Denmark)

    Pedersen, Rasmus Søndergaard; Rahbek, Anders

    Consistency and asymptotic normality are established for the maximum likelihood estimators in the nonstationary ARCH and GARCH models with general t-distributed innovations. The results hold for joint estimation of (G)ARCH effects and the degrees of freedom parameter parametrizing the t-distribut......Consistency and asymptotic normality are established for the maximum likelihood estimators in the nonstationary ARCH and GARCH models with general t-distributed innovations. The results hold for joint estimation of (G)ARCH effects and the degrees of freedom parameter parametrizing the t......-distribution. With T denoting sample size, classic square-root T-convergence is shown to hold with closed form expressions for the multivariate covariances....

  11. A comparison of four methods of predicting arch length.

    Science.gov (United States)

    Gardner, R B

    1979-04-01

    1. Four arch length prediction equations (Nance, Johnston-Tanaka, Moyers, and Hixon-Oldfather) were compared by examining pretreatment casts, pretreatment intraoral radiographs, and posttreatment casts of forty-one patients of mixed-dentition age. 2. A comparison of correlation coefficients and slopes of the predicted arch length versus the actual arch lengths revealed that the Hixon-Oldfather method conformed closest to the ideal. 3. No combination of the four methods produced a more accurate equation than the single most accurate method. 4. Neither the sex of the patient nor the type of occlusion affected the prediction accuracy of any of the four equations. 5. All methods tend to overpredict the arch length size by 1 to 3 mm., with the exception of the Hixon-Oldfather equation, which underpredicted by approximately 0.5 mm. 6. An analysis of the intrainvestigator error showed a very low standard error of estimate for individual tooth measurements and for the prediction values. 7. A variance analysis showed that most of the variation was due to arch length (85%), a slight amount was due to the prediction method (8%), and 6% of the variation was due to the rater. 8. A low correlation was found between space available versus actual discrepancy and space available versus actual arch length. 9. High correlation coefficients were found for the predicted arch lengths when compared with the actual arch lengths. As expected, the correlation coefficients for the predicted widths of only the canines and premolars compared with the actual widths were not quite as high. PMID:285614

  12. 桩网支承路基结构中土拱效应及网垫受力的模型试验研究%Model Study on Arch Effect and Bedding Force of Geosynthetics Reinforced and Pile Supported Embankment

    Institute of Scientific and Technical Information of China (English)

    蔡德钩; 闫宏业; 叶阳升; 张千里; 何华武; 杨生哲

    2011-01-01

    基于相似理论,对桩网支承路基中心土拱效应进行8组模拟试验.测试桩顶轴力、桩土及路基不同高度处应力、格栅拉力和桩间土沉降随路基高度、外荷载变化特性,探讨格栅受力后变形.结果表明:加筋网垫上方竖向应力与以球形拱理论为基础的德国规范计算结果较为接近;加筋网垫下方桩间土承担竖向应力随路基高度、上覆荷载增加而增加;黏性土路基成拱效率略低于砂土路基;对于两层格栅组成的加筋网垫,下层格栅承担土拱效应竖向应力引起拉力大于上层格栅,位于桩帽之间并垂直于桩帽边格栅拉力大于平行于桩帽边格栅拉力;格栅初始松紧状态对土拱成拱效率有一定影响;格栅受力后平面变形形状近似呈悬索状.研究成果可为我国桩网支承路基结构加筋网垫相关规范提供参考.%On the basis of the theory of similarity, eight model experiments have been made to test the arch effect of the geosynthetics reinforced and pile supported embankment (GRPS). The axial force of pile cap, stresses at different heights of the subgrade, tensile force of geosynthetics and inter-pile soil settlement and its variations with different heights of the subgrade and under different external loads have been measured in the course of filling and after filling. Deformations of geosynthetics have been studied. The results show as follows: Vertical stresses above the reinforced bedding are similar to the calculation results of the spherical shape arch method; vertical stresses below the reinforced bedding increase with upward-changing of the subgrade height and the superimposed load; arch forming efficiency of the clay filling material is a little lower than that of sand; for the reinforced bedding consisting of two layers geosynthetics, the tensile forces produced by the arch effect of the lower layer is greater than the upper layer; the tensile forces of the geosynthetics

  13. Theoretical and Experimental Investigation of the Nonlinear Behavior of an Electrostatically Actuated In-Plane MEMS Arch

    KAUST Repository

    Ramini, Abdallah H.

    2016-05-02

    We present theoretical and experimental investigation of the nonlinear behavior of a clamped-clamped in-plane MEMS arch when excited by a DC electrostatic load superimposed to an AC harmonic load. Experimentally, a case study of in-plane silicon micromachined arch is examined and its mechanical behavior is measured using optical techniques. An algorithm is developed to extract the various parameters, such as the induced axial force and the initial rise, needed to model the behavior of the arch. A softening spring behavior is observed when the excitation is close to the first resonance frequency due to the quadratic nonlinearity coming from the arch geometry and the electrostatic force. Also, a hardening spring behavior is observed when the excitation is close to the third (second symmetric) resonance frequency due to the cubic nonlinearity coming from mid-plane stretching. Dynamic snap-through behavior is also reported for larger range of electric loads. Theoretically, a multi-mode Galerkin reduced order model is utilized to simulate the arch behavior. General agreement is reported among the theoretical and experimental data.

  14. Is there any association between facial type and mandibular dental arch form in subjects with normal occlusion?

    Directory of Open Access Journals (Sweden)

    Luiz Renato Paranhos

    2014-03-01

    The aim of this study was investigate the association between the mandibular arch morphology and the facial type of Brazilian Caucasians with natural normal occlusion. For this, we used a sample comprised of lateral radiographs and respective dental casts of 51 individuals (21 male and 30 female, presenting at least 4 of the 6 Andrews’ keys to normal occlusion without previous orthodontic treatment. Angle’s first molar relationship was considered indispensable for the sample. The facial type was defined by two cephalometric measurements (SN.SGn and SN.GoGn. After scanning the models (3D and radiographs, the images were evaluated by 12 orthodontists. A modified Kappa test evaluated the agreement between examiners to classify the morphology of the dental arch. The chi-square test was used to verify the association between the facial type (dolichofacial, mesofacial, or brachyfacial and the dental arch morphology (square, oval, or tapered, using significance level of 5%. Casual and systematic errors (p > 0.05 showed no significant results and the Kappa test showed significant agreement among examiners for the dental arch form (0.55 with a p < 0.001, considered as ‘moderate’. The chi-square test indicated no significant association. The null hypothesis was accepted, as the facial type was not associated with dental arch morphology in individuals with normal occlusion.

  15. CORRECTION OF ALVEOLAR ARCH MALALIGNMENT AFTER TOTAL CORRECTION IN UNILATERAL AND BILATERAL GR III CLEFTS

    OpenAIRE

    Mohana Rao; Mukunda Reddy; Srikanth; Rambabu; Parvathi

    2015-01-01

    AIMS AND OBJECTIVES: Aim of this study is to document and analyse the pre - operative and postoperative alveolar arch impressions . MATERIALS AND METHODS: 20 cases of both unilateral and bilateral GR III clefts selected for this study. These pati ents were operated at the age of not less than 9 months, preferably below the age of 18 months. Below the age of 9 months general condition of these children may not cope up the duration of general anes...

  16. Edentulism and shortened dental arch in Brazilian elderly from the National Survey of Oral Health 2003

    OpenAIRE

    Marco Túlio de Freitas Ribeiro; Marco Aurélio Camargo da Rosa; Rosa Maria Natal de Lima; Andréa Maria Duarte Vargas; João Paulo Amaral Haddad; Ferreira, Efigênia Ferreira e

    2011-01-01

    OBJECTIVE: To describe the distribution of edentulism and estimate the prevalence of functional dentition and shortened dental arch among elderly population. METHODS: A population-based epidemiological study was carried out with a sample of 5,349 respondents aged 65 to 74 years obtained from the 2002 and 2003 Brazilian Ministry of Health/Division of Oral Health survey database. The following variables were studied: gender; macroregion of residence; missing teeth; percentage that met the World...

  17. The artificial somato-autonomic reflex arch does not improve bowel function in subjects with spinal cord injury

    DEFF Research Database (Denmark)

    Rasmussen, Mikkel Mylius; Krogh, Klaus; Clemmensen, Dorte;

    2015-01-01

    Study design: Prospective cohort study. Objective: Although introduced for neurogenic bladder dysfunction, it has been suggested that the artificial somato-autonomic reflex arch alleviates neurogenic bowel dysfunction (NBD). We aimed at evaluating the effects of the reflex arch on NBD. Setting......: Denmark. Methods: Ten subjects with supraconal spinal cord injury (SCI) (nine males, median age 46 years) had an anastomosis created between the ventral part of the fifth lumbar or first sacral nerve root and the ventral part of the second sacral nerve root. Standardized assessment of segmental colorectal...... transit times with radiopaque markers, evaluation of scintigraphic assessed colorectal emptying upon defecation, scintigraphic assessment of colorectal transport during stimulation of the reflex arch, standard anorectal physiology tests and colorectal symptoms were performed at baseline and 18 months...

  18. Traveling wave effect on the seismic response of a steel arch bridge subjected to near fault ground motions

    Institute of Scientific and Technical Information of China (English)

    Xu Yan; George C Lee

    2007-01-01

    In the 1990s, several major earthquakes occurred throughout the world, with a common observation that near fault ground motion (NFGM) characteristics had a distinct impact on causing damage to civil engineering structures that could not be predicted by using far field ground motions. Since then, seismic responses of structures under NFGMs have been extensively examined, with most of the studies focusing on structures with relatively short fundamental periods, where the traveling wave effect does not need to be considered. However, for long span bridges, especially arch bridges, the traveling wave (only time delay considered) effect may be very distinct and is therefore important. In this paper, the results from a case study on the seismic response of a steel arch bridge under selected NFGMs is presented by considering the traveling wave effect with variable apparent velocities. The effects of fling step and long period pulses of NFGMs on the seismic responses of the arch bridge are also discussed.

  19. The crystal structure of Mtr4 reveals a novel arch domain required for rRNA processing

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, R.N.; Robinson, H.; Klauer, A. A.; Hintze, B. J.; van Hoof, A.; Johnson, S. J.

    2010-07-01

    The essential RNA helicase, Mtr4, performs a critical role in RNA processing and degradation as an activator of the nuclear exosome. The molecular basis for this vital function is not understood and detailed analysis is significantly limited by the lack of structural data. In this study, we present the crystal structure of Mtr4. The structure reveals a new arch-like domain that is specific to Mtr4 and Ski2 (the cytosolic homologue of Mtr4). In vivo and in vitro analyses demonstrate that the Mtr4 arch domain is required for proper 5.8S rRNA processing, and suggest that the arch functions independently of canonical helicase activity. In addition, extensive conservation along the face of the putative RNA exit site highlights a potential interface with the exosome. These studies provide a molecular framework for understanding fundamental aspects of helicase function in exosome activation, and more broadly define the molecular architecture of Ski2-like helicases.

  20. 大跨度梁拱组合桥的梁轨相互作用设计参数研究%Study of Design Parameters of Beam-Track Interaction of Long Span Hybrid Bridge of Beam and Arch

    Institute of Scientific and Technical Information of China (English)

    戴公连; 刘瑶

    2015-01-01

    为了解梁轨相互作用设计参数对大跨度梁拱组合桥无缝线路的影响,以兰渝线广元段某(82.9+172+82.9) m梁拱组合桥为例,采用ANSYS 软件建立了考虑拱肋—吊杆—主梁—桥墩—桩基—轨道梁轨系统一体化有限元模型,分析了拱肋与吊杆升温、纵向阻力模型、吊杆间距、桥墩高度、制动力率、风荷载等参数对钢轨纵向力的传递规律。结果表明:拱肋升温对钢轨应力的影响较大,计算钢轨伸缩力时,按梁体升温15℃考虑较为安全;梁拱组合桥的梁轨相互作用根据《铁路无缝线路设计规范》计算较为安全;钢轨制动力随固定墩高度的增加而增大,固定墩的墩顶水平力与其墩高基本呈线性递减关系;钢轨应力随吊杆间距的增大而增加;钢轨的最大制动拉、压应力和固定墩的墩顶水平力均与制动力率呈线性关系;风荷载作用下,钢轨应力可达5.8 M Pa以上,风速较大区域需考虑风荷载对钢轨的影响。%To understand the effect of the design parameters of beam‐track interaction on the continuously welded rail on long span hybrid bridge of beam and arch ,a hybrid bridge of beam and arch with span arrangement (82 .9 + 172 + 82 .9 ) m on the Guangyuan section of Lanzhou‐Chongqing Railway was taken as an example ,a finite element model considering the integration of the arch rib -hanger-main beam -pier-pile foundation -beam‐track system was established ,u‐sing the software ANSYS and the effect of the design parameters ,such as the temperature rise in the arch rib and hanger ,longitudinal resistance model ,hanger spacing ,pier height ,braking force ratio and wind load ,on the longitudinal force transmission laws of the steel rail were analyzed . T he results of the analysis show that the effect of the temperature rise in the arch rib on the steel rail stress is great and w hen the steel rail expansion force is calculated

  1. Gothic Arch Tracing Using for Judgment on Unilateral Chewing Edentulous Patients: A Preliminary Study%哥特式弓描记法判断无牙颌患者偏侧咀嚼的初步研究

    Institute of Scientific and Technical Information of China (English)

    师晓蕊; 徐军; 史作慧

    2012-01-01

    目的:探讨无牙颌患者偏侧咀嚼的临床判定方法,为今后进一步研究患者的义齿修复提供参考.方法:对30例无牙颌患者进行哥特式弓描记及叩齿点的测量,使用三维精密平移台测量哥特式弓描记图像顶点、边缘运动各终点及叩齿点坐标,建立坐标系,计算肌力闭合道终点(MCP)相对于正中关系位(CRP)水平方向上的偏移量d、不对称指数AI(角度)、AI(幅度)以及AI(偏离),所得数据利用SPSS13.0进行统计分析.结果:30例无牙颌患者中2例(6.67%)MCP与CRP为同一位置,8例(26.67%)MCP与CRP在水平方向上协调,20例(66.67%)MCP与CRP在水平方向上存在不协调,最小偏离量为0.340 mm,最大偏离量可达到2.640 mm.20例MCP与CRP不协调的无牙颌患者中,14例患者的d值方向至少与AI(角度)、AI(幅度)、AI(偏离)中的1个指标方向相一致.结论:哥特式弓描记法作为判断无牙颌患者有无偏侧咀嚼的方法,有一定可信度,但其具体判定指标还需进一步研究,必要时应结合患者病史、心理状态等因素综合分析.%Objective: To discuss the judgment methods of unilateral chewing among edentulous patients and provide reference for further research on denture restoration for these unilateral chewing patients. Methods; 30 edentulous patients were included and their Gothic arch tracing and tapping point results were analyzed, d value(the horizontal deviation between MCP and CRP) , AI (angle/range/deviation) were calculated and analyzed using SPSS 13. 0. Results: Among 30 edentulous patients, 2 (6. 67%) patients' MCP was the same as CRP, 8(26. 67% )patients' MCP was coordinated with CRP in the horizontal direction, 20(66. 67%) patients ' MCP was uncoordinated with CRP in the horizontal direction. Within these 20 patients, the minimum d value was 0. 340mm, maximum value was 2. 640mm, the direction of d value was the same as the direction of at least one of the three AI values in 14 unilateral

  2. 基于实测变形的高拱坝力学参数智能优选研究%A Study of Intelligent Optimized Mechanical Parameters of High Arch Dams Based on Measured Deformation

    Institute of Scientific and Technical Information of China (English)

    陈勋辉; 程中凯; 景继; 黄耀英; 万智勇

    2015-01-01

    As the complexity and uncertainty of arch dam body and bedrock ,it is very difficult to obtain calculated parameters accu‐rately .As a result ,the mechanical parameters of high arch dams based on measured deformation is back-analyzed in this paper . Firstly ,by combining the design parameters of comprehensive elastic modulus of dam body and bedrock through uniform design theo‐ries by using the finite element method to obtain the sample of the difference value of water pressure component separated from sever‐al typical points ,then the difference value of water pressure component under water pressure is taken as the import of neural net‐works ,the unknown inverse parameters are taken as outputs correspondingly ,the neural network was established .It was trained to describe the nonlinear relationship between inverse parameters and dam displacements of several typical points .Secondly ,the actual difference value of water pressure component separated from several typical points is input into the trained neural networks to obtain the real material parameters .As an example ,the elastic modulus of dam bodies and rock masses of dam foundations under the base of a high arch dam in southwest are back-analyzed by the above method .It indicates that the difference values of water pressure com‐ponent of several typical points under water pressure were almost the same as the actual difference values ,so it can be concluded that the inversion values are reasonable ,and this inversion method is feasible .%由于高拱坝坝体和基岩工作条件复杂,难以准确给定计算参数,因此,基于实测变形反演高拱坝和基岩力学参数。首先采用均匀设计原理对坝体和基岩综合弹性模量进行设计参数组合,通过有限元正分析得到多个典型测点处坝体的水压分量差值样本,以水压荷载作用下的水压分量差值作为神经网络的输入,对应的待反演参数的样本值作为输出,训练神经网

  3. 桩承式加筋路堤三维土拱效应试验研究%Experimental study of 3D soil arching in piled reinforced embankments

    Institute of Scientific and Technical Information of China (English)

    曹卫平; 胡伟伟

    2014-01-01

    桩承式加筋路堤受力性状比较复杂,土拱效应对路堤的承载变形性状具有重要影响。通过三维土拱效应模型试验,研究桩-土相对位移、路堤高度、桩帽净间距和水平加筋体拉伸强度等因素对桩土应力比及路堤沉降的影响。结果表明:土拱效应发挥程度与桩-土相对位移密切相关,存在一个临界桩-土相对位移使得桩土应力比达到最大值,该临界桩-土相对位移约为6~8 mm。路堤高度与桩帽净间距之比越大,桩土应力比越大,路堤顶面差异沉降越小;桩帽宽度与桩帽净间距之比越大,桩土应力比越大,路堤顶面差异沉降越小。设置水平加筋体能有效提高桩土应力比并减小路堤顶面沉降;路堤越低,水平加筋体对桩土应力比的提高作用及对路面沉降的减小作用越明显;水平加筋体拉伸强度越高,这种作用越明显。桩承式加筋路堤三维土拱效应等沉面高度与桩帽净间距之比约为3.5。%Soil arching has a notable influence on the behavior of piled reinforced embankment for its mechanically complex nature. A series of 3D model tests are conducted to explore the influence of the pile-soil relative displacement, embankment height, pile-cap spacing and horizontal reinforcement tension strength on the stress concentration ratio as well as the embankment settlement. The test results show that: soil arching is closely related to the pile-soil relative displacement and there exists a critical pile-soil relative displacement of approximate 6 to 8 mm which makes the stress concentration ratio reaching its maximum value. The bigger the ratio of embankment height is to the pile-cap clear spacing, the bigger the stress concentration ratio and the smaller the differential settlement on the surface of the embankment are;a bigger ratio of the cap width to the pile-cap clear spacing will result in a bigger stress concentration ratio and a smaller

  4. 拱盖法地铁车站施工沉降规律及控制对策研究%Study on Rules and Countermeasures for Ground Surface Settlement in Construction of Metro Stations by Arch-cover Method

    Institute of Scientific and Technical Information of China (English)

    王丹; 张海波; 王渭明; 秦志斌; 孙捷城

    2015-01-01

    Zhongshan Park Station of Line 3 of Qingdao Metro,which is located in heterogeneous ground,is constructed by arch-cover method.In the paper,the excavation of the left,central and right pilot tunnels of the upper section of the Metro station,as well as the construction of the arch-cover and the excavation of the lower section of the Metro station, are analyzed by means of numerical simulation and by comparing with the measured data,so as to summarize the rules of the transverse and longitudinal settlement of the ground surface induced by the pilot tunnel excavation.Conclusions drawn are as follows:the influence scope of the pilot tunnel excavation is 12 m ahead of the tunnel face,the transverse influence radius of the excavation the upper section is 1 .5 times of the staion diameter,and the excavation of the upper section and the conversion between the arch-cover and the flexible support are the main causes for the settlement.Fur-thermore ,key countermeasures and empirical ground surface settlement formula are proposed for similar Metro stations in the heterogeneous ground in Qingdao.%为得出适用于上软下硬特殊地质条件下青岛地铁安全开挖方法及地表沉降规律,总结出相应的控制对策,通过数值模拟结合现场实测数据,分别对上断面以左中右导洞均错开12 m平行施工、柔性支撑换作拱盖二次衬砌及下断面开挖3个阶段进行分析。总结出导洞开挖的先后顺序对地表横向、纵向沉降曲线影响的规律,得到了掌子面超前变形范围为12 m、上断面开挖横向影响半径为1.5倍洞径,及上断面开挖和拱盖与柔性支撑的换作是导致沉降的主要原因等结论;根据导致沉降的主要施工步序提出了关键加固对策,并得出了青岛特殊复合地层条件的支护方法和地表沉降经验公式。

  5. Elasto-Viscoplastic Block Element Method and its Application to Arch Dam Abutment Slopes

    Science.gov (United States)

    Chen, S.-H.; Shahrour, I.; Egger, P.; Wang, W.-M.

    2002-08-01

    This paper presents an elasto-viscoplastic block element method and its application to the deformation and stability study of arch dam abutment slopes. The paper is composed of two parts. The first part concerns the numerical methods used in the analysis, which includes the identification of the rock blocky system, the algorithm of unconfined seepage flow in discontinuity network taking the grout curtain and drainage curtain into account, and the elasto-viscoplastic block element method as well. In the second part a complicated arch dam abutment slope is studied, from which the seepage flow, the deformation, and the safety factor of the abutment slope are obtained. Based on the analysis suggestions about the seepage control and stabilization measures are made.

  6. The fundamental concepts of the limit design of stone arches; La verifica degli archi a conci lapidei

    Energy Technology Data Exchange (ETDEWEB)

    Clemente, Paolo [ENEA, Centro Ricerche Casaccia, Rome (Italy). Dipt. Ambiente

    1997-07-01

    Stone arches represent one of the most interesting topics in the field of the preservation of historic and monumental structures. The reason of this interest is related to the conservation of ancient structures, which have arrived until our age and to the relatively recent construction, especially railway bridges, of this century. In this paper the fundamental concepts of the limit design of stone arches are discussed. The simple case of funicular arch is first shown. Then the two classical shape are studied, parabolic and circular, subject to dead loads only. Finally, the effects of live loads and seismic loads are analyzed. The numerical analysis were carried out by means of computer codes. The results are plotted in diagrams to be used for the structural check.

  7. A Review of Diseases of Aortic Arch: Diagnosis by CTA

    Directory of Open Access Journals (Sweden)

    S. Sabouri

    2007-05-01

    Full Text Available The noninvasive revolution in cardiovascular imaging has altered the diagnostic algorithm for all types of acquired and congenital cardiovascular disease. CT techniques are commonly used in the diagnosis of aortic arch and its major branch vessels as well as thoracic and abdominal aortic diseases. CT angiogra-phy combines with CT scans obtained detailed in-formation on precise morphology and extent of dis-ease. Studies were performed on an MDCT unit (4row GE light speed. In infants and small children, the seda-tion rate for CT was lower than that used for patients of similar age undergoing cardiac MR imaging. Seda-tion times ranged between 5 and 10 min, in the pedi-atric population, MDCT was performed with a 1- to 2.5-mm slice thickness in adults, MDCT was per-formed with a 2.5-mm slice thickness with 50% re-construction overlap, pitch 0.75-1.CT angiographic studies were performed with nonionic contrast mate-rial with iodine concentrations of 300 mg/mL admin-istered at a dose of 2-3 mL/kg. Contrast material was injected by power injection, followed by normal sa-line, an automated bolus-tracking technique was used at an injection rate of 2-4 mL/sec. the bolus-tracking device was placed on the ascending aorta. For pa-tients with thoracic outlet syndrome, CT angiogram was performed with neutral position of arm and ab-duction of the arm. Radiologist studied the CT image data in an axial cine paging mode as well as multiplanar reformations. To plan effective management of Aorta disease, CTA is displayed using a combination of 3D images, such as those obtained by multiplanar reformation (MPR, curved planar reformation (CPR, maximum intensity projection (MIP and volume rendering (VR. Case reports include coarctation of aorta, vascular ring, right sided aorta, interrupted aortic arch, abber-ant vessels, paitent ductus arteriosus, subclavian steel syndrome, aneurysm, dissection, thoracic outlet syn-drome, arthritis and atherosclerotic stenosis.

  8. Evaluation of Dynamic Load Factors for a High-Speed Railway Truss Arch Bridge

    Directory of Open Access Journals (Sweden)

    Ding Youliang

    2016-01-01

    Full Text Available Studies on dynamic impact of high-speed trains on long-span bridges are important for the design and evaluation of high-speed railway bridges. The use of the dynamic load factor (DLF to account for the impact effect has been widely accepted in bridge engineering. Although the field monitoring studies are the most dependable way to study the actual DLF of the bridge, according to previous studies there are few field monitoring data on high-speed railway truss arch bridges. This paper presents an evaluation of DLF based on field monitoring and finite element simulation of Nanjing DaShengGuan Bridge, which is a high-speed railway truss arch bridge with the longest span throughout the world. The DLFs in different members of steel truss arch are measured using monitoring data and simulated using finite element model, respectively. The effects of lane position, number of train carriages, and speed of trains on DLF are further investigated. By using the accumulative probability function of the Generalized Extreme Value Distribution, the probability distribution model of DLF is proposed, based on which the standard value of DLF within 50-year return period is evaluated and compared with different bridge design codes.

  9. INCREASING EFFICIENCY OF A CONNECTION OF UNIFIED ELEMENTS OF AN ARCH OF LIGHTWEIGHT BUILDINGS

    Directory of Open Access Journals (Sweden)

    Fakhrutdinov A. E.

    2013-02-01

    Full Text Available Statement of the problem. When designing lightweight arch buildings using the principle of an “open” standardizing, which provides the erection of load-carrying arches of any outline from a set of unified elements, the major question to be addressed is the development of an effective connection of unified elements providing their connection at arbitrary angles. Results. Numerical studies were made of a connection of thin-walled cold-bent open-section profiles on self-drilling, based on which an optimum disposition of self-drilling screws providing the greatest durability and rigidity of connection was defined. The experimental studies were made of models of connections of unified elements with a proposed disposition of self-drilling screws. Also, numerical and experimental studies of a new way of strengthening thin-walled elements connection were provided. Conclusions. The data obtained in numerical and experimental studies allow us to draw conclu-sions about perspectivity and expediency of the proposed ways of increasing efficiency of unified elements connection of a lightweight arch building.

  10. The Role of Arch Compression and Metatarsophalangeal Joint Dynamics in Modulating Plantar Fascia Strain in Running

    OpenAIRE

    McDonald, Kirsty A.; Sarah M. Stearne; 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...

  11. A Flexible Network Structure for Temperature Monitoring of a Super High Arch Dam

    OpenAIRE

    Peng Lin; Qingbin Li; Hang Hu

    2012-01-01

    The aim of the study presented in this paper is to develop a flexible network structure for temperature monitoring of a super high arch dam under construction period. The multiple channel temperature acquisition method collects and analyzes system including flexible and stable field bus for the sensors, communication between intelligent module and control unit is proposed. In this temperature monitoring system, a total of 3 kinds of networks which independently marked by ∗(1), ∗(2), and ∗(3) ...

  12. Comparison of Retentive Force in Four Attachment Systems in Implant- Supported Overdenture of the Lower Arch

    OpenAIRE

    Ahmadzadeh A; Fereidoonpoor N.

    2012-01-01

    tement of Problem: Along with the rapid population growth in recent decades, there has been an increase in the number of edentulous patients who have complications with conventional denture. This entails the use of dentures, such as implant overdenture, which are more efficacious. Purpose: The purpose of this study is to compare four types of different attachm-ent systems; two prefabricated and two castable attachments. Materials and Method: A model of lower edentulous arch was constructed ...

  13. Transversal changes in dental arches from non-extraction treatment with self ligating brackets

    OpenAIRE

    Liliana Avila Maltagliati; Yasushi Inoue Myiahira; Liana Fattori; Leopoldino Capelozza Filho; Mauricio Cardoso

    2013-01-01

    OBJECTIVE: The present study aimed at analyzing, with the use of dental casts, the transverse changes of the upper and lower dental arches, after non-extraction orthodontic treatment, with self-ligating brackets. METHODS: The sample comprised 29 patients, all presenting Class I malocclusion with upper and lower crowding of at least 4 mm and treated only with a fixed appliance, without stripping, extraction or distalization. The dental casts were obtained before and after leveling with 0.019 x...

  14. The Influence of heat treatment in orthodontic arches made of stainless steel wire

    Directory of Open Access Journals (Sweden)

    de Biasi R.S.

    2000-01-01

    Full Text Available The austenitic stainless steel of orthodontic wires may undergo phase transformation induced by plastic deformation and heat treatment for stress relief. In order to study these changes, arches were made with 0.0215 x 0.027" orthodontic wires and ferromagnetic resonance measurements were performed. The results showed that the best heat treatment for recovery of the austenitic phase seems to be at 450 °C for 3 min.

  15. Accuracy of complete-arch dental impressions: a new method of measuring trueness and precision

    OpenAIRE

    Ender, Andreas; Mehl, Albert

    2013-01-01

    STATEMENT OF PROBLEM: A new approach to both 3-dimensional (3D) trueness and precision is necessary to assess the accuracy of intraoral digital impressions and compare them to conventionally acquired impressions. PURPOSE: The purpose of this in vitro study was to evaluate whether a new reference scanner is capable of measuring conventional and digital intraoral complete-arch impressions for 3D accuracy. MATERIAL AND METHODS: A steel reference dentate model was fabricated and measured with a...

  16. A modified total arch replacement combined with a stented elephant trunk implantation for acute type A dissection under deep hypothermic circulatory arrest and selective antegrade cerebral perfusion

    OpenAIRE

    Yang, Su-Min; Xu, Ping; Cheng-xiang LI; Huang, Qiang; Gao, Hong-Bo; Li, Zhen-Fu; Chang, Qing

    2014-01-01

    Objectives Since the optimal management of patients with acute aortic dissection is unclear, this study analyzed total arch replacement combined with stented elephant trunk implantation in the treatment of acute type A aortic dissection. Methods Between February 2008 and February 2013, 86 consecutive patients admitted to our hospital for acute type A dissection underwent total arch replacement combined with stented elephant trunk implantation under deep hypothermic circulatory arrest. The Ben...

