5,592 results on '"Clockwise"'
Search Results
2. Left Ventricular "Longitudinal Rotation" and Conduction Abnormalities—A New Outlook on Dyssynchrony.
- Author
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Marai, Ibrahim, Haddad, Rabea, Andria, Nizar, Kinany, Wadi, Hazanov, Yevgeni, Kleinberg, Bruce M., Birati, Edo, and Carasso, Shemy
- Subjects
- *
BUNDLE-branch block , *SPECKLE tracking echocardiography , *ROTATIONAL motion , *MITRAL valve - Abstract
Background: The complete left bundle branch block (CLBBB) results in ventricular dyssynchrony and a reduction in systolic and diastolic efficiency. We noticed a distinct clockwise rotation of the left ventricle (LV) in patients with CLBBB ("longitudinal rotation"). Aim: The aim of this study was to quantify the "longitudinal rotation" of the LV in patients with CLBBB in comparison to patients with normal conduction or complete right bundle branch block (CRBBB). Methods: Sixty consecutive patients with normal QRS, CRBBB, or CLBBB were included. Stored raw data DICOM 2D apical-4 chambers view images cine clips were analyzed using EchoPac plugin version 203 (GE Vingmed Ultrasound AS, Horten, Norway). In EchoPac–Q-Analysis, 2D strain application was selected. Instead of apical view algorithms, the SAX-MV (short axis—mitral valve level) algorithm was selected for analysis. A closed loop endocardial contour was drawn to initiate the analysis. The "posterior" segment (representing the mitral valve) was excluded before finalizing the analysis. Longitudinal rotation direction, peak angle, and time-to-peak rotation were recorded. Results: All patients with CLBBB (n = 21) had clockwise longitudinal rotation with mean four chamber peak rotation angle of −3.9 ± 2.4°. This rotation is significantly larger than in patients with normal QRS (−1.4 ± 3°, p = 0.005) and CRBBB (0.1 ± 2.2°, p = 0.00001). Clockwise rotation was found to be correlated to QRS duration in patients with the non-RBBB pattern. The angle of rotation was not associated with a lower ejection fraction or the presence of regional wall abnormalities. Conclusions: Significant clockwise longitudinal rotation was found in CLBBB patients compared to normal QRS or CRBBB patients using speckle-tracking echocardiography. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
- View/download PDF
3. The inferocentral whorl region and its directional patterns in the corneal sub-basal nerve plexus: A review.
- Author
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Badian, Reza A. and Lagali, Neil
- Subjects
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CORNEA , *NERVES , *DIABETIC neuropathies , *NERVE fibers , *CONFOCAL microscopy - Abstract
There has been a growing application of in vivo confocal microscopy (IVCM) in the examination of corneal microstructure, including different corneal layers and corneal nerve fibers in health and in pathological conditions. Corneal nerves forming the sub-basal nerve plexus (SBNP) beneath the corneal basal epithelial cell layer in particular have been intensively researched in health and disease as a marker for corneal neurophysioanatomical and degenerative changes. One intriguing feature in the SBNP that is found inferior to the corneal apex, is a whorl-like pattern (or vortex) of nerves, which represents an anatomical landmark. Evidence has indicated that the architecture of this 'whorl region' is dynamic, changing with time in healthy individuals but also in disease conditions such as in diabetic neuropathy and keratoconus. This review summarizes the known information regarding the characteristics and significance of the whorl region of nerves in the corneal SBNP, as a potential area of high relevance for future disease monitoring and diagnostics. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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4. The Sawtooth Rhythm: Atrial Flutter
- Author
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Gomes, J. Anthony and Gomes, J. Anthony
- Published
- 2021
- Full Text
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5. CALIBRATION OF REFERENCE TORQUE TRANSDUCER IN ONE DIRECTION AND USE OF ITS CUBIC COEFFICIENTS IN BOTH DIRECTIONS WITH IMPROVED INTERPOLATION ERROR.
- Author
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Khaled, K. M. and Osman, Seif M.
- Subjects
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TORQUE , *INTERPOLATION , *CUBIC curves , *CALIBRATION , *CURVE fitting , *TRANSDUCERS , *INTERPOLATION algorithms , *TORQUE control - Abstract
The current research work presents an investigation into use of the fitting coefficients resulting from the cubic curve fitting of the torque transducer calibration results in one direction to calculate the actual torque in the other torque direction with two methods: one is direct substitution with the nominal torque which gives a propagated linear relative interpolation error and the other is changing the sign of the second coefficient in the cubic function when using in the other torque direction. This proposed modification improves the absolute relative interpolation error by 5 to 16 times in the clockwise and counterclockwise directions based on the torque transducer's classification. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
6. Atrial Flutter
- Author
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Gomes, J. Anthony and Gomes, J. Anthony
- Published
- 2020
- Full Text
- View/download PDF
7. A Method for Minimizing Rotational Errors of Implant Prostheses.
- Author
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Hyeonjong Lee, Kung-Rock Kwon, Janghyun Paek, Ahran Pae, and Kwantae Noh
- Subjects
DENTAL implant complications ,ROTATIONAL motion ,DENTAL impression materials ,ERRORS ,DENTAL resins ,PREVENTION ,DENTAL impressions ,DENTAL implants ,MEDICAL errors ,DATA analysis software ,DESCRIPTIVE statistics - Abstract
Purpose: Rotational errors of implants can occur during two stages: when connecting impression copings with implants, and when connecting impression copings with analogs. The aim of this study was to determine ways to minimize these rotational errors. Materials and Methods: Three types of implants were prepared: a tissue-level implant with an internal octagon 8-degree Morse taper connection, a bone-level implant with an internal hex 11-degree Morse taper connection, and a bone-level implant with an external hex connection. Each complex (n = 10 per group) was composed of an implant, an impression coping, and an analog. Implants were embedded in resin blocks and connected with corresponding impression copings. Analogs that reproduced the position of the implants were created by means of a custom-made transfer jig, and rotational errors were measured between implants and analogs. Impression copings and analogs were connected by means of four methods: The impression coping was connected to the implant in a clockwise (CW) or a counterclockwise (CCW) direction before tightening, and the analogs were then connected with impression copings and tightened using a hemostat (Hs) or by hand (Hd). Results: The CW-Hs and CCW-Hd groups exhibited low rotational error (mean ± standard deviation 0.11 ± 0.21 and 0.19 ± 0.34 degrees, respectively), whereas the CW-Hd and CCW-Hs groups exhibited high rotational error (-1.80 ± 0.67 and 2.07 ± 0.75, respectively) in different directions. A strong association was observed between the tightening method and rotational error, and a weak association was observed between the connection type and rotational error. Conclusion: The CW-Hs method was found to be the most suitable for minimizing rotational error between implants and analogs. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
8. Left Ventricular 'Longitudinal Rotation' and Conduction Abnormalities—A New Outlook on Dyssynchrony
- Author
-
Ibrahim Marai, Rabea Haddad, Nizar Andria, Wadi Kinany, Yevgeni Hazanov, Bruce M. Kleinberg, Edo Birati, and Shemy Carasso
- Subjects
CLBBB ,clockwise ,longitudinal ,rotation ,Medicine - Abstract
Background: The complete left bundle branch block (CLBBB) results in ventricular dyssynchrony and a reduction in systolic and diastolic efficiency. We noticed a distinct clockwise rotation of the left ventricle (LV) in patients with CLBBB (“longitudinal rotation”). Aim: The aim of this study was to quantify the “longitudinal rotation” of the LV in patients with CLBBB in comparison to patients with normal conduction or complete right bundle branch block (CRBBB). Methods: Sixty consecutive patients with normal QRS, CRBBB, or CLBBB were included. Stored raw data DICOM 2D apical-4 chambers view images cine clips were analyzed using EchoPac plugin version 203 (GE Vingmed Ultrasound AS, Horten, Norway). In EchoPac–Q-Analysis, 2D strain application was selected. Instead of apical view algorithms, the SAX-MV (short axis—mitral valve level) algorithm was selected for analysis. A closed loop endocardial contour was drawn to initiate the analysis. The “posterior” segment (representing the mitral valve) was excluded before finalizing the analysis. Longitudinal rotation direction, peak angle, and time-to-peak rotation were recorded. Results: All patients with CLBBB (n = 21) had clockwise longitudinal rotation with mean four chamber peak rotation angle of −3.9 ± 2.4°. This rotation is significantly larger than in patients with normal QRS (−1.4 ± 3°, p = 0.005) and CRBBB (0.1 ± 2.2°, p = 0.00001). Clockwise rotation was found to be correlated to QRS duration in patients with the non-RBBB pattern. The angle of rotation was not associated with a lower ejection fraction or the presence of regional wall abnormalities. Conclusions: Significant clockwise longitudinal rotation was found in CLBBB patients compared to normal QRS or CRBBB patients using speckle-tracking echocardiography.
- Published
- 2023
- Full Text
- View/download PDF
9. Verity Lambert's Thorn-EMI Films.
- Author
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Moody, Paul
- Subjects
OUTER space ,CONTENT analysis ,FILM archives ,HISTORY of archives ,ORDNANCE - Abstract
Verity Lambert's brief period as Director of Production at Thorn-EMI Screen Entertainment (TESE) was responsible for the in-house development of five films: Morons from Outer Space (1985), Restless Natives (1985), Dreamchild (1985), Link (1986) and Clockwise (1986), although she had left the company before the last three were released. There has been limited critical engagement with these productions and Lambert's tenure in general, with the existing literature on this material tending to emphasise the eclectic nature of what were to be TESE's last releases before the company's sale to Cannon (Hill 1999; Moody 2018; Park 1990; Walker 1985; Walker 2004; Wickham and Mettler 2005). Drawing on a series of detailed interviews with former TESE Production Executive, Graham Easton, along with previously unreleased archival documents from the Film Finances archive, this article develops a more detailed textual analysis and production history of these releases, in order more clearly to map TESE's complexities during this period. By engaging more coherently with the themes and aesthetics of TESE's output, the article argues that there is a consistency to Lambert's productions which can be seen at both a thematic and a stylistic level, centred on notions of constraint and obstacles to communication, and that this was nurtured by the environment created by Lambert and the Film Finances completion bond for each film. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
10. Differential exhumation of ultrahigh-pressure metamorphic terranes: A case study from South Altyn Tagh, western China
- Author
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Guowei Zhang, Yuting Cao, Yongsheng Gai, Xiaoying Liao, Liang Liu, Tuo Ma, Lei Kang, Wenqiang Yang, and Chao Wang
- Subjects
Subduction ,Metamorphic rock ,Geochronology ,Geochemistry ,Metamorphism ,Geology ,Clockwise ,Eclogite ,Zircon ,Terrane - Abstract
South Altyn Tagh contains ultrahigh-pressure (UHP) terranes that have been exhumed from ~300 km mantle depth. Previous zircon U–Pb geochronology has yielded an eclogite-facies age of ca. 500 Ma and a high-pressure (HP) granulite-facies retrograde age of ca. 450 Ma in the Jianggalesayi area in the western segment of South Altyn Tagh. However, in the eastern segment (Yinggelisayi and Danshuiquan localities), an age range of 500–480 Ma has been determined, and it remains uncertain as to whether this age range represents the timing of the peak metamorphic stage or the retrograde overprint. Our study of newly discovered retrograde eclogite in the Danshuiquan locality shows that it underwent three stages of metamorphism, under eclogite-facies, HP granulite-facies and amphibolite-facies P–T conditions of 2.5–4.0 GPa and 870–1050 °C, 2.0–1.4 GPa and 830–940 °C, and 0.7–1.3 GPa and 704–880 °C, respectively. The decompression-dominated P–T path evolved mainly after crossing the solidus, indicating marked retrograde modification under melt-bearing conditions. LA–ICP–MS and SIMS zircon U–Pb dating yielded ca. 500 Ma eclogite-facies and ca. 484 Ma granulite-facies retrograde ages and a later retrograde age of ca. 452 Ma. The clockwise P–T–t path indicates rapid exhumation from eclogite-facies to granulite-facies within around 16 Myr, which is faster than that of the UHP rocks in the western segment. Thus, the HP–UHP rocks in South Altyn Tagh suggest a differential exhumation process for the eastern and western segments. The distinct HP–UHT metamorphism and rapid exhumation of (U)HP rocks in the eastern segment likely resulted from local mantle heating. The continuing P–T evolution of the (U)HP rocks under UHT conditions during exhumation led to a pervasive granulite-facies overprint in the eastern segment of the South Altyn Tagh. The rapid exhumation recorded in the eastern segment provides valuable insights into the exhumation mechanism of ultra-deep subducted UHP terranes.
