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Sample records for axial sagittal coronal

  1. Normal anatomy of the female pelvis in axial, coronal, and sagittal planes demonstrated with reformatted CT

    International Nuclear Information System (INIS)

    Constant, O.C.; Cooke, J.C.; Parsons, C.A.

    1987-01-01

    Axial CT is used in assessing gynecologic malignancies. Accurate delineation of local tumor extent in carcinoma of the cervix is important in initial staging and in planning subsequent management. A modified scanning technique produces reformatted coronal and sagittal images, which demonstrate additional valuable information about the cardinal ligaments, parametria, ureters, boundaries between the cervix, bladder, and rectum, and extension to vagina and uterus. This information is illustrated by representative axial, coronal, and sagittal scans. Familiarity with normal appearances is essential to allow correct interpretation of pathology

  2. The MRI findings of meniscal root tear of the medial meniscus: emphasis on coronal, sagittal and axial images.

    Science.gov (United States)

    Choi, Sang-Hee; Bae, Sooho; Ji, Suk Kyeong; Chang, Moon Jong

    2012-10-01

    The purpose of this study was to evaluate the accuracy of the characteristic magnetic resonance imaging (MRI) findings of medial meniscal root tear in the coronal, sagittal and axial planes. Thirty arthroscopically diagnosed patients who had undergone preoperative knee MRI were included in this study. They were compared to 30 age-matched patients with medial meniscus tears without root tears. The findings used for imaging analysis were as follows: the radial tear on the meniscal root of the medial meniscus in the axial plane, the presence of the truncation sign in the coronal plane and the ghost meniscus sign in the sagittal plane. Meniscal extrusion in the coronal plane was also evaluated. All the MRI findings of both groups were statistically analyzed. All the findings were more frequently found in the root tear group than those in the control group (P meniscal root tear were characteristic as compared with the control group. Radial tear in the axial plane also showed similar diagnostic accuracy as that seen in the other planes. The characteristic findings provide high diagnostic accuracy, and axial plane is helpful to detect medial meniscal root tear. Diagnostic study, Level III.

  3. Axial and coronal orientation of subaxial cervical zygapophysial joints and their effect on axial rotation and lateral bending.

    Science.gov (United States)

    Hsu, Wen-Hsing; Benzel, Edward C; Chen, Tzu-Yung; Chen, Yao-Liang

    2008-10-15

    Computerized tomography and image processing methodologies were used to analyze the axial and coronal orientation of cervical zygapophysial joints in asymptomatic adults. Surface motions of axial rotation and lateral bending were simulated. The study was designed to obtain the normal distribution and variation of facet orientation (FO) in axial and coronal planes to investigate factors affecting FO and to study the effects of FO on axial rotation and lateral bending. The FO of the subaxial cervical spine is usually evaluated in the sagittal plane. Cervical spine axial and coronal FO is usually considered to be horizontal. The literature reveals no statistical data for axial or coronal FO. Serial thin-sliced computed tomography scans of the cervical spine in asymptomatic adults were input into Image J, National Institutes of Health, image processing software. Bilateral zygapophysial joint angles from C2-C3 to C6-C7 were measured in the axial and coronal planes and collected from 100 subjects. The effect of gender, age, and correlation was analyzed. The surface motions of axial rotation and lateral bending were simulated in Abaqus CAE 6.5. Mathematical facet contact and range of motion were computed. The FO was widely distributed at each level. Gender had no significant association with FO. Age affected FO at most levels. Axial and coronal FO were significantly correlated. The zygapophysial joint of internally rotated/inverted FO contacted more perpendicularly to each other, and mathematical range of motion was smaller. The axial or coronal FO of the subaxial cervical spine was found with more variability. Age was significantly related to FO. Geometrically, internally rotated/inverted FO of axial rotation/lateral bending was morerestricted. The extent of axial rotation and lateral bending was correlated with each other.

  4. Evaluation of uterine peristalsis using cine MRI on the coronal plane in comparison with the sagittal plane.

    Science.gov (United States)

    Shitano, Fuki; Kido, Aki; Kataoka, Masako; Fujimoto, Koji; Kiguchi, Kayo; Fushimi, Yasutaka; Togashi, Kaori

    2016-01-01

    Uterine peristalsis is supposed to be closely related to the early stages of reproduction. Sperms are preferentially transported from the uterine cervix to the side of the tube with the dominant follicle. However, with respect to magnetic resonance imaging (MRI), uterine peristalsis has only been evaluated at the sagittal plane of cine MRI. To evaluate and compare uterine peristalsis both on sagittal and coronal planes using cine MRI. Internal ethics committee approval was obtained, and subjects provided informed written consent. Thirty-one women underwent MRI scans in the periovulatory phase of the menstrual cycle. Cine MR images obtained by fast advanced spin echo sequence at 3-T field strength magnet (Toshiba Medical Systems) were visually evaluated by two independent radiologists. The frequency and the direction of peristalsis, and the presence of outer myometrium conduction of signal intensities (OMC), were evaluated. The laterality of the dominant follicle was determined on axial images and compared with the peristaltic direction in fundus. The subjects in which peristaltic directions were more clearly recognized were significantly frequent in coronal planes than in sagittal planes (P < 0.05). There was no significant difference in the peristaltic frequency between the sagittal and the coronal plane. However, the OMC was more recognized in the coronal plane than in the sagittal plane (P < 0.05). Peristaltic waves conducted toward the possible ovulation side were observed in only three of the 10 subjects. OMC of uterine peristalsis was better demonstrated in the coronal plane compared to the sagittal plane. © The Foundation Acta Radiologica 2015.

  5. An algorithm based on OmniView technology to reconstruct sagittal and coronal planes of the fetal brain from volume datasets acquired by three-dimensional ultrasound.

    Science.gov (United States)

    Rizzo, G; Capponi, A; Pietrolucci, M E; Capece, A; Aiello, E; Mammarella, S; Arduini, D

    2011-08-01

    To describe a novel algorithm, based on the new display technology 'OmniView', developed to visualize diagnostic sagittal and coronal planes of the fetal brain from volumes obtained by three-dimensional (3D) ultrasonography. We developed an algorithm to image standard neurosonographic planes by drawing dissecting lines through the axial transventricular view of 3D volume datasets acquired transabdominally. The algorithm was tested on 106 normal fetuses at 18-24 weeks of gestation and the visualization rates of brain diagnostic planes were evaluated by two independent reviewers. The algorithm was also applied to nine cases with proven brain defects. The two reviewers, using the algorithm on normal fetuses, found satisfactory images with visualization rates ranging between 71.7% and 96.2% for sagittal planes and between 76.4% and 90.6% for coronal planes. The agreement rate between the two reviewers, as expressed by Cohen's kappa coefficient, was > 0.93 for sagittal planes and > 0.89 for coronal planes. All nine abnormal volumes were identified by a single observer from among a series including normal brains, and eight of these nine cases were diagnosed correctly. This novel algorithm can be used to visualize standard sagittal and coronal planes in the fetal brain. This approach may simplify the examination of the fetal brain and reduce dependency of success on operator skill. Copyright © 2011 ISUOG. Published by John Wiley & Sons, Ltd.

  6. Brief communication: age and fractal dimensions of human sagittal and coronal sutures

    DEFF Research Database (Denmark)

    Lynnerup, Niels; Jacobsen, Jens Christian Brings

    2003-01-01

    The fractal dimensions of human sagittal and coronal sutures were calculated on 31 complete skulls from the Terry Collection. The aim was to investigate whether the fractal dimension, relying on the whole sutural length, might yield a better description of age-related changes in sutural morphology......, as opposed to other methods of quantification, which generally rely on more arbitrary scoring systems. However, the fractal dimension did not yield better age correlations than other previously described methods. At best, the results reflected the general observation that young adults below age 40 years...

  7. CT scanning of the paranasal sinuses: axial helical CT with reconstruction in the coronal direction versus coronal helical CT.

    Science.gov (United States)

    Bernhardt, T M; Rapp-Bernhardt, U; Fessel, A; Ludwig, K; Reichel, G; Grote, R

    1998-08-01

    Paranasal sinuses of 52 patients with sinusitis, tumours or fibrous dysplasia were scanned. Axially acquired spiral data were obtained and reconstructed coronally. Four radiologists compared the two sets of images. They evaluated the diagnostic quality for visualization of the ostiomeatal unit, infundibulum, infraorbital canal, inflammatory disease, fine osseous lamellae and presence of amalgam or step artefacts. Two test phantoms were scanned for both techniques and lens dose was measured. Statistical significant differences in the diagnostic quality of the representation of the fine osseous structures in the paranasal sinuses, attributable to step artefacts were found in the coronally reconstructed images (p < 0.001). However, there was no amalgam and almost no motion artefacts in the reconstructed images. Interobserver correlation was r = 0.953 versus 0.956 for inflammatory disease, r = 0.816 versus 0.852 for artefacts, and r = 0.596 versus 0.547 for fine osseous lamellae in coronally acquired or axially acquired and reconstructed images, respectively. Lens dose was measured between 11.8 mGy and 13.8 mGy for axially acquired and reconstructed images. The advantage of axially acquired, coronally reconstructed images is the absence of artefacts attributable to amalgam and fewer motion artefacts. Axially acquired, coronally reconstructed images are inferior to coronal helical CT images, because of step artefacts, when it comes to evaluating the resolution of fine osseous structures. Nevertheless, reconstructed images are suitable as a investigatory procedure for patients with inflammatory disease who cannot maintain the prone position.

  8. A Comparison of Plain Radiography with Computer Tomography in Determining Coronal and Sagittal Alignments following Total Knee Arthroplasty

    Directory of Open Access Journals (Sweden)

    Solayar GN

    2017-07-01

    Full Text Available INTRODUCTION: Optimal coronal and sagittal component positioning is important in achieving a successful outcome following total knee arthroplasty (TKA. Modalities to determine post-operative alignment include plain radiography and computer tomography (CT imaging. This study aims to determine the accuracy and reliability of plain radiographs in measuring coronal and sagittal alignment following TKA. MATERIALS AND METHODS: A prospective, consecutive study of 58 patients undergoing TKA was performed comparing alignment data from plain radiographs and CT imaging. Hip- knee-angle (HKA, sagittal femoral angle (SFA and sagittal tibial angle (STA measurements were taken by two observers from plain radiographs and compared with CT alignment. Intra- and inter-observer correlation was calculated for each measurement. RESULTS: Intra-observer correlation was excellent for HKA (r>0.89 with a mean difference of 0.95 and STA (r>0.8 compared to SFA (r=0.5. When comparing modalities (radiographs vs CT, HKA estimations for both observers showed the least maximum and mean differences while SFA observations were the least accurate. CONCLUSION: Radiographic estimation of HKA showed excellent intra- and inter-observer correlation and corresponds well with CT imaging. However, radiographic estimation of sagittal plane alignment was less reliably measured and correlated less with CT imaging. Plain radiography was found to be inferior to CT for estimation of biplanar prosthetic alignment following TKA.

  9. Standing sagittal alignment of the whole axial skeleton with reference to the gravity line in humans.

    Science.gov (United States)

    Hasegawa, Kazuhiro; Okamoto, Masashi; Hatsushikano, Shun; Shimoda, Haruka; Ono, Masatoshi; Homma, Takao; Watanabe, Kei

    2017-05-01

    Human beings stand upright with the chain of balance beginning at the feet, progressing to the lower limbs (ankles, knees, hip joints, pelvis), each of the spinal segments, and then ending at the cranium to achieve horizontal gaze and balance using minimum muscle activity. The details of the alignment and balance of the chain, however, are not clearly understood, due to the lack of information regarding the three-dimensional (3D) orientation of all bony elements in relation to the gravity line (GL). We performed a clinical study to clarify the standing sagittal alignment of whole axial skeletons in reference to the GL using the EOS slot-scanning 3D X-ray imaging system with simultaneous force plate measurement in a healthy human population. The GL was defined as a vertical line drawn through the centre of vertical pressure measured by the force plate. The present study yielded a complete set of physiological alignment measurements of the standing axial skeleton from the database of 136 healthy subjects (a mean age of 39.7 years, 20-69 years; men: 40, women: 96). The mean offset of centre of the acoustic meati from the GL was 0.0 cm. The offset of the cervical and thoracic vertebrae was posterior to the GL with the apex of thoracic kyphosis at T7, 5.0 cm posterior to the GL. The sagittal alignment changed to lordosis at the level of L2. The apex of the lumbar lordosis was L4, 0.6 cm anterior to the GL, and the centre of the base of the sacrum (CBS) was just posterior to the GL. The hip axis (HA) was 1.4 cm anterior to the GL. The knee joint was 2.4 cm posterior and the ankle joint was 4.8 cm posterior to the GL. L4-, L5- and the CBS-offset in subjects in the age decades of 40s, 50s and 60s were significantly posterior to those of subjects in their 20s. The L5- and CBS-offset in subjects in their 50s and 60s were also significantly posterior to those in subjects in their 30s. HA was never posterior to the GL. In the global alignment, there was a positive correlation

  10. Comparative Study between Axial and Coronal Planes of CT Enterography in Evaluation of Disease Activity and Complications of Crohn Disease

    International Nuclear Information System (INIS)

    Ahn, Sung Eun; Park, Seong Jin; Moon, Soung Kyung; Lim, Joo Won; Lee, Dong Ho; Ko, Young Tae; Kim, Hyo Jong

    2013-01-01

    To retrospectively compare the accuracy of axial and coronal planes of CT enterography for detection of pathologic findings of Crohn disease. 168 patients who were suspected of having Crohn disease underwent CT enterography. 66 patients who were diagnosed Crohn disease were retrospectively evaluated (endoscopic biopsy of terminal ileum: 12 patients, segmental resection of small bowel: 6 patients, diagnosed based on a combination of clinical, histopathological and imaging findings: 48 patients). 2 radiologists reviewed axial planes of CT enterography and one month later reviewed coronal planes. CT enterography findings of active phase, chronic phase and complications of Crohn disease were evaluated and then compared with axial and coronal planes by using chi-square test. Mucosal hyperenhancement, wall thickening, and mesenteric fat stranding were more detected on axial planes, which were CT findings of active Crohn disease. Pseudosacculation, fibrotic strictures, fistulas, abscesses were more detected on coronal planes, which were CT findings of chronic Crohn disease or complications. In particular, pseudosacculation and fibrotic strictures were significantly more detected on coronal planes. When evaluating CT enterography in Crohn disease, coronal planes provide more useful diagnostic information of pseudosacculation and fibrotic strictures.

  11. Role of coronal high-resolution diffusion-weighted imaging in acute optic neuritis: a comparison with axial orientation

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Ping [Zhongshan Hospital, Fudan University, Shanghai Institution of Medical Imaging, Shanghai (China); Eye and ENT Hospital of Fudan University, Department of Radiology, Shanghai (China); Sha, Yan; Wan, Hailin; Wang, Feng [Eye and ENT Hospital of Fudan University, Department of Radiology, Shanghai (China); Tian, Guohong [Eye and ENT Hospital of Fudan University, Department of Ophthalmology, Shanghai (China)

    2017-08-15

    Through a comparison with the axial orientation, we aimed to evaluate the role of coronal high-resolution diffusion-weighted imaging (DWI) in acute optic neuritis based on diagnostic accuracy and the reproducibility of apparent diffusion coefficient (ADC) measurements. Orbital DWI, using readout-segmented, parallel imaging, and 2D navigator-based reacquisition (RESOLVE-DWI), was performed on 49 patients with acute vision loss. The coronal (thickness = 3 mm) and axial (thickness = 2 mm) diffusion images were evaluated by two neuroradiologists retrospectively. The sensitivity, specificity, and accuracy were calculated through diagnostic test; the inter- and intra-observer reliabilities were assessed with a weighted Cohen's kappa test. In addition, the agreement of ADC measurement among observers was evaluated by the intra-class correlation coefficient (ICC), coefficient of variation (CV), and Bland-Altman plots. Comparison of ADC values was also performed by unpaired t test. Among the 49 patients, 47 clinically positive optic nerves and 51 clinically negative optic nerves were found. The sensitivity, specificity, and accuracy were 85.1/87.2%, 90.2/94.12%, and 87.8/90.8%, respectively, for coronal RESOLVE-DWI and 83.0/85.1%, 66.7/76.5%, and 75.5/79.6%, respectively, for axial RESOLVE-DWI. The inter-observer kappa values were 0.710 and 0.806 for axial and coronal RESOLVE-DWI, respectively, and the intra-observer kappa values were 0.822 and 0.909, respectively (each P < 0.0001). Regarding the reproducibility of ADC measurements on axial and coronal RESOLVE-DWI, the ICCs among observers were 0.846 and 0.941, respectively, and the CV values were 7.046 and 4.810%, respectively. Bland-Altman plots revealed smaller inter-observer variability on coronal RESOLVE-DWI. ADC values were significantly lower in positive group (each P < 0.0001). Higher specificity and better reproducibility of ADC measurements were found for coronal RESOLVE-DWI, which demonstrated the

  12. Influence of sagittal and axial types of ossification of posterior longitudinal ligament on mechanical stress in cervical spinal cord: A finite element analysis.

    Science.gov (United States)

    Khuyagbaatar, Batbayar; Kim, Kyungsoo; Park, Won Man; Kim, Yoon Hyuk

    2015-12-01

    There are few studies focusing on the prediction of stress distribution according to the types of ossification of the posterior longitudinal ligament, which can be fundamental information associated with clinical aspects such as the relationship between stress level and neurological symptom severity. In this study, the influence of sagittal and axial types of ossification of the posterior longitudinal ligament on mechanical stress in the cervical spinal cord was investigated. A three-dimensional finite element model of the cervical spine with spinal cord was developed and validated. The von Mises stresses in the cord and the reduction in cross-sectional areas and volume of the cord were investigated for various axial and sagittal types according to the occupying ratio of ossification of the posterior longitudinal ligament in the spinal canal. The influence of axial type was less than that of the sagittal type, even though the central type showed higher maximum stresses in the cord, especially for the continuous type. With a 60% occupying ratio of ossification of the posterior longitudinal ligament, the maximum stress was significantly high and the cross-sectional area of the spinal cord was reduced by more than 30% of the intact area regardless of sagittal or axial types. Finally, a higher level of sagittal extension would increase the peak cord tissue stress, which would be related to the neurological dysfunction and tissue damage. Quantitative investigation of biomechanical characteristics such as mechanical stress may provide fundamental information for pre-operative planning of treatment for ossification of the posterior longitudinal ligament. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Surgical management of coronal and sagittal imbalance of the spine without PSO: a multicentric cohort study on compensated adult degenerative deformities.

    Science.gov (United States)

    Ramieri, Alessandro; Miscusi, Massimo; Domenicucci, Maurizio; Raco, Antonino; Costanzo, Giuseppe

    2017-10-01

    Sagittal imbalance of severe adult degenerative deformities requires surgical correction to improve pain, mobility and quality of life. Our aim was a harmonic and balanced spine, treating a series of adult degenerative thoracolumbar and lumbar kyphoscoliosis by a non posterior subtraction osteotomy technique. We operated 22 painful thoracolumbar and lumbar compensated degenerative deformities by anterior (ALIF), extreme lateral (XLIF) and transforaminal (TLIF) interbody fusion and grade 2 osteotomy (SPO) to restore lumbar lordosis and mobilize the coronal curve. Two-stage surgery, first anterior and after 2 or 3 weeks posterior, was proposed when the Oswestry Disability Index (ODI) was equal to or greater than 50% and VAS more than 5. All patients were submitted to X-ray and clinical screening during pre, post-operative and follow-up periods. We performed 5 ALIFs, 39 XLIFs, 8 TLIFs, 32 SPOs. No major complications were recorded and complication rate was 18% after lateral fusion and 22.7% after posterior approach. Pelvic tilt, lumbar lordosis, sagittal vertical axis and thoracic kyphosis improved (p < 0.05). Clinical follow-up (mean 20.5; range 18-24) was satisfactory in all cases, except for two due to sacroiliac pain. Mean preoperative VAS was 7.7 (range 6-10), while ODI was 67% on average (range 50-78). After two-stage surgery, VAS and ODI decreased, respectively, to 2.4 (range 2-4) and 31% (range 25-45), while their values were 4 (range 2-6) and 35% (range 20-55) at the final follow-up. Current follow-up does not allow definitive conclusions. However, the surgical approach adopted in this study seems promising, improving balance and clinical condition of adult patients with a compensated sagittal degenerative imbalance of the thoracolumbar spine.

  14. Narrow CSF space at high convexity and high midline areas in idiopathic normal pressure hydrocephalus detected by axial and coronal MRI

    International Nuclear Information System (INIS)

    Sasaki, Makoto; Honda, Satoshi; Yuasa, Tatsuhiko; Iwamura, Akihide; Shibata, Eri; Ohba, Hideki

    2008-01-01

    The aim of this study was to determine the performance of axial and coronal magnetic resonance imaging (MRI) in detecting the narrowing of the cerebrospinal fluid (CSF) space at the high convexity and high midline areas, which is speculated to be one of the clinical characteristics of idiopathic normal pressure hydrocephalus (iNPH). We retrospectively examined axial and coronal T1-weighted images of 14 iNPH patients and 12 age-matched controls. The narrowness of the CSF space at the high convexity/midline was blindly evaluated by five raters using a continuous confidence rating scale for receiver operating characteristic (ROC) analysis. Axial and coronal imaging accurately determined the presence of the narrow cisterns/sulci at the high convexity/midline and was capable of predicting probable/definite iNPH with a high degree of accuracy. there were also no significant differences in the detection of this finding between the axial and coronal images. Both axial and coronal T1-weighted MRI can detect the narrow CSF space at the high convexity/midline accurately and may therefore facilitate clinicians in choosing a management strategy for iNPH patients. (orig.)

  15. Narrow CSF space at high convexity and high midline areas in idiopathic normal pressure hydrocephalus detected by axial and coronal MRI

    Energy Technology Data Exchange (ETDEWEB)

    Sasaki, Makoto [Iwate Medical University, Department of Radiology, Morioka (Japan); Honda, Satoshi [St. Luke' s International Hospital, Department of Radiology, Tokyo (Japan); Yuasa, Tatsuhiko; Iwamura, Akihide [Kohnodai Hospital, National Center of Neurology and Psychiatry, Department of Neurology, Ichikawa (Japan); Shibata, Eri [Iwate Medical University, Department of Neuropsychiatry, Morioka (Japan); Ohba, Hideki [Iwate Medical University, Department of Neurology, Morioka (Japan)

    2008-02-15

    The aim of this study was to determine the performance of axial and coronal magnetic resonance imaging (MRI) in detecting the narrowing of the cerebrospinal fluid (CSF) space at the high convexity and high midline areas, which is speculated to be one of the clinical characteristics of idiopathic normal pressure hydrocephalus (iNPH). We retrospectively examined axial and coronal T1-weighted images of 14 iNPH patients and 12 age-matched controls. The narrowness of the CSF space at the high convexity/midline was blindly evaluated by five raters using a continuous confidence rating scale for receiver operating characteristic (ROC) analysis. Axial and coronal imaging accurately determined the presence of the narrow cisterns/sulci at the high convexity/midline and was capable of predicting probable/definite iNPH with a high degree of accuracy. there were also no significant differences in the detection of this finding between the axial and coronal images. Both axial and coronal T1-weighted MRI can detect the narrow CSF space at the high convexity/midline accurately and may therefore facilitate clinicians in choosing a management strategy for iNPH patients. (orig.)

  16. Comparison of axial, coronal, and primary 3D review in MDCT colonography for the detection of small polyps: a phantom study

    NARCIS (Netherlands)

    Mang, Thomas; Schaefer-Prokop, Cornelia; Schima, Wolfgang; Maier, Andrea; Schober, Ewald; Mueller-Mang, Christina; Weber, Michael; Prokop, Mathias

    2009-01-01

    The purpose of this phantom study is to compare the influence of the reading technique (axial images alone in comparison to 3D endoluminal, coronal, and combined 2D/3D review methods) on the sensitivity and inter-reader variability with MDCT colonography for the detection of small colonic polyps. An

  17. Lumbosacral transitional vertebra and S1 radiculopathy: the value of coronal MR imaging

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    Bezuidenhout, Abraham Fourie; Lotz, Jan Willem [Stellenbosch University, Division of Radiodiagnosis, Department of Medical Imaging and Clinical Oncology, Faculty of Medicine and Health Sciences, Tygerberg (South Africa)

    2014-06-15

    The association of a lumbosacral transitional vertebra with accelerated degeneration of the disc above has been described. Lumbosacral transitional vertebrae have also been reported as a cause of extraforaminal entrapment of the L5 nerve root between the transverse segment of the transitional vertebra and the sacral ala optimally demonstrated by coronal MRI. The association of the lumbosacral transitional vertebra pseudoarthroses and S1 nerve root entrapment due to degenerative stenosis of the nerve root canal has never been described. We present 12 patients with lumbosacral transitional vertebrae that were referred for symptoms and signs of S1 nerve root radiculopathy in which the sagittal and axial MRI sequences failed to identify a plausible cause for the patients' S1 nerve root symptoms. A coronal T1-weighted imaging (T1WI) MRI sequence was consequently added to the investigation. The coronal T1WI MRI sequence demonstrated hypertrophic degenerative stenosis of the S1 nerve root canal at the level of the lumbosacral transitional vertebra pseudoarthrosis, with entrapment of the respective S1 nerve root in all patients. We emphasize the value of coronal T1WI MRI of the lumbosacral junction and sacrum if the cause for S1 radicular symptoms was not identified on conventional sagittal and axial MRI sequences in patients with lumbosacral transitional vertebrae. (orig.)

  18. Value of sagittal color Doppler ultrasonography as a supplementary tool in the differential diagnosis of fetal cleft lip and palate

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    Lee, Myoung Seok [Dept. of Radiology, Seoul Metropolitan Government-Seoul National University Boramae Medical Center, Seoul (Korea, Republic of); Cho, Jeong Yeon; Kim, Sang Youn; Kim, Seung Hyup [Dept. of Radiology, Seoul National University Hospital, Seoul (Korea, Republic of); Park, Joong Shin; Jun, Jong Kwan [College of Medicine, Seoul National University, Seoul (Korea, Republic of)

    2017-01-15

    The purpose of this study was to evaluate the feasibility and usefulness of sagittal color Doppler ultrasonography (CDUS) for the diagnosis of fetal cleft lip (CL) and cleft palate (CP). We performed targeted ultrasonography on 25 fetuses with CL and CP, taking coronal and axial images of the upper lip and maxillary alveolar arch in each case. The existence of defects in and malalignment of the alveolus on the axial image, hard palate defects on the midsagittal image, and flow-through defects on CDUS taken during fetal breathing or swallowing were assessed. We compared the ultrasonography findings with postnatal findings in all fetuses. Alveolar defects were detected in 16 out of 17 cases with CP and four out of eight cases with CL. Alveolar malalignment and hard palate defects were detected in 11 out of 17 cases and 14 out of 17 cases with CP, respectively, but not detected in any cases with CL. Communicating flow through the palate defect was detected in 11 out of 17 cases of CL with CP. The accuracy of detection in axial scans of an alveolar defect and malalignment was 80% and 76%, respectively. Accuracy of detection of in mid-sagittal images of hard palate defect and flow was 80% and 86%, respectively. The overall diagnostic accuracy of combined axial and sagittal images with sagittal CDUS was 92%. Sagittal CDUS of the fetal hard palate is a feasible method to directly reveal hard palate bony defects and flow through defects, which may have additional value in the differential diagnosis of fetal CL and CP.

  19. Value of sagittal color Doppler ultrasonography as a supplementary tool in the differential diagnosis of fetal cleft lip and palate

    International Nuclear Information System (INIS)

    Lee, Myoung Seok; Cho, Jeong Yeon; Kim, Sang Youn; Kim, Seung Hyup; Park, Joong Shin; Jun, Jong Kwan

    2017-01-01

    The purpose of this study was to evaluate the feasibility and usefulness of sagittal color Doppler ultrasonography (CDUS) for the diagnosis of fetal cleft lip (CL) and cleft palate (CP). We performed targeted ultrasonography on 25 fetuses with CL and CP, taking coronal and axial images of the upper lip and maxillary alveolar arch in each case. The existence of defects in and malalignment of the alveolus on the axial image, hard palate defects on the midsagittal image, and flow-through defects on CDUS taken during fetal breathing or swallowing were assessed. We compared the ultrasonography findings with postnatal findings in all fetuses. Alveolar defects were detected in 16 out of 17 cases with CP and four out of eight cases with CL. Alveolar malalignment and hard palate defects were detected in 11 out of 17 cases and 14 out of 17 cases with CP, respectively, but not detected in any cases with CL. Communicating flow through the palate defect was detected in 11 out of 17 cases of CL with CP. The accuracy of detection in axial scans of an alveolar defect and malalignment was 80% and 76%, respectively. Accuracy of detection of in mid-sagittal images of hard palate defect and flow was 80% and 86%, respectively. The overall diagnostic accuracy of combined axial and sagittal images with sagittal CDUS was 92%. Sagittal CDUS of the fetal hard palate is a feasible method to directly reveal hard palate bony defects and flow through defects, which may have additional value in the differential diagnosis of fetal CL and CP

  20. Three-dimensional axial volume acquisition on meniscal lesions of the knee

    Energy Technology Data Exchange (ETDEWEB)

    Araki, Yutaka; Ootani, Masatoshi; Furukawa, Tomoaki; Yamamoto, Tadatsuka; Tomoda, Kaname; Tsukaguchi, Isao (Osaka Rosai Hospital, Sakai (Japan)); Mitomo, Masanori

    1991-12-01

    Axial three-dimensional volume scans obtained by magnetic resonance (MR) imaging were used to evaluate meniscal lesions of the knee in 28 knees of 26 cases. Axial 0.7 mm thin-sliced images with volume scan outlined the overall meniscal appearance for the first time. Axial volume scan was essential to the diagnosis of discoid lateral meniscus because only it could depict the characteristic elongated appearance of discoid lateral meniscus. Radial meniscal tears were depicted only by this technique: conventional sagittal and coronal views could not detect this type of meniscal tear. Volume scan could detect the precise extent of lesions with horizontal meniscal tears and meniscal degeneration. These MR findings obtained by axial volume scans were confirmed by arthroscopy in all cases. We concluded that volume scans were extremely useful in the evaluation of meniscal lesions because they offered axial views that provided much information on menisci located horizontally in the knee. (author).

  1. Three-dimensional axial volume acquisition on meniscal lesions of the knee

    International Nuclear Information System (INIS)

    Araki, Yutaka; Ootani, Masatoshi; Furukawa, Tomoaki; Yamamoto, Tadatsuka; Tomoda, Kaname; Tsukaguchi, Isao; Mitomo, Masanori.

    1991-01-01

    Axial three-dimensional volume scans obtained by magnetic resonance (MR) imaging were used to evaluate meniscal lesions of the knee in 28 knees of 26 cases. Axial 0.7 mm thin-sliced images with volume scan outlined the overall meniscal appearance for the first time. Axial volume scan was essential to the diagnosis of discoid lateral meniscus because only it could depict the characteristic elongated appearance of discoid lateral meniscus. Radial meniscal tears were depicted only by this technique: conventional sagittal and coronal views could not detect this type of meniscal tear. Volume scan could detect the precise extent of lesions with horizontal meniscal tears and meniscal degeneration. These MR findings obtained by axial volume scans were confirmed by arthroscopy in all cases. We concluded that volume scans were extremely useful in the evaluation of meniscal lesions because they offered axial views that provided much information on menisci located horizontally in the knee. (author)

  2. Importance of sagittal MR imaging in nontraumatic femoral head osteonecrosis in children

    Energy Technology Data Exchange (ETDEWEB)

    Ha, Alice S. [Hospital of the University of Pennsylvania, Department of Radiology, Philadelphia, PA (United States); Wells, Lawrence [Children' s Hospital of Philadelphia, Department of Orthopedic Surgery, Philadelphia, PA (United States); Jaramillo, Diego [Children' s Hospital of Philadelphia, Department of Radiology, Philadelphia, PA (United States)

    2008-11-15

    In nontraumatic femoral head osteonecrosis, characterization of femoral head collapse is important in staging disease progression and planning treatment. Few prior studies have quantitatively compared the ability of sagittal and coronal MR images to detect femoral head collapse. We hypothesized that sagittal MR images show a greater degree and angular span of femoral head collapse than coronal images. We reviewed 38 hip MRI scans of nontraumatic femoral head osteonecrosis from 34 pediatric patients. In both sagittal and coronal images, the maximal extent and angular location along with the angular span of the femoral head collapse were measured. Differences were evaluated using a paired t-test. The extent of bone and cartilage loss from the femoral head was evaluated. Sagittal MR images showed 29% maximal femoral head radius collapse, whereas coronal images showed 16% collapse (P<0.001). Sagittal images showed a larger angular span of collapse (115 ) than coronal images (55 , P<0.001). Sagittal images showed greater epiphyseal bone loss in the anterior than in the posterior portion (P<0.001), whereas coronal images did not show a significant difference in bone loss between the medial and lateral portion (P=0.32). Sagittal images show greater femoral head collapse than coronal images in nontraumatic femoral head osteonecrosis. (orig.)

  3. Importance of sagittal MR imaging in nontraumatic femoral head osteonecrosis in children

    International Nuclear Information System (INIS)

    Ha, Alice S.; Wells, Lawrence; Jaramillo, Diego

    2008-01-01

    In nontraumatic femoral head osteonecrosis, characterization of femoral head collapse is important in staging disease progression and planning treatment. Few prior studies have quantitatively compared the ability of sagittal and coronal MR images to detect femoral head collapse. We hypothesized that sagittal MR images show a greater degree and angular span of femoral head collapse than coronal images. We reviewed 38 hip MRI scans of nontraumatic femoral head osteonecrosis from 34 pediatric patients. In both sagittal and coronal images, the maximal extent and angular location along with the angular span of the femoral head collapse were measured. Differences were evaluated using a paired t-test. The extent of bone and cartilage loss from the femoral head was evaluated. Sagittal MR images showed 29% maximal femoral head radius collapse, whereas coronal images showed 16% collapse (P<0.001). Sagittal images showed a larger angular span of collapse (115 ) than coronal images (55 , P<0.001). Sagittal images showed greater epiphyseal bone loss in the anterior than in the posterior portion (P<0.001), whereas coronal images did not show a significant difference in bone loss between the medial and lateral portion (P=0.32). Sagittal images show greater femoral head collapse than coronal images in nontraumatic femoral head osteonecrosis. (orig.)

  4. Morphological study of the axial view of the cervical spinal cord by MR images

    International Nuclear Information System (INIS)

    Suzuki, Masahiro; Shimamura, Tadashi

    1994-01-01

    To investigate the morphological changes in the cervical spinal cord in patients with cervical myelopathy, we examined the axial anatomy of the cervical spinal cord and the spinal canal using MRI and CT scans. This study involved 35 patients (mean age=56.8) with cervical myelopathy and 118 adult normal volunteers (mean age=48.1) as controls. The transverse area of the spinal cord was measured on MR images (T 1 images), while the transverse area of the spinal canal was measured on CT. In normal subjects, the transverse area, the sagittal diameter, and the coronal diameter of the spinal cord showed a significant positive correlation with body height, and a significant negative correlation with age. No significant difference was identified between males and females. The transverse area, the sagittal diameter, the coronal diameter, and the ratio of the sagittal/coronal diameter of the spinal cord and the spinal canal showed significant positive correlations among each other in normal subjects, but no significant correlation was noted in the patients with cervical myelopathy. These was no significant difference between the normal subjects and the patients in the transverse area or in the ratio of the sagittal/coronal diameter of the spinal cord at the levels without cord compression. However, the transverse area of the spinal canal in the patients with myelopathy was significantly smaller than that of normal subjects. In conclusion, a poor or no correlation between the size of the spinal cord and the spinal canal is a frequent finding in patients with myelopathy. Furthermore, this study suggests that patients with myelopathy present a narrow spinal canal more frequently than do normal subjects. (author)

  5. CHANGES IN THE SAGITTAL BALANCE IN CONGENITAL SCOLIOSIS CORRECTION SURGERY

    OpenAIRE

    Mancuso Filho, José Antonio; Borges, Paulo Alvim; Tsuchiya, Eduardo Hideo; Letaif, Olavo Biraghi; Marcon, Raphael Martus; Cristante, Alexandre Fogaça

    2016-01-01

    ABSTRACT Objective: This study aimed to determine whether surgery leads to changes in sagittal balance in patients with congenital scoliosis. Methods: We retrospectively reviewed all cases of scoliosis operated in a tertiary hospital between January 2009 and January 2013. In all cases the deformity in the coronal and sagittal planes, kyphosis, and lordosis were measured, using the Cobb method, and spinopelvic parameters: pelvic incidence (PI), sacral slope (SS), and pelvic tilt (PT). Resul...

  6. MR imaging of the anterior cruciate ligament. Value of thin slice direct oblique coronal technique

    Energy Technology Data Exchange (ETDEWEB)

    Katahira, Kazuhiro; Yamashita, Yasuyuki; Takahashi, Mutsumasa [Kumamoto Univ. (Japan). School of Medicine; Otsuka, Nobuko; Koga, Yukunori; Fukumoto, Tetsuya; Nomura, Kazutoshi

    2001-02-01

    The value of the thin slice direct oblique coronal technique, which is parallel to the anterior cruciate ligament (ACL), was assessed in the evaluation of ACL injury in comparison with conventional oblique sagittal and coronal images. A thin slice direct oblique coronal technique was developed and applied clinically to 62 patients after conventional oblique sagittal and coronal images had been obtained. MR images of these 62 patients (24 with tears and 38 without tears) with an arthroscopic correlation were evaluated by three radiologists who were unaware of the arthroscopic results. The diagnostic accuracy of these new images was compared with that of oblique sagittal and coronal images by ROC analysis. Conventional oblique sagittal and coronal images for the diagnosis of ACL tears revealed accuracies of 82%, 84%, and 84%, sensitivities of 92%, 92%, and 96% and specificities of 76%, 79%, and 76% for the three reviewers, respectively. On thin slice direct oblique coronal images, specificities of 97%, 97%, and 97%, sensitivities of 96%, 96%, and 96%, and accuracies of 97%, 97%, and 97% were obtained, respectively. Diagnostic ability was significantly better with direct oblique coronal images (mean area under the ROC curve [Az]=0.99) than with conventional oblique sagittal and coronal images (Az=0.91) (p<0.05). The addition of thin slice direct oblique coronal images significantly improved specificity and accuracy in the diagnosis of ACL tears. (author)

  7. PONDEROMOTIVE ACCELERATION IN CORONAL LOOPS

    Energy Technology Data Exchange (ETDEWEB)

    Dahlburg, R. B.; Obenschain, K. [LCP and FD, Naval Research Laboratory, Washington, DC 20375 (United States); Laming, J. M. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States); Taylor, B. D. [AFRL Eglin AFB, Pensacola, FL 32542 (United States)

    2016-11-10

    Ponderomotive acceleration has been asserted to be a cause of the first ionization potential (FIP) effect, the well-known enhancement in abundance by a factor of 3–4 over photospheric values of elements in the solar corona with FIP less than about 10 eV. It is shown here by means of numerical simulations that ponderomotive acceleration occurs in solar coronal loops, with the appropriate magnitude and direction, as a “by-product” of coronal heating. The numerical simulations are performed with the HYPERION code, which solves the fully compressible three-dimensional magnetohydrodynamic equations including nonlinear thermal conduction and optically thin radiation. Numerical simulations of coronal loops with an axial magnetic field from 0.005 to 0.02 T and lengths from 25,000 to 75,000 km are presented. In the simulations the footpoints of the axial loop magnetic field are convected by random, large-scale motions. There is a continuous formation and dissipation of field-aligned current sheets, which act to heat the loop. As a consequence of coronal magnetic reconnection, small-scale, high-speed jets form. The familiar vortex quadrupoles form at reconnection sites. Between the magnetic footpoints and the corona the reconnection flow merges with the boundary flow. It is in this region that the ponderomotive acceleration occurs. Mirroring the character of the coronal reconnection, the ponderomotive acceleration is also found to be intermittent.

  8. Coronal magnetometry

    CERN Document Server

    Zhang, Jie; Bastian, Timothy

    2014-01-01

    This volume is a collection of research articles on the subject of the solar corona, and particularly, coronal magnetism. The book was motivated by the Workshop on Coronal Magnetism: Connecting Models to Data and the Corona to the Earth, which was held 21 - 23 May 2012 in Boulder, Colorado, USA. This workshop was attended by approximately 60 researchers. Articles from this meeting are contained in this topical issue, but the topical issue also contains contributions from researchers not present at the workshop. This volume is aimed at researchers and graduate students active in solar physics. Originally published in Solar Physics, Vol. 288, Issue 2, 2013 and Vol. 289, Issue 8, 2014.

  9. 3.0T MR imaging of the ankle: Axial traction for morphological cartilage evaluation, quantitative T2 mapping and cartilage diffusion imaging-A preliminary study.

    Science.gov (United States)

    Jungmann, Pia M; Baum, Thomas; Schaeffeler, Christoph; Sauerschnig, Martin; Brucker, Peter U; Mann, Alexander; Ganter, Carl; Bieri, Oliver; Rummeny, Ernst J; Woertler, Klaus; Bauer, Jan S

    2015-08-01

    To determine the impact of axial traction during high resolution 3.0T MR imaging of the ankle on morphological assessment of articular cartilage and quantitative cartilage imaging parameters. MR images of n=25 asymptomatic ankles were acquired with and without axial traction (6kg). Coronal and sagittal T1-weighted (w) turbo spin echo (TSE) sequences with a driven equilibrium pulse and sagittal fat-saturated intermediate-w (IMfs) TSE sequences were acquired for morphological evaluation on a four-point scale (1=best, 4=worst). For quantitative assessment of cartilage degradation segmentation was performed on 2D multislice-multiecho (MSME) SE T2, steady-state free-precession (SSFP; n=8) T2 and SSFP diffusion-weighted imaging (DWI; n=8) images. Wilcoxon-tests and paired t-tests were used for statistical analysis. With axial traction, joint space width increased significantly and delineation of cartilage surfaces was rated superior (Pw images (P0.05). T2 values were lower at the tibia than at the talus (P<0.001). Reproducibility was better for images with axial traction. Axial traction increased the joint space width, allowed for better visualization of cartilage surfaces and improved compartment discrimination and reproducibility of quantitative cartilage parameters. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  10. Coronal Holes

    Directory of Open Access Journals (Sweden)

    Steven R. Cranmer

    2009-09-01

    Full Text Available Coronal holes are the darkest and least active regions of the Sun, as observed both on the solar disk and above the solar limb. Coronal holes are associated with rapidly expanding open magnetic fields and the acceleration of the high-speed solar wind. This paper reviews measurements of the plasma properties in coronal holes and how these measurements are used to reveal details about the physical processes that heat the solar corona and accelerate the solar wind. It is still unknown to what extent the solar wind is fed by flux tubes that remain open (and are energized by footpoint-driven wave-like fluctuations, and to what extent much of the mass and energy is input intermittently from closed loops into the open-field regions. Evidence for both paradigms is summarized in this paper. Special emphasis is also given to spectroscopic and coronagraphic measurements that allow the highly dynamic non-equilibrium evolution of the plasma to be followed as the asymptotic conditions in interplanetary space are established in the extended corona. For example, the importance of kinetic plasma physics and turbulence in coronal holes has been affirmed by surprising measurements from the UVCS instrument on SOHO that heavy ions are heated to hundreds of times the temperatures of protons and electrons. These observations point to specific kinds of collisionless Alfvén wave damping (i.e., ion cyclotron resonance, but complete theoretical models do not yet exist. Despite our incomplete knowledge of the complex multi-scale plasma physics, however, much progress has been made toward the goal of understanding the mechanisms ultimately responsible for producing the observed properties of coronal holes.

  11. Measurement accuracy of condylar position on reformatted sagittal CT and sagittal tomography

    Energy Technology Data Exchange (ETDEWEB)

    Hiruma, Takayoshi [Showa Univ., Tokyo (Japan). School of Dentistry

    1995-12-01

    The purpose of this study was to compare the measurement accuracy of the condylar position on reformatted sagittal CT with that on sagittal tomography (TG). The CTs were reformatted from the 1 mm thickness/interval coronal scan. The TGs were performed with hypocycloidal motion. Impressions of the joint space were taken in order to estimate the actual dimensions. The errors, differences between the values from the impressions and the values from CTs and TGs, were calculated and analyzed by ANOVA. The results were as follows: The mean measurement error of the condylar position on the CT was 0.1 mm. No statistically significant differences were observed among the CTs reformatted from the coronal scan obtained with the X-ray beam projecting at 90deg, 80deg and 70deg to the F-H plane. The measurement error on the TGs with a mean value of 0.3 mm was larger than that of the CTs. However, one of the 6 TMJs caused a great measurement error on the TG with a mean value of 0.9 mm while the measurement of the other 5 TMJs showed a smaller mean error of 0.1 mm. These findings suggest that the anatomic morphology of TMJs influence the measurement accuracy on the TGs. (author).

  12. Coronal ultra-thick multiplanar CT reconstructions (MPR) of the pelvis in the multiple trauma patient: an alternative for the initial conventional radiograph

    International Nuclear Information System (INIS)

    Leschka, S.; Alkadhi, H.; Boehm, T.; Marincek, B.; Wildermuth, S.

    2005-01-01

    Purpose: multiple trauma patients with clinically suspected pelvic fractures often directly undergo a CT scan. However, the initial portable pelvis film (PPF) for further follow-up is then not available. This study examines whether coronal ultra-thick multiplanar reconstructions from CT data are similar when compared with the initial PPF, thus having the potential to serve as an alternative baseline image. Materials and methods: initial PPF and coronal ultra-thick multiplanar CT reconstructions of 33 multiple trauma patients with pelvic fractures were retrospectively analyzed by two independent radiologists with regard to image quality, visualization of anatomical landmarks, and diagnostic accuracy. The primary diagnosis of pelvic fractures was made by using thin axial CT images and thin slice coronal and sagittal reconstructions and served as the standard of reference. Results: coronal ultra-thick multiplanar CT reconstructions were superior to PPF regarding image adjustment (p < 0.02), absence of overlaying structures (p < 0.05), and overall image quality (p < 0.01). Visualization of most anatomical landmarks was similar with both modalities, except of the iliosacral joint and acetabular lines which were more accurately depicted on ultrathick multiplanar CT reconstructions (p < 0.05). Diagnostic accuracy of coronal ultra-thick CT reconstructions was similar to PPF regarding most fracture types, except of a higher accuracy of coronal ultra-thick CT reconstructions for iliosacral joint and acetabular column fractures (p < 0.05). Conclusion: coronal ultrathick multiplanar CT reconstructions of the pelvis provide similar image quality and diagnostic accuracy compared to PPF and are therefore suited as alternative baseline image in multiple trauma patients who directly undergo CT. (orig.)

  13. Back to the future: sagittal CT in the evaluation of COPD

    International Nuclear Information System (INIS)

    Hightower, Jessica S.; Amadi, Chiemezie; Den, Elana; Schmitt, James E.; Shah, Rosita M.; Miller, Wallace T.

    2016-01-01

    To identify features of obstructive airway disease on sagittal reconstruction, compare the accuracy of findings to traditional imaging characteristics of COPD, and determine the fraction of additional cases identified using new characteristics. The study was approved by the centre's Institutional Review Board and is HIPAA compliant. Two hundred sixteen patients with HRCT and spirometry within a 3-month window were included. Four radiologists evaluated each HRCT for traditional characteristics of COPD and new quantitative and qualitative features of obstruction on axial and sagittal reconstructions. Imaging characteristics were assessed for correlation with the spirometric diagnosis of obstructive airway disease. Quantitative and qualitative findings on sagittal reconstruction are highly specific for COPD (specificity >90 %). Features of hyperinflation on sagittal reconstruction are more accurate predictors of obstruction than traditional axial measures, with greater interobserver reliability (hyperinflation left hemidiaphragm: accuracy: 70.08 % ± 2.49 %; kappa: 0.511 versus traditional measures: accuracy: 62.00 % ± 5.38 %; kappa: 0.407). Sagittal reconstruction identified 27-70 % more patients with COPD than traditional axial findings (p < 0.05). Analysis of sagittal reconstruction enables greater accuracy and specificity in the diagnosis of obstructive airway disease compared to traditional measures on axial imaging. Use of sagittal reconstructions can help identify up to 70 % more patients with COPD than traditional imaging findings alone. (orig.)

  14. Estimation of ocular volume from axial length.

    Science.gov (United States)

    Nagra, Manbir; Gilmartin, Bernard; Logan, Nicola S

    2014-12-01

    To determine which biometric parameters provide optimum predictive power for ocular volume. Sixty-seven adult subjects were scanned with a Siemens 3-T MRI scanner. Mean spherical error (MSE) (D) was measured with a Shin-Nippon autorefractor and a Zeiss IOLMaster used to measure (mm) axial length (AL), anterior chamber depth (ACD) and corneal radius (CR). Total ocular volume (TOV) was calculated from T2-weighted MRIs (voxel size 1.0 mm(3)) using an automatic voxel counting and shading algorithm. Each MR slice was subsequently edited manually in the axial, sagittal and coronal plane, the latter enabling location of the posterior pole of the crystalline lens and partitioning of TOV into anterior (AV) and posterior volume (PV) regions. Mean values (±SD) for MSE (D), AL (mm), ACD (mm) and CR (mm) were -2.62±3.83, 24.51±1.47, 3.55±0.34 and 7.75±0.28, respectively. Mean values (±SD) for TOV, AV and PV (mm(3)) were 8168.21±1141.86, 1099.40±139.24 and 7068.82±1134.05, respectively. TOV showed significant correlation with MSE, AL, PV (all p<0.001), CR (p=0.043) and ACD (p=0.024). Bar CR, the correlations were shown to be wholly attributable to variation in PV. Multiple linear regression indicated that the combination of AL and CR provided optimum R(2) values of 79.4% for TOV. Clinically useful estimations of ocular volume can be obtained from measurement of AL and CR. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  15. 3.0 T MR imaging of the ankle: Axial traction for morphological cartilage evaluation, quantitative T2 mapping and cartilage diffusion imaging—A preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Jungmann, Pia M., E-mail: pia.jungmann@tum.de [Department of Radiology, Klinikum rechts der Isar, Technische Universitaet Muenchen, Ismaninger Strasse 22, 81675 Munich (Germany); Baum, Thomas, E-mail: thomas.baum@tum.de [Department of Radiology, Klinikum rechts der Isar, Technische Universitaet Muenchen, Ismaninger Strasse 22, 81675 Munich (Germany); Schaeffeler, Christoph, E-mail: schaeffeler@me.com [Department of Radiology, Klinikum rechts der Isar, Technische Universitaet Muenchen, Ismaninger Strasse 22, 81675 Munich (Germany); Musculoskeletal Imaging, Kantonsspital Graubuenden, Loestrasse 170, CH-7000 Chur (Switzerland); Sauerschnig, Martin, E-mail: martin.sauerschnig@mri.tum.de [Department of Trauma Surgery, Klinikum rechts der Isar, Technische Universitaet Muenchen, Ismaninger Strasse 22, 81675 Munich (Germany); Department of Orthopaedic Sports Medicine, Klinikum rechts der Isar, Technische Universitaet Muenchen, Ismaninger Strasse 22, 81675 Munich (Germany); Brucker, Peter U., E-mail: peter.brucker@lrz.tu-muenchen.de [Department of Orthopaedic Sports Medicine, Klinikum rechts der Isar, Technische Universitaet Muenchen, Ismaninger Strasse 22, 81675 Munich (Germany); Mann, Alexander, E-mail: abmann@onlinemed.de [Department of Radiology, Klinikum rechts der Isar, Technische Universitaet Muenchen, Ismaninger Strasse 22, 81675 Munich (Germany); Department of Orthopaedic Sports Medicine, Klinikum rechts der Isar, Technische Universitaet Muenchen, Ismaninger Strasse 22, 81675 Munich (Germany); Ganter, Carl, E-mail: cganter@tum.de [Department of Radiology, Klinikum rechts der Isar, Technische Universitaet Muenchen, Ismaninger Strasse 22, 81675 Munich (Germany); Bieri, Oliver, E-mail: oliver.bieri@unibas.ch [Division of Radiological Physics, Department of Radiology, University of Basel Hospital, Petersgraben 4, 4031 Basel (Switzerland); and others

    2015-08-15

    Highlights: • Axial traction is applicable during high resolution MR imaging of the ankle. • Axial traction during MR imaging oft the ankle improves cartilage surface delineation of the individual tibial and talar cartilage layer for better morphological evaluation without the need of intraarticular contrast agent application. • Coronal T1-weighted MR images with a driven equilibrium pulse performed best. • Axial traction during MR imaging of the ankle facilitates compartment discrimination for segmentation purposes resulting in better reproducibility. - Abstract: Purpose: To determine the impact of axial traction during high resolution 3.0 T MR imaging of the ankle on morphological assessment of articular cartilage and quantitative cartilage imaging parameters. Materials and Methods: MR images of n = 25 asymptomatic ankles were acquired with and without axial traction (6 kg). Coronal and sagittal T1-weighted (w) turbo spin echo (TSE) sequences with a driven equilibrium pulse and sagittal fat-saturated intermediate-w (IMfs) TSE sequences were acquired for morphological evaluation on a four-point scale (1 = best, 4 = worst). For quantitative assessment of cartilage degradation segmentation was performed on 2D multislice-multiecho (MSME) SE T2, steady-state free-precession (SSFP; n = 8) T2 and SSFP diffusion-weighted imaging (DWI; n = 8) images. Wilcoxon-tests and paired t-tests were used for statistical analysis. Results: With axial traction, joint space width increased significantly and delineation of cartilage surfaces was rated superior (P < 0.05). Cartilage surfaces were best visualized on coronal T1-w images (P < 0.05). Differences for cartilage matrix evaluation were smaller. Subchondral bone evaluation, motion artifacts and image quality were not significantly different between the acquisition methods (P > 0.05). T2 values were lower at the tibia than at the talus (P < 0.001). Reproducibility was better for images with axial traction. Conclusion

  16. Usefulness of curved coronal MPR imaging for the diagnosis of cervical radiculopathy

    International Nuclear Information System (INIS)

    Inukai, Chikage; Inukai, Takashi; Matsuo, Naoki; Goto, Hisaharu; Takagi, Teruhide; Takayasu, Masakazu; Shimizu, Ikuo

    2010-01-01

    In surgical treatment of cervical radiculopathy, localization of the responsible lesions by various imaging modalities is essential. Among them, MRI is non-invasive and plays a primary role in the assessment of spinal radicular symptoms. However, demonstration of nerve root compression is sometimes difficult by the conventional methods of MRI, such as T1 weighted (T1W) and T2 weighted (T2W) sagittal or axial images. We have applied a new technique of curved coronal multiplanar reconstruction (MPR) imaging for the diagnosis of cervical radiculopathy. Ten patients (4 male, 6 female) with ages between 31 and 79 year-old, who had clinical diagnosis of cervical radiculopathy, were included in this study. Seven patients underwent anterior key-hole foraminotomy to decompress the nerve root with successful results. All the patients had 3D MRI studies, such as true fast imaging with steady-state precession (FISP), 3DT2W sampling perfection with application optimized contrasts using different fillip angle evolution (SPACE), and 3D multi-echo data image combination (MEDIC) imagings in addition to the routine MRI (1.5 T Avanto, Siemens, Germany) with a phased array coil. The curved coronal MPR images were produced from these MRI data using a workstation. The nerve root compression was diagnosed by curved coronal MPR images in all the patients. The compression sites were compatible with those of the operative findings in 7 patients, who underwent surgical treatment. The MEDIC imagings were the most demonstrable to visualize the nerve root, while the 3D-space imagings were the next. The curved coronal MPR imaging is useful for the diagnosis of accurate localization of the compressing lesions in patients with cervical radiculopathy. (author)

  17. Diagnostic value of multidetector row CT in rectal cancer staging: comparison of multiplanar and axial images with histopathology

    International Nuclear Information System (INIS)

    Sinha, R.; Verma, R.; Rajesh, A.; Richards, C.J.

    2006-01-01

    Aim: Although magnetic resonance (MR) imaging is widely used for rectal cancer staging, many centres in the UK perform computed tomography (CT) for staging rectal cancer at present. Furthermore in a small proportion of cases contraindications to MR imaging may lead to staging using CT. The purpose of this study was to evaluate the accuracy of current generation multidetector row CT (MDCT) in local staging of rectal cancer. In particular the accuracy of multiplanar (MPR) versus axial images in the staging of rectal cancer was assessed. Material and methods: Sixty-nine consecutive patients were identified who had undergone staging of rectal cancer on CT. The imaging data were reviewed as axial images and then as MPR images (coronal and sagittal) perpendicular and parallel to the tumour axis. CT staging on axial and MPR images was then compared to histopathological staging. Results: MPR images detected more T4 and T3 stage tumours than axial images alone. The overall accuracy of T-staging on MPR images was 87.1% versus 73.0% for axial images alone. The overall accuracy of N staging on MPR versus axial images was 84.8% versus 70.7%. There was a statistically significant difference in the staging of T3 tumours between MPR and axial images (p < 0.001). Conclusion: Multidetector row CT has high accuracy for local staging of rectal cancer. Addition of MPR images to standard axial images provides higher accuracy rates for T and N staging of rectal cancer than axial images alone

  18. Relationship between facet tropism and facet joint degeneration in the sub-axial cervical spine

    Directory of Open Access Journals (Sweden)

    Xin Rong

    2017-02-01

    Full Text Available Abstract Background Facet tropism is the angular asymmetry between the left and right facet joint orientation. Although debatable, facet tropism was suggested to be associated with disc degeneration, facet degeneration and degenerative spondylolisthesis in the lumbar spine. The purpose of this study was to explore the relationship between facet tropism and facet degeneration in the sub-axial cervical spine. Methods A total of 200 patients with cervical spondylosis were retrospectively analyzed. Facet degeneration was categorized into 4 grade: grade I, normal; grade II, degenerative changes including joint space narrowing, cyst formation, small osteophytes (3 mm without fusion of the joint; grade IV, bony fusion of the facet joints. Facet orientations and facet tropisms with respect to the transverse, sagittal and coronal plane were calculated from the reconstructed cervical spine, which was based on the axial CT scan images. The paired facet joints were then categorized into three types: symmetric, moderated tropism and severe tropism. Univariate and multivariate analysis were performed to evaluate the relationship between any demographic and anatomical factor and facet degeneration. Results The mean age of enrolled patients was 46.23 years old (ranging from 30 to 64 years old. There were 114 males and 86 females. The degrees of facet degeneration varied according to cervical levels and ages. Degenerated facet joints were most common at C2-C3 level and more common in patients above 50 years old. The facet orientations were also different from level to level. By univariate analysis, genders, ages, cervical levels, facet orientations and facet tropisms were all significantly different between the normal facets and degenerated facets. However, results from multivariate logistic regression suggested only age and facet tropism with respect to the sagittal plane were related to facet degeneration. Conclusion Facet degeneration were more common at

  19. Relationship between facet tropism and facet joint degeneration in the sub-axial cervical spine.

    Science.gov (United States)

    Rong, Xin; Liu, Ziyang; Wang, Beiyu; Pan, Xuelin; Liu, Hao

    2017-02-20

    Facet tropism is the angular asymmetry between the left and right facet joint orientation. Although debatable, facet tropism was suggested to be associated with disc degeneration, facet degeneration and degenerative spondylolisthesis in the lumbar spine. The purpose of this study was to explore the relationship between facet tropism and facet degeneration in the sub-axial cervical spine. A total of 200 patients with cervical spondylosis were retrospectively analyzed. Facet degeneration was categorized into 4 grade: grade I, normal; grade II, degenerative changes including joint space narrowing, cyst formation, small osteophytes (3 mm) without fusion of the joint; grade IV, bony fusion of the facet joints. Facet orientations and facet tropisms with respect to the transverse, sagittal and coronal plane were calculated from the reconstructed cervical spine, which was based on the axial CT scan images. The paired facet joints were then categorized into three types: symmetric, moderated tropism and severe tropism. Univariate and multivariate analysis were performed to evaluate the relationship between any demographic and anatomical factor and facet degeneration. The mean age of enrolled patients was 46.23 years old (ranging from 30 to 64 years old). There were 114 males and 86 females. The degrees of facet degeneration varied according to cervical levels and ages. Degenerated facet joints were most common at C2-C3 level and more common in patients above 50 years old. The facet orientations were also different from level to level. By univariate analysis, genders, ages, cervical levels, facet orientations and facet tropisms were all significantly different between the normal facets and degenerated facets. However, results from multivariate logistic regression suggested only age and facet tropism with respect to the sagittal plane were related to facet degeneration. Facet degeneration were more common at C2-C3 level. Older age and facet tropism with respect to the

  20. Value of the coronal plane in MRI of internal derangement of the knee

    International Nuclear Information System (INIS)

    Haramati, N.; Staron, R.B.; Cushin, S.; Nickoloff, E.L.; Feldmann, F.

    1994-01-01

    Sagittal images usually receive the most scrutiny in the magnetic resonance evaluation of meniscal and anterior cruciate ligament tears. We assessed the relative contribution of the coronal view. All knee magnetic resonance examinations performed over a 2-year period that had surgical confirmation were reviewed with respect to the presence of meniscal and anterior cruciate ligament tears. The appearance of an attenuated but uninterrupted anterior cruciate ligament was also evaluated. The coronal and sagittal plane images were evaluated separately. The study included 68 medial menisci, 67 lateral menisci, and 71 anterior cruciate ligaments. The coronal view is especially useful in the evaluation of the laterial meniscus. An anterior cruciate ligament that appears attennated but uninterrupted should be considered intact. The anterior cruciate ligament may be evaluated on the coronal view. The coronal view should be regarded as similar to the lateral chest radiograph, which supplements, but does not replace, the frontal chest radiograph. (orig.)

  1. The accuracy of intramedullary tibial guide of sagittal alignment of PCL-substituting total knee arthroplasty.

    Science.gov (United States)

    Han, Hyuk-Soo; Kang, Seung-Baik; Jo, Chris H; Kim, Sun-Hong; Lee, Jung-Ha

    2010-10-01

    Experimental and clinical studies on the accuracy of the intramedullary alignment method have produced different results, and few have addressed accuracy in the sagittal plane. Reported deviations are not only attributable to the alignment method but also to radiological errors. The purpose of this study was to evaluate the accuracy of the intramedullary alignment method in the sagittal plane using computed tomography (CT) and 3-dimensional imaging software. Thirty-one TKAs were performed using an intramedullary alignment method involving the insertion of a long 8-mm diameter rod into the medullary canal to the distal metaphysis of the tibia. All alignment instruments were set to achieve an ideal varus/valgus angle of 0° in the coronal plane and a tibial slope of 0° in the sagittal plane. The accuracy of the intramedullary alignment system was assessed by measuring the coronal tibial component angle and sagittal tibial slope angles, i.e., angles between the tibial anatomical axis and the tangent to the medial and lateral tibial plateau or the cut-surface. The mean coronal tibial component angle was 88.5° ± 1.2° and the mean tibial component slope in the sagittal plane was 1.6° ± 1.2° without anterior slope. Our intramedullary tibial alignment method, which involves passing an 8-mm diameter long rod through the tibial shaft isthmus, showed good accuracy (less than 3 degrees of variation and no anterior slope) in the sagittal plane in neutral or varus knees.

  2. Axial myopathy

    DEFF Research Database (Denmark)

    Witting, Nanna; Andersen, Linda K; Vissing, John

    2016-01-01

    Classically, myopathies are categorized according to limb or cranial nerve muscle affection, but with the growing use of magnetic resonance imaging it has become evident that many well-known myopathies have significant involvement of the axial musculature. New disease entities with selective axial...

  3. Axial spondyloarthritis.

    Science.gov (United States)

    Sieper, Joachim; Braun, Jürgen; Dougados, Maxime; Baeten, Dominique

    2015-07-09

    The term axial spondyloarthritis covers both non-radiographic disease and radiographic disease (also known as ankylosing spondylitis). Some studies have been performed to investigate the prevalence of axial spondyloarthritis, although most are limited to patients with radiographic disease. A strong genetic association has been shown between axial spondyloarthritis and human leukocyte antigen-B27 (HLA-B27), but the pathogenetic role of HLA-B27 has not yet been clarified. Tumour necrosis factor (TNF), IL-17, IL-23 and downstream pathways also seem to be important - based on the good results of therapies directed against these molecules - but their exact role in the inflammatory process is also not yet clear. Elucidating the interaction between osteoproliferation and inflammation will be crucial for the prevention of long-term structural damage of the bone. The development of new criteria for classification, diagnosis and screening of patients with axial spondyloarthritis will enable earlier intervention for this chronic inflammatory disease. MRI has become an important tool for the early detection of axial spondyloarthritis. NSAIDs and TNF blockers are effective therapies, including in the early non-radiographic stage. Therapeutic blockade of IL-17 or IL-23 seems to be a promising new treatment option. Tools for measuring quality of life in axial spondyloarthritis have become relevant to assess the impact that the disease has on patients. These diagnostic and therapeutic advances will continue to change the management of axial spondyloarthritis, and new insights into the disease pathogenesis will hopefully accelerate this process. For an illustrated summary of this Primer, visit: http://go.nature.com/51b1af.

  4. Measurement and Finite Element Model Validation of Immature Porcine Brain-Skull Displacement during Rapid Sagittal Head Rotations.

    Science.gov (United States)

    Pasquesi, Stephanie A; Margulies, Susan S

    2018-01-01

    Computational models are valuable tools for studying tissue-level mechanisms of traumatic brain injury, but to produce more accurate estimates of tissue deformation, these models must be validated against experimental data. In this study, we present in situ measurements of brain-skull displacement in the neonatal piglet head ( n  = 3) at the sagittal midline during six rapid non-impact rotations (two rotations per specimen) with peak angular velocities averaging 51.7 ± 1.4 rad/s. Marks on the sagittally cut brain and skull/rigid potting surfaces were tracked, and peak values of relative brain-skull displacement were extracted and found to be significantly less than values extracted from a previous axial plane model. In a finite element model of the sagittally transected neonatal porcine head, the brain-skull boundary condition was matched to the measured physical experiment data. Despite smaller sagittal plane displacements at the brain-skull boundary, the corresponding finite element boundary condition optimized for sagittal plane rotations is far less stiff than its axial counterpart, likely due to the prominent role of the boundary geometry in restricting interface movement. Finally, bridging veins were included in the finite element model. Varying the bridging vein mechanical behavior over a previously reported range had no influence on the brain-skull boundary displacements. This direction-specific sagittal plane boundary condition can be employed in finite element models of rapid sagittal head rotations.

  5. Measurement and Finite Element Model Validation of Immature Porcine Brain–Skull Displacement during Rapid Sagittal Head Rotations

    Directory of Open Access Journals (Sweden)

    Stephanie A. Pasquesi

    2018-02-01

    Full Text Available Computational models are valuable tools for studying tissue-level mechanisms of traumatic brain injury, but to produce more accurate estimates of tissue deformation, these models must be validated against experimental data. In this study, we present in situ measurements of brain–skull displacement in the neonatal piglet head (n = 3 at the sagittal midline during six rapid non-impact rotations (two rotations per specimen with peak angular velocities averaging 51.7 ± 1.4 rad/s. Marks on the sagittally cut brain and skull/rigid potting surfaces were tracked, and peak values of relative brain–skull displacement were extracted and found to be significantly less than values extracted from a previous axial plane model. In a finite element model of the sagittally transected neonatal porcine head, the brain–skull boundary condition was matched to the measured physical experiment data. Despite smaller sagittal plane displacements at the brain–skull boundary, the corresponding finite element boundary condition optimized for sagittal plane rotations is far less stiff than its axial counterpart, likely due to the prominent role of the boundary geometry in restricting interface movement. Finally, bridging veins were included in the finite element model. Varying the bridging vein mechanical behavior over a previously reported range had no influence on the brain–skull boundary displacements. This direction-specific sagittal plane boundary condition can be employed in finite element models of rapid sagittal head rotations.

  6. Nonlinear magnetohydrodynamics of footpoint-driven coronal loops

    NARCIS (Netherlands)

    Poedts, S.; Boynton, G. C.

    1996-01-01

    Results are presented from magnetohydrodynamic (MHD) simulations of the phase-mixing and resonant absorption of standing torsional Alfven waves generated by motion at the footpoint of a line-tied coronal loop with axial symmetry. The high wave amplitudes that develop in the resonant layer cause

  7. Coronal Waves and Oscillations

    Directory of Open Access Journals (Sweden)

    Nakariakov Valery M.

    2005-07-01

    Full Text Available Wave and oscillatory activity of the solar corona is confidently observed with modern imaging and spectral instruments in the visible light, EUV, X-ray and radio bands, and interpreted in terms of magnetohydrodynamic (MHD wave theory. The review reflects the current trends in the observational study of coronal waves and oscillations (standing kink, sausage and longitudinal modes, propagating slow waves and fast wave trains, the search for torsional waves, theoretical modelling of interaction of MHD waves with plasma structures, and implementation of the theoretical results for the mode identification. Also the use of MHD waves for remote diagnostics of coronal plasma - MHD coronal seismology - is discussed and the applicability of this method for the estimation of coronal magnetic field, transport coefficients, fine structuring and heating function is demonstrated.

  8. Coronal 2D MR cholangiography overestimates the length of the right hepatic duct in liver transplantation donors

    International Nuclear Information System (INIS)

    Kim, Bohyun; Kim, Kyoung Won; Kim, So Yeon; Park, So Hyun; Lee, Jeongjin; Song, Gi Won; Jung, Dong-Hwan; Ha, Tae-Yong; Lee, Sung Gyu

    2017-01-01

    To compare the length of the right hepatic duct (RHD) measured on rotatory coronal 2D MR cholangiography (MRC), rotatory axial 2D MRC, and reconstructed 3D MRC. Sixty-seven donors underwent coronal and axial 2D projection MRC and 3D MRC. RHD length was measured and categorized as ultrashort (≤1 mm), short (>1-14 mm), and long (>14 mm). The measured length, frequency of overestimation, and the degree of underestimation between two 2D MRC sets were compared to 3D MRC. The length of the RHD from 3D MRC, coronal 2D MRC, and axial 2D MRC showed significant difference (p < 0.05). RHD was frequently overestimated on the coronal than on axial 2D MRC (61.2 % vs. 9 %; p <.0001). On coronal 2D MRC, four (6 %) with short RHD and one (1.5 %) with ultrashort RHD were over-categorized as long RHD. On axial 2D MRC, overestimation was mostly <1 mm (83.3 %), none exceeding 3 mm or over-categorized. The degree of underestimation between the two projection planes was comparable. Coronal 2D MRC overestimates the RHD in liver donors. We suggest adding axial 2D MRC to conventional coronal 2D MRC in the preoperative workup protocol for living liver donors to avoid unexpected confrontation with multiple ductal openings when harvesting the graft. (orig.)

  9. Coronal 2D MR cholangiography overestimates the length of the right hepatic duct in liver transplantation donors

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bohyun [University of Ulsan College of Medicine, Department of Radiology, Asan Medical Center, 88, Olympic-ro 43-gil, Songpa-gu, Seoul (Korea, Republic of); Ajou University School of Medicine, Department of Radiology, Ajou University Medical Center, Suwon (Korea, Republic of); Kim, Kyoung Won; Kim, So Yeon; Park, So Hyun [University of Ulsan College of Medicine, Department of Radiology, Asan Medical Center, 88, Olympic-ro 43-gil, Songpa-gu, Seoul (Korea, Republic of); Lee, Jeongjin [Soongsil University, School of Computer Science and Engineering, Seoul (Korea, Republic of); Song, Gi Won; Jung, Dong-Hwan; Ha, Tae-Yong; Lee, Sung Gyu [University of Ulsan College of Medicine, Department of Surgery, Division of Hepatobiliary and Liver Transplantation Surgery, Asan Medical Center, Seoul (Korea, Republic of)

    2017-05-15

    To compare the length of the right hepatic duct (RHD) measured on rotatory coronal 2D MR cholangiography (MRC), rotatory axial 2D MRC, and reconstructed 3D MRC. Sixty-seven donors underwent coronal and axial 2D projection MRC and 3D MRC. RHD length was measured and categorized as ultrashort (≤1 mm), short (>1-14 mm), and long (>14 mm). The measured length, frequency of overestimation, and the degree of underestimation between two 2D MRC sets were compared to 3D MRC. The length of the RHD from 3D MRC, coronal 2D MRC, and axial 2D MRC showed significant difference (p < 0.05). RHD was frequently overestimated on the coronal than on axial 2D MRC (61.2 % vs. 9 %; p <.0001). On coronal 2D MRC, four (6 %) with short RHD and one (1.5 %) with ultrashort RHD were over-categorized as long RHD. On axial 2D MRC, overestimation was mostly <1 mm (83.3 %), none exceeding 3 mm or over-categorized. The degree of underestimation between the two projection planes was comparable. Coronal 2D MRC overestimates the RHD in liver donors. We suggest adding axial 2D MRC to conventional coronal 2D MRC in the preoperative workup protocol for living liver donors to avoid unexpected confrontation with multiple ductal openings when harvesting the graft. (orig.)