  17. Influence of Custom Trays, Dual-Arch Passive, Flexed Trays and Viscosities of Elastomeric Impression Materials on Working Dies

    Science.gov (United States)

    Kohli, Shivani; Kalsi, Rupali

    2016-01-01

    Introduction Dual arch impression technique signifies an essential improvement in fixed prosthodontics and has numerous benefits over conventional impression techniques. The accuracy of working dies fabricated from dual arch impression technique remains in question because there is little information available in the literature. Aim This study was conducted to compare the accuracy of working dies fabricated from impressions made from two different viscosities of impression materials using metal, plastic dual arch trays and custom made acrylic trays. Materials and Methods The study samples were grouped into two groups based on the viscosity of impression material used i.e. Group I (monophase), whereas Group II consisted of Dual Mix technique using a combination of light and heavy body material. These were further divided into three subgroups A, B and C depending on the type of impression tray used (metal dual arch tray, plastic dual arch tray and custom made tray). Measurements of the master cast were made using profile projector. Descriptive statistics like mean, Standard Deviation (SD) were calculated for all the groups. One way analysis of variance (ANOVA) was used for multiple group comparisons. A p-value of 0.05 or less was considered statistically significant. Results The gypsum dies obtained with the three types of impression trays using two groups of impression materials were smaller than the master models in dimensions. Conclusion The plastic dual arch trays produced dies which were the least accurate of the three groups. There was no significant difference in the die dimensions obtained using the two viscosities of impression materials. PMID:27437342

  18. Experimental Study on Soil Arching Effect in Pile-supported Reinforced Embankment Under Dynamic Train Loads with Large Number of Vibration Cycles%大振次列车动荷载作用下桩网加筋路堤土拱效应模型试验研究

    Institute of Scientific and Technical Information of China (English)

    陈仁朋; 汪焱卫; 陈金苗; 边学成

    2015-01-01

    Through a full scale model test on pile-supported reinforced embankment,by exerting 1.2 m times dynamic axle load to the embankment under the condition of a train moving at a speed of 324 km/h,this paper studied the variation of dynamic soil stress with vibration times at the level of pile caps and in the 3.2 m em-bankment range.The development of the soil arch under long-term dynamic load was analyzed as well.The ex-periment results showed that when the pile-soil differential settlement was relatively large,the pile caps sus-tained nearly 90 percent of static load and dynamic load.As the soil arch strengthened the transmission of the dynamic stress in the embankment to the pile cap,the Boussinesq equation was not applicable to the calculation of distribution of dynamic stress in the embankment.Under long-term dynamic loads,the dynamic pile-soil stress ratio decreased,but the decrease was slight,indicating minor degeneration of the soil arch.%通过桩网加筋路堤足尺模型试验,研究速度324 km/h 时列车120万次轮轴动荷载作用下,桩帽高度位置和3.2 m 路基范围内动土压力随振次的变化规律,分析长期动荷载作用下土拱演化规律。试验结果表明:桩土差异沉降较大时,桩帽承担约90%的动荷载和静荷载,土拱加强了路基中动应力往桩帽的传递,路基中动应力分布按 Boussinesq 公式计算不合理;长期动荷载作用下,桩土动应力比减小,但幅度变化不大,说明土拱弱化不明显。

  19. Microsimulations of Arching, Clogging, and Bursty Exit Phenomena in Crowd Dynamics

    CERN Document Server

    Castro, Francisco Enrique Vicente G

    2015-01-01

    We present in this paper the behavior of an artificial agent who is a member of a crowd. The behavior is based on the social comparison theory, as well as the trajectory mapping towards an agent's goal considering the agent's field of vision. The crowd of artificial agents were able to exhibit arching, clogging, and bursty exit rates. We were also able to observe a new phenomenon we called double arching, which happens towards the end of the simulation, and whose onset is exhibited by a "calm" density graph within the exit passage. The density graph is usually bursty at this area. Because of these exhibited phenomena, we can use these agents with high confidence to perform microsimulation studies for modeling the behavior of humans and objects in very realistic ways.

  20. Construction Simulation and Real-Time Control for High Arch Dam

    Institute of Scientific and Technical Information of China (English)

    ZHONG Denghua; REN Bingyu; WU Kangxin

    2008-01-01

    A method of combining dynamic simulation with real-time control was proposed to fit the randomness and uncertainty in the high arch dam construction process. The mathematical logic model of high arch dam construction process was established. By combining dynamic con-struction simulation with schedule analysis, the process of construction schedule forecasting and analysis based on dynamic simulation was studied. The process of real-time schedule control was constructed and some measures for dynamic adjustment and control of construction schedule were provided. A system developed with the method is utilized in a being constructed hydroelectric pro-ject located at the Yellow River in northwest China, which can make the pouring plan of the dam in the next stage (a month, cluarter or year) to guide the practical construction. The application result shows that the system provides an effective technical support for the construction and manage-ment of the dam.

  1. Branched and fenestrated options to treat aortic arch aneurysms.

    Science.gov (United States)

    Maurel, Blandine; Mastracci, Tara M; Spear, Rafaelle; Hertault, Adrien; Azzaoui, Richard; Sobocinski, Jonathan; Haulon, Stephan

    2016-10-01

    Conventional surgical repair of aortic arch aneurysms using cardiopulmonary bypass and hypothermic circulatory arrest remains the gold standard, however it is associated with a substantial mortality and morbidity rate, especially in the elderly. Hybrid techniques avoid aortic cross-clamping and circulatory arrest, but are of limited use and are only applicable to selected patients. The development of new devices to treat aortic arch aneurysms endovascularly has the potential to offer a treatment modality to patients unfit for an open repair. We present the challenges specific to endovascular arch repair based on our experience and the literature available from the first experience in 1999 to the third generation graft currently commonly used. Following an initial learning curve associated with the use of the third generation arch branch device, along with careful patient selection and operator experience, early results are promising. Technical success was achieved in all cases, there was no early mortality and strokes were noted in 11%. As with branched and fenestrated technology for thoracoabdominal aneurysm repair, the use of total endovascular repair for arch pathology will require an evolution in endovascular practice and device design. However, at present, the early use of the latest generation device offers a novel approach to patients who previously had no surgical options. PMID:27332680

  2. [Evaluation of the timing of orthodontic arch expansion and graft in cleft lip and palate].

    Science.gov (United States)

    Chang, Le; Wang, Yingnan; Liu, Hongyan

    2016-04-01

    Maxillary transverse growth is inhibited by congenital cleft, early surgical scar strain, and oppression of lipmuscles in patients with cleft lip and palate. Clinical manifestations have shown severely constricted maxilla, insufficientmaxillary width, mismatch of upper and lower dental arches, and crossbite. Alveolar bone graft and arch expansion can effectively correct the deficiency in maxillary width. This paper discusses the timing and success rate of alveolar bone graft, as wellas the relationship between alveolar bone graft and arch expansion. Secondary alveolar bone graft is optimally performed beforepermanent canine eruption, especially when the teeth have formed between half and three quarters of their roots. Rapid maxillaryexpansion prior to alveolar bone graft is beneficial because this process increases the gap of the cleft, expands bone graft, andreduces the difficulty. However, the stability of this process remains controversial. Small-scale studies have reported that rapidmaxillary expansion after alveolar bone graft can open the midpalatal suture without bone graft loss. Slow maxillary expansioncan provide continuous light forces to reconstruct the bone. However, these studies are coordinated with fixed orthodontictreatment. Further research is necessary to determine the effects of maxillary expansion on long-term stability of teeth. PMID:27337934

  3. Seismic analysis of high arch dams considering contraction-peripheral joints coupled effects

    Science.gov (United States)

    Hariri-Ardebili, Mohammad; Mirzabozorg, Hasan; Kianoush, M.

    2013-09-01

    Dam-reservoir interaction is one of the classic coupled problems in which two various environments with different physical characteristics are in contact with each other on interface boundary. Consideration of such interaction is important in design of new dams as well as on safety evaluation of the existing ones. In the present study, the effect of hydrodynamic pressures at various reservoir operational levels on seismic behavior of an arch dam is investigated. Dez ultra-high arch dam in Iran was selected as case study and all contraction and peripheral joints were simulated using node-to-node contact elements which have the ability of opening/closing and tangential movement. In addition, stage construction effects including joint grouting based on available construction reports were considered. The reservoir was assumed to be compressible and the foundation rock was modeled to account for its flexibility. The TABAS earthquake record was used to excite the finite element model of dam-reservoir-foundation system. It was found that dam-reservoir interaction has significant structural effects on the system and generally, operating the considered arch dam at different water levels can highly affects the distribution of the crack prone area under the maximum credible earthquake.

  4. Mandibular dental arch changes associated with treatment of crowding using self-ligating and conventional brackets.

    Science.gov (United States)

    Pandis, Nicholas; Polychronopoulou, Argy; Makou, Margarita; Eliades, Theodore

    2010-06-01

    The purpose of this study was to investigate the effect of treatment of mandibular crowding with self-ligating and conventional brackets on dental arch variables. Fifty-six patients were selected from a pool of subjects satisfying the following inclusion criteria: non-extraction treatment in the mandibular or maxillary arches, eruption of all mandibular teeth, no spaces and an irregularity index greater than 2 mm in the mandibular arch, and no adjunct treatment such as etxra- or intraoral appliances. The patients were assigned to two groups: one group received treatment with the self-ligating bracket and the other with a conventional edgewise appliance, both with a 0.022 inch slot. Lateral cephalometric radiographs obtained at the beginning (T1) and end (T2) of treatment were used to assess the alteration in mandibular incisor inclination, and measurements of intercanine and intermolar widths were made on dental casts to investigate changes associated with the correction. The results were analysed with bivariate and multivariate linear regression analysis in order to examine the effect of the bracket systems on arch width or lower incisor inclination, adjusting for the confounding effect of demographic and clinical characteristics. An alignment-induced increase in the proclination of the mandibular incisors was observed for both groups; no difference was identified between self-ligating and conventional brackets with respect to this parameter. Likewise, an increase in intercanine and intermolar widths was noted for both bracket groups; the self-ligating group showed a higher intermolar width increase than the conventional group, whereas the amount of crowding and Angle classification were not significant predictors of post-treatment intermolar width. PMID:19959610

  5. Sagittal changes in lower incisors by the use of lingual arch

    Directory of Open Access Journals (Sweden)

    Helen Carolina Becker Letti

    2013-06-01

    Full Text Available OBJECTIVE: The objective of this study was to evaluate a sagittal variation on the lower incisors with the use of the lingual arch on the transition from mixed to permanent dentition. METHODS: The sample was constituted of 44 Caucasian patients (26 girls and 18 boys, divided in two groups: CG, control group, monitoring the lower arch space with no orthodontic/orthopedic treatment during the rated period (n = 14; EG, experimental group, presenting anterior inferior mild crowding and installation of the lingual arch for space maintenance (n = 30. The position of the lower incisors was analyzed on computerized cephalometric tracings performed at the beginning of the monitoring (T1 and at the end, on the permanent dentition (T2. In order to evaluate the position of the incisors it was used Tweed and Steiner measurements: IMPA, 1.NB and 1-NB. The alterations were analyzed through the "t" test for paired samples, while the differences between the groups were analyzed through the "t" test for independent samples, as for sexual dimorphism. RESULTS: The values in T2 were greater in relation to T1 for all measurements on EG (IMPA, p = 0.038; 1.NB, p = 0.007 and 1-NB, p < 0.0001. On comparing the differences (T2-T1 between CG and EG, it can be gauged differences significantly superior for measure 1.NB (p = 0.002 and 1-NB (p < 0.0001 on EG. There was no statisticaly significant difference between genres. CONCLUSION: It was concluded that the lower incisors were projected after using the lingual arch to control the space on the transition from mixed to permanent dentition, however, within acceptable standards, not having difference between genres.

  6. [A treatment chart adapted to the arch form].

    Science.gov (United States)

    Bocquet-Moreau, E; Danguy, Ch; Bertrand, J; Danguy, M

    2005-12-01

    Arch wires used in orthodontic treatment must conform to the shape of the dental arches so that in their final positions teeth will be set in a pathway of neuromuscular equilibrium. However, sometimes distortions of the alveoli deform the shape of the arch. In such cases the treatment charts constructed on the actual alveolo-dental relationship will not reflect desired objectives. We believe that the transverse muco-gingival dimension Andrews called the Wala line responds better to therapeutic requirements. Moreover, molar attachments, key elements of a full-banded appliance, are in harmony with it. So the type of chart that the authors propose for use with the Straight Wire technique, one based on the Wala line, will help orthodontists place teeth at the conclusion of orthodontic treatment in the best possible relationships to patients' specific anatomic configurations. PMID:16471375

  7. In-Plane MEMS Shallow Arch Beam for Mechanical Memory

    Directory of Open Access Journals (Sweden)

    Md Abdullah Al Hafiz

    2016-10-01

    Full Text Available We demonstrate a memory device based on the nonlinear dynamics of an in-plane microelectromechanical systems (MEMS clamped–clamped beam resonator, which is deliberately fabricated as a shallow arch. The arch beam is made of silicon, and is electrostatically actuated. The concept relies on the inherent quadratic nonlinearity originating from the arch curvature, which results in a softening behavior that creates hysteresis and co-existing states of motion. Since it is independent of the electrostatic force, this nonlinearity gives more flexibility in the operating conditions and allows for lower actuation voltages. Experimental results are generated through electrical characterization setup. Results are shown demonstrating the switching between the two vibrational states with the change of the direct current (DC bias voltage, thereby proving the memory concept.

  8. Game model of safety monitoring for arch dam deformation

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Arch dam deformation is comprehensively affected by water pressure,temperature,dam’s structural behavior and material properties as well as other factors.Among them the water pressure and temperature are external factors(source factors) that cause dam deformation,and dam’s structural behavior and material properties are the internal factors of deformation(resistance factors).The dam deformation is the result of the mutual game playing between source factors and resistance factors.Therefore,resistance factors of structure and materials that reflect resistance character of arch dam structure are introduced into the traditional model,where structure factor is embodied by the flexibility coefficient of dam body and the maximum dam height,and material property is embodied by the elastic modulus of dam.On the basis of analyzing the correlation between dam deformation and resistance factors,the game model of safety monitoring for arch dam deformation is put forward.

  9. LANGER’S AXILLARY ARCH AND ITS CLINICAL IMPLICATIONS

    Directory of Open Access Journals (Sweden)

    Jyothi K C

    2014-09-01

    Full Text Available Introduction: The axillary arch muscle of Langer is the most common anatomical variant of axillary musculature which is of clinical and surgical importance. It may lead to neurovascular compression syndrome in the cervicoaxillary region and can be misinterpreted while examining axilla and also impairs movements of shoulder joint. Observation: During routine dissection of axilla for undergraduate teaching, an unusual muscular slip in the left axilla was observed .The muscular slip was extending from lattisimus dorsi muscle to undersurface of pectoralis major muscle, arching over axillary vessels and cords of brachial plexus. Conclusion: The axillary arch may cause obstruction to axillary vessels and nerves and may be involved in thoracic outlet syndrome and shoulder instability. The knowledge of this muscular variant could help to minimize intraoperative complications related to surgeries in or nearby axilla such as mastectomy, breast reconstruction and axillary lymphadenectomy or lymph node biopsy.

  10. 3D MODELLING OF PROPHYLACTIC FOOTWEAR FOR A HIGH ARCHED FOOT

    Directory of Open Access Journals (Sweden)

    COSTEA Mariana

    2016-05-01

    Full Text Available This article approaches the methodology of designing customized footwear for high arched foot. The authors propose to reconsider the classical structure of footwear bottom components for people with high arched foot and recommend incorporating custom components, with the role of compensation or adjustment. This study continues the authors’ research, starting from a foot’s 3D shape obtained by 3D scanning, the anthropometrical and biomechanical parameters, shoe lasts’ 3D modelling and continuing with 3D footwear design. Including customized orthosis can help to stop the evolution of abnormalities, diminishes sensations of pain during walking and improves performance in various physical activities carried out during the day, walking, running, and standing. The prophylactic footwear has to meet four main requirements: to protect the foot and ankle during walking and static; to ensure the normal resistance systems (bones, muscle and joint of the foot; to prevent the installation of irreversible structural changes by reducing stress on the foot; to contribute to increased performance in conducting regular physical activity. It is presented the steps of modelling an orthosis, a virtual simulation of its cutting process, followed by the integration and development of the insole, filling and sole for a customized shoe. Delcam Crispin CAD system and its applications for orthopaedics are used to design the bottom components of prophylactic footwear for a high arched foot.

  11. Fatigue Performance Assessment of Composite Arch Bridge Suspenders Based on Actual Vehicle Loads

    Directory of Open Access Journals (Sweden)

    Bin Chen

    2015-01-01

    Full Text Available In the through arch bridges, the suspenders are the key components connecting the arch rib and the bridge deck in the middle, and their safety is an increasing focus in the field of bridge engineering. In this study, various vehicle traffic flow parameters are investigated based on the actual vehicle data acquired from the long-term structural health monitoring system of a composite arch bridge. The representative vehicle types and the probability density functions of several parameters are determined, including the gross vehicle weight, axle weight, time headway, and speed. A finite element model of the bridge structure is constructed to determine the influence line of the cable force for various suspenders. A simulated vehicle flow, generated using the Monte Carlo method, is applied on the influence lines of the target suspender to determine the stress process, and then the stress amplitude spectrum is obtained based on the statistical analysis of the stress process using the rainflow counting method. The fatigue performance levels of various suspenders are analyzed according to the Palmgren-Miner linear cumulative damage theory, which helps to manage the safety of the suspenders.

  12. Modeling and forecasting crude oil markets using ARCH-type models

    Energy Technology Data Exchange (ETDEWEB)

    Cheong, Chin Wen [Research Centre of Mathematical Sciences, Faculty of Information Technology, Multimedia University, 63100 Cyberjaya, Selangor (Malaysia)

    2009-06-15

    This study investigates the time-varying volatility of two major crude oil markets, the West Texas Intermediate (WTI) and Europe Brent. A flexible autoregressive conditional heteroskedasticity (ARCH) model is used to take into account the stylized volatility facts such as clustering volatility, asymmetric news impact and long memory volatility among others. The empirical results indicate that the intensity of long-persistence volatility in the WTI is greater than in the Brent. It is also found that for the WTI, the appreciation and depreciation shocks of the WTI have similar impact on the resulting volatility. However, a leverage effect is found in Brent. Although both the estimation and diagnostic evaluations are in favor of an asymmetric long memory ARCH model, only the WTI models provide superior in the out-of-sample forecasts. On the other hand, from the empirical out-of-sample forecasts, it appears that the simplest parsimonious generalized ARCH provides the best forecasted evaluations for the Brent crude oil data. (author)

  13. Modeling and forecasting crude oil markets using ARCH-type models

    International Nuclear Information System (INIS)

    This study investigates the time-varying volatility of two major crude oil markets, the West Texas Intermediate (WTI) and Europe Brent. A flexible autoregressive conditional heteroskedasticity (ARCH) model is used to take into account the stylized volatility facts such as clustering volatility, asymmetric news impact and long memory volatility among others. The empirical results indicate that the intensity of long-persistence volatility in the WTI is greater than in the Brent. It is also found that for the WTI, the appreciation and depreciation shocks of the WTI have similar impact on the resulting volatility. However, a leverage effect is found in Brent. Although both the estimation and diagnostic evaluations are in favor of an asymmetric long memory ARCH model, only the WTI models provide superior in the out-of-sample forecasts. On the other hand, from the empirical out-of-sample forecasts, it appears that the simplest parsimonious generalized ARCH provides the best forecasted evaluations for the Brent crude oil data. (author)

  14. Variation of the X-ray non-thermal emission in the Arches cloud

    CERN Document Server

    Clavel, Maïca; Terrier, R; Tatischeff, V; Maurin, G; Ponti, G; Goldwurm, A; Decourchelle, A

    2014-01-01

    The origin of the iron fluorescent line at 6.4 keV from an extended region surrounding the Arches cluster is debated and the non-variability of this emission up to 2009 has favored the low-energy cosmic-ray origin over a possible irradiation by hard X-rays. By probing the variability of the Arches cloud non-thermal emission in the most recent years, including a deep observation in 2012, we intend to discriminate between the two competing scenarios. We perform a spectral fit of XMM-Newton observations collected from 2000 to 2013 in order to build the Arches cloud lightcurve corresponding to both the neutral Fe Kalpha line and the X-ray continuum emissions. We reveal a 30% flux drop in 2012, detected with more than 4 sigma significance for both components. This implies that a large fraction of the studied non-thermal emission is due to the reflection of an X-ray transient source.

  15. The effect of material properties on the seismic performance of Arch Dams

    Science.gov (United States)

    Sevim, B.

    2011-08-01

    The paper investigates the effect of material properties on the seismic performance of arch dam-reservoir-foundation interaction systems based on the Lagrangian approach using demand-capacity ratios. Type-5 arch dam is selected as a numerical application. The linear time history analyses of the arch dam-reservoir-foundation interaction system are carried out for different material properties. The foundation is taken into account as massless; behaviour of the reservoir is assumed to be linearly elastic, inviscid and irrotational. The north-south component of the Erzincan earthquake in 1992 is chosen as a ground motion. Dynamic equations of motions obtained from 3-D finite element modelling of the coupled system are solved by using the Newmark integration algorithm. The damage levels of the coupled system for the different material properties are demonstrated by using demand-capacity ratios and cumulative inelastic durations. The time histories and maximum values of the displacements and principal stresses, and performance curves, are obtained from linear analyses. It is clearly seen from the study that the different material properties affect the seismic behaviour of the dam.

  16. The effect of material properties on the seismic performance of Arch Dams

    Directory of Open Access Journals (Sweden)

    B. Sevim

    2011-08-01

    Full Text Available The paper investigates the effect of material properties on the seismic performance of arch dam-reservoir-foundation interaction systems based on the Lagrangian approach using demand-capacity ratios. Type-5 arch dam is selected as a numerical application. The linear time history analyses of the arch dam-reservoir-foundation interaction system are carried out for different material properties. The foundation is taken into account as massless; behaviour of the reservoir is assumed to be linearly elastic, inviscid and irrotational. The north-south component of the Erzincan earthquake in 1992 is chosen as a ground motion. Dynamic equations of motions obtained from 3-D finite element modelling of the coupled system are solved by using the Newmark integration algorithm. The damage levels of the coupled system for the different material properties are demonstrated by using demand-capacity ratios and cumulative inelastic durations. The time histories and maximum values of the displacements and principal stresses, and performance curves, are obtained from linear analyses. It is clearly seen from the study that the different material properties affect the seismic behaviour of the dam.

  17. Geology of the Juanita Arch quadrangle, Mesa county, Colorado

    Science.gov (United States)

    Shoemaker, Eugene M.

    1954-01-01

    The Juanita Arch quadrangle is one of eighteen 7 1/2-minute quadrangles covering the principal carnotite-producing area of southwestern Colorado. The geology of these quadrangles was mapped by the U.S. Geological Survey for the Atomic Energy Commission as part of a comprehensive study of carnotite deposits. The rocks exposed in the eighteen quadrangles consist of crystalline rocks of pre-Cambrian age and sedimentary rocks that range in age from late Paleozoic to Quaternary. Over much of the area the sedimentary rocks are flat lying, but in places the rocks are disrupted by high-angle faults and northwest-trending folds. Conspicuous among the folds are large anticlines having cores of intrusive salt and gypsum. Most of the carnotite deposits are confined to the Salt Wash sandstone member of the Jurassic Morrison formation. Within this sandstone, most of the deposits are spottily distributed through an arcuate zone known as the "Uravan Mineral Belt". Individual deposits range in size from irregular masses containing only a few tons of ore ro large, tabular masses containing many thousands of tons. The ore consists largely of sandstone selectively impregnated and in part replaced by uranium and vanadium minerals. Most of the deposits appear to be related to certain sedimentary structures in sandstone of favorable construction.

  18. Management of hypoplastic aortic arch associated with neonatal coarctation.

    Science.gov (United States)

    Caspi, J; Ilbawi, M N; Muster, A; Roberson, D; Arcilla, R

    1994-12-01

    Controversy still exists as to whether hypoplastic aortic arch frequently associated with neonatal coarctation, should be enlarged at the time of coarctation repair. To determine the indications for and the outcome of repair of hypoplastic aortic arch, pre- and postoperative angiograms/echocardigraphy of 77 cases with isolated (n = 25, Group 1) or complex (n = 52, Group 2) neonatal coarctation operated upon between 1/80 and 12/89 were reviewed. Age was 5-14 days (mean 8 +/- 1.6). Aortic arch/ascending aorta diameter ratio (AR/AA) as a measure of the degree of aortic arch hypoplasia was 0.39-0.64 (0.52 +/- 0.04) in isolated and 0.15-0.47 (0.34 +/- 0.06) in complex coarctation (p < 0.05). Left subclavian flap aortoplasty was used in 72 patients; alone in 25, in combination with pulmonary artery banding in 43 patients, and simultaneously with intracardiac repair in 4 patients. Extensive reconstruction of aortic arch and coarctation with synthetic patch was performed in the remaining 5 patients (AR/AO = 0.16 +/- 0.03) using cardiopulmonary by-pass at the time of intracardiac repair. Operative mortality was 2/76 (2.5%). Follow-up is 6.6 +/- 1.4 years. Recoarctation occurred in 3 patients (4%). AR/AA increased to 0.86 +/- 0.1 in isolated (p < 0.05 vs preoperative) and to 0.7 +/- 0.1 in complex coarctation (p < 0.05 vs preoperative). In the majority of cases, hypoplastic aortic arch associated with coarctation grows satisfactorily following simple repair of coarctation with no significant residual narrowing.(ABSTRACT TRUNCATED AT 250 WORDS)

  19. Photographs of dental casts or digital models: rating dental arch relationships in bilateral cleft lip and palate.

    NARCIS (Netherlands)

    Leenarts, C.M.; Bartzela, T.N.; Bronkhorst, E.M.; Semb, G.; Shaw, W.C.; Katsaros, C.; Kuijpers-Jagtman, A.M.

    2012-01-01

    Yardsticks have been developed to measure dental arch relations in cleft lip and palate (CLP) patients as diagnostic proxies for the underlying skeletal relationship. Travelling with plaster casts to compare results between CLP centres is inefficient so the aim of this study was to investigate the r

  20. Planning and Analysis of an Arched Indoor Stadium

    Directory of Open Access Journals (Sweden)

    Alice T V

    2014-04-01

    Full Text Available This paper deals with planning and designing of a multilevel indoor stadium with hanging table tennis court and Olympic standard swimming pool. In order to support the large span the stadium is designed as an arched structure. The materials for the construction are chosen so as to have a minimum carbon di-oxide foot print. Static and earthquake analysis were done by using STAAD.Pro V8i. The paper also does a comparison between arched structure and plane frame structure.

  1. The shortened dental arch: a review of the literature.

    Science.gov (United States)

    Armellini, Debora; von Fraunhofer, J Anthony

    2004-12-01

    The functional demands of patients are highly variable and individual, requiring dental treatment to be tailored to the individual's needs and adaptive capability. The World Health Organization indicates that a functional, esthetic, natural dentition has at least 20 teeth, while the literature indicates that dental arches comprising the anterior and premolar regions meet the requirements of a functional dentition. The English-language peer-reviewed literature pertaining to the short dental arch (SDA) was identified through the Medline search engine covering the period between 1966 and the present and critically reviewed. This treatment option for the partially dentate patient may provide oral functionality, improved oral hygiene, comfort, and, possibly, reduced costs.

  2. Stabilization of medial longitudinal foot arch by peroneus longus transfer.

    Science.gov (United States)

    Lui, T H

    2016-06-01

    The mechanical integrity of the medial longitudinal arch depends on the dynamic support of muscles and the static support of ligaments. Although the posterior tibial tendon is the main dynamic stabilizer of the arch, the static structures provide the most support especially while the person is standing. After rupture of the posterior tibial tendon, the spring ligament may be compromised under increased stress and leads to talar derotation and peritalar subluxation. Surgical repair of the spring ligament has become an important adjunct to treating posterior tibial tendon abnormalities. A technique of peroneus longus transfer to augment the static stabilizers of the medial column is described in this article. PMID:27058034

  3. Excitation of Arch and Suspension Bridges by Subwires

    Directory of Open Access Journals (Sweden)

    Noriaki Hiwatashi

    1993-01-01

    Full Text Available A force generation method using a subwire for arch and suspension bridges is proposed. The subwire is connected to the arch or the cable of the bridge through rollers. The uniform force produced by pulling and releasing the pretensioned subwires acts on the bridge as an externalforce. A new device called “the resonance force generator” is also developed to excite the bridges by applying a small force. To verify the proposed concept, a stress ribbon bridge was excited with the resonance force generator.

  4. Excitation of Arch and Suspension Bridges by Subwires

    OpenAIRE

    Noriaki Hiwatashi; Yoji Mizuta; Yutaka Ishihara; Itio Hirai

    1993-01-01

    A force generation method using a subwire for arch and suspension bridges is proposed. The subwire is connected to the arch or the cable of the bridge through rollers. The uniform force produced by pulling and releasing the pretensioned subwires acts on the bridge as an externalforce. A new device called “the resonance force generator” is also developed to excite the bridges by applying a small force. To verify the proposed concept, a stress ribbon bridge was excited with the resonance force ...

  5. Aortic arch in neonates with esophageal atresia: Preoperative assessment using CT

    Energy Technology Data Exchange (ETDEWEB)

    Day, D.L.

    1985-04-01

    Preoperative localization of the aortic arch is important in infants with esophageal atresia to prevent morbidity and death from an ipsilateral surgical approach. Computed tomography is an accurate, noninvasive technique for determining the position of the aortic arch.

  6. The surgical importance of an axillary arch in sentinel node biopsy.

    LENUS (Irish Health Repository)

    Ridgway, P F

    2011-03-01

    When Carl Langer described the aberrant axillary arch in 1846 its relevance in sentinel node biopsy (SNB) surgery could not have been contemplated. The authors define an incidence and elucidate relevance of the arch in SNB of the axilla.

  7. Influence of space of double row piles on soil arching effect

    Directory of Open Access Journals (Sweden)

    Zhao bo

    2015-02-01

    Full Text Available FLAC3d software, based on continuous theory, is used to analysis influence of space of double row piles on soil arching effect. The result shows that different from single row pile, double row piles will produce soil arching effect at front pile and rear pile severally, this phenomenon is called multiple soil arching effect; the residual load of front of front row pile will increase,the soil arch zone and the soil arching effect will decrease with the continuous increase of double row pile spacing.At the same time the soil arching effect of rear pile decreases, while the soil arching effect of front pile increases and finally the soil arching effect between front pile and rear pile will be equal.

  8. Rock-Arch Instability Characteristics of the Sandstone Plate under Different Loading Conditions

    OpenAIRE

    Shuren Wang; Paul Hagan; Baowen Hu; Kanchana Gamage; Cheng Yan; Dianfu Xu

    2014-01-01

    Under the concentrated loading and the uniform loading, the tests on the brittle fracture and the hinged arching until the rock-arch instability of the sandstone plate were conducted using self-developed loading device, and the sensitivity of influent factors on the rock-arch failure was analyzed by numerical test based on the particle flow code (PFC). The results showed that sandstone plate instability presented four phases: small deformation elastic stage, brittle fracture arching stage, ...

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

    Science.gov (United States)

    2010-10-01

    ... 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 and... 49 Transportation 4 2010-10-01 2010-10-01 false Arch tubes, water bar tubes, circulators...