- Published
- 2022
11. Left Ventricular “Longitudinal Rotation” and Conduction Abnormalities—A New Outlook on Dyssynchrony
- Author
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Carasso, Ibrahim Marai, Rabea Haddad, Nizar Andria, Wadi Kinany, Yevgeni Hazanov, Bruce M. Kleinberg, Edo Birati, and Shemy
- Subjects
CLBBB ,clockwise ,longitudinal ,rotation - Abstract
Background: The complete left bundle branch block (CLBBB) results in ventricular dyssynchrony and a reduction in systolic and diastolic efficiency. We noticed a distinct clockwise rotation of the left ventricle (LV) in patients with CLBBB (“longitudinal rotation”). Aim: The aim of this study was to quantify the “longitudinal rotation” of the LV in patients with CLBBB in comparison to patients with normal conduction or complete right bundle branch block (CRBBB). Methods: Sixty consecutive patients with normal QRS, CRBBB, or CLBBB were included. Stored raw data DICOM 2D apical-4 chambers view images cine clips were analyzed using EchoPac plugin version 203 (GE Vingmed Ultrasound AS, Horten, Norway). In EchoPac–Q-Analysis, 2D strain application was selected. Instead of apical view algorithms, the SAX-MV (short axis—mitral valve level) algorithm was selected for analysis. A closed loop endocardial contour was drawn to initiate the analysis. The “posterior” segment (representing the mitral valve) was excluded before finalizing the analysis. Longitudinal rotation direction, peak angle, and time-to-peak rotation were recorded. Results: All patients with CLBBB (n = 21) had clockwise longitudinal rotation with mean four chamber peak rotation angle of −3.9 ± 2.4°. This rotation is significantly larger than in patients with normal QRS (−1.4 ± 3°, p = 0.005) and CRBBB (0.1 ± 2.2°, p = 0.00001). Clockwise rotation was found to be correlated to QRS duration in patients with the non-RBBB pattern. The angle of rotation was not associated with a lower ejection fraction or the presence of regional wall abnormalities. Conclusions: Significant clockwise longitudinal rotation was found in CLBBB patients compared to normal QRS or CRBBB patients using speckle-tracking echocardiography.
- Published
- 2023
- Full Text
- View/download PDF
12. Numerical simulation of land and sea-breeze (LSB) circulation along the Guinean Coast of West Africa
- Author
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Coulibaly, Amadou, Omotosho, Bayo J., Sylla, Mouhamadou B., Diallo, Yacouba, and Ballo, Abdoulaye
- Published
- 2021
- Full Text
- View/download PDF
13. Incidence of Uterine Torsion and Related Factors in Buffaloes of Amul Milk Shed Area.
- Author
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Pateliya, Chintan S., Patel, J. A., Dhami, A. J., Patel, S. B., and Makwana, H. L.
- Subjects
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CESAREAN section , *MILK , *SPERMATIC cord torsion , *UTERINE rupture - Abstract
A study was carried out to find out the retrospective incidence of uterine torsion in buffaloes among obstetrical cases in Amul milk shed area and factors influencing it. Data on 1,13,772 obstetrical cases attended from January 2017 to June 2018 by Amul Veterinarians were collected. Moreover, 50 buffaloes suffering from uterine torsion were taken up during July-December, 2018 to know the side, site, degree of uterine torsion, parity as well as sex and viability of the calf and the dam after detorsion/Caesarean section in the same area. In the retrospective study, a total of 2000 cases of uterine torsion were recorded among total 1,13,772 bovine obstetrical cases, which encompassed 1.76%. Of the 2000 cases, 92.20 (1844) percent torsions were found in buffaloes only. Among 57,111 obstetrical cases attended in buffaloes, the incidence of uterine torsion was 3.23%. Moreover, the region/center-wise incidence of torsion cases varied from 1.30-19.36%. The highest incidence of uterine torsion was found in Anand region (19.36 %) followed by Kathlal (11.23 %) and Mahemdabad (10.14 %) regions, while the lowest incidence was in Virpur (2.06%), Petlad (1.46%) and Piplata (1.30%). It was concluded that buffaloes mostly experience right side (100%), post-cervical (82%) uterine torsion of 270-360° (66%), at full term of gestation (70%) with lower survivability of the calves (30%), however, the survival rate of the dams post-treatment was 90%. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
14. Heat transfer and pressure drop characteristics of alternating clockwise and counter clockwise twisted tape inserts in the transitional flow regime.
- Author
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Abolarin, S.M., Everts, M., and Meyer, J.P.
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HEAT transfer , *PRESSURE drop (Fluid dynamics) , *HEAT flux , *PLATE , *TURBULENT flow , *TRANSITION flow - Abstract
Highlights • Heat transfer and pressure drop in the transitional flow regime. • Experiments with clockwise and counter clockwise twisted tape inserts. • Tape connection angle enhanced heat transfer. • Start and end of transition depended on connection angle and heat flux. • Earlier transition with increased connection angle and decreased heat flux. Abstract The purpose of this study was to experimentally investigate the heat transfer and pressure drop characteristics in a smooth circular tube with alternating clockwise and counter clockwise twisted tape (CCCTT) inserts. The CCCTT inserts were fabricated from copper plate strips with a length, width and thickness of 450 mm, 18 mm and 1 mm respectively. The strips were twisted to obtain a twist ratio of 5 and 12 strips were joined longitudinally so that a clockwise direction twisted tape insert was connected to a counter clockwise direction twisted tape. The assembling was at connection angles of 0°, 30° and 60°, to form CCCTT inserts with an overall length of 5.27 m. The CCCTT inserts were placed in a smooth circular copper tube with an inner diameter of 19 mm. Water was used as the test fluid and experiments were conducted at constant heat fluxes of 1.35, 2, 3 and 4 kW/m2 between Reynolds numbers of 300 and 11,404. This covered the laminar, transitional and turbulent flow regimes. Specific attention was given to the identification of the transitional flow regime with the CCCTT inserts and the influence of the connection angle and heat flux on the transitional flow regime. It was found that both the start and the end of the transitional flow regime were influenced by the connection angle and the heat flux. When different connection angles were compared it was found that an increase in connection angle enhanced the heat transfer in the transitional flow regime. An increase in heat flux significantly enhanced the heat transfer in the laminar flow regime and delayed transition. Heat transfer and pressure drop correlations were developed to predict the experimental data in the laminar, transitional and turbulent regimes as a function Reynolds number, modified Grashof number and connection angle. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
15. Subjective visual vertical in posterior canal benign paroxysmal positional vertigo patients before and after Canalith repositioning maneuvers.
- Author
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El-Minawi, Mohamed Sherif, Dabbous, Abeir Osman, Medhat, Mariam Magdy, and El-Dessokey Madkour, Lamiaa Ahmed
- Subjects
PATIENT positioning ,VERTIGO ,VESTIBULAR apparatus ,VESTIBULAR function tests ,VISUAL perception ,DESCRIPTIVE statistics ,BENIGN paroxysmal positional vertigo - Abstract
Background: The subjective visual vertical (SVV) is a measure of otolith-mediated verticality perception. The aim of this study was to test otolith function using the SVV in patients with posterior canal (PC) benign paroxysmal positional vertigo (BPPV) before and after Epley's Canalith repositioning maneuver (CRM). Methodology: This study included 20 PC BPPV patients and 20 healthy control subjects. SVV was tested using special equipment, at the time of BPPV diagnosis, then after CRM, and then 1 week after the resolution of vertigo and nystagmus. SVV was determined from clockwise (CW) and counter-clockwise (CCW) directions. The absolute average and the conventional numerical average was calculated. Results: Using the conventional method, there was no statistically significant difference between BPPV and their controls regarding either the CW or the CCW-SVV or the average slope. There was no statistically significant difference between CW and CCW-SVV in the patients. There was no statistically significant difference in the mean SVV values or the distribution of normal and abnormal results or the distribution of the SVV tilt between both-sided BPPV. Using the absolute average, SVV tilt was significantly higher in the patients than the controls. The preset angle affected the result. The mean SVV was significantly lower after resolution of BPPV than before treatment. Conclusion: Absolute SVV average was more accurate than numerical SVV average. There was a reduction of the SVV tilt after the CRM in BPPV patients. So, the SVV test can be used as a prognostic test for BPPV improvement after treatment. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
16. An Automatic Algorithm for Estimating Tropical Cyclone Centers in Synthetic Aperture Radar Imagery
- Author
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Lin Ren, Xiaohui Li, Bin Liu, Xiaofeng Li, Gang Zheng, Peng Chen, Lizhang Zhou, and Yan Wang
- Subjects
Synthetic aperture radar ,Position (vector) ,Track (disk drive) ,Perpendicular ,General Earth and Planetary Sciences ,Center (algebra and category theory) ,Stage (hydrology) ,Clockwise ,Electrical and Electronic Engineering ,Tropical cyclone ,Algorithm ,Geology - Abstract
Synthetic aperture radar (SAR) can monitor the sea surface imprints of tropical cyclones (TCs) with high spatial resolution, day and night. Automatically locating TC center positions in SAR images is a challenging task. This article developed a two-stage, fully automatic TC-center estimation algorithm. First, the sea surface wind directions (SSWDs) at SSWD points are retrieved by the improved local gradient (ILG) method. We incrementally deflected the SSWD outward at a 0.5° angle from -50° to 10° (the negative angles represent clockwise deflection). The heat maps are generated for each of the 121 angles, and the values at each heat map are the cumulative numbers of the lines perpendicular to the compensated SSWDs. The site corresponding to the maximum cumulative number in all 121 heat maps is the coarsely estimated center position. This center search is the culmination if it falls outside the SAR image. Otherwise, the second stage is triggered, and the sub-SAR image (150 km x 150 km) centered at the coarsely estimated center position is extracted. Then, the first-stage procedure is repeated with the sub-SAR image to precisely estimate the center position. Optionally, the precisely estimated center position can be further adjusted by considering that normalized radar cross section (NRCS) is normally minimal at the TC center. We applied the algorithm to 87 SAR images. Five of these images do not contain TC centers. The results are in good agreement with the visually located TC center positions and those in the best track (BT) datasets.
