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1

Comparison of conventional versus minimally invasive extraperitoneal approach for anterior lumbar interbody fusion  

Microsoft Academic Search

The purpose of the study was to compare conventional versus minimally invasive extraperitoneal approach for anterior lumbar interbody fusion (ALIF). Fifty-six consecutive patients with spondylolisthesis, lumbar instability, or failed back syndrome were treated with ALIF between 1991 and 2001. The patients were retrospectively evaluated and divided in two groups: Group 1, consisting 33 patients, was treated with ALIF using the

V. Saraph; C. Lerch; N. Walochnik; C. M. Bach; M. Krismer; C. Wimmer

2004-01-01

2

Comparison of instrumented anterior interbody fusion with instrumented circumferential lumbar fusion  

Microsoft Academic Search

Posterior lumbar interbody fusion (PLIF) restores disc height, the load bearing ability of anterior ligaments and muscles, root canal dimensions, and spinal balance. It immobilizes the painful degenerate spinal segment and decompresses the nerve roots. Anterior lumbar interbody fusion (ALIF) does the same, but could have complications of graft extrusion, compression and instability contributing to pseudarthrosis in the absence of

S. S. Madan; N. R. Boeree

2003-01-01

3

Anterior Lumbar Interbody Fusion: Two-Year Results with a Modular Interbody Device  

PubMed Central

Study Design Retrospective case series. Purpose To present radiographic outcomes following anterior lumbar interbody fusion (ALIF) utilizing a modular interbody device. Overview of Literature Though multiple anterior lumbar interbody techniques have proven successful in promoting bony fusion, postoperative subsidence remains a frequently reported phenomenon. Methods Forty-three consecutive patients underwent ALIF with (n=30) or without (n=11) supplemental instrumentation. Two patients underwent ALIF to treat failed posterior instrumented fusion. The primary outcome measure was presence of fusion as assessed by computed tomography. Secondary outcome measures were lordosis, intervertebral lordotic angle (ILA), disc height, subsidence, Bridwell fusion grade, technical complications and pain score. Interobserver reliability of radiographic outcome measures was calculated. Results Forty-three patients underwent ALIF of 73 motion segments. ILA and disc height increased over baseline, and this persisted through final follow-up (p<0.01). Solid anterior interbody fusion was present in 71 of 73 motion segments (97%). The amount of new bone formation in the interbody space increased over serial imaging. Subsidence >4 mm occurred in 12% of patients. There were eight surgical complications (19%): one major (reoperation for nonunion/progressive subsidence) and seven minor (five subsidence, two malposition). Conclusions The use of a modular interbody device for ALIF resulted in a high rate of radiographic fusion and a low rate of subsidence. The large endplate and modular design of the device may contribute to a low rate of subsidence as well as maintenance of ILA and lordosis. Previously reported quantitative radiographic outcome measures were found to be more reliable than qualitative or categorical measures. PMID:25346811

Yeoman, Chevas; Chung, Woosik M.; Chappuis, James L; Freedman, Brett

2014-01-01

4

Anterior Lumbar Interbody Fusion for the Treatment of Postoperative Spondylodiscitis  

PubMed Central

Objective To analyze the clinical courses and outcomes after anterior lumbar interbody fusion (ALIF) for the treatment of postoperative spondylodiscitis. Methods A total of 13 consecutive patients with postoperative spondylodiscitis treated with ALIF at our institute from January, 1994 to August, 2013 were included (92.3% male, mean age 54.5 years old). The outcome data including inflammatory markers (leukocyte count, C-reactive protein, erythrocyte sedimentation rate), the Oswestry Disability Index (ODI), the modified Visual Analogue Scale (VAS), and bony fusion rate using spine X-ray were obtained before and 6 months after ALIF. Results All of the cases were effectively treated with combination of systemic antibiotics and ALIF with normalization of the inflammatory markers. The mean VAS for back and leg pain before ALIF was 6.8±1.1, which improved to 3.2±2.2 at 6 months after ALIF. The mean ODI score before ALIF was 70.0±14.8, which improved to 34.2±27.0 at 6 months after ALIF. Successful bony fusion rate was 84.6% (11/13) and the remaining two patients were also asymptomatic. Conclusion Our results suggest that ALIF is an effective treatment option for postoperative spondylodiscitis. PMID:25371780

Kim, Sung Han; Kang, Moo-Sung; Chin, Dong-Kyu; Kim, Keun-Su; Cho, Yong-Eun

2014-01-01

5

Biomechanical comparison of anterior lumbar interbody fusion: stand-alone interbody cage versus interbody cage with pedicle screw fixation - a finite element analysis  

PubMed Central

Background Anterior lumbar interbody fusion (ALIF) followed by pedicle screw fixation (PSF) is used to restore the height of the intervertebral disc and provide stability. Recently, stand-alone interbody cage with anterior fixation has been introduced, which eliminates the need for posterior surgery. We compared the biomechanics of the stand-alone interbody cage to that of the interbody cage with additional PSF in ALIF. Methods A three-dimensional, non-linear finite element model (FEM) of the L2-5 segment was modified to simulate ALIF in L3-4. The models were tested under the following conditions: (1) intact spine, (2) destabilized spine, (3) with the interbody cage alone (type 1), (4) with the stand-alone cage with anterior fixation (SynFix-LR®; type 2), and (5) with type 1 in addition to PSF (type 3). Range of motion (ROM) and the stiffness of the operated level, ROM of the adjacent segments, load sharing distribution, facet load, and vertebral body stress were quantified with external loading. Results The implanted models had decreased ROM and increased stiffness compared to those of the destabilized spine. The type 2 had differences in ROM limitation of 8%, 10%, 4%, and 6% in flexion, extension, axial rotation, and lateral bending, respectively, compared to those of type 3. Type 2 had decreased ROM of the upper and lower adjacent segments by 3-11% and 3-6%, respectively, compared to those of type 3. The greatest reduction in facet load at the operated level was observed in type 3 (71%), followed by type 2 (31%) and type 1 (23%). An increase in facet load at the adjacent level was highest in type 3, followed by type 2 and type 1. The distribution of load sharing in type 2 (anterior:posterior, 95:5) was similar to that of the intact spine (89:11), while type 3 migrated posterior (75:25) to the normal. Type 2 reduced about 15% of the stress on the lower vertebral endplate compared to that in type 1. The stress of type 2 increased two-fold compared to the stress of type 3, especially in extension. Conclusions The stand-alone interbody cage can provide sufficient stability, reduce stress in adjacent levels, and share the loading distribution in a manner similar to an intact spine. PMID:23890389

2013-01-01

6

Endoscopic Foraminal Decompression Preceding Oblique Lateral Lumbar Interbody Fusion To Decrease The Incidence Of Post Operative Dysaesthesia  

PubMed Central

Background Lumbar interbody fusion has become a well established method to diminish axial back pain as well as radiculopathy in patients with degenerative disc disease, stenosis, and instability. The concept of indirect decompression of the neural foramen and spinal canal while performing fusion became popular in the mid 1990’s with description of ALIF techniques. Morphometric analysis confirmed the extent of decompression of posterior elements with interbody height restoration. In an attempt to diminish potential complications associated with anterior or posterior approaches to the spine for interbody fusion, and with the hope of accomplishing fusion in a less invasive manner, lateral lumbar interbody fusion has become quite popular. This transpsoas approach to the disc space has been associated with a high incidence of neurologic complications. Even though this is the first technique to routinely recommend EMG monitoring to increase safety in the approach, neurologic injuries still occur. A newer oblique lateral lumbar interbody (OLLIF) approach has recently been described to lessen the incidence of neurologic injury. This technique also advocates use of EMG testing to lessen neurologic trauma. In spite of this precaution, neurologic insult has not been eliminated. In fact, even in patients whose electrical stimulation thresholds suggested a safe entry space into the disc, transient dysaesthesia continues to occur in 20-25 percent of cases. Purpose This pilot study reflects data and observations of a subset of patients treated with endoscopic foraminotomy preceding oblique lateral lumbar interbody fusion (OLLIF) to assess specifically potential improvements in dysaesthesia rates. Methods A select subset of patients undergoing OLLIF failed to meet electrodiagnostic criteria for safe disc access through Kambin’s triangle. These patients underwent an endoscopic foraminotomy and exiting nerve decompression prior to discectomy, endplate preparation and cage insertion. Results Dysaesthesia did not occur in these patients whom otherwise would have likely been at risk for neurologic deficit. Conclusions These findings suggest that patients at risk for neurologic insult during oblique lateral lumbar interbody fusion can be protected by foraminoplasty. PMID:25694923

Katzell, Jeffrey

2014-01-01

7

Analysis of spinal lumbar interbody fusion cage subsidence using Taguchi method, finite element analysis, and artificial neural network  

NASA Astrophysics Data System (ADS)

Subsidence, when implant penetration induces failure of the vertebral body, occurs commonly after spinal reconstruction. Anterior lumbar interbody fusion (ALIF) cages may subside into the vertebral body and lead to kyphotic deformity. No previous studies have utilized an artificial neural network (ANN) for the design of a spinal interbody fusion cage. In this study, the neural network was applied after initiation from a Taguchi L 18 orthogonal design array. Three-dimensional finite element analysis (FEA) was performed to address the resistance to subsidence based on the design changes of the material and cage contact region, including design of the ridges and size of the graft area. The calculated subsidence is derived from the ANN objective function which is defined as the resulting maximum von Mises stress (VMS) on the surface of a simulated bone body after axial compressive loading. The ANN was found to have minimized the bone surface VMS, thereby optimizing the ALIF cage given the design space. Therefore, the Taguchi-FEA-ANN approach can serve as an effective procedure for designing a spinal fusion cage and improving the biomechanical properties.

Nassau, Christopher John; Litofsky, N. Scott; Lin, Yuyi

2012-09-01

8

Minimally invasive transforaminal lumbar interbody fusion  

PubMed Central

Background: The use of minimally invasive surgical (MIS) techniques represents the most recent modification of methods used to achieve lumbar interbody fusion. The advantages of minimally invasive spinal instrumentation techniques are less soft tissue injury, reduced blood loss, less postoperative pain and shorter hospital stay while achieving clinical outcomes comparable with equivalent open procedure. The aim was to study the clinicoradiological outcome of minimally invasive transforaminal lumbar interbody fusion. Materials and Methods: This prospective study was conducted on 23 patients, 17 females and 6 males, who underwent MIS-transforaminal lumbar interbody fusion (TLIF) followed up for a mean 15 months. The subjects were evaluated for clinical and radiological outcome who were manifested by back pain alone (n = 4) or back pain with leg pain (n = 19) associated with a primary diagnosis of degenerative spondylolisthesis, massive disc herniation, lumbar stenosis, recurrent disc herniation or degenerative disc disease. Paraspinal approach was used in all patients. The clinical outcome was assessed using the revised Oswestry disability index and Macnab criteria. Results: The mean age of subjects was 55.45 years. L4-L5 level was operated in 14 subjects, L5-S1 in 7 subjects; L3-L4 and double level was fixed in 1 patient each. L4-L5 degenerative listhesis was the most common indication (n = 12). Average operative time was 3 h. Fourteen patients had excellent results, a good result in 5 subjects, 2 subjects had fair results and 2 had poor results. Three patients had persistent back pain, 4 patients had residual numbness or radiculopathy. All patients had a radiological union except for 1 patient. Conclusion: The study demonstrates a good clinicoradiological outcome of minimally invasive TLIF. It is also superior in terms of postoperative back pain, blood loss, hospital stay, recovery time as well as medication use. PMID:25404767

Jhala, Amit; Singh, Damandeep; Mistry, MS

2014-01-01

9

Comparison of Transforaminal Lumbar Interbody Fusion with Direct Lumbar Interbody Fusion: Clinical and Radiological Results  

PubMed Central

Objective The use of direct lumbar interbody fusion (DLIF) has gradually increased; however, no studies have directly compared DLIF and transforaminal lumbar interbody fusion (TLIF). We compared DLIF and TLIF on the basis of clinical and radiological outcomes. Methods A retrospective review was performed on the medical records and radiographs of 98 and 81 patients who underwent TLIF and DLIF between January 2011 and December 2012. Clinical outcomes were compared with a visual analog scale (VAS) and the Oswestry disability index (ODI). The preoperative and postoperative disc heights, segmental sagittal/coronal angles, and lumbar lordosis were measured on radiographs. Fusion rates, operative time, estimated blood loss (EBL), length of hospital stay, and complications were assessed. Results DLIF was superior to TLIF regarding its ability to restore disc height, foraminal height, and coronal balance (p<0.001). As the extent of surgical level increased, DLIF displayed significant advantages over TLIF considering the operative time and EBL. However, fusion rates at 12 months post-operation were lower for DLIF (87.8%) than for TLIF (98.1%) (p=0.007). The changes of VAS and ODI between the TLIF and DLIF were not significantly different (p>0.05). Conclusion Both DLIF and TLIF are less invasive and thus good surgical options for treating degenerative lumber diseases. DLIF has higher potential in increasing neural foramina and correcting coronal balance, and involves a shorter operative time and reduced EBL, in comparison with TLIF. However, DLIF displayed a lower fusion rate than TLIF, and caused complications related to the transpsoas approach. PMID:25628805

Lee, Young Seok; Park, Seung Won; Chung, Chan

2014-01-01

10

Posterior interbody fusion using laminectomy bone and transpedicular screw fixation in the treatment of lumbar spondylolisthesis  

Microsoft Academic Search

BACKGROUNDLaminectomy bone is used widely in posterolateral lumbar fusion, but not interbody fusion. No prospective evaluation of interbody fusion using bone grafts from the posterior neural arch in spondylolisthesis has been found in the literature. We prospectively studied series of patients operated on for lumbar spondylolisthesis to evaluate clinical improvement and bony fusion.METHODSForty-six patients were operated on for lumbar spondylolisthesis

György I Csécsei; Álmos P Klekner; József Dobai; Attila Lajgut; Judit Sikula

2000-01-01

11

Finite element analysis of minimal invasive transforaminal lumbar interbody fusion.  

PubMed

The purpose of our study is to develop and validate three-dimensional finite element models of transforaminal lumbar interbody fusion, and explore the most appropriate method of fixation and fusion by comparing biomechanical characteristics of different fixation method. We developed four fusion models: bilateral pedicle screws fixation with a single cage insertion model (A), bilateral pedicle screws fixation with two cages insertion model (B), unilateral pedicle screws fixation with a single cage insertion model (C), and unilateral pedicle screws fixation with two cages insertion model (D); the models were subjected to different forces including anterior bending, posterior extension, left bending, right bending, rotation, and axial compressive. The von Mises stress of the fusion segments on the pedicle screw and cages was recorded. Angular variation and stress of pedicle screw and cage were compared. There were differences of Von Mises peak stress among four models, but were within the range of maximum force. The angular variation in A, B, C, and D decreased significantly compared with normal. There was no significant difference of angular variation between A and B, and C and D. Bilateral pedicle screws fixation had more superior biomechanics than unilateral pedicle screws fixation. In conclusion, the lumbar interbody fusion models were established using varying fixation methods, and the results verified that unilateral pedicle screws fixation with a single cage could meet the stability demand in minimal invasive transforaminal interbody fusion. PMID:24782059

Zhao, Chuncheng; Wang, Xinhu; Chen, Changchun; Kang, Yanzhong

2014-09-01

12

Biomechanical Characteristics of an Integrated Lumbar Interbody Fusion Device  

PubMed Central

Introduction We hypothesized that an Integrated Lumbar Interbody Fusion Device (PILLAR SA, Orthofix, Lewisville, TX) will function biomechanically similar to a traditional anterior interbody spacer (PILLAR AL, Orthofix, Lewisville, TX) plus posterior instrumentation (FIREBIRD, Orthofix, Lewisville, TX). Purpose of this study was to determine if an Integrated Interbody Fusion Device (PILLAR SA) can stabilize single motion segments as well as an anterior interbody spacer (PILLAR AL) + pedicle screw construct (FIREBIRD). Methods Eight cadaveric lumbar spines (age: 43.9±4.3 years) were used. Each specimen's range of motion was tested in flexion-extension (FE), lateral bending (LB), and axial rotation (AR) under intact condition, after L4-L5 PILLAR SA with intervertebral screws and after L4-L5 360° fusion (PILLAR AL + Pedicle Screws and rods (FIREBIRD). Each specimen was tested in flexion (8Nm) and extension (6Nm) without preload (0 N) and under 400N of preload, in lateral bending (±6 Nm) and axial rotation (±5 Nm) without preload. Results Integrated fusion using the PILLAR SA device demonstrated statistically significant reductions in range of motion of the L4-L5 motion segment as compared to the intact condition for each test direction. PILLAR SA reduced ROM from 8.9±1.9 to 2.9±1.1° in FE with 400N follower preload (67.4%), 8.0±1.7 to 2.5±1.1° in LB, and 2.2±1.2 to 0.7±0.3° in AR. A comparison between the PILLAR SA integrated fusion device versus 360° fusion construct with spacer and bilateral pedicle screws was statistically significant in FE and LB. The 360° fusion yielded motion of 1.0±0.5° in FE, 1.0±0.8° in LB (p0.05). Conclusions The PILLAR SA resulted in motions of less than 3° in all modes of motion and was not as motion restricting as the traditional 360° using bilateral pedicle screws. The residual segmental motions compare very favorably with published biomechanical studies of other interbody integrated fusion devices.

Voronov, Leonard I.; Vastardis, Georgios; Zelenakova, Julia; Carandang, Gerard; Havey, Robert M.; Waldorff, Erik I.; Zindrick, Michael R.

2014-01-01

13

Posterolateral lumbar spine fusion with INFUSE bone graft  

Microsoft Academic Search

Background contextINFUSE has been proven effective in conjunction with threaded cages and bone dowels for single-level anterior lumbar interbody fusion (ALIF). The published experience with posterolateral fusion, although encouraging, utilizes a significantly higher dose and concentration of recombinant human bone morphogenic protein-2 (rhBMP-2) and a different carrier than the commercially available INFUSE.

Steven D. Glassman; Leah Carreon; Mladen Djurasovic; Mitchell J. Campbell; Rolando M. Puno; John R. Johnson; John R. Dimar

2007-01-01

14

Fusion rate after posterior lumbar interbody fusion with carbon fiber implant: 1-year follow-up of 51 patients  

Microsoft Academic Search

Problems associated with posterior lumbar interbody fusion (PLIF) have traditionally included the need for donor bone, prolonged healing time of donor bone, the difficulty of cutting precise bony channels, the risk of retropulsion of graft, postoperative collapse of the bone graft, and pseudarthrosis. To avoid these problems a carbon fiber reinforced polymer implant cage has been developed to facilitate interbody

T. Tullberg; B. Brandt; J. Rydberg; P. Fritzell

1996-01-01

15

Comparison of the early results of transforaminal lumbar interbody fusion and posterior lumbar interbody fusion in symptomatic lumbar instability  

PubMed Central

Background: Transforaminal lumbar interbody fusion (TLIF) has been preferred to posterior lumbar interbody fusion (PLIF) for different spinal disorders but there had been no study comparing their outcome in lumbar instability. A comparative retrospective analysis of the early results of TLIF and PLIF in symptomatic lumbar instability was conducted between 2005 and 2011. Materials and Methods: Review of the records of 102 operated cases of lumbar instability with minimum 1 year followup was done. A total of 52 cases (11 men and 41 women, mean age 46 years SD 05.88, range 40-59 years) underwent PLIF and 50 cases (14 men and 36 women, mean age 49 years SD 06.88, range 40-59 years) underwent TLIF. The surgical time, duration of hospital stay, intraoperative blood loss were compared. Self-evaluated low back pain and leg pain status (using Visual Analog Score), disability outcome (using Oswestry disability questionnaire) was analyzed. Radiological structural restoration (e.g., disc height, foraminal height, lordotic angle, and slip reduction), stability (using Posner criteria), fusion (using Hackenberg criteria), and overall functional outcome (using MacNab's criteria) were compared. Results: Pain, disability, neurology, and overall functional status were significantly improved in both groups but PLIF required more operative time and caused more blood loss. Postoperative hospital stay, structural restoration, stability, and fusion had no significant difference but neural complications were relatively more with PLIF. Conclusions: Both methods were effective in relieving symptoms, achieving structural restoration, stability, and fusion, but TLIF had been associated with shorter operative time, less blood loss, and lesser complication rates for which it can be preferred for symptomatic lumbar instability. PMID:23798756

Sakeb, Najmus; Ahsan, Kamrul

2013-01-01

16

Clinical and Radiological Outcomes of Segmental Spinal Fusion in Transforaminal Lumbar Interbody Fusion with Spinous Process Tricortical Autograft  

PubMed Central

Study Design A retrospective study. Purpose To investigate clinical and radiological outcomes when using spinous process as a tricortical autograft for segmental spinal fusion in transforaminal lumbar interbody fusion (TLIF). Overview of Literature Interbody spinal fusion is one of the important procedures in spinal surgery. Many types of autografts are harvested at the expense of complications. Clinical and radiographic results of patients who underwent TLIF with intraoperative harvested spinous process autograft in Prasat Neurological Institue, Bangkok, Thailand, were assessed as new technical innovation. Methods Between October 2005 to July 2009, 30 cases of patients who underwent TLIF with spinous process tricortical autograft were included. Clinical evaluations were assessed by visual analog scales (VAS) and Prolo functional and economic scores at the preoperation and postoperation and at 2 years postoperation. Static and dynamic plain radiograph of lumbar spine were reviewed for achievement of fusion. Results Initial successful fusion time in lumbar interbody fusion with spinous process tricortical autograft was 4.72 months (range, 3.8-6.1 months) postoperation and 100% fusion rate was reported at 2 years. Our initial successful fusion time in lumbar interbody fusion was compared to the other types of grafts in previous literatures. Conclusions The use of intraoperative harvested spinous process tricortical autograft has overcome many disadvantages of harvesting autograft with better initial successful fusion time (4.72 months). VAS and Prolo scores showed some improvement in the outcomes between the preoperative and postoperative periods. PMID:24761199

Tangviriyapaiboon, Teera

2014-01-01

17

Direct Lateral Lumbar Interbody Fusion: Clinical and Radiological Outcomes  

PubMed Central

Objective According to the recent development of minimally invasive spinal surgery, direct lumbar interbody fusion (DLIF) was introduced as an effective option to treat lumbar degenerative diseases. However, comprehensive results of DLIF have not been reported in Korea yet. The object of this study is to summarize radiological and clinical outcomes of our DLIF experience. Methods We performed DLIF for 130 patients from May 2011 to June 2013. Among them, 90 patients, who could be followed up for more than 6 months, were analyzed retrospectively. Clinical outcomes were compared using visual analog scale (VAS) score and Oswestry Disability Index (ODI). Bilateral foramen areas, disc height, segmental coronal and sagittal angle, and regional sagittal angle were measured. Additionally, fusion rate was assessed. Results A total of 90 patients, 116 levels, were underwent DLIF. The VAS and ODI improved statistically significant after surgery. All the approaches for DLIF were done on the left side. The left and right side foramen area changed from 99.5 mm2 and 102.9 mm2 to 159.2 mm2 and 151.2 mm2 postoperatively (p<0.001). Pre- and postoperative segmental coronal and sagittal angles changed statistically significant from 4.1° and 9.9° to 1.1° and 11.1°. Fusion rates of 6 and 12 months were 60.9% and 87.8%. Complications occurred in 17 patients (18.9%). However, most of the complications were resolved within 2 months. Conclusion DLIF is not only effective for indirect decompression and deformity correction but also shows satisfactory mechanical stability and fusion rate. PMID:25132930

Lee, Young Seok; Kim, Young Baeg

2014-01-01

18

Allograft Cellular Bone Matrix in Extreme Lateral Interbody Fusion: Preliminary Radiographic and Clinical Outcomes  

PubMed Central

Introduction. Extreme lateral interbody fusion (XLIF) is a minimally disruptive alternative for anterior lumbar interbody fusion. Recently, synthetic and allograft materials have been increasingly used to eliminate donor-site pain and complications secondary to autogenous bone graft harvesting. The clinical use of allograft cellular bone graft has potential advantages over autograft by eliminating the need to harvest autograft while mimicking autograft's biologic function. The objective of this study was to examine 12-month radiographic and clinical outcomes in patients who underwent XLIF with Osteocel Plus, one such allograft cellular bone matrix. Methods. Forty (40) patients were treated at 61 levels with XLIF and Osteocel Plus and included in the analysis. Results. No complications were observed. From preoperative to 12-month postoperative followup, ODI improved 41%, LBP improved 55%, leg pain improved 43.3%, and QOL (SF-36) improved 56%. At 12 months, 92% reported being “very” or “somewhat” satisfied with their outcome and 86% being either “very” or “somewhat likely” to choose to undergo the procedure again. Complete fusion was observed in 90.2% (55/61) of XLIF levels. Conclusions. Complete interbody fusion with Osteocel Plus was shown in 90.2% of XLIF levels, with the remaining 9.8% being partially consolidated and progressing towards fusion at 12 months. PMID:23251099

Tohmeh, Antoine G.; Watson, Blake; Tohmeh, Mirna; Zielinski, Xavier J.

2012-01-01

19

A biomechanical and histological evaluation of a bioresorbable lumbar interbody fusion cage  

Microsoft Academic Search

Novel spinal interbody fusion cages made of bioactive and bioresorbable composites by a unique forging process were developed. Previous in vitro study demonstrated that these cages marked excellent biomechanical values. The purpose of the present in vivo study was to evaluate the viability and advantage of this forged composite of uncalcined hydroxyapatite\\/poly L-Lactide (F-u-HA\\/PLLA) cage radiographically, biomechanically, and histologically, when

Yoshihiro Hojo; Yoshihisa Kotani; Manabu Ito; Kuniyoshi Abumi; Tsuyoshi Kadosawa; Yasuo Shikinami; Akio Minami

2005-01-01

20

Segmental and global lordosis changes with two-level axial lumbar interbody fusion and posterior instrumentation  

PubMed Central

Background Loss of lumbar lordosis has been reported after lumbar interbody fusion surgery and may portend poor clinical and radiographic outcome. The objective of this research was to measure changes in segmental and global lumbar lordosis in patients treated with presacral axial L4-S1 interbody fusion and posterior instrumentation and to determine if these changes influenced patient outcomes. Methods We performed a retrospective, multi-center review of prospectively collected data in 58 consecutive patients with disabling lumbar pain and radiculopathy unresponsive to nonsurgical treatment who underwent L4-S1 interbody fusion with the AxiaLIF two-level system (Baxano Surgical, Raleigh NC). Main outcomes included back pain severity, Oswestry Disability Index (ODI), Odom's outcome criteria, and fusion status using flexion and extension radiographs and computed tomography scans. Segmental (L4-S1) and global (L1-S1) lumbar lordosis measurements were made using standing lateral radiographs. All patients were followed for at least 24 months (mean: 29 months, range 24-56 months). Results There was no bowel injury, vascular injury, deep infection, neurologic complication or implant failure. Mean back pain severity improved from 7.8±1.7 at baseline to 3.3±2.6 at 2 years (p < 0.001). Mean ODI scores improved from 60±15% at baseline to 34±27% at 2 years (p < 0.001). At final follow-up, 83% of patients were rated as good or excellent using Odom's criteria. Interbody fusion was observed in 111 (96%) of 116 treated interspaces. Maintenance of lordosis, defined as a change in Cobb angle ? 5°, was identified in 84% of patients at L4-S1 and 81% of patients at L1-S1. Patients with loss or gain in segmental or global lordosis experienced similar 2-year outcomes versus those with less than a 5° change. Conclusions/Clinical Relevance Two-level axial interbody fusion supplemented with posterior fixation does not alter segmental or global lordosis in most patients. Patients with postoperative change in lordosis greater than 5° have similarly favorable long-term clinical outcomes and fusion rates compared to patients with less than 5° lordosis change.

Melgar, Miguel A; Tobler, William D; Ernst, Robert J; Raley, Thomas J; Anand, Neel; Miller, Larry E; Nasca, Richard J

2014-01-01

21

MRI Measurement of Neuroforaminal Dimension at the Index and Supradjacent Levels after Anterior Lumbar Interbody Fusion: A Prospective Study  

PubMed Central

Background Anterior interbody fusion has previously been demonstrated to increase neuroforaminal height in a cadaveric model using cages. No prior study has prospectively assessed the relative change in magnetic resonance imaging (MRI) demonstrated neuroforaminal dimensions at the index and supradjacent levels, after anterior interbody fusion with a corticocancellous allograft in a series of patients without posterior decompression. The objective of this study was to determine how much foraminal dimension can be increased with indirect foraminal decompression alone via anterior interbody fusion, and to determine the effect of anterior lumbar interbody fusion on the dimensions of the supradjacent neuroforamina. Methods A prospective study comparing pre- and postoperative neuroforaminal dimensions on MRI scan among 26 consecutive patients undergoing anterior lumbar interbody fusion without posterior decompression was performed. We studies 26 consecutive patients (50 index levels) that had undergone anterior interbody fusion followed by posterior pedicle screw fixation without distraction or foraminotomy. We used preoperative and postoperative MRI imaging to assess the foraminal dimensions at each operated level on which the lumbar spine had been operated. The relative indirect foraminal decompression achieved was calculated. The foraminal dimension of the 26 supradjacent untreated levels was measured pre- and postoperatively to serve as a control and to determine any effects after anterior interbody fusion. Results In this study, 8 patients underwent 1 level fusion (L5-S1), 12 patients had 2 levels (L4-S1) and 6 patients had 3 levels (L3-S1). The average increase in foraminal dimension was 43.3% (p < 0.05)-19.2% for L3-4, 57.1% for L4-5, and 40.1% for L5-S1. Mean pre- and postoperative supradjacent neuroforaminal dimension measurements were 125.84 mm2 and 124.89 mm2, respectively. No significant difference was noted (p > 0.05). Conclusions Anterior interbody fusion with a coriticocancellous allograft can significantly increase neuroforaminal dimension even in the absence of formal posterior distraction or foraminotomy; anterior interbody fusion with a coriticocancellous allograft has little effect on supradjacent neuroforaminal dimensions. PMID:23467381

Sokolowski, Mark J.; Mehbod, Amir A.; Denis, Francis; Garvey, Timothy A.; Perl, John; Transfeldt, Ensor E.

2013-01-01

22

Failure of a Carbon Fiber–Reinforced Polymer Implant Used for Transforaminal Lumbar Interbody Fusion  

PubMed Central

Lumbar interbody fusion is a common procedure owing to the high prevalence of degenerative spinal disorders. During such procedures, carbon fiber–reinforced polymer (CFRP) cages are frequently utilized to fill the void created between adjacent vertebral bodies, to provide mechanical stability, and to carry graft material. Failure of such implants can lead to significant morbidity. We discuss the possible causes leading to the failure of a CFRP cage in a patient with rheumatoid arthritis. Review of a 49-year-old woman who underwent revision anterior lumbar interbody fusion 2 years after posterior instrumentation and transforaminal lumbar interbody fusion at L4–L5 and L5–S1. The patient developed pseudarthrosis at the two previously fused levels with failure of the posterior instrumentation. Revision surgery reveled failure with fragmentation of the CFRP cage at the L5–S1 level. CFRP implants can break if mechanical instability or nonunion occurs in the spinal segments, thus emphasizing the need for optimizing medical management and meticulous surgical technique in achieving stability. PMID:24436878

Sardar, Zeeshan; Jarzem, Peter

2013-01-01

23

Complete cage migration/subsidence into the adjacent vertebral body after posterior lumbar interbody fusion.  

PubMed

A variety of implant-related short and long-term complications after lumbar fusion surgery are recognized. Mid to long-term complications due to cage migration and/or cage subsidence are less frequently reported. Here, we report a patient with a complete cage migration into the superior adjacent vertebral body almost 20years after the initial posterior lumbar interbody fusion procedure. In this patient, the cage migration/subsidence was clinically silent, but a selective decompression for adjacent segment degenerative lumbar spinal stenosis was performed. We discuss the risk factors for cage migration/subsidence in view of the current literature. PMID:25455736

Corniola, Marco V; Jägersberg, Max; Stienen, Martin N; Gautschi, Oliver P

2014-11-01

24

A randomized double-blind prospective study of the efficacy of pulsed electromagnetic fields for interbody lumbar fusions  

SciTech Connect

A randomized double-blind prospective study of pulsed electromagnetic fields for lumbar interbody fusions was performed on 195 subjects. There were 98 subjects in the active group and 97 subjects in the placebo group. A brace containing equipment to induce an electromagnetic field was applied to patients undergoing interbody fusion in the active group, and a sham brace was used in the control group. In the active group there was a 92% success rate, while the control group had a 65% success rate (P greater than 0.005). The effectiveness of bone graft stimulation with the device is thus established.

Mooney, V. (Univ. of California, Irvine (USA))

1990-07-01

25

Time-sequential changes of differentially expressed miRNAs during the process of anterior lumbar interbody fusion using equine bone protein extract, rhBMP-2 and autograft  

NASA Astrophysics Data System (ADS)

The precise mechanism of bone regeneration in different bone graft substitutes has been well studied in recent researches. However, miRNAs regulation of the bone formation has been always mysterious. We developed the anterior lumbar interbody fusion (ALIF) model in pigs using equine bone protein extract (BPE), recombinant human bone morphogenetic protein-2 (rhBMP-2) on an absorbable collagen sponge (ACS), and autograft as bone graft substitute, respectively. The miRNA and gene expression profiles of different bone graft materials were examined using microarray technology and data analysis, including self-organizing maps, KEGG pathway and Biological process GO analyses. We then jointly analyzed miRNA and mRNA profiles of the bone fusion tissue at different time points respectively. Results showed that miRNAs, including let-7, miR-129, miR-21, miR-133, miR-140, miR-146, miR-184, and miR-224, were involved in the regulation of the immune and inflammation response, which provided suitable inflammatory microenvironment for bone formation. At late stage, several miRNAs directly regulate SMAD4, Estrogen receptor 1 and 5-hydroxytryptamine (serotonin) receptor 2C for bone formation. It can be concluded that miRNAs play important roles in balancing the inflammation and bone formation.

Chen, Da-Fu; Zhou, Zhi-Yu; Dai, Xue-Jun; Gao, Man-Man; Huang, Bao-Ding; Liang, Tang-Zhao; Shi, Rui; Zou, Li-Jin; Li, Hai-Sheng; Bünger, Cody; Tian, Wei; Zou, Xue-Nong

2014-03-01

26

Influence of Alendronate and Endplate Degeneration to Single Level Posterior Lumbar Spinal Interbody Fusion  

PubMed Central

Objective Using alendronate after spinal fusion is a controversial issue due to the inhibition of osteoclast mediated bone resorption. In addition, there are an increasing number of reports that the endplate degeneration influences the lumbar spinal fusion. The object of this retrospective controlled study was to evaluate how the endplate degeneration and the bisphosphonate medication influence the spinal fusion through radiographic evaluation. Methods In this study, 44 patients who underwent single-level posterior lumbar interbody fusion (PLIF) using cage were examined from April 2007 to March 2009. All patients had been diagnosed as osteoporosis and would be recommended for alendronate medication. Endplate degeneration is categorized by the Modic changes. The solid fusion is defined if there was bridging bone between the vertebral bodies, either within or external to the cage on the plain X-ray and if there is less than 5° of angular difference in dynamic X-ray. Results In alendronate group, fusion was achieved in 66.7% compared to 73.9% in control group (no medication). Alendronate did not influence the fusion rate of PLIF. However, there was the statistical difference of fusion rate between the endplate degeneration group and the group without endplate degeneration. A total of 52.4% of fusion rate was seen in the endplate degeneration group compared to 91.3% in the group without endplate degeneration. The endplate degeneration suppresses the fusion process of PLIF. Conclusion Alendronate does not influence the fusion process in osteoporotic patients. The endplate degeneration decreases the fusion rate. PMID:25620981

Rhee, Wootack; Ha, Seongil; Lim, Jae Hyeon; Jang, Il Tae

2014-01-01

27

[Use of artifiial bone in lateral interbody fusion of the lumbar spine: a prospective radiographic study].  

PubMed

PURPOSE OF THE STUDY The aim of the study was to evaluate the extent of fusion using synthetic ?-tricalcium phosphate as a bone substitute in extreme lateral interbody fusion (XLIF). MATERIAL AnD METHODS In this prospective study, patients undergoing XLIF with an Oracle cage filed with the artifiial bone ChronOs Strip (Synthes, USA) were evaluated. The group consisted of 61 patients, 33 women and 28 men, with an average age of 50.9 years (range, 21 to 73 years). A total of 64 segments were operated on. Stand-alone interbody fusion was performed in 14 segments, lateral plate fiation in 19, transpedicular (TP) fiation before XLIF was carried out in 14 and TP fiation after XLIF in 17 segments. At one-year follow-up, dynamic X-rays to exclude instability, and CT images were obtained in order to evaluate the extent of bone fusion outside the implant (complete fusion, partial fusion, no fusion) and inside it (% of the bone fusion surface area). In addition, bone mineral density following fusion mass bone quality (expressed in Hounsfild units [HU]) was assessed inside the implant at the site of ChronOs Strip placement, using a region of interest (ROI) analysis. For the evaluation of fusion bone quality inside the implant on CT scans with HU qualifiation, the authors propose the following scale: 1. no fusion (0-99 HU) 2. Uncertain fusion (100-190 HU) 3. Probable fusion (200-299 HU) 4. Reliable fusion (300 and more HU) All results were statistically evaluated in relation to the gender, age, treated segment, surgical diagnosis, method of fiation, implant height and intervertebral space reduction at one-year follow-up. RESULTS Fusion outside the implant was complete in 18 segments (28%) and partial in 27 (42%); in 19 segments (30%) it was not detected. The bone fusion surface area inside the implant was 54.5% (0-100%) on the average. It was related to age and implant height; the surface area increased with increasing age and with increasing implant height. Solid bone fusion inside the implant, as assessed on CT images using HU, was reliable in 36 segments (56%), probable in 11 (17%), uncertain in 10 (16%) and was not detected in seven segments (11%). A signifiant relationship was found between the quality of bone fusion and the type of fiation. Of the segments treated by stand-alone XLIF, 29% showed no fusion while the segments managed by lateral plate fiation had 32% of them with probable fusion. Correlations were also found with the height of an implant (the higher the implant, the more reliable its fusion), with age (the higher age, the higher bone density) and with the spinal level (the lower level, the lower bone density). In 45 (70%) segments, bone mineral density inside the implant was higher than the density of surrounding spongious bone. The average density inside the implant was 333.7 HU (14-1075) and that of the surrounding bone was 244.6 HU (66-500). The intervertebral space was reduced by an average of 1.1 mm (0-6.2). All treated segments were found stable on dynamic X-rays. PMID:25651294

Hrabálek, L; ?echáková, E; Bu?val, S; Adamus, M; Langová, K; Vaverka, M

2014-01-01

28

Multilevel extreme lateral interbody fusion (XLIF) and osteotomies for 3-dimensional severe deformity: 25 consecutive cases  

PubMed Central

Background This is a retrospective review of 25 patients with severe lumbar nerve root compression undergoing multilevel anterior retroperitoneal lumbar interbody fusion and posterior instrumentation for deformity. The objective is to analyze the outcomes and clinical results from anterior interbody fusions performed through a lateral approach and compare these with traditional surgical procedures. Methods A consecutive series of 25 patients (78 extreme lateral interbody fusion [XLIF] levels) was identified to illustrate the primary advantages of XLIF in correcting the most extreme of the 3-dimensional deformities that fulfilled the following criteria: (1) a minimum of 40° of scoliosis; (2) 2 or more levels of translation, anterior spondylolisthesis, and lateral subluxation (subluxation in 2 planes), causing symptomatic neurogenic claudication and severe spinal stenosis; and (3) lumbar hypokyphosis or flat-back syndrome. In addition, the majority had trunks that were out of balance (central sacral vertical line ?2 cm from vertical plumb line) or had sagittal imbalance, defined by a distance between the sagittal vertical line and S1 of greater than 3 cm. There were 25 patients who had severe enough deformities fulfilling these criteria that required supplementation of the lateral XLIF with posterior osteotomies and pedicle screw instrumentation. Results In our database, with a mean follow-up of 24 months, 85% of patients showed evidence of solid arthrodesis and no subsidence on computed tomography and flexion/extension radiographs. The complication rate remained low, with a perioperative rate of 2.4% and postoperative rate of 12.2%. The lateral listhesis and anterior spondylolisthetic subluxation were anatomically reduced with minimally invasive XLIF. The main finding in these 25 cases was our isolation of the major indication for supplemental posterior surgery: truncal decompensation in patients who are out of balance by 2 cm or more, in whom posterior spinal osteotomies and segmental pedicle screw instrumentation were required at follow up. No patients were out of sagittal balance (sagittal vertical line <3 cm from S1) postoperatively. Segmental instrumentation with osteotomies was also more effective for restoration of physiologic lumbar lordosis compared with anterior stand-alone procedures. Conclusions This retrospective study supports the finding that clinical outcomes (coronal/sagittal alignment) improve postoperatively after minimally invasive surgery with multilevel XLIF procedures and are improved compared with larger extensile thoracoabdominal anterior scoliosis procedures.

McAfee, Paul C.; Shucosky, Erin; Chotikul, Liana; Salari, Ben; Chen, Lun; Jerrems, Dan

2013-01-01

29

Comparison of adjacent segment disease after minimally invasive or open transforaminal lumbar interbody fusion.  

PubMed

Adjacent segment disease (ASD) is a potential long-term risk after lumbar fusion. Its incidence has been evaluated in anterior and posterior lumbar interbody fusions, but few studies have focused on transforaminal lumbar interbody fusion (TLIF). Relative risk of ASD with open or minimally invasive (MI) TLIF is poorly understood. To report our experience with risk for ASD in patients receiving TLIF and test its association with surgical approach, we performed a retrospective cohort study based on medical record review at a single institution. Eligible patients were ? 18 years old at operation, underwent single-level TLIF during the period 2007-2008, and had at least 6 months postoperative follow-up. Patients were categorized by surgical approach (open versus MI). Primary outcome of interest was development of symptomatic ASD, defined by (1) new back and/or leg pain, (2) imaging findings adjacent to original surgical level, and (3) decision to treat. A total of 68 patients (16 open, 52 MI) were included in the analysis. Groups had similar baseline characteristics, except the open group tended to be older (p=0.04). Seven (10%) patients developed ASD. Mean patient age was 62 years and three were male. Three underwent open and four underwent MI TLIF. Risk of ASD did not differ significantly by surgical approach. The MI group showed a trend toward decreased risk of ASD compared to the open group, although it was not statistically significant. This suggests MI TLIF may be associated with decreased long-term morbidity compared to the open approach. Large prospective studies are needed to confirm these findings. PMID:24880486

Yee, Timothy J; Terman, Samuel W; La Marca, Frank; Park, Paul

2014-10-01

30

A Meta-Analysis of Unilateral versus Bilateral Pedicle Screw Fixation in Minimally Invasive Lumbar Interbody Fusion  

PubMed Central

Study Design Meta-analysis. Background Bilateral pedicle screw fixation (PS) after lumbar interbody fusion is a widely accepted method of managing various spinal diseases. Recently, unilateral PS fixation has been reported as effective as bilateral PS fixation. This meta-analysis aimed to comparatively assess the efficacy and safety of unilateral PS fixation and bilateral PS fixation in the minimally invasive (MIS) lumbar interbody fusion for one-level degenerative lumbar spine disease. Methods MEDLINE/PubMed, EMBASE, BIOSIS Previews, and Cochrane Library were searched through March 30, 2014. Randomized controlled trials (RCTs) and controlled clinical trials (CCTs) on unilateral versus bilateral PS fixation in MIS lumbar interbody fusion that met the inclusion criteria and the methodological quality standard were retrieved and reviewed. Data on participant characteristics, interventions, follow-up period, and outcomes were extracted from the included studies and analyzed by Review Manager 5.2. Results Six studies (5 RCTs and 1 CCT) involving 298 patients were selected. There were no significant differences between unilateral and bilateral PS fixation procedures in fusion rate, complications, visual analogue score (VAS) for leg pain, VAS for back pain, Oswestry disability index (ODI). Both fixation procedures had similar length of hospital stay (MD?=?0.38, 95% CI?=??0.83 to 1.58; P?=?0.54). In contrast, bilateral PS fixation was associated with significantly more intra-operative blood loss (P?=?0.002) and significantly longer operation time (P?=?0.02) as compared with unilateral PS fixation. Conclusions Unilateral PS fixation appears as effective and safe as bilateral PS fixation in MIS lumbar interbody fusion but requires less operative time and causes less blood loss, thus offering a simple alternative approach for one-level lumbar degenerative disease. PMID:25375315

Liu, Zheng; Fei, Qi; Wang, Bingqiang; Lv, Pengfei; Chi, Cheng; Yang, Yong; Zhao, Fan; Lin, Jisheng; Ma, Zhao

2014-01-01

31

Endoscopic transforaminal decompression, interbody fusion, and percutaneous pedicle screw implantation of the lumbar spine: A case series report  

PubMed Central

Background On the basis of the experiences gained from conventional open spinal procedures, a long list of desirable objectives have emerged with the evolution of the lesser invasive spinal procedures. At the top of that list is the desire to minimize the trauma of surgery. The rest of the objectives, which include reductions of operating time, surgical blood loss, hospital stay, postoperative narcotic medication, convalescence, complication rates, and escalating health care costs, as well as the desire of elderly patients to continue rigorous physical activities, largely depend on the ability to minimize the trauma of surgery. The purpose of this study was to investigate the feasibility of the least invasive lumbar decompression, interbody fusion and percutaneous pedicle screw implantation, to minimize surgical trauma without compromising the quality of the treatment outcome, as well as to minimize risk of complications. Methods In this case series, 60 patients with diagnoses of degenerative disc disease, degenerative motion segments with stenosis, and spondylolisthesis, in whom nonoperative treatments failed, were treated with endoscopic transforaminal decompression and interbody fusion by 1 surgeon in 2 centers. The outcome measures were as follows: operating time, intraoperative blood loss, hospital stay, Visual Analogue Scale (VAS) scores for back and leg pain, scores on the Roland-Morris Disability Questionnaire, and postoperative imaging studies. A consecutive series of patients who met the treatment criteria completed VAS forms and Roland-Morris questionnaires preoperatively. Surgical procedures included arthroscopic decompression of the foramina and the discs; endplate preparation and implantation of allograft bone chips and bone morphogenetic protein 2 on absorbable collagen sponge into the disc space; and percutaneous implantation of pedicle screws. Postoperatively, the patients again completed the VAS forms and Roland-Morris questionnaires. Their charts were reviewed for office notes, operative notes, hospital stay, medications, and imaging studies. The latest X-ray and computed tomography scan films were reviewed and analyzed. Patients were followed up for a minimum of 6 months. The literature was reviewed for comparison of outcomes. Results Sixty patients met the inclusion criteria. The mean age was 52.8 years. The duration of illness averaged 5 years. Follow-up ranged from 6 to 25 months, with a mean of 12 months. Preoperative diagnoses included degenerative disc disease, degenerative motion segments with stenosis, and spondylolisthesis. The mean time in the operating room was 2 hours 54 minutes. Estimated blood loss averaged 57.6 mL. The duration of the hospital stay averaged 2.6 days. Preoperative back pain and leg pain were significantly reduced (P < .005). Forty-seven imaging studies obtained at the last visit, including X-ray and computed tomography scans, showed solid fusion in 28 patients (59.6%), stable fixation in 17 (36.2%), and osteolysis around the pedicle screws in 2 (4.2%). All patients had improvement of motor function, whereas 2 patients complained of residual numbness. In addition, 8 patients (13%) complained of residual discomfort on extension of the lumbar spine. Two patients had pedicle screw–related complications requiring surgery. A review of the literature showed that endoscopic transforaminal decompression and interbody fusion performed better than open transforaminal lumbar interbody fusion/posterior lumbar interbody fusion, minimally invasive transforaminal lumbar interbody fusion, and extreme lateral lumbar interbody fusion, with regard to most parameters studied. Conclusions The endoscopic transforaminal lumbar decompression, interbody fusion, and percutaneous pedicle screw instrumentation consistently produced satisfactory results in all demographics. It performed better than the alternative procedures for most parameters studied.

Osman, Said G.

2012-01-01

32

Transforaminal Decompression and Interbody Fusion in the Treatment of Thoracolumbar Fracture and Dislocation with Spinal Cord Injury  

PubMed Central

Study Design A retrospective clinical study. Objective To evaluate the efficacy and safety of transforaminal decompression and interbody fusion in the treatment of thoracolumbar fracture and dislocation with spinal cord injury. Methods Twenty-six spinal cord injured patients with thoracolumbar fracture and dislocation were treated by transforaminal decompression and interbody fusion. The operation time, intraoperative blood loss, and complications were recorded; the Cobb angle and compressive rate (CR) of the anterior height of two adjacent vertebrae were measured; and the nerve injury was assessed according to sensory scores and motor scores of the American Spinal Injury Association (ASIA) standards for neurological classification of spinal cord injury. Results The operative time was 250±57 min, and intraoperative blood loss was 440±168 ml. Cerebrospinal leakage was detected and repaired during the operation in two patients. A total of 24 of 26 patients were followed up for more than 2 years. ASIA sensory scores and motor scores were improved significantly at 3 months and 6 months after operation; the Cobb angle and CR of the anterior height of two adjacent vertebrae were corrected and showed a significant difference at post-operation; and the values were maintained at 3 months after operation and the last follow-up. Conclusion We showed that transforaminal decompression together with interbody fusion is an alternative method to treat thoracolumbar fracture and dislocation. PMID:25148221

Wu, Ai-Min; Zheng, Yi-Jing; Lin, Yan; Wu, Yao-Sen; Mao, Fang-Min; Ni, Wen-Fei; Wang, Xiang-Yang; Xu, Hua-Zi

2014-01-01

33

Arthroscopic discectomy and interbody fusion of the thoracic spine: A report of ipsilateral 2-portal approach  

PubMed Central

Background The standard approach to the thoracic disc is through thoracotomy. The video-assisted thoracoscopic approach has been used as an alternative to the open approach for nearly 20 years, and more recently, extracavitary, posterolateral approaches have been introduced. Both the transthoracic procedures involve deflating the lung for access to the spine, and postoperative thoracic drainage is necessary; postoperative morbidity can be significant. The retropleural procedures are in their infancy, but the published results are promising. The purpose of this study is to introduce the posterolateral arthroscopic thoracic decompression and fusion procedure, which is extrapleural, less disruptive to normal anatomy, and cost-effective. Methods Fifteen consecutive patients who underwent arthroscopic decompression and interbody fusion of the thoracic spine were prospectively studied according to the hospital's institutional review board protocol. The Short Form 36 and visual analog scale questionnaires were completed preoperatively and postoperatively. Paired t tests were used for statistical analysis. The patient was placed in the prone position on a radiolucent table, and instrumentation was performed under fluoroscopic control. Two portals were developed ipsilaterally (one for the arthroscope and the other for instruments) on the side of disc herniation, and a single portal was used on the contralateral side. Various instruments were used for disc excision and exploration of the spinal canal. Fusion was accomplished with bilateral corticocancellous dowels obtained from the iliac crests. Infiltration of the access channel and facet injections of the contiguous joints were performed with bupivacaine, for immediate postoperative pain control. Results Fifteen patients with a mean age of 54 years were followed up for 28 months postoperatively. The overall back pain score decreased from 7.2 (SD, 1.5) to 3 (SD, 2) after the procedure (P < .005). Eleven patients were satisfied with their current lifestyle postoperatively as opposed to one preoperatively. Two patients had reoccurrences. Hospital stay averaged 18.5 hours. The operating room cost and the cost of hospital stay was 51.9% of the cost of anterior open discectomy. Conclusions The extrapleural, biportal, ipsilateral arthroscopic approach for the decompression and interbody fusion of the thoracic spine is feasible, cost-effective, less traumatic, and associated with minimal complications. The best results were obtained in patients with single-level thoracic disc herniation. The technique is applicable for most thoracic disc herniations.