  10. File list: Pol.Emb.50.AllAg.Maxillary_arch_junction [Chip-atlas[Archive

    Lifescience Database Archive (English)

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    Lifescience Database Archive (English)

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  8. File list: DNS.Emb.10.AllAg.Maxillary_arch_junction [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  9. File list: His.Emb.10.AllAg.Maxillary_arch_junction [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  10. File list: Pol.Emb.05.AllAg.Maxillary_arch_junction [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  11. File list: ALL.Emb.50.AllAg.Maxillary_arch_junction [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  12. File list: Pol.Emb.20.AllAg.Maxillary_arch_junction [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  13. Double aortic arches, esophageal atresia and tracheal compression

    OpenAIRE

    Majid Yameen; Warade Monali; Aziz Zarina; Karthik G

    2009-01-01

    We report a case of double aortic arch in a 12-month-old male infant well delineated on 64 slice computed tomography scan. It formed a complete vascular ring around the trachea compressing it. The symptoms resolved after surgical division of the ring.

  14. 3D Stretchable Arch Ribbon Array Fabricated via Grayscale Lithography

    Science.gov (United States)

    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.

  15. Athenry Castle, exterior east wall, door, jamb and arch

    OpenAIRE

    O'Donovan, Danielle

    2001-01-01

    Jamb and arch of pointed door that might be called Transitional or Early English in style. The mouldings perhaps too large and simple to be Early English. Moulding comprises: angle roll flanked at either side by quarter roll, and to front face by hollow chamfer.

  16. Dental arch diameters and relationships to oral habits.

    Science.gov (United States)

    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 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.

  17. UNILATERAL INCOMPLETE SUPERFICIAL PALMAR ARCH: A CASE REPORT

    Directory of Open Access Journals (Sweden)

    Subhankar Chakraborty

    2015-12-01

    Full Text Available The functional importance of hand is revealed by its rich vascularity contributed by superficial and deep palmar arches (SPA and DPA.Superficial palmar arch is located superficial to flexor tendons, and deep palmar arch deep to lumbrical muscles. Variations are found more often in SPA than DPA, later being more or less constant. During routine undergraduate dissection, we observed, unilateral incomplete SPA being formed by superficial palmar branches of ulnar and radial artery in the right hand of a male cadaver. These two arteries remained independent without anastomosis forming incomplete arch (SPA.The superficial branch of ulnar artery entered hand superficial to flexor retinaculum and supplied middle, ring and little finger by three branches. The superficial branch of radial artery via its two branches supplied index finger and thumb. Classical SPA formation was seen on left side. The presence of an incomplete SPA as in this case is a potential danger in RA harvesting for CABG.Variations in SPA play a pivotal role in microvascular surgical procedures of hand, RAinterventions and arterial graft applications.

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

    Energy Technology Data Exchange (ETDEWEB)

    Kaganov, G. M.; Volkov, V. I.; Uchevatkin, A. A. [FGOU VPO Moscow State University of the Natural Environment (Russian Federation)

    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.

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

    Science.gov (United States)

    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.

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

    Energy Technology Data Exchange (ETDEWEB)

    Mahnken, Andreas H., E-mail: mahnken@med.uni-marburg.de [University Hospital Giessen and Marburg, Philipps University of Marburg, Department of Diagnostic Radiology (Germany); Hoffman, Andras; Autschbach, Ruediger; Damberg, Anneke L. M., E-mail: anneke.damberg@rwth-aachen.de [University Hospital RWTH Aachen, Department of Thoracic, Cardiac and Vascular Surgery (Germany)

    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.

  1. Intraplate deformation of the Al Qarqaf Arch and the southern sector of the Ghadames Basin (SW Libya)

    Science.gov (United States)

    Carruba, Stefano; Perotti, Cesare; Rinaldi, Marco; Bresciani, Ilenia; Bertozzi, Giuseppe

    2014-09-01

    The structural evolution of the Al Qarqaf Arch (Libya) and the southern sector of the Ghadames Basin were reconstructed by the integration of remote sensing analysis, 2D seismic lines, well log data and geological maps. The Al Qarqaf Arch (Libya) is a wide, gentle warping of pre-Cambrian and Palaeozoic rocks that forms the southern boundary of the Ghadames Basin, a large Palaeozoic intracratonic basin of the Saharan Platform. Surface and subsurface analyses revealed the presence of different phases of intracratonic deformations, related to the Al Qarqaf Arch uplift and Ghadames Basin development. Extensional tectonic phases prevailed in the study area up until the Devonian, while compressional folding and structural inversion affected the region during Late Carboniferous and Mesozoic, indicating that compressional horizontal stresses affected the plate interior, giving rise to intraplate tectonics. Three major unconformities (Intra-Silurian, Silurian-Devonian transition and Upper Carboniferous unconformities) outline these tectonic events related to the upwarping of the arch and the downwarping of the basin.

  2. Proactive monitoring and adaptive management of social carrying capacity in Arches National Park: an application of computer simulation modeling.

    Science.gov (United States)

    Lawson, Steven R; Manning, Robert E; Valliere, William A; Wang, Benjamin

    2003-07-01

    Public visits to parks and protected areas continue to increase and may threaten the integrity of natural and cultural resources and the quality of the visitor experience. Scientists and managers have adopted the concept of carrying capacity to address the impacts of visitor use. In the context of outdoor recreation, the social component of carrying capacity refers to the level of visitor use that can be accommodated in parks and protected areas without diminishing the quality of the visitor experience to an unacceptable degree. This study expands and illustrates the use of computer simulation modeling as a tool for proactive monitoring and adaptive management of social carrying capacity at Arches National Park. A travel simulation model of daily visitor use throughout the Park's road and trail network and at selected attraction sites was developed, and simulations were conducted to estimate a daily social carrying capacity for Delicate Arch, an attraction site in Arches National Park, and for the Park as a whole. Further, a series of simulations were conducted to estimate the effect of a mandatory shuttle bus system on daily social carrying capacity of Delicate Arch to illustrate how computer simulation modeling can be used as a tool to facilitate adaptive management of social carrying capacity.

  3. Arch of opportunity : Peace country operators expand, undeterred by vandalism

    Energy Technology Data Exchange (ETDEWEB)

    Jaremko, D.

    2006-01-15

    Activity levels in the Peace River Arch (Para) area of northwest Alberta are continuing despite reports of oilfield vandalism. Devon Energy is continuing its development of the 2 trillion cubic feet of original gas in place in the Dunevegan field and is also planning activities in the Triassic halfway formation in the southwest Arch. At depths between 2500 and 2800 metres, initial gas-flow rates from sour wells range from 2 to 5 million cubic feet per day. Devon is also targeting medium gravity oil in the northwest arch, and light gravity oil in the eastern part of the PRA. EnCana is expected to exit 2005 with production of 350 MMcf of gas equivalent per day from the PRA after having drilled more than 200 wells. A number of juniors are also expressing interest in the area. Galleon Energy has increased its focus in the PRA to 9000 barrels of oil equivalent per day and has separated its strategy into 4 areas: multi-zone drilling; a tight gas resource play; light, sweet crude development; and deep exploration in the arch's southwest corner. Talisman Energy has 4 rigs working in the area and plans to spend $168 million in the Grande Prairie area, with plans to drill 85 wells. Details of the Peace Arch Operators Group were provided, who meet with regulatory bodies like the Alberta Energy and Utilities Board (EUB), Alberta Environment, regional governments and the RCMP. A rash of oilfield sabotage in the late 1990s led to notoriety for the area. In October 2005, more sabotage occurred near a drilling rig. Satellite connected, web-interface cameras were installed by Anadarko, the rig's owner. Most people in the area are in favour of development, since oil and gas activity in the area will lead to economic benefits for the region. 3 figs.

  4. CREATIVITY METHODS IN TEACHING THE ARCH-DESIGN STUDIO

    Directory of Open Access Journals (Sweden)

    EIGBEONAN Andrew B.

    2013-01-01

    Full Text Available The aim of this paper is to search and find methods of fostering creativity or ideas relating to creativity in teaching the arch-design studio. Teaching creativity through its methods will be making the students grounded in designing with creativity ideas and therefore we can have professionals that design and build with satisfaction, safety and complementary. It means we can have real buildings and places that satisfy our clients, the society and in harmony with the environment. Although there are similarities in the curricula of training architects all over the world, but educators go about it in their own convenient and suitable ways and styles. The ideas of creativity have been part of architecture from the onset, but are not deligently applied and also not formally incorporated in the curricula of training. The topic is also very relevant and timely as arch-educators and other stakeholders are of the opinion that something has to be done to improve the ways and methods of training architects, especially the teaching of the arch-design studio with regards to creativity. Through exploration of literature and interviews (physical and telephone call this paper finds methods of stimulating creativity ideas in the teaching of arch-design studio. Some of the methods of motivating creativity found in teaching the arch-design studio are: analogy, metaphors, biomimicry, brainstorming, attribute listing, mental map, TRIZ, restrictions, charrette, browsing, excursions, focus groups, other peoples viewpoints, using crazy ideas, using experts, visualizing a goal, working with dreams and images and giving students design tools such as drawings CAD and model making.

  5. Magnetic resonance angiography of the aortic arch and its main arteries directed to the brain with use of head neck coil. With special reference to relation between high position of the aortic arch and kinked vertebral and carotid arteries

    Energy Technology Data Exchange (ETDEWEB)

    Morita, Hitoshi [Saitama Medical School, Moroyama (Japan)

    1996-12-01

    We studied 316 individuals who requested general health examinations (March 1993 to February 1995), and who underwent blood tests, urinalysis and MRA with a head neck coil, and 25 volunteers underwent the same examinations. The head neck coil used covered the head, neck and upper thorax, and each individual coil could transmit and receive signals. Three-dimensional time of flight MRA was employed in the investigation. The saturation pulse was placed in a coronal direction behind the slab to suppress the venous inflow signals. Our results indicate that in all individuals, MRA clearly demonstrated the aorta and its main branches extending up to the circle of Willis. It was possible to rotate the reconstructed 3-D image around the body axis permitting the visualization of secondary or more peripheral branches, depending on their size and direction. The severity of V1 kinking, classified by using the modified Mets criteria, correlated well with advancing age. V1 kinking was first evident in the third decade of life, while kinking of the internal carotid artery appeared in the fourth decade. The highest level of the aortic arch was evaluated in terms of the aorto-C2 (A-C2) distance, i.e., the distance measured from the C2 level, where the vertebral artery curved laterally in the transverse foramen of C2, and the A level, where the upper margin of the aortic arch was highest. Shortening of the A-C2 distance was noted with aging, and a good correlation between increased height of the aortic arch and aging was seen. As compared to conventional contrast arteriography, MRA of the aortic arch and its branch arteries extending into the cranium does provide accurate data. A high position of the aortic arch, buckling of the great vessels, and tortuosity, kinking and coiling of the vertebral and carotid arteries are clearly shown. (K.H.)

  6. Complémentarité et discordances entre sources textuelles et sources archéo-anthropologiques en contexte de crises de mortalit�� par épidémie. Études de cas Complementarity and conflicts between textual and archaeo-anthropological sources in the context of mortality crises from epidemics. Case studies

    Directory of Open Access Journals (Sweden)

    Dominique Castex

    2009-05-01

    Full Text Available Longtemps sources archéologiques et textuelles ont été considérées comme complémentaires, or elles apparaissent bien souvent contradictoires. Actuellement la dépendance de l’archéologie des périodes historiques vis à vis des sources écrites n’est plus vraiment de mise. Progressivement s’élabore une autre manière de concevoir l’interdisciplinarité, l’objectif n’étant plus d’aller chercher dans l’une des sources de quoi valider l’autre mais plutôt de construire en commun des objets de recherche permettant une utilisation conjointe efficace des données et une discussion des résultats. Cette démarche, indispensable à toute analyse des sites historiques, est fondamentale pour l’interprétation des crises de mortalité par épidémie du passé. Elle a sous-tendu différentes études interdisciplinaires récentes liées à des découvertes d’archéologie préventives dans le Berry comme à Bourges (Cher et Issoudun (Indre ainsi que des prospections en archives comme à Lignières-en-Berry (Cher. En raison de leur originalité nous souhaitons présenter ces exemples et les comparer à d’autres sites de victimes d’épidémie à l’étranger (Saint-Benoît de Prague en République tchèque et Venosa en Italie, des sites dont la quantité et la qualité de la documentation ont permis une bonne exploitation et ont d’ores et déjà fourni des premiers résultats en termes d’interprétation. Sans prétendre au traitement exhaustif de chaque site, dont certains sont encore en cours d’étude, notre propos est plus simplement de proposer une réflexion sur quelques aspects de l’archéologie des épidémies, de livrer un certain nombre de questionnements et de discuter de la faisabilité des synthèses des sources écrites et archéologiques. Nos résultats nous permettent d’ores et déjà d’apporter des éclairages nouveaux sur l’histoire des épidémies ; d’une part ils mettent en avant des aspects

  7. The effect of clinical use and sterilization on selected orthodontic arch wires.

    Science.gov (United States)

    Smith, G A; von Fraunhofer, J A; Casey, G R

    1992-08-01

    The effect of clinical use and various sterilization/disinfection protocols on three types of nickel-titanium, and one type each of beta-titanium and stainless steel arch wire was evaluated. The sterilization/disinfection procedures included disinfection alone or in concert with steam autoclave, dry heat, or cold solution sterilization. No clinically significant differences were found between new and used arch wires. The direction of load application to the arch wire and the particular segment of arch wire tested was found to cause substantial differences in generated loads for certain arch wire types.

  8. Numerical analyses in the design of umbrella arch systems

    Institute of Scientific and Technical Information of China (English)

    J. Oke; N. Vlachopoulos; M.S. Diederichs

    2014-01-01

    Due to advances in numerical modelling, it is possible to capture complex support-ground interaction in two dimensions and three dimensions for mechanical analysis of complex tunnel support systems, although such analysis may still be too complex for routine design calculations. One such system is the forepole element, installed within the umbrella arch temporary support system for tunnels, which warrants such support measures. A review of engineering literature illustrates that a lack of design standards exists regarding the use of forepole elements. Therefore, when designing such support, de-signers must employ complex numerical models combined with engineering judgement. With reference to past developments by others and new investigations conducted by the authors on the Driskos tunnel in Greece and the Istanbul metro, this paper illustrates how advanced numerical modelling tools can facilitate understanding of the influences of design parameters associated with the use of forepole ele-ments. In addition, this paper highlights the complexity of the ground-support interaction when simulated with two-dimensional (2D) finite element software using a homogenous reinforced region, and three-dimensional (3D) finite difference software using structural elements. This paper further il-lustrates sequential optimisation of two design parameters (spacing and overlap) using numerical modelling. With regard to capturing system behaviour in the region between forepoles for the purpose of dimensioning spacing, this paper employs three distinctive advanced numerical models:particle codes, continuous finite element models with joint set and Voronoi blocks. Finally, to capture the behaviour/failure ahead of the tunnel face (overlap parameter), 2D axisymmetric models are employed. Finally, conclusions of 2D and 3D numerical assessment on the Driskos tunnel are drawn. The data enriched case study is examined to determine an optimum design, based on the proposed optimisation of

  9. Role of aortic arch vascular mechanics in cardiovagal baroreflex sensitivity.

    Science.gov (United States)

    Klassen, Stephen A; Chirico, Daniele; Dempster, Kylie S; Shoemaker, J Kevin; O'Leary, Deborah D

    2016-07-01

    Cardiovagal baroreflex sensitivity (cvBRS) measures the efficiency of the cardiovagal baroreflex to modulate heart rate in response to increases or decreases in systolic blood pressure (SBP). Given that baroreceptors are located in the walls of the carotid sinuses (CS) and aortic arch (AA), the arterial mechanics of these sites are important contributors to cvBRS. However, the relative contribution of CS and AA mechanics to cvBRS remains unclear. This study employed sex differences as a model to test the hypothesis that differences in cvBRS between groups would be explained by the vascular mechanics of the AA but not the CS. Thirty-six young, healthy, normotensive individuals (18 females; 24 ± 2 yr) were recruited. cvBRS was measured using transfer function analysis of the low-frequency region (0.04-0.15 Hz). Ultrasonography was performed at the CS and AA to obtain arterial diameters for the measurement of distensibility. Local pulse pressure (PP) was taken at the CS using a hand-held tonometer, whereas AA PP was estimated using a transfer function of brachial PP. Both cvBRS (25 ± 11 vs. 19 ± 7 ms/mmHg, P = 0.04) and AA distensibility (16.5 ± 6.0 vs. 10.5 ± 3.8 mmHg(-1) × 10(-3), P = 0.02) were greater in females than males. Sex differences in cvBRS were eliminated after controlling for AA distensibility (P = 0.19). There were no sex differences in CS distensibility (5.32 ± 2.3 vs. 4.63 ± 1.3 mmHg(-1) × 10(-3), P = 0.32). The present data demonstrate that AA mechanics are an important contributor to differences in cvBRS.

  10. Clinical Follow-up on Sagittal Fracture at the Temporal Root of the Zygomatic Arch: Does It Need Open Reduction?

    Directory of Open Access Journals (Sweden)

    Ji Seon Cheon

    2013-09-01

    Full Text Available Background The zygoma is a major portion of the midfacial contour. When deformity occursin this area, a reduction should be conducted to correct it. If a sagittal fracture at the temporalroot of the zygomatic arch occurs, this also requires reduction, but it is difficult to approachdue to its anatomical location, and the possibility of fixation is also limited. Thus, the authorsattempted the reduction of sagittal fracture by two- or three-point fixation and the Gilliesapproach without direct manipulation. The preoperative and postoperative results of thepatients were evaluated. Follow-up was performed to establish a treatment guideline.Methods A retrospective study was done with 40 patients who had sagittal fractures at thetemporal root of the zygomatic arch from March 2009 to June 2012. Only two- or three-pointfixation was performed for the accompanying zygomatic-orbital-maxillary fracture. The Gilliesapproach was used for complex fractures of the zygomatic arch, while the temporal root ofthe zygomatic arch was only observed without reduction. Preoperative and postoperativecomputed tomography and X-ray scans were performed to examine the results.Results The result of the paired t-test on preoperative and postoperative bone gap differences,the depression level, and the degree of temporal protrusion showed a marked decrease in themean difference at a 95% confidence interval. The results were acceptable.Conclusions In the treatment of sagittal fractures at the temporal root of the zygomatic arch,it is acceptable to use indirect reduction and non-fixation methods. This leads to a satisfactoryaesthetic and functional outcome.

  11. An Analytical Solution for Lateral Buckling Critical Load Calculation of Leaning-Type Arch Bridge

    Directory of Open Access Journals (Sweden)

    Ai-rong Liu

    2014-01-01

    Full Text Available An analytical solution for lateral buckling critical load of leaning-type arch bridge was presented in this paper. New tangential and radial buckling models of the transverse brace between the main and stable arch ribs are established. Based on the Ritz method, the analytical solution for lateral buckling critical load of the leaning-type arch bridge with different central angles of main arch ribs and leaning arch ribs under different boundary conditions is derived for the first time. Comparison between the analytical results and the FEM calculated results shows that the analytical solution presented in this paper is sufficiently accurate. The parametric analysis results show that the lateral buckling critical load of the arch bridge with fixed boundary conditions is about 1.14 to 1.16 times as large as that of the arch bridge with hinged boundary condition. The lateral buckling critical load increases by approximately 31.5% to 41.2% when stable arch ribs are added, and the critical load increases as the inclined angle of stable arch rib increases. The differences in the center angles of the main arch rib and the stable arch rib have little effect on the lateral buckling critical load.

  12. The Management of Cephalic Arch Stenosis in Arteriovenous Fistulas for Hemodialysis: A Systematic Review

    Energy Technology Data Exchange (ETDEWEB)

    Vasanthamohan, Lakshman, E-mail: lakshman.vasanthamohan@medportal.ca; Gopee-Ramanan, Prasaanthan, E-mail: Prasa.gopee@medportal.ca; Athreya, Sriharsha, E-mail: sathreya@stjoes.ca [McMaster University, Faculty of Health Sciences (Canada)

    2015-10-15

    AimTo conduct a systematic review of management of current cephalic arch stenosis (CAS) and associated outcomes in the context of dysfunctional hemodialysis access.Materials and MethodsPubMed, Web of Science, and Cochrane Library were searched to retrieve literature on the management of CAS. Studies had to focus on management of access stenosis solely in the cephalic arch. Case reports and literature reviews were excluded. Studies were categorized by intervention, and primary and secondary patency data were compiled. Studies were aggregated, and meta-analyses were performed where possible.ResultsNine papers satisfied the aforementioned criteria: five were retrospective studies and four were prospective studies. CAS management strategies have included percutaneous transluminal balloon angioplasty (PTA), peripheral cutting balloons, surgical cephalic vein transpositions, bare stents, and stent grafts. Reporting strategies varied between studies. Meta-analyses showed that results were variable even within studies using the same modality, particularly for PTA.ConclusionNo singular, definitive management strategy exists for CAS. Current studies are limited by being primarily single-center retrospective trials featuring heterogenous patient populations, interventions, and endpoints. Priorities for future studies should include larger randomized trials, more uniform management strategies and endpoints, and a longer duration of follow-up.

  13. The Management of Cephalic Arch Stenosis in Arteriovenous Fistulas for Hemodialysis: A Systematic Review

    International Nuclear Information System (INIS)

    AimTo conduct a systematic review of management of current cephalic arch stenosis (CAS) and associated outcomes in the context of dysfunctional hemodialysis access.Materials and MethodsPubMed, Web of Science, and Cochrane Library were searched to retrieve literature on the management of CAS. Studies had to focus on management of access stenosis solely in the cephalic arch. Case reports and literature reviews were excluded. Studies were categorized by intervention, and primary and secondary patency data were compiled. Studies were aggregated, and meta-analyses were performed where possible.ResultsNine papers satisfied the aforementioned criteria: five were retrospective studies and four were prospective studies. CAS management strategies have included percutaneous transluminal balloon angioplasty (PTA), peripheral cutting balloons, surgical cephalic vein transpositions, bare stents, and stent grafts. Reporting strategies varied between studies. Meta-analyses showed that results were variable even within studies using the same modality, particularly for PTA.ConclusionNo singular, definitive management strategy exists for CAS. Current studies are limited by being primarily single-center retrospective trials featuring heterogenous patient populations, interventions, and endpoints. Priorities for future studies should include larger randomized trials, more uniform management strategies and endpoints, and a longer duration of follow-up

  14. A comparison of dental arch forms in permanent dentition of a young population in Berlin with the forms of the prefabricated archwires according to McLaughlin, Bennett and Trevisi

    OpenAIRE

    Kawasmi, Nadia

    2012-01-01

    The aims of the present study were to determine the frequency distribution of the arch forms manufactured by the company 3M Unitek (OrthoForm I tapered, OrthoForm II square, OrthoForm III ovoid, and OrthoForm LA) in mandibular arches of Caucasians from an orthodontic practice in Berlin and to give a recommendation for reserving archwires in a practice. Furthermore it aims to clarify if there is a relationship between dental arch form and Angle Class or gender and finally to compare the comput...

  15. Suspension of the tongue to the digastric tendon following resection of the anterior mandibular arch for oral cancer prevents postoperative tongue fall and avoids the need for tracheostomy

    Directory of Open Access Journals (Sweden)

    D Pandey

    2012-01-01

    Full Text Available Background: Resection of the anterior arch of the mandible leads to tongue fall and postoperative stridor because of the detachment of tongue musculature from the mandible. In this article, a simple method of tongue suspension is described which would prevent such complications and the need for tracheostomy. Settings and Design: This study was carried out on patients with oral cancer requiring resection of the anterior arch of the mandible as a part of the surgical resection at a tertiary centre. Materials and Methods: This study was performed on 32 patients with oral cancer requiring resection of the anterior arch of the mandible as a part of the surgical resection. Following an appropriate resection of the oral cancer (including the anterior mandibular arch and neck dissection, a silk suture is used to loop the tongue musculature on either side to the intermediate tendon of the digastric muscle. Result: This technique of tongue suspension was used in 32 patients who required resection of the anterior mandibular arch for oral cancer. Prophylactic tracheostomy was not performed. One patient developed stridor at extubation and required temporary tracheostomy. All other patients could be successfully extubated within 12 h of surgery and none experienced postoperative stridor or sleep apnea. One other patient required temporary tracheostomy for pulmonary toilet as he developed aspiration pneumonitis related to nasogastric feed. Conclusion: This simple method of tongue suspension to the digastric tendon prevents postoperative tongue fall and obviates the need for tracheostomy in most instances.

  16. Antenatal evaluation of fetal interrupted aortic arch type B

    Directory of Open Access Journals (Sweden)

    Ali Babacan

    2015-06-01

    Full Text Available Interruption of the aortic arch (IAA is a rare, severe form of congenital heart defect characterized by complete anatomical discontinuity between two adjacent segments of the aortic arch. The data on the features and outcomes of fetal IAA are limited. Three anatomical types have been described according to the site of interruption. The current recommendations for screening on the obstetric fetal anomaly scan include identification of a 4-chamber view, all 4 valves, and the outflow tracts, all of which can appear to be normal to the ultrasonographer in fetuses with conotruncal anomalies. Although the identification of IAA on a prenatal echocardiogram can be challenging, a number of anatomic features can facilitate the diagnosis. We aim to present the features and outcome of a case of IAA type B referred to our centre in the light of literatures.

  17. Super-light pearl-chain arch vaults

    DEFF Research Database (Denmark)

    Hertz, Kristian Dahl; Halding, Philip Skov

    2014-01-01

    are assembled on the erection site by means of post-tensioning and lifted in place in buildings and bridges. The super-light SL-deck element is developed by the company Abeo Ltd and The Technical University of Denmark for plane floor structures in buildings. However, this deck element is designed in such a way...... that it is also applicable as basic elements for super-light pearl-chain vaults. Machines and software have been developed for automatic mass production of the elements, and the first factory has started production in Denmark in 2014 delivering SL-deck elements for a variety of building projects. This means...... that the basic elements have become affordable and arch vaults can now be applied at a very low cost and much cheaper than ever before. The new technology is therefore capable of re-introducing the arch vault in construction. The application of SLdecks means that the advantages of these elements are incorporated...

  18. CREATIVITY METHODS IN TEACHING THE ARCH-DESIGN STUDIO

    OpenAIRE

    EIGBEONAN, Andrew B.

    2013-01-01

    The aim of this paper is to search and find methods of fostering creativity or ideas relating to creativity in teaching the arch-design studio. Teaching creativity through its methods will be making the students grounded in designing with creativity ideas and therefore we can have professionals that design and build with satisfaction, safety and complementary. It means we can have real buildings and places that satisfy our clients, the society and in harmony with the environment. Although the...

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

    Science.gov (United States)

    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

  20. Space maintainer effects on intercanine arch width and length.

    Science.gov (United States)

    Dincer, M; Haydar, S; Unsal, B; Turk, T

    1996-01-01

    In order to investigate the effects of space maintainers in intercanine arch width and length, twenty cases, characterized with the early loss of mandibular primary molars were selected and divided into two groups. The treatment group used removable space maintainers, while the other ten cases served as the control group. The first dental casts of the treatment and control groups were obtained when the primary canines were in the mouth. After the eruption of permanent canines second dental casts were obtained in both groups. Six measurements were made on the dental casts of each patient. No parameter was found to be statistically significant in the treatment group. In the control group the increase in intercanine arch width and perimeter were found to be statistically significant. Also the increase at the buccal and lingual bone measurements were found to be statistically significant. These results showed that space maintainers might cease the increase in intercanine arch width and length during the transition period between the primary and permanent canines.

  1. First and second branchial arch syndromes: multimodality approach

    Energy Technology Data Exchange (ETDEWEB)

    Senggen, Elodie; Laswed, Tarek; Meuwly, Jean-Yves; Maestre, Leonor Alamo; Meuli, Reto; Gudinchet, Francois [University Hospital of Lausanne, Radiology Department, Lausanne (Switzerland); Jaques, Bertrand [University Hospital of Lausanne, Department of Otorhinolaryngology, Lausanne (Switzerland)

    2011-05-15

    First and second branchial arch syndromes (BAS) manifest as combined tissue deficiencies and hypoplasias of the face, external ear, middle ear and maxillary and mandibular arches. They represent the second most common craniofacial malformation after cleft lip and palate. Extended knowledge of the embryology and anatomy of each branchial arch derivative is mandatory for the diagnosis and grading of different BAS lesions and in the follow-up of postoperative patients. In recent years, many new complex surgical approaches and procedures have been designed by maxillofacial surgeons to treat extensive maxillary, mandibular and external and internal ear deformations. The purpose of this review is to evaluate the role of different imaging modalities (orthopantomogram (OPG), lateral and posteroanterior cephalometric radiographs, CT and MRI) in the diagnosis of a wide spectrum of first and second BAS, including hemifacial microsomia, mandibulofacial dysostosis, branchio-oto-renal syndrome, Pierre Robin sequence and Nager acrofacial dysostosis. Additionally, we aim to emphasize the importance of the systematic use of a multimodality imaging approach to facilitate the precise grading of these syndromes, as well as the preoperative planning of different reconstructive surgical procedures and their follow-up during treatment. (orig.)

  2. Modelling autogenous expansion for magnesia concrete in arch dams

    Institute of Scientific and Technical Information of China (English)

    Feng JIN; Guoxin ZHANG; Xiaoqing LUO; Chuhan ZHANG

    2008-01-01

    Magnesia Concrete is a kind of expansive con-crete used in Chinese hydraulic engineering more and more widely. To evaluate the effects of autogenous expan-sion on the stresses of arch dams, a simple model of auto-genous expansion for Magnesia Concrete in dam engineering is presented. This model is based on three assumptions: 1) the total amount of autogenous expan-sion of Magnesia Concrete is related only to the properties of materials and mixing of concrete; 2) the autogenous expansion of Magnesia Concrete is irreversible due to the irreversibility of hydration reaction of Magnesia in the concrete; 3) the autogenous expansion strain rates of Magnesia Concrete bear a relation between temperature and residual Magnesia per unit volume of concrete. The model is verified by some experimental data of autogen-ous expansion of Magnesia Concrete and field-measured data of an arch dam in China. Embedded into finite ele-ment arch dam simulation software, this model is employed to simulate the effects of autogenous expansion of Magnesia Concrete in hydraulic engineering.

  3. Mechanics Evolution Characteristics Analysis of Pressure-arch in Fully-mechanized Mining Field

    Directory of Open Access Journals (Sweden)

    S.R. Wang

    2014-09-01

    Full Text Available Based on a practical engineering, the three-dimension computational model was built using FLAC3D under the fullymechanized mining condition. Considering four variation factors, such as the distance of mining advancing, the strength of the surrounding rock, the speed of mining advancing and the dip angle of the coal seam, the mechanics evolution characteristics of the pressure-arch were analyzed. The result showed that for the horizontal seam, the geometric shape of the pressure-arch varied from flat arch to round arch gradually and the height and thickness of the pressure-arch also increased; the maximum principal stress in the skewback also increased with the working face advancing. With the strength of the surrounding rock from soft to hard, the arch thickness reduced, and the arch loading decreased. To improve the mining speed can do some contributions to the stability of the pressure-arch in the mining field. With the increase of dip angle of the seam, the pressure-arch displayed an asymmetric shape, the vault was tilted and moved to the upward direction. At the same time, the thickness of the pressure-arch increased, and the stress concentration in the skewback tended to be further intensified.