  10. Sagittal reconstruction computed tomography in metrizamide cisternography. Useful diagnostic procedure for malformations in craniovertebral junction and posterior fossa

    Energy Technology Data Exchange (ETDEWEB)

    Mochizuki, H.; Okita, N.; Fujii, T.; Yoshioka, M.; Saito, H. (Tohoku Univ., Sendai (Japan). School of Medicine)

    1982-08-01

    We studied the sagittal reconstruction technique in computed tomography with metrizamide. Ten ml of metrizamide, 170 mg iodine/ml in concentration, were injected by lumbar puncture. After diffusion of the injected metrizamide, axial computed tomograms were taken by thin slice width (5 mm) with overlapped technique. Then electrical sagittal reconstruction was carried out by optioned software. Injection of metrizamide, non-ionic water soluble contrast media, made clear contrasts among bone, brain parenchyma and cerebrospinal fluid with computed tomography. Sagittal reconstruction technique could reveal more precise details and accurate anatomical relations than ordinary axial computed tomography. This technique was applied on 3 cases (Arnold-Chiari malformation, large cisterna magna and partial agenesis cerebellar vermis), which demonstrated a useful diagnostic procedure for abnormalities of craniovertebral junction and posterior fossa. The adverse reactions of metrizamide were negligible in our series.

  11. Biomechanical comparison of sagittal-parallel versus non-parallel pedicle screw placement.

    Science.gov (United States)

    Farshad, Mazda; Farshad-Amacker, Nadja A; Bachmann, Elias; Snedeker, Jess G; Schmid, Samuel L

    2014-11-01

    While convergent placement of pedicle screws in the axial plane is known to be more advantageous biomechanically, surgeons intuitively aim toward a parallel placement of screws in the sagittal plane. It is however not clear whether parallel placement of screws in the sagittal plane is biomechanically superior to a non-parallel construct. The hypothesis of this study is that sagittal non-parallel pedicle screws do not have an inferior initial pull-out strength compared to parallel placed screws. The established lumbar calf spine model was used for determination of pull-out strength in parallel and non-parallel intersegmental pedicle screw constructs. Each of six lumbar calf spines (L1-L6) was divided into three levels: L1/L2, L3/L4 and L5/L6. Each segment was randomly instrumented with pedicle screws (6/45 mm) with either the standard technique of sagittal parallel or non-parallel screw placement, respectively, under fluoroscopic control. CT was used to verify the intrapedicular positioning of all screws. The maximum pull-out forces and type of failure were registered and compared between the groups. The pull-out forces were 5,394 N (range 4,221 N to 8,342 N) for the sagittal non-parallel screws and 5,263 N (range 3,589 N to 7,554 N) for the sagittal-parallel screws (p = 0.838). Interlevel comparisons also showed no statistically significant differences between the groups with no relevant difference in failure mode. Non-parallel pedicle screws in the sagittal plane have at least equal initial fixation strength compared to parallel pedicle screws in the setting of the here performed cadaveric calf spine experiments.

  12. Pedicle subtraction osteotomies (PSO) in the lumbar spine for sagittal deformities.

    Science.gov (United States)

    Berjano, Pedro; Aebi, Max

    2015-01-01

    The narrow correlation between sagittal alignment parameters and clinical outcomes has been widely established, demonstrating that improper sagittal alignment is a clinical condition that is associated with increased pain and limitations in patients' functional ability. Lumbar pedicle subtraction osteotomy (PSO) is indicated in the treatment of large sagittal (more than 25° of rigid loss of lordosis) deformities of the lumbar spine or its combination with coronal deformity, especially when they are rigid. Indication should be based on careful assessment of the severity of symptoms, functional impairment, functional expectations of the patient, general clinical condition and surgical and anesthesiological team experience. Risk should be carefully assessed and discussed to obtain appropriate informed consent. Surgical planning includes selection of the safest levels for the upper and lower instrumented vertebra, site of the osteotomy, modality of fixation, and, most importantly angular value of the correction goal (target lumbar lordosis). Failure to adequately obtain the necessary amount of sagittal correction is the most frequent cause of failure and reoperation. PSO is a valuable surgical procedure in correction of severe hypolordosis (=relative kyphosis) in the lumbar spine. It is a demanding procedure for the surgeon, the anesthesiologist and the intensive care team. Although its complication rate is high, it has a substantial positive impact in the quality of life of patients, including the elderly.

  13. The value of coronal image reconstructions of HRCT using MDCT for the assessment of bronchiectasis: experiment with 64 MDCTs

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Soo Jin; Kim, Hyung Sik; Jeong, Sung Hwan; Jin, Wook; Yang, Dal Mo [Gachon University of Medicine and Science, Incheon (Korea, Republic of)

    2006-09-15

    The aim of our study was to evaluate the value of coronal image reconstructions of HRCT with using 64 MDCT scans for the assessment of bronchiectasis. Chest CT scans (0.6-mm collimation, table speed of 14 mm/sec and a rotation time of 0.5 sec) that employed 64 MDCT images (Somatom Sensation 64, Siemens) without contrast media were performed in 56 patients (21 males and 35 females, mean age: 55 years) who displayed hemoptysis. The images were reconstructed with a 1 mm slice thickness in the axial (10 mm apart) and coronal (10 mm apart) planes with using a high frequency algorithm, and they were sent to PACS monitors. The axial images were assessed with and without the coronal images by two radiologists at two separate occasions. The presence of bronchiectasis was decided upon by consensus diagnosis of the two radiologists. The detection rates of bronchiectasis were compared between the readings with using the axial images alone and the readings with using both the axial and coronal images. The detection rate of bronchiectasis was significantly higher with using both the axial and coronal images than with using with axial images alone (82.1%, 46/56 patients Vs 64.3%, 36/56 patients, respectively, {rho} = 0.001). The detection rates for all the lobes, except for the superior division of the left upper lobe, were significantly improved with using both the axial and coronal images (RUL; {rho} = 0.013, RML; {rho} = 0.002, RLL; 0.024, Lt lingular segment; {rho} = 0.004, LLL; {rho} = 0.018). The coronal images of HRCT with using 64 MDCT improved the detection rate of bronchiectasis in the patients with hemoptysis when they were used in conjunction with the standard axial images. We suggest that HRCT with the coronal images should be obtained for the patients with hemoptysis, despite that the simple chest radiographs are often normal or they have non-specific findings.

  14. Mechanisms of Coronal Heating

    Indian Academy of Sciences (India)

    The Sun is a mysterious star. The high temperature of the chromosphere and corona present one of the most puzzling problems of solar physics. Observations show that the solar coronal heating problem is highly complex with many different facts. It is likely that different heating mechanisms are at work in solar corona.

  15. Coronal mass ejections and coronal structures

    Science.gov (United States)

    Hildner, E.; Bassi, J.; Bougeret, J. L.; Duncan, R. A.; Gary, D. E.; Gergely, T. E.; Harrison, R. A.; Howard, R. A.; Illing, R. M. E.; Jackson, B. V.

    1986-01-01

    Research on coronal mass ejections (CMF) took a variety of forms, both observational and theoretical. On the observational side there were: case studies of individual events, in which it was attempted to provide the most complete descriptions possible, using correlative observations in diverse wavelengths; statistical studies of the properties CMEs and their associated activity; observations which may tell us about the initiation of mass ejections; interplanetary observations of associated shocks and energetic particles even observations of CMEs traversing interplanetary space; and the beautiful synoptic charts which show to what degree mass ejections affect the background corona and how rapidly (if at all) the corona recovers its pre-disturbance form. These efforts are described in capsule form with an emphasis on presenting pictures, graphs, and tables so that the reader can form a personal appreciation of the work and its results.

  16. Analysis of sagittal spinopelvic parameters in achondroplasia.

    Science.gov (United States)

    Hong, Jae-Young; Suh, Seung-Woo; Modi, Hitesh N; Park, Jong-Woong; Park, Jung-Ho

    2011-08-15

    Prospective radiological analysis of patients with achondroplasia. To analyze sagittal spinal alignment and pelvic orientation in achondroplasia patients. Knowledge of sagittal spinopelvic parameters is important for the treatment of achondroplasia, because they differ from those of the normal population and can induce pain. The study and control groups were composed of 32 achondroplasia patients and 24 healthy volunteers, respectively. All underwent lateral radiography of the whole spine including hip joints. The radiographic parameters examined were sacral slope (SS), pelvic tilt, pelvic incidence (PI), S1 overhang, thoracic kyphosis, T10-L2 kyphosis, lumbar lordosis (LL1, LL2), and sagittal balance. Statistical analysis was performed to identify significant differences between the two groups. In addition, correlations between parameters and symptoms were sought. Sagittal spinopelvic parameters, namely, pelvic tilt, pelvic incidence, S1 overhang, thoracic kyphosis, T10-L2 kyphosis, lumbar lordosis 1 and sagittal balance were found to be significantly different in the patient and control groups (P achondroplasia patients and normal healthy controls. The present study shows that sagittal spinal and pelvic parameters can assist the treatment of spinal disorders in achondroplasia patients.

  17. Contribution of thin slice (1 mm) oblique coronal proton density-weighted MR images for assessment of anteromedial and posterolateral bundle damage in anterior cruciate ligament injuries

    Energy Technology Data Exchange (ETDEWEB)

    Gokalp, Gokhan, E-mail: drgokhangokalp@yahoo.com [Department of Radiology, Uludag University Medical Faculty, Gorukle, Bursa (Turkey); Demirag, Burak, E-mail: bdemirag@uludag.edu.tr [Department of Orthopedy, Uludag University Medical Faculty, Gorukle, Bursa (Turkey); Nas, Omer Fatih, E-mail: omerfatihnas@gmail.com [Department of Radiology, Uludag University Medical Faculty, Gorukle, Bursa (Turkey); Aydemir, Mehmet Fatih, E-mail: fatiha@yahoo.com [Department of Orthopedy, Uludag University Medical Faculty, Gorukle, Bursa (Turkey); Yazici, Zeynep, E-mail: zyazici@uludag.edu.tr [Department of Radiology, Uludag University Medical Faculty, Gorukle, Bursa (Turkey)

    2012-09-15

    Purpose: To evaluate the diagnostic efficacy of using additional oblique coronal 1 mm proton density-weighted (PDW) MR imaging of the knee for detection and grading anterior cruciate ligament (ACL), anteromedial bundle (AMB) and posterolateral bundle (PLB) injuries. Materials and methods: We prospectively assessed preoperative MR images of 50 patients (36 men, 14 women; age range, 18–62 years). First, we compared the diagnostic performance of routine sagittal (3 mm) and additional oblique coronal images (1 mm) for ACL tears. Then, we compared the tear types (AMB or PLB) and grade presumed from oblique coronal MR imaging with arthroscopy. Results: Arthroscopy revealed ACL tear in 24 (48%) patients. There was significant difference between sagittal images and arthroscopy results for ACL tear recognition (p < 0.001). No significant difference was detected for oblique coronal images when compared with arthroscopy results (p = 0.180). Sensitivity and specificity values for ACL tear diagnosis were 37.04% and 95.65% for sagittal images; 74.07% and 91.30% for oblique coronal images. There was no significant difference between arthroscopy and oblique coronal MR images in grading AMB and PLB injuries (p > 0.05). Conclusion: Addition of thin slice oblique coronal images to conventional sequences could better contribute to better verifying the presence of ACL tear and in determining its grade.

  18. Coronal Mass Ejections

    CERN Document Server

    Kunow, H; Linker, J. A; Schwenn, R; Steiger, R

    2006-01-01

    It is well known that the Sun gravitationally controls the orbits of planets and minor bodies. Much less known, however, is the domain of plasma fields and charged particles in which the Sun governs a heliosphere out to a distance of about 15 billion kilometers. What forces activates the Sun to maintain this power? Coronal Mass Ejections (CMEs) and their descendants are the troops serving the Sun during high solar activity periods. This volume offers a comprehensive and integrated overview of our present knowledge and understanding of Coronal Mass Ejections (CMEs) and their descendants, Interplanetary CMEs (ICMEs). It results from a series of workshops held between 2000 and 2004. An international team of about sixty experimenters involved e.g. in the SOHO, ULYSSES, VOYAGER, PIONEER, HELIOS, WIND, IMP, and ACE missions, ground observers, and theoreticians worked jointly on interpreting the observations and developing new models for CME initiations, development, and interplanetary propagation. The book provides...

  19. Significance of sagittal reformations in routine thoracic and abdominal multislice CT studies for detecting osteoporotic fractures and other spine abnormalities

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, Dirk; Bauer, Jan S.; Zeile, Martin; Rummeny, Ernst J. [Klinikum Rechts der Isar, TU Muenchen, Department of Radiology, Muenchen (Germany); Link, Thomas M. [Musculoskeletal and Quantitative Imaging Research, UCSF, Department of Radiology, San Francisco, CA (United States)

    2008-08-15

    The purpose was to assess osteoporotic vertebral fractures and other spinal lesions in sagittal reformations obtained from routine multidetector computed tomography (MDCT) studies of the thorax and abdomen, to compare sagittal reformations with axial images in detecting these lesions and to investigate how frequently they were missed in the official radiology report. Routine abdominal or thoracoabdominal MDCT using a standard protocol was performed in 112 postmenopausal women. Axial images and sagittal reformations were analyzed separately by two radiologists in consensus and were compared in order to evaluate how often spinal lesions could be detected. In addition the official radiology reports were assessed to determine how many of those abnormalities were identified. Spine abnormalities were visualized in 101/112 postmenopausal women. In 27 patients osteoporotic vertebral deformities were found; 6 of these were shown in the axial images, but none of these were diagnosed in the official radiology report. Additional abnormalities included degenerative disc disease, osteoarthritis of the facet joints, scoliosis, hemangiomas and bone metastases. In only 9/101 patients spine abnormalities were mentioned in the radiology report. Sagittal reformations of standard MDCT images provide important additional information on spinal abnormalities; in particular, osteoporotic vertebral deformities are substantially better detected. (orig.)

  20. Impulsively Generated Wave Trains in Coronal Structures. II. Effects of Transverse Structuring on Sausage Waves in Pressurelesss Slabs

    Science.gov (United States)

    Li, Bo; Guo, Ming-Zhe; Yu, Hui; Chen, Shao-Xia

    2018-03-01

    Impulsively generated sausage wave trains in coronal structures are important for interpreting a substantial number of observations of quasi-periodic signals with quasi-periods of order seconds. We have previously shown that the Morlet spectra of these wave trains in coronal tubes depend crucially on the dispersive properties of trapped sausage waves, the existence of cutoff axial wavenumbers, and the monotonicity of the dependence of the axial group speed on the axial wavenumber in particular. This study examines the difference a slab geometry may introduce, for which purpose we conduct a comprehensive eigenmode analysis, both analytically and numerically, on trapped sausage modes in coronal slabs with a considerable number of density profiles. For the profile descriptions examined, coronal slabs can trap sausage waves with longer axial wavelengths, and the group speed approaches the internal Alfvén speed more rapidly at large wavenumbers in the cylindrical case. However, common to both geometries, cutoff wavenumbers exist only when the density profile falls sufficiently rapidly at distances far from coronal structures. Likewise, the monotonicity of the group speed curves depends critically on the profile steepness right at the structure axis. Furthermore, the Morlet spectra of the wave trains are shaped by the group speed curves for coronal slabs and tubes alike. Consequently, we conclude that these spectra have the potential for inferring the subresolution density structuring inside coronal structures, although their detection requires an instrumental cadence of better than ∼1 s.

  1. Investigation of reconstruction conditions in sagittal-plane multiplanar reconstruction of the temporal bone

    International Nuclear Information System (INIS)

    Suzuki, Miyako; Yoshikawa, Hiroshi; Hosokawa, Akira; Ichikawa, Ginichiro; Kobayashi, Kenichi; Ando, Ichiro

    2002-01-01

    In recent years, it has become possible to quickly obtain a large amount of 3D data with high continuity by helical CT scanning, in which the body is scanned continuously in a helical fashion. MPR (multiplanar reconstruction) can be performed using this data to generate images in arbitrary sectional planes, making it possible to obtain sagittal-plane images of the highest quality, which is useful for surgical planning. However, the procedures involved are rather complicated. Therefore, this study was conducted to investigate conditions for standardization of sagittal-plane MPR examinations performed using Xvigor CT scanners and Xtension. The results showed that a slice interval of 1 mm, no imaging filter, a zooming factor of 1.5, a window level of 350, and a window width of 3500 are the optimal imaging conditions. The stapes can be visualized in 70% of cases with sagittal-plane MPR based on axial images, and can be recognized at surgery in 75% or more of cases. Images of consistent quality can be obtained by standardizing the conditions for sagittal-plane MPR, which should prove advantageous in the clinical setting. (author)

  2. Finite element analysis of sagittal balance in different morphotype: Forces and resulting strain in pelvis and spine.

    Science.gov (United States)

    Filardi, Vincenzo; Simona, Portaro; Cacciola, Giorgio; Bertino, Salvatore; Soliera, Luigi; Barbanera, Andrea; Pisani, Alessandro; Milardi, Demetrio; Alessia, Bramanti

    2017-06-01

    In humans, vertical posture acquisition caused several changes in bones and muscles which can be assumed as verticalization. Pelvis, femur, and vertebral column gain an extension position which decreases muscular work by paravertebral muscles in the latter. It's widely known that six different morphological categories exist; each category differs from the others by pelvic parameters and vertebral column curvatures. Both values depend on the Pelvic Incidence, calculated as the angle between the axes passing through the rotation centre of the two femur heads and the vertical axis passing through the superior plate of the sacrum. The aim of this study is to evaluate the distribution of stress and the resulting strain along the axial skeleton using finite element analysis. The use of this computational method allows performing different analyses investigating how different bony geometries and skeletal structures can behavior under specific loading conditions. A computerized tomography (CT) of artificial bones, carried on at 1.5 mm of distance along sagittal, coronal and axial planes with the knee at 0° flexion (accuracy 0.5 mm), was used to obtain geometrical data of the model developed. Lines were imported into a commercial code (Hypermesh by Altair ® ) in order to interpolate main surfaces and create the solid version of the model. In particular six different models were created according Roussoly's classification, by arranging geometrical position of the skeletal components. Loading conditions were obtained by applying muscular forces components to T1 till to L5, according to a reference model (Daniel M. 2011), and a fixed constrain was imposed on the lower part of the femurs. Materials were assumed as elastic with an Elastic modulus of 15 GPa, a Shear Modulus of 7 GPa for bony parts, and an Elastic modulus of 6 MPa, a Shear Modulus of 3 MPa for cartilaginous parts. Six different simulations have been carried out in order to evaluate the mechanical behavior

  3. Coronal Magnetic Field Models

    Science.gov (United States)

    Wiegelmann, Thomas; Petrie, Gordon J. D.; Riley, Pete

    2017-09-01

    Coronal magnetic field models use photospheric field measurements as boundary condition to model the solar corona. We review in this paper the most common model assumptions, starting from MHD-models, magnetohydrostatics, force-free and finally potential field models. Each model in this list is somewhat less complex than the previous one and makes more restrictive assumptions by neglecting physical effects. The magnetohydrostatic approach neglects time-dependent phenomena and plasma flows, the force-free approach neglects additionally the gradient of the plasma pressure and the gravity force. This leads to the assumption of a vanishing Lorentz force and electric currents are parallel (or anti-parallel) to the magnetic field lines. Finally, the potential field approach neglects also these currents. We outline the main assumptions, benefits and limitations of these models both from a theoretical (how realistic are the models?) and a practical viewpoint (which computer resources to we need?). Finally we address the important problem of noisy and inconsistent photospheric boundary conditions and the possibility of using chromospheric and coronal observations to improve the models.

  4. Light axial vector mesons

    Science.gov (United States)

    Chen, Kan; Pang, Cheng-Qun; Liu, Xiang; Matsuki, Takayuki

    2015-04-01

    Inspired by the abundant experimental observation of axial-vector states, we study whether the observed axial-vector states can be categorized into the conventional axial-vector meson family. In this paper we carry out an analysis based on the mass spectra and two-body Okubo-Zweig-Iizuka-allowed decays. Besides testing the possible axial-vector meson assignments, we also predict abundant information for their decays and the properties of some missing axial-vector mesons, which are valuable for further experimental exploration of the observed and predicted axial-vector mesons.

  5. Coronal Mass Ejections: Observations

    Directory of Open Access Journals (Sweden)

    David F. Webb

    2012-06-01

    Full Text Available Solar eruptive phenomena embrace a variety of eruptions, including flares, solar energetic particles, and radio bursts. Since the vast majority of these are associated with the eruption, development, and evolution of coronal mass ejections (CMEs, we focus on CME observations in this review. CMEs are a key aspect of coronal and interplanetary dynamics. They inject large quantities of mass and magnetic flux into the heliosphere, causing major transient disturbances. CMEs can drive interplanetary shocks, a key source of solar energetic particles and are known to be the major contributor to severe space weather at the Earth. Studies over the past decade using the data sets from (among others the SOHO, TRACE, Wind, ACE, STEREO, and SDO spacecraft, along with ground-based instruments, have improved our knowledge of the origins and development of CMEs at the Sun and how they contribute to space weather at Earth. SOHO, launched in 1995, has provided us with almost continuous coverage of the solar corona over more than a complete solar cycle, and the heliospheric imagers SMEI (2003 – 2011 and the HIs (operating since early 2007 have provided us with the capability to image and track CMEs continually across the inner heliosphere. We review some key coronal properties of CMEs, their source regions and their propagation through the solar wind. The LASCO coronagraphs routinely observe CMEs launched along the Sun-Earth line as halo-like brightenings. STEREO also permits observing Earth-directed CMEs from three different viewpoints of increasing azimuthal separation, thereby enabling the estimation of their three-dimensional properties. These are important not only for space weather prediction purposes, but also for understanding the development and internal structure of CMEs since we view their source regions on the solar disk and can measure their in-situ characteristics along their axes. Included in our discussion of the recent developments in CME

  6. An overview of coronal seismology.

    Science.gov (United States)

    De Moortel, I

    2005-12-15

    The idea of exploiting observed oscillations as a diagnostic tool for determining the physical conditions of the coronal plasma was first suggested several decades ago (Roberts et al. 1984 Astrophys. J. 279, 857). Until recently, the application of this idea has been very limited by a lack of high-quality observations of coronal oscillations. However, during the last few years, this situation has changed dramatically, especially due to space-based observations by the Solar and Heliospheric Observatory and the Transition Region and Coronal Explorer and waves and oscillations have now been observed in a wide variety of solar structures, such as coronal loops, polar plumes and prominences. This paper will briefly summarize MHD wave theory, which forms the basis for coronal seismology, as well as present an overview of the variety of recently observed waves and oscillations in the solar corona. The present state of coronal seismology will also be discussed. Currently, the uncertainty associated with the obtained parameters is still considerable and, hence, the results require a cautious interpretation. However, these examples do show that coronal seismology is rapidly being transformed from a theoretical possibility to a viable technique.

  7. Morphological segmentation for sagittal plane image analysis.

    Science.gov (United States)

    Bezerra, F N; Paula, I C; Medeiros, F S; Ushizima, D M; Cintra, L S

    2010-01-01

    This paper introduces a morphological image segmentation method by applying watershed transform with markers to scale-space smoothed images and furthermore provides images for clinical monitoring and analysis of patients. The database comprises sagittal plane images taken from a digital camera of patients submitted to Global Postural Reeducation (GPR) physiotherapy treatment. Orthopaedic specialists can use these segmented images to diagnose posture problems, assess physiotherapy treatment evolution and thus reduce diagnostic errors due to subjective analysis.

  8. Ellis-van Creveld Syndrome with Sagittal Craniosynostosis.

    Science.gov (United States)

    Fischer, Andrew S; Weathers, William M; Wolfswinkel, Erik M; Bollo, Robert J; Hollier, Larry H; Buchanan, Edward P

    2015-06-01

    Ellis-van Creveld syndrome (EVC) is a rare disorder (the incidence is estimated at around 7/1,000,000) characterized by the clinical tetrad of chondrodystrophy, polydactyly, ectodermal dysplasia, and cardiac anomalies. Sagittal synostosis is characterized by a dolichocephalic head shape resulting from premature fusion of the sagittal suture. Both are rare disorders, which have never been reported together. We present a case of EVC and sagittal synostosis. We report the clinical features of a Hispanic boy with EVC and sagittal craniosynostosis who underwent cranial vault remodeling. The presentation of this patient is gone over in detail. A never before reported case of EVC and sagittal synostosis is presented in detail.

  9. Coronal reconstruction of unenhanced abdominal CT for correct ureteral stone size classification

    International Nuclear Information System (INIS)

    Berkovitz, Nadav; Simanovsky, Natalia; Hiller, Nurith; Katz, Ran; Salama, Shaden

    2010-01-01

    To determine whether size measurement of a urinary calculus in coronal reconstruction of computed tomography (CT) differs from stone size measured in the axial plane, and whether the difference alters clinical decision making. We retrospectively reviewed unenhanced CT examinations of 150 patients admitted to the emergency room (ER) with acute renal colic. Maximal ureteral calculus size was measured on axial slices and coronal reconstructions. Clinical significance was defined as an upgrading or downgrading of stone size according to accepted thresholds of treatment: ≤5 mm, 6-9 mm and ≥10 mm. There were 151 stones in 150 patients (male:female 115:34, mean age 41 years). Transverse stone diameters ranged from 1 to 11 mm (mean 4 mm). On coronal images, 56 (37%) stones were upgraded in severity; 46 (30%) from below 5 mm to 6 mm or more, and ten (7%) from 6-9 mm to 10 mm or more. Transverse measurement on the axial slices enabled correct categorization of 95 stones (63%). Transverse calculus measurement on axial slices often underestimates stone size and provides incorrect clinical classification of the true maximal stone diameter. Coronal reconstruction provides additional information in patients with renal colic that may alter treatment strategy. (orig.)

  10. Coronal reconstruction of unenhanced abdominal CT for correct ureteral stone size classification

    Energy Technology Data Exchange (ETDEWEB)

    Berkovitz, Nadav; Simanovsky, Natalia; Hiller, Nurith [Hadassah Mount Scopus - Hebrew University Medical Center, Department of Radiology, Jerusalem (Israel); Katz, Ran [Hadassah Mount Scopus - Hebrew University Medical Center, Department of Urology, Jerusalem (Israel); Salama, Shaden [Hadassah Mount Scopus - Hebrew University Medical Center, Department of Emergency Medicine, Jerusalem (Israel)

    2010-05-15

    To determine whether size measurement of a urinary calculus in coronal reconstruction of computed tomography (CT) differs from stone size measured in the axial plane, and whether the difference alters clinical decision making. We retrospectively reviewed unenhanced CT examinations of 150 patients admitted to the emergency room (ER) with acute renal colic. Maximal ureteral calculus size was measured on axial slices and coronal reconstructions. Clinical significance was defined as an upgrading or downgrading of stone size according to accepted thresholds of treatment: {<=}5 mm, 6-9 mm and {>=}10 mm. There were 151 stones in 150 patients (male:female 115:34, mean age 41 years). Transverse stone diameters ranged from 1 to 11 mm (mean 4 mm). On coronal images, 56 (37%) stones were upgraded in severity; 46 (30%) from below 5 mm to 6 mm or more, and ten (7%) from 6-9 mm to 10 mm or more. Transverse measurement on the axial slices enabled correct categorization of 95 stones (63%). Transverse calculus measurement on axial slices often underestimates stone size and provides incorrect clinical classification of the true maximal stone diameter. Coronal reconstruction provides additional information in patients with renal colic that may alter treatment strategy. (orig.)

  11. Dynamical behaviour in coronal loops

    Science.gov (United States)

    Haisch, Bernhard M.

    1986-01-01

    Rapid variability has been found in two active region coronal loops observed by the X-ray Polychromator (XRP) and the Hard X-ray Imaging Spectrometer (HXIS) onboard the Solar Maximum Mission (SMM). There appear to be surprisingly few observations of the short-time scale behavior of hot loops, and the evidence presented herein lends support to the hypothesis that coronal heating may be impulsive and driven by flaring.

  12. Heating solar coronal holes

    Science.gov (United States)

    Parker, E. N.

    1991-01-01

    It has been shown that the coronal hole, and the associated high-speed stream in the solar wind, are powered by a heat input of the order of 500,000 ergs/sq cm s, with most of the heat injected in the first 1-2 solar radii, and perhaps 100,000 ergs/sq cm s introduced at distances of several solar radii to provide the high speed of the issuing solar wind. The traditional view has been that this energy is obtained from Alfven waves generated in the subphotospheric convection, which dissipate as they propagate outward, converting the wave energy into heat. This paper reviews the generation of waves and the known wave dissipation mechanisms, to show that the necessary Alfven waves are not produced under the conditions presently understood to exist in the sun, nor would such waves dissipate significantly in the first 1-2 solar radii if they existed. Wave dissipation occurs only over distances of the order of 5 solar radii or more.

  13. Solar Coronal Plumes

    Directory of Open Access Journals (Sweden)

    Giannina Poletto

    2015-12-01

    Full Text Available Polar plumes are thin long ray-like structures that project beyond the limb of the Sun polar regions, maintaining their identity over distances of several solar radii. Plumes have been first observed in white-light (WL images of the Sun, but, with the advent of the space era, they have been identified also in X-ray and UV wavelengths (XUV and, possibly, even in in situ data. This review traces the history of plumes, from the time they have been first imaged, to the complex means by which nowadays we attempt to reconstruct their 3-D structure. Spectroscopic techniques allowed us also to infer the physical parameters of plumes and estimate their electron and kinetic temperatures and their densities. However, perhaps the most interesting problem we need to solve is the role they cover in the solar wind origin and acceleration: Does the solar wind emanate from plumes or from the ambient coronal hole wherein they are embedded? Do plumes have a role in solar wind acceleration and mass loading? Answers to these questions are still somewhat ambiguous and theoretical modeling does not provide definite answers either. Recent data, with an unprecedented high spatial and temporal resolution, provide new information on the fine structure of plumes, their temporal evolution and relationship with other transient phenomena that may shed further light on these elusive features.

  14. The Coronal Monsoon: Thermal Nonequilibrium Revealed by Periodic Coronal Rain

    Science.gov (United States)

    Auchère, Frédéric; Froment, Clara; Soubrié, Elie; Antolin, Patrick; Oliver, Ramon; Pelouze, Gabriel

    2018-02-01

    We report on the discovery of periodic coronal rain in an off-limb sequence of Solar Dynamics Observatory/Atmospheric Imaging Assembly images. The showers are co-spatial and in phase with periodic (6.6 hr) intensity pulsations of coronal loops of the sort described by Auchère et al. and Froment et al. These new observations make possible a unified description of both phenomena. Coronal rain and periodic intensity pulsations of loops are two manifestations of the same physical process: evaporation/condensation cycles resulting from a state of thermal nonequilibrium. The fluctuations around coronal temperatures produce the intensity pulsations of loops, and rain falls along their legs if thermal runaway cools the periodic condensations down and below transition-region temperatures. This scenario is in line with the predictions of numerical models of quasi-steadily and footpoint heated loops. The presence of coronal rain—albeit non-periodic—in several other structures within the studied field of view implies that this type of heating is at play on a large scale.

  15. Sagittal crest formation in great apes and gibbons.

    Science.gov (United States)

    Balolia, Katharine L; Soligo, Christophe; Wood, Bernard

    2017-06-01

    The frequency of sagittal crest expression and patterns of sagittal crest growth and development have been documented in hominoids, including some extinct hominin taxa, and the more frequent expression of the sagittal crest in males has been traditionally linked with the need for larger-bodied individuals to have enough attachment area for the temporalis muscle. In the present study, we investigate sagittal cresting in a dentally mature sample of four hominoid taxa (Pan troglodytes schweinfurthii, Gorilla gorilla gorilla, Pongo pygmaeus pygmaeus and Hylobates lar). We investigate whether sagittal crest size increases with age beyond dental maturity in males and females of G. g. gorilla and Po. pyg. pygmaeus, and whether these taxa show sex differences in the timing of sagittal crest development. We evaluate the hypothesis that the larger sagittal crest of males may not be solely due to the requirement for a larger surface area than the un-crested cranial vault can provide for the attachment of the temporalis muscle, and present data on sex differences in temporalis muscle attachment area and sagittal crest size relative to cranial size. Gorilla g. gorilla and Po. pyg. pygmaeus males show significant relationships between tooth wear rank and sagittal crest size, and they show sagittal crest size differences between age groups that are not found in females. The sagittal crest emerges in early adulthood in the majority of G. g. gorilla males, whereas the percentage of G. g. gorilla females possessing a sagittal crest increases more gradually. Pongo pyg. pygmaeus males experience a three-fold increase in the number of specimens exhibiting a sagittal crest in mid-adulthood, consistent with a secondary growth spurt. Gorilla g. gorilla and Po. pyg. pygmaeus show significant sex differences in the size of the temporalis muscle attachment area, relative to cranial size, with males of both taxa showing positive allometry not shown in females. Gorilla g

  16. An interactive tool for CT volume rendering and sagittal plane-picking of the prostate for radiotherapy treatment planning

    International Nuclear Information System (INIS)

    Jani, Ashesh B.; Pelizzari, Charles A.; Chen, George T.Y.; Grzezcszuk, Robert P.; Vijayakumar, Srinivasan

    1997-01-01

    Objective: Accurate and precise target volume and critical structure definition is a basic necessity in radiotherapy. The prostate, particularly the apex (an important potential site of recurrence in prostate cancer patients), is a challenging structure to define using any modality, including conventional axial CT. Invasive or expensive techniques, such as retrograde urethrography or MRI, could be avoided if localization of the prostate were possible using information already available on the planning CT. Our primary objective was to build a software tool to determine whether volume rendering and sagittal plane-picking, which are CT-based, noninvasive visualization techniques, were of utility in radiotherapy treatment planning for the prostate. Methods: Using AVS (Application Visualization System) on a Silicon Graphics Indigo 2 High Impact workstation, we have developed a tool that enables the clinician to efficiently navigate a CT volume and to use volume rendering and sagittal plane-picking to better define structures at any anatomic site. We applied the tool to the specific example of the prostate to compare the two visualization techniques with the current standard of axial CT. The prostate was defined on 80-slice CT scans (scanning thickness 4mm, pixel size 2mm x 2mm) of prostate cancer patients using axial CT images, volume-rendered CT images, and sagittal plane-picked images. Results: The navigation of the prostate using the different visualization techniques qualitatively demonstrated that the sagittal plane-picked images, and even more so the volume-rendered images, revealed the prostate (particularly the lower border) better in relationship to the surrounding regional anatomy (bladder, rectum, pelvis, and penile structures) than did the axial images. A quantitative comparison of the target volumes obtained by navigating using the different visualization techniques demonstrated that, when compared to the prostate volume defined on axial CT, a larger volume

  17. MRI evaluation of myometrial invasion by endometrial carcinoma. Comparison between fast-spin-echo T2W and coronal FMPSPGR Gadolinium-Dota-Enhanced Sequences

    International Nuclear Information System (INIS)

    Nasi, Francesca; Fiocchi, Federica; Pecchi, Annarita; Torricelli, Pietro; Rivasi, Francesco

    2005-01-01

    Purpose. The depth of myometrial invasion by endometrial carcinoma strongly affects the incidence of metastasis to regional nodes and influences the surgical strategies. The aim of this paper is to compare the results of FSE T2-w and Gadolinium-enhanced FMPSGR MR sequences in assessing the depth of myometrial invasion by endometrial cancer. Materials and methods. Forty-five women with histopathologically-proven endometrial carcinoma underwent preoperative MRI. Axial SE TI w, axial, sagittal and para-coronal FSE T2w and para-coronal Gadolinium enhanced FMPSGR sequences were performed using a high field strength magnet (1.5T). Within one month of MR all patients underwent hysterectomy, and anatomical evaluation of the surgical specimen was done sectioning the uterus along the short axis. Based upon the results of the histological evaluation the results of the FSE T2w and Gadolinium-enhanced sequences were compared and the statistical difference between the results obtained was statistically evaluated. Results. The histological evaluation showed intra mucosal neoplasm in 11 patients, myometrial infiltration less than 50% in 31 patients, myometrial infiltration more than 50% in 12 patients and transmural cancer 1 patient. Statistical evaluation showed that the FSE T2w sequence had a global sensitivity and specificity of 80.6% and 87.6%, respectively, with a mean Negative Predictive Value of 92.6% and a mean Positive Predictive Value of 86%. Gadolinium-enhanced FMPSPGR sequence had a global sensitivity and specificity of 90.6% and 93.3%, respectively, with a mean Negative Predictive Value of 96,3% and a mean Positive Predictive Value of 88%. The staging accuracy (χ 2 test) on FMPSPGR images (95%) was higher than that on FSE T2w images (78%). Conclusions. In our experience Gadolinium-enhanced dynamic sequences increase the accuracy of MR imaging in diagnosing the depth of myometrial invasion. In particular they improve the visualisation of the inner myometrium, the so

  18. Tridimensional Analysis of Rotatory Subluxation and Sagittal Spinopelvic Alignment in the Setting of Adult Spinal Deformity.

    Science.gov (United States)

    Ferrero, Emmanuelle; Lafage, Renaud; Diebo, Bassel G; Challier, Vincent; Illharreborde, Brice; Schwab, Frank; Skalli, Wafa; Guigui, Pierre; Lafage, Virginie

    2017-07-01

    Retrospective single-center. To investigate rotatory subluxation (RS) in adult spinal deformity (ASD) with three-dimensional (3D) stereoradiographic images and analyze relationships between RS, transverse plane parameters, spinopelvic parameters, and clinical outcomes. Recent research has demonstrated that sagittal plane malalignment and listhesis correlate with ASD patient-reported outcomes. However, there is still a lack of knowledge regarding the clinical impact of 3D evaluation and rotatory subluxation. Recent developments in stereoradiography allow clinicians to obtain full-body standing radiographs with low-dose radiation and 3D reconstruction. One hundred thirty lumbar ASD patients underwent full-spine biplanar radiographs (EOS Imaging, Paris, France). Clinical outcomes were recorded. Using sterEOS software, spinopelvic parameters and lateral listhesis were measured. 3D transverse plane parameters included apical axial vertebral rotation, axial intervertebral rotation (AIR), and torsion index (sum of AIR in the curve). ASD patients were divided in three groups: AIR 10°. Groups were compared with respect to radiographic and clinical data. Correlations were performed between the transverse and sagittal plane parameters and clinical outcomes. Patients with AIR >10° were significantly older, with larger Cobb angle (39.5°) and greater sagittal plane deformity (pelvic incidence-lumbar lordosis mismatch 11.7° and pelvic tilt 22.6°). The AIR >10° group had significantly greater apical vertebra axial rotation apex (24.8°), torsion index (45°), and upper-level AIR (21.5°) than the two other groups. Overall, 27% of AIR patients did not have two-dimensional (2D) lateral listhesis. Patients with AIR >10° had significantly worse Oswestry Disability Index and more low back pain. For patients in which lateral listhesis was unreadable in 2D imaging, rotatory subluxation was revealed using stereoradiography and at an earlier disease stage. Moreover, different 3D

  19. Observational Analysis of Coronal Fans

    Science.gov (United States)

    Talpeanu, D.-C.; Rachmeler, L; Mierla, Marilena

    2017-01-01

    Coronal fans (see Figure 1) are bright observational structures that extend to large distances above the solar surface and can easily be seen in EUV (174 angstrom) above the limb. They have a very long lifetime and can live up to several Carrington rotations (CR), remaining relatively stationary for many months. Note that they are not off-limb manifestation of similarly-named active region fans. The solar conditions required to create coronal fans are not well understood. The goal of this research was to find as many associations as possible of coronal fans with other solar features and to gain a better understanding of these structures. Therefore, we analyzed many fans and created an overview of their properties. We present the results of this statistical analysis and also a case study on the longest living fan.

  20. Coronal Mass Ejections An Introduction

    CERN Document Server

    Howard, Timothy

    2011-01-01

    In times of growing technological sophistication and of our dependence on electronic technology, we are all affected by space weather. In its most extreme form, space weather can disrupt communications, damage and destroy spacecraft and power stations, and increase radiation exposure to astronauts and airline passengers. Major space weather events, called geomagnetic storms, are large disruptions in the Earth’s magnetic field brought about by the arrival of enormous magnetized plasma clouds from the Sun. Coronal mass ejections (CMEs) contain billions of tons of plasma and hurtle through space at speeds of several million miles per hour. Understanding coronal mass ejections and their impact on the Earth is of great interest to both the scientific and technological communities. This book provides an introduction to coronal mass ejections, including a history of their observation and scientific revelations, instruments and theory behind their detection and measurement, and the status quo of theories describing...

  1. Persistent axial neck pain after cervical disc arthroplasty: a radiographic analysis.

    Science.gov (United States)

    Wagner, Scott C; Formby, Peter M; Kang, Daniel G; Van Blarcum, Gregory S; Cody, John P; Tracey, Robert W; Lehman, Ronald A

    2016-07-01

    There is very little literature examining optimal radiographic parameters for placement of cervical disc arthroplasty (CDA), nor is there substantial evidence evaluating the relationship between persistent postoperative neck pain and radiographic outcomes. We set out to perform a single-center evaluation of the radiographic outcomes, including associated complications, of CDA. This is a retrospective review. Two hundred eighty-five consecutive patients undergoing CDA were included in the review. The outcome measures were radiological parameters (preoperative facet arthrosis, disc height, CDA placement in sagittal and coronal planes, heterotopic ossification [HO] formation, etc.) and patient outcomes (persistent pain, recurrent pain, new-onset pain, etc.). We performed a retrospective review of all patients from a single military tertiary medical center from August 2008 to August 2012 undergoing CDA. Preoperative, immediate postoperative, and final follow-up films were evaluated. The clinical outcomes and complications associated with the procedure were also examined. The average radiographic follow-up was 13.5 months and the rate of persistent axial neck pain was 17.2%. For patients with persistent neck pain, the rate of HO formation per level studied was 22.6%, whereas the rate was significantly lower for patients without neck pain (11.7%, p=.03). There was no significant association between the severity of HO and the presence of neck pain. Patients with a preoperative diagnosis of cervicalgia, compared to those without cervicalgia, were significantly more likely to experience continued neck pain postoperatively (28.6% vs. 13.1%, p=.01). There were no differences in preoperative facet arthrosis, pre- or postoperative disc height, segmental range of motion, or placement of the device relative to the posterior edge of the vertebral body.However, patients with implants more centered between the uncovertebral joints were more likely to experience posterior neck pain

  2. Sagittal synostosis: I. Preoperative morphology of the skull

    DEFF Research Database (Denmark)

    Guimaraes-Ferreira, J.; Gewalli, F.; David, L.

    2006-01-01

    The aim of this study was to characterise the preoperative morphology of the skull in sagittal synostosis in an objective and quantified way. The shapes of the skulls of 105 patients with isolated premature synostosis of the sagittal suture ( SS group) were studied and compared with those of a co...

  3. Superior sagittal sinus thrombosis: a rare complication of nephrotic syndrome.

    Directory of Open Access Journals (Sweden)

    Tullu M

    1999-10-01

    Full Text Available A two and half year-old-male child, known case of steroid responsive nephrotic syndrome presented with fever and vomiting of acute onset. He was diagnosed to have superior sagittal sinus thrombosis on a contrast computerised tomographic scan of brain. Recovery was complete without anticoagulant therapy. Superior sagittal sinus thrombosis is an extremely rare complication of nephrotic syndrome.

  4. Craniotomy of the Fused Sagittal Suture Over the Superior Sagittal Sinus Is a Safe Procedure.

    Science.gov (United States)

    Kölby, David; Fischer, Sara; Arab, Khalid; Maltese, Giovanni; Olsson, Robert; Paganini, Anna; Tarnow, Peter; Kölby, Lars

    2017-05-01

    Spring-assisted cranioplasty to correct sagittal synostosis is based on midline craniotomy through the closed sagittal suture, over the superior sagittal sinus (SSS). The aim of the present study was to evaluate the perioperative safety of this technique. This is a retrospective study of all patients operated with median craniotomy and springs from 1998 to the end of 2015. For comparison, all Pi-plasties performed during the same time interval were also evaluated. The safety measures were evaluated based on incidence of damage to SSS, incidence of dural tears, perioperative blood loss, operative time, and hospital stay. In the group that had undergone midline craniotomy combined with springs (n = 225), 4 perioperative damages to SSS and 1 dural tear were seen. The perioperative blood loss was 62.8 ± 65.3 mL (mean ± standard deviation). The operative time was 67.9 ± 21.5 minutes and the hospital stay was 4.8 ± 1.1 days. In the group that had undergone pi-plasty (n = 105), no damages to SSS but 3 dural tears were seen. The perioperative blood loss was 352.8 ± 174.4 mL. The operative time was 126.0 ± 31.7 minutes and the hospital stay was 7.1 ± 1.4 days. Craniotomy SSS in sagittal synostosis is a safe procedure with low morbidity in terms of damage to the SSS. Midline craniotomy combined with springs has significantly lower preoperative blood loss, operative time, and hospital stay (P < 0.001 for all) compared to pi-plasty.

  5. Dynamics of Coronal Hole Boundaries

    International Nuclear Information System (INIS)

    Higginson, A. K.; Zurbuchen, T. H.; Antiochos, S. K.; DeVore, C. R.; Wyper, P. F.

    2017-01-01

    Remote and in situ observations strongly imply that the slow solar wind consists of plasma from the hot, closed-field corona that is released onto open magnetic field lines. The Separatrix Web theory for the slow wind proposes that photospheric motions at the scale of supergranules are responsible for generating dynamics at coronal-hole boundaries, which result in the closed plasma release. We use three-dimensional magnetohydrodynamic simulations to determine the effect of photospheric flows on the open and closed magnetic flux of a model corona with a dipole magnetic field and an isothermal solar wind. A rotational surface motion is used to approximate photospheric supergranular driving and is applied at the boundary between the coronal hole and helmet streamer. The resulting dynamics consist primarily of prolific and efficient interchange reconnection between open and closed flux. The magnetic flux near the coronal-hole boundary experiences multiple interchange events, with some flux interchanging over 50 times in one day. Additionally, we find that the interchange reconnection occurs all along the coronal-hole boundary and even produces a lasting change in magnetic-field connectivity in regions that were not driven by the applied motions. Our results show that these dynamics should be ubiquitous in the Sun and heliosphere. We discuss the implications of our simulations for understanding the observed properties of the slow solar wind, with particular focus on the global-scale consequences of interchange reconnection.

  6. The dynamics of coronal magnetic structures

    International Nuclear Information System (INIS)

    Weber, W.

    1978-01-01

    An analysis is made of the evolution of coronal magnetic fields due to the interaction with the solar wind. An analysis of the formation of coronal streamers, arising as a result of the stretching of bipolar fields, is given. Numerical simulations of the formation of coronal streamers are presented. Fast-mode shocks as triggers of microturbulence in the solar corona are discussed

  7. Effect of the Coronal Wall Thickness of Dental Implants on the Screw Joint Stability in the Internal Implant-Abutment Connection.

    Science.gov (United States)

    Lee, Ji-Hye; Huh, Yoon-Hyuk; Park, Chan-Jin; Cho, Lee-Ra

    2016-01-01

    To evaluate the effect of implant coronal wall thickness on load-bearing capacity and screw joint stability. Experimental implants were customized after investigation of the thinnest coronal wall thickness of commercially available implant systems with a regular platform diameter. Implants with four coronal wall thicknesses (0.2, 0.3, 0.4, and 0.5 mm) were fabricated. Three sets of tests were performed. The first set was a failure test to evaluate load-bearing capacity and elastic limit. The second and third sets were cyclic and static loading tests. After abutment screw tightening of each implant, vertical cyclic loading of 250 N or static loading from 250 to 800 N was applied. Coronal diameter expansion, axial displacement, and removal torque values of the implants were compared. Repeated measures analysis of variance (ANOVA) was used for statistical analysis (α = .05). Implants with 0.2-mm coronal wall thickness demonstrated significantly low load-bearing capacity and elastic limit (both P implants also showed significantly large coronal diameter expansion and axial displacement after screw tightening (both P implant, axial displacement of the abutment, and removal torque loss of the abutment screw (all P Implant coronal wall thickness of 0.2 mm produces significantly inferior load-bearing capacity and screw joint stability.

  8. Changing Sagittal-Plane Landing Styles to Modulate Impact and Tibiofemoral Force Magnitude and Directions Relative to the Tibia

    Science.gov (United States)

    Shimokochi, Yohei; Ambegaonkar, Jatin P.; Meyer, Eric G.

    2016-01-01

    Context: Ground reaction force (GRF) and tibiofemoral force magnitudes and directions have been shown to affect anterior cruciate ligament loading during landing. However, the kinematic and kinetic factors modifying these 2 forces during landing are unknown. Objective: To clarify the intersegmental kinematic and kinetic links underlying the alteration of the GRF and tibiofemoral force vectors secondary to changes in the sagittal-plane body position during single-legged landing. Design: Crossover study. Setting: Laboratory. Patients or Other Participants: Twenty recreationally active participants (age = 23.4 ± 3.6 years, height = 171.0 ± 9.4 cm, mass = 73.3 ± 12.7 kg). Intervention(s): Participants performed single-legged landings using 3 landing styles: self-selected landing (SSL), body leaning forward and landing on the toes (LFL), and body upright with flat-footed landing (URL). Three-dimensional kinetics and kinematics were recorded. Main Outcome Measure(s): Sagittal-plane tibial inclination and knee-flexion angles, GRF magnitude and inclination angles relative to the tibia, and proximal tibial forces at peak tibial axial forces. Results: The URL resulted in less time to peak tibial axial forces, smaller knee-flexion angles, and greater magnitude and a more anteriorly inclined GRF vector relative to the tibia than did the SSL. These changes led to the greatest peak tibial axial and anterior shear forces in the URL among the 3 landing styles. Conversely, the LFL resulted in longer time to peak tibial axial forces, greater knee-flexion angles, and reduced magnitude and a more posteriorly inclined GRF vector relative to the tibia than the SSL. These changes in LFL resulted in the lowest peak tibial axial and largest posterior shear forces among the 3 landing styles. Conclusions: Sagittal-plane intersegmental kinematic and kinetic links strongly affected the magnitude and direction of GRF and tibiofemoral forces during the impact phase of single-legged landing

  9. Axial static mixer

    Science.gov (United States)

    Sandrock, H.E.

    1982-05-06

    Static axial mixing apparatus includes a plurality of channels, forming flow paths of different dimensions. The axial mixer includes a flow adjusting device for adjustable selective control of flow resistance of various flow paths in order to provide substantially identical flows through the various channels, thereby reducing nonuniform coating of interior surfaces of the channels. The flow adjusting device may include diaphragm valves, and may further include a pressure regulating system therefor.

  10. The Coronal Place; Why is It Special?

    Directory of Open Access Journals (Sweden)

    Azhar Alkazwini

    2017-10-01

    Full Text Available To prove the existence of arguments about the exact place that can bear the term ‘coronal’, it would be enough to check the explanatory dictionary’s entry. There are different arguments regarding the exact place of coronal. In this paper, some of the linguistic evidence regarding the coronal place shall be mentioned. Then, I shall discuss the classes of coronal that lend support to the fact that coronal place is believed to be special, and that is by discussing the different typologies of coronal consonants and giving their description.

  11. HST STIS Coronal Iron Survey

    Science.gov (United States)

    Ayres, T. R.; Brown, A.; Linsky, J. L.

    2001-05-01

    The broad coverage, high sensitivity, and precise wavelength calibration of the Space Telescope Imaging Spectrograph's medium-resolution echelle mode, coupled with the growing collection of GO and GTO E140M exposures, are ideal for surveys of specific spectral diagnostics across a diversity of stellar types, luminosities, and activity levels. Of great current interest are the weak coronal forbidden lines that appear in the far-UV, which are well known from solar flare work. Measuring coronal lines with STIS in the 1150--1700 Å band has significant advantages over using, say, Chandra HETGS or XMM-Newton RGS in the 1 keV range, because the STIS velocity resolution is 40x, or more, higher; STIS has an absolute wavelength calibration established by an onboard emission lamp; and the large effective area of the HST telescope compensates for the faintness of the forbidden lines. Here, we report a survey of Fe XXI λ 1354 in a sample of ~25 stars. The forbidden iron feature forms at a temperature of about 107 K, characteristic of very active or flaring coronal conditions. Clear detections of the coronal iron line are made in active M dwarfs (AU Mic, AD Leo), active giants (α Aur, β Cet, ι Cap, 24 UMa, HR 9024), short-period RS CVn binaries (e.g., HR 1099), and possibly in active solar-type dwarfs (ζ Dor, χ1 Ori). We describe our semi-empirical method for removing the C I blend that partially corrupts the Fe XXI profile, and our measurements of coronal line widths and Doppler shifts. Although α Aur displays clear variability between Fe XXI profiles obtained at the same orbital phase, but four years apart; the hyperactive HR 1099 system showed virtually no change in its coronal iron feature during a sequence of 14 spectra taken over a 7 hr period in 1999 September, despite the occurrence of two large flares in far-UV lines such as Si IV and C IV. This work was supported by grant GO-08280.01-97A from STScI. Observations were from the NASA/ESA HST, collected at the STSc

  12. FUNCTIONAL DISABILITY, SAGITTAL ALIGNMENT AND PELVIC BALANCE IN LUMBAR SPONDYLOLISTHESIS

    Directory of Open Access Journals (Sweden)

    Luis Muñiz Luna

    2016-03-01

    Full Text Available ABSTRACT Objectives: To demonstrate the recovery of lumbar sagittal pelvic alignment and sagittal pelvic balance after surgical reduction of lumbar spondylolisthesis and establish the benefits of the surgery for reduction and fixation of the lumbar spondylolisthesis with 360o circumferential arthrodesis for 2 surgical approaches by clinical and functional evaluation. Method: Eight patients with lumbar spondylolisthesis treated with surgical reduction and fixation of listhesis and segmental circumferential fusion with two surgical approaches were reviewed. They were evaluated before and after treatment with Oswestry, Visual Analogue for pain and Odom scales, performing radiographic measurement of lumbar sagittal alignment and pelvic sagittal balance with the technique of pelvic radius. Results: Oswestry scales and EVA reported improvement of symptoms after treatment in 8 cases; the Odom scale had six outstanding cases reported. The lumbar sagittal alignment presented a lumbosacral lordosis angle and a lumbopelvic lordosis angle reduced in 4 cases and increased in 4 other cases; pelvic sagittal balance increased the pelvic angle in 4 cases and decreased in 3 cases and the sacral translation of the hip axis to the promontory increased in 6 cases. Conclusion: The surgical procedure evaluated proved to be useful by modifying the lumbar sagittal alignment and the pelvic balance, besides reducing the symptoms, enabling the patient to have mobility and movement and the consequent satisfaction with the surgery.

  13. Sagittal Abdominal Diameter: Application in Clinical Practice

    Directory of Open Access Journals (Sweden)

    Thaís Da Silva-Ferreira

    2014-05-01

    Full Text Available Excess visceral fat is associated with cardiovascular risk factors. Sagittal abdominal diameter (SAD has recently been highlighted as an indicator of abdominal obesity, and also may be useful in predicting cardiovascular risk. The purpose of the present study was to review the scientific literature on the use of SAD in adult nutritional assessment. A search was conducted for scientific articles in the following electronic databases: SciELO , MEDLINE (PubMed and Virtual Health Library. SAD is more associated with abdominal fat (especially visceral, and with different cardiovascular risk factors, such as, insulin resistance, blood pressure, and serum lipoproteins than the traditional methods of estimating adiposity, such as body mass index and waist-to-hip ratio. SAD can also be used in association with other anthropometric measures. There are still no cut-off limits established to classify SAD as yet. SAD can be an alternative measure to estimate visceral adiposity. However, the few studies on this diameter, and the lack of consensus on the anatomical site to measure SAD, are obstacles to establish cut-off limits to classify it.

  14. Polarization of Coronal Forbidden Lines

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hao; Qu, Zhongquan [Yunnan Observatories, Chinese Academy of Sciences, Kunming, Yunnan 650011 (China); Landi Degl’Innocenti, Egidio, E-mail: sayahoro@ynao.ac.cn [Dipartimento di Astronomia e Scienza dello Spazio, Università di Firenze, Largo E. Fermi 2, I-50125 Firenze (Italy)

    2017-03-20

    Since the magnetic field is responsible for most manifestations of solar activity, one of the most challenging problems in solar physics is the diagnostics of solar magnetic fields, particularly in the outer atmosphere. To this end, it is important to develop rigorous diagnostic tools to interpret polarimetric observations in suitable spectral lines. This paper is devoted to analyzing the diagnostic content of linear polarization imaging observations in coronal forbidden lines. Although this technique is restricted to off-limb observations, it represents a significant tool to diagnose the magnetic field structure in the solar corona, where the magnetic field is intrinsically weak and still poorly known. We adopt the quantum theory of polarized line formation developed in the framework of the density matrix formalism, and synthesize images of the emergent linear polarization signal in coronal forbidden lines using potential-field source-surface magnetic field models. The influence of electronic collisions, active regions, and Thomson scattering on the linear polarization of coronal forbidden lines is also examined. It is found that active regions and Thomson scattering are capable of conspicuously influencing the orientation of the linear polarization. These effects have to be carefully taken into account to increase the accuracy of the field diagnostics. We also found that linear polarization observation in suitable lines can give valuable information on the long-term evolution of the magnetic field in the solar corona.

  15. CORRELATION BETWEEN CERVICAL SAGITTAL ALIGNMENT AND FUNCTIONAL CAPACITY IN CERVICAL SPONDYLOSIS

    Directory of Open Access Journals (Sweden)

    Marcel Machado da Motta

    Full Text Available ABSTRACT Objective: To correlate the radiographic parameters of sagittal cervical alignment with quality of life and functional capacity in patients with cervical spondylosis under conservative treatment. Methods: This is an observational and prospective study in patients with cervical spondylosis under conservative treatment and without indication for surgery. The 52 patients included were divided into three groups: axial pain, radiculopathy, and cervical myelopathy. The radiographic parameters considered were cervical lordosis (CL, cervical sagittal vertical axis (CSVA, T1 slope (TS and the discrepancy between TS and CL (TS-CL. Quality of life and functional capacity were evaluated by the Neck Disability Index (NDI questionnaire. Pain was assessed by the Visual Analogue Scale (VAS. The correlation between the radiographic parameters and the clinical scores was evaluated by the Pearson correlations coefficient. Results: There was no difference in cervical radiographic parameters between the three groups. In the total of the sample, the mean value of the CSVA was 17.8o (±8.3o, CL, 22.4° (± 8.8°; TS, 29.3° (±6.6°, and TS-CL, 7.0° (±7.4°. Significant inverse correlation (r= -0.3, p=0.039 was observed between NDI and CL, but there was no significant correlation between CL and VAS. CSVA (p=0.541, TS (p=0.287 and TS-CL (p=0.287 had no significantly correlated with NDI or VAS. Conclusion: Considering patients with cervical spondylosis not candidates for surgery, the only sagittal parameter that correlated with functional capacity was LC. In these patients, the correlation between cervical alignment and quality of life needs to be better characterized.

  16. Self-Inflicted Drywall Screws in the Sagittal Sinus.

    Science.gov (United States)

    Guppy, Kern H; Ochi, Calvin

    2018-02-01

    A 30-year-old right-handed man with a history of schizophrenia presented with 2 self-inflicted drywall screws in the skull. The patient was sleepy but easily arousable; blood tests showed he had taken methamphetamines. Computed tomography and computed tomography angiography of the head showed the frontal screw abutted left of the superior sagittal sinus, and the posterior screw went through the superior sagittal sinus with no extravasation of contrast material at either site. Both screws were removed with exposure of the sagittal sinus using U-shaped craniectomies. There was no bleeding on the removal of the screws. It appears the posterior screw entered between the leaflets of the sagittal sinus dura mater. The patient had returned to work without any sequelae 1 month after injury. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Wrist CT and three-dimensional reconstruction: Direct coronal versus transaxial scanning

    International Nuclear Information System (INIS)

    Biondetti, P.R.; Vannier, M.W.; Gilula, L.A.; Knapp, R.H.

    1986-01-01

    Because of its three-dimensional complexity, the wrist cannot be completely examined radiographically without CT. Complex carpal fractures, intercarpal and distal radioulnar dislocations or subluxations, late sequelae of trauma (nonunion, osteonecrosis, degenerative changes, infections), and the painful wrist with normal plain film and abnormal bone scan appearance have been evaluated with CT. In the majority of cases reported in the literature, the wrist was scanned by CT in the transaxial plane. The author compared direct transaxial and coronal CT scanning in 23 patients with wrist disorders. Axial sections were superior for distal radioulnar subluxation, hamate hook fractures, and for the ventral trapezial tubercle not shown on routine radiographs. Coronal scanning, performed using a specially designed wrist fixture, was preferable for most other wrist CT examinations. Coronal wrist CT offers perpendicular orientation for the majority of the carpal joints, anatomic display similar to that of plain film radiography, and fewer scans per wrist CT examination. Three-dimensional surface reconstruction wrist images were better when coronal rather than transaxial scans were used as input. Direct coronal CT should be the method of choice for most patients with wrist problems

  18. Mid-sagittal plane and mid-sagittal surface optimization in brain MRI using a local symmetry measure

    DEFF Research Database (Denmark)

    Stegmann, Mikkel Bille; Skoglund, Karl; Ryberg, Charlotte

    2005-01-01

    , the mid-sagittal plane is not always planar, but a curved surface resulting in poor partitioning of the brain hemispheres. To account for this, this paper also investigates an optimization strategy which fits a thin-plate spline surface to the brain data using a robust least median of squares estimator....... Albeit computationally more expensive, mid-sagittal surface fitting demonstrated convincingly better partitioning of curved brains into cerebral hemispheres....

  19. Using Strong Solar Coronal Emission Lines as Coronal Flux Proxies

    Science.gov (United States)

    Falconer, David A.; Jordan, Studart D.; Davila, Joseph M.; Thomas, Roger J.; Andretta, Vincenzo; Brosius, Jeffrey W.; Hara, Hirosha

    1997-01-01

    A comparison of Skylab results with observations of the strong EUV lines of Fe XVI at 335 A and 361 A from the Goddard Solar EUV Rocket Telescope and Spectrograph (SERTS) flight of 1989 suggests that these lines, and perhaps others observed with SERTS, might offer good proxies for estimating the total coronal flux over important wavelength ranges. In this paper, we compare SERTS observations from a later, 1993 flight with simultaneous cospatial Yohkoh soft X-ray observations to test this suggestion over the energy range of the Soft X-ray Telescope (SXT) on Yohkoh. Both polynomial and power-law fits are obtained, and errors are estimated, for the SERTS lines of Fe XVI 335 A and 361 A, Fe XV 284 A and 417 A, and Mg IX 368 A. It is found that the power-law fits best cover the full range of solar conditions from quiet Sun through active region, though not surprisingly the 'cooler' Mg IX 368 A line proves to be a poor proxy. The quadratic polynomial fits yield fair agreement over a large range for all but the Mg IX line, but the linear fits fail conspicuously when extrapolated into the quiet Sun regime. The implications of this work for the He 11 304 A line formation problem are briefly considered. The paper concludes with a discussion of the value of these iron lines observed with SERTS for estimating stellar coronal fluxes, as observed for example with the EUVE satellite.

  20. Sagittal otolith morphogenesis asymmetry in marine fishes.

    Science.gov (United States)

    Mille, T; Mahe, K; Villanueva, M C; De Pontual, H; Ernande, B

    2015-09-01

    This study investigated and compared asymmetry in sagittal otolith shape and length between left and right inner ears in four roundfish and four flatfish species of commercial interest. For each species, the effects of ontogenetic changes (individual age and total body length), sexual dimorphism (individual sex) and the otolith's location on the right or left side of the head, on the shape and length of paired otoliths (between 143 and 702 pairs according to species) were evaluated. Ontogenetic changes in otolith shape and length were observed for all species. Sexual dimorphism, either in otolith shape and length or in their ontogenetic changes, was detected for half of the species, be they round or flat. Significant directional asymmetry in otolith shape and length was detected in one roundfish species each, but its inconsistency across species and its small average amplitude (6·17% for shape and 1·99% for length) suggested that it has barely any biological relevance. Significant directional asymmetry in otolith shape and length was found for all flatfish species except otolith length for one species. Its average amplitude varied between 2·06 and 17·50% for shape and between 0·00 and 11·83% for length and increased significantly throughout ontogeny for two species, one dextral and one sinistral. The longer (length) and rounder otolith (shape) appeared to be always on the blind side whatever the species. These results suggest differential biomineralization between the blind and ocular inner ears in flatfish species that could result from perturbations of the proximal-distal gradient of otolith precursors in the endolymph and the otolith position relative to the geometry of the saccular epithelium due to body morphology asymmetry and lateralized behaviour. The fact that asymmetry never exceeded 18% even at the individual level suggests an evolutionary canalization of otolith shape symmetry to avoid negative effects on fish hearing and balance. Technically

  1. A Comparative Study of Sagittal Balance in Patients with Neuromuscular Scoliosis

    Directory of Open Access Journals (Sweden)

    Paulo Alvim Borges

    Full Text Available OBJECTIVES: Spinopelvic alignment has been associated with improved quality of life in patients with vertebral deformities, and it helps to compensate for imbalances in gait. Although surgical treatment of scoliosis in patients with neuromuscular spinal deformities promotes correction of coronal scoliotic deformities, it remains poorly established whether this results in large changes in sagittal balance parameters in this specific population. The objective of this study is to compare these parameters before and after the current procedure under the hypothesis is that there is no significant modification. METHODS: Sampling included all records of patients with neuromuscular scoliosis with adequate radiographic records treated at Institute of Orthopedics and Traumatology of Clinics Hospital of University of São Paulo (IOT-HCFMUSP from January 2009 to December 2013. Parameters analyzed were incidence, sacral inclination, pelvic tilt, lumbar lordosis, thoracic kyphosis, spinosacral angle, spinal inclination and spinopelvic inclination obtained using the iSite-Philips digital display system with Surgimap and a validated method for digital measurements of scoliosis radiographs. Comparison between the pre- and post-operative conditions involved means and standard deviations and the t-test. RESULTS: Based on 101 medical records only, 16 patients met the inclusion criteria for this study, including 7 males and 9 females, with an age range of 9-20 and a mean age of 12.9±3.06; 14 were diagnosed with cerebral palsy. No significant differences were found between pre and postoperative parameters. CONCLUSIONS: Despite correction of coronal scoliotic deformity in patients with neuromuscular deformities, there were no changes in spinopelvic alignment parameters in the group studied.

  2. Axial tomographic scanner

    International Nuclear Information System (INIS)

    1976-01-01

    An axial tomographic system is described comprising axial tomographic means for collecting sets of data corresponding to the transmission or absorption of a number of beams of penetrating radiation through a planar slice of an object. It includes means to locate an object to be analyzed, a source and detector for directing one or more beams of penetrating radiation through the object from the source to the detector, and means to rotate (and optionally translate) the source as well as means to process the collected sets of data. Data collection, data processing, and data display can each be conducted independently of each other. An additional advantage of the system described is that the raw data (i.e., the originally collected data) are not destroyed by the data processing but instead are retained intact for further reference or use, if needed

  3. Methods of Temperature and Emission Measure Determination of Coronal Loops

    Science.gov (United States)

    Cirtain, J. W.; Schmelz, J. T.; Martens, P. C. H.

    2002-05-01

    Recent observational results from both SOHO-EIT and TRACE indicate that coronal loops are isothermal along their length (axially). These results are obtained from a narrowband filter ratio method that assumes that the plasma is isothermal along the line of sight (radially). However, these temperatures vary greatly from those derived from differential emission measure (DEM) curves produced from spectral lines recorded by SOHO-CDS. The DEM results indicate that the loops are neither axially nor radially isothermal. This discrepancy was investigated by Schmelz et al. (2001). They chose pairs of iron lines from the same CDS data set to mimic the EIT and TRACE loop results. Ratios of different lines gave different temperatures, indicating that the plasma was not radially isothermal. In addition the results indicated that the loop was axially isothermal, even though the DEM analysis of the same data showed this result to be false. Here we have analyzed the EIT data for the CDS loop published by Schmelz et al. (2001). We took the ratios of the 171-to-195 and 195-to-284 filter data, and made temperature maps of the loop. The results indicate that the loop is axially isothermal, but different temperatures were found for each pair of filters. Both ratio techniques force the resultant temperature to lie within the range where the response functions (for filters) or the emissivity functions (for lines) overlap; isothermal loops are therefore a byproduct of the analysis. This conclusion strengthens support for the idea that temperature and emission measure results from filter ratio methods may be misleading or even drastically wrong. This research was funded in part by the NASA/TRACE MODA grant for Montana State University. Solar physics research at the University of Memphis is supported by NASA grant NAG5-9783.

  4. Frontoorbital advancement in coronal suture craniosynostosis: a ...

    African Journals Online (AJOL)

    degree of frontoorbital advancement in treatment of coronal craniosynostosis. Patients and methods ... reshaping for treatment of bilateral and unilateral coronal craniosynostosis achieve excellent functional and ..... developed pulmonary edema and heart failure 1 day after surgery most probably because of fluid overload.

  5. Microwave Enhancement in Coronal Holes: Statistical Properties

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Astrophysics and Astronomy; Volume 21; Issue 3-4. Microwave Enhancement in Coronal Holes: Statistical Properties. Ν. Gopalswamy Κ. Shibasaki Μ. Salem. Session X – Cycle Variation in the Quiet Corona & Coronal Holes Volume 21 Issue 3-4 September-December 2000 pp 413-417 ...

  6. A systematic review of the angular values obtained by computerized photogrammetry in sagittal plane: a proposal for reference values.

    Science.gov (United States)

    Krawczky, Bruna; Pacheco, Antonio G; Mainenti, Míriam R M

    2014-05-01

    Reference values for postural alignment in the coronal plane, as measured by computerized photogrammetry, have been established but not for the sagittal plane. The objective of this study is to propose reference values for angular measurements used for postural analysis in the sagittal plane for healthy adults. Electronic databases (PubMed, BVS, Cochrane, Scielo, and Science Direct) were searched using the following key words: evaluation, posture, photogrammetry, and software. Articles published between 2006 and 2012 that used the PAS/SAPO (postural assessment software) were selected. Another inclusion criterion was the presentation of, at least, one of the following measurements: head horizontal alignment, pelvic horizontal alignment, hip angle, vertical alignment of the body, thoracic kyphosis, and lumbar lordosis. Angle samples of the selected articles were grouped 2 by 2 in relation to an overall average, which made possible total average, variance, and SD calculations. Six articles were included, and the following average angular values were found: 51.42° ± 4.87° (head horizontal alignment), -12.26° ± 5.81° (pelvic horizontal alignment), -6.40° ± 3.86° (hip angle), and 1.73° ± 0.94° (vertical alignment of the body). None of the articles contained the measurements for thoracic kyphosis and lumbar lordosis. The reference values can be adopted as reference for postural assessment in future researches if the same anatomical points are considered. Copyright © 2014 National University of Health Sciences. Published by Mosby, Inc. All rights reserved.

  7. The influence of computer-assisted surgery on rotational, coronal and sagittal alignment in revision total knee arthroplasty

    NARCIS (Netherlands)

    Meijer, Marrigje F; Stevens, Martin; Boerboom, Alexander L; Bulstra, Sjoerd K; Reininga, Inge Hf

    2014-01-01

    Background: Despite good results of primary total knee arthroplasty (TKA), the number of revision total knee arthroplasties (rTKAs) is rising. Proper implant position is essential, since malposition leads to worse clinical outcome. In rTKA most anatomical landmarks have disappeared because of

  8. Diffraction crystals for sagittally focusing x-rays

    Science.gov (United States)

    Ice, G.E.; Sparks, C.J. Jr.

    1982-06-07

    The invention is a new type of diffraction crystal designed for sagittally focusing photons of various energies. The invention is based on the discovery that such focusing is not obtainable with conventional crystals because of distortion resulting from anticlastic curvature. The new crystal comprises a monocrystalline base having a front face contoured for sagittally focusing photons and a back face provided with rigid, upstanding, stiffening ribs restricting anticlastic curvature. When mounted in a suitable bending device, the reflecting face of the crystal can be adjusted to focus photons having any one of a range of energies.