Osman, Said G.; Schwartz, Jeremy A.; Marsolais, E. B.

2012-01-01

34

Cantilever Transforaminal Lumbar Interbody Fusion for Upper Lumbar Degenerative Diseases (Minimum 2 Years Follow Up)  

PubMed Central

Purpose To evaluate the clinical outcomes of cantilever transforaminal lumbar interbody fusion (c-TLIF) for upper lumbar diseases. Materials and Methods Seventeen patients (11 males, 6 females; mean ± SD age: 62 ± 14 years) who underwent c-TLIF using kidney type spacers between 2002 and 2008 were retrospectively evaluated, at a mean follow-up of 44.1 ± 12.3 months (2 year minimum). The primary diseases studied were disc herniation, ossification of posterior longitudinal ligament (OPLL), degenerative scoliosis, lumbar spinal canal stenosis, spondylolisthesis, and degeneration of adjacent disc after operation. Fusion areas were L1-L2 (5 patients), L2-L3 (9 patients), L1-L3 (1 patient), and L2-L4 (2 patients). Operation time, blood loss, complications, Japanese Orthopaedic Association (JOA) score for back pain, bone union, sagittal alignment change of fusion level, and degeneration of adjacent disc were evaluated. Results JOA score improved significantly after surgery, from 12 ± 2 to 23 ± 3 points (p < 0.01). We also observed significant improvement in sagittal alignment of the fusion levels, from - 1.0 ± 7.4 to 5.2 ± 6.1 degrees (p < 0.01). Bony fusion was obtained in all cases. One patient experienced a subcutaneous infection, which was cured by irrigation. At the final follow-up, three patients showed degenerative changes in adjacent discs, and one showed corrective loss of fusion level. Conclusion c-TLIF is a safe procedure, providing satisfactory results for patients with upper lumbar degenerative diseases. PMID:21319352

Hioki, Akira; Hosoe, Hideo; Sugiyama, Seiichi; Suzuki, Naoki; Shimizu, Katsuji

2011-01-01

35

Comparing Miniopen and Minimally Invasive Transforaminal Interbody Fusion in Single-Level Lumbar Degeneration  

PubMed Central

Degenerative diseases of the lumbar spine, which are common among elderly people, cause back pain and radicular symptoms and lead to a poor quality of life. Lumbar spinal fusion is a standardized and widely accepted surgical procedure used for treating degenerative lumbar diseases; however, the classical posterior approach used in this procedure is recognized to cause vascular and neurologic damage of the lumbar muscles. Various studies have suggested that using the minimally invasive transforaminal interbody fusion (TLIF) technique provides long-term clinical outcomes comparable to those of open TLIF approaches in selected patients. In this study, we compared the perioperative and short-term advantages of miniopen, MI, and open TLIF. Compared with open TLIF, MI-TLIF and miniopen TLIF were associated with less blood loss, shorter hospital stays, and longer operative times; however, following the use of these procedures, no difference in quality of life was measured at 6 months or 1 year. Whether miniopen TLIF or MI-TLIF can replace traditional TLIF as the surgery of choice for treating degenerative lumbar deformity remains unclear, and additional studies are required for validating the safety and efficiency of these procedures. PMID:25629037

Lo, Wei-Lun; Lin, Chien-Min; Yeh, Yi-Shian; Tseng, Yuan-Yun; Yang, Shun-Tai

2015-01-01

36

Instrumented transforaminal lumbar interbody fusion in surgical treatment of recurrent disc herniation  

PubMed Central

Background: The incidence of recurrence in patients undergoing primary discectomy due to lumbar disc herniation (LDH), is regularly reported as 5-15%. In this study we aimed to evaluate surgical outcome of instrumented transforaminal lumbar interbody fusion (TLIF) in the patients suffering from recurrent LDH. Methods: We retrospectively studied 51 patients (30 female, 21 male) from August 2007 to October 2011. The mean age and follow-up of the patients was 46.4±14.8 (ranged; 29-77 years old) and 31.4±6.8 (ranged; 25-50 months), respectively. Clinical improvement was assessed by Oswestry Disability Index (ODI), visual analogue scale (VAS), and subjective satisfaction rate, while fusion was appraised radiologically. Data analysis was by one sample Kolmogorov-Smirnov, paired t, and Mann-Whitney tests. Results: Surgery could significantly improve mean leg and lumbar VAS and ODI from preoperative 7.4±2.5, 7.8±3.1, and 72.1±21.5 to postoperative 3.4±3.6, 3.5±2.6, and 27.5±18.0, respectively at the last follow-up visit. Subjective satisfaction rate was excellent in 24 patients (47.1%), good in 14 (27.5%), fair 11 (21.6%), and poor in two (3.9%). We had one patient with iatrogenic partial L5 nerve root injury and one with unknown late onset refractory postoperative back pain. Fusion rate was 100% and instrument failure was nil. Conclusion: In surgical treatment of the patients with recurrent LDH, bilaterally instrumented TLIF is a relatively safe and effective procedure and can be associated with least instrument failure and highest fusion rate while no postoperative bracing is also needed.

Omidi-Kashani, Farzad; Ghayem Hasankhani, Ebrahim; Noroozi, Hamid Reza

2014-01-01

37

Porous biodegradable lumbar interbody fusion cage design and fabrication using integrated global-local topology optimization with laser sintering.  

PubMed

Biodegradable cages have received increasing attention for their use in spinal procedures involving interbody fusion to resolve complications associated with the use of nondegradable cages, such as stress shielding and long-term foreign body reaction. However, the relatively weak initial material strength compared to permanent materials and subsequent reduction due to degradation may be problematic. To design a porous biodegradable interbody fusion cage for a preclinical large animal study that can withstand physiological loads while possessing sufficient interconnected porosity for bony bridging and fusion, we developed a multiscale topology optimization technique. Topology optimization at the macroscopic scale provides optimal structural layout that ensures mechanical strength, while optimally designed microstructures, which replace the macroscopic material layout, ensure maximum permeability. Optimally designed cages were fabricated using solid, freeform fabrication of poly(?-caprolactone) mixed with hydroxyapatite. Compression tests revealed that the yield strength of optimized fusion cages was two times that of typical human lumbar spine loads. Computational analysis further confirmed the mechanical integrity within the human lumbar spine, although the pore structure locally underwent higher stress than yield stress. This optimization technique may be utilized to balance the complex requirements of load-bearing, stress shielding, and interconnected porosity when using biodegradable materials for fusion cages. PMID:23897113

Kang, Heesuk; Hollister, Scott J; La Marca, Frank; Park, Paul; Lin, Chia-Ying

2013-10-01

38

Durotomy repair in minimally invasive transforaminal lumbar interbody fusion by nonpenetrating clips  

PubMed Central

Background: Closure of the dura defect may be easy to perform in open lumbar surgery but could be difficult in minimally invasive transforaminal lumbar interbody fusions (MIS-TLIF) since MIS-TLIF was done through a small tube, which limited the use of standard dural repair instruments. We used nonpenetrating titanium clips that were originally designed for the vascular anastomoses to repair the dura defect, which is never described in the literature. Methods: We presented a case of spinal stenosis with incidental durotomy while performing MIS-TLIF. We closed the dura laceration with three medium-sized nonpenetrating titanium clips (AnastoClip Vessel Closure System, LeMaitre Vascular, Inc., Burlington, MA). Results: Nonpenetrating titanium clips have the benefits of being technically easy to use, reduced durotomy repair time, decreased bed rest due to related medical complications, superior postoperation with immediate hydrostatic strength, and better reapproximation if it fails to clip successfully. As for the postoperation follow up, clips are tiny and reveal no obvious artifact, especially in cases where the pedicle screws are already causing much artifact. Conclusion: Primary dural closure during MIS-TLIF with clips is an effective way in cases that involve limited tubular space. PMID:24818043

Cheng, Yen-Po; Lin, Ping-Yi; Huang, Abel Po-Hao; Cheng, Chun-Yuan; Chen, Chien-Min; Hueng, Dueng-Yuan

2014-01-01

39

Anterior Dislodgement of a Fusion Cage after Transforaminal Lumbar Interbody Fusion for the Treatment of Isthmic Spondylolisthesis  

PubMed Central

Transforaminal lumbar interbody fusion (TLIF) is commonly used procedure for spinal fusion. However, there are no reports describing anterior cage dislodgement after surgery. This report is a rare case of anterior dislodgement of fusion cage after TLIF for the treatment of isthmic spondylolisthesis with lumbosacral transitional vertebra (LSTV). A 51-year-old man underwent TLIF at L4-5 with posterior instrumentation for the treatment of grade 1 isthmic spondylolisthesis with LSTV. At 7 weeks postoperatively, imaging studies demonstrated that banana-shaped cage migrated anteriorly and anterolisthesis recurred at the index level with pseudoarthrosis. The cage was removed and exchanged by new cage through anterior approach, and screws were replaced with larger size ones and cement augmentation was added. At postoperative 2 days of revision surgery, computed tomography (CT) showed fracture on lateral pedicle and body wall of L5 vertebra. He underwent surgery again for paraspinal decompression at L4-5 and extension of instrumentation to S1 vertebra. His back and leg pains improved significantly after final revision surgery and symptom relief was maintained during follow-up period. At 6 months follow-up, CT images showed solid fusion at L4-5 level. Careful cage selection for TLIF must be done for treatment of spondylolisthesis accompanied with deformed LSTV, especially when reduction will be attempted. Banana-shaped cage should be positioned anteriorly, but anterior dislodgement of cage and reduction failure may occur in case of a highly unstable spine. Revision surgery for the treatment of an anteriorly dislodged cage may be effectively performed using an anterior approach. PMID:24175028

Oh, Hyeong Seok; Lee, Sang-Ho

2013-01-01

40

A minimally invasive posterior lumbar interbody fusion using percutaneous long arm pedicle screw system for degenerative lumbar disease  

PubMed Central

The aim of this study is to evaluate the therapeutic efficacy of patients with lumbar degeneration and instability treated with percutaneous pedicle screw fixation and minimally invasive lumbar interbody fusion. Twenty-one patients were selected in our hospital from November, 2012 to March, 2013. The patients with an average age 55.62 years, including 8 vertebral spondylolisthesis, 4 lumbar intervertebral disc herniation, and 9 lumbar spinal canal stenosis cases. All the patients were managed to take the lumbar MRI and radiographs. The comparison of preoperative and postoperative (3 days, 2 weeks, 3 months) VAS and ODI score were analyzed. The results indicated that VAS scores were 7.14 ± 0.79 before operation, and 5.19 ± 0.81 in 3 days after operation, 4 ± 0.84 after 2 weeks, and 2.67 ± 0.66 after 3 months. The pain was relieved, and the postoperative VAS score was lower than that before treatment (P < 0.05). ODI score was 55.8 ± 11.4 before operation, 47.38 ± 9.38 after 3 days, 41.38 ± 8.09 after 2 weeks, 35.76 ± 4.50 after 3 months. ODI score was obviously decreased (P < 0.05). In conclusion, percutaneous pedicle screw fixation combined with minimally invasive interbody fusion is a safe, effective, feasible minimally invasive spine operation, with worthy for spreading.

He, Er-Xing; Cui, Ji-Hao; Yin, Zhi-Xun; Li, Chuang; Tang, Cheng; He, Yi-Qian; Liu, Cheng-Wei

2014-01-01

41

Posterior Lumbar Interbody Fusion Using Compressive Bone Graft with Allograft and Autograft in the Pyogenic Discitis  

PubMed Central

Study Design This is a retrospective study. Purpose To evaluate the advantages and effects of posterior lumbar interbody fusion (PLIF) using allograft and posterior instrumentation in the lumbar pyogenic discitis, which are resistant to antibiotics. Overview of Literature To present preliminary results of PLIF using a compressive bone graft with allograft and pedicle screw fixation in the lumbar pyogenic discitis. Methods Fifteen patients who had lumbar pyogenic discitis were treated by posterior approach from May 2004 to July 2008. The mean follow-up duration was 27.2 ± 18.68 months. The standing radiographs of the lumbar spine and clinical results were compared and analyzed in order to assess the bony union, the changes in the distance between the two vertebral bodies and the changes in the lordotic angle formed between the fused bodies immediately after surgery and at the final follow-up. Results Fifteen solid unions at an average of 15.2 ± 3.5 weeks after operation. The mean preoperative lordotic angle of the affected segments was 14.3 ± 15.1°, compared to 20.3 ± 12.3° after surgery and 19.8 ± 15.2° at last follow-up. For the functional result according to the Kirkaldy-Willis criteria, the outcome was excellent in 9, good in 5, fair in 1, and there were no poor cases. The average visual analogue scale score was decreased from 7.4 before surgery to 3.4 at 2 weeks postoperative. Conclusions The main advantage in the procedure of PLIF using compressive bone graft with allograft and post instrumentation is early ambulation. We believe that this is another good procedure for patients with poor general condition because a further autograft bone harvest is not required. PMID:22439083

An, Ki Chan; Kim, Tae Hyoung; Kim, Jin Suck; Park, Dae Hyoun; Kim, Jeon Gyo; Sung, Tae Woo

2012-01-01

42

Clinical and Radiological Outcomes of a New Cage for Direct Lateral Lumbar Interbody Fusion  

PubMed Central

Objective In Korea, direct lateral interbody fusion (DLIF) was started since 2011, using standard cage (6° lordotic angle, 18mm width). Recently, a new wider cage with higher lordotic angle (12°, 22mm) was introduced. The aim of our study is to compare the clinical and radiologic outcomes of the two cage types. Methods We selected patients underwent DLIF, 125 cases used standard cages (standard group) and 38 cases used new cages (wide group). We followed them up for more than 6 months, and their radiological and clinical outcomes were analyzed retrospectively. For radiologic outcomes, lumbar lordotic angle (LLA), segmental lordoic angle (SLA), disc angle (DA), foraminal height change (FH), subsidence and intraoperative endplate destruction (iED) were checked. Clinical outcomes were compared using visual analog scale (VAS) score, Oswestry disability index (ODI) score and complications. Results LLA and SLA showed no significant changes postoperatively in both groups. DA showed significant increase after surgery in the wide group (p<0.05), but not in the standard group. Subsidence was significantly lower in the wide group (p<0.05). There was no difference in clinical outcomes between the two groups. Additional posterior decompression was done more frequently in the wide group. Postoperative change of foraminal height was significantly lower in the wide group (p<0.05). The iED was observed more frequently in the wide group (p<0.05) especially at the anterior edge of cage. Conclusion The new type of cage seems to result in more DA and less subsidence. But indirect foraminal decompression seems to be less effective than standard cage. Intraoperative endplate destruction occurs more frequently due to a steeper lordotic angle of the new cage. PMID:25346760

Kim, Shin Jae; Lee, Young Seok; Kim, Young Baeg; Hung, Vo Tan

2014-01-01

43

Transforaminal lumbar interbody fusion rates in patients using a novel titanium implant and demineralized cancellous allograft bone sponge  

PubMed Central

Background Transforaminal lumbar interbody fusion (TLIF) with grafting and implant options like iliac crest bone graft (ICBG), recombinant bone morphogenetic protein (rhBMP), and polyetheretherketone (PEEK) cages have been reported to achieve extremely high fusion rates. Unfortunately, these options have also been frequently cited in the literature as causing postoperative morbidity and complications at a high cost. Knowing this, we sought to investigate TLIF using an acid-etched, roughened titanium cage that upregulates osteogenesis to see if similar fusion rates to those cited for ICBG, rhBMP, and PEEK cages could be safely achieved with minimal morbidity and complications. Materials and methods A radiographic fusion study of 82 patients who underwent TLIF using an acid-etched, roughened titanium cage with demineralized cancellous bone graft was conducted. Fusion was assessed and graded by an independent radiologist using computed tomography scan with sagittal and coronal reconstructions. Results Fusion rates at 6 months were 41 of 44 (93.2%) and at 12 months were 37 of 38 (97.4%). There were no radiographic device-related complications. Conclusions TLIF with an acid-etched, roughened titanium cage filled with a decalcified bone graft achieved similar fusion rates to historical controls using ICBG, rhBMP, and PEEK. PMID:25580378

Girasole, Gerard; Muro, Gerard; Mintz, Abraham; Chertoff, Jason

2014-01-01

44

Clinical and Radiological Outcomes of Unilateral Facetectomy and Interbody Fusion Using Expandable Cages for Lumbosacral Foraminal Stenosis  

PubMed Central

Objective Surgical treatment of lumbosacral foraminal stenosis requires an understanding of the anatomy of the lumbosacral area in individual patients. Unilateral facetectomy has been used to completely decompress entrapment of the L5 nerve root, followed in some patients by posterior lumbar interbody fusion (PLIF) with stand-alone cages. Methods We assessed 34 patients with lumbosacral foraminal stenosis who were treated with unilateral facetectomy and PLIF using stand-alone cages in our center from January 2004 to September 2007. All the patients underwent follow-up X-rays, including a dynamic view, at 3, 6, 12, 24 months, and computed tomography (CT) at 24 months postoperatively. Clinical outcomes were analyzed with the mean numeric rating scale (NRS), Oswestry Disability Index (ODI) and Odom's criteria. Radiological outcomes were assessed with change of disc height, defined as the average of anterior, middle, and posterior height in plain X-rays. In addition, lumbosacral fusion was also assessed with dynamic X-ray and CT. Results Mean NRS score, which was 9.29 prior to surgery, was 1.5 at 18 months after surgery. The decrease in NRS was statistically significant. Excellent and good groups with regard to Odom's criteria were 31 cases (91%) and three cases (9%) were fair. Pre-operative mean ODI of 28.4 decreased to 14.2 at post-operative 24 months. In 30 patients, a bone bridge on CT scan was identified. The change in disc height was 8.11 mm, 10.02 mm and 9.63 mm preoperatively, immediate postoperatively and at 24 months after surgery, respectively. Conclusion In the treatment of lumbosacral foraminal stenosis, unilateral facetectomy and interbody fusion using expandable stand-alone cages may be considered as one treatment option to maintain post-operative alignment and to obtain satisfactory clinical outcomes. PMID:21430975

Park, Jin Hoon; Bae, Chae Wan; Jeon, Sang Ryong; Rhim, Seung Chul; Kim, Chang Jin

2010-01-01

45

Clinical and radiographic outcomes of extreme lateral approach to interbody fusion with ?-tricalcium phosphate and hydroxyapatite composite for lumbar degenerative conditions  

PubMed Central

Background Historically, iliac crest bone graft has been used as the graft of choice for lumbar spine fusion procedures. Because fusion techniques have become less invasive, the demand for minimally disruptive grafting options has increased. This prospective study was performed to assess clinical and radiographic outcomes of patients treated with an iliac crest bone graft alternative and lateral lumbar interbody fusion. Methods Fifty degenerative lumbar patients were treated with the extreme lateral approach to interbody fusion and a ?-tricalcium phosphate–hydroxyapatite graft with bone marrow aspirate (BMA) at 1 or 2 adjacent levels. BMA was collected from the iliac crest with a bone aspiration needle and applied to the FormaGraft (NuVasive, Inc., San Diego, California) in a 1:1 ratio. Radiolucent cages were filled with FormaGraft strips, granules, or blocks and implanted in a standard fashion. Clinical data were collected at baseline, 6 weeks, and 3, 6, and 12 months and included visual analog scale, Oswestry Disability Index, and Short Form 36 patient-reported assessments. Fusion assessments were made from neutral anteroposterior/lateral radiographs, lateral flexion/extension radiographs, and computed tomography images taken at least 12 months after surgery. Results Forty-four patients treated at 49 levels completed follow-up. The mean patient age was 54.7 ± 10.8 years, and mean body mass index was 30.8 ± 7.7 kg/m2. Radiographic fusion was observed in 41 of 44 assessed levels (93.2%). Blood loss was less than 100 mL in 95.5% of patients. Of the patients, 93.2% spent 1 night or less in the hospital. By the 6-week follow-up, all clinical outcomes were significantly improved (P < .05). Improvements were maintained or increased throughout the course of follow-up. Conclusions This report shows that the technique of extreme lateral approach to interbody fusion in combination with FormaGraft and BMA in the interbody space is a safe and effective treatment option for interbody fusion of the lumbar spine when compared with other approaches and biologic options.

Rodgers, W. Blake; Gerber, Edward J.; Rodgers, Jody A.

2012-01-01

46

Minimally Invasive Transforaminal Lumbar Interbody Fusion with Unilateral Pedicle Screw Fixation: Comparison between Primary and Revision Surgery  

PubMed Central

Minimally invasive surgery with a transforaminal lumbar interbody fusion (MIS TLIF) is an important minimally invasive fusion technique for the lumbar spine. Lumbar spine reoperation is challenging and is thought to have greater complication risks. The purpose of this study was to compare MIS TLIF with unilateral screw fixation perioperative results between primary and revision surgeries. This was a prospective study that included 46 patients who underwent MIS TLIF with unilateral pedicle screw. The patients were divided into two groups, primary and revision MIS TLIF, to compare perioperative results and complications. The two groups were similar in age, sex, and level of operation, and were not significantly different in the length of follow-up or clinical results. Although dural tears were more common with the revision group (primary 1; revision 4), operation time, blood loss, total perioperative complication, and fusion rates were not significantly different between the two groups. Both groups showed substantial improvements in VAS and ODI scores one year after surgical treatment. Revision MIS TLIF performed by an experienced surgeon does not necessarily increase the risk of perioperative complication compared with primary surgery. MIS TLIF with unilateral pedicle screw fixation is a valuable option for revision lumbar surgery. PMID:24949483

Kang, Moo Sung; Kim, Kyung Hyun; Kuh, Sung Uk; Chin, Dong Kyu; Kim, Keun Su; Cho, Yong Eun

2014-01-01

47

The value of adding posterior interbody fusion in the surgical treatment of degenerative lumbar spine disorders: A systematic review  

PubMed Central

Background Posterolateral fusion (PF) is a common method by which to achieve fusion in lumbar spine surgery. It has been reported that posterior interbody fusion (PIF) yields a higher fusion rate and a better functional and clinical outcome. Our objective was to determine whether PIF improves the clinical and radiologic outcomes in adults surgically treated for degenerative lumbar spine conditions compared with PF. Methods We performed a systematic search of electronic databases, bibliographies, and relevant journals and meta-analyses. Results Of 2798 citations identified, 5 studies met our inclusion criteria (none of which was a randomized controlled trial), with a total of 148 patients in the PIF group (intervention) and 159 in the PF group (control). Pooled meta-analyses showed that nonunion rates were lower in the intervention group (relative risk, 0.22; 95% confidence interval [CI], 0.08–0.62). The intervention group had a significantly higher disc height (weighted mean difference, 3.2 mm; 95% CI, 1.9–4.4 mm) and lower residual percent slippage (weighted mean difference, 6.3%; 95% CI, 3.9%–8.7%) at final follow-up. There were no significant differences in segmental or total lumbar lordosis. Because of heterogeneity of results, no conclusions could be made with regard to functional benefits. Conclusions This review suggests that PIF achieves a higher fusion rate and better correction of certain radiographic aspects of deformity over PF. It also showed a slight but not significant trend toward a better functional outcome in the PIF group. The lack of randomized controlled trials and the methodologic limitations of the available studies call for the planning and conduct of a sufficiently sized, methodologically sound study with clinically relevant outcome measures. Until this has been done, the current evidence regarding the beneficial effects of PIF should be interpreted with caution.

Fallatah, Salah; Wai, Eugene; Baily, Christopher S.

2013-01-01

48

Minimally invasive trans-sacral approach to L5-S1 interbody fusion: Preliminary results from 1 center and review of the literature  

PubMed Central

Background Lumbar interbody fusion has long been used for the treatment of painful degenerative spinal conditions. The anterior approach is not feasible in some patients, and the posterior approach is associated with a risk of neural complications and possibly muscle injury. A trans-sacral technique was developed that allows access to the L5-S1 disc space. The purposes of this study were to investigate the clinical outcome of trans-sacral interbody fusion in a consecutive series of patients from 1 center and to perform a comprehensive review of the literature on this procedure. Methods A literature search using PubMed was performed to identify articles published on trans-sacral axial lumbar interbody fusion (AxiaLIF). Articles reviewed included biomechanical testing, feasibility of the technique, and clinical results. The data from our center were collected retrospectively from charts for the consecutive series, beginning with the first case, of all patients undergoing fusion using the AxiaLIF technique. In most cases, posterior instrumentation was also used. A total of 41 patients with at least 6 months’ follow-up were included (mean follow-up, 22.2 months). The primary clinical outcome measures were visual analog scales separately assessing back and leg pain and the Oswestry Disability Index. Radiographic assessment of fusion was also performed. Results In the group of 28 patients undergoing single-level AxiaLIF combined with posterior fusion, the visual analog scale scores assessing back and leg pain and mean Oswestry Disability Index scores improved significantly (P < .01). In the remaining 13 patients, back pain improved significantly with a trend for improvement in leg pain. Reoperation occurred in 19.5% of patients; in half of these, reoperation was not related to the anterior procedure. Conclusions A review of the literature found that the AxiaLIF technique was similar to other fusion techniques with respect to biomechanical properties and produced acceptable clinical outcomes, although results varied among studies. Clinical relevance The AxiaLIF approach allows access to the L5-S1 interspace without violating the annulus or longitudinal ligaments and with minimal risk to dorsal neural elements. It may be a viable alternative to other approaches to interbody fusion at the L5-S1 level. It is important that the patients be selected carefully and surgeons are familiar with the presacral anatomy and the surgical approach.

Bradley, W. Daniel; Hisey, Michael S.; Verma-Kurvari, Sunita; Ohnmeiss, Donna D.

2012-01-01

49

Structural and mechanical evaluations of a topology optimized titanium interbody fusion cage fabricated by selective laser melting process.  

PubMed

A topology optimized lumbar interbody fusion cage was made of Ti-Al6-V4 alloy by the rapid prototyping process of selective laser melting (SLM) to reproduce designed microstructure features. Radiographic characterizations and the mechanical properties were investigated to determine how the structural characteristics of the fabricated cage were reproduced from design characteristics using micro-computed tomography scanning. The mechanical modulus of the designed cage was also measured to compare with tantalum, a widely used porous metal. The designed microstructures can be clearly seen in the micrographs of the micro-CT and scanning electron microscopy examinations, showing the SLM process can reproduce intricate microscopic features from the original designs. No imaging artifacts from micro-CT were found. The average compressive modulus of the tested caged was 2.97+/-0.90 GPa, which is comparable with the reported porous tantalum modulus of 3 GPa and falls between that of cortical bone (15 GPa) and trabecular bone (0.1-0.5 GPa). The new porous Ti-6Al-4V optimal-structure cage fabricated by SLM process gave consistent mechanical properties without artifactual distortion in the imaging modalities and thus it can be a promising alternative as a porous implant for spine fusion. PMID:17415762

Lin, Chia-Ying; Wirtz, Tobias; LaMarca, Frank; Hollister, Scott J

2007-11-01

50

Lateral retroperitoneal transpsoas interbody fusion in a patient with achondroplastic dwarfism.  

PubMed

The authors present the first reported use of the lateral retroperitoneal transpsoas approach for interbody arthrodesis in a patient with achondroplastic dwarfism. The inherent anatomical abnormalities of the spine present in achondroplastic dwarfism predispose these patients to an increased incidence of spinal deformity as well as neurogenic claudication and potential radicular symptoms. The risks associated with prolonged general anesthesia and intolerance of significant blood loss in these patients makes them ideal candidates for minimally invasive spinal surgery. The patient in this case was a 51-year-old man with achondroplastic dwarfism who had a history of progressive claudication and radicular pain despite previous extensive lumbar laminectomies. The lateral retroperitoneal transpsoas approach was used for placement of interbody cages at L1/2, L2/3, L3/4, and L4/5, followed by posterior decompression and pedicle screw instrumentation. The patient tolerated the procedure well with no complications. Postoperatively his claudicatory and radicular symptoms resolved and a CT scan revealed solid arthrodesis with no periimplant lucencies. PMID:25415482

Staub, Blake N; Holman, Paul J

2015-02-01

51

Nerve root anomalies: implications for transforaminal lumbar interbody fusion surgery and a review of the Neidre and Macnab classification system.  

PubMed

Lumbar nerve root anomalies are uncommon phenomena that must be recognized to avoid neural injury during surgery. The authors describe 2 cases of nerve root anomalies encountered during mini-open transforaminal lumbar interbody fusion (TLIF) surgery. One anomaly was a confluent variant not previously classified; the authors suggest that this variant be reflected in an amendment to the Neidre and Macnab classification system. They also propose strategies for identifying these anomalies and avoiding injury to anomalous nerve roots during TLIF surgery. Case 1 involved a 68-year-old woman with a 2-year history of neurogenic claudication. An MR image demonstrated L4-5 stenosis and spondylolisthesis and an L-4 nerve root that appeared unusually low in the neural foramen. During a mini-open TLIF procedure, a nerve root anomaly was seen. Six months after surgery this patient was free of neurogenic claudication. Case 2 involved a 60-year-old woman with a 1-year history of left L-4 radicular pain. Both MR and CT images demonstrated severe left L-4 foraminal stenosis and focal scoliosis. Before surgery, a nerve root anomaly was not detected, but during a unilateral mini-open TLIF procedure, a confluent nerve root was identified. Two years after surgery, this patient was free of radicular pain. PMID:23905960

Burke, Shane M; Safain, Mina G; Kryzanski, James; Riesenburger, Ron I

2013-08-01

52

Prospective Randomized Controlled Trial of The Stabilis Stand Alone Cage (SAC) Versus Bagby and Kuslich (BAK) Implants for Anterior Lumbar Interbody Fusion  

PubMed Central

Background Degenerative disc disease is common and debilitating for many patients. If conservative extensive care fails, anterior lumbar interbody fusion has proven to be an alternative form of surgical management. The Stabilis Stand Alone Cage(SAC) was introduced as a method to obtain stability and fusion. The purpose of this study was to determine whether the Stabilis Stand Alone Cage (SAC) is comparable in safety and efficacy to the Bagby and Kuslich (BAK) device. Methods As part of a prospective, randomized, controlled FDA trial, 73 patients underwent anterior interbody fusion using either the SAC(56%) or the BAK device (44%). Results Background characteristics were similar between the two groups. There was no significant difference between the SAC and BAK groups in mean operative time or mean blood loss during surgery. Adverse event rates did not differ between the groups. Assessment of plain radiographs could not confirm solid fusion in 63% of control and 71% of study patients. Functional scores from Owestry and SF-36 improved in both groups by the two-year follow-up. There were no significant differences between the SAC and BAK patients with respect to outcome. Conclusions Both the Stabilis Stand Alone Cage and the BAK Cage provided satisfactory improvement in function and pain relief, despite less than expected radiographic fusion rates. The apparent incongruency between fusion rates and functional outcomes suggests that either radiographs underestimate the true incidence of fusion, or that patients are obtaining good pain relief and improved function despite a lower rate of fusion than previously reported. This was a Level III study.

Lavelle, William; McLain, Robert F.; Rufo-Smith, Candace; Gurd, David P.

2014-01-01

53

Continuous somatosensory evoked potentials monitoring is highly sensitive to intraoperative occlusion of iliac artery during anterior lumbar interbody fusion: case report.  

PubMed

We report a case of thrombotic occlusion of the left common iliac artery during an L5-S1 anterior interbody fusion exposed via a retroperitoneal approach. The loss of distal blood flow was detected by loss of cortical and peripheral somatosensory evoked potentials on the left lower extremity. Restoration of the blood flow resulted in gradual return of evoked potentials of the involved extremity. The neurophysiological and pulse oximetry monitoring of the lower extremities are extremely sensitive for an early detection of thrombotic occlusions and vascular complications. PMID:19694209

Haghighi, S S; Zhang, R; Raiszadeh, R; Chammas, J; Bench, G; Raiszadeh, K; Terramanis, T T

2009-01-01

54

Osteoinductive activity of ErhBMP-2 after anterior cervical diskectomy and fusion with a ß-TCP interbody cage in a goat model.  

PubMed

Bone morphogenetic protein (BMP)-2 induces bone and cartilage tissue formation. Large amounts of BMP-2 are difficult to purify or to produce in vitro using eukaryotic cells. The goal of the present study was to assess the clinical use of Escherichia coli-derived recombinant human BMP-2 (ErhBMP-2) on bone fusion after cervical and lumbar spine surgery in a goat model, compared with the standard autogenous iliac bone grafting. Thirty-six goats were randomized to 3 groups: (A) autogenous iliac bone grafting, (B) cervical interbody fusion cage containing ß-tricalcium phosphate (ß-TCP), or (C) cervical interbody fusion cage containing ß-TCP+ErhBMP-2 (2.5 mg). Cervical bone repair was evaluated using radiographs and computed tomography scans at 0, 3, and 6 months. Histological analyses were performed on cervical samples. Two goats died from infection. The differences in intervertebral height among the groups were not significant 3 months postoperatively but became significant after 6 months between groups A vs B and C (P=.04); there was no difference between groups B and C at 6 months. Adding ErhBMP-2 significantly increased cervical fusion at 6 months (P=.04). Histological examinations showed that ß-TCP+ErhBMP-2 increased new bone area, material degradation rate, and depth of tissue penetration and decreased residual material area, all in a time-dependent manner. Escherichia coli-derived rhBMP-2 combined with an enhanced fusion cage containing ß-TCP induced bone formation in a goat model. Furthermore, its ability to promote bone fusion was similar to autogenous iliac bone grafting. PMID:24679197

Wang, Hongli; Zhang, Fan; Lv, Feizhou; Jiang, Jianyuan; Liu, Dayong; Xia, Xinlei

2014-02-01

55

Radiation exposure during the lateral lumbar interbody fusion procedure and techniques to reduce radiation dosage  

PubMed Central

Background Fluoroscopy is widely used in spine surgery to assist with graft and hardware placement. Previous studies have not measured radiation exposure to a surgeon during minimally invasive lateral lumbar spine surgery for single-level discectomy and interbody cage insertion. This study was performed to model and measure radiation exposure to a surgeon during spine surgery using the direct lateral lumbar procedure. Methods The study was performed using a mannequin substituting for the surgeon and a cadaver substituting for the patient. Radiation was measured with dosimeters attached to 6 locations on the mannequin using a OEC Medical Systems 9800 C-arm fluoroscope (OEC Medical Systems, Salt Lake City, Utah). Three different fluoroscopy setups were tested: a standard imaging setup, a standard setup using pulsed-mode fluoroscopy, and a reversed setup. The experiment was tested 5 times per setup, and the dosimeters’ values were recorded. Results The highest amount of radiation exposure occurred when obtaining an anteroposterior view of the spine in the standard setup. Compared with the standard setup, the pulsed-mode setting decreased the radiation exposure to the mannequin by a factor of 6 times (P < .001). Compared with the standard setup, the reversed setup also decreased the radiation exposure to the mannequin by a factor of 6 times (P < .001) and it had the lowest amount of radiation exposure to the eye level (P < .001). Conclusions Care should be taken when one is obtaining an anteroposterior view of the lumbar spine during lateral lumbar procedures to limit radiation exposure. Radiation exposure to the surgeon can be greatly minimized by using either a pulsed imaging mode or the reversed setup. The reversed setup has the lowest amount of radiation exposure to the eye level.

Tatsumi, Robert L.

2012-01-01

56

Intraoperative Neurophysiological Monitoring for Minimally Invasive 1- and 2-Level Transforaminal Lumbar Interbody Fusion: Does It Improve Patient Outcome?  

PubMed Central

Background Despite the widespread use of intraoperative monitoring (IOM) in many types of spinal surgeries, an absence of data comparing monitored a nd unmonitored postoperative outcomes places IOM's efficacy into question. A lack of consensus among surgeons about when to use monitoring also raises concerns about its overuse in routine and low-risk procedures. Methods We performed a retrospective database review of 112 patients undergoing a 1- or 2-level minimally invasive surgery transforaminal lumbar interbody fusion (MIS-TLIF). Our analysis focused on patient demographics, use of IOM, length of surgery, hospital length of stay, the perioperative complication of pedicle screw malposition, and average hospital cost. Results For the 73 patients who underwent MIS-TLIF with intraoperative neuromonitoring, their hospital length of stay (P=0.8) and need for pedicle screw revisions (P=0.93) were not statistically significant compared to the 39 patients who underwent MIS-TLIF procedures without IOM. The incidence of reoperation was 5.48% and 5.13%, and average length of stay was 3.25 days and 3.13 days, respectively. However, the cost of surgery and the length of surgery were significantly higher in the monitored group compared to the nonmonitored group (P=0.008 and P=0.009, respectively). Conclusion IOM is widely used in spine surgery, but our retrospective review shows that its use does not necessarily decrease the incidence of malpositioning of pedicle screws. In fact, no statistical difference was detected in the incidence of screw malposition in the 2 groups of patients. On the other hand, IOM adds cost and increases the length of surgery. Because the use of IOM did not make a difference in the incidence of pedicle screw malpositioning and because of the comparative cost analysis for both groups of patients, we believe that the use of IOM for MIS-TLIF provides no added benefit. PMID:24688334

Garces, Juanita; Berry, J. Franklin; Valle-Giler, Edison P.; Sulaiman, Wale A. R.

2014-01-01

57

Surgeons' Exposure to Radiation in Single- and Multi-Level Minimally Invasive Transforaminal Lumbar Interbody Fusion; A Prospective Study  

PubMed Central

Although minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) has widely been developed in patients with lumbar diseases, surgeons risk exposure to fluoroscopic radiation. However, to date, there is no studies quantifying the effective dose during MIS-TLIF procedure, and the radiation dose distribution is still unclear. In this study, the surgeons' radiation doses at 5 places on the bodies were measured and the effective doses were assessed during 31 consecutive 1- to 3-level MIS-TLIF surgeries. The operating surgeon, assisting surgeon, and radiological technologist wore thermoluminescent dosimeter on the unshielded thyroid, chest, genitals, right middle finger, and on the chest beneath a lead apron. The doses at the lens and the effective doses were also calculated. Mean fluoroscopy times were 38.7, 53.1, and 58.5 seconds for 1, 2, or 3 fusion levels, respectively. The operating surgeon's mean exposures at the lens, thyroid, chest, genitals, finger, and the chest beneath the shield, respectively, were 0.07, 0.07, 0.09, 0.14, 0.32, and 0.05 mSv in 1-level MIS-TLIF; 0.07, 0.08, 0.09, 0.18, 0.34, and 0.05 mSv in 2-level; 0.08, 0.09, 0.14, 0.15, 0.36, and 0.06 mSv in 3-level; and 0.07, 0.08, 0.10, 0.15, 0.33, and 0.05 mSv in all cases. Mean dose at the operating surgeon's right finger was significantly higher than other measurements parts (P<0.001). The operating surgeon's effective doses (0.06, 0.06, and 0.07 mSv for 1, 2, and 3 fusion levels) were low, and didn't differ significantly from those of the assisting surgeon or radiological technologist. Revision MIS-TLIF was not associated with higher surgeons' radiation doses compared to primary MIS-TLIF. There were significantly higher surgeons' radiation doses in over-weight than in normal-weight patients. The surgeons' radiation exposure during MIS-TLIF was within the safe level by the International Commission on Radiological Protection's guidelines. The accumulated radiation exposure, especially to surgeon's hands, should be carefully monitored. PMID:24736321

Funao, Haruki; Ishii, Ken; Momoshima, Suketaka; Iwanami, Akio; Hosogane, Naobumi; Watanabe, Kota; Nakamura, Masaya; Toyama, Yoshiaki; Matsumoto, Morio

2014-01-01

58

Quality-of-Life Outcomes With Minimally Invasive Transforaminal Lumbar Interbody Fusion Based on Long-Term Analysis of 304 Consecutive Patients  

PubMed Central

Study Design. This was a prospective clinical study that took place in an outpatient spine clinic. Objective. To demonstrate the short-/long-term outcomes from a large cohort of patients undergoing minimally invasive transforaminal lumbar interbody fusion (MITLIF). Summary of Background Data. Long-term prospective outcomes in patients undergoing minimally invasive spinal fusion for debilitating back pain has not been well studied. Methods. Presenting diagnosis was determined from clinical findings and radiographical (radiograph, magnetic resonance image, computed tomographic scan) evaluations preoperatively. Patients were assessed with outcome measures preoperatively, and postoperatively at 2 weeks, 3 months, 6 months, 12 months, 24 months, and annually 2 to 7 years (mean follow-up: 47 mo) final follow-up. The rate of postoperative complications and reoperations at the initial level of MITLIF and adjacent level(s) were followed. Fusion rates were assessed blinded and independently by radiograph. Results. Visual analogue scale scores decreased significantly from 7.0 preoperatively to 3.5 at mean 47-month follow-up. Oswestry Disability Index scores declined from 43.1 preoperatively to 28.2 at mean 47-month follow-up. Short-Form 36 mental component scores increased from 43.8 preoperatively to 49.7 at 47-month follow-up. Short-Form 36 physical component scores increased from 30.6 preoperatively to 39.6 at 47-month follow-up (P < 0.05). Conclusion. This prospectively collected outcomes study shows long-term statistically significant clinical outcomes improvement after MITLIF in patients with clinically symptomatic spondylolisthesis and degenerative disc disease with or without stenosis. MITLIF resulted in a high rate of spinal fusion and very low rate of interbody fusion failure and/or adjacent segment disease requiring reoperation while reducing postoperative complications. Level of Evidence: 3 PMID:24150437

Hussain, Namath S.; White, G. Zachary; Begun, Evan M.; Collins, Robert A.; Fahim, Daniel K.; Hiremath, Girish K.; Adbi, Fadumo M.; Yacob, Sammy A.

2014-01-01

59

A Multi-center Clinical Study of Posterior Lumbar Interbody Fusion with the Expandable Stand-alone Cage (Tyche® Cage) for Degenerative Lumbar Spinal Disorders  

PubMed Central

Objective This multi-center clinical study was designed to determine the long-term results of patients who received a one-level posterior lumbar interbody fusion with expandable cage (Tyche® cage) for degenerative spinal diseases during the same period in each hospital. Methods Fifty-seven patients with low back pain who had a one-level posterior lumbar interbody fusion using a newly designed expandable cage were enrolled in this study at five centers from June 2003 to December 2004 and followed up for 24 months. Pain improvement was checked with a Visual Analogue Scale (VAS) and their disability was evaluated with the Oswestry Disability Index. Radiographs were obtained before and after surgery. At the final follow-up, dynamic stability, quality of bone fusion, interveretebral disc height, and lumbar lordosis were assessed. In some cases, a lumbar computed tomography scan was also obtained. Results The mean VAS score of back pain was improved from 6.44 points preoperatively to 0.44 at the final visit and the score of sciatica was reduced from 4.84 to 0.26. Also, the Oswestry Disability Index was improved from 32.62 points preoperatively to 18.25 at the final visit. The fusion rate was 92.5%. Intervertebral disc height, recorded as 9.94±2.69 mm before surgery was increased to 12.23±3.31 mm at postoperative 1 month and was stabilized at 11.43±2.23 mm on final visit. The segmental angle of lordosis was changed significantly from 3.54±3.70° before surgery to 6.37±3.97° by 24 months postoperative, and total lumbar lordosis was 20.37±11.30° preoperatively and 24.71±11.70° at 24 months postoperative. Conclusion There have been no special complications regarding the expandable cage during the follow-up period and the results of this study demonstrates a high fusion rate and clinical success. PMID:19096552

Kim, Jin Wook; Yoon, Seung Hwan; Oh, Seong Hoon; Roh, Sung Woo; Rim, Dae Cheol; Kim, Tae Sung

2007-01-01

60

Functional outcomes of instrumented posterior lumbar interbody fusion in active-duty US servicemen  

Microsoft Academic Search

Background context: The existing literature lacks a functional outcome study addressing instrumented posterior lumbar fusion surgery in physically active patients. Furthermore, results of operative versus nonoperative treatment in these patients are not clear. Purpose: To evaluate patient-assessed function, pain, and satisfaction and military job performance between servicemen treated operatively and nonoperatively. Study design\\/setting: This is a nonrandomized analysis of consecutive

Major Robert W Molinari; Major Tad Gerlinger

2001-01-01

61

Biological performance of a polycaprolactone-based scaffold used as fusion cage device in a large animal model of spinal reconstructive surgery.  

PubMed

A bioactive and bioresorbable scaffold fabricated from medical grade poly (epsilon-caprolactone) and incorporating 20% beta-tricalcium phosphate (mPCL-TCP) was recently developed for bone regeneration at load bearing sites. In the present study, we aimed to evaluate bone ingrowth into mPCL-TCP in a large animal model of lumbar interbody fusion. Six pigs underwent a 2-level (L3/4; L5/6) anterior lumbar interbody fusion (ALIF) implanted with mPCL-TCP + 0.6 mg rhBMP-2 as treatment group while four other pigs implanted with autogenous bone graft served as control. Computed tomographic scanning and histology revealed complete defect bridging in all (100%) specimen from the treatment group as early as 3 months. Histological evidence of continuing bone remodeling and maturation was observed at 6 months. In the control group, only partial bridging was observed at 3 months and only 50% of segments in this group showed complete defect bridging at 6 months. Furthermore, 25% of segments in the control group showed evidence of graft fracture, resorption and pseudoarthrosis. In contrast, no evidence of graft fractures, pseudoarthrosis or foreign body reaction was observed in the treatment group. These results reveal that mPCL-TCP scaffolds could act as bone graft substitutes by providing a suitable environment for bone regeneration in a dynamic load bearing setting such as in a porcine model of interbody spine fusion. PMID:19540586

Abbah, Sunny A; Lam, Christopher X L; Hutmacher, Dietmar W; Goh, James C H; Wong, Hee-Kit

2009-10-01

62

Assessment of bone graft incorporation by 18?F-fluoride positron-emission tomography/computed tomography in patients with persisting symptoms after posterior lumbar interbody fusion  

PubMed Central

Background Posterior lumbar interbody fusion (PLIF) is a method that allows decompression of the spinal canal and nerve roots by laminectomy combined with fusion by means of intervertebral cages filled with bone graft and pedicle screw fixation. Conventional imaging techniques, such as plain radiography and computed tomography (CT), have limitations to assess bony fusion dynamics. Methods In 16 PLIFs of 15 patients with persisting symptoms, positron-emission tomography (PET)/CT scans were made 60?min after intravenous administration of 156 to 263?MBq of 18?F-fluoride, including 1-mm sliced, high-dose, non-contrast-enhanced CT scanning. Maximal standard uptake values (SUVmax) of various regions were calculated and correlated with abnormalities on CT. Results Subsidence of the cages into the vertebral endplates was the most frequently observed abnormality on CT (in 16 of 27 or 59% of evaluable endplates). Endplate SUVmax values were significantly higher for those patients with pronounced (p?fusion was seen on CT in 63% but showed no correlation to intercorporal SUVmax values. Conclusions With the use of 18?F-fluoride PET/CT, intervertebral cage subsidence appeared to be a prominent finding in this patient group with persisting symptoms, and highly correlating with the degree of PET hyperactivity at the vertebral endplates and pedicle screw entry points. Further study using 18?F-fluoride PET/CT should specifically assess the role of metabolically active subsidence in a prospective patient group, to address its role in nonunion and as a cause of persisting pain. PMID:22846374

2012-01-01

63

Mid-term Clinical Outcomes of Stand-alone Posterior Interbody Fusion with Rectangular Cages: A 4-year-minimum Follow-up  

PubMed Central

Objective We sought to determine minimum 4 years of clinical outcomes including fusion rate, revision rate and complications of patients who underwent placement of rectangular stand-alone cages. Methods Thirty-three cases of degenerative spine that had been followed for at least 4-years were reviewed retrospectively. Cages were inserted at L4-L5 level or L5-S1 in 27 or in 6 cases respectively. Visual analogue scale (VAS), Odom's criteria, fusion rate, intervertebral disc height and lumbar lordosis were determined pre- and post-operatively on standing x-rays. Amount of intra- and postoperative blood loss, total volume transfused, duration of surgery and perioperative complications were also evaluated. Results The mean VAS score of back pain and sciatica were improved from 8.0 and 7.0 points to 3.4 and 2.4 during 1 years follow-up visit and the scores was raised gradually. Also, during the follow-up, 94% of patients showed excellent or good outcomes by the Odom's criteria. Intervertebral disc height was increased from 8.2±1.4mm to 9.2±1.9mm at the first year of follow-up, however, found to be decreased and stabilized to 8.3±1.8mm after 2 years. The fusion rate was approximately 91% after 4 year postoperative. The segmental angle of lordosis was increased significantly by two years but it was not maintained after four years. A statistically insignificant change in total lumbar lordosis was also observed. Three patients (9%) had experienced perioperative complications. Conclusion The use of rectangular stand-alone cages for posterior lumbar interbody fusion (PLIF) resulted in a various degree of subsidence and demonstrate very low complication rate, high functional stability and improved clinical outcomes in patients with degenerative lumbar disc disease. PMID:24757473

Cho, Kyung Rae; Lee, Sun-Ho; Kim, Eun Sang

2013-01-01

64

[The design, preparation and compressive strength testing of interbody fusion cages made from a composite of multi-amino acid copolymer/tri-calcium phosphate].  

PubMed

This research was to design and prepare interbody fusion cages using composite materials of multi-amino acid copolymer/tri-calcium phosphate (MAACP/TCP) and to test compressive strength of the cages. 16 specimens of C3-4 segments from female adult goats were scanned by X-ray to exclude disease of cervical spine, and then anatomical data were measured, i. e. disc space height of C3-4 segment (DSH), sagittal diameter of C3 lower endplate (SDLE3), sagittal diameter of C4 upper endplate (SDUE4), coronary diameter of C3 lower endplate (CDLE3), and coronary diameter of C4 upper endplate (CDUE4). According to the anatomical data, we designed and prepared the interbody fusion cage using the composite of MAACP/TCP and titanium with the same sizes. The MAACP/TCP Cages were made with the method of injection molding and finish machining, and titanium Cages were made with machining. In the testing of compressive strength of Cages, the specimens were divided into three groups, tricortical iliac crest bone group (isolated from goats), MAACP/TCP Cage group and titanium Cage group. There were 8 specimens in every group with the same sizes, the length of 12 mm, the width of 10 mm, and the height of 6 mm. The compressive strength of all specimens was tested on a universal testing machine. The values of DSH, SDLE3, SDUE4, CDLE3 and CDUE4 were (4.78 +/- 0.17) mm, (15.06 +/- 0.53) mm, (12.46 +/- 0.44) mm, (14.47 +/- 0.51) mm and (12.15 +/- 0.65) mm, respectively. MAACP/TCP Cage was successfully designed and made with a compressive strength of 76.34 MPa, which was much higher than that of tricortical iliac crest bone (18.41 MPa). The maximal loading of universal testing machine was 50 000 N, so the compressive strength of titanium Cages, whose value should be more than 541.35 MPa, could not be tested precisely. It is feasible to make cages with MAACP/TCP composite, and the compressive strength of MAACP/TCP Cages was much higher than that of tricortical iliac crest bone isolated from goats. PMID:22295701

Zhou, Chungnang; Song, Yueming; Tu, Chongqi; Pei, Fuxing; Duan, Hong; Liu, Limin; Li, Hong

2011-12-01

65

Effects of Lordotic Angle of a Cage on Sagittal Alignment and Clinical Outcome in One Level Posterior Lumbar Interbody Fusion with Pedicle Screw Fixation  

PubMed Central

This study aims to assess the differences in the radiological and clinical results depending on the lordotic angles of the cage in posterior lumbar interbody fusion (PLIF). We reviewed 185 segments which underwent PLIF using two different lordotic angles of 4° and 8° of a polyetheretherketone (PEEK) cage. The segmental lordosis and total lumbar lordosis of the 4° and 8° cage groups were compared preoperatively, as well as on the first postoperative day, 6th and 12th months postoperatively. Clinical assessment was performed using the ODI and the VAS of low back pain. The pre- and immediate postoperative segmental lordosis angles were 12.9° and 12.6° in the 4° group and 12° and 12.0° in the 8° group. Both groups exhibited no significant different segmental lordosis angle and total lumbar lordosis over period and time. However, the total lumbar lordosis significantly increased from six months postoperatively compared with the immediate postoperative day in the 8° group. The ODI and the VAS in both groups had no differences. Cages with different lordotic angles of 4° and 8° showed insignificant results clinically and radiologically in short-level PLIF surgery. Clinical improvements and sagittal alignment recovery were significantly observed in both groups.