  4. 拱形结构爆炸作用荷载分布规律研究%Research on distribution laws of blast load on arch structure

    Institute of Scientific and Technical Information of China (English)

    洪武; 周健南; 徐迎; 金丰年; 范华林

    2012-01-01

    Distribution laws of blast loads on arch structure induced by underground explosions are studied by numerical method. The results show that the load distribution on arch is mainly effected by the explosion height, the arch span and the angle of monitoring point. The distribution form of load is shape of saddle as a symmetry axis around vault. Load distribution on the arch will be more uniform with the increase of the ratio of explosion distance and span. Conversely, it will be more concentrated. The load distribution on side-wall is mainly effected by the explosion height, the arch span and the side-wall height; and it reduces gradually from wall tip along the wall, finally tends to even distribution. On this basis, a method to calculating load on arch structure with large span is proposed. After calculating the load factor on arch structure, it is found that the load factor around the arch is not a constant value and increases with the increase of arch angle. The minimum value of the factor appears at the vault and it equals to 1.5.%采用数值计算方法对地下高边墙拱形结构在爆炸作用下爆炸荷载的分布规律进行了研究.研究结果表明,拱形部分荷载分布主要受爆高、跨度、观测点角度的影响,荷载分布形式是以拱顶为对称轴的马鞍形.爆高与跨度的比值越大,结构上的荷载分布越均匀,反之,则越集中;边墙部分荷载分布主要受爆高、跨度、边墙高度影响,从墙顶开始沿着墙体逐渐衰减,最终趋于均匀.在此基础上,给出了自由场地下大跨度拱形结构荷载的计算方法,并计算了拱形结构上的荷载系数,发现沿着拱形荷载系数并不是固定值,在拱项最小,近似等于1.5,且随拱角的增加而变大.

  5. The Layout and Simulation of Logarithmic Spiral Double Curved Arch Dam Transverse Joints%The Layout and Simulation of Logarithmic Spiral Double Curved Arch Dam Transverse Joints

    Institute of Scientific and Technical Information of China (English)

    DU Ting-na; DU Qi-lu; HUI Yuan

    2011-01-01

    Because of its good condition with mechanics, logarithmic spiral double curve arch bam has been widely used in the practical engineering. The introduction of a new method in how to divide transverse joint in arch dam will be given and the further research of its calculation has been done. The C++ is used in electronic procedure and the 3D simulation has been finished with AutoCAD, which will provide the object model for computer simulation of the arch dam and the division of finite element mesh. Meanwhile, this method in dividing the transverse joint in arch dam also can be taken as the calculated basis for the design and calculation of arch dam, construction lofting and the calculation of the work amount.

  6. Effects of outlets on cracking risk and integral stability of super-high arch dams.

    Science.gov (United States)

    Lin, Peng; Liu, Hongyuan; Li, Qingbin; Hu, Hang

    2014-01-01

    In this paper, case study on outlet cracking is first conducted for the Goupitan and Xiaowan arch dams. A nonlinear FEM method is then implemented to study effects of the outlets on integral stability of the Xiluodu arch dam under two loading conditions, i.e., normal loading and overloading conditions. On the basis of the case study and the numerical modelling, the outlet cracking mechanism, risk, and corresponding reinforcement measures are discussed. Furthermore, the numerical simulation reveals that (1) under the normal loading conditions, the optimal distribution of the outlets will contribute to the tensile stress release in the local zone of the dam stream surface and decrease the outlet cracking risk during the operation period. (2) Under the overloading conditions, the cracks initiate around the outlets, then propagate along the horizontal direction, and finally coalesce with those in adjacent outlets, where the yield zone of the dam has a shape of butterfly. Throughout this study, a dam outlet cracking risk control and reinforcement principle is proposed to optimize the outlet design, select the appropriate concrete material, strengthen the temperature control during construction period, design reasonable impounding scheme, and repair the cracks according to their classification. PMID:25152907

  7. Aortic arch and intra-/extracranial cerebral arterial atherosclerosis in patients suffering acute ischemic strokes

    Institute of Scientific and Technical Information of China (English)

    郭毅; 姜昕; 陈实; 张少文; 赵宏文; 吴瑛

    2003-01-01

    Objective To determine the distribution of aortic arch and intra/extracranial cerebral arterial atherosclerosis in Chinese patients who had suffered acute ischemic strokes. Methods Eighty-nine patients with acute ischemic strokes were included in this study. Transesophageal echocardiography (TEE) was used to evaluate potential sources of embolisms in the aortic arch and in the heart; duplex ultrasound was used for the carotid artery; and intracranial Doppler (TCD) imaging was used for the middle cerebral artery (MCA), anterior cerebral artery (ACA), posterior cerebral artery (PCA), and basilar artery (BA). An atherosclerotic lesion in the aortic arch was defined as normal (0); mild plaque (1); moderate plaque (2); and protruding plaque or mobile plaque (3). A lesion in the carotid artery was considered a plaque if the maximal carotid plaque thickness was 1.2 mm. TCD results were deemed abnormal if flow velocity was either greater or lower than normal, and, in the case of the MCA, if an asymmetry index above 21% was measured. Results Of the 89 patients, 52 (58.43%) patients showed evidence of aortic arch atherosclerosis (AAA), including 11 (12.36%) patients graded mild, 18 (20.22%) patients graded moderate, and 23 (25.84%) patients graded severe. Of the 23 patients with severe AAA, AAA was determined to be an important potential embolic source in 14 patients. Forty-nine (50.56%) patients had carotid arterial plaques (CAPs). The incidence of carotid plaques was higher among patients with AAA than among patients without AAA (71.15% vs 21.62%, OR=3.291, 95% CI=1.740-6.225, P<0.001). TCD abnormalities affecting the MCA were found in 54 (60.67%) patients. Differences in incidence of TCD abnormalities between patients with AAA and without AAA (69.23% vs 48.65%) were not significant (OR=1.423, 95% CI=0.976-2.076, P=0.05). There was a higher incidence of AAA in older, male patients with a history of diabetes and smoking. Conclusions AAA is an important potential source of

  8. 多种加固方法应用于双曲拱桥主拱圈的提载加固%Reinforcement for Improving Bearing Capacity of A Double Arch Bridge Main Arch by Strengthen Methods

    Institute of Scientific and Technical Information of China (English)

    黄伟; 申波; 薛守宝; 梁影

    2012-01-01

    In this paper, reinforcement for improving the bearing capacity of a double arch bridge is studied. Based on the test results of a double-arched bridge of Anshun in Guizhou province, the strengthening program of the main arch is proposed. At the section of arch feet, the moment bearing capacity is improved by enlarged upper edge concrete and lower edge concrete of the section, the section is changed to box section. At the other section of the arch, the negative moment bearing capacity is improved by enlarged upper edge concrete of the section, and the positive moment bearing capacity is improved. For the deficiencies of the positive moment bearing capacity, the bonding steel plate is recommended at the arch rib of the other section. The results show that the reinforcement methods can improve load level of the bridge effectively. The construction of the bridge is convenient and can satisfy the design goals.%针对双曲拱桥的提载加固,基于贵州省安顺市木浪河大桥的检测结果,提出了在主拱圈的拱脚上缘增大截面、下缘增大截面改造为箱形断面,以提高拱脚抵抗负弯矩、正弯矩的承载能力;对其它截面采用拱背增大截面以提高抵抗负弯矩的承载能力,相应也提高了抵抗正弯矩的承载能力;对正弯矩承载能力不足的截面,采用粘贴钢板的加固方法.结果表明:采用这种提载加固的设计方法,达到了提高荷载等级的目的,同时方便施工,便于达到加固效果.

  9. Numerical investigation on thermal conditions for a tee junction of LMFBR coolant pipes. 5. Investigations on flow conditions for arched-vortex generation

    Energy Technology Data Exchange (ETDEWEB)

    Murakami, Satoshi [Customer System Co. Ltd., Tokai, Ibaraki (Japan); Muramatsu, Toshiharu [Japan Nuclear Cycle Development Inst., Oarai, Ibaraki (Japan). Oarai Engineering Center

    2001-04-01

    A fundamental experiment, the aim of which is to quantify turbulent mixing characteristics, was carried out at Hiroshima University in the framework of a cooperative study with Japan Nuclear Cycle Development Institute (JNC). Turbulent mixing analyses for the fundamental experiment were carried out using a direct numerical simulation code DINUS-3 at JNC. >From the analyses, the following results have been obtained: (1) It was confirmed that the numerical analysis is applicable to the evaluation of the three flow patterns observed in the experiment: an adhesion flow, a deflection flow and an impinging flow. (2) In the deflection flow analysis, arched-vortex characteristics with lower frequency fluctuations agreed well with the experimental results. (3) Frequency of arched-vortex transportation depended on the Reynolds number. The frequency of arched-vortex was increased with increasing the Reynolds number under the condition of the constant velocity ratio between coolant pipes. (author)

  10. Calculation Model of Equivalent Strength for Induced Crack Based on Double-K Fracture Theory and Its Optimizing Setting in RCC Arch Dam

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xiaogang; SONG Yupu; WU Zhimin

    2005-01-01

    By means of fracture testing on roller-compacted concrete (RCC) three-point bending beams with two different specimen sizes, the P-CMOD complete curve for RCC was gained. Furthermore, by applying double-K fracture theory, KiniⅠC,KunⅠC, as well as the critical effective crack length and the critical crack tip opening displacement, were evaluated. Based on the double-K fracture parameters above, the calculation model of equivalent strength for induced crack was established, thus the calculation method on its initiation, stable propagation and unstable fracture was ascertained. Moreover, the finite element simulation analysis of stress field in ShaPai arch dam and the on-site observational splaying points of induced crack at different altitudes validated the reliability of the model. Finally, crack inducer's optimal setting in RCC arch dam was studied. It improves the design level of induced crack in RCC arch dam and satisfies the necessity of engineering practice.

  11. Initial arch wires for alignment of crooked teeth with fixed orthodontic braces.

    LENUS (Irish Health Repository)

    Wang, Yan

    2010-01-01

    The initial arch wire is the first arch wire to be inserted into the fixed appliance at the beginning of orthodontic treatment and is used mainly for correcting crowding and rotations of teeth. With a number of orthodontic arch wires available for initial tooth alignment, it is important to understand which wire is most efficient, as well as which wires cause the least amount of root resorption and pain during the initial aligning stage of treatment.

  12. Study on the Relationship between the Features of the City and the Timber Arch Lounge Bridge in Eastern Fujian as the Background of West Coast of the Taiwan Straits%海西背景下闽东木拱廊桥与城市特色研究

    Institute of Scientific and Technical Information of China (English)

    赵兵; 郑立文; 何细树; 宋云珍

    2012-01-01

    Timber arch lounge bridge mainly located in Eastern Fujian, the Eastern Fujian oities with abundant resource* and cultural traditions in Timber arch lounge bridge need to fully exploit the relationship between the character and resources of the cities. In this paper, for local conditions and regional characteristics, we discussed the relationship between timber arch lounge bridge and the features of the city, and proposed to build a Featured Cities with Timber arch lounge bridge.%福建闽东地区是我国木拱廊桥的主要分布地.在海西发展背景下,有着丰富廊桥资源和悠久廊桥文化的闽东城市需要充分发掘城市资源与城市特色之间的关系.本文就这一问题,针对闽东地区的实际情况和地域特色,论述了闽东木拱廊桥与城市特色的关系,提出建设具有木拱廊桥特色城市的建议.

  13. NUMERICAL STUDY OF STRESS-STRAIN STATE OF A FRAGMENT OF A SOIL ARCH IN THE FRAMEWORK OF FULFILLMENT OF COMPLEX OF WORKS ON ENHANCEMENT OF THE SUBTERRANEAN CHURCH OF THE NATIVITY OF THE SVYATO-USPENSKOY KYIV-PECHERSK LAVRA

    Directory of Open Access Journals (Sweden)

    Vabishchevych М.О.

    2015-12-01

    Full Text Available The paper considers the investigation of the features of stress-strain state of the structure with heterogeneous physical and mechanical properties on the example of the finite element calculation model of soil arch, which is reinforced by composite reinforcing cage.

  14. [The form of the dental arch according to the Tweed-Merrifield philosophy: individualization and attempt at standardization].

    Science.gov (United States)

    Amm, E W; Bou-Serhal, J P

    2003-12-01

    A literature review reveals that changes from the initial arch form lead to a proportionate amount of subsequent relapse and that there is great variation among human arch forms. A persistent search for the ideal arch form is still going on. Many authors presented different techniques for its individualization. A new software ("Arch form generator") was developed to create the arch form following the Tweed-Merrifield concepts. The form and dimensions of 169 mandibular arches were evaluated along with Angle classification and facial type as variables. The reliability of the Ricketts pentamorphic arch forms was questioned and a new arch guide was developed as part of a trial for standardization. The Class III cases showed greater width and smaller cuspid depth when compared to the Class I and Class II cases. The hypodivergent cases showed greater width when compared to the hyperdivergent and normodivergent cases. There is no characteristic form for the human dental arch. PMID:15301362

  15. The effect of medial arch support over the plantar pressure and triceps surae muscle strength after prolonged standing

    Directory of Open Access Journals (Sweden)

    Hindun Saadah

    2015-11-01

    Full Text Available Background: The activity with prolonged standing position is one of the causes of abnormalities in the lower leg and foot. The aim of this study is to discover the effect of medial arch support over the distribution of plantar pressure when standing and walking.Methods: This was an experimental study with pre- and post-design the strength of triceps surae muscle after prolonged standing, was also evaluated in an experimental study with pre- and post-design. Variables of plantar pressure measurement are the contact area and pressure peak were measured by using the Mat-scan tool. The measurement of the triceps surae muscle strength was done with a hand-held dynamometer, before and after using the medial arch support. Measurement was performed before and after working with prolonged standing position which took place about seven hours using the medial arch support inserted in the shoes. Data was analyzed using paired T-test.Results: There was a significant difference of peak pressure between standing (p = 0.041 and walking (p = 0.001. Whereas the contact area showed a significant decrease in the width of the contact area when standing (104.12 ± 12.42 vs 99.08 ± 10.21 p = 0.023. Whereas, the triceps surae muscle strength pre- and post-standing prolonged did not indicate a significant difference.Conclusion: There was decrease in peak pressure when standing and walking and decrease in contact area when standing on plantar after used of the medial arch support after prolonged standing.

  16. Correlation of atherosclerotic changes in peripheral arteries with pathological involvement of aortic arch in coronary bypass patients

    Directory of Open Access Journals (Sweden)

    Eshraghi N

    2010-10-01

    Full Text Available "nBackground: A correlation between coronary artery disease (CAD and atherosclerosis of peripheral arteries and the determination of noninvasive indexes for its existence and extent have been sought by many researchers. Some studies report that the intima-media thickness (IMT of peripheral arteries could play this role. This study evaluated the correlation between the IMTs of common carotid and common femoral arteries and the degree of atherosclerosis in aortic arch and to evaluate the severity of CAD in candidates of coronary artery bypass grafting (CABG."n "nMethods: In a cross-sectional analytic-descriptive study, The severity of CAD, the grade of atherosclerosis of the aortic arch, and the IMTs of the common carotid and common femoral arteries were determined."n "nResults: There was a significant weak positive correlation between the IMT of common carotid artery (ρ = 0.193, p = 0.039 and common femoral artery (ρ = 0.206, p = 0.028 with the number of involved carotid vessels; the mean of these two parameters was not significantly different between the three CAD groups. There was not any significant relation between the IMTs of common carotid and common femoral arteries with the severity of atherosclerosis in the aortic arch too. There was not any significant relation between the presences of atherosclerotic plaque in the common carotid or the common femoral arteries with the severity of CAD. The severe atherosclerosis of the aortic arch was significantly higher in patients with three vessel disease."n "nConclusion: According to our results, the IMTs of common carotid and/or common femoral arteries may increase with the severity of CAD; however, these parameters are not a surrogate for predicting the CAD severity.

  17. KD loop for increasing arch perimeter in cleft and noncleft cases.

    Science.gov (United States)

    Dholakia, Kartik D; Bhat, Shweta R

    2012-01-01

    One of the many indications for dental arch expansion in treating malocclusion is to achieve arch compatibility, especially in surgical cases with severe Bolton discrepancies or collapsed arches due to congenitally missing anterior teeth. These cases usually require expansion in both the sagittal and transverse plane to achieve normal arch compatibility. Arch compatibility can be achieved by either dentoalveolar or skeletal expansion or both. Orthodontically, dentoalveolar expansion can be achieved by means of expanded arch form, vertical loops, or an added assembly such as a quad helix or Ni-Ti expander from the palatal or lingual aspect of the arch. However, these modalities normally provide expansion along transverse plane. If any expansion along sagittal plane is required, then additional appliances such as TransForce or modifications in the appliance system (eg, a quad helix with extension on anterior teeth) are necessary. Vertical loops do overcome these drawbacks to a certain extent; however, at the expense of generating moments during preactivation, which may lead to tipping of segments adjacent to the loop and precludes its use for larger changes of arch dimension. This article describes a new loop design--the KD loop--that increases the arch perimeter by sagittal and transverse expansion without generating significant moments along vertical plane. PMID:22567644

  18. Congenital aortic arch anomalies: diagnosis using contrast enhanced magnetic resonance angiography

    Institute of Scientific and Technical Information of China (English)

    ZHU Ming; ZHONG Yu-min; LI Yu-hua; SUN Ai-min; JIN Biao

    2005-01-01

    @@ Congenital aortic arch anomalies occur most commonly in children. The disease can be classified into three types: ① obstructive congenital abnormalities, including coarctation of aorta (CoA) and interruption of aortic arch (IAA); ② non-obstructive congenital abnormalities, including double aortic arch and others; ③ congenital shunt abnormalities, including different types of patent ductus arteriosus (PDA). Management of patients with congenital aortic arch anomalies relies on imaging. Routine imaging modalities, such as conventional X-ray plain film and transthoracic echocardiography (TTE), have been recently complemented by magnetic resonance imaging (MRI).

  19. Ennis Franciscan Friary, eastern tomb niche, north nave wall, jamb and arch moulding

    OpenAIRE

    O'Donovan, Danielle

    2005-01-01

    Jamb and arch of tomb niche. From intrados moulding comprises: ogee, quadrant. Similar tomb niches can be found at Quin, Adare Franciscan, Adare Augustinian, Askeaton, Lislaughtin, Abbeydorney, Kilconnell.

  20. Track-Bridge Longitudinal Interaction of Continuous Welded Rails on Arch Bridge

    Directory of Open Access Journals (Sweden)

    Rong Chen

    2013-01-01

    Full Text Available Taking arch bridges, including deck, half-through, and through arch bridges (short for DAB, HTAB, and TAB as examples, mechanics analysis models of longitudinal interaction between continuously welded rails (short for CWRs and arch bridges are established. Based on the finite element method (FEM, the longitudinal interaction calculation software of CWR on arch bridges has been developed. Focusing on an HTAB, the tension, compression, and deflection conditions are calculated and analyzed. The results show that the mechanics analysis models of three types of arch bridges can truly reflect the real state of the structure; the calculation software can be used for systematic research of the CWR on arch bridge; as for HTAB, temperature difference of arch rib has a small effect on rail tension/compression, and arch bridge can be simplified as a continuous beam for rail tension/compression additional force calculation; in calculation of deflection conditions of HTAB, it is suggested that train loads are arranged on half span and full span and take the direction of load entering bridge into account. Additionally, the deflection additional force variation of CFST basket handle arch bridge is different from that of ordinary bridge.

  1. Dental arch Transversal characteristics in boys and girls with orthognathic bite: head shape and face type dependence

    Directory of Open Access Journals (Sweden)

    Gunas Іgor

    2015-03-01

    Full Text Available In this work, we describe the boundary percentile scope values of transversal characteristics of the dental arch of boys and girls of Podillia, with diagnosed orthognathic bite. The study group consists of individuals with different forms of head and face. Our findings are that, in girls, unlike boys, set differences exist in the transversal dimensions of the upper and lower jaw, both in the distribution of the shape of the head, and the type of face. In boys with different head shape, larger values of transversal size of dental arch are evidenced when contrasted with the corresponding groups of girls, regarding the maxilla in 46.7% of all cases and the mandible in 22.2% of all cases, as well as with different types of faces in 66.7% of cases regarding the maxilla and 55.6% in the mandible.

  2. a Method for Virtual Anastylosis: the Case of the Arch of Titus at the Circus Maximus in Rome

    Science.gov (United States)

    Canciani, M.; Falcolini, C.; Buonfiglio, M.; Pergola, S.; Saccone, M.; Mammì, B.; Romito, G.

    2013-07-01

    This paper is the first report about the development of a methodology for the virtual Anastylosis of elements belonging to an archaeological site, based on the 3d modeling of fragments. This research is the result of the cooperation between Università Roma Tre, Dipartimento di Architettura and Sovrintendenza Capitolina ai Beni Culturali; several 3D survey, modeling, information systems and archaeology experts were involved. The purpose of the research was to study the complex and stratified site of the Arch of Titus at the Circus Maximus aiming, first of all, at completing the existing traditional graphic documentation using cataloguing and survey innovative methodologies, and, secondly, at supporting new proposals for the reconstruction and Anastylosis of the Arch itself. This tested methodology whose fundamental element is the three-dimensional textured model of each fragment, can also be used in other sites and contexts.

  3. Characterization of transient groundwater flow through a high arch dam foundation during reservoir impounding

    Directory of Open Access Journals (Sweden)

    Yifeng Chen

    2016-08-01

    Full Text Available Even though a large number of large-scale arch dams with height larger than 200 m have been built in the world, the transient groundwater flow behaviors and the seepage control effects in the dam foundations under difficult geological conditions are rarely reported. This paper presents a case study on the transient groundwater flow behaviors in the rock foundation of Jinping I double-curvature arch dam, the world's highest dam of this type to date that has been completed. Taking into account the geological settings at the site, an inverse modeling technique utilizing the time series measurements of both hydraulic head and discharge was adopted to back-calculate the permeability of the foundation rocks, which effectively improves the uniqueness and reliability of the inverse modeling results. The transient seepage flow in the dam foundation during the reservoir impounding was then modeled with a parabolic variational inequality (PVI method. The distribution of pore water pressure, the amount of leakage, and the performance of the seepage control system in the dam foundation during the entire impounding process were finally illustrated with the numerical results.

  4. Structural framework and Mesozoic Cenozoic evolution of Ponta Grossa Arch, Paraná Basin, southern Brazil

    Science.gov (United States)

    Strugale, Michael; Rostirolla, Sidnei Pires; Mancini, Fernando; Portela Filho, Carlos Vieira; Ferreira, Francisco José Fonseca; de Freitas, Rafael Corrêa

    2007-09-01

    The integration of structural analyses of outcrops, aerial photographs, satellite images, aeromagnetometric data, and digital terrain models can establish the structural framework and paleostress trends related to the evolution of Ponta Grossa Arch, one of the most important structures of the Paraná Basin in southern Brazil. In the study area, the central-northern region of Paraná State, Brazil, the arch crosses outcropping areas of the Pirambóia, Botucatu, and Serra Geral Formations (São Bento Group, Mesozoic). The Pirambóia and Botucatu Formations are composed of quartz sandstones and subordinated siltstones. The Serra Geral Formation comprises tholeiitic basalt lava flows and associated intrusive rocks. Descriptive and kinematic structural analyses reveal the imprint of two brittle deformation phases: D1, controlled by the activation of an extensional system of regional faults that represent a progressive deformation that generated discontinuous brittle structures and dike swarm emplacement along a NW-SE trend, and D2, which was controlled by a strike-slip (transtensional) deformation system, probably of Late Cretaceous-Tertiary age, responsible for important fault reactivation along dykes and deformation bands in sandstones.

  5. Analysis of foundation sliding of an arch dam considering the hydromechanical behavior

    Institute of Scientific and Technical Information of China (English)

    Maria; Luísa; Braga; FARINHA; José; Vieira; de; LEMOS; Emanuel; MARANHA; DAS; NEVES

    2012-01-01

    This paper presents the application of a methodology which can be used to assess arch dam foundation stability,using the discrete element method (DEM) and the code 3DEC.A global three-dimensional model of a dam foundation was developed,in which some discontinuities were simulated and both the grout and drainage curtains were represented.The model,calibrated taking into account recorded data,was used to carry out nonlinear mechanical analysis.The same model was employed to perform a hydraulic analysis,based on equivalent continuum concepts,which allowed the water pressure pattern within the foundation to be obtained.These water pressures were applied on discontinuities involved in the possible sliding mechanism along the dam/foundation interface,and the safety of the dam/foundation system was evaluated using a process of reduction of strength characteristics,with the aim of calculating the minimum safety factors that ensure stability.Results were compared with those obtained with the usual bi-linear uplift pressure distribution at the base of the dam,commonly used in concrete dam design.The relevance of carrying out hydraulic analysis in arch dam foundation failure studies is highlighted.

  6. Hypoxic conditions alter developing branchial arch-derived structures in zebrafish

    Directory of Open Access Journals (Sweden)

    Trish E Parsons

    2014-08-01

    Full Text Available Background: Previous epidemiological findings have implicated hypoxia as a risk factor for craniofacial defects including cleft lip, microtia and branchial arch anomalies. This study tests the hypothesis that hypoxic exposure results in craniofacial shape variation in a zebrafish model. Methods: Three sets of zebrafish embryos were raised in uniform conditions with the exception of dissolved oxygen level.  At 24 hours past fertilization (hpf embryos were placed in hypoxic conditions (70% or 50% dissolved oxygen tank water and compared to unexposed control embryos.  After 24 hours of exposure to hypoxia, the embryos were incubated under normoxia.  Larvae were collected at 5 days post fertilization (dpf and stained for cartilage. Images were taken of each specimen and subsequently landmarked to capture viscerocranial morphology.  A geometric morphometric analysis was performed to compare shape variation across groups. Results: The mean branchial arch shape of each exposure group was significantly different from controls (p<0.001.  Principal components analysis revealed a clear separation of the three groups, with controls at one end of the shape spectrum, the 50% hypoxia group at the other end, and the 70% hypoxia group spanning the variation in between. Conclusions: This experiment shows that hypoxia exposure at 24hpf is capable of affecting craniofacial shape in a dose-dependent manner.  These results may have implications not only for high altitude fetal health, but other environments, behaviors and genes that affect fetal oxygen delivery.

  7. Spectropolarimetric observations of an arch filament system with the GREGOR solar telescope

    CERN Document Server

    Balthasar, H; Manrique, S J González; Kuckein, C; Kavka, J; Kučera, A; Schwartz, P; Vašková, R; Berkefeld, T; Vera, M Collados; Denker, C; Feller, A; Hofmann, A; Lagg, A; Nicklas, H; Suárez, D Orozco; Yabar, A Pastor; Rezaei, R; Schlichenmaier, R; Schmidt, D; Schmidt, W; Sigwarth, M; Sobotka, M; Solanki, S K; Soltau, D; Staude, J; Strassmeier, K G; Volkmer, R; von der Lühe, O; Waldmann, T

    2016-01-01

    Arch filament systems occur in active sunspot groups, where a fibril structure connects areas of opposite magnetic polarity, in contrast to active region filaments that follow the polarity inversion line. We used the GREGOR Infrared Spectrograph (GRIS) to obtain the full Stokes vector in the spectral lines Si I 1082.7 nm, He I 1083.0 nm, and Ca I 1083.9 nm. We focus on the near-infrared calcium line to investigate the photospheric magnetic field and velocities, and use the line core intensities and velocities of the helium line to study the chromospheric plasma. The individual fibrils of the arch filament system connect the sunspot with patches of magnetic polarity opposite to that of the spot. These patches do not necessarily coincide with pores, where the magnetic field is strongest. Instead, areas are preferred not far from the polarity inversion line. These areas exhibit photospheric downflows of moderate velocity, but significantly higher downflows of up to 30 km/s in the chromospheric helium line. Our f...

  8. Key parameters for single-input earthquake analysis of arch dams

    Energy Technology Data Exchange (ETDEWEB)

    Proulx, J.; Ayala-Paredes, C. [Sherbrooke Univ., PQ (Canada). Dept. of Civil Engineering

    2010-07-01

    An adequate representation of a dam, its water reservoir and its foundation substructure is needed in modeling the earthquake response of concrete dams. Advanced three-dimensional finite element programs include sophisticated models to account for dam-reservoir-foundation interaction. The calibration of such programs and of their key parameters is best achieved by comparing the computed responses to recorded data obtained from on-site investigation or during actual earthquakes. This paper discussed the influence of the modeling parameters for the earthquake analysis of arch dams using single-input motions obtained from recorded earthquake data. The computed accelerations were compared to recordings of moderate earthquakes using three-dimensional numerical models with properties extracted from on-site dynamic test results for a large arch dam in Switzerland. The paper discussed model parameters for the dam, including mesh size; stiffness; damping; and foundation (damping). Several other important parameters related to the reservoir that were presented in a previous study were also briefly summarized. These parameters included geometry; water level; and damping by wave propagation and absorption. It was concluded that although the computation of a foundation impedance matrix could be time consuming, especially for larger models, the use of a finer, more complex mesh is necessary to predict the response in terms of amplitude and frequency content. 10 refs., 1 tab., 7 figs.

  9. Technical and Clinical Success and Long-Term Durability of Endovascular Treatment for Atherosclerotic Aortic Arch Branch Origin Obstruction : Evaluation of 144 Procedures

    NARCIS (Netherlands)

    van de Weijer, M. A. J.; Vonken, E. J. P. A.; de Vries, J-P. P. M.; Moll, F. L.; Vos, J. A.; de Borst, G. J.

    2015-01-01

    Objectives: Endovascular treatment of atherosclerotic obstruction of aortic arch branch origins (AABO) has largely replaced open surgery, but long-term outcome data are lacking. This study evaluated mid-term and long-term results of these procedures. Design: Retrospective cohort study. Materials and

  10. Calculation of Soil Arch Effect in View of Gravity Stress Field%考虑土体自重应力场的拱效计算方法

    Institute of Scientific and Technical Information of China (English)

    杨雪强; 刘勇健; 吉小明

    2016-01-01

    抗滑桩是用于加固边坡,防止边坡滑移失稳的主要措施,土拱体易在桩间形成。本文将桩间土拱简化为水平拱,并假定处于平面应变状态,在考虑土体自重应力场前提下,对桩侧摩阻力为拱座的拱体计算方法进行了研究,揭示了土体的自重应力场对桩土拱体的量化影响。研究结果表明:自重应力场的存在对桩间土拱效应起着明显的加强作用,不考虑土体的自重应力场,也就是把土体看成是无重介质,进行桩土拱体模式的设计过于安全。%Anti-slide piles are a main measure to reinforce slope for slope stability engineering , in which soil arch is easily formed between piles .Soil arch supported by adjacent piles is assumed to be horizontal and usually kept in plane strain status in vertical direction .It studies the calculating method of the soil arch supported by side surface friction of piles , which is combined with soil mass gravity .Then the influ-ence of the soil gravity on arch bodies is further investigated in the view of quantity calculation .The re-search results show that the arch body in soil mass if considered to be weightless ,is very safe for design purpose , because the gravity stress of soil mass has an important strengthening effect on the soil arch bodies formed between adjacent piles .

