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Sample records for artificial disc activ

  1. Artificial Cervical Disc Replacement Improves Mobility

    Science.gov (United States)

    Artificial Cervical Disc Replacement Improves Mobility February 18, 2009 From PinnacleHealth, Harrisburg, PA Welcome to this “OR ... this new technology with the use of an artificial disc has some significant benefits over the previous ...

  2. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... spine problems in up to date but this new technology with the use of an artificial disc ... of patients for many, many. Prior to this new technology, we would take out that disc and ...

  3. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... problems in up to date but this new technology with the use of an artificial disc has ... patients for many, many. Prior to this new technology, we would take out that disc and then ...

  4. The activArtificial Disc: a next-generation motion-preserving implant for chronic lumbar discogenic pain

    OpenAIRE

    Yue, James J.; Garcia, Rolando; Miller, Larry E.

    2016-01-01

    Degeneration of the lumbar intervertebral discs is a leading cause of chronic low back pain in adults. Treatment options for patients with chronic lumbar discogenic pain unresponsive to conservative management include total disc replacement (TDR) or lumbar fusion. Until recently, only two lumbar TDRs had been approved by the US Food and Drug Administration − the Charité Artificial Disc in 2004 and the ProDisc-L Total Disc Replacement in 2006. In June 2015, a next-generation lumbar TDR receive...

  5. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available Artificial Cervical Disc Replacement Improves Mobility February 18, 2009 From PinnacleHealth, Harrisburg, PA Welcome to this “OR ... this new technology with the use of an artificial disc has some significant benefits over the previous ...

  6. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... to date but this new technology with the use of an artificial disc has some significant benefits ... facing straight up. The incision that Dr. Beutler uses is a little over an inch long, and ...

  7. Requirements for an artificial intervertebral disc

    NARCIS (Netherlands)

    Eijkelkamp, MF; van Donkelaar, CC; Veldhuizen, AG; van Horn, [No Value; Huyghe, JM; Verkerke, GJ

    2001-01-01

    Intervertebral disc degeneration is an important social and economic problem. Presently available artificial intervertebral discs (AIDs) are insufficient and the main surgical intervention is still spinal fusion. The objective of the present study is to present a list of requirements for the develop

  8. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... plate. Obviously that procedure has worked out very well, but there’s probably a lot of really significant ... fusing this area, putting in an artificial disc. Well it allows motion, you know, and there’s been ...

  9. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... ultrahigh molecular weight polyethylene, and it’s a medical-grade plastic that’s really been made to sustain active ... the disc level above and below as well. Good point. It does, and so I’m kind ...

  10. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... over, you know, fusion. People wonder, does it cause problems at the next level up, so if ... a concern. Will the fusion at this disc cause problems at the disc above or the disc ...

  11. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... so much different than the fusion. The ProDisc C total disc replacement from Synthes Spine is an ... intervertebral disc in the cervical spine. The ProDisc C is indicated for patients suffering from intractable symptomatic ...

  12. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... a total disc replacement arthroplasty on a young patient who has a herniated disc in her neck. ... way in, it’s, you know, I find that patients have very little pain after surgery. And just ...

  13. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... to delineate the exact trajectory into the disc space. So now he’s found the disc space, what he wants to do is confirm it ... has stuck a marker into this actual disc space, and the next thing he is goes to ...

  14. The activArtificial Disc: a next-generation motion-preserving implant for chronic lumbar discogenic pain

    OpenAIRE

    Yue JJ; Garcia Jr R; Miller LE

    2016-01-01

    James J Yue,1 Rolando Garcia Jr,2 Larry E Miller3 1Department of Orthopaedic Surgery, Yale School of Medicine, New Haven, CT, 2Orthopedic Care Center, Miami, FL, 3Miller Scientific Consulting, Inc., Asheville, NC, USA Abstract: Degeneration of the lumbar intervertebral discs is a leading cause of chronic low back pain in adults. Treatment options for patients with chronic lumbar discogenic pain unresponsive to conservative management include total disc replacement (TDR) or lumbar f...

  15. The activArtificial Disc: a next-generation motion-preserving implant for chronic lumbar discogenic pain

    OpenAIRE

    Miller, Larry E.

    2016-01-01

    James J Yue,1 Rolando Garcia Jr,2 Larry E Miller3 1Department of Orthopaedic Surgery, Yale School of Medicine, New Haven, CT, 2Orthopedic Care Center, Miami, FL, 3Miller Scientific Consulting, Inc., Asheville, NC, USA Abstract: Degeneration of the lumbar intervertebral discs is a leading cause of chronic low back pain in adults. Treatment options for patients with chronic lumbar discogenic pain unresponsive to conservative management include total disc replacement (TDR) or ...