Lee, Ji-Ho; Lee, Dong-Oh; Lee, Jae Hyup; Shim, Hee Jong

2015-01-01

66

Expert's comment concerning Grand Rounds case entitled "Minimal access bilateral transforaminal lumbar interbody fusion for high-grade isthmic spondylolisthesis" (by Nasir A. Quraishi and Y. Raja Rampersaud; doi:10.1007/s00586-012-2623-2).  

PubMed

This Expert's Comment discusses the Grand Rounds Case entitled "Minimal Access Bilateral Transforaminal Lumbar Interbody Fusion for High-Grade Isthmic Spondylolisthesis" by Nasir A Quraishi and Raja Y Rampersaud. It puts a technically elegant surgical method for minimally invasive reduction and arthrodesis of isthmic spondylolistheses into the context of short and long term outcomes and questions the motivations for performing such minimally invasive procedures in the absence of any proven mid or long term advantages over more traditional techniques. In addition, the use of BMP in spinal arthrodesis is discussed on the background of recently published IPD metaanalyses from the Infuse spinal FDA trials. PMID:23868222

Birkenmaier, Christof

2013-08-01

67

Four-year follow-up results of transforaminal lumbar interbody fusion as revision surgery for recurrent lumbar disc herniation after conventional discectomy.  

PubMed

This study investigated the safety, effectiveness, and clinical and radiological outcomes of transforaminal lumbar interbody fusion (TLIF) for recurrent lumbar disc herniation (rLDH) following previous lumbar spine surgery. Seventy-three consecutive patients treated for rLDH between June 2005 and May 2012 were included in the study. The previous surgical procedures included percutaneous discectomy, discectomy with laminotomy, discectomy with unilateral laminectomy, and discectomy with bilateral laminectomy. The level of rLDH was L4-L5 in 51 patients, L5-S1 in 19 patients, and L3-L4 in three patients. All patients underwent reoperation using the TLIF technique. Outcomes were evaluated using the Oswestry disability index (ODI), visual analogue scale (VAS) scores for low back pain and leg pain, and the Japanese Orthopaedic Association (JOA) score, based on the results of physical examinations and questionnaires. The range of motion and disc height index of the operative segment were compared between preoperative and postoperative radiographs. The mean follow-up period was 4.1years. The VAS scores for low back pain and leg pain, ODI, and JOA score improved significantly between the preoperative and final follow-up evaluations. The mean recovery rate of the JOA score was 89.0%. The disc space height and stability at the fused level were significantly improved after surgery. The fusion rate at the final follow-up was 93.2%. There were no major complications. These results indicate that TLIF can be considered an effective, reliable, and safe alternative procedure for the treatment of rLDH. PMID:25443080

Li, Zhonghai; Tang, Jiaguang; Hou, Shuxun; Ren, Dongfeng; Li, Li; Lu, Xiang; Hou, Tiesheng

2015-02-01

68

Evaluation of Functional Outcomes in Individuals 10 Years after Posterior Lumbar Interbody Fusion with Corundum Implants and Decompression: A Comparison of 2 Surgical Techniques  

PubMed Central

Background The purpose of this study was to evaluate lumbar spine-related functional disability in individuals 10 years after lumbar decompression and lumbar decompression with posterior lumbar interbody fusion (PLIF) with corundum implants surgery for degenerative stenosis and to compare the long-term outcome of these 2 surgical techniques. Material/Methods From 1998 to 2002, 100 patients with single-level lumbar stenosis were surgically treated. The patients were randomly divided into 2 groups that did not differ in terms of clinical or neurological symptoms. Group A consisted of 50 patients who were treated with PLIF and the use of porous ceramic corundum implants; the mean age was 57.74 and BMI was 27.34. Group B consisted of 50 patients treated with decompression by fenestration; mean age was 51.28 and the mean BMI was 28.84. Results There was no statistical significance regarding age, BMI, and sex. Both treatments revealed significant improvements. In group A, ODI decreased from 41.01% to 14.3% at 1 year and 16.3 at 10 years. In group B, ODI decreased from 63.8% to 18.36% at 1 year and 22.36% at 10 years. The difference between groups was statistically significant. There were no differences between the groups regarding the Rolland-Morris disability questionnaire and VAS at 1 and 10 years after surgery. Conclusions Long-term results evaluated according to the ODI, the Rolland-Morris disability questionnaire, and the VAS showed that the both methods significantly reduce patient disability, and this was maintained during next 10 years. The less invasive fenestration procedure was only slightly less favorable than surgical treatment of stenosis by both PLIF with corundum implants and decompression. PMID:25106708

Truszczy?ska, Aleksandra; R?pa?a, Kazimierz; ?ukawski, Stanislaw; Trzaskoma, Zbigniew; Tarnowski, Adam; Drzal-Grabiec, Justyna; Cabak, Anna

2014-01-01

69

K-Wire fracture during minimally invasive transforaminal lumbar interbody fusion: Report of six cases and recommendations for avoidance and management  

PubMed Central

Background: Although rare, minimally invasive spine techniques do have the risk of intraoperative device failure. Kirschner wire (K-wire) fractures during minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) have not been previously reported. This report focuses on the incidence of k-wire fractures following MI-TLIF and describes techniques to help avoid and treat these fractures when they occur. Methods: Inclusion criteria: (i) patients underwent 1, 2, or 3 level MI-TLIF over a 10-year period and (ii) had a k-wire fracture leading to a retained fragment. Exclusion criteria included: >10° coronal curves, significant sagittal malalignment, infection, and preoperative instrumentation failure. Results: Of 513 patients undergoing MI-TLIF, 6 (1.2%) sustained k-wire fracture (3 males, 3 females, mean age 43 ± 13 years). Complications included k-wire fracture alone (4 patients), cerebrospinal fluid (CSF) leak (1 patient), and both ileus and revision for hardware removal (1 patient). All six patients went home postoperatively. The mean follow-up duration was 27.7 ± 37.4 months. All retained k-wire fragments were located in the vertebral bodies at the tip of the pedicle screws; none breached the anterior cortex of the vertebral bodies. None of the k-wires migrated at final follow-up 7.8 years (93.7 months) postoperatively. Furthermore, no complications were attributed to retained k-wires. Conclusions: K-wire fractures during MI-TLIF are rare (incidence of 1.2%) and retained k-wire segments led to no postoperative complications (e.g. no migration). PMID:25593770

Scheer, Justin K.; Harvey, Michael J.; Dahdaleh, Nader S.; Smith, Zachary A.; Fessler, Richard G.

2014-01-01

70

The Significance of Removing Ruptured Intervertebral Discs for Interbody Fusion in Treating Thoracic or Lumbar Type B and C Spinal Injuries through a One-Stage Posterior Approach  

PubMed Central

Objectives To identify the negative effect on treatment results of reserving damaged intervertebral discs when treating type B and type C spinal fracture-dislocations through a one-stage posterior approach. Methods This is a retrospective review of 53 consecutive patients who were treated in our spine surgery center from January 2005 to May 2012 due to severe thoracolumbar spinal fracture-dislocation. The patients in Group A (24 patients) underwent long-segment instrumentation laminectomy with pedicle screw-rod fixators for neural decompression. In Group B (29 patients), the patients underwent long-segment instrumentation laminectomy with pedicle screw-rod fixators for neural decompression evacuating of the ruptured disc and inserting of a bone graft into the evacuated disc space for interbody fusion. The mean time between injury and operation was 4.1 days (range 2–15 days). The clinical, radiologic and complication outcomes were analyzed retrospectively. Results Periodic follow-ups were carried out until an affirmative union or treatment failure took place. A progressive kyphosis angle larger than 10°, loss of disc height, pseudoarthrosis, recurrence of dislocation or subluxation, or instrument failure before fusion were considered treatment failures. Treatment failures were detected in 13 cases in Group A (failure rate was 54.2%). In Group B, there were 28 cases in which definitive bone fusion was demonstrated on CT scans, and CT scans of the other cases demonstrated undefined pseudoarthrosis without hardware failure. There were statistically significant differences between the two groups (p<0.001 chi-square test). The neurologic recoveries, assessed by the ASIA scoring system, were not satisfactory for the neural deficit patients in either group, indicating there was no significant difference with regard to neurologic recovery between the two groups (p>0.05 Fisher's exact test). Conclusion Intervertebral disc damage is a common characteristic in type B and C spinal fracture-dislocation injuries. The damaged intervertebral disc should be removed and substituted with a bone graft because reserving the damaged disc in situ increases the risk of treatment failure. PMID:24827733

Zhang, Qian-Shi; Lü, Guo-Hua; Wang, Xiao-Bin; Li, Jing

2014-01-01

71

Spontaneous slip reduction of low-grade isthmic spondylolisthesis following circumferential release via bilateral minimally invasive transforaminal lumbar interbody fusion: technical note and short-term outcome.  

PubMed

STUDY DESIGN.: Retrospective clinical data analysis. OBJECTIVE.: To investigate and verify our philosophy of spontaneous slip reduction following circumferential release via bilateral minimally invasive transforaminal lumbar interbody fusion (Mini-TLIF) for treatment of low-grade symptomatic isthmic spondylolisthesis. SUMMARY OF BACKGROUND DATA.: Symptomatic isthmic spondylolisthesis usually requires surgical intervention, and the most currently controversial focus is on method and degree of reduction; and Mini-TLIF is an attractive surgical procedure for isthmic spondylolisthesis. METHODS.: Between February 2004 and June 2008, 21 patients with low-grade isthmic spondylolisthesis underwent Mini-TLIF in our institute. Total resection of the scar around the pars interarticularis liberated the nerve roots, achieving posterior release as well. The disc was thoroughly resected, and the disc space was gradually distracted and thoroughly released with sequential disc shavers until rupture of anulus conjunct with anterior longitudinal ligament, accomplishing anterior release, so as to insert Cages. Because of circumferential release, the slipped vertebrae would tend to obtain spontaneous reduction, and with pedicle screw fixation, additional reduction would be achieved without any application of posterior translation force. Radiographs, Visual Analogue Scale, and Oswestry Disability Index were documented. All the cases were followed up for 10 to 26 months. RESULTS.: Slip percentage was reduced from 24.2% ± 6.9% to 10.5% ± 4.0%, and foraminal area percentage increased from 89.1% ± 3.0% to 93.6% ± 2.1%. Visual Analogue Scale and Oswestry Disability Index decreased from 7.8 ± 1.5 to 2.1 ± 1.1 and from 53.3 ± 16.2 to 17.0 ± 7.8, respectively. No neurologic complications were encountered. There were no signs of instrumentation failure. The fusion rate approached 100%. CONCLUSION.: Slip reduction is based on circumferential release. The procedure can be well performed via Mini-TLIF, the outcome of which is equally gratifying to that of instrumented slip reduction and traditional midline approach. There is no need to fully reduce the slipped vertebrae. Circumferential release contributes to achieving spontaneous slip reduction partially, which aids sufficiently in the surgical treatment of low-grade isthmic spondylolisthesis. PMID:20714277

Pan, Jie; Li, Lijun; Qian, Lie; Zhou, Wei; Tan, Jun; Zou, Le; Yang, Mingjie

2011-02-15

72

The CASCADE trial: effectiveness of ceramic versus PEEK cages for anterior cervical discectomy with interbody fusion; protocol of a blinded randomized controlled trial  

PubMed Central

Background Anterior cervical discectomy with interbody fusion cages is considered the standard surgical procedure in patients with cervical disc herniation. However, PEEK or metal cages have some undesirable imaging characteristics, leading to a search for alternative materials not creating artifacts on images; silicon nitride ceramic. Whether patients treated with silicon nitride ceramic cages have similar functional outcome as patients treated with PEEK cages is not known. We present the design of the CASCADE trial on effectiveness of ceramic cages versus PEEK cages in patients with cervical disc herniation and/or osteophytes. Methods/Design Patients (age 18–75 years) with monoradicular symptoms in one or both arms lasting more than 8 weeks, due to disc herniation and/or osteophytes, are eligible for the trial. The study is designed as a randomized controlled equivalence trial in which patients are blinded to the type of cage for 1 year. The total follow-up period is 2 years. The primary outcome measure is improvement in the Neck and Disability Index (NDI). Secondary outcomes measures include improvement in arm pain and neck pain (VAS), SF-36 and patients' perceived recovery. The final elements of comparison are perioperative statistics including operating time, blood loss, length of hospital stay, and adverse events. Lateral plane films at each follow-up visit and CT scan (at 6 months) will be used to judge fusion and the incidence of subsidence. Based on a power of 90% and assuming 8% loss to follow-up, 100 patients will be randomized into the 2 groups. The first analysis will be conducted when all patients have 1 year of follow-up, and the groups will be followed for 1 additional year to judge stability of outcomes. Discussion While the new ceramic cage has received the CE Mark based on standard compliance and animal studies, a randomized comparative study with the golden standard product will provide more conclusive information for clinicians. Implementation of any new device should only be done after completion of randomized controlled effectiveness trials. PMID:23947902

2013-01-01

73

A Comparison of Radiostereometric Analysis and Computed Tomography for the Assessment of Lumbar Spinal Fusion in a Sheep Model  

PubMed Central

Study Design?Prospective animal study. Objective?The aim of this animal study is to evaluate the accuracy of radiostereometric analysis (RSA) compared with computed tomographic (CT) scan in the assessment of spinal fusion after anterior lumbar interbody fusion (ALIF) using histology as a gold standard. Methods?Three non-adjacent ALIFs (L1–L2, L3–L4, and L5–L6) were performed in nine sheep. The sheep were divided into three groups of three sheep. All the animals were humanely killed immediately after having the last scheduled RSA. The lumbar spine was removed and in vitro fine cut CT and histopathology were performed. Results?Using histological assessment as the gold standard for assessing fusion, RSA demonstrated better results (100% sensitivity and 66.7% specificity; positive predictive value [PPV]?=?27.3%, negative predictive value [NPV] =100.0%) compared with CT (66.7% sensitivity and 60.0% specificity [PPV?=?16.7%, NPV?=?93.8%]). Conclusions?RSA demonstrated higher sensitivity and specificity when compared with CT. Furthermore, RSA has the advantage of much lower radiation exposure compared with fine cut CT. Further studies are required to see if RSA remains superior to CT scan for the assessment spinal fusion in the clinical setting. Assessment of Class of Evidence (CoE) for individual studies of diagnostic test evaluation Methodological principle Study design  Prospective cohort design X  Retrospective cohort design  Case–control design Broad spectrum of patients with expected condition a Appropriate reference standard used X Adequate description of test and reference for replication X Blinded comparison with appropriate reference X Reference standard performed independently of test X Evidence level II Note: Blank box indicates criterion not met, could not be determined, or information not reported by author or was not reported. aThis study contained nine animal subjects. PMID:24436705

Humadi, Ali; Freeman, Brian J. C.; Moore, Rob J.; Callary, Stuart; Halldin, Klas; David, Vikram; Maclaurin, William; Tauro, Paul; Schoenwaelder, Mark

2013-01-01

74

Biomechanics of Lateral Interbody Spacers: Going Wider for Going Stiffer  

PubMed Central

This study investigates the biomechanical stability of a large interbody spacer inserted by a lateral approach and compares the biomechanical differences with the more conventional transforaminal interbody fusion (TLIF), with and without supplemental pedicle screw (PS) fixation. Twenty-four L2-L3 functional spinal units (FSUs) were tested with three interbody cage options: (i) 18?mm XLIF cage, (ii) 26?mm XLIF cage, and (iii) 11?mm TLIF cage. Each spacer was tested without supplemental fixation, and with unilateral and bilateral PS fixation. Specimens were subjected to multidirectional nondestructive flexibility tests to 7.5?N·m. The range of motion (ROM) differences were first examined within the same group (per cage) using repeated-measures ANOVA, and then compared between cage groups. The 26?mm XLIF cage provided greater stability than the 18?mm XLIF cage with unilateral PS and 11?mm TLIF cage with bilateral PS. The 18?mm XLIF cage with unilateral PS provided greater stability than the 11?mm TLIF cage with bilateral PS. This study suggests that wider lateral spacers are biomechanically stable and offer the option to be used with less or even no supplemental fixation for interbody lumbar fusion. PMID:23213284

Pimenta, Luiz; Turner, Alexander W. L.; Dooley, Zachary A.; Parikh, Rachit D.; Peterson, Mark D.

2012-01-01

75

ISASS Policy Statement - Cervical Interbody  

PubMed Central

Morgan Lorio, MD, FACS, Chair, ISASS Task Force on Coding & Reimbursement In 2011, CPT code 22551 was revised to combine or bundle CPT codes 63075 and 22554 when both procedures were performed at the same site/same surgical session. The add on code +22552 is used to report each additional interspace. 2014 heralded a downward pressure on this now prime target code (for non-coverage?) 22551 through an egregious insurer attempt to redefine cervical arthrodesis, effectively removing spine surgeon choice and altering best practice without clinical evidence. Currently, spine surgeons are equally split on the use of allograft versus cages for cervical arthrodesis. Structural allograft, CPT code 20931, is reported once per same surgical session, regardless of the number of allografts used. CPT code 22851 which is designated solely for cage use, has a higher reimbursement than structural allograft, and may be reported for each inner space. Hence, the rationale behind why some payers wrongly consider “spine cages NOT medically necessary for cervical fusion.” A timely consensus paper summarizing spine surgeon purview on the logical progressive evolution of cervical interbody fusion for ISASS/IASP membership was strategically identified as an advocacy focus by the ISASS Task Force. ISASS appreciates the authors’ charge with gratitude. This article has both teeth and transparent clinical real-world merit.

Singh, Kern; Qureshi, Sheeraz

2014-01-01

76

Comparison between Two Different Cervical Interbody Fusion Cages in One Level Stand-alone ACDF: Carbon Fiber Composite Frame Cage Versus Polyetheretherketone Cage  

PubMed Central

Objective The authors conducted a retrospective study to compare the implantation of carbon fiber composite frame cages (CFCFCs) to the implantation of polyetheretherketone (PEEK) cages after anterior cervical discectomy for cervical degenerative disc disease. In addition, the predictive factors that influenced fusion or subsidence were investigated. Methods A total of 58 patients with single-level degenerative disc disease were treated with anterior cervical discectomy and implantation of stand-alone cages; CFCFCs were used in 35 patients, and PEEK cages were used in 23 patients. Preoperative and postoperative radiological and clinical assessments were performed. Results During the mean follow-up period of 41 months, fusion occurred in 43 patients (74.1%), and subsidence developed in 18 patients (31.0%). Pain decreased in all patients, and the patients' satisfaction rate was 75.9%. Neither fusion nor subsidence was related to the clinical outcome. There were no significant differences in the clinical and radiological outcomes between the CFCFC and the PEEK cage groups. Smoking history (p=0.023) was significantly associated with pseudarthrosis, and cage height (?7mm) (p=0.037) were significantly associated with subsidence. Conclusion The clinical and radiological results were similar between the CFCFC and the PEEK cage groups. Fusion or subsidence did not affect the clinical outcomes. Smoking history and cage height (?7mm) were predictive factors for pseudarthrosis or subsidence in anterior cervical discectomy and fusion with stand-alone cages. PMID:25346758

Yoo, Minwook; Kim, Wook-Ha; Hyun, Seung-Jae; Jahng, Tae-Ahn; Kim, Hyun-Jib

2014-01-01

77

Spine interbody implants: material selection and modification, functionalization and bioactivation of surfaces to improve osseointegration.  

PubMed

The clinical outcome of lumbar spinal fusion is correlated with achievement of bony fusion. Improving interbody implant bone on-growth and in-growth may enhance fusion, limiting pseudoarthrosis, stress shielding, subsidence and implant failure. Polyetheretherketone (PEEK) and titanium (Ti) are commonly selected for interbody spacer construction. Although these materials have desirable biocompatibility and mechanical properties, they require further modification to support osseointegration. Reports of extensive research on this topic are available in biomaterial-centric published reports; however, there are few clinical studies concerning surface modification of interbody spinal implants. The current article focuses on surface modifications aimed at fostering osseointegration from a clinician's point of view. Surface modification of Ti by creating rougher surfaces, modifying its surface topography (macro and nano), physical and chemical treatment and creating a porous material with high interconnectivity can improve its osseointegrative potential and bioactivity. Coating the surface with osteoconductive materials like hydroxyapatite (HA) can improve osseointegration. Because PEEK spacers are relatively inert, creating a composite by adding Ti or osteoconductive materials like HA can improve osseointegration. In addition, PEEK may be coated with Ti, effectively bio-activating the coating. PMID:24890288

Rao, Prashanth J; Pelletier, Matthew H; Walsh, William R; Mobbs, Ralph J

2014-05-01

78

Lumbar Laminectomy and Transforaminal Lumbar Interbody Fusion  

MedlinePLUS Videos and Cool Tools

... precursor molecule to making bone. It derives the cells, it brings the cells from the tissues and the blood to the ... analogous process to healing of a fracture, where cells will come into the area, blood cells, basic ...

79

A-life, Organism and Body: the semiotics of emergent levels Claus Emmeche1  

E-print Network

117 A-life, Organism and Body: the semiotics of emergent levels Claus Emmeche1 1 Center This paper comments upon some of the open problems in ar- tificial life (cf. Bedeau et al 2000) from the emerging field of biosemio- tics, the study of life processes as sign processes. Semiotics, in the sense

Emmeche, Claus

80

ALife-WebGuide: An Intelligent User Interface for Web Site Navigation  

E-print Network

Guide, an intelligent software bot that helps users navigate a Web site using natural language. The article describes site interface, Web navigation, intelligent navigation, software bots, natural language. 1ALife-WebGuide: An Intelligent User Interface for Web Site Navigation Paolo Gaudiano Artificial

81

IKI-IKI phone: a multi-user alife art game for mobile phones  

Microsoft Academic Search

IKI-IKI Phone is a multi-user, networked Artificial Life (= Alife) art game for the I-mode mobile phones. In this system, subscribed users can create Artificial Life creatures (= IKI-IKI pets), interact with these pets, feed them, take care of them, and evolve them. Networked users can also share their pets with other mobile phones users, trade them, watch them compete

Christa Sommerer; Laurent Mignonneau; Roberto Lopez-Gulliver

2001-01-01

82

Construct Rigidity after Fatigue Loading in Pedicle Subtraction Osteotomy with or without Adjacent Interbody Structural Cages  

PubMed Central

Introduction?Studies document rod fracture in pedicle subtraction osteotomy (PSO) settings where disk spaces were preserved above or adjacent to the PSO. This study compares the multidirectional bending rigidity and fatigue life of PSO segments with or without interbody support. Methods?Twelve specimens received bilateral T12–S1 posterior fixation and L3 PSO. Six received extreme lateral interbody fusion (XLIF) cages in addition to PSO at L2–L3 and L3–L4; six had PSO only. Flexion-extension, lateral bending, and axial rotation (AR) tests were conducted up to 7.5 Newton-meters (Nm) for groups: (1) posterior fixation, (2) L3 PSO, (3) addition of cages (six specimens). Relative motion across the osteotomy (L2–L4) and entire fixation site (T12–S1) was measured. All specimens were then fatigue tested for 35K cycles. Results?Regardingmultiaxial bending, there was a significant 25.7% reduction in AR range of motion across L2–L4 following addition of cages. Regarding fatigue bending, dynamic stiffness, though not significant (p?=?0.095), was 22.2% greater in the PSO?+?XLIF group than in the PSO-only group. Conclusions?Results suggest that placement of interbody cages in PSO settings has a potential stabilizing effect, which is modestly evident in the acute setting. Inserting cages in a second-stage surgery remains a viable option and may benefit patients in terms of recovery but additional clinical studies are necessary to confirm this. PMID:24353970

Deviren, Vedat; Tang, Jessica A.; Scheer, Justin K.; Buckley, Jenni M.; Pekmezci, Murat; McClellan, R. Trigg; Ames, Christopher P.

2012-01-01

83

Instrumentation in lumbar fusion improves back pain but not quality of life 2 years after surgery  

PubMed Central

Background and purpose Instrumented and non-instrumented methods of fusion have been compared in several studies, but the results are often inconsistent and conflicting. We compared the 2-year results of 3 methods of lumbar fusion when used in degenerative disc disease (DDD), using the Swedish Spine Register (SWESPINE). Methods All patients registered in SWESPINE for surgical treatment of DDD between January 1, 2000 and October 1, 2007 were eligible for the study. Patients who had completed the 2-year follow-up were included in the analysis. The outcomes of 3 methods of surgical fusion were assessed. Results Of 1,310 patients enrolled, 115 had undergone uninstrumented fusion, 620 instrumented posterolateral fusion, and 575 instrumented interbody fusion. Irrespective of the surgical procedure, quality of life (QoL) improved and back pain diminished. Change in QoL and functional disability and return to work was similar in the 3 groups. Patients who had undergone uninstrumented fusion had more back pain than the patients with instrumented interbody fusion at the 2-year follow-up (p = 0.02), although the difference was only 7 visual analog scale (VAS) units (95% CI: 1–13) on a 100-point scale. Moreover, 83% of the patients with uninstrumented fusion used analgesics at the end of follow-up as compared to 68% of the patients who had undergone surgery with one of the 2 instrumented fusion techniques. Interpretation In comparison with instrumented interbody fusion, uninstrumented fusion was associated with higher levels of back pain 2 years after surgery. We found no evidence for differences in QoL between uninstrumented fusion and instrumented interbody fusion. PMID:23368746

2013-01-01

84

Spinal fusion  

MedlinePLUS

... Anterior spinal fusion; Spine surgery - spinal fusion; Low back pain - fusion; Herniated disk - fusion ... If you had chronic back pain before surgery, you will likely still have some pain afterward. Spinal fusion is unlikely to take away all your pain ...

85

Anterior cervical interbody constructs: effect of a repetitive compressive force on the endplate.  

PubMed

Graft subsidence following anterior cervical reconstruction can result in the loss of sagittal balance and recurring foraminal stenosis. This study examined the implant-endplate interface using a cyclic fatigue loading protocol in an attempt to model the subsidence seen in vivo. The superior endplate from 30 cervical vertebrae (C3 to T1) were harvested and biomechanically tested in axial compression with one of three implants: Fibular allograft; titanium mesh cage packed with cancellous chips; and trabecular metal. Each construct was cyclically loaded from 50 to 250?N for 10,000 cycles. Nondestructive cyclic loading of the cervical endplate-implant construct resulted in a stiffer construct independent of the type of the interbody implant tested. The trabecular metal construct demonstrated significantly more axial stability and significantly less subsidence in comparison to the titanium mesh construct. Although the allograft construct resulted in more subsidence than the trabecular metal construct, the difference was not significant and no difference was found when comparing axial stability. For all constructs, the majority of the subsidence during the cyclic testing occurred during the first 500 cycles and was followed by a more gradual settling in the remaining 9,500 cycles. PMID:22002745

Ordway, Nathaniel R; Rim, Byeong Cheol; Tan, Rong; Hickman, Rebecca; Fayyazi, Amir H

2012-04-01

86

Pullout of a lumbar plate with varying screw lengths  

PubMed Central

Background Screw length pertains to stability in various orthopedic fixation devices. There is little or no information on the relationship between plate pullout strength and screw length in anterior lumbar interbody fusion (ALIF) plate constructs in the literature. Such a description may prove useful, especially in the treatment of osteoporotic patients where maximizing construct stability is of utmost importance. Our purpose is to describe the influence of screw length on ALIF plate stability in severely and mildly osteoporotic bone foam models. Methods Testing was performed on polyurethane foam blocks with densities of 0.08 g/cm3 and 0.16 g/cm3. Four-screw, single-level ALIF plate constructs were secured to the polyurethane foam blocks by use of sets of self-tapping cancellous bone screws that were 20, 24, 28, 32, and 36 mm in length and 6.0 mm in diameter. Plates were pulled out at 1 mm/min to failure, as defined by consistently decreasing load despite increasing displacement. Results Pullout loads in 0.08-g/cm3 foam for 20-, 24-, 28-, 32-, and 36-mm screws averaged 303, 388, 479, 586, and 708 N, respectively, increasing at a mean of 25.2 N/mm. In 0.16-g/cm3 foam, pullout loads for 20-, 24-, 28-, 32-, and 36-mm screws averaged 1004, 1335, 1569, 1907, and 2162 N, respectively, increasing at a mean of 72.2 N/mm. Conclusions The use of longer screws in ALIF plate installation is expected to increase construct stability. Stabilization from screw length in osteoporotic patients, however, is limited.

Palmer, Daniel Kyle; Rios, David; Patacxil, Wyzscx Merfil; Williams, Paul A.; Cheng, Wayne K.; ?nceo?lu, Serkan

2012-01-01

87

Single level Lumbar Fusion for Degenerative Disc Disease is Associated with Worse outcomes compared to Fusion for Spondylolisthesis in a Workers' Compensation Setting.  

PubMed

Study Design. Retrospective cohort studyObjective. Compare lumbar fusion outcomes, return to work (RTW) status in particular, between workers' compensation (WC) subjects undergoing single level posterolateral fusion for either spondylolisthesis or degenerative disc disease (DDD)Summary of Background Data. Lumbar fusion for spondylolisthesis tends to yield more consistent outcomes than fusion for DDD and discogenic low back pain. Within the clinically distinct WC population, relatively few studies exist which evaluate lumbar fusion outcomes.Methods. 869 Ohio WC subjects were identified that underwent single level posterolateral lumbar fusion with or without posterior interbody fusion between 1993-2010 using CPT procedural and ICD-9 diagnostic codes. 269 underwent fusion for spondylolisthesis, and 620 of underwent fusion for DDD.Subjects were considered returned to work within a reasonable timeline if they made a stable RTW within 2 years of fusion and remained working for greater than 6 months of the following year. To determine predictors of RTW status, we performed a multivariate logistic regression analysis. We measured a number of secondary outcomes.Results. Fusion for spondylolisthesis was positively associated with RTW status (p = 0.050; OR 1.42,CI 1.00-2.00). 36.4% of the spondylolisthesis cohort and 24.4% of the DDD cohort returned to work in a reasonable timeline postoperatively.Other negative predictors included: age >50 at fusion (OR 0.66,CI 0.45-0.95), >2 years between injury and index fusion (OR 0.59,CI 0.41-0.84), permanent disability (OR 0.61,CI 0.43-0.86), legal representation (OR 0.67,CI 0.46-0.97), and psychological comorbidity before fusion (OR 0.30,CI 0.14-0.62).Subjects in the DDD cohort were prescribed opioid analgesics for an average of 294 of additional days postoperatively (p<0.001), which equated to 24,759 additional milligrams of morphine equivalents (p<0.001).Conclusions. Our study is supportive of the conclusion that DDD is a questionable indication for spinal fusion. Given the generally poor outcomes of this study, future studies should determine if lumbar fusion surgery is an effective treatment modality in similar WC patients. PMID:25494321

Anderson, Joshua T; Haas, Arnold R; Percy, Rick; Woods, Stephen T; Ahn, Uri M; Ahn, Nicholas U

2014-12-01

88

Changes in Neuroforaminal Height with 2 Level Axial Presacral Lumbar Interbody Fusion at L4-S1  

PubMed Central

Background The objective was to examine the changes in neuroforaminal height at L4-L5 and L5-S1 after insertion and graduated foraminal distraction using the 2 level transsacral implant in a cadaveric model. Methods Discectomy and transsacral instrumentation was performed in six fresh human cadavers at L4-S1. The neuroforaminal height was measured at L4-L5 and L5-S1 before and after insertion of the implant and then at each stage of manual distraction. Results Mean L4-5 neuroforaminal height increased from 18.2 ± 3.1mm to 20.3± 2.9mm (11%) on the left and from 18.8±2.8mm to 20.6± 2.3mm (12%) on the right (P<0.05). Mean L5-S1 neuroforaminal height increased from 15.7±3.0mm to 18.4 ±2.8mm (17%) on the left and from 15.6 ±2.1mm to 18.3 ±1.8mm (17%) on the right (P<0.05). When the neuroforaminal height was plotted against amount of rotation of the screw driver it was found that the neuroforaminal height at L5-S1 increased by 1mm on average for every complete revolution of the screw driver. At least 2 full rotations of the screw driver were achieved in all cadavers. Conclusions The transsacral screw construct distracted the disc space and neuroforaminal height in a cadaveric spine model without soft tissue envelope. During the initial process, manual control of disc space distraction predictably correlated with the increase in the neuroforaminal height to a maximum. However, further research is needed to look at variables affecting disc space pliability, implant subsidence, in vivo application, and clinical benefit of this procedure.

Marawar, Satyajit; Jung, Jin; Sun, Mike

2014-01-01

89

Guideline update for the performance of fusion procedures for degenerative disease of the lumbar spine. Part 16: bone graft extenders and substitutes as an adjunct for lumbar fusion.  

PubMed

In an attempt to enhance the potential to achieve a solid arthrodesis and avoid the morbidity of harvesting autologous iliac crest bone (AICB) for a lumbar fusion, numerous alternatives have been investigated. The use of these fusion adjuncts has become routine despite a lack of convincing evidence demonstrating a benefit to justify added costs or potential harm. Potential alternatives to AICB include locally harvested autograft, calcium-phosphate salts, demineralized bone matrix (DBM), and the family of bone morphogenetic proteins (BMPs). In particular, no option has created greater controversy than the BMPs. A significant increase in the number of publications, particularly with respect to the BMPs, has taken place since the release of the original guidelines. Both DBM and the calciumphosphate salts have demonstrated efficacy as a graft extender or as a substitute for AICB when combined with local autograft. The use of recombinant human BMP-2 (rhBMP-2) as a substitute for AICB, when performing an interbody lumbar fusion, is considered an option since similar outcomes have been observed; however, the potential for heterotopic bone formation is a concern. The use of rhBMP-2, when combined with calcium phosphates, as a substitute for AICB, or as an extender, when used with local autograft or AICB, is also considered an option as similar fusion rates and clinical outcomes have been observed. Surgeons electing to use BMPs should be aware of a growing body of literature demonstrating unique complications associated with the use of BMPs. PMID:24980593

Kaiser, Michael G; Groff, Michael W; Watters, William C; Ghogawala, Zoher; Mummaneni, Praveen V; Dailey, Andrew T; Choudhri, Tanvir F; Eck, Jason C; Sharan, Alok; Wang, Jeffrey C; Dhall, Sanjay S; Resnick, Daniel K

2014-07-01

90

Fusion breeder  

SciTech Connect

The fusion breeder is a fusion reactor designed with special blankets to maximize the transmutation by 14 MeV neutrons of uranium-238 to plutonium or thorium to uranium-233 for use as a fuel for fission reactors. Breeding fissile fuels has not been a goal of the US fusion energy program. This paper suggests it is time for a policy change to make the fusion breeder a goal of the US fusion program and the US nuclear energy program. The purpose of this paper is to suggest this policy change be made and tell why it should be made, and to outline specific research and development goals so that the fusion breeder will be developed in time to meet fissile fuel needs.

Moir, R.W.

1982-04-20

91

"Polarized" Fusion  

NASA Astrophysics Data System (ADS)

Increasing energy demand in view of limited supply, as well as environmental and nuclear-safety concerns leading to increased emphasis on renewable energy sources such as solar or wind energy are expected to focus public and scientific interest increasingly also on fusion energy. With the decision to build ITER (low-density magnetic confinement) and also continuing research on (high-density) inertial-confinement fusion (cf. the inauguration of the laser fusion facility at the Lawrence Livermore National Laboratory) prospects of fusion energy have probably entered a new era.

Schieck, Hans Paetz Gen.

92

Anterior Cervical Discectomy and Fusion Using a Stand-Alone Polyetheretherketone Cage Packed with Local Autobone : Assessment of Bone Fusion and Subsidence  

PubMed Central

Objective It remains debatable whether cervical spine fusion cages should be filled with any kind of bone or bone substitute. Cortical and subcortical bone from the anterior and posterior osteophytes of the segment could be used to fill the cage. The purposes of the present study are to evaluate the clinical outcomes and radiological outcomes including bone fusion and subsidence that occurred after anterior cervical discectomy and fusion using a stand-alone cage packed with local autobone graft. Methods Thirty-one patients who underwent anterior cervical fusion using a stand-alone polyetheretherketone (PEEK) cage packed with local autobone graft from July 2009 to december 2011 were enrolled in this study. Bone fusion was assessed by cervical plain radiographs and computed tomographic scan. Nonunion was evaluated according to the absence of bony bridge on computed tomographic scan. Subsidence was defined as a ?2 mm decrease of the interbody height at the final follow-up compared to that measured at the immediate postoperative period. Results Subsidence was observed in 7 patients (22.6%). Of 7 patients with subsidence greater 2 mm, nonunion was developed in 3. Three patients with subsidence greater 2 mm were related with endplate damage during intraoperative endplate preparation. Solid bone fusion was achieved in 28 out of 31 patients (90.3%). Conclusion With proper patient selection and careful endplate preparation, anterior cervical discectomy and fusion (ACDF) using a stand-alone PEEK cage packed with local autobone graft could be a good alternative to the standard ACDF techniques with plating. PMID:24278646

Park, Jeong-Ill; Kim, Kyoung-Tae; Sung, Joo-Kyung

2013-01-01

93

Assisted fusion  

E-print Network

A model of nuclear fusion consisting of a wave packet impinging into a well located between square one dimensional barriers is treated analytically. The wave function inside the well is calculated exactly for the assisted tunneling induced by a perturbation mimicking a constant electric field with arbitrary time dependence. Conditions are found for the enhancement of fusion.

German Kälbermann

2009-10-19

94

Image fusion  

NASA Technical Reports Server (NTRS)

The topics covered include the following: a system overview of the basic components of a system designed to improve the ability of a pilot to fly through low-visibility conditions such as fog; the role of visual sciences; fusion issues; sensor characterization; sources of information; image processing; and image fusion.

Pavel, M.

1993-01-01

95

Characteristics of Back Muscle Strength in Patients with Scheduled for Lumbar Fusion Surgery due to Symptomatic Lumbar Degenerative Diseases  

PubMed Central

Study Design Cross sectional study. Purpose To evaluate characteristics of back muscle strength in patients scheduled for lumbar fusion surgery. Overview of Literature Little is known regarding muscle strength in patients with symptomatic lumbar degenerative diseases who require fusion surgery. Methods Consecutive 354 patients scheduled for posterior lumbar interbody fusion due to symptomatic degenerative diseases were approached for participation. 316 patients were enrolled. Before surgery, muscle strength was assessed by measuring maximal isometric extension strength at seven angular positions (0°, 12°, 24°, 36°, 48°, 60°, and 72°) and mean isometric strength was calculated. The Oswestry Disability Index (0-100) and visual analogue scale (0-100) for back pain were recorded. Muscle strength was compared according to gender, age (<60, 60-70, and ?70 years) and scheduled fusion level (short, <3; long, ?3). Results Isometric strength was significantly decreased compared with previously reported results of healthy individuals, particularly at extension positions (0°-48°, p<0.05). Mean isometric strength was significantly lower in females (p<0.001) and older patients (p<0.05). Differences of isometric strength between short and long level fusion were not significantly different (p>0.05). Isometric strengths showed significant, but weak, inverse correlations with age and Oswestry Disability Index (r<0.4, p<0.05). Conclusions In patients with symptomatic lumbar degenerative diseases, back muscle strength significantly decreased, particularly at lumbar extension positions, and in females and older patients. PMID:25346820

Park, Won Hah; Lee, Chong Suh; Kang, Kyung Chung

2014-01-01

96

Durotomy is associated with pseudoarthrosis following lumbar fusion.  

PubMed

Pseudoarthrosis is a known complication following lumbar fusion, and although several risk factors have been established, the association of durotomy and pseudoarthrosis has not been studied to our knowledge. A retrospective review was performed to identify all adult patients who underwent lumbar posterolateral fusion (without interbody fusion) for degenerative spine disease over a 20year period at a single institution. Patients were divided into durotomy and no durotomy cohorts. Patients were included if they had at least 1year of follow-up. The main outcome variable was development of pseudoarthrosis. A total of 327 patients were identified, of whom 17 (5.19%) had a durotomy. Pseudoarthrosis rates were significantly higher in the durotomy group (35.29%) when compared to the no durotomy group (13.87%), with the difference being statistically significant (p=0.016). Univariate analysis revealed that durotomy (p=0.003) and the number of levels fused (p=0.015) were the only two significant risk factors for pseudoarthrosis. After controlling for the number of levels fused, the adjusted relative risk (RR) revealed that patients with a durotomy were 2.23 times more likely to develop pseudoarthrosis (RR 2.23; 95% confidence interval 1.05-4.75) when compared to patients without durotomy. The findings in the present study suggest an association between durotomy and pseudoarthrosis development. Patients with a durotomy were 2.2 times more likely to develop pseudoarthrosis compared to patients without a durotomy. Future and larger studies are required to corroborate our findings. PMID:25532509

Bydon, Mohamad; De la Garza-Ramos, Rafael; Abt, Nicholas B; Macki, Mohamed; Sciubba, Daniel M; Wolinsky, Jean-Paul; Bydon, Ali; Gokaslan, Ziya L; Witham, Timothy F

2015-03-01

97

RSNA 2002: Image Fusion Image Fusion  

E-print Network

RSNA 2002: Image Fusion Image Fusion: Introduction to the Technology Charles A. Pelizzari, Ph.D. Department of Radiation and Cellular Oncology The University of Chicago #12;RSNA 2002: Image Fusion "Fusion and limitations) ·Where do we need to go? (future directions) #12;RSNA 2002: Image Fusion Terminology

Pelizzari, Charles A.

98

Current strategies for the restoration of adequate lordosis during lumbar fusion  

PubMed Central

Not restoring the adequate lumbar lordosis during lumbar fusion surgery may result in mechanical low back pain, sagittal unbalance and adjacent segment degeneration. The objective of this work is to describe the current strategies and concepts for restoration of adequate lordosis during fusion surgery. Theoretical lordosis can be evaluated from the measurement of the pelvic incidence and from the analysis of spatial organization of the lumbar spine with 2/3 of the lordosis given by the L4-S1 segment and 85% by the L3-S1 segment. Technical aspects involve patient positioning on the operating table, release maneuvers, type of instrumentation used (rod, screw-rod connection, interbody cages), surgical sequence and the overall surgical strategy. Spinal osteotomies may be required in case of fixed kyphotic spine. AP combined surgery is particularly efficient in restoring lordosis at L5-S1 level and should be recommended. Finally, not one but several strategies may be used to achieve the need for restoration of adequate lordosis during fusion surgery. PMID:25621216

Barrey, Cédric; Darnis, Alice

2015-01-01

99

Current strategies for the restoration of adequate lordosis during lumbar fusion.  

PubMed

Not restoring the adequate lumbar lordosis during lumbar fusion surgery may result in mechanical low back pain, sagittal unbalance and adjacent segment degeneration. The objective of this work is to describe the current strategies and concepts for restoration of adequate lordosis during fusion surgery. Theoretical lordosis can be evaluated from the measurement of the pelvic incidence and from the analysis of spatial organization of the lumbar spine with 2/3 of the lordosis given by the L4-S1 segment and 85% by the L3-S1 segment. Technical aspects involve patient positioning on the operating table, release maneuvers, type of instrumentation used (rod, screw-rod connection, interbody cages), surgical sequence and the overall surgical strategy. Spinal osteotomies may be required in case of fixed kyphotic spine. AP combined surgery is particularly efficient in restoring lordosis at L5-S1 level and should be recommended. Finally, not one but several strategies may be used to achieve the need for restoration of adequate lordosis during fusion surgery. PMID:25621216

Barrey, Cédric; Darnis, Alice

2015-01-18

100

Anterior Extrusion of Fusion Cage in Posttraumatic Cervical Disk Disease.  

PubMed

Anterior interbody fusion of the cervical spine (ACDF) with bone grafts or cages has become the gold standard for treating cervical disk disease. Several technical modifications have been developed, but currently no consensus exists regarding the optimal technique. In addition, there is also evidence that complications are frequently associated with this procedure. A frequent cause for implant failure in monosegmental ACDF is cage migration into the vertebral end plates or the spinal canal. We report a patient admitted for sudden quadriparesis with complete motor deficit caused by posttraumatic cervical disk protrusion at C4-C5, resulting in spinal compression. ACDF using a titanium stand-alone cage was performed and cured the patient. At the 1-year follow-up visit, imaging showed asymptomatic anterior complete extrusion of the cage out of the disk space. To our knowledge, such an anterior cage migration without trauma has not been reported in the literature to date, and we tried to find technical reasons to explain this complication. PMID:25306206

Amelot, Aymeric; Bouazza, Schahrazed; George, Bernard; Orabi, Mikael; Bresson, Damien

2014-10-12

101

Laser fusion  

SciTech Connect

Unrestricted laser fusion offers nations an opportunity to circumvent arms control agreements and develop thermonuclear weapons. Early laser weapons research sought a clean radiation-free bomb to replace the fission bomb, but this was deceptive because a fission bomb was needed to trigger the fusion reaction and additional radioactivity was induced by generating fast neutrons. As laser-implosion experiments focused on weapons physics, simulating weapons effects, and applications for new weapons, the military interest shifted from developing a laser-ignited hydrogen bomb to more sophisticated weapons and civilian applications for power generation. Civilian and military research now overlap, making it possible for several countries to continue weapons activities and permitting proliferation of nuclear weapons. These countries are reluctant to include inertial confinement fusion research in the Non-Proliferation Treaty. 16 references. (DCK)

Smit, W.A.; Boskma, P.

1980-12-01

102

Nuclear Fusion  

NSDL National Science Digital Library

This simple and engaging astronomy activity explains nuclear fusion and how radiation is generated by stars, using marshmallows as a model. Learners will explore what cosmic radiation is and where it comes from, and how the elements in the universe are generated. The PDF contains step-by-step instructions, photos, presentation tips, links to background information, and a printable Periodic Table of the Elements.

Astronomical Society of the Pacific

2008-01-01

103

Fusion process  

Microsoft Academic Search

In energy technology priority discussions, fusion takes varying positions in different countries. In the U.S., the fashion for solar power presently puts nuclear breeders in the shade, but that priority may reverse later; coal is an extended intermediate. In Europe, oil is the intermediate and nuclear is for the long term. Yet all the U.S., Europe, Japan, the U.S.S.R. want

Rose

1978-01-01

104

The Fusion Energy Option  

NASA Astrophysics Data System (ADS)

Presentations from a Fusion Power Associates symposium, The Fusion Energy Option, are summarized. The topics include perspectives on fossil fuel reserves, fusion as a source for hydrogen production, status and plans for the development of inertial fusion, planning for the construction of the International Thermonuclear Experimental Reactor, status and promise of alternate approaches to fusion and the need for R&D now on fusion technologies.

Dean, Stephen O.

2004-06-01

105

Braided Fusion Categories First Conjecture  

E-print Network

Braided Fusion Categories First Conjecture Second Conjecture Braided Weakly Integral Fusion Fusion Categories #12;Braided Fusion Categories First Conjecture Second Conjecture Outline 1 Braided Fusion Categories Preliminaries Dimensions and Braid Representations 2 First Conjecture Finiteness

Rowell, Eric C.

106

Virus membrane fusion  

Microsoft Academic Search

Membrane fusion of enveloped viruses with cellular membranes is mediated by viral glycoproteins (GP). Interaction of GP with cellular receptors alone or coupled to exposure to the acidic environment of endosomes induces extensive conformational changes in the fusion protein which pull two membranes into close enough proximity to trigger bilayer fusion. The refolding process provides the energy for fusion and

Winfried Weissenhorn; Andreas Hinz; Yves Gaudin

2007-01-01

107

Bemerkungen zur "kalten Fusion"  

E-print Network

Steven Jones et al. reported to have observed nuclear fusion at room temperature. They observed this "cold fusion" by electrolyzing heavy water. Later experiments confirmed these observations. These experiments confirmed the generation of strong electric fields within the deuterided metals. These electric fields accelerate the deuterons to keV energies and allow the observed nuclear fusion. Roman Sioda and I suggested a theoretical description of this nuclear fusion. Our "extended micro hot fusion" scenario explains how nuclear fusion can be generated over a long time within deuterided metals. Moreover we predicted the explosion of large pieces of deuterided metals. This article reviews the "cold fusion" work of Steven Jones et al. and discusses the fracto-fusion scenario. I show that the extended micro hot fusion scenario can explain the observed neutron emissions, neutron bursts, and heat bursts.

Rainer W. Kuehne

2006-04-14

108

Anterior lumbar interbody fusion with carbon fiber cage loaded with bioceramics and platelet-rich plasma. An experimental study on pigs  

Microsoft Academic Search

Platelet-rich plasma (PRP) is an autogenous source of growth factor and has been shown to enhance bone healing both in clinical and experimental studies. PRP in combination with porous hydroxyapatite has been shown to increase the bone ingrowth in a bone chamber rat model. The present study investigated whether the combination of beta tricalcium phosphate (?-TCP) and PRP may enhance

Haisheng Li; Xuenong Zou; Qingyun Xue; Niels Egund; Martin Lind; Cody Bünger

2004-01-01

109

Development and Testing of Manufacturing Methods for a Piezoelectric Composite Stacked Generator to Improve the Success Rate of Interbody Spinal Fusion  

E-print Network

method using silver epoxy. Furthermore, this work investigates potential modes of failure and the ability of the specimen to provide an adequate amount of power for electrical stimulation. Three testing stages were conducted to determine potential failure...

Tobaben, Eric

2014-08-31

110

Review of fusion synfuels  

SciTech Connect

Thermonuclear fusion offers an inexhaustible source of energy for the production of hydrogen from water. Depending on design, electric generation efficiencies of approx. 40 to 60% and hydrogen production efficiencies by high-temperature electrolysis of approx. 50 to 65% are projected for fusion reactors using high-temperatures blankets. Fusion/coal symbiotic systems appear economically promising for the first generation of commercial fusion synfuels plants. Coal production requirements and the environmental effects of large-scale coal usage would be greatly reduced by a fusion/coal system. In the long term, there could be a gradual transition to an inexhaustible energy system based solely on fusion.

Fillo, J.A.

1980-01-01

111

Fusion Power Associates, 2011 Annual Meeting 1 General Fusion  

E-print Network

Fusion Power Associates, 2011 Annual Meeting 1 General Fusion #12;Fusion Power Associates, 2011 Annual Meeting 2 General Fusion Making commercially viable fusion power a reality. · Founded in 2002, based in Vancouver, Canada · Plan to demonstrate a fusion system capable of "net gain" within 3 years

112

Fusion Power Associates, 2012 Annual Meeting 1 General Fusion  

E-print Network

Fusion Power Associates, 2012 Annual Meeting 1 General Fusion #12;Fusion Power Associates, 2012 Annual Meeting 2 General Fusion Making affordable fusion power a reality. · Founded in 2002, based to demonstrate the first fusion system capable of "net gain" 3 years after proof · Validated by leading experts

113

Fusion Energy Sciences Program Mission  

E-print Network

Fusion Energy Sciences Program Mission The Fusion Energy Sciences (FES) program leads the national research effort to advance plasma science, fusion science, and fusion technology--the knowledge base needed for an economically and environmentally attractive fusion energy source. The National Energy Policy states that fusion

114

Presented by Information Fusion  

E-print Network

Presented by Information Fusion: Science and Engineering of Combining Information from Multiple's Office of Science #12;2 Managed by UT-Battelle for the U.S. Department of Energy Rao_InfoFusion_SC10 Information Fusion at ORNL · ORNL Instrumental in formulating and fostering this multi-disciplinary area

115

Cluster-impact fusion  

NASA Astrophysics Data System (ADS)

We present a model for the cluster-impact-fusion experiments of Buehler, Friedlander, and Friedman, Calculated fusion rates as a function of bombarding energy for constant cluster size agree well with experiment. The dependence of the fusion rate on cluster size at fixed bombarding energy is explained qualitatively. The role of correlated, coherent collisions in enhanced energy loss by clusters is emphasized.