  11. Injuries and Footwear (Part 1): Athletic Shoe History and Injuries in Relation to Foot Arch Height and Training in Boots.

    Science.gov (United States)

    Knapik, Joseph J; Pope, Rodney; Orr, Robin; Grier, Tyson

    2015-01-01

    This article traces the history of the athletic shoe, examines whether selecting running shoes based on foot arch height influences injuries, and examines historical data on injury rates when physical training (PT) is performed in boots versus running shoes. In the 1980s and into the 2000s, running shoe companies were advertising specialized shoes with "motion control," "stability," and "cushioning," designed for individuals with low, normal, and high arches, respectively. Despite marketing claims that these shoes would reduce injury rates, coordinated studies in Army, Air Force, and Marine Corps basic training showed that assigning or selecting shoes on this basis had no effect on injury rates. Consistent with this finding, biomechanical studies have shown that the relationships between arch height, foot joint mobility, and rear-foot motion are complex, variable, and frequently not as strong as often assumed. In 1982, the US Army switched from PT in boots to PT in running shoes because of the belief that boots were causing injuries and that running shoes would reduce injury rates. However, a historical comparison of injury rates before and after the switch to running shoes showed virtually no difference in injury risk between the two periods. It is not clear at this point if the type of footwear effects injury incidence.

  12. Deformation Monitoring of Geomechanical Model Test and Its Application in Overall Stability Analysis of a High Arch Dam

    Directory of Open Access Journals (Sweden)

    Baoquan Yang

    2015-01-01

    Full Text Available Geomechanical model testing is an important method for studying the overall stability of high arch dams. The main task of a geomechanical model test is deformation monitoring. Currently, many types of deformation instruments are used for deformation monitoring of dam models, which provide valuable information on the deformation characteristics of the prototype dams. However, further investigation is required for assessing the overall stability of high arch dams through analyzing deformation monitoring data. First, a relationship for assessing the stability of dams is established based on the comprehensive model test method. Second, a stability evaluation system is presented based on the deformation monitoring data, together with the relationships between the deformation and overloading coefficient. Finally, the comprehensive model test method is applied to study the overall stability of the Jinping-I high arch dam. A three-dimensional destructive test of the geomechanical model dam is conducted under reinforced foundation conditions. The deformation characteristics and failure mechanisms of the dam abutments and foundation were investigated. The test results indicate that the stability safety factors of the dam abutments and foundation range from 5.2 to 6.0. These research results provide an important scientific insight into the design, construction, and operation stages of this project.

  13. Two ARCH Models and Their Limitations as Diffusion Processes

    Institute of Scientific and Technical Information of China (English)

    杨海波; 叶俊

    2002-01-01

    Two typical ARCH models: the ASDARCH model and the APARCH model are analyzed. Let Yk and σ2k denote the log returns and the volatility. When the time interval h goes to zero, (Yk,σ2k), as a discrete time Markov chain system, weakly converges to a continuous time diffusion process. The continuous time approximation of the ASDARCH model is done using two different methods. With some transformation, these two results are equivalent to high frequency data. The continuous time approximation of the APARCH model is obtained by a different procedure.

  14. On monolithic stability and reinforcement analysis of high arch dams

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Monolithic stability safety and reinforcement based on monolithic stability are very important for arch dam design.In this paper,the issue is addressed based on deformation reinforcement theory.In this approach,plastic complementary energy norm can be taken as safety Index for monolithic stability.According to deformation reinforcement theory,the areas where unbalanced force exists require reinforcement,and the required reinforcement forces are just the unbalanced forces with opposite direction.Results show that areas with unbalanced force mainly concentrate in dam-toes,dam-heels and faults.

  15. Estudo do relacionamento ântero-posterior entre os arcos dentários decíduos, de crianças nipo-brasileiras, dos dois aos seis anos de idade Study of the anteroposterior relationship between deciduous dental arches of Japanese-Brazilian children, from 2 to 6 years of age

    Directory of Open Access Journals (Sweden)

    Dirce Yamada Kataoka

    2006-10-01

    Full Text Available OBJETIVO: verificar as prevalências dos diferentes tipos de relacionamentos ântero-posteriores entre os arcos dentários decíduos, bem como o possível dimorfismo sexual, em crianças nipo-brasileiras na faixa etária dos dois aos seis anos de idade. METODOLOGIA: foram avaliadas por inspeção visual 310 crianças nipo-brasileiras, matriculadas em 19 escolas do estado de São Paulo, sendo 154 do gênero masculino e 156 do feminino. Os resultados foram submetidos ao teste do qui-quadrado e revelaram ausência de dimorfismo sexual para a maioria dos relacionamentos analisados, permitindo apresentar os resultados conjuntamente para ambos os gêneros. RESULTADOS: as prevalências dos relacionamentos entre os segundos molares decíduos foram: 47,4% para o degrau mesial, 41,3% para o plano terminal reto, 5,5% para o degrau distal e 5,8% para os casos com assimetrias. Para os relacionamentos entre os caninos decíduos, conforme Foster e Hamilton, constataram-se prevalências de 77,4% para a Classe 1, 6,8% para a Classe 2, 6,8% para a Classe 3 e 9% para as relações assimétricas. Apenas a Classe 2 apresentou dimorfismo sexual, sendo de 3,9% para o feminino e de 9,7% para o masculino. Quanto à sobressaliência verificaram-se prevalências de 71,3% para a normal, 14,2% para a aumentada, 7,4% para a mordida cruzada anterior e 7,1% para a mordida topo-a-topo. RESULTADOS: concluiu-se que a maioria das crianças nipo-brasileiras avaliadas neste estudo, apresentaram um relacionamento ântero-posterior normal entre os arcos decíduos, merecendo atenção uma ligeira tendência para o desenvolvimento da Classe 3.AIM: the purpose of this cross-sectional study was to verify the prevalences of different types of anteroposterior relationships between deciduous dental arches and its possible sexual dimorphism, in Japanese-Brazilian children from 2 to 6 years of age. METHODS: a total of 310 Japanese-Brazilian children from 19 schools in São Paulo, Brazil

  16. A hybrid layerwise and differential quadrature method for in-plane free vibration of laminated thick circular arches

    Science.gov (United States)

    Malekzadeh, P.; Setoodeh, A. R.; Barmshouri, E.

    2008-08-01

    An accurate and efficient solution procedure based on the two-dimensional elasticity theory for free vibration of arbitrary laminated thick circular deep arches with some combinations of classical boundary conditions is introduced. In order to accurately represent the variation of strain across the thickness, the layerwise theory is used to approximate the displacement components in the radial direction. Employing Hamilton's principle, the discretized form of the equations of motion and the related boundary conditions in the radial direction are obtained. The resulting governing equations are then discretized using the differential quadrature method (DQM). After performing the convergence studies, new results for laminated arches with different set of boundary conditions are developed. Additionally, different values of the arch parameters such as opening angle, thickness-to-length and orthotropy ratios are considered. In all cases, comparisons with the results obtained using the finite element software 'ABAQUS' and also with those of the first- and higher-order shear deformation theories available in the literature are performed. Close agreements, especially with those of ABAQUS, are achieved.

  17. The arches of the Sanctuary of Loyola. The relationship between the Roman project and Spanish building techniques

    Directory of Open Access Journals (Sweden)

    Iacopo Benincampi

    2015-12-01

    Full Text Available The ascent to the throne of Spain in 1714 by Philip V of Bourbon ended the War of the Spanish Succession, and opened a new period of peace and prosperity that is reflected mainly in the building sites sponsored by the Crown, including also the factory of the Sanctuary of Loyola, which restarted the construction under the leadership of Sebastian Lecuna, who was in charge of raising the circular church. However, the complexity of the project, edited by Carlo Fontana and sent from Rome in 1686, and the changes already made in the plant imposed a careful preliminary reflection which resulted in 1719 in a consultation which was attended by the former director of the factory, Martin de Zaldua, the theoretical Benedictine Pedro Martinez de Cardeña and the Salamanca Cathedral master mayor Joaquin de Churriguera. The masters were contacted to express their opinion about the construction of the vaults of the nave ring, the decoration and especially on the most suitable form to be assigned to the arches of the church, a subject of great interest cause of their uniqueness and complexity. In this sense, the loss of the original drawings do not allow a proper understanding neither of the proposals submitted or the final solution adopted but, nevertheless, a careful study of archival records and the reconstruction of the stereotomic geometry underlies these arches now has led to new contributions, which are useful to a greater general understanding of the factory. Keywords: Loyola, Stereotomy, Carlo Fontana, Sebastian Lecuna, arches

  18. Analysis of Stability of Gaixia Arch Dam Abutment%盖下拱坝坝肩稳定分析

    Institute of Scientific and Technical Information of China (English)

    房巍; 刘晓青

    2011-01-01

    Taking Gaixia arch dam as the object of the research and combining finite elements and rigid limit equilibrium method to study the stability of Gaixia arch dam abutment in static and dynamic conditions, the anti-slide safety factor of the abutment is obtained. The results satisfy the specification; it is shown that the Gaixia arch dam abutment is safe. The results can be taken as reference for practical projects.%以盖下拱坝为研究对象,结合有限元和刚体极限平衡法,分析了盖下拱坝坝肩岩体在静、动力条件下的稳定性,得到坝肩岩体的抗剪安全系数.所得结果满足规范要求,说明盖下拱坝坝肩是稳定的.研究成果为实际工程提供了参考依据.

  19. archAR: an archaeological augmented reality experience

    Science.gov (United States)

    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.

  20. Micron narrowband adaptive optics imaging in the arches cluster

    CERN Document Server

    Blum, R D; Pasquali, A; Heydari-Malayeri, M; Conti, P S; Schmutz, W

    2001-01-01

    Canada-France-Hawaii-Telescope adaptive optics bonnette images through narrow-band filters in the $K-$band are presented for the Arches cluster. Continuum fluxes, line fluxes, and equivalent widths are derived from high angular resolution images, some near diffraction limited, for the well known massive stars in the Arches cluster. Images were obtained in the lines of \\ion{He}{1} 2.06 \\mic, \\ion{H}{1} Br$\\gamma$ (2.17 \\mic), and \\ion{He}{2} 2.19 \\mic as well as continuum positions at 2.03 \\mic, 2.14 \\mic, and 2.26 \\mic. In addition, fluxes are presented for \\ion{H}{1} P$\\alpha$ (1.87 \\mic) and a nearby continuum position (1.90 \\mic) from Hubble Space Telescope archival data. The 2 \\mic and P$\\alpha$ data reveal two new emission-line stars and three fainter candidate emission-line objects. Indications for a spectral change of one object between earlier observations in 1992/1993 and our data from 1999 are found. The ratio of \\ion{He}{2} 2.19 \\mic to Br$\\gamma$ emission exhibits a narrow distribution among the s...

  1. Behaviour of Steel Arch Stabilized by a Textile Membrane

    Science.gov (United States)

    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.

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

    Science.gov (United States)

    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.

  3. Deployment Accuracy of the Conformable GORE® TAG® Thoracic Endoprosthesis in the Treatment of Zones 2 and 3 Aortic Arch Aneurysms Compared with the Previous TAG®

    OpenAIRE

    Ito, Eisaku; Kanaoka, Yuji; Maeda, Koji; Ohta, Hiroki; ISHIDA, ATSUSHI; Ohki, Takao

    2015-01-01

    Purposes: When placing stent grafts, deployment accuracy and birdbeaking due to inadequate conformability and device apposition along the inner curvature of the arch have been encountered. The new Conformable GORE® TAG® Thoracic Endoprosthesis (CTAG) is designed to have enhanced compression resistance and improved conformability in difficult anatomy. The present study compared the deployment accuracy and conformability of the CTAG Device with TAG Device.

  4. Dental arch relationship in children with complete unilateral cleft lip and palate following one-stage and three-stage surgical protocols

    NARCIS (Netherlands)

    Fudalej, P.S.; Katsaros, C.; Bongaarts, C.; Dudkiewicz, Z.; Kuijpers-Jagtman, A.M.

    2011-01-01

    The objective of this study is to compare dental arch relationship following one-stage and three-stage surgical protocols of unilateral cleft lip and palate. Dental casts of 61 children (mean age, 11.2 years; SD, 1.7), consecutively treated in one center with one-stage closure of the complete cleft

  5. Dental arch relationship in children with complete unilateral cleft lip and palate following warsaw (one-stage repair) and oslo protocols.

    NARCIS (Netherlands)

    Fudalej, P.S.; Hortis-Dzierzbicka, M.; Dudkiewicz, Z.; Semb, G.

    2009-01-01

    OBJECTIVE: To compare the dental arch relationship following one-stage repair of unilateral cleft lip and palate (UCLP) in Warsaw with a matched sample of patients treated by the Oslo Cleft Team. MATERIAL: Study models of 61 children (mean age, 11.2; SD, 1.7) with a nonsyndromic complete UCLP consec

  6. Evolution of magnetic topology of an erupting arched laboratory magnetoplasma

    Science.gov (United States)

    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

  7. The effect of minimal shoes on arch structure and intrinsic foot muscle strength

    Directory of Open Access Journals (Sweden)

    Elizabeth E. Miller

    2014-06-01

    Conclusion: These results suggest that endurance running in minimal support footwear with 4 mm offset or less makes greater use of the spring-like function of the longitudinal arch, thus leading to greater demands on the intrinsic muscles that support the arch, thereby strengthening the foot.

  8. Stability of clogging arches in a silo submitted to vertical vibrations

    Science.gov (United States)

    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.

  9. Rock-Arch Instability Characteristics of the Sandstone Plate under Different Loading Conditions

    Directory of Open Access Journals (Sweden)

    Shuren Wang

    2014-01-01

    Full Text Available Under the concentrated loading and the uniform loading, the tests on the brittle fracture and the hinged arching until the rock-arch instability of the sandstone plate were conducted using self-developed loading device, and the sensitivity of influent factors on the rock-arch failure was analyzed by numerical test based on the particle flow code (PFC. The results showed that sandstone plate instability presented four phases: small deformation elastic stage, brittle fracture arching stage, rock-arch bearing stage, and rock-arch instability stage. Under the uniform loading, the maximum vertical force of the rock-arch instability was much higher than that under the concentrated loading condition, but the maximum lateral force was almost the same. The number of acoustic emission (AE and its positioning results of the sandstone plate showed that the extent of the plate damage under the uniform loading was higher than that under the concentrated loading condition. The friction coefficient effect, size effect, loading rate effect, and the initial horizontal force effect on the rock-arch instability were analyzed by the PFC3D numerical experiment.

  10. "Roller coaster maneuver via lateral orbital approach" for reduction of isolated zygomatic arch fractures.

    Science.gov (United States)

    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. PMID:24220411

  11. Uinta Arch Project: investigations of uranium potential in Precambrian X and older metasedimentary rocks in the Unita and Wasatch ranges, Utah and Colorado

    International Nuclear Information System (INIS)

    This study is part of the United States Department of Energy's National Uranium Resource Evaluation Program to understand the geologic setting, amount, and availability of uranium resources within the boundaries of the United States. The systematic study of Precambrian quartz-pebble conglomerates and areas that may contain such conglomerates is an integral part of DOE's resource evaluation program, because deposits of world-wide importance occur in such terrains in Canada and South Africa, and because terrains similar to those producing uranium from quartz-pebble conglomerates exist elsewhere in the United States. Because of the ready availability of Tertiary sandstone and Colorado Plateau-type uranium deposits, large areas of Precambrian rocks in the US have not been fully assessed for uranium potential. Thus, the Uinta Arch Project was undertaken to assess the favorability of Precambrian metasedimentary rocks in northern Utah for deposits of uranium in Precambrian quartz-pebble conglomerates. Rocks of interest to this study are the thick, clastic sequences within the Uinta Arch that are considered to be of Early Proterozoic age. The Uinta Arch area is known to contain rocks which generally fit the lithologic characteristics that are understood to limit the occurrence of Precambrian fossil placers. However, detailed geology of these rocks and their exact fit to the model described for uraniferous conglomerates was not known. The primary goal of the Uinta Arch Project was to determine how well these Precambrian rocks resemble known deposits and to describe the favorability of placer uranium deposits

  12. Dynamic stability analysis of circular arch subjected to follower forces with small disturbances; Judo kaju wo ukeru enkei arch no yuran ni yoru doteki kyodo to anteisei kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Fukuchi, N.; Okada, K. [Kyushu University, Fukuoka (Japan). Faculty of Engineering; Hirano, Y. [Sumitomo Heavy Industries, Ltd., Tokyo (Japan)

    1997-09-04

    This paper describes the deformation and dynamic stability of circular arch subjected to follower forces in a submerged membrane type marine structure reinforced by arch frames. Governing equations for finite deformations of the circular arch subjected to follower forces are introduced using an embedded curve coordinate, which are formulated by applying Galerkin method. In addition, equations of motion due to small disturbances under given condition of loading are introduced. Based on these equations, dynamic stability of the arch is analyzed by means of Runnge-Kutta-Gill method, to clarify the relationship between disturbances and instability regions and the resulting phenomena. Near the boundary regions of stability, both amplitude and cycle of deformation are greatly affected by the amplitude of disturbances. The dynamic instability is governed by the inverse symmetry primary mode with minimum characteristic frequency which is specific for the circular arch. The dynamic stability has high parameter dependency, and the instability regions have a complicated shapes. Although flattened arch has a smaller static critical load, it provides the dynamic stability against the disturbance. 5 refs., 10 figs.

  13. The analysis of volatility of gold coin price fluctuations in Iran using ARCH & VAR models

    Directory of Open Access Journals (Sweden)

    Younos Vakilolroaya

    2014-03-01

    Full Text Available The aim of this study is to investigate the changes in gold price and modeling of its return volatility and conditional variance model. The study gathers daily prices of gold coins as the dependent variable and the price of gold in world market, the price of oil in OPEC, exchange rate USD to IRR and index of Tehran Stock Exchange from March 2007 to July 2013 and using ARCH family models and VAR methods, the study analysis the data. The study first examines whether the data are stationary or not and then it reviews the household stability, Arch and Garch models. The proposed study investigates the causality among variables, selects different factors, which could be blamed of uncertainty in the coin return. The results indicate that the effect of sudden changes of standard deviation and after a 14-day period disappears and gold price goes back to its initial position. In addition, in this study we observe the so-called leverage effect in Iran’s Gold coin market, which means the good news leads to more volatility in futures market than bad news in an equal size. Finally, the result of analysis of variance implies that in the short-term, a large percentage change in uncertainty of the coin return is due to changes in the same factors and volatility of stock returns in the medium term, global gold output, oil price and exchange rate fluctuation to some extent will show the impact. In the long run, the effects of parameters are more evident.

  14. Markedly hypoplastic circumflex retroesophageal right aortic arch: MR imaging and surgical implications

    International Nuclear Information System (INIS)

    Circumflex retroesophageal right aortic arch with a markedly hypoplastic retroesophageal segment is a rare anomaly of the aortic arch. Adequate surgical management relies on precise diagnosis, which might not be feasible with echocardiography. To demonstrate the utility of MR imaging in establishing the diagnosis and to describe potential pitfalls in making the diagnosis. Three patients with a circumflex retroesophageal right aortic arch with a markedly hypoplastic retroesophageal segment were retrospectively evaluated. All patients underwent evaluation by echocardiography and MR imaging. The MR imaging consisted of 3-D MR angiography in two patients and fast gradient recalled echo with cardiac-triggered segmented acquisition in one patient. Surgical confirmation was obtained on all three patients. The arch anatomy was accurately depicted in all three patients by MR imaging and in none of the patients by echocardiography. MR imaging is extremely useful in establishing the diagnosis of markedly hypoplastic retroesophageal circumflex right aortic arch and thus helps in surgical planning. (orig.)

  15. A shared role for sonic hedgehog signalling in patterning chondrichthyan gill arch appendages and tetrapod limbs.

    Science.gov (United States)

    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. PMID:27095494

  16. Preliminary research on cycloid as a line type of the arch dam

    Institute of Scientific and Technical Information of China (English)

    DU Tingna; YE Rongbo; ZHAO Haifeng

    2012-01-01

    Currently, there are a wide range of line types in the field of arch dam designing and construction, and each of them may have their own strength and weakness disparately. A trade-off between the size, stress, as well as the construction cost and complex- ity of the dam needs to be made in order to arrive at a new solution called the cycloid arch dam. Through redevelopment of VBA us- ing AutoCAD, the arch ring and the center of the arch line have been designed. Also, the stress analysis on parabola and cycloid have been done, which provides a theoretical principle that the cycloid could be regarded as a new line type of the arch dam.

  17. Automatic dental arch detection and panoramic image synthesis from CT images.

    Science.gov (United States)

    Sa-Ing, Vera; Wangkaoom, Kongyot; Thongvigitmanee, Saowapak S

    2013-01-01

    Due to accurate 3D information, computed tomography (CT), especially cone-beam CT or dental CT, has been widely used for diagnosis and treatment planning in dentistry. Axial images acquired from both medical and dental CT scanners can generate synthetic panoramic images similar to typical 2D panoramic radiographs. However, the conventional way to reconstruct the simulated panoramic images is to manually draw the dental arch on axial images. In this paper, we propose a new fast algorithm for automatic detection of the dental arch. Once the dental arch is computed, a series of synthetic panoramic images as well as a ray-sum panoramic image can be automatically generated. We have tested the proposed algorithm on 120 CT axial images and all of them can provide the decent estimate of the dental arch. The results show that our proposed algorithm can mostly detect the correct dental arch.

  18. 结合梁桥面系异形钢箱拱肋系杆拱桥设计%Design of Special-shaped Steel Box Arch Rib Bowstring Arched Bridge of Bonding Beam Deck System

    Institute of Scientific and Technical Information of China (English)

    李文勃

    2009-01-01

    The main bridge of Putian Chenggang Avenue Bridge crossing Molan River is the special-shaped bowstring arched bridge of 2-span simple-supported double-rib half-through steel box arch rib bonding beam deck system. The single span is 72 m long and the bridge is 47.5 m wide with city-Class A load and double-direction of 8 lanes. Taking the preliminary design and construction drawing design of this bridge as the basis, the article introduces the scheme study of bridge type, structural design of main bridge and analysis of structural calculation of the special-shaped bowstring arched bridge, and analyzes some technical characteristics of this bridge. The design method of the main bridge inclined crossed with the curve river, the design thinks of bonding beam in the arched bridge, the temporary constructed supporting point for improving the structural bearing, and the design method of special arch rib modeling can be referred for the design of the similar bridges.%莆田城港大道跨木兰溪大桥主桥是两跨简支的双肋下承式钢箱拱肋结合梁桥面系的异形系杆拱桥,单跨跨径72m,桥宽47.5m,城一A级荷载,双向8车道.该文以该桥的初步设计和施工图设计为基础,介绍了异形系杆拱桥的桥型方案研究、主桥结构设计、结构计算分析等内容,并分析了该桥的一些技术特点.该桥的弯曲河道斜交主桥设计方法、结合梁在拱桥中的设计思想、结合梁横梁设置临时支点改善结构受力、独特拱肋造型的设计方法等内容,可供类似桥梁设计时参考.

  19. File list: InP.Emb.50.AllAg.Maxillary_arch_junction [Chip-atlas[Archive

    Lifescience Database Archive (English)

    Full Text Available InP.Emb.50.AllAg.Maxillary_arch_junction mm9 Input control Embryo Maxillary arch jun...ction http://dbarchive.biosciencedbc.jp/kyushu-u/mm9/assembled/InP.Emb.50.AllAg.Maxillary_arch_junction.bed ...

  20. File list: NoD.Emb.05.AllAg.Maxillary_arch_junction [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  1. File list: InP.Emb.10.AllAg.Maxillary_arch_junction [Chip-atlas[Archive

    Lifescience Database Archive (English)

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    Lifescience Database Archive (English)

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    Lifescience Database Archive (English)

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    Lifescience Database Archive (English)

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    Lifescience Database Archive (English)

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  6. File list: InP.Emb.20.AllAg.Maxillary_arch_junction [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  7. Numerical dynamic analysis of Chiti single arch dam related to hydroelectric power generation

    Energy Technology Data Exchange (ETDEWEB)

    Abbasi, H. [Islamic Azad Univ., Tehran (Iran, Islamic Republic of); Hosseini, Y.; Jalaly, H. [Ab-Niru Consulting Engineers, Tehran (Iran, Islamic Republic of); Aghajani, K. [Elam Univ., Elam (Iran, Islamic Republic of)

    2006-07-01

    The Chiti dam is a single arch hydroelectric power generation dam located on the Taloogh River in Iran. This paper provided details of the response spectrum method used to design the optimal load conditions and slope of the dam in relation to earthquake protection. The amount of horizontal earthquake acceleration at the dam site was determined based on local calculations of scenarios of an operating basis earthquake (OBE), a maximum design earthquake (MDE) and a maximum credible earthquake (MCE). The response spectrum was defined with 5 per cent damping as the basis of the earthquake calculation. Hydrodynamic pressure was applied in loadings and the dam was analyzed with and without the effect of hydrodynamic pressure. The compressive strength of the concrete was considered as 28 MPa, and the properties of bed rock were determined on geotechnical and geological studies. Hydrodynamic pressure was calculated based on upstream water levels in the reservoir of the arch dam and applied to the model as added mass. The model also considered the weight of the dam body, uplift pressure, and heat changes in stable conditions. The hydrodynamic pressure of water was applied as additional mass to the upstream face of the arch dam. The additional mass was determined based on dam height. The dynamic analysis of the dam was performed using response spectrum data. The model analysis was performed with and without the effect of hydrodynamic pressure. The 3-D model of the dam body was made using the ANSYS finite element program which combined the response spectrum method with temperature load, uplift pressure and water pressure parameters. Results showed that the maximum displacement of the dam body for the various earthquake levels measured was 11.6, 14, and 15.6 mm respectively. The response spectrum analysis performed with hydrodynamic pressure showed displacement values of 22.4, 24.8, and 26.4 mm. Stress and strain values obtained by the model were within allowable amount for

  8. The Evolution of Protoplanetary Discs in the Arches Cluster

    CERN Document Server

    Olczak, C; Harfst, S; Pfalzner, S; Zwart, S Portegies

    2012-01-01

    Most stars form in a cluster environment. These stars are initially surrounded by discs 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 favour rapid destruction of circumstellar discs 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 discs in a prototypical starburst cluster. Despite its proximity to the deep gravitational potential of the Galactic centre 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 discs 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 we...

  9. Variation in the Branching Pattern of the Superficial Palmar Arch

    Directory of Open Access Journals (Sweden)

    Sumalatha S

    2016-05-01

    Full Text Available In this article we describe a rare variation in the superficial palmar arch (SPA encountered during routine cadaveric dissection. SPA was formed by the superficial branches of ulnar and radial arteries which provided a proper digital branch to the ulnar side of the little finger and three common palmar digital branches to the medial four digits. Additionally a first common digital artery was seen to emerge from the radial side of SPA which further divided into the arteria princeps pollicis and arteria radialis indicis. We also found a small communicating branch between the arteria princeps pollicis and the radial artery in the anatomical snuff box. Such arterial variations in the palm due to alteration in the developmental sequence remains a crucial issue in the reconstructive hand surgeries, especially while dealing with the innovative microsurgical procedures, where these varied patterns act as pivotal points around which successful results of various advanced surgical procedures revolve.

  10. Bacteroides fragilis aortic arch pseudoaneurysm: case report with review

    Directory of Open Access Journals (Sweden)

    Yang Yu-Jen

    2008-05-01

    Full Text Available Abstract We present a case of 58-year-old woman with underlying diabetes mellitus, hepatitis C virus-related liver cirrhosis, and total hysterectomy for uterine myoma 11 moths ago, who was diagnosed ruptured aortic arch mycotic pseudoaneurysm after a certain period of survey for her unknown fever cause. After emergent surgery with prosthetic graft interposition, all her blood cultures and tissue cultures revealed pathogen with Bacteroides fragilis. Although mycotic aneurysms have been well described in literatures, an aneurysm infected solely with Bacteroides fragilis is unusual, with only eight similar cases in the literature. Here we reported the only female case with her specific clinical and management course and summarized all reported cases of mycotic aneurysm caused by Bacteroides fragilis to clarify their conditions and treatments, alert the difficulty in diagnosis, and importance of highly suspicious.

  11. SIMULATION FRAMEWORK FOR REGIONAL GEOLOGIC CO{sub 2} STORAGE ALONG ARCHES PROVINCE OF MIDWESTERN UNITED STATES

    Energy Technology Data Exchange (ETDEWEB)

    Sminchak, Joel

    2012-09-30

    This report presents final technical results for the project Simulation Framework for Regional Geologic CO{sub 2} Storage Infrastructure along Arches Province of the Midwest United States. The Arches Simulation project was a three year effort designed to develop a simulation framework for regional geologic carbon dioxide (CO{sub 2}) storage infrastructure along the Arches Province through development of a geologic model and advanced reservoir simulations of large-scale CO{sub 2} storage. The project included five major technical tasks: (1) compilation of geologic, hydraulic and injection data on Mount Simon, (2) development of model framework and parameters, (3) preliminary variable density flow simulations, (4) multi-phase model runs of regional storage scenarios, and (5) implications for regional storage feasibility. The Arches Province is an informal region in northeastern Indiana, northern Kentucky, western Ohio, and southern Michigan where sedimentary rock formations form broad arch and platform structures. In the province, the Mount Simon sandstone is an appealing deep saline formation for CO{sub 2} storage because of the intersection of reservoir thickness and permeability. Many CO{sub 2} sources are located in proximity to the Arches Province, and the area is adjacent to coal fired power plants along the Ohio River Valley corridor. Geophysical well logs, rock samples, drilling logs, and geotechnical tests were evaluated for a 500,000 km{sup 2} study area centered on the Arches Province. Hydraulic parameters and historical operational information was also compiled from Mount Simon wastewater injection wells in the region. This information was integrated into a geocellular model that depicts the parameters and conditions in a numerical array. The geologic and hydraulic data were integrated into a three-dimensional grid of porosity and permeability, which are key parameters regarding fluid flow and pressure buildup due to CO{sub 2} injection. Permeability data

  12. SIMULATION FRAMEWORK FOR REGIONAL GEOLOGIC CO{sub 2} STORAGE ALONG ARCHES PROVINCE OF MIDWESTERN UNITED STATES

    Energy Technology Data Exchange (ETDEWEB)

    Sminchak, Joel

    2012-09-30

    This report presents final technical results for the project Simulation Framework for Regional Geologic CO{sub 2} Storage Infrastructure along Arches Province of the Midwest United States. The Arches Simulation project was a three year effort designed to develop a simulation framework for regional geologic carbon dioxide (CO{sub 2}) storage infrastructure along the Arches Province through development of a geologic model and advanced reservoir simulations of large-scale CO{sub 2} storage. The project included five major technical tasks: (1) compilation of geologic, hydraulic and injection data on Mount Simon, (2) development of model framework and parameters, (3) preliminary variable density flow simulations, (4) multi-phase model runs of regional storage scenarios, and (5) implications for regional storage feasibility. The Arches Province is an informal region in northeastern Indiana, northern Kentucky, western Ohio, and southern Michigan where sedimentary rock formations form broad arch and platform structures. In the province, the Mount Simon sandstone is an appealing deep saline formation for CO{sub 2} storage because of the intersection of reservoir thickness and permeability. Many CO{sub 2} sources are located in proximity to the Arches Province, and the area is adjacent to coal fired power plants along the Ohio River Valley corridor. Geophysical well logs, rock samples, drilling logs, and geotechnical tests were evaluated for a 500,000 km{sup 2} study area centered on the Arches Province. Hydraulic parameters and historical operational information was also compiled from Mount Simon wastewater injection wells in the region. This information was integrated into a geocellular model that depicts the parameters and conditions in a numerical array. The geologic and hydraulic data were integrated into a three-dimensional grid of porosity and permeability, which are key parameters regarding fluid flow and pressure buildup due to CO{sub 2} injection. Permeability data

  13. Impact of global financial crisis on precious metals returns: An application of ARCH and GARCH methods

    Science.gov (United States)

    Ismail, Mohd Tahir; Abdullah, Nurul Ain; Abdul Karim, Samsul Ariffin

    2013-04-01

    This paper is focusing on seeing the resilient of precious metals returns in facing the global financial crisis and provides a new guide for the investors before making investment decisions on precious metals. Four types of precious metals returns which are the variables selected in this study. The precious metals are gold, silver, bronze and platinum. All the variables are transferred to natural logarithm (ln). Daily data over the period 2 January 1995 to 30 December 2011 is used. Unit root tests that involve Augmented Dickey-Fuller (ADF) and Kwiatkowski-Phillips-Schmidt-Shin (KPSS) tests have been employed in determining the stationarity of the variables. Autoregressive Conditional Heteroscedasticity (ARCH) and Generalized Autoregressive Conditional Heteroscedasticity (GARCH) methods have been applied in measuring the impact of global financial crisis on precious metals returns. The result shows that investing in platinum is less risky compared to the other precious metals because it is not influence by the crisis period.