  9. Pedicle subtraction osteotomy in elderly patients with degenerative sagittal imbalance.

    Science.gov (United States)

    Cho, Kyu-Jung; Kim, Ki-Tack; Kim, Whoan-Jeang; Lee, Sang-Hoon; Jung, Jae-Hoon; Kim, Young-Tae; Park, Hae-Bong

    2013-11-15

    Retrospective, radiographical analysis. To evaluate pedicle subtraction osteotomy (PSO) as a means of correcting severe degenerative sagittal imbalance in elderly patients. PSO in patients with degenerative sagittal imbalance is likely to cause more complications than in patients with iatrogenic flatback deformity. This study analyzed 34 patients who underwent fusion to the sacrum, with a minimum 2-year follow-up. Age of the patients were in the range from 58 to 73 with the mean at 65.5 years. PSO was performed at one segment in all cases, consisting of L3 (n = 26), L4 (n = 4), L2 (n = 3), and L1 (n = 1). The average number of levels fused was 8.15. Ten patients had structural interbody fusion at the lumbosacral junction. Applying PSO at one segment, the mean correction of the lordotic angle at the osteotomy site was 33.3°, of which the loss of correction (LOC) was 4.0° at the last visit. The correction of lumbar lordosis was 33.7° and the LOC was 8.5°. The sagittal C7 plumb was 215.9 mm before surgery, corrected to 35.1 mm after surgery, and changed to 95.9 mm by the last visit. The correction of the sagittal C7 plumb was 119.9 mm and the LOC was 60.9 mm. There was substantial LOC in lumbar lordosis and sagittal C7 plumb. In 10 patients with addition of posterior lumbar interbody fusion, the LOC of lumbar lordosis was 7.4°, which was less than 9° in those without it. PSO for the correction of degenerative sagittal imbalance in elderly patients resulted in correction of sagittal alignment with a significant LOC of lumbar lordosis and sagittal C7 plumb. The LOC of lumbar lordosis occurred at both the osteotomy and non-osteotomy site. The addition of anterior column support is helpful to maintain correction and reduce complications. N/A.

  10. Fast magnetoacoustic wave trains in coronal holes

    Science.gov (United States)

    Pascoe, D. J.; Nakariakov, V. M.; Kupriyanova, E. G.

    2014-08-01

    Context. Rapidly propagating coronal EUV disturbances recently discovered in the solar corona are interpreted in terms of guided fast magnetoacoustic waves. Fast magnetoacoustic waves experience geometric dispersion in waveguides, which causes localised, impulsive perturbations to develop into quasi-periodic wave trains. Aims: We consider the formation of fast wave trains in a super-radially expanding coronal hole modelled by a magnetic funnel with a field-aligned density profile that is rarefied in comparison to the surrounding plasma. This kind of structure is typical of coronal holes, and it forms a fast magnetoacoustic anti-waveguide as a local maximum in the Alfvén speed. Methods: We performed 2D MHD numerical simulations for impulsively generated perturbations to the system. Both sausage and kink perturbations are considered and the role of the density contrast ratio investigated. Results: The anti-waveguide funnel geometry refracts wave energy away from the structure. However, in this geometry the quasi-periodic fast wave trains are found to appear, too, and so can be associated with the observed rapidly propagating coronal EUV disturbances. The wave trains propagate along the external edge of the coronal hole. The fast wave trains generated in coronal holes exhibit less dispersive evolution than in the case of a dense waveguide. Conclusions: We conclude that an impulsive energy release localised in a coronal plasma inhomogeneity develops into a fast wave train for both kink and sausage disturbances and for both waveguide and anti-waveguide transverse plasma profiles.

  11. Observational features of equatorial coronal hole jets

    Directory of Open Access Journals (Sweden)

    G. Nisticò

    2010-03-01

    Full Text Available Collimated ejections of plasma called "coronal hole jets" are commonly observed in polar coronal holes. However, such coronal jets are not only a specific features of polar coronal holes but they can also be found in coronal holes appearing at lower heliographic latitudes. In this paper we present some observations of "equatorial coronal hole jets" made up with data provided by the STEREO/SECCHI instruments during a period comprising March 2007 and December 2007. The jet events are selected by requiring at least some visibility in both COR1 and EUVI instruments. We report 15 jet events, and we discuss their main features. For one event, the uplift velocity has been determined as about 200 km s−1, while the deceleration rate appears to be about 0.11 km s−2, less than solar gravity. The average jet visibility time is about 30 min, consistent with jet observed in polar regions. On the basis of the present dataset, we provisionally conclude that there are not substantial physical differences between polar and equatorial coronal hole jets.

  12. Evolution of the postoperative sagittal spinal profile in early-onset scoliosis: is there a difference between rib-based and spine-based growth-friendly instrumentation?

    Science.gov (United States)

    Chen, Zhonghui; Li, Song; Qiu, Yong; Zhu, Zezhang; Chen, Xi; Xu, Liang; Sun, Xu

    2017-12-01

    OBJECTIVE Although the vertical expandable prosthetic titanium rib (VEPTR) and growing rod instrumentation (GRI) encourage spinal growth via regular lengthening, they can create different results because of their different fixation patterns and mechanisms in correcting scoliosis. Previous studies have focused comparisons on coronal plane deformity with minimal attention to the sagittal profile. In this retrospective study, the authors aimed to compare the evolution of the sagittal spinal profile in early-onset scoliosis (EOS) treated with VEPTR versus GRI. METHODS The data for 11 patients with VEPTR and 22 with GRI were reviewed. All patients had more than 2 years' follow-up with more than 2 lengthening procedures. Radiographic measurements were performed before and after the index surgery and at the latest follow-up. The complications in both groups were recorded. RESULTS Patients in both groups had similar diagnoses, age at the index surgery, and number of lengthening procedures. The changes in the major coronal Cobb angle and T1-S1 spinal height were not significantly different between the 2 groups. Compared with the GRI group, the VEPTR group had less correction in thoracic kyphosis (23% ± 12% vs 44% ± 16%, p < 0.001) after the index surgery and experienced a greater correction loss in thoracic kyphosis (46% ± 18% vs 11% ± 8%, p < 0.001) at the latest follow-up. Although the increase in the proximal junctional angle was not significantly different (VEPTR: 7° ± 4° vs GRI: 8° ± 5°, p = 0.569), the incidence of proximal junctional kyphosis was relatively lower in the VEPTR group (VEPTR: 18.2% vs GRI: 22.7%). No significant changes in the spinopelvic parameters were observed, while the sagittal vertical axis showed a tendency toward a neutral position in both groups. The overall complication rate was higher in the VEPTR group than in the GRI group (72.7% vs 54.5%). CONCLUSIONS The VEPTR had coronal correction and spinal growth results similar to those

  13. Compton backscattering axial spectrometer

    International Nuclear Information System (INIS)

    Rad'ko, V.E.; Mokrushin, A.D.; Razumovskaya, I.V.

    1981-01-01

    Compton gamma backscattering axial spectrometer of new design with the 200 time larger aperture as compared with the known spectrometers at the equal angular resolution (at E=159 keV) is described. Collimator unit, radiation source and gamma detector are located in the central part of the spectrometer. The investigated specimen (of cylindrical form) and the so called ''black body'' used for absorption of photons, passed through the specimen are placed in the peripheric part. Both these parts have an imaginary symmetry axis that is why the spectrometer is called axial. 57 Co is used as the gamma source. The 122 keV spectral line which corresponds to the 83 keV backscattered photon serves as working line. Germanium disk detector of 10 mm diameter and 4 mm height has energy resolution not worse than 900 eV. The analysis of results of test measurements of compton water profile and their comparison with data obtained earlier show that only finity of detector resolution can essentially affect the form of Compton profile. It is concluded that the suggested variant of the spectrometer would be useful for determination of Compton profiles of chemical compounds of heavy elements [ru

  14. Space weather and coronal mass ejections

    CERN Document Server

    Howard, Tim

    2013-01-01

    Space weather has attracted a lot of attention in recent times. Severe space weather can disrupt spacecraft, and on Earth can be the cause of power outages and power station failure. It also presents a radiation hazard for airline passengers and astronauts. These ""magnetic storms"" are most commonly caused by coronal mass ejections, or CMES, which are large eruptions of plasma and magnetic field from the Sun that can reach speeds of several thousand km/s. In this SpringerBrief, Space Weather and Coronal Mass Ejections, author Timothy Howard briefly introduces the coronal mass ejection, its sc

  15. Intra-operative complications in sagittal and vertical ramus osteotomies

    NARCIS (Netherlands)

    van Merkesteyn, J. P.; Groot, R. H.; van Leeuwaarden, R.; Kroon, F. H.

    1987-01-01

    In orthognatic surgery of the mandibular ramus, intra-operative complications as a lesion of the inferior alveolar nerve, fractures of the osteotomised segments, incomplete sectioning, malpositioning of segments and haemorrhage may occur. In this report, intra-operative complications in 124 sagittal

  16. Lenke 1 and 5: changes in sagittal balance

    Directory of Open Access Journals (Sweden)

    Delson Valdemir Pessin

    2014-09-01

    Full Text Available OBJECTIVE: To assess in a cross-sectional study whether there are changes in sagittal balance in patients with adolescent idiopathic scoliosis Lenke types 1 and 5 compared with patients without pathology of the spine and compare the values of the parameters of normal subjects with the parameters found in the literature. METHODS: We measured the values of the parameters of sagittal balance of 21 patients with scoliosis and 14 patients without scoliosis in panoramic radiographs or simply collected data previously measured from the medical records. We compared the mean values of normal subjects, the mean values found in the literature, and the means between normal subjects and patients with scoliosis. For this, we used the Student t test. RESULTS: Using a confidence interval of 5% (p < 0.05 and the Student t test we obtained statistical significance in the comparison of two parameters of sagittal balance between normal subjects and patients with scoliosis. We observed similarities in the measurements of the average parameters of normal subjects with regard to the work already published. CONCLUSIONS: The adolescent idiopathic scoliosis causes changes in two parameters of sagittal balance with statistical significance but suggests changes in all other parameters. As for comparison with previously published work, the results were similar.

  17. Distraction Osteogenesis Technique for the Treatment of Nonsyndromic Sagittal Synostosis

    OpenAIRE

    Johns, Dana; Blagg, Ross; Kestle, John R. W.; Riva-Cambrin, Jay K.; Siddiqi, Faizi; Gociman, Barbu

    2015-01-01

    Background Historically, surgical treatment of children with a delayed presentation of cranial synostosis required complex cranial vault reconstruction. Recently, less invasive options for surgical correction, such as internal distraction osteogenesis, have been explored. In this study, we describe the successful management of delayed presentation of sagittal synostosis using distraction osteogenesis. Methods A bicoronal incision was made and 2 large rectangular osteotomies were performed bil...

  18. Sagittal plane considerations and the pelvis in the adult patient.

    Science.gov (United States)

    Schwab, Frank; Lafage, Virginie; Patel, Ashish; Farcy, Jean-Pierre

    2009-08-01

    Research update, focused review. Identify the role of the pelvis in the setting of adults with spinal deformity. Sagittal plane alignment is increasingly recognized as a critical parameter in the setting of adult spinal deformity. Additionally, pelvic parameters reveal to be a key component in the regulation of sagittal alignment. Analysis of the pelvis in the sagittal plane is commonly assessed by 3 angular measurements: the pelvic incidence (morphologic parameter directly linked to sagittal morphotypes), the pelvic tilt (or pelvis retroversion used to maintain an upright posture in the setting of spinal deformity), and the sacral slope. Recent work using force plate technology has revealed that in the setting of anterior trunk inclination ("spinal imbalance"), the pelvis shifted posteriorly (toward the heels) in order to maintain a balanced mass distribution. The complex relationship between pelvic and spinal parameter were investigated in order to construct predictive formulas of postoperative spinopelvic alignment. It has emerged that pelvic tilt is highly correlated with patient self reported function (ODI, SF-12, and SRS). It has become evident that good clinical outcome in the treatment of spinal deformity requires proper alignment. Pelvis parameters play an essential role not only in terms of spine morphotypes but also in regulating standing balance and postoperative alignment. Thus, optimal treatment of a patient with spinal deformity requires integration of the pelvis in the preoperative evaluation and treatment plan.

  19. A morphological description of the sagittal otoliths of two mormyrids ...

    African Journals Online (AJOL)

    The morphology of the sagittal otoliths of two South African mormyrid fish, Marcusenius macrolepidotus and Petrocephalus catostoma, were studied to determine possible morphological significance. The sagittae of M. macrolepidotus and P. catostoma are kidney-shaped and oblong, respectively. The ventral margin is ...

  20. Use of limited MR protocol (coronal STIR) in the evaluation of patients with hip pain

    International Nuclear Information System (INIS)

    Khoury, N.J.; Birjawi, G.A.; Hourani, M.H.; Chaaya, M.

    2003-01-01

    To assess the role of a limited MR protocol (coronal STIR) as the initial part of the MR examination in patients with hip pain. Eighty-five patients presenting with hip pain, and normal radiographs of the pelvis, and who underwent our full MR protocol for hips were included retrospectively in the study. The full protocol consists of coronal T1-weighted and short tau inversion-recovery (STIR), and axial T2-weighted sequences. Ninety-three MR examinations were performed. Two radiologists interpreted the STIR (limited) examinations and the full studies separately, masked to each other's findings and to the final diagnosis. Comparison between the two protocols was then undertaken. For both readers, all normal MR examinations on the coronal STIR limited protocol were normal on the full protocol, with an interobserver reliability of 0.96. The STIR protocol was able to detect the presence or absence of an abnormality in 100% of cases (sensitivity). The STIR-only protocol provided a specific diagnosis in only 65% of cases (specificity). A normal coronal STIR study of the hips in patients with hip pain and normal radiographs precludes the need for further pelvic MR sequences. Any abnormality detected on this limited protocol should be further assessed by additional MR sequences. (orig.)

  1. Developing a System for Efficient Analysis of Lumbosacral Sagittal Balance

    Directory of Open Access Journals (Sweden)

    D. M. Zhuk

    2015-01-01

    Full Text Available Lumbosacral sagittal balance is the neutral vertical alignment in the sagittal plane to provide decreasing stress loading on muscular-ligamentous structures. The achieving sagittal balance is a basis to provide successful surgical treatment and minimize further complications. As of today, there is no standard quantitative evaluation method of sagittal lumbo-sacral balance, which allows conducting its effective analysis and planning surgical treatment taking into consideration the preservation of normal biomechanics of lumbosacral spine. The goal of the study is to develop a diagnostic system for individual correction of lumbo-sacral sagittal balance by the author’s method with automatic counting and optimized matching of data values based on a specified number of terms using medical visualization data. This study has been conducted with RMAPE’s Department of Traumatology and Orthopedic Surgery. To solve the problem, a random searching algorithm has been exploited. The stop condition of the algorithm was to achieve the objective function value in adjusted interval, initial points of which are the calculated (angular values. The interaction of the angular values, used in the proposed method has been investigated, and their proportional change has been proved. Moreover, the mathematical dependence among geometrical and anatomical parameters of lumbosacral spine has been determined. Based on conducted study, a number of algorithms enabling the automation of the individual determination of optimal lumbosacral balance’s parameters at preoperative planning stage for patients with vertebral column diseases have been created. This allows us to raise physician’s efficiency, minimize mid- and long-term risk of postoperative complications, and avoid reoperations, and prognosticate long-term complications already performed surgery.

  2. Observational Consequences of Coronal Heating Mechanisms

    Science.gov (United States)

    Winebarger, Amy R.; Cirtain, Jonathan C.; Golub, Leon; Kobayashi, Ken

    2014-01-01

    The coronal heating problem remains unsolved today, 80 years after its discovery, despite 50 years of suborbital and orbital coronal observatories. Tens of theoretical coronal heating mechanisms have been suggested, but only a few have been able to be ruled out. In this talk, we will explore the reasons for the slow progress and discuss the measurements that will be needed for potential breakthrough, including imaging the solar corona at small spatial scales, measuring the chromospheric magnetic fields, and detecting the presence of high temperature, low emission measure plasma. We will discuss three sounding rocket instruments developed to make these measurements: the High resolution Resolution Coronal Imager (Hi-C), the Chromospheric Lyman-Alpha Spectropolarimeter (CLASP), and the Marshall Grazing Incidence X-ray Spectrometer (MaGIXS).

  3. Axial skeletal CT densitometry

    International Nuclear Information System (INIS)

    Lampmann, L.E.H.

    1982-01-01

    Since the discovery of the Roentgen ray a precise and accurate assessment of bone mineral content has been a challenge to many investigators. A number of methods have been developed but no one satisfied. Considering its technical possibilities computed tomography is very promising in determination of bone mineral content (BMC). The new modality enables BMC estimations in the axial skeletal trabecular bone. CT densitometry can be performed on a normal commercially available third generation whole body CT scanner. No dedicated device in a special clinical set-up is necessary. In this study 106 patients, most of them clinically suspected of osteoporosis, were examined. The new method CT densitometry has been evaluated. The results have been correlated to alternative BMC determination methods. (Auth.)

  4. Composition of Coronal Mass Ejections

    Science.gov (United States)

    Zurbuchen, T. H.; Weberg, M.; von Steiger, R.; Mewaldt, R. A.; Lepri, S. T.; Antiochos, S. K.

    2016-01-01

    We analyze the physical origin of plasmas that are ejected from the solar corona. To address this issue, we perform a comprehensive analysis of the elemental composition of interplanetary coronal mass ejections (ICMEs) using recently released elemental composition data for Fe, Mg, Si, S, C, N, Ne, and He as compared to O and H. We find that ICMEs exhibit a systematic abundance increase of elements with first ionization potential (FIP) less than 10 electronvolts, as well as a significant increase of Ne as compared to quasi-stationary solar wind. ICME plasmas have a stronger FIP effect than slow wind, which indicates either that an FIP process is active during the ICME ejection or that a different type of solar plasma is injected into ICMEs. The observed FIP fractionation is largest during times when the Fe ionic charge states are elevated above Q (sub Fe) is greater than 12.0. For ICMEs with elevated charge states, the FIP effect is enhanced by 70 percent over that of the slow wind. We argue that the compositionally hot parts of ICMEs are active region loops that do not normally have access to the heliosphere through the processes that give rise to solar wind. We also discuss the implications of this result for solar energetic particles accelerated during solar eruptions and for the origin of the slow wind itself.

  5. Coronal rain in magnetic bipolar weak fields

    Science.gov (United States)

    Xia, C.; Keppens, R.; Fang, X.

    2017-07-01

    Aims: We intend to investigate the underlying physics for the coronal rain phenomenon in a representative bipolar magnetic field, including the formation and the dynamics of coronal rain blobs. Methods: With the MPI-AMRVAC code, we performed three dimensional radiative magnetohydrodynamic (MHD) simulation with strong heating localized on footpoints of magnetic loops after a relaxation to quiet solar atmosphere. Results: Progressive cooling and in-situ condensation starts at the loop top due to radiative thermal instability. The first large-scale condensation on the loop top suffers Rayleigh-Taylor instability and becomes fragmented into smaller blobs. The blobs fall vertically dragging magnetic loops until they reach low-β regions and start to fall along the loops from loop top to loop footpoints. A statistic study of the coronal rain blobs finds that small blobs with masses of less than 1010 g dominate the population. When blobs fall to lower regions along the magnetic loops, they are stretched and develop a non-uniform velocity pattern with an anti-parallel shearing pattern seen to develop along the central axis of the blobs. Synthetic images of simulated coronal rain with Solar Dynamics Observatory Atmospheric Imaging Assembly well resemble real observations presenting dark falling clumps in hot channels and bright rain blobs in a cool channel. We also find density inhomogeneities during a coronal rain "shower", which reflects the observed multi-stranded nature of coronal rain. Movies associated to Figs. 3 and 7 are available at http://www.aanda.org

  6. MULTIDIMENSIONAL MODELING OF CORONAL RAIN DYNAMICS

    International Nuclear Information System (INIS)

    Fang, X.; Xia, C.; Keppens, R.

    2013-01-01

    We present the first multidimensional, magnetohydrodynamic simulations that capture the initial formation and long-term sustainment of the enigmatic coronal rain phenomenon. We demonstrate how thermal instability can induce a spectacular display of in situ forming blob-like condensations which then start their intimate ballet on top of initially linear force-free arcades. Our magnetic arcades host a chromospheric, transition region, and coronal plasma. Following coronal rain dynamics for over 80 minutes of physical time, we collect enough statistics to quantify blob widths, lengths, velocity distributions, and other characteristics which directly match modern observational knowledge. Our virtual coronal rain displays the deformation of blobs into V-shaped features, interactions of blobs due to mostly pressure-mediated levitations, and gives the first views of blobs that evaporate in situ or are siphoned over the apex of the background arcade. Our simulations pave the way for systematic surveys of coronal rain showers in true multidimensional settings to connect parameterized heating prescriptions with rain statistics, ultimately allowing us to quantify the coronal heating input.

  7. MULTIDIMENSIONAL MODELING OF CORONAL RAIN DYNAMICS

    Energy Technology Data Exchange (ETDEWEB)

    Fang, X.; Xia, C.; Keppens, R. [Centre for mathematical Plasma Astrophysics, Department of Mathematics, KU Leuven, B-3001 Leuven (Belgium)

    2013-07-10

    We present the first multidimensional, magnetohydrodynamic simulations that capture the initial formation and long-term sustainment of the enigmatic coronal rain phenomenon. We demonstrate how thermal instability can induce a spectacular display of in situ forming blob-like condensations which then start their intimate ballet on top of initially linear force-free arcades. Our magnetic arcades host a chromospheric, transition region, and coronal plasma. Following coronal rain dynamics for over 80 minutes of physical time, we collect enough statistics to quantify blob widths, lengths, velocity distributions, and other characteristics which directly match modern observational knowledge. Our virtual coronal rain displays the deformation of blobs into V-shaped features, interactions of blobs due to mostly pressure-mediated levitations, and gives the first views of blobs that evaporate in situ or are siphoned over the apex of the background arcade. Our simulations pave the way for systematic surveys of coronal rain showers in true multidimensional settings to connect parameterized heating prescriptions with rain statistics, ultimately allowing us to quantify the coronal heating input.

  8. Improving tibial component coronal alignment during total knee arthroplasty with use of a tibial planing device.

    Science.gov (United States)

    Patil, Shantanu; D'Lima, Darryl D; Fait, James M; Colwell, Clifford W

    2007-02-01

    The outcomes of knee arthroplasty have been shown to be affected by component alignment. Intramedullary and extramedullary alignment instrumentation are fairly effective for achieving the desired mean tibial component coronal alignment. However, there are outliers representing >3 degrees of varus or valgus alignment with respect to the anatomic tibial shaft axis. We measured the efficacy of a custom tibial planing device for reducing the outliers in tibial alignment. We designed a tibial planing tool in an effort to improve tibial alignment. In one cohort (100 knees), we used traditional intramedullary alignment instrumentation to make the tibial bone cut. In a second cohort (120 knees), we used intramedullary alignment instrumentation to make the cut and also used a custom tool to check the cut and to correct an inexact cut. Tibial tray alignment relative to the long axis of the tibial shaft was measured in the coronal and sagittal planes on postoperative radiographs. The target coronal alignment was 90 degrees with respect to the tibial shaft axis (with alignment). A total of 100 anteroposterior radiographs and sixty-five lateral radiographs were analyzed for the group that was treated with traditional instrumentation alone, and a total of 120 anteroposterior radiographs and fifty-five lateral radiographs were analyzed for the group that was treated with use of the custom tibial planing device. The mean coronal alignment of the tibial component was 89.5 degrees +/- 2.1 degrees in the group that was treated with traditional instrumentation alone and 89.6 degrees +/- 1.4 degrees in the group that was treated with use of the custom planing device. Although the mean coronal alignment was not significantly different, the number of outliers was substantially reduced when the custom planing device was used. All 120 components that had been aligned with use of the custom planing device were within 3 degrees of the target coronal alignment, compared with only eighty

  9. Coronal CT scan measurements and hearing evolution in enlarged vestibular aqueduct syndrome.

    Science.gov (United States)

    Saliba, Issam; Gingras-Charland, Marie-Eve; St-Cyr, Karine; Décarie, Jean-Claude

    2012-04-01

    To assess the correlation between the enlarged vestibular aqueduct (EVA) diameter and (1) the hearing loss level (mild, moderate, severe and profound and (2) the hearing evolution. The secondary objective was to obtain measurement limits on the coronal plane of the temporal bone CT scan for the diagnosis of EVA. Retrospective study in a tertiary pediatric center. Mastoid CT scans were reviewed to measure the VA diameter at its midpoint and operculum on axial and coronal planes in a pathologic and normal population. We used their serial audiograms to assess the evolution of hearing. 101 EVA was identified out of 1812 temporal bones CT scan from our radiologic database in 8 years. Bone conduction was stable after a mean follow-up of 40.9 ± 32.9 months. PTA has been the most affected in time by the EVA (p=0.006). No correlation was identified between impedancemetry and the diameter of the EVA. On the diagnostic audiogram, 61% of hearing loss were in the mild and moderate hearing levels; at the end of the follow-up 64% of hearing loss are still in the mild and moderate hearing levels. The cut-off values for the coronal midpoint and operculum planes on the CT scan to diagnose an EVA are 2.4 mm and 4.34 mm respectively. Conductive or mixed hearing loss might be the first manifestation of EVA. Coronal CT scan cuts can provide additional information to evaluate EVA especially when axial cuts are not conclusive. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  10. The addition of a sagittal image fusion improves the prostate cancer detection in a sensor-based MRI /ultrasound fusion guided targeted biopsy.

    Science.gov (United States)

    Günzel, Karsten; Cash, Hannes; Buckendahl, John; Königbauer, Maximilian; Asbach, Patrick; Haas, Matthias; Neymeyer, Jörg; Hinz, Stefan; Miller, Kurt; Kempkensteffen, Carsten

    2017-01-13

    To explore the diagnostic benefit of an additional image fusion of the sagittal plane in addition to the standard axial image fusion, using a sensor-based MRI/US fusion platform. During July 2013 and September 2015, 251 patients with at least one suspicious lesion on mpMRI (rated by PI-RADS) were included into the analysis. All patients underwent MRI/US targeted biopsy (TB) in combination with a 10 core systematic prostate biopsy (SB). All biopsies were performed on a sensor-based fusion system. Group A included 162 men who received TB by an axial MRI/US image fusion. Group B comprised 89 men in whom the TB was performed with an additional sagittal image fusion. The median age in group A was 67 years (IQR 61-72) and in group B 68 years (IQR 60-71). The median PSA level in group A was 8.10 ng/ml (IQR 6.05-14) and in group B 8.59 ng/ml (IQR 5.65-12.32). In group A the proportion of patients with a suspicious digital rectal examination (DRE) (14 vs. 29%, p = 0.007) and the proportion of primary biopsies (33 vs 46%, p = 0.046) were significantly lower. The rate of PI-RADS 3 lesions were overrepresented in group A compared to group B (19 vs. 9%; p = 0.044). Classified according to PI-RADS 3, 4 and 5, the detection rates of TB were 42, 48, 75% in group A and 25, 74, 90% in group B. The rate of PCa with a Gleason score ≥7 missed by TB was 33% (18 cases) in group A and 9% (5 cases) in group B; p-value 0.072. An explorative multivariate binary logistic regression analysis revealed that PI-RADS, a suspicious DRE and performing an additional sagittal image fusion were significant predictors for PCa detection in TB. 9 PCa were only detected by TB with sagittal fusion (sTB) and sTB identified 10 additional clinically significant PCa (Gleason ≥7). Performing an additional sagittal image fusion besides the standard axial fusion appears to improve the accuracy of the sensor-based MRI/US fusion platform.

  11. Dissipative Axial Inflation

    CERN Document Server

    Notari, Alessio

    2016-12-22

    We analyze in detail the background cosmological evolution of a scalar field coupled to a massless abelian gauge field through an axial term $\\frac{\\phi}{f_\\gamma} F \\tilde{F}$, such as in the case of an axion. Gauge fields in this case are known to experience tachyonic growth and therefore can backreact on the background as an effective dissipation into radiation energy density $\\rho_R$, which which can lead to inflation without the need of a flat potential. We analyze the system, for momenta $k$ smaller than the cutoff $f_\\gamma$, including numerically the backreaction. We consider the evolution from a given static initial condition and explicitly show that, if $f_\\gamma$ is smaller than the field excursion $\\phi_0$ by about a factor of at least ${\\cal O} (20)$, there is a friction effect which turns on before that the field can fall down and which can then lead to a very long stage of inflation with a generic potential. In addition we find superimposed oscillations, which would get imprinted on any kind of...

  12. Sagittal Balance in Adolescent Idiopathic Scoliosis: A Radiographic Study of Spinopelvic Compensation After Selective Posterior Fusion of Thoracolumbar/Lumbar (Lenke 5C) Curves.

    Science.gov (United States)

    Xu, Xi-Ming; Wang, Fei; Zhou, Xiao-Yi; Liu, Zi-Xuan; Wei, Xian-Zhao; Bai, Yu-Shu; Li, Ming

    2015-11-01

    The relationship between spinal sagittal alignment and pelvic parameters is well known in adolescent idiopathic scoliosis. However, few studies have reported the sagittal spinopelvic relationship after selective posterior fusion of thoracolumbar/lumbar (TL/L) curves. We evaluated the relationship between spinal sagittal alignment and the pelvis, and analyzed how the pelvic sagittal state is adjusted in Lenke type 5C patients. We conducted a retrospective study of 36 patients with Lenke type 5C curves who received selective posterior TL/L curve fusion. Coronal and spinopelvic sagittal parameters were pre and postoperatively compared. Pearson coefficients were used to analyze the correlation between all spinopelvic sagittal parameters before and after surgery. We also evaluated 3 pelvic morphologies (anteverted, normal, and retroverted) before and after surgery. Preoperatively, the mean pelvic incidence was 46.0°, with a pelvic tilt and sacral slope (SS) of 8.2° and 37.8°, respectively, and 25% (9/36) of patients had an anteverted pelvis, whereas the other 75% had a normal pelvis. Postoperatively, 42% (15/36) of patients had a retroverted pelvis, 53% (19/36) had a normal pelvis, and 2 patients had an anteverted pelvis. Logistic regression analyses yielded 2 factors that were significantly associated with the risk for a postoperative unrecovered anteverted pelvis, including increased lumbar lordosis (LL) (odds ratio [OR] 4.8, P = 0.029) and increased SS (OR 5.6, P = 0.018). Four factors were significantly associated with the risk of a postoperative newly anteverted pelvis, including LL at the final follow-up (OR 6.9, P = 0.009), increased LL (OR 8.9, P = 0.003), LL below fusion (OR 9.4, P = 0.002), and increased SS (OR 11.5, P = 0.001). The pelvic state may be adjusted after selective posterior TL/L curve fusion in Lenke 5C adolescent idiopathic scoliosis patients. It is difficult to improve an anteverted pelvis in patients who have an LL

  13. Sagittal evaluation of usual standing and sitting spinal posture.

    Science.gov (United States)

    Claeys, Kurt; Brumagne, Simon; Deklerck, Jan; Vanderhaeghen, Jacques; Dankaerts, Wim

    2016-04-01

    Postural rehabilitation often plays an important role in the management of non-specific low back pain. While cervical and lumbar correlations have been demonstrated previously, the different role of the pelvis and the thoracic spine for postural control in sitting and standing remains unclear. The aim of this study was to investigate postural correlations between all spinal regions in standing and sitting. Based on digital photographs eight postural angles were analyzed in 99 young healthy persons. Pearson correlations between different postural angles were calculated. In sitting pelvic tilt demonstrated mostly medium correlations with five out of seven other postural angles, compared to three in standing. In standing trunk angle showed five out of seven mostly medium correlations with other regions compared to four out of seven in usual sitting. The low and different correlations suggest a large between-subject variability in sagittal spinal posture, without the existence of any optimal sagittal posture. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Evolution of the axial system in craniates: morphology and function of the perivertebral musculature

    Directory of Open Access Journals (Sweden)

    Schilling Nadja

    2011-02-01

    limb muscle forces as well as gravitational forces. Associated with the evolution of sagittal mobility and a parasagittal limb posture, axial muscles in mammals also stabilize the trunk against sagittal components of extrinsic limb muscle action as well as the inertia of the body's center of mass. Thus, the axial system is central to the static and dynamic control of the body posture in all craniates and, in gnathostomes, additionally provides the foundation for the mechanical work of the appendicular system.

  15. Kelvin-Helmholtz instability in an Alfven resonant layer of a solar coronal loop

    Science.gov (United States)

    Uchimoto, E.; Strauss, H. R.; Lawson, W. S.

    1991-01-01

    A Kelvin-Helmholtz instability has been identified numerically on an azimuthally symmetric Alfven resonant layer in an axially bounded, straight cylindrical coronal loop. The set of equations is solved numerically as an initial value problem. The linear growth rate of this instability is shown to be approximately proportional to the Alfven driving amplitude and inversely proportional to the width of the Alfven resonant layer. It is also shown that the linear growth rate increases linearly with m - 1 up to a certain m, reaches its maximum value for the mode whose half wavelength is comparable to the Alfven resonant layer width, and decreases at higher azimuthal mode number.

  16. Sagittal x-ray beam deviation at asymmetric inclined diffractors

    Czech Academy of Sciences Publication Activity Database

    Korytár, D.; Hrdý, Jaromír; Artemiev, Nikolai; Ferrari, C.; Freund, A.

    2001-01-01

    Roč. 8, - (2001), s. 1136-1139 ISSN 0909-0495 R&D Projects: GA MŠk OK 305; GA MPO PZ-CH/22 Institutional research plan: CEZ:AV0Z1010914 Keywords : x-ray optics * Si(111) W/grooved crystals * inclined diffraction * out-of-diffraction-plane beams * sagittal focusing Subject RIV: BH - Optics, Masers, Lasers Impact factor: 1.519, year: 2001

  17. OBSERVATIONAL SIGNATURES OF CORONAL LOOP HEATING AND COOLING DRIVEN BY FOOTPOINT SHUFFLING

    Energy Technology Data Exchange (ETDEWEB)

    Dahlburg, R. B.; Taylor, B. D. [LCP and FD, Naval Research Laboratory, Washington, DC 20375 (United States); Einaudi, G. [Berkeley Research Associates, Inc., Beltsville, MD 20705 (United States); Ugarte-Urra, I. [College of Science, George Mason University, Fairfax, VA 22030 (United States); Warren, H. P. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States); Rappazzo, A. F. [Advanced Heliophysics, Pasadena, CA 91106 (United States); Velli, M., E-mail: rdahlbur@lcp.nrl.navy.mil [EPSS, UCLA, Los Angeles, CA 90095 (United States)

    2016-01-20

    The evolution of a coronal loop is studied by means of numerical simulations of the fully compressible three-dimensional magnetohydrodynamic equations using the HYPERION code. The footpoints of the loop magnetic field are advected by random motions. As a consequence, the magnetic field in the loop is energized and develops turbulent nonlinear dynamics characterized by the continuous formation and dissipation of field-aligned current sheets: energy is deposited at small scales where heating occurs. Dissipation is nonuniformly distributed so that only a fraction of the coronal mass and volume gets heated at any time. Temperature and density are highly structured at scales that, in the solar corona, remain observationally unresolved: the plasma of our simulated loop is multithermal, where highly dynamical hotter and cooler plasma strands are scattered throughout the loop at sub-observational scales. Numerical simulations of coronal loops of 50,000 km length and axial magnetic field intensities ranging from 0.01 to 0.04 T are presented. To connect these simulations to observations, we use the computed number densities and temperatures to synthesize the intensities expected in emission lines typically observed with the Extreme Ultraviolet Imaging Spectrometer on Hinode. These intensities are used to compute differential emission measure distributions using the Monte Carlo Markov Chain code, which are very similar to those derived from observations of solar active regions. We conclude that coronal heating is found to be strongly intermittent in space and time, with only small portions of the coronal loop being heated: in fact, at any given time, most of the corona is cooling down.

  18. Introduction of hind foot coronal alignment view

    International Nuclear Information System (INIS)

    Moon, Il Bong; Jeon, Ju Seob; Yoon, Kang Cheol; Choi, Nam Kil; Kim, Seung Kook

    2006-01-01

    Accurate clinical evaluation of the alignment of the calcaneus relative to the tibia in the coronal plane is essential in the evaluation and treatment of hind foot pathologic condition. Previously described standard anteroposterior, lateral, and oblique radiographic methods of the foot or ankle do not demonstrate alignment of the tibia relation to the calcaneus in the coronal plane. The purpose of this study was to introduce hind foot coronal alignment view. Both feet were imaged simultaneously on an elevated, radiolucent foot stand equipment. Both feet stood on a radiolucent platform with equal weight on both feet. Both feet are located foot axis longitudinal perpendicular to the platform. Silhouette tracing around both feet are made, and line is then drawn to bisect the silhouette of the second toe and the outline of the heel. The x-ray beam is angled down approximately 15 .deg. to 20 .deg. This image described tibial axis and medial, lateral tuberosity of calcaneus. Calcaneus do not rotated. The view is showed by talotibial joint space. Although computed tomographic and magnetic resonance imaging techniques are capable of demonstrating coronal hind foot alignment, they lack usefulness in most clinical situations because the foot is imaged in a non-weight bearing position. But hind foot coronal alignment view is obtained for evaluating position changing of inversion, eversion of the hind foot and varus, valgus deformity of calcaneus

  19. Introduction of hind foot coronal alignment view

    Energy Technology Data Exchange (ETDEWEB)

    Moon, Il Bong; Jeon, Ju Seob; Yoon, Kang Cheol; Choi, Nam Kil [Chonnam National University Hospital, Gwangju (Korea, Republic of); Kim, Seung Kook [Gwangju Health College, Gwangju (Korea, Republic of)

    2006-12-15

    Accurate clinical evaluation of the alignment of the calcaneus relative to the tibia in the coronal plane is essential in the evaluation and treatment of hind foot pathologic condition. Previously described standard anteroposterior, lateral, and oblique radiographic methods of the foot or ankle do not demonstrate alignment of the tibia relation to the calcaneus in the coronal plane. The purpose of this study was to introduce hind foot coronal alignment view. Both feet were imaged simultaneously on an elevated, radiolucent foot stand equipment. Both feet stood on a radiolucent platform with equal weight on both feet. Both feet are located foot axis longitudinal perpendicular to the platform. Silhouette tracing around both feet are made, and line is then drawn to bisect the silhouette of the second toe and the outline of the heel. The x-ray beam is angled down approximately 15 .deg. to 20 .deg. This image described tibial axis and medial, lateral tuberosity of calcaneus. Calcaneus do not rotated. The view is showed by talotibial joint space. Although computed tomographic and magnetic resonance imaging techniques are capable of demonstrating coronal hind foot alignment, they lack usefulness in most clinical situations because the foot is imaged in a non-weight bearing position. But hind foot coronal alignment view is obtained for evaluating position changing of inversion, eversion of the hind foot and varus, valgus deformity of calcaneus.

  20. Characterization of Multiflux Axial Compressors

    International Nuclear Information System (INIS)

    Brasnarof, Daniel; Kyung Kyu-Hyung; Rivarola, Martin; Gonzalez Jose; Florido, Pablo; Orellano, Pablo; Bergallo, Juan

    2003-01-01

    In the present work the results of analytical models of performance are compared with experimental data acquired in the multi flux axial compressor test facility, built in The Pilcaniyeu Technological Complex for the SIGMA project.We describe the experimental circuit and the data of the dispersion inside the axial compressor obtained using a tracer gas through one of the annular inlets.The attained results can be used to validate the design code for the multi flux axial compressors and SIGMA industrial plant

  1. Free Magnetic Energy and Coronal Heating

    Science.gov (United States)

    Winebarger, Amy; Moore, Ron; Falconer, David

    2012-01-01

    Previous work has shown that the coronal X-ray luminosity of an active region increases roughly in direct proportion to the total photospheric flux of the active region's magnetic field (Fisher et al. 1998). It is also observed, however, that the coronal luminosity of active regions of nearly the same flux content can differ by an order of magnitude. In this presentation, we analyze 10 active regions with roughly the same total magnetic flux. We first determine several coronal properties, such as X-ray luminosity (calculated using Hinode XRT), peak temperature (calculated using Hinode EIS), and total Fe XVIII emission (calculated using SDO AIA). We present the dependence of these properties on a proxy of the free magnetic energy of the active region

  2. DIRECT OBSERVATION OF SOLAR CORONAL MAGNETIC FIELDS BY VECTOR TOMOGRAPHY OF THE CORONAL EMISSION LINE POLARIZATIONS

    International Nuclear Information System (INIS)

    Kramar, M.; Lin, H.; Tomczyk, S.

    2016-01-01

    We present the first direct “observation” of the global-scale, 3D coronal magnetic fields of Carrington Rotation (CR) Cycle 2112 using vector tomographic inversion techniques. The vector tomographic inversion uses measurements of the Fe xiii 10747 Å Hanle effect polarization signals by the Coronal Multichannel Polarimeter (CoMP) and 3D coronal density and temperature derived from scalar tomographic inversion of Solar Terrestrial Relations Observatory (STEREO)/Extreme Ultraviolet Imager (EUVI) coronal emission lines (CELs) intensity images as inputs to derive a coronal magnetic field model that best reproduces the observed polarization signals. While independent verifications of the vector tomography results cannot be performed, we compared the tomography inverted coronal magnetic fields with those constructed by magnetohydrodynamic (MHD) simulations based on observed photospheric magnetic fields of CR 2112 and 2113. We found that the MHD model for CR 2112 is qualitatively consistent with the tomography inverted result for most of the reconstruction domain except for several regions. Particularly, for one of the most noticeable regions, we found that the MHD simulation for CR 2113 predicted a model that more closely resembles the vector tomography inverted magnetic fields. In another case, our tomographic reconstruction predicted an open magnetic field at a region where a coronal hole can be seen directly from a STEREO-B/EUVI image. We discuss the utilities and limitations of the tomographic inversion technique, and present ideas for future developments

  3. Radio emission from coronal and interplanetary shocks

    International Nuclear Information System (INIS)

    Cane, H.V.

    1987-01-01

    Observational data on coronal and interplanetary (IP) type II burst events associated with shock-wave propagation are reviewed, with a focus on the past and potential future contributions of space-based observatories. The evidence presented by Cane (1983 and 1984) in support of the hypothesis that the coronal (metric) and IP (kilometric) bursts are due to different shocks is summarized, and the fast-drift kilometric events seen at the same time as metric type II bursts (and designated shock-accelerated or shock-associated events) are characterized. The need for further observations at 0.5-20 MHz is indicated. 20 references

  4. Prospective comparative study between un-enhanced multidetector ...

    African Journals Online (AJOL)

    Rehab Abdel Rahman El Bakry

    Figure 1. A 45 male patient with left renal colic, (A) axial unenhanced MDCT showing left vesico-ureteral calculus (arrow), (B) Axial prone image, (C & D) unenhanced MDCT with curved multiplanar reformatted coronal and sagittal reconstruction showing the calculus (arrow), (E) Sagittal sonographic image of the left kidney ...

  5. Fluorescence axial nanotomography with plasmonics.

    Science.gov (United States)

    Cade, Nicholas I; Fruhwirth, Gilbert O; Krasavin, Alexey V; Ng, Tony; Richards, David

    2015-01-01

    We present a novel imaging technique with super-resolution axial sensitivity, exploiting the changes in fluorescence lifetime above a plasmonic substrate. Using conventional confocal fluorescence lifetime imaging, we show that it is possible to deliver down to 6 nm axial position sensitivity of fluorophores in whole biological cell imaging. We employ this technique to map the topography of the cellular membrane, and demonstrate its application in an investigation of receptor-mediated endocytosis in carcinoma cells.

  6. The Influence of the Solar Coronal Radiation on Coronal Plasma Structures, I: Determination of the Incident Coronal Radiation

    Science.gov (United States)

    Brown, Gerrard M.; Labrosse, Nicolas

    2018-02-01

    Coronal structures receive radiation not only from the solar disc, but also from the corona. This height-dependent incident radiation plays a crucial role in the excitation and the ionisation of the illuminated plasma. The aim of this article is to present a method for computing the detailed incident radiation coming from the solar corona, which is perceived at a point located at an arbitrary height. The coronal radiation is calculated by integrating the radiation received at a point in the corona over all of the corona visible from this point. The emission from the corona at all wavelengths of interest is computed using atomic data provided by CHIANTI. We obtain the spectrum illuminating points located at varying heights in the corona at wavelengths between 100 and 912 Å when photons can ionise H or He atoms and ions in their ground states. As expected, individual spectral lines will contribute most at the height within the corona where the local temperature is closest to their formation temperature. As there are many spectral lines produced by many ions, the coronal intensity cannot be assumed to vary in the same way at all wavelengths and so must be calculated for each separate height that is to be considered. This code can be used to compute the spectrum from the corona illuminating a point at any given height above the solar surface. This brings a necessary improvement to models where an accurate determination of the excitation and ionisation states of coronal plasma structures is crucial.

  7. A reflection on radiographic cephalometry: the evaluation of sagittal discrepancy.

    Science.gov (United States)

    Duterloo, Herman S

    2014-09-01

    A critical review is presented of the basic properties and applications of cephalometry as a clinical tool with a focus on the evaluation of sagittal discrepancy. Diagnostic cephalometric assessments are subjective and not based on evidence. To assess individual skeletal and/or facial soft tissue form subjectively, selected norms are used. Norms have been developed for various ethnical groups to improve clinical applicability, but subjectivity remains. That subjectivity precludes application of a modern review system, making the present review a personal account. The cephalometric evaluation of sagittal discrepancy finds its historic origin in the Angle classification. Recent publications try to improve accuracy in classifying sagittal discrepancy. It remains unclear in what sense such efforts influence treatment decisions and/or treatment effect. Almost all selected landmarks are located on or dependent upon periosteal/endosteal bone image contours. Their homology is based on circumstantial reasoning and stability over time, which is implicitly assumed. However, implant growth studies and histological investigations show most landmarks to be unstable, as they are involved in displacement and bone remodelling. These landmarks are therefore heterologous when used for individual evaluation of change over time. Notwithstanding the above-indicated limitations, diagnostic cephalometric assessments are clinically useful and help to develop perceptions of balance and harmony and communication between colleagues and patients. There is no evidence-based method to prefer one particular diagnostic method. Landmark location accuracy and geometric issues do not play a decisive role. The subjective characteristic of diagnostic evaluations limits their power to size/shape comparisons. Structural superimposition is the valid biologically evidence-based method to provide advanced insight in individual growth and/or treatment changes and their variations. © 2014 British Orthodontic

  8. Lumbosacral sagittal alignment in association to intervertebral disc diseases.

    Science.gov (United States)

    Habibi, Zohreh; Maleki, Farid; Meybodi, Ali Tayebi; Mahdavi, Ali; Saberi, Hooshang

    2014-12-01

    A cross-sectional case-control study was designed to compare the sagittal alignment of lumbosacral regions in two groups of patients suffering from low back pain, one with intervertebral disc pathologies and one without. To evaluate the correlation between lumbosacral sagittal alignment and disc degeneration. Changes in lumbar lordosis and pelvic parameters in degenerative disc lesions have been assessed in few studies. Overall, patients with discopathy were shown to have lower lumbar lordosis and more vertical sacral profiles. From patients with intractable low back pain undergoing lumbosacral magnetic resonance imaging, 50 subjects with disc degeneration and 50 controls with normal scans were consecutively enrolled. A method was defined with anterior tangent-lines going through anterior bodies of L1 and S1 to measure global lumbosacral angle, incorporating both lumbar lordosis and sacral slope. Global lumbosacral angle using the proposed method and lumbar lordosis using Cobb's method were measured in both groups. Lumbar lordosis based on Cobb's method was lower in group with discopathy (20°-67°; mean, 40.48°±9.89°) than control group (30°-62°; mean, 44.96°±7.68°), although it was not statistically significant. The proposed global lumbosacral angle in subject group (53°-103°; mean, 76.5°±11.018°) was less than control group (52°-101°; mean, 80.18°±9.95°), with the difference being statistically significant (p=0.002). Patients with intervertebral disc lesions seem to have more straightened lumbosacral profiles, but it has not been proven which comes first: disc degeneration or changes in sagittal alignment. Finding an answer to this dilemma demands more comprehensive long-term prospective studies.

  9. Simulating coronal condensation dynamics in 3D

    Science.gov (United States)

    Moschou, S. P.; Keppens, R.; Xia, C.; Fang, X.

    2015-12-01

    We present numerical simulations in 3D settings where coronal rain phenomena take place in a magnetic configuration of a quadrupolar arcade system. Our simulation is a magnetohydrodynamic simulation including anisotropic thermal conduction, optically thin radiative losses, and parametrised heating as main thermodynamical features to construct a realistic arcade configuration from chromospheric to coronal heights. The plasma evaporation from chromospheric and transition region heights eventually causes localised runaway condensation events and we witness the formation of plasma blobs due to thermal instability, that evolve dynamically in the heated arcade part and move gradually downwards due to interchange type dynamics. Unlike earlier 2.5D simulations, in this case there is no large scale prominence formation observed, but a continuous coronal rain develops which shows clear indications of Rayleigh-Taylor or interchange instability, that causes the denser plasma located above the transition region to fall down, as the system moves towards a more stable state. Linear stability analysis is used in the non-linear regime for gaining insight and giving a prediction of the system's evolution. After the plasma blobs descend through interchange, they follow the magnetic field topology more closely in the lower coronal regions, where they are guided by the magnetic dips.

  10. Magnetic Source Regions of Coronal Mass Ejections

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... The majority of flare activity arises in active regions which contain sunspots, while Coronal Mass Ejection (CME) activity can also originate from decaying active regions and even so-called quiet solar regions which contain a filament. Two classes of CME, namely flare-related CME events and CMEs ...

  11. Exercising 'Race' Through the Coronation Physical Training ...

    African Journals Online (AJOL)

    During the last decade of the 19th and first two decades of the 20th century, the Cape Colony education authorities employed an instructional method known as physical training or physical training drill. This investigation expands on two previous studies that explored the Coronation Physical Training Competition ...

  12. Evolving Coronal Holes and Interplanetary Erupting Stream ...

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... Coronal holes and interplanetary disturbances are important aspects of the physics of the Sun and heliosphere. Interplanetary disturbances are identified as an increase in the density turbulence compared with the ambient solar wind. Erupting stream disturbances are transient large-scale structures of ...

  13. Evolving Coronal Holes and Interplanetary Erupting Stream ...

    Indian Academy of Sciences (India)

    Abstract. Coronal holes and interplanetary disturbances are important aspects of the physics of the Sun and heliosphere. Interplanetary distur- bances are identified as an increase in the density turbulence compared with the ambient solar wind. Erupting stream disturbances are transient large-scale structures of enhanced ...

  14. Magnetic Topology of Coronal Hole Linkages

    Science.gov (United States)

    Titov, V. S.; Mikic, Z.; Linker, J. A.; Lionello, R.; Antiochos, S. K.

    2010-01-01

    In recent work, Antiochos and coworkers argued that the boundary between the open and closed field regions on the Sun can be extremely complex with narrow corridors of open ux connecting seemingly disconnected coronal holes from the main polar holes, and that these corridors may be the sources of the slow solar wind. We examine, in detail, the topology of such magnetic configurations using an analytical source surface model that allows for analysis of the eld with arbitrary resolution. Our analysis reveals three important new results: First, a coronal hole boundary can join stably to the separatrix boundary of a parasitic polarity region. Second, a single parasitic polarity region can produce multiple null points in the corona and, more important, separator lines connecting these points. Such topologies are extremely favorable for magnetic reconnection, because it can now occur over the entire length of the separators rather than being con ned to a small region around the nulls. Finally, the coronal holes are not connected by an open- eld corridor of finite width, but instead are linked by a singular line that coincides with the separatrix footprint of the parasitic polarity. We investigate how the topological features described above evolve in response to motion of the parasitic polarity region. The implications of our results for the sources of the slow solar wind and for coronal and heliospheric observations are discussed.

  15. Evolving Coronal Holes and Interplanetary Erupting Stream ...

    Indian Academy of Sciences (India)

    ted their sources on the synoptic maps using Carrington coordinates as circles of about 90. ◦ wide. The positional .... the areas of coronal holes, which did not exist in the synoptic chart of the preceding rotation 1680, but are seen to ... of erupting stream on solar disc. The event numbers 7, 8 and 9 refer to Table 1 of Hewish &.

  16. Mechanisms of Coronal Heating S. R. Verma

    Indian Academy of Sciences (India)

    polarity elements. These processes have been shown convincingly to explain the appearance of X-ray bright points, which however, although important in their own right, make up only a small fraction of the total coronal heating (Priest et al. 2002) ...

  17. Role of Magnetic Carpet in Coronal Heating

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... One of the fundamental questions in solar physics is how the solar corona maintains its high temperature of several million Kelvin above photosphere with a temperature of 6000 K. Observations show that solar coronal heating problem is highly complex with many different facts. It is likely that different ...

  18. Microflares as Possible Sources for Coronal Heating

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... On the other hand, the spectra of microflares showhybrid model of thermal and non-thermal emission, which further supports them as possible sources of coronal heating. Our results based on the analysis show that the energy relapsed by the microflares is good enough for heating of the active corona.

  19. Risk factors affecting somatosensory function after sagittal split osteotomy

    DEFF Research Database (Denmark)

    Thygesen, Torben Henrik; Jensen, Allan Bardow; Helleberg, M

    2008-01-01

    Purpose The aim of this study was to evaluate potential individual and intraoperative risk factors associated with bilateral sagittal split osteotomy (BSSO) and to correlate the findings with postoperative changes in somatosensory function. Patients and Methods A total of 18 men and 29 women (mean...... correlations were noted between preoperative values for somatosensory function and changes in these variables after BSSO. Patients with low sensory thresholds before BSSO experienced more impairment than those patients with higher preoperative sensory thresholds. Conclusion These findings imply...... that somatosensory function after BSSO is dependent on both intraoperative risk factors and preoperative sensation levels....

  20. ANALYSIS AND PLANNING OF HINDFOOT DEFORMITY CORRECTION IN SAGITTAL PLANE

    Directory of Open Access Journals (Sweden)

    L. N. Solomin

    2017-01-01

    Full Text Available Background. The disadvantage of the known methods of analysis and planning of hindfoot deformities in the sagittal plaBackground. Long bone deformity planning is well established. However, there are not well described methods of analysis and planning of hindfoot deformities in the sagittal plane. Such planning is made even more difficult with concomitant deformation of the midfoot and/or ankle contracture or malpositioned arthrodesis. The aim of our study was to develop a universal method of analysis and planning of the calcaneus correction, based on the normally derived reference lines and angles.Methods. We analyzed 65 standing lateral foot films in normal adults, 23-54 years old were analyzed. We drew the talus joint line (points “a” and “b” – Line 1. We drew a second line, (Line 2 the calcaneal line, which starts at the back of the calcaneal tuberosity (point “d”, drawn perpendicular to a line from top to bottom of the calcaneal tuberosity. The intersection of the calcaneal line and the talar joint line form point (c anteriorly. We measured lines ab, ac and cd, and their ratios: ac/ab, and cd/ab.Results. Talar joint line (Line 1 and calcaneal line (Line 2 intersect at a point (c, forming an angle 15.2° (±3.4°. The ratio ac/ab = 2.56 (± 1.1. The ratio cd/ab = 4.59 (±1.0. These ratios are constants for calculating the idealized joint lines for deformity planning. For deformity cases, draw Line 1, the talar joint line ab. Extend that line anteriorly to (c, which is a distance ab×2.56 from point (a. From (c, draw an idealized calcaneal line, Line-2, at an angle 15° to Line 1. Place (d on this line, at a distance ab×4.59 from point (c. Next, draw the deformed calcaneal line (Line 3 and point (d1 where it exits the calcaneal tuberosity. Use the same technique and landmarks as for drawing the normal calcaneal line. The intersection of Lines 2 and 3 is the apex of the deformity. Rotate the piece containing Line 3 around this

  1. Articulator-related registration and analysis of sagittal condylar inclination

    OpenAIRE

    Čimić, Samir; Kraljević Šimunković, Sonja; Simonić Kocijan, Sunčana; Matijević, Jurica; Dulčić, Nikša; Ćatić, Amir

    2015-01-01

    The purpose of this investigation was to study sagittal condylar inclination values within a uniform sample (Angle class I occlusion) using ‘articulator-related registration’ and Camper’s plane as a reference plane. The study was performed on a sample of 58 Angle class I subjects (mean age 25.1, SD 3.1). Measurements were performed with an ultrasonic jaw tracking device with six degrees of freedom. After a paraocclusal tray was fixed in the mouth, each subject had to make three protrusive ...

  2. Diagnosis and evaluation of esophageal atresia by direct sagittal CT

    International Nuclear Information System (INIS)

    Tam, P.K.H.; Saing, H.; Chan, F.L.

    1987-01-01

    Direct sagittal CT is possible in newborns because of their small body-size. With this noninvasive investigation, we were able to establish a correct diagnosis in two neonates with esophageal atresia. Moreover, the demonstration of the air-filled proximal pouch and distal tracheoesophageal fistula along their whole lengths allowed exclusion of the possibility of a proximal pouch fistula and gave knowledge of the exact distance of the two segments of the esophagus needed to be bridged to allow anastomosis, thus providing additional valuable information for the surgeon preoperatively.

  3. Standing sausage modes in curved coronal slabs

    Science.gov (United States)

    Pascoe, D. J.; Nakariakov, V. M.

    2016-09-01

    Context. Magnetohydrodynamic waveguides such as dense coronal loops can support standing modes. The ratios of the periods of oscillations for different longitudinal harmonics depend on the dispersive nature of the waveguide and so may be used as a seismological tool to determine coronal parameters. Aims: We extend models of standing sausage modes in low β coronal loops to include the effects of loop curvature. The behaviour of standing sausage modes in this geometry is used to explain the properties of observed oscillations that cannot be accounted for using straight loop models. Methods: We perform 2D numerical simulations of an oscillating coronal loop, modelled as a dense slab embedded in a potential magnetic field. The loop is field-aligned and so experiences expansion with height in addition to being curved. Standing sausage modes are excited by compressive perturbations of the loop and their properties are studied. Results: The spatial profiles of standing sausage modes are found to be modified by the expanding loop geometry typical for flaring loops and modelled by a potential magnetic field in our simulations. Longitudinal harmonics of order n > 1 have anti-nodes that are shifted towards the loop apex and the amplitude of anti-nodes near the loop apex is smaller than those near the loop footpoints. Conclusions: We find that the observation of standing sausage modes by the Nobeyama Radioheliograph in a flaring coronal loop on 12 January 2000 is consistent with interpretation in terms of the global mode (n = 1) and third harmonic (n = 3). This interpretation accounts for the period ratio and spatial structure of the observed oscillations.

  4. INTERCHANGE RECONNECTION AND CORONAL HOLE DYNAMICS

    International Nuclear Information System (INIS)

    Edmondson, J. K.; Antiochos, S. K.; DeVore, C. R.; Lynch, B. J.; Zurbuchen, T. H.

    2010-01-01

    We investigate the effect of magnetic reconnection between open and closed fields, often referred to as 'interchange' reconnection, on the dynamics and topology of coronal hole boundaries. The most important and most prevalent three-dimensional topology of the interchange process is that of a small-scale bipolar magnetic field interacting with a large-scale background field. We determine the evolution of such a magnetic topology by numerical solution of the fully three-dimensional MHD equations in spherical coordinates. First, we calculate the evolution of a small-scale bipole that initially is completely inside an open field region and then is driven across a coronal hole boundary by photospheric motions. Next the reverse situation is calculated in which the bipole is initially inside the closed region and driven toward the coronal hole boundary. In both cases, we find that the stress imparted by the photospheric motions results in deformation of the separatrix surface between the closed field of the bipole and the background field, leading to rapid current sheet formation and to efficient reconnection. When the bipole is inside the open field region, the reconnection is of the interchange type in that it exchanges open and closed fields. We examine, in detail, the topology of the field as the bipole moves across the coronal hole boundary and find that the field remains well connected throughout this process. Our results, therefore, provide essential support for the quasi-steady models of the open field, because in these models the open and closed flux are assumed to remain topologically distinct as the photosphere evolves. Our results also support the uniqueness hypothesis for open field regions as postulated by Antiochos et al. On the other hand, the results argue against models in which open flux is assumed to diffusively penetrate deeply inside the closed field region under a helmet streamer. We discuss the implications of this work for coronal observations.

  5. Does Andrews facial analysis predict esthetic sagittal maxillary position?

    Science.gov (United States)

    Resnick, Cory M; Daniels, Kimberly M; Vlahos, Maryann

    2018-04-01

    Cephalometric analyses have limited utility in planning maxillary sagittal position for orthognathic surgery. In Six Elements of Orofacial Harmony, Andrews quantified maxillary position relative to forehead projection and angulation and proposed an ideal relationship. The purpose of this study was to investigate the ability of this technique to predict esthetic sagittal maxillary position. Survey study including a male and female with straight facial profiles, normal maxillary incisor angulations, and Angle's Class I. Maxillary position was modified on lateral photographs to create 5 images for each participant with incisor-goal anterior limit line (GALL) distances of -4, -2, 0, +2, and +4 mm. A series of health care professionals and laypeople were asked to rate each photo in order of attractiveness. A total of 100 complete responses were received. Incisor-GALL distances of +4 mm (41%) and +2 mm (40%) were most commonly considered "most esthetic" for the female volunteer (P < .001). For the male volunteer, there were 2 peak "most esthetic" responses: incisor-GALL distances of 0 mm (37%) and -4 mm (32%) (P < .001). Respondents considered maxillary incisor position 2 to 4 mm anterior to GALL most attractive in a woman and 0 to 4 mm posterior to GALL most esthetic in a man. Using these modified target distances, this analysis may be useful for orthognathic surgery planning. Copyright © 2018 Elsevier Inc. All rights reserved.

  6. Vertebral artery loop formation depicted on oblique sagittal MR imaging: A case report

    Energy Technology Data Exchange (ETDEWEB)

    Bang, Sun Woo; Han, Kyung Ream; Lee, Mi Kyung; Kim, Hyung Nam; Han, Jae Il; Park, Mi Na; Kim, Chan [Kim Chan Hospital, Suwon (Korea, Republic of)

    2015-02-15

    Vertebral artery loop formation is an anatomic variation that possibly causes cervical nerve root compression, leading to cervical radiculopathy. A few cases of vertebral artery loop formation depicted with conventional sagittal magnetic resonance imaging (MRI) have been reported, but cases of vertebral artery loop formation depicted with oblique sagittal MRI have been less frequently reported. We present a case of vertebral artery loop formation depicted on oblique sagittal MRI.

  7. Vertebral artery loop formation depicted on oblique sagittal MR imaging: A case report

    International Nuclear Information System (INIS)

    Bang, Sun Woo; Han, Kyung Ream; Lee, Mi Kyung; Kim, Hyung Nam; Han, Jae Il; Park, Mi Na; Kim, Chan

    2015-01-01

    Vertebral artery loop formation is an anatomic variation that possibly causes cervical nerve root compression, leading to cervical radiculopathy. A few cases of vertebral artery loop formation depicted with conventional sagittal magnetic resonance imaging (MRI) have been reported, but cases of vertebral artery loop formation depicted with oblique sagittal MRI have been less frequently reported. We present a case of vertebral artery loop formation depicted on oblique sagittal MRI.

  8. Subjective and objective image qualities: a comparison of sagittal T2 weighted spin-echo and turbo-spin-eco sequences in magnetic resonance imaging of the spine by use of a subjective ranking system

    Energy Technology Data Exchange (ETDEWEB)

    Goerres, G. [Institut fuer diagnostische Radiologie, Departement Radiologie, Universitaetskliniken, Kantonsspital Basel (Switzerland); Mader, I. [Radiologische Gemeinschaftspraxis Dres. Siems, Grossmann, Bayreuth (Germany); Proske, M. [Klinikum Rosenheim (Germany). Inst. fuer Diagnostische Radiologie

    1998-12-31

    We evaluated the subjective image impression of two different magnetic resonance (MR) sequences by using a subjective ranking system. This ranking system was based on 20 criteria describing several tissue characteristics such as the signal intensity of normal anatomical structures and the changes of signal intensities and shape of lesions as well as artefacts. MR of the vertebral spine was performed in 48 female and 52 male patients (mean age 44.8 years) referred consecutively for investigation of a back problem. Ninety-six pathologies were found in 82 patients. Sagittal and axial T1 weighted spin-echo before and after administration of Gadolinium (Gd-DOTA), and sagittal T2 weighted spin-echo (T2wSE) and Turbo-spin-echo (TSE) sequences were performed by means of surface coils. Using the subjective ranking system the sagittal T2wSE and sagittal TSE were compared. Both sequences were suitable for identification of normal anatomy and pathologic changes and there was no trend for increased detection of disease by one imaging sequence over the other. We found that sagittal TSE sequences can replace sagittal T2wSE sequences in spinal MR and that artefacts at the cervical and lumbar spine are less frequent using TSE, thus confirming previous studies. In this study, our ranking system reveiled, that there are differences between the subjective judgement of image qualities and objective measurement of SNR. However, this approach may not be helpful to compare two different MR sequences as it is limited to the anatomical area investigated and is time consuming. The subjective image impression, i.e. the quality of images, may not always be represented by physical parameters such as a signal-to-noise ratio (SNR), radiologists should try to define influences of image quality also by subjective parameters. (orig.)

  9. Solar Coronal Jets: Observations, Theory, and Modeling

    Science.gov (United States)

    Raouafi, N. E.; Patsourakos, S.; Pariat, E.; Young, P. R.; Sterling, A.; Savcheva, A.; Shimojo, M.; Moreno-Insertis, F.; Devore, C. R.; Archontis, V.; hide

    2016-01-01

    Chromospheric and coronal jets represent important manifestations of ubiquitous solar transients, which may be the source of signicant mass and energy input to the upper solar atmosphere and the solar wind. While the energy involved in a jet-like event is smaller than that of nominal solar ares and Coronal Mass Ejections (CMEs), jets share many common properties with these major phenomena, in particular, the explosive magnetically driven dynamics. Studies of jets could, therefore, provide critical insight for understanding the larger, more complex drivers of the solar activity. On the other side of the size-spectrum, the study of jets could also supply important clues on the physics of transients closeor at the limit of the current spatial resolution such as spicules. Furthermore, jet phenomena may hint to basic process for heating the corona and accelerating the solar wind; consequently their study gives us the opportunity to attack a broadrange of solar-heliospheric problems.

  10. Axial structure of the nucleon

    Energy Technology Data Exchange (ETDEWEB)

    Veronique Bernard; Latifa Elouadrhiri; Ulf-G Meissner

    2002-01-01

    We review the current status of experimental and theoretical understanding of the axial nucleon structure at low and moderate energies. Topics considered include (quasi)elastic (anti)neutrino-nucleon scattering, charged pion electroproduction off nucleons and ordinary as well as radiative muon capture on the proton.

  11. Axial stability of Taylor bubbles

    NARCIS (Netherlands)

    Lu, X.; Prosperetti, Andrea

    2006-01-01

    Long gas bubbles rising in a vertical tube are observed to lose axial symmetry and become unstable in a downward liquid flow. In this paper an approximate linear stability analysis of this phenomenon is presented. It is found that, under the combined effect of gravity and the pressure gradient which

  12. Supra-acetabular line is better than supra-iliac line for coronal balance referencing-a study of perioperative whole spine X-rays in degenerative lumbar scoliosis and ankylosing spondylitis patients.

    Science.gov (United States)

    Hey, Hwee Weng Dennis; Kim, Cheung-Kue; Lee, Won-Gyu; Juh, Hyung-Suk; Kim, Ki-Tack

    2017-12-01

    The aim of spinal deformity correction is to restore the spine's functional alignment by balancing it in both the sagittal and coronal planes. Regardless of posture, the ideal coronal profile is straight, and therefore readily assessable. This study compares two radiological methods to determine which better predicts postoperative standing coronal balance. We conducted a single-center, radiographic comparative study between 2011 and 2015. A total of 199 patients with a mean age of 55.1 years were studied. Ninety patients with degenerative lumbar scoliosis (DLS) and 109 ankylosing spondylitis (AS) were treated with posterior surgery during this period. Baseline clinical and radiographic parameters (sagittal and coronal) were recorded. Comparison was performed between the new supra-acetabular line (central sacral vertical line [CSVL1]) and conventional supra-iliac line (CSVL2) perpendicular methods of coronal balance assessment. These methods were also compared with the gold standard standing C7 plumb line. Each patient underwent standardized operative procedures and had perioperative spine X-rays obtained for assessment of spinal balance. Adjusted multivariate analysis was used to determine predictors of coronal balance. Significant differences in baseline characteristics (age, gender, and radiographic parameters) were found between patients with DLS and AS. CSVL1, CSVL2, and C7 plumb line differed in all the perioperative measurements. These three radiological methods showed a mean right coronal imbalance for both diagnoses in all pre-, intra-, and postoperative radiographs. The magnitude of imbalance was the greatest for CSVL2 followed by CSVL1 and subsequently the C7 plumb line. A larger discrepancy between CSVL and C7 plumb line measurements intraoperatively than those postoperatively suggests a postural effect on these parameters, which is greater for CSVL2. Multivariate analysis identified that in DLS, the preoperative C7 plumb line was predictive of its

  13. A SURVEY OF CORONAL CAVITY DENSITY PROFILES

    International Nuclear Information System (INIS)

    Fuller, J.; Gibson, S. E.

    2009-01-01

    Coronal cavities are common features of the solar corona that appear as darkened regions at the base of coronal helmet streamers in coronagraph images. Their darkened appearance indicates that they are regions of lowered density embedded within the comparatively higher density helmet streamer. Despite interfering projection effects of the surrounding helmet streamer (which we refer to as the cavity rim), Fuller et al. have shown that under certain conditions it is possible to use a Van de Hulst inversion of white-light polarized brightness (pB) data to calculate the electron density of both the cavity and cavity rim plasma. In this article, we apply minor modifications to the methods of Fuller et al. in order to improve the accuracy and versatility of the inversion process, and use the new methods to calculate density profiles for both the cavity and cavity rim in 24 cavity systems. We also examine trends in cavity morphology and how departures from the model geometry affect our density calculations. The density calculations reveal that in all 24 cases the cavity plasma has a flatter density profile than the plasma of the cavity rim, meaning that the cavity has a larger density depletion at low altitudes than it does at high altitudes. We find that the mean cavity density is over four times greater than that of a coronal hole at an altitude of 1.2 R sun and that every cavity in the sample is over twice as dense as a coronal hole at this altitude. Furthermore, we find that different cavity systems near solar maximum span a greater range in density at 1.2 R sun than do cavity systems near solar minimum, with a slight trend toward higher densities for systems nearer to solar maximum. Finally, we found no significant correlation of cavity density properties with cavity height-indeed, cavities show remarkably similar density depletions-except for the two smallest cavities that show significantly greater depletion.

  14. Plasma Diagnostics of Coronal Dimming Events

    Science.gov (United States)

    Vanninathan, Kamalam; Veronig, Astrid M.; Dissauer, Karin; Temmer, Manuela

    2018-04-01

    Coronal mass ejections are often associated with coronal dimmings, i.e., transient dark regions that are most distinctly observed in Extreme Ultra-violet wavelengths. Using Atmospheric Imaging Assembly (AIA) data, we apply Differential Emission Measure diagnostics to study the plasma characteristics of six coronal dimming events. In the core dimming region, we find a steep and impulsive decrease of density with values up to 50%–70%. Five of the events also reveal an associated drop in temperature of 5%–25%. The secondary dimming regions also show a distinct decrease in density, but less strong, decreasing by 10%–45%. In both the core and the secondary dimming the density changes are much larger than the temperature changes, confirming that the dimming regions are mainly caused by plasma evacuation. In the core dimming, the plasma density reduces rapidly within the first 20–30 minutes after the flare start and does not recover for at least 10 hr later, whereas the secondary dimming tends to be more gradual and starts to replenish after 1–2 hr. The pre-event temperatures are higher in the core dimming (1.7–2.6 MK) than in the secondary dimming regions (1.6–2.0 MK). Both core and secondary dimmings are best observed in the AIA 211 and 193 Å filters. These findings suggest that the core dimming corresponds to the footpoints of the erupting flux rope rooted in the AR, while the secondary dimming represents plasma from overlying coronal structures that expand during the CME eruption.

  15. Fracture mechanism of coronal teenage dentin

    Science.gov (United States)

    Panfilov, P. E.; Kabanova, A. V.; Borodin, I. N.; Guo, J.; Zang, Z.