Echenique, P. M.; Manson, J. R.; Ritchie, R. H.

1990-03-01

116

Cluster-impact fusion  

SciTech Connect

We present a model for the cluster-impact-fusion experiments of Buehler, Friedlander, and Friedman, Calculated fusion rates as a function of bombarding energy for constant cluster size agree well with experiment. The dependence of the fusion rate on cluster size at fixed bombarding energy is explained qualitatively. The role of correlated, coherent collisions in enhanced energy loss by clusters is emphasized.

Echenique, P.M.; Manson, J.R.; Ritchie, R.H. (Departamento de Fisica de Materiales, Facultad de Quimica, Universidad del Pais Vasco, Apartado 1072, San Sebastian 20080, Spain (ES))

1990-03-19

117

Complications due to the use of BMP/INFUSE in spine surgery: The evidence continues to mount.  

PubMed

Increasingly, adverse events (AE) attributed to utilizing BMP/INFUSE (Bone Morphogenetic Protein, Medtronic, Memphis, TN, USA) "off-label" in spine surgery are being reported. In 2008, the Food and Drug Administration (FDA) issued a warning that in anterior cervical spine surgery, the "off-label" use of BMP/INFUSE contributed to marked dysphagia, hematoma, seroma, swelling, and/or the need for intubation/tracheostomy. Subsequent studies have cited the following AE; heterotopic ossification (HO), osteolysis, infection, arachnoiditis, increased neurological deficits, retrograde ejaculation, and cancer. Furthermore, in 2011, Carragee et al. noted that 13 of the original industry-sponsored BMP/INFUSE spinal surgery studies failed to acknowledge multiple AE. Additionally, in 2012, Comer et al. observed that the frequency of retrograde ejaculation reported for BMP/INFUSE used "on-label" to perform Anterior Lumbar Interbody Fusion/Lumbar Tapered Fusion-Cage Device (ALIF/LT-Cage) was also largely "under-reported." To summarize, there is mounting evidence in the spinal literature that utilizing BMP/INFUSE in spinal fusions contributes to major perioperative and postoperative morbidity. PMID:23878769

Epstein, Nancy E

2013-01-01

118

Limited access surgery for 360 degrees in-situ fusion in a dysraphic patient with high-grade spondylolisthesis.  

PubMed

Progressive high-grade spondylolisthesis can lead to spinal imbalance. High-grade spondylolisthesis is often reduced and fused in unbalanced pelvises, whereas in-situ fusion is used more often in balanced patients. The surgical goal is to recreate or maintain sagittal balance but if anatomical reduction is necessary, the risk of nerval damage with nerve root disruption in worst cases is increased. Spinal dysraphism like spina bifida or tethered cord syndrome make it very difficult to achieve reduction and posterior fusion due to altered anatomy putting the focus on anterior column support. Intensive neural structure manipulation should be avoided to reduce neurological complications and re-tethering in these cases. A 26-year-old patient with a history of diastematomyelia, occult spina bifida and tethered cord syndrome presented with new onset of severe low back pain, and bilateral L5/S1 sciatica after a fall. The X-ray demonstrated a grade III spondylolisthesis with spina bifida and the MRI scan revealed bilateral severely narrowed exit foramina L5 due to the listhesis. Because she was well balanced sagittally, the decision for in-situ fusion was made to minimise the risk of neurological disturbance through reduction. Anterior fusion was favoured to minimise manipulation of the dysraphic neural structures. Fusion was achieved via isolated access to the L4/L5 disc space. A L5 transvertebral hollow modular anchorage (HMA) screw was passed into the sacrum from the L4/L5 disc space and interbody fusion of L4/L5 was performed with a cage. The construct was augmented with pedicle screw fixation L4-S1 via a less invasive bilateral muscle split for better anterior biomechanical support. The postoperative course was uneventful and fusion was CT confirmed at the 6-month follow-up. At the last follow-up, she worked full time, was completely pain free and not limited in her free-time activities. The simultaneous presence of high-grade spondylolisthesis and spinal dysraphism make it very difficult to find a decisive treatment plan because both posterior and anterior treatment strategies have advantages and disadvantages in these challenging cases. The described technique combines several surgical options to achieve 360° fusion with limited access, reducing the risk of neurological sequelae. PMID:22008862

König, M A; Boszczyk, B M

2012-03-01

119

Investigation into Fusion Feasibility of a Magnetized Target Fusion Reactor  

E-print Network

Investigation into Fusion Feasibility of a Magnetized Target Fusion Reactor Michael Lindstrom fusion en- ergy known as a magnetized target fusion reactor, in which an intense pressure wave the fusion reactor design we have chosen to model. In section 2, we present a simplified model and set

Wetton, Brian

120

RESEARCH HIGHLIGHTS State of fusion  

E-print Network

RESEARCH HIGHLIGHTS State of fusion In the 1950s,the promise of controlled nuclear fusion, although there is still some way to go to realize the dream,the latest status report on fusion research compiled by the International Fusion Research Council (Nucl. Fusion 45,A1­A28; 2005) provides good reason

Loss, Daniel

121

The European Fusion Programme  

SciTech Connect

The long-term objective of the European fusion programme is the harnessing of the power of fusion to help meet mankind's future energy needs.This paper describes the current research programme, the unique organisational character of the fusion programme, and European and world-wide co-operation. The future evolution of the programme as part of the European Research Area and the developments currently taking place in preparation for the possible construction of ITER, the next major step towards the realisation of fusion power, are discussed.

Antidormi, R.; Bartlett, D.; Bruhns, H. [European Commission (Belgium)

2004-03-15

122

Reconstituted Fusion Pore  

PubMed Central

Fusion pores or porosomes are basket-like structures at the cell plasma membrane, at the base of which, membrane-bound secretory vesicles dock and fuse to release vesicular contents. Earlier studies using atomic force microscopy (AFM) demonstrated the presence of fusion pores at the cell plasma membrane in a number of live secretory cells, revealing their morphology and dynamics at nm resolution and in real time. ImmunoAFM studies demonstrated the release of vesicular contents through the pores. Transmission electron microscopy (TEM) further confirmed the presence of fusion pores, and immunoAFM, and immunochemical studies demonstrated t-SNAREs to localize at the base of the fusion pore. In the present study, the morphology, function, and composition of the immunoisolated fusion pore was investigated. TEM studies reveal in further detail the structure of the fusion pore. Immunoblot analysis of the immunoisolated fusion pore reveals the presence of several isoforms of the proteins, identified earlier in addition to the association of chloride channels. TEM and AFM micrographs of the immunoisolated fusion pore complex were superimposable, revealing its detail structure. Fusion pore reconstituted into liposomes and examined by TEM, revealed a cup-shaped basket-like morphology, and were functional, as demonstrated by their ability to fuse with isolated secretory vesicles. PMID:12944316

Jeremic, Aleksandar; Kelly, Marie; Cho, Sang-Joon; Stromer, Marvin H.; Jena, Bhanu P.

2003-01-01

123

Cost effectiveness of disc prosthesis versus lumbar fusion in patients with chronic low back pain: randomized controlled trial with 2-year follow-up.  

PubMed

This randomized controlled health economic study assesses the cost-effectiveness of the concept of total disc replacement (TDR) (Charité/Prodisc/Maverick) when compared with the concept of instrumented lumbar fusion (FUS) [posterior lumbar fusion (PLF) /posterior lumbar interbody fusion (PLIF)]. Social and healthcare perspectives after 2 years are reported. In all, 152 patients were randomized to either TDR (n = 80) or lumbar FUS (n = 72). Cost to society (total mean cost/patient, Swedish kronor = SEK, standard deviation) for TDR was SEK 599,560 (400,272), and for lumbar FUS SEK 685,919 (422,903) (ns). The difference was not significant: SEK 86,359 (-45,605 to 214,332). TDR was significantly less costly from a healthcare perspective, SEK 22,996 (1,202 to 43,055). Number of days on sick leave among those who returned to work was 185 (146) in the TDR group, and 252 (189) in the FUS group (ns). Using EQ-5D, the total gain in quality adjusted life years (QALYs) over 2 years was 0.41 units for TDR and 0.40 units for FUS (ns). Based on EQ-5D, the incremental cost-effectiveness ratio (ICER) of using TDR instead of FUS was difficult to analyze due to the "non-difference" in treatment outcome, which is why cost/QALY was not meaningful to define. Using cost-effectiveness probabilistic analysis, the net benefit (with CI) was found to be SEK 91,359 (-73,643 to 249,114) (ns). We used the currency of 2006 where 1 EURO = 9.26 SEK and 1 USD = 7.38 SEK. It was not possible to state whether TDR or FUS is more cost-effective after 2 years. Since disc replacement and lumbar fusion are based on different conceptual approaches, it is important to follow these results over time. PMID:21053028

Fritzell, Peter; Berg, Svante; Borgström, Fredrik; Tullberg, Tycho; Tropp, Hans

2011-07-01

124

Controlled Nuclear Fusion.  

ERIC Educational Resources Information Center

This publication is one of a series of information booklets for the general public published by The United States Atomic Energy Commission. Among the topics discussed are: Importance of Fusion Energy; Conditions for Nuclear Fusion; Thermonuclear Reactions in Plasmas; Plasma Confinement by Magnetic Fields; Experiments With Plasmas; High-Temperature…

Glasstone, Samuel

125

Fusion power Bouillabaisse sushi  

E-print Network

://www.economist.com/science/PrinterFriendly.cfm?Story_ID=2404587 #12;gerrymandering recalls the worst of the International Space Station, a collaborative effort be chosen for a new international fusion reactor. This is a pity IF AVANT-GARDE cuisine is any guide, Japanese-French fusion does not work all that well. And the interminable discussions over the International

126

Fusion Plasma Performance Required for Fusion Power The performance achieved on MFE and IFE fusion experiments using DT fuel is compared with the fusion performance  

E-print Network

Fusion Plasma Performance Required for Fusion Power The performance achieved on MFE and IFE fusion experiments using DT fuel is compared with the fusion performance required for a Fusion Power Plant. Const. Cost $B Date

127

Fusion excitation function revisited  

E-print Network

We report on a comprehensive systematics of fusion-evaporation and/or fusion-fission cross sections for a very large variety of systems over an energy range 4-155 A.MeV. Scaled by the reaction cross sections, fusion cross sections do not show a universal behavior valid for all systems although a high degree of correlation is present when data are ordered by the system mass asymmetry.For the rather light and close to mass-symmetric systems the main characteristics of the complete and incomplete fusion excitation functions can be precisely determined. Despite an evident lack of data above 15A.MeV for all heavy systems the available data suggests that geometrical effects could explain the persistence of incomplete fusion at incident energies as high as 155A.MeV.

Ph. Eudes; Z. Basrak; F. Sébille; V. de la Mota; G. Royer; M. Zori?

2012-09-28

128

Electropionics and fusion  

SciTech Connect

This paper reports on the electropionic mass formula which does not differentiate between nuclei and elementary particles, but gives the deuteron a unique bifurcated space-time description. This hints at fusion products produced by anomalous intermediate mass states of 3026, 3194, and 3515 MeV/c{sup 2} that then decay to produce energy. Another unique possibility in electropionics is that no fusion of deuterons occurs, but the deuteron is changed by electron capture into a D-meson that then decays to produce observed cold fusion energies. All these cold fusion electropionic reactions violate baryon conservation but do produce energy yields consistent with reported cold fusion decay products and energy levels.

Kenny, J.P. (Bradley Univ., Dept. of Physics, Peoria, IL (US))

1991-05-01

129

Alperin's Fusion Theorem and Fusion Systems David A. Craven  

E-print Network

Alperin's Fusion Theorem and Fusion Systems David A. Craven September 2010 Abstract This short note provides a new and straightforward proof of the original fusion theorem of Alperin, then considers so-called domestic intersections, which are special types of tame intersections that should play a role in fusion

Craven, David A.

130

Up-Fusion: An Evolving Multimedia Decision Fusion Xiangyu Wang  

E-print Network

Up-Fusion: An Evolving Multimedia Decision Fusion Method Xiangyu Wang National Univ. of Singapore multimedia's nature of hav- ing multiple information sources, fusion methods are criti- cal for its data analysis and understanding. However, most of the traditional fusion methods are static with respect to time

Rui, Yong

131

FUSION NUCLEAR SCIENCE PROGRAM & SUPPORTING FUSION NUCLEAR SCIENCE FACILITY (FNSF)  

E-print Network

FUSION NUCLEAR SCIENCE PROGRAM & SUPPORTING FUSION NUCLEAR SCIENCE FACILITY (FNSF): UPDATE ON DEVELOPING THE MISSION & RESEARCH GOALS Gerald A. Navratil Columbia University Fusion Power Associates 32st in order to apply the knowledge we gained about burning plasma state #12;FUSION NUCLEAR SCIENCE PROGRAM

132

Fusion-Fission Hybrids Driven By Heavy Ion Inertial Fusion  

Microsoft Academic Search

There is a desire to resolve fuel cycle issues for increasing the role of nuclear energy. The recent Laser Inertial Fusion-Fission Energy (LIFE) initiative that builds upon NIF ignition, is likely to rekindle national interest in developing intense, high power ion beam accelerators for fusion energy production and for fusion-fission hybrid concepts that combine an ion beam driven fusion neutron

P. A. Seidl

133

Particle beam fusion  

SciTech Connect

Today, in keeping with Sandia Laboratories` designation by the Department of Energy as the lead laboratory for the pulsed power approach to fusion, its efforts include major research activities and the construction of new facilities at its Albuquerque site. Additionally, in its capacity as lead laboratory, Sandia coordinates DOE-supported pulsed power fusion work at other government operated laboratories, with industrial contractors, and universities. The beginning of Sandia`s involvement in developing fusion power was an outgrowth of its contributions to the nation`s nuclear weapon program. The Laboratories` work in the early 1960`s emphasized the use of pulsed radiation environments to test the resistance of US nuclear weapons to enemy nuclear bursts. A careful study of options for fusion power indicated that Sandia`s expertise in the pulsed power field could provide a powerful match to ignite fusion fuel. Although creating test environments is an achieved goal of Sandia`s overall program, this work and other military tasks protected by appropriate security regulations will continue, making full use of the same pulsed power technology and accelerators as the fusion-for-energy program. Major goals of Sandia`s fusion program including the following: (1) complete a particle accelerator to deliver sufficient beam energy for igniting fusion targets; (2) obtain net energy gain, this goal would provide fusion energy output in excess of energy stored in the accelerator; (3) develop a technology base for the repetitive ignition of pellets in a power reactor. After accomplishing these goals, the technology will be introduced to the nation`s commercial sector.

NONE

1980-12-31

134

Fusion Ignition Research Experiment Highlights  

E-print Network

Fusion Ignition Research Experiment Highlights FY 2004 Fusion Ignition Research Experiment #12;Need is critically needed to advance fusion science," and recommended that: "The United States should participate in the U.S. fusion program. The scientific and technological case for adding a burning plasma experiment

135

Network Fusion Pascal Fradet1  

E-print Network

Network Fusion Pascal Fradet1 and St´ephane Hong Tuan Ha2 1 INRIA Rh^one-Alpes 655, av. de l composition method which strives to reconcile modularity and efficiency. Our technique, network fusion fusion. Fusion allows to replace internal commu- nications by assignments and alleviates most time

Paris-Sud XI, Université de

136

Nuclear fusion - Focus on Tokamak  

Microsoft Academic Search

An overview of nuclear fusion engineering is presented covering: basic fusion technology, magnetic and inertial confinement schemes, fusion fuel, tritium breeding, blankets, tritium containment and disposal, fusion process waste management, power generation costs, environmental impact, and safety. Attention is focused on closed magnetic confinement systems, specifically Tokamak systems. The outlook for pulsed\\/batch or continuous Tokamak operation is assessed. Power supplies

D. Steiner

1977-01-01

137

Feature-level sensor fusion  

Microsoft Academic Search

This paper describes two practical fusion techniques for automatic target cueing that combine features derived from each sensor data ta the object-level. In the hybrid fusion method each of the input sensor data is prescreened before the fusion stage. The cued fusion method assumes that one of the sensors is designated as a primary sensor, and thus ATC is only

Tamar Peli; Mon Young; Robert Knox; Kenneth K. Ellis; Frederick Bennett

1999-01-01

138

Cluster-impact fusion  

SciTech Connect

Deuteron-deuteron fusion, detected via the 3-MeV protons produced, is shown to occur when singly charged clusters of 25 to 1300 D{sub 2}O molecules, accelerated to 200 to 325 keV, impinge on TiD targets. The energy and cluster-size dependence of the fusion rate are discussed. The fusion events are shown to originate from the cluster-ion impacts rather than from D{sup +} or D{sub 2}O{sup +} ions in the beam. The observed rates may be correlated with the compressions and high energy densities created in collision spikes by cluster-ion impacts.

Beuhler, R.J.; Friedlander, G.; Friedman, L. (Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973 (US))

1989-09-18

139

Spherical torus fusion reactor  

DOEpatents

The object of this invention is to provide a compact torus fusion reactor with dramatic simplification of plasma confinement design. Another object of this invention is to provide a compact torus fusion reactor with low magnetic field and small aspect ratio stable plasma confinement. In accordance with the principles of this invention there is provided a compact toroidal-type plasma confinement fusion reactor in which only the indispensable components inboard of a tokamak type of plasma confinement region, mainly a current conducting medium which carries electrical current for producing a toroidal magnet confinement field about the toroidal plasma region, are retained.

Martin Peng, Y.K.M.

1985-10-03

140

Fusion for Space Propulsion  

NASA Technical Reports Server (NTRS)

There is little doubt that humans will attempt to explore and develop the solar system in this century. A large amount of energy will be required for accomplishing this. The need for fusion propulsion is discussed. For a propulsion system, there are three important thermodynamical attributes: (1) The absolute amount of energy available, (2) the propellant exhaust velocity, and (3) the jet power per unit mass of the propulsion system (specific power). For human exploration and development of the solar system, propellant exhaust velocity in excess of 100 km/s and specific power in excess of 10 kW/kg are required. Chemical combustion can produce exhaust velocity up to about 5 km/s. Nuclear fission processes typically result in producing energy in the form of heat that needs to be manipulated at temperatures limited by materials to about 2,800 K. Using the energy to heat a hydrogen propellant increases the exhaust velocity by only a factor of about two. Alternatively the energy can be converted into electricity which is then used to accelerate particles to high exhaust velocity. The necessary power conversion and conditioning equipment, however, increases the mass of the propulsion system for the same jet power by more than two orders of magnitude over chemical system, thus greatly limits the thrust-to-weight ratio attainable. The principal advantage of the fission process is that its development is relatively mature and is available right now. If fusion can be developed, fusion appears to have the best of all worlds in terms of propulsion - it can provide the absolute amount, the propellant exhaust velocity, and the high specific jet power. An intermediate step towards pure fusion propulsion is a bimodal system in which a fission reactor is used to provide some of the energy to drive a fusion propulsion unit. The technical issues related to fusion for space propulsion are discussed. The technical priorities for developing and applying fusion for propulsion are somewhat different from those for terrestrial electrical power generation. Thus fusion schemes that are initially attractive for electrical power generation might not necessarily be attractive also for propulsion and vice versa, though the underlying fusion science and engineering enjoy much overlap. Parallel efforts to develop these qualitatively differently fusion schemes for the two applications could benefit greatly from each other due to the synergy in the underlying physics and engineering. Pulsed approaches to fusion have not been explored to the same degree as steady-state or long-pulse approaches to fusion in the fusion power research program. The concerns early on were several. One was that the pulsed power components might not have the service lifetimes meeting the requirements of a practical power generating plant. Another was that, for many pulsed fusion schemes, it was not clear whether the destruction of hardware per pulse could be minimized or eliminated or recycled to such an extent as to make economical electrical power generation feasible, Significant development of the underlying pulsed power component technologies have occurred in the last two decades because of defense and other energy requirements. The state of development of the pulsed power technologies are sufficiently advanced now to make it compelling to visit or re-visit pulsed fusion approaches for application to propulsion where the cost of energy is not so demanding a factor as in the case of terrestrial power application. For propulsion application, the overall mass of the fusion system is the critical factor. Producing fusion reactions require extreme states of matter. Conceptually, these extreme states of matter are more readily realizable in the pulsed states, at least within appropriate bounds, than in the steady states. Significant saving in system mass may result in such systems. Magnetic fields are effective in confining plasma energy, whereas inertial compression is an effective way of heating and containing the plasma. Intensive research in developing magnetic energy containme

Thio, Y. C. Francis; Schafer, Charles (Technical Monitor)

2001-01-01

141

Spectral Label Fusion  

E-print Network

We present a new segmentation approach that combines the strengths of label fusion and spectral clustering. The result is an atlas-based segmentation method guided by contour and texture cues in the test image. This offers ...

Wachinger, Christian

142

Laser-Driven Fusion.  

ERIC Educational Resources Information Center

Discusses the present status and future prospects of laser-driven fusion. Current research (which is classified under three main headings: laser-matter interaction processes, compression, and laser development) is also presented. (HM)

Gibson, A. F.

1980-01-01

143

Fusion: The Hydrogen Bomb  

NSDL National Science Digital Library

Just after World War II, nuclear scientists turned their attention from fission to fusion. This video segment adapted from AMERICAN EXPERIENCE looks at the beginnings of thermonuclear power generation.

2004-02-20

144

Magnetized Target Fusion  

NASA Technical Reports Server (NTRS)

Magnetized target fusion (MTF) is under consideration as a means of building a low mass, high specific impulse, and high thrust propulsion system for interplanetary travel. This unique combination is the result of the generation of a high temperature plasma by the nuclear fusion process. This plasma can then be deflected by magnetic fields to provide thrust. Fusion is initiated by a small traction of the energy generated in the magnetic coils due to the plasma's compression of the magnetic field. The power gain from a fusion reaction is such that inefficiencies due to thermal neutrons and coil losses can be overcome. Since the fusion reaction products are directly used for propulsion and the power to initiate the reaction is directly obtained from the thrust generation, no massive power supply for energy conversion is required. The result should be a low engine mass, high specific impulse and high thrust system. The key is to successfully initiate fusion as a proof-of-principle for this application. Currently MSFC is implementing MTF proof-of-principle experiments. This involves many technical details and ancillary investigations. Of these, selected pertinent issues include the properties, orientation and timing of the plasma guns and the convergence and interface development of the "pusher" plasma. Computer simulations of the target plasma's behavior under compression and the convergence and mixing of the gun plasma are under investigation. This work is to focus on the gun characterization and development as it relates to plasma initiation and repeatability.

Griffin, Steven T.

2002-01-01

145

ITER Fusion Energy  

SciTech Connect

ITER (in Latin “the way”) is designed to demonstrate the scientific and technological feasibility of fusion energy. Fusion is the process by which two light atomic nuclei combine to form a heavier over one and thus release energy. In the fusion process two isotopes of hydrogen – deuterium and tritium – fuse together to form a helium atom and a neutron. Thus fusion could provide large scale energy production without greenhouse effects; essentially limitless fuel would be available all over the world. The principal goals of ITER are to generate 500 megawatts of fusion power for periods of 300 to 500 seconds with a fusion power multiplication factor, Q, of at least 10. Q ? 10 (input power 50 MW / output power 500 MW). The ITER Organization was officially established in Cadarache, France, on 24 October 2007. The seven members engaged in the project – China, the European Union, India, Japan, Korea, Russia and the United States – represent more than half the world’s population. The costs for ITER are shared by the seven members. The cost for the construction will be approximately 5.5 billion Euros, a similar amount is foreseen for the twenty-year phase of operation and the subsequent decommissioning.

Dr. Norbert Holtkamp

2009-12-01

146

ITER Fusion Energy  

ScienceCinema

ITER (in Latin ?the way?) is designed to demonstrate the scientific and technological feasibility of fusion energy. Fusion is the process by which two light atomic nuclei combine to form a heavier over one and thus release energy. In the fusion process two isotopes of hydrogen ? deuterium and tritium ? fuse together to form a helium atom and a neutron. Thus fusion could provide large scale energy production without greenhouse effects; essentially limitless fuel would be available all over the world. The principal goals of ITER are to generate 500 megawatts of fusion power for periods of 300 to 500 seconds with a fusion power multiplication factor, Q, of at least 10. Q ? 10 (input power 50 MW / output power 500 MW). The ITER Organization was officially established in Cadarache, France, on 24 October 2007. The seven members engaged in the project ? China, the European Union, India, Japan, Korea, Russia and the United States ? represent more than half the world?s population. The costs for ITER are shared by the seven members. The cost for the construction will be approximately 5.5 billion Euros, a similar amount is foreseen for the twenty-year phase of operation and the subsequent decommissioning.

Dr. Norbert Holtkamp

2010-01-08

147

Identification of cancer fusion drivers using network fusion centrality  

PubMed Central

Summary: Gene fusions are being discovered at an increasing rate using massively parallel sequencing technologies. Prioritization of cancer fusion drivers for validation cannot be performed using traditional single-gene based methods because fusions involve portions of two partner genes. To address this problem, we propose a novel network analysis method called fusion centrality that is specifically tailored for prioritizing gene fusions. We first propose a domain-based fusion model built on the theory of exon/domain shuffling. The model leads to a hypothesis that a fusion is more likely to be an oncogenic driver if its partner genes act like hubs in a network because the fusion mutation can deregulate normal functions of many other genes and their pathways. The hypothesis is supported by the observation that for most known cancer fusion genes, at least one of the fusion partners appears to be a hub in a network, and even for many fusions both partners appear to be hubs. Based on this model, we construct fusion centrality, a multi-gene-based network metric, and use it to score fusion drivers. We show that the fusion centrality outperforms other single gene-based methods. Specifically, the method successfully predicts most of 38 newly discovered fusions that had validated oncogenic importance. To our best knowledge, this is the first network-based approach for identifying fusion drivers. Availability: Matlab code implementing the fusion centrality method is available upon request from the corresponding authors. Contact: perwu777@gmail.com Supplementary information: Supplementary data are available at Bioinformatics online. PMID:23505294

Wu, Chia-Chin; Kannan, Kalpana; Lin, Steven; Yen, Laising; Milosavljevic, Aleksandar

2013-01-01

148

Biomechanical evaluation of an endplate-conformed polycaprolactone-hydroxyapatite intervertebral fusion graft and its comparison with a typical nonconformed cortical graft.  

PubMed

In the thoracolumbar region, between 7% and 30% of spinal fusion failures are at risk for pseudarthrosis. From a biomechanical perspective, the nonconformity of the intervertebral graft to the endplate surface could contribute to pseudarthrosis, given suboptimal stress distributions. The objective of this study was to quantify the effect of endplate-graft conformation on endplate stress distribution, maximum Von Mises stress development, and stability. The study design used an experimentally validated finite element (FE) model of the L4-L5 functional spinal unit to simulate two types of interbody grafts (cortical bone and polycaprolactone (PCL)-hydroxyapatite (HA) graft), with and without endplate-conformed surfaces. Two case studies were completed. In Case Study I, the endplate-conformed grafts and nonconformed grafts were compared under without posterior instrumentation condition, while in Case Study II, the endplate-conformed and nonconformed grafts were compared with posterior instrumentation. In both case studies, the results suggested that the increased endplate-graft conformity reduced the maximum stress on the endplate, created uniform stress distribution on endplate surfaces, and reduced the range of motion of L4-L5 segments by increasing the contact surface area between the graft and the endplate. The stress distributions in the endplate suggest that the load sharing is greater with the endplate-conformed PCL-HA graft, which might reduce the graft subsidence possibility. PMID:23699717

Agarwal, Aakash; Palepu, Vivek; Agarwal, Anand K; Goel, Vijay K; Yildirim, Eda D

2013-06-01

149

Myoblast fusion in Drosophila  

SciTech Connect

The body wall musculature of a Drosophila larva is composed of an intricate pattern of 30 segmentally repeated muscle fibers in each abdominal hemisegment. Each muscle fiber has unique spatial and behavioral characteristics that include its location, orientation, epidermal attachment, size and pattern of innervation. Many, if not all, of these properties are dictated by founder cells, which determine the muscle pattern and seed the fusion process. Myofibers are then derived from fusion between a specific founder cell and several fusion competent myoblasts (FCMs) fusing with as few as 3-5 FCMs in the small muscles on the most ventral side of the embryo and as many as 30 FCMs in the larger muscles on the dorsal side of the embryo. The focus of the present review is the formation of the larval muscles in the developing embryo, summarizing the major issues and players in this process. We have attempted to emphasize experimentally-validated details of the mechanism of myoblast fusion and distinguish these from the theoretically possible details that have not yet been confirmed experimentally. We also direct the interested reader to other recent reviews that discuss myoblast fusion in Drosophila, each with their own perspective on the process . With apologies, we use gene nomenclature as specified by Flybase (http://flybase.org) but provide Table 1 with alternative names and references.

Haralalka, Shruti [Stowers Institute for Medical Research, Kansas City, MO 64110 (United States)] [Stowers Institute for Medical Research, Kansas City, MO 64110 (United States); Abmayr, Susan M., E-mail: sma@stowers.org [Stowers Institute for Medical Research, Kansas City, MO 64110 (United States); Department of Anatomy and Cell Biology, University of Kansas Medical Center, Kansas City, MO 66160 (United States)

2010-11-01

150

Fusion, magnetic confinement  

SciTech Connect

An overview is presented of the principles of magnetic confinement of plasmas for the purpose of achieving controlled fusion conditions. Sec. 1 discusses the different nuclear fusion reactions which can be exploited in prospective fusion reactors and explains why special technologies need to be developed for the supply of tritium or {sup 3}He, the probable fuels. In Sec. 2 the Lawson condition, a criterion that is a measure of the quality of confinement relative to achieving fusion conditions, is explained. In Sec. 3 fluid equations are used to describe plasma confinement. Specific confinement configurations are considered. In Sec. 4 the orbits of particle sin magneti and electric fields are discussed. In Sec. 5 stability considerations are discussed. It is noted that confinement systems usually need to satisfy stability constraints imposed by ideal magnetohydrodynamic (MHD) theory. The paper culminates with a summary of experimental progress in magnetic confinement. Present experiments in tokamaks have reached the point that the conditions necessary to achieve fusion are being satisfied.

Berk, H.L.

1992-08-06

151

Realization of Fusion Energy: An alternative fusion roadmap  

E-print Network

Realization of Fusion Energy: An alternative fusion roadmap Farrokh Najmabadi Professor of Electrical & Computer Engineering Director, Center for Energy Research UC San Diego International Fusion Road of emerging nations, energy use is expected to grow ~ 4 fold in this century (average 1.6% annual growth rate

152

Simulation of Fusion Plasmas  

ScienceCinema

The upcoming ITER experiment (www.iter.org) represents the next major milestone in realizing the promise of using nuclear fusion as a commercial energy source, by moving into the ?burning plasma? regime where the dominant heat source is the internal fusion reactions. As part of its support for the ITER mission, the US fusion community is actively developing validated predictive models of the behavior of magnetically confined plasmas. In this talk, I will describe how the plasma community is using the latest high performance computing facilities to develop and refine our models of the nonlinear, multiscale plasma dynamics, and how recent advances in experimental diagnostics are allowing us to directly test and validate these models at an unprecedented level.

Chris Holland

2010-01-08

153

Cryogenics for Fusion  

NASA Astrophysics Data System (ADS)

Fusion of Hydrogen to produce energy is one of the technologies under study to meet the mankind raising need in energy and as a substitute to fossil fuels for the future. This technology is under investigation for more than 30 years already, with, for example, the former construction of the experimental reactors Tore Supra, DIII-D and JET. With the construction of ITER to start, the next step to "fusion for energy" will be done. In these projects, an extensive use of cryogenic systems is requested. Air Liquide has been involved as cryogenic partner in most of former and presently constructed fusion reactors. In the present paper, a review of the cryogenic systems we delivered to Tore Supra, JET, IPR and KSTAR will be presented.

Dauguet, P.; Gistau-Baguer, G. M.; Bonneton, M.; Boissin, J. C.; Fauve, E.; Bernhardt, J. M.; Beauvisage, J.; Andrieu, F.

2008-03-01

154

Ceramics for fusion devices  

SciTech Connect

Ceramics are required for a number of applications in fusion devices, among the most critical of which are magnetic coil insulators, windows for RF heating systems, and structural uses. Radiation effects dominate consideration of candidate materials, although good pre-irradiation properties are a requisite. Materials and components can be optimized by careful control of chemical and microstructural content, and application of brittle material design and testing techniques. Future directions for research and development should include further extension of the data base in the areas of electrical, structural, and thermal properties; establishment of a fission neutron/fusion neutron correlation including transmutation gas effects; and development of new materials tailored to meet the specific needs of fusion reactors.

Clinard, F.W. Jr.

1984-01-01

155

Fusion for Space Propulsion  

NASA Technical Reports Server (NTRS)

The need for fusion propulsion for interplanetary flights is discussed. For a propulsion system, there are three important system attributes: (1) The absolute amount of energy available, (2) the propellant exhaust velocity, and (3) the jet power per unit mass of the propulsion system (specific power). For efficient and affordable human exploration of the solar system, propellant exhaust velocity in excess of 100 km/s and specific power in excess of 10 kW/kg are required. Chemical combustion obviously cannot meet the requirement in propellant exhaust velocity. Nuclear fission processes typically result in producing energy in the form of heat that needs to be manipulated at temperatures limited by materials to about 2,800 K. Using the fission energy to heat a low atomic weight propellant produces propellant velocity of the order of 10 kinds. Alternatively the fission energy can be converted into electricity that is used to accelerate particles to high exhaust velocity. However, the necessary power conversion and conditioning equipment greatly increases the mass of the propulsion system. Fundamental considerations in waste heat rejection and power conditioning in a fission electric propulsion system place a limit on its jet specific power to the order of about 0.2 kW/kg. If fusion can be developed for propulsion, it appears to have the best of all worlds - it can provide the largest absolute amount of energy, the propellant exhaust velocity (> 100 km/s), and the high specific jet power (> 10 kW/kg). An intermediate step towards fusion propulsion might be a bimodal system in which a fission reactor is used to provide some of the energy to drive a fusion propulsion unit. There are similarities as well as differences between applying fusion to propulsion and to terrestrial electrical power generation. The similarities are the underlying plasma and fusion physics, the enabling component technologies, the computational and the diagnostics capabilities. These physics and engineering capabilities have been demonstrated for a fusion reactor gain (Q) of the order of unity (TFTR: 0.25, JET: 0.65, JT-60: Q(sub eq) approx. 1.25). These technological advances made it compelling for considering fusion for propulsion.

Thio, Y. C. Francis; Schmidt, George R.; Santarius, John F.; Turchi, Peter J.; Siemon, Richard E.; Rodgers, Stephen L. (Technical Monitor)

2002-01-01

156

Fusion welding process  

DOEpatents

A process for the fusion welding of nickel alloy steel members wherein a ferrite containing pellet is inserted into a cavity in one member and melted by a welding torch. The resulting weld nugget, a fusion of the nickel containing alloy from the members to be welded and the pellet, has a composition which is sufficiently low in nickel content such that ferrite phases occur within the weld nugget, resulting in improved weld properties. The steel alloys encompassed also include alloys containing carbon and manganese, considered nickel equivalents.

Thomas, Kenneth C. (Export, PA); Jones, Eric D. (Salem, PA); McBride, Marvin A. (Hempfield Township, Westmoreland County, PA)

1983-01-01

157

The Fusion Machine (extended abstract)  

E-print Network

The Fusion Machine (extended abstract) Philippa Gardner Cosimo Laneve Lucian Wischik March 27, 2002. In particular, we describe a dis- tributed abstract machine called the fusion machine. In it, only channels exist at runtime. It uses a form of concurrent constraints called fusions--equations on channel names

Gardner, Philippa

158

Human-Centered Fusion Framework  

SciTech Connect

In recent years the benefits of fusing signatures extracted from large amounts of distributed and/or heterogeneous data sources have been largely documented in various problems ranging from biological protein function prediction to cyberspace monitoring. In spite of significant progress in information fusion research, there is still no formal theoretical framework for defining various types of information fusion systems, defining and analyzing relations among such types, and designing information fusion systems using a formal method approach. Consequently, fusion systems are often poorly understood, are less than optimal, and/or do not suit user needs. To start addressing these issues, we outline a formal humancentered fusion framework for reasoning about fusion strategies. Our approach relies on a new taxonomy for fusion strategies, an alternative definition of information fusion in terms of parameterized paths in signature related spaces, an algorithmic formalization of fusion strategies and a library of numeric and dynamic visual tools measuring the impact as well as the impact behavior of fusion strategies. Using a real case of intelligence analysis we demonstrate that the proposed framework enables end users to rapidly 1) develop and implement alternative fusion strategies, 2) understand the impact of each strategy, 3) compare the various strategies, and 4) perform the above steps without having to know the mathematical foundations of the framework. We also demonstrate that the human impact on a fusion system is critical in the sense that small changes in strategies do not necessarily correspond to small changes in results.

Posse, Christian; White, Amanda M.; Beagley, Nathaniel

2007-05-16

159

Control of Fusion and Solubility in Fusion Systems David A. Craven  

E-print Network

Control of Fusion and Solubility in Fusion Systems David A. Craven March 2009 Abstract In this article, we consider control of fusion, quotients, and p-soluble fusion systems. For control of fusion, we for fusion systems. We move on to p-soluble fusion systems, and prove that they are constrained, allowing us

Craven, David A.

160

Separating Fusion from Rivalry  

PubMed Central

Visual fusion is the process in which differing but compatible binocular information is transformed into a unified percept. Even though this is at the basis of binocular vision, the underlying neural processes are, as yet, poorly understood. In our study we therefore aimed to investigate neural correlates of visual fusion. To this end, we presented binocularly compatible, fusible (BF), and incompatible, rivaling (BR) stimuli, as well as an intermediate stimulus type containing both binocularly fusible and monocular, incompatible elements (BFR). Comparing BFR stimuli with BF and BR stimuli, respectively, we were able to disentangle brain responses associated with either visual fusion or rivalry. By means of functional magnetic resonance imaging, we measured brain responses to these stimulus classes in the visual cortex, and investigated them in detail at various retinal eccentricities. Compared with BF stimuli, the response to BFR stimuli was elevated in visual cortical areas V1 and V2, but not in V3 and V4 – implying that the response to monocular stimulus features decreased from V1 to V4. Compared to BR stimuli, the response to BFR stimuli decreased with increasing eccentricity, specifically within V3 and V4. Taken together, it seems that although the processing of exclusively monocular information decreases from V1 to V4, the processing of binocularly fused information increases from earlier to later visual areas. Our findings suggest the presence of an inhibitory neural mechanism which, depending on the presence of fusion, acts differently on the processing of monocular information. PMID:25054904

Dechent, Peter; Forster, Clemens; von Steinbüchel, Nicole; Wüstenberg, Torsten; Strasburger, Hans

2014-01-01

161

Mars manned fusion spaceship  

NASA Technical Reports Server (NTRS)

Fusion Propulsion has an enormous potential for space exploration in the near future. In the twenty-first century, a usable and efficient fusion rocket will be developed and in use. Because of the great distance between other planets and Earth, efficient use of time, fuel, and payload is essential. A nuclear spaceship would provide greater fuel efficiency, less travel time, and a larger payload. Extended missions would give more time for research, experiments, and data acquisition. With the extended mission time, a need for an artificial environment exists. The topics of magnetic fusion propulsion, living modules, artificial gravity, mass distribution, space connection, and orbital transfer to Mars are discussed. The propulsion system is a magnetic fusion reactor based on a tandem mirror design. This allows a faster, shorter trip time and a large thrust to weight ratio. The fuel proposed is a mixture of deuterium and helium-3. Helium-3 can be obtained from lunar mining. There will be minimal external radiation from the reactor resulting in a safe, efficient propulsion system.

Hedrick, James; Buchholtz, Brent; Ward, Paul; Freuh, Jim; Jensen, Eric

1991-01-01

162

Fusion unit preventive maintenance  

SciTech Connect

The lack of preventive maintenance on any mechanical apparatus can lead to the death of that machine. Experience with fusion equipment, as well as other special purpose equipment manufactured has shown that improperly maintained equipment will require overhaul maintenance from 6 to 10 times earlier than a properly maintained one. This figure can probably be used for most pieces of equipment. The principle of heat fusion is to heat two opposing surfaces of a polyolefin material to a designated temperature, then fuse them together by application of a designated force. This causes flow of the melted materials that results in mixing of the molecular chains and thus fusion. Polyethylene consists of crystalline and amorphous materials, but for all practical purposes, at normal ambient temperatures, it is basically a crystalline structure. When the polyethylene is heated beyond melting temperature, the crystallinity disappears completely and the molecular structure becomes completely amorphous (has no definite shape). When fusion force is applied, the amorphous molecules from each pipe end or fitting mix. As the joint cools below the crystalline melting point, the molecular chain becomes crystalline again. When proper mixing occurs, crystals are formed from one pipe through the joining plane to the other pipe. The original interfaces are gone and the two pipes or fittings have become one homogenous material. The joint area becomes stronger than the pipe or fitting themselves.

Striplin, T.H.

1986-07-01

163

Fusion of conformal interfaces  

Microsoft Academic Search

We study the fusion of conformal interfaces in the c = 1 conformal field theory. We uncover an elegant structure reminiscent of that of black holes in supersymmetric theories. The role of the BPS black holes is played by topological interfaces, which (a) minimize the entropy function, (b) fix through an attractor mechanism one or both of the bulk radii,

C. Bachas; I. Brunner

2008-01-01

164

About sponsorship Fusion power  

E-print Network

with the International Space Station. It is scheduled to run for 30 years, which is handy since, for the past half the International Space Station, had its origins in the superpower politics of the 1980s that brought the cold A step towards commercial fusion power. Perhaps Get article background THIS week, an international

165

Accelerators for heavy ion fusion  

SciTech Connect

Large fusion devices will almost certainly produce net energy. However, a successful commercial fusion energy system must also satisfy important engineering and economic constraints. Inertial confinement fusion power plants driven by multi-stage, heavy-ion accelerators appear capable of meeting these constraints. The reasons behind this promising outlook for heavy-ion fusion are given in this report. This report is based on the transcript of a talk presented at the Symposium on Lasers and Particle Beams for Fusion and Strategic Defense at the University of Rochester on April 17-19, 1985.

Bangerter, R.O.

1985-10-01

166

Enhanced image capture through fusion  

NASA Technical Reports Server (NTRS)

Image fusion may be used to combine images from different sensors, such as IR and visible cameras, to obtain a single composite with extended information content. Fusion may also be used to combine multiple images from a given sensor to form a composite image in which information of interest is enhanced. We present a general method for performing image fusion and show that this method is effective for diverse fusion applications. We suggest that fusion may provide a powerful tool for enhanced image capture with broad utility in image processing and computer vision.

Burt, Peter J.; Hanna, Keith; Kolczynski, Raymond J.

1993-01-01

167

Stau-catalyzed Nuclear Fusion  

E-print Network

We point out that the stau may play a role of a catalyst for nuclear fusions if the stau is a long-lived particle as in the scenario of gravitino dark matter. In this letter, we consider d d fusion under the influence of stau where the fusion is enhanced because of a short distance between the two deuterons. We find that one chain of the d d fusion may release an energy of O(10) GeV per stau. We discuss problems of making the stau-catalyzed nuclear fusion of practical use with the present technology of producing stau.

K. Hamaguchi; T. Hatsuda; T. T. Yanagida

2006-07-24

168

Research on fusion neutron sources  

SciTech Connect

The use of fusion devices as powerful neutron sources has been discussed for decades. Whereas the successful route to a commercial fusion power reactor demands steady state stable operation combined with the high efficiency required to make electricity production economic, the alternative approach to advancing the use of fusion is free of many of complications connected with the requirements for economic power generation and uses the already achieved knowledge of Fusion physics and developed Fusion technologies. 'Fusion for Neutrons' (F4N), has now been re-visited, inspired by recent progress achieved on comparably compact fusion devices, based on the Spherical Tokamak (ST) concept. Freed from the requirement to produce much more electricity than used to drive it, a fusion neutron source could be efficiently used for many commercial applications, and also to support the goal of producing energy by nuclear power. The possibility to use a small or medium size ST as a powerful or intense steady-state fusion neutron source (FNS) is discussed in this paper in comparison with the use of traditional high aspect ratio tokamaks. An overview of various conceptual designs of compact fusion neutron sources based on the ST concept is given and they are compared with a recently proposed Super Compact Fusion Neutron Source (SCFNS), with major radius as low as 0.5 metres but still able to produce several MW of neutrons in a steady-state regime.

Gryaznevich, M. P. [Tokamak Solutions UK, Culham Science Centre, Abingdon, OXON, OX133DB (United Kingdom)

2012-06-19

169

The path to fusion power.  

PubMed

Fusion is potentially an environmentally responsible and intrinsically safe source of essentially limitless power. It should be possible to build viable fusion power stations, and it looks as if the cost of fusion power will be reasonable. But time is needed to further develop the technology and to test in power station conditions the materials that would be used in their construction. Assuming no major adverse surprises, an orderly fusion development programme could lead to a prototype fusion power station putting electricity into the grid within 30 years, with commercial fusion power following some 10 or more years later. In the second half of the century, fusion could therefore be an important part of the portfolio of measures that are needed to cope with rising demand for energy in an environmentally responsible manner. In this paper, we describe the basics of fusion, its potential attractions, the status of fusion R&D, the remaining challenges and how they will be tackled at the International Tokamak Experimental Reactor and the proposed International Fusion Materials Irradiation Facility, and the timetable for the subsequent commercialization of fusion power. PMID:17272246

Llewellyn Smith, Chris; Ward, David

2007-04-15

170

Research on fusion neutron sources  

NASA Astrophysics Data System (ADS)

The use of fusion devices as powerful neutron sources has been discussed for decades. Whereas the successful route to a commercial fusion power reactor demands steady state stable operation combined with the high efficiency required to make electricity production economic, the alternative approach to advancing the use of fusion is free of many of complications connected with the requirements for economic power generation and uses the already achieved knowledge of Fusion physics and developed Fusion technologies. "Fusion for Neutrons" (F4N), has now been re-visited, inspired by recent progress achieved on comparably compact fusion devices, based on the Spherical Tokamak (ST) concept. Freed from the requirement to produce much more electricity than used to drive it, a fusion neutron source could be efficiently used for many commercial applications, and also to support the goal of producing energy by nuclear power. The possibility to use a small or medium size ST as a powerful or intense steady-state fusion neutron source (FNS) is discussed in this paper in comparison with the use of traditional high aspect ratio tokamaks. An overview of various conceptual designs of compact fusion neutron sources based on the ST concept is given and they are compared with a recently proposed Super Compact Fusion Neutron Source (SCFNS), with major radius as low as 0.5 metres but still able to produce several MW of neutrons in a steady-state regime.

Gryaznevich, M. P.

2012-06-01

171

The Need for Fusion Propulsion  

NASA Technical Reports Server (NTRS)

Fusion propulsion is inevitable if the human race remains dedicated to exploration of the solar system. There are fundamental reasons why fusion surpasses more traditional approaches to routine crewed missions to Mars, crewed missions to the outer planets, and deep space high speed robotic missions, assuming that reduced trip times, increased payloads, and higher available power are desired. A recent series of informal discussions were held among members from government, academia, and industry concerning fusion propulsion. We compiled a sufficient set of arguments for utilizing fusion in space. If the U.S. is to lead the effort and produce a working system in a reasonable amount of time, NASA must take the initiative, relying on, but not waiting for, DOE guidance. In this talk those arguments for fusion propulsion are presented, along with fusion enabled mission examples, fusion technology trade space, and a proposed outline for future efforts.

Cassibry, Jason

2005-01-01

172

Fusion pumped laser  

DOEpatents

The apparatus of this invention may comprise a system for generating laser radiation from a high-energy neutron source. The neutron source is a tokamak fusion reactor generating a long pulse of high-energy neutrons and having a temperature and magnetic field effective to generate a neutron flux of at least 10/sup 15/ neutrons/cm/sup 2//center dot/s. Conversion means are provided adjacent the fusion reactor at a location operable for converting the high-energy neutrons to an energy source with an intensity and energy effective to excite a preselected lasing medium. A lasing medium is spaced about and responsive to the energy source to generate a population inversion effective to support laser oscillations for generating output radiation. 2 figs., 2 tabs.

Pappas, D.S.

1987-07-31

173

Teachers Debate Cold Fusion  

NASA Astrophysics Data System (ADS)

What follows is a collection of messages about cold fusion from teachers. The messages were posted on the internet discussion list, Phys-L, or were sent to me in private. They illustrate a wide range of opinion. Phys-L is a list dedicated to learning and teaching physics with 700 subscribers from over 35 countries, the majority of whom are physics educators. <>.

Kowalski, Ludwik

2005-12-01

174

Tokamak fusion power reactors  

Microsoft Academic Search

The major parameters and corresponding economic characteristics of a representative class of commercial Tokamak fusion power reactors are examined as a function of four major design parameters: plasma beta-t, toroidal magnetic field strength, first-wall lifetime, and power output. It is shown that for beta-t greater than or equal to 0.06, the minimum cost of energy is obtained for toroidal field

W. M. Stacey Jr.; M. A. Abdou

1978-01-01

175

Fusion development and technology  

SciTech Connect

This report discusses the following: superconducting magnet technology; high field superconductors; advanced magnetic system and divertor development; poloidal field coils; gyrotron development; commercial reactor studies--aries; ITER physics: alpha physics and alcator R D for ITER; lower hybrid current drive and heating in the ITER device; ITER superconducting PF scenario and magnet analysis; ITER systems studies; and safety, environmental and economic factors in fusion development.

Montgomery, D.B.

1992-01-01

176

Modular Aneutronic Fusion Engine  

SciTech Connect

NASA's JUNO mission will arrive at Jupiter in July 2016, after nearly five years in space. Since operational costs tend to rise with mission time, minimizing such times becomes a top priority. We present the conceptual design for a 10MW aneutronic fusion engine with high exhaust velocities that would reduce transit time for a Jupiter mission to eighteen months and enable more challenging exploration missions in the solar system and beyond. __________________________________________________

Gary Pajer, Yosef Razin, Michael Paluszek, A.H. Glasser and Samuel Cohen

2012-05-11

177

Inertial Confinement fusion targets  

NASA Technical Reports Server (NTRS)

Inertial confinement fusion (ICF) targets are made as simple flat discs, as hollow shells or as complicated multilayer structures. Many techniques were devised for producing the targets. Glass and metal shells are made by using drop and bubble techniques. Solid hydrogen shells are also produced by adapting old methods to the solution of modern problems. Some of these techniques, problems, and solutions are discussed. In addition, the applications of many of the techniques to fabrication of ICF targets is presented.

Hendricks, C. D.