  14. Dynamic Behavior of Tied-Arch Bridges under the Action of Moving Loads

    Directory of Open Access Journals (Sweden)

    Paolo Lonetti

    2016-01-01

    Full Text Available The dynamic behavior of tied-arch bridges under the action of moving load is investigated. The main aim of the paper is to quantify, numerically, dynamic amplification factors of typical kinematic and stress design variables by means of a parametric study developed in terms of the structural characteristics of the bridge and moving loads. The basic formulation is developed by using a finite element approach, in which refined schematization is adopted to analyze the interaction between the bridge structure and moving loads. Moreover, in order to evaluate, numerically, the influence of coupling effects between bridge deformations and moving loads, the analysis focuses attention on usually neglected nonstandard terms in the inertial forces concerning both centripetal acceleration and Coriolis acceleration. Sensitivity analyses are proposed in terms of dynamic impact factors, in which the effects produced by the external mass of the moving system on the dynamic bridge behavior are evaluated.

  15. The behaviour of a historic masonry arch bridge regarding dynamic loads

    Directory of Open Access Journals (Sweden)

    Yesid Mauricio Ospina

    2010-05-01

    Full Text Available This article describes the analysis of a historic brick arch bridge constructed in Colombia during the 18th century for predicting its behavior in response to loads produced by seismic activity and determining its vulnerability. Two studies were carried out prior to the seismic analysis to obtain basic information regarding the structure's overall behavior (modal analysis and linear static analy- sis, both stemming from a three-dimensional model constructed by the finite elements method. Seismic excitation was simulated in the conditions proposed by 1998 Colombian seismic-resistant norms (NSR-98. The results obtained agreed with the bridge’s history and with its response to earthquakes; the comparison between seismic loads and the resistance capacity of the materials constituting the structure confirms the vulnerability of these types of constructions regarding localised damage and the possibility of collapse. The results suggest that this procedure can be applied to other historic structures in Colombia.

  16. Outcomes of single-stage total arch replacement via clamshell incision

    Directory of Open Access Journals (Sweden)

    Ishizaka Toru

    2011-09-01

    Full Text Available Abstract Background Treatment of complex aortic pathologies involving the transverse arch with extensive involvement of the descending aorta remains a surgical challenge. Since clamshell incision provides superior exposure of the entire thoracic aorta, we evaluated the use of this technique for single-stage total arch replacement by arch vessel reconstruction. Methods The arch-first technique combined with clamshell incision was used in 38 cases of aneurysm and aortic disease in 2008 and 2009. Extensive total arch replacement was used with clamshell incision for reconstruction of arch vessels under deep hypothermic circulatory arrest. Results Overall 30-day mortality was 13%. The mean operating time was approximately 8 hours. Deep hypothermia resulted in mean CPB time exceeding 4.5 hours and mean duration of circulatory arrest was 25 minutes. The overall postoperative temporary and permanent neurologic dysfunction rates were 3% and 3% for elective and 3% and 0% for emergency surgery, respectively. All patients except the five who died in hospital were discharged without nursing care after an average post-operative hospital stay of 35 days. Conclusions The arch-first technique, combined with clamshell incision, provides expeditious replacement of the thoracic aorta with an acceptable duration of hypothermic circulatory arrest and minimizes the risk of retrograde atheroembolism by using antegrade perfusion.

  17. [Effects of removable partial dentures on the quality of life in people with shortened dental arches].

    Science.gov (United States)

    Armellini, D B; Heydecke, G; Witter, D J; Creugers, N H J

    2009-12-01

    In order to assess the enhanced value of removable partial dentures on the quality of life, patients at 2 university clinics were screened for the presence of complete or shortened dental arches. Those selected were assigned to 1 of 5 subgroups: 1) a shortened dental arch with all frontal teeth, 2) a shortened dental arch with one or more frontal diastemas, 3) a shortened dental arch with all frontal teeth, restored by a removable partial denture, 4) a shortened dental arch and several diastemas, restored by a removable partial denture, 5) a complete dental arch. The participants completed the Oral Health Impact Profile (OHIP-49) and the Short Form Health Survey (SF-36). Clinical data recorded were: whether any teeth were missing and if so which, whether or not these had been replaced by a removable partial denture, and the number of occluding pairs of (pre)molars. The results revealed that a shortenend dental arch has a certain impact on the quality of life. However, the participants only experienced benefits from a removable partial denture if the denture also replaced frontal teeth. PMID:20101937

  18. Differences in functional outcomes for adult patients with prosthodontically-treated and -untreated shortened dental arches: a systematic review.

    Directory of Open Access Journals (Sweden)

    Saadika Khan

    Full Text Available This review examined differences in functional outcomes and patient satisfaction when shortened dental arches are left untreated compared to their restoration to complete arch lengths with different prosthodontic interventions.A protocol was developed according to the criteria for a systematic review. All relevant databases were searched to identify appropriate clinical trials regardless of language or publication status. Predetermined eligibility criteria were applied, trial quality assessed and data extracted for each study. Relevant outcomes assessed were: functioning ability, patient satisfaction and harmful effects on oral structures.Searches yielded 101 articles: 81 from electronic databases and 20 from reference lists of retrieved articles (PEARLing searches. Sixty-nine citations were assessed for eligibility after removing 32 duplicate records. After reading titles and abstracts, a total of 41 records were excluded and the full-texts of the remaining 28 records were read. Only 21 records were included for the SR because 7 records were excluded after reading the full-text reports. These 21 records report the outcomes of four randomized controlled trials (RCTs and one non-randomized clinical trial (CT which were pre-specified and used for this review. No on-going studies were found and no eligible studies were excluded for failure to report the reviewer's pre-specified outcomes. Outcomes were reported in the retrieved 21 articles. A narrative explanation of the pre-specified outcomes is reported for the 3 comparison groups (which were based on the different interventions used for the individual clinical trials. The shortened dental arch as a treatment option is encouraging in terms of functioning, patient satisfaction and cost-effectiveness. By using only high quality studies it was expected that the results would be more reliable when making conclusions and recommendations, but some of the included studies had to be downgraded due to

  19. Influence of Process Parameters on Forming of Arched Aircraft Skin with Aluminum Alloy 2024

    Science.gov (United States)

    Yan, Huajun; Zhang, Shuangjie; Gao, Ying

    To solve these problems such as easily springback and hardly controlling the loading direction when arched aircraft skin is formed, stretch forming of steel plate with aluminium alloy 2024 was simulated by the finite element software Abaqus, and the shape of the stretch forming die was the arc with radius 350mm. The influence of process parameters, such as stretch forming track and dangling length on forming of arched aircraft skin was researched, and the reasonable range of stretch forming length track and dangling length was given. The results have significance for research the forming law of arched aircraft skin.

  20. Seismic response analysis of arch dam-water-rock foundation systems

    Institute of Scientific and Technical Information of China (English)

    杜修力; 王进廷

    2004-01-01

    The effect of water compressibility on the seismic responses of arch dams is not well understood. In this paper, a numerical model is developed with rigorous representation of the dynamic interaction between arch dam-waterrock foundation. The model is applied to the seismic response analysis of an arch dam with a height of 292m designed to a seismic intensity of Ⅸ. It is shown that consideration of the water compressibility clearly decreases the stress responses at key positions of the dam, while the added mass model gives a conservative estimate.

  1. Research on Multi-Parameter of Butterfly Arched Bridge Stability%蝴蝶拱桥稳定性多参数影响研究

    Institute of Scientific and Technical Information of China (English)

    段锋

    2012-01-01

    以某蝴蝶拱桥为工程背景,建立该桥的空间有限元计算模型,分4个工况计算了该桥的稳定安全系数。通过改变拱肋外倾角度、拱肋刚度、端横梁刚度以及吊杆布置形式计算了不同设计参数下结构在恒栽工况以及恒载+活载工况的失稳特征值。结果表明,拱肋的刚度对稳定性起着决定性作用;吊杆的布置形式只改变拱肋的面内刚度,对于面外刚度没有影响。%Taking some butterfly arched bridge as the engineering background, the study establishes tile spatial finite ele- ment computation model of the bridge, and the stability safety index is calculated in four kinds of construction conditions. Through the change of arch rib camber angle, rigidity of the arch rib, the end beam rigidity as well as the arrangement of suspension bar, imbalance eigen values of the structure are calculated in the dead load operating mode as well as the dead load + live load operating mode. The result indicates that, the arch rib rigidity plays a decisive role in the stability; The suspension bar arrangement only changes the arch rib in plane rigidity and has nothing to do without plane rigidity.

  2. Histoire tertiaire de l'Arche de Brahmaputra ; son rôle dans la prospection des hydrocarbures du Haut Assam (Inde (résumé Tertiary History of Brahmaputra Arch. Its Role in Hydrocarbon Prospects of Upper Assam, India (Abstract

    Directory of Open Access Journals (Sweden)

    Murty K. N.

    2006-10-01

    Full Text Available On analyse l'histoire tertiaire de la plate-forme du Haut Assam (Inde et on discute les facteurs géologiques responsables du caractère pétrolier de cette importante province ainsi que ses relations avec la ceinture mobile de Naga au Sud-Est et avec l'avant-fosse himalayenne au Nord-Ouest. A cette intention, on a préparé des cartes paléologiques pour différentes formations dans la vallée supérieure de l'Assam, basées sur de nombreux puits et levers géophysiques. A partir de ces cartes, on a construit une série de coupes paléogéologiques pour illustrer l'évolution structurale de la plate-forme du haut Assam. Cette étude montre que la structure régionale de la haute vallée de l'Assam est en subsurface une arche large - l'Arche de Brahrnaputra - parallèle à, et juste au sud de la rivière Brahmaputra, formée par un double basculernent opposé : un ancien talus vers le Sud-Est durant le Paléogène et l'autre tourné vers le Nord-Ouest pendant le Mio-Pliocène. On peut identifier deux phases de migration des hydrocarbures. L'étude permet l'affirmation d'objectifs futurs en Haut Assam. Cette arche a une histoire géologique voisine de celle de l'arche de Bend du centre-nord du Texas et de l'arche de Hunton-Seminole-Ozark en Oklahoma où de riches gisements ont été trouvés dans presque tous les terrains impliqués dans le bombement. The Tertiary history of Upper Assam shelf, India is analysed. The geological factors responsible for making this an important petroleum province and ifs relationship with the Nago mobile belt in the south-east and the Himalayan fore deep in the north-vvest ore discussed. Sub-crop maps of différent geological formations in Upper Assam Valley based on a number of drilled wells and various geophysical surveys ore prepared for this purpose. From these maps, a series of palaeogeological sections are constructed to illustrate the structural evolution of the Upper Assam shelf. The study reveals thot the

  3. 特克斯河山口引水枢纽的 引水防沙设计及试验研究%Dynamic test and study on the integral body and model with transverse joint of Xiaowan High Arch Dam

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    通过特克斯河山口引水枢纽的试验研究,解决了常遇洪水低水位运行时河流两岸的引水问题,优化了水平悬板等结构形式,收到了较好的引水防沙效果,为悬板分层式引水枢纽工程设计提供了新经验%The dynamic test on the earthquake response of the integral dam body and model with transverse joint for Xiaowan High Arch Dam was made. In consideration that the dynamic test on the model with transverse joint falls into non-linear category, it is more sensitive to the initial condition of static action so that the test includes reservoir with a length of three times dam height. The test on expansion transverse joint was made in two working conditions. Firstly three expansion transverse joints were set up in the arch-crown beam and top arch, about 1/4 arc length of right and left banks. Then five transverse joints were increased to make dynamic test. The test showed that under the working condition of normal high water level, the transverse joint of dam body under the action of earthquake opens indistinctly. But under the low water level, the transverse joint clearly opens because of the reduction of static pressure. The dynamic tensile stress of dam body obviously reduces and the dynamic beam stress increases obviously. The initial condition of the transverse joints of dam body will bring big impact on the opening of transverse joint. On the basis of the designed reinforcement, the test showed that the opening of transverse joint reduced about 20%.

  4. The Comparison of Different Degree of Convexity and 3D Modeling of Involute Hyperbolic Arch Dam

    Institute of Scientific and Technical Information of China (English)

    DU Qi-lu; DU Ting-na; ZHAO Hai-feng

    2011-01-01

    Because of good quality of compressive resistance, the hyperbolic arch dam is being increasingly applied to engineering projects. In order to satisfy the needs of compressive resistance under the conditions of high water pressure, a stress analysis is required for the dam. During the stress analysis process however, due to the complexity of the three-dimensional modeling, it is very hard to form a model. Therefore, the stress analysis process is a barrier for the arch dam. In this article, based on the research of the new line-type arch dam, a mathematical model in different degree of convexity conditions of the dam is established; using the C + + language program, a computer three-dimensional model simulation is realized on AutoCAD. The accurate three-dimensional model is providing a finite element optimization design of the involute hyperbolic arch dam for the next step.

  5. RCC Arch Dam Structure on the Taxi River and Water Storage Measure During Construction

    Institute of Scientific and Technical Information of China (English)

    刘光廷; 李鹏辉; 胡昱; 张富德; 谢树南

    2002-01-01

    The new structure of roller compacted concrete (RCC) arch dams is presented for extremely cold and earthquake prone areas. The influence of construction plans and improved materials on the stresses in the Taxi River dam is also given. Earlier impoundment of water is shown to not only benefit the engineering design but also improve the stresses during construction in winter. Low cement content in the concrete and artificial short joints improved the monolithic structure and the transmitted forces. The concrete plug installed in the first cooled part of the arch dam provides excellent force transmission in the arch, which increases the monolith of the earlier arch, reduces the increasing thermal stresses that occur later, and improves the deformation flexibility of the dam.

  6. Right aortic arch with aberrant left innominate artery arising from Kommerell's diverticulum*

    Science.gov (United States)

    Faistauer, Ângela; Torres, Felipe Soares; Faccin, Carlo Sasso

    2016-01-01

    We report a case of an uncommon thoracic aorta anomaly-right aortic arch with aberrant left innominate artery arising from Kommerell's diverticulum-that went undiagnosed until adulthood. PMID:27777481

  7. Kilconnell Franciscan Friary, north chancel wall, tomb niche, jamb and arch

    OpenAIRE

    O'Donovan, Danielle

    2001-01-01

    Jamb and arch moulding of canopied niche in north chancel wall. Moulding from intrados comprises: quadrant, hollow chamfer, quadrant, flat surface running into hollow, mitre, hollow chamfer, quadrant, hollow chamfer.

  8. Timoleague Franciscan Friary, north nave wall, tomb niche, jamb, arch and hood

    OpenAIRE

    O'Donovan, Danielle

    2004-01-01

    Jamb, arch and hood moulding of tomb niche. From intrados, moulding comprises quardant, right-angled rebate, quadrant. The hood, from outer moulding to inner, comprises a frontal fillet, hollow chamfer quadrant.

  9. Computed tomography angiography of hybrid thoracic endovascular aortic repair of the aortic arch.

    Science.gov (United States)

    Akhtar, Nila J; Oderich, Gustavo S; Vrtiska, Terri J; Williamson, Eric E; Araoz, Philip A

    2013-05-01

    Endovascular repair of the aorta has traditionally been limited to the abdominal aorta and, more recently, the descending thoracic aorta. However, recently hybrid repairs (a combination of open surgical and endovascular repair) have made endovascular repair of the aortic arch possible. Hybrid repair of the aortic arch typically involves an open surgical debranching procedure that allows for revascularization of the aortic arch vessels and subsequent endovascular stent placement. These approaches avoid the deep hypothermic circulatory arrest required for full, open surgical repair of the aortic arch. In hybrid repairs, the stent landing zone determines which branch vessels will be covered and therefore need revascularization. This article will review the preprocedure assessment with computed tomography angiography, techniques for revascularization and postprocedure complications. PMID:23621141

  10. Dermatoglyphic Assessment in Subjects with Different Dental Arch Forms: An Appraisal

    OpenAIRE

    Sachdeva, Shabina; Tripathi, Arvind; Kapoor, Pranav

    2013-01-01

    Successful rehabilitation of edentulous individuals involves selection and arrangement of artificial teeth in accordance with the patient’s original arch form. Various criteria exist for harmonious tooth arrangement but none is accepted universally. Finger and palm prints are unique to an individual and once formed in the sixth week of intra-uterine life, remain constant thereafter. Since dental arches are also formed during the same prenatal period, it is believed that the similar genetic fa...

  11. Continuum analysis of common branching patterns in the human arch of the aorta.

    Science.gov (United States)

    Zamir, M; Sinclair, P

    1990-01-01

    A model is proposed for describing common variations in the arrangement of branches on the arch of the human aorta, and the model is used to analyze data from 123 human arches. The analysis allows the observed variations to fall freely along a continuous spectrum, rather than be confined to discrete categories as is commonly done at present. The results thus describe these variations in a more natural way and throw some new light on their likely source.

  12. Comparison Of Medial Arch-Supporting Insoles And Heel Pads In The Treatment Of Plantar Fasciitis

    Directory of Open Access Journals (Sweden)

    Malkoc Melih

    2015-03-01

    Full Text Available Plantar fasciitis is a disorder caused by inflammation of the insertion point of the plantar fascia over the medial tubercle of the calcaneus. Foot orthotics are used to treat plantar fasciitis. Heel pads medialise the centre of force, whereas medial arch supporting insoles lateralise the force. We assessed the clinical results of the treatment of plantar fasciitis with silicone heel pads and medial arch-supported silicone insoles.

  13. Dentures as Learning Materials for Maxillomandibular Fixation by Erich Arch Bars.

    Science.gov (United States)

    Aksam, Ersin; Aksam, Berrak

    2016-03-01

    Maxillomandibular fixation with Erich arch bars is an economic method for handling mandibular fractures. Unfortunately, this method has some disadvantages, such as long operating time, periodontal trauma, and risk of puncture injury to the operator. To overcome these disadvantages, we propose teaching the pits and pearls of maxillomandibular fixation with Erich arch bars to trainees using dentures of a patient. Experiencing the method on dentures will shorten the learning curve.

  14. ARCH and GARCH Models vs. Martingale Volatility of Finance Market Returns

    OpenAIRE

    Joseph L. McCauley

    2008-01-01

    ARCH and GARCH models assume either i.i.d. or (what economists lable as) white noise as is usual in regression analysis while assuming memory in a conditional mean square fluctuation with stationary increments. We will show that ARCH/GARCH is inconsistent with uncorrelated increments, violating the i.i.d. and white assumptions and finance data and the efficient market hypothesis as well.

  15. Calculation and Analysis of Internal Force in Arch Structure of Frozen Soil

    Institute of Scientific and Technical Information of China (English)

    YUE Feng-tian; ZHANG Yong; SHI Rong-jian

    2005-01-01

    Aimed at the frozen soil arch reinforcement form of upside shed used for the shield machine launching in tunneling the internal force of the structure was calculated with the aid of the structural mechanics theory. Considering the space characteristics of the structure,this calculating method is suitable for practical engineering.Moreover,the behavior of the freezing arch reinforcement structure was analyzed combined with an engineering case.

  16. The massive star Initial Mass Function of the Arches cluster

    CERN Document Server

    Espinoza, Pablo; Melnick, Jorge

    2009-01-01

    The massive Arches cluster near the Galactic Center is in principle an ideal laboratory to investigate massive star formation under extreme conditions. But it comes at a high price: the cluster is hidden behind several tens of magnitudes of visual extinction. Severe crowding requires space or AO-assisted instruments to resolve the stellar populations, and even with the best instruments the interpretation of the data is far from direct. Several investigations using NICMOS and the most advanced AO imagers on the gro und revealed an overall top-heavy IMF for the cluster, with a very flat IMF near the center. There are a number of effects, however, that could potentially bias these results, in particular the strong differential extinction and the problem of transforming the observations to a standard photometric system in the presence of strong reddening. We present new observations obtained with the NAOS-Conica (NACO) AO-imager on the VLT. The problem of photometric transformation is avoided by working in the na...

  17. Analysis of the pedestrian arching at bottleneck based on a bypassing behavior model

    Science.gov (United States)

    Tang, Ming; Jia, Hongfei; Ran, Bin; Li, Jun

    2016-07-01

    A bypassing behavior model was proposed, in which the local optimal decision behavior in the strategy level was modeled in velocity-time domain, to describe how pedestrians bypass the local obstacles considering the relative speed. The model contains (1) pedestrian visual and contact information acquisition; (2) motion state prediction of the local obstacles based on the visual and contact information; (3) pedestrian bypass strategy modeling in the velocity-time domain; (4) moving and overlapping solution. In the numerical solution, velocity domain was divided into n equal angle, the value of n ranges from 2 to infinity, the Manhattan space was refined gradually to Euclid Space accordingly, in which the movement of pedestrians was described. The model was applied to the analysis of pedestrian arching at the bottleneck in the emergent evacuation situation. (1) The results showed that the formation of the pedestrian arching at the bottleneck was deformation pressure, because many pedestrians try to pass through the bottleneck simultaneously, even in the absence of friction, the pedestrian arching still occurs; (2) In the emergent situation, we are more concerned about the bottleneck attribution of resistance to form the arching, the calculation and simulation results showed that the probability of an arching and the bottleneck width is an exponential function relationship, so when the stampede occurs in the middle of the bottleneck, the probability of arching will increase exponentially.

  18. Analysis of seismic disaster failure mechanism and dam-break simulation of high arch dam

    Science.gov (United States)

    Zhang, Jingkui; Zhang, Liaojun

    2014-06-01

    Based on a Chinese national high arch dam located in a meizoseismal region, a nonlinear numerical analysis model of the damage and failure process of a dam-foundation system is established by employing a 3-D deformable distinct element code (3DEC) and its re-development functions. The proposed analysis model considers the dam-foundation-reservoir coupling effect, influence of nonlinear contact in the opening and closing of the dam seam surface and abutment rock joints during strong earthquakes, and radiation damping of far field energy dissipation according to the actual workability state of an arch dam. A safety assessment method and safety evaluation criteria is developed to better understand the arch dam system disaster process from local damage to ultimate failure. The dynamic characteristics, disaster mechanism, limit bearing capacity and the entire failure process of a high arch dam under a strong earthquake are then analyzed. Further, the seismic safety of the arch dam is evaluated according to the proposed evaluation criteria and safety assessment method. As a result, some useful conclusions are obtained for some aspects of the disaster mechanism and failure process of an arch dam. The analysis method and conclusions may be useful in engineering practice.

  19. Implant restoration of edentulous jaws with 3D software planning, guided surgery, immediate loading, and CAD-CAM full arch frameworks

    OpenAIRE

    Silvio Mario Meloni; Giacomo De Riu; Milena Pisano; Francesco Maria Lolli; Alessandro Deledda; Guglielmo Campus; Antonio Tullio

    2013-01-01

    Purpose. The aim of this study was to analyze the clinical and radiographic outcomes of 23 edentulous jaws treated with 3D software planning, guided surgery, and immediate loading and restored with CAD-CAM full arch frameworks. Materials and Methods. This work was designed as a prospective case series clinical study. Twenty patients have been consecutively rehabilitated with an immediately loaded implant supported fixed full prosthesis. A total of 120 fixtures supporting 23 bridges were place...

  20. Effects of different types of palatal lateral excisions on growth and development of maxilla and dental arch

    Institute of Scientific and Technical Information of China (English)

    Jun WU; Qian ZHENG; Bing SHI; Tian MENG; Yan WANG; Sheng LI; Lishu LIAO

    2008-01-01

    Obiective:This study aimed to explore the effects of different types of palatal lateral excisions on the growth and deveiopment of the maxilla and dental arch.and to investigate the underlying mechanisms.Methods:A total of 1123-week-old Sprague-Dawley(SD)male rats were randomly divided into a control and 3 experimental groups:the mucoperiosteal denudation group,the mucosal flap excision group,and the periosteum excision group.In the experimental groups,bilateral mucoperiosteal,mucosal flap and periosteum were excised respectively in the lateral one half of the palate.Four rats in each group were randomly chosen for sacrifice every two weeks.The maxilla was dissected following the excision.The widths of the maxilla and dental arch were measured and the histological phenomena were investigated at different phases.At the same time.12 animals in each group were sequentially injected with calcein every two weeks.Three animals in each group,whose fluorescent labeling was used,were sacrificed for investigating bone formation at Week 8 following injection.Results:(1)Each experimental group presented the constriction of the maxilla and dental arch.The upper first molars in the experimental groups inclined medially.The mucoperiosteal denudation group showed the largest degree of effect followed by the periosteum excision group.The indices of the mucosal flap excision group,which retained the structures of the periosteum layer,had the most approximate values to the control group;(2)Different histological changes among the experimental groups were detected.The fibers penetrated into the palatal bone asSharpey's fibers in the mucoperiosteal denudation group.The pattern of bone deposition was the bundle type.Sharpey's fiberswerenotfoundinthemucosaI flapandperiosteum excisiongroups andthedepositions ofpalatalbonewerethelamellartypeasthose in the control group;(3)The rates ofbone deposition in the experimental groups decreased compared with the control group.The rates in different

  1. Proper motions of the Arches cluster with Keck-LGS Adaptive Optics: the first kinematic mass measurement of the Arches

    CERN Document Server

    Clarkson, Will; Morris, Mark; Lu, Jessica; Stolte, Andrea; McCrady, Nate; Do, Tuan; Yelda, Sylvana

    2011-01-01

    We report the first detection of the intrinsic velocity dispersion of the Arches cluster - a young (~2 Myr), massive (~10,000 Solar Mass) starburst cluster located near the Galactic center. This was accomplished using proper motion measurements within the central region of the cluster, obtained with the laser guide star adaptive optics system at Keck Observatory over a 3 year time baseline (2006-2009). This uniform dataset results in proper motion measurements that are improved by a factor ~5 over previous measurements from heterogeneous instruments, yielding internal velocity dispersion estimates 0.15 +/- 0.01 mas/yr, which corresponds to 5.4 +/- 0.4 km/s at a distance of 8.4 kpc. Projecting a simple model for the cluster onto the sky to compare with our proper motion dataset, in conjunction with surface density data, we estimate the total present-day mass of the cluster to be 15,000 (+7400 -6000) Solar masses. The mass in stars observed within a cylinder of radius R=0.4 pc is found to be 9000 (+4000 -3500) ...

  2. Association of Ankle-Brachial Index and Aortic Arch Calcification with Overall and Cardiovascular Mortality in Hemodialysis

    Science.gov (United States)

    Chen, Szu-Chia; Lee, Mei-Yueh; Huang, Jiun-Chi; Shih, Ming-Chen Paul; Chang, Jer-Ming; Chen, Hung-Chun

    2016-01-01

    Peripheral artery occlusive disease and vascular calcification are highly prevalent in hemodialysis (HD) patients, however the association of the combination of ankle-brachial index (ABI) and aortic arch calcification (AoAC) with clinical outcomes in patients undergoing HD is unknown. In this study, we investigated whether the combination of ABI and AoAC is independently associated with overall and cardiovascular mortality in HD patients. The median follow-up period was 5.7 years. Calcification of the aortic arch was assessed by chest X-ray. Forty-seven patients died including 24 due to cardiovascular causes during the follow-up period. The study patients were stratified into four groups according to an ABI 4 or ≤4 according to receiver operating characteristic curve. Those with an ABI  4 (vs. ABI ≥ 0.95 and AoAC score ≤ 4) were associated with overall (hazard ratio [HR], 4.913; 95% confidence interval [CI], 1.932 to 12.497; p = 0.001) and cardiovascular (HR, 3.531; 95% CI, 1.070 to 11.652; p = 0.038) mortality in multivariable analysis. The combination of a low ABI and increased AoAC was associated with increased overall and cardiovascular mortality in patients undergoing HD. PMID:27608939

  3. Accuracy and precision of polyurethane dental arch models fabricated using a three-dimensional subtractive rapid prototyping method with an intraoral scanning technique

    OpenAIRE

    Kim, Jae-Hong; Kim, Ki-Baek; Kim, Woong-Chul; Kim, Ji-Hwan; Kim, Hae-Young

    2014-01-01

    Objective This study aimed to evaluate the accuracy and precision of polyurethane (PUT) dental arch models fabricated using a three-dimensional (3D) subtractive rapid prototyping (RP) method with an intraoral scanning technique by comparing linear measurements obtained from PUT models and conventional plaster models. Methods Ten plaster models were duplicated using a selected standard master model and conventional impression, and 10 PUT models were duplicated using the 3D subtractive RP techn...