    2017-10-01

    The structure of coronal teenage dentin and the development of cracks in it are studied on microand nanolevels. The material is found to fail according to a ductile mechanism on a microlelvel and according to a ductile-brittle mechanism on a nanoscale. This behavior is similar to the failure of a polyethylene film and rubber, when significant elastic and irreversible deformation precedes crack growth. The viscoelastic behavior can be considered as the reaction of dentin to an applied mechanical load.

  16. [Development of electroforming apparatus for coronal restoration].

    Science.gov (United States)

    Watanabe, M; Sawada, T; Ukiya, M

    1989-03-01

    As dental technologies become highly developed, techniques have been more diversified. From as aspect of prosthodontic practice, both esthetic and functional requirements are emphasized for coronal restoration and consequently, these should be considered in the routine procedure. In fabrication of coronal restorations, metal, porcelain and resin are commonly used, and there exists the various disadvantages for metal cast method due to complicated processes by using different dental materials. Therefore, an electroforming apparatus was developed by us to replace the conventional procedure by a cathode rotary system. It was applied for coronal restorations to allow an electroforming directly on a working model. An experiment was successfully conducted to apply for a veneer crown on abutment tooth of upper central incisor on plaster model. The results were obtained as follows, 1. It was become possible to construct a metal framework by the electroforming. 2. Metal framework can be constructed on the same working model without a duplication of it. 3. The combined system for cathode rotation and liquid circulation could shorten the electroposition time, and allows a high current density extending to 50 A/dm2.

  17. Coronal Heating Observed with Hi-C

    Science.gov (United States)

    Winebarger, Amy R.

    2013-01-01

    The recent launch of the High-Resolution Coronal Imager (Hi-C) as a sounding rocket has offered a new, different view of the Sun. With approx 0.3" resolution and 5 second cadence, Hi-C reveals dynamic, small-scale structure within a complicated active region, including coronal braiding, reconnection regions, Alfven waves, and flows along active region fans. By combining the Hi-C data with other available data, we have compiled a rich data set that can be used to address many outstanding questions in solar physics. Though the Hi-C rocket flight was short (only 5 minutes), the added insight of the small-scale structure gained from the Hi-C data allows us to look at this active region and other active regions with new understanding. In this talk, I will review the first results from the Hi-C sounding rocket and discuss the impact of these results on the coronal heating problem.

  18. Fast Waves in Smooth Coronal Slab

    Science.gov (United States)

    Lopin, I.; Nagorny, I.

    2015-03-01

    This work investigates the effect of transverse density structuring in coronal slab-like waveguides on the properties of fast waves. We generalized previous results obtained for the exponential and Epstein profiles to the case of an arbitrary transverse density distribution. The criteria are given to determine the possible (trapped or leaky) wave regime, depending on the type of density profile function. In particular, there are plasma slabs with transverse density structuring that support pure trapped fast waves for all wavelengths. Their phase speed is nearly equal to the external Alfvén speed for the typical parameters of coronal loops. Our findings are obtained on the basis of Kneser’s oscillation theorem. To confirm the results, we analytically solved the wave equation evaluated at the cutoff point and the original wave equation for particular cases of transverse density distribution. We also used the WKB method and obtained approximate solutions of the wave equation at the cutoff point for an arbitrary transverse density profile. The analytic results were supplemented by numerical solutions of the obtained dispersion relations. The observed high-quality quasi-periodic pulsations of flaring loops are interpreted in terms of the trapped fundamental fast-sausage mode in a slab-like coronal waveguide.

  19. On the plasma outflow in coronal rays

    International Nuclear Information System (INIS)

    Badalyan, O.G.; Livshits, M.A.

    1989-01-01

    The data set of ground-based and space white-light observations of large coronal rays at the distances (4-25)R sun is discussed. The observed intensities agree with those calculated for a cylindrical structure with a hydrostatic density distribution by the coronal plasma parameters T=1.6x10 6 K and n 0 =81-2)x10 9 cm -3 for different coronal rays. At (5-10) R sun , the observed brightness of concrete streamers apparently decreases with the distance faster than in the hydrostatic model. Since the hydrostatic hypothesis is besides that physically unrealistic in the corona external layers a model with Parker's type plasma outflow in a weakly diverging structure is considered. A concrete model with a singular point r c =7.6 R sun and v (25 R sun )=300 kmxs -1 is chosen which satisfies the observed brightness and contrast of the rays. The streamer flux nv turns out to be large

  20. Temperature Structure of a Coronal Cavity

    Science.gov (United States)

    Kucera, T. A.; Gibson, S. E.; Schmit, D. J.

    2011-01-01

    we analyze the temperature structure of a coronal cavity observed in Aug. 2007. coronal cavities are long, low-density structures located over filament neutral lines and are often seen as dark elliptical features at the solar limb in white light, EUV and x-rays. when these structures erupt they form the cavity portions of CMEs. It is important to establish the temperature structure of cavities in order to understand the thermodynamics of cavities in relation to their three-dimensional magnetic structure. To analyze the temperature we compare temperature ratios of a series of iron lines observed by the Hinode/EUv Imaging spectrometer (EIS). We also use those lines to constrain a forward model of the emission from the cavity and streamer. The model assumes a coronal streamer with a tunnel-like cavity with elliptical cross-section and a Gaussian variation of height along the tunnel lenth. Temperature and density can be varied as a function of altitude both in the cavity and streamer. The general cavity morphology and the cavity and streamer density have already been modeled using data from STEREO's SECCHI/EUVI and Hinode/EIS (Gibson et al 2010 and Schmit & Gibson 2011).

  1. Forward Modeling of a Coronal Cavity

    Science.gov (United States)

    Kucera, T. A.; Gibson, S. E.; Schmit, D. J.

    2011-01-01

    We apply a forward model of emission from a coronal cavity in an effort to determine the temperature and density distribution in the cavity. Coronal cavities are long, low-density structures located over filament neutral lines and are often seen as dark elliptical features at the solar limb in white light, EUV and X-rays. When these structures erupt they form the cavity portions of CMEs The model consists of a coronal streamer model with a tunnel-like cavity with elliptical cross-section and a Gaussian variation of height along the tunnel length. Temperature and density can be varied as a function of altitude both in the cavity and streamer. We apply this model to a cavity observed in Aug. 2007 by a wide array of instruments including Hinode/EIS, STEREO/EUVI and SOHO/EIT. Studies such as these will ultimately help us understand the the original structures which erupt to become CMEs and ICMES, one of the prime Solar Orbiter objectives.

  2. Earth-Affecting Coronal Mass Ejections Without Obvious Low Coronal Signatures

    Science.gov (United States)

    Nitta, N.; Mulligan Skov, T.

    2017-12-01

    We present a study of the origins of coronal mass ejections (CMEs) that were not accompanied by obvious low coronal signatures (LCSs) and yet were responsible for appreciable disturbances at 1 AU. These CMEs characteristically start slowly. In several examples, EUV images taken by the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory reveal coronal dimming and a post-eruption arcade when we make difference images with long enough temporal separations, which are commensurate with the slow initial development of the CME. Data from the EUV imager and COR coronagraphs of the Sun Earth Connection Coronal and Heliospheric Investigation on the Solar Terrestrial Relations Observatory, which provide the limb views of Earth-bound CMEs, greatly help us limit the time interval in which the CME forms and undergoes initial acceleration. For other CMEs, we find similar dimming, although only with lower confidence as to its link to the CME. It is noted that even these unclear events result in unambiguous flux rope signatures in in situ data at 1 AU. There is a tendency that the CME source regions are located near coronal holes or open field regions. This may have implications for both the initiation of the stealthy CME in the corona and its outcome in the heliosphere.

  3. Sagittal spinopelvic parameters in 2-level lumbar degenerative spondylolisthesis

    Science.gov (United States)

    Wang, Tao; Wang, Hui; Liu, Huan; Ma, Lei; Liu, Feng-Yu; Ding, Wen-Yuan

    2016-01-01

    Abstract The purpose of our study is to evaluate sagittal parameters in 2-level lumbar degenerative spondylolisthesis (DS) (TLDS). A total of 15 patients with TLDS, 40 patients with single-level DS (SLDS), and 30 normal volunteers as control were included in our study. All subjects performed on full spine X-ray. Two categorized data were analyzed: patient characteristics—age, sex, body mass index, radiographic parameters-pelvic incidence (PI), pelvic tilt (PT), lumbar lordosis (LL), sacral slope (SS), PI–LL, Cobb between the fifth thoracic vertebral and 12th thoracic vertebral (T5–T12), sagittal vertical axis (SVA) Cobb angle of spondylolisthesis level (CSL), ratio of PT to SS (PT/SS), CSL/LL, variation trend of SS over PI, and LL over PI. The PI (73.1° vs 52.9°), SS (50.8° vs 32.2°), LL (53.1° vs 46.9°), SVA (66.1 vs 22.0 mm), PI–LL (20.0° vs 6.0°), and CSL (23.6° vs 20.0°) in TLDS were significantly larger than these in SLDS. The PI (73.1° vs 40.6°), PT (22.3° vs 17.1°), SS (50.8° vs 23.5°), LL (53.1° vs 32.5°), PI–LL (20.0° vs 8.1°), and SVA (66.1 vs 17.0 mm) in TLDS were significantly larger than those in the normal group (NG). The PI (52.9° vs 40.6°), PT (21.0° vs 17.1°), SS (32.2° vs 23.5°), LL (46.9° vs 32.5°), and SVA (22.0 vs 17.0 mm) in SLDS were significantly higher than those in NG. However, PT/SS (44.0%), LL over PI (y = 0.39x + 24.25), SS over PI (y = 10.79 + 0.55x) were lower in TLDS than these in SLDS (63.8%, y = 0.41x + 25, y = 0.65x − 2.09, respectively), and the similar tend between SLDS and NG (74.0%, y = 0.49x + 13.09, y = 0.67x − 3.9, respectively). Our results showed that 2-level lumbar DS, which was caused by multiple-factors, has a severe sagittal imbalance, but single-level has not any. When we plan for surgical selection for 2-level lumbar DS, global sagittal balance must be considered. PMID:27977581

  4. Assessment of spring cranioplasty biomechanics in sagittal craniosynostosis patients.

    Science.gov (United States)

    Borghi, Alessandro; Schievano, Silvia; Rodriguez Florez, Naiara; McNicholas, Roisin; Rodgers, Will; Ponniah, Allan; James, Greg; Hayward, Richard; Dunaway, David; Jeelani, N U Owase

    2017-11-01

    OBJECTIVE Scaphocephaly secondary to sagittal craniosynostosis has been treated in recent years with spring-assisted cranioplasty, an innovative approach that leverages the use of metallic spring distractors to reshape the patient skull. In this study, a population of patients who had undergone spring cranioplasty for the correction of scaphocephaly at the Great Ormond Street Hospital for Children was retrospectively analyzed to systematically assess spring biomechanical performance and kinematics in relation to spring model, patient age, and outcomes over time. METHODS Data from 60 patients (49 males, mean age at surgery 5.2 ± 0.9 months) who had received 2 springs for the treatment of isolated sagittal craniosynostosis were analyzed. The opening distance of the springs at the time of insertion and removal was retrieved from the surgical notes and, during the implantation period, from planar radiographs obtained at 1 day postoperatively and at the 3-week follow-up. The force exerted by the spring to the patient skull at each time point was derived after mechanical testing of each spring model-3 devices with the same geometry but different wire thicknesses. Changes in the cephalic index between preoperatively and the 3-week follow-up were recorded. RESULTS Stiffer springs were implanted in older patients (p springs were used (p spring models, however, the devices all plateaued. Indeed, regardless of patient age or spring model, after 10 days from insertion, all the devices were open. CONCLUSIONS Results in this study provide biomechanical insights into spring-assisted cranioplasty and could help to improve spring design and follow-up strategy in the future.

  5. Strategic Considerations for Effective Sagittal Resection of the Mandible to Achieve a Slim and Attractive Jawline.

    Science.gov (United States)

    Park, Sanghoon; Lee, Tae Sung

    2018-01-01

    Sagittal resection of the mandible has been widely used to reduce the width of the lower face and is usually carried out in combination with a mandibular contouring procedure. However, the surgical outcomes of this procedure are unclear because sagittal resection is rarely performed as a single procedure. The authors clarify misunderstandings regarding this procedure and introduce an improved strategic approach for sagittal resection of the mandible. Under general anesthesia, mandible contouring was performed first with a curved osteotomy, followed by sagittal resection of the outer cortex of mandible. The amount and extent of each procedure was determined in accordance with preoperative analysis. From 2012 to 2014, a consecutive series of 212 patients who underwent mandible contouring surgery without concomitant chin surgery were included in the study. A total of 189 patients underwent both mandibular contouring surgery and sagittal resection, whereas 13 underwent only sagittal resection and 10 underwent only mandibular contouring surgery. All operations were carried out successfully without any severe complications, and most patients had satisfactory aesthetic outcomes. The authors found that the sagittal resection of the mandible should be performed in accordance with the shape of the mandible to effectively reduce facial width and achieve better aesthetic outcomes for both profile and frontal views. In an outcurved-type mandible, conventional mandibular contouring may be effective alone, whereas sagittal resection focusing on removing the mandible body region is essential for incurved-type mandibles. In straight line-type mandibles, both procedures are necessary. Therapeutic, IV.

  6. Extensor Tendon Instability Due to Sagittal Band Injury in a Martial Arts Athlete: A Case Report.

    Science.gov (United States)

    Kochevar, Andrew; Rayan, Ghazi

    2017-03-01

    A Taekwondo participant sustained a hand injury from punching an opponent that resulted in painful instability of the ring finger extensor digitorum communis tendon due to sagittal band damage. His symptoms resolved after reconstructive surgery on the sagittal band (SB) with stabilization of the extensor tendon over the metacarpophalangeal joint.

  7. Sagittal synostosis: II. Cranial morphology and growth after the modified pi-plasty

    DEFF Research Database (Denmark)

    Guimaraes-Ferreira, J.; Gewalli, F.; David, L.

    2006-01-01

    The aim of this study was to characterise the postoperative cranial growth and morphology after a modified pi-plasty for sagittal synostosis. The shape of the skull of 82 patients with isolated premature synostosis of the sagittal suture ( SS group) operated on with a modified pi-plasty was studi...

  8. [Cephalometric analysis of the relationship between occlusal plane and sagittal position of the mandible].

    Science.gov (United States)

    Ye, Rui; Wang, Sheng; Pei, Jiao; Zhao, Meiying

    2012-12-01

    To investigate the relationship between occlusal plane and sagittal position of the mandible by examining dental and skeletal morphologies of average angle patients for better understanding of etiologies and definitive clinical guidelines of mandibular malpositions. The lateral cephalograms of 114 female average angle patients with neutral maxillary positions were selected and divided into three groups according to sagittal mandibular positions (ANB angle). Twenty-five skeletal and dental measurements were compared. The correlations between skeletal and dental measurements were analyzed by rectilinear correlation. Cant of posterior occlusal plane (OP-P) and height of the upper second molar were significantly related to sagittal position of the mandible (P occlusal plane and sagittal position of the mandible in average angle patients, consistent with the dental morphologies of different skeletal configurations. In treating malocclusions of sagittal discrepancy of mandible, the height of posterior teeth and cant of OP-P might be a primary concern.

  9. The sagittal pelvic tilt index as a criterion in the evaluation of spondylolisthesis. Preliminary observations.

    Science.gov (United States)

    Schwab, F J; Farcy, J P; Roye, D P

    1997-07-15

    Radiographic analysis of a pediatric population with spondylolisthesis was performed to examine sagittal plane pelvic rotation and degree of slip over time. To determine whether the degree of standing sagittal offset of L5 with respect to the acetabulum correlated with slip progression and symptoms. The natural history of isthmic spondylolisthesis remains unclear. Attempts to predict slip progression in the clinical setting, and thus the possible need for eventual surgical intervention, remain imprecise. Predicting slip progression based on sagittal alignment of the L5 vertebra with respect to the acetabulum has been proposed by some investigators. Fifty-two children and adolescents were followed clinically and radiographically for an average of 5.6 years. Serial lateral standing radiographs that included the hips and lumbar spine were measured to compute a sagittal pelvic tilt index. The latter value is a ratio of relative distances from the center of S2 to the projection of L5 and the center of the femoral heads on the horizontal. Of the 52 patients studied, 38 have remained asymptomatic without significant slip progression or change in sagittal pelvic tilt index ratio. Of the original group, 13 patients had significant symptoms and revealed a decrease in the sagittal pelvic tilt index over time. Eight of the 13 stabilized at the end of adolescence, whereas 5 had continued decrease in the sagittal pelvic tilt index ratio. These five required operative treatment for pain and progressive slip. The sagittal pelvic tilt index gives the examiner an objective measure of the stability of the lumbosacral junction by quantifying the relationship between S2, the center of the hip, and L5. A decreasing sagittal pelvic tilt index ratio in this preliminary series correlated with slip progression and risk of conservative treatment failure, whereas those patients with a stable sagittal pelvic tilt index did not progress and remained clinically asymptomatic.

  10. Axial magnetic field produced by axially and radially magnetized permanent rings

    International Nuclear Information System (INIS)

    Peng, Q.L.; McMurry, S.M.; Coey, J.M.D.

    2004-01-01

    Axial magnetic fields produced by axially and radially magnetized permanent magnet rings were studied. First, the axial magnetic field produced by a current loop is introduced, from which the axial field generated by an infinitely thin solenoid and by an infinitely thin current disk can be derived. Then the axial fields produced by axially and by radially magnetized permanent magnet rings can be obtained. An analytic formula for the axial fields produced by two axially magnetized rings is given. A permanent magnet with a high axial gradient field is fabricated, the measured results agree with the theoretical calculation very well. As an example, the axial periodic field produced by an arrangement of alternating axially and radially magnetized rings has been discussed

  11. View of the Axial Field Spectrometer

    CERN Multimedia

    1980-01-01

    The Axial Field Spectrometer, with the vertical uranium/scintillator calorimeter and the central drift chamber retracted for service. One coil of the Open Axial Field Magnet is just visible to the right.

  12. Identification of IGF-I in the calvarial suture of young rats: histochemical analysis of the cranial sagittal sutures in a hyperthyroid rat model.

    Science.gov (United States)

    Akita, S; Hirano, A; Fujii, T

    1996-01-01

    staining of IGF-I was markedly increased in the suture margins of the T3-treated group. There were no significant differences observed either in the skull base measurements or in the histologic and histochemical findings of the skull base or the coronal suture between the groups. More significantly, excess administration of thyroid hormone enhanced the cranial sagittal suture closure; therefore, it was proposed that local IGF-I plays an important role in sagittal sutural bone formation.

  13. Coronal Loops: Evolving Beyond the Isothermal Approximation

    Science.gov (United States)

    Schmelz, J. T.; Cirtain, J. W.; Allen, J. D.

    2002-05-01

    Are coronal loops isothermal? A controversy over this question has arisen recently because different investigators using different techniques have obtained very different answers. Analysis of SOHO-EIT and TRACE data using narrowband filter ratios to obtain temperature maps has produced several key publications that suggest that coronal loops may be isothermal. We have constructed a multi-thermal distribution for several pixels along a relatively isolated coronal loop on the southwest limb of the solar disk using spectral line data from SOHO-CDS taken on 1998 Apr 20. These distributions are clearly inconsistent with isothermal plasma along either the line of sight or the length of the loop, and suggested rather that the temperature increases from the footpoints to the loop top. We speculated originally that these differences could be attributed to pixel size -- CDS pixels are larger, and more `contaminating' material would be expected along the line of sight. To test this idea, we used CDS iron line ratios from our data set to mimic the isothermal results from the narrowband filter instruments. These ratios indicated that the temperature gradient along the loop was flat, despite the fact that a more complete analysis of the same data showed this result to be false! The CDS pixel size was not the cause of the discrepancy; rather, the problem lies with the isothermal approximation used in EIT and TRACE analysis. These results should serve as a strong warning to anyone using this simplistic method to obtain temperature. This warning is echoed on the EIT web page: ``Danger! Enter at your own risk!'' In other words, values for temperature may be found, but they may have nothing to do with physical reality. Solar physics research at the University of Memphis is supported by NASA grant NAG5-9783. This research was funded in part by the NASA/TRACE MODA grant for Montana State University.

  14. Sagittal plane kinematics of the foot during passive ankle dorsiflexion.

    Science.gov (United States)

    Gatt, Alfred; Chockalingam, Nachiappan; Chevalier, Thierry Larose

    2011-12-01

    Measurement of ankle joint dorsiflexion is an essential examination technique that needs to be performed prior to prescription of foot orthoses since the presence or absence of ankle equinus will affect the design of such devices. The purpose of this study was to investigate the effect of foot posture on sagittal plane kinematics of various foot segments during passive dorsiflexion. Comparative repeated measures design. To determine the effect of foot posture on inter segmental kinematics during passive dorsiflexion. An optoelectronic movement analysis system was employed to collect kinematic data. A validated marker set (Oxford Foot Model) was applied to 16 subjects (12 males, 4 females) with a mean age of 35.5 years (range 20-56 years), who provided informed consent. An upward force was applied to the forefoot until maximum resistance. Sagittal movement of the hindfoot and forefoot segments along with the whole foot movement were analyzed in the pronated, neutral and supinated foot postures. While maximum foot dorsiflexion angle showed a significant difference between the three postures (p = 0.000) the actual recorded difference between the neutral and supinated postures was only 2.49°. For the hindfoot and forefoot segments, mean angle range of movement for the pronated foot posture was significantly higher than the other foot postures. The forefoot to hindfoot angle demonstrated a significant (p = 0.005) increase during dorsiflexion between the pronated and supinated postures. These results indicate that during passive dorsiflexion, the forefoot travels through a greater degree of movement than the hindfoot. While the maximum foot dorsiflexion angle differs significantly between the pronated and supinated foot postures, hindfoot movement also varies significantly between foot postures. Furthermore, the forefoot to tibia angle travels through a greater range than the hindfoot to tibia angle, in all three foot postures. The hindfoot to forefoot angle does not

  15. A multi-channel coronal spectrophotometer.

    Science.gov (United States)

    Landman, D. A.; Orrall, F. Q.; Zane, R.

    1973-01-01

    We describe a new multi-channel coronal spectrophotometer system, presently being installed at Mees Solar Observatory, Mount Haleakala, Maui. The apparatus is designed to record and interpret intensities from many sections of the visible and near-visible spectral regions simultaneously, with relatively high spatial and temporal resolution. The detector, a thermoelectrically cooled silicon vidicon camera tube, has its central target area divided into a rectangular array of about 100,000 pixels and is read out in a slow-scan (about 2 sec/frame) mode. Instrument functioning is entirely under PDP 11/45 computer control, and interfacing is via the CAMAC system.

  16. Evolution of coronal and interplanetary magnetic fields

    International Nuclear Information System (INIS)

    Levine, R.H.

    1980-01-01

    Numerous studies have provided the detailed information necessary for a substantive synthesis of the empirical relation between the magnetic field of the sun and the structure of the interplanetary field. The author points out the latest techniques and studies of the global solar magnetic field and its relation to the interplanetary field. The potential to overcome most of the limitations of present methods of analysis exists in techniques of modelling the coronal magnetic field using observed solar data. Such empirical models are, in principle, capable of establishing the connection between a given heliospheric point and its magnetically-connected photospheric point, as well as the physical basis for the connection. (Auth.)

  17. Topologically driven coronal dynamics – a mechanism for coronal hole jets

    Directory of Open Access Journals (Sweden)

    D. A. N. Müller

    2008-10-01

    Full Text Available Bald patches are magnetic topologies in which the magnetic field is concave up over part of a photospheric polarity inversion line. A bald patch topology is believed to be the essential ingredient for filament channels and is often found in extrapolations of the observed photospheric field. Using an analytic source-surface model to calculate the magnetic topology of a small bipolar region embedded in a global magnetic dipole field, we demonstrate that although common in closed-field regions close to the solar equator, bald patches are unlikely to occur in the open-field topology of a coronal hole. Our results give rise to the following question: What happens to a bald patch topology when the surrounding field lines open up? This would be the case when a bald patch moves into a coronal hole, or when a coronal hole forms in an area that encompasses a bald patch. Our magnetostatic models show that, in this case, the bald patch topology almost invariably transforms into a null point topology with a spine and a fan. We argue that the time-dependent evolution of this scenario will be very dynamic since the change from a bald patch to null point topology cannot occur via a simple ideal evolution in the corona. We discuss the implications of these findings for recent Hinode XRT observations of coronal hole jets and give an outline of planned time-dependent 3-D MHD simulations to fully assess this scenario.

  18. [Effects of wide posterior release on the correction of severe and rigid thoracic scoliosis in sagittal plane].

    Science.gov (United States)

    Zhang, Guo-ying; Zhang, Yong-gang; Zhang, Xue-song; Wang, Zheng; Mao, Ke-ya; Wang, Yan

    2013-02-19

    To explore the effects of wide posterior release on the correction of severe and rigid thoracic scoliosis in sagittal plane. A total of 37 idiopathic scoliosis patients (26 females and 11 males) with severe and rigid thoracic curves corrected with posterior pedicle screw system between 2006 and 2009 were recruited. Their average age was 17.3 years (range: 14 - 22) at operation and the thoracic Cobb angle was between 70 - 100°. They were separated into 2 groups: group A (n = 15) with wide posterior release and group B (n = 22) with posterior soft tissue release alone. The preoperative, postoperative and latest standing posteroanterior and lateral radiographs during follow-ups were reviewed. All patients were operated successfully. No statistic difference existed in the average operative duration between two groups (P > 0.05). The average volume of blood loss was 874 ml in Group A versus 712 ml in Group B (P subgroup A1 (preoperative TKA subgroup A2 (preoperative TKA > 40°) in group A and subgroup B1 (preoperative TKA subgroup B2 (preoperative TKA > 40°) in group B. The postoperative TKA was 26.8° (> 9.2° than preoperation) in subgroup A1 and 12.5° (3.1° subgroup B1 (P subgroup A2 and 39.1° (10.3° subgroup B2 (P < 0.05). There was one case of dural leakage in group A. A leakage of cerebrospinal fluid was cured with a prone position and wound compression. One case of infection in superficial part of wound in group B was cured after debridement. No nerve system injury, deep infection or instrumentation failure was found. During a follow-up period of 2 years, there was no obvious correction loss or trunk decompensation. In idiopathic scoliosis patients with severe and rigid thoracic curves, wide posterior release via a posterior approach may help to correct the deformity in sagittal plan and achieve more coronal correction in these curves.

  19. Relationship of EUV Irradiance Coronal Dimming Slope and Depth to Coronal Mass Ejection Speed and Mass

    Science.gov (United States)

    Mason, James Paul; Woods, Thomas N.; Webb, David F.; Thompson, Barbara J.; Colaninno, Robin C.; Vourlidas, Angelos

    2016-01-01

    Extreme ultraviolet (EUV) coronal dimmings are often observed in response to solar eruptive events. These phenomena can be generated via several different physical processes. For space weather, the most important of these is the temporary void left behind by a coronal mass ejection (CME). Massive, fast CMEs tend to leave behind a darker void that also usually corresponds to minimum irradiance for the cooler coronal emissions. If the dimming is associated with a solar are, as is often the case, the are component of the irradiance light curve in the cooler coronal emission can be isolated and removed using simultaneous measurements of warmer coronal lines. We apply this technique to 37dimming events identified during two separate two-week periods in 2011, plus an event on 2010 August 7 analyzed in a previous paper, to parameterize dimming in terms of depth and slope. We provide statistics on which combination of wavelengths worked best for the flare-removal method, describe the fitting methods applied to the dimming light curves, and compare the dimming parameters with corresponding CME parameters of mass and speed. The best linear relationships found are nu(sub CME) [km/s] approx. equals 2.36 x 10 6 [km/%] x s(sub dim) [%/s] m(sub CME) [g] approx. equals 2.59 x 10(exp.15 [g/%] x the square root of d(sub dim) [%].These relationships could be used for space weather operations of estimating CME mass and speed using near-real-time irradiance dimming measurements.

  20. Evaluations of multiplanar reconstruction in CT recognition of lumbar disk disease

    Energy Technology Data Exchange (ETDEWEB)

    Rosenthal, D.I.; Stauffer, A.E.; Davis, K.R.; Ganott, M.; Taveras, J.M.

    1984-07-01

    Axial computed tomographic (CT) images were compared with sagittal and coronal reformations and myelograms in 60 patients to evaluate the diagnostic usefulness of multiplanar reconstructions for the recognition of lumbar disk disease. The axial CT scans were most sensitive and specific. The sagittal scans were helpful in evaluating the neural foramina, the size of the disk bulge into the spinal canal, especially at L5-S1, and patients with spondylolisthesis. The coronal images were the least informative, although they contributed to the evaluation of lumbar nerve roots. The myelograms and the sagittal images were equally useful in the detection of herniated disk, but axial scans were superior to either. It was concluded that reformatted sagittal and coronal images are not required if all axial images are normal.

  1. Sagittal plane momentum control during walking in elderly fallers.

    Science.gov (United States)

    Fujimoto, Masahiro; Chou, Li-Shan

    2016-03-01

    The purpose of this study was to examine sagittal plane momentum control during walking with the use of center of mass (COM) velocity and acceleration. COM control in the antero-posterior direction during walking of healthy young and elderly adults, and elderly fallers (n=15/group) was examined. Using a single-link-plus-foot inverted pendulum model, boundaries for the region of stability were determined based on the COM position at toe-off and its instantaneous velocity or the peak acceleration prior to toe-off (ROSv or ROSa, respectively). Although no significant difference in forward COM velocity was detected between healthy young and elderly subjects, the peak forward COM acceleration differed significantly, suggesting age-related differences in momentum control during walking. Elderly fallers demonstrated significantly slower forward COM velocities and accelerations and placed their COM significantly more anterior than healthy young and elderly subjects at toe-off, which resulted in their COM position-velocity combination located within the ROSv. Similar results were obtained in the ROSa, where elderly fallers demonstrated a larger stability margin than healthy young and elderly subjects. Significantly slower peak COM accelerations could be indicative of a poor momentum control ability, which was more pronounced in elderly fallers. Examining COM acceleration, in addition to its velocity, would provide a greater understanding of person's momentum control, which would allow us to better reveal underlying mechanisms of gait imbalance or falls. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Human foot placement and balance in the sagittal plane.

    Science.gov (United States)

    Millard, Matthew; Wight, Derek; McPhee, John; Kubica, Eric; Wang, David

    2009-12-01

    Foot placement has long been recognized as the primary mechanism that humans use to restore balance. Many biomechanists have examined where humans place their feet during gait, perturbations, and athletic events. Roboticists have also used foot placement as a means of control but with limited success. Recently, Wight et al. (2008, "Introduction of the Foot Placement Estimator: A Dynamic Measure of Balance for Bipedal Robotics," ASME J. Comput. Nonlinear Dyn., 3, p. 011009) introduced a planar foot placement estimator (FPE) algorithm that will restore balance to a simplified biped that is falling. This study tested the FPE as a candidate function for sagittal plane human-foot-placement (HFP) by recording the kinematics of 14 healthy subjects while they performed ten walking trials at three speeds. The FPE was highly correlated with HFP (rho>or=0.997) and its accuracy varied linearly from 2.6 cm to -8.3 cm as walking speed increased. A sensitivity analysis revealed that assumption violations of the FPE cannot account for the velocity-dependent changes in FPE-HFP error suggesting that this behavior is volitional.

  3. Assessment of Gender Dimorphism on Sagittal Cephalometry in Pakistani Population

    International Nuclear Information System (INIS)

    Qamruddin, I.; Shahid, F.; Tanveer, S.; Mukhtiar, M.; Asim, Z.; Alam, M. K.

    2016-01-01

    Objective: To determine and compare the cephalometric values among Pakistani males and females using commonly used sagittal skeletal measurements (ANB, Wits appraisal, Beta-angle) and newly developed cephalometric analyses (Yen-angle and W-angle). Study Design: Observational, cross-sectional study. Place and Duration of Study: Orthodontic Department of Baqai Medical University, Karachi, Pakistan, from August to October 2013. Methodology: A total of 209 pre-treatment lateral cephalometric radiographs of orthodontic patients were selected from departmental records, comprised of 92 males and 117 females. Radiographs were traced for measurements of ANB, Wits appraisal, Beta-angle, W-angle and Yen-angle. Patients were categorized into skeletal classes I, II, and III on the basis of performed measurements, incisor classification, and profile recorded from their records. Descriptive analysis was used to obtain median interquartile range in both the genders and Mann-Whitney U-test was used to observe gender dimorphism. Result: Skeletal class II was the most prevalent type of malocclusion. There were no difference in the obtained measurements between males and females except the Wits appraisal and Beta-angle in class II patients, which showed significant difference in values (p < 0.05). Conclusion: Pakistani population has no significant different difference in the craniofacial morphology of males and females, with the exception of Wits-appraisal and Beta-angle in class II cases. (author)

  4. Sagittal venous sinus thrombosis after cesarean section: a case report

    Directory of Open Access Journals (Sweden)

    Farideh Keypour

    2013-07-01

    Full Text Available Background: Cerebral venous thrombosis (CVT is uncommon after cesarean section. Although it can be a leading cause of maternal mortality. CVT may occur during pregnancy because of hypercoagulable states such as preeclampsia, thrombophilias, antiphospholipid antibody syndrome and sepsis.Case presentation: A 31 years old woman G2 Ab1 at 37 weeks gestational age with  premature rupture of membrane underwent cesarean section because breech presentation and preeclampsia. Spinal anesthesia was done for emergent cesarean section. On the second day after cesarean section, she developed headache, vomiting, focal neurologic deficits, paresthesia, blurred vision. Brain magnetic resonance imaging (MRI showed thrombosis in anterior half of superior sagittal sinus. Treatment consisted of anticoagulation.  Conclusion: Thrombophilias, pregnancy-related hypertension and cesarean section are the predisposing factors for thromboembolism. Unfractionated heparin and low molecular weight heparin (LMWs are effective drugs for thromboprophylaxis. It is vital to prevent venous thrombosis to reduce mortality during both intrapartum and postpartum periods. Consideration of cerebral venous thrombosis in similar cases is recommended.

  5. Assessment of Gender Dimorphism on Sagittal Cephalometry in Pakistani Population.

    Science.gov (United States)

    Qamruddin, Irfan; Alam, Mohammad Khursheed; Shahid, Fazal; Tanveer, Sadaf; Mukhtiar, Marvi; Asim, Zainab

    2016-05-01

    To determine and compare the cephalometric values among Pakistani males and females using commonly used sagittal skeletal measurements (ANB, Wits appraisal, Beta-angle) and newly developed cephalometric analyses (Yen-angle and W-angle). Observational, cross-sectional study. Orthodontic Department of Baqai Medical University, Karachi, Pakistan, from August to October 2013. Atotal of 209 pre-treatment lateral cephalometric radiographs of orthodontic patients were selected from departmental records, comprised of 92 males and 117 females. Radiographs were traced for measurements of ANB, Wits appraisal, Beta-angle, W-angle and Yen-angle. Patients were categorized into skeletal classes I, II, and III on the basis of performed measurements, incisor classification, and profile recorded from their records. Descriptive analysis was used to obtain median interquartile range in both the genders and Mann-Whitney U-test was used to observe gender dimorphism. Skeletal class II was the most prevalent type of malocclusion. There were no difference in the obtained measurements between males and females except the Wits appraisal and Beta-angle in class II patients, which showed significant difference in values (p < 0.05). Pakistani population has no significant different difference in the craniofacial morphology of males and females, with the exception of Wits-appraisal and Beta-angle in class II cases.

  6. Featured Image: Waves in a Coronal Fan

    Science.gov (United States)

    Kohler, Susanna

    2017-09-01

    The inset in this Solar Dynamics Observatory image shows a close-up view of a stunning coronal fan extending above the Suns atmosphere. These sweeping loops were observed on 7 March 2012 by a number of observatories, revealing the first known evidence of standing slow magnetoacoustic waves in cool coronal fan loops. The oscillations of the loops, studied in a recent article led by Vaibhav Pant (Indian Institute of Astrophysics), were triggered by blast waves that were generated by X-class flares from the distant active region AR 11429 (marked withthe yellow box at left). The overplotted X-ray curve in the top right corner of the image (click for the full view) shows the evolution of the flares that perturbed the footpoints of the loops. You can check out the video of the action below, and follow the link to the original article to read more about what these oscillations tell us about the Suns activity. CitationV. Pant et al 2017 ApJL 847 L5. doi:10.3847/2041-8213/aa880f

  7. Extreme ultraviolet observations of coronal holes. II

    International Nuclear Information System (INIS)

    Bohlin, J.D.; Sheeley, N.R. Jr.

    1978-01-01

    Extreme-ultraviolet Skylab and ground-based solar magnetic field data have been combined to study the origin and evolution of coronal holes. It is shown that holes exist only within the large-scale unipolar magnetic cells into which the solar surface is divided at any given time. A well-defined boundary zone usually exists between the edge of a hole and the neutral line which marks the edge of its magnetic cell. This boundary zone is the region across which a cell is connected by magnetic arcades with adjacent cells of opposite polarity. Three pieces of observational evidence are offered to support the hypothesis that the magnetic lines of force from a hole are open. Kitt Peak magnetograms are used to show that, at least on a relative scale, the average field strengths within holes are quite variable, but indistinguishable from the field strengths in other quiet parts of the Sun's surface. Finally it is shown that the large, equatorial holes characteristic of the declining phase of the last solar cycle during Skylab (1973-74) were all formed as a result of the mergence of bipolar magnetic regions (BMR's), confirming an earlier hypothesis by Timothy et al. (1975). Systematic application of this model to the different aspects of the solar cycle correctly predicts the occurrence of both large, equatorial coronal holes (the 'M-regions' which cause recurrent geomagnetic storms) and the polar cap holes. (Auth.)

  8. Plasma Evolution within an Erupting Coronal Cavity

    Science.gov (United States)

    Long, David M.; Harra, Louise K.; Matthews, Sarah A.; Warren, Harry P.; Lee, Kyoung-Sun; Doschek, George A.; Hara, Hirohisa; Jenkins, Jack M.

    2018-03-01

    Coronal cavities have previously been observed to be associated with long-lived quiescent filaments and are thought to correspond to the associated magnetic flux rope. Although the standard flare model predicts a coronal cavity corresponding to the erupting flux rope, these have only been observed using broadband imaging data, restricting an analysis to the plane-of-sky. We present a unique set of spectroscopic observations of an active region filament seen erupting at the solar limb in the extreme ultraviolet. The cavity erupted and expanded rapidly, with the change in rise phase contemporaneous with an increase in nonthermal electron energy flux of the associated flare. Hot and cool filamentary material was observed to rise with the erupting flux rope, disappearing suddenly as the cavity appeared. Although strongly blueshifted plasma continued to be observed flowing from the apex of the erupting flux rope, this outflow soon ceased. These results indicate that the sudden injection of energy from the flare beneath forced the rapid eruption and expansion of the flux rope, driving strong plasma flows, which resulted in the eruption of an under-dense filamentary flux rope.

  9. Analytical investigations on the Coronation Gospels manuscript.

    Science.gov (United States)

    Aceto, Maurizio; Agostino, Angelo; Fenoglio, Gaia; Idone, Ambra; Crivello, Fabrizio; Griesser, Martina; Kirchweger, Franz; Uhlir, Katharina; Puyo, Patricia Roger

    2017-01-15

    The Coronation Gospels or Krönungsevangeliar is a manuscript kept in Vienna at the Kunsthistorisches Museum Wien, datable to the end of VIII century A.D. and produced at Charlemagne court. It is an example of a purple codex, i.e. its parchment is coloured in purple. It has to be considered as one of the most important medieval codices, according to its use to take oath in the coronation ceremony of kings and emperors of the Holy Roman Empire up to 1792. In order to gather information of the manufacture of the manuscript and its present conservation state, a diagnostic investigation campaign has been carried out in situ with totally non-invasive techniques. X-ray Fluorescence Spectrometry (XRF), UV-visible diffuse reflectance spectrophotometry with optical fibres (FORS), spectrofluorimetry, optical microscopy and multispectral analysis have been applied in order to identify the colourants used in the decoration of the manuscript, with the main concern to the dye used to impart the purple hue to the parchment. The information collected was useful in order to address some of the questions raised by art historians concerning its history. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Analytical investigations on the Coronation Gospels manuscript

    Science.gov (United States)

    Aceto, Maurizio; Agostino, Angelo; Fenoglio, Gaia; Idone, Ambra; Crivello, Fabrizio; Griesser, Martina; Kirchweger, Franz; Uhlir, Katharina; Puyo, Patricia Roger

    2017-01-01

    The Coronation Gospels or Krönungsevangeliar is a manuscript kept in Vienna at the Kunsthistorisches Museum Wien, datable to the end of VIII century A.D. and produced at Charlemagne court. It is an example of a purple codex, i.e. its parchment is coloured in purple. It has to be considered as one of the most important medieval codices, according to its use to take oath in the coronation ceremony of kings and emperors of the Holy Roman Empire up to 1792. In order to gather information of the manufacture of the manuscript and its present conservation state, a diagnostic investigation campaign has been carried out in situ with totally non-invasive techniques. X-ray Fluorescence Spectrometry (XRF), UV-visible diffuse reflectance spectrophotometry with optical fibres (FORS), spectrofluorimetry, optical microscopy and multispectral analysis have been applied in order to identify the colourants used in the decoration of the manuscript, with the main concern to the dye used to impart the purple hue to the parchment. The information collected was useful in order to address some of the questions raised by art historians concerning its history.

  11. Mid-term periodicities and heliospheric modulation of coronal index ...

    Indian Academy of Sciences (India)

    PRITHVI RAJ SINGH

    2018-03-06

    Mar 6, 2018 ... long-term periodicity of ∼11 years, with different solar activities. The physical processes that occur inside the. Sun are reflected by a periodic character in terms of coronal index of coronal emission (Fe XIV 530.3 nm) during solar activity cycles. Recently, a link between the strength of photospheric magnetic ...

  12. Association of solar coronal loops to photospheric magnetic field

    Science.gov (United States)

    Pradeep Chitta, Lakshmi; Peter, Hardi; Solanki, Sami

    2017-08-01

    Magnetic connectivity and its evolution from the solar photosphere to the corona will play a crucial role in the energetics of the solar atmosphere. To explore this connectivity, we use high spatial resolution magnetic field observations of an active region from the balloon-borne SUNRISE telescope, in combination with the observations of coronal loops imaged in extreme ultraviolet by SDO/AIA. We show that photospheric magnetic field at the base of coronal loops is rapidly evolving through small-scale flux emergence and cancellation events with rates on the order of 10^15 Mx/s. When observed at high spatial resolution better than 0.5 arcsec, we find that basically all coronal loops considered so far are rooted in the photosphere above small-scale opposite polarity magnetic field patches. In the photosphere, the magnetic field threading coronal loops is interacting with opposite polarity parasitic magnetic concentrations leading to dynamic signatures in the upper atmosphere. Chromospheric small-scale jets aligned to coronal loops are observed at these locations. We will present preliminary results from 3D MHD simulations of coronal loops driven by realistic magneto-convection and discuss what role the magnetic interactions at coronal loop footpoints could play in the evolution of coronal loops and their heating.

  13. Solar Cycle Variation of Interplanetary Coronal Mass Ejection ...

    Indian Academy of Sciences (India)

    2010-08-25

    Aug 25, 2010 ... Spörer's sunspot law at low latitudes (thus, no 'butterfly diagram'); how- ever, at high latitudes, there may be a poleward motion and an equator- ward motion from the rise to the maximum to the declining phases. Key words. Sun: activity, coronal mass ejections (CMEs). 1. Introduction. Interplanetary coronal ...

  14. Wing Morphometry and Genetic Variability Between Culex coronator and Culex usquatus (Diptera: Culicidae), Two Sibling Species of the Coronator Group.

    Science.gov (United States)

    Demari-Silva, Bruna; Multini, Laura Cristina; Suesdek, Lincoln; Oliveira, Tatiane M P; Sallum, Maria Anice Mureb; Marrelli, Mauro Toledo

    2017-07-01

    Culex coronator Dyar and Knab and Culex usquatus Dyar belong to the Coronator Group of the subgenus Culex. Culex coronator and Cx. usquatus are widespread and sympatric throughout their distribution range, which includes Brazil. Morphological identification of these species is based primarily on the characteristics of the male genitalia; females are indistinguishable using the qualitative characteristics employed in identification keys. The primary objective of this study was to distinguish females of Cx. coronator from those of Cx. usquatus employing both wing geometric morphometrics, and DNA sequences (NADH5, COI, Hunchback, and CAD). Additionally, we employed the isolation with migration model (IMa) to evaluate: 1) the migration rates and 2) the divergence time, between Cx. coronator and Cx. usquatus. Specimens were captured in Pariquera-Açu and Cananéia south-eastern São Paulo, Ribeira Valley, Brazil. Canonical variate analysis (CVA) demonstrated two groups in the morphospace. The accuracy of species recognition was moderate (82.6%) for Cx. coronator and low (60.8%) for Cx. usquatus. Bayesian analyses of concatenated gene sequences recovered from specimens of Cx. coronator separated the species into three lineages (herein referred to as Culex coronator A, B, and C), whereas Cx. usquatus specimens clustered into a single lineage. Lineages A and B of Cx. coronator intermixed with specimens of Cx. usquatus, and one specimen of Cx. coronator clustered into the Cx. usquatus lineage. The IMa analysis indicated that the divergence of Cx. coronator and Cx. usquatus is a slow process, with some degree of gene flow between the two species. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. Coronal heating in coupled photosphere-chromosphere-coronal systems: turbulence and leakage

    Science.gov (United States)

    Verdini, A.; Grappin, R.; Velli, M.

    2012-02-01

    Context. Coronal loops act as resonant cavities for low-frequency fluctuations that are transmitted from the deeper layers of the solar atmosphere. These fluctuations are amplified in the corona and lead to the development of turbulence that in turn is able to dissipate the accumulated energy, thus heating the corona. However, trapping is not perfect, because some energy leaks down to the chromosphere on a long timescale, limiting the turbulent heating. Aims: We consider the combined effects of turbulence and energy leakage from the corona to the photosphere in determining the turbulent energy level and associated heating rate in models of coronal loops, which include the chromosphere and transition region. Methods: We use a piece-wise constant model for the Alfvén speed in loops and a reduced MHD-shell model to describe the interplay between turbulent dynamics in the direction perpendicular to the mean field and propagation along the field. Turbulence is sustained by incoming fluctuations that are equivalent, in the line-tied case, to forcing by the photospheric shear flows. While varying the turbulence strength, we systematically compare the average coronal energy level and dissipation in three models with increasing complexity: the classical closed model, the open corona, and the open corona including chromosphere (or three-layer model), with the last two models allowing energy leakage. Results: We find that (i) leakage always plays a role. Even for strong turbulence, the dissipation time never becomes much lower than the leakage time, at least in the three-layer model; therefore, both the energy and the dissipation levels are systematically lower than in the line-tied model; (ii) in all models, the energy level is close to the resonant prediction, i.e., assuming an effective turbulent correlation time longer than the Alfvén coronal crossing time; (iii) the heating rate is close to the value given by the ratio of photospheric energy divided by the Alfv

  16. Lumbar Facet Joint Arthritis Is Associated with More Coronal Orientation of the Facet Joints at the Upper Lumbar Spine

    International Nuclear Information System (INIS)

    Jentzsch, Th.; Geiger, J.; Zimmermann, S.M.; Slankamenac, K.; Werner, C.M.L.; Nguyen-Kim, Th.D.L.

    2013-01-01

    We retrospectively analyzed CT scans of 620 individuals, who presented to our traumatology department between 2008 and 2010. Facet joint (FJ) arthritis was present in 308 (49.7%) individuals with a mean grade of 1. It was seen in 27% of individuals ≤40 years and in 75% of individuals ≥41 years ( Ρ <0.0001) as well as in 52% of females and 49% of males ( Ρ=0.61). Mean FJ orientation was 30.4° at L2/3, 38.7° at L3/4, 47° at L4/5, and 47.3° at L5/S1. FJ arthritis was significantly associated with more coronal (increased degree) FJ orientation at L2/3 (Ρ=0.03) with a cutoff point at ≥32°. FJs were more coronally oriented (48.8°) in individuals ≤40 years and more sagittally oriented (45.6°) in individuals ≥41 years at L5/S1 (Ρ=0.01). Mean FJ asymmetry was 4.89° at L2/3, 6.01° at L3/4, 6.67° at L4/5, and 7.27° at L5/S1, without a significant difference for FJ arthritis. FJ arthritis is common, increases with age, and affects both genders equally. More coronally oriented FJs (≥32°) in the upper lumbar spine may be an individual risk factor for development of FJ arthritis.

  17. Quality of coroner's post-mortems in a UK hospital.

    Science.gov (United States)

    Al Mahdy, Husayn

    2014-01-01

    The aim of this paper was, principally, to look at the coroner's post-mortem report quality regarding adult medical patients admitted to an English hospital; and to compare results with Royal College of Pathologists guidelines. Hospital clinical notes of adult medical patients dying in 2011 and who were referred to the coroner's office to determine the cause of death were scrutinised. Their clinical care was also reviewed. There needs to be a comprehensive approach to coroner's post-mortems such as routinely taking histological and microbiological specimens. Acute adult medical patient care needs to improve. Steps should be taken to ensure that comprehensive coroner's post-mortems are performed throughout the UK, including with routine histological and microbiological specimens examination. Additionally, closer collaboration between clinicians and pathologists needs to occur to improve emergency adult medical patient clinical care. The study highlights inadequacies in coroner's pathology services.

  18. Axial diagnostic package for Z

    International Nuclear Information System (INIS)

    Nash, T.J.; Derzon, M.S.; Chandler, G.

    1998-06-01

    The authors have developed and fielded an axial diagnostic package for the 20 MA, 100 ns, z-pinch driver Z. The package is used to diagnose dynamic hohlraum experiments which require an axial line of sight. The heart of the package is a reentrant cone originally used to diagnose ion-beam-driven hohlraums on PBFA-H. It has one diagnostic line of sight at 0 degrees, 4 at 6 degrees, and 4 at 9 degrees. In addition it has a number of viewing, alignment, and vacuum feedthrough ports. The front of the package sits approximately 5 feet from the pinch. This allows much closer proximity to the pinch, with inherently better resolution and signal, than is presently possible in viewing the pinch from the side. Debris that is preferentially directed along the axis is mitigated by two apertures for each line of sight, and by fast valves and imaging pinholes or cross slits for each diagnostic. In the initial run with this package they fielded a time resolved pinhole camera, a five-channel pinhole-apertured x-ray diode array, a bolometer, a spatially resolved time-integrated crystal spectrometer, and a spatially and temporally resolved crystal spectrometer. They present data obtained from these diagnostics in the dynamic hohlraum research conducted on Z

  19. Defining the pubic symphysis angle with respect to the coronal plane - Clinical and biomechanical considerations.

    Science.gov (United States)

    Link, B-C; Ha, N B; Solomon, L B; Rickman, M

    2017-07-01

    Fixation strength of constructs placed across the pubic symphysis after injury is dependent on screw length, maximisation of which requires knowledge of the bony anatomy. The aim of this study was to describe the ideal angle of drilling to achieve maximal safe screw placement within the pubic body. Furthermore, the influences of age and gender on the skeletal topography were investigated. Three hundred CT scans of patients without pelvic injury were analysed to record the angle of the pubic body (APB) with respect to the coronal plane, and the depth of the pubic body (DPB) in the sagittal plane. Mean APB and DPB were 54.69° and 55.35mm, respectively. Females had a significantly higher mean APB than males (57.29° vs. 52.41°; prespect to the operating table will allow maximal screw length, which should be in the region of 55mm. The mean width of the pubic body should allow for placement of a 3.5 or 4.5mm diameter screw. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Resolution of the more anteriorly positioned psoas muscle following correction of spinal sagittal alignment from spondylolisthesis: case report.

    Science.gov (United States)

    Syed, Hasan R; Yaeger, Kurt; Sandhu, Faheem A

    2017-04-01

    Several studies have described the radiographic, histological, and morphological changes to the paraspinal muscle in patients with chronic low-back pain due to degenerative diseases of the spine. Gross anatomical illustrations have shown that the psoas muscle lies lateral to the L4-5 vertebrae and subsequently thins and dissociates from the vertebral body at L5-S1 in a ventrolateral course. A "rising psoas" may influence the location of the lumbar plexus and result in transient neurological injury on lateral approach to the spine. It is postulated that axial back pain may be exacerbated by anatomical changes of paraspinal musculature as a direct result of degenerative spine conditions. To their knowledge, the authors present the first reported case of a more anteriorly positioned psoas muscle and its resolution following correction of spondylolisthesis in a 62-year-old woman. This case highlights the dynamic nature of degenerative spinal disorders and illustrates that psoas muscle position can be affected by sagittal balance. Normal anatomical positioning can be restored following correction of spinal alignment.

  1. A comparison of standard definitions and sagittal abdominal ...

    Science.gov (United States)

    Introduction: Metabolic syndrome (MeTS) is the cluster of several clinical symptoms that together represent the strongest risk factor for cardiovascular disease. The prevalence of MeTS in adolescents is difficult to estimate given that there are several, but no agreed upon definition of MeTS for this age group. It is important to estimate MeTS and identify at-risk adolescents early in order to provide effective interventions prior to the development of diabetes and coronary heart disease. Objective: Study objectives are to: (1) estimate the prevalence of MeTS in U.S. adolescents using three widely adopted definitions and (2) compare changes in prevalence of MeTS when utilizing sagittal abdominal diameter (SAD) as a component of MeTS. Methods: Data from U.S. adolescents ages 12–19 years (N=970) in the NHANES (2011–2014) were analyzed. MeTS standard definitions developed by Cook et al. (2003), deFerranti et al. (2007), and the International Disease Federation (IDF, 2007) were applied to estimate the sex-stratified, weighted prevalence of MeTS and its individual components (i.e., high waist circumference (WC), hypertension, blood lipid abnormalities, and high fasting blood glucose (FBG)). The definitions were modified by substituting SAD for WC, and weighted MeTS prevalence was re-estimated. Results: Regardless of gender and definition, abnormal blood lipids and high WC were the most prevalent MeTS components. For both sexes, estimated prevalence of componen

  2. SAGITTAL DIAMETER OF FORAMEN MAGNUM IN NORMAL POPULATION: AN MRI STUDY

    OpenAIRE

    Lakshmi

    2015-01-01

    Lower position of cerebellar tonsils was frequently noticed in Western studies. In some of the studies, sagittal diameter of foramen magnum was found to be larger in cases of Chiari malformation. However, there are no Indian studies for comparison. Our study was proposed to determine the standard values for sagittal diameter of foramen magnum in various age groups and both sexes. This gives a guideline for further studies in pathological conditions like Craniovertebral Junctional ...

  3. The Role of Proprioception in the Sagittal Setting of Anticipatory Postural Adjustments During Gait Initiation

    OpenAIRE

    Pereira Marcelo P.; Pelicioni Paulo H. Silva; Gobbi Lilian T.B.

    2015-01-01

    Purpose. Previous studies have studied the role of proprioception on the setting of anticipatory postural adjustments (APA) during gait initiation. However, these studies did not investigate the role of proprioception in the sagittal APA setting. We aimed to investigate the role of proprioception manipulation to induce APA sagittal adaptations on gait initiation. Methods. Fourteen healthy adults performed gait initiation without, and with, vibration applied before movement onset, and during m...

  4. Superior sagittal sinus thrombosis: a rare complication in a child with nephrotic syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Pirogovsky, A.; Adi, M.; Barzilai, N. [Dept. of Radiology, Kaplan Medical Center, Rehovot (Israel); Dagan, A.; Sinai, L.; Sthoeger, D. [Div. of Paediatrics, Kaplan Medical Center, Rehovot (Israel); Tabachnik, E. [Div. of Paediatrics, Kaplan Medical Center, Rehovot (Israel); Paediatric ICU, Kaplan Hospital, Rehovot (Israel)

    2001-10-01

    A 2-year-old boy with new-onset nephrotic syndrome developed recurrent vomiting, apathy and papilloedema. Superior sagittal sinus thrombosis was diagnosed on cranial CT and MRI. He gradually recovered after treatment with heparin, fresh frozen plasma and warfarin with complete resolution of the thrombosis after 1 month. Superior sagittal sinus thrombosis is an extremely rare complication of nephrotic syndrome in children. Early diagnosis is essential for institution of anticoagulation therapy and a successful outcome. (orig.)

  5. Superior sagittal sinus thrombosis: a rare complication in a child with nephrotic syndrome

    International Nuclear Information System (INIS)

    Pirogovsky, A.; Adi, M.; Barzilai, N.; Dagan, A.; Sinai, L.; Sthoeger, D.; Tabachnik, E.

    2001-01-01

    A 2-year-old boy with new-onset nephrotic syndrome developed recurrent vomiting, apathy and papilloedema. Superior sagittal sinus thrombosis was diagnosed on cranial CT and MRI. He gradually recovered after treatment with heparin, fresh frozen plasma and warfarin with complete resolution of the thrombosis after 1 month. Superior sagittal sinus thrombosis is an extremely rare complication of nephrotic syndrome in children. Early diagnosis is essential for institution of anticoagulation therapy and a successful outcome. (orig.)

  6. Sagittal Plane Knee Biomechanics and Vertical Ground Reaction Forces Are Modified Following ACL Injury Prevention Programs

    OpenAIRE

    Padua, Darin A.; DiStefano, Lindsay J.

    2009-01-01

    Context: Injuries to the anterior cruciate ligament (ACL) occur because of excessive loading on the knee. ACL injury prevention programs can influence sagittal plane ACL loading factors and vertical ground reaction force (VGRF). Objective: To determine the influence of ACL injury prevention programs on sagittal plane knee biomechanics (anterior tibial shear force, knee flexion angle/moments) and VGRF. Data Sources: The PubMed database was searched for studies published between January 1988 an...

  7. Turbulent resistive heating of solar coronal arches

    Science.gov (United States)

    Benford, G.

    1983-01-01

    The possibility that coronal heating occurs by means of anomalous Joule heating by electrostatic ion cyclotron waves is examined, with consideration given to currents running from foot of a loop to the other. It is assumed that self-fields generated by the currents are absent and currents follow the direction of the magnetic field, allowing the plasma cylinder to expand radially. Ion and electron heating rates are defined within the cylinder, together with longitudinal conduction and convection, radiation and cross-field transport, all in terms of Coulomb and turbulent effects. The dominant force is identified as electrostatic ion cyclotron instability, while ion acoustic modes remain stable. Rapid heating from an initial temperature of 10 eV to 100-1000 eV levels is calculated, with plasma reaching and maintaining a temperature in the 100 eV range. Strong heating is also possible according to the turbulent Ohm's law and by resistive heating.

  8. Endogenous Magnetic Reconnection in Solar Coronal Loops

    Science.gov (United States)

    Asgari-Targhi, M.; Coppi, B.; Basu, B.; Fletcher, A.; Golub, L.

    2017-12-01

    We propose that a magneto-thermal reconnection process occurring in coronal loops be the source of the heating of the Solar Corona [1]. In the adopted model, magnetic reconnection is associated with electron temperature gradients, anisotropic electron temperature fluctuations and plasma current density gradients [2]. The input parameters for our theoretical model are derived from the most recent observations of the Solar Corona. In addition, the relevant (endogenous) collective modes can produce high energy particle populations. An endogenous reconnection process is defined as being driven by factors internal to the region where reconnection takes place. *Sponsored in part by the U.S. D.O.E. and the Kavli Foundation* [1] Beafume, P., Coppi, B. and Golub, L., (1992) Ap. J. 393, 396. [2] Coppi, B. and Basu, B. (2017) MIT-LNS Report HEP 17/01.

  9. Influence of age and sagittal balance of the spine on the value of the pelvic incidence.

    Science.gov (United States)

    Jean, Legaye

    2014-07-01

    The pelvic incidence (PI) was recognized as the key factor of the sagittal balance of the spine. Its value was described own for each individual and unchanged during adulthood. To bring out the effect of the age and of a sagittal imbalance in the variability of the value of PI. 200 subjects with chronic low back pain due to sagittal imbalance were compared to 89 normal subjects. For each groups, the cases were divided according to the age (19-40, 6-40 years, over 60 years). The PI and the sagittal positional parameters were measured on large radiographs in standardized standing position. The correlation between age and PI was observed significant only for the >60 years cases. The mean values of PI were significantly greater for these cases. An increase of the value of PI was attributable to a twisting mobilization within the sacroiliac joint. It results from a forward projection of the gravity due to a sagittal disturbance and a pelvic compensatory backward rotation. This twisting into the sacroiliac joint was incriminated in the origin of chronic low back pain. The sagittal pelvi-spinal imbalance may be incriminated in the increasing of the value of PI by a painful destabilization sacro-iliac, with leads to an increasing of the value of PI.

  10. The longitudinal sagittal growth changes of maxilla and mandible according to quantitative cervical vertebral maturation.

    Science.gov (United States)

    Chen, Lili; Lin, Jiuxiang; Xu, Tianmin; Long, Xiaosi

    2009-04-01

    To investigate the longitudinal sagittal growth changes of maxilla and mandible according to the quantitative cervical vertebral maturation (QCVM) for adolescents with normal occlusion, mixed longitudinal data were used. The samples included 87 adolescents aged from 8 to 18 y old with normal occlusion (32 males, 55 females) selected from 901 candidates. Sequential lateral cephalograms and hand-wrist films were taken once a year, lasting for 6 y. The longitudinal sagittal growth changes of maxilla and mandible according to QCVM were measured. There were some significant differences between maxilla and mandible according to QCVM. The sagittal growth change of maxilla showed a trend towards high velocity-->decelerating velocity-->completing velocity from QCVM stage I to stage IV. The sagittal growth change of mandible showed a trend towards accelerating velocity-->high velocity-->decelerating velocity-->completing velocity from QCVM stage I to stage IV. With sagittal relationship, growth magnitude was almost the same between maxilla and mandible at QCVM stage I. At stage II the growth of mandible exceeded that of maxilla and growth in mandible continued at stages III and IV, while the maxilla ceased to grow. Growth magnitude was greater and the growth duration was longer with male mandible. It is concluded that the longitudinal sagittal growth changes of maxilla and mandible on the basis of QCVM is of value in the orthodontic practice.

  11. Tracking errors in tractography of the gastrocnemius muscle. A comparison between the transverse and sagittal planes

    International Nuclear Information System (INIS)

    Aoki, Takako; Tohdoh, Yukihiro; Tawara, Noriyuki; Okuwaki, Toru; Horiuchi, Akira; Itagaki, Takuma; Niitsu, Mamoru

    2010-01-01

    In scans taken in conventional direction, tracking errors may occur when using a streamline-based algorithm for the tractography of the gastrocnemius muscle. To solve errors in tracking, we applied tractography to the musculotendinous junction and performed fiber tracking on the gastrocnemius muscle of 10 healthy subjects with their written informed consent. We employed a spin-echo diffusion tensor imaging (SE-DTI) sequence with 6-direction diffusion gradient sensitization and acquired DTI images at 1.5 tesla using a body array coil with parallel imaging. We compared tractography obtained in the transverse and sagittal planes using anatomical reference and found that the gastrocnemius muscle and musculotendinous junction were significantly better visualized on sagittal scans and in 3 regions of interest. We utilized Mann-Whitney U-test to determine significant differences between rates of concordance (P 2 value of skeletal muscle is around 50 ms, and TE should be as short as possible. A streamline-based algorithm is based on the continuity of a vector. It is easy to take running of the muscle fiber in sagittal scan. Therefore, tracking error is hard to occur. In conclusion, sagittal scanning may be one way to eliminate tracking errors in the tractography of the gastrocnemius muscle. Tracking errors were smaller with sagittal scans than transverse scans, and sagittal scans allow better fiber tracking. (author)

  12. Fracture resistance of endodontically treated teeth restored with fiber-reinforced composite posts and composite core with varying remaining coronal tooth structure.

    Science.gov (United States)

    Ananviriyaporn, Sirirat; Jitarmat, Piyabhorn; Chairat, Surachara; Ranchan, Atchariyaporn

    2012-01-01

    Endodontically treated teeth often have a varying remaining coronal tooth structure, is an important factor in the successful of post-core with crown restoration. This study compared the fracture resistance of pulpless teeth with variable amounts of remaining coronal tooth structure restored with fiber-reinforced composite posts and composite core. Fifty extracted human premolars were endodontically treated and divided into 5 groups of 10 teeth each. Four groups were prepared having axial wall heights of 4 mm around the preparation circumferences. In 3 of the groups with axial tooth structure, mesial axial tooth structure was removed, mesial and lingual axial tooth structure were removed, mesial-lingual and distal axial tooth structure were removed. For the fifth group, all axial tooth structure was removed to the level of the prepared finish line. All 50 prepared teeth were restored with fiber-reinforced composite posts (FRC Postec Plus) and composite resin cores (Multicore Flow). Testing was conducted with a universal testing machine with the application of a static load to the lingual incline plane of buccal cusp at a crosshead speed of 5 mm/min at 45 degrees to the long axis of the tooth. The load at failure was recorded. The data were subjected to 1-way analysis of variance. The mean value + standard deviation for the failure load of group 1 to 5 were 237.48 +/- 81.87, 242.97 +/- 66.80, 257.67 +/- 70.42, 239.56 +/- 70.42 and 297.70 +/- 99.42 (N), respectively There were no significant differences in the fracture resistance (p structure of endodontically treated tooth had no influenced on the fracture resistance when restored with fiber-reinforced composite posts and composite core.

  13. Electric machines with axial magnetic flux

    Science.gov (United States)

    Nuca, I.; Ambros, T.; Burduniuc, M.; Deaconu, S. I.; Turcanu, A.

    2018-01-01

    The paper contains information on the performance of axial machines compared to cylindrical ones. At the same time, various constructive schemes of synchronous electromechanical converters with permanent magnets and asynchronous with short-circuited rotor are presented. In the developed constructions, the aim is to maximize the usage of the material of the stator windings. The design elements of the axial machine magnetic system are presented. The FEMM application depicted the array of the magnetic field of an axial machine.

  14. Axial vector mass spectrum and mixing angles

    International Nuclear Information System (INIS)

    Caffarelli, R.V.; Kang, K.

    1976-01-01

    Spectral sum rules of the axial-vector current and axial-vector current-pseudoscalar field are used to study the axial-vector mass spectrum and mixing angles, as well as the decay constants and mixing angles of the pseudoscalar mesons. In general, the result is quite persuasive for the existence of the Jsup(PC) = 1 ++ multiplet in which one has a canonical D-E mixing. (Auth.)

  15. Volar morphology of the distal radius in axial planes: a quantitative analysis.

    Science.gov (United States)

    Oura, Keiichiro; Oka, Kunihiro; Kawanishi, Yohei; Sugamoto, Kazuomi; Yoshikawa, Hideki; Murase, Tsuyoshi

    2015-04-01

    To investigate the cause of rupture of the flexor pollicis longus (FPL) after volar plate fixation of distal radius fractures, previous studies have examined the shape of the distal radius in the sagittal plane or in the lateral view. However, there are no reports on the anatomical shape of the volar surface concavity of the distal radius in the axial plane. We hypothesized that this concavity might contribute to the mismatch between the plate and the surface of the radius. To test this hypothesis, we constructed three-dimensional models of the radius and FPL based on computed tomography scans of 70 normal forearms. We analyzed axial cross-sectional views with 2 mm intervals. In all cases, the volar surface of the distal radius was concave in the axial plane. The concavity depth was maximum at 6 mm proximal to the palmar edge of the lunate fossa and progressively decreased toward the proximal radius. FPL was closest to the radius at 2 mm proximal to the palmar edge of the lunate fossa. The volar surface of the distal radius was externally rotated from proximal to distal. These results may help to develop new implants which fit better to the radius and decrease tendon irritation. © 2014 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

  16. Centrifugal and axial compressor control

    CERN Document Server

    McMillan, Gregory K

    2009-01-01

    Control engineers, mechanical engineers and mechanical technicians will learn how to select the proper control systems for axial and centrifugal compressors for proper throughput and surge control, with a particular emphasis on surge control. Readers will learn to understand the importance of transmitter speed, digital controller sample time, and control valve stroking time in helping to prevent surge. Engineers and technicians will find this book to be a highly valuable guide on compressor control schemes and the importance of mitigating costly and sometimes catastrophic surge problems. It can be used as a self-tutorial guide or in the classroom with the book's helpful end-of-chapter questions and exercises and sections for keeping notes.

  17. Axial channeling of uttrarelativistic electrons

    Energy Technology Data Exchange (ETDEWEB)

    Telegin, V.I.; Khokonov, M.Kh. (Moskovskij Gosudarstvennyj Univ. (USSR). Nauchno-Issledovatel' skij Inst. Yadernoj Fiziki)

    1982-07-01

    The dynamics of motion of ultrarelativistic electrons under axial channeling conditions is investigated. The analysis is based on the solution of the kinetic equation obtained recently by Beloshitsky and Kumakhov. The particle dechanneling function is investigated as depending on the type of a crystal, particle energy and angle of entrance into the single crystal. It is found that for most of the beam the major diffusion mechanism is scattering by electrons. It is shown that an optimal depth range exists for which the fraction of channeled particles sharply increases at the expense of the quasi-channeled particles. In a number of cases the dechanneling length for crystals with high atomic numbers may be greater than that of light elements.

  18. Axial channeling of uttrarelativistic electrons

    International Nuclear Information System (INIS)

    Telegin, V.I.; Khokonov, M.Kh.

    1982-01-01

    The dynamics of motion of ultrarelativistic electrons under axial channeling conditions is investigated. The analysis is based on the solution of the kinetic equation obtained recently by Beloshitsky and Kumakhov. The particle dechanneling function is investigated as depending on the type of a crystal, particle energy and angle of entrance into the single crystal. It is found that for most of the beam the major diffusion mechanism is scattering by electrons. It is shown that an optimal depth range exists for which the fraction of channeled particles sharply increases at the expense of the quasi-channeled particles. In a number of cases the dechanneling length for crystals with high atomic numbers may be greater than that of light elements

  19. Radial and axial compression of pure electron

    International Nuclear Information System (INIS)

    Park, Y.; Soga, Y.; Mihara, Y.; Takeda, M.; Kamada, K.

    2013-01-01

    Experimental studies are carried out on compression of the density distribution of a pure electron plasma confined in a Malmberg-Penning Trap in Kanazawa University. More than six times increase of the on-axis density is observed under application of an external rotating electric field that couples to low-order Trivelpiece-Gould modes. Axial compression of the density distribution with the axial length of a factor of two is achieved by controlling the confining potential at both ends of the plasma. Substantial increase of the axial kinetic energy is observed during the axial compression. (author)

  20. Axial and Radial Oxylipin Transport.

    Science.gov (United States)

    Gasperini, Debora; Chauvin, Adeline; Acosta, Ivan F; Kurenda, Andrzej; Stolz, Stéphanie; Chételat, Aurore; Wolfender, Jean-Luc; Farmer, Edward E

    2015-11-01

    Jasmonates are oxygenated lipids (oxylipins) that control defense gene expression in response to cell damage in plants. How mobile are these potent mediators within tissues? Exploiting a series of 13-lipoxygenase (13-lox) mutants in Arabidopsis (Arabidopsis thaliana) that displays impaired jasmonic acid (JA) synthesis in specific cell types and using JA-inducible reporters, we mapped the extent of the transport of endogenous jasmonates across the plant vegetative growth phase. In seedlings, we found that jasmonate (or JA precursors) could translocate axially from wounded shoots to unwounded roots in a LOX2-dependent manner. Grafting experiments with the wild type and JA-deficient mutants confirmed shoot-to-root oxylipin transport. Next, we used rosettes to investigate radial cell-to-cell transport of jasmonates. After finding that the LOX6 protein localized to xylem contact cells was not wound inducible, we used the lox234 triple mutant to genetically isolate LOX6 as the only JA precursor-producing LOX in the plant. When a leaf of this mutant was wounded, the JA reporter gene was expressed in distal leaves. Leaf sectioning showed that JA reporter expression extended from contact cells throughout the vascular bundle and into extravascular cells, revealing a radial movement of jasmonates. Our results add a crucial element to a growing picture of how the distal wound response is regulated in rosettes, showing that both axial (shoot-to-root) and radial (cell-to-cell) transport of oxylipins plays a major role in the wound response. The strategies developed herein provide unique tools with which to identify intercellular jasmonate transport routes. © 2015 American Society of Plant Biologists. All Rights Reserved.

  1. A Survey of Coronal Heating Properties in Solar Active Regions

    Science.gov (United States)

    Viall, Nicholeen; Klimchuk, James A.