1982-01-01

178

High Level Information Fusion (HLIF) with nested fusion loops  

NASA Astrophysics Data System (ADS)

Situation modeling and threat prediction require higher levels of data fusion in order to provide actionable information. Beyond the sensor data and sources the analyst has access to, the use of out-sourced and re-sourced data is becoming common. Through the years, some common frameworks have emerged for dealing with information fusion—perhaps the most ubiquitous being the JDL Data Fusion Group and their initial 4-level data fusion model. Since these initial developments, numerous models of information fusion have emerged, hoping to better capture the human-centric process of data analyses within a machine-centric framework. 21st Century Systems, Inc. has developed Fusion with Uncertainty Reasoning using Nested Assessment Characterizer Elements (FURNACE) to address challenges of high level information fusion and handle bias, ambiguity, and uncertainty (BAU) for Situation Modeling, Threat Modeling, and Threat Prediction. It combines JDL fusion levels with nested fusion loops and state-of-the-art data reasoning. Initial research has shown that FURNACE is able to reduce BAU and improve the fusion process by allowing high level information fusion (HLIF) to affect lower levels without the double counting of information or other biasing issues. The initial FURNACE project was focused on the underlying algorithms to produce a fusion system able to handle BAU and repurposed data in a cohesive manner. FURNACE supports analyst's efforts to develop situation models, threat models, and threat predictions to increase situational awareness of the battlespace. FURNACE will not only revolutionize the military intelligence realm, but also benefit the larger homeland defense, law enforcement, and business intelligence markets.

Woodley, Robert; Gosnell, Michael; Fischer, Amber

2013-05-01

179

COLLABORATIVE: FUSION SIMULATION PROGRAM  

SciTech Connect

New York University, Courant Institute of Mathematical Sciences, participated in the ���¢��������Fusion Simulation Program (FSP) Planning Activities���¢������� [http://www.pppl.gov/fsp], with C.S. Chang as the institutional PI. FSP���¢��������s mission was to enable scientific discovery of important new plasma phenomena with associated understanding that emerges only upon integration. This requires developing a predictive integrated simulation capability for magnetically-confined fusion plasmas that are properly validated against experiments in regimes relevant for producing practical fusion energy. Specific institutional goal of the New York University was to participate in the planning of the edge integrated simulation, with emphasis on the usage of large scale HPCs, in connection with the SciDAC CPES project which the PI was leading. New York University successfully completed its mission by participating in the various planning activities, including the edge physics integration, the edge science drivers, and the mathematical verification. The activity resulted in the combined report that can be found in http://www.pppl.gov/fsp/Overview.html. Participation and presentations as part of this project are listed in a separation file.

Chang, Choong Seock

2012-06-05

180

Fusion Policy Advisory Committee FINAL REPORT  

E-print Network

Fusion Policy Advisory Committee (FPAC) FINAL REPORT September 1990 Report of the Technical Panel on Magnetic Fusion of the Energy Research Advisory Board Washington, D .C. 20585 #12;#12;Fusion Policy of your Fusion Policy Advisory Committee. It presents a fusion policy that the Committee believes

181

Fusion power production in TFTR  

SciTech Connect

Up to 9.3 MW of fusion power has been produced from deuterium-tritium (DT) fusion reactions in the Tokamak Fusion Test Reactor (TFTR). The total fusion yield from a single plasma pulse has reached 6.5 MJ. The experiments in TFTR with deuterium-tritium plasmas fueled and heated by neutral beam injection span wide ranges in plasma and operating conditions. Through the use of lithium pellet conditioning to control the edge recycling, the plasma confinement in TFTR has been improved to the point where the stability of the plasma to pressure driven modes is limiting the fusion power for plasma currents up to 2.5 MA. The central energy and fusion power densities in these plasmas are comparable to those expected in a thermalized DT reactor, such as ITER.

Bell, M.G.; Budny, R.V. [Princeton Univ., NJ (United States). Plasma Physics Lab.; Barnes, C.W. [Los Alamos National Lab., NM (United States)] [and others

1994-11-01

182

The path to fusion power†  

PubMed Central

The promise, status and challenges of developing fusion power are outlined. The key physics and engineering principles are described and recent progress quantified. As the successful demonstration of 16?MW of fusion in 1997 in the Joint European Torus showed, fusion works. The central issue is therefore to make it work reliably and economically on the scale of a power station. We argue that to meet this challenge in 30 years we must follow the aggressive programme known as the ‘Fast Track to Fusion’. This programme is described in some detail. PMID:20123748

Smith, Chris Llewellyn; Cowley, Steve

2010-01-01

183

Fusion rings for quantum groups  

E-print Network

We study the fusion rings of tilting modules for a quantum group at a root of unity modulo the tensor ideal of negligible tilting modules. We identify them in type A with the combinatorial rings from [KS] and give a similar description of the sp(2n)-fusion ring in terms of noncommutative symmetric functions. Moreover we give a presentation of all fusion rings in classical types as quotients of polynomial rings extending known results in special cases. Finally we also compute the fusion rings for type G2.

Henning Haahr Andersen; Catharina Stroppel

2014-04-02

184

Mitochondrial Fusion and Fission in Mammals  

E-print Network

Mitochondrial Fusion and Fission in Mammals David C. Chan Division of Biology, California Institute dynamics, organelle morphology, membrane fusion, membrane trafficking Abstract Eukaryotic cells maintain. Unbalanced fission leads to mitochondrial fragmentation, and un- balanced fusion leads to mitochondrial

Chan, David

185

"50" Years of Fusion Research Fusion Innovation Research and Energy  

E-print Network

"50" Years of Fusion Research Dale Meade Fusion Innovation Research and Energy® Princeton, NJ." John Holdren @MIT, April, 2009 #12;3 #12;Toroidal Magnetic Confinement (1940s-early 50s)g ( y ) · 1940s on a ski lift, and makes proposal to AEC ($50k)-initiates Project Matterhorn at Princeton.p p ( ) j · 1950s

186

EDITORIAL: The Nuclear Fusion Award The Nuclear Fusion Award  

NASA Astrophysics Data System (ADS)

The Nuclear Fusion Award ceremony for 2009 and 2010 award winners was held during the 23rd IAEA Fusion Energy Conference in Daejeon. This time, both 2009 and 2010 award winners were celebrated by the IAEA and the participants of the 23rd IAEA Fusion Energy Conference. The Nuclear Fusion Award is a paper prize to acknowledge the best distinguished paper among the published papers in a particular volume of the Nuclear Fusion journal. Among the top-cited and highly-recommended papers chosen by the Editorial Board, excluding overview and review papers, and by analyzing self-citation and non-self-citation with an emphasis on non-self-citation, the Editorial Board confidentially selects ten distinguished papers as nominees for the Nuclear Fusion Award. Certificates are given to the leading authors of the Nuclear Fusion Award nominees. The final winner is selected among the ten nominees by the Nuclear Fusion Editorial Board voting confidentially. 2009 Nuclear Fusion Award nominees For the 2009 award, the papers published in the 2006 volume were assessed and the following papers were nominated, most of which are magnetic confinement experiments, theory and modeling, while one addresses inertial confinement. Sabbagh S.A. et al 2006 Resistive wall stabilized operation in rotating high beta NSTX plasmas Nucl. Fusion 46 635-44 La Haye R.J. et al 2006 Cross-machine benchmarking for ITER of neoclassical tearing mode stabilization by electron cyclotron current drive Nucl. Fusion 46 451-61 Honrubia J.J. et al 2006 Three-dimensional fast electron transport for ignition-scale inertial fusion capsules Nucl. Fusion 46 L25-8 Ido T. et al 2006 Observation of the interaction between the geodesic acoustic mode and ambient fluctuation in the JFT-2M tokamak Nucl. Fusion 46 512-20 Plyusnin V.V. et al 2006 Study of runaway electron generation during major disruptions in JET Nucl. Fusion 46 277-84 Pitts R.A. et al 2006 Far SOL ELM ion energies in JET Nucl. Fusion 46 82-98 Berk H.L. et al 2006 Explanation of the JET n = 0 chirping mode Nucl. Fusion 46 S888-97 Urano H. et al 2006 Confinement degradation with beta for ELMy HH-mode plasmas in JT-60U tokamak Nucl. Fusion 46 781-7 Izzo V.A. et al 2006 A numerical investigation of the effects of impurity penetration depth on disruption mitigation by massive high-pressure gas jet Nucl. Fusion 46 541-7 Inagaki S. et al 2006 Comparison of transient electron heat transport in LHD helical and JT-60U tokamak plasmas Nucl. Fusion 46 133-41 Watanabe T.-H. et al 2006 Velocity-space structures of distribution function in toroidal ion temperature gradient turbulence Nucl. Fusion 46 24-32 2010 Nuclear Fusion Award nominees For the 2010 award, the papers published in the 2007 volume were assessed and the following papers were nominated, all of which are magnetic confinement experiments and theory. Rice J.E. et al 2007 Inter-machine comparison of intrinsic toroidal rotation in tokamaks Nucl. Fusion 47 1618-24 Lipschultz B. et al 2007 Plasma-surface interaction, scrape-off layer and divertor physics: implications for ITER Nucl. Fusion 47 1189-205 Loarer T. et al 2007 Gas balance and fuel retention in fusion devices Nucl. Fusion 47 1112-20 Garcia O.E et al 2007 Fluctuations and transport in the TCV scrape-off layer Nucl. Fusion 47 667-76 Zonca F. et al 2007 Electron fishbones: theory and experimental evidence Nucl. Fusion 47 1588-97 Maggi C.F. et al 2007 Characteristics of the H-mode pedestal in improved confinement scenarios in ASDEX Upgrade, DIII-D, JET and JT-60U Nucl. Fusion 47 535-51 Yoshida M. et al 2007 Momentum transport and plasma rotation profile in toroidal direction in JT-60U L-mode plasmas Nucl. Fusion 47 856-63 Zohm H. et al 2007 Control of MHD instabilities by ECCD: ASDEX Upgrade results and implications for ITER Nucl. Fusion 47 228-32 Snyder P.B. et al 2007 Stability and dynamics of the edge pedestal in the low collisionality regime: physics mechanisms for steady-state ELM-free operation Nucl. Fusion 47 961-8 Urano H. et al 2007 H-mode pedestal structure in the variation of toroidal rotation and toroidal f

Kikuchi, M.

2011-01-01

187

Culham Centre for Fusion Energy Fusion -A clean future  

E-print Network

supplies of fossil fuels mean that we need to find new, cleaner ways of powering the planet. Nuclear fusion of producing our energy. Fossil fuels bring atmospheric pollution and the prospect of climate change of fusion fuel produces the same amount of energy as 10,000,000 kilograms of fossil fuel; · An inherently

188

Reflections on Fusion's History and Implications for Fusion's Future*  

E-print Network

the Second World War. Over these past 50 years, great progress has been made in this long journey, a journey" to take advantage of a major opportunity. The fusion energy sciences community likewise should take great;3 Yet despite these successes, there is still a long way to go before we achieve a practical fusion

189

The future of fusion  

NASA Astrophysics Data System (ADS)

The population of the world is increasing, mainly in the developing world, and is projected to saturate within about 100 years at up to twice the present population of 6 billion people (Bos et al., World Population Projections: 1994-95 Edition, Published for the World Bank). Studies (Goldemberg and Johansson (Eds.), Energy as an Instrument for Socio-Economic Development United Nations Development Programme, New York, 1995, p. 9; United Nations Statistical Yearbooks, 10th issue; 1965; 20th issue; 1975, 22nd issue, 1977; 32nd issue, 1987; and 39th issue 1994, United Nations Publications; Sheffield, J. Technol. Forecasting Social Change 59 (1998) 55.) show that, historically, the population growth rate has varied inversely as the annual per capita energy use in most parts of the developing world, where per capita energy use is typically less than 1 t of oil equivalent energy per year. However, in areas with more than 2-3 t of oil equivalent of energy use per year per person, the growth rate is around zero. If this trend continues, a stable world population will require, allowing for energy efficiency improvements, some 2-3 times the present annual energy use. There is an abundance of energy in the world both exploited and potential to meet this need - fossil, fission, and renewables - but it is not evenly distributed, some are costly, and there are issues of environmental pollution in present use, that may limit use. Fusion energy is a potential longer-term source with attractive environmental features. It is the least-developed energy option and still faces a challenging development path, but there are many areas of the world that would benefit hugely from its deployment from the later part of the 21st century onward, and it is important to consider how it might be deployed. Most fusion power plant options considered today show an economy of scale, owing to the fixed distance needed for shielding fusion neutrons, tritium breeding and handling the heat loads. One interesting approach is to use the power plant to co-produce electricity and hydrogen to facilitate the introduction of lower cost of electricity, multi-gigawatt power plants (Sheffield et al., A study of options for the deployment of large fusion power plants, 2000, to be published).

Sheffield, John

2001-05-01

190

Physics of Fusion Welding  

NASA Technical Reports Server (NTRS)

Applicabilities and limitations of three techniques analyzed. NASA technical memorandum discusses physics of electron-beam, gas/ tungsten-arc, and laser-beam welding. From comparison of capabilities and limitations of each technique with regard to various welding conditions and materials, possible to develop criteria for selecting best welding technique in specific application. All three techniques classified as fusion welding; small volume of workpiece melted by intense heat source. Heat source moved along seam, leaving in wake solid metal that joins seam edges together.

Nunes, A. C., Jr.

1986-01-01

191

Fission and Fusion Game  

NSDL National Science Digital Library

In this activity, students play a board game where they learn the characteristics of and differences between fission and fusion, as well as the real world applications of these energy-releasing reactions. Reproducible game cards and and game board are included in the resource. The investigation supports material presented in chapter 3, "What Heats the Earth's Interior?" in the textbook, Energy flow, part of the Global System Science, an interdisciplinary course for high school students that emphasizes how scientists from a wide variety of fields work together to understand significant problems of global impact.

192

The modified Lapidus fusion.  

PubMed

Due to its proximal correction site and long lever arm, the Lapidus fusion, modified or not, is a powerful technique to correct hallux valgus deformities. The disadvantages are a high complication rate and a long postoperative rehabilitation period. It is only performed in 5% to 10% of all hallux valgus deformity corrections but remains, however, an important procedure, especially in moderate to severe deformities with intermetatarsal angles more than 14°, hypermobility of the first ray, arthritis of the first tarsometatarsal joint, and recurrent deformities. This article provides an overview of the procedure with special focus on the surgical technique. PMID:24878411

Schmid, Timo; Krause, Fabian

2014-06-01

193

Enhanced image capture through fusion  

Microsoft Academic Search

The authors present an extension to the pyramid approach to image fusion. The modifications address problems that were encountered with past implementations of pyramid-based fusion. In particular, the modifications provide greater shift invariance and immunity to video noise, and provide at least a partial solution to the problem of combining components that have roughly equal salience but opposite contrasts. The

Peter J. Burt; Raymond J. Kolczynski

1993-01-01

194

Cellulose binding domain fusion proteins  

DOEpatents

A cellulose binding domain (CBD) having a high affinity for crystalline cellulose and chitin is disclosed, along with methods for the molecular cloning and recombinant production. Fusion products comprising the CBD and a second protein are likewise described. A wide range of applications are contemplated for both the CBD and the fusion products, including drug delivery, affinity separations, and diagnostic techniques. 16 figs.

Shoseyov, O.; Yosef, K.; Shpiegl, I.; Goldstein, M.A.; Doi, R.H.

1998-02-17

195

Cellulose binding domain fusion proteins  

DOEpatents

A cellulose binding domain (CBD) having a high affinity for crystalline cellulose and chitin is disclosed, along with methods for the molecular cloning and recombinant production thereof. Fusion products comprising the CBD and a second protein are likewise described. A wide range of applications are contemplated for both the CBD and the fusion products, including drug delivery, affinity separations, and diagnostic techniques.

Shoseyov, Oded (Karmey Yosef, IL); Shpiegl, Itai (Rehovot, IL); Goldstein, Marc A. (Davis, CA); Doi, Roy H. (Davis, CA)

1998-01-01

196

Fusion algebra of critical percolation  

E-print Network

We present an explicit conjecture for the chiral fusion algebra of critical percolation considering Virasoro representations with no enlarged or extended symmetry algebra. The representations we take to generate fusion are countably infinite in number. The ensuing fusion rules are quasi-rational in the sense that the fusion of a finite number of these representations decomposes into a finite direct sum of these representations. The fusion rules are commutative, associative and exhibit an sl(2) structure. They involve representations which we call Kac representations of which some are reducible yet indecomposable representations of rank 1. In particular, the identity of the fusion algebra is a reducible yet indecomposable Kac representation of rank 1. We make detailed comparisons of our fusion rules with the recent results of Eberle-Flohr and Read-Saleur. Notably, in agreement with Eberle-Flohr, we find the appearance of indecomposable representations of rank 3. Our fusion rules are supported by extensive numerical studies of an integrable lattice model of critical percolation. Details of our lattice findings and numerical results will be presented elsewhere.

Jorgen Rasmussen; Paul A. Pearce

2007-08-08

197

Fusion Policy Advisory Committee (FPAC)  

SciTech Connect

This document is the final report of the Fusion Policy Advisory Committee. The report conveys the Committee's views on the matters specified by the Secretary in his charge and subsequent letters to the Committee, and also satisfies the provisions of Section 7 of the Magnetic Fusion Energy Engineering Act of 1980, Public Law 96-386, which require a triennial review of the conduct of the national Magnetic Fusion Energy program. Three sub-Committee's were established to address the large number of topics associated with fusion research and development. One considered magnetic fusion energy, a second considered inertial fusion energy, and the third considered issues common to both. For many reasons, the promise of nuclear fusion as a safe, environmentally benign, and affordable source of energy is bright. At the present state of knowledge, however, it is uncertain that this promise will become reality. Only a vigorous, well planned and well executed program of research and development will yield the needed information. The Committee recommends that the US commit to a plan that will resolve this critically important issue. It also outlines the first steps in a development process that will lead to a fusion Demonstration Power Plant by 2025. The recommended program is aggressive, but we believe the goal is reasonable and attainable. International collaboration at a significant level is an important element in the plan.

Not Available

1990-09-01

198

The status of cold fusion  

NASA Astrophysics Data System (ADS)

This report attempts to update the status of the phenomenon of cold fusion. The new field is continuing to grow as a variety of nuclear reactions are discovered to occur in a variety of chemical environments at modest temperatures. However, it must be cautioned that most scientists consider cold fusion as something akin to UFO's, ESP, and numerology.

Storms, E.

199

Data fusion qualitative sensitivity analysis  

SciTech Connect

Pacific Northwest Laboratory was tasked with testing, debugging, and refining the Hanford Site data fusion workstation (DFW), with the assistance of Coleman Research Corporation (CRC), before delivering the DFW to the environmental restoration client at the Hanford Site. Data fusion is the mathematical combination (or fusion) of disparate data sets into a single interpretation. The data fusion software used in this study was developed by CRC. The data fusion software developed by CRC was initially demonstrated on a data set collected at the Hanford Site where three types of data were combined. These data were (1) seismic reflection, (2) seismic refraction, and (3) depth to geologic horizons. The fused results included a contour map of the top of a low-permeability horizon. This report discusses the results of a sensitivity analysis of data fusion software to variations in its input parameters. The data fusion software developed by CRC has a large number of input parameters that can be varied by the user and that influence the results of data fusion. Many of these parameters are defined as part of the earth model. The earth model is a series of 3-dimensional polynomials with horizontal spatial coordinates as the independent variables and either subsurface layer depth or values of various properties within these layers (e.g., compression wave velocity, resistivity) as the dependent variables.

Clayton, E.A.; Lewis, R.E.

1995-09-01

200

Plasma Physics for Nuclear Fusion  

Microsoft Academic Search

The book focuses on the properties of gaseous plasmas needed in the attainment of controlled fusion reactions. The first five chapters develop the fundamentals of plasma physics and present the conditions of nuclear fusion reactions. The next four provide a magnetohydrodynamic description of plasmas, followed by four chapters that explain wave phenomena and instabilities by means of a kinetic model.

K. Miyamoto; Robert L. Dewar

1980-01-01

201

Journal of Fusion Energy, Vol. 18, No. 4, 1999 Report of the FEAC Inertial Fusion Energy Review Panel  

E-print Network

Journal of Fusion Energy, Vol. 18, No. 4, 1999 Report of the FEAC Inertial Fusion Energy Review. S. Department of Energy Fusion Energy Advisory Committee (FEAC) review of its Inertial Fusion Energy of California at San Diego. KEY WORDS: Fusion; fusion science; fusion energy; inertial fusion energy. I. SUMMARY

Abdou, Mohamed

202

Utility requirements for fusion  

SciTech Connect

This report describes work done and results obtained during performance of Task 1 of a study of Utility Requirements and Criteria for Fusion Options. The work consisted of developing a list of utility requirements for fusion optics containing definition of the requirements and showing their relative importance to the utility industry. The project team members developed a preliminary list which was refined by discussions and literature searches. The refined list was recast as a questionnaire which was sent to a substantial portion of the utility industry in this country. Forty-three questionnaire recipients responded including thirty-two utilities. A workshop was held to develop a revised requirements list using the survey responses as a major input. The list prepared by the workshop was further refined by a panel consisting of vice presidents of the three project team firms. The results of the study indicate that in addition to considering the cost of energy for a power plant, utilities consider twenty-three other requirements. Four of the requirements were judged to be vital to plant acceptability: Plant Capital Cost, Financial Liability, Plant Safety and Licensability.

Vondrasek, R.J.

1982-02-01

203

Activity : Fusion Reactions  

NSDL National Science Digital Library

This activity gives students an opportunity to learn about the elements created in the cores of high-mass stars by fusion reactions. They will discover that all stars start by burning hydrogen and end up creating many heavier elements inside their cores, elements that will be released into space when it dies in a supernova explosion. Students associate a layer with an element that is being produced by the high-mass star. This will illustrate that as the temperature of the star increases with depth, the ash of each burning stage becomes the fuel for the next stage. Surrounding the core of iron nuclei is a layer of silicon fusion, then magnesium, then neon, then oxygen, then carbon, then helium, and lastly, in the relatively cool periphery of the core, hydrogen fuses into helium. Students will draw their own version of the onion-like nature of the core of a star based on the model and explain the process that occurs at each layer.

2007-12-12

204

Utility requirements for fusion  

NASA Astrophysics Data System (ADS)

Work done and results obtained during performance of Task 1 of a study of Utility Requirements and Criteria for Fusion Options are described. The work consisted of developing a list of utility requirements for fusion optics containing definition of the requirements and showing their relative importance to the utility industry. The project team members developed a preliminary list which was refined by discussions and literature searches. The refined list was recast as a questionnaire which was sent to a substantial portion of the utility industry in this country. Forty-three questionnaire recipients responded including thirty-two utilities. A workshop was held to develop a revised requirements list using the survey responses as a major input. The list prepared by the workshop was further refined by a panel consisting of vice presidents of the three project team firms. The results of the study indicate that in addition to considering the cost of energy for a power plant, utilities consider twenty-three other requirements. Four of the requirements were judged to be vital to plant acceptability: Plant Capital Cost, Financial Liability, Plant Safety and Licensability.

Vondrasek, R. J.

1982-02-01

205

Inertial confinement fusion  

SciTech Connect

This issue of the ICF Quarterly contains seven articles that describe recent progress in Lawrence Livermore National Laboratory's ICF program. The Department of Energy recently initiated an effort to design a 1--2 MJ glass laser, the proposed National Ignition Facility (NIF). These articles span various aspects of a program which is aimed at moving forward toward such a facility by continuing to use the Nova laser to gain understanding of NIF-relevant target physics, by developing concepts for an NIF laser driver, and by envisioning a variety of applications for larger ICF facilities. This report discusses research on the following topics: Stimulated Rotational Raman Scattering in Nitrogen; A Maxwell Equation Solver in LASNEX for the Simulation of Moderately Intense Ultrashort Pulse Experiments; Measurements of Radial Heat-Wave Propagation in Laser-Produced Plasmas; Laser-Seeded Modulation Growth on Directly Driven Foils; Stimulated Raman Scattering in Large-Aperture, High-Fluence Frequency-Conversion Crystals; Fission Product Hazard Reduction Using Inertial Fusion Energy; Use of Inertial Confinement Fusion for Nuclear Weapons Effects Simulations.

Powers, L.; Condouris, R.; Kotowski, M.; Murphy, P.W. (eds.)

1992-01-01

206

Information integration for data fusion  

SciTech Connect

Data fusion has been identified by the Department of Defense as a critical technology for the U.S. defense industry. Data fusion requires combining expertise in two areas - sensors and information integration. Although data fusion is a rapidly growing area, there is little synergy and use of common, reusable, and/or tailorable objects and models, especially across different disciplines. The Laboratory-Directed Research and Development project had two purposes: to see if a natural language-based information modeling methodology could be used for data fusion problems, and if so, to determine whether this methodology would help identify commonalities across areas and achieve greater synergy. The project confirmed both of the initial hypotheses: that the natural language-based information modeling methodology could be used effectively in data fusion areas and that commonalities could be found that would allow synergy across various data fusion areas. The project found five common objects that are the basis for all of the data fusion areas examined: targets, behaviors, environments, signatures, and sensors. Many of the objects and the specific facts related to these objects were common across several areas and could easily be reused. In some cases, even the terminology remained the same. In other cases, different areas had their own terminology, but the concepts were the same. This commonality is important with the growing use of multisensor data fusion. Data fusion is much more difficult if each type of sensor uses its own objects and models rather than building on a common set. This report introduces data fusion, discusses how the synergy generated by this LDRD would have benefited an earlier successful project and contains a summary information model from that project, describes a preliminary management information model, and explains how information integration can facilitate cross-treaty synergy for various arms control treaties.

Bray, O.H.

1997-01-01

207

LiWall Fusion - The New Concept of Magnetic Fusion  

SciTech Connect

Utilization of the outstanding abilities of a liquid lithium layer in pumping hydrogen isotopes leads to a new approach to magnetic fusion, called the LiWall Fusion. It relies on innovative plasma regimes with low edge density and high temperature. The approach combines fueling the plasma by neutral injection beams with the best possible elimination of outside neutral gas sources, which cools down the plasma edge. Prevention of cooling the plasma edge suppresses the dominant, temperature gradient related turbulence in the core. Such an approach is much more suitable for controlled fusion than the present practice, relying on high heating power for compensating essentially unlimited turbulent energy losses.

L.E. Zakharov

2011-01-12

208

Status report on fusion research  

NASA Astrophysics Data System (ADS)

At the beginning of the twenty-first century mankind is faced with the serious problem of meeting the energy demands of a rapidly industrializing population around the globe. This, against the backdrop of fast diminishing fossil fuel resources (which have been the main source of energy of the last century) and the increasing realization that the use of fossil fuels has started to adversely affect our environment, has greatly intensified the quest for alternative energy sources. In this quest, fusion has the potential to play a very important role and we are today at the threshold of realizing net energy production from controlled fusion experiments. Fusion is, today, one of the most promising of all alternative energy sources because of the vast reserves of fuel, potentially lasting several thousands of years and the possibility of a relatively 'clean' form of energy, as required for use in concentrated urban industrial settings, with minimal long term environmental implications. The last decade and a half has seen unprecedented advances in controlled fusion experiments with the discovery of new regimes of operations in experiments, production of 16 MW of fusion power and operations close to and above the so-called 'break-even' conditions. A great deal of research has also been carried out in analysing various socio-economic aspects of fusion energy. This paper briefly reviews the various aspects and achievements of fusion research all over the world during this period.

Fusion Research Council (IFRC, International

2005-10-01

209

Poxvirus entry and membrane fusion  

SciTech Connect

The study of poxvirus entry and membrane fusion has been invigorated by new biochemical and microscopic findings that lead to the following conclusions: (1) the surface of the mature virion (MV), whether isolated from an infected cell or by disruption of the membrane wrapper of an extracellular virion, is comprised of a single lipid membrane embedded with non-glycosylated viral proteins; (2) the MV membrane fuses with the cell membrane, allowing the core to enter the cytoplasm and initiate gene expression; (3) fusion is mediated by a newly recognized group of viral protein components of the MV membrane, which are conserved in all members of the poxvirus family; (4) the latter MV entry/fusion proteins are required for cell to cell spread necessitating the disruption of the membrane wrapper of extracellular virions prior to fusion; and furthermore (5) the same group of MV entry/fusion proteins are required for virus-induced cell-cell fusion. Future research priorities include delineation of the roles of individual entry/fusion proteins and identification of cell receptors.

Moss, Bernard [Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD 20892-0445 (United States)]. E-mail: bmoss@nih.gov

2006-01-05

210

Fusion Power Demonstration III  

SciTech Connect

This is the third in the series of reports covering the Fusion Power Demonstration (FPD) design study. This volume considers the FPD-III configuration that incorporates an octopole end plug. As compared with the quadrupole end-plugged designs of FPD-I and FPD-II, this octopole configuration reduces the number of end cell magnets and shortens the minimum ignition length of the central cell. The end-cell plasma length is also reduced, which in turn reduces the size and cost of the end cell magnets and shielding. As a contiuation in the series of documents covering the FPD, this report does not stand alone as a design description of FPD-III. Design details of FPD-III subsystems that do not differ significantly from those of the FPD-II configuration are not duplicated in this report.

Lee, J.D. (ed.)

1985-07-01

211

Fusion pumped laser  

DOEpatents

Apparatus is provided for generating energy in the form of laser radiation. A tokamak fusion reactor is provided for generating a long, or continuous, pulse of high-energy neutrons. The tokamak design provides a temperature and a magnetic field which is effective to generate a neutron flux of at least 10.sup.15 neutrons/cm.sup.2.s. A conversion medium receives neutrons from the tokamak and converts the high-energy neutrons to an energy source with an intensity and an energy effective to excite a preselected lasing medium. The energy source typically comprises fission fragments, alpha particles, and radiation from a fission event. A lasing medium is provided which is responsive to the energy source to generate a population inversion which is effective to support laser oscillations for generating output radiation.

Pappas, Daniel S. (Los Alamos, NM)

1989-01-01

212

Fusion pumped light source  

DOEpatents

Apparatus is provided for generating energy in the form of light radiation. A fusion reactor is provided for generating a long, or continuous, pulse of high-energy neutrons. The neutron flux is coupled directly with the lasing medium. The lasing medium includes a first component selected from Group O of the periodic table of the elements and having a high inelastic scattering cross section. Gamma radiation from the inelastic scattering reactions interacts with the first component to excite the first component, which decays by photon emission at a first output wavelength. The first output wavelength may be shifted to a second output wavelength using a second liquid component responsive to the first output wavelength. The light outputs may be converted to a coherent laser output by incorporating conventional optics adjacent the laser medium.

Pappas, Daniel S. (Los Alamos, NM)

1989-01-01

213

Particle beam fusion  

NASA Astrophysics Data System (ADS)

This report summarizes the progress on the pulsed power approach to inertial confinement fusion. In 1989, the authors achieved a proton focal intensity of 5 TW/sq cm on PBFA-2 in a 15-cm-radius applied magnetic-field (applied-B) ion diode. This is an improvement by a factor of 4 compared to previous PBFA-2 experiments. They completed development of the three-dimensional (3-D), electromagnetic, particle-in-cell code QUICKSILVER and obtained the first 3-D simulations of an applied-B ion diode. The simulations, together with analytic theory, suggest that control of electromagnetic instabilities could reduce ion divergence. In experiments using a lithium fluoride source, they delivered 26 kJ of lithium energy to the diode axis. Rutherford-scattered ion diagnostics have been developed and tested using a conical foil located inside the diode. They can now obtain energy density profiles by using range filters and recording ion images on nuclear track recording film. Timing uncertainties in power flow experiments on PBFA-2 have been reduced by a factor of 5. They are investigating three plasma opening switches that use magnetic fields to control and confine the injected plasma. These new switches provide better power flow than the standard plasma erosion switch. Advanced pulsed-power fusion drivers will require extraction-geometry applied-B ion diodes. During this reporting period, progress was made in evaluating the generation, transport, and focus of multiple ion beams in an extraction geometry and in assessing the probable damage to a target chamber first wall.

Sweeney, M. A.

1994-08-01

214

Soldier systems sensor fusion  

NASA Astrophysics Data System (ADS)

This paper addresses sensor fusion and its applications in emerging Soldier Systems integration and the unique challenges associated with the human platform. Technology that,provides the highest operational payoff in a lightweight warrior system must not only have enhanced capabilities, but have low power components resulting in order of magnitude reductions coupled with significant cost reductions. These reductions in power and cost will be achieved through partnership with industry and leveraging of commercial state of the art advancements in microelectronics and power sources. As new generation of full solution fire control systems (to include temperature, wind and range sensors) and target acquisition systems will accompany a new generation of individual combat weapons and upgrade existing weapon systems. Advanced lightweight thermal, IR, laser and video senors will be used for surveillance, target acquisition, imaging and combat identification applications. Multifunctional sensors will provide embedded training features in combat configurations allowing the soldier to 'train as he fights' without the traditional cost and weight penalties associated with separate systems. Personal status monitors (detecting pulse, respiration rate, muscle fatigue, core temperature, etc.) will provide commanders and highest echelons instantaneous medical data. Seamless integration of GPS and dead reckoning (compass and pedometer) and/or inertial sensors will aid navigation and increase position accuracy. Improved sensors and processing capability will provide earlier detection of battlefield hazards such as mines, enemy lasers and NBC (nuclear, biological, chemical) agents. Via the digitized network the situational awareness database will automatically be updated with weapon, medical, position and battlefield hazard data. Soldier Systems Sensor Fusion will ultimately establish each individual soldier as an individual sensor on the battlefield.

Brubaker, Kathryne M.

1998-08-01

215

Fusion Lecture Summary Eugene S. Evans  

E-print Network

Fusion Lecture Summary Eugene S. Evans Physics H190, University of California, Berkeley March 31. Evans (2010) Fusion Lecture Summary March 31, 2010 1 / 15 #12;Outline 1 Overview of NIF Specifications Timeline Goals 2 Inertial Confinement Fusion (ICF) 3 Science at NIF 4 Fusion and the Future Laser Inertial

Budker, Dmitry

216

2002 Fusion Summer Study Executive Summary  

E-print Network

2002 Fusion Summer Study Executive Summary 31 July 2002 #12;page 2 of 15 2002 Fusion Summer Study Executive Summary The 2002 Fusion Summer Study was conducted from July 8-19, 2002, in Snowmass, CO, and carried out a critical assessment of major next-steps in the fusion energy sciences program in both

217

Fusion Development Path Panel Preliminary Report  

E-print Network

Fusion Development Path Panel Preliminary Report Summary for NRC BPAC Panel (Focus on MFE of a demonstration power plant in approximately 35 years. The plan should recognize the capabilities of all fusion facilities around the world, and include both magnetic fusion energy (MFE) and inertial fusion energy (IFE

218

ERDA-76/110/l FUSION POWER  

E-print Network

of fusion reactors will occur through a developing fusion vendor industry working with Government, national promising approach to fusion and is closer to achieving a demonstration reactor for commer- cial applicationERDA-76/110/l UC-20 FUSION POWER BY MAGNETIC CONFINEMENT PROGRAMPLAN VOLUME I SUMMARY JULY 1976

219

White Paper on Magnetic Fusion Program Strategies  

E-print Network

production of over IO MW of fusion power in the Tokamak Fusion Test Reactor at Princeton University of the international fusion program, the International Thermonuclear Experimental Reactor (ITER), is now halfwayWhite Paper on Magnetic Fusion Program Strategies Prepared for The President's Committee

220

Fusion Energy Sciences Advisory Committee Strategic Planning  

E-print Network

, advanced materials that can withstand the harsh environment inside a fusion reactor, and safe regeneration of the fusion fuel from within the reactor. Throughout its history, the quest for fusion has been a globalD R A F T Fusion Energy Sciences Advisory Committee Report on Strategic Planning: Priorities

221

Safety aspects of fusion power plants  

Microsoft Academic Search

This special issue of Nuclear Fusion contains 13 informative papers that were initially presented at the 8th IAEA Technical Meeting on Fusion Power Plant Safety held in Vienna, Austria, 10–13 July 2006.Following recommendation from the International Fusion Research Council, the IAEA organizes Technical Meetings on Fusion Safety with the aim to bring together experts to discuss the ongoing work, share

B. N. Kolbasov

2007-01-01

222

EDITORIAL: Safety aspects of fusion power plants  

Microsoft Academic Search

This special issue of Nuclear Fusion contains 13 informative papers that were initially presented at the 8th IAEA Technical Meeting on Fusion Power Plant Safety held in Vienna, Austria, 10-13 July 2006. Following recommendation from the International Fusion Research Council, the IAEA organizes Technical Meetings on Fusion Safety with the aim to bring together experts to discuss the ongoing work,

B. N. Kolbasov

2007-01-01

223

Spectral Edge Image Fusion: Theory and Applications  

E-print Network

-infrared images, and colour visualisation of MRI Diffusion-Tensor imaging. Keywords: Image fusion; gradient such as a colour monitor. This process is termed image fusion. Thus, in the image fusion problem, there can be 10Spectral Edge Image Fusion: Theory and Applications David Connah1 , Mark S. Drew2 , Graham D

Drew, Mark S.

224

Fusion Energy: Visions of the Future  

E-print Network

Scale, Terrapower, Areva Nat'l Ignition Facility, Iter, General Fusion TriAlpha, Polywell, LPP #12;DeuteriumFusion Energy: Visions of the Future Dec. 10-11, 2013 FOCUS FUSION Cheap, Clean, Safe & Unlimited Energy #12;Controlled Nuclear Fusion With a Dense Plasma Focus Device Running on Aneutronic Fuel What

225

Palmprint identification using feature-level fusion  

Microsoft Academic Search

In this paper, we propose a feature-level fusion approach for improving the efficiency of palmprint identification. Multiple elliptical Gabor filters with different orientations are employed to extract the phase information on a palmprint image, which is then merged according to a fusion rule to produce a single feature called the Fusion Code. The similarity of two Fusion Codes is measured

Adams Kong; David Zhang; Mohamed Kamel

226

Palmprint identification using feature-level fusion  

Microsoft Academic Search

Abstract In this paper, we propose a feature-level fusion approach for improving the efficiency of palmprint identification. Multiple elliptical Gabor filters with different orientations are employed to extract the phase information on a palmprint image, which is then merged according to a fusion rule to produce a single feature called the Fusion Code. The similarity of two Fusion Codes is

Adams Wai-kin Kong; David Zhang; Mohamed Kamel

2006-01-01

227

Improved Image Fusion Using Balanced Multiwavelets  

E-print Network

be discarded. Image fusion can take place at the signal, pixel, feature, transform, and symbol level. Fusion of the important image features such as edges in the source images. The fusion process will produce a fused imageImproved Image Fusion Using Balanced Multiwavelets Lahouari Ghouti, Ahmed Bouridane and Mohammad K

Ghouti, Lahouari

228

Detecting Sensor Failures in a Multi-Sensor Data Fusion SystemData Fusion System  

E-print Network

Detecting Sensor Failures in a Multi-Sensor Data Fusion SystemData Fusion System Thomas Pfister 21 · Introduction · Realization sensor fusion · Failure detection methods · Simulation results Detecting Sensor Failures in a Multi-Sensor Data Fusion System #12;Introduction Multi-Sensor Data Fusion · Problem

Berns, Karsten

229

FUSION FRAMES AND THEORETICAL APPLICATIONS: FOR THE FUSION FRAME WEB PAGE  

E-print Network

FUSION FRAMES AND THEORETICAL APPLICATIONS: FOR THE FUSION FRAME WEB PAGE PETER G. CASAZZA The deepest and most difficult question in Fusion Frame Theory is the construction of fusion frames with added that they do not show how to construct the frames. Recently, Casazza and Fickus [4] have developed a Fusion

Casazza, Pete

230

Influenza Virus-Membrane Fusion Triggered by Proton Uncaging for Single Particle Studies of Fusion Kinetics  

E-print Network

Influenza Virus-Membrane Fusion Triggered by Proton Uncaging for Single Particle Studies of Fusion for studying membrane fusion, focusing on influenza virus fusion to lipid bilayers, which provides high temporal resolution through the rapid and coordinated initiation of individual virus fusion events. Each

Daniel, Susan

231

91039: Magnetic fusion: The DOE fusion energy sciences program  

SciTech Connect

For over 40 years, the U.S. has been trying to harness the energy source of the hydrogen bomb to produce electricity. Controlling fusion, the nuclear reaction that powers the sun, requires confining and heating deuterium and tritium nuclei to the point where they will collide (a D-T reaction) producing nuclear energy in a sustained, regulated way. One path to this goal, called magnetic fusion energy (MFE), is to use very strong magnetic fields to confine a deuterium and tritium plasma while heating it to fusion temperatures. The potential benefits from fusion are enormous. The fuel resources are vast. Radioactive waste would be generated from a D-T reaction, but the long term buildup would be orders of magnitude less than that of a comparable fission reactor.

Rowberg, R.E.

1997-01-24

232

Fusion materials irradiations at MaRIE's fission fusion facility  

SciTech Connect

Los Alamos National Laboratory's proposed signature facility, MaRIE, will provide scientists and engineers with new capabilities for modeling, synthesizing, examining, and testing materials of the future that will enhance the USA's energy security and national security. In the area of fusion power, the development of new structural alloys with better tolerance to the harsh radiation environments expected in fusion reactors will lead to improved safety and lower operating costs. The Fission and Fusion Materials Facility (F{sup 3}), one of three pillars of the proposed MaRIE facility, will offer researchers unprecedented access to a neutron radiation environment so that the effects of radiation damage on materials can be measured in-situ, during irradiation. The calculated radiation damage conditions within the F{sup 3} match, in many respects, that of a fusion reactor first wall, making it well suited for testing fusion materials. Here we report in particular on two important characteristics of the radiation environment with relevancy to radiation damage: the primary knock-on atom spectrum and the impact of the pulse structure of the proton beam on temporal characteristics of the atomic displacement rate. With respect to both of these, analyses show the F{sup 3} has conditions that are consistent with those of a steady-state fusion reactor first wall.

Pitcher, Eric J [Los Alamos National Laboratory

2010-10-06

233

Multimodal fusion for multimedia analysis: a survey  

Microsoft Academic Search

This survey aims at providing multimedia researchers with a state-of-the-art overview of fusion strategies, which are used\\u000a for combining multiple modalities in order to accomplish various multimedia analysis tasks. The existing literature on multimodal\\u000a fusion research is presented through several classifications based on the fusion methodology and the level of fusion (feature,\\u000a decision, and hybrid). The fusion methods are described

Pradeep K. AtreyM; M. Anwar Hossain; Abdulmotaleb El-Saddik; Mohan S. Kankanhalli

2010-01-01

234

Overview of fusion reactor safety  

NASA Astrophysics Data System (ADS)

Use of deuterium-tritium fusion reactors requires examination of several major safety and environmental issues: (1) tritium inventory control; (2) neutron activation of structural materials, fluid streams and reactor hall environment; (3) release of radioactivity from energy sources including lithium spill reactions, superconducting magnet stored energy release, and plasma disruptions; (4) high magnetic and electromagnetic fields associated with fusion reactor superconducting magnets and radio frequency heating devices; and (5) handling and disposal of radioactive waste. Early recognition of potential safety problems with fusion reactors provides the opportunity for improvement in design and materials to eliminate or greatly reduce these problems. With an early start in this endeavor, fusion should be among the lower risk technologies for generation of commercial electrical power.

Cohen, S.; Crocker, J. G.

235

Magnetic fusion 1985: what next  

SciTech Connect

Recent budget reductions for magnetic fusion have led to a re-examination of program schedules and objectives. Faced with delays and postponement of major facilities as previously planned, some have called for a near-term focus on science, others have stressed technology. This talk will suggest a different focus as the keynote for this conference, namely, the applications of fusion. There is no doubt that plasma science is by now mature and fusion technology is at the forefront. This has and will continue to benefit many fields of endeavor, both in actual new discoveries and techniques and in attracting and training scientists and engineers who move on to make significant contributions in science, defense and industry. Nonetheless, however superb the science or how challenging the technology, these are means, not ends. To maintain its support, the magnetic fusion program must also offer the promise of power reactors that could be competitive in the future. At this conference, several new reactor designs will be described that claim to be smaller and economically competitive with fission reactors while retaining the environmental and safety characteristics that are the hallmark of fusion. The American Nuclear Society is an appropriate forum in which to examine these new designs critically, and to stimulate better ideas and improvements. As a preview, this talk will include brief discussions of new tokamak, tandem mirror and reversed field pinch reactor designs to be presented in later sessions. Finally, as a preview of the session on fusion breeders, the talk will explore once again the economic implications of a new nuclear age, beginning with improved fission reactors fueled by fusion breeders, then ultimately evolving to reactors based solely on fusion.

Fowler, T.K.

1985-03-01

236

Inhibition of Hendra Virus Fusion  

Microsoft Academic Search

Hendra virus (HeV) is a recently identified paramyxovirus that is fatal in humans and could be used as an agent of bioterrorism. The HeV receptor-binding protein (G) is required in order for the fusion protein (F) to mediate fusion, and analysis of the triggering\\/activation of HeV F by G should lead to strategies for interfering with this key step in

M. Porotto; P. Carta; M. Fornabaio; O. Greengard; G. E. Kellogg; A. Moscona

2006-01-01

237

Cell Fusion and Tissue Regeneration  

Microsoft Academic Search

\\u000a Cell fusion is a natural process implicated in normal development, immune response, tissue formation, and with a prominent\\u000a role in stem cell plasticity. The discovery that bone marrow stem cells fuse with several cell types, under normal condition\\u000a or after an injury, introduces new possibilities in regenerative medicine and genetic repair. Cell fusion has been shown to\\u000a be implicated in

Manuel Álvarez-Dolado; Magdalena Martínez-Losa

238

Fusion genes in breast cancer  

E-print Network

Fusion genes in breast cancer Elizabeth M. Batty Clare College, University of Cambridge A dissertation submitted to the University of Cambridge in candidature for the degree of Doctor of Philosophy November 2010 ii... is the outcome of work done in collaboration except where specifically indicated in the text. It has not been submitted whole or in part for any other qualification at any other University. iii Summary Fusion genes in breast cancer Elizabeth Batty...

Batty, Elizabeth

2012-02-07

239

Laser fusion monthly -- August 1980  

SciTech Connect

This report documents the monthly progress for the laser fusion research at Lawrence Livermore National Laboratory. First it gives facilities report for both the Shiva and Argus projects. Topics discussed include; laser system for the Nova Project; the fusion experiments analysis facility; optical/x-ray streak camera; Shiva Dante System temporal response; 2{omega}{sub 0} experiment; and planning for an ICF engineering test facility.

Ahlstrom, H.G. [ed.

1980-08-01

240

Proteolytic cleavage of Opa1 stimulates mitochondrial inner membrane fusion and couples fusion to oxidative phosphorylation.  

PubMed

Mitochondrial fusion is essential for maintenance of mitochondrial function. The mitofusin GTPases control mitochondrial outer membrane fusion, whereas the dynamin-related GTPase Opa1 mediates inner membrane fusion. We show that mitochondrial inner membrane fusion is tuned by the level of oxidative phosphorylation (OXPHOS), whereas outer membrane fusion is insensitive. Consequently, cells from patients with pathogenic mtDNA mutations show a selective defect in mitochondrial inner membrane fusion. In elucidating the molecular mechanism of OXPHOS-stimulated fusion, we uncover that real-time proteolytic processing of Opa1 stimulates mitochondrial inner membrane fusion. OXPHOS-stimulated mitochondrial fusion operates through Yme1L, which cleaves Opa1 more efficiently under high OXPHOS conditions. Engineered cleavage of Opa1 is sufficient to mediate inner membrane fusion, regardless of respiratory state. Proteolytic cleavage therefore stimulates the membrane fusion activity of Opa1, and this feature is exploited to dynamically couple mitochondrial fusion to cellular metabolism. PMID:24703695

Mishra, Prashant; Carelli, Valerio; Manfredi, Giovanni; Chan, David C

2014-04-01

241

Kinetic advantage of controlled intermediate nuclear fusion  

SciTech Connect

The dominated process of controlled fusion is to let nuclei gain enough kinetic energy to overcome Coulomb barrier. As a result, a fusion scheme can consider two factors in its design: to increase kinetic energy of nuclei and to alter the Coulomb barrier. Cold Fusion and Hot fusion are all one-factor schemes while Intermediate Fusion is a twofactors scheme. This made CINF kinetically superior. Cold Fusion reduces deuteron-deuteron distance, addressing Coulomb barrier, and Hot Fusion heat up plasma into extreme high temperature, addressing kinetic energy. Without enough kinetic energy made Cold Fusion skeptical. Extreme high temperature made Hot Fusion very difficult to engineer. Because CIFN addresses both factors, CIFN is a more promising technique to be industrialized.

Guo Xiaoming [Physics and Computer Science Department, Wilfrid Laurier University, Waterloo, Ontario, N2L 3C5 (Canada)

2012-09-26

242

Cluster-impact fusion, or beam-contaminant fusion (abstract)  

SciTech Connect

Beuhler, Friedlander, and Friedman (BFF) reported anomalously huge D-D fusion rates while bombarding deuterated targets with (D{sub 2}O){sub {ital N}}{sup +} clusters ({ital N}{similar to}25--1000) accelerated to {approx}325 keV (R. J. Beuhler {ital et} {ital al}., Phys. Rev. Lett. {bold 63}, 1292 (1989); R. J. Beuhler {ital et} {ital al}., J. Phys. Chem. {bold 94}, 7665 (1990)) (i.e., {approx}0.3 keV lab energy for D in (D{sub 2}O){sub 100}{sup +}). However, from our analysis of BFF's fusion product spectra, we conclude that their D lab energy was {similar to}50 keV. Therefore, no gross anomalies exist. Also, from our analysis of the BFF beam-ranging experiments through 500 {mu}g/cm{sup 2} of Au, we conclude that light-ion-beam contaminants (e.g., D{sup +} of order 100 keV) have not been ruled out, and are the probable cause of their fusion reactions. This work was supported by LLNL Subcontract B116798, Department of Energy (DOE) Grant No. DE-FG02-91ER54109, DOE Magnetic Fusion Energy Technology Fellowship Program (D. H. Lo), and DOE Fusion Energy Postdoctoral Research Program (Kevin W. Wenzel).

Lo, D.H.; Petrasso, R.D.; Wenzel, K.W. (Plasma Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States))

1992-10-01

243

Fusion Plasma Theory project summaries  

SciTech Connect

This Project Summary book is a published compilation consisting of short descriptions of each project supported by the Fusion Plasma Theory and Computing Group of the Advanced Physics and Technology Division of the Department of Energy, Office of Fusion Energy. The summaries contained in this volume were written by the individual contractors with minimal editing by the Office of Fusion Energy. Previous summaries were published in February of 1982 and December of 1987. The Plasma Theory program is responsible for the development of concepts and models that describe and predict the behavior of a magnetically confined plasma. Emphasis is given to the modelling and understanding of the processes controlling transport of energy and particles in a toroidal plasma and supporting the design of the International Thermonuclear Experimental Reactor (ITER). A tokamak transport initiative was begun in 1989 to improve understanding of how energy and particles are lost from the plasma by mechanisms that transport them across field lines. The Plasma Theory program has actively-participated in this initiative. Recently, increased attention has been given to issues of importance to the proposed Tokamak Physics Experiment (TPX). Particular attention has been paid to containment and thermalization of fast alpha particles produced in a burning fusion plasma as well as control of sawteeth, current drive, impurity control, and design of improved auxiliary heating. In addition, general models of plasma behavior are developed from physics features common to different confinement geometries. This work uses both analytical and numerical techniques. The Fusion Theory program supports research projects at US government laboratories, universities and industrial contractors. Its support of theoretical work at universities contributes to the office of Fusion Energy mission of training scientific manpower for the US Fusion Energy Program.

Not Available

1993-10-01

244

The Path to Magnetic Fusion Energy  

SciTech Connect

When the possibility of fusion as an energy source for electricity generation was realized in the 1950s, understanding of the plasma state was primitive. The fusion goal has been paced by, and has stimulated, the development of plasma physics. Our understanding of complex, nonlinear processes in plasmas is now mature. We can routinely produce and manipulate 100 million degree plasmas with remarkable finesse, and we can identify a path to commercial fusion power. The international experiment, ITER, will create a burning (self-sustained) plasma and produce 500 MW of thermal fusion power. This talk will summarize the progress in fusion research to date, and the remaining steps to fusion power.