  16. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... implant components work together with the surrounding spinal structures to provide stability and function. The ProDisc C implant is secured to the vertebral bodies above and below the disc space and held in place with two central keels. ...

  17. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... put my handle back on, and meanwhile, the scrub nurse is preparing the actual disc itself because ... was doing that on the back table, the scrub nurse and the circulating nurse were putting together ...

  18. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... the location of the diseased disc, and the soft tissues are moved away from the front of the ... a zero-profile implant that does not contact soft tissue structures after it is implanted. The technical aspect ...

  19. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... wonder, does it cause problems at the next level up, so if I fuse this disc here, ... fusion, then the hope is that the next levels hopefully won’t feel the stress, and by ...

  20. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... the way to do this in the near future of the state of the art. What are ... the-art of treating disc herniations in the future. Thank you. Thank you for watching this “OR ...

  1. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... stress, and by not feeling the stress, they should maintain good discs, hopefully over the lifetime of ... right where it wants to be, and that should be a natural position for the bones of ...

  2. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... implant that is composed of two cobalt chrome alloy end plates and a polyethylene insert. The polyethylene ... the ProDisc C implant have a plasma-sprayed titanium coding to provide bony coating to promote bony ...

  3. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... place with two central keels. All bone contacting surfaces of the ProDisc C implant have a plasma-sprayed titanium coding to provide bony coating to promote bony on growth, providing long-term ...

  4. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... fascia, which is kind of connective tissue that helps hold things together. It’s the very last layer ... placing a marker external to the skin to help to delineate the exact trajectory into the disc ...

  5. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... it out, the patient’s chin is to the right and the chest wall is towards the left, and he’s dissecting up and down. So the ... other nerve, the one that goes down his left arm, and if both are freed up, we’ll put in a piece of disc where we took out our disc right through here. Can I have a nerve fork, ...

  6. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... it gets inserted, it’s very rough. It’s titanium plasma sprayed, and this allows for the body to ... surfaces of the ProDisc C implant have a plasma-sprayed titanium coding to provide bony coating to ...

  7. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... diseased disc and releasing pressure on the surrounding nerves and spinal cord. We’re going to do an image ... with that motion is going to push against nerves or the spinal cord. So it’s sometimes a little bit more ...

  8. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... is exactly where I’m putting my instruments right now, and those are small pieces of disc that I’m taking out. I’m obviously going real slow through this area, and the reason is ...

  9. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... the next levels hopefully won’t feel the stress, and by not feeling the stress, they should maintain good discs, hopefully over the ... was an appropriate procedure that would work. These studies turned out well, and the FDA has approved ...

  10. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... the next levels hopefully won’t feel the stress, and by not feeling the stress, they should maintain good discs, hopefully over the ... FDA studies, in our study, in all the literature that I’ve read has been extremely positive ...

  11. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... see it gets inserted, it’s very rough. It’s titanium plasma sprayed, and this allows for the body ... the ProDisc C implant have a plasma-sprayed titanium coding to provide bony coating to promote bony ...

  12. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... That’s the actual disc space right there. It’s beautiful. So I’m going to take a scalpel ... And that’s where I wan it. That looks beautiful, so I’m very pleased about that. I’ ...

  13. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... younger patients, the patients in their 30s and 40s with disc herniations, than an older patient, let’s ... go to the recovery room, spend maybe an hour, hour and 15 minutes in recovery room and ...

  14. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... the next levels hopefully won’t feel the stress, and by not feeling the stress, they should maintain good discs, hopefully over the ... cord. So it’s sometimes a little bit more work. Well, there’s the space for where that nerve ...

  15. Improving the fixation of an artificial intervertebral disc

    NARCIS (Netherlands)

    Eijkelkamp, MF; Hayen, J; Veldhuizen, AG; Van Horn, [No Value; Verkerke, GJ

    2002-01-01

    The fixation of an artificial intervertebral disc has been studied especially with respect to the dimensions, the convexity of the endplates and the size of the fixation elements. From literature and cadaveric vertebrae, the dimensions and shape of the lumbar vertebral endplates were determined and

  16. The Research of Artificial Cervical Disc Replacement

    Institute of Scientific and Technical Information of China (English)

    Zhao Zhua; Qiang Shenb

    2008-01-01

    Cervical arthroplasty after anterior decompression with insertion of a prosthetic total disc replacement has been suggested as an alternate to anterior cervical fusion. It develops quickly during recent years. Currently there are several cervical arthroplasty devices. Each device varies in terms of materials, range of motion and constraint. Early studies suggest that in the short term, the complication rate and efficacy is no worse than fusion surgery. Long-term results have not yet been reported. This review examines the current prostheses as well as discussing issues regarding indications and technique. It is hoped that an improvement of cervical arthroplasty occurs in terms of materials and design as spinal surgeons enter a new dines of the management of cervical spine disease.