    2014-06-01

    We investigate the properties of coronal heating in solar active regions (AR) by systematically analyzing coronal light curves observed by the Atmospheric Imaging Assembly onboard the Solar Dynamics Observatory. Our automated technique computes time-lags (cooling times) on a pixel-by-pixel basis, and has the advantage that it allows us to analyze all of the coronal AR emission, including the so-called diffuse emission between coronal loops. We recently presented results using this time-lag analysis on NOAA AR 11082 (Viall & Klimchuk 2012) and found that the majority of the pixels contained cooling plasma along their line of sight. This result is consistent with impulsive coronal nanoflare heating of both coronal loops and the surrounding diffuse emission in the AR. Here we present the results of our time-lag technique applied to a survey of 15 AR of different magnetic complexity, total unsigned magnetic flux, size and age. We show that the post-nanoflare cooling patterns identified in NOAA AR 11082 are identified throughout all of the active regions in this survey, indicating that nanoflare heating is ubiquitous in solar active regions. However, some details of the nanoflare properties, such as the nanoflare energy, are different across these different active regions.We thank the SDO/AIA team for the use of these data, and the Coronal Heating ISSI team for helpful discussion of these topics. This research was supported by a NASA Heliophysics GI.

  2. Measurements of EUV coronal holes and open magnetic flux

    International Nuclear Information System (INIS)

    Lowder, C.; Qiu, J.; Leamon, R.; Liu, Y.

    2014-01-01

    Coronal holes are regions on the Sun's surface that map the footprints of open magnetic field lines. We have developed an automated routine to detect and track boundaries of long-lived coronal holes using full-disk extreme-ultraviolet (EUV) images obtained by SOHO/EIT, SDO/AIA, and STEREO/EUVI. We measure coronal hole areas and magnetic flux in these holes, and compare the measurements with calculations by the potential field source surface (PFSS) model. It is shown that, from 1996 through 2010, the total area of coronal holes measured with EIT images varies between 5% and 17% of the total solar surface area, and the total unsigned open flux varies between (2-5)× 10 22 Mx. The solar cycle dependence of these measurements is similar to the PFSS results, but the model yields larger hole areas and greater open flux than observed by EIT. The AIA/EUVI measurements from 2010-2013 show coronal hole area coverage of 5%-10% of the total surface area, with significant contribution from low latitudes, which is under-represented by EIT. AIA/EUVI have measured much enhanced open magnetic flux in the range of (2-4)× 10 22 Mx, which is about twice the flux measured by EIT, and matches with the PFSS calculated open flux, with discrepancies in the location and strength of coronal holes. A detailed comparison between the three measurements (by EIT, AIA-EUVI, and PFSS) indicates that coronal holes in low latitudes contribute significantly to the total open magnetic flux. These low-latitude coronal holes are not well measured with either the He I 10830 line in previous studies, or EIT EUV images; neither are they well captured by the static PFSS model. The enhanced observations from AIA/EUVI allow a more accurate measure of these low-latitude coronal holes and their contribution to open magnetic flux.

  3. Heating of solar coronal holes by reflected Alfven waves

    Science.gov (United States)

    Moore, R. L.; Musielak, Z. E.; Suess, S. T.; An, C.-H.

    1992-01-01

    As a continuation of the work of Moore et al. (1991), who found evidence that coronal holes are heated by Alfven waves that are reflected back down within the coronal holes, this paper shows that to demonstrate this evidence, it is only necessary to consider a subset of the Moore et al. models, namely, those having radial magnetic field. Using these models, it is shown that the Alfven velocity is not constant in the atmosphere of coronal holes, but changes with height (or radius), causing downward reflection of all upward Alfven waves of sufficiently long wavelength (or period).

  4. Case report: pre-eruptive intra-coronal radiolucencies revisited.

    LENUS (Irish Health Repository)

    Counihan, K P

    2012-08-01

    Pre-eruptive intra-coronal radiolucency (PEIR) describes a radiolucent lesion located in the coronal dentine, just beneath the enamel-dentine junction of unerupted teeth. The prevalence of this lesion varies depending on the type and quality of radiographic exposure and age of patients used for assessment. The aetiology of pre-eruptive intra-coronal radiolucent lesions is not fully understood, but published clinical and histological evidence suggest that these lesions are resorptive in nature. Issues around the diagnosis, treatment planning and clinical management of this lesion are explored using previously unreported cases.

  5. Magnetohydrodynamic waves and coronal seismology: an overview of recent results.

    Science.gov (United States)

    De Moortel, Ineke; Nakariakov, Valery M

    2012-07-13

    Recent observations have revealed that magnetohydrodynamic (MHD) waves and oscillations are ubiquitous in the solar atmosphere, with a wide range of periods. We give a brief review of some aspects of MHD waves and coronal seismology that have recently been the focus of intense debate or are newly emerging. In particular, we focus on four topics: (i) the current controversy surrounding propagating intensity perturbations along coronal loops, (ii) the interpretation of propagating transverse loop oscillations, (iii) the ongoing search for coronal (torsional) Alfvén waves, and (iv) the rapidly developing topic of quasi-periodic pulsations in solar flares.

  6. Utility of coronal oblique slices in cervical spine MRI. Improved detection of the neuroforamina; Nutzen der halbkoronaren Schichtung im MRT der Halswirbelsaeule. Verbesserte Erkennbarkeit von Neuroforamina

    Energy Technology Data Exchange (ETDEWEB)

    Freund, W.; Hoepner, G. [Universitaetskliniken Ulm, Klinik fuer Diagnostische und Interventionelle Radiologie, Ulm (Germany); Klessinger, S. [Nova Clinic Biberach, Neurochirurgie, Biberach (Germany); Universitaetskliniken Ulm, Neurochirurgie, Ulm (Germany); Mueller, M. [Universitaetskliniken Ulm, Klinik fuer Diagnostische und Interventionelle Radiologie, Ulm (Germany); Universitaetskliniken Aachen, Diagnostische und Interventionelle Neuroradiologie, Aachen (Germany); Halatsch, M.E. [Universitaetskliniken Ulm, Neurochirurgie, Ulm (Germany); Weber, F. [Bundeswehrkrankenhaus Ulm, Neurologie, Ulm (Germany); Schmitz, B. [Universitaetskliniken Ulm, Neuroradiologie, Ulm (Germany)

    2015-11-15

    Angulated projections are standard in conventional radiography of the cervical spine, but rarely used in magnetic resonance imaging (MRI). As neuroforaminal pathology plays an important role in the etiology of radicular syndromes and may influence an operative approach, the utility of coronal oblique slices in MRI is explored. In a retrospective setting, 25 consecutive patients with neurologically diagnosed cervical monoradiculopathy were identified. T2-weighted sagittal, coronal oblique, and transversal slice orientations were anonymized. Two radiologists and two neurosurgeons independently assessed the cases. Criteria were site, cause, and grading of the neuroforaminal stenosis and the level of confidence on a 100-point visual analog scale (VAS). We computed interrater agreement, sensitivity, and t tests. Using only one slice orientation, the sensitivity in detecting the relevant neuroforamen was 0.40 for transversal, 0.68 for sagittal, and 0.64 for coronal oblique scans. A combination of the different angulations increased sensitivity and in 4 cases only the coronal oblique scans proved diagnostic. The readers felt significantly more confident in attributing the cause of the pathology on coronal oblique planes (a mean of 72 VAS points, p = 0.0003 vs 58 (sagittal) vs 64 (transversal)). Interrater agreement was significantly better for experienced (kappa 0. 48) than for inexperienced readers (0.32, p = 0.02). Adding coronal oblique planes in cervical spine MRI increases sensitivity and confidence in attributing the cause of neuroforaminal pathology. They are regarded as useful by all the readers. (orig.) [German] Im Gegensatz zur Magnetresonanztomographie (MRT) sind in der konventionellen Roentgendiagnostik der Halswirbelsaeule (HWS) Schraegaufnahmen Standard. Da neuroforaminale Pathologien wichtige Ursachen von radikulaeren Syndromen sind und die Operationstechnik moeglicherweise beeinflussen, wird der Nutzen halbkoronarer Schichten in der MRT untersucht. In

  7. [Correlation between sagittal photogrammetric measurements of the soft tissue profile and dental arches measurements].

    Science.gov (United States)

    Diouf, Joseph Samba; Touré, Bécaye; Ndiaye, Marième; Badiane, Alpha; Diop-Bâ, Khady; Ngom, Papa Ibrahima; Diagne, Falou

    2015-12-01

    Sagittal soft-tissue analyses made from photographic records (sagittal photogrammetric analysis of the soft tissues) allow orthodontists to quantify the sagittal dimension and situation of the facial soft tissues. These tissues maintain close anatomical relationships with the underlying dental arches. However, little importance has been given to the description and the comparison of the sagittal soft tissue morphology according to dental arches parameters. The purpose of this study was to determine the correlation between the sagittal photogrammetric soft tissue profile and the dental arches measurements. A cross-sectional study was performed in a group of students. Standardized facial-profile photographs were taken with each student in natural head position, and relaxed lip posture. Photogrammetric parameters were measured on paper sheet using a graduated ruler. Dental arches measurements were also performed directly into the mouth with an electronic caliper. The strength of the association between sagittal photogrammetric soft tissue measurements and dental arches parameters was investigated by a Pearson's correlation. Results were regarded as significant at p=0.05. The lips protrusion parameters were significantly and positively correlated with the dental arch lengths. The overjet was significantly and positively correlated with Ls/Sn-Sm. The overbite was significantly and negatively correlated with the sagittal labial parameters Ls/N-Ort, Li/N-Ort, Ls-E, Li E, Ls-S, Li S, Ls/Sn-Sm and Li/Sn-Sm. The correlations found in this study show the importance of taking into account the soft tissue in the diagnosis and orthodontic treatment of patients. © EDP Sciences, SFODF, 2015.

  8. Health and imaging outcomes in axial spondyloarthritis

    NARCIS (Netherlands)

    Machado, P.M.

    2016-01-01

    This thesis focuses on the assessment and monitoring of health and imaging outcomes in axial spondyloarthritis (SpA) and the relationship between these outcomes. Four major contributions to the understanding and management of axial SpA were made: 1) the improvement and facilitation of the assessment

  9. Aryabhata and Axial Rotation of Earth

    Indian Academy of Sciences (India)

    GENERAL I ARTICLE. Aryabhata and Axial Rotation of Earth. 3. A Brief History. Amartya Kumar Datta is in the Stat-Math Unit of. Indian Statistic.llnstiutte,. Kolkata. His research ... historical account of some of Aryabha~a's views on axial rotation of Earth, ..... and stress on periodic observations and updating of the parameters.

  10. Coronal Dynamics at Recent Total Solar Eclipses

    Science.gov (United States)

    Pasachoff, J. M.; Lu, M.; Davis, A. B.; Demianski, M.; Rusin, V.; Saniga, M.; Seaton, D. B.; Lucas, R.; Babcock, B. A.; Dantowitz, R.; Gaintatzis, P.; Seeger, C. H.; Malamut, C.; Steele, A.

    2014-12-01

    Our composite images of the solar corona based on extensive imaging at the total solar eclipses of 2010 (Easter Island), 2012 (Australia), and 2013 (Gabon) reveal several coronal mass ejections and other changes in coronal streamers and in polar plumes. Our resultant spatial resolution is finer than that available in imaging from spacecraft, including that from SOHO/LASCO or STEREO. We trace the eruptions back to their footpoints on the sun using imaging from SDO and SWAP, and follow them upwards through the corona, measuring velocities. The high-resolution computer compositing by Miloslav Druckmüller and Hana Druckmüllerová (2010 and 2013) and Pavlos Gaintatzis (2012) allows comparison of our images with those taken at intervals of minutes or hours along the totality path. Williams College's 2013 eclipse expedition was supported in part by grant 9327-13 from National Geographic Society/Committee for Research and Exploration. Our work on the 2012 eclipse is supported in part by grant AGS-1047726 from Solar Terrestrial Research/NSF AGS. V.R. and M.S. were partially supported by the VEGA grant agency project 2/0098/10 and 2/0003/13 (Slovak Academy of Sciences) and Grant 0139-12 from NG/CRE, and Hana Druckmüllerová by grant 205/09/1469 of the Czech Science Foundation. M.L. was supported by Sigma Xi. C.M. was a Keck Northeast Astronomy Consortium Summer Fellow, supported at Williams College by REU/NSF grant AST-1005024. Partial support was provided by U.S. Department of Defense's ASSURE program. J.M.P. thanks Caltech's Planetary Sciences Department for hospitality. Support for D.B.S. and SWAP came from PRODEX grant C90345 managed by ESA in collaboration with the Belgian Federal Science Policy Office (BELSPO) in support of the PROBA2/SWAP mission, and from the EC's Seventh Framework Programme (FP7/2007-2013) under grant 218816 (SOTERIA project, www.soteria-space.eu). SWAP is a project of the Centre Spatial de Liège and the Royal Observatory of Belgium funded by

  11. Coroner Autopsy Findings Among Children and Adolescents of ...

    African Journals Online (AJOL)

    year retrospective study of coroner autopsies carried out on children I adolescents aged between 0-19 years, evaluated the pattern, causes and demographic features of childhood deaths in Rivers state, Nigeria. Methods A retrospective remew of ...

  12. Coronal CT imaging of the extremity growth plate

    International Nuclear Information System (INIS)

    Murray, K.; Nixon, G.W.

    1986-01-01

    Coronal CT imaging has been used to evaluate the growth plate region of long bones. Proper patient positioning facilitates coronal imaging and is easily achieved in most instances. Studied were neoplasms, instances of partial growth arrest, and loose bodies. In the evaluation of neoplasms and neoplasia, coronal sections are most useful in determining the longitudinal extent of disease and involvement of the growth plate and epiphysis. This information is useful in diagnosis and is of critical importance in operative planning. Coronal CT imaging also allows determination of the location and extent of involvement of partial growth plate arrest after physeal injury. This method of growth plate mapping gives information superior to the obtained from conventional or reconstructed CT images

  13. The nature of micro CMEs within coronal holes

    Science.gov (United States)

    Bothmer, Volker; Nistico, Giuseppe; Zimbardo, Gaetano; Patsourakos, Spiros; Bosman, Eckhard

    Whilst investigating the origin and characteristics of coronal jets and large-scale CMEs identi-fied in data from the SECCHI (Sun Earth Connection Coronal and Heliospheric Investigation) instrument suites on board the two STEREO satellites, we discovered transient events that originated in the low corona with a morphology resembling that of typical three-part struc-tured coronal mass ejections (CMEs). However, the CMEs occurred on considerably smaller spatial scales. In this presentation we show evidence for the existence of small-scale CMEs from inside coronal holes and present quantitative estimates of their speeds and masses. We interprete the origin and evolution of micro CMEs as a natural consequence of the emergence of small-scale magnetic bipoles related to the Sun's ever changing photospheric magnetic flux on various scales and their interactions with the ambient plasma and magnetic field. The analysis of CMEs is performed within the framework of the EU Erasmus and FP7 SOTERIA projects.

  14. LONG-TERM TREND OF SOLAR CORONAL HOLE DISTRIBUTION FROM 1975 TO 2014

    Energy Technology Data Exchange (ETDEWEB)

    Fujiki, K.; Tokumaru, M.; Hayashi, K.; Satonaka, D. [Institute for Space-Earth Environmental Research (ISEE), Nagoya University, Furo-cho, Chikusa, Nagoya Aichi 464-8601 (Japan); Hakamada, K., E-mail: fujiki@isee.nagoya-u.ac.jp [Department of Natural Science and Mathematics, Chubu University, 1200 Matsumoto-cho, Kasugai, Aichi 487-8501 (Japan)

    2016-08-20

    We developed an automated prediction technique for coronal holes using potential magnetic field extrapolation in the solar corona to construct a database of coronal holes appearing from 1975 February to 2015 July (Carrington rotations from 1625 to 2165). Coronal holes are labeled with the location, size, and average magnetic field of each coronal hole on the photosphere and source surface. As a result, we identified 3335 coronal holes and found that the long-term distribution of coronal holes shows a similar pattern known as the magnetic butterfly diagram, and polar/low-latitude coronal holes tend to decrease/increase in the last solar minimum relative to the previous two minima.

  15. Sagittal alignment as a predictor of clinical adjacent segment pathology requiring surgery after anterior cervical arthrodesis.

    Science.gov (United States)

    Park, Moon Soo; Kelly, Michael P; Lee, Dong-Ho; Min, Woo-Kie; Rahman, Ra'Kerry K; Riew, K Daniel

    2014-07-01

    Postoperative malalignment of the cervical spine may alter cervical spine mechanics and put patients at risk for clinical adjacent segment pathology requiring surgery. To investigate whether a relationship exists between cervical spine sagittal alignment and clinical adjacent segment pathology requiring surgery (CASP-S) following anterior cervical fusion (ACF). Retrospective matched study. A total of 122 patients undergoing ACF between 1996 and 2008 were identified, with a minimum of 2 years of follow-up. Radiographs were reviewed to measure the sagittal alignment using C2 and C7 sagittal plumb lines, distance from the fusion mass plumb line to the C2 and C7 plumb lines, the alignment of the fusion mass, caudally adjacent disc angle, the sagittal slope angle of the superior end plate of the vertebra caudally adjacent to the fusion mass, T1 sagittal angle, overall cervical sagittal alignment, and curve patterns by Katsuura classification. A total of 122 patients undergoing ACF between 1996 and 2008 were identified, with a minimum of 1 year of follow-up. Patients were divided into groups according to the development of CASP (control/CASP-S) and by number/location of levels fused. Radiographs were reviewed to measure the sagittal alignment using C2 and C7 sagittal plumb lines, distance from the fusion mass plumb line to the C2 and C7 plumb lines, the alignment of the fusion mass, caudally adjacent disc angle, the sagittal slope angle of the superior end plate of the vertebra caudally adjacent to the fusion mass, T1 sagittal angle, overall cervical sagittal alignment, and curve patterns by Katsuura classification. Appropriate statistical tests were performed to calculate relationships between the variables and the development of CASP-S. No funds were received in support of this work. No benefits in any form have been or will be received from a commercial party related directly or indirectly to the subject of this article. The groups were similar with regard to

  16. Effect of one- or two-level posterior lumbar interbody fusion on global sagittal balance.

    Science.gov (United States)

    Cho, Jae Hwan; Joo, Youn-Suk; Lim, Cheongsu; Hwang, Chang Ju; Lee, Dong-Ho; Lee, Choon Sung

    2017-12-01

    Sagittal imbalance is associated with poor clinical outcomes in patients with degenerative lumbar disease. However, there is no consensus on the impact of posterior lumbar interbody fusion (PLIF) on local and global sagittal balance. To reveal the effect of one- or two-level PLIF on global sagittal balance. A retrospective case-control study. This study included 88 patients who underwent a one- or two-level PLIF for spinal stenosis with spondylolisthesis. Clinical and radiological parameters were measured pre- and postoperatively. All patients were followed up for >2 years. Clinical outcomes included a visual analog scale, Oswestry Disability Index, and EuroQol 5-dimension questionnaire (EQ-5D). Radiological parameters were measured using whole-spine standing lateral radiographs. Fusion, loosening, subsidence rates, and adverse events were also evaluated. Patients were divided into two groups according to their preoperative C7-S1 sagittal vertical axis (SVA): Group N: SVA≤5 cm vs Group I: SVA>5 cm; they were also divided according to postoperative changes in C7-S1 SVA. Clinical and radiological outcomes were compared between the groups. All clinical outcomes and radiological parameters improved postoperatively. C7-S1 SVA improved (-1.6 cm) after L3-L5 fusion, but it was compromised (+3.6 cm) after L4-S1 fusion (p=.001). Preoperative demographic and clinical data showed no difference except in the anxiety or depression domain of EQ-5D. No differences were found in postoperative clinical outcomes. Lumbar lordosis, pelvic tilt, and thoracic kyphosis slightly improved in Group N, whereas C7-S1 SVA decreased from 9.5 cm to 3.8 cm (pfusion (L3-L5 vs L4-S1, p=.033). Global sagittal balance improved after short-level lumbar fusion surgery in patients having spinal stenosis with spondylolisthesis who showed preoperative sagittal imbalance. Restoration of sagittal balance predominantly occurred after L3-L4, L4-L5, or L3-L5 PLIF. However, no such restoration was

  17. Axial anomalies of Lifshitz fermions

    CERN Document Server

    Bakas, Ioannis

    2011-01-01

    We compute the axial anomaly of a Lifshitz fermion theory with anisotropic scaling z=3 which is minimally coupled to geometry in 3+1 space-time dimensions. We find that the result is identical to the relativistic case using path integral methods. An independent verification is provided by showing with spectral methods that the eta-invariant of the Dirac and Lifshitz fermion operators in three dimensions are equal. Thus, by the integrated form of the anomaly, the index of the Dirac operator still accounts for the possible breakdown of chiral symmetry in non-relativistic theories of gravity. We apply this framework to the recently constructed gravitational instanton backgrounds of Horava-Lifshitz theory and find that the index is non-zero provided that the space-time foliation admits leaves with harmonic spinors. Using Hitchin's construction of harmonic spinors on Berger spheres, we obtain explicit results for the index of the fermion operator on all such gravitational instanton backgrounds with SU(2)xU(1) isom...

  18. MHD Simulations of the Eruption of Coronal Flux Ropes under Coronal Streamers

    Science.gov (United States)

    Fan, Yuhong

    2017-07-01

    Using three-dimensional magnetohydrodynamic (MHD) simulations, we investigate the eruption of coronal flux ropes underlying coronal streamers and the development of a prominence eruption. We initialize a quasi-steady solution of a coronal helmet streamer, into which we impose at the lower boundary the slow emergence of a part of a twisted magnetic torus. As a result, a quasi-equilibrium flux rope is built up under the streamer. With varying streamer sizes and different lengths and total twists of the flux rope that emerges, we found different scenarios for the evolution from quasi-equilibrium to eruption. In the cases with a broad streamer, the flux rope remains well confined until there is sufficient twist such that it first develops the kink instability and evolves through a sequence of kinked, confined states with increasing height until it eventually develops a “hernia-like” ejective eruption. For significantly twisted flux ropes, prominence condensations form in the dips of the twisted field lines due to runaway radiative cooling. Once formed, the prominence-carrying field becomes significantly non-force-free due to the weight of the prominence, despite having low plasma β. As the flux rope erupts, the prominence erupts, showing substantial draining along the legs of the erupting flux rope. The prominence may not show a kinked morphology even though the flux rope becomes kinked. On the other hand, in the case with a narrow streamer, the flux rope with less than one wind of twist can erupt via the onset of the torus instability.

  19. MHD Simulations of the Eruption of Coronal Flux Ropes under Coronal Streamers

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Yuhong, E-mail: yfan@ucar.edu [High Altitude Observatory, National Center for Atmospheric Research, 3080 Center Green Drive, Boulder, CO 80301 (United States)

    2017-07-20

    Using three-dimensional magnetohydrodynamic (MHD) simulations, we investigate the eruption of coronal flux ropes underlying coronal streamers and the development of a prominence eruption. We initialize a quasi-steady solution of a coronal helmet streamer, into which we impose at the lower boundary the slow emergence of a part of a twisted magnetic torus. As a result, a quasi-equilibrium flux rope is built up under the streamer. With varying streamer sizes and different lengths and total twists of the flux rope that emerges, we found different scenarios for the evolution from quasi-equilibrium to eruption. In the cases with a broad streamer, the flux rope remains well confined until there is sufficient twist such that it first develops the kink instability and evolves through a sequence of kinked, confined states with increasing height until it eventually develops a “hernia-like” ejective eruption. For significantly twisted flux ropes, prominence condensations form in the dips of the twisted field lines due to runaway radiative cooling. Once formed, the prominence-carrying field becomes significantly non-force-free due to the weight of the prominence, despite having low plasma β . As the flux rope erupts, the prominence erupts, showing substantial draining along the legs of the erupting flux rope. The prominence may not show a kinked morphology even though the flux rope becomes kinked. On the other hand, in the case with a narrow streamer, the flux rope with less than one wind of twist can erupt via the onset of the torus instability.

  20. Coroner consistency - The 10-jurisdiction, 10-year, postcode lottery?

    Science.gov (United States)

    Mclean, Maxwell

    2015-04-01

    The investigation and classification of deaths in England and Wales relies upon the application by medical practitioners of diverse reporting standards set locally by coroners and thereafter upon the effectively unconstrained decision process of those same coroners. The author has conducted extensive comparative analysis of Ministry of Justice data on reports to the coroner and their inquest and verdict returns alongside Office of National Statistics data pertaining to the numbers of registered deaths in equivalent local jurisdictions. Here, he analyses 10 jurisdictions characterised by almost identical inquest return numbers in 2011. Substantial variation was found in reporting rates to the coroner and in the profile of inquest verdicts. The range of deaths reported varied from 34% to 62% of all registered deaths. Likewise only 2 of the 10 jurisdictions shared the same ranking of proportions in which the six common verdicts were reached. Individual jurisdictions tended to be consistent over time in their use of verdicts. In all cases, proportionately more male deaths were reported to the coroner. Coroners generally seemed prima facie to be 'gendered' in their approach to verdicts; that is, they were consistently more likely to favour a particular verdict when dealing with a death, according to the sex of the deceased. The extent to which coroners seemed gendered varied widely. While similar services such as the criminal courts or the Crown Prosecution Service are subject to extensive national guidance in an attempt to constrain idiosyncratic decision making, there seems no reason why this should apply less to the process of death investigation and classification. Further analysis of coroners' local practices and their determinants seems necessary. © International Headache Society 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  1. Postoperative change in sagittal balance after Kyphoplasty for the treatment of osteoporotic vertebral compression fracture.

    Science.gov (United States)

    Yokoyama, Kunio; Kawanishi, Masahiro; Yamada, Makoto; Tanaka, Hidekazu; Ito, Yutaka; Kawabata, Shinji; Kuroiwa, Toshihiko

    2015-04-01

    The influence of vertebral cement augmentation on spinal sagittal balance is unknown. The present study aimed to analyze the changes in total spinal alignment after Kyphoplasty in VCF patients. The study involved 21 VCF patients who underwent Kyphoplasty. In all patients, lateral radiographs of the entire spine were taken preoperatively and 1 month after surgery, to measure the pelvic incidence (PI), sacral slope (SS), pelvic tilt (PT), lumbar lordosis (LL), sagittal vertical axis (SVA), and spinosacral angle (SSA). These parameters were compared between VCF patients and 30 healthy volunteers. In VCF patients, the parameters were compared before and after Kyphoplasty. In VCF patients, preoperative SVA was 7.00 ± 3.9 cm, showing a significant shift to anterior sagittal balance as compared to the healthy group (1.45 ± 2.7 cm) (P vertebra (r = 0.792, P < 0.01). VAS score decreased from 7.98 ± 1.8 before Kyphoplasty to 2.38 ± 2.3 postoperatively (P < 0.0001). Total spinal alignment is shifted to anterior sagittal balance in VCF patients. Kyphoplasty plays a role not only in reducing pain associated with fractures but also in improving sagittal imbalance in the treatment of painful vertebral compression fracture.

  2. A Catalog of Coronal "EIT Wave" Transients

    Science.gov (United States)

    Thompson, B. J.; Myers, D. C.

    2009-01-01

    Solar and Heliospheric Observatory (SOHO) Extreme ultraviolet Imaging Telescope (EIT) data have been visually searched for coronal "EIT wave" transients over the period beginning from 1997 March 24 and extending through 1998 June 24. The dates covered start at the beginning of regular high-cadence (more than one image every 20 minutes) observations, ending at the four-month interruption of SOHO observations in mid-1998. One hundred and seventy six events are included in this catalog. The observations range from "candidate" events, which were either weak or had insufficient data coverage, to events which were well defined and were clearly distinguishable in the data. Included in the catalog are times of the EIT images in which the events are observed, diagrams indicating the observed locations of the wave fronts and associated active regions, and the speeds of the wave fronts. The measured speeds of the wave fronts varied from less than 50 to over 700 km s(exp -1) with "typical" speeds of 200-400 km s(exp -1).

  3. TRANSVERSE OSCILLATIONS OF SYSTEMS OF CORONAL LOOPS

    International Nuclear Information System (INIS)

    Luna, M.; Oliver, R.; Ballester, J. L.; Terradas, J.

    2009-01-01

    We study the collective kinklike normal modes of a system of several cylindrical loops using the T-matrix theory. Loops that have similar kink frequencies oscillate collectively with a frequency which is slightly different from that of the individual kink mode. On the other hand, if the kink frequency of a loop is different from that of the others, it oscillates individually with its own frequency. Since the individual kink frequency depends on the loop density but not on its radius for typical 1 MK coronal loops, a coupling between kink oscillations of neighboring loops takes place when they have similar densities. The relevance of these results in the interpretation of the oscillations studied by Schrijver and Brown in 2000 and Verwichte et al. in 2004, in which transverse collective loop oscillations seem to be detected, is discussed. In the first case, two loops oscillating in antiphase are observed; interpreting this motion as a collective kink mode suggests that their densities are roughly equal. In the second case, there are almost three groups of tubes that oscillate with similar periods, and therefore their dynamics can be collective, which again seems to indicate that the loops of each group share a similar density. All the other loops seem to oscillate individually and their densities can be different from the rest.

  4. Coronal microleakage assessed by polymicrobial markers.

    Science.gov (United States)

    Britto, Leandro Rodrigues; Grimaudo, Nicholas J; Vertucci, Frank J

    2003-08-15

    Studies have shown significant bacterial leakage following exposure of sealed root canals to artificial and natural saliva. The objective of this study was to determine contamination via bacterial migration in artificial saliva in endodontically treated teeth using different obturation techniques and sealers. A total of 144 extracted, human mandibular anterior teeth were cleaned and shaped to a #40 master apical file using hand and rotary instrumentation. One hundred and twenty teeth were divided into two experimental groups. The teeth in Group 1 were obturated with gutta-percha using lateral compaction and five different sealers, and the teeth in Group 2 were obturated with gutta-percha using thermomechanical compaction and five different sealers. The remaining 24 teeth were prepared as positive and negative controls. All specimens, except the negative controls, were inoculated every five days with Anaerobic streptococci (NCTC 9891) related to Peptostreptococcus micros and Prevotella intermedia (ATCC 25611). The contamination onset time was continuously recorded and turbid broths cultured for bacteria identification. The controls behaved as expected. Regardless of the combination between obturation techniques and different sealers, all broths became turbid during this experiment. The correlation between the obturation techniques and the sealers revealed statistical significance using ANOVA (psealer allowed a slower rate of coronal-apical bacterial migration.

  5. Active Longitude and Coronal Mass Ejection Occurrences

    Energy Technology Data Exchange (ETDEWEB)

    Gyenge, N.; Kiss, T. S.; Erdélyi, R. [Solar Physics and Space Plasmas Research Centre (SP2RC), School of Mathematics and Statistics, University of Sheffield Hounsfield Road, Hicks Building, Sheffield S3 7RH (United Kingdom); Singh, T.; Srivastava, A. K., E-mail: n.g.gyenge@sheffield.ac.uk [Department of Physics, Indian Institute of Technology (Banaras Hindu University), Varanasi (India)

    2017-03-20

    The spatial inhomogeneity of the distribution of coronal mass ejection (CME) occurrences in the solar atmosphere could provide a tool to estimate the longitudinal position of the most probable CME-capable active regions in the Sun. The anomaly in the longitudinal distribution of active regions themselves is often referred to as active longitude (AL). In order to reveal the connection between the AL and CME spatial occurrences, here we investigate the morphological properties of active regions. The first morphological property studied is the separateness parameter, which is able to characterize the probability of the occurrence of an energetic event, such as a solar flare or CME. The second morphological property is the sunspot tilt angle. The tilt angle of sunspot groups allows us to estimate the helicity of active regions. The increased helicity leads to a more complex buildup of the magnetic structure and also can cause CME eruption. We found that the most complex active regions appear near the AL and that the AL itself is associated with the most tilted active regions. Therefore, the number of CME occurrences is higher within the AL. The origin of the fast CMEs is also found to be associated with this region. We concluded that the source of the most probably CME-capable active regions is at the AL. By applying this method, we can potentially forecast a flare and/or CME source several Carrington rotations in advance. This finding also provides new information for solar dynamo modeling.

  6. Geometric Model of a Coronal Cavity

    Science.gov (United States)

    Kucera, Therese A.; Gibson, S. E.; Ratawicki, D.; Dove, J.; deToma, G.; Hao, J.; Hudson, H. S.; Marque, C.; McIntosh, P. S.; Reeves, K. K.; hide

    2010-01-01

    We observed a coronal cavity from August 8-18 2007 during a multi-instrument observing campaign organized under the auspices of the International Heliophysical Year (IHY). Here we present initial efforts to model the cavity with a geometrical streamer-cavity model. The model is based the white-light streamer mode] of Gibson et a]. (2003 ), which has been enhanced by the addition of a cavity and the capability to model EUV and X-ray emission. The cavity is modeled with an elliptical cross-section and Gaussian fall-off in length and width inside the streamer. Density and temperature can be varied in the streamer and cavity and constrained via comparison with data. Although this model is purely morphological, it allows for three-dimensional, multi-temperature analysis and characterization of the data, which can then provide constraints for future physical modeling. Initial comparisons to STEREO/EUVI images of the cavity and streamer show that the model can provide a good fit to the data. This work is part of the effort of the International Space Science Institute International Team on Prominence Cavities

  7. Guided flows in coronal magnetic flux tubes

    Science.gov (United States)

    Petralia, A.; Reale, F.; Testa, P.

    2018-01-01

    Context. There is evidence that coronal plasma flows break down into fragments and become laminar. Aims: We investigate this effect by modelling flows confined along magnetic channels. Methods: We consider a full magnetohydrodynamic (MHD) model of a solar atmosphere box with a dipole magnetic field. We compare the propagation of a cylindrical flow perfectly aligned with the field to that of another flow with a slight misalignment. We assume a flow speed of 200 km s-1 and an ambient magnetic field of 30 G. Results: We find that although the aligned flow maintains its cylindrical symmetry while it travels along the magnetic tube, the misaligned one is rapidly squashed on one side, becoming laminar and eventually fragmented because of the interaction and back-reaction of the magnetic field. This model could explain an observation made by the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory of erupted fragments that fall back onto the solar surface as thin and elongated strands and end up in a hedge-like configuration. Conclusions: The initial alignment of plasma flow plays an important role in determining the possible laminar structure and fragmentation of flows while they travel along magnetic channels. Movies are available in electronic form at http://www.aanda.org

  8. Evidence linking coronal mass ejections with interplanetary magnetic clouds

    International Nuclear Information System (INIS)

    Wilson, R.M.; Hildner, E.

    1983-12-01

    Using proxy data for the occurrence of those mass ejections from the solar corona which are directed earthward, we investigate the association between the post-1970 interplanetary magnetic clouds of Klein and Burlaga and coronal mass ejections. The evidence linking magnetic clouds following shocks with coronal mass ejections is striking. Six of nine clouds observed at Earth were preceded an appropriate time earlier by meter-wave type II radio bursts indicative of coronal shock waves and coronal mass ejections occurring near central meridian. During the selected periods when no clouds were detected near Earth, the only type II bursts reported were associated with solar activity near the limbs. Where the proxy solar data to be sought are not so clearly suggested, that is, for clouds preceding interaction regions and clouds within cold magnetic enhancements, the evidence linking the clouds and coronal mass ejections is not as clear proxy data usually suggest many candidate mass-ejection events for each cloud. Overall, the data are consistent with and support the hypothesis suggested by Klein and Burlaga that magnetic clouds observed with spacecraft at 1 AU are manifestations of solar coronal mass ejection transients

  9. New Evidence that Magnetoconvection Drives Solar–Stellar Coronal Heating

    Energy Technology Data Exchange (ETDEWEB)

    Tiwari, Sanjiv K.; Panesar, Navdeep K.; Moore, Ronald L.; Winebarger, Amy R. [NASA Marshall Space Flight Center, Mail Code ST 13, Huntsville, AL 35812 (United States); Thalmann, Julia K., E-mail: sanjivtiwari80@gmail.com [Institute of Physics/IGAM, University of Graz, Universittsplatz 5/II, A-8010 Graz (Austria)

    2017-07-10

    How magnetic energy is injected and released in the solar corona, keeping it heated to several million degrees, remains elusive. Coronal heating generally increases with increasing magnetic field strength. From a comparison of a nonlinear force-free model of the three-dimensional active region coronal field to observed extreme-ultraviolet loops, we find that (1) umbra-to-umbra coronal loops, despite being rooted in the strongest magnetic flux, are invisible, and (2) the brightest loops have one foot in an umbra or penumbra and the other foot in another sunspot’s penumbra or in unipolar or mixed-polarity plage. The invisibility of umbra-to-umbra loops is new evidence that magnetoconvection drives solar-stellar coronal heating: evidently, the strong umbral field at both ends quenches the magnetoconvection and hence the heating. Broadly, our results indicate that depending on the field strength in both feet, the photospheric feet of a coronal loop on any convective star can either engender or quench coronal heating in the loop’s body.

  10. Ex vivo and in vitro determination of the axial rotational axis of the human thoracic spine.

    Science.gov (United States)

    Molnár, Szabolcs; Manó, Sándor; Kiss, László; Csernátony, Zoltán

    2006-12-15

    Different geometrical and biomechanical evaluations were performed to determine the axial rotational axis of the thoracic spine. Our research group has been dealing with the determination of the axial rotational axis of the thoracic spine. Here, we would like to present the geometrical and experimental results of our trials. With our experiments, we are trying to evaluate the contradictions of the related literature. In the present state, we know quite a lot about the biomechanics of healthy and pathologic spines. Nevertheless, for a seemingly simple question like the position of the axial rotation of the thoracic spine, the literature gives contradicting results. During correction of a scoliotic deformity, when trying to correct the pathologic rotation, not knowing the physiologic rotation can be hazardous. We wanted to clarify this question, so we examined the thoracic spine in many different ways. First, we examined the problem from a geometrical point of view then we modeled the different rotational axes by studying the change in volume of the spinal canal. Finally, we used cadaver spines that we rotated and examined with radiographs and digital pictures. Based on the results, we made the following establishments: most of the center points fell on the anterior half of the vertebral body or into the spinal canal, basically on the midsagittal axis of the vertebra. The rib cage has a significant effect on the place of the axis. After removing the ribs, the axis of axial rotation moved forward. After evaluating the results, we determined that the most likely place for the rotational axis is on the median-sagittal plane, in the anterior portion of the spinal canal.

  11. Establishing Cephalometric Norms using Sagittal and Vertical Occlusal Cephalometric Analysis of Pancherz for Dakshina Kannada Children.

    Science.gov (United States)

    Sahitya, M; Shashidhar, E P; Chidanandeswara, G C; Shetty, Sharath Kumar B; Kumar, Y Mahesh

    2015-07-01

    The purpose of this study was to establish norms for the sagittal occlusal (SO) and vertical occlusal (VO) cephalometric analyses of Pancherz for Dakshina Kannada children and to analyze and compare the difference between boys and girls of same age group (10-14 years). Two hundred and sixty-three (132 boys and 131 girls) children of Dakshina Kannada were included in this study. Lateral cephalometric radiographs of children belonging to the age group of 10-14 years were taken. Dental lateral cephalometric radiographs were obtained and these cephalometric radiographs were then manually traced. All the parameters considered in the Pancherz analysis were considered while establishing the norms for Dakshina Kannada children. Statistically significant sex differences were found for 9 of 11 parameters in the sagittal occlusal analysis, and 10 of 10 in the Vertical occlusal analysis. For the sagittal and Vertical occlusal analyses of Pancherz a separate sex-specific standards are needed for Dakshina Kannada children.

  12. Splintage in the treatment of sagittal band incompetence and extensor tendon subluxation.

    Science.gov (United States)

    Peelman, J; Markiewitz, A; Kiefhaber, T; Stern, P

    2015-03-01

    This study assessed the success of splintage for traumatic and atraumatic sagittal band incompetence and its relationship to the duration of symptoms before treatment. A retrospective review of all patients with sagittal band incompetence treated with splintage was performed. All patients had extensor tendon subluxation on physical examination. Ninety-two patients were included: 68 traumatic and 24 atraumatic. Subluxation resolved with splintage in 77 patients. Traumatic tendon subluxation resolved in 95% of acute injuries, 100% of subacute injuries, and 67% of chronic injures. Atraumatic tendon subluxation resolved in 100% of patients with acute presentation, 67% of patients with subacute presentation, and 57% of patients with chronic presentation. Surgery was rarely required. Splintage proved very effective for acute sagittal band incompetence, regardless of causation, but decreased in efficiency with chronicity. Level 4. © The Author(s) 2014.

  13. Bone formation in axial spondyloarthritis.

    Science.gov (United States)

    Lories, Rik J; Haroon, Nigil

    2014-10-01

    The success of targeted therapies directed against tumor necrosis factor for patients with spondyloarthritis has shifted the focus of physicians and scientists towards the prevention of structural damage to the involved structures, in particular the sacroiliac joints and the spine, to avoid loss of function and disability. Structural damage to the skeleton as witnessed by radiography mainly consists of new bone formation potentially progressively leading to spine or joint ankylosis. This important long-term outcome parameter has been difficult to study, not alone because the time window for change may be long but also because human tissues with direct translational relevance are rarely available. Data from rodent models have identified growth factor signaling pathways as relevant targets. Both human and animal studies have tried to understand the link between inflammation and new bone formation. At the current moment, most evidence points towards a strong link between both but with the question still lingering about the sequence of events, disease triggers, and the interdependence of both features of disease. New discoveries such as a masterswitch T cell population that carries the IL23 receptor and the analysis of auto-antibodies directed again noggin and sclerostin are contributing to innovative insights into the pathophysiology of disease. Long-term data with tumor necrosis factor (TNF) inhibitors also suggest that some window of opportunity may exist to inhibit structural disease progression. All these data provide support for a further critical analysis of the available datasets and boost research in the field. The introduction of novel disease definitions, in particular the characterization of non-radiographic axial spondyloarthritis patients, will likely be instrumental in our further understanding of structural damage. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Sagittal alignment and complications following lumbar 3-column osteotomy: does the level of resection matter?

    Science.gov (United States)

    Ferrero, Emmanuelle; Liabaud, Barthelemy; Henry, Jensen K; Ames, Christopher P; Kebaish, Khaled; Mundis, Gregory M; Hostin, Richard; Gupta, Munish C; Boachie-Adjei, Oheneba; Smith, Justin S; Hart, Robert A; Obeid, Ibrahim; Diebo, Bassel G; Schwab, Frank J; Lafage, Virginie

    2017-11-01

    OBJECTIVE Three-column osteotomy (3CO) is a demanding technique that is performed to correct sagittal spinal malalignment. However, the impact of the 3CO level on pelvic or truncal sagittal correction remains unclear. In this study, the authors assessed the impact of 3CO level and postoperative apex of lumbar lordosis on sagittal alignment correction, complications, and revisions. METHODS In this retrospective study of a multicenter spinal deformity database, radiographic data were analyzed at baseline and at 1- and 2-year follow-up to quantify spinopelvic alignment, apex of lordosis, and resection angle. The impact of 3CO level and apex level of lumbar lordosis on the sagittal correction was assessed. Logistic regression analyses were performed, controlling for cofounders, to investigate the effects of 3CO level and apex level on intraoperative and postoperative complications as well as on the need for subsequent revision surgery. RESULTS A total of 468 patients were included (mean age 60.8 years, mean body mass index 28.1 kg/m 2 ); 70% of patients were female. The average 3CO resection angle was 25.1° and did not significantly differ with regard to 3CO level. There were no significant correlations between the 3CO level and amount of sagittal vertical axis or pelvic tilt correction. The postoperative apex level significantly correlated with greater correction of pelvic tilt (2° per more caudal level, R = -0.2, p = 0.006). Lower-level 3CO significantly correlated with revisions for pseudarthrosis (OR = 3.88, p = 0.001) and postoperative motor deficits (OR = 2.02, p = 0.026). CONCLUSIONS In this study, a more caudal lumbar 3CO level did not lead to greater sagittal vertical axis correction. The postoperative apex of lumbar lordosis significantly impacted pelvic tilt. 3CO levels that were more caudal were associated with more postoperative motor deficits and revisions.

  15. Is there a sagittal imbalance of the spine in isthmic spondylolisthesis? A correlation study

    Science.gov (United States)

    Ilharreborde, Brice; Dauzac, Cyril; Lenoir, Thibault; Rillardon, Ludovic; Guigui, Pierre

    2007-01-01

    Recent studies suggested a predominant role of spinopelvic parameters to explain lumbosacral spondylolisthesis pathogeny. We compare the pelvic incidence and other parameters of sagittal spinopelvic balance in adolescents and young adults with developmental spondylolisthesis to those parameters in a control group of healthy volunteers. We compared the angular parameters of the sagittal balance of the spine in a cohort of 244 patients with a developmental L5–S1 spondylolisthesis with those of a control cohort of 300 healthy volunteers. A descriptive and correlation study was performed. The L5 anterior slipping and lumbosacral kyphosis in spondylolisthesis patients was described using multiple regression analysis study. Our study demonstrates that the related measures of sagittal spinopelvic alignment are disturbed in adolescents and young adults with developmental spondylolisthesis. These subjects stand with an increased sacral slope, pelvic tilt and lumbar lordosis but with a decreased thoracic kyphosis. Pelvic incidence was significantly higher in spondylolisthesis patients as compared with controls but was not clearly correlated with the grade of slipping. We showed the same “sagittal balance strategy” in spondylolisthesis patients as in the control group regarding correlations between pelvic incidence, sacral slope, pelvic tilt and lumbar lordosis. We believe that the lumbosacral kyphosis is a stronger factor than pelvic incidence which need to be taken into account as a predominant factor in theories of pathogenesis of lumbosacral spondylolithesis. We thus believe that increased lumbar lordosis associated with L5–S1 spondylolisthesis is secondary to the high pelvic incidence and is an important factor causing high shear stresses at the L5–S1 pars interarticularis. However, the “local” sagittal imbalance of the lumbosacral junction is compensated by adjacent mobile segments in the upper lumbar spine, the pelvis orientation and the thoracic spine

  16. [SPINO-PELVIC SAGITTAL ALIGNMENT IN PATIENTS WITH HIGH-GRADE L5 ISTHMIC SPONDYLOLISTHESIS].

    Science.gov (United States)

    Yang, Xi; Kong, Qingquan; Song, Yueming; Liu, Limin; Li, Tao; Gong, Quan; Zeng, Jiancheng; Liu, Hao

    2016-01-01

    To observe the character of spino-pelvic sagittal alignment in patients with high-grade L5 isthmic spondylolisthesis, and to analyze the sagittal alignment alteration after operation. Between January 2009 and June 2014, 25 patients with high-grade L5 isthmic spondylolisthesis underwent posterior surgery, and the clinical data were retrospectively analyzed as study group. There were 14 males and 11 females with a mean age of 42.5 years (range, 20-65 years). The mean disease duration was 6 months (range, 3-12 months). According to the Meyerding evaluating system, 15 cases were rated as degree III, and 10 cases as degree IV. Eighty healthy adult volunteers were recruited simultaneously as control group. The lumbar sacral angle (LSA), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), lumbar lordosis (LL), thoracic kyphosis (TK), and sagittal vertical axis (SVA) were measured on preoperative and last follow-up standing full length lateral X-ray films. And these parameters were compared between study group (preoperative parameters) and control group. Then the patients in study group were divided into 2 subgroups according to Hresko's method: the balanced pelvis subgroup (n = 14) and unbalanced pelvis subgroup (n = 11). The sagittal parameters were compared between 2 subgroups, and the alteration of sagittal parameters before surgery and at last follow-up was analyzed in each subgroup respectively. All patients in study group were followed up 18 months on average (range, 6-48 months). After surgery, spondylolisthesis was reduced from degree III to degree 0 in 12 cases and to degree I in 3 cases, and from degree IV to degree 0 in 6 cases and to degree I in 4 cases. Bone fusion was obtained in all patients at last follow-up. The preoperative PI, SS, PT, and SVA of study group were significantly greater than those of control group (P spondylolisthesis have greater PI, abnormal lumbosacral kyphosis, and sagittal imbalance.

  17. Identification and treatment of osteochondritis dissecans of the distal sagittal ridge of the third metacarpal bone.

    Science.gov (United States)

    Wright, I M; Minshall, G J

    2014-09-01

    Osteochondritis dissecans (OCD) of the distal sagittal ridge of the third metacarpal bone (McIII) has not previously been described in the literature. To describe the clinical, radiological and arthroscopic features of OCD of the distal sagittal ridge of the McIII and to report outcome in a series of cases. Retrospective case series. Case records and images of horses with OCD of the distal sagittal ridge of the McIII admitted to a single referral centre between February 2006 and February 2013 were reviewed. Follow-up information was obtained by telephone questionnaire and/or racing performance. Osteochondritis dissecans of the distal sagittal ridge of the McIII was found in 16 lame horses; 9 unilaterally and 7 bilaterally. Lesions were consistently identified with flexed lateromedial radiographs and in 21 joints in dorsopalmar projections also. These were arthroscopically accessible from the dorsal compartment with metacarpophalangeal joints maximally flexed. This permitted fragment removal and lesion debridement. Thirteen of 14 horses with follow-up of ≥12 months post surgery performed athletically including 11 of 12 Thoroughbreds that raced. Unlike more proximal lesions, OCD of the distal sagittal ridge appears to affect the McIII preferentially. Lesions were identified on dorsopalmar and flexed lateromedial radiographs only and are amenable to arthroscopic surgery. Clinicians should be aware of the potential for OCD to affect the distal sagittal ridge of the McIII together with the radiographic projections needed to identify its presence. A modified arthroscopic approach to the dorsal metacarpophalangeal joint is necessary in order to access lesions. © 2013 EVJ Ltd.

  18. Lumbar sagittal contour after posterior interbody fusion: threaded devices alone versus vertical cages plus posterior instrumentation.

    Science.gov (United States)

    Klemme, W R; Owens, B D; Dhawan, A; Zeidman, S; Polly, D W

    2001-03-01

    An observational radiographic study examining lumbar sagittal contour of patients undergoing posterior interbody arthrodesis. To compare operative alterations of lumbar sagittal contour after posterior interbody fusion using threaded interbody devices alone versus vertical cages combined with posterior compression instrumentation. Technique-related alterations of lumbar sagittal contour during interbody arthrodesis have received little attention in the spinal literature. Standing lumbar radiographs were measured for preoperative and postoperative segmental lordosis at levels undergoing posterior interbody arthrodesis using either stand-alone side-by-side threaded devices or vertical cages combined with posterior transpedicular compression instrumentation. Sagittal plane segmental correction (or loss of correction) was calculated and statistically compared. The radiographs of 30 patients (34 spinal segments) undergoing lumbar or lumbosacral arthrodesis were compared. Seventeen patients (18 segments) had undergone interbody fusion using threaded cages,whereas 13 patients (16 segments) underwent fusion using vertically oriented mesh cages combined with posterior compression instrumentation. Preoperative segmental lordosis averaged 8 degrees for both groups. For patients undergoing fusion with threaded cages, there was a mean lordotic loss of 3 degrees/segment. For patients undergoing fusion with vertically oriented mesh cages combined with posterior compression instrumentation,there was a mean lordotic gain of 5 degrees/segment. This difference in segmental sagittal plane contour was highly significant (P = 0.00). Threaded fusion devices placed under interbody distraction with the endplates parallel fail to preserve or reestablish segmental lordosis. Vertical cages, however, when combined with posterior compression instrumentation, not only maintain segmental lordosis, but also can correct sagittal plane deformity.

  19. Ultrahigh-Resolution Combined Coronal Optical Coherence Tomography Confocal Scanning Ophthalmoscope (OCT/SLO): a pilot study

    International Nuclear Information System (INIS)

    Rosen, R.B.; Garcia, P.M.T.; Muldoon, T.O.; Velthoven van, M.E.J.; Cucu, R.G.; Podoleanu, A.G.; De Smet, M.D.

    2007-01-01

    To evaluate clinical images from a prototype ultrahigh resolution (UHR) combined coronal optical coherence tomography/confocal scanning ophthalmoscope (OCT/SLO) and to compare them to standard-resolution OCT/SLO images on the same patients. Cross-sectional pilot-study. Sixty-six eyes of 42 patients with various macular pathologies, such as age-related macular degeneration, macular edema, macular hole, central serous retinopathy, epiretinal membrane and posterior vitreous traction syndrome. Each subject was first scanned with a standard-resolution OCT/SLO that has an axial resolution of ∼ 10 micron. Immediately following, patients were scanned with the prototype UHR OCT/SLO device. The UHR system employs a compact super luminescent diode (SLD) with a 150 nm bandwidth centered at 890 nm, which allows imaging of the retina with an axial resolution of 3 microns. Both coronal and longitudinal OCT scans were acquired with each system, and compared side-by-side. Scan quality was assessed for the observer's ability to visualize the vitreo-retinal interface and retinal layers - in particular of the outer retina/RPE/choroidal interface, increased discrimination of pathological changes, and better signal intensity. Ultrahigh and standard-resolution coronal and longitudinal OCT/SLO images of macular pathologies. In the side-by-side comparison with the commercial standard-resolution OCT/SLO images, the scans in the Ultrahigh resolution OCT/SLO images were superior in 85 % of cases. Relatively poor quality images were attributed to lower signal-to-noise ratio, limited focusing, or media opacities. Several images that had a better signal intensity in the standard-resolution OCT/SLO system were found to show more retinal detail in the UHR system. In general, intraretinal layers in the UHR OCT/SLO images were better delineated in both coronal and longitudinal scans. Enhanced details were also seen in the outer retina/RPE/choroidal complex. The UHR OCT/SLO system produced better

  20. Diagnostic value of axial CT scan

    Energy Technology Data Exchange (ETDEWEB)

    Kiuchi, Sousuke (Tsukuba Univ., Sakura, Ibaraki (Japan))

    1983-03-01

    Axial CT scan was used to investigate the radiological details of the temporal bone of 33 patients with chronic otitis media, secondary cholesteatoma, sensorineural hearing loss, Meniere disease, vertigo, facial spasm, and neoplasma. The axial scans showed anatomic details of the temporal bone, and at the same time clearly demonstrated the extent of the soft-tissue masses in the middle ears, as well as the destructions of the ossicles. Bone changes of the anterior walls of the epitympanum and external auditory meatus were more clearly demonstrated than by coronary CT scan. However, the axial scan had the disadvantages in demonstrating the stapes, crista transversa, and the mastoid portion of the facial canal.

  1. Axial force measurement for esophageal function testing

    DEFF Research Database (Denmark)

    Gravesen, Flemming Holbæk; Funch-Jensen, Peter; Gregersen, Hans

    2009-01-01

    force (force in radial direction) whereas the bolus moves along the length of esophagus in a distal direction. Force measurements in the longitudinal (axial) direction provide a more direct measure of esophageal transport function. The technique used to record axial force has developed from external...... documented using imaging modalities such as radiography and scintigraphy. This inconsistency using manometry has also been documented by axial force recordings. This underlines the lack of information when diagnostics are based on manometry alone. Increasing the volume of a bag mounted on a probe...

  2. Mitochondrial genomes and comparative analyses of Culex camposi, Culex coronator, Culex usquatus and Culex usquatissimus (Diptera:Culicidae), members of the coronator group

    OpenAIRE

    Demari-Silva, B; Foster, PG; de Oliveira, TMP; Bergo, ES; Sanabani, SS; Pessôa, R; Sallum, MAM

    2015-01-01

    Abstract Background The Coronator Group currently encompasses six morphologically similar species (Culex camposi Dyar, Culex coronator Dyar and Knab, Culex covagarciai Forattini, Culex usquatus Dyar, Culex usquatissimus Dyar, and Culex ousqua Dyar). Culex coronator has been incriminated as a potential vector of West Nile Virus (WNV), Saint Louis Encephalitis Virus (SLEV), and Venezuelan Equine Encephalitis Virus (VEEV). The complete mito...

  3. Surgical Access to a Complex Composite Odontoma via Sagittal Split Osteotomy of the Mandible

    Science.gov (United States)

    Periasamy, Senthilnathan; Devadoss, Poorna; Kumar, Santhosh P

    2017-01-01

    This case report presents the removal of complex composite odontoma in a young patient in the right body of mandible via the unilateral sagittal splitting of the mandible. This article shows that sagittal split osteotomy of the mandible can be very useful to access various pathologies in the body, angle, and ramus of the mandible and to navigate lesions that are in proximity to the inferior alveolar nerve. This technique also helps in avoiding postoperative morbidity when compared to other conventional surgical approaches. It can be used to remove large cysts, benign non-infiltrative tumours of the mandible, odontogenic myxoma, large odontoma, and deeply impacted lower third molars. PMID:29441249

  4. [The theoretical substantiation of myofunctional correction of sagittal occlusion abnormalities and temporomandibular joint dysfunction].

    Science.gov (United States)

    Danilova, M A; Ishmurzin, P V; Zakharov, S V

    2012-01-01

    Simulation in 3D-model of skeletal forms of sagittal malocclusion revealed tendency in tonus' modification of muscles of mastication in formation of distal and mesial occlusion. It's shown that distal occlusion is characterized by hypotonic condition of muscles of mastication, except posterior fibers of temporal muscle. Mesial occlusion is characterized by complex combination of muscle tone with prevalence of hypotonic condition of anterior fibers of temporal muscle, superficial portion of masseter muscle and medial pterygoid muscle. We have detected that using of myofunctional devices in treatment of sagittal malocclusion, temporomandibular joint dysfunction promotes of tone increasing of muscles of mastication.

  5. Coronal tibiofemoral subluxation in knee osteoarthritis.

    Science.gov (United States)

    Khamaisy, Saker; Zuiderbaan, Hendrik A; Thein, Ran; Gladnick, Brian P; Pearle, Andrew D

    2016-01-01

    To analyze knees in varying stages of osteoarthritis (OA) for the presence of coronal tibiofemoral (CTF) subluxation and to determine if CTF subluxation severity is related to knee OA worsening. We retrospectively evaluated CTF subluxation and limb alignment in 113 patients with different stages of knee OA who were being considered for an arthroplasty procedure. Knee OA was classified as "mild" or "severe" according to Kellgren-Lawrence scale. CTF subluxation was measured in the study groups and in 40 knees of healthy controls using software developed specifically on the basis of Iterative Closest Point mathematical algorithm. Mean CTF subluxation in "mild OA" and "severe OA" groups was 3.5% (±2) and 3.5 % (±5) of the tibial plateau, respectively. For both the mild and severe OA groups, CTF subluxation was significantly increased compared to the 1.4% (±1) CTF subluxation in the control group, (p < 0.0001) and (p = 0.012), respectively. However, there was no significant difference in CTF subluxation between the mild OA and severe OA groups (p = 0.75). Limb varus malalignment in mild OA and severe OA groups was 3.6° (±2.2) and 5.3° (±2.6), respectively. Both significantly increased comparing to the 1° (±0.7) control group alignment (p < 0.0001). Varus malalignment in the severe OA group was significantly increased comparing to the mild OA group (p = 0.0003). CTF subluxation is a radiographic finding related to knee OA which occurs mainly in the early stages of the osteoarthritic process and stagnates as OA progresses.

  6. The Longitudinal Evolution of Equatorial Coronal Holes

    Science.gov (United States)

    Krista, Larisza D.; McIntosh, Scott W.; Leamon, Robert J.

    2018-04-01

    In 2011, three satellites—the Solar-Terrestrial RElations Observatory A & B, and the Solar Dynamics Observatory (SDO)—were in a unique spatial alignment that allowed a 360° view of the Sun. This alignment lasted until 2014, the peak of solar cycle 24. Using extreme ultraviolet images and Hovmöller diagrams, we studied the lifetimes and propagation characteristics of coronal holes (CHs) in longitude over several solar rotations. Our initial results show at least three distinct populations of “low-latitude” or “equatorial” CHs (below 65^\\circ latitude). One population rotates in retrograde direction and coincides with a group of long-lived (over sixty days) CHs in each hemisphere. These are typically located between 30° and 55^\\circ , and display velocities of ∼55 m s‑1 slower than the local differential rotation rate. A second, smaller population of CHs rotate prograde, with velocities between ∼20 and 45 m s‑1. This population is also long-lived, but observed ±10° from the solar equator. A third population of CHs are short-lived (less than two solar rotations), and they appear over a wide range of latitudes (±65°) and exhibit velocities between ‑140 and 80 m s‑1. The CH “butterfly diagram” we developed shows a systematic evolution of the longer-lived holes; however, the sample is too short in time to draw conclusions about possible connections to dynamo-related phenomena. An extension of the present work to the 22 years of the combined SOHO–SDO archives is necessary to understand the contribution of CHs to the decadal-scale evolution of the Sun.

  7. Capacitive axial position and speed transduction system

    International Nuclear Information System (INIS)

    Jimenez D, H.; Flores Ll, H.; Cabral P, A.; Ramirez J, F.J.; Galindo, S.

    1984-01-01

    A new and inexpensive circuit arrangement of a capacitive axial position and speed transduction system is described. Design details and the theory of operation of the device are briefly outlined together with performance results. (author)

  8. Two pad axially grooved hydrostatic bearing

    Science.gov (United States)

    San Andres, Luis A. (Inventor)

    1995-01-01

    A hydrostatic bearing having two axial grooves on opposite sides of the bearing for breaking the rotational symmetry in the dynamic force coefficients thus reducing the whirl frequency ratio and increasing the damping and stiffness of the hydrostatic bearing.

  9. Differences in early sagittal plane alignment between thoracic and lumbar adolescent idiopathic scoliosis.

    Science.gov (United States)

    Schlösser, Tom P C; Shah, Suken A; Reichard, Samantha J; Rogers, Kenneth; Vincken, Koen L; Castelein, René M

    2014-02-01

    It has previously been shown that rotational stability of spinal segments is reduced by posteriorly directed shear loads that are the result of gravity and muscle tone. Posterior shear loads act on those segments of the spine that are posteriorly inclined, as determined by each individual's inherited sagittal spinal profile. Accordingly, it can be inferred that certain sagittal spinal profiles are more prone to develop a rotational deformity that may lead to idiopathic scoliosis; and lumbar scoliosis, on one end of the spectrum, develops from a different sagittal spinal profile than thoracic scoliosis on the other end. To examine the role of sagittal spinopelvic alignment in the etiopathogenesis of different types of idiopathic scoliosis. Multicenter retrospective analysis of lateral radiographs of patients with small thoracic and lumbar adolescent idiopathic scoliotic curves. We included 192 adolescent idiopathic scoliosis patients with either a thoracic (n=128) or lumbar (n=64) structural curve with a Cobb angle of less than 20° were studied. Children with other spinal pathology or with more severe idiopathic scoliosis were excluded, because this disturbs their original sagittal profile. Subjects who underwent scoliosis screening and had a normal spine were included in the control cohort (n=95). Thoracic kyphosis, lumbar lordosis, T9 sagittal offset, C7 and T4 sagittal plumb lines, pelvic incidence, pelvic tilt, and sacral slope, as well as parameters describing orientation in space of each individual vertebra between C7 and L5 and length of the posteriorly inclined segment. On standardized lateral radiographs of the spine, a systematic, semi-automatic measurement of the different sagittal spinopelvic parameters was performed for each subject using in-house developed computer software. Early thoracic scoliosis showed a significantly different sagittal plane from lumbar scoliosis. Furthermore, both scoliotic curve patterns were different from controls, but in a

  10. High temperature co-axial winding transformers

    Science.gov (United States)

    Divan, Deepakraj M.; Novotny, Donald W.

    1993-01-01

    The analysis and design of co-axial winding transformers is presented. The design equations are derived and the different design approaches are discussed. One of the most important features of co-axial winding transformers is the fact that the leakage inductance is well controlled and can be made low. This is not the case in conventional winding transformers. In addition, the power density of co-axial winding transformers is higher than conventional ones. Hence, using co-axial winding transformers in a certain converter topology improves the power density of the converter. The design methodology used in meeting the proposed specifications of the co-axial winding transformer specifications are presented and discussed. The final transformer design was constructed in the lab. Co-axial winding transformers proved to be a good choice for high power density and high frequency applications. They have a more predictable performance compared with conventional transformers. In addition, the leakage inductance of the transformer can be controlled easily to suit a specific application. For space applications, one major concern is the extraction of heat from power apparatus to prevent excessive heating and hence damaging of these units. Because of the vacuum environment, the only way to extract heat is by using a cold plate. One advantage of co-axial winding transformers is that the surface area available to extract heat from is very large compared to conventional transformers. This stems from the unique structure of the co-axial transformer where the whole core surface area is exposed and can be utilized for cooling effectively. This is a crucial issue here since most of the losses are core losses.

  11. Axial model in curved space-time

    Energy Technology Data Exchange (ETDEWEB)

    Barcelos-Neto, J.; Farina, C.; Vaidya, A.N.

    1986-12-11

    We study the axial model in a background gravitational field. Using the zeta-function regularization, we obtain explicitly the anomalous divergence of the axial-vector current and the exact generating functional of the theory. We show that, as a consequence of a space-time-dependent metric, all differential equations involved in the theory generalize to their covariantized forms. We also comment on the finite-mass renormalization exhibited by the pseudoscalar field and the form of the fermion propagator.

  12. Dechanneling function for relativistic axially channeled electrons

    International Nuclear Information System (INIS)

    Muralev, V.A.; Telegin, V.I.

    1981-01-01

    Behaviour of the x(t) dechanneling function depending on the depth is theoretically studied. Theoretical consideration of x(t) for axial channeled relativistic electrons in anisotropic medium results in two-dimensional kinetic equation with mixed derivatives of the parabolic type. The kinetic equation in the approximation of the continuous Lindchard model for relativistic axial channeled electrons is numerically solved. The depth dependence of the x(t) dechanneling function is obtained [ru

  13. Axial forces in centrifugal compressor couplings

    Science.gov (United States)

    Ivanov, A. N.; Ivanov, N. M.; Yun, V. K.

    2017-08-01

    The article presents the results of the theoretical and experimental investigation of axial forces arising in the toothed and plate couplings of centrifugal compressor shaft lines. Additional loads on the thrust bearing are considered that can develop in the toothed couplings as a result of coupled rotors misalignment. Design relationships to evaluate the level of axial forces and recommendations for their reduction in the operating conditions are given.

  14. High harmonic generation from axial chiral molecules.

    Science.gov (United States)

    Wang, Dian; Zhu, Xiaosong; Liu, Xi; Li, Liang; Zhang, Xiaofan; Lan, Pengfei; Lu, Peixiang

    2017-09-18

    Axial chiral molecules, whose stereogenic element is an axis rather than a chiral center, have attracted widespread interest due to their important application, such as asymmetric synthesis and chirality transfer. We investigate high harmonic generation from axial chiral molecules with bichromatic counterrotating circularly polarized laser fields. High harmonic generation from three typical molecules: (Sa)-3-chloropropa-1,2-dien-1-ol, propadiene, and (Ra)-2,3-pentadiene is simulated with time-dependent density-functional theory and strong field approximation. We found that harmonic spectra for 3D oriented axial chiral molecules exhibit obvious circular dichroism. However, the circular dichroism of High harmonic generation from an achiral molecule is much trivial. Moreover, the dichroism of high harmonic generation still exists when axial chiral molecules are 1D oriented,such as (Sa) -3-chloropropa-1,2-dien-1-ol. For a special form of axial chiral molecules with the formula abC=C=Cab (a, b are different substituents), like (Ra)-2,3-pentadiene, the dichroism discriminations disappear when the molecules are only in 1D orientation. The circular dichroism of high harmonic generation from axial chiral molecules is well explained by the trajectory analysis based on the semiclassical three-step mechanism.

  15. The driver in flares and coronal mass ejections: Magnetic expansion

    Science.gov (United States)

    Moore, Ronald L.

    1988-01-01

    Chromospheric filaments, and hence the sheared magnetic fields that they trace, are observed to erupt in flares and coronal mass ejections. In the eruption, the filament-traced field is seen to expand in volume. For frozen-in magnetic field and isotropic expansion, the magnetic energy in a flux tube decreases as the flux tube expands. The amount of expansion of the magnetic field and the corresponding decrease in magnetic energy in a filament-eruption flare and/or coronal mass ejection can be estimated to order of magnitude from the observed expansion of the erupting filament. This evaluation for filament-eruption events in which the filament expansion is clearly displayed gives decreases in magnetic energy of the order of the total energy of the accompanying flare and/or coronal mass ejection. This simple expanding flux tube model can also fit the observed acceleration of coronal mass ejections, if it is assumed that the increase in mechanical energy of the mass ejection comes from the magnetic energy decrease in the expansion. These results encourage the view that magnetic expansion such as seen in filament eruptions drives both the plasma particle energization in flares and the bulk mass motion in coronal mass ejections.

  16. Comparative Study of Skeletal Stability between Postoperative Skeletal Intermaxillary Fixation and No Skeletal Fixation after Bilateral Sagittal Split Ramus Osteotomy

    DEFF Research Database (Denmark)

    Hartlev, Jens; Godtfredsen, Erik; Andersen, Niels Trolle

    2014-01-01

    OBJECTIVES: The purpose of the present study was to evaluate skeletal stability after mandibular advancement with bilateral sagittal split osteotomy. MATERIAL AND METHODS: Twenty-six patients underwent single-jaw bilateral sagittal split osteotomy (BSSO) to correct skeletal Class II malocclusion....

  17. A genome-wide association study identifies susceptibility loci for nonsyndromic sagittal craniosynostosis near BMP2 and within BBS9

    NARCIS (Netherlands)

    Justice, C.M.; Yagnik, G.; Kim, Y.; Peter, I.; Jabs, E.W.; Erazo, M.; Ye, X.; Ainehsazan, E.; Shi, L.; Cunningham, M.L.; Kimonis, V.; Roscioli, T.; Wall, S.A.; Wilkie, A.O.; Stoler, J.; Richtsmeier, J.T.; Heuze, Y.; Sanchez-Lara, P.A.; Buckley, M.F.; Druschel, C.M.; Mills, J.L.; Caggana, M.; Romitti, P.A.; Kay, D.M.; Senders, C.; Taub, P.J.; Klein, O.D.; Boggan, J.; Zwienenberg-Lee, M.; Naydenov, C.; Kim, J.; Wilson, A.F.; Boyadjiev, S.A.

    2012-01-01

    Sagittal craniosynostosis is the most common form of craniosynostosis, affecting approximately one in 5,000 newborns. We conducted, to our knowledge, the first genome-wide association study for nonsyndromic sagittal craniosynostosis (sNSC) using 130 non-Hispanic case-parent trios of European

  18. Cost, operation and hospitalization times in distraction osteogenesis versus sagittal split osteotomy

    NARCIS (Netherlands)

    van Strijen, P. J.; Breuning, K. H.; Becking, A. G.; Perdijk, F. B. T.; Tuinzing, D. B.

    2003-01-01

    Distraction osteogenesis in 'common' surgical orthodontics is mentioned as an alternative for conventional sagittal split osteotomy. After a 'learning curve' in the surgical skills of distraction, the two techniques can be compared concerning time and cost aspects. Forty-seven patients (male n=28,

  19. An Assessment of Correlation between Dermatoglyphic Patterns and Sagittal Skeletal Discrepancies.

    Science.gov (United States)

    George, Susha Miriam; Philip, Biju; Madathody, Deepika; Mathew, Manu; Paul, Jose; Dlima, Johnson Prakash

    2017-03-01

    Investigators over years have been fascinated by dermatoglyphic patterns which has led to the development of dermatoglyphics as a science with numerous applications in various fields other than being the best and most widely used method for personal identification. To assess the correlation between dermatoglyphic patterns and sagittal skeletal discrepancies. A total of 180 patients, aged 18-40 years, were selected from those who attended the outpatient clinic of the Deparment of Orthodontics and Dentofacial Orthopedics, Mar Baselios Dental College, Kothamangalam, Kerala, India. The fingerprints of both hands were taken by ink and stamp method after proper hand washing. The patterns of arches, loops and whorls in fingerprints were assessed. The total ridge count was also evaluated. Data was also sent to the fingerprint experts for expert evaluation. The sagittal jaw relation was determined from the patient's lateral cephalogram. The collected data was then statistically analyzed using Chi-square tests, ANOVA and Post-hoc tests and a Multinomial regression prediction was also done. A significant association was observed between the dermatoglyphic pattern exhibited by eight fingers and the sagittal skeletal discrepancies (pdermatoglyphic patterns and sagittal skeletal discrepancies. Dermatoglyphics could serve as a cost effective screening tool of these craniofacial problems.

  20. [Progressive Intracranial Hypertension due to Superior Sagittal Sinus Thrombosis Following Mild Head Trauma: A Case Report].