Prager, Stewart (PPPL) [PPPL

2011-05-04

245

Object recognition by active fusion  

NASA Astrophysics Data System (ADS)

Today's computer vision applications often have to deal with multiple, uncertain, and incomplete visual information. In this paper, we apply a new method, termed 'active fusion', to the problem of generic object recognition. Active fusion provides a common framework for active selection and combination of information from multiple sources in order to arrive at a reliable result at reasonable costs. In our experimental setup we use a camera mounted on a 2m by 1.5m x/z-table observing objects placed on a rotating table. Zoom, pan, tilt, and aperture setting of the camera can be controlled by the system. We follow a part-based approach, trying to decompose objects into parts, which are modeled as geons. The active fusion system starts from an initial view of the objects placed on the table and is continuously trying to refine its current object hypotheses by requesting additional views. The implementation of active fusion on the basis of probability theory, Dempster-Shafer's theory of evidence and fuzzy set theory is discussed. First results demonstrating segmentation improvements by active fusion are presented.

Prantl, Manfred; Kopp-Borotschnig, Hermann; Ganster, Harald; Sinclair, David; Pinz, Axel J.

1996-10-01

246

Nuclear Fusion prize laudation Nuclear Fusion prize laudation  

NASA Astrophysics Data System (ADS)

Clean energy in abundance will be of critical importance to the pursuit of world peace and development. As part of the IAEA's activities to facilitate the dissemination of fusion related science and technology, the journal Nuclear Fusion is intended to contribute to the realization of such energy from fusion. In 2010, we celebrated the 50th anniversary of the IAEA journal. The excellence of research published in the journal is attested to by its high citation index. The IAEA recognizes excellence by means of an annual prize awarded to the authors of papers judged to have made the greatest impact. On the occasion of the 2010 IAEA Fusion Energy Conference in Daejeon, Republic of Korea at the welcome dinner hosted by the city of Daejeon, we celebrated the achievements of the 2009 and 2010 Nuclear Fusion prize winners. Steve Sabbagh, from the Department of Applied Physics and Applied Mathematics, Columbia University, New York is the winner of the 2009 award for his paper: 'Resistive wall stabilized operation in rotating high beta NSTX plasmas' [1]. This is a landmark paper which reports record parameters of beta in a large spherical torus plasma and presents a thorough investigation of the physics of resistive wall mode (RWM) instability. The paper makes a significant contribution to the critical topic of RWM stabilization. John Rice, from the Plasma Science and Fusion Center, MIT, Cambridge is the winner of the 2010 award for his paper: 'Inter-machine comparison of intrinsic toroidal rotation in tokamaks' [2]. The 2010 award is for a seminal paper that analyzes results across a range of machines in order to develop a universal scaling that can be used to predict intrinsic rotation. This paper has already triggered a wealth of experimental and theoretical work. I congratulate both authors and their colleagues on these exceptional papers. W. Burkart Deputy Director General Department of Nuclear Sciences and Applications International Atomic Energy Agency, Vienna, Austria References [1] Sabbagh S. et al 2006 Nucl. Fusion 46 635-44 [2] Rice J.E. et al 2007 Nucl. Fusion 47 1618-24

Burkart, W.

2011-01-01

247

(Meeting on fusion reactor materials)  

SciTech Connect

During his visit to the KfK, Karlsruhe, F. W. Wiffen attended the IEA 12th Working Group Meeting on Fusion Reactor Materials. Plans were made for a low-activation materials workshop at Culham, UK, for April 1991, a data base workshop in Europe for June 1991, and a molecular dynamics workshop in the United States in 1991. At the 11th IEA Executive Committee on Fusion Materials, discussions centered on the recent FPAC and Colombo panel review in the United States and EC, respectively. The Committee also reviewed recent progress toward a neutron source in the United States (CWDD) and in Japan (ESNIT). A meeting with D. R. Harries (consultant to J. Darvas) yielded a useful overview of the EC technology program for fusion. Of particular interest to the US program is a strong effort on a conventional ferritic/martensitic steel for fist wall/blanket operation beyond NET/ITER.

Jones, R.H. (Pacific Northwest Lab., Richland, WA (USA)); Klueh, R.L.; Rowcliffe, A.F.; Wiffen, F.W. (Oak Ridge National Lab., TN (USA)); Loomis, B.A. (Argonne National Lab., IL (USA))

1990-11-01

248

Fusion power for space propulsion.  

NASA Technical Reports Server (NTRS)

Principles of operation, interplanetary orbit-to-orbit mission capabilities, technical problems, and environmental safeguards are examined for thermonuclear fusion propulsion systems. Two systems examined include (1) a fusion-electric concept in which kinetic energy of charged particles from the plasma is converted into electric power (for accelerating the propellant in an electrostatic thrustor) by the van de Graaf generator principle and (2) the direct fusion rocket in which energetic plasma lost from the reactor has a suitable amount of added propellant to obtain the optimum exhaust velocity. The deuterium-tritium and the deuterium/helium-3 reactions are considered as suitable candidates, and attention is given to problems of cryogenic refrigeration systems, magnet shielding, and high-energy particle extraction and guidance.

Roth, R.; Rayle, W.; Reinmann, J.

1972-01-01

249

Fusion: Power for the future  

NASA Astrophysics Data System (ADS)

There is a growing recognition that we need an alternative to conventional fossil fuels. Shortages of oil and gas have the potential to cause economic and political instability, and burning fossil fuels can cause environmental damage, as well as being the likeliest cause of global warming. Fusion - the process that powers the sun and stars, has the potential to provide large-scale, safe energy production, without adding to global warming and without the long-term radioactive waste associated with conventional fission power stations. More importantly, within the next 20 years large-scale fusion power production is planned to be demonstrated by the multinational experiment ITER, and a proposed `fast track' to fusion envisages a time-scale of roughly 30 years for a prototype power plant PROTO to be built.

Webster, Anthony J.

2003-03-01

250

Advanced Concepts: Aneutronic Fusion Power and Propulsion  

NASA Technical Reports Server (NTRS)

Aneutronic Fusion for In-Space thrust, power. Clean energy & potential nuclear gains. Fusion plant concepts, potential to use advanced fuels. Methods to harness ionic momentum for high Isp thrust plus direct power conversion into electricity will be presented.

Chapman, John J.

2012-01-01

251

HIV-1 Fusion Peptide Decreases Bending Energy and Promotes Curved Fusion Intermediates  

E-print Network

HIV-1 Fusion Peptide Decreases Bending Energy and Promotes Curved Fusion Intermediates Stephanie in human immunodeficiency virus (HIV) infection is fusion between the viral envelope and the T x-ray scattering is that the bending modulus KC is greatly reduced upon addition of the HIV fusion

Nagle, John F.

252

Towards Hard+Soft Data Fusion: Processing Architecture and Implementation for the Joint Fusion  

E-print Network

Towards Hard+Soft Data Fusion: Processing Architecture and Implementation for the Joint Fusion, Stuart C. Shapiro, Gregory Tauer Center for Multisource Information Fusion State University of New York@buffalo.edu, shapiro@buffalo.edu, gregoryt@buffalo.edu Abstract-- Historically, data fusion has focused on processing

Shapiro, Stuart C.

253

2002 Summer Fusion Study 1 July 19, 2002 2002 Fusion Summer Study  

E-print Network

2002 Summer Fusion Study 1 July 19, 2002 2002 Fusion Summer Study Snowmass Village, CO. July 19, 2002 For Immediate Release Fusion energy shows great promise to contribute to securing the energy leading scientists from the U.S. and international fusion community concluded a two-week forum assessing

254

Science/Fusion Energy Sciences FY 2011 Congressional Budget Fusion Energy Sciences  

E-print Network

Science/Fusion Energy Sciences FY 2011 Congressional Budget Fusion Energy Sciences Funding Profile FY 2010 Current Appropriation FY 2011 Request Fusion Energy Sciences Science 163,479 +57,399 182, Fusion Energy Sciences 394,518b +91,023 426,000 380,000 Public Law Authorizations: Public Law 95

255

Science/Fusion Energy Sciences FY 2007 Congressional Budget Fusion Energy Sciences  

E-print Network

Science/Fusion Energy Sciences FY 2007 Congressional Budget Fusion Energy Sciences Funding Profile Adjustments FY 2006 Current Appropriation FY 2007 Request Fusion Energy Sciences Science,182 Total, Fusion Energy Sciences........... 266,947b 290,550 -2,906 287,644 318,950 Public Law

256

FUSION-3792; No.of Pages15 Fusion Engineering and Design xxx (2006) xxxxxx  

E-print Network

FUSION-3792; No.of Pages15 Fusion Engineering and Design xxx (2006) xxx­xxx Recent progress.07.087 #12;FUSION-3792; No.of Pages15 2 F. Najmabadi, A.R. Raffray / Fusion Engineering and Design xxx (2006) xxx­xxx of any stellarator configuration represents a large number of trade-offs among physics

Raffray, A. René

257

The Heavy Ion Fusion Science Virtual National Laboratory Heavy Ion Fusion*  

E-print Network

target debris, neutron and gamma radiation. (d) Because heavy ions can penetrate metal cases surrounding11/24/2010 The Heavy Ion Fusion Science Virtual National Laboratory 1 Heavy Ion Fusion* B. Grant Logan Heavy Ion Fusion Science Virtual National Laboratory** Fusion Power Associates Annual Meeting

258

Fusion safety regulations in the United States: Progress and trends  

SciTech Connect

This paper explores the issue of regulations as they apply to current and future fusion experimental machines. It addresses fusion regulatory issues, current regulations used for fusion, the Tokamak Fusion Test Reactor experience with regulations, and future regulations to achieve fusion`s safety and environmental potential.

DeLooper, J.

1994-07-01

259

Z-Pinch Fusion Propulsion  

NASA Technical Reports Server (NTRS)

Fusion-based nuclear propulsion has the potential to enable fast interplanetary transportation. Shorter trips are better for humans in the harmful radiation environment of deep space. Nuclear propulsion and power plants can enable high Ispand payload mass fractions because they require less fuel mass. Fusion energy research has characterized the Z-Pinch dense plasma focus method. (1) Lightning is form of pinched plasma electrical discharge phenomena. (2) Wire array Z-Pinch experiments are commonly studied and nuclear power plant configurations have been proposed. (3) Used in the field of Nuclear Weapons Effects (NWE) testing in the defense industry, nuclear weapon x-rays are simulated through Z-Pinch phenomena.

Miernik, Janie

2011-01-01

260

Magnetic fusion commercial power plants  

NASA Astrophysics Data System (ADS)

Toroidal magnetic systems offer the best opportunity to make a commercial fusion power plant. They have, between them, all the features needed; however, no one system yet meets the ideal requirements. The tokamak is the most advanced system, and the proposed International Thermonuclear Experimental Reactor (ITER) and Tokamak Physics Experiment (TPX) will build upon the existing program to prepare for an advanced tokamak demonstration plant. Complementary toroidal systems such as the spherical torus, stellarator, reversed-field pinch, field-reversed configuration, and spheromak offer, between them, potential advantages in each area and should be studied in a balanced fusion development program.

Sheffield, John

1994-09-01

261

Method for vacuum fusion bonding  

DOEpatents

An improved vacuum fusion bonding structure and process for aligned bonding of large area glass plates, patterned with microchannels and access holes and slots, for elevated glass fusion temperatures. Vacuum pumpout of all components is through the bottom platform which yields an untouched, defect free top surface which greatly improves optical access through this smooth surface. Also, a completely non-adherent interlayer, such as graphite, with alignment and location features is located between the main steel platform and the glass plate pair, which makes large improvements in quality, yield, and ease of use, and enables aligned bonding of very large glass structures.

Ackler, Harold D. (Sunnyvale, CA); Swierkowski, Stefan P. (Livermore, CA); Tarte, Lisa A. (Livermore, CA); Hicks, Randall K. (Stockton, CA)

2001-01-01

262

Fusion bonding and alignment fixture  

DOEpatents

An improved vacuum fusion bonding structure and process for aligned bonding of large area glass plates, patterned with microchannels and access holes and slots, for elevated glass fusion temperatures. Vacuum pumpout of all the components is through the bottom platform which yields an untouched, defect free top surface which greatly improves optical access through this smooth surface. Also, a completely non-adherent interlayer, such as graphite, with alignment and location features is located between the main steel platform and the glass plate pair, which makes large improvements in quality, yield, and ease of use, and enables aligned bonding of very large glass structures.

Ackler, Harold D. (Sunnyvale, CA); Swierkowski, Stefan P. (Livermore, CA); Tarte, Lisa A. (Livermore, CA); Hicks, Randall K. (Stockton, CA)

2000-01-01

263

Electromagnetic computations for fusion devices  

SciTech Connect

Among the difficulties in making nuclear fusion a useful energy source, two important ones are producing the magnetic fields needed to drive and confine the plasma, and controlling the eddy currents induced in electrically conducting components by changing fields. All over the world, researchers are developing electromagnetic codes and employing them to compute electromagnetic effects. Ferromagnetic components of a fusion reactor introduce field distortions. Eddy currents are induced in the vacuum vessel, blanket and other torus components of a tokamak when the plasma current disrupts. These eddy currents lead to large forces, and 3-D codes are being developed to study the currents and forces. 35 refs., 6 figs.

Turner, L.R.

1989-09-01

264

Fusion Breeder Program interim report  

SciTech Connect

This interim report for the FY82 Fusion Breeder Program covers work performed during the scoping phase of the study, December, 1981-February 1982. The goals for the FY82 study are the identification and development of a reference blanket concept using the fission suppression concept and the definition of a development plan to further the fusion breeder application. The context of the study is the tandem mirror reactor, but emphasis is placed upon blanket engineering. A tokamak driver and blanket concept will be selected and studied in more detail during FY83.

Moir, R.; Lee, J.D.; Neef, W.

1982-06-11

265

Revisions to the JDL data fusion model  

Microsoft Academic Search

The Joint Directors of Laboratories {(JDL)} Data Fusion Group's Data Fusion Model is the most widely used method for categorizing data fusion-related functions. This model is modified to facilitate the cost-effective development, acquisition, integration and operation of multi-sensor\\/multi-source systems. Proposed modifications include broadening of the functional model and related taxonomy beyond the original military focus, and integrating the Data Fusion

A. N. Steinberg; C. L. Bowman; F. E. White

1999-01-01

266

Z-Pinch Fusion for Energy Applications  

SciTech Connect

Z pinches, the oldest fusion concept, have recently been revisited in light of significant advances in the fields of plasma physics and pulsed power engineering. The possibility exists for z-pinch fusion to play a role in commercial energy applications. We report on work to develop z-pinch fusion concepts, the result of an extensive literature search, and the output for a congressionally-mandated workshop on fusion energy held in Snowmass, Co July 11-23,1999.

SPIELMAN,RICK B.

2000-01-01

267

The automorphisms of affine fusion rings  

E-print Network

The fusion rings associated to affine Kac-Moody algebras appear in several different contexts in math and mathematical physics. In this paper we find all automorphisms of all affine fusion rings, or equivalently the symmetries of the corresponding fusion coefficients. Most of these are directly related to symmetries of the corresponding Coxeter-Dynkin diagram. We also find all pairs of isomorphic affine fusion rings.

T. Gannon

2000-02-07

268

A Review of Data Fusion Techniques  

PubMed Central

The integration of data and knowledge from several sources is known as data fusion. This paper summarizes the state of the data fusion field and describes the most relevant studies. We first enumerate and explain different classification schemes for data fusion. Then, the most common algorithms are reviewed. These methods and algorithms are presented using three different categories: (i) data association, (ii) state estimation, and (iii) decision fusion. PMID:24288502

2013-01-01

269

THE FUSION HYBRID, A NEW (OLD ) IDEA FOR FUSION DEVELOPMENT  

E-print Network

~ 1990 COMMERICAL POWER PLANT 50 YEARS IN THE FUTURE IF THE WHOLE WORLD BUILDS LARGE ITER (ADMIRAL A DIFFICULT CREDIBILITY PROBLEM: · T~1955 FUSION POWERED ROCKETS 30 YEARS IN THE FUTURE (LIFE MAGAZINE) · T WITH OR WITHOUT USA #12;·T ~ 2003: DOE NOW ASKS IF WE CAN GET A COMMERCIAL REACTOR ON LINE IN 35 YEARS, 3 YEARS

270

Fusion for Neutrons as a Necessary Step to Commercial Fusion  

E-print Network

, T 1 *1.8 1.4 1012 6. Z-pinch *Z (Albuquerque), D, T 30 70 24 1017 7. Laser system *LIFE (LLNL), D/s Compact tokamaks with copper coils and MW fusion power may compete with contemporary neutron sources systems in Russia came back because: Resources of U-235 for development of power generation by thermal

271

Magneto-Inertial Fusion (Magnetized Target Fusion)( g g )  

E-print Network

. In this Talk: ·Magnetized Target Fusion (MTF) demonstration, FRCHX at AFRL in Albuquerque ·Some MIF-IFE reactor/Target Combinations are possible Los Alamos / AFRL Field Reversed Configuration Shiva Star FRCHX U. Rochester LLE. White, H. Wood Air Force Research Laboratory, Directed Energy Directorate, Kirtland AFB, NM 87117, USA D

272

Systematic analysis of advanced fusion fuel in inertial fusion energy  

Microsoft Academic Search

Aneutronic fusion reactions can be considered as the cleanest way to exploit nuclear energy. However, these reactions present in general two main drawbacks.-very high temperatures are needed to reach relevant values of their cross sections-Moderate (and even low) energy yield per reaction. This value is still lower if measured in relation to the Z number of the reacting particles. It

G. Velarde; S. Eliezer; Z. Henis; M. Piera; J. M. Martinez-Val

1997-01-01

273

Fusion project decision delayed ITER -NUCLEAR FUSION PROJECT  

E-print Network

the International Space Station. Scientists say it will be the first fusion device to produce thermal energy-free energy - but the reactor will take 10 years to build. Pros and cons Member countries of the International also be the world's largest international co-operative research and development project after

274

Image Fusion: Principles, Methods, and Applications  

E-print Network

Image Fusion: Principles, Methods, and Applications Tutorial EUSIPCO 2007 Lecture Notes Jan Flusser,sroubekf,zitova}@utia.cas.cz #12;Introduction The term fusion means in general an approach to extraction of information acquired in several domains. The goal of image fusion (IF) is to integrate complementary multisensor, multitemporal

Sroubek, Filip

275

Exotic fusion systems over 2-groups  

E-print Network

Exotic fusion systems over 2-groups Bob Oliver joint with Kasper Andersen and Joana Ventura The fusion category of a finite group G encodes the conjugacy relations within a Sylow p-subgroup S of GFS(G)(P, Q) = HomG(P, Q). 1 #12;The notion of an abstract fusion system is due to Puig. The definitions we

Thévenaz, Jacques

276

FUSION POWER PLANTS GOALS AND TECHNOLOGICAL CHALLENGES  

E-print Network

FUSION POWER PLANTS ­ GOALS AND TECHNOLOGICAL CHALLENGES Farrokh Najmabadi Dept. of Electrical & Computer Eng. and Fusion Energy Research Program, University of California, San Diego, La Jolla, CA 92093-0417 619-534-7869 (619-534-7716, Fax) ABSTRACT Fusion is one of a few future power sources with the poten

Najmabadi, Farrokh

277

FUSION CATEGORIES AND MODULE CATEGORIES EVAN JENKINS  

E-print Network

FUSION CATEGORIES AND MODULE CATEGORIES EVAN JENKINS k is an algebraically closed field of bilinear functors C Ă? D E. 2. Fusion categories Definition. Let C be a tensor/monoidal category. C is called a fusion category if (1) Every object has a left and right dual (2) 1 is simple. Examples (G

Proudfoot, Nicholas

278

CONFERENCES AND SYMPOSIA FUSION REACTOR DESIGN IV  

E-print Network

CONFERENCES AND SYMPOSIA FUSION REACTOR DESIGN IV Report on the Fourth IAEA Technical Committee; 7.3. Recommendations; 8. Hybrid Fusion-Fission Reactors; 8.1. Status; 8.2. Progress of fusion power reactor development is to bring to the world a new source of unlimited energy. While

Abdou, Mohamed

279

COMMENTARIES ON CRITICISMS OF MAGNETIC FUSION  

E-print Network

Engineering Heat Transfer Limits for D-T Fusion Reactors. p16 Technical Annex 2 Advanced Tokamak Modes--there is no CO2 produced, and decommissioned fusion reactor materials should qualify as low fusion reactors are within less than a factor of two of costs projected for other energy sources, without

280

Heavy Ion Fusion Science Virtual National Laboratory  

E-print Network

Slide 1 Heavy Ion Fusion Science Virtual National Laboratory Briefing for the National Academy review of Inertial Fusion Energy B. Grant Logan Director, U.S. Heavy Ion Fusion Science Virtual National Laboratory, a collaboration of LBNL, LLNL, and PPPL heavy ion research *This work was performed under

281

A wavelet-based image fusion tutorial  

Microsoft Academic Search

The objective of image fusion is to combine information from multiple images of the same scene. The result of image fusion is a new image which is more suitable for human and machine perception or further image-processing tasks such as segmentation, feature extraction and object recognition. Di4erent fusion methods have been proposed in literature, including multiresolution analysis. This paper is

Gonzalo Pajares; Jesús Manuel De La Cruz

2004-01-01

282

LIFE Power Plant Fusion Power Associates  

E-print Network

LIFE Power Plant Fusion Power Associates December 14, 2011 Mike Dunne LLNL #12;NIf-1111-23714.ppt LIFE power plant 2 #12;LIFE delivery timescale NIf-1111-23714.ppt 3 #12;Timely delivery is enabled fusion options exist. NIF/LIFE allows timely integrated demonstration. · Fusion performance based

283

Multibiometric Cryptosystems based on Feature Level Fusion  

E-print Network

1 Multibiometric Cryptosystems based on Feature Level Fusion Abhishek Nagar, Student Member, IEEE sketches. In this paper, we propose a feature level fusion framework to simultaneously protect multiple of the proposed feature level fusion framework using two well- known biometric cryptosystems, namely, fuzzy vault

284

Remote computing using the National Fusion Grid  

Microsoft Academic Search

The National Fusion Collaboratory (http:\\/\\/www.fusiongrid.org) uses grid technology to implement remote computing on the National Fusion Grid. The motivations are to reduce the cost of computing resources, shorten the software deployment cycle, and simplify remote computing for the user community. The National Fusion Collaboratory has successfully demonstrated remote access as a grid service to the TRANSP transport analysis code for

J. R. Burruss; S Flanagan; K Keahey; C Ludescher; D. C McCune; Q Peng; L Randerson; D. P Schissel; M Thompson

2004-01-01

285

Compact Fusion Advanced Rankine (CFARII) power cycle  

Microsoft Academic Search

The Compact Fusion Advanced Rankine (CFARII) power cycle is a direct plasma energy conversion scheme for inertial fusion (ICF) and magnetically-insulated, inertially confined fusion (MICF) reactors utilizing: (1) conversion of plasma thermal ionization and thermal energy into kinetic energy of a supersonic plasma jet, (2) conversion of the plasma jet kinetic energy into DC electricity by slowing down in an

Logan

1991-01-01

286

Novel fusion energy conversion methods  

Microsoft Academic Search

The potential importance of direct energy conversion to the long-term development of fusion power is discussed with emphasis on the possibility of alleviating waste heat problems. This is envisioned to be important for any central power station in the 21st century and crucial for future space applications. Various novel conversion methods are briefly considered, including direct collection, magnetic expansion, synchroton

L. J. Perkins; G. H. Miley; B. G. Logan

1988-01-01

287

Sensor Fusion for Augmented Reality  

Microsoft Academic Search

The problem of estimating the position and orientation (pose) of a camera is approached by fusing measurements from inertial sensors (accelerometers and rate gyroscopes) and a camera. The sensor fusion approach described in this contribution is based on nonlinear filtering using the measurements from these complementary sensors. This way, accurate and robust pose estimates are available for the primary purpose

Fredrik Gustafsson; Thomas B. Schon; Jeroen D. Hol

2007-01-01

288

Proton Collimators for Fusion Reactors  

NASA Technical Reports Server (NTRS)

Proton collimators have been proposed for incorporation into inertial-electrostatic-confinement (IEC) fusion reactors. Such reactors have been envisioned as thrusters and sources of electric power for spacecraft and as sources of energetic protons in commercial ion-beam applications.

Miley, George H.; Momota, Hiromu

2003-01-01

289

Power Exhaust in Fusion Plasmas  

NASA Astrophysics Data System (ADS)

Preface; 1. Introduction; 2. Magnetized plasma physics; 3. Magnetized plasma equilibrium; 4. Magnetized plasma stability; 5. Collisional transport in magnetized plasmas; 6. Turbulent transport in magnetized plasmas; 7. Tokamak plasma boundary and power exhaust; 8. Outlook: power exhaust in fusion reactors; Appendix A. Maxwellian distribution; Appendix B. Curvilinear co-ordinates; References; Index.

Fundamenski, Wojciech

2014-07-01

290

data fusion 15 June 2012  

E-print Network

interesting movies of particle flow and many numerical results. The key idea is to compute Bayes' rule using ruin multi-sensor fusion 300 total targets: 30 missiles, 10 targets per missile Position error = 100m, Separation of targets in missile complex = 500m, 1500m 60 70 80 90 100 %Correctassignments GNPL 0 10 20 30 40

Dobigeon, Nicolas

291

Fusion for Earth and Space  

Microsoft Academic Search

The compact reactor concept (Williams, 2007) has the potential to provide clean, safe and unlimited supply of energy for Earth and Space applications. The concept is a potential fusion reactor wherein deuterium nuclei are preferentially fused into helium nuclei. Because the deuterium nuclei are preferentially fused into helium nuclei at temperatures and energies lower than specified by the standard model

Pharis E. Williams; Pharis E

2009-01-01

292

Advanced algorithms for distributed fusion  

NASA Astrophysics Data System (ADS)

The US Military has been undergoing a radical transition from a traditional "platform-centric" force to one capable of performing in a "Network-Centric" environment. This transformation will place all of the data needed to efficiently meet tactical and strategic goals at the warfighter's fingertips. With access to this information, the challenge of fusing data from across the batttlespace into an operational picture for real-time Situational Awareness emerges. In such an environment, centralized fusion approaches will have limited application due to the constraints of real-time communications networks and computational resources. To overcome these limitations, we are developing a formalized architecture for fusion and track adjudication that allows the distribution of fusion processes over a dynamically created and managed information network. This network will support the incorporation and utilization of low level tracking information within the Army Distributed Common Ground System (DCGS-A) or Future Combat System (FCS). The framework is based on Bowman's Dual Node Network (DNN) architecture that utilizes a distributed network of interlaced fusion and track adjudication nodes to build and maintain a globally consistent picture across all assets.

Gelfand, A.; Smith, C.; Colony, M.; Bowman, C.; Pei, R.; Huynh, T.; Brown, C.

2008-03-01

293

EURATOM/CCFE Fusion Association  

E-print Network

from the MAST Beam Emission Spectroscopy system ­ a diagnostic built by the Hungarian fusion productive year for CCFE. I have only picked out two highlights, but you will find many more examples of excellence throughout this year's report. Images of plasma turbulence produced by MAST's new Beam Emission

294

Prospects of inertial confinement fusion  

Microsoft Academic Search

The present status of inertial confinement fusion (ICF) is briefly reviewed, emphasizing the National Ignition Facility (NIF) project in the US and the Megajoule project in France. Critical aspects of target performance such as symmetry and stability of capsule implosions and interaction physics in hohlraum targets are discussed. The advantages of heavy-ion beam drivers and corresponding research programs are pointed

J. Meyer-ter-Vehn

1997-01-01

295

Magnetic Fusion Pilot Plant Studies  

E-print Network

Street, Washington, DC December 1-2, 2010 #12;Exploring "Pilot Plant" as a possible pathway from ITER to commercial fusion power plant ITER First of a kind Power Plant (= U.S. Demo) Supporting Physics of the pilot plant study 1. Understand the characteristics of pilot plant ­ Role as step to commercial magnetic

296

Fusion Power Associates Annual Meeting  

E-print Network

Fusion Power Associates Annual Meeting Washington, DC 2 December 2009 R. L. McCrory Professor OMEGA (2009) OMEGA hydro-equivalent ignition Q = 2 Ignition CTF FRC Spheromak RFP ST Stellarator Tokamak to Physical Review Letters. 0 1 0 2 3 2 4 6 8 Time (ns) Three-picket NIF design Power/beam(TW) 10 12 160 nm DT

297

Inertial confinement fusion (ICF) review  

SciTech Connect

During its 1996 winter study JASON reviewed the DOE Inertial Confinement Fusion (ICF) program. This included the National Ignition Facility (NIF) and proposed studies. The result of the review was to comment on the role of the ICF program in support of the DOE Science Based Stockpile Stewardship program.

Hammer, D.; Dyson, F.; Fortson, N.; Novick, B.; Panofsky, W.; Rosenbluth, M.; Treiman, S.; York, H.

1996-03-01

298

Fusion Nuclear Science Facility (FNSF)  

E-print Network

.); International Workshop on MFE Road- mapping in the ITER Era September 7-10, 2011 Princeton, New Jersey, USA #12 Extraction 1. Fusion Plasma Dynamics and Control: ITER: Construction First Plasma 500MW DT Burn U Samples Nuclear Effects: HFIR Capsule: 70 dpa Component:150 dpa FNSF: Mission Design Construction

299

CELL BIOLOGY: Fusion Without SNAREs?  

NSDL National Science Digital Library

Access to the article is free, however registration and sign-in are required. Highly orchestrated molecular rearrangements are required for two membranes to fuse, as happens, for example, during neurotransmitter release into the synapse. In an elegant Perspective, Scales et al. discuss two studies (Schoch et al., Wang et al.) that shed new light on the protein interactions involved in membrane fusion.

Suzie J. Scales (Genentech Inc.;); Michael F. A. Finley (Stanford University Medical School;Department of Molecular and Cellular Physiology); Richard H. Scheller (Genentech Inc.;)

2001-11-02

300

Cognitive high level information fusion  

Microsoft Academic Search

Fusion of sensor and communication data currently can only be performed at a late processing stage after sensor and textual information are formulated as logical statements at appropriately high level of abstraction. Contrary to this it seems, the human mind integrates sensor and language signals seamlessly, before signals are understood, at pre-conceptual level. Learning of conceptual contents of the surrounding

Leonid I. Perlovsky

2007-01-01

301

Distribution Category: Magnetic Fusion Energy  

E-print Network

Potential 30 5. Sensitivity to Data Uncertainties 32 6. Recommended Effort 40 7. Nuclear Data Needs 44 Effect of fractional burnup and doubling time upon required breeding ratio 12 5 Vertical cross section in Fusion Power Reactors 31 XI Description of Two Blanket Concepts for Sensitivity (Analysis performed

Abdou, Mohamed

302

Magnetized Target Fusion: Prospects for Low-Cost Fusion Energy  

NASA Technical Reports Server (NTRS)

Magnetized Target Fusion (MTF) has attracted renewed interest in recent years because it has the potential to resolve one of the major problems with conventional fusion energy research - the high cost of facilities to do experiments and in general develop practical fusion energy. The requirement for costly facilities can be traced to fundamental constraints. The Lawson condition implies large system size in the case of conventional magnetic confinement, or large heating power in the case of conventional inertial confinement. The MTF approach is to use much higher fuel density than with conventional magnetic confinement (corresponding to megabar pressures), which results in a much-reduced system size to achieve Lawson conditions. Intrinsically the system must be pulsed because the pressures exceed the strength of any known material. To facilitate heating the fuel (or "target") to thermonuclear conditions with a high-power high-intensity source of energy, magnetic fields are used to insulate the high-pressure fuel from material surroundings (thus "magnetized target"). Because of magnetic insulation, the required heating power intensity is reduced by many orders of magnitude compared to conventional inertial fusion, even with relatively poor energy confinement in the magnetic field, such as that characterized by Bohm diffusion. In this paper we show semi-quantitatively why MTF-should allow fusion energy production without costly facilities within the same generally accepted physical constraints used for conventional magnetic and inertial fusion. We also briefly discuss potential applications of this technology ranging from nuclear rockets for space propulsion to a practical commercial energy system. Finally, we report on the exploratory research underway, and the interesting physics issues that arise in the MTF regime of parameters. Experiments at Los Alamos are focused on formation of a suitable plasma target for compression, utilizing the knowledge base for compact toroids called Field-Reversed Configurations. As reported earlier, it appears that the existing pulsed-power Shiva Star facility at the Air Force Research Laboratory in Albuquerque, NM can satisfy the heating requirements by means of imploding a thin metal cylinder (called a "liner") surrounding an FRC of the type presently being developed. The proposed next step is an integrated liner-on-plasma experiment in which an FRC would be heated to 10 keV by the imploding liner.

Siemon, Richard E.; Turchi, Peter J.; Barnes, Daniel C.; Degnan, James; Parks, Paul; Ryutov, Dmitri D.; Thio, Y. C. Francis; Schafer, Charles (Technical Monitor)

2001-01-01

303

Measuring time of flight of fusion products in an inertial electrostatic confinement fusion device for spatial profiling of fusion reactions  

SciTech Connect

A new diagnostic has been developed that uses the time of flight (TOF) of the products from a nuclear fusion reaction to determine the location where the fusion reaction occurred. The TOF diagnostic uses charged particle detectors on opposing sides of the inertial electrostatic confinement (IEC) device that are coupled to high resolution timing electronics to measure the spatial profile of fusion reactions occurring between the two charged particle detectors. This diagnostic was constructed and tested by the University of Wisconsin-Madison Inertial Electrostatic Confinement Fusion Group in the IEC device, HOMER, which accelerates deuterium ions to fusion relevant energies in a high voltage ({approx}100 kV), spherically symmetric, electrostatic potential well [J. F. Santarius, G. L. Kulcinski, R. P. Ashley, D. R. Boris, B. B. Cipiti, S. K. Murali, G. R. Piefer, R. F. Radel, T. E. Radel, and A. L. Wehmeyer, Fusion Sci. Technol. 47, 1238 (2005)]. The TOF diagnostic detects the products of D(d,p)T reactions and determines where along a chord through the device the fusion event occurred. The diagnostic is also capable of using charged particle spectroscopy to determine the Doppler shift imparted to the fusion products by the center of mass energy of the fusion reactants. The TOF diagnostic is thus able to collect spatial profiles of the fusion reaction density along a chord through the device, coupled with the center of mass energy of the reactions occurring at each location. This provides levels of diagnostic detail never before achieved on an IEC device.

Donovan, D. C. [Sandia National Laboratories, 7011 East Avenue, Livermore, California 94550 (United States); Boris, D. R. [Naval Research Laboratory, 4555 Overlook Avenue, South West, Washington, DC 20375 (United States); Kulcinski, G. L.; Santarius, J. F. [Fusion Technology Institute, University of Wisconsin-Madison, 1500 Engineering Drive, Madison, Wisconsin 53706 (United States); Piefer, G. R. [Phoenix Nuclear Labs, 2555 Industrial Drive, Madison, Wisconsin 53713 (United States)

2013-03-15

304

ProFusion*: Intelligent Fusion from Multiple, Distributed Search Engines  

Microsoft Academic Search

The explosive growth of the World Wide Web, and the resulting information overload, has led to a mini-explosion in World Wide Web search engines. This mini-explosion, in turn, led to the development of ProFusion, a meta search engine. Educators, like other users, do not have the time to evaluate multiple search engines to knowledgeably select the best for their uses.

Susan Gauch; Guijun Wang; Mario Gomez

1996-01-01

305

The fusion hybrid, a new (old) development plan for fusion  

NASA Astrophysics Data System (ADS)

For world development to proceed, mid-century energy requirements are daunting. Estimates are that by 2050, the world will need 10-30 terawatts (TW) of additional energy (we generate about 13 TW today, mostly with fossil fuel). However to avoid possibly disastrous climate change, this additional energy should be carbon-free [1]. Another study looks at how this might be accomplished [2]. The startling conclusion from Ref. [2] is that options are few, and any option would require greater changes to the world's energy systems than have occurred in the last fifty years. This paper proposes that fusion can be a player in the quest to power the mid-century world, but only by contributing to the fission/fusion hybrid. My own very preliminary study indicates that a fusion hybrid could deliver energy to the world in a timely manner, and in an economically and environmentally acceptable way. [1] M. Hoffert et. al., Nature, 395, 881, (1998) [2] M. Hoffert et al, Science, 298, 981, (2002)

Manheimer, Wallace

2006-10-01

306

Fusion technologies for Laser Inertial Fusion Energy (LIFE)  

NASA Astrophysics Data System (ADS)

The Laser Inertial Fusion-based Energy (LIFE) engine design builds upon on going progress at the National Ignition Facility (NIF) and offers a near-term pathway to commercial fusion. Fusion technologies that are critical to success are reflected in the design of the first wall, blanket and tritium separation subsystems. The present work describes the LIFE engine-related components and technologies. LIFE utilizes a thermally robust indirect-drive target and a chamber fill gas. Coolant selection and a large chamber solid-angle coverage provide ample tritium breeding margin and high blanket gain. Target material selection eliminates the need for aggressive chamber clearing, while enabling recycling. Demonstrated tritium separation and storage technologies limit the site tritium inventory to attractive levels. These key technologies, along with the maintenance and advanced materials qualification program have been integrated into the LIFE delivery plan. This describes the development of components and subsystems, through prototyping and integration into a First Of A Kind power plant. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

Kramer, K. J.; Latkowski, J. F.; Abbott, R. P.; Anklam, T. P.; Dunne, A. M.; El-Dasher, B. S.; Flowers, D. L.; Fluss, M. J.; Lafuente, A.; Loosmore, G. A.; Morris, K. R.; Moses, E.; Reyes, S.

2013-11-01

307

Multiscale Medical Image Fusion in Wavelet Domain  

PubMed Central

Wavelet transforms have emerged as a powerful tool in image fusion. However, the study and analysis of medical image fusion is still a challenging area of research. Therefore, in this paper, we propose a multiscale fusion of multimodal medical images in wavelet domain. Fusion of medical images has been performed at multiple scales varying from minimum to maximum level using maximum selection rule which provides more flexibility and choice to select the relevant fused images. The experimental analysis of the proposed method has been performed with several sets of medical images. Fusion results have been evaluated subjectively and objectively with existing state-of-the-art fusion methods which include several pyramid- and wavelet-transform-based fusion methods and principal component analysis (PCA) fusion method. The comparative analysis of the fusion results has been performed with edge strength (Q), mutual information (MI), entropy (E), standard deviation (SD), blind structural similarity index metric (BSSIM), spatial frequency (SF), and average gradient (AG) metrics. The combined subjective and objective evaluations of the proposed fusion method at multiple scales showed the effectiveness and goodness of the proposed approach. PMID:24453868

Khare, Ashish

2013-01-01

308

Investigation of condensed matter fusion  

SciTech Connect

Work on muon-catalyzed fusion led to research on a possible new type of fusion occurring in hydrogen isotopes embedded in metal lattices. While the nuclear-product yields observed to date are so small as to require careful further checking, rates observed over short times appear sufficiently large to suggest that significant neutrons and triton yields could be realized -- if the process could be understood and controlled. During 1990, we have developed two charged-particle detection systems and three new neutron detectors. A segmented, high-efficiency neutron counter was taken into 600 m underground in a mine in Colorado for studies out of the cosmic-ray background. Significant neutron emissions were observed in this environment in both deuterium-gas-loaded metals and in electrolytic cells, confirming our earlier observations.

Jones, S.E.; Berrondo, M.; Czirr, J.B.; Decker, D.L.; Harrison, K.; Jensen, G.L.; Palmer, E.P.; Rees, L.B.; Taylor, S.; Vanfleet, H.B.; Wang, J.C.; Bennion, D.N.; Harb, J.N.; Pitt, W.G.; Thorne, J.M.; Anderson, A.N.; McMurtry, G.; Murphy, N.; Goff, F.E.

1990-12-01

309

Prospects for toroidal fusion reactors  

NASA Astrophysics Data System (ADS)

Work on the International Thermonuclear Experimental Reactor (ITER) tokamak has refined understanding of the realities of a deuterium-tritium (D-T) burning magnetic fusion reactor. An ITER-like tokamak reactor using ITER costs and performance would lead to a cost of electricity (COE) of about 130 mills/kWh. Advanced tokamak physics to be tested in the Toroidal Physics Experiment (TPX), coupled with moderate components in engineering, technology, and unit costs, should lead to a COE comparable with best existing fission systems around 60 mills/kWh. However, a larger unit size, approximately 2000 MW(e), is favored for the fusion system. Alternative toroidal configurations to the conventional tokamak, such as the stellarator, reversed-field pinch, and field-reversed configuration, offer some potential advantage, but are less well developed, and have their own challenges.

Sheffield, J.; Galambos, J. D.

1994-06-01

310

Trust metrics in information fusion  

NASA Astrophysics Data System (ADS)

Trust is an important concept for machine intelligence and is not consistent across many applications. In this paper, we seek to understand trust from a variety of factors: humans, sensors, communications, intelligence processing algorithms and human-machine displays of information. In modeling the various aspects of trust, we provide an example from machine intelligence that supports the various attributes of measuring trust such as sensor accuracy, communication timeliness, machine processing confidence, and display throughput to convey the various attributes that support user acceptance of machine intelligence results. The example used is fusing video and text whereby an analyst needs trust information in the identified imagery track. We use the proportional conflict redistribution rule as an information fusion technique that handles conflicting data from trusted and mistrusted sources. The discussion of the many forms of trust explored in the paper seeks to provide a systems-level design perspective for information fusion trust quantification.

Blasch, Erik

2014-05-01

311

Mechanisms Regulating Human Trophoblast Fusion  

Microsoft Academic Search

\\u000a In the human placenta, the syncytiotrophoblast is part of the villous trophoblast, which is the epithelial cover of the placental\\u000a villi floating in maternal blood. The villous trophoblast is composed of two layers, the syncytiotrophoblast in direct contact\\u000a to maternal blood and the underlying layer of mononucleated cytotrophoblasts. Throughout pregnancy there is continuous fusion\\u000a of cytotrophoblast with the syncytiotrophoblast to

Berthold Huppertz; Martin Gauster

312

Heavy Ion Fusion Injector Program  

SciTech Connect

A program is underway to construct a 2 MV, 800 mA, K{sup +} injector for heavy ion fusion. The Electrostatic Quadrupole (ESQ) injector configuration consists of a zeolite source, a diode of up to 1 MV, together with several electrostatic quadrupole units to simultaneously focus and accelerate the beam to 2 MV. The key issues of source technology, high voltage breakdown, beam aberrations, and transient effects will be discussed. Results from ongoing experiments and simulations will be presented.

Yu, S.; Eylon, S.; Chupp, W.W.

1993-05-01

313

Inertial fusion activities in Spain  

Microsoft Academic Search

A method is proposed to exploit the aneutronic p-11B fusion reaction by means of igniting a heat detonation wave that expands across the fuel from a small heated region. The tritium seeding effect of DT, 6LiD, 7LiD, p11B, 10BD, 3HeD fuels has been analysed, showing that the impact of initial tritium is not so important in aneutronic reactions. The 2D

G Velarde; J M. Perlado; E Alonso; M. D Cobo; A Crisol; L Doreste; J. M Gil; L González; J Honrubia; L. F Ibáńez; P Martel; E Minguez; J. M Mart??nez-Val; F Ogando; M Piera; R Piriz; J Ram??rez; R Ramis; J. G Rubiano; M Sanchez; J Sanz; G. J Sanz; P Velarde

1998-01-01

314

ACE Mission - Fusion and Nucleosynthesis  

NSDL National Science Digital Library

This educational brief explains the idea that nuclear fusion is thought to be the mechanism by which virtually all of the elements around us are created. Topics include the proton-proton cycle, the carbon-nitrogen-oxygen cycle, and endothermic reactions in supernova explosions. There is also a discussion of the Advanced Composition Explorer (ACE), a spacecraft intended to study the origin and evolution of the elements produced by our Sun.

315

ACE Mission - Fusion and Nucleosynthesis  

NSDL National Science Digital Library

This educational brief explains the idea that nuclear fusion is thought to be the mechanism by which virtually all of the elements around us are created. Topics include the proton-proton cycle, the carbon-nitrogen-oxygen cycle, and endothermic reactions in supernova explosions. There is also a discussion of the Advanced Composition Explorer (ACE), a spacecraft intended to study the origin and evolution of the elements produced by our Sun.

2011-06-30

316

Nuclear Fusion in Dense Matter  

SciTech Connect

The standard theory of nuclear fusion rates in strongly interacting plasmas can be (correctly) derived only when the energy release Q is large compared to other energies in the problem. We exhibit a result for rates that provides a basis for calculating the finite Q corrections. Crude estimates indicate a significant defect in the conventional results for some regions of high density and strong plasma coupling. We also lay some groundwork for a path integral calculation of the new effects.

Sawyer, R. F. [Department of Physics, University of California at Santa Barbara, Santa Barbara, California 93106 (United States)

2010-05-14

317

Gasdynamic Mirror Fusion Propulsion Experiment  

NASA Technical Reports Server (NTRS)

Nuclear fusion appears to be the most promising concept for producing extremely high specific impulse rocket engines. One particular fusion concept which seems to be particularly well suited for fusion propulsion applications is the gasdynamic mirror (GDM). This device would operate at much higher plasma densities and with much larger LD ratios than previous mirror machines. Several advantages accrue from such a design. First, the high LA:) ratio minimizes to a large extent certain magnetic curvature effects which lead to plasma instabilities causing a loss of plasma confinement. Second, the high plasma density will result in the plasma behaving much more Re a conventional fluid with a mean free path shorter than the length of the device. This characteristic helps reduce problems associated with "loss cone" microinstabilities. An experimental GDM device is currently being constructed at the NASA Marshall Space Flight Center to provide an initial assessment of the feasibility of this type of propulsion system. Initial experiments are expected to commence in the late fall of 2000.

Emrich, William J., Jr.; Rodgers, Stephen L. (Technical Monitor)

2001-01-01

318

Posterior Instrumentation for Occipitocervical Fusion  

PubMed Central

Since 1995, 29 consecutive patients with craniocervical spine instability due to several pathologies were managed with posterior occipitocervical instrumentation and fusion. Laminectomy was additionally performed in nineteen patients. The patients were divided in two groups: Group A which included patients managed with screw-rod instrumentation, and Group B which included patients managed with hook-and-screw-rod instrumentation. The patients were evaluated clinically and radiographically using the following parameters: spine anatomy and reconstruction, sagittal profile, neurologic status, functional level, pain relief, complications and status of arthrodesis. The follow-up was performed immediately postoperatively and at 2, 6, 12 months after surgery, and thereafter once a year. Fusion was achieved in all but one patient. One case of infection was the only surgery related complication. Neurological improvement and considerable pain relief occurred in the majority of patients postoperatively. There were neither intraoperative complications nor surgery related deaths. However, the overall death rate was 37.5% in group A, and 7.7% in group B. There were no instrument related failures. The reduction level was acceptable and was maintained until the latest follow-up in all of the patients. No statistical difference between the outcomes of screw-rod and hook-and-screw-rod instrumentation was detected. Laminectomy did not influence the outcome in either group. Screw-rod and hook-and-screw-rod occipitocervical fusion instrumentations are both considered as safe and effective methods of treatment of craniocervical instability. PMID:21772931

Sapkas, George; Papadakis, Stamatios A; Segkos, Dimitrios; Kateros, Konstantinos; Tsakotos, George; Katonis, Pavlos

2011-01-01

319

Fusion for Earth and Space  

NASA Astrophysics Data System (ADS)

The compact reactor concept (Williams, 2007) has the potential to provide clean, safe and unlimited supply of energy for Earth and Space applications. The concept is a potential fusion reactor wherein deuterium nuclei are preferentially fused into helium nuclei. Because the deuterium nuclei are preferentially fused into helium nuclei at temperatures and energies lower than specified by the standard model there is no harmful radiation as a byproduct of this fusion process. Therefore, a reactor using this reaction does not need any shielding to contain such radiation. The energy released from each reaction and the absence of shielding makes the deuterium-plus-deuterium-to-helium (DDH) reactor very compact when compared to other reactors, both fission and fusion types. Moreover, the potential energy output per reactor weight and the absence of harmful radiation makes the DDH reactor an ideal candidate for individual home and space power. The concept also would make it possible for each plant or remote location to have it's own power source, on site, without the need for a connection to the power grid. This would minimize, or eliminate, power blackouts. The concept could replace large fission reactors and fossil fuel power plants plus provide energy for ships, locomotives, trucks and autos. It would make an ideal source of energy for space power applications and for space propulsion.

Williams, Pharis E.

2009-03-01

320

Inertial fusion experiments and theory  

NASA Astrophysics Data System (ADS)

Inertial fusion research is approaching a critical milestone, namely the demonstration of ignition and burn. The world's largest high-power laser, the National Ignition Facility (NIF), is under operation at the Lawrence Livermore National Laboratory (LLNL), in the USA. Another ignition machine, Laser Mega Joule (LMJ), is under construction at the CEA/CESTA research centre in France. In relation to the National Ignition Campaign (NIC) at LLNL, worldwide studies on inertial fusion applications to energy production are growing. Advanced ignition schemes such as fast ignition, shock ignition and impact ignition, and the inertial fusion energy (IFE) technology are under development. In particular, the Fast Ignition Realization Experiment (FIREX) at the Institute of Laser Engineering (ILE), Osaka University, and the OMEGA-EP project at the Laboratory for Laser Energetics (LLE), University Rochester, and the HiPER project in the European Union (EU) for fast ignition and shock ignition are progressing. The IFE technology research and development are advanced in the frameworks of the HiPER project in EU and the LIFE project in the USA. Laser technology developments in the USA, EU, Japan and Korea were major highlights in the IAEA FEC 2010. In this paper, the status and prospects of IFE science and technology are described.

Mima, Kunioki; Tikhonchuk, V.; Perlado, M.

2011-09-01

321

FUSION SYSTEMS FOR PROFINITE GROUPS RADU STANCU AND PETER SYMONDS  

E-print Network

FUSION SYSTEMS FOR PROFINITE GROUPS RADU STANCU AND PETER SYMONDS Abstract. We introduce the notion of a pro-fusion system on a pro-p group, which generalizes the notion of a fusion system on a finite p-group. We also prove a version of Alperin's Fusion Theorem for pro-fusion systems. 1. Introduction Profinite

Symonds, Peter

322

Fusion Frames Peter G. Casazza and Gitta Kutyniok  

E-print Network

Chapter 1 Fusion Frames Peter G. Casazza and Gitta Kutyniok Abstract Novel technological advances. Fusion frames, which can be regarded as frames of subspaces, do satisfy exactly those needs. They analyze, distributed processing, fusion coherence, fusion frame, fusion frame potential, isoclinic subspaces, mutually

Kutyniok, Gitta

323

The Diversified International Portfolio for Fusion Based on FIRE  

E-print Network

Plasma Physics and Fusion Energy Development," Journal of Fusion Energy, V19, Ch 3, Number 1, 2000 6 3(8), (1991). 3. "The U.S. Program of Fusion Energy Research and Development," Presidents Fusion Program," Journal of Fusion Energy 2000 5. C. Baker et al, "Possible Pathways for Pursuing Burning

324

Spectrally Consistent Satellite Image Fusion with Improved Image Priors  

E-print Network

]. Image fusion can be done at several levels: Pixel level, feature level, object level and decision level, depending on the intended use of the fused image. This paper is only concerned with pixel level fusion and when the terms "image fusion" or "fusion" are used, pixel level fusion is intended. In the current

325

Robust Late Fusion With Rank Minimization Guangnan Ye  

E-print Network

. Early fusion, also known as feature level fusion, has been widely used in the computer vision classification tasks [2, 5, 10]. There are two popular strategies to fuse features: early fusion and late fusion in the kernel space. One of the most successful feature fusion methods is Multiple Kernel Learning (MKL) [2

Chang, Shih-Fu

326

History of Nuclear Fusion Research in Japan  

NASA Astrophysics Data System (ADS)

In the late 1950s just after the atomic energy research was opened worldwide, there was a lively discussion among scientists on the strategy of nuclear fusion research in Japan. Finally, decision was made that fusion research should be started from the basic, namely, research on plasma physics and from cultivation of human resources at universities under the Ministry of Education, Science and Culture (MOE). However, an endorsement was given that construction of an experimental device for fusion research would be approved sooner or later. Studies on toroidal plasma confinement started at Japan Atomic Energy Research Institute (JAERI) under the Science and Technology Agency (STA) in the mid-1960s. Dualistic fusion research framework in Japan was established. This structure has lasted until now. Fusion research activities over the last 50 years are described by the use of a flowchart, which is convenient to glance the historical development of fusion research in Japan.