- Published
- 2022
17. Three-dimensional evaluation of distal and proximal segment skeletal relapse following isolated mandibular advancement surgery in 100 consecutive patients: A one-year follow-up study
- Author
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Constantinus Politis, Sohaib Shujaat, Reinhilde Jacobs, and E. Shaheen
- Subjects
Adult ,Male ,Cone beam computed tomography ,medicine.medical_specialty ,Adolescent ,One year follow up ,Cephalometry ,medicine.medical_treatment ,Osteotomy, Sagittal Split Ramus ,Sagittal split osteotomy ,Follow-up studies ,Mandible ,Mandibular advancement ,Genioplasty ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Recurrence ,medicine ,Humans ,Clockwise ,Reduction (orthopedic surgery) ,business.industry ,030206 dentistry ,Surgery ,Otorhinolaryngology ,Male patient ,030220 oncology & carcinogenesis ,Three-dimensional imaging ,Female ,Distal segment ,Oral Surgery ,business ,Mandibular Advancement ,Follow-Up Studies - Abstract
The aim of this study was to perform a three-dimensional evaluation of the skeletal relapse of the proximal and distal mandibular segments following isolated bilateral sagittal split osteotomy advancement surgery. One hundred consecutive patients (mean age 25.8±11.7 years), comprising 65 female patients (mean age 26.4±12.1 years) and 35 male patients (mean age 24.6±11.0 years) requiring mandibular advancement without genioplasty, were enrolled prospectively in the study. Cone beam computed tomography scans were acquired for each patient at three time-points: preoperatively, immediately (1-6 weeks) after surgery, and 1 year after surgery. A validated tool was utilized to assess the surgical movement and relapse. Based on percentage, the majority of the distal and proximal translational and rotational movements relapsed within the range of ≤2mm and ≤2°. The distal segment revealed a significant relapse in a posterior, inferior, and clockwise pitch direction. Both left and right proximal segments showed a significant translational relapse in the medial, posterior, and superior direction. Amongst the rotational parameters, proximal segments relapsed significantly in clockwise pitch, clockwise roll, and counterclockwise yaw direction. Overall, both distal and proximal bone segments showed a clinically acceptable translational and rotational stability. The proximal segments torqued towards their original position with a reduction of flaring. ispartof: INTERNATIONAL JOURNAL OF ORAL AND MAXILLOFACIAL SURGERY vol:51 issue:1 pages:113-121 ispartof: location:Denmark status: published
- Published
- 2022
18. Pre-maxillary complex morphology in bilateral cleft and hypothesis on laterality of deviated pre-maxilla
- Author
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Jyotsna Murthy and Devi Manisha
- Subjects
anticlockwise ,bilateral complete cleft of primary and secondary palate ,clockwise ,cross-sectional ,pre-maxilla ,pre-maxillary-vomerine complex ,pre-maxillary-vomerine suture ,retrospective ,Surgery ,RD1-811 - Abstract
Introduction: Pre-maxillary complex (pre-maxilla [PMX] + vomer) morphology in bilateral complete cleft of primary and secondary palate (BCLCP) is very complex and less reviewed in literature. Materials and Methods: In this retrospective cross-sectional study, 200 consecutive BCLCP patients were selected. Their pre-operative clinical photographs and dental casts were evaluated by a single investigator at two different points of time, to study the morphology of PMX and vomer with special emphasis on deviation of vomer and rotation of PMX. Results: It is found that in above 70% of patients, PMX and vomer both displaced or deviated towards left side in horizontal plane and PMX rotated anticlockwise at PMX vomerine suture (PVS). In 10% of cases, both PMX and vomer are displaced towards the right side, PMX rotated clockwise at PVS. In 11% of cases, vomer is displaced towards the left side, but PMX rotated clockwise at PVS. In 5% of cases, vomer is displaced towards the right side, but PMX rotated anticlockwise at PVS. Both PMX and vomer are in midline in 4% of cases. Conclusion: Specific morphological deviation of vomer and PMX has been studied. We put forward the probable hypothesis to explain the deviation and rotation of PMX.
- Published
- 2016
- Full Text
- View/download PDF
19. Characterization of the accommodation zones along restraining and releasing bends from analogue modelling simulating the seagap fault, off-shore Tanzania
- Author
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Godson Godfray, Michael Msabi, and Nasra Sadiki
- Subjects
Sandbox experiments ,Oils, fats, and waxes ,Inversion (geology) ,Energy Engineering and Power Technology ,Geometry ,02 engineering and technology ,Fault (geology) ,010502 geochemistry & geophysics ,01 natural sciences ,020401 chemical engineering ,Geochemistry and Petrology ,Orientation (geometry) ,TP670-699 ,Clockwise ,0204 chemical engineering ,Petroleum refining. Petroleum products ,0105 earth and related environmental sciences ,geography ,geography.geographical_feature_category ,Syn-kinematic sedimentation ,Restraining and releasing bends ,Geology ,Strike-slip tectonics ,Sinistral and dextral ,Analogue modelling ,Seagap faults ,Growth fault ,TP690-692.5 - Abstract
The study aims to understand geometry and evolution of accommodation zones along restraining and releasing bends in strike slip systems which is often complex and characterized by sharp change in polarity, resulting in a difficult characterization of traps location. A batch of sandbox modelling experiments was performed using a layered scaled sand material. The setup parameters of the wooden baseplates used in the first two experiments (SS1 and SS2) are basement offset of 6.5 cm/3 cm, 90°/90° stepovers in releasing and restraining bends of total 96 cm length and 25 cm width. The third experiment (SS3) was performed with basement offset of 6.5 cm/3 cm, 156°/126° stepovers in releasing and restraining bends of total 96 cm length and 25 cm width. The experiments were performed with special attention to the role of syn-kinematic sedimentation and the pre-existing structure of the basement. A sequence of pop-up and pull-apart structures was produced. Along the main structures, complex fault trend was compatible with a sinistral riedel distribution and a counterclockwise rotation of pre-existent elements. Change of fault's polarity at depth and dip direction flipping of high angle faults in accommodation zones were clearly observed. Even more, progressive propagation of the pop-up structures produces a spectacular inversion of adjacent extensional structures. Comparing results of the model with the Seagap fault zone, it is possible to put in evidence similar fault orientation and distribution. Internal structures developed were strongly influenced by syn-kinematic sedimentation as observed by characteristic helicoidal shape of growth faults. The analogue models clearly describe how boundary faults of the pull-apart basin along a paired bend, initially characterized by a normal kinematic can be subsequently inverted in the later stages, which can potentially have a strong impact on the petroleum system.
- Published
- 2021
20. Paleomagnetism of the Carboniferous–Permian Myall blocks, Tamworth Belt, southern New England Orogen: Permian counterclockwise rotations and Triassic clockwise rotation
- Author
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Chris T. Klootwijk
- Subjects
Paleomagnetism ,Paleontology ,New england ,Permian ,Carboniferous ,Earth and Planetary Sciences (miscellaneous) ,General Earth and Planetary Sciences ,Clockwise ,Geology - Published
- 2021
21. A Three-Dimensional Finite Element Analysis: Maxillary Dentition Distalization with the Aid of Microimplant in Lingual Orthodontics
- Author
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Dong-Liang Zhang, Wei-Hang Zhuang, and Xin He
- Subjects
Orthodontics ,Maxillary dentition ,business.industry ,medicine.medical_treatment ,movement pattern ,International Journal of General Medicine ,General Medicine ,Lingual orthodontics ,3-D finite element analysis ,Crown (dentistry) ,maxillary dentition ,stomatognathic diseases ,Movement pattern ,stomatognathic system ,anterior teeth ,lingual orthodontic ,medicine ,Maxillary central incisor ,Clockwise ,Implant ,height of power-arm ,business ,Anterior teeth ,Original Research - Abstract
Xin He,1 Wei-Hang Zhuang,2 Dong-Liang Zhang1 1Department of Orthodontics, School of Stomatology, Capital Medical University, Beijing, 100050, Peopleâs Republic of China; 2Department of Stomatology, Beijing Rytime Dental Hospital, Beijing, 100024, Peopleâs Republic of ChinaCorrespondence: Dong-Liang ZhangDepartment of Orthodontics, School of Stomatology, Capital Medical University, No. 11 Xila Hutong, Dongcheng District, Beijing, 100050, Peopleâs Republic of ChinaEmail zhangdongliang@hotmail.comAim: To analyze the movement of anterior teeth by changing the height of the power-arm and changing the force application points during whole maxillary dentition distalization with the aid of micro-implants in lingual orthodontics to set a biomechanical reference for effective clinical use of lingual orthodontic appliance.Methods: A three-dimensional finite element model of the maxillary teeth with lingual appliance and the associated support tissue was established. Maxillary dentition with the force of 200g was distalized using implant as anchorage, then the movement of anterior teeth was analyzed by changing the length of power-arm (1mm, 3mm, 6mm, 9mm) and by changing the force location from lingual side to buccal side.Results: During whole maxillary dentition distalization with aid of the implants in lingual orthodontics: when the height of power arm was 1mm, the anterior teeth rotated clockwise, with the increasing of the height of power-arm, the anterior teeth rotated counterclockwise gradually. When the height of power-arm was 9mm, all anterior teeth rotated counterclockwise. Central incisor and lateral incisor rotated counterclockwise and canine rotated clockwise when the buccal side force was applied.Conclusion: With the increase of the height of the power-arm, the movement pattern of the upper anterior teeth is different. The canine is more sensitive to the height of the power-arm than the central incisor and the lateral incisor. When the height of the power-arm reaches 9mm, the upper anterior teeth are displayed as crown tipping buccally movement. Compare with lingual side force, the buccal side force do better in preventing the loss of anterior tooth torque. If the upper anterior teeth are up-right or lingually tipped before treatment, it is preferable to use longer power-arm or buccal side traction force. If the anterior teeth are already tipped buccally, then short power-arm or lingual side force is advised.Keywords: lingual orthodontic, height of power-arm, movement pattern, 3-D finite element analysis, anterior teeth, maxillary dentition
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- 2021
22. Structural basis of bacterial flagellar motor rotation and switching
- Author
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Brittany L. Carroll, Yunjie Chang, and Jun Liu
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Microbiology (medical) ,0303 health sciences ,Bacteria ,Rotation ,030306 microbiology ,Stator ,Rotor (electric) ,Molecular Motor Proteins ,Bacterial motility ,Rotary machine ,Biology ,Microbiology ,Article ,law.invention ,03 medical and health sciences ,Infectious Diseases ,Bacterial Proteins ,Torque ,Flagella ,law ,Virology ,Biophysics ,Clockwise ,030304 developmental biology - Abstract
The bacterial flagellar motor, a remarkable rotary machine, can rapidly switch between counterclockwise (CCW) and clockwise (CW) rotational directions to control the migration behavior of the bacterial cell. The flagellar motor consists of a bi-directional spinning rotor surrounded by torque-generating stator units. Recent high-resolution in vitro and in situ structural studies have revealed stunning details of the individual components of the flagellar motor and their interactions in both the CCW and CW senses. In this review, we discuss these structures and their implications for understanding the molecular mechanisms underlying flagellar rotation and switching.