  4. Endovascular treatment of aortic arch aneurysms Tratamento endovascular dos aneurismas de arco aórtico

    Directory of Open Access Journals (Sweden)

    Roberto Chiesa

    2008-06-01

    Full Text Available BACKGROUND: Endovascular approach to the aortic arch is an appealing solution for selected patients. OBJECTIVE: To compare the technical and clinical success recorded in the different anatomical settings of endografting for aortic arch disease. METHODS: Between June 1999 and October 2006, among 178 patients treated at our institution for thoracic aorta disease with a stent-graft, the aortic arch was involved in 64 cases. According to the classification proposed by Ishimaru, aortic zone 0 was involved in 14 cases, zone 1 in 12 cases and zone 2 in 38 cases. A hybrid surgical procedure of supra-aortic debranching and revascularization was performed in 37 cases. RESULTS: Zone 0. Proximal neck length: 44±6 mm. Initial clinical success was 78.6%: two deaths (stroke, one type Ia endoleak. At a mean follow-up of 16.4±11 months the midterm clinical success was 85.7%. Zone 1. Proximal neck length: 28±5 mm. Initial clinical success was 66.7%: 0 deaths, four type Ia endoleaks. At a mean follow-up of 16.9±17.2 months the midterm clinical success was 75.0%. Zone 2. Proximal neck length: 30±5 mm. Initial clinical success was 84.2%: two deaths (one cardiac arrest, one multiorgan embolization, three type Ia endoleaks, one case of open conversion. Two cases of delayed transitory paraparesis/paraplegia were observed. At a mean follow-up of 28.0±17.2 months the midterm clinical success was 89.5%. CONCLUSIONS: This study and a literature review demonstrated that hybrid procedure for aortic arch pathology is feasible in selected patients at high risk for conventional surgery. Our experience is still limited by the relatively small sample size. We propose to reserve zone 1 for patients unfit for sternotomy or in cases with aortic neck length > 30 mm following left common carotid artery debranching. We recommend to perform complete aortic rerouting of the aortic arch in cases with lesser comorbidities and shorter aortic neck.CONTEXTO: O tratamento endovascular

  5. Aortic arch thrombectomy in a 2.8 kilogram neonate--a case report and review of the literature.

    Science.gov (United States)

    Omeje, Ikenna; Ram, Awat; Kostolny, Martin

    2013-02-01

    Aortic arch thrombus is a rare occurrence in neonates. In the few described cases, this has mainly been associated with sepsis or early postnatal interventions, such as insertion of umbilical arterial line. We describe a case of occlusive aortic arch thrombus in a neonate who presented with signs of critical coarctation and successfully underwent surgical thrombectomy on deep hypothermic circulatory arrest. We also present a review of the most recently published cases of aortic arch thrombus in neonates and the treatment options employed.

  6. Uinta Arch Project: investigations of uranium potential in Precambrian X and older metasedimentary rocks in the Unita and Wasatch ranges, Utah and Colorado

    Energy Technology Data Exchange (ETDEWEB)

    Graff, P.J.; Sears, J.W.; Holden, G.S.

    1980-06-01

    This study is part of the United States Department of Energy's National Uranium Resource Evaluation Program to understand the geologic setting, amount, and availability of uranium resources within the boundaries of the United States. The systematic study of Precambrian quartz-pebble conglomerates and areas that may contain such conglomerates is an integral part of DOE's resource evaluation program, because deposits of world-wide importance occur in such terrains in Canada and South Africa, and because terrains similar to those producing uranium from quartz-pebble conglomerates exist elsewhere in the United States. Because of the ready availability of Tertiary sandstone and Colorado Plateau-type uranium deposits, large areas of Precambrian rocks in the US have not been fully assessed for uranium potential. Thus, the Uinta Arch Project was undertaken to assess the favorability of Precambrian metasedimentary rocks in northern Utah for deposits of uranium in Precambrian quartz-pebble conglomerates. Rocks of interest to this study are the thick, clastic sequences within the Uinta Arch that are considered to be of Early Proterozoic age. The Uinta Arch area is known to contain rocks which generally fit the lithologic characteristics that are understood to limit the occurrence of Precambrian fossil placers. However, detailed geology of these rocks and their exact fit to the model described for uraniferous conglomerates was not known. The primary goal of the Uinta Arch Project was to determine how well these Precambrian rocks resemble known deposits and to describe the favorability of placer uranium deposits.

  7. The Reinforcement and Reconstruction Design of a Hollow Type Arch Bridge%某空腹式拱桥加固改造设计

    Institute of Scientific and Technical Information of China (English)

    聂立力

    2014-01-01

    拱桥最为我国最常用的一种桥梁形式,其使用时间较长时容易出现病害。本文以一山区空腹式拱桥为例,对其病害情况、加固措施及施工要点等进行了分析与研究,希望能为相关工程提供借鉴。%Arch bridge is the most commonly used bridge form in China, which can easily cause diseases when use for a long time. This article takes a hol ow type arch bridge in a mountain as an example and carries on the analysis and study of the disease situation, the reinforcement measures, and the main points of construction, and hope to provide reference for related projects.

  8. Analysis of the morphology of aortic arch in the cerebral angiography%全脑血管造影术中主动脉弓形态学的分析

    Institute of Scientific and Technical Information of China (English)

    张永力; 刘方军

    2011-01-01

    Objective To analyze the variations and malformations of the aortic arch branches in the cerebral angiography and the changes of aortic arch in patients with different ages. Methods The cere- brai angiography of 774 consecutive patients were included in the study. Angiography of aortic arch and the superselective angiography of its branch arteries were pedormed via femoral artery catheterization. The vari-ations and malformations of aortic arch branches were analyzed. The effects of age on the Myla type, the sharp angles of each aortic arch branches, the brachiocephalic trunk arising from the ascending segment of aortic arch, as well as the vascular tortuos conditions of the aortic arch branches were analyzed. Results ①Aortic arch anomalies were found in 78 cases ( 10.08% ). Of which 68 cases (8.79%) had aortic arch variations;10 cases( 1.29% ) had aortic arch. ②With the increase of age, the proportion of Myla type I aortic arch decreased; the proportions of Myla type II and III aortic arch increased. ③With the increase of age, the inci-dences of the sharp angles of brachiocephalic trunk, left common carotid artery and left subclavian artery increased gradually, and the proportion of brachiocephalic trunk arising from the ascending segment of aortic arch increased. ④With the increase of age, the incidence of non-tortuosity in aortic arch branches decreased gradually, and the incidences of mild, moderate and severe tortuosities increased gradually. ⑤Angiography on each aortic arch branch of 75l cases in this group was successful, and 23 cases failed, in which 5 because of variations of aortic arch, I because of aortic arch malformation, and 17 because of advanced age, sharp singles on aortic arch branches, and severe vascular tortuosity. Conclusion We should fully master the ex-ceptionally complex anatomy and imaging findings of aortic arch and make the cerebral angiography and inter-ventional treatment to be more safe and effective in combination

  9. Analysis on the ultrasonic diagnosis and pathognomonic features of fetal aortic arch anomaly%胎儿主动脉弓异常的超声诊断和畸形特征分析

    Institute of Scientific and Technical Information of China (English)

    陈琮瑛; 李胜利; 文华轩; 毕静茹; 官勇; 陈秀兰; 廖玉媚

    2011-01-01

    Objective: To analyze the ultrasonic features and outcomes of fetal aortic arch anomaly diagnosed by prenatal ultrasonography, understand the pathognomonic features of fetal aortic arch anomaly, improve the diagnosis rate of prenatal ultrasonography for fetal aortic arch anomaly. Methods: 91 fetuses with aortic arch anomaly who received prenatal systematical ultrasonography and were diagnosed definitely in the hospital from 2006 to 2009 were selected as study objects. The prenatal ultrasonic diagnosis, pathognomonic features and outcomes were analyzed. Results: 148 fetuses with aortic arch anomaly were diagnosed by prenatal ultrasonography through conventional heart screening views and special views of aortic arch, one fetus with coarctation of aortic arch was missed diagnosed, 91 fetuses were diagnosed definitely, including 30 fetuses with coarctation of aortic arch, 7 fetuses with interrupted aortic arch (IAA), coarctation of aortic arch and interrupted aortic arch showed small aortic diameter and unbalance of aortic diameter/pulmonary artery diameter ratio in three vessel trachea view (3VTV); 52 fetuses with right -side aortic arch and abnormal aortic branch, 2 fetuses with double aortic arch were also included,the increased distance between aortic arch and arterial duct was showed in 3VTV. 24 fetuses were combined with other severe cardiac anomalies, 7 fetuses were combined with chromosomal abnormalities and 28 fetuses were combined with extracardial anomalies. The diagnosis rate of prenatal ultrasonography of aortic arch anomaly was 92.5% (86/93) . Among 68 fetuses without other severe cardiac anomalies, 42 neonates (61.8%) had good outcomes. Conclusion: Ultrasonography is a main method to diagnose various fetal aortic arch anomalies; small aortic diameter, unbalance of aortic diameter/pulmonary artery diameter ratio and the increased distance between aortic arch and arterial duct in 3VTV are clues for diagnosis of aortic arch anomaly, aortic arch anomaly

  10. L’archéologie médiévale dans et hors l’histoire : retour sur différents usages de la documentation archéologique

    Directory of Open Access Journals (Sweden)

    Mathias Dupuis

    2010-06-01

    Full Text Available L’émergence de l’anthropologique historique a joué un rôle fondamental dans l’essor institutionnel de l’archéologie médiévale française au cours de la seconde moitié du xxe siècle. Cette nouvelle dimension accordée à la discipline archéologique a eu pour corollaire, sinon pour cause, la volonté de prendre en considération l’ensemble des témoignages matériels du passé. L’archéologie est donc entrée progressivement dans le champ de l’histoire médiévale, en produisant un nouveau type de documents historiques. Parallèlement, l’archéologie médiévale s’est également construite hors de l’histoire, à travers ses échanges avec l’histoire de l’art, les sciences naturelles ainsi que sur la base d’une stricte méthodologie. Le présent article revient sur les contradictions d’une discipline tiraillée entre sa position auxiliaire vis-à-vis de l’histoire et ses tentatives d’émancipation en tant que domaine autonome des sciences humaines. La question des différentes définitions et des différents usages de la « documentation archéologique » fera office de fil conducteur dans cette réflexion.The emergence of historical anthropology was a fundamental factor in the institutional development of French medieval archaeology during the second part of 20th century. The consequence, if not the reason, of this new dimension in the study of archeology is a willingness to take into consideration the totality of past material evidences. Archaeology gradually entered into the field of medieval history, producing a new kind of historical documentation. At the same time, medieval archeology itself developed out of history, through its exchange with the history of art or the natural sciences, as well as through the development of a strict methodology. This paper returns to the contradictions of a discipline torn between its secondary position in face of the study of history, and its attempts to define

  11. Experimental investigation of snap-through motion of in-plane MEMS shallow arches under electrostatic excitation

    International Nuclear Information System (INIS)

    We present an experimental investigation for the nonlinear dynamic behaviors of clamped–clamped in-plane MEMS shallow arches when excited by harmonic electrostatic forces. Frequency sweeps are conducted to study the dynamic behaviors in the neighborhoods of the first and third resonance frequencies as well as the super-harmonic resonances. Experimental results show local softening behavior of small oscillations around the first resonance frequency and hardening behavior at the third resonance frequency for small dc and ac loads. Interesting dynamic snap-through cross-well motions are observed experimentally at high voltages for the first time in the micro-scale world. In addition to the dynamic snap-through motion, the MEMS arch exhibits large oscillations of a continuous band of snap-through motion between the super-harmonic resonance regime and the first primary resonance regime. This continuous band is unprecedented experimentally in the micro/macro world, and is promising for a variety of sensing, actuation and communications applications. (paper)

  12. Ambient Vibration Tests of an Arch Dam with Different Reservoir Water Levels: Experimental Results and Comparison with Finite Element Modelling

    Directory of Open Access Journals (Sweden)

    Sergio Vincenzo Calcina

    2014-01-01

    Full Text Available This paper deals with the ambient vibration tests performed in an arch dam in two different working conditions in order to assess the effect produced by two different reservoir water levels on the structural vibration properties. The study consists of an experimental part and a numerical part. The experimental tests were carried out in two different periods of the year, at the beginning of autumn (October 2012 and at the end of winter (March 2013, respectively. The measurements were performed using a fast technique based on asynchronous records of microtremor time-series. In-contact single-station measurements were done by means of one single high resolution triaxial tromometer and two low-frequency seismometers, placed in different points of the structure. The Standard Spectral Ratio method has been used to evaluate the natural frequencies of vibration of the structure. A 3D finite element model of the arch dam-reservoir-foundation system has been developed to verify analytically determined vibration properties, such as natural frequencies and mode shapes, and their changes linked to water level with the experimental results.

  13. Experimental investigation of snap-through motion of in-plane MEMS shallow arches under electrostatic excitation

    KAUST Repository

    Ramini, Abdallah

    2015-12-11

    We present an experimental investigation for the nonlinear dynamic behaviors of clamped–clamped in-plane MEMS shallow arches when excited by harmonic electrostatic forces. Frequency sweeps are conducted to study the dynamic behaviors in the neighborhoods of the first and third resonance frequencies as well as the super-harmonic resonances. Experimental results show local softening behavior of small oscillations around the first resonance frequency and hardening behavior at the third resonance frequency for small dc and ac loads. Interesting dynamic snap-through cross-well motions are observed experimentally at high voltages for the first time in the micro-scale world. In addition to the dynamic snap-through motion, the MEMS arch exhibits large oscillations of a continuous band of snap-through motion between the super-harmonic resonance regime and the first primary resonance regime. This continuous band is unprecedented experimentally in the micro/macro world, and is promising for a variety of sensing, actuation and communications applications.

  14. Experimental investigation of snap-through motion of in-plane MEMS shallow arches under electrostatic excitation

    Science.gov (United States)

    Ramini, Abdallah; Bellaredj, Mohammed L. F.; Hafiz, Md Abdullah Al; Younis, Mohammad I.

    2016-01-01

    We present an experimental investigation for the nonlinear dynamic behaviors of clamped-clamped in-plane MEMS shallow arches when excited by harmonic electrostatic forces. Frequency sweeps are conducted to study the dynamic behaviors in the neighborhoods of the first and third resonance frequencies as well as the super-harmonic resonances. Experimental results show local softening behavior of small oscillations around the first resonance frequency and hardening behavior at the third resonance frequency for small dc and ac loads. Interesting dynamic snap-through cross-well motions are observed experimentally at high voltages for the first time in the micro-scale world. In addition to the dynamic snap-through motion, the MEMS arch exhibits large oscillations of a continuous band of snap-through motion between the super-harmonic resonance regime and the first primary resonance regime. This continuous band is unprecedented experimentally in the micro/macro world, and is promising for a variety of sensing, actuation and communications applications.

  15. Rearfoot alignment and medial longitudinal arch configurations of runners with symptoms and histories of plantar fasciitis

    Directory of Open Access Journals (Sweden)

    Ana Paula Ribeiro

    2011-01-01

    Full Text Available OBJECTIVE: To evaluate and compare rearfoot alignment and medial longitudinal arch index during static postures in runners, with and without symptoms and histories of plantar fasciitis (PF. INTRODUCTION: PF is the third most common injury in runners but, so far, its etiology remains unclear. In the literature, rearfoot misalignment and conformations of the longitudinal plantar arch have been described as risk factors for the development of PF. However, in most of the investigated literature, the results are still controversial, mainly regarding athletic individuals and the effects of pain associated with these injuries. METHODS: Forty-five runners with plantar fasciitis (30 symptomatic and 15 with previous histories of injuries and 60 controls were evaluated. Pain was assessed by a visual analogue scale. The assessment of rearfoot alignment and the calculations of the arch index were performed by digital photographic images. RESULTS: There were observed similarities between the three groups regarding the misalignments of the rearfoot valgus. The medial longitudinal arches were more elevated in the group with symptoms and histories of PF, compared to the control runners. CONCLUSIONS: Runners with symptoms or histories of PF did not differ in rearfoot valgus misalignments, but showed increases in the longitudinal plantar arch during bipedal static stance, regardless of the presence of pain symptoms.

  16. The proper motion of the Arches cluster with Keck Laser-Guide Star Adaptive Optics

    CERN Document Server

    Stolte, Andrea; Morris, Mark; Lu, Jessica R; Brandner, Wolfgang; Matthews, Keith

    2007-01-01

    We present the first measurement of the proper motion of the young, compact Arches cluster near the Galactic center from near-infrared adaptive optics (AO) data taken with the recently commissioned laser-guide star (LGS) at the Keck 10-m telescope. The excellent astrometric accuracy achieved with LGS-AO provides the basis for a detailed comparison with VLT/NAOS-CONICA data taken 4.3 years earlier. Over the 4.3 year baseline, a spatial displacement of the Arches cluster with respect to the field population is measured to be 24.0 +/- 2.2 mas, corresponding to a proper motion of 5.6 +/- 0.5 mas/yr or 212 +/- 20 km/s at a distance of 8 kpc. In combination with the known radial velocity of the cluster, we derive a 3D space motion of 232 +/- 22 km/s of the Arches relative to the field. The large proper motion of the Arches cannot be explained with any of the closed orbital families observed in gas clouds in the bar potential of the inner Galaxy, but would be consistent with the Arches being on a transitional trajec...

  17. The Mono Arch, eastern Sierra region, California: Dynamic topography associated with upper-mantle upwelling?

    Science.gov (United States)

    Jayko, A.S.

    2009-01-01

    A broad, topographic flexure localized east of and over the central and southern Sierra Nevada, herein named the Mono Arch, apparently represents crustal response to lithospheric and/or upper-mantle processes, probably dominated by mantle upwelling within the continental interior associated Pacific-North American plate-boundary deformation. This zone of flexure is identified through comparison between the topographic characteristics of the active Cascade volcanic arc and backarc regions with the analogous former arc and backarc in the Sierra Nevada and eastern Sierra Nevada. Serial topographic profiles measured normal to the modern Cascade backarc reveal an accordance of topographic lows defined by valley floors with an average minimum elevation of ???1400-1500m for over 175km to the southeast. Although the accordance drops in elevation slightly to the south, the modern Cascade backarc region is remarkably level, and is characterized by relief up to ???750m above this baseline elevation. By contrast, serial topographic profiles over the former arc and backarc transitions of the eastern Sierra region exhibit a regional anticlinal warping defined by accordant valley floors and by a late Miocene-early Pliocene erosion surface and associated deposits. The amplitude of this flexure above regionally flat baseline elevations to the east varies spatially along the length of the former Sierran arc, with a maximum of ???1000m centred over the Bridgeport Basin. The total zone of flexure is approximately 350km long N-S and 100km wide E-W, and extends from Indian Wells Valley in the south to the Sonora Pass region in the north. Previous geophysical, petrologic, and geodetic studies suggest that the Mono Arch overlies a zone of active mantle upwelling. This region also represents a zone crustal weakness formerly exploited by the middle-to-late Miocene arc and is presently the locus of seismic and volcanic activities. This seismic zone, which lies east of the Sierra Nevada block

  18. Aortic Arch Atherosclerosis——An Important Potential Source Of Cerebral Embolic Stroke

    Institute of Scientific and Technical Information of China (English)

    Yi Guo; Shao wen Zhang; Si Chen

    2000-01-01

    Background and purpose: Recent years with use of transesophageal echography renew awareness of aortic atherosclerosis. The purpose of this study was to determine the prevalence, clinical significance, and embolic potential of thoracic aortic plaque in patients with cerebral emblism; and further study the correlation aortic plaque with carotid or heart disease. Method: 49 consecutive patients with cerebral embolism was included in this sutdy. We uscd TEE to evaluated potential source of emboli in aortic arch and heart, and duplex in carotid artery. A atherosclerotic lesion of thoracic aorta was defined as normal(O); mild plaque (1); moderate plaque (2); protruding plaque or mobile plaque (3). Result: 31(63%) patients showed evidence of AAA; 7 (14.3%) patients had mild AAA, 9 (18.4%) patients had moderate AAA and 15 (32.7%) patients had severe AAA, In these 15 patients 11 patients neither severe ICAA or embolic heart disease, the AAA may be responsible to the cerebral embolism; 33 patients had internal carotid arterial atherosclerosis(ICAA), 9 patients had embolic heart disease; Age, ICAA had significant correlated with aortic plaque. Conclusion: Aortic atherosclerosis is common in cerebral embolism. Aortic plaque might be not only responsible for some unexplained embolic event, but also for some of the embolic stroke in the group of patient do have carotid artery or heart disease. Age might be important risk factor for the development of atherosclerotic lesion in the thoracic aorta.

  19. Movement of the distal carpal row during narrowing and widening of the carpal arch width.

    Science.gov (United States)

    Gabra, Joseph N; Domalain, Mathieu; Li, Zong-Ming

    2012-10-01

    Change in carpal arch width (CAW) is associated with wrist movement, carpal tunnel release, or therapeutic tunnel manipulation. This study investigated the angular rotations of the distal carpal joints as the CAW was adjusted. The CAW was narrowed and widened by 2 and 4 mm in seven cadaveric specimens while the bone positions were tracked by a marker-based motion capture system. The joints mainly pronated during CAW narrowing and supinated during widening. Ranges of motion about the pronation axis for the hamate-capitate (H-C), capitate-trapezoid (C-Td), and trapezoid-trapezium (Td-Tm) joints were 8.1 ± 2.3 deg, 5.3 ± 1.3 deg, and 5.5 ± 3.5 deg, respectively. Differences between the angular rotations of the joints were found at ΔCAW = -4 mm about the pronation and ulnar-deviation axes. For the pronation axis, angular rotations of the H-C joint were larger than that of the C-Td and Td-Tm joints. Statistical interactions among the factors of joint, rotation axis, and ΔCAW indicated complex joint motion patterns. The complex three-dimensional motion of the bones can be attributed to several anatomical constraints such as bone arrangement, ligament attachments, and articular congruence. The results of this study provide insight into the mechanisms of carpal tunnel adaptations in response to biomechanical alterations of the structural components.

  20. Approach for analyzing the ultimate strength of concrete filled steel tubular arch bridges with stiffening girder

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhi-cheng; XIE Xu; ZHANG He; CHEN Heng-zhi

    2007-01-01

    A convenient approach is proposed for analyzing the ultimate load carrying capacity of concrete filled steel tubular (CFST) arch bridge with stiffening girders. A fiber model beam element is specially used to simulate the stiffening girder and CFST arch rib. The geometric nonlinearity, material nonlinearity, influence of the construction process and the contribution of prestressing reinforcement are all taken into consideration. The accuracy of this method is validated by comparing its results with experimental results. Finally, the ultimate strength of an abnormal CFST arch bridge with stiffening girders isinvestigated and the effect of construction method is discussed. It is concluded that the construction process has little effect on the ultimate strength of the bridge.

  1. Vibration analysis of the Second Saikai Bridge—a concrete filled tubular (CFT) arch bridge

    Science.gov (United States)

    Yoshimura, Mistuhiro; Wu, Qingxiong; Takahashi, Kazuo; Nakamura, Shozo; Furukawa, Kazuyoshi

    2006-02-01

    Concrete-filled steel tubular (CFT) arch bridges have been rapidly developing in China since 1990. Research has focused on the static behavior, thermal stress and erection technique, however, and there has been very little research of natural vibrations and dynamic responses of these bridges. Japan's first CFT arch bridge in highway bridges, the Second Saikai Bridge, is now under construction in Nagasaki Prefecture. Furthermore, this bridge has a pedestrian bridge that is suspended under the girder, which is rare. Therefore, the natural vibration properties are examined, and the influence of pedestrian bridge structure on the natural vibration of main bridge is discussed first. Response analysis under a moving vehicle and pedestrian is carried out, and the response characteristics and response level are clarified. The natural vibrations and responses are compared to those of CFT arch bridges that have been constructed in China. Results show the fine performance of both main bridge and pedestrian bridge of the Second Saikai Bridge.

  2. Research of air-cushion isolation effects on high arch dam reservoir

    Institute of Scientific and Technical Information of China (English)

    Shao-Jie Zhang; Jiang Chen; Yuan-Ze Zhang; Hao-Wu Liu

    2011-01-01

    A three-dimensional (3D) finite element model of air-cushion isolated arch dam is presented with the nonlinear gas-liquid-solid multi-field dynamic coupling effect taken into account.In this model,the displacement formulation in Lagrange method,pressure formulation in Euler method,nonlinear contact model based on Coulomb friction law are applied to the air-cushion,reservoir and contraction joint domain,respectively.The dynamic response of Jinping I arch dam with a height of 305m is analyzed using the seismic records of the Wenchuan Earthquake in 2008.Numerical resuits show that the air-cushion isolation reduces significantly the hydrodynamic pressure as well as the opening width for the contraction joints of high arch dam.

  3. Interdependencies of aortic arch secondary flow patterns, geometry, and age analysed by 4-dimensional phase contrast magnetic resonance imaging at 3 Tesla

    International Nuclear Information System (INIS)

    It was the aim to analyse the impact of age, aortic arch geometry, and size on secondary flow patterns such as helix and vortex flow derived from flow-sensitive magnetic resonance imaging (4D PC-MRI). 62 subjects (age range = 20-80 years) without circumscribed pathologies of the thoracic aorta (ascending aortic (AAo) diameter: 3.2 ± 0.6 cm [range 2.2-5.1]) were examined by 4D PC-MRI after IRB-approval and written informed consent. Blood flow visualisation based on streamlines and time-resolved 3D particle traces was performed. Aortic diameter, shape (gothic, crook-shaped, cubic), angle, and age were correlated with existence and extent of secondary flow patterns (helicity, vortices); statistical modelling was performed. Helical flow was the typical pattern in standard crook-shaped aortic arches. With altered shapes and increasing age, helicity was less common. AAo diameter and age had the highest correlation (r = 0.69 and 0.68, respectively) with number of detected vortices. None of the other arch geometric or demographic variables (for all, P ≥ 0.177) improved statistical modelling. Substantially different secondary flow patterns can be observed in the normal thoracic aorta. Age and the AAo diameter were the parameters correlating best with presence and amount of vortices. Findings underline the importance of age- and geometry-matched control groups for haemodynamic studies. (orig.)

  4. Conceptual Model Summary Report Simulation Framework for Regional Geologic CO2 Storage Along Arches Province of Midwestern United States

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2011-06-30

    A conceptual model was developed for the Arches Province that integrates geologic and hydrologic information on the Eau Claire and Mt. Simon formations into a geocellular model. The conceptual model describes the geologic setting, stratigraphy, geologic structures, hydrologic features, and distribution of key hydraulic parameters. The conceptual model is focused on the Mt. Simon sandstone and Eau Claire formations. The geocellular model depicts the parameters and conditions in a numerical array that may be imported into the numerical simulations of carbon dioxide (CO2) storage. Geophysical well logs, rock samples, drilling logs, geotechnical test results, and reservoir tests were evaluated for a 500,000 km2 study area centered on the Arches Province. The geologic and hydraulic data were integrated into a three-dimensional (3D) grid of porosity and permeability, which are key parameters regarding fluid flow and pressure buildup due to CO2 injection. Permeability data were corrected in locations where reservoir tests have been performed in Mt. Simon injection wells. The final geocellular model covers an area of 600 km by 600 km centered on the Arches Province. The geocellular model includes a total of 24,500,000 cells representing estimated porosity and permeability distribution. CO2 injection scenarios were developed for on-site and regional injection fields at rates of 70 to 140 million metric tons per year.

  5. A novel electrochemical aptasensor based on arch-shape structure of aptamer-complimentary strand conjugate and exonuclease I for sensitive detection of streptomycin.

    Science.gov (United States)

    Mohammad Danesh, Noor; Ramezani, Mohammad; Sarreshtehdar Emrani, Ahmad; Abnous, Khalil; Taghdisi, Seyed Mohammad

    2016-01-15

    Detection and quantitation of antibiotic residues in blood serum and animal foodstuffs are of great significance. In this study, an electrochemical aptasensor was developed for sensitive and selective detection of streptomycin, based on exonuclease I (Exo I), complimentary strand of aptamer (CS), Arch-shape structure of aptamer (Apt)-CS conjugate and gold electrode. The designed aptasensor inherits characteristics of gold including large surface area and high electrochemical conductivity, as well as high sensitivity and selectivity of aptamer toward its target, property of Arch-shape structure of Apt-CS conjugate to act as a gate and barrier for the access of redox probe to the surface of electrode and the function of Exo I as an enzyme which selectively digests the 3'-end of single stranded DNA (ssDNA). In the absence of streptomycin the gate remains closed. Thus, the electrochemical signal is weak. Upon addition of streptomycin, the Apt leaves the CS and binds to streptomycin and the Arch-shape structure is disassembled. Then, Exo I addition leads to a strong electrochemical signal. The designed electrochemical aptasensor exhibited high selectivity toward streptomycin with a limit of detection (LOD) as low as 11.4nM. Moreover, the developed electrochemical aptasensor was successfully used to detect streptomycin in milk and serum with LODs of 14.1 and 15.3nM, respectively.

  6. Treatment effects of mandibular total arch distalization using a ramal plate

    Science.gov (United States)

    Yu, Jonghan; Park, Jae Hyun; Bayome, Mohamed; Kim, Sungkon; Kook, Yoon-Ah; Kim, Yoonji

    2016-01-01

    Objective The purpose of this study was to evaluate treatment effects after distalization of the mandibular dentition using ramal plates through lateral cephalograms. Methods Pre- and post-treatment lateral cephalograms and dental casts of 22 adult patients (11 males and 11 females; mean age, 23.9 ± 5.52 years) who received ramal plates for mandibular molar distalization were analyzed. The treatment effects and amount of distalization of the mandibular molars were calculated and tested for statistical significance. The significance level was set at p < 0.001. Results The mandibular first molar distalization at the crown and root were 2.10 mm (p < 0.001) and 0.81 mm (p = 0.011), respectively. In the evaluation of skeletal variables, there was a significant increase in the Wits appraisal (p < 0.001). In the evaluation of the soft tissue, there was no significant effect on upper lip position, but the lower lips showed a significant retraction of 2.2 mm (p < 0.001). Conclusions The mandibular molars showed a significant amount of distalization accompanied by limited extrusion and mesiobuccal rotation of the crowns. A ramal plate may be a viable device for mandibular total arch distalization in Class III patients who are reluctant to undergo orthognathic surgery. PMID:27478798

  7. Elastic property ratios of a triple-stranded stainless steel arch wire.

    Science.gov (United States)

    Kusy, R P; Dilley, G J

    1984-09-01

    The general elastic property ratio equations for nth-stranded wires are derived and then specified for the case of a triple-stranded arch wire. Several parameters are defined, including the modulus of elasticity (E) and the helical spring (kappa) and bending plane (lambda) shape factors. Thereafter, the elastic property ratios of a wide range of compositional/configurational combinations are determined, using a representative triple-stranded 0.0175 inch (3 X 0.008 inch) stainless steel wire as the base line. These results show that the particular 3 X 0.008 inch wire studied possesses the stiffness of an 0.010 inch stainless steel wire but has at least 20% more strength and range. Furthermore, the stiffness of the 3 X 0.008 inch multistranded wire is similar to an 0.016 inch nickel-titanium wire but only 40% that of an 0.016 inch beta titanium wire. When these elastic property ratios are compared with the previous results reported by Thurow, Burstone, and Kusy, differences are noted which can be explained on the basis of the mechanical property values and/or the geometric modeling assumed.

  8. Seismic damage-cracking analysis of arch dams using different earthquake input mechanisms

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    In this study, a nonlinear model is presented for analysis of damage-cracking behavior in arch dams during strong earthquakes using different seismic input mechanisms. The nonlinear system includes a plastic-damage model for cyclic loading of concrete considering strain softening and a contact boundary model of contraction joint opening. Two different earthquake input mechanisms are used for comparison, including massless foundation input model and viscous-spring boundary model considering radiation damping due to infinite canyon. The results demonstrate that effects of seismic input mechanism and radiation damping on nonlinear response and damage-cracking of the dam are significant. Compared with the results of using massless foundation input model, the damage-cracking region and contraction joint opening are substantially reduced when using viscous-spring boundary model to take into account radiation damping. However, if the damping ratio of the dam is artificially increased to about 10%―15% for massless foundation input model, the joint opening and damage-cracking of the dam are comparable to the results obtained from the viscous-spring boundary model.