    Science.gov (United States)

    Suto, Yuta; Maruya, Jun; Watanabe, Jun; Nishimaki, Keiichi

    2015-07-01

    Cerebral venous sinus thrombosis after mild head trauma without skull fracture or intracranial hematoma is exceptionally rare. We describe an unusual case of progressive intracranial hypertension due to superior sagittal sinus thrombosis following mild head trauma. A 17-year-old boy presented with nape pain a day after a head blow during a gymnastics competition (backward double somersault). On admission, he showed no neurological deficit. CT scans revealed no skull fractures, and there were no abnormalities in the brain parenchyma. However, his headache worsened day-by-day and he had begun to vomit. Lumbar puncture was performed on Day 6, and the opening pressure was 40 cm of water. After tapping 20 mL, he felt better and the headache diminished for a few hours. MR venography performed on Day 8 revealed severe flow disturbance in the posterior third of the superior sagittal sinus with multiple venous collaterals. Because of the beneficial effects of lumbar puncture, we decided to manage his symptoms of intracranial hypertension conservatively with repeated lumbar puncture and administration of glycerol. After 7 days of conservative treatment, his symptoms resolved completely, and he was discharged from the hospital. Follow-up MR venography performed on Day 55 showed complete recanalization of the superior sagittal sinus. The exact mechanism of sinus thrombosis in this case is not clear, but we speculate that endothelial damage caused by shearing stress because of strong rotational acceleration or direct impact to the superior sagittal sinus wall may have initiated thrombus formation.

  1. Direct sagittal CT scanning in the diagnosis of pituitary fossa tumours and posterior fossa pathology

    International Nuclear Information System (INIS)

    Podlas, H.

    1981-01-01

    Two independent methods are presented for multidirectional CT scanning of the brain using the Philips Tomoscan 300. The advantages in scanning pituitary fossa tumours and pathology of the posterior fossa are discussed. No additional software or modifications are required. Direct sagittal scanning is particularly advantageous for accurate assessment of the size of pituitary tumours and intrasellar lesions requiring surgical intervention or radiation therapy. (Auth.)

  2. The Association between Maxillomandibular Sagittal Relationship and Pharyngeal Airway Passage Dimensions

    Directory of Open Access Journals (Sweden)

    Madhurima Nanda

    2012-01-01

    Conclusion : Sagittal skeletal pattern had a close association between the pharyngeal airway passage and the dimensions of the pharyngeal airway passage. The dimensions of pharyngeal airway passage were decreased from Class III to Class I and Class I to Class II subjects.

  3. 3D analysis of condylar remodelling and skeletal relapse following bilateral sagittal split advancement osteotomies

    NARCIS (Netherlands)

    Xi, T.; Schreurs, R.; Loon, B. van; Koning, M.J. de; Berge, S.J.; Hoppenreijs, T.J.; Maal, T.J.J.

    2015-01-01

    A major concern in mandibular advancement surgery using bilateral sagittal split osteotomies (BSSO) is potential postoperative relapse. Although the role of postoperative changes in condylar morphology on skeletal relapse was reported in previous studies, no study so far has objectified the precise

  4. Skin movement errors in measurement of sagittal lumbar and hip angles in young and elderly subjects.

    Science.gov (United States)

    Kuo, Yi-Liang; Tully, Elizabeth A; Galea, Mary P

    2008-02-01

    Errors in measurement of sagittal lumbar and hip angles due to skin movement on the pelvis and/or lateral thigh were measured in young (n = 21, age = 18.6 +/- 2.1 years) and older (n = 23, age = 70.9 +/- 6.4 years) age groups. Skin reference markers were attached over specific landmarks of healthy young and elderly subjects, who were videotaped in three static positions of hip flexion using the 2D PEAK Motus video analysis system. Sagittal lumbar and hip angles were calculated from skin reference markers and manually palpated landmarks. The elderly subjects demonstrated greater errors in lumbar angle due to skin movement on the pelvis only in the maximal hip flexion position. The traditional model (ASIS-PSIS-GT-LFE) underestimated sagittal hip angle and the revised model (ASIS-PSIS-2/3Th-1/4Th) provided more accurate measurement of sagittal hip angle throughout the full available range of hip flexion. Skin movement on the pelvis had a small counterbalancing effect on the larger errors from lateral thigh markers (GT-LFE), thereby decreasing hip angle error.

  5. Optimizing Global Coronal Magnetic Field Models Using Image-Based Constraints

    Science.gov (United States)

    Jones-Mecholsky, Shaela I.; Davila, Joseph M.; Uritskiy, Vadim

    2016-01-01

    The coronal magnetic field directly or indirectly affects a majority of the phenomena studied in the heliosphere. It provides energy for coronal heating, controls the release of coronal mass ejections, and drives heliospheric and magnetospheric activity, yet the coronal magnetic field itself has proven difficult to measure. This difficulty has prompted a decades-long effort to develop accurate, timely, models of the field, an effort that continues today. We have developed a method for improving global coronal magnetic field models by incorporating the type of morphological constraints that could be derived from coronal images. Here we report promising initial tests of this approach on two theoretical problems, and discuss opportunities for application.

  6. A review of methods for evaluating the quantitative parameters of sagittal pelvic alignment.

    Science.gov (United States)

    Vrtovec, Tomaž; Janssen, Michiel M A; Likar, Boštjan; Castelein, René M; Viergever, Max A; Pernuš, Franjo

    2012-05-01

    The sagittal alignment of the pelvis represents the basic mechanism for maintaining postural equilibrium, and a number of methods were developed to assess normal and pathologic pelvic alignments from two-dimensional sagittal radiographs in terms of positional and anatomic parameters. To provide a complete overview of the existing methods for quantitative evaluation of sagittal pelvic alignment and summarize the relevant publications. Review article. An Internet search for terms related to sagittal pelvic alignment was performed to obtain relevant publications, which were further supplemented by selected publications found in their lists of references. By summarizing the obtained publications, the positional and anatomic parameters of sagittal pelvic alignment were described, and their values and relationships to other parameters and features were reported. Positional pelvic parameters relate to the position and orientation of the observed subject and are represented by the sacral slope, pelvic tilt, pelvic overhang, sacral inclination, sacrofemoral angle, sacrofemoral distance, pelvic femoral angle, pelvic angle, and sacropelvic translation. Anatomic pelvic parameters relate to the anatomy of the observed subject and are represented by the pelvisacral angle (PSA), pelvic incidence (PI), pelvic thickness (PTH), sacropelvic angle (PRS1), pelvic radius (PR), femorosacral posterior angle (FSPA), sacral table angle (STA), and sacral anatomic orientation (SAO). The review was mainly focused on the evaluation of anatomic pelvic parameters, as they can be compared among subjects and therefore among different studies. However, ambiguous results were yielded for normal and pathologic subjects, as the reported values show a relatively high variability in terms of standard deviation for every anatomic parameter, which amounts to around 10 mm for PTH and PR; 10° for PSA, PI, and SAO; 9° for PRS1 and FSPA; and 5° for STA in the case of normal subjects and is usually even

  7. Is Cervical Sagittal Imbalance a Risk Factor for Adjacent Segment Pathomechanics After Multilevel Fusion?

    Science.gov (United States)

    Patwardhan, Avinash G; Khayatzadeh, Saeed; Nguyen, Ngoc-Lam; Havey, Robert M; Voronov, Leonard I; Muriuki, Muturi G; Carandang, Gerard; Smith, Zachary A; Sears, William; Lomasney, Laurie M; Ghanayem, Alexander J

    2016-05-01

    A biomechanical study using human spine specimens. The aim of this study was to assess whether the presence of cervical sagittal imbalance is an independent risk factor for increasing the mechanical burden on discs adjacent to cervical multilevel fusions. The horizontal offset distance between the C2 plumbline and C7 vertebral body (C2-C7 Sagittal Vertical Axis (SVA)) or the angle made with vertical by a line connecting the C2 and C7 vertebral bodies (C2-C7 tilt angle) are used as radiographic measures to assess cervical sagittal balance. There is level III clinical evidence that sagittal imbalance caused by kyphotic fusions or global spinal sagittal malalignment may increase the risk of adjacent segment pathology. Thirteen human cadaveric cervical spines (Occiput-T1; age: 50.6 years; range: 21-67) were tested first in the native intact state and then after instrumentation across C4-C6 to simulate in situ two-level fusion. Specimens were tested using a previously validated experimental model that allowed measurement of spinal response to prescribed imbalance. The effects of fusion on segmental angular alignments and intradiscal pressures in the C3-C4 and C6-C7 discs, above and below the fusion, were evaluated at different magnitudes of C2-C7 tilt angle (or C2-C7 SVA). When compared with the pre-fusion state, in situ fusion across C4-C6 segments required increased flexion angulation and resulted in increased intradiscal pressure at the C6-C7 disc below the fusion in order to accommodate the same increase in C2-C7 tilt angle or C2-C7 SVA (P adjacent segment mechanical burden due to fusion became greater with increasing C2-C7 tilt angle or SVA. Cervical sagittal imbalance arising from regional and/or global spinal sagittal malalignment may play a role in exacerbating adjacent segment pathomechanics after multilevel fusion and should be considered during surgical planning. N/A.

  8. Coronal Loop Evolution Observed with AIA and Hi-C

    Science.gov (United States)

    Mulu-Moore, Fana; Winebarger, A.; Cirtain, J.; Kobayashi, K.; Korreck, K.; Golub, L.; Kuzin. S.; Walsh, R.; DeForest, C.; DePontieu, B.; hide

    2012-01-01

    Despite much progress toward understanding the dynamics of the solar corona, the physical properties of coronal loops are not yet fully understood. Recent investigations and observations from different instruments have yielded contradictory results about the true physical properties of coronal loops. In the past, the evolution of loops has been used to infer the loop substructure. With the recent launch of High Resolution Coronal Imager (Hi-C), this inference can be validated. In this poster we discuss the first results of loop analysis comparing AIA and Hi-C data. We find signatures of cooling in a pixel selected along a loop structure in the AIA multi-filter observations. However, unlike previous studies, we find that the cooling time is much longer than the draining time. This is inconsistent with previous cooling models.

  9. Solar transition region and coronal response to heating rate perturbations

    Science.gov (United States)

    Mariska, John T.

    1987-01-01

    Observations of Doppler shifts in UV emission lines formed in the solar transition region show continual plasma downflows and impulsive plasma upflows. Using numerical simulations, the authors examine the conjecture that areas of downflowing plasma are the base regions of coronal loops in which the heating is gradually decreasing and that areas of upflowing plasma are the base regions of coronal loops in which the heating rate is gradually increasing. Beginning with a coronal loop in equilibrium, the heating rate is reduced on time scales of 100, 1000, and 2000 s to 10 percent and 1 percent of the initial value, and the loop is allowed to evolve to a new equilibrium. The heating rate for the cooled models is then increased back to the initial value on the same time scales. While significant mass motions do develop in the simulations, both the emission measure and the velocity at 100,000 K do not show the characteristics present in UV observations.

  10. Influence of coronal holes on CMEs in causing SEP events

    International Nuclear Information System (INIS)

    Shen Chenglong; Yao Jia; Wang Yuming; Ye Pinzhong; Wang Shui; Zhao Xuepu

    2010-01-01

    The issue of the influence of coronal holes (CHs) on coronal mass ejections (CMEs) in causing solar energetic particle (SEP) events is revisited. It is a continuation and extension of our previous work, in which no evident effects of CHs on CMEs in generating SEPs were found by statistically investigating 56 CME events. This result is consistent with the conclusion obtained by Kahler in 2004. We extrapolate the coronal magnetic field, define CHs as the regions consisting of only open magnetic field lines and perform a similar analysis on this issue for 76 events in total by extending the study interval to the end of 2008. Three key parameters, CH proximity, CH area and CH relative position, are involved in the analysis. The new result confirms the previous conclusion that CHs did not show any evident effect on CMEs in causing SEP events. (research papers)

  11. The origin of coronal lines in Seyfert galaxies

    International Nuclear Information System (INIS)

    Korista, K.T.; Ferland, G.J.

    1989-01-01

    This paper examines the possibility that the coronal line region in Seyfert galaxies may be the result of an interstellar medium (ISM) exposed to, and subsequently photoionized by, a 'bare' Seyfert nucleus. It is shown that a 'generic' AGN continuum illuminating the warm-phase of the ISM of a spiral galaxy can produce the observed emission. In this picture the same UV-radiation cone that is responsible for the high-excitation extended narrow-line emission clouds observed out to 1-2 kpc or farther from the nuclei of some Seyfert galaxies also produces the coronal lines. Soft X-rays originating in the nucleus are Compton-scattered off the ISM, thus producing extended soft X-ray emission, as observed in NGC 4151. The results of the calculations show a basic insensitivity to the ISM density, which explains why similar coronal line spectra are found in many Seyfert galaxies of varying physical environments. 60 refs

  12. Extreme-ultraviolet observations of global coronal wave rotation

    Energy Technology Data Exchange (ETDEWEB)

    Attrill, G. D. R. [Defence Science and Technology Laboratory, Dstl Porton Down, Salisbury, Wiltshire SP4 0JQ (United Kingdom); Long, D. M.; Green, L. M.; Harra, L. K.; Van Driel-Gesztelyi, L., E-mail: gdrattrill@dstl.gov.uk [University College London, Mullard Space Science Laboratory, Holmbury St. Mary, Dorking, Surrey RH5 6NT (United Kingdom)

    2014-11-20

    We present evidence of global coronal wave rotation in EUV data from SOHO/EIT, STEREO/EUVI, and SDO/AIA. The sense of rotation is found to be consistent with the helicity of the source region (clockwise for positive helicity, anticlockwise for negative helicity), with the source regions hosting sigmoidal structures. We also study two coronal wave events observed by SDO/AIA where no clear rotation (or sigmoid) is observed. The selected events show supporting evidence that they all originate with flux rope eruptions. We make comparisons across this set of observations (both with and without clear sigmoidal structures). On examining the magnetic configuration of the source regions, we find that the nonrotation events possess a quadrupolar magnetic configuration. The coronal waves that do show a rotation originate from bipolar source regions.

  13. The Influence of Natural Head Position on the Cervical Sagittal Alignment

    Directory of Open Access Journals (Sweden)

    Kuan Wang

    2017-01-01

    Full Text Available Introduction. This study investigated the relationship between the parameters related to the natural head position and cervical segmental angles and alignment of patients with neck pain. Material and Methods. The lateral radiographs of the cervical spine were collected from 103 patients and were used to retrospectively analyze the correlation between the natural head position, cervical local sagittal angles, and alignment. Sagittal measurements were as follows: cervical curvature classification, slope of McGregor’s line (McGS, local sagittal angles (C0–C2 angle, C2–C5 angle, C5–C7 angle, and C2–C7 angle, T1 slope, center of gravity of the head to sagittal vertical axis (CG–C7 SVA, and local sagittal alignment (C0–C2 SVA and C2–C7 SVA. Results. McGS was significantly correlated to C0–C2 angle (r=0.57, C0–C2 SVA (r=−0.53, C2–C7 SVA (r=−0.28, and CG–C7 SVA (r=−0.47. CG–C7 SVA was also significantly correlated to curvature type (r=0.27, C5–C7 angle (r=−0.37, and C2–C7 angle (r=−0.39. Conclusions. A backward shift with an extended head position may accompany a relatively normal curvature of the cervical spine. The effect of posture control in relieving abnormal mechanical state of the cervical spine needs to be further confirmed by biomechanical analysis.

  14. Sagittal synostosis in X-linked hypophosphatemic rickets and related diseases

    Energy Technology Data Exchange (ETDEWEB)

    Currarino, Guido [Texas Scottish Rite Hospital, Department of Radiology, Dallas, TX (United States)

    2007-08-15

    The recent observations of two new cases of X-linked hypophosphatemic rickets associated with premature closure of the sagittal suture prompted a review of similar cases seen in this institution. To review the clinical records and skull radiographs of 28 children with hypophosphatemic rickets in order to investigate the frequency and type of craniosynostosis and other cranial vault changes seen in these conditions and to review the literature for relevant findings. Clinical and imaging records were reviewed on 28 patients with hypophosphatemic rickets, all younger than 18 years. Most patients had X-linked hypophosphatemic rickets and a few had autosomal-dominant hypophosphatemic rickets or were non-familial cases. Of the 28 patients, 13 had sagittal synostosis. Dolichocephaly was present in ten patients. The configuration of the cranial vault in some of these ten patients with dolichocephaly varied somewhat from that seen in nonsyndromic sagittal synostosis. In one patient, a Chiari I malformation was demonstrated by MRI. In another patient with increased intracranial pressure the sagittal suture closure was associated with lambdoidal synostosis. Dolichocephaly was not present in three patients, suggesting that the synostosis started later than in the other patients, probably in the second year of life, a period of slower brain growth than in the first year. The two patients in this group of three showed thickening and sclerosis of the cranial vault of uncertain etiology. There is an increased risk of sagittal synostosis in hypophosphatemic rickets and related diseases in children. The appearance of the cranial vault in this type of synostosis can vary from that seen in nonsyndromic synostosis. In this setting, careful clinical and imaging follow-up is warranted. (orig.)

  15. PARAMETERS FOR THE EVALUATION OF CERVICAL SAGITTAL BALANCE IN IDIOPATHIC SCOLIOSIS

    Directory of Open Access Journals (Sweden)

    MAURICIO COELHO LIMA

    Full Text Available ABSTRACT Objective: There are no values defined as standard in the literature for the parameters of assessment of cervical sagittal balance in patients with idiopathic scoliosis. This study describes the sagittal cervical parameters in patients with idiopathic scoliosis. Methods: Study carried out in a tertiary public hospital in patients with adolescent idiopathic scoliosis, through the evaluation of panoramic radiographs in lateral view. The Cobb method was used to evaluate cervical lordosis from C2 to C7, distance from the center of gravity (COG of the skull to C7, measurement of T1 slope, thoracic inlet angle (TIA, neck tilt, and plumb line from C7 to S1 (SVA C7-S1. A statistical analysis was performed, to demonstrate the relationship between the alignment of the thoracic spine in the sagittal plane and the cervical sagittal balance of patients with scoliosis. Results: Thirty-four patients were female (69.4% and 15 male (30.6%. The mean values for COG-C7 were 0.71 mm (median 0.8 mm/standard deviation [SD]= 0.51 mm. For Cobb C2-C7, the mean was -11.7° (median -10°/SD= 20.4°. The mean slope of T1 was 23.5° (median 25°/SD= 9.5°. The mean cervical version was 58.8° (median 60°/DP= 15.4°. The mean TIA was 81.8° (median 85°/SD= 16.7°. The mean plumb line C7-S1 was -0.28 (-0.3/SD= 1.0. Conclusion: The analysis of the results showed that the mean values for the cervical lordosis are lower than the values described as normal in the literature, suggesting a loss of sagittal cervical balance in these patients.

  16. UPFLOWS IN FUNNEL-LIKE LEGS OF CORONAL MAGNETIC LOOPS

    International Nuclear Information System (INIS)

    Tian Hui; Marsch, Eckart; Curdt, Werner; He, Jiansen

    2009-01-01

    The prominent blueshifts of Ne VIII associated with the junctions of the magnetic network in the quiet Sun are still not well understood. By comparing the coronal magnetic-field structures as obtained by a potential-field reconstruction with the conspicuous blueshift patches on the Dopplergram of Ne VIII as observed in an equatorial quiet-Sun region, we find that most of the regions with significant upflow are associated with the funnel-like legs of magnetic loops and cospatial with increments of the line width. These quasi-steady upflows can be regarded as the signatures of mass supply to coronal loops. By using the square root of the line intensity as a proxy for the plasma density, the mass flux of the upflow in each funnel can be estimated. We find that the mass flux is anti-correlated with the funnel's expansion factor as determined from the extrapolated magnetic field. One of the loop systems is associated with a coronal bright point, which was observed by several instruments and exhibited various morphologies in different wavelengths and viewing directions. A remarkable agreement between its magnetic structure and the associated EUV emission pattern was found, suggesting an almost potential-field nature of the coronal magnetic field. We also report the direct detection of a small-scale siphon flow by both STEREO satellites. However, this transient siphon flow occurred in a weak mixed-polarity-field region, which was outside the adjacent magnetic funnel, and thus it is perhaps not related to plasma upflow in the funnel. Based on these observations, we suggest that at upper transition region (TR) temperatures the dominant flows in quiet-Sun coronal loops are long-lasting upflows rather than siphon flows. We also discuss the implications of our results for coronal heating and unresolved magnetic structures.

  17. Multidetector CT of Locally Invasive Advanced Gastric Cancer: Value of Oblique Coronal Reconstructed Images for the Assessment of Local Invasion

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Jin Hee; Kim, Ah Yong; Kim, Hye Jin; Yook, Jeong Hwan; Yu, Eun Sil; Jang, Yoon Jin; Park, Seong Ho; Shin, Yong Moon; Ha, Hyun Kwon [Asan Medical Center, Seoul (Korea, Republic of)

    2010-01-15

    To evaluate the diagnostic value of oblique coronal reconstructed CT images to determine the local invasion of advanced gastric cancer (AGC). Thirty-four consecutive patients, who were suspected to have locally invasive advanced gastric cancer (more than T3 stage) on a preoperative MDCT scan and underwent a diagnostic or curative laparotomy, were enrolled in this study. Two reviewers performed an independent blind review of three series of MDCT images in random order; axial (AXI), conventional coronal (CCI), and oblique coronal (OCI) (parallel to long axis of gastric body and pancreas) images. In assessing the local invasion, the reader's confidence for the local invasion of AGC was graded using a five point scale (1 = definitely negative, 5 = definitely positive: T4). With surgical findings and histopathological proofs as reference standards, the diagnostic performance of the three different plans of CT images was employed for the verification of local invasion of AGC on a preoperative CT scan using the receiver operating characteristic (ROC) method. Agreements between the two reviewers were analyzed using weighted kappa statistics. Results: In 19 out of 34 patients, local invasion was confirmed surgically or histopathologically (13 pancreas invasion, 6 liver invasion, 4 major vascular invasion, 3 colon and mesocolon invasion, and 2 spleen invasion). The diagnostic performance of OCI was superior to AXI or CCI in the local invasion of AGC. The differences in the area under the curve of AXI (0.770 {+-} 0.087, 0.700 {+-} 0.094), CCI (0.884 {+-} 0.058, 0.958 {+-} 0.038), and OCI (0.954 {+-} 0.050, 0.956 {+-} 0.049), were statistically significant for both reviewers. Inter-observer agreement was excellent for OCI ({kappa}= .973), which was greater than CCI (({kappa}= .839), and AXI (({kappa}= .763). On a CT scan, OCI might be a useful imaging technique in evaluating locally invasive advanced gastric cancer.

  18. A thermal catastrophe in a resonantly heated coronal loop

    International Nuclear Information System (INIS)

    Martens, P.C.H.; Kuperus, M.

    1983-01-01

    A theory for the thermal stability of hot coronal loops is presented, which is based on the resonant electrodynamic heating theory of Ionson (1982) and the evaporation/condensation scenario of Krall and Antiochos (1980). The theory predicts that gradual changes in the length of a loop or in its magnetic field strength can trigger catastrophic changes in the X-ray visibility of the loop, without the need for a change in the magnetic field topology. A natural explanation is thereby given for the observations of X-ray brightenings in loops and loop evacuations with coronal rain. (Auth.)

  19. Coronal seismology waves and oscillations in stellar coronae

    CERN Document Server

    Stepanov, Alexander; Nakariakov, Valery M

    2012-01-01

    This concise and systematic account of the current state of this new branch of astrophysics presents the theoretical foundations of plasma astrophysics, magneto-hydrodynamics and coronal magnetic structures, taking into account the full range of available observation techniques -- from radio to gamma. The book discusses stellar loops during flare energy releases, MHD waves and oscillations, plasma instabilities and heating and charged particle acceleration. Current trends and developments in MHD seismology of solar and stellar coronal plasma systems are also covered, while recent p

  20. Vector and axial constants of the baryon decuplet

    International Nuclear Information System (INIS)

    Belyaev, V.M.; Blok, B.Y.; Kogan, Y.I.

    1985-01-01

    On the basis of the QCD sum rules for the polarization operator in external axial and vector fields we determine the vector and axial transition constants in the 3/2 + baryon decuplet. We show that the renormalization of the axial constant is due to the interaction of the external axial field with the quark condensate

  1. Nucleon axial form factor from lattice QCD

    International Nuclear Information System (INIS)

    Liu, K.F.; Dong, S.J.; Draper, T.; Wu, J.M.; Wilcox, W.

    1994-01-01

    Results for the isovector axial form factors of the proton from a lattice QCD calculation are presented for both the point-split and local currents. They are obtained on a quenched 16 3 x24 lattice at β=6.0 with Wilson fermions for a range of quark masses from strange to twice the charm mass. For each quark mass, we find that the axial form factor falls off slower than the corresponding proton electric form factor. Results extrapolated to the chiral limit show that the q 2 dependence of the axial form factor agrees quite well with experiment. The axial vector coupling constant g A calculated for the point-split and local currents is 1.20±0.11 and 1.18±0.11. The central values are 4% and 6% smaller than the experimental value of 1.254, respectively. We also consider the large ma correction and renormalization for the axial vector current of heavy quarks

  2. Optimization of residual heat removal pump axial thrust and axial bearing

    International Nuclear Information System (INIS)

    Schubert, F.

    1996-01-01

    The residual heat removal (RHR) pumps of German 1300 megawatt pressurized-water reactor (PWR) power plants are of the single stage end suction type with volute casing or with diffuser and forged circular casing. Due to the service conditions the pumps have to cover the full capacity range as well as a big variation in suction static pressure. This results in a big difference in the axial thrust that has to be borne by the axial bearing. Because these pumps are designed to operate without auxiliary systems (things that do not exist can not fail), they are equipped with antifriction bearings and sump oil lubrication. To minimize the heat production within the bearing casing, a number of PWR plants have pumps with combined axial/radial bearings of the ball type. Due to the fact that the maximum axial thrust caused by static pressure and hydrodynamic forces on the impeller is too big to be borne by that type of axial bearing, the impellers were designed to produce a hydrodynamic axial force that counteracts the static axial force. Thus, the resulting axial thrust may change direction when the static pressure varies

  3. Optimization of residual heat removal pump axial thrust and axial bearing

    Energy Technology Data Exchange (ETDEWEB)

    Schubert, F.

    1996-12-01

    The residual heat removal (RHR) pumps of German 1300 megawatt pressurized-water reactor (PWR) power plants are of the single stage end suction type with volute casing or with diffuser and forged circular casing. Due to the service conditions the pumps have to cover the full capacity range as well as a big variation in suction static pressure. This results in a big difference in the axial thrust that has to be borne by the axial bearing. Because these pumps are designed to operate without auxiliary systems (things that do not exist can not fail), they are equipped with antifriction bearings and sump oil lubrication. To minimize the heat production within the bearing casing, a number of PWR plants have pumps with combined axial/radial bearings of the ball type. Due to the fact that the maximum axial thrust caused by static pressure and hydrodynamic forces on the impeller is too big to be borne by that type of axial bearing, the impellers were designed to produce a hydrodynamic axial force that counteracts the static axial force. Thus, the resulting axial thrust may change direction when the static pressure varies.

  4. Wave propagation in axially moving periodic strings

    DEFF Research Database (Denmark)

    Sorokin, Vladislav S.; Thomsen, Jon Juel

    2017-01-01

    The paper deals with analytically studying transverse waves propagation in an axially moving string with periodically modulated cross section. The structure effectively models various relevant technological systems, e.g. belts, thread lines, band saws, etc., and, in particular, roller chain drives...... for diesel engines by capturing both their spatial periodicity and axial motion. The Method of Varying Amplitudes is employed in the analysis. It is shown that the compound wave traveling in the axially moving periodic string comprises many components with different frequencies and wavenumbers....... This is in contrast to non-moving periodic structures, for which all components of the corresponding compound wave feature the same frequency. Due to this "multi-frequency" character of the wave motion, the conventional notion of frequency band-gaps appears to be not applicable for the moving periodic strings. Thus...

  5. PLANIMETRIC CHARACTERISTICS OF CORPUS CALLOSUM SAGITTAL PROFILE IN MIDDLE- AND ADVANCED AGED MEN.

    Science.gov (United States)

    Boiagina, O; Kostilenko, Yu

    2017-10-01

    The sagittal profile of the corpus callosum is available for morphometric measurements of conditioned linear distances when elucidating its age-related changes and sexual dimorphism. But in this case, the opportunity to determine the total area of the sagittal profile of the corpus callosum is lost, while being a more full expression of its digital characteristics. We set the goal to establish the differences between planimetric indices of male corpus callosum of the first and second periods of adulthood and the advanced age. The work used 65 brain preparations of men aged 22 to 73 years who died for reasons unrelated to the pathology of the central nervous system. After a two-week fixation in a 10% solution of neutral formalin, the brain was dissected along the longitudinal sagittal fissure into two hemispheres, one of which was used to photograph its medial surface with an overlaid scale ruler. The received standardized photos were used to determine the basic metric parameters and conduct a planimetric study of the sagittal profile of the corpus callosum using the Adobe Photoshop CS6 Extended computer program. The overall evaluation of the results of planimetric analysis of the male corpus callosum sagittal profile we directed attention to the fact that within each age group there is a wide scatter of individual digital values of its area as well as random and irregular nature of their distribution that is completely independent of the intra-group age chronology. Thus, in the first period of adulthood, the minimum value of the area of the corpus callosum sagittal profile is 560 mm2, while the maximum value is 930 mm2 (the average statistical value is 747.5 ± 110.4 mm2). In the second period of adulthood, somewhat lower indicators are indicated; if the minimum value of it is equal to 412 mm2, then the maximum value is 868 mm2 (the average is 684.7 ± 130.0 mm2). In the advanced age, we find them in the range between 441 and 867 mm2 (the average value is 650.2

  6. Axial pico turbine - construction and experimental research

    Science.gov (United States)

    Peczkis, G.; Goryca, Z.; Korczak, A.

    2017-08-01

    The paper concerns axial water turbine of power equal to 1 kW. The example of axial water turbine constructional calculations was provided, as well as turbine rotor construction with NACA profile blades. The laboratory test rig designed and built to perform measurements on pico turbine was described. The turbine drove three-phase electrical generator. On the basis of highest efficiency parameters, pico turbine basic characteristics were elaborated. The experimental research results indicated that pico turbine can achieve maximum efficiency close to the values of larger water turbines.

  7. Axial Vircator for Electronic Warfare Applications

    Directory of Open Access Journals (Sweden)

    L. Drazan

    2009-12-01

    Full Text Available This paper deals with a high power microwave generator with virtual cathode – vircator in axial release for electronic warfare applications. The classification of directed energy weapons microwave (DEWM is introduced together with basic block diagrams of a particular class of DEWM. In the paper, methods for designing vircator pulsed power supply, axial vircator structure, measurement methods and experimental results are presented. The vircator in electromagnetic ammunition is powered by magneto-cumulative generator and in weapons for defense of objects (WDO, it is powered by Marx generator. The possible applications of a vircator in the DEWM area are discussed.

  8. Solar Wind Associated with Near Equatorial Coronal Hole M ...

    Indian Academy of Sciences (India)

    2015-05-25

    May 25, 2015 ... pute coronal hole radiative energy near the earth and it is found to be of similar order as that of ... hole and energy due to solar wind, it is conjectured that solar wind might have originated around the ..... velocity Vsw (assuming wind velocity is constant throughout from the source to the place of observation) ...

  9. Coronal Structures as Tracers of Sub-Surface Processes

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... The origin of the field is beneath the turbulent convection zone, where the magnetic field is not a master but a slave, and one can wonder how much the coronal magnetic field ``remembers" its dynamo origin. Surprisingly, it does. We will describe several observational phenomena that indicate a close ...

  10. Magnetic Field in the Gravitationally Stratified Coronal Loops B. N. ...

    Indian Academy of Sciences (India)

    field for the longest (L = 406 Mm) coronal loops. The magnetic fields Bstr and Babs also increase with the number density, if the loop length does not vary much. The increment in the magnetic field due to gravitational stratification is small at the lower number densities, however, it is large at the higher number densities.

  11. Numerical simulations of the solar corona and Coronal Mass Ejections

    NARCIS (Netherlands)

    Poedts, S.; Jacobs, C.; van der Holst, B.; Chane, E.; Keppens, R.

    2009-01-01

    Numerical simulations Of Coronal Mass Ejections (CMEs) call provide a deeper Insight ill the Structure and propagation of these impressive solar events. lit this work, we present our latest results Of numerical simulations of the initial evolution Of a fast CME. For this purpose, the equations Of

  12. Solar Coronal Plumes and the Fast Solar Wind

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... Before the spectroscopic peculiarities in IPRs and plumes in Polar Coronal Holes (PCHs) can be further investigated with the instrument Solar Ultraviolet Measurements of Emitted Radiation (SUMER) aboard the Solar and Heliospheric Observatory (SOHO), it is mandatory to summarize the results of the ...

  13. Oblique Propagation and Dissipation of Alfven Waves in Coronal ...

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... We investigate the effect of viscosity and magnetic diffusivity on the oblique propagation and dissipation of Alfvén waves with respect to the normal outward direction, making use of MHD equations, density, temperature and magnetic field structure in coronal holes and underlying magnetic funnels. We find ...

  14. Intermittent Coronal Loop Oscillations by Random Energy Releases

    Science.gov (United States)

    Mendoza-Briceño, César A.; Erdélyi, Robert

    2006-09-01

    High-resolution observations by the SOHO and TRACE spacecraft have confirmed the existence of coronal loop oscillations and waves. In a recent work, Mendoza-Briceño et al. studied the heating response of coronal plasma to energy pulses randomly distributed in time and space along coronal loops. In this paper we focus on the oscillatory patterns and other features, such as cool gas blobs traveling along the loop, during the evolution of spatiotemporal randomly heated flux tubes in the corona. The nature of these oscillatory patterns is investigated using wavelet analysis. Periodic features, such as wave packets, with periods of 150-220, 500-600, and 800-1000 s are found. It is also found that the periods increase with the loop length and decrease with the length of the loop segments along which the pulses are injected. On the other hand, the randomly driven intermittent cool plasma blobs that propagate from one footpoint to the other are analyzed. Although plenty of coronal loop oscillations are detected by the cohort of the current high-resolution satellites, there are more controversial observational evidences about the predicted cold plasma blobs.

  15. Photometric Variability of Four Coronally Active Stars J. C. Pandey ...

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    ray surveys with the Einstein and the ROSAT observatories and found to be associated with bright late- type stars. Many of these stars have not been studied in detail for their chromospheric and coronal activity, and their nature is not fully ...

  16. Analysis of Solar Coronal Holes with Synoptic Magnetogram Data

    Science.gov (United States)

    Canner, A.; Kim, T. K.; Pogorelov, N.; Yalim, M. S.

    2017-12-01

    Coronal holes are regions in which the magnetic field of the Sun is open with high magnetic flux and low plasma density. Because of the low plasma beta in these regions, the open field lines transport plasma from the Sun throughout the heliosphere. Coronal hole area is closely related to the expansion factor of the magnetic flux tube, as demonstrated by Tokumaru et al. (2017). Following the approach of Tokumaru et al. (2017), we employ a potential field source surface model to identify the open field regions on the photosphere and estimate the area and expansion factor for each coronal hole. While Tokumaru et al. (2017) analyzed synoptic maps from Kitt Peak National Observatory for the period 1995-2011, we use different magnetograph observations with higher spatial resolution (e.g., SOHO-MDI) for the same time period. We compare the coronal hole area - expansion factor relationship with the original results of Tokumaru et al (2017). This work was supported by the NSF-funded Research Experience for Undergraduates program "Solar and Heliospheric Physics at UAH and MSFC" run by the University of Alabama in Huntsville in partnership with the Marshall Space Flight Center through grant AGS-1460767.

  17. Heating coronal holes and accelerating the solar wind

    Science.gov (United States)

    Parker, E. N.

    1992-01-01

    The special energy requirements of a coronal hole combined with current knowledge of the limited dissipation of Alfven and fast mode MHD waves in the solar corona suggest a unique source of heat for the coronal hole. The near coronal hole requires approximately 3 - 4 x 10 exp 5 ergs/sq cm s, which can come only from the fluid jets, fast particles, and short period MHD waves from the network activity. The high speed streams of solar wind from coronal holes show that there is substantial heating, of 1 - 2 x 10 exp 5 ergs/sq cm s, beyond the sonic point in the wind, which can come only from the dissipation by thermal conduction of long period (approximately equal or greater than 100 sec) MHD waves from subphotospheric convection. Although the Alfven wave flux from the photosphere is generally taken for granted in the literature, we point out that it is a crucial phenomenon that has yet to be established on either a theoretical or observational scientific basis.

  18. African Culture and Communication Systems in the Coronation of ...

    African Journals Online (AJOL)

    African culture cannot be detached from the mode of communication of Africans. In this study, the writer examined the aspects of African culture communicated during the coronation of the 27th Ata Igala of Kogi State, North-central Nigeria. The study was motivated by the fact that the Ata, Idakwo Michael Ameh Oboni, rather ...

  19. Magnetic Field in the Gravitationally Stratified Coronal Loops B. N. ...

    Indian Academy of Sciences (India)

    crucial especially in the magnetic field measurement of longer and long-lived coro- nal structures. The negligence of this factor causes a large amount of uncertainty in the estimation of magnetic field. This result is very important in keeping with the view of the evolution of kink waves in gravitationally stratified coronal loops.

  20. Initiation and Propagation of Coronal Mass Ejections P. F. Chen

    Indian Academy of Sciences (India)

    it is still an open question whether the pre-CME structure should always possess a flux rope. Or, the so-called ... ejecta and the solar wind is, (3) the effect of prominence mass drainage, among others. The fourth issue is ... solar flares, Moreton waves, EIT waves and dimmings, transient coronal holes, etc. The fifth issue is ...

  1. Coronal Structures as Tracers of Sub-Surface Processes

    Indian Academy of Sciences (India)

    tribpo

    The corona - a tenuous portion of the solar upper atmosphere - was observed as early as 1063 ... is still open. Considering the possible processes that can affect the appearance of coronal structures, one can divide them into two categories: ones that take place above the ... The hemispheric helicity rule in the solar corona.

  2. Dissipation of Alfven waves in solar coronal arches

    International Nuclear Information System (INIS)

    1989-01-01

    It is shown that the slow motion of the feet of coronal arches lead to irregular magnetic fields and that Alfvan waves propagating in the irregular magnetic sturcture are dissipated though filamentation of the wave packet that generates short scales necessary for efficient dissipation. (author). 19 refs.; 3 figs

  3. Standing Slow MHD Waves in Radiatively Cooling Coronal Loops ...

    Indian Academy of Sciences (India)

    the individual and combined effects of radiation and thermal conduction are studied by displaying the analytical solution numerically. Our discussions and conclusions are presented in Section 5. 2. The model and governing equations. We model a straight coronal loop, in which the magnetic field is uniform and in.

  4. Distribution of Latitudes and Speeds of Coronal Mass Ejections in ...

    Indian Academy of Sciences (India)

    Coronal Mass Ejections (CMEs), known as the most energetic form of solar magnetic activity, are now ... from the CPA of the CME, assuming that CMEs propagate radially away from the solar source region .... and southern hemispheres (second panel,vertical bars) observed by SOHO/LASCO in cycle 23 from September ...

  5. Coronal Structures as Tracers of Sub-Surface Processes

    Indian Academy of Sciences (India)

    tribpo

    Stackplot of Yohkoh synoptic maps for 8 solar rotations (1851-1858). Each strip covers 360° in Carrington longitude and 0-20° in latitude in the northern hemisphere. Longitude runs from left (0°) to right (360°). Table 4. Coronal flux systems observed in 1991-1992. Table 4 lists size, a lifetime and chirality of several flux ...

  6. RADIOLOGICAL TIPS Coronal views of the paediatric mandibular ...

    African Journals Online (AJOL)

    Panoramic radiography is still recommended as first-line evaluation for mandibular fractures in children.[3] CTB imaging often extends to involve the upper mandible/mandibular condyle in the imaging field. Routine review of the mandibular condyle particularly on the coronal views is advocated to avoid overlooking such ...

  7. Microflares as Possible Sources for Coronal Heating Meera Gupta ...

    Indian Academy of Sciences (India)

    sity to very high intensity and has been found to be a very useful instrument to study microflares. We have ... are seen in Hα, soft and hard X-ray wavelengths and their temporal evolution resem- bles large flares. .... is in the slightly higher altitude (∼ 1–3 × 104 km) coronal loops and the accelerated electrons could heat the ...

  8. Solar Wind Associated with Near Equatorial Coronal Hole

    Indian Academy of Sciences (India)

    2016-01-27

    Jan 27, 2016 ... Present study probes temporal changes in the area and radiative flux of near equatorial coronal hole associated with solar wind parameters such as wind speed, density, magnetic field and temperature. Using high temporal resolution data from SDO/AIA for the two wave-lengths 193 Å and 211 Å, area and ...

  9. Merging of coronal and heliospheric numerical two dimensional MHD models

    Czech Academy of Sciences Publication Activity Database

    Odstrčil, Dušan; Linker, J. A.; Lionello, R.; Mikic, Z.; Riley, P.; Pizzo, J. V.; Luhmann, J. G.

    2002-01-01

    Roč. 107, A12 (2002), s. SSH14-1 - SSH14-11 ISSN 0148-0227 R&D Projects: GA AV ČR IAA3003003 Institutional research plan: CEZ:AV0Z1003909 Keywords : coronal mass ejection * interplanetary shock * numerical MHD simulation Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 2.245, year: 2002

  10. A Bayesian Approach to Period Searching in Solar Coronal Loops

    Energy Technology Data Exchange (ETDEWEB)

    Scherrer, Bryan; McKenzie, David [Montana State University, P.O. Box 173840 Bozeman, MT 59717-3840 (United States)

    2017-03-01

    We have applied a Bayesian generalized Lomb–Scargle period searching algorithm to movies of coronal loop images obtained with the Hinode X-ray Telescope (XRT) to search for evidence of periodicities that would indicate resonant heating of the loops. The algorithm makes as its only assumption that there is a single sinusoidal signal within each light curve of the data. Both the amplitudes and noise are taken as free parameters. It is argued that this procedure should be used alongside Fourier and wavelet analyses to more accurately extract periodic intensity modulations in coronal loops. The data analyzed are from XRT Observation Program 129C: “MHD Wave Heating (Thin Filters),” which occurred during 2006 November 13 and focused on active region 10293, which included coronal loops. The first data set spans approximately 10 min with an average cadence of 2 s, 2″ per pixel resolution, and used the Al-mesh analysis filter. The second data set spans approximately 4 min with a 3 s average cadence, 1″ per pixel resolution, and used the Al-poly analysis filter. The final data set spans approximately 22 min at a 6 s average cadence, and used the Al-poly analysis filter. In total, 55 periods of sinusoidal coronal loop oscillations between 5.5 and 59.6 s are discussed, supporting proposals in the literature that resonant absorption of magnetic waves is a viable mechanism for depositing energy in the corona.

  11. Microwave Enhancement in Coronal Holes: Statistical Properties Ν ...

    Indian Academy of Sciences (India)

    tribpo

    Coronal holes appear as deficit in X ray and EUV emissions as compared to the quiet. Sun, except for a narrow microwave band (0.3 to 2 cm) in which they appear brighter than the quiet Sun (see, e.g. Kosugi et al, 1986 and references therein). The enhance ment typically consists of diffuse and compact components with ...

  12. Measurement of coronal properties of Seyfert galaxies from ...

    Indian Academy of Sciences (India)

    2018-02-10

    Feb 10, 2018 ... ... Refresher Courses · Symposia · Live Streaming. Home; Journals; Journal of Astrophysics and Astronomy; Volume 39; Issue 1. Measurement of coronal properties of Seyfert galaxies from NuSTAR's hard X-ray spectrum. PRIYANKA RANI C. S. STALIN. Volume 39 Issue 1 February 2018 Article ID 15 ...

  13. A sheet-current approach to coronal-interplanetary modeling

    International Nuclear Information System (INIS)

    Yeh, T.; Pneuman, G.W.

    1977-01-01

    The most pertinent effect of the currents in the coronal-interplanetary space is their alteration of the magnetic topology to form configurations of open field lines. The important currents seem to be those in the neighborhoods of the interfaces between closed and open field lines or between oppositely directed open field lines in the coronal helmet-streamer structures. Thus, the coronal-interplanetary space may be regarded as being partitioned by current-sheets into several piecewise current-free regions. These current sheets overlie the photospheric neutral lines, where the vertical component of the magnetic field reverses its polarity on the solar surface. But, their locations and strengths are determined by force balance between the magnetic field and the gas pressure in the coronal-interplanetary space. Since the pressure depends on the flow velocity of the solar wind and the solar wind channels along magnetic flux tubes, there is a strong magnetohydrodynamic coupling between the magnetic field and the solar wind. The sheet-current approach presented in this paper seems to be a reasonable way to account for this complicated interaction. (Auth.)

  14. Solar Wind Associated with Near Equatorial Coronal Hole M ...

    Indian Academy of Sciences (India)

    2015-05-25

    May 25, 2015 ... Probably, during the early his- tory of solar system formation, strong solar wind might have played a dominant role. 355 .... (Atmospheric Imaging Assembly), we have considered near equatorial coronal hole data with 1 hour time ... thermal or kinetic energy of the solar wind? (iii) at what height in the solar ...

  15. Explaining Coronal Reduction: Prosodic Structure and Articulatory Posture.

    Science.gov (United States)

    Parrell, Benjamin; Narayanan, Shrikanth

    2018-02-08

    Consonant reduction is often treated as an allophonic process at the phonological planning level, with one production target (allophone) being substituted for another. We propose that, alternatively, reduction can be the result of an online process driven by prosodically conditioned durational variability and an invariant production target. We show that this approach can account for patterns of coronal stop (/t/, /d/, and /n/) production in both American English and Spanish. Contrary to effort-driven theories of reduction, we show that reduction does notdepend on changes to gestural stiffness. Moreover, we demonstrate how differences between and within a language in the particular articulatory postures used to produce different coronal stops automatically lead to reduction to what have normally been considered distinct allophones - coronal approximants ([ð̞]) and flaps ([ɾ]). In this way, our approach allows us to understand different outcomes of coronal stop reduction as the dynamic interaction of a single process (durationally driven undershoot) and variable spatial targets. We show that these patterns are reflected across a wide variety of languages, and show how alternative outcomes of reduction may fit within the same general framework. © 2018 S. Karger AG, Basel.

  16. Ultraviolet Spectroscopic Observations of Coronal Streamers in the ...

    Indian Academy of Sciences (India)

    These structures are bright because they are more dense than the background corona. Their higher densities are due to particle trapping by the large- scale coronal magnetic field. With the Ultraviolet Coronagraph Spectrometer (UVCS) onboard the Solar and Heliospheric Observatory (SOHO), we have made considerable.

  17. Automated Identification of Coronal Holes from Synoptic EUV Maps

    Science.gov (United States)

    Hamada, Amr; Asikainen, Timo; Virtanen, Ilpo; Mursula, Kalevi

    2018-04-01

    Coronal holes (CHs) are regions of open magnetic field lines in the solar corona and the source of the fast solar wind. Understanding the evolution of coronal holes is critical for solar magnetism as well as for accurate space weather forecasts. We study the extreme ultraviolet (EUV) synoptic maps at three wavelengths (195 Å/193 Å, 171 Å and 304 Å) measured by the Solar and Heliospheric Observatory/Extreme Ultraviolet Imaging Telescope (SOHO/EIT) and the Solar Dynamics Observatory/Atmospheric Imaging Assembly (SDO/AIA) instruments. The two datasets are first homogenized by scaling the SDO/AIA data to the SOHO/EIT level by means of histogram equalization. We then develop a novel automated method to identify CHs from these homogenized maps by determining the intensity threshold of CH regions separately for each synoptic map. This is done by identifying the best location and size of an image segment, which optimally contains portions of coronal holes and the surrounding quiet Sun allowing us to detect the momentary intensity threshold. Our method is thus able to adjust itself to the changing scale size of coronal holes and to temporally varying intensities. To make full use of the information in the three wavelengths we construct a composite CH distribution, which is more robust than distributions based on one wavelength. Using the composite CH dataset we discuss the temporal evolution of CHs during the Solar Cycles 23 and 24.

  18. Automated coronal hole identification via multi-thermal intensity segmentation

    Science.gov (United States)

    Garton, Tadhg M.; Gallagher, Peter T.; Murray, Sophie A.

    2018-01-01

    Coronal holes (CH) are regions of open magnetic fields that appear as dark areas in the solar corona due to their low density and temperature compared to the surrounding quiet corona. To date, accurate identification and segmentation of CHs has been a difficult task due to their comparable intensity to local quiet Sun regions. Current segmentation methods typically rely on the use of single Extreme Ultra-Violet passband and magnetogram images to extract CH information. Here, the coronal hole identification via multi-thermal emission recognition algorithm (CHIMERA) is described, which analyses multi-thermal images from the atmospheric image assembly (AIA) onboard the solar dynamics observatory (SDO) to segment coronal hole boundaries by their intensity ratio across three passbands (171 Å, 193 Å, and 211 Å). The algorithm allows accurate extraction of CH boundaries and many of their properties, such as area, position, latitudinal and longitudinal width, and magnetic polarity of segmented CHs. From these properties, a clear linear relationship was identified between the duration of geomagnetic storms and coronal hole areas. CHIMERA can therefore form the basis of more accurate forecasting of the start and duration of geomagnetic storms.

  19. Solar wind heavy ions from energetic coronal events

    International Nuclear Information System (INIS)

    Bame, S.J.

    1978-01-01

    Ions heavier than those of He can be resolved in the solar wind with electrostatic E/q analyzers when the local thermal temperatures are low. Ordinarily this condition prevails in the low speed solar wind found between high speed streams, i.e. the interstream, IS, solar wind. Various ions of O, Si and Fe are resolved in IS heavy ion spectra. Relative ion peak intensities indicate that the O ionization state is established in the IS coronal source regions at approx. 2.1 x 10 6 K while the state of Fe is frozen in at approx. 1.5 x 10 6 K farther out. Occasionally, anomalous spectra are observed in which the usually third most prominent ion peak, O 8+ , is depressed as are the Fe peaks ranging from Fe 12+ to Fe 7+ . A prominent peak in the usual Si 8+ position of IS spectra is self-consistently shown to be Fe 16+ . These features demonstrate that the ionization states were frozen in at higher than usual coronal temperatures. The source regions of these hot heavy ion spectra are identified as energetic coronal events including flares and nonflare coronal mass ejections. 24 references

  20. Restorative proctocolectomy: morphological and functional study with coronal CT.

    Science.gov (United States)

    Pizzamiglio, M; Catalano, C; Sarrantonio, A; Pavone, P; Pronio, A; Montesani, C; Ribotta, G; Passariello, R

    1996-01-01

    Restorative proctocolectomy with ileal pouch has become the surgical treatment of choice for patients with ulcerative colitis (UC) and familial polyposis of the colon. Defecography is the radiological technique commonly employed to obtain detailed information on function and morphology of the ileal pouch; it allows the direct visualization of the ileal pouch and the anal canal, but it does not provide the visualization of the pelvis. In all patients, computed tomography (CT) on coronal planes was performed to determine its possibilities as an alternative to defecography; 10 patients with UC submitted to restorative proctocolectomy and were examined. Coronal CT images provided a panoramic vision of the pelvis and demonstrated the morphology of the ileal pouch, the thickness of its walls, and its correlation with the surrounding tissues. Coronal CT also allowed the evaluation of the continence of ileo-anal and ileo-ileal anastomosis and the functional changes of the perineal muscles at rest and during squeezing. CT images acquired on coronal planes allows an easy and clear detection of the major postoperative complications, such as stenosis or dehiscences of the anastomosis, pelvic phlogosis, and fistulae.

  1. Development of coronal cementum in hypsodont horse cheek teeth.

    Science.gov (United States)

    Sahara, Noriyuki

    2014-04-01

    The horse is a grazing herbivore whose cheek teeth are hypsodon; that is, they possess long crowns that are completely covered by coronal cement at eruption. For elucidation of the sequential events in the formation of this coronal cementum in the mandibular horse cheek teeth, in the present study the lower 3rd permanent premolar teeth (PM4 ) from 3.5-, 4-, and 5-year-old horses were compared by using radiography, microcomputed tomography (Miro-CT), light microscopy (LM), and scanning electron microscopy (SEM). The present study clearly showed that prior to coronal cementogenesis tartrate-resistant acid phosphatase (TRAP)-positive odontoclasts resorbed on the enamel surface of the reserve crown in horse cheek tooth. Enamel resorption areas were relatively narrow, and started from the cuspal tips, and moved in the apical direction during tooth development. A primary cementum was initially deposited on the irregularly pitted enamel-cementum junction (ECJ) of the infolding and peripheral enamel. The infolding cementum filled grooves completely by the time of tooth eruption. On the other hand, in the peripheral cementum, the secondary and tertiary cementum layers were sequentially deposited on the primary cementum. These two cementum layers were sites for the insertion of the periodontal ligaments, and were continually laid down on the primary cementum coronally rather than apically throughout the life. The results of the present study suggest that the coronal cementum of horse cheek teeth is a multistructural and multifunctional tissue, meeting the requirements of its many different functions. Copyright © 2014 Wiley Periodicals, Inc.

  2. FAST CONTRACTION OF CORONAL LOOPS AT THE FLARE PEAK

    International Nuclear Information System (INIS)

    Liu Rui; Wang Haimin

    2010-01-01

    On 2005 September 8, a coronal loop overlying the active region NOAA 10808 was observed in TRACE 171 A to contract at ∼100 km s -1 at the peak of an X5.4-2B flare at 21:05 UT. Prior to the fast contraction, the loop underwent a much slower contraction at ∼6 km s -1 for about 8 minutes, initiating during the flare preheating phase. The sudden switch to fast contraction is presumably corresponding to the onset of the impulsive phase. The contraction resulted in the oscillation of a group of loops located below, with the period of about 10 minutes. Meanwhile, the contracting loop exhibited a similar oscillatory pattern superimposed on the dominant downward motion. We suggest that the fast contraction reflects a suddenly reduced magnetic pressure underneath due either to (1) the eruption of magnetic structures located at lower altitudes or to (2) the rapid conversion of magnetic free energy in the flare core region. Electrons accelerated in the shrinking trap formed by the contracting loop can theoretically contribute to a late-phase hard X-ray burst, which is associated with Type IV radio emission. To complement the X5.4 flare which was probably confined, a similar event observed in SOHO/EIT 195 A on 2004 July 20 in an eruptive, M8.6 flare is briefly described, in which the contraction was followed by the expansion of the same loop leading up to a halo coronal mass ejection. These observations further substantiate the conjecture of coronal implosion and suggest coronal implosion as a new exciter mechanism for coronal loop oscillations.

  3. The Specific Sagittal Magnetic Resonance Imaging of Intradural Extra-Arachnoid Lumbar Disc Herniation

    Directory of Open Access Journals (Sweden)

    Tatsuro Sasaji

    2012-01-01

    Full Text Available Intradural extra-arachnoid lumbar disc herniation is a rare disease. Few MRI findings have been reported. We experienced an intradural extra-arachnoid lumbar disc herniation. We reviewed the preoperative MRI findings. Lumbar spine T2-weighted sagittal MRI showed that one line of the ventral dura was divided into two by a disc herniation. We speculated that the two lines comprised the dura and arachnoid and that a disc herniation existed between them. We believe that division of the ventral dural line on T2-weighted sagittal images is a characteristic finding of intradural extra-arachnoid lumbar disc herniation. The division of ventral dural line seemed to be a “Y,” and, thus, we called it the “Y sign.” The “Y sign” may be useful for diagnosing intradural extra-arachnoid lumbar disc herniation.

  4. The Specific Sagittal Magnetic Resonance Imaging of Intradural Extra-Arachnoid Lumbar Disc Herniation

    Science.gov (United States)

    Sasaji, Tatsuro; Horaguchi, Kiyoshi; Yamada, Noboru; Iwai, Kazuo

    2012-01-01

    Intradural extra-arachnoid lumbar disc herniation is a rare disease. Few MRI findings have been reported. We experienced an intradural extra-arachnoid lumbar disc herniation. We reviewed the preoperative MRI findings. Lumbar spine T2-weighted sagittal MRI showed that one line of the ventral dura was divided into two by a disc herniation. We speculated that the two lines comprised the dura and arachnoid and that a disc herniation existed between them. We believe that division of the ventral dural line on T2-weighted sagittal images is a characteristic finding of intradural extra-arachnoid lumbar disc herniation. The division of ventral dural line seemed to be a “Y,” and, thus, we called it the “Y sign.” The “Y sign” may be useful for diagnosing intradural extra-arachnoid lumbar disc herniation. PMID:22431932

  5. Influence of implant rod curvature on sagittal correction of scoliosis deformity

    DEFF Research Database (Denmark)

    Salmingo, Remel A.; Tadano, Shigeru; Abe, Yuichiro

    2014-01-01

    scoliosis patients underwent surgery. Average age at the time of operation was 14 years. OUTCOME MEASURES: The preoperative and postoperative implant rod angle of curvature expressed in degrees was obtained for each patient. METHODS: Two implant rods were attached to the concave and convex side...... of curvature between the implant rod extreme ends was measured before implantation and after surgery. The sagittal curvature between the corresponding spinal levels of healthy adolescents obtained by previous studies was compared with the implant rod angle of curvature to evaluate the sagittal curve correction...... significantly deformed after surgery. The average degree of rod deformation Dq at the concave and convex sides was 15.8 and 1.6, respectively. The average preoperative and postoperative implant rod angle of curvature at the concave side was 33.6 and 17.8, respectively. The average preoperative and postoperative...

  6. Craniofacial characteristics in the sagittal dimension: A cephalometric study in Lebanese young adults.

    Science.gov (United States)

    Daraze, Antoine; Delatte, Myriam; Bou Saba, Sami; Majzoub, Zeina

    2017-03-01

    The purpose of this study was to assess the sagittal cephalometric characteristics of young adult Lebanese individuals and assess gender-related differences. Conventional lateral cephalograms were obtained from 117 subjects. Eight linear/angular measurements combining sagittal parameters selected form McNamara and Steiner analyses were recorded. Paired t-test was applied to evaluate differences between genders and skeletal classes. Males showed significantly greater maxillary and mandibular length than females. ANB was larger in females with no significant differences in SNA values indicating that Lebanese females tend to have a more convex profile than their male counterparts. Subjects with skeletal Class III tended to have a retrognathic maxilla rather than a prognathic mandible. Sexual dimorphism is evident in young Lebanese adults relative to linear skeletal dimensions regardless of the skeletal class. Skeletal determinants of Class III malocclusions may be different from those of other population groups. Copyright © 2016 CEO. Published by Elsevier Masson SAS. All rights reserved.

  7. Sagittal synostosis: II. Cranial morphology and growth after the modified pi-plasty

    DEFF Research Database (Denmark)

    Guimaraes-Ferreira, J.; Gewalli, F.; David, L.

    2006-01-01

    The aim of this study was to characterise the postoperative cranial growth and morphology after a modified pi-plasty for sagittal synostosis. The shape of the skull of 82 patients with isolated premature synostosis of the sagittal suture ( SS group) operated on with a modified pi-plasty was studied...... developed by Kreiborg, which included the digitisation of 89 landmarks of the calvaria, cranial base, and orbit ( 43 in the lateral and 46 in the frontal projections), the production of mean shape plots for each group, and the intergroup comparison of a series of 78 variables ( linear distance between...... selected landmarks, and angles defined by groups of three landmarks). Paired and unpaired t tests were used to assess the differences between the variables studied. These were accepted as significant for values of p...

  8. A Review Of Referral Patterns For Sagittal Synostosis In Ireland: 2008-2013

    LENUS (Irish Health Repository)

    Berney, M J

    2018-01-01

    Sagittal synostosis (SS) is the commonest form of craniosynostosis. Children with sagittal synostosis in Ireland are treated in the National Paediatric Craniofacial Centre (NPCC) in Temple Street Children’s University Hospital. This retrospective study analysed the correlation between referral patterns to the unit and age at operation. The notes of 81 patients referred over a 5 year period (April 2008 – April 2013) to the NPCC with non-syndromic SS were reviewed and demographics and referral information were recorded. Of 81 patients reviewed, 60 (74%) were referred before 6 months of age, while 21 (26%) had late referrals. Neonatologists referred 100% of infants before 6 months, paediatricians referred 71%, and GPs 64%. Later referral was associated with a more complex referral pathway, including multiple-steps of referral and unnecessary investigations. Improved clinician knowledge and emphasis on the importance of early referral may lead to a reduction in late referrals.

  9. Sagittal crystal focusing of undulator radiation with high heat load inclined crystals

    International Nuclear Information System (INIS)

    Ice, G.E.; Sparks, C.J.

    1992-01-01

    Sagittal focusing of undulator radiation is shown to be compatible with the proposed inclined double-crystal monochromator geometry for heat load reduction. The focusing aberrations are found to be negligible for typical undulator-beam divergences over a range of magnifications from 1:2 to 6:1 and energies from 3 to 40 keV. The inclined geometry reduces the required signal sagittal curvature of the focusing crystal compared to focusing with conventional symmetric crystals; hence, focusing is possible at higher X-ray energies and with less anticlastic bending. In addition, anticlastic stiffening ribs project a smaller footprint to the beam so that the achievable focal spot size is potentially better than with conventional symmetrically cut crystals. 16 refs

  10. Evaluation of Knee Donor and Elbow Recipient Sites for Osteochondral Autologous Transplantation Surgery in Capitellar Osteochondritis Dissecans.

    Science.gov (United States)

    Vezeridis, Alexander M; Bae, Donald S

    2016-02-01

    Osteochondral autologous transplantation surgery (OATS) has been advocated for treatment of osteochondritis dissecans (OCD) of the capitellum in adolescents. However, little information is available regarding the optimal knee harvest site to match the contour and cartilage thickness of the recipient elbow lesion. To characterize the capitellar anatomic structure in adolescents with and without OCD and to compare these measurements to normal adolescent knees to identify the optimal site for osteochondral graft harvest. Controlled laboratory study. Twenty-one patients with OCD were analyzed. Twenty-two patients with normal elbows and 25 age-, weight-, and height-matched patients with normal knees were also identified. Cartilage radii of curvatures (ROCs) in the sagittal and coronal-axial planes were measured on magnetic resonance imaging (MRI) of normal capitella and 5 sites (posterior lateral femoral condyle, medial and lateral middle trochlear ridges, and medial and lateral inferior trochlear ridges) in normal knees. Differences in ROC between the knee donor and capitellar recipient sites were calculated based on a 10-mm osteochondral plug diameter. Overall, the mean apex differences between graft and recipient sites ranged from 0.4 to 0.9 mm, and mean edge differences ranged from 0.5 to 1.4 mm in the coronal-axial dimension. Of all knee sites tested, the posterior lateral femoral condyle had average ROCs (19.1 mm sagittal; 14.1 mm axial) most like the capitellum (10.6 mm sagittal, 12.6 mm coronal-axial), resulting in minimal apex and edge differences (apex difference = -0.6 mm; coronal-axial side difference = -0.5 mm; no sagittal side difference). Of the anterior nonweightbearing sites, the inferior medial trochlear ridge (28.3 mm sagittal ROC; 13.2 mm coronal-axial ROC) demonstrated the lowest apex and side differences when compared with the capitellum (apex difference = -0.8 mm; coronal-axial side difference = -0.8 mm; no sagittal side difference). The

  11. Is Postoperative Intensive Care Unit Care Necessary following Cranial Vault Remodeling for Sagittal Synostosis?

    Science.gov (United States)

    Wolfswinkel, Erik M; Howell, Lori K; Fahradyan, Artur; Azadgoli, Beina; McComb, J Gordon; Urata, Mark M

    2017-12-01

    Of U.S. craniofacial and neurosurgeons, 94 percent routinely admit patients to the intensive care unit following cranial vault remodeling for correction of sagittal synostosis. This study aims to examine the outcomes and cost of direct ward admission following primary cranial vault remodeling for sagittal synostosis. An institutional review board-approved retrospective review was undertaken of the records of all patients who underwent primary cranial vault remodeling for isolated sagittal craniosynostosis from 2009 to 2015 at a single pediatric hospital. Patient demographics, perioperative course, and outcomes were recorded. One hundred ten patients met inclusion criteria with absence of other major medical problems. Average age at operation was 6.7 months, with a mean follow-up of 19.8 months. Ninety-eight patients (89 percent) were admitted to a general ward for postoperative care, whereas the remaining 12 (11 percent) were admitted to the intensive care unit for preoperative or perioperative concerns. Among ward-admitted patients, there were four (3.6 percent) minor complications; however, there were no major adverse events, with none necessitating intensive care unit transfers from the ward and no mortalities. Average hospital stay was 3.7 days. The institution's financial difference in cost of intensive care unit stay versus ward bed was $5520 on average per bed per day. Omitting just one intensive care unit postoperative day stay for this patient cohort would reduce projected health care costs by a total of $540,960 for the study period. Despite the common practice of postoperative admission to the intensive care unit following cranial vault remodeling for sagittal craniosynostosis, the authors suggest that postoperative care be considered on an individual basis, with only a small percentage requiring a higher level of care. Therapeutic, III.

  12. Evaluation of the Sagittal Saw Blade as an Intraoperative Fomite During Diabetic Foot Surgery.

    Science.gov (United States)

    Creech, Corine L; Malan, Jared R; Meyr, Andrew J

    2015-08-01

    Surgical site infection is a major potential complication of all operative interventions, and the diabetic foot is particularly at risk for bacterial recontamination and infectious sequelae. The objective of this study was to identify whether the sagittal saw blade used during partial foot amputations and diabetic foot debridements carries the potential to serve as a bacterial fomite. We physically cultured the sagittal saw blade during 20 foot debridements involving the resection of bone in patients diagnosed with a diabetic foot infection. The culture was taken after the initial debridement and during the irrigation phase of the procedure. We observed 16 positive routine intraoperative culture results, with positive saw blade culture results in 15 (93.8%; 15/16) of these cases. In 14 (93.3%; 14/15) of these cases, the saw blade culture grew at least one of the same bacteria as our other routine intraoperative cultures. We observed 4 negative routine intraoperative culture results, with negative saw blade culture results in 3 (75.0%; 3/4) of these cases. This results in agreement between routine intraoperative cultures and saw blade culture of 85.0% (17/20). The results of this investigation demonstrate that the sagittal saw blade used for osseous resection during diabetic foot debridements and partial foot amputations carries the potential for intraoperative bacterial transmission. We recommend changing at least the sagittal saw blade if more bone is resected following irrigation, particularly if it is used to obtain a "clean margin" for microbiological or histological examination. Therapeutic, Level IV: Case series. © 2014 The Author(s).

  13. The Specific Sagittal Magnetic Resonance Imaging of Intradural Extra-Arachnoid Lumbar Disc Herniation

    OpenAIRE

    Sasaji, Tatsuro; Horaguchi, Kiyoshi; Yamada, Noboru; Iwai, Kazuo

    2012-01-01

    Intradural extra-arachnoid lumbar disc herniation is a rare disease. Few MRI findings have been reported. We experienced an intradural extra-arachnoid lumbar disc herniation. We reviewed the preoperative MRI findings. Lumbar spine T2-weighted sagittal MRI showed that one line of the ventral dura was divided into two by a disc herniation. We speculated that the two lines comprised the dura and arachnoid and that a disc herniation existed between them. We believe that division of the ventral du...

  14. 3 Dimensional Plate in Management of Sagittal Palatal Fracture: A Novel Technique.

    Science.gov (United States)

    Rai, Anshul

    2017-12-01

    The palatal fracture is rare. There are varieties of techniques mentioned in the literature for fixation of palatal fracture. The management with Kirschner wire fixation, maxillary arch stabilization with the arch bars, trans-palatal, intra osseous, inter-molar, figure of eight wiring were technique sensitive and having poor patient compliance. We recommended the use of isolated 3 dimensional plate for fixation of sagittal palatal fracture.

  15. Sagittal fractures of the third carpal bone in horses: 12 cases (1977-1985)

    International Nuclear Information System (INIS)

    Fischer, A.T. Jr.; Stover, S.M.

    1987-01-01

    Third carpal sagittal fractures were found to be related to racing injuries in 10 of 12 horses. These fractures occurred most commonly on the medial aspect of the bone. A dorsoproximal-dorsodistal view of the carpus was required to visualize the fracture in all cases. Healing of the fracture required periods of rest of up to one year. Conservative management of these fractures resulted in return to function in 7 of 12 horses

  16. Correlation of Dental and Skeletal Malocclusions in Sagittal Plane among Saudi Orthodontic Patients.

    Science.gov (United States)

    Al-Hamlan, Nasir; Al-Eissa, Balsam; Al-Hiyasat, Ahmad S; Albalawi, Farraj S; Ahmed, Anwar E

    2015-05-01

    Whether or not the dental relationship correlates with skeletal relationship in the sagittal plane is an area of interest for orthodontic diagnosis and treatment planning. Thus, the aim of this study was to investigate the correlation of the dental malocclusion and the skeletal malocclusion in the sagittal plane among Saudi orthodontic patients. Orthodontic dental casts and cephalometric radiographs of 124 patients were investigated and analyzed. The dental casts were classified in relation to the molar relationship according to Angle's classification and to the incisal relationship according to the British Standards Institution (BSI) classification. The sagittal relation in the cephalometric radiographs was analyzed according to ANB angle and WITS appraisal. The results show that the incisal relation had a very high significant association with WITS appraisal (p = 0.0045), whereas with ANB, the association was marginally significant (p =0.0528). No significant associations were found with molar relation neither at ANB (p = 0.2075) nor at the WITS (p = 0.4794) appraisal. Significant positive correlations between ANB and WITS appraisal were found at the three incisal classification classes (class I, r = 0.73; class II, r = 0.64; class III, r = 0.75) and no significant correlation was observed in all classes with the Angle's (molar) classification. The incisal classification had a significant association with WITS appraisal, whereas with ANB the association was marginally significant. No correlation was found between Angle's (molar) classification and ANB or WITS appraisal. The incisal relation could be considered as a good indicator of the skeletal malocclusion in the sagittal plane in the orthodontic practice.

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

    OpenAIRE

    Letti,Helen Carolina Becker; Rizzatto,Susana Maria Deon; Menezes,Luciane Macedo de; Reale,Chalana Sangalli; Lima,Eduardo Martinelli de; Martinelli,Fernando Lima

    2013-01-01

    OBJECTIVE: The objective of this study was to evaluate a sagittal variation on the lower incisors with the use of the lingual arch on the transition from mixed to permanent dentition. METHODS: The sample was constituted of 44 Caucasian patients (26 girls and 18 boys), divided in two groups: CG, control group, monitoring the lower arch space with no orthodontic/orthopedic treatment during the rated period (n = 14); EG, experimental group, presenting anterior inferior mild crowding and installa...

  18. Current concepts on the sagittal balance and classification of spondylolysis and spondylolisthesis ? ??

    OpenAIRE

    Tebet, Marcos Antonio

    2014-01-01

    Treatment of spondylolysis and spondylolisthesis remains a challenge for orthopaedic surgeons, neurosurgeons and paediatrics. In spondylolisthesis, it has been clearly demonstrated over the past decade that spino-pelvic morphology is abnormal and that it can be associated to an abnormal sacro-pelvic orientation as well as to a disturbed global sagittal balance of spine. This article presents the SDSG (Spinal Deformity Study Group) classification of lumbosacral spondylolisthesis. The proper tr...

  19. Sagittal abdominal diameter shows better correlation with cardiovascular risk factors than waist circumference and BMI

    OpenAIRE

    de Souza, Natalia Cavalheri; de Oliveira, Erick Prado

    2013-01-01

    Background Obesity (abdominal adiposity) is a risk factor for cardiovascular diseases and the most used methods to measure the adiposity are body mass index (BMI), waist circumference (WC), and sagittal abdominal diameter (SAD). Objective To correlate BMI, WC, and SAD with biochemical parameters and blood pressure in adults. Methods A non-experimental exploratory/descriptive and cross sectional study was developed and it was assessed 133 subjects (59 men and 74 women) aging between 18 and 87?...