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- 2021
23. A stratigraphically significant new zosterophyllopsid from the Rhenish Lower Devonian (W Germany)
- Author
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Markus Poschmann, Rolf Gossmann, Peter Giesen, and Stephan Schultka
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Global and Planetary Change ,geography ,geography.geographical_feature_category ,Ecology ,biology ,Sporangium ,Paleontology ,Geology ,Massif ,biology.organism_classification ,Devonian ,Strobilus ,Zosterophyllum ,Clockwise ,Ecology, Evolution, Behavior and Systematics - Abstract
A new zosterophyllopsid species is formally described from the Lower Devonian of the central Rhenish Massif. This species, for which we propose the name Zosterophyllum confertum sp. nov., is common and hitherto restricted to Siegenian strata in terms of the regional (Rhenish) stratigraphic frame. It can easily be identified by the construction of its fertile parts (sporangia and strobilus shape), which are usually found in association with the axes. Among other characters, the new species is characterised in particular by the possession of very compact and terminally positioned mature strobili, which taper distally and comprise up to seven rows of helically and counter clockwise inserted, regularly spaced sporangia.
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- 2021
24. The counterclock ‐ clockwise approach for central hepatectomy: A useful strategy for a safe vascular control
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Eric Felli, Fabio Giannone, Emanuele Felli, Edoardo Maria Muttillo, and Lorenzo Cinelli
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medicine.medical_specialty ,Central Hepatectomy ,business.industry ,Liver Neoplasms ,Blood Loss, Surgical ,General Medicine ,Hepatic Veins ,Surgery ,Oncology ,Hepatic surgery ,medicine ,Hepatectomy ,Humans ,Clockwise ,business - Published
- 2021
25. The pattern of the inferocentral whorl region of the corneal subbasal nerve plexus is altered with age
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Mattias Andréasson, Per Svenningsson, Tor Paaske Utheim, Reza A. Badian, and Neil Lagali
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Disease status ,Plexus ,Microscopy, Confocal ,business.industry ,In vivo confocal microscopy ,General Practice ,Healthy subjects ,Nerve plexus ,Ophthalmic Nerve ,Anatomy ,Middle Aged ,Cornea ,Allmänmedicin ,body regions ,Ophthalmology ,Nerve Fibers ,medicine.anatomical_structure ,Diabetes Mellitus, Type 2 ,Subbasal nerve plexus ,Inferocentral whorl ,Diabetes mellitus ,Parkinsons disease ,Aging ,Humans ,Medicine ,Clockwise ,business ,Whorl (botany) - Abstract
Purpose: To describe the pattern of the nerves in the inferocentral whorl region of the human corneal subbasal nerve plexus (SBNP) in health and diseases known to affect the subbasal nerves. Methods: Laser-scanning in vivo confocal microscopy (IVCM) was used to image the SBNP bilaterally in 91 healthy subjects, 39 subjects with type 2 diabetes mellitus (T2DM), and 43 subjects with Parkinsons disease (PD). Whorl regions were classified according to nerve orientation relative to age and health/disease status. Results: Of 346 examined eyes, 300 (86.7%) had an identifiable whorl pattern. In healthy subjects, a clockwise nerve orientation of the whorl was most common (67.9%), followed by non-rotatory or seam morphology (21.4%), and counterclockwise (10.7%). The clockwise orientation was more prevalent in healthy subjects than in T2DM or PD (P < 0.001). Healthy individuals below 50 years of age had a predominantly clockwise orientation (93.8%) which was reduced to 51.9% in those over 50 years (P < 0.001). Age but not disease status explained whorl orientation in T2DM and PD groups. Moreover, whorl orientation is bilaterally clockwise in the young, but adopts other orientations and becomes asymmetric across eyes with age. Finally, we report reflective dot-like features confined to the whorl region of the subbasal plexus, sometimes appearing in close association with subbasal nerves and present in 84-93% of examined eyes regardless of disease status, eye or sex. Conclusion: Subbasal nerves in the inferocentral whorl region are predominantly clockwise in young, healthy corneas. With aging and conditions of T2DM and PD, counterclockwise and non-rotatory configurations increase in prevalence, and bilateral symmetry is lost. Mechanisms regulating these changes warrant further investigation. Funding Agencies|Hofgrens fond, NEURO Sweden
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- 2021
26. Crustal velocity and interseismic strain-rate on possible zones for large earthquakes in the Garhwal–Kumaun Himalaya
- Author
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Rajesh Sathiyaseelan, Param K. Gautam, John P. Pappachen, and Sanjit Kumar Pal
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Seismic gap ,Multidisciplinary ,Science ,Tectonics ,Active fault ,Strain rate ,Geodynamics ,Article ,Geophysics ,Large earthquakes ,Medicine ,Clockwise ,2008 California earthquake study ,Seismology ,Geology - Abstract
The possibility of a major earthquake like 2015 Gorkha–Nepal or even greater is anticipated in the Garhwal–Kumaun region in the Central Seismic Gap of the NW Himalaya. The interseismic strain-rate from GPS derived crustal velocities show multifaceted strain-rate pattern in the region and are classified into four different strain-rate zones. Besides compressional, we identified two NE–SW orienting low strain rate (~ 20 nstrain/a) zones; namely, the Ramganga-Baijro and the Nainital-Almora, where large earthquakes can occur. These zones have surface locking widths of ~ 72 and ~ 75 km respectively from the Frontal to the Outer Lesser Himalaya, where no significant surface rupture and associated large earthquakes were observed for the last 100 years. However, strain reducing extensional deformation zone that appears sandwiched between the low strain-rate zones pose uncertainties on the occurences of large earthquakes in the locked zone. Nevertheless, such zone acts as a conduit to transfer strain from the compressional zone (> 100 nstrain/a) to the deforming frontal active fault systems. We also observed a curvilinear surface strain-rate pattern in the Chamoli cluster and explained how asymmetric crustal accommodation processes at the northwest and the southeast edges of the Almora Klippe, cause clockwise rotational couple on the upper crust moving over the MHT.
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- 2021
27. The Z-Box illusion: dominance of motion perception among multiple 3D objects
- Author
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Michael D. Dodd and Joshua E. Zosky
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Computer science ,business.industry ,media_common.quotation_subject ,Illusion ,Experimental and Cognitive Psychology ,General Medicine ,Motion (physics) ,Orb (astrology) ,Arts and Humanities (miscellaneous) ,Perception ,Developmental and Educational Psychology ,Structure from motion ,Computer vision ,Clockwise ,Motion perception ,Artificial intelligence ,Cube ,business ,media_common - Abstract
In the present article, we examine a novel illusion of motion—the Z-Box illusion—in which the presence of a bounding object influences the perception of motion of an ambiguous stimulus that appears within. Specifically, the stimuli are a structure-from-motion (SFM) particle orb and a wireframe cube. The orb could be perceived as rotating clockwise or counterclockwise while the cube could only be perceived as moving in one direction. Both stimuli were presented on a two-dimensional (2D) display with inferred three-dimensional (3D) properties. In a single experiment, we examine motion perception of a particle orb, both in isolation and when it appears within a rotating cube. Participants indicated the orb’s direction of motion and whether the direction changed at any point during the trial. Accuracy was the critical measure while motion direction, the number of particles in the orb and presence of the wireframe cube were all manipulated. The results suggest that participants could perceive the orb’s true rotation in the absence of the cube so long as it was made up of at least ten particles. The presence of the cube dominated perception as participants consistently perceived congruent motion of the orb and cube, even when they moved in objectively different directions. These findings are considered as they relate to prior research on motion perception, computational modelling of motion perception, structure from motion and 3D object perception.
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- 2021
28. Comparison of bicortical, miniplate and hybrid fixation techniques in mandibular advancement and counterclockwise rotation: A finite element analysis study
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Serhat Can, Selcuk Basa, and Altan Varol
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Models, Anatomic ,Rotation ,Symphysis ,Finite Element Analysis ,Osteotomy, Sagittal Split Ramus ,Sagittal split osteotomy ,03 medical and health sciences ,Fixation (surgical) ,0302 clinical medicine ,Humans ,Medicine ,Displacement (orthopedic surgery) ,Clockwise ,030223 otorhinolaryngology ,Orthodontics ,business.industry ,Mandible ,030206 dentistry ,Finite element method ,Biomechanical Phenomena ,medicine.anatomical_structure ,Otorhinolaryngology ,Surgery ,Oral Surgery ,business ,Bone Plates ,Mandibular Advancement - Abstract
Objective This study aims to evaluate biomechanical stability and stress distribution of five different fixation types with finite element analysis using 10-mm advancement with or without counterclockwise rotation of the mandible. Materials and Methods After sagittal split osteotomy, 10-mm advancement was performed in the first group and 10-mm advancement and 10-degree counterclockwise rotation were performed in the second group. One miniplate (M-1), two-miniplate (M-2), one miniplate and a bicortical screw (H), l -shaped bicortical screw (B-1), and inverted l -shaped bicortical screw (B-2) systems were placed. Totally, 120 N force was applied to the models at a 45-degree angle from the lower edge of the symphysis. Results The highest values on fixation were seen with miniplate, while the mean values were obtained with bicortical screw system. The highest values on bone were achieved using bicortical screws. One miniplate (M-1) showed both the highest and mean displacement. The highest values in counterclockwise-rotated models increased in all parameters, compared to non-rotated models. Conclusion In cases in which passive alignment between segments and adequate bone contact are ensured, inverted l -shaped bicortical screw, two-miniplate, or hybrid systems are recommended.