  9. Seismic damage-cracking analysis of arch dams usin8 different earthquake input mechanisms

    Institute of Scientific and Technical Information of China (English)

    PAN JianWen; ZHANG ChuHan; WANG JinTing; XU YanJie

    2009-01-01

    In this study, a nonlinear model is presented for analysis of damage-cracking behavior in arch dams during strong earthquakes using different seismic input mechanisms. The nonlinear system includes a plastic-damage model for cyclic loading of concrete considering strain softening and a contact boundary model of contraction joint opening. Two different earthquake input mechanisms are used for comparison, including massless foundation input model and viscous-spring boundary model consid-ering radiation damping due to infinite canyon. The results demonstrate that effects of seismic input mechanism and radiation damping on nonlinear response and damage-cracking of the dam are sig-nificant. Compared with the results of using massless foundation input model, the damage-cracking region and contraction joint opening are substantially reduced when using viscous-spring boundary model to take into account radiation damping. However, if the damping ratio of the dam is artificially increased to about 10%--15% for massiess foundation input model, the joint opening and dam-age-cracking of the dam are comparable to the results obtained from the viscous-spring boundary model.

  10. Clinical, radiological and functional follow-up after surgical decompression of double aortic arch

    Energy Technology Data Exchange (ETDEWEB)

    Berge, Maartje ten; Laag, Johan van der; Ent, Cornelis K. van der [Department of Respiratory Diseases, Wilhelmina Children' s Hospital, Utrecht (Netherlands); Beek, Frederik J.A. [Department of Radiology, Wilhelmina Children' s Hospital, Lundlaan 6, 3584 EA Utrecht (Netherlands)

    2002-08-01

    Heading AbstractBackground. Double aortic arch (DAA) is a congenital vascular anomaly that causes tracheal and oesophageal compression. It requires surgical intervention in patients with severe symptoms.Objective. To evaluate the clinical, radiological and functional follow-up after surgical relief of the compression.Materials and methods. Ten children (seven boys) with DAA were operated on at a mean age of 1.3 years (range 0.2-7.5). At a mean age of 10.1 years (range 5-18 years), a follow-up study was performed that included clinical, radiological and functional parameters.Results. Seven children reported only mild respiratory symptoms and some trouble with swallowing. Preoperative fluoroscopy with spot images showed the mean tracheal diameter at the level of stenosis to be 37{+-}23% of the maximal diameter. At the time of follow-up, this was 70{+-}13%. The mean of the oesophageal diameter was 39{+-}20% preoperatively and 47{+-}16% postoperatively. Maximal expiratory flow volume (MEFV) curves of seven children showed typical characteristics of intrathoracic upper airway obstruction. Mean peak expiratory flow was significantly reduced (77{+-}10% of predicted, P<0.0001). Bronchial hyper-reactivity, tested by methacholine challenge, was found in two patients.Conclusions. There was marked relief of clinical symptoms after surgical decompression of DAA in all patients. In spite of this, radiological narrowing of trachea and oesophagus persisted and lung function results were abnormal at long-term follow-up. (orig.)

  11. Biomechanical implications of excessive endograft protrusion into the aortic arch after thoracic endovascular repair.

    Science.gov (United States)

    Rinaudo, Antonino; Raffa, Giuseppe Maria; Scardulla, Francesco; Pilato, Michele; Scardulla, Cesare; Pasta, Salvatore

    2015-11-01

    Endografts placed in the aorta for thoracic endovascular aortic repair (TEVAR) may determine malappositioning to the lesser curvature of the aortic wall, thus resulting in a devastating complication known as endograft collapse. This premature device failure commonly occurs in young individuals after TEVAR for traumatic aortic injuries as a result of applications outside the physical conditions for which the endograft was designed. In this study, an experimentally-calibrated fluid-structure interaction (FSI) model was developed to assess the hemodynamic and stress/strain distributions acting on the excessive protrusion extension (PE) of endografts deployed in four young patients underwent TEVAR. Endograft infolding was experimentally measured for different hemodynamic scenarios by perfusion testing and then used to numerically calibrate the mechanical behavior of endograft PE. Results evinced that the extent of endograft can severely alter the hemodynamic and structural loads exerted on the endograft PE. Specifically, PE determined a physiological aortic coarctation into the aortic arch characterized by a helical flow in the distal descending aorta. High device displacement and transmural pressure across the stent-graft wall were found for a PE longer than 21 mm. Finally, marked intramural stress and principal strain distributions on the protruded segment of the endograft wall may suggest failure due to material fatigue. These critical parameters may contribute to the endograft collapse observed clinically and can be used to design new devices more suitable for young individuals to be treated with an endoprosthesis for TEVAR of blunt traumatic aortic injuries.

  12. Isogeometric analysis: a powerful numerical tool for the elastic analysis of historical masonry arches

    Science.gov (United States)

    Cazzani, Antonio; Malagù, Marcello; Turco, Emilio

    2016-03-01

    We illustrate a numerical tool for analyzing plane arches such as those frequently used in historical masonry heritage. It is based on a refined elastic mechanical model derived from the isogeometric approach. In particular, geometry and displacements are modeled by means of non-uniform rational B-splines. After a brief introduction, outlining the basic assumptions of this approach and the corresponding modeling choices, several numerical applications to arches, which are typical of masonry structures, show the performance of this novel technique. These are discussed in detail to emphasize the advantage and potential developments of isogeometric analysis in the field of structural analysis of historical masonry buildings with complex geometries.

  13. Properties of some statistics for AR-ARCH model with application to technical analysis

    Science.gov (United States)

    Huang, Xudong; Liu, Wei

    2009-03-01

    In this paper, we investigate some popular technical analysis indexes for AR-ARCH model as real stock market. Under the given conditions, we show that the corresponding statistics are asymptotically stationary and the law of large numbers hold for frequencies of the stock prices falling out normal scope of these technical analysis indexes under AR-ARCH, and give the rate of convergence in the case of nonstationary initial values, which give a mathematical rationale for these methods of technical analysis in supervising the security trends.

  14. Neonate with VACTERL Association and a Branchial Arch Anomaly without Hydrocephalus.

    Science.gov (United States)

    Velazquez, Danitza; Pereira, Elaine; Havranek, Thomas

    2016-03-01

    VACTERL (vertebral anomalies, anal atresia, cardiac defect, tracheoesophageal fistula, renal anomaly, limb anomalies) is an association of anomalies with a wide spectrum of phenotypic expression. While the majority of cases are sporadic, there is evidence of an inherited component in a small number of patients as well as the potential influence of nongenetic risk factors (maternal diabetes mellitus). Presence of hydrocephalus has been reported in VACTERL patients (VACTERL-H) in the past, with some displaying branchial arch anomalies. We report the unique case of an infant of diabetic mother with VACTERL association and a branchial arch anomaly-in the absence of hydrocephalus.

  15. Mycotic aneurysm of the aortic arch presenting with left vocal cord palsy.

    Science.gov (United States)

    Tokmaji, George; Gosev, Igor; Kumamaru, Kanako Kunishima; Bolman, Ralph Morton

    2013-07-01

    We report a case of a 71-year-old man with a mycotic aneurysm of the aortic arch who presented with progressive hoarseness. Three weeks prior to this event the patient was admitted to an outside hospital in septic condition and was diagnosed with a mycotic abdominal aortic aneurysm. Resection of the infected abdominal aortic aneurysm with right axillofemoral and femoral-femoral bypass grafts was performed and the patient was discharged home on intravenous antibiotics. At our institution, the aortic arch aneurysm was treated with extensive debridement and replaced with a Dacron prosthesis under circulatory arrest with antegrade cerebral perfusion through the axillofemoral bypass. PMID:23816081

  16. Endovascular Treatment for Proximal Anastomotic Pseudoaneurysm after Total Arch Replacement in Behcet's Disease.

    Science.gov (United States)

    Sakata, Tomoki; Ueda, Hideki; Watanabe, Michiko; Kohno, Hiroki; Tamura, Yusaku; Abe, Shinichiro; Inage, Yuichi; Ikeuchi, Hiroki; Kanda, Tomoyoshi; Fujii, Masahiko; Matsumiya, Goro

    2016-07-01

    A 17-year-old patient underwent total arch replacement for aortic arch aneurysm due to vascular Behcet's disease (BD). Follow-up computed tomography, performed 6 months after the operation, demonstrated pseudoaneurysm formation at the proximal anastomotic site. We performed endovascular treatment and used a short stent graft that was originally designed for abdominal aortic aneurysm. To avoid the occlusion of the coronary or brachiocephalic artery (BCA) due to stent graft migration, we used right ventricular rapid pacing and BCA ballooning. Thus, we believe that endovascular treatment can be used for anastomotic complications in the ascending aorta after open surgery for connective tissue disorders including BD. PMID:27174345

  17. Mathematical Modeling and Numerical Analysis of Thermal Distribution in Arch Dams considering Solar Radiation Effect

    Directory of Open Access Journals (Sweden)

    H. Mirzabozorg

    2014-01-01

    Full Text Available The effect of solar radiation on thermal distribution in thin high arch dams is investigated. The differential equation governing thermal behavior of mass concrete in three-dimensional space is solved applying appropriate boundary conditions. Solar radiation is implemented considering the dam face direction relative to the sun, the slop relative to horizon, the region cloud cover, and the surrounding topography. It has been observed that solar radiation changes the surface temperature drastically and leads to nonuniform temperature distribution. Solar radiation effects should be considered in thermal transient analysis of thin arch dams.

  18. 斜靠式系杆拱桥拱肋安装技术%The Installation Technology of Arch Ribs of Leaning Type CFST Arch Bridge

    Institute of Scientific and Technical Information of China (English)

    柳明佳

    2011-01-01

    通过南通新开北路通启运河大桥施工实例,介绍了斜靠式系杆拱桥的拱肋安装施工技术,并对影响拱肋安装精度的因素进行了分析,对如何控制做了简述。%This article introduces the installation and construction technology of arch ribs of leaning-type CFST arch bridge with the construction example of Nantong Tongqi canal bridge on North Xinkai road. And it also analyzes the factors of the accuracy of rib installation and makes a brief introduction of how to control.

  19. Comparative study of clinic effects of segmental archs and mini-implants for orthodontic anchorage on orthodontic canine distalization%片段弓与微种植体支抗拉尖牙向远中的临床应用对比研究

    Institute of Scientific and Technical Information of China (English)

    徐晓静; 沈云娟; 秦燕军

    2012-01-01

    Objective To compare the clinic effects of segmental archs and mini-implants for orthodontic anchorage on orthodontic canine distalization. Methods 60 cases of dental crowding, whose four first premolars were extracted and canine distalization was needed according to the treatment protocol, were randomly divided into 2 groups. Mini-implants were used in the cases in experimental group as orthodontic anchorage to move canine distally, and segmental archs were used in the control cases. The distances of canine dis-talizalion and the angles of anchorage molar inclination in 60 cases were measured and compared. Results The mean velocity of canine distalizalion in the experimental group was (1.428 ±0.072) mm/month,which was faster than(l. 137 ±0.081)mm/month in the control group. The degree of molar inclination (1.27 ±0.18) in the experimental group was less than that in the control group (1.91 ±0.13). Statistic analysis showed that there were significant differences. Conclusions The mini-implants for orthodontic anchorage can move the canine faster and control the anchorage molar better than the segmental arch.%目的 比较片段弓技术和微种植体支抗在拉尖牙向远中的临床应用效果.方法 60例牙列拥挤,双侧对称拔除第一前磨牙且需将尖牙拉向远中的患者,随机分为2组,试验组尖牙远移时应用微种植体作为支抗,对照组则使用片段弓技术远移尖牙,测量尖牙向远中移动的距离以及磨牙近中倾斜的程度.结果 试验组尖牙移动的速率为(1.428±0.072)mm/月,快于对照组(1.137±0.081)mm/月;试验组磨牙近中倾斜程度为(1.27±0.18)°,小于对照组(1.91±0.13)°.经统计学检验差异均有显著性(P<0.05).结论 使用微种植体支抗拉尖牙向远中在牙齿移动速率以及控制磨牙近中倾斜等方面优于片段弓技术.

  20. Estudo comparativo das dimensões transversais dos arcos dentários entre jovens com oclusão normal e má oclusão de Classe II, 1ª divisão A comparative study of arch widths of white Brazilians with normal occlusion and Class II, Division 1, malocclusion

    Directory of Open Access Journals (Sweden)

    Rejman Roberto

    2006-08-01

    Full Text Available OBJETIVO: avaliar as possíveis diferenças nas dimensões transversais dos arcos dentários superiores e inferiores entre jovens com oclusão normal e má oclusão de Classe II, 1ª divisão. METODOLOGIA: foram avaliados 170 pares de modelos em gesso de jovens brasileiros leucodermas, com dentadura permanente, sendo 76 com oclusão normal (41 do gênero feminino e 35 do masculino e média de idade de 13 anos e 6 meses e 94 com má oclusão de Classe II, 1ª divisão (58 do gênero feminino e 36 do masculino e média de idade de 13 anos e 9 meses. Este grupo com má oclusão foi dividido em duas categorias: Classe II sem apinhamento e Classe II com apinhamento. Compararam-se as distâncias intercaninos, interprimeiros pré-molares e intermolares, em ambos os arcos dentários. RESULTADOS: em relação ao grupo com oclusão normal, os jovens do gênero masculino evidenciaram as seguintes diferenças estatisticamente significantes: 1 distância intercaninos inferiores maior para o grupo com Classe II sem apinhamento; 2 distância interprimeiros pré-molares superiores menor para o grupo com Classe II sem apinhamento e 3 distâncias interprimeiros pré-molares e intermolares, superiores e inferiores, menores para o grupo com Classe II com apinhamento. Por sua vez, o gênero feminino evidenciou: 1 distâncias interprimeiros pré-molares e intermolares superiores menores para o grupo com Classe II sem apinhamento e 2 distâncias interprimeiros pré-molares e intermolares, superiores e inferiores, menores para o grupo com Classe II com apinhamento. CONCLUSÃO: de um modo geral, os jovens com má oclusão de Classe II, 1ª divisão, apresentaram uma tendência para deficiência transversal posterior dos arcos dentários, principalmente no grupo com apinhamento.AIM: to evaluate possible differences of the upper and lower dental arches widths among youths with normal occlusion and Class II, division 1, malocclusion. METHODS: the evaluation was conducted

  1. Treatment of flaring of the costal arch after the minimally invasive pectus excavatum repair (Nuss procedure) in children.

    NARCIS (Netherlands)

    Bosgraaf, R.P.; Aronson, D.C.

    2010-01-01

    Flaring of the costal arch may be part of the pectus excavatum deformity. This aspect will in rare cases be even worsen after the Nuss repair. This remaining deformity can be treated with a minimal subperichondral partial resection of the costal arch cartilage. In 5 patients, this additional techniq

  2. Treatment of flaring of the costal arch after the minimally invasive pectus excavatum repair (Nuss procedure) in children

    NARCIS (Netherlands)

    R.P. Bosgraaf; D.C. Aronson

    2010-01-01

    Flaring of the costal arch may be part of the pectus excavatum deformity. This aspect will in rare cases be even worsen after the Nuss repair. This remaining deformity can be treated with a minimal subperichondral partial resection of the costal arch cartilage. In 5 patients, this additional techniq

  3. Aortic Arch Vessel Anomalies Associated with Persistent Trigeminal Artery: (Report of a Case

    Directory of Open Access Journals (Sweden)

    M. Lotfi

    2008-01-01

    Full Text Available Introduction: Developmental anomalies of the aortic arch vessels are well described entities. Persistent trigeminal artery (PTA is the most common type of the four anomalous carotid-basilar anastomoses, and is due to abnormal persistence of what are normal transient communications between the embryonic forebrain and hindbrain arterial systems. Herein we report a previously undescribed variant consisting of coexistence of the PTA, truncus bicaroticus, and di-rect origin of left vertebral artery from aortic arch. "nCase Presentation: A 46 year-old man was admitted in the Namazi hospital with severe nausea, vomiting, severe headache, and decreased level of conscious-ness. Computed tomography scan revealed intraven-tricular hemorrhage with no evidence of subarach-noid hemorrhage. The patient was referred for four-vessel cerebral arteriography to evaluate the entire cerebral vascular anatomy. Arch aortography demon-strated the right subclavian artery as the first branch of the arch. The left vertebral artery arose directly from the arch as the second branch. The third branch consisted of a common trunk giving rise to the right and left common carotid arteries (Truncus Bicaroti-cus. The left subclavian artery arose as the final branch of the aortic arch. Selective angiography con-firmed that left vertebral artery did not arise from the left subclavian artery. Left vertebral artery angiogra-phy revealed a persistent trigeminal artery, with fill-ing of left internal carotid artery and its branches. No aneurysm or any other vascular abnormality was de-tected in this patient. The patient was subsequently managed by evacuation of IVH and ventriculostomy."nDiscussion: The usual configuration of three branches from the aortic arch is found in 60-80% of popula-tion. The left vertebral artery normally originate along the superior portion of the left subclavian ar-tery. However, this artery is subject to a number of variations; among all; the most common

  4. An Experimental Investigation of the Dynamic Behavior of an In-Plane MEMS Shallow Arch Under Electrostatic Excitation

    KAUST Repository

    Ramini, Abdallah

    2016-01-20

    We present experimental investigation of the nonlinear dynamics of a clamped-clamped in-plane MEMS shallow arch when excited by an electrostatic force. We explore the dynamic behaviors of the in-plane motion of the shallow arches via frequency sweeps in the neighborhood of the first resonance frequency. The shallow arch response is video microscopy recorded and analyzed by means of digital imaging. The experimental data show local softening behavior for small DC and AC loads. For high voltages, the experimental investigation reveals interesting dynamics, where the arch exhibits a dynamic snap-Through behavior. These attractive experimental results verify the previously reported complex behavior of in-plane MEMS arches and show promising results to implement these structures for variety of sensing and actuation applications. © Copyright 2015 by ASME.

  5. Susceptibility to corrosion of laser welding composite arch wire in artificial saliva of salivary amylase and pancreatic amylase.

    Science.gov (United States)

    Zhang, Chao; Liu, Jiming; Yu, Wenwen; Sun, Daqian; Sun, Xinhua

    2015-10-01

    In this study, laser-welded composite arch wire (CAW) with a copper interlayer was exposed to artificial saliva containing salivary amylase or pancreatic amylase, and the resultant corrosion behavior was studied. The purpose was to determine the mechanisms by which salivary amylase and pancreatic amylase contribute to corrosion. The effects of amylase on the electrochemical resistance of CAW were tested by potentiodynamic polarization measurements. The dissolved corrosion products were determined by ICP-OES, and the surfaces were analyzed by SEM, AFM and EDS. The results showed that both exposure to salivary amylase and pancreatic amylase significantly improved the corrosion resistance of CAW. Even isozyme could have different influences on the alloy surface. When performing in vitro research of materials to be used in oral cavity, the effect of α-amylase should be taken into account since a simple saline solution does not entirely simulate the physiological situation. PMID:26117761

  6. Susceptibility to corrosion of laser welding composite arch wire in artificial saliva of salivary amylase and pancreatic amylase.

    Science.gov (United States)

    Zhang, Chao; Liu, Jiming; Yu, Wenwen; Sun, Daqian; Sun, Xinhua

    2015-10-01

    In this study, laser-welded composite arch wire (CAW) with a copper interlayer was exposed to artificial saliva containing salivary amylase or pancreatic amylase, and the resultant corrosion behavior was studied. The purpose was to determine the mechanisms by which salivary amylase and pancreatic amylase contribute to corrosion. The effects of amylase on the electrochemical resistance of CAW were tested by potentiodynamic polarization measurements. The dissolved corrosion products were determined by ICP-OES, and the surfaces were analyzed by SEM, AFM and EDS. The results showed that both exposure to salivary amylase and pancreatic amylase significantly improved the corrosion resistance of CAW. Even isozyme could have different influences on the alloy surface. When performing in vitro research of materials to be used in oral cavity, the effect of α-amylase should be taken into account since a simple saline solution does not entirely simulate the physiological situation.

  7. A quadrant tray and bite registration as an alternative to dual-arch impressions for fixed prosthetics: a clinical and dental laboratory technique.

    Science.gov (United States)

    Hammond, Barry D; Myers, Michael L; Haywood, Van B

    2011-01-01

    To perform fixed prosthodontic procedures, dentists take a full-arch or quadrant impression and articulate the casts. The dual-arch impression technique is a popular quadrant technique for crown fabrication. The technique described in this article, which uses a quadrant impression and separate interocclusal record, offers several advantages over the traditional dual-arch method.

  8. 下套拱加固石拱桥复合拱圈极限承载力研究%Research on ultimate load -carrying capacity of composite arch ring ofstone arch bridge reinforced by concrete arch -lifted method

    Institute of Scientific and Technical Information of China (English)

    孙潮; 刘明; 陈宝春; 吴庆雄

    2012-01-01

    The composite arch ring formed by soffitting method for stone arch consists four materials, i.e. , stone, mortar, concrete and steel bars. It is a secondary loaded structure, so its behavior is complicated. A finite element method (FEM) to calculate the ultimate load -carrying capacity of the composite arch ring is proposed by using both smeared model and discrete model. The computing results from FEM agrees well with the test results, which indicates that the behavior of the composite arch ring can be depicted well by the proposed FEM. Analysis of a real engineering have been done by using this FEM. Analysis results shows that under the half span distributed load and quarter point load, the failure mode of the composite arch ring is a four - hinges mechanism. The load reaches 77.9% of the ultimate load when the second hinge appears. Ultimate load - carrying capacity decreases with the increase of the ratio of concentrated live load to the total live load, also increases with the increase of the thickness of reinforcement layer and reinforcement ratio. The concrete strength has a little influence on the ultimate load - carrying capacity of composite arch ring, so high strength concrete is not necessary to be adopted in this method.%下套拱加固石拱桥形成的复合拱圈由石块、砂浆、混凝土和钢筋四种材料组成,而且属于二次受力结构,受力复杂.采用分离模型和整体连续体模型相结合的方法,提出复合拱圈的极限承载力有限元计算方法.有限元计算结果与试验结果吻合良好,表明有限元计算方法能够反映复合拱圈的受力性能.应用该方法,对某实桥进行了分析,结果表明,复合拱圈在半跨均布活载和L/4集中活载联合作用下的破坏模式为四铰破坏,第二个铰出现时荷载已达极限荷载的77.9%.复合拱圈的极限承载力随着集中活载占总活载的比例的增大而减小,随加固层厚度和配筋率的增大而增大.

  9. C1 anterior arch preservation in transnasal odontoidectomy using three-dimensional endoscope: A case report

    Directory of Open Access Journals (Sweden)

    Francesco Zenga

    2015-01-01

    Conclusions: The stereoscopic perception augmented the precision of the surgical gesture in the deep field. The importance of a 3D view relates to the depth of field, which a two-dimensional endoscopy cannot provide. This affects the preservation of the C1 anterior arch because of the presence of critical structures that are exposed to potential damage if not displayed.

  10. Double aortic arch as a source of airway obstruction in a child

    Directory of Open Access Journals (Sweden)

    Sambhunath Das

    2015-01-01

    Full Text Available Double aortic arch (DAA is a congenital vascular anomaly. The diagnosis was difficult till the child was symptomatic, and other causes were ruled out. We present the interesting images of a child of respiratory distress because of tracheal compression from DAA.

  11. An Automatic Method for Geometric Segmentation of Masonry Arch Bridges for Structural Engineering Purposes

    Science.gov (United States)

    Riveiro, B.; DeJong, M.; Conde, B.

    2016-06-01

    Despite the tremendous advantages of the laser scanning technology for the geometric characterization of built constructions, there are important limitations preventing more widespread implementation in the structural engineering domain. Even though the technology provides extensive and accurate information to perform structural assessment and health monitoring, many people are resistant to the technology due to the processing times involved. Thus, new methods that can automatically process LiDAR data and subsequently provide an automatic and organized interpretation are required. This paper presents a new method for fully automated point cloud segmentation of masonry arch bridges. The method efficiently creates segmented, spatially related and organized point clouds, which each contain the relevant geometric data for a particular component (pier, arch, spandrel wall, etc.) of the structure. The segmentation procedure comprises a heuristic approach for the separation of different vertical walls, and later image processing tools adapted to voxel structures allows the efficient segmentation of the main structural elements of the bridge. The proposed methodology provides the essential processed data required for structural assessment of masonry arch bridges based on geometric anomalies. The method is validated using a representative sample of masonry arch bridges in Spain.

  12. Right-sided aortic arch with anomalous origin of the left subclavian artery: Case report

    Directory of Open Access Journals (Sweden)

    Vučurević Goran

    2011-01-01

    Full Text Available Introduction. A right-sided aortic arch is a rare congenital defect of the aorta with incidence of 0.05% to 0.1% reported in published series. Usually it is associated with congenital heart anomalies and esophageal and tracheal compression symptoms. We present a case of a right-sided aortic arch of anomalous left subclavian artery origin, accidentally revealed during multislice CT (MSCT supraaortic branches angiography. Case Outline. A 53-year-old female patient was examined at the Outpatients’ Unit of the Vascular Surgery University Clinic for vertigo, occasional dizziness and difficulty with swallowing. Physical examination revealed a murmur of the left supraclavicular space, with 15 mmHg lower rate of arterial tension on the left arm. Ultrasound of carotid arteries revealed 60% stenosis of the left subclavian artery and bilateral internal carotid artery elongation. MSCT angiography revealed a right-sided aortic arch with aberrant separation of the left subclavian artery that was narrowed 50%, while internal carotid arteries were marginally elongated. There was no need for surgical treatment or percutaneous interventions, so that conservative treatment was indicated. Conclusion. A right-sided aortic arch is a very rare anomaly of the location and branching of the aorta. Multislice CT angiography is of great importance in the diagnostics of this rare disease.

  13. Three-Dimensional Aquila Rift: Magnetized HI Arch Anchored by Molecular Complex

    CERN Document Server

    Sofue, Yoshiaki

    2016-01-01

    Three dimensional structure of the Aquila Rift of magnetized neutral gas is investigated by analyzing HI and CO line data. The projected distance on the Galactic plane of the HI arch of the Rift is ~250 pc from the Sun. The HI arch emerges at l~ 30 deg, reaches to altitudes as high as ~ 500 pc above the plane at l~ 350deg, and returns to the disk at l~270 deg. The extent of arch at positive latitudes is ~1 kpc and radius is ~100 pc. The eastern root is associated with the giant molecular cloud complex, which is the main body of the optically defined Aquila Rift. The HI and molecular masses of the Rift are estimated to be M_HI~1.4x10^5Msun and M_H2 ~3x10^5 Msun. Gravitational energies to lift the gases to their heights are E_grav: HI ~1.4x10^51 and E_grav: H_2 ~0.3x10^51 erg, respectively. Magnetic field is aligned along the HI arch of the Rift, and the strength is measured to be B~10 microG using Faraday rotation measures of extragalactic radio sources. The magnetic energy is estimated to be E_mag~1.2x10^51 e...

  14. Prenatal diagnosis of the rare association of common arterial trunk and double aortic arch

    OpenAIRE

    Rock, Andrea; Eltayeb, Osama; Camarda, Joseph; Gotteiner, Nina

    2016-01-01

    Key Clinical Message Common arterial trunk with associated double aortic arch is a very rare constellation of congenital heart disease. Prenatal diagnosis allows for surgical repair prior to development of respiratory morbidity, which is otherwise described in all cases with this association.

  15. The impact of foot arch height on quality of life in 6-12 year olds

    Directory of Open Access Journals (Sweden)

    Daniel López López

    2015-01-01

    Full Text Available Objective:To determine whether arch height has an effect on the health-related quality of life of schoolchildren.Methods:One hundred and thirteen schoolchildren attended an out-patient centre where self-reported data were recorded, their feet were classified into one of three groups according to their arch index (high, normal or low and the scores obtained from the Foot Health Status Questionnaire (FHSQ - Spanish version were compared.Results:The groups with high, low and normal arch recorded lower scores in Section One for the general foot health and footwear domains and higher scores in foot pain and foot function. In Section Two they obtained lower scores in general health and higher scores in physical activity, social capacity and vigour.Conclusions:Comparison of the scores obtained reveals that arch height has a negative impact on quality of life. Given the limited extent of available evidence in respect of the aetiology and treatment of foot diseases and deformities, these findings reveal the need to implement programmes to promote foot health and carry out further research into this commonly occurring disabling condition.

  16. ENTRAINMENT OF THE BREATHING RHYTHM OF THE CARP BY IMPOSED OSCILLATION OF THE GILL ARCHES

    NARCIS (Netherlands)

    DEGRAAF, PJF; ROBERTS, BL

    1991-01-01

    Artificial oscillation imposed onto the gill arches could modify the respiratory rhythm in the carp Cyprinus carpio. The degree of modification depended upon the frequency and amplitude of the applied movement. Oscillation at frequencies close to the spontaneous respiratory rhythm and at amplitudes

  17. Ross Errilly Franciscan Friary, north chancel wall, tomb niche, jamb, arch and hood moulding

    OpenAIRE

    O'Donovan, Danielle

    2002-01-01

    Moulding of tomb niche, jamb and arch moulding from intrados comprises: hollow chamfer, right-angled rebate, hollow chamfer, quadrant. Hood comprises frontal fillet, hollow chamfer. In design, the tomb niche looks like those from Quin and Ennis, which are related to the Limerick/Kerry examples. The moulding looks very like that of the west door.

  18. [Antegrade unilateral perfusion of the brain through the brachiocephalic trunk in operations on the aortic arch].

    Science.gov (United States)

    Kozlov, B N; Panfilov, D S; Kuznetsov, M S; Ponomarenko, I V; Nasrashvili, G G; Shipulin, V M

    2016-01-01

    Presented herein is a technique of unilateral antegrade perfusion of the brain in operations on the aortic arch. The method makes it possible to perform both systemic artificial circulation and adequate physiological perfusion of the brain, promoting minimization of the number of neurological complications. PMID:27100557

  19. Cephalic arch stenosis in autogenous brachiocephalic hemodialysis fistulas: results of cutting balloon angioplasty

    DEFF Research Database (Denmark)

    Heerwagen, Søren Thorup; Lönn, Lars; Schroeder, Torben V;

    2010-01-01

    Cephalic arch stenosis is a known cause of hemodialysis access failure in patients with brachiocephalic fistulas (BCFs). Outcomes of endovascular treatment are affected by resistance of the stenosis to balloon dilation, a high vein rupture rate and the development of early restenosis. The purpose...

  20. Truncus arteriosus with aortic arch interruption: cardiovascular magnetic resonance findings in the unrepaired adult

    OpenAIRE

    Cook Stephen C; Thavendiranathan Paaladinesh; Arruda Janine; Verhaert David; Raman Subha V

    2010-01-01

    Abstract Truncus arteriosus (TA) is a rare congenital condition defined as a single arterial vessel arising from the heart that gives origin to the systemic, pulmonary and coronary circulations. We discuss the unique case of a 28 year-old female patient with unrepaired TA and interruption of the aortic arch who underwent cardiovascular magnetic resonance (CMR).