Iguchi, Harukazu; Matsuoka, Keisuke; Kimura, Kazue; Namba, Chusei; Matsuda, Shinzaburo

327

Signaling mechanisms in mammalian myoblast fusion.  

PubMed

Myoblast fusion is a critical process that contributes to the growth of muscle during development and to the regeneration of myofibers upon injury. Myoblasts fuse with each other as well as with multinucleated myotubes to enlarge the myofiber. Initial studies demonstrated that myoblast fusion requires extracellular calcium and changes in cell membrane topography and cytoskeletal organization. More recent studies have identified several cell-surface and intracellular proteins that mediate myoblast fusion. Furthermore, emerging evidence suggests that myoblast fusion is also regulated by the activation of specific cell-signaling pathways that lead to the expression of genes whose products are essential for the fusion process and for modulating the activity of molecules that are involved in cytoskeletal rearrangement. Here, we review the roles of the major signaling pathways in mammalian myoblast fusion. PMID:23612709

Hindi, Sajedah M; Tajrishi, Marjan M; Kumar, Ashok

2013-04-23

328

Lunar Helium-3 and Fusion Power  

NASA Technical Reports Server (NTRS)

The NASA Office of Exploration sponsored the NASA Lunar Helium-3 and Fusion Power Workshop. The meeting was held to understand the potential of using He-3 from the moon for terrestrial fusion power production. It provided an overview, two parallel working sessions, a review of sessions, and discussions. The lunar mining session concluded that mining, beneficiation, separation, and return of He-3 from the moon would be possible but that a large scale operation and improved technology is required. The fusion power session concluded that: (1) that He-3 offers significant, possibly compelling, advantages over fusion of tritium, principally increased reactor life, reduced radioactive wastes, and high efficiency conversion, (2) that detailed assessment of the potential of the D/He-3 fuel cycle requires more information, and (3) D/He-3 fusion may be best for commercial purposes, although D/T fusion is more near term.

1988-01-01

329

EDITORIAL: Safety aspects of fusion power plants  

NASA Astrophysics Data System (ADS)

This special issue of Nuclear Fusion contains 13 informative papers that were initially presented at the 8th IAEA Technical Meeting on Fusion Power Plant Safety held in Vienna, Austria, 10-13 July 2006. Following recommendation from the International Fusion Research Council, the IAEA organizes Technical Meetings on Fusion Safety with the aim to bring together experts to discuss the ongoing work, share new ideas and outline general guidance and recommendations on different issues related to safety and environmental (S&E) aspects of fusion research and power facilities. Previous meetings in this series were held in Vienna, Austria (1980), Ispra, Italy (1983), Culham, UK (1986), Jackson Hole, USA (1989), Toronto, Canada (1993), Naka, Japan (1996) and Cannes, France (2000). The recognized progress in fusion research and technology over the last quarter of a century has boosted the awareness of the potential of fusion to be a practically inexhaustible and clean source of energy. The decision to construct the International Thermonuclear Experimental Reactor (ITER) represents a landmark in the path to fusion power engineering. Ongoing activities to license ITER in France look for an adequate balance between technological and scientific deliverables and complying with safety requirements. Actually, this is the first instance of licensing a representative fusion machine, and it will very likely shape the way in which a more common basis for establishing safety standards and policies for licensing future fusion power plants will be developed. Now that ITER licensing activities are underway, it is becoming clear that the international fusion community should strengthen its efforts in the area of designing the next generations of fusion power plants—demonstrational and commercial. Therefore, the 8th IAEA Technical Meeting on Fusion Safety focused on the safety aspects of power facilities. Some ITER-related safety issues were reported and discussed owing to their potential importance for the fusion power plant research programmes. The objective of this Technical Meeting was to examine in an integrated way all the safety aspects anticipated to be relevant to the first fusion power plant prototype expected to become operational by the middle of the century, leading to the first generation of economically viable fusion power plants with attractive S&E features. After screening by guest editors and consideration by referees, 13 (out of 28) papers were accepted for publication. They are devoted to the following safety topics: power plant safety; fusion specific operational safety approaches; test blanket modules; accident analysis; tritium safety and inventories; decommissioning and waste. The paper `Main safety issues at the transition from ITER to fusion power plants' by W. Gulden et al (EU) highlights the differences between ITER and future fusion power plants with magnetic confinement (off-site dose acceptance criteria, consequences of accidents inside and outside the design basis, occupational radiation exposure, and waste management, including recycling and/or final disposal in repositories) on the basis of the most recent European fusion power plant conceptual study. Ongoing S&E studies within the US inertial fusion energy (IFE) community are focusing on two design concepts. These are the high average power laser (HAPL) programme for development of a dry-wall, laser-driven IFE power plant, and the Z-pinch IFE programme for the production of an economically-attractive power plant using high-yield Z-pinch-driven targets. The main safety issues related to these programmes are reviewed in the paper `Status of IFE safety and environmental activities in the US' by S. Reyes et al (USA). The authors propose future directions of research in the IFE S&E area. In the paper `Recent accomplishments and future directions in the US Fusion Safety & Environmental Program' D. Petti et al (USA) state that the US fusion programme has long recognized that the S&E potential of fusion can be attained by prudent materials selecti

Kolbasov, B. N.

2007-07-01

330

Materials issues in fusion reactors  

NASA Astrophysics Data System (ADS)

The world scientific community is presently engaged in one of the toughest technological tasks of the current century, namely, exploitation of nuclear fusion in a controlled manner for the benefit of mankind. Scientific feasibility of controlled fusion of the light elements in plasma under magnetic confinement has already been proven. International efforts in a coordinated and co-operative manner are presently being made to build ITER - the International Thermonuclear Experimental Reactor - to test, in this first step, the concept of 'Tokamak' for net fusion energy production. To exploit this new developing option of making energy available through the route of fusion, India too embarked on a robust fusion programme under which we now have a working tokamak - the Aditya and a steady state tokamak (SST-1), which is on the verge of functioning. The programme envisages further development in terms of making SST-2 followed by a DEMO and finally the fusion power reactor. Further, with the participation of India in the ITER program in 2005, and recent allocation of half - a - port in ITER for placing our Lead - Lithium Ceramic Breeder (LLCB) based Test Blanket Module (TBM), meant basically for breeding tritium and extracting high grade heat, the need to understand and address issues related to materials for these complex systems has become all the more necessary. Also, it is obvious that with increasing power from the SST stages to DEMO and further to PROTOTYPE, the increasing demands on performance of materials would necessitate discovery and development of new materials. Because of the 14.1 MeV neutrons that are generated in the D+T reaction exploited in a tokamak, the materials, especially those employed for the construction of the first wall, the diverter and the blanket segments, suffer crippling damage due to the high He/dpa ratios that result due to the high energy of the neutrons. To meet this challenge, the materials that need to be developed for the tokamaks are steels for the first wall and other structurals, copper alloys for the heat sink, and beryllium for facing the plasma. For the TBMs, the materials that need to be developed include beryllium and/or beryllium-titanium alloys for neutron multiplication, lithium-bearing compounds for tritium generation, and the liquid metal coolants like lead-lithium eutectic in which lead acts as a neutron multiplier and lithium as a tritium breeder. The other materials that need attention of the materials scientists include superconductors made of NbTi, Nb3Sn and Nb3Al for the tokamaks, coatings or ceramic inserts to offset the effect of corrosion and the MHD in liquid metal cooled TBMs, and a host of other materials like nano-structured materials, special adhesives and numerous other alloys and compounds. Apart from this, the construction of the tokamaks would necessitate development of methodologies of joining the selected materials. This presentation would deal with the issues related to the development, characterization and qualification of both the structural as well as the functional materials required to carry forward the challenging task of harnessing fusion energy for use of mankind in engineered systems.

Suri, A. K.; Krishnamurthy, N.; Batra, I. S.

2010-02-01

331

A fusion transmutation of waste reactor  

Microsoft Academic Search

A design concept and the performance characteristics for a fusion transmutation of waste reactor (FTWR)—a sub-critical fast reactor driven by a tokamak fusion neutron source—are presented. The present design concept is based on nuclear, processing and fusion technologies that either exist or are at an advanced stage of development and on the existing tokamak plasma physics database. A FTWR, operating

W. M Stacey; J Mandrekas; E. A Hoffman; G. P Kessler; C. M Kirby; A. N Mauer; J. J Noble; D. M Stopp; D. S Ulevich

2002-01-01

332

Magnetic Confinement Fusion at the Crossroads  

E-print Network

~ pressure2 100 10 1 10-1 10-2 10-3 102 101 103 102 10 1 103 104 105 Temperature (keV) Powerdensity(MWm-3 ) Pressure(atm) D-T D-D Bremsstrahlung Pressure nD = nT = 5 x 1019m-3 #12;MGB / UT / 070307 6 Three Fusion, proposed fusion-bomb concept to Beria, and gridded electrostatic confinement for fusion energy ­ Sent

Princeton Plasma Physics Laboratory

333

Nuclear Fusion: A Solution to the GlobalNuclear Fusion: A Solution to the Global Energy CrisisEnergy Crisis  

E-print Network

Nuclear Fusion: A Solution to the GlobalNuclear Fusion: A Solution to the Global Energy Crisis.maclellan@strath.ac.uk Introduction and Motivation What is Nuclear Fusion? Laser Plasma Interactions The world, and particularly is harnessing the power of nuclear fusion. It is however, extremely difficult to sustain a fusion reaction

Strathclyde, University of

334

Fusion energy Fusion powers the Sun, and all stars, in which light nuclei fuse together at high temperatures  

E-print Network

Fusion energy · Fusion powers the Sun, and all stars, in which light nuclei fuse together at high temperatures (15 million degrees) releasing a large amount of energy. · The aim of fusion research is to use fusion to produce power on earth. · The most promising approach to fusion power is based on the `tokamak

335

D-Fusion: a Distinctive Fusion Calculus Michele Boreale1, Maria Grazia Buscemi2, and Ugo Montanari2  

E-print Network

D-Fusion: a Distinctive Fusion Calculus Michele Boreale1, Maria Grazia Buscemi2, and Ugo Montanari2 Informatica, Universit`a di Pisa, Italy. boreale@dsi.unifi.it {buscemi,ugo}@di.unipi.it Abstract. Fusion of a new calculus, D-Fusion, with two binders, and . We show that D-Fusion is strictly more expressive

Parrow, Joachim

336

Overview of European PR Efforts on Fusion  

NASA Astrophysics Data System (ADS)

The poster presents an overview of a fusion exhibit used for the teachers' day in Washington DC last spring and of the itinerant "Fusion-Expo", organized by the European Commission and the EURATOM Associations. The Washington exhibit gives a concise intro on fusion and on fusion R + D in the European Union. The "Fusion-Expo" is more comprehensive and contains mock-ups of existing fusion devices, multimedia presentations and video's. It consists of: (i) an introduction on fusion and the need for fusion (ii) an overview of magnetic and inertial confinement systems and (iii) a technological section. This exhibit has been on display in more than 20 European Cities. An updated version has been produced recently, taking into account the experience and reactions of the public of the past years. Handouts and brochures on both will be available. In addition there will be various leaflets currently used in Europe to increase the public awareness on fusion in general, and on the tremendous progress of the last decade with as highlight the deuterium-tritium results of TFTR and the ones obtained recently on JET.

Ongena, Jef; van Oost, Guido

1998-11-01

337

Multisensor data fusion with disparate data sources  

NASA Astrophysics Data System (ADS)

In many instances, sensing tasks are best addressed with multiple sensing modalities. However, fusion of the outputs of disparate sensor systems presents a significant challenge to forming a cohesive sensing system. A discussion of strategies for fusion of disparate sensor data is presented and illustrated with examples of real time and retrospective data fusion for multisensor systems. The first example discussed is a real-time system for situational awareness and the detection of damage control events in ship compartments. The second example is a retrospective data fusion framework for a multisensor system for the detection of buried unexploded ordnance at former bomb and target ranges.

Minor, Christian P.; Hammond, Mark H.; Johnson, Kevin J.; Rose-Pehrsson, Susan L.

2010-04-01

338

Signaling Mechanisms in Mammalian Myoblast Fusion  

NSDL National Science Digital Library

Skeletal muscles are formed by the fusion of multiple myoblasts during development. Myoblast fusion is also essential for the growth and repair of injured myofibers. Recent investigations have shown that the process of myoblast fusion involves the activation of several cell signaling pathways, including those mediated by nuclear factor κB, mitogen-activated protein kinases, Wnt, calcineurin–nuclear factor of activated T cells c2, transforming growth factor–β–Smad4, and the Rho guanosine triphosphatases. In this Review, which contains 2 figures and 84 references, we summarize the mechanisms by which the activation of these signaling pathways stimulates myoblast fusion.

Ashok Kumar (University of Louisville;School of Medicine REV); Sajedah M. Hindi (University of Louisville;School of Medicine REV); Marjan M. Tajrishi (University of Louisville;School of Medicine REV)

2013-04-23

339

Data Registration and Fusion for Cardiac Applications.  

E-print Network

??The registration and fusion of information from multiple cardiac image modalities such as magnetic resonance imaging (MRI), X-ray computed tomography (CT), positron emission tomography (PET)… (more)

Mäkelä, Timo

2003-01-01

340

Data registration and fusion for cardiac applications.  

E-print Network

??The registration and fusion of information from multiple cardiac image modalities such as magnetic resonance imaging (MRI), X-ray computed tomography (CT), positron emission tomography (PET)… (more)

Mäkelä, Timo

2003-01-01

341

Ontological issues in higher levels of information fusion: user refinement of the fusion process  

Microsoft Academic Search

Real-world data fusion systems process at the lowest level and combine data to a usable form for the human at the highest level. The functional role of the data fusion system is to provide timely and accurate data to the user. The focus of this paper is to address the user needs for a fusion system based on the ontological

Erik P. Blasch; S. Piano

2003-01-01

342

Stochastic Fusion Simulations and Experiments Suggest Passive and Active Roles of Hemagglutinin during Membrane Fusion  

E-print Network

Stochastic Fusion Simulations and Experiments Suggest Passive and Active Roles of Hemagglutinin during Membrane Fusion Donald W. Lee, Vikram Thapar, Paulette Clancy, and Susan Daniel* School the host cell cytoplasm by fusing the viral and host membrane together. Fusion is mediated by hemagglutinin

Daniel, Susan

343

The Heavy Ion Fusion Science Virtual National Laboratory Overview of Heavy Ion Fusion / High Energy  

E-print Network

11/29/2007 The Heavy Ion Fusion Science Virtual National Laboratory 1 Overview of Heavy Ion Fusion / High Energy Density Laboratory Physics * B. Grant Logan On behalf of the Heavy Ion Fusion Science Virtual National Laboratory** (HIFS-VNL)** LBNL, LLNL, PPPL Presentation in two parts: 1. Heavy ion driven

344

National Research Centre "Kurchatov Institute" Progress in Magnetic Fusion TechnologyProgress in Magnetic Fusion Technology  

E-print Network

on Magnetic Fusion Technology FUSION ENGINEERING INTEGRATION&POWER PLANT DESIGNFUSION ENGINEERING, INTEGRATION&POWER PLANT DESIGN FUSION NUCLEAR SCIENCE MATERIAL TECHNOLOGY SYSTEMS SAFETY ECONOMIC of prototypes and parts Higher activity in DEMO and FNSF G h f FT ib i MFT i i OV&OV/PGrowth of FT contributions

345

Training The Next Generation Of Fusion Scientists And Engineers: Summer High School Fusion Science Workshop  

Microsoft Academic Search

The goal of the education and outreach activities of the Hampton University Center for Fusion Research and Training (HU CFRT) is to create a high school-to-Ph.D. pipeline in plasma physics, fusion science, and related sciences for underrepresented minorities and female students. The HU CFRT Summer High School Fusion Research Workshop is an integral component of this pipeline. This workshop has

Alkesh Punjabi

2005-01-01

346

Introduction to Nuclear Fusion Power and the Design of Fusion Reactors. An Issue-Oriented Module.  

ERIC Educational Resources Information Center

This three-part module focuses on the principles of nuclear fusion and on the likely nature and components of a controlled-fusion power reactor. The physical conditions for a net energy release from fusion and two approaches (magnetic and inertial confinement) which are being developed to achieve this goal are described. Safety issues associated…

Fillo, J. A.

347

Fusion Engineering and Design 41 (1998) 337347 Prospects and issues for commercial fusion power systems  

E-print Network

Abstract As one alternative source of energy for the future, fusion power will be required to demonstrate of many alternative energy sources, fusion should and will be subjected to a rigorous set of requirements and requirements As one of the alternative sources of energy, fusion should and will be required to demonstrate

California at San Diego, University of

348

76 FR 40714 - Fusion Energy Sciences Advisory Committee  

Federal Register 2010, 2011, 2012, 2013, 2014

...DEPARTMENT OF ENERGY Fusion Energy Sciences Advisory Committee AGENCY...This notice announces a meeting of the Fusion Energy Sciences Advisory Committee. The...Designated Federal Officer, Office of Fusion Energy Sciences; U.S. Department...

2011-07-11

349

21 CFR 886.1880 - Fusion and stereoscopic target.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 2013-04-01 false Fusion and stereoscopic target. 886.1880...DEVICES Diagnostic Devices § 886.1880 Fusion and stereoscopic target. (a) Identification. A fusion and stereoscopic target is a device...

2013-04-01

350

78 FR 15937 - Fusion Energy Sciences Advisory Committee  

Federal Register 2010, 2011, 2012, 2013, 2014

...DEPARTMENT OF ENERGY Fusion Energy Sciences Advisory Committee AGENCY...This notice announces a meeting of the Fusion Energy Sciences Advisory Committee. The...Designated Federal Officer, Office of Fusion Energy Sciences; U.S. Department...

2013-03-13

351

21 CFR 888.3080 - Intervertebral body fusion device.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 false Intervertebral body fusion device. 888.3080 Section 888...Devices § 888.3080 Intervertebral body fusion device. (a) Identification . An intervertebral body fusion device is an implanted single...

2011-04-01

352

21 CFR 888.3080 - Intervertebral body fusion device.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 false Intervertebral body fusion device. 888.3080 Section 888...Devices § 888.3080 Intervertebral body fusion device. (a) Identification . An intervertebral body fusion device is an implanted single...

2010-04-01

353

21 CFR 886.1880 - Fusion and stereoscopic target.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 2012-04-01 false Fusion and stereoscopic target. 886.1880...DEVICES Diagnostic Devices § 886.1880 Fusion and stereoscopic target. (a) Identification. A fusion and stereoscopic target is a device...

2012-04-01

354

21 CFR 886.1880 - Fusion and stereoscopic target.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 2014-04-01 false Fusion and stereoscopic target. 886.1880...DEVICES Diagnostic Devices § 886.1880 Fusion and stereoscopic target. (a) Identification. A fusion and stereoscopic target is a device...

2014-04-01

355

21 CFR 886.1880 - Fusion and stereoscopic target.  

Code of Federal Regulations, 2010 CFR

...2010-04-01 2010-04-01 false Fusion and stereoscopic target. 886.1880...DEVICES Diagnostic Devices § 886.1880 Fusion and stereoscopic target. (a) Identification. A fusion and stereoscopic target is a device...

2010-04-01

356

78 FR 2259 - Fusion Energy Sciences Advisory Committee  

Federal Register 2010, 2011, 2012, 2013, 2014

...DEPARTMENT OF ENERGY Fusion Energy Sciences Advisory Committee AGENCY...This notice announces a meeting of the Fusion Energy Sciences Advisory Committee. The...Designated Federal Officer, Office of Fusion Energy Sciences; U.S. Department...

2013-01-10

357

21 CFR 888.3080 - Intervertebral body fusion device.  

Code of Federal Regulations, 2014 CFR

...2014-04-01 false Intervertebral body fusion device. 888.3080 Section 888...Devices § 888.3080 Intervertebral body fusion device. (a) Identification. An intervertebral body fusion device is an implanted single...

2014-04-01

358

21 CFR 888.3080 - Intervertebral body fusion device.  

Code of Federal Regulations, 2012 CFR

...2012-04-01 false Intervertebral body fusion device. 888.3080 Section 888...Devices § 888.3080 Intervertebral body fusion device. (a) Identification . An intervertebral body fusion device is an implanted single...

2012-04-01

359

75 FR 8685 - Fusion Energy Sciences Advisory Committee  

Federal Register 2010, 2011, 2012, 2013, 2014

...DEPARTMENT OF ENERGY Fusion Energy Sciences Advisory Committee AGENCY...This notice announces a meeting of the Fusion Energy Sciences Advisory Committee. The...CONTACT: Albert L. Opdenaker, Office of Fusion Energy Sciences; U.S. Department...

2010-02-25

360

21 CFR 888.3080 - Intervertebral body fusion device.  

Code of Federal Regulations, 2013 CFR

...2013-04-01 false Intervertebral body fusion device. 888.3080 Section 888...Devices § 888.3080 Intervertebral body fusion device. (a) Identification . An intervertebral body fusion device is an implanted single...

2013-04-01

361

21 CFR 886.1880 - Fusion and stereoscopic target.  

Code of Federal Regulations, 2011 CFR

...2011-04-01 2011-04-01 false Fusion and stereoscopic target. 886.1880...DEVICES Diagnostic Devices § 886.1880 Fusion and stereoscopic target. (a) Identification. A fusion and stereoscopic target is a device...

2011-04-01

362

Fusion action systems by Matthew J.K. Gelvin.  

E-print Network

The study of fusion first arose in the local theory of finite groups. Puig abstracted the fusion data of a finite group to the notion of fusion system, an object that reflects local data in more abstract algebraic settings, ...

Gelvin, Matthew J. K. (Matthew Justin Karcher)

2010-01-01

363

Long Pulse Fusion Physics Experiments Without Superconducting Electromagnets  

E-print Network

Long Pulse Fusion Physics Experiments Without Superconducting Electromagnets Robert D. Woolley fusion physics experiments can be performed economically via resistive electromagnets designed for thermally steady-state operation. Possible fusion experiments using resistive electromagnets include long

364

Long Pulse Fusion Physics Experiments Without Superconducting Electromagnets  

E-print Network

Long Pulse Fusion Physics Experiments Without Superconducting Electromagnets Robert D. Woolley fusion physics experiments can be performed economically via resistive electromagnets designed for thermally steady­state operation. Possible fusion experiments using resistive electromagnets include long

365

Magnetized Target Fusion in Advanced Propulsion Research  

NASA Technical Reports Server (NTRS)

The Magnetized Target Fusion (MTF) Propulsion lab at NASA Marshall Space Flight Center in Huntsville, Alabama has a program in place that has adopted to attempt to create a faster, lower cost and more reliable deep space transportation system. In this deep space travel the physics and development of high velocity plasma jets must be understood. The MTF Propulsion lab is also in attempt to open up the solar system for human exploration and commercial use. Fusion, as compared to fission, is just the opposite. Fusion involves the light atomic nuclei combination to produce denser nuclei. In the process, the energy is created by destroying the mass according to the distinguished equation: E = mc2 . Fusion energy development is being pursued worldwide as a very sustainable form of energy that is environmentally friendly. For the purposes of space exploration fusion reactions considered include the isotopes of hydrogen-deuterium (D2) and tritium (T3). Nuclei have an electrostatic repulsion between them and in order for the nuclei to fuse this repulsion must be overcome. One technique to bypass repulsion is to heat the nuclei to very high temperatures. The temperatures vary according to the type of reactions. For D-D reactions, one billion degrees Celsius is required, and for D-T reactions, one hundred million degrees is sufficient. There has to be energy input for useful output to be obtained form the fusion To make fusion propulsion practical, the mass, the volume, and the cost of the equipment to produce the reactions (generally called the reactor) need to be reduced by an order of magnitude or two from the state-of-the-art fusion machines. Innovations in fusion schemes are therefore required, especially for obtaining thrust for propulsive applications. Magnetized target fusion (MTF) is one of the innovative fusion concepts that have emerged over the last several years. MSFC is working with Los Alamos National Laboratory and other research groups in studying the underlying principles involved in MTF. Magnetized Target Fusion is an attempt to combine MCF (magnetic confinement fusion) for energy confinement and ICF (inertial confinement fusion) for efficient compression heating and wall free containment of the fusing plasma. It also seeks to combine the best features to these two main commonplace approaches to fusion.

Cylar, Rashad

2003-01-01

366

Curvelet based hyperspectral image fusion  

NASA Astrophysics Data System (ADS)

Hyperspectral imagery typically possesses high spectral resolution but low spatial resolution. One way to enhance the spatial resolution of a hyperspectral image is to fuse its spectral information and the spatial information of another high resolution image. In this paper, we propose a novel image fusion strategy for hyperspectral image and high spatial resolution panchromatic image, which is based on the curvelet transform. Firstly, determine a synthesized image with the specified RGB bands of the original hyperspectral images according to the optimal index factor (OIF) model. Then use the IHS transform to extract the intensity component of the synthesized image. After that, the histogram matching is performed between the intensity component and the panchromatic image. Thirdly, the curvelet transform is applied to decompose the two source images (the intensity component and the panchromatic image) in different scales and directions. Different fusion strategies are applied to coefficients in various scales and directions. Finally, the fused image is achieved by the inverse IHS transform. The experimental result shows that the proposed method has a superior performance. Comparing with the traditional methods such as the PCA transform, wavelet-based or pyramid-based methods and the multi-resolution fusion methods (shearlet or contourlet decomposition), the fused image achieves the highest entropy index and average gradient value. While providing a better human visual quality, a good correlation coefficient index indicates that the fused image keeps good spectral information. Both visual quality and objective evaluation criteria demonstrate that this method can well preserve the spatial quality and the spectral characteristics.

Wang, Sha; Feng, Hua-jun; Xu, Zhi-hai; Li, Qi; Chen, Yue-ting

2013-08-01

367

Magnetized Target Fusion Driven by Plasma Liners  

NASA Technical Reports Server (NTRS)

Magnetized target fusion is an emerging, relatively unexplored approach to fusion for electrical power and propulsion application. The physical principles of the concept are founded upon both inertial confinement fusion (ICF) and magnetic confinement fusion (MCF). It attempts to combine the favorable attributes of both these orthogonal approaches to fusion, but at the same time, avoiding the extreme technical challenges of both by exploiting a fusion regime intermediate between them. It uses a material liner to compress, heat and contain the fusion reacting plasma (the target plasma) mentally. By doing so, the fusion burn could be made to occur at plasma densities as high as six orders of magnitude higher than conventional MCF such as tokamak, thus leading to an approximately three orders of magnitude reduction in the plasma energy required for ignition. It also uses a transient magnetic field, compressed to extremely high intensity (100's T to 1000T) in the target plasma, to slow down the heat transport to the liner and to increase the energy deposition of charged-particle fusion products. This has several compounding beneficial effects. It leads to longer energy confinement time compared with conventional ICF without magnetized target, and thus permits the use of much lower plasma density to produce reasonable burn-up fraction. The compounding effects of lower plasma density and the magneto-insulation of the target lead to greatly reduced compressional heating power on the target. The increased energy deposition rate of charged-particle fusion products also helps to lower the energy threshold required for ignition and increasing the burn-up fraction. The reduction in ignition energy and the compressional power compound to lead to reduced system size, mass and R&D cost. It is a fusion approach that has an affordable R&D pathway, and appears attractive for propulsion application in the nearer term.

Thio, Y. C. Francis; Kirkpatrick, Ronald C.; Knapp, Charles E.; Rodgers, Stephen L. (Technical Monitor)

2002-01-01

368

Fusion Algebras of Logarithmic Minimal Models  

E-print Network

We present explicit conjectures for the chiral fusion algebras of the logarithmic minimal models LM(p,p') considering Virasoro representations with no enlarged or extended symmetry algebra. The generators of fusion are countably infinite in number but the ensuing fusion rules are quasi-rational in the sense that the fusion of a finite number of representations decomposes into a finite direct sum of representations. The fusion rules are commutative, associative and exhibit an sl(2) structure but require so-called Kac representations which are reducible yet indecomposable representations of rank 1. In particular, the identity of the fundamental fusion algebra is in general a reducible yet indecomposable Kac representation of rank 1. We make detailed comparisons of our fusion rules with the results of Gaberdiel and Kausch for p=1 and with Eberle and Flohr for (p,p')=(2,5) corresponding to the logarithmic Yang-Lee model. In the latter case, we confirm the appearance of indecomposable representations of rank 3. We also find that closure of a fundamental fusion algebra is achieved without the introduction of indecomposable representations of rank higher than 3. The conjectured fusion rules are supported, within our lattice approach, by extensive numerical studies of the associated integrable lattice models. Details of our lattice findings and numerical results will be presented elsewhere. The agreement of our fusion rules with the previous fusion rules lends considerable support for the identification of the logarithmic minimal models LM(p,p') with the augmented c_{p,p'} (minimal) models defined algebraically.

Jorgen Rasmussen; Paul A. Pearce

2007-09-21

369

From pure fusion to fusion-fission Demo tokamaks  

NASA Astrophysics Data System (ADS)

The major requirements for pure fusion tokamak reactors and tokamak-based fusion neutron sources (FNS) are analyzed together with possible paths from the present-day tokamak towards the FNS tokamak. The FNS are of interest for traditional fission reactors as a method of waste management by burning of long-lived transuranic radionuclides (minorities) and fission fuel breeding. The Russian fission community places several hard requirements on the quality of FNS suitable for the first step of the investigation program of minority burning and breeding. They are (a) a steady-state regime of neutron production (more than 80% of the operational time), (b) a neutron power flux density greater than >0.2 MW m-2, (c) a total surface integrated neutron power >10 MW. Among the different FNS projects, based on magnetically confined plasmas, only ‘classical tokamak’ is most likely to fulfill these requirements in the nearest future. Some of the most important improvements of the ‘classical tokamak’ needed for successful realization of the FNS are (1) decrease in Zeff (probably, by making use of lithium as a part of plasma-facing components), (2) He removal and closed loop DT fuel circulation, (3) increase in the energy of stationary injected neutral tritium beams up to 150-170 keV and (4) control of impurity contamination at the plasma center (probably, by local RF heating). These key issues are discussed.

Mirnov, S. V.

2013-04-01

370

Level 5 (User Refinement) issues supporting Information Fusion Management  

Microsoft Academic Search

Subsequent revisions to the Joint-Directors of Lab (JDL) model emphasize the differentiation between fusion (estimation) and sensor management (control). Two diverging groups include one pressing for fusion automation (JDL revisions) and one advocating the role of the user (user-fusion model). The center of debate is real-world delivery of fusion systems which requires presenting fusion results for knowledge representation (fusion estimation)

Erik Blasch

2006-01-01

371

Interplanetary propulsion using inertial fusion  

NASA Technical Reports Server (NTRS)

Inertial fusion can be used to power spacecraft within the solar system and beyond. Such spacecraft have the potential for short duration manned mission performance exceeding other technologies. A study was conducted to assess the systems aspects of inertial as applied to such missions, based on the conceptual engine design of Hyde (1983). The required systems for an entirely new spacecraft design called VISTA that is based on the use of DT fuel is described. Preliminary design details are given for the power conversion and power conditioning systems for manned missions to Mars of total duration of about 100 days.

Orth, Charles D.; Hoffman, Nate; Murray, Kathy; Klein, Gail; Diaz, Franklin Chang

1987-01-01

372

Mitochondrial fusion through membrane automata.  

PubMed

Studies have shown that malfunctions in mitochondrial processes can be blamed for diseases. However, the mechanism behind these operations is yet not sufficiently clear. In this work we present a novel approach to describe a biomolecular model for mitochondrial fusion using notions from the membrane computing. We use a case study defined in BioAmbient calculus and we show how to translate it in terms of a P automata variant. We combine brane calculi with (mem)brane automata to produce a new scheme capable of describing simple, realistic models. We propose the further use of similar methods and the test of other biomolecular models with the same behaviour. PMID:25417022

Giannakis, Konstantinos; Andronikos, Theodore

2015-01-01

373

Nuclear Fusion Award 2010 speech Nuclear Fusion Award 2010 speech  

NASA Astrophysics Data System (ADS)

Following the suggestion of Earl Marmar in 1995, I installed a compact von Hamos type x-ray spectrometer (originally built with Elisabeth Rachlew and Jan Kallne) on a tangentially viewing port on the Alcator C-Mod tokamak. The spectrometer views the plasma through a 2 cm diameter hole, and is tuned to H-like argon, suitable for passive measurement of the core toroidal rotation velocity from the Doppler shift. It soon became evident that the rotation in Ohmic L-mode discharges, while for the most part directed counter-current, depends in a very complicated fashion on plasma parameters, notably the electron density, current and magnetic configuration. The rotation can even flip sign for almost no apparent reason! In Ohmic and ion cyclotron range of frequencies (ICRF) heated H-mode plasmas the rotation is in the co-current direction and has a relatively simple dependence on plasma parameters, proportional to the stored energy normalized to the current. Rotation velocities as high as 130 km s-1 have been observed without external momentum input. In dimensionless terms this intrinsic (or spontaneous rotation) depends on the normalized plasma pressure. The association of toroidal rotation with plasma pressure in ICRF H-modes was first observed by Lars-Goran Eriksson in JET discharges. Similar results were subsequently reported for Tore Supra enhanced confinement plasmas. In the early 2000s concerns began to surface about the lack of substantial neutral beam driven rotation in ITER, and intrinsic rotation became a topic of interest in the ITPA Transport Group. Through that connection, similar observations from DIII-D, TCV and JT-60U were added to the growing list. A database of intrinsic rotation observations was assembled with the goal of extrapolating to the expected values for ITER. Both dimensional and dimensionless scalings were developed and formed the backbone of the 2007 Nuclear Fusion paper. I gratefully acknowledge the important contributions to this paper from Alex Ince-Cushman, John deGrassie, Lars-Goran Eriksson, Yoshiteru Sakamoto, Andrea Scarabosio and Yuri Podpaly, as well as the other coauthors. I would like to express my sincere appreciation to Earl Marmar, Martin Greenwald and Miklos Porkolab at MIT for continued support of this work, as well as to the entire C-Mod team. This award was made possible due to the insight of Mitsuru Kikuchi and the support of the IAEA through Werner Burkhart, and I am truly grateful to both of them. Many thanks as well to the outstanding staff at Nuclear Fusion. It is a distinct honor to be included in the group of previous winners: Tim Luce, Clemente Angioni, Todd Evans and Steve Sabbagh. It is also a great honor to be considered alongside the 2010 nominees: Phil Snyder, Sibylle Guenter, Maiko Yoshida, Hajime Urano, Fulvio Zonca, Erik Garcia, Costanza Maggi, Hartmut Zohm, Thierry Loarer and Bruce Lipschultz. Finally, I would like to thank the readers of Nuclear Fusion for the many citations. John Rice 2010 Nuclear Fusion Award winner Plasma Science and Fusion Center, MIT, Cambridge, MA, USA

Rice, John

2011-01-01

374

Scientific Breakeven for Fusion Energy For the past 40 years, the IFE fusion research community has adopted: achieving a fusion gain of 1 as  

E-print Network

Scientific Breakeven for Fusion Energy For the past 40 years, the IFE fusion research community has adopted: achieving a fusion gain of 1 as the demonstration of scientific breakeven, where gain was defined, with fusion energy equal to laser energy. The LLNL definition of scientific breakeven was also published in

375

Fusion Nuclear Science and Technology ProgramFusion Nuclear Science and Technology Program Issues and Strategy for Fusion Nuclear Science Facility (FNSF)  

E-print Network

Need for Fusion Nuclear Science and Technology ProgramFusion Nuclear Science and Technology Program ­Issues and Strategy for Fusion Nuclear Science Facility (FNSF) ­Key R&D Areas to begin NOW (modeling 12, 2010 #12;Fusion Nuclear Science and Technology (FNST) FNST is the science engineering technology

Abdou, Mohamed

376

Fusion Engineering and Design 41 (1998) 365370 Overview of ARIES-RS tokamak fusion power plant1  

E-print Network

Fusion Engineering and Design 41 (1998) 365­370 Overview of ARIES-RS tokamak fusion power plant10920-3796(97)00153-1 #12;F. Najmabadi et al. / Fusion Engineering and Design 41 (1998) 365­370366 Five

Najmabadi, Farrokh

377

Future Direction of National Fusion Research Tentative translation to English  

E-print Network

Design of Fusion Research ---------------------------------2 (1) Necessity of Centralization Research Centralization Plan -------------------------------------------------------4 (1) Evaluation of Existing Fusion Research Programs --------------------------------4 (2) Centralized Research Programs

378

Measuring time of flight of fusion products in an inertial electrostatic confinement fusion device for spatial profiling of fusion reactions.  

PubMed

A new diagnostic has been developed that uses the time of flight (TOF) of the products from a nuclear fusion reaction to determine the location where the fusion reaction occurred. The TOF diagnostic uses charged particle detectors on opposing sides of the inertial electrostatic confinement (IEC) device that are coupled to high resolution timing electronics to measure the spatial profile of fusion reactions occurring between the two charged particle detectors. This diagnostic was constructed and tested by the University of Wisconsin-Madison Inertial Electrostatic Confinement Fusion Group in the IEC device, HOMER, which accelerates deuterium ions to fusion relevant energies in a high voltage (?100 kV), spherically symmetric, electrostatic potential well [J. F. Santarius, G. L. Kulcinski, R. P. Ashley, D. R. Boris, B. B. Cipiti, S. K. Murali, G. R. Piefer, R. F. Radel, T. E. Radel, and A. L. Wehmeyer, Fusion Sci. Technol. 47, 1238 (2005)]. The TOF diagnostic detects the products of D(d,p)T reactions and determines where along a chord through the device the fusion event occurred. The diagnostic is also capable of using charged particle spectroscopy to determine the Doppler shift imparted to the fusion products by the center of mass energy of the fusion reactants. The TOF diagnostic is thus able to collect spatial profiles of the fusion reaction density along a chord through the device, coupled with the center of mass energy of the reactions occurring at each location. This provides levels of diagnostic detail never before achieved on an IEC device. PMID:23556815

Donovan, D C; Boris, D R; Kulcinski, G L; Santarius, J F; Piefer, G R

2013-03-01

379

Method of controlling fusion reaction rates  

DOEpatents

A method of controlling the reaction rates of the fuel atoms in a fusion reactor comprises the step of polarizing the nuclei of the fuel atoms in a particular direction relative to the plasma confining magnetic field. Fusion reaction rates can be increased or decreased, and the direction of emission of the reaction products can be controlled, depending on the choice of polarization direction.

Kulsrud, Russell M. (Princeton, NJ); Furth, Harold P. (Princeton, NJ); Valeo, Ernest J. (Princeton Junction, NJ); Goldhaber, Maurice (Bayport, NY)

1988-01-01

380

A fusion based plasma propulsion system  

NASA Technical Reports Server (NTRS)

The Fusion Plasma Propulsion System scoping study was performed to investigate the possibilities of a fusion powered plasma propulsion system for space applications. Specifically, it was to be compared against existing electric propulsion concepts for a manned Mars mission. Design parameters consist of 1000 N thrust for 500 days, and the minimum mass possible. This investigation is briefly presented and conclusions drawn.

George, J. A.; Anderson, B.; Bryant, D.; Creese, C.; Djordjevic, V.; Peddicord, K. L.

1987-01-01

381

Ch. 37, Inertial Fusion Energy Technology  

Microsoft Academic Search

Nuclear fission, nuclear fusion, and renewable energy (including biofuels) are the only energy sources capable of satisfying the Earth's need for power for the next century and beyond without the negative environmental impacts of fossil fuels. Substantially increasing the use of nuclear fission and renewable energy now could help reduce dependency on fossil fuels, but nuclear fusion has the potential

Moses

2010-01-01

382

Graft inserter for anterior cervical fusion.  

PubMed

The authors have developed a simple instrument for graft insertion in anterior cervical fusion. This device obviates the need for screw distraction of the adjacent vertebrae or the use of an impactor for insertion. This device simplifies graft insertion where the disc space is narrow, particularly in multilevel fusions, and reduces the risk of over-penetration of the graft. PMID:24974192

Hitchon, Patrick W; Kumar, Rajinder; Viljoen, Stephanus; Dahdaleh, Nader S

2014-11-01

383

Multisensor image fusion using the wavelet transform  

Microsoft Academic Search

The goal of image fusion is to integrate complementary information from multisensor data such that the new images are more suitable for the purpose of human visual perception and computer-processing tasks such as segmentation, feature extraction, and object recognition. This paper presents an image fusion scheme which is based on the wavelet transform. The wavelet transforms of the input images

Hui Li; B. S. Manjunath; Sanjit K. Mitra

1995-01-01

384

SOAR: Space orbiting advanced fusion power reactor  

Microsoft Academic Search

The Space Orbiting Advanced Fusion Power Reactor (SOAR) is described. The SOAR reactor delivers 250 to 1000 MWe for at least 10 minutes from a D\\/He-3 plasma. About 99 percent of the fusion energy is in charged particles, and much of this energy is electrostatically converted directly into electricity at high efficiency. Advanced materials and shielding techniques allow SOAR to

J. F. Santarius; G. L. Kulcinski; H. Attaya; M. L. Corradini; L. A. El-Guebaly; G. A. Emmert; C. W. Maynard; M. E. Sawan; I. N. Sviatoslavsky; W. F. Vogelsang

1987-01-01

385

Sean Finnegan & Ann Satsangi Fusion Energy Sciences  

E-print Network

& Inertial Fusion Energy Science #12;summary 2 Fusion Energy Sciences is pursuing a strategic vision to provide the · Stability, · Flexibility, and · Growth necessary to develop and strengthen an autonomous 1 million atmospheres or 1 Mbar".* *Systems in which free electrons play a significant role

386

Introduction to Fusion Energy Jerry Hughes  

E-print Network

Burn `em Biomass Fossil fuels #12;What are the prospects for nuclear fusion on Earth? · Scientists more #12;18 What Are The World's Energy Options? Nothing obviously easy Burning fossil fuels are serious about reducing fossil fuel burning; at least until fusion available) Biofuels ­ can this be made

387

Source diversity and feature-level fusion  

Microsoft Academic Search

We briefly review the various models proposed for data fusion systems. A common theme of these models is the existence of multiple levels of processing within the data fusion process. We highlight some of the issues which emerge from using such a layered approach, in particular the selection of sources at each level which are both relevant and complementary. The

M. D. Bedworth

1999-01-01

388

Fusion Power Associates 34th Annual Meeting  

E-print Network

Fusion Power Associates 34th Annual Meeting Washington, DC 11 December 2013 Perspectives Laser power ~ EL Pulse length ~ EL Mass fuel ~ EL 1/3 1/3 1/3 2/3 Performance metrics include Px (atm, 165001 (2010). **R. Betti, "Theory of Ignition and Hydro-Equivalence for Inertial Confinement Fusion

389

Ion beam analysis for fusion energy research  

Microsoft Academic Search

Proposed next-step devices for development of fusion energy present a major increase in the energy content and duration of plasmas far beyond those encountered in existing machines. This increases the importance of controlling interactions between the fusion plasma and first-wall materials. These interactions change the wall materials and strongly affect the core plasma conditions. Two critical processes are the erosion

Wampler; William R

2003-01-01

390

Ion beam analysis for fusion energy research  

Microsoft Academic Search

Proposed next-step devices for development of fusion energy present a major increase in the energy content and duration of plasmas far beyond those encountered in existing machines. This increases the importance of controlling interactions between the fusion plasma and first-wall materials. These interactions change the wall materials and strongly affect the core plasma conditions. Two critical processes are the erosion

W. R. Wampler

2004-01-01

391

Optimization of tritium transfer in fusion reactor  

Microsoft Academic Search

Tritium transfer in fusion reactor is one of major risk of contamination in fusion plant, as well for environment impact as for worker inside plant. The main purposes of this study is to calculate tritium concentration in each containment, taking into account containment design, leakage rate of tritium contaminated cooled water and atmospheric detritiation system. It is tried to optimize

M. Djerassi; F. Rancillac

1985-01-01

392

Photographing paintings by image fusion Gloria Haro  

E-print Network

Photographing paintings by image fusion Gloria Haro Dept. of Information and Communications a quality photograph of a painting by multi-image fusion methods. The problem is particularly challenging in most photographs of paintings. A fully automatic image processing chain is described that, starting

393

EURATOM/CCFE Fusion Association Annual Report  

E-print Network

and expense involved. But there aren't many other long-term energy options on the table; the world needs showing the steps we need to take to put fusion power on the grid by 2050. The European Fusion Development

394

Minimally invasive 360° instrumented lumbar fusion  

Microsoft Academic Search

A retrospective preliminary study was undertaken of combined minimally invasive instrumented lumbar fusion utilizing the BERG (balloon-assisted endoscopic retroperitoneal gasless) approach ¶anteriorly, and a posterior small-incision approach with translaminar screw fixation and posterolateral ¶fusion. The study aimed to quantify the clinical and radiological results using this combined technique. The traditional minimally invasive approach to the anterior lumbar spine involves gas

John S. Thalgott; Albert K. Chin; John A. Ameriks; Frank T. Jordan; James M. Giuffre; Kay Fritts; Marcus Timlin

2000-01-01

395

Mass Producing Targets for Nuclear Fusion  

NASA Technical Reports Server (NTRS)

Metal-encapsulating technique advances prospects of controlling nuclear fusion. Prefilled fusion targets form at nozzle as molten metal such as tin flows through outer channel and pressurized deuterium/tritium gas flows through inner channel. Molten metal completely encloses gas charge as it drops off nozzle.

Wang, T. G.; Elleman, D. D.; Kendall, J. M.

1983-01-01

396

Use of the novel ANSPACH bone collector for bone autograft in anterior cervical discectomy and cage fusion  

Microsoft Academic Search

Background  The use of interbody cages with bone autograft following anterior cervical discectomy is well documented. The use of high-speed\\u000a drills in the drilling of the posterior osteophyte results in the production of bone dust with viable osteophytes. We report\\u000a the use of the ANSPACH bone collector device, which can be connected to standard suction circuitry and used to collect this

Jinendra Ekanayake; Amjad Shad

2010-01-01

397

Fusion research: the past is prologue  

SciTech Connect

At this juncture fusion research can be viewed as being at a turning point, a time to review its past and to imagine its future. Today, almost 50 years since the first serious attempts to address the daunting problem of achieving controlled fusion, we have both an opportunity and a challenge. Some predictions place fusion research today at a point midway between its first inception and its eventual maturation - in the middle of the 21st century - when fusion would become a major source of energy. Our opportunity therefore is to assess what we have learned from 50 years of hard work and use that knowledge as a starting point for new and better approaches to solving the fusion problem. Our challenge is to prove the "50 more years" prophesy wrong, by finding ways to shorten the time when fusion power becomes a reality. The thesis will be advanced that in the magnetic confinement approach to fusion open-ended magnetic confinement geometries offer much in responding to the challenge. A major advantage of open systems is that, owing to their theoretically and experimentally demonstrated ability to suppress plasma instabilities of both the MHD and the high-frequency wave-particle variety, the confinement becomes predictable from "classical," i.e., Fokker-Planck-type analysis. In a time of straitened budgetary circumstances for magnetic fusion research now being faced in the United States, the theoretical tractability of mirror-based systems is a substantial asset. In pursuing this avenue it is also necessary to keep an open mind as to the forms that mirror-based fusion power plants might take. For example, one can look to the high-energy physics community for a possible model: This community has shown the feasibility of constructing large and complex particle accelerators using superconducting magnets, vacuum chambers and complicated particle-handling technology, housed in underground tunnels that are 20 or more kilometers long. In the paper examples of mirror-based fusion power systems resembling long "linear colliders" will be discussed. It is not the intent of this paper to present detailed proposals for next-generation experiments in magnetic fusion research, but rather to encourage a return to the ambiance of an earlier era of fusion research, when innovative thinking and a spirit of scientific adventure prevailed. In that way we can realistically build a new era of fusion research, an era that would be firmly undergirded by the scientific and technological foundation that was laid in fusion's first half-century.

Post, R F

1998-10-14

398

Plasma effects on resonant fusion  

NASA Astrophysics Data System (ADS)

I investigate the effects of plasma interactions on resonance-enhanced fusion rates in stars. Starting from basic principles we derive an expression for the fusion rate that can serve as a basis for discussion of approximation schemes The present state-of-the-art correction algorithms, based on the classical correlation function for the fusing particles and the classical energy shift for the resonant state, do not follow from this result, even as an approximation. The results of expanding in a perturbation solution for the case of a weakly coupled plasma are somewhat enlightening. But at this point we are at a loss as to how to do meaningful calculations in systems with even moderate plasma coupling strength. Examples where this can matter are the effect of a possible low-energy 12C+12C resonance on x-ray bursts from accreting neutron stars or on supernova 1A simulations, and the calculation of the triple ? rate in some of the more strongly coupled regions in which the process enters, such as accretion onto a neutron star.

Sawyer, R. F.

2012-11-01

399

Magnetic-fusion energy and computers  

SciTech Connect

The application of computers to magnetic fusion energy research is essential. In the last several years the use of computers in the numerical modeling of fusion systems has increased substantially. There are several categories of computer models used to study the physics of magnetically confined plasmas. A comparable number of types of models for engineering studies are also in use. To meet the needs of the fusion program, the National Magnetic Fusion Energy Computer Center has been established at the Lawrence Livermore National Laboratory. A large central computing facility is linked to smaller computer centers at each of the major MFE laboratories by a communication network. In addition to providing cost effective computing services, the NMFECC environment stimulates collaboration and the sharing of computer codes among the various fusion research groups.

Killeen, J.

1982-01-01

400

Public Relations on Fusion in Europe  

NASA Astrophysics Data System (ADS)

A summary will be presented of PR efforts on fusion energy research in Europe. A 3-D movie of a fusion research experimental reactor has been realized at the start of this year. It has been made entirely on virtual animation basis. Two versions exists, a short version of 3 min., as a video clip, and a longer version of nearly 8 min. Both could be viewed in 3D, using special projections and passive glasses or in normal VHS video projections. A new CD-ROM for individual and classroom use will be presented, discussing (i) the different energy forms, (ii) general principles of fusion, (iii) current research efforts and (iv) future prospects of fusion. This CD-ROM is now produced in English, German, French, Spanish, Italian and Portuguese Several new brochures and leaflets intended to increase the public awareness on fusion in Europe will be on display.

Ongena, J.; van Oost, G.; Paris, P. J.

2000-10-01

401

Mechanics of membrane fusion/pore formation.  