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- 2021
29. The Moving Trajectory Fitting Based on Three-Dimensional Digital Model of Barchan Dunes in Taklimakan Desert
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Lia Aimin and Han Zhiwen
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Barchan ,GNSS applications ,Mode (statistics) ,Trajectory ,Regular polygon ,Range (statistics) ,Point (geometry) ,Clockwise ,Geodesy ,Geology - Abstract
In the hinterlands of the Taklimakan Desert, we monitored Barchan dune evolution with the Huace X90 GNSS in RTK working mode to obtain 3D coordinates of a dune with millimeter precision. Using these coordinates, a 3D digital model of the dune was built and superimposed with CASS 9.0 and ArcGIS 10.0. Auto CAD 2010 was used to draw an arc with the three elements of starting point, end point and included angle and to fit the corresponding characteristic point trajectory curve of the eight selected typical dunes. Results of the fitting showed that the dunes rotated counterclockwise with ranges of 33°∼38°and 25.5°∼30° in the monitoring intervals between stages one and two and stages three and four, respectively. The moving trajectories were curves pointing from NE to SW and convex to NW, with long lengths. Between stages two and three, the dunes rotated clockwise with a range of 31°∼37°, and the trajectories was curves pointing from NE to SW and convex to SE or SW, with varying direction and a short length. When the northward or southward angle between effective sand-driving wind and the axial direction was larger than 30°, the dune rotated clockwise or counterclockwise, respectively. This indicates that the moving trajectory should be a curve rather than a straight line, which would result in a better fit with the actual movement of the dune. Accurately fitting the moving trajectory of Barchan dunes can assist in learning how to fit the movement of other mobile dunes as well as how to correct raw dune evolution data, such as moving distance and speed. It can also lay a foundation for the improvement of a formula for moving speed, which is important because many fields of research concern the moving speed and direction of mobile dunes.
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- 2021
30. The Mechanism of Rock Mass Crack Propagation of Principal Stress Rotation in the Process of Tunnel Excavation
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Xinzhu Hua, Guanfeng Chang, Peng Li, and Jie Zhang
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Article Subject ,Computer simulation ,Physics ,QC1-999 ,Mechanical Engineering ,Magnitude (mathematics) ,Fracture mechanics ,Geotechnical Engineering and Engineering Geology ,Condensed Matter Physics ,Rotation ,Stress (mechanics) ,Brittleness ,Mechanics of Materials ,Geotechnical engineering ,Clockwise ,Rock mass classification ,Geology ,Civil and Structural Engineering - Abstract
Rock excavation has experienced complex stress paths. The development of the original crack under the path of principal stress magnitude and principal stress direction is a key scientific problem that needs to be solved in rock underground engineering. The principal stress magnitude dominates the initiation and propagation of the crack and increases rock damage under the action of principal stress rotation. In this study, the theoretical calculation and numerical analysis method have been combined with the crack propagation conditions to study the stress-driven mechanism of brittle rock crack propagation under principal stress rotation. The results show that the “relative initial angle” of crack angle is being updated in time during the principal stress rotation process; once the stress is rotated, it will become the next initial crack angle; the crack propagation direction is deviated under the applied shear load, and it is always in the direction of minimum shear load, leading to a certain degree of inhibition of crack propagation depth in the initial direction. According to the results of numerical simulation, the effect of principal stress rotation caused by mining excavation is obvious and has a certain range of influence depth, the stress of surrounding rock of roadway is the highest within the depth range of 1∼2 m, and the maximum principal stress is as high as 26.89 MPa. The rotation of principal stress direction on the roadway surrounding rock surface is the strongest, which makes the surrounding rock more fragmented, and the middle principal stress and the maximum principal stress rotate about 90° counterclockwise along the Ox axis. Studying the action mechanism of principal stress rotation on fractured rock masses can provide scientific basis for geotechnical engineering design and rock mass surrounding support.
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- 2021
31. Back-propagating rupture evolution within a curved slab during the 2019 Mw 8.0 Peru intraslab earthquake
- Author
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Kousuke Shimizu, Yuji Yagi, Ryo Okuwaki, and Yaping Hu
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Azimuth ,Geophysics ,Geochemistry and Petrology ,Epicenter ,Slab ,Magnetic dip ,Waveform ,Clockwise ,Slip (materials science) ,Waveform inversion ,Geology ,Seismology - Abstract
SUMMARY The 26 May 2019 MW 8.0 Peru intraslab earthquake ruptured the subducting Nazca Plate where the dip angle of the slab increases sharply and the strike angle rotates clockwise from the epicentre to north. To obtain a detailed seismic source model of the 2019 Peru earthquake, including not only the rupture evolution but also the spatiotemporal distribution of focal mechanisms, we performed comprehensive seismic waveform analyses using both a newly developed flexible finite-fault teleseismic waveform inversion method and a back-projection method. The source model revealed a complex rupture process involving a back-propagating rupture. The initial rupture propagated downdip from the hypocentre, then unilaterally northward along the strike of the slab. Following a large slip occurring ∼50–100 km north of the hypocentre, the rupture propagated bilaterally both further northward and back southward. The spatial distribution of focal mechanisms shows that the direction of T-axis azimuth gradually rotated clockwise from the epicentre northward, corresponding to the clockwise rotation of the strike of the subducting Nazca Plate, and the large-slip area corresponds to the high-curvature area of the slab iso-depth lines. Our results show that the complex rupture process, including the focal-mechanism transition, of the Peru earthquake was related to the slab geometry of the subducting Nazca Plate.
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- 2021
32. Rotation of the Philippine Sea plate inferred from paleomagnetism of oriented cores taken with an ROV-based coring apparatus
- Author
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Toshitsugu Yamazaki, Osamu Ishizuka, Naoki Uto, Shun Chiyonobu, Shinichi Takagawa, and Fumisato Tajima
- Subjects
Paleomagnetism ,geography ,QB275-343 ,QE1-996.5 ,geography.geographical_feature_category ,Seamount ,Geology ,Apparent polar wander ,Declination ,Coring ,Paleontology ,Tectonics ,Space and Planetary Science ,Ridge ,Kyushu-Palau ridge ,Philippine Sea plate ,Geography. Anthropology. Recreation ,Clockwise ,Geodesy - Abstract
Reconstructing the history of Philippine Sea (PHS) plate motion is important for better understanding of the tectonics of the surrounding plates. It is generally considered that the PHS plate migrated northward since Eocene, but its rotation has not been constrained well; some reconstructions incorporated a large clockwise rotation but others did not. This is mainly because the difficulty of collecting oriented rocks from the mostly submerged PHS plate hindered establishing an apparent polar wander path. In this study, we conducted a paleomagnetic study of oriented cores taken using an ROV-based coring apparatus from the Hyuga Seamount on the northern part of the Kyushu-Palau Ridge, a remnant arc in the stable interior of the PHS plate. Stepwise thermal and alternating-field demagnetizations were applied to specimens taken successively from two ~ 30 cm long limestone cores of middle to late Oligocene age, and characteristic remanent magnetization directions could be isolated. Declination and inclination of D = 51.5° and I = 39.8°, respectively, were obtained as the mean of the two cores. The easterly-deflected declination means ~ 50° clockwise rotation of the PHS plate since middle to late Oligocene. In addition, ~ 5° latitudinal change of the site is estimated from the mean inclination. The result implies that the Kyushu-Palau Ridge was located to the southwest of the present position in middle to late Oligocene, and that PHS plate rotation as well as the Shikoku and Parece Vela Basin spreading contributed to the eastward migration of the Izu-Ogasawara (Bonin) Arc to the current position.
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- 2021
33. Initiation of Clockwise Rotation and Eastward Transport of Southeastern Tibet Inferred from Deflected Fault Traces and GPS Observations
- Author
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Ling Zhang, Shiming Liang, Weijun Gan, Keliang Zhang, Genru Xiao, Keke Xu, Peter Molnar, Zhangjun Li, and Peizhen Zhang
- Subjects
geography ,geography.geographical_feature_category ,business.industry ,Global Positioning System ,Geology ,Clockwise ,Fault (geology) ,business ,Geodesy - Abstract
Eastward transport and clockwise rotation of crust around the southeastern margin of the Tibetan Plateau dominates active deformation east of the Eastern Himalayan Syntaxis. Current crustal movement inferred from GPS measurements indicates ongoing distortion of the traces of the active Red River fault and the Mesozoic Yalong-Yulong-Longmen Shan thrust belt. By extrapolating current rates back in time, we infer that this pattern of deformation developed since 10.1 ± 1.5 Ma. This date of initiation is approximately synchronous with a suite of tectonic phenomena, both near and far, within the wide Eurasia/Indian collision zone, including the initiation of slip on the Ganzi-Yushu-Xianshuihe fault and crustal thinning and E-W extension by normal faulting on N-S–trending rifts in the plateau interior. Accordingly, the eastward movement of eastern Tibet and the clockwise rotation of that material seem to be local manifestations of a larger geodynamic event at ca. 10–15 Ma that changed the kinematic style and reorganized deformation not only on the plateau-wide scale, but across the entire region affected by the India/Eurasia collision. Convective removal of some or all of Tibet's mantle lithosphere seems to offer the simplest mechanism for these approximately simultaneous changes.