  20. The effect of neurocranial surgery on basicranial morphology in isolated sagittal craniosynostosis.

    Science.gov (United States)

    DeLeon, V B; Zumpano, M P; Richtsmeier, J T

    2001-03-01

    Isolated sagittal craniosynostosis produces a scaphocephalic neurocranium associated with abnormal basicranial morphology, providing additional evidence of the developmental relationship of the neurocranium and basicranium. Corrective surgical procedures vary, but the immediate impact of the surgical procedure is restricted to the neurocranium. This study addresses the secondary effects of neurocranial surgery on the cranial base. Three-dimensional (3-D) computed tomography (CT) scans were obtained for preoperative (n = 25) and postoperative (n = 12) patients with isolated sagittal synostosis. Landmark data from 14 landmarks on and around the cranial base were collected from 3-D CT reconstructions and analyzed using Euclidean distance matrix analysis. Subsamples of age-matched patients were used to identify basicranial differences in pre- and postoperative patients and to compare postoperative growth patterns identified in longitudinal data with preoperative growth patterns characterized in cross-sectional data. Statistically significant differences (p asterion, and left asterion are similar in preoperative and postoperative patients. However, the position of these landmarks relative to the cranial base is different in the two groups, being positioned relatively more anteriorly in postoperative patients. In addition, we found that the cranial base angle, on average, neither increases nor decreases in the first postoperative year. These morphological differences are associated with divergent growth trajectories in the operated and unoperated cranial base. Regardless of specific procedure, neurocranial surgery in sagittal synostosis patients affects growth patterns of the cranial base. The lack of change in the postoperative cranial base angle suggests that neurocranial surgery alleviates the occipital rotation and decreased cranial base angle described in the sagittal synostosis basicranium.

  1. Determination of craniofacial relation among the subethnic Indian population: A modified approach - (Sagittal relation

    Directory of Open Access Journals (Sweden)

    A Sumathi Felicita

    2012-01-01

    Full Text Available Aim : To measure the linear cephalometric dimensions of anterior and posterior segments of the craniofacial complex sagittally, to establish ratios between different linear dimensions of sagittal segments and check for dimensional balance among the various segments in subjects with normal occlusion, pleasing profile and facial harmony. Setting and Sample Population : Department of Orthodontics, Saveetha University. Lateral cephalograms of 120 subjects of both sexes in the age group of 17-28 years with normal occlusion belonging to Chennai, India Materials and Methods : Linear dimensions of anterior and posterior segments of the craniofacial complex were measured sagittally with the posterior maxillary plane as a key reference plane. Ratios were established between the various parameters in the anterior and posterior region. Results : A ratio of 1:1 was found to exist between the individual and aggregate sagittal segments of the craniofacial complex in both sexes. There was a statistically significant sexual dimorphism in the aggregate lengths(P=0.028,P=0.005.However, the ratio between the anterior cranial floor and effective maxillary length was 2:3 and 5:8 and that between anterior cranial floor to effective mandibular length was 5:8 and 3:5 in females and males respectively. The difference in the above values was not statistically significant. Conclusion : A dimensional balance was found to exist between the maxilla and mandible both at the dentoalveolar and skeletal level with a ratio of 1:1. There was also a dimensional balance between the posterior cranial floor and ramus width. However, there was no architectural balance between the anterior cranial floor and maxilla and mandible.

  2. Evaluation of palatal rugae pattern in different sagittal skeletal relationship adolescent subjects

    OpenAIRE

    Oral, Ekrem; Buyuk, S. Kutalmi?; Simsek, Huseyin

    2017-01-01

    Abstract The purpose of this study was to evaluate the morphological structure of palatal rugae in Turkish orthodontic subjects with different sagittal skeletal malocclusions. Orthodontic dental casts of 105 patients (Class I [23 females, 12 males]; 35, Class II [18 females, 17 males]; and 35, Class III [14 females, 21 males] 10?22 years old) were analyzed for rugae patterns. Palatal rugae pattern and number, direction of rugae alignment, shape of incisive papilla were analyzed. Modified Thom...

  3. Does Shoe Collar Height Influence Ankle Joint Kinematics and Kinetics in Sagittal Plane Maneuvers?

    Science.gov (United States)

    Yang, Yang; Fang, Ying; Zhang, Xini; He, Junliang; Fu, Weijie

    2017-12-01

    The Objective of the study is to investigate the effects of basketball shoes with different collar heights on ankle kinematics and kinetics and athletic performance in different sagittal plane maneuvers. Twelve participants who wore high-top and low-top basketball shoes (hereafter, HS and LS, respectively) performed a weight-bearing dorsiflexion (WB-DF) maneuver, drop jumps (DJs), and lay-up jumps (LJs). Their sagittal plane kinematics and ground reaction forces were recorded using the Vicon motion capture system and Kistler force plates simultaneously. Moreover, ankle dorsiflexion and plantarflexion angles, moment, power, stiffness, and jump height were calculated. In the WB-DF test, the peak ankle dorsiflexion angle (p = 0.041) was significantly smaller in HS than in LS. Additionally, the peak ankle plantarflexion moment (p = 0.028) and power (p = 0.022) were significantly lower in HS than in LS during LJs but not during DJs. In both jumping maneuvers, no significant differences were found in the jump height or ankle kinematics between the two shoe types. According to the WB-DF test, increasing shoe collar height can effectively reduce the ankle range of motion in the sagittal plane. Although the HS did not restrict the flexion-extension performance of the ankle joint during two jumping maneuvers, an increased shoe collar height can reduce peak ankle plantarflexion moment and peak power during the push-off phase in LJs. Therefore, a higher shoe collar height should be used to circumvent effects on the partial kinetics of the ankle joint in the sagittal plane.

  4. [Analysis of variation of sagittal position of the jaw bones in skeletal Class III malocclusion].

    Science.gov (United States)

    Stojanović, Zdenka; Nikolić, Predrag; Nikodijević, Angelina; Milić, Jasmina; Duka, Milos

    2012-12-01

    Skeletal Class III malocclusion is a discrepancy in the sagittal jaw relationship, due to imbalances in their development and/or position, resulting in the dominant appearance of the lower jaw in facial profile. The aim of this study was to determine variations in the sagittal position of the jaw bones to the cranial base in subjects with skeletal Class III, for the earliest possible diagnosis of malocclusion. Fifty children and as many adults with skeletal Class III, both sexes, were examined and selected, based on the findings of sagittal interjaw relationship (ANB) children aged 6-12 years, and another group, of adults aged 18-26 years. We measured the angles of maxillary prognathism (SNA), mandibular prognathism (SNB) and ANB. Based on these results, within the respective groups subclassification into the subgroups was done, among which a significant difference measured values was evaluated. In both groups a significant correlation of the determined values was evaluated. An average SNA angle ranged 77.36 +/- 3.58 in children and 77.32 +/- 4.88 in adults, while an average SNB angle was 79.46 +/- 3.91 in the group of children and 81.12 +/- 3.76 in adults. An average ANB angle was -2.10 +/- 2.07 in children, and -4.00 +/- 2.34 in adults. In both groups, a significant correlation between the measured values and a significant difference in the values of all the measured parameters were found between patients from different subgroups (p children and adults. Sagittal position of the lower jaw in most of the adults was prognathic, while mandible prognathism in the children was less present.

  5. Correlation between sagittal plane changes and adjacent segment degeneration following lumbar spine fusion

    OpenAIRE

    Kumar, Malhar; Baklanov, Andrei; Chopin, Daniel

    2001-01-01

    Adjacent segment degeneration following lumbar spine fusion remains a widely acknowledged problem, but there is insufficient knowledge regarding the factors that contribute to its occurrence. The aim of this study is to analyse the relationship between abnormal sagittal plane configuration of the lumbar spine and the development of adjacent segment degeneration. Eighty-three consecutive patients who underwent lumbar fusion for degenerative disc disease were reviewed retrospectively. Patients ...

  6. Demonstration of superior sagittal sinus thrombosis by indium-111 platelet scintigraphy

    Energy Technology Data Exchange (ETDEWEB)

    Bridgers, S.L.; Strauss, E.; Smith, E.O.; Reed, D.; Ezekowitz, M.D.

    1986-10-01

    Superior sagittal sinus thrombosis, documented by cerebral angiography, was demonstrated by indium-111 platelet scintigraphy in a 40-year-old man presenting with seizures and intracerebral hematoma. Early scintigraphy demonstrated focal increased indium-111 activity at the two ends of the thrombus, while later scintigraphy showed diffuse increased activity in the area of the sinus. This initial experience suggests that platelet scintigraphy may provide unique information regarding the natural history of intracranial venous thrombosis.

  7. Axial crystals macroscopic symmetry and tensor properties

    Czech Academy of Sciences Publication Activity Database

    Janovec, Václav

    2017-01-01

    Roč. 90, č. 1 (2017), s. 1-10 ISSN 0141-1594 Institutional support: RVO:68378271 Keywords : axial * polar * pseudopolar * chiral * enantiomorphism * optical activity Subject RIV: BM - Solid Matter Physics ; Magnetism OBOR OECD: Condensed matter physics (including formerly solid state physics, supercond.) Impact factor: 1.060, year: 2016

  8. Optimisation of efficiency of axial fans

    NARCIS (Netherlands)

    Kruyt, Nicolaas P.; Pennings, P.C.; Faasen, R.

    2014-01-01

    A three-stage research project has been executed to develop ducted axial-fans with increased efficiency. In the first stage a design method has been developed in which various conflicting design criteria can be incorporated. Based on this design method, an optimised design has been determined

  9. The design of axial shaftless pump

    Science.gov (United States)

    Schmirler, Michal; Netrebska, Hana

    The axial shaftless pump with a rotary casing has been proposed. The pump is unique in its small space requirements and the ability to draw a liquid with a high content of impurities and fibers. Modern motor with an external commutation was used to propel the pump rotor. The pump can be used for both pumping of liquids and marine propulsion.

  10. VERY SLOW SPEED AXIAL MOTION RELUCTANCE MOTOR

    African Journals Online (AJOL)

    Dr Obe

    1984-09-01

    Sep 1, 1984 ... VERY SLOW SPEED AXIAL MOTION RELUCTANCE MOTOR by. L. A. Agu. Electrical Engineering Department. University of Nigeria, Nsukka. ABSTRACT. This paper presents the scheme for a very slow speed linear machine which uses conventional laminations and with which speeds of the same low.

  11. Aryabha~ and Axial Rotation of Earth

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 11; Issue 4. Aryabhata and Axial Rotation of Earth - Naksatra Dina (the Sidereal Day). Amartya Kumar Dutta. General Article Volume 11 Issue 4 April 2006 pp 56-74. Fulltext. Click here to view fulltext PDF. Permanent link:

  12. Aryabhala and Axial Rotation of Earth

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 11; Issue 3. Aryabhata and Axial Rotation of Earth - Khagola (The Celestial Sphere). Amartya Kumar Dutta. General Article Volume 11 Issue 3 March 2006 pp 51-68. Fulltext. Click here to view fulltext PDF. Permanent link:

  13. The axial polarizability of nucleons and nuclei

    International Nuclear Information System (INIS)

    Ericson, M.; Figureau, A.

    1981-02-01

    The part of the static nuclear axial polarizability arising from the nucleonic excitations is derived from the low energy expansion of the πN amplitude. It is shown that the contribution of the Δ intermediate state, though dominant, does not saturate the nucleonic response. A similar effect, though more pronounced, is known to occur for the magnetic susceptibility

  14. Excitation modes in non-axial nuclei

    International Nuclear Information System (INIS)

    Leviatan, A.; Ginnochio, J.N.

    1990-01-01

    Excitation modes of non-axial quadrupole shapes are investigated in the framework of interacting boson models. Both γ-unstable and γ-rigid nuclear shapes are considered for systems with one type of boson as well as with proton-neutron bosons. 6 refs

  15. Excitation modes in non-axial nuclei

    Energy Technology Data Exchange (ETDEWEB)

    Leviatan, A.; Ginnochio, J.N.

    1990-01-01

    Excitation modes of non-axial quadrupole shapes are investigated in the framework of interacting boson models. Both {gamma}-unstable and {gamma}-rigid nuclear shapes are considered for systems with one type of boson as well as with proton-neutron bosons. 6 refs.

  16. AERODYNAMIC DESIGN OF HIGH PRESSRE AXIAL FAN

    Directory of Open Access Journals (Sweden)

    Y. A. Ryzhov

    2014-01-01

    Full Text Available The paper presents the results of numerical studies of flow in a high axial fan of H-2, the geometric parameters are carefully designed by the author. The coefficients of performance, the total pressure, efficiency and capacity. Shows the benefits of fan of H-2 on several other fans, expressed in increased efficiency with equal dimensions and angles of blade setting.

  17. Co-axial, high energy gamma generator

    Science.gov (United States)

    Reijonen, Jani Petteri [Princeton, NJ; Gicquel, Frederic [Pennington, NJ

    2011-08-16

    A gamma ray generator includes an ion source in a first chamber. A second chamber is configured co-axially around the first chamber at a lower second pressure. Co-axially arranged plasma apertures separate the two chambers and provide for restricted passage of ions and gas from the first to the second chamber. The second chamber is formed by a puller electrode having at least one long channel aperture to draw ions from the first chamber when the puller electrode is subject to an appropriate applied potential. A plurality of electrodes rings in the third chamber in third pressure co-axially surround the puller electrode and have at least one channel corresponding to the at least one puller electrode aperture and plasma aperture. The electrode rings increase the energy of the ions to a selected energy in stages in passing between successive pairs of the electrodes by application of an accelerating voltage to the successive pairs of accelerator electrodes. A target disposed co-axially around the plurality of electrodes receives the beam of accelerated ions, producing gamma rays.

  18. [A biomechanic study on the relapse after sagittal split and oblique osteotomy of Ramus].

    Science.gov (United States)

    Li, Wei; Song, Yufeng; Wang, Dazhang

    2004-02-01

    The relapse after orthognathic surgery was frequently reported in recent years. But up to now researches concerning bio-mechanic mechanism of relapse are rare. The purpose of this study, by imitating the operation on monkeys, was to examine the biomechanical properties and histological characteristics after operation in order to investigate the mechanism of the relapse after orthognathic surgery. 20 rhesus monkeys divided into two groups were subjected to bilateral sagittal split and oblique osteotomy, respectively. The broken strength, stress and strain of the operated sites were examined with the use of biomechanical methods, and the healing scab was observed using histological method and SEM at 3, 6, 12, 24 weeks after operation. The results obtained demonstrated that bone healing and biomechanical properties reached certain level after 6 to 12 weeks' recovery in both operation groups; the biomechanical properties and histological characteristics recovered faster in sagittal split group than in oblique osteotomy group. Histological examination also demonstrated similar results. From the data above it is suggested that the higher relapse rate in sagittal split may more closely related to the mechanical effect different from the scab healing, although 8 weeks' fixation may meet the requirement of clinical treatment, accessory fixation method should be adopted after the removal of inter-maxilla fixation.

  19. The Role of Proprioception in the Sagittal Setting of Anticipatory Postural Adjustments During Gait Initiation

    Directory of Open Access Journals (Sweden)

    Pereira Marcelo P.

    2015-12-01

    Full Text Available Purpose. Previous studies have studied the role of proprioception on the setting of anticipatory postural adjustments (APA during gait initiation. However, these studies did not investigate the role of proprioception in the sagittal APA setting. We aimed to investigate the role of proprioception manipulation to induce APA sagittal adaptations on gait initiation. Methods. Fourteen healthy adults performed gait initiation without, and with, vibration applied before movement onset, and during movement. In addition, the effects of two different vibration frequencies (80 and 120Hz were tested. Vibration was applied bilaterally on the tibialis anterior, rectus femoris and trapezius superior. The first step characteristics, ground reaction forces and CoP behaviour were assessed. Results. Vibration improved gait initiation performance regardless of the moment it was applied. CoP velocity during the initial phase of APA was increased by vibration only when it was applied before movement. When vibration was applied to disturb the movement, no effects on the CoP behaviour were observed. Manipulation of vibration frequency had no effects. Conclusions. Rather than proprioception manipulation, the results suggest that post-vibratory effects and attentional mechanisms were responsible for our results. Taken together, the results show that sagittal APA setting is robust to proprioception manipulation.

  20. CORRELATION BETWEEN OBESITY, SAGITTAL BALANCE AND CLINICAL OUTCOME IN SPINAL FUSION

    Directory of Open Access Journals (Sweden)

    Marcel Machado da Motta

    2015-09-01

    Full Text Available Objective:To correlate obesity with radiographic parameters of spinal and spinopelvic balance in patients undergoing spinal arthrodesis, and to correlate obesity with clinical outcome of these patients.Methods:Observational retrospective study including patients who underwent spinal arthrodesis, with minimum follow-up period of three months. We measured waist circumference, as well as height and weight to calculate body mass index (BMI and obtained radiographs of the total column. The clinical parameters studied were pain by visual analog scale (VAS and the Oswestry questionnaire (ODI. Obesity correlated with radiographic parameters of the sagittal and spinopelvic balance and postoperative clinical parameters.Results:32 patients were analyzed. The higher the BMI, the greater the value of VAS found, but without statistical significance (p=0.83. There was also no correlation between BMI and the ODI questionnaire. Analyzing the abdominal circumference, there was no correlation between the VAS and ODI. There was no correlation between BMI or waist circumference and the radiographic parameters of global spinopelvic sagittal alignment. Regarding the postoperative results, there was no correlation between the mean BMI and waist circumference and the postoperative results for ODI and VAS (p=0.75 and p=0.7, respectively.Conclusions:The clinical outcomes of patients who undergone spinal fusion were not affected by the BMI and waist circumference. Also, there was no correlation between radiographic parameters of spinal and spinopelvic sagittal balance with obesity in patients previously treated with arthrodesis of the spine.

  1. Differences of Sagittal Lumbosacral Parameters between Patients with Lumbar Spondylolysis and Normal Adults.

    Science.gov (United States)

    Yin, Jin; Peng, Bao-Gan; Li, Yong-Chao; Zhang, Nai-Yang; Yang, Liang; Li, Duan-Ming

    2016-05-20

    Recent studies have suggested an association between elevated pelvic incidence (PI) and the development of lumbar spondylolysis. However, there is still lack of investigation for Han Chinese people concerning the normal range of spinopelvic parameters and relationship between abnormal sagittal parameters and lumbar diseases. The objective of the study was to investigate sagittal lumbosacral parameters of adult lumbar spondylolysis patients in Han Chinese population. A total of 52 adult patients with symptomatic lumbar spondylolysis treated in the General Hospital of Armed Police Force (Beijing, China) were identified as the spondylolysis group. All the 52 patients were divided into two subgroups, Subgroup A: 36 patients with simple lumbar spondylolysis, and Subgroup B: 16 patients with lumbar spondylolysis accompanying with mild lumbar spondylolisthesis (slip percentage spondylolysis group and the control group with independent-sample t- test. There were no statistically significant differences of all seven sagittal lumbosacral parameters between Subgroup A and Subgroup B. PI, PT, SS, and LL were higher (P spondylolysis group than those in the control group, but STA was lower (P spondylolysis group. Current study results suggest that increased PI and decreased STA may play important roles in the pathology of lumbar spondylolysis in Han Chinese population.

  2. WAVELET ANALYSIS AND NEURAL NETWORK CLASSIFIERS TO DETECT MID-SAGITTAL SECTIONS FOR NUCHAL TRANSLUCENCY MEASUREMENT

    Directory of Open Access Journals (Sweden)

    Giuseppa Sciortino

    2016-04-01

    Full Text Available We propose a methodology to support the physician in the automatic identification of mid-sagittal sections of the fetus in ultrasound videos acquired during the first trimester of pregnancy. A good mid-sagittal section is a key requirement to make the correct measurement of nuchal translucency which is one of the main marker for screening of chromosomal defects such as trisomy 13, 18 and 21. NT measurement is beyond the scope of this article. The proposed methodology is mainly based on wavelet analysis and neural network classifiers to detect the jawbone and on radial symmetry analysis to detect the choroid plexus. Those steps allow to identify the frames which represent correct mid-sagittal sections to be processed. The performance of the proposed methodology was analyzed on 3000 random frames uniformly extracted from 10 real clinical ultrasound videos. With respect to a ground-truth provided by an expert physician, we obtained a true positive, a true negative and a balanced accuracy equal to 87.26%, 94.98% and 91.12% respectively.

  3. Characteristics of Low-latitude Coronal Holes near the Maximum of Solar Cycle 24

    Energy Technology Data Exchange (ETDEWEB)

    Hofmeister, Stefan J.; Veronig, Astrid; Reiss, Martin A.; Temmer, Manuela [University of Graz, Institute of Physics, IGAM-Kanzelhöhe Observatory, Graz (Austria); Vennerstrom, Susanne [National Space Institute, DTU Space (Denmark); Vršnak, Bojan [Hvar Observatory, Faculty of Geodesy, Zagreb (Croatia); Heber, Bernd, E-mail: stefan.hofmeister@uni-graz.at [Universität Kiel, Institut für Experimentelle und Angewandte Physik, Kiel (Germany)

    2017-02-01

    We investigate the statistics of 288 low-latitude coronal holes extracted from SDO /AIA-193 filtergrams over the time range of 2011 January 01–2013 December 31. We analyze the distribution of characteristic coronal hole properties, such as the areas, mean AIA-193 intensities, and mean magnetic field densities, the local distribution of the SDO /AIA-193 intensity and the magnetic field within the coronal holes, and the distribution of magnetic flux tubes in coronal holes. We find that the mean magnetic field density of all coronal holes under study is 3.0 ± 1.6 G, and the percentaged unbalanced magnetic flux is 49 ± 16%. The mean magnetic field density, the mean unsigned magnetic field density, and the percentaged unbalanced magnetic flux of coronal holes depend strongly pairwise on each other, with correlation coefficients cc > 0.92. Furthermore, we find that the unbalanced magnetic flux of the coronal holes is predominantly concentrated in magnetic flux tubes: 38% (81%) of the unbalanced magnetic flux of coronal holes arises from only 1% (10%) of the coronal hole area, clustered in magnetic flux tubes with field strengths >50 G (10 G). The average magnetic field density and the unbalanced magnetic flux derived from the magnetic flux tubes correlate with the mean magnetic field density and the unbalanced magnetic flux of the overall coronal hole (cc>0.93). These findings give evidence that the overall magnetic characteristics of coronal holes are governed by the characteristics of the magnetic flux tubes.

  4. Analysis of variation of sagittal position of the jaw bones in skeletal class III malocclusion

    Directory of Open Access Journals (Sweden)

    Stojanović Zdenka

    2012-01-01

    Full Text Available Background/Aim. Skeletal Class III malocclusion is a discrepancy in the sagittal jaw relationship, due to imbalances in their development and/or position, resulting in the dominant appearance of the lower jaw in facial profile. The aim of this study was to determine variations in the sagittal position of the jaw bones to the cranial base in subjects with skeletal Class III, for the earliest possible diagnosis of malocclusion. Methods. Fifty children and as many adults with skeletal Class III, both sexes, were examined and selected, based on the findings of sagittal interjaw relationship (ANB ≤ 0° from the cephalometric analysis of tele-x-ray profile head shots. The subjects were grouped according to age. The first group consisted of children aged 6-12 years, and another group, of adults aged 18-26 years. We measured the angles of maxillary prognathism (SNA, mandibular prognathism (SNB and ANB. Based on these results, within the respective groups subclassification into the subgroups was done, among which a significant difference measured values was evaluated. In both groups a significant correlation of the determined values was evaluated. Results. An average SNA angle ranged 77.36 ± 3.58 in children and 77.32 ± 4.88 in adults, while an average SNB angle was 79.46 ± 3.91 in the group of children and 81.12 ± 3.76 in adults. An average ANB angle was -2.10 ± 2.07 in children, and -4.00 ± 2.34 in adults. In both groups, a significant correlation between the measured values and a significant difference in the values of all the measured parameters were found between patients from different subgroups (p < 0.01. Conclusion. The most common morphological variation of sagittal position of the upper jaw is its retrognatism, which is equally present in both children and adults. Sagittal position of the lower jaw in most of the adults was prognathic, while mandible prognathism in the children was less present.

  5. Non-structural misalignments of body posture in the sagittal plane.

    Science.gov (United States)

    Czaprowski, Dariusz; Stoliński, Łukasz; Tyrakowski, Marcin; Kozinoga, Mateusz; Kotwicki, Tomasz

    2018-01-01

    The physiological sagittal spinal curvature represents a typical feature of good body posture in the sagittal plane. The cervical and the lumbar spine are curved anteriorly (lordosis), while the thoracic segment is curved posteriorly (kyphosis). The pelvis is inclined anteriorly, and the lower limbs' joints remain in a neutral position. However, there are many deviations from the optimal body alignment.The aim of this paper is to present the most common types of non-structural misalignments of the body posture in the sagittal plane. The most common types of non-structural misalignments of body posture in the sagittal plane are as follows: (1) lordotic, (2) kyphotic, (3) flat-back, and (4) sway-back postures. Each one may influence both the skeletal and the muscular system leading to the functional disturbance and an increased strain of the supporting structures. Usually, the disturbances localized within the muscles are analyzed in respect to their shortening or lengthening. However, according to suggestions presented in the literature, when the muscles responsible for maintaining good body posture (the so-called stabilizers) are not being stimulated to resist against gravity for an extended period of time, e.g., during prolonged sitting, their stabilizing function is disturbed by the hypoactivity reaction resulting in muscular weakness. The deficit of the locomotor system stability triggers a compensatory mechanism-the stabilizing function is overtaken by the so-called mobilizing muscles. However, as a side effect, such compensation leads to the increased activity of mobilizers (hyperactivity) and decreased flexibility, which may finally lead to the pathological chain of reaction within the musculoskeletal system. There exist four principal types of non-structural body posture misalignments in the sagittal plane: lordotic posture, kyphotic posture, flat-back posture, and sway-back posture. Each of them can disturb the physiological loading of the musculoskeletal

  6. Kelvin-Helmholtz instability in a twisting solar polar coronal hole jet observed by SDO/AIA

    Science.gov (United States)

    Zhelyazkov, I.; Zaqarashvili, T. V.; Ofman, L.; Chandra, R.

    2018-01-01

    We investigate the conditions under which the fluting (m = 2), m = 3 , and m = 12 magnetohydrodynamic (MHD) modes in a uniformly twisted flux tube moving along its axis become unstable in order to model the Kelvin-Helmholtz (KH) instability in a twisting solar coronal hole jet near the northern pole of the Sun. We employed the dispersion relations of MHD modes derived from the linearized MHD equations. We assumed real wavenumbers and complex angular wave frequencies, namely complex wave phse velocities. The dispersion relations were solved numerically at fixed input parameters (taken from observational data) and varying degrees of torsion of the internal magnetic field. It is shown that the stability of the modes depends upon five parameters: the density contrast between the flux tube and its environment, the ratio of the external and internal axial magnetic fields, the twist of the magnetic field lines inside the tube, the ratio of transverse and axial jet's velocities, and the value of the Alfvén Mach number (the ratio of the tube axial velocity to Alfvén speed inside the flux tube). Using a twisting jet of 2010 August 21 by SDO/AIA and other observations of coronal jets we set the parameters of our theoretical model and have obtained that in a twisted magnetic flux tube of radius of 9.8 Mm, at a density contrast of 0.474 and fixed Alfvén Mach number of ≅ 0.76 , for the three MHD modes there exist instability windows whose width crucially depends upon the internal magnetic field twist. It is found that for the considered modes an azimuthal magnetic field of 1.3 - 1.4 G (computed at the tube boundary) makes the width of the instability windows equal to zero, that is, it suppress the KH instability onset. On the other hand, the times for developing KH instability of the m = 12 MHD mode at instability wavelengths between 15 and 12 Mm turn out to be in the range of 1.9 - 4.7 min that is in agreement with the growth rates estimated from the temporal evolution of

  7. Standing sausage modes in coronal loops with plasma flow

    Science.gov (United States)

    Li, Bo; Chen, Shao-Xia; Xia, Li-Dong; Yu, Hui

    2014-08-01

    Context. Magnetohydrodynamic waves are important for diagnosing the physical parameters of coronal plasmas. Field-aligned flows appear frequently in coronal loops. Aims: We examine the effects of transverse density and plasma flow structuring on standing sausage modes trapped in coronal loops, and examine their observational implications in the context of coronal seismology. Methods: We model coronal loops as straight cold cylinders with plasma flow embedded in a static corona. An eigen-value problem governing propagating sausage waves is formulated and its solutions are employed to construct standing modes. Two transverse profiles are distinguished, and are called profiles E and N. A parameter study is performed on the dependence of the maximum period Pmax and cutoff length-to-radius ratio (L/a)cutoff in the trapped regime on the density parameters (ρ0/ρ∞ and profile steepness p) and the flow parameters (its magnitude U0 and profile steepness u). Results: For either profile, introducing a flow reduces Pmax obtainable in the trapped regime relative to the static case. The value of Pmax is sensitive to p for profile N, but is insensitive to p for profile E. By far the most important effect a flow introduces is to reduce the capability for loops to trap standing sausage modes: (L/a)cutoff may be substantially reduced in the case with flow relative to the static one. In addition, (L/a)cutoff is smaller for a stronger flow, and for a steeper flow profile when the flow magnitude is fixed. Conclusions: If the density distribution can be described by profile N, then measuring the sausage mode period can help deduce the density profile steepness. However, this practice is not feasible if profile E more accurately describes the density distribution. Furthermore, even field-aligned flows with magnitudes substantially smaller than the ambient Alfvén speed can make coronal loops considerably less likely to support trapped standing sausage modes. Appendix A is available in

  8. Magnetic resonance diagnosis of posterior horn tears of the lateral meniscus using a thin axial plane: the zip sign - a preliminary study

    International Nuclear Information System (INIS)

    Savoye, P.Y.; Ravey, J.N.; Dubois, C.; Barbier, L.P.; Ferretti, G.; Courvoisier, A.; Saragaglia, D.

    2011-01-01

    The ''zip'' sign is a newly described form of meniscal tear progressing from the distal insertion of menisco-femoral ligaments (MFLs) through the lateral meniscal wall; the tear occurs during anterior cruciate ligament (ACL) rupture. The purpose of this study was to evaluate the zip sign on knee MRI within the context of ACL injuries. From a series of 261 MR examinations for acute knee injury, we selected 97 patients with both MR and arthroscopic data for a retrospective blinded review. The zip sign was defined on axial thin MR sections as a straight line from the distal insertion of MFLs in association with five sagittal images lateral to the posterior cruciate ligament (PCL) where the MFLs were identified. Sensitivity and specificity in detecting lateral meniscal tears before and after having defined the zip sign were calculated. Sensitivity in detecting the tears of the posterior horn of the lateral meniscus (PHLM) reached 87.5% (CI 0.68-0.97) after zip sign criteria were defined. The zip sign has excellent inter-observer agreement, K > 0.90. The zip sign indicates a lesion at the insertion site of MFLs into the PHLM on thin axial images associated with sagittal MR sections that may improve MR sensitivity in detecting PHLM tears. (orig.)

  9. Magnetic resonance diagnosis of posterior horn tears of the lateral meniscus using a thin axial plane: the zip sign - a preliminary study

    Energy Technology Data Exchange (ETDEWEB)

    Savoye, P.Y.; Ravey, J.N.; Dubois, C.; Barbier, L.P.; Ferretti, G. [CHU Grenoble, Clinique Universitaire de Radiologie et d' Imagerie Medicale, B.P 217, Grenoble Cedex 09 (France); Courvoisier, A.; Saragaglia, D. [CHU Grenoble, Clinique Universitaire de Chirurgie Orthopedique et Traumatologique, Grenoble (France)

    2011-01-15

    The ''zip'' sign is a newly described form of meniscal tear progressing from the distal insertion of menisco-femoral ligaments (MFLs) through the lateral meniscal wall; the tear occurs during anterior cruciate ligament (ACL) rupture. The purpose of this study was to evaluate the zip sign on knee MRI within the context of ACL injuries. From a series of 261 MR examinations for acute knee injury, we selected 97 patients with both MR and arthroscopic data for a retrospective blinded review. The zip sign was defined on axial thin MR sections as a straight line from the distal insertion of MFLs in association with five sagittal images lateral to the posterior cruciate ligament (PCL) where the MFLs were identified. Sensitivity and specificity in detecting lateral meniscal tears before and after having defined the zip sign were calculated. Sensitivity in detecting the tears of the posterior horn of the lateral meniscus (PHLM) reached 87.5% (CI 0.68-0.97) after zip sign criteria were defined. The zip sign has excellent inter-observer agreement, K > 0.90. The zip sign indicates a lesion at the insertion site of MFLs into the PHLM on thin axial images associated with sagittal MR sections that may improve MR sensitivity in detecting PHLM tears. (orig.)

  10. Problems arising in differential diagnosis in the chest X-ray in patients with small sagittal diameter of the thorax

    International Nuclear Information System (INIS)

    Huebsch, P.; Stiglbauer, R.; Barton, P.; Frank, H.

    1989-01-01

    In patients with a small sagittal diameter of the thorax often carcia murmurs are heard. Since the p.a. chest X-ray in such cases often shows an enlarged heart shadow, problems arise in the interpretation of the films. In this paper, the typical appearance of the heart shadow in patients with small sagittal diameter of the thorax is described and the differential diagnosis is discussed. Echocardiography is the ideal additional diagnostic method, when problems in differential diagnosis occur. (orig.) [de

  11. High-resolution computed tomography of the osseous temporomandibular joint

    International Nuclear Information System (INIS)

    Larheim, T.A.; Kolbenstvedt, A.; Rikshospitalet, Oslo

    1984-01-01

    A standardized CT procedure for examination of the temporomandibular joint (TMJ) with axial and coronal scanning as well as reformatted coronal and sagittal sections, was performed on 32 adults. These included subjects with normal TMJ and patients suffering from muscular dysfunction/disc displacement, arthrosis or rheumatoid arthritis. Some normal CT appearances simulating disease were presented. Axial CT scanning appeared to be the most useful method for demonstrating osseous abnormalities of the TMJ. The diagnostic information was occasionally supplemented by the coronal scanning, which may be difficult to perform on patients with neck stiffness. Reformatted coronal or sagittal sections mostly confirmed TMJ abnormality and supplemented the findings at axial scans in about one third of the patients. (orig.)

  12. MRI of the shoulder joint with surface coils at 1. 5 Tesla. Normal anatomy and possible clinical application

    Energy Technology Data Exchange (ETDEWEB)

    Beyer, D.; Steinbrich, W.; Krestin, G.; Koebke, J.; Kummer, B.; Bunke, J.

    1987-03-01

    High spatial resolution magnetic resonance images of the shoulder were obtained in axial, sagittal and coronal orientations using a 1.5 T imaging system and anatomically shaped, wrap-around surface coils. Variations in scapular position induced by patient positioning change the relationship of the planes to the shoulder anatomy and make reproducibility of sagittal and coronal planes difficult. We, therefore, use - after axial orientation - image-oblique planes perpendicular and parallel to the glenoid fossa. In this manner MRI can visualise the anatomic structures of the shoulder including rotator cuff, long biceps tendon, articular capsule, articular cartilage, muscles and bones due to the high soft tissue contrast of MRI.

  13. Shear-induced inflation of coronal magnetic fields

    International Nuclear Information System (INIS)

    Klimchuk, J.A.

    1990-01-01

    Using numerical models of force-free magnetic fields, the shearing of footprints in arcade geometries leading to an inflation of the coronal magnetic field was examined. For each of the shear profiles considered, all of the field lines become elevated compared with the potential field. This includes cases where the shear is concentrated well away from the arcade axis, such that B(sub z), the component of field parallel to the axis, increases outward to produce an inward B(sub z) squared/8 pi magnetic pressure gradient force. These results contrast with an earlier claim, shown to be incorrect, that field lines can sometimes become depressed as a result of shear. It is conjectured that an inflation of the entire field will always result from the shearing of simple arcade configurations. These results have implications for prominence formation, the interplanetary magnetic flux, and possibly also coronal holes. 38 refs

  14. Review of Axial Burnup Distribution Considerations for Burnup Credit Calculations

    Energy Technology Data Exchange (ETDEWEB)

    Wagner, J.C.; DeHart, M.D.

    2000-03-01

    This report attempts to summarize and consolidate the existing knowledge on axial burnup distribution issues that are important to burnup credit criticality safety calculations. Recently released Nuclear Regulatory Commission (NRC) staff guidance permits limited burnup credit, and thus, has prompted resolution of the axial burnup distribution issue. The reactivity difference between the neutron multiplication factor (keff) calculated with explicit representation of the axial burnup distribution and keff calculated assuming a uniform axial burnup is referred to as the ``end effect.'' This end effect is shown to be dependent on many factors, including the axial-burnup profile, total accumulated burnup, cooling time, initial enrichment, assembly design, and the isotopics considered (i.e., actinide-only or actinides plus fission products). Axial modeling studies, efforts related to the development of axial-profile databases, and the determination of bounding axial profiles are also discussed. Finally, areas that could benefit from further efforts are identified.

  15. Review of Axial Burnup Distribution Considerations for Burnup Credit Calculations

    International Nuclear Information System (INIS)

    Wagner, J.C.; DeHart, M.D.

    2000-01-01

    This report attempts to summarize and consolidate the existing knowledge on axial burnup distribution issues that are important to burnup credit criticality safety calculations. Recently released Nuclear Regulatory Commission (NRC) staff guidance permits limited burnup credit, and thus, has prompted resolution of the axial burnup distribution issue. The reactivity difference between the neutron multiplication factor (keff) calculated with explicit representation of the axial burnup distribution and keff calculated assuming a uniform axial burnup is referred to as the ''end effect.'' This end effect is shown to be dependent on many factors, including the axial-burnup profile, total accumulated burnup, cooling time, initial enrichment, assembly design, and the isotopics considered (i.e., actinide-only or actinides plus fission products). Axial modeling studies, efforts related to the development of axial-profile databases, and the determination of bounding axial profiles are also discussed. Finally, areas that could benefit from further efforts are identified

  16. Piping inspection carriage having axially displaceable sensor

    Science.gov (United States)

    Zollinger, W.T.; Treanor, R.C.

    1994-12-06

    A pipe inspection instrument carriage is described for use with a pipe crawler for performing internal inspections of piping surfaces. The carriage has a front leg assembly, a rear leg assembly and a central support connecting the two assemblies and for mounting an instrument arm having inspection instruments. The instrument arm has a Y-arm mounted distally thereon for axially aligning the inspection instrumentation and a mounting block, a linear actuator and axial movement arm for extending the inspection instruments radially outward to operably position the inspection instruments on the piping interior. Also, the carriage has a rotation motor and gear assembly for rotating the central support and the front leg assembly with respect to the rear leg assembly so that the inspection instruments azimuthally scan the piping interior. The instrument carriage allows performance of all piping inspection operations with a minimum of moving parts, thus decreasing the likelihood of performance failure. 4 figures.

  17. Ventajas de los motores de flujo axial

    Directory of Open Access Journals (Sweden)

    Alberto M Basanta Otero

    2011-03-01

    Full Text Available Es importante conocer sobre una familia de motores que a diferencia de los convencionales o tradicionales no presentanun flujo rotatorio radial, denominados motores de flujo axial. Dichos motores presentan altos valores de par motriz abajas velocidades, una alta eficiencia y alta densidad de potencia. Este trabajo constituye un breve análisis dealgunos motores de la referencia bibliográfica.  Is important to know about a family of motors that at difference whit the traditional, don't have a rotator radial flux,called, axial flux motors. These motors have high torque for low speed, high efficiency and high power density. Thiswork is a brief analysis of several motors of the bibliographic references.

  18. Cross-flow filtration and axial filtration

    International Nuclear Information System (INIS)

    Kraus, K.A.

    1974-01-01

    Two relatively novel alternative solid-liquid-separation techniques of filtration are discussed. In cross-flow filtration, the feed is pumped past the filtering surface. While in axial filtration the filter, mounted on a rotor, is moved with respect to the feed. While large-scale application of the axial filter is still in doubt, it permits with little expenditure of time and money, duplication of many hydrodynamic aspects of cross-flow filtration for fine-particle handling problems. The technique has been applied to municipal wastes, low-level radioactive waste treatment plant, lead removal from industrial wastes, removal of pulp-mill contaminants, textile-mill wastes, and pretreatment of saline waters by lime-soda process in preparation for hyperfiltration. Economics and energy requirements are also discussed

  19. Morphology and physical properties of solar coronal holes

    International Nuclear Information System (INIS)

    Rozelot, J.P.

    1983-01-01

    By their peculiar characteristics, coronal holes induce on Earth climatic variations and cyclic effects, not well known nowadays. Because of low electronical density and very low temperature, study of these holes was neglected. The author presents the results of the observations from discovery in the fifteens. He gives some new results, a theoretical model and not well resolved questions which can conduct to new methods of searching [fr

  20. Polarisation of microwave emission from reconnecting twisted coronal loops

    Science.gov (United States)

    Gordovskyy, M.; Browning, P. K.; Kontar, E. P.

    2017-08-01

    Context. Magnetic reconnection and particle acceleration due to the kink instability in twisted coronal loops can be a viable scenario for confined solar flares. Detailed investigation of this phenomenon requires reliable methods for observational detection of magnetic twist in solar flares, which may not be possible solely through extreme UV and soft X-ray thermal emission. Polarisation of microwave emission in flaring loops can be used as one of the detection criteria. Aims: The aim of this study is to investigate the effect of magnetic twist in flaring coronal loops on the polarisation of gyro-synchrotron microwave (GSMW) emission, and determine whether it could provide a means for magnetic twist detection. Methods: We consider time-dependent magnetohydrodynamic and test-particle models developed using the LARE3D and GCA codes to investigate twisted coronal loops that relax after kink instability. Synthetic GSMW emission maps (I and V Stokes components) are calculated using GX simulator. Results: It is found that flaring twisted coronal loops produce GSMW radiation with a gradient of circular polarisation across the loop. However, these patterns may be visible only for a relatively short period of time owing to fast magnetic reconfiguration after the instability. Their visibility also depends on the orientation and position of the loop on the solar disk. Typically, it would be difficult to see these characteristic polarisation patterns in a twisted loop seen from the top (I.e. close to the centre of the solar disk), but easier in a twisted loop seen from the side (I.e. observed very close to the limb).

  1. Swift X-ray monitoring of stellar coronal variability

    Science.gov (United States)

    Miller, Brendan; Hagen, Cedric; Gallo, Elena; Wright, Jason T.

    2018-01-01

    We used California Planet Search Ca II H and K core emission measurements to identify and characterize chromospheric activity cycles in a sample of main-sequence FGK stars. About a dozen of these with existing ROSAT archival data were targeted with Swift to obtain a current epoch X-ray flux. We find that coronal variability by a factor of several is common on decade-long timescales (we attempt to link to the chromospheric cycle phase) but can also occur on short timescales between Swift visits to a given target, presumably related to stellar rotation and coronal inhomogeneity or to small flares. Additionally, we present new Swift monitoring observations of two M dwarfs with known exoplanets: GJ 15A and GJ 674. GJ 15A b is around 5.3 Earth masses with an 11.4 day orbital period, while GJ 674 is around 11.1 Earth masses with a 4.7 day orbital period. GJ 15A was observed several times in late 2014 and then monitored at approximately weekly intervals for several months in early 2016, for a total exposure of 18 ks. GJ 674 was monitored at approximately weekly intervals for most of 2016, for a total exposure of 40 ks. We provide light curves and hardness ratios for both sources, and also compare to earlier archival X-ray data. Both sources show significant X-ray variability, including between consecutive observations. We quantify the energy distribution for coronal flaring, and compare to optical results for M dwarfs from Kepler. Finally, we discuss the implications of M dwarf coronal activity for exoplanets orbiting within the nominal habitable zone.

  2. Axial pattern skin flaps in cats.

    Science.gov (United States)

    Remedios, A M; Bauer, M S; Bowen, C V; Fowler, J D

    1991-01-01

    The major direct cutaneous vessels identified in the cat include the omocervical, thoracodorsal, deep circumflex iliac, and caudal superficial epigastric arteries. Axial pattern skin flaps based on the thoracodorsal and caudal superficial epigastric arteries have been developed in cats. Rotation of these flaps as islands allows skin coverage to the carpus and metatarsus, respectively. The thoracodorsal and caudal superficial epigastric flaps provide a practical, one-step option in the reconstruction of large skin defects involving the distal extremities of cats.

  3. Atlanto-axial subluxation: a case report

    OpenAIRE

    Thurlow, Robert D

    1988-01-01

    One of the causes of death in rheumatoid patients is cord compression following atlanto-axial subluxation. Dislocations in the cervical spine are common with patients who have rheumatoid arthritis. Anterior subluxation occurs in up to 35%, followed by vertical subluxation in 22.2%, lateral subluxation in 20.6% and rarely posterior subluxation. A case report is presented to illustrate such a complication.

  4. Axial flux permanent magnet brushless machines

    CERN Document Server

    Gieras, Jacek F; Kamper, Maarten J

    2008-01-01

    Axial Flux Permanent Magnet (AFPM) brushless machines are modern electrical machines with a lot of advantages over their conventional counterparts. They are being increasingly used in consumer electronics, public life, instrumentation and automation system, clinical engineering, industrial electromechanical drives, automobile manufacturing industry, electric and hybrid electric vehicles, marine vessels and toys. They are also used in more electric aircrafts and many other applications on larger scale. New applications have also emerged in distributed generation systems (wind turbine generators

  5. Cervical Spine Axial Rotation Goniometer Design

    OpenAIRE

    Emin Ulaş Erdem; Filiz Can

    2012-01-01

    To evaluate the cervical spine rotation movement is quiet harder than other joints. Configuration and arrangement of current goniometers and devices is not always practic in clinics and some methods are quiet expensive. The cervical axial rotation goniometer designed by the authors is consists of five pieces (head apparatus, chair, goniometric platform, eye pads and camera). With this goniometer design a detailed evaluation of cervical spine range of motion can be obtained. Besides, measureme...

  6. A RECONNECTION-DRIVEN RAREFACTION WAVE MODEL FOR CORONAL OUTFLOWS

    International Nuclear Information System (INIS)

    Bradshaw, S. J.; Aulanier, G.; Del Zanna, G.

    2011-01-01

    We conduct numerical experiments to determine whether interchange reconnection at high altitude coronal null points can explain the outflows observed as blueshifts in coronal emission lines at the boundaries between open and closed magnetic field regions. In this scenario, a strong, post-reconnection pressure gradient forms in the field-aligned direction when dense and hot, active region core loops reconnect with neighboring tenuous and cool, open field lines. We find that the pressure gradient drives a supersonic outflow and a rarefaction wave develops in both the open and closed post-reconnection magnetic field regions. We forward-model the spectral line profiles for a selection of coronal emission lines to predict the spectral signatures of the rarefaction wave. We find that the properties of the rarefaction wave are consistent with the observed velocity versus temperature structure of the corona in the outflow regions, where the velocity increases with the formation temperature of the emission lines. In particular, we find excellent agreement between the predicted and observed Fe XII 195.119 Å spectral line profiles in terms of the blueshift (10 km s –1 ), full width at half-maximum (83 mÅ) and symmetry. Finally, we find that T i e in the open field region, which indicates that the interchange reconnection scenario may provide a viable mechanism and source region for the slow solar wind.

  7. Coronal Holes and Magnetic Flux Ropes Interweaving Solar Cycles

    Science.gov (United States)

    Lowder, Chris; Yeates, Anthony; Leamon, Robert; Qiu, Jiong

    2016-10-01

    Coronal holes, dark patches observed in solar observations in extreme ultraviolet and x-ray wavelengths, provide an excellent proxy for regions of open magnetic field rooted near the photosphere. Through a multi-instrument approach, including SDO data, we are able to stitch together high resolution maps of coronal hole boundaries spanning the past two solar activity cycles. These observational results are used in conjunction with models of open magnetic field to probe physical solar parameters. Magnetic flux ropes are commonly defined as bundles of solar magnetic field lines, twisting around a common axis. Photospheric surface flows and magnetic reconnection work in conjunction to form these ropes, storing magnetic stresses until eruption. With an automated methodology to identify flux ropes within observationally driven magnetofrictional simulations, we can study their properties in detail. Of particular interest is a solar-cycle length statistical description of eruption rates, spatial distribution, magnetic orientation, flux, and helicity. Coronal hole observations can provide useful data about the distribution of the fast solar wind, with magnetic flux ropes yielding clues as to ejected magnetic field and the resulting space weather geo-effectiveness. With both of these cycle-spanning datasets, we can begin to form a more detailed picture of the evolution and consequences of both sets of solar magnetic features.

  8. Spatial damping of propagating sausage waves in coronal cylinders

    Science.gov (United States)

    Guo, Ming-Zhe; Chen, Shao-Xia; Li, Bo; Xia, Li-Dong; Yu, Hui

    2015-09-01

    Context. Sausage modes are important in coronal seismology. Spatially damped propagating sausage waves were recently observed in the solar atmosphere. Aims: We examine how wave leakage influences the spatial damping of sausage waves propagating along coronal structures modeled by a cylindrical density enhancement embedded in a uniform magnetic field. Methods: Working in the framework of cold magnetohydrodynamics, we solve the dispersion relation (DR) governing sausage waves for complex-valued, longitudinal wavenumber k at given real angular frequencies ω. For validation purposes, we also provide analytical approximations to the DR in the low-frequency limit and in the vicinity of ωc, the critical angular frequency separating trapped from leaky waves. Results: In contrast to the standing case, propagating sausage waves are allowed for ω much lower than ωc. However, while able to direct their energy upward, these low-frequency waves are subject to substantial spatial attenuation. The spatial damping length shows little dependence on the density contrast between the cylinder and its surroundings, and depends only weakly on frequency. This spatial damping length is of the order of the cylinder radius for ω ≲ 1.5vAi/a, where a and vAi are the cylinder radius and the Alfvén speed in the cylinder, respectively. Conclusions: If a coronal cylinder is perturbed by symmetric boundary drivers (e.g., granular motions) with a broadband spectrum, wave leakage efficiently filters out the low-frequency components.

  9. Fast-sausage oscillations in coronal loops with smooth boundary

    Science.gov (United States)

    Lopin, I.; Nagorny, I.

    2014-12-01

    Aims: The effect of the transition layer (shell) in nonuniform coronal loops with a continuous radial density profile on the properties of fast-sausage modes are studied analytically and numerically. Methods: We modeled the coronal waveguide as a structured tube consisting of a cord and a transition region (shell) embedded within a magnetic uniform environment. The derived general dispersion relation was investigated analytically and numerically in the context of frequency, cut-off wave number, and the damping rate of fast-sausage oscillations for various values of loop parameters. Results: The frequency of the global fast-sausage mode in the loops with a diffuse (or smooth) boundary is determined mainly by the external Alfvén speed and longitudinal wave number. The damping rate of such a mode can be relatively low. The model of coronal loop with diffuse boundary can support a comparatively low-frequency, global fast-sausage mode of detectable quality without involving extremely low values of the density contrast. The effect of thin transition layer (corresponds to the loops with steep boundary) is negligible and produces small reductions of oscillation frequency and relative damping rate in comparison with the case of step-function density profile. Seismological application of obtained results gives the estimated Alfvén speed outside the flaring loop about 3.25 Mm/s.

  10. Restorative treatment for initial, cavitated and gross coronal carious lesions.

    Science.gov (United States)

    Brennan, D S; Balasubramanian, M; Spencer, A J

    2016-09-01

    Treatment patterns for caries have been shown to reflect high rates of restorative services. The objective of this study was to investigate types of restorative treatment provided to patients with a main diagnosis of coronal caries in relation to the severity of the caries lesion. A random sample of Australian dentists was surveyed by mailed questionnaires in 2009-2010 (response rate 67%). Data on types of restorative treatment, patient characteristics and main diagnosis were collected from a service log. Models of service rates adjusted for age, gender, insurance status and reason for visit showed that compared to the reference category of initial caries lesions, there were lower rates [Rate Ratio, 95% CI] of adhesive anterior restorative services [0.57, 0.34-0.95] and lower rates of adhesive posterior restorations [0.56, 0.40-0.79] for gross lesions. Treatment of coronal caries was characterized by high rates of adhesive posterior restorative services, but gross lesions had lower rates of both anterior and posterior adhesive restorations. Types of restorative treatment for coronal caries were similar between initial and cavitated lesions. This could indicate scope for the adoption of more minimum intervention approaches to the management of initial carious lesions. © 2015 Australian Dental Association.

  11. Do coronal holes influence cosmic ray daily harmonics

    International Nuclear Information System (INIS)

    Ahluwalia, H.S.

    1977-01-01

    Coronal holes are identified by their low emissivity in either EUV (Munro and Withrobe, 1973) or in X-rays (Krieger et al, 1973). They are seats of unidirectional magnetic fields. Also, high speed solar wind streams originate in them. Also, high speed solar wind streams originate in then (Krieger et al, 1973; Neupert and Pizzo, 1974; Nolte et al, 1976). Coronal holes often extend over a wide range of heliolatitudes (Timothy et al, 1975). Elsewhere in the Proceedings we have presented results on the long term changes observed in the amplitudes and the times of maximum of the diurnal, the semidiurnal and the tridiurnal variations of cosmic rays, at low (neutrons) and at high (underground muons) primary rigidities (Ahluwalia, 1977). We have shown that a dramatic shift to early hours is noticeable in the times of maxima of the harmonics during 1971-72 period. In this paper we examine the nature of the contributions of off-ecliptic cosmic rays of high enough rigidity, streaming under the influence of large scale ordered interplanetary magnetic field set up by the coronal holes, to the cosmic ray daily harmonics. Some models are presented and discussed in a preliminary fashion. (author)

  12. Axial gravity, massless fermions and trace anomalies

    Energy Technology Data Exchange (ETDEWEB)

    Bonora, L. [International School for Advanced Studies (SISSA), Trieste (Italy); KEK, Tsukuba (Japan). KEK Theory Center; INFN, Sezione di Trieste (Italy); Cvitan, M.; Giaccari, S.; Stemberga, T. [Zagreb Univ. (Croatia). Dept. of Physics; Prester, P.D. [Rijeka Univ. (Croatia). Dept. of Physics; Pereira, A.D. [UERJ-Univ. Estadual do Rio de Janeiro (Brazil). Dept. de Fisica Teorica; UFF-Univ. Federal Fluminense, Niteroi (Brazil). Inst. de Fisica

    2017-08-15

    This article deals with two main topics. One is odd parity trace anomalies in Weyl fermion theories in a 4d curved background, the second is the introduction of axial gravity. The motivation for reconsidering the former is to clarify the theoretical background underlying the approach and complete the calculation of the anomaly. The reference is in particular to the difference between Weyl and massless Majorana fermions and to the possible contributions from tadpole and seagull terms in the Feynman diagram approach. A first, basic, result of this paper is that a more thorough treatment, taking account of such additional terms and using dimensional regularization, confirms the earlier result. The introduction of an axial symmetric tensor besides the usual gravitational metric is instrumental to a different derivation of the same result using Dirac fermions, which are coupled not only to the usual metric but also to the additional axial tensor. The action of Majorana and Weyl fermions can be obtained in two different limits of such a general configuration. The results obtained in this way confirm the previously obtained ones. (orig.)

  13. Axial polarizability and weak currents in nuclei

    International Nuclear Information System (INIS)

    Ericson, M.

    1977-01-01

    The weak interaction nucleonic coupling constants in nuclei are modified by the presence of the neighbouring nucleons. One type of modification is due to the virtual excitation of the isobars through meson exchange. The influence of the isobars is described by means of the nuclear axial polarizability coefficient. This polarizability is known; it is linked to the p-wave πN scattering volume. A relation is derived between the axial nuclear current and the pion field which incorporates the polarizability effects. This relation has an electromagnetic analogue. It is then possible to derive the axial and pseudoscalar coupling constants from a knowledge of the pion field. This field in turn obeys a Klein-Gordon equation which has to include the isobaric excitations. The propagation of the pion field is similar to that of an electromagnetic wave in a dielectric medium. The strong interaction coupling constant is shown to be renormalized in nuclei by the effect of the various types of correlations. (author)

  14. Dynamic control of knee axial deformities

    Directory of Open Access Journals (Sweden)

    E. E. Malyshev

    2013-01-01

    Full Text Available The authors have evaluated the clinical examination of the patients with axial malalignments in the knee by the original method and device which was named varovalgometer. The measurements were conducted by tension of the cord through the spina iliaca anterior superior and the middle of the lower pole of patella. The deviation of the center of the ankle estimated by metal ruler which was positioned perpendicular to the lower leg axis on the level of the ankle joint line. The results of comparison of our method and computer navigation in 53 patients during the TKA show no statistically significant varieties but they differ by average 5° of valgus in clinical examination in comparison with mechanical axis which was identified by computer navigation. The dynamic control of axial malalignment can be used in clinical practice for estimation of the results of treatment of pathology with axial deformities in the knee; for the control of reduction and secondary displacement of the fractures around the knee; for assessment of instability; in planning of correctional osteotomies and intraoperative control of deformity correction; for estimation of Q angle in subluxation and recurrent dislocation of patella; in planning of TKA; during the growth of child it allows to assess the progression of deformity.

  15. Respiratory effects of transient axial acceleration.

    Science.gov (United States)

    Loring, S H; Lee, H T; Butler, J P

    2001-06-01

    Whereas gravity has an inspiratory effect in upright subjects, transient upward acceleration is reported to have an expiratory effect. To explore the respiratory effects of transient axial accelerations, we measured axial acceleration at the head and transrespiratory pressure or airflow in five subjects as they were dropped or lifted on a platform. For the first 100 ms, upward acceleration caused a decrease in mouth pressure and inspiratory flow, and downward acceleration caused the opposite. We also simulated these experimental observations by using a computational model of a passive respiratory system based on anatomical data and normal respiratory characteristics. After 100 ms, respiratory airflow in our subjects became highly variable, no longer varying with acceleration. Electromyograms of thoracic and abdominal respiratory muscles showed bursts of activity beginning 40-125 ms after acceleration, suggesting reflex responses responsible for subsequent flow variability. We conclude that, in relaxed subjects, transient upward axial acceleration causes inspiratory airflow and downward acceleration causes expiratory airflow, but that after ~100 ms, reflex activation of respiratory musculature largely determines airflow.

  16. Atlanto-Axial Subluxation After Adenoidectomy.

    Science.gov (United States)

    Gross, Isabel Theresia; Bahar-Posey, Laleh

    2017-06-01

    Atlanto-axial subluxation is a rare but potentially serious complication after otolaryngological procedures. We are describing a case of a 4-year-old child who developed atlanto-axial subluxation of the cervical spine after adenoidectomy. Our patient underwent adenoidectomy and, 18 days later, presented to the emergency department with her neck tilted to the left in a cock-robin position and complaining of neck pain persisting since the surgery. A multiplanar 3-dimensional computed tomography was obtained and confirmed the diagnosis of an atlanto-axial subluxation (Fielding type 3). She was managed conservatively with the application of a cervical collar, anti-inflammatory medication, and manual reduction under anesthesia later in the course because of persistence of her symptoms. It is important to consider this diagnosis in any child who undergoes ENT surgical procedures complaining of neck pain subsequent to surgery or holding the head in a fixed position persistently after surgery. Early diagnosis is important to reduce the time between the onset of symptoms and reduction to reduce the risk or need for surgical intervention.

  17. An Estimate of Solar Wind Velocity Profiles in a Coronal Hole and a Coronal Streamer Area (6-40 R(radius symbol)

    Science.gov (United States)

    Patzold, M.; Tsurutani, B. T.; Bird, M. K.

    1995-01-01

    Total electron content data obtained from the Ulysses Solar Corona Experiment (SCE) in 1991 were used to select two data sets, one associated with a coronal hole and the other with coronal streamer crossings. (This is largely equatorial data shortly after solar maximum.) The solar wind velocity profile is estimated for these areas.

  18. The deep structure of Axial Volcano

    Science.gov (United States)

    West, Michael Edwin

    The subsurface structure of Axial Volcano, near the intersection of the Juan de Fuca Ridge and the Cobb-Eickelberg seamount chain in the northeast Pacific, is imaged from an active source seismic experiment. At a depth of 2.25 to 3.5 km beneath Axial lies an 8 km x 12 km region of very low seismic velocities that can only be explained by the presence of magma. In the center of this magma storage chamber at 2--3.5 km below sea floor, the crust is at least 10--20% melt. At depths of 4--5 km there is evidence of additional low concentrations of magma (a few percent) over a larger area. In total, 5--11 km3 of magma are stored in the mid-crust beneath Axial. This is more melt than has been positively identified under any basaltic volcano on Earth. It is also far more than the 0.1--0.2 km3 emplaced during the 1998 eruption. The implied residence time in the magma reservoir of a few hundred to a few thousand years agrees with geochemical trends which suggest prolonged storage and mixing of magmas. The large volume of melt bolsters previous observations that Axial provides much of the material to create crust along its 50 km rift zones. A high velocity ring-shaped feature sits above the magma chamber just outside the caldera walls. This feature is believed to be the result of repeated dike injections from the magma body to the surface during the construction of the volcanic edifice. A rapid change in crustal thickness from 8 to 11 km within 15 km of the caldera implies focused delivery of melt from the mantle. The high flux of magma suggests that melting occurs deeper in the mantle than along the nearby ridge. Melt supply to the volcano is not connected to any plumbing system associated with the adjacent segments of the Juan de Fuca Ridge. This suggests that, despite Axial's proximity to the ridge, the Cobb hot spot currently drives the supply of melt to the volcano.

  19. FIELD TOPOLOGY ANALYSIS OF A LONG-LASTING CORONAL SIGMOID

    International Nuclear Information System (INIS)

    Savcheva, A. S.; Van Ballegooijen, A. A.; DeLuca, E. E.

    2012-01-01

    We present the first field topology analysis based on nonlinear force-free field (NLFFF) models of a long-lasting coronal sigmoid observed in 2007 February with the X-Ray Telescope on Hinode. The NLFFF models are built with the flux rope insertion method and give the three-dimensional coronal magnetic field as constrained by observed coronal loop structures and photospheric magnetograms. Based on these models, we have computed horizontal maps of the current and the squashing factor Q for 25 different heights in the corona for all six days of the evolution of the region. We use the squashing factor to quantify the degree of change of the field line linkage and to identify prominent quasi-separatrix layers (QSLs). We discuss the major properties of these QSL maps and devise a way to pick out important QSLs since our calculation cannot reach high values of Q. The complexity in the QSL maps reflects the high degree of fragmentation of the photospheric field. We find main QSLs and current concentrations that outline the flux rope cavity and that become characteristically S-shaped during the evolution of the sigmoid. We note that, although intermittent bald patches exist along the length of the sigmoid during its whole evolution, the flux rope remains stable for several days. However, shortly after the topology of the field exhibits hyperbolic flux tubes (HFT) on February 7 and February 12 the sigmoid loses equilibrium and produces two B-class flares and associated coronal mass ejections (CMEs). The location of the most elevated part of the HFT in our model coincides with the inferred locations of the two flares. Therefore, we suggest that the presence of an HFT in a coronal magnetic configuration may be an indication that the system is ready to erupt. We offer a scenario in which magnetic reconnection at the HFT drives the system toward the marginally stable state. Once this state is reached, loss of equilibrium occurs via the torus instability, producing a CME.

  20. Diagnostics of Coronal Heating in Solar Active Regions

    Science.gov (United States)

    Fludra, Andrzej; Hornsey, Christopher; Nakariakov, Valery

    2015-04-01

    We aim to develop a diagnostic method for the coronal heating mechanism in active region loops. Observational constraints on coronal heating models have been sought using measurements in the X-ray and EUV wavelengths. Statistical analysis, using EUV emission from many active regions, was done by Fludra and Ireland (2008) who studied power-law relationships between active region integrated magnetic flux and emission line intensities. A subsequent study by Fludra and Warren (2010) for the first time compared fully resolved images in an EUV spectral line of OV 63.0 nm with the photospheric magnetic field, leading to the identification of a dominant, ubiquitous variable component of the transition region EUV emission and a discovery of a steady basal heating, and deriving the dependence of the basal heating rate on the photospheric magnetic flux density. In this study, we compare models of single coronal loops with EUV observations. We assess to what degree observations of individual coronal loops made in the EUV range are capable of providing constraints on the heating mechanism. We model the coronal magnetic field in an active region using an NLFF extrapolation code applied to a photospheric vector magnetogram from SDO/HMI and select several loops that match an SDO/AIA 171 image of the same active region. We then model the plasma in these loops using a 1D hydrostatic code capable of applying an arbitrary heating rate as a function of magnetic field strength along the loop. From the plasma parameters derived from this model, we calculate the EUV emission along the loop in AIA 171 and 335 bands, and in pure spectral lines of Fe IX 17.1 nm and Fe XVI 33.5 nm. We use different spatial distributions of the heating function: concentrated near the loop top, uniform and concentrated near the footpoints, and investigate their effect on the modelled EUV intensities. We find a diagnostics based on the dependence of the total loop intensity on the shape of the heating function

  1. Biomechanical Comparison of Single- and Double-Leg Jump Landings in the Sagittal and Frontal Plane.

    Science.gov (United States)

    Taylor, Jeffrey B; Ford, Kevin R; Nguyen, Anh-Dung; Shultz, Sandra J

    2016-06-01

    Double-leg forward or drop-jump landing activities are typically used to screen for high-risk movement strategies and to determine the success of neuromuscular injury prevention programs. However, research suggests that these tasks that occur primarily in the sagittal plane may not adequately represent the lower extremity biomechanics that occur during unilateral foot contact or non-sagittal plane movements that are characteristic of many multidirectional sports. To examine the extent to which lower extremity biomechanics measured during a jump landing on a double leg (DL) after a sagittal plane (SAG) movement is representative of biomechanics measured during single-leg (SL) or frontal plane (FRONT) jump landing tasks. Controlled laboratory study. Lower extremity biomechanics were measured in 15 recreationally active females (mean age [±SD], 19.4 ± 2.1 years; mean height, 163.3 ± 5.9 cm; mean weight, 61.1 ± 7.1 kg) while performing SAGDL, SAGSL, FRONTDL, and FRONTSL jump landing tasks. Repeated-measures analyses of variance examined differences in lower extremity biomechanics between the 4 tasks, and linear regressions examined the extent to which an individual's biomechanics during SAGDL were representative of their biomechanics during SAGSL, FRONTDL, and FRONTSL. Lower extremity kinematics and kinetics differed by condition, with the SAGDL task generally eliciting greater hip and knee flexion angles and lower hip and knee forces than the other tasks (P plane jump landing tasks used to screen for ACL injury risk and the effectiveness of ACL injury prevention programs may not adequately represent the lower extremity biomechanics that occur during single-leg activities. These results support further investigation of single-leg multidirectional landings to identify high-risk movement strategies in female athletes playing multidirectional sports.

  2. Radiographic Restoration of Sagittal Spinopelvic Alignment After Posterior Lumbar Interbody Fusion in Degenerative Spondylolisthesis.

    Science.gov (United States)

    Kong, Ling-De; Zhang, Ying-Ze; Wang, Feng; Kong, Fan-Long; Ding, Wen-Yuan; Shen, Yong

    2016-03-01

    A retrospective study. This study was aimed to analyze the changes in spinopelvic parameters after surgical correction of degenerative spondylolisthesis and to determine which deformity is most responsible for changes in sagittal spinopelvic alignment. The basic deformities of degenerative spondylolisthesis are forward slippage of the vertebral body, segmental kyphotic angle, and loss of disk height. Correction of those deformities during surgery will subsequently affect the spinopelvic parameters. A few studies have reported the changes of sagittal spinopelvic alignment after surgical treatment of isthmic spondylolisthesis. However, there appears to be relatively little information regarding degenerative spondylolisthesis. Fifty-three patients with L4-L5 degenerative spondylolisthesis were included. All patients underwent posterior lumbar interbody fusion and posterior instrumentation. Back pain, as the clinical outcome, was evaluated by visual analogue scale (VAS). The preoperative and postoperative spinopelvic parameters, including sacral slope (SS), pelvic tilt (PT), lumbar lordosis (LL), and L1 axis S1 distance were measured, and then the correlations between spinopelvic parameters and local deformity parameters such as slip degree, slip angle (SA), and height of the intervertebral disk were evaluated. After surgical correction of local deformity, all spinopelvic parameters changed subsequently: PT and L1 axis S1 distance had a decrease, SS and LL had an increase. VAS score decreased from 6.1±2.3 before surgery to 2.4±1.7 at the final follow-up assessment. Patients with VAS score changes ≥3 showed significantly higher SS and LL, and lower PT compared with those with VAS score changes spondylolisthesis with posterior lumbar interbody fusion and posterior instrumentation resulted in relief of back pain, which may be associated with improvement of sagittal spinopelvic alignment. Surgeons should consider deformity parameters, especially the SA, in the surgical

  3. Direct repair of the sagittal band for extensor tendon subluxation caused by finger flicking.

    Science.gov (United States)

    Hong, In Tae; Oh, Chi Hoon; Sim, Young Suk; Han, Soo Hong

    2017-09-01

    For patients with metacarpophalangeal (MCP) extensor tendon subluxation caused by finger flicking injury, we performed an extensor tendon realignment and direct repair technique. The purpose of this study was to evaluate the clinical outcome after direct repair of the sagittal band in patients with MCP extensor tendon subluxation caused by finger flicking injury and to introduce the repair technique. A total of 26 patients with a mean age of 39.9 years were included in the study. The mean time from injury to surgery was 51.3 days. The ruptured sagittal band was reattached to the lateral side of the extensor tendon using a continuous interlocking suture. Patients were evaluated for pain using a visual analog scale (VAS), range of motion, long fingertip pinch strength, disabilities of the arm, shoulder, and hand (DASH) score, and the recurrence of extensor tendon subluxation or dislocation. All patients had full range of motion compared to the uninjured contralateral digit. Long fingertip pinch strength was also comparable to that of the contralateral digit in all patients. The DASH score was also improved from a preoperative average of 28.8 to a postoperative average of 1.0. Realignment of the extensor tendon and direct repair of the superficial layer of the sagittal band to the extensor digitorum communis (EDC) tendon is recommended as a treatment option in patients with chronic MCP extensor tendon subluxation, as well as for acute MCP extensor tendon subluxation in patients that have failed or could not maintain conservative treatment approaches.

  4. Intrinsic carpal ligaments on MR and multidetector CT arthrography: comparison of axial and axial oblique planes

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ryan K.L.; Griffith, James F.; Ng, Alex W.H.; Law, Eric K.C. [The Chinese University of Hong Kong, Department of Imaging and Interventional Radiology, Prince Of Wales Hospital, Hong Kong (China); Tse, W.L.; Wong, Clara W.Y.; Ho, P.C. [The Chinese University of Hong Kong, Department of Orthopedics and Traumatology, Prince Of Wales Hospital, Hong Kong (China)

    2017-03-15

    To compare axial and oblique axial planes on MR arthrography (MRA) and multidetector CT arthrography (CTA) to evaluate dorsal and volar parts of scapholunate (SLIL) and lunotriquetral interosseous (LTIL) ligaments. Nine cadaveric wrists of five male subjects were studied. The visibility of dorsal and volar parts of the SLIL and LTIL was graded semi-quantitatively (good, intermediate, poor) on MRA and CTA. The presence of a ligament tear was determined on arthrosocopy and sensitivity, specificity and accuracy of tear detection were calculated. Oblique axial imaging was particularly useful for delineating dorsal and volar parts of the LTIL on MRA with overall 'good' visibility increased from 11 % to 78 %. The accuracy of MRA and CTA in revealing SLIL and LTIL tear was higher using the oblique axial plane. The overall accuracy for detecting SLIL tear on CTA improved from 94 % to 100 % and from 89 % to 94 % on MRA; the overall accuracy of detecting LTIL tear on CTA improved from 89 % to 100 % and from 72 % to 89 % on MRA Oblique axial imaging during CT and MR arthrography improves detection of tears in the dorsal and volar parts of both SLIL and LTIL. (orig.)

  5. Sagittal standing posture, back pain, and quality of life among adults from the general population: a sex-specific association.

    Science.gov (United States)

    Araújo, Fábio; Lucas, Raquel; Alegrete, Nuno; Azevedo, Ana; Barros, Henrique

    2014-06-01

    A prospective radiographical study of sagittal standing posture among adults consecutively recruited from the general population. To analyze the relation of suboptimal sagittal standing posture with back pain and health-related quality of life in general adult males and females. Clinical studies have shown the association of sagittal standing posture with pain and reduced quality of life, but this relation has not been assessed in the general adult population. As part of the EPIPorto population-based study of adults, 178 males and 311 females were evaluated. Age, education, and body mass index were recorded. Radiographical data collection consisted of 36-in. standing sagittal radiographs. Creation of 3 groups for individual spinopelvic parameters was performed (low, intermediate, or high), and 1 of 4 sagittal types of postural patterns attributed to each participant (Roussouly classification). Back pain prevalence and severity were assessed on the basis of self-reported data and health-related quality of life using 2 main components of the 36-Item Short Form Health Survey. In males, differences in back pain severity were observed only among pelvic tilt/pelvic incidence ratio groups. Females presenting high pelvic incidence and sacral slope exhibited higher odds of severe back pain than those with intermediate values (adjusted odds ratios = 2.21 and 2.15; 95% confidence interval, 1.24-3.97 and 1.21-3.86; respectively). Sagittal vertical axis showed the largest differences in physical quality of life of females: high group had 8.8 lower score than the low group (P posture was not consistently associated with quality of life measures in males. Increased pelvic incidence and sacral slope may be involved in causing severe back pain among females. Monitoring sagittal postural parameters has limited usefulness as a screening tool for causes of unspecific musculoskeletal symptoms in the general adult population. 3.