PubMed

Lipid bilayers play a fundamental role in many biological processes, and a considerable effort has been invested in understanding their behavior and the mechanism of topological changes like fusion and pore formation. Due to the time- and length-scale on which these processes occur, computational methods have proven to be an especially useful tool in their study. With their help, a number of interesting findings about the shape of fusion intermediates could be obtained, and novel hypotheses about the mechanism of topological changes and the involvement of peptides therein were suggested. In this work, we try to present a summary of these developments together with some hitherto unpublished results, featuring, among others, the shape of stalks and fusion pores, possible modes of action of the influenza HA fusion peptide and the SNARE protein complex, the mechanism of supported lipid bilayer formation by vesicle spreading, and the free energy and transition pathway of the fusion process. PMID:25087882

Fuhrmans, Marc; Marelli, Giovanni; Smirnova, Yuliya G; Müller, Marcus

2014-08-01

402

FusEdWeb: Fusion Education  

NSDL National Science Digital Library

The sun, which is a pretty average star, produces 100 million times more energy in a single second than we, as a global population, manage to muster in a solid year. How? Fusion. In a nutshell, fusion is the process of combining light nuclei. ItâÂÂs the process of converting mass into kinetic energy. This website from the Contemporary Physics Education Project seeks to demystify the obscurities of fusion through a variety of introductory and educational materials. Check out learned elucidations of Our Sun, Other Stars and Galaxies, Inertial Confinement, and Magnetic Confinement to start, then look into the CPEPâÂÂs Online Fusion Course. The Student and Teacher Resources section is another great facet of the site, featuring online and offline education resources for undergraduate and graduate students as well as teachers and scientists. Readers of all levels will walk away with well-rounded insight into the fascinating world of fusion.

403

Physics of Dust in Magnetic Fusion Devices  

NASA Astrophysics Data System (ADS)

Significant amount of dust will be produced in the next generation magnetic fusion devices due to plasma-wall interactions. The dust inventory must be controlled as it can pose a safety hazard and degrade performance. Safety concerns are due to tritium retention, dust radioactivity, toxicity, and flammability. Performance concerns include high-Z impurities carried by dust to the fusion core that can reduce plasma temperature and may even induce sudden termination of the plasma. Questions regarding dust in magnetic fusion devices therefore may be divided into dust safety, dust production, dust motion (dynamics), characteristics of dust, dust-plasma interactions, and most important of all, can dust be controlled in ways so that it will not become a severe problem for magnetic fusion energy production? The answer is not apparent at this time, which has motivated this work. Although dust safety and dust chemistry are important, our discussions primarily focus on dust physics. We describe theoretical frameworks, mostly due to dust research under a nonfusion context, that have already been established and can be used to answer many dust-related questions. We also describe dust measurements in fusion devices, numerical methods and results, and laboratory experiments related to the physics of fusion dust. Although qualitative understanding of dust in fusion has been or can be achieved, quantitative understanding of most dust physics in magnetic fusion is still needed. In order to find an effective way to deal with dust, future research activities include better dust diagnosis and monitoring, basic dusty plasma experiments emulating fusion conditions (for example, by using a mockup facility), numerical simulations bench-marked by experimental data, and development of a new generation of wall materials for fusion, which may include wall materials with engineered nanostructures.

Wang, Zhehui; Skinner, Charles H.; Luca Delzanno, Gian; Krasheninnikov, Sergei I.; Lapenta, Gianni M.; Pigarov, Alexander Yu.; Shukla, Padma K.; Smirnov, Roman D.; Ticos, Catalin M.; West, W. Phil

2008-03-01

404

Comparative analysis of fusion models based on remote sensing applications  

NASA Astrophysics Data System (ADS)

The evaluation of performances of fusion methods is a key problem in remote sensing image fusion. In this paper, four representative fusion methods, PCA fusion, WT fusion, CT fusion and TLS-GIF-WC, are adopted to fuse two sets of ALI images for comparison. The fusion products are applied to two remote sensing applications, vegetation index extraction and image classification. The normalized difference vegetation index (NDVI), vegetation coverage and classification accuracy indices are adopted to compare the fusion products. Experiments show that the GIF fusion products are more adaptive for vegetation application, since the NDVI and vegetation coverage extracted from the fusion product are consistent with that extracted from the initial image, and the ARSIS concept fusion and TLS-GIF-WC products are more adaptive for image classification, because of the higher classification accuracy.

Zhang, Ying; He, Binbin; Li, Xiaowen

2009-10-01

405

INITIAL SIZE AND DYNAMICS OF VIRAL FUSION PORES ARE A FUNCTION OF THE FUSION PROTEIN MEDIATING MEMBRANE FUSION  

PubMed Central

To investigate the role of the fusogenic protein in the initial size and dynamics of the pore that widens to finalize membrane fusion, two different fusion proteins expressed in the same cell line were investigated: the major glycoprotein of baculovirus Autographa californica (GP64) and the hemaggluttinin of influenza X31 (HA). The host Sf9 cells expressing these viral proteins, irrespective of protein species, fused to human red blood cells (RBC) upon acidification of the medium. High time resolution electrophysiological study of fusion pore conductance revealed fundamental differences in a) the initial pore conductance (pores created by HA were smaller than those created by GP64), b) the ability of pores to flicker (only HA-mediated pores flickered), and c) the time required for pore formation (HA-mediated pores took much longer to form following acidification). Thus 1) HA and GP64 have divergent electrophysiological phenotypes even when they fuse identical membranes, and 2) fusion proteins play a crucial role in determining initial fusion pore characteristics. The structure of the initial fusion pore detected by electrical conductance measurements is sensitive to the nature of the fusion protein. PMID:18208404

Plonsky, I.; Kingsley, D. H.; Rashtian, A.; Blank, P.S.; Zimmerberg, J.

2013-01-01

406

Effects on inadvertent endplate fracture following lateral cage placement on range of motion and indirect spine decompression in lumbar spine fusion constructs: A cadaveric study  

PubMed Central

Background The lateral transpsoas approach to interbody fusion is gaining popularity. Existing literature suggests that perioperative vertebra-related complications include endplate breach owing to aggressive enedplate preparation and poor bone quality. The acute effects of cage subsidence on stabilization and indirect decompression at the affected level are unknown. The purpose of this study was to compare the kinematics and radiographic metrics of indirect decompression in lumbar spines instrumented with laterally placed cages in the presence of inadvertent endplate fracture, which was determined radiographically, to specimens instrumented with lateral cages with intact endplates. Methods Five levels in 5 specimens sustained endplate fracture during lateral cage implantation followed by supplementary fixation (pedicle screw/rod [PSR]: n = 1; anterolateral plate [ALP]: n = 4), as part of a larger laboratory-based study. Range of motion (ROM) in these specimens was compared with 13 instrumented specimens with intact endplates. All specimens were scanned using computed tomography (CT) in the intact, noninstrumented condition and after 2-level cage placement with internal fixation under a 400-N follower load. Changes in disc height, foraminal area, and canal area were measured and compared between specimens with intact endplates and fractured endplates. Results Subsidence in the single PSR specimen and 4 ALP specimens was 6.5 mm and 4.3 ± 2.7 mm (range: 2.2–8.3 mm), respectively. ROM was increased in the PSR and ALP specimens with endplate fracture when compared with instrumented specimens with intact endplates. In 3 ALP specimens with endplate fracture, ROM in some motion planes increased relative to the intact, noninstrumented spine. These increases in ROM were paralleled by increase in cage translations during cyclic loading (up to 3.3 mm) and an unpredictable radiographic outcome with increases or decreases in posterior disc height, foraminal area, and canal area when compared with instrumented specimens with intact endplates. Conclusions Endplate fracture and cage subsidence noted radiographically intraoperatively or in the early postoperative period may be indicative of biomechanical instability at the affected level concomitant with a lack of neurologic decompression, which may require revision surgery.

Santoni, Brandon G.; Alexander, Gerald E.; Nayak, Aniruddh; Cabezas, Andres; Marulanda, German A.; Murtagh, Ryan; Castellvi, Antonio E.

2013-01-01

407

Inertial fusion with the LMJ  

NASA Astrophysics Data System (ADS)

The progress of the construction of very large laser facilities LMJ and NIF enables the prediction of inertial fusion achievement. These facilities will open new fields for research: the high energy density physics. Pressures of several 100 Mbars and temperatures of several 100 eV will be reached. Measurements of material properties (EOS and opacities) which have been demonstrated on current or former facilities will be possible at these never reached conditions. Pure hydrodynamics (instabilities) and radiative hydrodynamics astrophysical issues will be addressed. However, ignition and gain as a first proof of Inertial Confinement Fusion is a primary goal. The indirect drive route to inertial fusion has been prepared for many years by CEA (Commissariat ŕ l'Energie Atomique). The last ten years were imprinted by a close collaboration between CEA and US-DOE in both the areas of facilities R&D and ignition target physics. The scientific issues are well known: the propagation of laser light through the very long plasma created inside the hohlraum has to be understood and mastered to be sure that less than 10% of laser energy will be backscattered by parametric instabilities. On the other hand, the stability of the capsule implosion has to be matched with the fabrication surface finish so as to avoid shell destruction and extinction of the central hot spot. Recent advances at CEA have allowed a better confidence of reaching ignition using the facility previously specified. These works used the CEA computing capability combined with plasma experiments on existing lasers facilities. Ignition achievement also supposes the realization of suitable cryogenic targets. CEA began the construction of the Laser Megajoule (LMJ), a 240-beam laser facility, at the CEA Laboratory CESTA near Bordeaux. The LMJ is designed to deliver 2 MJ of 0.35 µm light to targets for high energy density physics experiments. Four beams were operated for plasma experiments on the Ligne d'Integration Laser (LIL) at CESTA, for the end of 2004, meeting the specifications for LMJ. The realization phase of the LMJ facility was initiated in March 2003 with the start of construction of the building and the target chamber.

Cavailler, C.

2005-12-01

408

An evaluation of fusion algorithms using image fusion metrics and human identification performance  

NASA Astrophysics Data System (ADS)

The performance of image fusion algorithms is evaluated using image fusion quality metrics and observer performance in identification perception experiments. Image Intensified (I2) and LWIR images are used as the inputs to the fusion algorithms. The test subjects are tasked to identify potentially threatening handheld objects in both the original and fused images. The metrics used for evaluation are mutual information (MI), fusion quality index (FQI), weighted fusion quality index (WFQI), and edge-dependent fusion quality index (EDFQI). Some of the fusion algorithms under consideration are based on Peter Burt's Laplacian Pyramid, Toet's Ratio of Low Pass (RoLP or contrast ratio), and Waxman's Opponent Processing. Also considered in this paper are pixel averaging, superposition, multi-scale decomposition, and shift invariant discrete wavelet transform (SIDWT). The fusion algorithms are compared using human performance in an object-identification perception experiment. The observer responses are then compared to the image fusion quality metrics to determine the amount of correlation, if any. The results of the perception test indicated that the opponent processing and ratio of contrast algorithms yielded the greatest observer performance on average. Task difficulty (V 50) associated with the I2 and LWIR imagery for each fusion algorithm is also reported.

Howell, Chris; Moore, Richard; Burks, Stephen; Halford, Carl

2007-04-01

409

In vitro fusion of Acanthamoeba phagolysosomes. I. Demonstration and quantitation of vacuole fusion in Acanthamoeba homogenates  

PubMed Central

Fusion of phagolysosomes (PLs) has been demonstrated to occur in vitro. Two separate cell homogenates of the ameba Acanthamoeba sp. (Neff) were prepared, each rich in PLs labeled with distinctive particulate markers. Portions of each were incubated together in vitro and fusion occurred as evidenced by the appearance of PLs containing both types of markers. Fusion was confirmed by electron microscopy, including serial sectioning. The membranes of fused vacuoles excluded the dye eosin Y. Surviving cells in the homogenates were not responsible for the observed fusion. Fusion was obtained using either synthetic markers (polystyrene and polyvinyltoluene latex) or biological markers (autoclaved yeast cells and glutaraldehyde-fixed goat red blood cells), or a combination of both. The specificity of PL fusion in vivo appeared to be maintained in vitro. As determined by light and electron microscopy, the fusion reaction was dependent on time and temperature, and on the initial presence of membrane around both marker particles. A minimum of 10% of the vacuoles fused by 10 min of incubation at 30 degrees C, and no rupture of the vacuoles was detected during this time. After 10 min of incubation, vacuole rupture began and fusion ceased. At a constant initial vacuole concentration, the extent of PL fusion in vitro was quantitatively reproducible. This appears to be a promising system for further investigation of membrane fusion in the lysosomal system. PMID:1245550

1976-01-01

410

Synaptotagmin-7 links fusion-activated Ca2+ entry and fusion pore dilation  

PubMed Central

ABSTRACT Ca2+-dependent regulation of fusion pore dilation and closure is a key mechanism determining the output of cellular secretion. We have recently described ‘fusion-activated’ Ca2+ entry (FACE) following exocytosis of lamellar bodies in alveolar type II cells. FACE regulates fusion pore expansion and facilitates secretion. However, the mechanisms linking this locally restricted Ca2+ signal and fusion pore expansion were still elusive. Here, we demonstrate that synaptotagmin-7 (Syt7) is expressed on lamellar bodies and links FACE and fusion pore dilation. We directly assessed dynamic changes in fusion pore diameters by analysing diffusion of fluorophores across fusion pores. Expressing wild-type Syt7 or a mutant Syt7 with impaired Ca2+-binding to the C2 domains revealed that binding of Ca2+ to the C2A domain facilitates FACE-induced pore dilation, probably by inhibiting translocation of complexin-2 to fused vesicles. However, the C2A domain hampered Ca2+-dependent exocytosis of lamellar bodies. These findings support the hypothesis that Syt7 modulates fusion pore expansion in large secretory organelles and extend our picture that lamellar bodies contain the necessary molecular inventory to facilitate secretion during the exocytic post-fusion phase. Moreover, regulating Syt7 levels on lamellar bodies appears to be essential in order that exocytosis is not impeded during the pre-fusion phase. PMID:25344253

Neuland, Kathrin; Sharma, Neeti; Frick, Manfred

2014-01-01

411

Establishment of an Institute for Fusion Studies  

SciTech Connect

The Institute for Fusion Studies is a national center for theoretical fusion plasma physics research. Its purposes are: (1) to conduct research on theoretical questions concerning the achievement of controlled fusion energy by means of magnetic confinement--including both fundamental problems of long-range significance, as well as shorter-term issues; (2) to serve as a center for information exchange, nationally and internationally, by hosting exchange visits, conferences, and workshops; (3) and to train students and postdoctoral research personnel for the fusion energy program and plasma physics research areas. The theoretical research results that are obtained by the Institute contribute mainly to the progress of national and international efforts in nuclear fusion research, whose goal is the development of fusion power.as a basic energy source. In addition to its primary focus on fusion physics, the Institute is also involved with research in related fields, such as advanced computing techniques, nonlinear dynamics, plasma astrophysics, and accelerator physics. The work of EFS scientists continued to receive national and international recognition. Numerous invited papers were given during the past year at workshops, conferences, and scientific meetings. Last year IFS scientists published 95 scientific articles in technical journals and monographs.

Hazeltine, R.D.

1992-07-01

412

Telomere fusions in early human breast carcinoma  

PubMed Central

Several lines of evidence suggest that defects in telomere maintenance play a significant role in the initiation of genomic instability during carcinogenesis. Although the general concept of defective telomere maintenance initiating genomic instability has been acknowledged, there remains a critical gap in the direct evidence of telomere dysfunction in human solid tumors. To address this topic, we devised a multiplex PCR-based assay, termed TAR (telomere-associated repeat) fusion PCR, to detect and analyze chromosome end-to-end associations (telomere fusions) within human breast tumor tissue. Using TAR fusion PCR, we found that human breast lesions, but not normal breast tissues from healthy volunteers, contained telomere fusions. Telomere fusions were detected at similar frequencies during early ductal carcinoma in situ and in the later invasive ductal carcinoma stage. Our results provide direct evidence that telomere fusions are present in human breast tumor tissue and suggest that telomere dysfunction may be an important component of the genomic instability observed in this cancer. Development of this robust method that allows identification of these genetic aberrations (telomere fusions) is anticipated to be a valuable tool for dissecting mechanisms of telomere dysfunction. PMID:22891313

Tanaka, Hiromi; Abe, Satoshi; Huda, Nazmul; Tu, LiRen; Beam, Matthew J.; Grimes, Brenda; Gilley, David

2012-01-01

413

Statistical label fusion with hierarchical performance models  

PubMed Central

Label fusion is a critical step in many image segmentation frameworks (e.g., multi-atlas segmentation) as it provides a mechanism for generalizing a collection of labeled examples into a single estimate of the underlying segmentation. In the multi-label case, typical label fusion algorithms treat all labels equally – fully neglecting the known, yet complex, anatomical relationships exhibited in the data. To address this problem, we propose a generalized statistical fusion framework using hierarchical models of rater performance. Building on the seminal work in statistical fusion, we reformulate the traditional rater performance model from a multi-tiered hierarchical perspective. This new approach provides a natural framework for leveraging known anatomical relationships and accurately modeling the types of errors that raters (or atlases) make within a hierarchically consistent formulation. Herein, we describe several contributions. First, we derive a theoretical advancement to the statistical fusion framework that enables the simultaneous estimation of multiple (hierarchical) performance models within the statistical fusion context. Second, we demonstrate that the proposed hierarchical formulation is highly amenable to the state-of-the-art advancements that have been made to the statistical fusion framework. Lastly, in an empirical whole-brain segmentation task we demonstrate substantial qualitative and significant quantitative improvement in overall segmentation accuracy. PMID:24817809

Asman, Andrew J.; Dagley, Alexander S.; Landman, Bennett A.

2014-01-01

414

Engineering Challenges in Antiproton Triggered Fusion Propulsion  

SciTech Connect

During the last decade antiproton triggered fusion propulsion has been investigated as a method for achieving high specific impulse, high thrust in a nuclear pulse propulsion system. In general the antiprotons are injected into a pellet containing fusion fuel with a small amount of fissionable material (i.e., an amount less than the critical mass) where the products from the fission are then used to trigger a fusion reaction. Initial calculations and simulations indicate that if magnetically insulated inertial confinement fusion is used that the pellets should result in a specific impulse of between 100,000 and 300,000 seconds at high thrust. The engineering challenges associated with this propulsion system are significant. For example, the antiprotons must be precisely focused. The pellet must be designed to contain the fission and initial fusion products and this will require strong magnetic fields. The fusion fuel must be contained for a sufficiently long time to effectively release the fusion energy, and the payload must be shielded from the radiation, especially the excess neutrons emitted, in addition to many other particles. We will review the recent progress, possible engineering solutions and the potential performance of these systems.

Cassenti, Brice [Department. of Engineering and Science, Rensselaer Polytechnic Institute, 275 Windsor Avenue, Hattford, CT 06120 (United States); Kammash, Terry [Nuclear Engineering Department, University of Michigan, Ann Arbor, MI 48109 (United States)

2008-01-21

415

Fusion-breeder-reactor design studies  

SciTech Connect

Studies of the technical and economic feasibility of producing fissile fuel in tandem mirrors and in tokamaks for use in fission reactors are presented. Fission-suppressed fusion breeders promise unusually good safety features and can provide make-up fuel for 11 to 18 LWRs of equal nuclear power depending on the fuel cycle. The increased revenues from sales of both electricity and fissile material might allow the commercial application of fusion technology significantly earlier than would be possible with electricity production from fusion alone. Fast-fission designs might allow a fusion reactor with a smaller fusion power and lower Q value to be economical and thus make this application of fusion even earlier. A demonstration reactor with a fusion power of 400 MW could produce 600 kg of fissile material per year at a capacity factor of 50%. The critical issues, for which small scale experiments are either being carried out or planned, are: (1) material compatibility, (2) beryllium feasibility, (3) MHD effects, and (4) pyrochemical reprocessing.

Moir, R.W.; Lee, J.D.; Coops, M.S.

1983-04-05

416

SLE and Virasoro Representations: Fusion  

NASA Astrophysics Data System (ADS)

We continue the study of null-vector equations in relation with partition functions of (systems of) Schramm-Loewner Evolutions (SLEs) by considering the question of fusion. Starting from n commuting SLEs seeded at distinct points, the partition function satisfies n null-vector equations (at level 2). We show how to obtain higher level null-vector equations by coalescing the seeds one by one. As an example, we extend Schramm's formula (for the position of a marked bulk point relatively to a chordal SLE trace) to an arbitrary number of SLE strands. The argument combines input from representation theory—the study of Verma modules for the Virasoro algebra—with regularity estimates, themselves based on hypoellipticity and stochastic flow arguments.

Dubédat, Julien

2015-01-01

417

Sensor fusion for robot navigation  

SciTech Connect

This paper demonstrates how a relatively simple vision analysis algorithm can be used in conjunction with sonar sensors to greatly improve the ability of the robot to perceive and accurately locate obstacles. So far, the system can only handle somewhat constrained environments: tall, rectangular, darker colored obstacles with well lighted, ligher colored walls forming the background. The intent was to demonstrate how a simple sensor fusion system can lead to great improvements in robot perception. The program is executed much more quickly than other more sophisticated 3D vision techniques. It is more reliable than if just one type of sensor was used. In addition, the robot, HERMIES-II, is capable of accurately maintaining its position and orientation in the navigation area. The navigation program is relatively inexpensive to implement, and is goal oriented. It allows relatively optimum paths to be found in a previously unexplored, potentially dynamic environment. 9 refs., 6 figs.

Jollay, D.M.; Ricks, R.E.

1988-01-01

418

Ion Rings for Magnetic Fusion  

SciTech Connect

This Final Technical Report presents the results of the program, Ion Rings for Magnetic Fusion, which was carried out under Department of Energy funding during the period August, 1993 to January, 2005. The central objective of the program was to study the properties of field-reversed configurations formed by ion rings. In order to reach this objective, our experimental program, called the Field-reversed Ion Ring Experiment, FIREX, undertook to develop an efficient, economical technology for the production of field-reversed ion rings. A field-reversed configuration (FRC) in which the azimuthal (field-reversing) current is carried by ions with gyro-radius comparable to the magnetic separatrix radius is called a field-reversed ion ring. A background plasma is required for charge neutralization of the ring, and this plasma will be confined within the ring's closed magnetic flux. Ion rings have long been of interest as the basis of compact magnetic fusion reactors, as the basis for a high-power accelerator for an inertial fusion driver, and for other applications of high power ion beams or plasmas of high energy density. Specifically, the FIREX program was intended to address the longstanding question of the contribution of large-orbit ions to the observed stability of experimental FRCs to the MHD tilt mode. Typical experimental FRCs with s {approx} 2-4, where s is the ratio of separatrix radius to ion gyro-radius, have been stable to tilting, but desired values for a fusion reactor, s > 20, should be unstable. The FIREX ring would consist of a plasma with large s for the background ions, but with s {approx} 1 for the ring ions. By varying the proportions of these two populations, the minimum proportion of large-orbit ions necessary for stability could be determined. The incorporation of large-orbit ions, perhaps by neutral-beam injection, into an FRC has been advanced for the purpose of stabilizing, heating, controlling angular momentum, and aiding the formation of a reactor-scale FRC, and the FIREX program was intended to test the ideas behind this approach. We will describe in this report the technological development path and advances in physics understanding that allowed FIREX to reach a regime in which ion rings were reproducibly created with up to about half the current necessary to produce field reversal. Unfortunately, the experiments were limited to this level by a fundamental, unanticipated aspect of the physics of strong ion rings in plasma. The FIREX ring is a strongly anisotropic, current-carrying population of ions moving faster than the Alfven speed in the background plasma. The rapidly changing ring current excites very large-amplitude Alfven waves in the plasma, and these waves strongly affect the ring, causing rapid energy loss in a way that is not compatible with the success of the ring trapping scenario around which FIREX was designed. The result was that FIREX rings were always very short-lived. We will discuss the implication of these results for possible future use of large-orbit ions in FRCs. In short, it appears that a certain range of the parameters characterizing the ring Alfven mach number and distribution function must be avoided to allow the existence of a long-lived energetic ion component in an FRC. This report will explain why FIREX experimental results cannot be directly scaled to quantitatively predict this range for a particular FRC configuration. This will require accurate, three-dimensional simulations. FIREX results do constitute a very good dataset for validating such a code, and simulations already carried out during this program provide a guide to the important physics involved.

Greenly, John, B.

2005-07-31

419

Vanadium recycling for fusion reactors  

SciTech Connect

Very stringent purity specifications must be applied to low activation vanadium alloys, in order to meet recycling goals requiring low residual dose rates after 50--100 years. Methods of vanadium production and purification which might meet these limits are described. Following a suitable cooling period after their use, the vanadium alloy components can be melted in a controlled atmosphere to remove volatile radioisotopes. The aim of the melting and decontamination process will be the achievement of dose rates low enough for ``hands-on`` refabrication of new reactor components from the reclaimed metal. The processes required to permit hands-on recycling appear to be technically feasible, and demonstration experiments are recommended. Background information relevant to the use of vanadium alloys in fusion reactors, including health hazards, resources, and economics, is provided.

Dolan, T.J.; Butterworth, G.J.

1994-04-01

420

Prospects of inertial confinement fusion  

NASA Astrophysics Data System (ADS)

The present status of inertial confinement fusion (ICF) is briefly reviewed, emphasizing the National Ignition Facility (NIF) project in the US and the Megajoule project in France. Critical aspects of target performance such as symmetry and stability of capsule implosions and interaction physics in hohlraum targets are discussed. The advantages of heavy-ion beam drivers and corresponding research programs are pointed out with reference to the long-term prospects for ICF power production. The new concept of the fast ignition of precompressed fuel by petawatt, picosecond laser pulses is also covered. The laser plasma group at the Max-Planck-Institute for Quantum Optics (MPQ) is one of the European institutes funded by EURATOM for an ICF keep-in-touch activity, and we highlight results obtained at MPQ relevant to the recent progress of ICF.

Meyer-ter-Vehn, J.

1997-12-01

421

Multishell inertial confinement fusion target  

DOEpatents

A method of fabricating multishell fuel targets for inertial confinement fusion usage. Sacrificial hemispherical molds encapsulate a concentric fuel pellet which is positioned by fiber nets stretched tautly across each hemispherical mold section. The fiber ends of the net protrude outwardly beyond the mold surfaces. The joint between the sacrificial hemispheres is smoothed. A ceramic or glass cover is then deposited about the finished mold surfaces to produce an inner spherical surface having continuously smooth surface configuration. The sacrificial mold is removed by gaseous reaction accomplished through the porous ceramic cover prior to enclosing of the outer sphere by addition of an outer coating. The multishell target comprises the inner fuel pellet concentrically arranged within a surrounding coated cover or shell by fiber nets imbedded within the cover material.

Holland, James R. (Butler, PA); Del Vecchio, Robert M. (Vandergrift, PA)

1984-01-01

422

Multishell inertial confinement fusion target  

DOEpatents

A method of fabricating multishell fuel targets for inertial confinement fusion usage. Sacrificial hemispherical molds encapsulate a concentric fuel pellet which is positioned by fiber nets stretched tautly across each hemispherical mold section. The fiber ends of the net protrude outwardly beyond the mold surfaces. The joint between the sacrificial hemispheres is smoothed. A ceramic or glass cover is then deposited about the finished mold surfaces to produce an inner spherical surface having continuously smooth surface configuration. The sacrificial mold is removed by gaseous reactions accomplished through the porous ceramic cover prior to enclosing of the outer sphere by addition of an outer coating. The multishell target comprises the inner fuel pellet concentrically arranged within a surrounding coated cover or shell by fiber nets imbedded within the cover material.

Holland, James R. (Butler, PA); Del Vecchio, Robert M. (Vandergrift, PA)

1987-01-01

423

Visualize Your Data with Google Fusion Tables  

NASA Astrophysics Data System (ADS)

Google Fusion Tables is a modern data management platform that makes it easy to host, manage, collaborate on, visualize, and publish tabular data online. Fusion Tables allows users to upload their own data to the Google cloud, which they can then use to create compelling and interactive visualizations with the data. Users can view data on a Google Map, plot data in a line chart, or display data along a timeline. Users can share these visualizations with others to explore and discover interesting trends about various types of data, including scientific data such as invasive species or global trends in disease. Fusion Tables has been used by many organizations to visualize a variety of scientific data. One example is the California Redistricting Map created by the LA Times: http://goo.gl/gwZt5 The Pacific Institute and Circle of Blue have used Fusion Tables to map the quality of water around the world: http://goo.gl/T4SX8 The World Resources Institute mapped the threat level of coral reefs using Fusion Tables: http://goo.gl/cdqe8 What attendees will learn in this session: This session will cover all the steps necessary to use Fusion Tables to create a variety of interactive visualizations. Attendees will begin by learning about the various options for uploading data into Fusion Tables, including Shapefile, KML file, and CSV file import. Attendees will then learn how to use Fusion Tables to manage their data by merging it with other data and controlling the permissions of the data. Finally, the session will cover how to create a customized visualization from the data, and share that visualization with others using both Fusion Tables and the Google Maps API.

Brisbin, K. E.

2011-12-01

424

Fusion Technology at CIEMAT Overview of Material Irradiation Activities  

E-print Network

Fusion Technology at CIEMAT Overview of Material Irradiation Activities A. Ibarra Ra (ENERGY, FUSION, ENVIRONMENT, TECHNOLOGY, and BASIC RESEARCH) and 3 transversal departments. #12;Ra confinement fusion as a future energy resource and coordinates the Spanish fusion research carried out as part

McDonald, Kirk

425

Fusion Frames and Robust Dimension Reduction Ali Pezeshki  

E-print Network

Fusion Frames and Robust Dimension Reduction Ali Pezeshki Princeton University Princeton, NJ 08544 fusion frame measurements in presence noise and subspace erasures. Each fusion frame mea- surement is a low-dimensional vector whose elements are inner products of an orthogonal basis for a fusion frame

Kutyniok, Gitta

426

2002 Fusion Summer Study Subgroup E4 -Development Pathway Subgroup  

E-print Network

2002 Fusion Summer Study Subgroup E4 - Development Pathway Subgroup Draft by: Farrokh Najmabadi A burning plasma experiment is a key step in developing fusion. The realization of fusion, however, requires and fusion power technologies, etc. An important discriminator among various embodiments of burning plasma

Najmabadi, Farrokh

427

FUSION OF ADE LATTICE MODELS Yu-kui Zhou1  

E-print Network

FUSION OF A­D­E LATTICE MODELS Yu-kui Zhou1 and Paul A. Pearce2 Mathematics Department, University of Melbourne, Parkville, Victoria 3052, Australia Abstract Fusion hierarchies of A­D­E face models fusion yields the face weights of both the Ising model and 3-state CSOS models. 1 Introduction The fusion

Pearce, Paul A.

428

Overview of Research and Development Activities on Fusion  

E-print Network

(oil ton/person) GWPperperson(dollar) GWP and energy consumption (2000) Oil peak #12;Fusion reactor (,R) Energy resources problem and role of fusion (3) DEMO Commercial reactorITER Nuclear Fusion 'n and talented researchersAcademic Research Basis Reactor engineering Plasma Science Fusion Science Realization

429

www.postersession.com Inertial Electrostatic Confinement Fusion for Spacecraft  

E-print Network

of fusion reactor known as an inertial electrostatic confinement (IEC) fusion reactor. Experimental hardware Fusion reactors for space power and propulsion applications 2. Model and explore the fundamental physics improvements BACKGROUND GOALS OF THE RESEARCH MULTI-GRID IEC DEVICES EXPERIMENT DEVELOPMENT IEC fusion reactors

de Weck, Olivier L.

430

Feature Fusion Hierarchies for Gender Classification Fabien Scalzo1  

E-print Network

of a two-level hierarchy which combines feature fusion and decision fusion into a unified model fusion level is defined as a set of compound features C. Each compound feature Ci combines a subsetFeature Fusion Hierarchies for Gender Classification Fabien Scalzo1 , George Bebis2 , Mircea

Bebis, George

431

An Image Fusion Approach Based on Markov Random Fields  

Microsoft Academic Search

Markov random field (MRF) models are powerful tools to model image characteristics accurately and have been successfully applied to a large number of image processing appli- cations. This paper investigates the problem of fusion of remote sensing images, e.g., multispectral image fusion, based on MRF models and incorporates the contextual constraints via MRF mod- els into the fusion model. Fusion

Min Xu; Hao Chen; Pramod K. Varshney

2011-01-01

432

Characterization of a Structural Intermediate of Flavivirus Membrane Fusion  

Microsoft Academic Search

Viral membrane fusion proceeds through a sequence of steps that are driven by triggered conformational changes of viral envelope glycoproteins, so-called fusion proteins. Although high-resolution structural snapshots of viral fusion proteins in their prefusion and postfusion conformations are available, it has been difficult to define intermediate structures of the fusion pathway because of their transient nature. Flaviviruses possess a class

Karin Stiasny; Christian Kössl; Jean Lepault; Félix A. Rey; Franz X. Heinz

2007-01-01

433

Fusion Induced by Radioactive Ion Beams  

E-print Network

The use of radioactive beams opens a new frontier for fusion studies. The coupling to the continuum can be explored with very loosely bound nuclei. Experiments were performed with beams of nuclei at or near the proton and neutron drip-lines to measure fusion and associated reactions in the vicinity of the Coulomb barrier. In addition, the fusion yield is predicted to be enhanced in reactions involving very neutron-rich unstable nuclei. Experimental measurements were carried out to investigate if it is feasible to use such beams to produce new heavy elements. The current status of these experimental activities is given in this review.

J. F. Liang; C. Signorini

2005-04-26

434

Visualizing new dimensions in Drosophila myoblast fusion  

PubMed Central

Summary Over several years, genetic studies in the model system, Drosophila melanogastor, have uncovered genes that when mutated, lead to a block in myoblast fusion. Analyses of these gene products have suggested that Arp2/3-mediated regulation of the actin cytoskeleton is crucial to myoblast fusion in the fly. Recent advances in imaging in Drosophila embryos, both in fixed and live preparations, have led to a new appreciation of both the three-dimensional organization of the somatic mesoderm and the cell biology underlying myoblast fusion. PMID:18404690

Richardson, Brian; Beckett, Karen; Baylies, Mary

2009-01-01

435

The landscape of kinase fusions in cancer  

PubMed Central

Human cancer genomes harbour a variety of alterations leading to the deregulation of key pathways in tumour cells. The genomic characterization of tumours has uncovered numerous genes recurrently mutated, deleted or amplified, but gene fusions have not been characterized as extensively. Here we develop heuristics for reliably detecting gene fusion events in RNA-seq data and apply them to nearly 7,000 samples from The Cancer Genome Atlas. We thereby are able to discover several novel and recurrent fusions involving kinases. These findings have immediate clinical implications and expand the therapeutic options for cancer patients, as approved or exploratory drugs exist for many of these kinases. PMID:25204415

Stransky, Nicolas; Cerami, Ethan; Schalm, Stefanie; Kim, Joseph L.; Lengauer, Christoph

2014-01-01

436

Fusion utility in the Knudsen layer  

SciTech Connect

In inertial confinement fusion, the loss of fast ions from the edge of the fusing hot-spot region reduces the reactivity below its Maxwellian value. The loss of fast ions may be pronounced because of the long mean free paths of fast ions, compared with those of thermal ions. We introduce a fusion utility function to demonstrate essential features of this Knudsen layer effect, in both magnetized and unmagnetized cases. The fusion utility concept is also used to evaluate the restoring reactivity in the Knudsen layer by manipulating fast ions in phase space using waves.

Davidovits, Seth; Fisch, Nathaniel J. [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08544 (United States)

2014-09-15

437

The dengue virus type 2 envelope protein fusion peptide is essential for membrane fusion  

SciTech Connect

The flaviviral envelope (E) protein directs virus-mediated membrane fusion. To investigate membrane fusion as a requirement for virus growth, we introduced 27 unique mutations into the fusion peptide of an infectious cDNA clone of dengue 2 virus and recovered seven stable mutant viruses. The fusion efficiency of the mutants was impaired, demonstrating for the first time the requirement for specific FP AAs in optimal fusion. Mutant viruses exhibited different growth kinetics and/or genetic stabilities in different cell types and adult mosquitoes. Virus particles could be recovered following RNA transfection of cells with four lethal mutants; however, recovered viruses could not re-infect cells. These viruses could enter cells, but internalized virus appeared to be retained in endosomal compartments of infected cells, thus suggesting a fusion blockade. Mutations of the FP also resulted in reduced virus reactivity with flavivirus group-reactive antibodies, confirming earlier reports using virus-like particles.

Huang, Claire Y.-H., E-mail: CHuang1@cdc.go [Division of Vector-Borne Infectious Diseases, Centers for Disease Control and Prevention, Public Health Service, U.S. Department of Health and Human Services, 3150 Rampart Rd., Fort Collins, CO 80521 (United States); Butrapet, Siritorn; Moss, Kelly J.; Childers, Thomas [Division of Vector-Borne Infectious Diseases, Centers for Disease Control and Prevention, Public Health Service, U.S. Department of Health and Human Services, 3150 Rampart Rd., Fort Collins, CO 80521 (United States); Erb, Steven M. [Arthropod-borne and Infectious Diseases Laboratory, Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO 80523 (United States); Calvert, Amanda E.; Silengo, Shawn J.; Kinney, Richard M. [Division of Vector-Borne Infectious Diseases, Centers for Disease Control and Prevention, Public Health Service, U.S. Department of Health and Human Services, 3150 Rampart Rd., Fort Collins, CO 80521 (United States); Blair, Carol D. [Arthropod-borne and Infectious Diseases Laboratory, Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO 80523 (United States); Roehrig, John T. [Division of Vector-Borne Infectious Diseases, Centers for Disease Control and Prevention, Public Health Service, U.S. Department of Health and Human Services, 3150 Rampart Rd., Fort Collins, CO 80521 (United States)

2010-01-20

438

Tritium and workers in fusion devices-lessons learnt.  

PubMed

Fusion machines from all over the world have contributed to the knowledge accumulated in fusion science. This knowledge has been applied to design new experimental fusion machines and in particular ITER. Only two fusion devices based on magnetic confinement have used deuterium and tritium fuels to-date-the Tokamak Fusion Test Reactor, TFTR, in Princeton, USA, and JET, the European tokamak. These machines have demonstrated that the fusion reaction is achievable with these fuels, and have provided valuable lessons on radioprotection-related issues as concerns tritium and workers. Dedicated tritium installations for fusion research and development have also contributed to this knowledge base. PMID:19690360

Rodriguez-Rodrigo, Lina; Elbez-Uzan, Joelle; Alejaldre, Carlos

2009-09-01

439

A New Approach to Image Fusion Based on Cokriging  

NASA Technical Reports Server (NTRS)

We consider the image fusion problem involving remotely sensed data. We introduce cokriging as a method to perform fusion. We investigate the advantages of fusing Hyperion with ALI. The evaluation is performed by comparing the classification of the fused data with that of input images and by calculating well-chosen quantitative fusion quality metrics. We consider the Invasive Species Forecasting System (ISFS) project as our fusion application. The fusion of ALI with Hyperion data is studies using PCA and wavelet-based fusion. We then propose utilizing a geostatistical based interpolation method called cokriging as a new approach for image fusion.

Memarsadeghi, Nargess; LeMoigne, Jacqueline; Mount, David M.; Morisette, Jeffrey T.

2005-01-01

440

Alternative approaches to fusion. [reactor design and reactor physics for Tokamak fusion reactors  

NASA Technical Reports Server (NTRS)

The limitations of the Tokamak fusion reactor concept are discussed and various other fusion reactor concepts are considered that employ the containment of thermonuclear plasmas by magnetic fields (i.e., stellarators). Progress made in the containment of plasmas in toroidal devices is reported. Reactor design concepts are illustrated. The possibility of using fusion reactors as a power source in interplanetary space travel and electric power plants is briefly examined.

Roth, R. J.

1976-01-01

441

Technical Feasibility of Fusion Energy Extension of the Fusion Program and Basic  

E-print Network

for Fusion Reactor in Comparison with Fossil and Fission Power Plants 7 1.2.3 Summary of the Required Specifications for Commercial Fusion Reactor 11 1.3 Comparison with Other Power Plants 13 1.3.1 Resources 13 1.3.1.1 Resources required for Fusion Reactors 16 1.3.1.2 Energy Resources 20 1.3.2 CO2 Emissions and Sustainability

442

Comparison of two-sensor tracking methods based on state vector fusion and measurement fusion  

Microsoft Academic Search

There are two approaches to the two-sensor track-fusion problem. Bar-Shalom and Campo (1986) presented the state vector fusion method, which combines state vectors from the two sensors to form a new estimate while taking into account the correlated process noise. The measurement fusion method or data compression of Willner et al. (1976) combines the measurements from the two sensors first

J. A. Roecker; C. D. McGillem

1988-01-01

443

SUPPORT FUSION ENERGY SCIENCES IN FY 2013 HELP THE UNITED STATES REMAIN A WORLD LEADER IN FUSION RESEARCH  

E-print Network

SUPPORT FUSION ENERGY SCIENCES IN FY 2013 HELP THE UNITED STATES REMAIN A WORLD LEADER IN FUSION RESEARCH RESTORE FUNDING FOR THE DOMESTIC FUSION PROGRAM AND MAINTAIN OUR COMMITMENT TO ITER the goals of the U.S. fusion program. To realize the promise of participation in ITER, cultivate future

444

Fusion of Earth Data, Sophia Antipolis, France, 28-30 January 1998 DATA FUSION: A CONCEPTUAL APPROACH FOR AN EFFICIENT  

E-print Network

Fusion of Earth Data, Sophia Antipolis, France, 28-30 January 1998 DATA FUSION: A CONCEPTUAL Antipolis cedex, France. ABSTRACT: The need for a definition of the concept of data fusion is established. Already published definitions are discussed. A new definition of the data fusion is proposed, which allows

Paris-Sud XI, Université de

445

Journal of Fusion Energy, Vol. 15, Nos. 3/4, 1996 Report of the FESAC Inertial Fusion Energy Review Panel  

E-print Network

Journal of Fusion Energy, Vol. 15, Nos. 3/4, 1996 Report of the FESAC Inertial Fusion Energy Review Marshall Rosenbluth, H,~3 William Tang, 12 and Ernest Valeo 12 Dr. Robert W. Conn, Chair Fusion Energy on a specific recommendation made by your Committee in its report, "A Restructured Fusion Energy Sciences Pro

Abdou, Mohamed

446

D-Fusion: a Distinctive Fusion Calculus Michele Boreale1, Maria Grazia Buscemi2, and Ugo Montanari2  

E-print Network

D-Fusion: a Distinctive Fusion Calculus Michele Boreale1, Maria Grazia Buscemi2, and Ugo Montanari2 Informatica, Universit`a di Pisa, Italy. boreale@dsi.unifi.it {buscemi,ugo}@di.unipi.it Abstract. Fusion that there is no uniform fully abstract embedding of pi-calculus into Fusion. This fact motivates the introduction of a new

Parrow, Joachim

447

Fusion Technologies for Tritium-Suppressed D-D Fusion White Paper prepared for FESAC Materials Science Subcommittee  

E-print Network

1 Fusion Technologies for Tritium-Suppressed D-D Fusion White Paper prepared for FESAC Materials, Columbia University 2 Plasma Science and Fusion Center, MIT December 19, 2011 Summary The proposal for tritium-suppressed D-D fusion and the understanding of the turbulent pinch in magnetically confined plasma

448

../fusion/templates/mapguide/maroon/css/maroon_fusion.css background-image: url(../images/background.gif);  

E-print Network

../fusion/templates/mapguide/maroon/css/maroon_fusion.css body { background-image: url: #500000; ../fusion/templates/mapguide/maroon/css/maroon_fusion.css #FileMenu { background-image: urlPanelTitle { background-image: url(../images/fileMenuBackground.gif); background-color: #ad1b25; Note: it appears the .gif

Ahmad, Sajjad

449

Journal of Fusion Energy, Vol. /1, No.2, 1992 Pilot Plant: An Affordable Step Toward Fusion Power  

E-print Network

is reported on a study to define a "pilot plant" to demonstrate the production of high grade heat in a fusion of the pilot plant is to demonstrate energy production from fusion in a power plant config- urationJournal of Fusion Energy, Vol. /1, No.2, 1992 Pilot Plant: An Affordable Step Toward Fusion Power S

450

Rho GTPase activity modulates paramyxovirus fusion protein-mediated cell-cell fusion.  

PubMed

The paramyxovirus fusion protein (F) promotes fusion of the viral envelope with the plasma membrane of target cells as well as cell-cell fusion. The plasma membrane is closely associated with the actin cytoskeleton, but the role of actin dynamics in paramyxovirus F-mediated membrane fusion is unclear. We examined cell-cell fusion promoted by two different paramyxovirus F proteins in three cell types in the presence of constitutively active Rho family GTPases, major cellular coordinators of actin dynamics. Reporter gene and syncytia assays demonstrated that expression of either Rac1(V12) or Cdc42(V12) could increase cell-cell fusion promoted by the Hendra or SV5 glycoproteins, though the effect was dependent on the cell type expressing the viral glycoproteins. In contrast, RhoA(L63) decreased cell-cell fusion promoted by Hendra glycoproteins but had little affect on SV5 F-mediated fusion. Also, data suggested that GTPase activation in the viral glycoprotein-containing cell was primarily responsible for changes in fusion. Additionally, we found that activated Cdc42 promoted nuclear rearrangement in syncytia. PMID:16500690

Schowalter, Rachel M; Wurth, Mark A; Aguilar, Hector C; Lee, Benhur; Moncman, Carole L; McCann, Richard O; Dutch, Rebecca Ellis

2006-07-01

451

Paramyxovirus F1 protein has two fusion peptides: implications for the mechanism of membrane fusion.  

PubMed

Viral fusion proteins contain a highly hydrophobic segment, named the fusion peptide, which is thought to be responsible for the merging of the cellular and viral membranes. Paramyxoviruses are believed to contain a single fusion peptide at the N terminus of the F1 protein. However, here we identified an additional internal segment in the Sendai virus F1 protein (amino acids 214-226) highly homologous to the fusion peptides of HIV-1 and RSV. A synthetic peptide, which includes this region, was found to induce membrane fusion of large unilamellar vesicles, at concentrations where the known N-terminal fusion peptide is not effective. A scrambled peptide as well as several peptides from other regions of the F1 protein, which strongly bind to membranes, are not fusogenic. The functional and structural characterization of this active segment suggest that the F1 protein has an additional internal fusion peptide that could participate in the actual fusion event. The presence of homologous regions in other members of the same family suggests that the concerted action of two fusion peptides, one N-terminal and the other internal, is a general feature of paramyxoviruses. PMID:10698638

Peisajovich, S G; Samuel, O; Shai, Y

2000-03-10

452

Feasibility study on sensor data fusion for the CP-140 aircraft: fusion architecture analyses  

NASA Astrophysics Data System (ADS)

Loral Canada completed (May 1995) a Department of National Defense (DND) Chief of Research and Development (CRAD) contract, to study the feasibility of implementing a multi- sensor data fusion (MSDF) system onboard the CP-140 Aurora aircraft. This system is expected to fuse data from: (a) attributed measurement oriented sensors (ESM, IFF, etc.); (b) imaging sensors (FLIR, SAR, etc.); (c) tracking sensors (radar, acoustics, etc.); (d) data from remote platforms (data links); and (e) non-sensor data (intelligence reports, environmental data, visual sightings, encyclopedic data, etc.). Based on purely theoretical considerations a central-level fusion architecture will lead to a higher performance fusion system. However, there are a number of systems and fusion architecture issues involving fusion of such dissimilar data: (1) the currently existing sensors are not designed to provide the type of data required by a fusion system; (2) the different types (attribute, imaging, tracking, etc.) of data may require different degree of processing, before they can be used within a fusion system efficiently; (3) the data quality from different sensors, and more importantly from remote platforms via the data links must be taken into account before fusing; and (4) the non-sensor data may impose specific requirements on the fusion architecture (e.g. variable weight/priority for the data from different sensors). This paper presents the analyses performed for the selection of the fusion architecture for the enhanced sensor suite planned for the CP-140 aircraft in the context of the mission requirements and environmental conditions.

Shahbazian, Elisa

1995-09-01

453

Fusion of Visual and Thermal Signatures with Eyeglass Removal for Robust Face Recognition  

Microsoft Academic Search

This paper describes a fusion of visual and thermal infrared (IR) images for robust face recognition. Two types of fusion methods are discussed: data fusion and decision fusion. Data fusion produces an illumination-invariant face image by adaptively integrating registered visual and thermal face images. Decision fusion combines matching scores of individual face recognition modules. In the data fusion process, eyeglasses,

Jingu Heo; Seong G. Kong; Besma R. Abidi; Mongi A. Abidi

2004-01-01

454

A Disparity Gradient Limit for Binocular Fusion  

Microsoft Academic Search

Ever since Panum, it has been commonly assumed that there is an absolute disparity limit for binocular fusion. It is now found that nearby objects modify this disparity limit. This result sheds new light on several enigmatic phenomena in stereopsis.

Peter Burt; Bela Julesz

1980-01-01

455

Quantum Fusion of Domain Walls with Fluxes  

E-print Network

We study how fluxes on the domain wall world volume modify quantum fusion of two distant parallel domain walls into a composite wall. The elementary wall fluxes can be separated into parallel and antiparallel components. The parallel component affects neither the binding energy nor the process of quantum merger. The antiparallel fluxes, instead, increase the binding energy and, against naive expectations, suppress quantum fusion. In the small flux limit we explicitly find the bounce solution and the fusion rate as a function of the flux. We argue that at large (antiparallel) fluxes there exists a critical value of the flux (versus the difference in the wall tensions), which switches off quantum fusion altogether. This phenomenon of flux-related wall stabilization is rather peculiar: it is unrelated to any conserved quantity. Our consideration of the flux-related all stabilization is based on substantiated arguments that fall short of complete proof.

S. Bolognesi; M. Shifman; M. B. Voloshin

2009-07-20

456

Microscopic study of Ca$+$Ca fusion  

E-print Network

We investigate the fusion barriers for reactions involving Ca isotopes $\\mathrm{^{40}Ca}+\\mathrm{^{40}Ca}$, $\\mathrm{^{40}Ca}+\\mathrm{^{48}Ca}$, and $\\mathrm{^{48}Ca}+\\mathrm{^{48}Ca}$ using the microscopic time-dependent Hartree-Fock theory coupled with a density constraint. In this formalism the fusion barriers are directly obtained from TDHF dynamics. We also study the excitation of the pre-equilibrium GDR for the $\\mathrm{^{40}Ca}+\\mathrm{^{48}Ca}$ system and the associated $\\gamma$-ray emission spectrum. Fusion cross-sections are calculated using the incoming-wave boundary condition approach. We examine the dependence of fusion barriers on collision energy as well as on the different parametrizations of the Skyrme interaction.

R. Keser; A. S. Umar; V. E. Oberacker

2012-02-17

457

Fusion materials modeling: Challenges and opportunities  

E-print Network

The plasma facing components, first wall, and blanket systems of future tokamak-based fusion power plants arguably represent the single greatest materials engineering challenge of all time. Indeed, the United States National ...

Wirth, B. D.

458

Alloy Design for a Fusion Power Plant  

E-print Network

Fusion power is generated when hot deuterium and tritium nuclei react, producing alpha particles and 14 MeV neutrons. These neutrons escape the reaction plasma and are absorbed by the surrounding material structure of the plant, transferring...

Kemp, Richard

459

External Factors Affecting Fusion Energy Development  

NASA Astrophysics Data System (ADS)

A number of external factors affecting the pace and direction of fusion energy development are reviewed and discussed. These include the changing electric utility marketplace environment, the availability of fossil fuels, competing power sources, and environmental issues.

Dean, Stephen O.

1999-06-01

460

External Factors Affecting Fusion Energy Development  

Microsoft Academic Search

A number of external factors affecting the pace and direction of fusion energy development are reviewed and discussed. These include the changing electric utility marketplace environment, the availability of fossil fuels, competing power sources, and environmental issues.

Stephen O. Dean

1999-01-01