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- 2021
34. Seismic Deformations in an Early Christian Monastery in the Area of Djanavara, Varna, Bulgaria. Part 2: Results of Investigations
- Author
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O. V. Dimitrov, A. A. Strelnikov, V. Tenekedjiev, E. A. Rogozhin, B. Ranguelov, A. M. Korzhenkov, A. Minchev, A. N. Ovsyuchenko, and A. S. Larkov
- Subjects
North wall ,Buttress ,business.industry ,Event (relativity) ,Early Christianity ,Vertical axis ,Clockwise ,Masonry ,business ,Joint (geology) ,Seismology ,Geology - Abstract
We conducted archaeoseismological studies at the Djanavara Monastery Complex in 2019. It consists of early medieval buildings of different ages, the main of which was the church. The church and the atrium were first badly damaged and then destroyed. There were attempts to repair them, as evidenced by the laying of a doorway in the north wall of the atrium. The age of this seismic event may coincide with the destruction of the “second” Episcopal Basilica of Varna, also built in the second half of the 5th century CE. This earthquake took place several decades later. Judging by the kinematic indicators in the building structures, the source of seismic movements was apparently located north-northeast of the Episcopal Basilica of Varna and, accordingly, of the Djanavara Monastery Complex. In this direction, the largest seismotectonic node is located at the intersection of sublatitudinal faults with the Shabla-Kaliakra seismogenic zone. Subsequent renovation of the Djanavara Church and construction of poor-quality buildings around it took place after this seismic event. However, even in these, later, walls, we see traces of younger seismic deformations, evidenced by numerous buttress walls attached to the walls that survived the second earthquake. Judging by the buttress walls attached to the original meridional walls from the east and west, the seismic movements of the second earthquake propagated along the east–west axis. The third seismic event put an end to the activity of the monastery complex. It can be seen that the repaired low-quality walls were again deformed: the later masonry that covered the doorway moved outward, and there was also a joint deformation of the meridional wall and its buttress. The westward movement of the latest masonry testifies to the source of seismic oscillations of this time, located west of the Djanavara Complex. However, the meridional walls show clockwise rotation of their parts, while a perpendicular wall was rotated counterclockwise. Such a systematic deformation presupposes the location of the seismic source not strictly to the west of the monastery complex, but to the southwest, which coincides with the direction to the source, which we determined for the deformations in the episcopal basilica of Varna. Some researchers believe that the Djanavara Monastery Complex was destroyed and finally abandoned in 614–615 CE during the Avar–Slavic invasion. However, there are materials indicating that residents left ancient Odessos even before the attack, most likely due to a strong (third in our case) earthquake, during which the entire city was engulfed in fires and many buildings were destroyed. We were unable to accurately estimate the local seismic intensity for each of the three described ancient earthquakes, however, such significant deformations as systematic inclination and shifting of walls, as well as rotations of their parts around the vertical axis, indicate that the intensity of seismic oscillations during the studied earthquakes reached IL ≤ 9 on the MSK-64 scale. The intensity of seismic oscillations may have been enhanced by unfavorable soil conditions at the site of the construction of the Djanavara Monastery Complex.
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- 2021
35. Seismic response of gas-hydrate zones: a case study from the Oman Sea
- Author
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Oz Yilmaz, Mojtaba S. Arabani, Ali Misaghi, and Nasser Keshavarz
- Subjects
Tectonics ,Geophysics ,Clathrate hydrate ,Seismic line ,Project area ,Sediment ,Submarine pipeline ,Thrust fault ,Clockwise ,Petrology ,Geology - Abstract
An offshore vintage 2D seismic dataset acquired in the Oman Sea recently has been reprocessed to achieve two objectives: mapping gas-hydrate zones and structural imaging beneath the bottom-simulating reflector (BSR). We present results of the analysis of the seismic data associated with three seismic lines in the project area. The sea-bottom water-saturated sediment column (WSZ) has an average thickness of 100 m and an interval velocity range of 1550–1700 m/s. The underlying gas-hydrate stability zone (GHSZ) has an average thickness of 180 m and an interval velocity range of 2000–2200 m/s. The BSR with its low-frequency, large-amplitude character is very prominent in the seismic images derived from prestack time migration (PSTM). The BSR defines the base of the GHSZ and thus is a crucial indicator of the presence of a gas-hydrate zone. Velocities close to the top of the GHSZ interval are slightly lower at some locations along the line traverses – indicative of a transitional boundary between the WSZ and GHSZ. The overthrust tectonics during the Mid-Miocene to Pliocene caused by the counterclockwise rotation of the Arabian Plate is evident in the seismic images. The resulting thrust faults may facilitate upward migration of fluids and gas, thus forming the free-gas zone beneath the BSRs.
- Published
- 2021
36. The fMRI study on specific Brain Activation when Turning Counterclockwise on a Running Track using the Traditional Motor Imagery Paradigm
- Author
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Jingu( Kim), Yujin Kim, and Sechang Kwon
- Subjects
Brain activation ,Motor imagery ,Computer science ,Track (disk drive) ,Clockwise ,Neuroscience - Published
- 2021
37. Multisensory contribution in visuospatial orientation: an interaction between neck and trunk proprioception
- Author
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Amir Kheradmand, Patricia Castro, Qadeer Arshad, Diego Kaski, Jason McCarthy, Rachael Cottier, and Joseph Buttell
- Subjects
medicine.medical_specialty ,media_common.quotation_subject ,Posture ,Sensory system ,Rotation ,Graviception ,Visual dependence ,Physical medicine and rehabilitation ,Orientation (geometry) ,Perception ,medicine ,Humans ,Clockwise ,Sensory cue ,media_common ,Proprioception ,General Neuroscience ,Subjective visual vertical ,Trunk ,Head Movements ,Space Perception ,Visual Perception ,Cervical ,Female ,Body ,Psychology ,Research Article - Abstract
A coherent perception of spatial orientation is key in maintaining postural control. To achieve this the brain must access sensory inputs encoding both the body and the head position and integrate them with incoming visual information. Here we isolated the contribution of proprioception to verticality perception and further investigated whether changing the body position without moving the head can modulate visual dependence—the extent to which an individual relies on visual cues for spatial orientation. Spatial orientation was measured in ten healthy individuals [6 female; 25–47 years (SD 7.8 years)] using a virtual reality based subjective visual vertical (SVV) task. Individuals aligned an arrow to their perceived gravitational vertical, initially against a static black background (10 trials), and then in other conditions with clockwise and counterclockwise background rotations (each 10 trials). In all conditions, subjects were seated first in the upright position, then with trunk tilted 20° to the right, followed by 20° to the left while the head was always aligned vertically. The SVV error was modulated by the trunk position, and it was greater when the trunk was tilted to the left compared to right or upright trunk positions (p p
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- 2021
38. Lagrangian-averaged vorticity deviation of spiraling blood flow in the heart during isovolumic contraction and ejection phases
- Author
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Kelvin Kian Loong Wong, Ke Yang, Dhanjoo N. Ghista, Oluwarotimi Williams Samuel, Hui Zhang, and Shiqian Wu
- Subjects
Physics ,0206 medical engineering ,Biomedical Engineering ,02 engineering and technology ,Blood flow ,Mechanics ,Vorticity ,020601 biomedical engineering ,030218 nuclear medicine & medical imaging ,Computer Science Applications ,Vortex ring ,Vortex ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,Flow (mathematics) ,Mitral valve ,medicine ,Clockwise ,Isovolumetric contraction - Abstract
The formation of vortex rings in the left ventricular (LV) blood flow is a mechanism for optimized blood transport from the mitral valve inlet to aortic valve outlet, and the vorticity is an important measure of a well-functioning LV. However, due to lack of quantitative methods, the process of defining the boundary of a vortex in the LV and identifying the dominant vortex components has not been studied previously. The Lagrangian-averaged vorticity deviation (LAVD) can enable us to compute the trajectory integral of the normed difference of the vorticity from its spatial mean. Therefore, in this work, we have employed LAVD to identify the Lagrangian vortices and Eulerian vortices for measuring the vortex volume and vorticity in the LV blood flow. We found that during the LV ejection period, the positive (counterclockwise) and negative (clockwise) vorticity of patients are consistently stronger than those of the healthy groups, and the counterclockwise vortex volume of healthy groups (0.84+0.26 ml) is greater than that of patients (0.55+0.28 ml) during the pre-ejection period. Then, during the middle ejection phase, the counterclockwise vortex ring volume of patients (1.89+0.36 ml) exceeds that of healthy groups (1.38+0.43 ml). Finally, during the end-ejection period, the counterclockwise vortex ring volume of healthy subjects (0.61+0.17 ml) is the same as that of patients (0.60+0.19 ml). The results presented in this paper can provide new insights into the blood flow patterns within the LV. It can accurately indicate the role of vortices and vorticity values in intra-LV flow, and portray how cardiomyopathy (and its distorted contractile mechanism) can affect intra-LV flow patterns and mitigate adequate LV outflow.
- Published
- 2021
39. Biomechanics of mini-implants : analysis of the adverse effects of four clinical situations and proposed resolutions
- Author
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Vanessa Valran, Baptiste Turrel, and Sarah Gebeile-Chauty
- Subjects
Dental Implants ,Molar ,Orthodontics ,Tooth Movement Techniques ,business.industry ,medicine.medical_treatment ,Finite Element Analysis ,Biomechanics ,General Medicine ,Traction (orthopedics) ,Rotation ,Biomechanical Phenomena ,stomatognathic diseases ,medicine.anatomical_structure ,stomatognathic system ,Incisor ,Mini implants ,Occlusal plane ,Maxilla ,Orthodontic Anchorage Procedures ,medicine ,Clockwise ,business - Abstract
The biomechanical adverse effects generated by our treatments must be considered among the failures of mini-implants, certainly excellent means of anchorage. The aim of this article was to illustrate and comment on mechanical adverse effects and to propose solutions. Four common clinical situations in vestibular technique are analyzed, decomposed three-dimensionally and solved. Maxillary incisor intrusion in direct traction (mini-implant between lateral incisors and canines in direct anchorage) can lead to a disto-labial rotation of the supporting teeth and an incisor flaring. Maxillary incisivo-canine retraction (mini-implant between 5 and 6 in direct anchorage) leads to a canine rotation, a clockwise rotation of the occlusal plane and a version of the adjacent teeth. The maxillary molar two-steps distalization (mini-implant between 5 and 6 with metal ligation to the canine) causes a rotation of the adjacent to the spring teeth, an incisor flaring and a molar disto-version. The protraction of a mandibular molar (mini-implant between 3 and 4 in direct anchorage) causes a disto-labial rotation, a lingual torque and a mesio-version of the molar as well as an incisor flaring and a clockwise rotation of the occlusal plan. The compensation bends on the adjacent teeth, the choice of the location and the type of mini-implant, the use of a power arms to get closer to the center of resistance are among the means of resolution. If mini-implants anchorage allows a significant quantitative effect, adverse effects should be considered individually with a three-dimensional biomechanical analysis.
- Published
- 2021
40. Petrology and P–T path of blueschists from central Qiangtang, Tibet: Implications for the East Paleo-Tethyan evolution
- Author
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Qing-guo Zhai, Wang Xu, Yong-Sheng Dong, and Fulai Liu
- Subjects
010504 meteorology & atmospheric sciences ,Subduction ,Geology ,010502 geochemistry & geophysics ,01 natural sciences ,Paleontology ,Gondwana ,Oceanic crust ,Laurasia ,Suture (geology) ,Clockwise ,Accretion (geology) ,0105 earth and related environmental sciences ,Petrogenesis - Abstract
The Paleo-Tethys Ocean records the initial geodynamic processes related to the dispersion of Gondwana and the subsequent accretion of Laurasia. However, whether the blueschist-bearing central Qiangtang metamorphic belt (CQMB) within the Qiangtang Block represents an in situ Paleo-Tethys suture remains controversial. Since the starting point of this debate is the subduction type (i.e., warm subduction vs. cold subduction) recorded by the associated central Qiangtang blueschists, here, we approach this debate by investigating their petrogenesis, which records the subduction and exhumation of an oceanic plate. We reconstruct the clockwise pressure–temperature (P–T) paths using phase equilibrium modeling for two types of blueschists from the Rongma and Gangma Co areas, and their peak P–T conditions reveal typical cold subduction with a uniform low geothermal gradient of 5–10 °C/km. Combining this information with published radiometric dating and bulk-rock geochemical data, we find that the central Qiangtang blueschists record almost all of the early Permian-Late Triassic subduction of the LSPTO and subsequent continental subduction, as well as the Late Triassic exhumation of oceanic and continental material. This study confirms that the central Qiangtang blueschist-bearing melange marks an in situ suture, which formed during the northward subduction and subsequent exhumation of the LSPTO.