  6. A clinico-radiographic analysis of sagittal condylar guidance determined by protrusive interocclusal registration and panoramic radiographic images in humans

    Directory of Open Access Journals (Sweden)

    D Krishna Prasad

    2012-01-01

    Full Text Available Purpose: To evaluate the correlation between sagittal condylar guidance obtained by protrusive interocclusal records and panoramic radiograph tracing methods in human dentulous subjects. Materials and Methods: The sagittal condylar guidance was determined in 75 dentulous subjects by protrusive interocclusal records using Aluwax through a face bow transfer (HANAU™ Spring Bow, Whip Mix Corporation, USA to a semi-adjustable articulator (HANAU™ Wide-Vue Articulator, Whip Mix Corporation, USA. In the same subjects, the sagittal outline of the articular eminence and glenoid fossa was traced in panoramic radiographs. The sagittal condylar path inclination was constructed by joining the heights of curvature in the glenoid fossa and the corresponding articular eminence. This was then related to the constructed Frankfurt′s horizontal plane to determine the radiographic angle of sagittal condylar guidance. Results: A strong positive correlation existed between right and left condylar guidance by the protrusive interocclusal method (P 0.000 and similarly by the radiographic method (P 0.013. The mean difference between the condylar guidance obtained using both methods were 1.97° for the right side and 3.18° for the left side. This difference between the values by the two methods was found to be highly significant for the right (P 0.003 and left side (P 0.000, respectively. The sagittal condylar guidance obtained from both methods showed a significant positive correlation on right (P 0.000 and left side (P 0.015, respectively. Conclusion: Panoramic radiographic tracings of the sagittal condylar path guidance may be made relative to the Frankfurt′s horizontal reference plane and the resulting condylar guidance angles used to set the condylar guide settings of semi-adjustable articulators.

  7. Central uplift of custom immobilization radiotherapy patients with lower limb overhead sagittal laser affected without mobile

    International Nuclear Information System (INIS)

    Velazquez Miranda, S.; Delgado Gil, M. M.; Ortiz Seidel, M.

    2011-01-01

    If you have a laser moving overhead sagittal or the location of tumors in the lower extremities is laborious, as to reference properly in the CT, is necessary before tattooing in the treatment table using their ability to relate the lateral midline with tattoos on the limb. For anatomical forms often happens that lasers are not displayed on the areas of our interest. The problem can be overcome if between the legs raise the bag or custom immobilizer above the height of the patient's abdomen, as this will have a central reference reliable and well designed lasers.

  8. Using smartphones in the evaluation of spinal curvatures in a sagittal plane

    Directory of Open Access Journals (Sweden)

    Waś Jakub

    2016-12-01

    Full Text Available Introduction: In physiotherapeutic diagnostic processes, various tools and methods may be used. However, price and availability may limit their daily use in clinical practice. Therefore, the suggestion that smartphones with specific applications may be useful as diagnostic tools can be found in the literature. However, before using them in clinical practice, it is important to verify their reliability. The aim of the study was to evaluate the consistency of measurements of the curvatures in the sagittal plane performed with the Saunders digital inclinometer and a smartphone application.

  9. An incidental persistent falcine sinus with dominant straight sinus and hypoplastic distal superior sagittal sinus

    Energy Technology Data Exchange (ETDEWEB)

    Manoj, Krishnan Sarojam [Metroscans, Trivandrum (India); Krishnamoorthy, Thamburaj; Thomas, Bejoy; Kapilamoorthy, Tirur Raman [Sree Chitra Tirunal Institute for Medical Sciences and Technology, Department of Imaging Sciences and Interventional Radiology, Trivandrum (India)

    2006-01-01

    An incidental persistent falcine sinus was detected in an otherwise normal brain on MRI in a 12-year-old girl who underwent imaging after clinical suspicion of acute disseminated encephalomyelitis. The falcine sinus was associated with a hypoplastic posterior third of the superior sagittal sinus and a dominant straight sinus. Generally, atresia or hypoplasia of the straight sinus is associated with a persistent falcine sinus in postnatal life; otherwise, the falcine sinus disappears before birth. We discuss the embryological basis for such an association in this case. (orig.)

  10. Papilledema secondary to a superior sagittal sinus thrombosis. Mantle cell lymphoma paraneoplastic syndrome.

    Science.gov (United States)

    Platas-Moreno, I; Antón-Benito, A; Pérez-Cid-Rebolleda, M T; Rosado Sierra, M B

    2016-01-01

    A 46 year old patient presented with visual loss in the left eye during the previous months. Ophthalmoscopic examination and magnetic resonance angiography found the presence of papilledema due to thrombosis in superior sagittal sinus. The examination findings revealed a mantle cell lymphoma. Cerebral venous thrombosis is an unusual cause of papilledema. This type of thrombosis may be secondary to hyper-viscosity within a context of a paraneoplastic syndrome. Copyright © 2015 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

  11. Axial flow heat exchanger devices and methods for heat transfer using axial flow devices

    Science.gov (United States)

    Koplow, Jeffrey P.

    2016-02-16

    Systems and methods described herein are directed to rotary heat exchangers configured to transfer heat to a heat transfer medium flowing in substantially axial direction within the heat exchangers. Exemplary heat exchangers include a heat conducting structure which is configured to be in thermal contact with a thermal load or a thermal sink, and a heat transfer structure rotatably coupled to the heat conducting structure to form a gap region between the heat conducting structure and the heat transfer structure, the heat transfer structure being configured to rotate during operation of the device. In example devices heat may be transferred across the gap region from a heated axial flow of the heat transfer medium to a cool stationary heat conducting structure, or from a heated stationary conducting structure to a cool axial flow of the heat transfer medium.

  12. DISPELLING ILLUSIONS OF REFLECTION: A NEW ANALYSIS OF THE 2007 MAY 19 CORONAL 'WAVE' EVENT

    International Nuclear Information System (INIS)

    Attrill, Gemma D. R.

    2010-01-01

    A new analysis of the 2007 May 19 coronal wave-coronal mass ejection-dimmings event is offered employing base difference extreme-ultraviolet (EUV) images. Previous work analyzing the coronal wave associated with this event concluded strongly in favor of purely an MHD wave interpretation for the expanding bright front. This conclusion was based to a significant extent on the identification of multiple reflections of the coronal wave front. The analysis presented here shows that the previously identified 'reflections' are actually optical illusions and result from a misinterpretation of the running difference EUV data. The results of this new multiwavelength analysis indicate that two coronal wave fronts actually developed during the eruption. This new analysis has implications for our understanding of diffuse coronal waves and questions the validity of the analysis and conclusions reached in previous studies.

  13. Theoretical axial wall angulation for rotational resistance form in an experimental-fixed partial denture.

    Science.gov (United States)

    Bowley, John Francis; Kaye, Elizabeth Krall; Garcia, Raul Isidro

    2017-08-01

    The aim of this study was to determine the influence of long base lengths of a fixed partial denture (FPD) to rotational resistance with variation of vertical wall angulation. Trigonometric calculations were done to determine the maximum wall angle needed to resist rotational displacement of an experimental-FPD model in 2-dimensional plane. The maximum wall angle calculation determines the greatest taper that resists rotation. Two different axes of rotation were used to test this model with five vertical abutment heights of 3-, 3.5-, 4-, 4.5-, and 5-mm. The two rotational axes were located on the mesial-side of the anterior abutment and the distal-side of the posterior abutment. Rotation of the FPD around the anterior axis was counter-clockwise, Posterior-Anterior (P-A) and clockwise, Anterior-Posterior (A-P) around the distal axis in the sagittal plane. Low levels of vertical wall taper, ≤ 10-degrees, were needed to resist rotational displacement in all wall height categories; 2-to-6-degrees is generally considered ideal, with 7-to-10-degrees as favorable to the long axis of the abutment. Rotation around both axes demonstrated that two axial walls of the FPD resisted rotational displacement in each direction. In addition, uneven abutment height combinations required the lowest wall angulations to achieve resistance in this study. The vertical height and angulation of FPD abutments, two rotational axes, and the long base lengths all play a role in FPD resistance form.

  14. Jump distance of dance landings influencing internal joint forces: I. Axial forces.

    Science.gov (United States)

    Simpson, K J; Kanter, L

    1997-07-01

    Knowledge of the magnitude and rate of applying axial forces (AF) during actual dance movements is necessary for understanding the etiology of chronic injuries and osteoarthritis. The purpose of this study was to investigate the effect of jumping distance on component ankle and knee joint AFs generated during the landing phase of traveling jumps. Six female dancers performed 10 jumps each at 30, 60, and 90% maximum jump distance (JD) and 15 jumps ranging from 35 to 100% JD. A sagittal view of the right leg landing onto a force platform was filmed. Greater ground reaction force maxima, knee flexion, knee and ankle flexion velocity, tibial landing angle, net ankle and knee joint moment maxima, ankle and knee joint reaction AFs, and quadriceps AFs (QuadAF) peak magnitudes and rates of AF application (dFmax/dt) were observed (P JD. The QuadAF was a more important determinant of knee AF than joint reaction AF. Increased quadriceps force was useful for accommodating impact forces but served to increase its contribution to Knee AF, particularly during the later portion of the impact phase. High impact situations create significant magnitudes (e.g., 14 BW) and dFmax/dt of muscle AFs which could contribute to excessive joint wear.

  15. Reducing Variability in Orthogonal Reformatted Image Quality Associated With Axial Long-z-Axis CT Angiography.

    Science.gov (United States)

    Stein, Erica B; Liu, Peter S; Kazerooni, Ella A; Barber, Karen; Davenport, Matthew S

    2016-12-01

    The objective of our study was to reduce variation in image quality of orthogonal reformatted images generated from long-z-axis CT angiography (CTA) studies of the upper and lower extremities. Upper and lower extremity CTA studies were targeted at a single health care system. A correctly performed CTA examination was defined as one that met the following three criteria: Sagittal and coronal reformats were obtained, a high-resolution matrix greater than 512 × 512 was used, and reformatted images were available in a distance-measurable format. Baseline data were collected from February 1, 2014, through September 30, 2014. Corrective actions were implemented during three consecutive plan-do-check-act (PDCA) cycles from October 1, 2014, through July 31, 2015, that addressed human, technical, and systematic variations. A 3-month maintenance period followed in which no intervention was performed. Longitudinal data were analyzed monthly using a statistical process control chart (p-chart). The total number of long-z-axis extremity CTA studies analyzed was as follows: 351 CTA studies were analyzed at baseline, 94 at the first PDCA cycle, 92 at the second PDCA cycle, 114 at the third PDCA cycle, and 138 during the maintenance period. The monthly rate of correctly performed studies ranged from 7% to 51% (mean, 38% ± 13% [SD]) during the baseline period, 32-59% (mean, 46% ± 14%) during the first PDCA cycle, 40-81% (mean, 61% ± 21%) during the second PDCA cycle, and 80-82% (mean, 81% ± 0.9%) during the third PDCA cycle. The monthly rate improved to 90-91% (mean, 91% ± 0.5%) during the maintenance period. The upper and lower control limits of the p-chart were upshifted after the second and third PDCA cycles. Correcting systematic and technical variations led to the greatest improvements in reformat accuracy. Obtaining consistently and correctly reformatted images from long-z-axis CTA studies is achievable using iterative PDCA cycles.

  16. QCD plasma parameters in axial gauge

    Energy Technology Data Exchange (ETDEWEB)

    Nachbagauer, H. (Technische Univ., Vienna (Austria). Inst. fuer Theoretische Physik)

    1992-11-01

    Within the framework of imaginary time formalism we investigate the structure of the gluon polarization tensor and relate its structure functions to the dispersion relation of plasma eigenmodes. To one loop order, we calculate the transversal structure function to leading order in the high temperature expansion as well as the first subleading order contribution in the long wavelength limit. The result is used to express the dynamical mass and the damping constant for transversal plasma eigenmodes. The aim of our present paper is a systematic discussion of the gauge fixing vector dependence of the damping constant. In the limit of temporal axial gauge we encounter a negative damping constant contradicting previous results. (orig.).

  17. QCD plasma parameters in axial gauge

    Science.gov (United States)

    Nachbagauer, Herbert

    1992-09-01

    Within the framework of imaginary time formalism we investigate the structure of the gluon polarization tensor and relate its structure functions to the dispersion relation of plasma eigenmodes. To one loop order, we calculate the transversal structure function to leading order in the high temperature expansion as well as the first subleading order contribution in the long wavelength limit. The result is used to express the dynamical mass and the damping constant for transversal plasma eigenmodes. The aim of our present paper is a systematic discussion of the gauge fixing vector dependence of the damping constant. In the limit of temporal axial gauge we encounter a negative damping constant contradicting previous results.

  18. Disordered axial movement in Parkinson's disease.

    OpenAIRE

    Steiger, M J; Thompson, P D; Marsden, C D

    1996-01-01

    Axial motor impairments are a common cause of disability in patients with Parkinson's disease, become more prominent with longer disease duration, and have been said to be less responsive to levodopa replacement therapy. The ability to turn in bed while lying supine before and after dopaminergic stimulation was studied in a group of 36 patients with Parkinson's disease; 23 were in Hoehn and Yahr stages 3-5 when "off", and 13 were in stages 1-2. Turning was also compared with postural stabilit...

  19. Water ingestion into jet engine axial compressors

    Science.gov (United States)

    Tsuchiya, T.; Murthy, S. N. B.

    1982-01-01

    An axial flow compressor has been tested with water droplet ingestion under a variety of conditions. The results illustrate the manner in which the compressor pressure ratio, efficiency and surging characteristics are affected. A model for estimating the performance of a compressor during water ingestion has been developed and the predictions obtained compare favorably with the test results. It is then shown that with respect to five droplet-associated nonlinearly-interacting processes (namely, droplet-blade interactions, blade performance changes, centrifugal action, heat and mass transfer processes and droplet break-up), the initial water content and centrifugal action play the most dominant roles.

  20. Ankylosing Spondylitis versus Nonradiographic Axial Spondyloarthritis

    DEFF Research Database (Denmark)

    Glintborg, Bente; Sørensen, Inge J; Østergaard, Mikkel

    2017-01-01

    OBJECTIVE: To compare baseline disease activity and treatment effectiveness in biologic-naive patients with nonradiographic axial spondyloarthritis (nr-axSpA) and ankylosing spondylitis (AS) who initiate tumor necrosis factor inhibitor (TNFi) treatment and to study the role of potential confounders....../disease duration/TNFi-type/smoking/baseline disease activity) on TNFi adherence and response [e.g., Bath Ankylosing Spondylitis Activity Index (BASDAI) 50%/20 mm]. RESULTS: The study included 1250 TNFi-naive patients with axSpA (29% nr-axSpA, 50% AS, 21% lacked radiographs of sacroiliac joints). Patients...

  1. Cervical Spine Axial Rotation Goniometer Design

    Directory of Open Access Journals (Sweden)

    Emin Ulaş Erdem

    2012-06-01

    Full Text Available To evaluate the cervical spine rotation movement is quiet harder than other joints. Configuration and arrangement of current goniometers and devices is not always practic in clinics and some methods are quiet expensive. The cervical axial rotation goniometer designed by the authors is consists of five pieces (head apparatus, chair, goniometric platform, eye pads and camera. With this goniometer design a detailed evaluation of cervical spine range of motion can be obtained. Besides, measurement of "joint position sense" which is recently has rising interest in researches can be made practically with this goniometer.

  2. Prenatal MR imaging of Dandy-Walker complex: Midline sagittal area analysis

    International Nuclear Information System (INIS)

    Wong, Alex M.; Bilaniuk, Larissa T.; Zimmerman, Robert A.; Liu, P.L.

    2012-01-01

    Objective: To measure the mid-sagittal areas of vermis (VA) and of posterior fossa (PFA) and determine their differences among fetuses with various Dandy-Walker (DW) entities and control subjects. Methods: We reviewed data in 25 fetal patients with a MR diagnosis of DW complex including hypoplastic vermis (HV), HV with rotation (HVR), and mega cistern magna (MCM), and in 85 fetal controls with normal CNS. PFA and VA of each subject were manually traced on mid-sagittal MR images. Regarding each of VA and PFA, after age correction, we determined statistically significant differences among HVR, HV, MCM, and control groups. Results: The mean VA residue of MCM was greater than that of the control, which was in turn greater than those of HVR and HV. The mean PF residue of the control was smaller than all other groups. Conclusion: Fetuses with HVR or HV had smaller VA than fetuses with MCM or control subjects. Fetuses with MCM, HVR, or HV had larger PFA than control subjects. These results may be an early step leading to better understanding of the confusion about the PF anomalies in future.

  3. Skull fracture with effacement of the superior sagittal sinus following drone impact: a case report.

    Science.gov (United States)

    Chung, Lawrance K; Cheung, Yuri; Lagman, Carlito; Au Yong, Nicholas; McBride, Duncan Q; Yang, Isaac

    2017-09-01

    The popularity of unmanned aerial vehicles, or drones, raises safety concerns as they become increasingly common for commercial, personal, and recreational use. Collisions between drones and people may result in serious injuries. A 13-year-old male presented with a comminuted depressed skull fracture causing effacement of the superior sagittal sinus secondary to a racing drone impact. The patient experienced a brief loss of consciousness and reported lower extremity numbness and weakness after the accident. Imaging studies revealed bone fragments crossing the superior sagittal sinus with a short, focal segment of blood flow interruption. Neurosurgical intervention was deferred given the patient's improving neurological deficits, and the patient was treated conservatively. He was discharged home in stable condition. Drones may represent a hazard when operated inappropriately due to their capacity to fly at high speeds and altitudes. Impacts from drones can carry enough force to cause skull fractures and significant head injuries. The rising popularity of drones likely translates to an increased incidence of drone-related injuries. Thus, clinicians should be aware of this growing trend.

  4. Flow velocity of the superior sagittal sinus is reduced in patients with idiopathic normal pressure hydrocephalus.

    Science.gov (United States)

    Kuriyama, Nagato; Tokuda, Takahiko; Yamada, Kei; Akazawa, Kentaro; Hosoda, Makoto; Sakai, Koji; Watanabe, Yoshiyuki; Nakagawa, Masanori

    2011-10-01

    The pathogenesis and diagnostic methods for idiopathic normal pressure hydrocephalus (iNPH) have been active areas of research in recent years. This study was performed to determine whether there is a venous return abnormality in the intracranial circulation of patients with iNPH. The subjects were 20 patients with iNPH (Group N) and 24 normal controls (Group C). MR venography (MRV) was performed at the superior sagittal sinus 2 cm above the confluence of the sinuses, and the flow velocities were compared between Groups N and C. During normal breathing, the maximum velocities were significantly lower in Group N (18.8 cm/second) than in Group C (22.9 cm/second; (P velocity decreased in both groups, but both the maximum (Max V) and minimum (Min V) velocities were significantly lower in Group N than in Group C (P velocity at the superior sagittal sinus was lower and the flow velocity during the Valsalva maneuver decreased more in patients with iNPH than in controls. The results may reflect the presence of abnormal intracranial venous flow in iNPH. © 2010 by the American Society of Neuroimaging.

  5. Novel Angular Measures of Cervical Deformity Account for Upper Cervical Compensation and Sagittal Alignment.

    Science.gov (United States)

    Protopsaltis, Themistocles S; Lafage, Renaud; Vira, Shaleen; Sciubba, Daniel; Soroceanu, Alex; Hamilton, Kojo; Smith, Justin; Passias, Peter G; Mundis, Gregory; Hart, Robert; Schwab, Frank; Klineberg, Eric; Shaffrey, Christopher; Lafage, Virginie; Ames, Christopher

    2017-08-01

    This is a retrospective review of a prospective multicenter database. This study introduces 2 new cervical alignment measures accounting for both cervical deformity (CD) and upper cervical compensation. Current descriptions of CD like the C2-C7 sagittal vertical axis (cSVA) do not account for compensatory mechanisms such as C0-C2 lordosis and pelvic tilt, which makes surgical planning difficult. The craniocervical angle (CCA) combines the slope of McGregor's line and the inclination from C7 to the hard palate. The C2-pelvic tilt (CPT) combines C2 tilt and pelvic tilt. Like the T1 pelvic angle, CPT is less affected by lower extremity and pelvic compensation. Novel and existing CD measures were correlated in 781 patients from a thoracolumbar deformity (TLD) database and 61 patients from a prospective CD database. CD patients were subanalyzed by region of deformity driver: cervical or cervico-thoracic junction. TLD patients were substratified according to whether or not they had CD as well, where CD was defined as cSVA>4 cm or T1 slope minus cervical lordosis mismatch (TS-CL) >20. TLD cohort: mean cSVA was 31.7±17.8 mm. Subanalysis of TLD patients with CD versus no-CD demonstrated significant differences in CCA (56.2 vs. 60.6, Paccount for both cervical sagittal alignment and upper cervical compensation and can be utilized in assessment of cervical alignment.

  6. Risk factors for breakage of biodegradable plate systems after bilateral sagittal split mandibular setback surgery.

    Science.gov (United States)

    Yoshioka, Izumi; Igawa, Kaori; Nagata, Jyunko; Yoshida, Maho; Baba, Takashi; Ichiki, Takeshi; Kondoh, Yudai; Takamori, Koichi; Kashima, Koji; Sakoda, Sumio

    2013-06-01

    The aim of this retrospective study was to evaluate the risk factors associated with breakage of biodegradable plate systems after bilateral sagittal split mandibular setback. We studied 169 Japanese adults (62 men, 107 women; age range 16-53 years) with deformities of the jaw diagnosed as mandibular prognathism. All patients were treated by bilateral sagittal split osteotomy (BSSO) with 2 biodegradable fixation plates and screws at the anterior mandibular ramus. We collected the following data from the medical records and radiological findings: sex; age; degree of setback; presence of asymmetry; presence of open bite; operation; design of the plate; operating time; and blood loss. Multiple logistic regression analysis was used to find the factors that were independently associated with the dependent variable: breakage of the biodegradable plate system. In 10 of the 169 patients (6%) the biodegradable plate system for the BSSO broke. Factors that influenced whether or not the biodegradable plate system fractured were if they were asymmetrical (odds ratio (OR) 5.35; P=0.02) and had an open bite (OR 5.20; P=0.02). Asymmetry or open bite was significantly associated with breaks in the biodegradable plate system. Biodegradable plates should be used only when loading is minimal. Copyright © 2012 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  7. Normal development of brainstem in childhood. Measurement of the area on mid-sagittal MR imaging

    International Nuclear Information System (INIS)

    Kutomi, Kimiko

    2005-01-01

    Developmental abnormality of brainstem is shown in pediatric patients with mental retardation, autism, periventricular leukomalacia, neurodegenerative disease, and so on. Our purpose here is to clarify the normal developmental pattern of the brainstem. We measured the area of tectum, midbrain tegmentum, pons, basis pontis and pontine tegmentum on mid-sagittal MR images in 111 children (newborn to 20 year old). Different growth patterns were shown in all parts of the brainstem. Tectum showed a subtle increase in area from the newborn to adult period, while midbrain tegmentum and pontine tegmenturn showed a mild and gradual increase in area. Pons and pontine tegmentum showed a rapid and prominent increase in area from newborn to infant period and gradual increase in area until the adult period. These different growth patterns seemed to be consistent with differences in the myelination cycles of the neuronal fibers, maturation of the nuclei and proliferation of glial cells in each part of the brainstem. Mid-sagittal MR imaging of the head is accurate and reproducible and is used conveniently in routine head MR study, making it very useful for the diagnosis of many central nervous diseases and anomalies. We believe that this new milestone provided in this study will be helpful in distinguishing normal children from those that have neurodegenerative disorders. (author)

  8. Current concepts on the sagittal balance and classification of spondylolysis and spondylolisthesis☆☆☆

    Science.gov (United States)

    Tebet, Marcos Antonio

    2014-01-01

    Treatment of spondylolysis and spondylolisthesis remains a challenge for orthopaedic surgeons, neurosurgeons and paediatrics. In spondylolisthesis, it has been clearly demonstrated over the past decade that spino-pelvic morphology is abnormal and that it can be associated to an abnormal sacro-pelvic orientation as well as to a disturbed global sagittal balance of spine. This article presents the SDSG (Spinal Deformity Study Group) classification of lumbosacral spondylolisthesis. The proper treatment of spondylolisthesis is dependent on recognizing the type of slip, sacro-pelvic balance and overall sagittal balance and its natural history. Although a number of clinical radiographic features have been identified as risk factors, their role as primary causative factors or secondary adaptative changes is not clear. The conservative treatment of adult isthmic spondylolisthesis results in good outcome in the majority of cases. Of those patients who fail conservative treatment, success with surgery is quite good, with significant improvement in neurologic function in those patients with deficits, as well as improvement in patients with back pain. PMID:26229765

  9. Measuring the Reliability of Sagittal Facial Anthropometric Measurements under Soft Tissue Displacement Using a Modified Ruler

    Directory of Open Access Journals (Sweden)

    Faramarz Mojtahedzadeh

    2013-01-01

    Full Text Available Objective: Despite the current use of radiography for quantifying sagittal skeletal measurements, it is an unsuitable way for screening or epidemiologic purposes. Although not fully approved, anthropometric measurements have been suggested as a substitute, and considering displacement of soft tissues, could possibly lead to more consistent results. The purpose of this study was to evaluate the reliability of anthropometric anteroposterior facial measurements under soft tissue compression using a special ruler.Material and Methods: Anthropometric measurements were done with a specifically designed sliding ruler twice on 36 adult patients with a 14 day lag between two measurements. The ruler measured the distance between the external acoustic meatus and the nasion (Na, subnasal (Sn point and the soft tissue pogonion (Pog. The soft tissue was displaced during measurements only to the extent that the underlying hard tissue resistance was felt subjectively by each assessor. The intraclass correlation coefficient (ICC was calculated for both inter- and intra- rater measurements using SPSS software.Results: All measurements had inter- and intrarater agreements above 0.9, with only a few parameters having lower bound confidence intervals below 0.9, but more than 0.8.Conclusion: Sagittal facial anthropometric measurements under soft tissue displacement using the specific ruler are valid and reliable and could possibly aid orthodontists in chairside craniofacial assessments.

  10. Sagittal Alignment as Predictor of Adjacent Segment Disease After Lumbar Transforaminal Interbody Fusion.

    Science.gov (United States)

    Sun, Jin; Wang, Jun-Jie; Zhang, Li-Wei; Huang, Hui; Fu, Na-Xin

    2018-02-01

    This study was carried out to explore the diagnostic value of sagittal measurements for adjacent segment disease after lumbar transforaminal interbody fusion (TLIF). A total of 163 subjects who underwent TLIF for lumbar disease were initially enrolled in the study from July 2013 to August 2017. Sagittal alignment including thoracic inlet and spinopelvic parameters was measured by using preoperative full-length freestanding radiographs. Multivariate logistic regression analysis was performed to evaluate these parameters as the diagnostic index for adjacent segment disease (ASD). A total of 153 patients completed the final follow-up, and the mean follow-up period was 40.6 months. There were 53 (35.3%) cases with ASD found after the TLIF in the enrolled subjects. Logistic regression analysis and receiver operating characteristic analysis confirmed that preoperative pelvic tilt (PT) of more than 24.1° and thoracic kyphosis (TK) of more than 23.3° were significant risk factors of ASD after TLIF (P < 0.05). We confirmed that PT of more than 24.3° and TK of more than 23.3° could be regarded as predictors of ASD after lumbar TLIF. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Sagittal MR findings of L5 spondylolysis : changes of spinal canal

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hyun Cheol; Choi, Woo Suk; Kim, Eui Jong; Ryu, Kyung Nam; Oh, Joo Hyeong; Kim, Ihn Sub; Yoon, Yup [Kyunghee Univ. Hospital, Seoul (Korea, Republic of)

    1997-07-01

    To evaluate changes in the spinal canal in cases of L5 spondylolysis, as seen on sagittal MR images. We retrospectively analysed the MR findings of 27 patients suffering from L5 spondylolysis without spondylolisthesis and compared them with 100 control subjects. Spondylolysis had been confirmed by conventional radiography. On midsagittal MR images, sagittal canal ratio (SCR) was defined as midsagittal canal diameter at L5 devided by that at L1. We analysed the frequency of posterior epidural fat deposition(posterior epidural fat between the posterior margin of the dural sac and the anterior cortical margin of the spinous process on the midsagittal line), and compared this with the frequency in 100 control subjects. Mean SCR value in 27 patients with L5 spondylolysis(1.22) was significantly greater than 100 control subjects(0.96, p<0.001). Mean SCR value in 17 patients with L5 spondylolysis and posterior epidural fat deposition(1.27) was significantly higher than in nine control subjects with posterior epidural fat deposition(0.97). Posterior epidural fat deposition was more frequently indentified in patients with L5 spondylolysis(63%) than in control subjects(9%). The possibility of L5 spondylolysis is suggested when on midsaggital MR imaging, the anteroposterior diameter of the L5 spinal canal is seen to be widened and posterior epidural fat deposition is noted.

  12. Sagittal MR findings of L5 spondylolysis : changes of spinal canal

    International Nuclear Information System (INIS)

    Kim, Hyun Cheol; Choi, Woo Suk; Kim, Eui Jong; Ryu, Kyung Nam; Oh, Joo Hyeong; Kim, Ihn Sub; Yoon, Yup

    1997-01-01

    To evaluate changes in the spinal canal in cases of L5 spondylolysis, as seen on sagittal MR images. We retrospectively analysed the MR findings of 27 patients suffering from L5 spondylolysis without spondylolisthesis and compared them with 100 control subjects. Spondylolysis had been confirmed by conventional radiography. On midsagittal MR images, sagittal canal ratio (SCR) was defined as midsagittal canal diameter at L5 devided by that at L1. We analysed the frequency of posterior epidural fat deposition(posterior epidural fat between the posterior margin of the dural sac and the anterior cortical margin of the spinous process on the midsagittal line), and compared this with the frequency in 100 control subjects. Mean SCR value in 27 patients with L5 spondylolysis(1.22) was significantly greater than 100 control subjects(0.96, p<0.001). Mean SCR value in 17 patients with L5 spondylolysis and posterior epidural fat deposition(1.27) was significantly higher than in nine control subjects with posterior epidural fat deposition(0.97). Posterior epidural fat deposition was more frequently indentified in patients with L5 spondylolysis(63%) than in control subjects(9%). The possibility of L5 spondylolysis is suggested when on midsaggital MR imaging, the anteroposterior diameter of the L5 spinal canal is seen to be widened and posterior epidural fat deposition is noted

  13. Incomplete oblique sagittal fractures of the dorsal cortex of the third metacarpal bone in six horses

    International Nuclear Information System (INIS)

    Watt, B.C.; Foerner, J.J.; Haines, G.R.

    1998-01-01

    To describe incomplete oblique sagittal dorsal cortical fractures of the equine third metacarpal bone, their surgical repair, and subsequent performance of the horses. Retrospective examination of medical records and racing performance. Six Thoroughbred race horses, 2 to 4 years of age. Radiographic confirmation of all fractures preceded general anesthesia and surgical correction. Three fractures were treated by intracortical compression using screws placed in lag fashion, and five fractures were treated by osteostixis. Race records were reviewed for each horse to determine performance after surgery. Fractures were best observed on palmarodorsal radiographic projections. Three horses treated by intracortical compression returned to racing, but fracture recurred in one horse and was treated by osteostixis. This horse and the other three horses treated by osteostixis raced after surgery. Horses with incomplete oblique sagittal fractures of the dorsal cortex of the third metacarpal bone can race after surgical management of the fracture by screws placed in lag fashion or osteostixis. The authors' preferred surgical procedure for managing this fracture is osteostixis. Palmarodorsal radiographic projections of the third metacarpal bone are recommended in young Thoroughbred race horses suspected of having dorsal metacarpal stress fractures

  14. Preliminary results of anterior lumbar interbody fusion, anterior column realignment for the treatment of sagittal malalignment.

    Science.gov (United States)

    Hosseini, Pooria; Mundis, Gregory M; Eastlack, Robert K; Bagheri, Ramin; Vargas, Enrique; Tran, Stacie; Akbarnia, Behrooz A

    2017-12-01

    OBJECTIVE Sagittal malalignment decreases patients' quality of life and may require surgical correction to achieve realignment goals. High-risk posterior-based osteotomy techniques are the current standard treatment for addressing sagittal malalignment. More recently, anterior lumbar interbody fusion, anterior column realignment (ALIF ACR) has been introduced as an alternative for correction of sagittal deformity. The objective of this paper was to report clinical and radiographic results for patients treated using the ALIF-ACR technique. METHODS A retrospective study of 39 patients treated with ALIF ACR was performed. Patient demographics, operative details, radiographic parameters, neurological assessments, outcome measures, and preoperative, postoperative, and mean 1-year follow-up complications were studied. RESULTS The patient population comprised 39 patients (27 females and 12 males) with a mean follow-up of 13.3 ± 4.7 months, mean age of 66.1 ± 11.6 years, and mean body mass index of 27.3 ± 6.2 kg/m 2 . The mean number of ALIF levels treated was 1.5 ± 0.5. Thirty-three (84.6%) of 39 patients underwent posterior spinal fixation and 33 (84.6%) of 39 underwent posterior column osteotomy, of which 20 (60.6%) of 33 procedures were performed at the level of the ALIF ACR. Pelvic tilt, sacral slope, and pelvic incidence were not statistically significantly different between the preoperative and postoperative periods and between the preoperative and 1-year follow-up periods (except for PT between the preoperative and 1-year follow-up, p = 0.018). Sagittal vertical axis, T-1 spinopelvic inclination, lumbar lordosis, pelvic incidence-lumbar lordosis mismatch, intradiscal angle, and motion segment angle all improved from the preoperative to postoperative period and the preoperative to 1-year follow-up (p < 0.05). The changes in motion segment angle and intradiscal angle achieved in the ALIF-ACR group without osteotomy compared with the ALIF-ACR group with osteotomy

  15. Validity of a smartphone protractor to measure sagittal parameters in adult spinal deformity.

    Science.gov (United States)

    Kunkle, William Aaron; Madden, Michael; Potts, Shannon; Fogelson, Jeremy; Hershman, Stuart

    2017-10-01

    Smartphones have become an integral tool in the daily life of health-care professionals (Franko 2011). Their ease of use and wide availability often make smartphones the first tool surgeons use to perform measurements. This technique has been validated for certain orthopedic pathologies (Shaw 2012; Quek 2014; Milanese 2014; Milani 2014), but never to assess sagittal parameters in adult spinal deformity (ASD). This study was designed to assess the validity, reproducibility, precision, and efficiency of using a smartphone protractor application to measure sagittal parameters commonly measured in ASD assessment and surgical planning. This study aimed to (1) determine the validity of smartphone protractor applications, (2) determine the intra- and interobserver reliability of smartphone protractor applications when used to measure sagittal parameters in ASD, (3) determine the efficiency of using a smartphone protractor application to measure sagittal parameters, and (4) elucidate whether a physician's level of experience impacts the reliability or validity of using a smartphone protractor application to measure sagittal parameters in ASD. An experimental validation study was carried out. Thirty standard 36″ standing lateral radiographs were examined. Three separate measurements were performed using a marker and protractor; then at a separate time point, three separate measurements were performed using a smartphone protractor application for all 30 radiographs. The first 10 radiographs were then re-measured two more times, for a total of three measurements from both the smartphone protractor and marker and protractor. The parameters included lumbar lordosis, pelvic incidence, and pelvic tilt. Three raters performed all measurements-a junior level orthopedic resident, a senior level orthopedic resident, and a fellowship-trained spinal deformity surgeon. All data, including the time to perform the measurements, were recorded, and statistical analysis was performed to

  16. Expansion and broadening of coronal loop transients: A theoretical explanation

    International Nuclear Information System (INIS)

    Mouschovias, T.C.; Poland, A.I.

    1978-01-01

    We explore the consequences of the assumption that a coronal loop transient (observed by the white-light coronagraph aboard Skylab) is a twisted rope of magnetic field lines expanding and broadening in the background coronal plasma and magnetic field. We show that the expansion (i.e., the outward motion of the loop top) can be accounted for by the azimuthal component of the field, B/sub az/; the observed broadening of the loop as it moves outward can be accounted for by the longitudinal component of the field, B/sub l/. In order to have a net outward force and at the same time avoid a classicial pinch (sausage) instability, the two components of the field must satisfy the inequality 1.41 B/sub l/>B/sub az/>B/sub l/.We predict that, as the loop rises, the width (h) of its top portion should vary proportionally with the distance (R) from the Sun's center. This is in good agreement with measurements that show hproportionalR/sup 0.8/. Our prediction, that the radius of curvature (R/sub c/) of the top portion of the loop should be proportional to R, differs from the measured variation R/sub c/proportionalR/sup 1.6/. The difference could be accounted for by a drag due to the background coronal field that flattens the loop's top. A statistical study that can test this possibility is suggested. We also calculate the magnetic field within the top section of the loop. It is approximately equal to 1 gauss at R=2 R/sub sun/ and varies somewhat more slowly than R -2 during expansion

  17. Coronal pulp biomarker: A lesser known age estimation modality

    Directory of Open Access Journals (Sweden)

    Smrithi D Veera

    2014-01-01

    Full Text Available Introduction: The evolving state of art digital technology currently available is opening new avenues in forensic odontology for age estimation methods which are subject to debate in terms of accuracy and precision. A study was carried to analyze efficacy and practical application for age estimation using digital panoramic radiographs on South Indian population. Aims and Objectives: 1. To study reduction of coronal pulp chamber using Tooth Coronal Index (TCI on panoramic radiographs and correlate with chronologic age. 2. To establish accuracy of digital panoramic radiographs as a simple, non-invasive tool. Materials and Methods: The study illustrates the potential value of a little known aging method. The study groups comprised a total of 100 subjects of both sexes in age range of 20 and 60 years each who were subjected to panoramic radiography. A panoramic radiographic examination using digital panoramic machine was conducted on selected individuals. The TCI was calibrated using AGFA computer software for accuracy and precision. The values obtained were subjected to regression analysis, results calculated and correlated with chronologic age. In the present study a population of known age was studied and subjected to digital panoramic radiographic examination. The correlation between reduction of coronal pulp cavity and chronological age was examined. TCI was computed for each tooth and regressed on real age. Statistical Analysis Used: Pearson correlation co-efficient was used to find the significance of relationship between age and TCI. Regression analysis has been used for predicting age using TCI for premolar and molar. Inaccuracy and bias have been determined to assess the precision of prediction equations. Results and Conclusion: Prediction potential of TCI comes down for ages above 50 years and is comfortably good below 50 years without much difference between premolars and molars. This study demonstrates the potential value of TCI for age

  18. ON THE NATURE OF THE SOLAR WIND FROM CORONAL PSEUDOSTREAMERS

    International Nuclear Information System (INIS)

    Wang, Y.-M.; Sheeley, N. R. J.R.; Grappin, R.; Robbrecht, E.

    2012-01-01

    Coronal pseudostreamers, which separate like-polarity coronal holes, do not have current sheet extensions, unlike the familiar helmet streamers that separate opposite-polarity holes. Both types of streamers taper into narrow plasma sheets that are maintained by continual interchange reconnection with the adjacent open magnetic field lines. White-light observations show that pseudostreamers do not emit plasma blobs; this important difference from helmet streamers is due to the convergence of like-polarity field lines above the X-point, which prevents the underlying loops from expanding outward and pinching off. The main component of the pseudostreamer wind has the form of steady outflow along the open field lines rooted just inside the boundaries of the adjacent coronal holes. These flux tubes are characterized by very rapid expansion below the X-point, followed by reconvergence at greater heights. Analysis of an idealized pseudostreamer configuration shows that, as the separation between the underlying holes increases, the X-point rises and the expansion factor f ss at the source surface increases. In situ observations of pseudostreamer crossings indicate wind speeds v ranging from ∼350 to ∼550 km s –1 , with O 7+ /O 6+ ratios that are enhanced compared with those in high-speed streams but substantially lower than in the slow solar wind. Hydrodynamic energy-balance models show that the empirical v-f ss relation overestimates the wind speeds from nonmonotonically expanding flux tubes, particularly when the X-point is located at low heights and f ss is small. We conclude that pseudostreamers produce a 'hybrid' type of outflow that is intermediate between classical slow and fast solar wind.

  19. Interpretation of the coronal magnetic field configuration of the Sun

    International Nuclear Information System (INIS)

    Li Bo; Yu Hui; Li Xing

    2012-01-01

    The origin of the heliospheric magnetic flux on the Sun, and hence the origin of the solar wind, is a topic of hot debate. While the prevailing view is that the solar wind originates from outside the coronal streamer helmets, there also exists the suggestion that the open magnetic field spans a far wider region. Without the definitive measurement of the coronal magnetic field, it is difficult to unambiguously resolve the conflict between the two scenarios. We present two 2-dimensional, Alfvénic-turbulence-based models of the solar corona and solar wind, one with and the other without a closed magnetic field region in the inner corona. The purpose of the latter model is to test whether it is possible to realize a picture suggested by polarimetric measurements of the corona using the Fe XIII 10747 Å line, where open magnetic field lines seem to penetrate the streamer base. The boundary conditions at the coronal base are able to account for important observational constraints, especially those on the magnetic flux distribution. Interestingly, the two models provide similar polarized brightness (pB) distributions in the field of view (FOV) of SOHO/LASCO C2 and C3 coronagraphs. In particular, a dome-shaped feature is present in the C2 FOV even for the model without a closed magnetic field. Moreover, both models fit the Ulysses data scaled to 1 AU equally well. We suggest that: 1) The pB observations cannot be safely taken as a proxy for the magnetic field topology, as is often implicitly assumed. 2) The Ulysses measurements, especially the one showing a nearly uniform distribution with heliocentric latitude of the radial magnetic field, do not rule out the ubiquity of open magnetic fields on the Sun. (research papers)

  20. The SOHO project - Coronal and solar wind investigations

    Science.gov (United States)

    Poland, A. I.; Domingo, V.

    1988-01-01

    The Solar and Heliospheric Observatory (SOHO) satellite mission is planned to study the solar interior, to investigate the physical phenomena related to the formation of the solar corona and the solar wind, and to make in situ measurements of the solar wind. The SOHO instruments designed to study the solar atmosphere and the solar wind are described. The experiments include the study of solar UV radiation, a coronal diagnostic spectrometer, an extreme UV imaging telescope, a UV coronagraph spectrometer, a white light and spectrometric coronagraph, and a study of solar wind anisotropies.

  1. Physical Characteristics of Coronal Region Driving Out the Interplanetary Shock

    Directory of Open Access Journals (Sweden)

    Su Yeon Oh

    2008-03-01

    Full Text Available Using the solar wind data of 2000 observed by ACE, We classified the interplanetary shock on basis of shock driver. We examined the physical properties of shock drivers such as the ratio of charge states(O7/O6 and thermal index(I_{th}. Most of 51 interplanetary shocks are driven by interplanetary coronal mass ejections(ICME; magnetic cloud and ejecta and high speed streams. According to the test of temperature(O7/O6 and I_{th}, we found that ICMEs originated from region with hot source in corona.

  2. Medullary sponge kidney on axial computed tomography

    International Nuclear Information System (INIS)

    Ginalski, J.-M.; Schnyder, Pierre; Portmann, Luc; Jaeger, Philippe

    1991-01-01

    To evaluate features of medullary sponge kidney (MSK) on computed tomography (CT), 4-mm-thick axial slices without intravenous contrast material were 1st made in 13 patients through 24 kidneys which showed images of MSK on excretory urograms. On CT, papillary calcifications were found in 11 kidneys. In 5 of these, the calcifications were not detectable on plain films. Some hyperdense papillae (attenuation value 55-70 Hounsfield units) without calcification were found in 4 other kidneys. 9 kidneys appeared normal. 10 of the 14 kidneys were reexamined by a 2nd series of 4-mm-thick axial slices, 5 min after intravenous injection of 50 ml of Urografin. Images suggesting possible ectasia of precaliceal tubules were found in only 4 kidneys. These images appear much less obvious and characteristic on CT than on excretory urogram and do nothing more than suggest the possibility of MSK. In conclusion, the sensitivity of CT in the detection of MSK is markedly lower than that of excretory urography. In the most florid cases of the disease, CT can only show images suggesting the possibility of MSK. On the other hand, CT appears much more sensitive than plain films and tomograms of excretory in the detection of papillary calcifications, the most frequent complication of MSK. (author). 13 refs.; 3 figs

  3. Axial tomography in live cell laser microscopy

    Science.gov (United States)

    Richter, Verena; Bruns, Sarah; Bruns, Thomas; Weber, Petra; Wagner, Michael; Cremer, Christoph; Schneckenburger, Herbert

    2017-09-01

    Single cell microscopy in a three-dimensional (3-D) environment is reported. Cells are grown in an agarose culture gel, located within microcapillaries and observed from different sides after adaptation of an innovative device for sample rotation. Thus, z-stacks can be recorded by confocal microscopy in different directions and used for illustration in 3-D. This gives additional information, since cells or organelles that appear superimposed in one direction, may be well resolved in another one. The method is tested and validated with single cells expressing a membrane or a mitochondrially associated green fluorescent protein, or cells accumulating fluorescent quantum dots. In addition, axial tomography supports measurements of cellular uptake and distribution of the anticancer drug doxorubicin in the nucleus (2 to 6 h after incubation) or the cytoplasm (24 h). This paper discusses that upon cell rotation an enhanced optical resolution in lateral direction compared to axial direction can be utilized to obtain an improved effective 3-D resolution, which represents an important step toward super-resolution microscopy of living cells.

  4. Axial vessel widening in arborescent monocots.

    Science.gov (United States)

    Petit, Giai; DeClerck, Fabrice A J; Carrer, Marco; Anfodillo, Tommaso

    2014-02-01

    Dicotyledons have evolved a strategy to compensate for the increase in hydraulic resistance to water transport with height growth by widening xylem conduits downwards. In monocots, the accumulation of hydraulic resistance with height should be similar, but the absence of secondary growth represents a strong limitation for the maintenance of xylem hydraulic efficiency during ontogeny. The hydraulic architecture of monocots has been studied but it is unclear how monocots arrange their axial vascular structure during ontogeny to compensate for increases in height. We measured the vessel lumina and estimated the hydraulic diameter (Dh) at different heights along the stem of two arborescent monocots, Bactris gasipaes (Kunth) and Guadua angustifolia (Kunth). For the former, we also estimated the variation in Dh along the leaf rachis. Hydraulic diameter increased basally from the stem apex to the base with a scaling exponent (b) in the range of those reported for dicot trees (b = 0.22 in B. gasipaes; b = 0.31 and 0.23 in G. angustifolia). In B. gasipaes, vessels decrease in Dh from the stem's centre towards the periphery, an opposite pattern compared with dicot trees. Along the leaf rachis, a pattern of increasing Dh basally was also found (b = 0.13). The hydraulic design of the monocots studied revealed an axial pattern of xylem conduits similar to those evolved by dicots to compensate and minimize the negative effect of root-to-leaf length on hydrodynamic resistance to water flow.

  5. Modeling the axial offset anomaly in PWRs

    Energy Technology Data Exchange (ETDEWEB)

    Blok, J.; Chauffriat, S.; Frattini, P. [EPRI, Palo Alto, CA (United States)

    2002-07-01

    Axially un-symmetrical flux depression is defined as axial offset anomaly (AOA) in PWRs. The effect has only been observed in PWR reactor cores operated at high power duty. The threat of AOA limits the aggressiveness of core design, and in extreme form, the effect can decrease shutdown margin near end of cycle (EOC) sufficiently to mandate power reduction. AOA is ultimately the result of boron hideout on fuel. Studies have confirmed that sufficient boron hideout to produce measurable AOA requires relatively large amounts of corrosion products to deposit on the fuel. Because corrosion product deposition is favored in the boiling upper regions of the (high duty) core, the amount of boron uptake in these regions is large in proportion, and core reactivity is affected disproportionately in the upper region of the core. This paper explores possible mechanisms for deposition of corrosion products on fuel and the consequent incorporation of boron compounds. The proposed mechanisms are viewed in the context of corrosion product samples from the Callaway Cycle 9, one of the PWR fuel cycles that exhibited the most severe AOA to date. (author)

  6. Individual and contextual characteristics as determinants of sagittal standing posture: a population-based study of adults.

    Science.gov (United States)

    Araújo, Fábio; Lucas, Raquel; Alegrete, Nuno; Azevedo, Ana; Barros, Henrique

    2014-10-01

    Sagittal standing posture is associated with musculoskeletal symptoms and quality of life. However, the frequency and determinants of suboptimal sagittal alignment outside the clinical context remain to be clarified. To estimate the association of sociodemographic, anthropometric, and behavioral characteristics with sagittal standing posture among adults from the general population. Cross-sectional evaluation of a population-based sample. As part of the EPIPorto study, 489 adults were assessed during 2005 to 2008. Individual spinopelvic parameters were measured. Additionally, participants were classified into one of four types of sagittal postural patterns (Roussouly classification: Types 1, 2, and 4 corresponding to nonneutral postures and Type 3 to a neutral posture). Spinopelvic parameters were recorded from 36-inch sagittal radiographs obtained in free-standing posture. Age, sex, education, occupation, body mass index (BMI), waist circumference, total physical activity, leisure time physical activity, time spent in sitting position, smoking status, and tobacco cumulative exposure were collected. Individual parameters and patterns of sagittal posture were compared across categories of participants' characteristics. Older age, lower educational level, blue collar occupation, and overall and central obesity were associated with increased sagittal vertical axis and pelvic tilt/pelvic incidence ratio. Taking the neutral postural pattern (Type 3) as reference for the outcome in a multinomial regression model, independently of age, sex, education, total physical activity, and smoking status, overweight adults had higher odds of Type 2 (odds ratio [OR]=1.92; 95% confidence interval [CI]: 1.13-3.27) and Type 4 (OR=2.13; 95% CI: 1.16-3.91) postural patterns in comparison with normal weight subjects. Overall and central obesity were positively related with Type 1 postural pattern (OR=6.10, 95% CI: 1.52-24.57 and OR=3.54, 95% CI: 1.13-11.11, respectively). There was also a

  7. Correlation between lumbar intervertebral disc height and lumbar spine sagittal alignment among asymptomatic Asian young adults.

    Science.gov (United States)

    Zhang, Feng; Zhang, Kai; Tian, Hai-Jun; Wu, Ai-Min; Cheng, Xiao-Fei; Zhou, Tang-Jun; Zhao, Jie

    2018-02-12

    To investigate the distribution and characteristics of the lumbar intervertebral disc height (IDH) in asymptomatic Asian population and to determine whether the lumbar IDH is related to the lumbar spine sagittal alignment. A cohort of 169 cases of asymptomatic volunteers was enrolled from January 2014 to July 2016. All participants underwent magnetic resonance imaging of the lumbar spine and panoramic radiography of the spine. Panoramic radiographs of the spine were taken to evaluate pelvic incidence (PI), sacral slope (SS), and pelvic tilt (PT) using Surgimap® software. Roussouly classification was utilized to categorize all subjects according to the four subtypes of sagittal alignment. The IDH was measured on the MRI mid-saggital section of the vertebral body. The relationships between lumbar IDH and spine-pelvic parameters were also assessed using the Spearman correlation analysis. The reference value ranges of IDH in asymptomatic Asian volunteers between L1/2, L2/3, L3/4, L4/5, and L5/S1 were (6.25, 10.99), (6.97, 12.08), (7.42, 13.3), (7.76, 14.57),and (7.11, 13.12) mm, respectively. Based on the above reference value, the high lumbar intervertebral space is defined as more than 14 mm. According to the Roussouly Classification, there are 33 cases in type I, 48 in type II, 66 in type III, and 22 in type IV. According to the definition of the high IDH, there are two cases in type I, three in type II, nine in type III, and eight in type IV. The results indicated that people in the Roussouly III and IV subtypes had greater values for IDH compared to those of Roussouly I and II subtypes, and the spinopelvic parameters were partly correlated with IDH in different subtypes. In addition, levels L4-L5 showed the highest IDH for all four groups followed by the L3-L4 and L5-S1 levels, and the value of L3-L4 is equivalent to that of L5-S1. All type groups showed moderate and positive correlations between the PI and IDH except the level of L1-L2 in type IV. The IDH may

  8. Long-term stability of anterior open-bite closure with bilateral sagittal split osteotomy.

    Science.gov (United States)

    Fontes, Adelina M; Joondeph, Donald R; Bloomquist, Dale S; Greenlee, Geoffrey M; Wallen, Terry R; Huang, Greg J

    2012-12-01

    Maxillary impaction and bimaxillary osteotomies are used to treat anterior open-bite malocclusions but can have adverse soft-tissue effects. Correcting an anterior open bite with a single mandibular procedure avoids these undesirable soft-tissue effects, but the stability of this procedure is unknown. The purpose of this study was to assess the long-term stability of anterior open-bite correction with bilateral sagittal split osteotomy and rigid internal fixation. Orthognathic surgical records of 1 oral surgeon were searched for all patients treated for anterior open bite with bilateral sagittal split osteotomy and surgical closing rotation of the mandible with rigid internal fixation. Cephalometric films from initial consultation, presurgery, postsurgery, orthodontic appliance removal, and a mean of 4.5 years after orthodontic appliance removal were collected, traced, and measured. Thirty-one patients fit the inclusion criteria for this study and had an initial mean open bite of -2.6 mm (SD, 1.1 mm). The patients experienced an average mandibular closing rotation of 3.7° (SD, 2.4°) with surgery. By orthodontic appliance removal, the mandible rotated open 1.1°, and incisor overlap was 1.4 mm (SD, 1.0 mm). Approximately 4.5 years after orthodontic appliance removal, the mean incisor overlap was maintained at 1.0 mm (SD, 1.0 mm), yet the mandible rotated open an additional 1.1°. Only 3 patients relapsed to no incisor overlap in the long term, and only 3 patients experienced relapse greater than 1 mm in the long term. Approximately 90% of the treated patients had a positive incisor overlap 4.5 years after orthodontic appliance removal. Despite a 60% loss of mandibular surgical closing rotation, only 10% of the patients relapsed to no incisor overlap in the long term. Bilateral sagittal split osteotomy and surgical closing rotation of the mandible by using rigid internal fixation should be considered a stable alternative in the treatment of mild

  9. Reliability of the Radiographic Sagittal and Frontal Tibiotalar Alignment after Ankle Arthrodesis.

    Directory of Open Access Journals (Sweden)

    Madeleine Willegger

    Full Text Available Accurate measurement of the tibiotalar alignment is important in radiographic outcome assessment of ankle arthrodesis (AA. In studies, various radiological methods have been used to measure the tibiotalar alignment leading to facultative misinterpretation of results. However, to our knowledge, no previous study has investigated the reliability of tibiotalar alignment measurement in AA. We aimed to investigate the reliability of four different methods of measurement of the frontal and sagittal tibiotalar alignment after AA, and to further clarify the most reliable method for determining the longitudinal axis of the tibia.Thirty-eight weight bearing anterior to posterior and lateral ankle radiographs of thirty-seven patients who had undergone AA with a two screw fixation technique were selected. Three observers measured the frontal tibiotalar angle (FTTA and the sagittal tibiotalar angle (STTA using four different methods. The methods differed by the definition of the longitudinal tibial axis. Method A was defined by a line drawn along the lateral tibial border in anterior to posterior radiographs and along the posterior tibial border in lateral radiographs. Method B was defined by a line connecting two points in the middle of the proximal and the distal tibial shaft. Method C was drawn "freestyle"along the longitudinal axis of the tibia, and method D was defined by a line connecting the center of the tibial articular surface and a point in the middle of the proximal tibial shaft. Intra- and interobserver correlation coefficients (ICC and repeated measurement ANOVA were calculated to assess measurement reliability and accuracy.All four methods showed excellent inter- and intraobserver reliability for the FTTA and the STTA. When the longitudinal tibial axis is defined by connecting two points in the middle of the proximal and the distal tibial shaft, the highest interobserver reliability for the FTTA (ICC: 0.980; CI 95%: 0.966-0.989 and for the

  10. Reliability of the Radiographic Sagittal and Frontal Tibiotalar Alignment after Ankle Arthrodesis.

    Science.gov (United States)

    Willegger, Madeleine; Holinka, Johannes; Nemecek, Elena; Bock, Peter; Wanivenhaus, Axel Hugo; Windhager, Reinhard; Schuh, Reinhard

    2016-01-01

    Accurate measurement of the tibiotalar alignment is important in radiographic outcome assessment of ankle arthrodesis (AA). In studies, various radiological methods have been used to measure the tibiotalar alignment leading to facultative misinterpretation of results. However, to our knowledge, no previous study has investigated the reliability of tibiotalar alignment measurement in AA. We aimed to investigate the reliability of four different methods of measurement of the frontal and sagittal tibiotalar alignment after AA, and to further clarify the most reliable method for determining the longitudinal axis of the tibia. Thirty-eight weight bearing anterior to posterior and lateral ankle radiographs of thirty-seven patients who had undergone AA with a two screw fixation technique were selected. Three observers measured the frontal tibiotalar angle (FTTA) and the sagittal tibiotalar angle (STTA) using four different methods. The methods differed by the definition of the longitudinal tibial axis. Method A was defined by a line drawn along the lateral tibial border in anterior to posterior radiographs and along the posterior tibial border in lateral radiographs. Method B was defined by a line connecting two points in the middle of the proximal and the distal tibial shaft. Method C was drawn "freestyle"along the longitudinal axis of the tibia, and method D was defined by a line connecting the center of the tibial articular surface and a point in the middle of the proximal tibial shaft. Intra- and interobserver correlation coefficients (ICC) and repeated measurement ANOVA were calculated to assess measurement reliability and accuracy. All four methods showed excellent inter- and intraobserver reliability for the FTTA and the STTA. When the longitudinal tibial axis is defined by connecting two points in the middle of the proximal and the distal tibial shaft, the highest interobserver reliability for the FTTA (ICC: 0.980; CI 95%: 0.966-0.989) and for the STTA (ICC: 0

  11. Correlation between Sagittal Spinopelvic Parametersand Oswestry Disability Indexafter Thoracal and Lumbar Spine Stabilization and Fusion

    Directory of Open Access Journals (Sweden)

    Yudistira Prama Tirta

    2017-04-01

    Full Text Available Spinopelvic parameter consists of sagittal vertical axis (SVA, pelvic incidence (PI, pelvic tilt (PT, sacral slope (SS which are measured by whole-spine-lateral-view radiograph in standing position. Measurement of the separameters is pivotalas the land mark analysis toachieve correct sagittal balance. The objective of the study is to analyze the correlation between PI, PT, SVA and SSwith theclinical outcomes which was measured usingOswestry Disability Index (ODI scoring system.This is a cross-sectional study involving 19 patients who underwent thoracal and lumbar fusion surgery in our centerduring 2012-2014. Radiographi cevaluation of SVA, PI, PT, and SS and ODI score were performed 1 year after surgery. Pearson test was conducted to determine the correlation between SVA, PI, PT, and SS with ODI score.There wasa strong correlation between ODI withSVA and PI (p<0.001,r=0.866; p=0.006; r=0.603, respectively. There was no correlation between other parameters with ODI.Based on this study, spinopelvic parameters that can represent the clinical outcome after thoracal and lumbar fusion and stabilization surgeries are SVA and PI. Keywords: spinopelvic parameter, post operation, vertebrae fusion.   Korelasi antara Parameter Luaran Spinopelvik Sagital dengan Oswestry Disability Index pasca Stabilisasi dan Fusi Vertebra Torakal dan Lumbar   Abstrak Parameter spinopelvis terdiri atas sagittal vertical axis (SVA, pelvic incidence (PI, pelvic tilt (PT, sacral slope (SS dan diukur menggunakan X-ray seluruh tulang belakang lateral yang diambil pada posisi berdiri. Pengukuran parameter ini penting sebagai dasar analisis keseimbangan sagital pada operasi rekonstruksi vertebra. Tujuan penelitian ini adalah untuk menganalisis korelasi antara PI, PT, SVA, dan SS pada luaran klinis berdasarkan sistem skoring oswestry disability index (ODI. Studi ini adalah studi potong lintang dengan 19 subjek yang menjalani fusi dan stabilisasi torakal dan lumbal di center kami

  12. Chronic low back pain after lumbosacral fracture due to sagittal and frontal vertebral imbalance.

    Science.gov (United States)

    Boyoud-Garnier, L; Boudissa, M; Ruatti, S; Kerschbaumer, G; Grobost, P; Tonetti, J

    2017-06-01

    Over time, some patients with unilateral or bilateral lumbosacral injuries experience chronic low back pain. We studied the sagittal and frontal balance in a population with these injuries to determine whether mismatch in the pelvic and lumbar angles are associated with chronic low back pain. Patients with posterior pelvic ring fractures (Tile C1, C2, C3 and A3.3) that had healed were included. Foreign patients and those with an associated spinal or acetabular fracture or nonunion were excluded. The review consisted of subjective questionnaires, a clinical examination, and standing A/P and lateral stereoradiographic views. The pelvic tilt (PT), sacral slope (SS), pelvic incidence (PI), measured lumbar lordosis (LLm), T9 sagittal offset, leg discrepancy (LD) and lateral curvature (LC). The expected lumbar lordosis (LLe) was calculated using the formula LLe=PI+9°. We defined lumbopelvic mismatch (LPM) as the difference between LLm and LLe being equal or greater than 25% of LLe. Fifteen patients were reviewed after an average follow-up of 8.8 years [5.4-15]. There were four Tile C1, five Tile C2, five Tile C3 and one Tile A3.3 fracture. Ten of the 15 patients had low back pain. The mean angles were: LLm 49.6° and LLe 71.9° (P=0.002), PT 21.3°, SS 44.1°, PI 62.9° in patients with low back pain and LLm 57.4° and LLe 63.2° (P=0.55), PT 13°, SS 43.1°, PI 54.2° in those without. LPM was present in 9 patients, 8 of who had low back pain (P=0.02). Six patients, all of whom had low back pain, had a mean LC of 7.5° [4.5-23] (P=0.02). The mean LD was 0.77cm. The findings of this small study suggest that patients who experience low back pain after their posterior arch of the pelvic ring fracture has healed, have a lumbopelvic mismatch. Early treatment of these patients should aim to reestablish the anatomy of the pelvic base relative to the frontal and sagittal balance. IV. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  13. Non-radiographic methods of measuring global sagittal balance: a systematic review.

    Science.gov (United States)

    Cohen, Larry; Kobayashi, Sarah; Simic, Milena; Dennis, Sarah; Refshauge, Kathryn; Pappas, Evangelos

    2017-01-01

    Global sagittal balance, describing the vertical alignment of the spine, is an important factor in the non-operative and operative management of back pain. However, the typical gold standard method of assessment, radiography, requires exposure to radiation and increased cost, making it unsuitable for repeated use. Non-radiologic methods of assessment are available, but their reliability and validity in the current literature have not been systematically assessed. Therefore, the aim of this systematic review was to synthesise and evaluate the reliability and validity of non-radiographic methods of assessing global sagittal balance. Five electronic databases were searched and methodology evaluated by two independent reviewers using the13-item, reliability and validity, Brink and Louw critical appraisal tool. Fourteen articles describing six methodologies were identified from 3940 records. The six non-radiographic methodologies were biophotogrammetry, plumbline, surface topography, infra-red motion analysis, spinal mouse and ultrasound. Construct validity was evaluated for surface topography ( R  = 0.49 and R  = 0.68, p  infra-red motion-analysis (ICC = 0.81) and plumbline testing (ICC = 0.83). Reliability ranged from moderate (ICC = 0.67) for spinal mouse to very high for surface topography (Cronbach α = 0.985). Measures of agreement ranged from 0.9 mm (plumbline) to 22.94 mm (infra-red motion-analysis). Variability in study populations, reporting parameters and statistics prevented a meta-analysis. The reliability and validity of the non-radiographic methods of measuring global sagittal balance was reported within 14 identified articles. Based on this limited evidence, non-radiographic methods appear to have moderate to very high reliability and limited to three methodologies, moderate to high validity. The overall quality and methodological approaches of the included articles were highly variable. Further research should focus on the

  14. Agreement between fiber optic and optoelectronic systems for quantifying sagittal plane spinal curvature in sitting.

    Science.gov (United States)

    Cloud, Beth A; Zhao, Kristin D; Breighner, Ryan; Giambini, Hugo; An, Kai-Nan

    2014-07-01

    Spinal posture affects how individuals function from a manual wheelchair. There is a need to directly quantify spinal posture in this population to ultimately improve function. A fiber optic system, comprised of an attached series of sensors, is promising for measuring large regions of the spine in individuals sitting in a wheelchair. The purpose of this study was to determine the agreement between fiber optic and optoelectronic systems for measuring spinal curvature, and describe the range of sagittal plane spinal curvatures in natural sitting. Able-bodied adults (n = 26, 13 male) participated. Each participant assumed three sitting postures: natural, slouched (accentuated kyphosis), and extension (accentuated lordosis) sitting. Fiber optic (ShapeTape) and optoelectronic (Optotrak) systems were applied to the skin over spinous processes from S1 to C7 and used to measure sagittal plane spinal curvature. Regions of kyphosis and lordosis were identified. A Cobb angle-like method was used to quantify lordosis and kyphosis. Generalized linear model and Bland-Altman analyses were used to assess agreement. A strong correlation exists between curvature values obtained with Optotrak and ShapeTape (R(2) = 0.98). The mean difference between Optotrak and ShapeTape for kyphosis in natural, extension, and slouched postures was 4.30° (95% LOA: -3.43 to 12.04°), 3.64° (95% LOA: -1.07 to 8.36°), and 4.02° (95% LOA: -2.80 to 10.84°), respectively. The mean difference for lordosis, when present, in natural and extension postures was 2.86° (95% LOA: -1.18 to 6.90°) and 2.55° (95% LOA: -3.38 to 8.48°), respectively. In natural sitting, the mean ± SD of kyphosis values was 35.07 ± 6.75°. Lordosis was detected in 8/26 participants: 11.72 ± 7.32°. The fiber optic and optoelectronic systems demonstrate acceptable agreement for measuring sagittal plane thoracolumbar spinal curvature. Copyright © 2014 Elsevier B.V. All rights reserved.

  15. Axial dispersion in a Kureha Crystal Purifier (KCP)

    Science.gov (United States)

    Otawara, K.; Matsuoka, T.

    2002-04-01

    It is widely accepted that the degree of axial back-mixing in the equipment affects the performance of a column crystallizer. Specifically, small such mixing is inevitable for obtaining highly pure crystal. In fact, it is believed that scale-up of some column crystallizers has been terminated due to the large axial back-mixing or maldistribution. Thus, experiments have been performed for estimating axial dispersion coefficients of liquid phase representing axial back-mixing in the column of a Kureha Crystal Purifier (KCP). The effect of the column diameter on such coefficients has been investigated and it has become evident that the axial back-mixing in the column is more significant in the larger column. Nevertheless, the results have also indicated that the axial back-mixing in KCPs of industrial sizes can be substantially smaller than those in other types of column crystallizers.

  16. Axial stress corrosion cracking forming method to metal tube

    International Nuclear Information System (INIS)

    Araki, Kumiko

    1998-01-01

    Generally, it is more difficult in a metal tube, to intentionally cause a stress corrosion cracking in axial direction than in circumferential direction. In the present invention, a bevel is formed on a metal tube and welding is conducted in circumferential direction along the bevel, and welding is conducted in axial direction partially to the portion welded in circumferential direction. Namely, a bevel is formed in circumferential direction to an abutting portion of thick-walled metal tubes with each other, welding is conducted in circumferential direction along the bevel, and welding is conducted in axial direction partially to a portion welded in circumferential direction. With such procedures, since tensile stress in the circumferential direction is increased partially at a portion welded in axial direction, stress corrosion cracking is caused in axial direction at the portion. Then, stress corrosion cracking in axial direction can thus be formed on the thick-walled metal tube. (N.H.)

  17. Automated Coronal Loop Identification Using Digital Image Processing Techniques

    Science.gov (United States)

    Lee, Jong K.; Gary, G. Allen; Newman, Timothy S.

    2003-01-01

    The results of a master thesis project on a study of computer algorithms for automatic identification of optical-thin, 3-dimensional solar coronal loop centers from extreme ultraviolet and X-ray 2-dimensional images will be presented. These center splines are proxies of associated magnetic field lines. The project is pattern recognition problems in which there are no unique shapes or edges and in which photon and detector noise heavily influence the images. The study explores extraction techniques using: (1) linear feature recognition of local patterns (related to the inertia-tensor concept), (2) parametric space via the Hough transform, and (3) topological adaptive contours (snakes) that constrains curvature and continuity as possible candidates for digital loop detection schemes. We have developed synthesized images for the coronal loops to test the various loop identification algorithms. Since the topology of these solar features is dominated by the magnetic field structure, a first-order magnetic field approximation using multiple dipoles provides a priori information in the identification process. Results from both synthesized and solar images will be presented.

  18. Filament shape versus coronal potential magnetic field structure

    Science.gov (United States)

    Filippov, B.

    2016-01-01

    Solar filament shape in projection on disc depends on the structure of the coronal magnetic field. We calculate the position of polarity inversion lines (PILs) of coronal potential magnetic field at different heights above the photosphere, which compose the magnetic neutral surface, and compare with them the distribution of the filament material in Hα chromospheric images. We found that the most of the filament material is enclosed between two PILs, one at a lower height close to the chromosphere and one at a higher level, which can be considered as a height of the filament spine. Observations of the same filament on the limb by the Solar Terrestrial Relations Observatory spacecraft confirm that the height of the spine is really very close to the value obtained from the PIL and filament border matching. Such matching can be used for filament height estimations in on-disc observations. Filament barbs are housed within protruding sections of the low-level PIL. On the base of simple model, we show that the similarity of the neutral surfaces in potential and non-potential fields with the same sub-photospheric sources is the reason for the found tendency for the filament material to gather near the potential-field neutral surface.

  19. Posterior coronal plating for tibial fractures: technique and advantages

    Directory of Open Access Journals (Sweden)

    Montu Jain

    2014-04-01

    Full Text Available Objective:Tibial shaft fractures are straightforward to treat but when associated with soft tissue injury particularly at the nail entry/plate insertion site or there is significant comminution proximally or a large butterfly fragment/a second split component in the posterior coronal plane, it is a challenge to the treating surgeon. The aim of the present report is to describe the technique of posterior coronal plating in such a scenario and its advantages. Methods:Between July 2008 and June 2011, 12 patients were pro spectively treated by this approach using 4.5 mm broad dynamic compression plates. Results:The time of bony consolidation and full weight bearing averaged 21.7 weeks (range, 16-26 weeks. Patients were followed up for at least 24 months (range, 24-48 months. At 1 year postoper atively, no loss in reduction or alignment was observed. Mean Hospital for Lower Extremity Measurement Functional Score was 72.8 (range, 64-78. All patients were satisfied with their treatment outcomes. Conclusion:Direct posterior approach and fixation using prone position helps to visualise the fracture fragments and provide rigid fixation. The approach is simple and extensile easily, apart from advantages of less soft tissue and hardware problems compared to standard medial or lateral plating. Key words: Tibial fractures; Bone plates; Orthopedic procedures

  20. White-light and radio sounding observations of coronal transients

    Science.gov (United States)

    Bird, M. K.; Volland, H.; Howard, R. A.; Koomen, M. J.; Michels, D. J.; Sheeley, N. R., Jr.; Amstrong, J. W.; Seidel, B. L.; Stelzried, C. T.; Woo, R.

    1985-01-01

    A concerted search for coronal transients was conducted with the 'Solwind' coronagraph during the solar occultations of the two Helios spacecraft in October/November 1979. The polarization angle and bandwidth of the linearly polarized S-band downlink signal were monitored at the three 64-m tracking stations of the NASA Deep Space Network to determine coronal Faraday rotation and spectral broadening. A one-to-one correspondence could be established between abrupt disturbances in the two signal parameters and the passage of a white-light transient through the signal ray path from spacecraft to earth. The white-light morphology and the additional information provided by the radio sounding coverage are presented for each of the five distinct events recorded. Although no specific example could be observed in sufficient detail in both white light and Faraday rotation to derive the small-scale magnetic structure, some qualitative descriptions of the orientation and rough estimates of the magnitude of the transient magnetic field could be made.