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- 2021
41. High-resolution hydrodynamic modelling to study year-round circulations and inter-basin exchanges in Lake Winnipeg
- Author
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Jun Zhao, Luis F. León, Reza Valipour, and Yerubandi R. Rao
- Subjects
0106 biological sciences ,geography ,geography.geographical_feature_category ,Ecology ,Global wind patterns ,Buoy ,010604 marine biology & hydrobiology ,Forcing (mathematics) ,010501 environmental sciences ,Aquatic Science ,Structural basin ,01 natural sciences ,Ocean gyre ,Climatology ,Global Environmental Multiscale Model ,Bathymetry ,Clockwise ,Ecology, Evolution, Behavior and Systematics ,Geology ,0105 earth and related environmental sciences - Abstract
A new high-resolution (500 × 500 m), three-dimensional hydrodynamic model was applied to Lake Winnipeg to study summer and winter water circulation, temperature, and ice-cover during 2016–17. The model was run with a combination of buoy-based observations and the outputs from the Global Environmental Multiscale model forcing. Four primary riverine inflows and two outflows were considered in the model. The bathymetry from a previous study by the authors was revised using a 2018 survey covering the South Basin and the Narrows. Comparisons of this new model with the previous model setup (2 km resolution) show noticeable improvements in all simulated parameters. In the Narrows, where seiche-driven flows have predominant oscillation periods of ~27 h and ~17 h, the RMSE of simulated currents is 0.1 m s−1, half of that of the previous simulations. The new model was able to reasonably simulate the spatial development of ice-cover over the lake. The ice-free period circulation results show that there are two clockwise and counterclockwise gyres in the North Basin, and a weak seasonal clockwise gyre in the South Basin. Monthly circulation patterns differ from those during short wind events due to spatiotemporal variability of wind patterns. The materials from the Red and the Winnipeg Rivers need ~50 days to reach the Narrows before transported from the South Basin to the North Basin. The daily inter-basin exchange flow oscillations during the ice-free period can range up to ~3.5 × 104 m3 s−1, while under-ice daily exchanges are always northwards with values depending on inflowing riverine discharge up to ~0.5 × 104 m3 s−1.
- Published
- 2021
42. Intra-Individual Aging of the Facial Skeleton
- Author
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Nicolas Graillon, Thomas Radulesco, Justin Michel, Patrick Dessi, Charles Savoldelli, Eugénie Fourgeot, Pascal Adalian, Anthropologie bio-culturelle, Droit, Ethique et Santé (ADES), and Aix Marseille Université (AMU)-EFS ALPES MEDITERRANEE-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Male ,Aging ,[SHS.ANTHRO-BIO]Humanities and Social Sciences/Biological anthropology ,Population ,Facial Bones ,Bone remodeling ,03 medical and health sciences ,0302 clinical medicine ,Maxilla ,medicine ,Humans ,Clockwise ,030223 otorhinolaryngology ,education ,Retrospective Studies ,Orthodontics ,0303 health sciences ,education.field_of_study ,business.industry ,Infant ,General Medicine ,Intra individual ,Glabella ,Chin ,Cross-Sectional Studies ,medicine.anatomical_structure ,030301 anatomy & morphology ,Face ,Facial skeleton ,Female ,Surgery ,Crest ,business - Abstract
Background Midface skeletal changes through aging have been conceptualized as a clockwise rotation relative to the cranial base. This finding is mainly supported by cross-sectional population studies based on comparisons between groups of individuals in different age ranges. Few papers have evaluated the intra-individual evolution of the facial skeleton, and those that have included only a limited number of patients. Objectives The authors sought to analyze the intra-individual evolution of the facial skeleton. Methods We conducted a retrospective study including patients who underwent 2 separate facial computed tomography scans (T1 and T2) with a minimum gap of 7 years. Employing 3-dimensional reconstructions, we measured and compared 7 facial angles (glabellar, orbital, piriform, maxillary, subdental, chin, gonial) and 6 facial distances (lacrimal crest, orbital floor, piriform, zygoma, labiomental, gnathion) on both computed tomography scans. Results A total of 56 patients (29 males and 27 females) were included. Mean ages at T1 and T2 were 50 and 59 y, respectively. We found a significant decrease between T1 and T2 in facial angles at the midface (glabella, orbital, piriform, and maxillary angles, all P < 0.0001). We found a significant increase in all facial distances between T1 and T2 for the overall population and for men (all P < 0.05). For women, all distances increased, but only piriform and zygoma distances showed significant changes (P < 0.001 and P < 0.04, respectively). Bone remodeling appeared earlier in women. Conclusions Our study confirms the clockwise rotation of the midface during aging. This finding could lead to a better understanding of aesthetic medicine practices.
- Published
- 2021
43. The migration of the crustal deformation peak area in the eastern Himalayan Syntaxis inferred from present-day crustal deformation and morpho-tectonic markers
- Author
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Chenglong Dai, Xiaoping Yang, Shiming Liang, and Ling Zhang
- Subjects
010504 meteorology & atmospheric sciences ,Geophysics. Cosmic physics ,Present day ,Deformation (meteorology) ,010502 geochemistry & geophysics ,01 natural sciences ,Clockwise ,Computers in Earth Sciences ,0105 earth and related environmental sciences ,Earth-Surface Processes ,GPS velocity ,QB275-343 ,Syntaxis ,biology ,QC801-809 ,Morpho ,Strain rate ,biology.organism_classification ,Tectonics ,Geophysics ,Eastern himalayan syntaxis ,Landform ,Erosion ,Crustal deformation peak area ,Geology ,Seismology ,Geodesy - Abstract
The present-day Global Positioning System (GPS) velocity field shows that the Indian Plate is not a complete rigid block, as its northeastern corner has been torn off and clockwise rotating relative to the main part. With the updated GPS velocity data, the Euler vector of the northeastern corner of the Indian Plate relative to the stable main plate is deduced as (89.566 ± 0.06° E, 26.131 ± 0.05° N, 1.34 ± 0.11°/Myr). The peak area of the present-day crustal deformation is located in the Chayu deformation belt with the compressional dilation strain rate over 160 nanostrain/yr. However, the Namche-Barwa Syntaxis with the massive crustal thickening and intense surface erosion is generally considered to be the previous locus of the strongest compressional stress in the Eastern Himalayan Syntaxis over long geological timescales. Thus, there is a discrepancy between the previous and present-day crustal deformation peak areas. We argue the migration of the crustal deformation peak area with a total distance of about 120 km and ascribe it to the variation of stress conditions caused by northeast India's clockwise rotation.
- Published
- 2021
44. Effect of a current trapped by a continental slope on the pathway of a coastal current crossing Toyama Trough, Japan
- Author
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Yosuke Igeta, Taku Wagawa, Alexander E. Yankovsky, Ken-ichi Fukudome, Mizuki Kuga, Naoki Hirose, Atsushi Kaneda, Satoshi Ikeda, and Toshihiro Tsuji
- Subjects
geography ,Downstream Region ,geography.geographical_feature_category ,010504 meteorology & atmospheric sciences ,010505 oceanography ,Warm current ,Continental shelf ,Trough (geology) ,Oceanography ,Mooring ,01 natural sciences ,Current (stream) ,Submarine pipeline ,Clockwise ,Geomorphology ,Geology ,0105 earth and related environmental sciences - Abstract
To clarify the Tsushima Warm Current (TWC) system around a downstream region of Noto Peninsula (NP) where Toyama Trough (TT) causes a discontinuity of the along shelf-current, numerical experiments were performed using two-layered ocean model with simplified bottom topography. When a current trapped by the continental slope representing an offshore branch of TWC (OB) encounters the NP and TT, the OB was trapped by the coast facing the TT. A clockwise lee-eddy developed between a current axis and a coastline over the TT, which results in a current path transition offshore (CPT). The OB finally adjusted to a current path which crosses TT by shifting from the discontinuity point of the continental slope. If a coastal current representing a coastal branch of the TWC (CB) developed under this situation, the CB also formed lee-eddy within the identical region of the OB’s eddy, resulting in CPT. Period for the CPT of the CB was shorter with increase of the OB volume transport. These results indicate that the OB acted to accelerate CPT of the CB within the TT. To support these results, observational data comprising mooring current, tidal, and CTD measurements obtained in and around the TT, along with the output from high-resolution data-assimilated ocean model DR_C were analyzed. Although the lee-eddy of the CBs was generated in every summer, the CPT events did not fully develop when the OB was absent over the continental slope because of the slow growth rate of the lee-eddy.
- Published
- 2021
45. Seismic anisotropy accrued by seven unusually deep local earthquakes (between 50 and 60 km) in the Albertine Rift: implications of asthenospheric melt upwelling
- Author
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Andreas Schumann, E. Twesigomwe, and Arthur Batte
- Subjects
Seismic anisotropy ,Rift ,010504 meteorology & atmospheric sciences ,010502 geochemistry & geophysics ,01 natural sciences ,Geophysics ,Geochemistry and Petrology ,Lithosphere ,Clockwise ,Anisotropy ,Structural geology ,Geology ,Rift valley ,Seismology ,0105 earth and related environmental sciences ,Melt inclusions - Abstract
We investigated the primary mechanisms triggering the S-wave splitting (SWS) of seven unusually deep local earthquakes (between 50 and 60 km) which originated in the lithosphere beneath the Rwenzori region. We attempted to develop an understanding of the relationship between anisotropic structures in the lithosphere and tectonic deformation processes. A total of 12 out of 44 waveforms showed evidence of SWS on their polarization diagrams. The fast-wave direction (φ) and delay-time (δt) were estimated using the covariance matrix and the cross-correlation coefficient methods, respectively. We observed a clockwise rotation of φ-directions (NW - SE and ~ENE - WSW) at stations located in the rift valley. We related this pattern of φ-directions to anisotropic fabric, probably lattice-preferred orientation of preexisting olivine, whose a-axes are aligned with ESE absolute plate motion (APM) vector. At stations located outside the rift valley, however, we observed WNW - ESE and NNW - SSE patterns of φ-directions. We associated these patterns to the shape-preferred orientation of structures frozen in the lithosphere that are aligned with the present-day APM direction. We observed δt values ranging between 0.04 ± 0.01s and 0.43 ± 0.02 s, which decrease with distance away from the rift axis. This further supported our concept that the anisotropy observed at stations located on the moving plate is related to aligned melt inclusions frozen in the surrounding lithosphere. We further observed that the δt values increase linearly with ray-path length, which could indicate a fairly uniform anisotropy between 50-km and 60-km depth. Our study reported no evidence of multi-layer anisotropy beneath the Rwenzori region.
- Published
- 2021
46. BIOMECHANICAL JUSTIFICATION FOR EXTERNAL FIXATION OF THE PELVIS USING RODS WITH DIFFERENT THREAD HANDS
- Author
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Mykhailo Karpinsky, Sergiy Kovalyov, Valentyn Zhuravlyov, Andrii Istomin, and Dmytro Istomin
- Subjects
Orthodontics ,030222 orthopedics ,Osteosynthesis ,Computer science ,medicine.medical_treatment ,Thread (computing) ,Rod ,03 medical and health sciences ,External fixation ,0302 clinical medicine ,medicine.anatomical_structure ,medicine ,Clockwise ,Early rehabilitation ,030217 neurology & neurosurgery ,Pelvis ,Interlocking - Abstract
Background. External fixation devices (EFD) have found wide application in pelvic fractures treating, but it is not always that strength characteristics of these devices make it possible to realize early rehabilitation. Objective. the biomechanical justification for external pelvic osteosynthesis with use of rods having different thread hands on the basis of analysis of the stress-strain state (SSS) of the “EFD – pelvis” system and an experimental study of the strength of threaded connections of different rods and the pelvic bone under the effect of alternate cyclic loads. Materials and Methods. Was analyzed the SSS of the “EFD – pelvis” system verified in an experimental study of the strength of threaded connections of different rods and the pelvic bone under the effect of alternate cyclic loads. Results. Standing on a single basis in the AVF rods with the same thread, there are torques directed in different directions: on the right - clockwise (screwing in), on the left - counterclockwise (screwing out).A change in the thread direction does not lead to change in the moment values, but directions of the action of the moments of force for the left rod will correspond to the direction of its screwing both in the left- and right-sided one-support position. Conclusions. Bar-connected rods with a differently directed thread create a reciprocally interlocking structure, which counteracts self-unscrewing. Such a structure significantly increases the strength of connection of an EFD with the pelvic bone and creates conditions for an effective use of the early rehabilitation of patients with pelvic fractures.
- Published
- 2021
47. Testing normal fault growth models by seismic stratigraphic architecture: The case of the Pliocene‐Quaternary Fucino Basin (Central Apennines, Italy)
- Author
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Stefano Patruno and Vittorio Scisciani
- Subjects
geography ,Tectonics ,geography.geographical_feature_category ,Earthquake hazard ,Inversion (geology) ,Geology ,Clockwise ,Fault (geology) ,Structural basin ,Normal fault ,Quaternary ,Seismology - Abstract
[Abstract Normal faults grow either by radial propagation and segment linkage or by accruing displacement without a proportional increase in fault length. To test these competing models of fault growth, a novel 2D seismic stratigraphic interpretation of the recent Fucino Basin of the central Apennines (Italy) has been performed. The Fucino is a major Pliocene‐Quaternary non‐marine ‘extensional collapse basins’, developed immediately after the Apenninic compressional strain had locally abated, and bounded by seismogenic faults that generate strong (Mw = 6–7) and destructive earthquakes. The Fucino is an overall dual polarity half‐graben, built around two border fault systems: the northern one lies along the east‐northeast striking Avezzano‐Bussi regional fault‐zone; the other, south‐eastern trending, bounds the basin to the east. Two separate fault‐driven depocentres of fluvio‐lacustrine sequences (maximum thicknesses of ~1,750 m) are present. One is associated to the northern border faults, with mainly Late Pliocene activity; the second is to the hanging‐wall of the eastern border‐faults and reveals a stepwise Pleistocene‐Recent activity. Tectonic depocentres have migrated clockwise through time, and new‐born fault systems have developed at the south‐eastern basin periphery (Gioia dei Marsi area). This, together with the progressive accumulation of throw in time without significant fault lengthening, suggests that the model of fault growth by segment linkage is not the best explanation for this basin. Instead, the stepwise onset and growth of the Fucino extensional collapse faulting, and its ongoing earthquake hazard, may have been promoted by polyphase inversion tectonics of inherited deep‐seated zones of weaknesses (e.g. Avezzano‐Bussi Line)., The Fucino is an overall dual polarity half‐graben, built around two border fault systems: the northern one lies along the east‐northeast striking Avezzano‐Bussi regional fault‐zone; the other, south‐eastern trending, bounds the basin to the east. Two separate fault‐driven depocentres of fluvio‐lacustrine sequences (maximum thicknesses of ~1,750 m) are present. The northern border fault showed mainly a Late Pliocene activity; the eastern border‐faults reveal a stepwise Pleistocene‐Recent activity. Tectonic depocentres have migrated clockwise through time, and new‐born fault systems have developed at the south‐eastern basin periphery (Gioia dei Marsi area). This, together with the progressive accumulation of throw in time without significant fault lengthening, suggests that the model of fault growth by segment linkage is not the best explanation for this basin. ]
- Published
- 2021
48. Performance evaluation of a vertical rotating wick solar still
- Author
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M.M. Younes, Fadl A. Essa, Z.M. Omara, and A.S. Abdullah
- Subjects
021110 strategic, defence & security studies ,Thermal efficiency ,Environmental Engineering ,Materials science ,General Chemical Engineering ,Condensation ,0211 other engineering and technologies ,Rotational speed ,02 engineering and technology ,Mechanics ,010501 environmental sciences ,Solar still ,01 natural sciences ,Desalination ,Solar tracker ,Cotton cloth ,Environmental Chemistry ,Clockwise ,Safety, Risk, Reliability and Quality ,0105 earth and related environmental sciences - Abstract
In this work, a new solar still desalination system named vertical rotating wick solar still (VRWSS) was investigated experimentally. The experiments were performed under different operating conditions. The performance of VRWSS was investigated under different wick belt materials (jute and cotton cloth), belt rotational speeds (0.02, 0.05, 0.1, 0.2, and 0.3 rpm), and rotating directions (clockwise and counterclockwise) with and without solar tracking. The VRWSS features are its small size (small horizontal area), fast water evaporation and condensation due to the low thermal capacity and large condensation area. The results revealed that the jute wick obtained higher productivity than the cotton wick at all belt rotational speeds except that at 0.02 rpm. Additionally, the water production for VRWSS-counterclockwise movement increased from 4350 mL/m2.day at 0.02 rpm to 5800 mL/m2.day at 0.05 rpm, then, the productivity started to decrease with increasing the speed. Furthermore, VRWSS productivity with counterclockwise movement was always larger than that with clockwise direction at all rotational speed except at 0.02 rpm. Besides, the solar tracking for VRWSS (jute wick-counterclockwise-0.1 rpm) increased the freshwater productivity by about 37% with a thermal efficiency of 51%. The cost of produced freshwater from VRWSS was 0.02 $/L.
- Published
- 2021
49. Track distance runners exhibit bilateral differences in the plantar fascia stiffness
- Author
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Yasuo Kawakami, Munekazu Naito, Natsuki Sado, Ryo Yamashita, Tomohiro Mizokuchi, and Hiroto Shiotani
- Subjects
Adult ,Male ,Science ,Article ,Running ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Distance running ,medicine ,Humans ,Clockwise ,Muscle, Skeletal ,Ultrasonography ,Musculoskeletal system ,Multidisciplinary ,business.industry ,Track (disk drive) ,Stiffness ,030229 sport sciences ,Anatomy ,Biomechanical Phenomena ,Cross-Sectional Studies ,medicine.anatomical_structure ,Fasciitis, Plantar ,Athletes ,Foot arch ,Medicine ,Plantar fascia ,Tissue stiffness ,medicine.symptom ,business ,human activities ,030217 neurology & neurosurgery ,Foot (unit) - Abstract
Human steady-state locomotion modes are symmetrical, leading to symmetric mechanical function of human feet in general; however, track distance running in a counterclockwise direction exposes the runner’s feet to asymmetrical stress. This may induce asymmetrical adaptation in the runners’ foot arch functions, but this has not been experimentally tested. Here, we show that the plantar fascia (PF), a primary structure of the foot arch elasticity, is stiffer for the left than the right foot as a characteristic of runners, via a cross-sectional study on 10 track distance runners and 10 untrained individuals. Shear wave velocity (index of tissue stiffness: SWV) and thickness of PF and foot dimensions were compared between sides and groups. Runners showed higher PF SWV in their left (9.4 ± 1.0 m/s) than right (8.9 ± 0.9 m/s) feet, whereas untrained individuals showed no bilateral differences (8.5 ± 1.5 m/s and 8.6 ± 1.7 m/s, respectively). Additionally, runners showed higher left to right (L/R) ratio of PF SWV than untrained men (105.1% and 97.7%, respectively). PF thickness and foot dimensions were not significantly different between sides or groups. These results demonstrate stiffer PF in the left feet of runners, which may reflect adaptation to their running-specific training that involves asymmetrical mechanical loading.
- Published
- 2021
50. Correlations between left ventricular rotational mechanics and parasympathetic autonomic function—results from the three-dimensional speckle-tracking echocardiographic MAGYAR-Healthy Study
- Author
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Anita Kalapos, Csaba Lengyel, Péter Domsik, Attila Nemes, and Andrea Orosz
- Subjects
Autonomic function ,business.industry ,Short Communication ,Diaphragmatic breathing ,Speckle tracking echocardiography ,Mechanics ,030204 cardiovascular system & hematology ,03 medical and health sciences ,Speckle pattern ,Basal (phylogenetics) ,0302 clinical medicine ,Medicine ,030211 gastroenterology & hepatology ,Radiology, Nuclear Medicine and imaging ,Clockwise ,Systole ,Twist ,business - Abstract
Left ventricular (LV) twist is calculated from the net difference of counterclockwise apical and clockwise basal rotation during systole. The current study was designed to evaluate correlations between autonomic function and LV rotational mechanics in healthy subjects. The present study comprised 18 healthy subjects (mean age: 36±12 years, 12 men). Three-dimensional speckle tracking echocardiography (3DSTE) could be used for non-invasive evaluation of LV rotation and twist. Autonomic function was assessed by means of 5 standard cardiovascular reflex tests. During 3DSTE, basal LV rotation proved to be -3.24±2.02 degree, while apical LV rotation was 9.08±3.04 degree, therefore LV twist was 11.70±6.80 degree. Valsalva test showed significant correlations with LV basal (r=0.529, P=0.019) and apical rotations (r=-0.534, P=0.022), and LV twist (r=-0.467, P=0.044). Heart rate response to deep breathing significantly correlated with LV twist, as well (r=-0.452, P=0.052). The other tests had no any relationship with rotational characteristics. Correlations exist between parasympathetic autonomic function and 3DSTE-derived LV rotation and twist in healthy subjects.
- Published
- 2021
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