  17. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... piece of what we call -- it’s a medical plastic. It’s ultrahigh molecular weight polyethylene, and it’s a medical-grade plastic that’s really been made to sustain active compression ...

  18. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... ultrahigh molecular weight polyethylene, and it’s a medical-grade plastic that’s really been made to sustain active ... bit. That’s just fluid to wash out any blood or bone wax or whatever, pieces of bone. ...

  19. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... guy, and he wants to go back to work, you know, within a week or so. And so we’re -- his wife ... little bit. But people are up and at work and doing activities by around two, three weeks, and people are back to doing sports like. ...

  20. Artificial Cervical Disc Replacement Improves Mobility

    Medline Plus

    Full Text Available ... molecular weight polyethylene, and it’s a medical-grade plastic that’s really been made to sustain active compression and motion on this area for many, many, many year, decades. And so you can see when the components are placed in place that the body is able to maintain motion of the neck ...

  1. Minimizing cryopreservation-induced loss of disc cell activity for storage of whole intervertebral discs

    OpenAIRE

    SCW Chan; SKL Lam; VYL Leung; Chan, D.; KDK Luk; KMC Cheung

    2010-01-01

    Severe intervertebral disc (IVD) degeneration often requires disc excision and spinal fusion, which leads to loss of spinal segment mobility. Implantation of an allograft disc or tissue engineered disc construct emerges as an alternative to artificial disc replacement for preserving the motion of the degenerated level. Establishment of a bank of cadaveric or engineered cryopreserved discs enables size matching, and facilitates clinical management. However, there is a lack of understanding of ...

  2. Frisbee - the first artificial cervical disc of 3RD generation

    OpenAIRE

    Karin Büttner-Janz; Bernhard Meyer; Rafael Donatus Sambale; Hans-Joachim Wilke; Nelli Rüdiger; Eiko Büttner

    2014-01-01

    OBJECTIVE: The current cervical disc arthroplasty is limited by postoperative facet joint arthritis, heterotopic ossification and segmental kyphosis. The total Frisbee disc, which has an upper convex/concave non-spherical surface and a lower flat sliding surface, is a new approach for improved outcomes. Prior to clinical application, safety and suitability tests are required. METHODS: The Frisbee is the first 3rd generation disc according to a new classification of total disc because it can...

  3. Preliminary results of Activ C artificial disc replacement for cervical spondylosis%Activ C人工椎间盘置换术治疗颈椎病的早期疗效

    Institute of Scientific and Technical Information of China (English)

    赵耀; 刘屹林; 王利民; 谭洪宇; 王卫东; 廖文胜; 鲍恒

    2012-01-01

    目的:观察Activ C人工椎间盘置换术治疗颈椎病的早期临床疗效,分析其临床应用价值.方法:2009年11月~2011年3月在我院接受Activ C人工椎间盘置换术并获得随访的颈椎病患者共43例(45个节段),平均年龄48.3岁,其中男18例,女25例,脊髓型颈椎病22例,神经根型颈椎病16例,混合型颈椎病5例;单节段置换41例(C3/4 2例,C4/5 17例,C5/6 21例,C6/7 1例),双节段置换2例(C4/5和C5/6 1例,C5/6和C6/7 1例).采用日本骨科协会JOA评分、颈椎活动障碍指数(NDI)和疼痛视觉模拟评分(VAS)评价术后症状改善程度,比较手术前后的颈椎曲度、手术节段及邻近上下节段活动度变化,观察统计手术并发症情况.结果:术后随访8~24个月,平均13.8个月.患者的JOA评分、NDI、颈部VAS评分、上肢VAS评分分别由术前的8.2±0.7、35.3±4.7、6.8±1.1和6.5±1.2分显著改善至末次随访时的14.7±0.4、16.2±3.4、1.3±0.8和1.8±0.9分(P均<0.05).颈椎生理曲度术前为7.97°±4.49°,末次随访时为9.15°±3.85°,手术前后无明显差异(P>0.05).置换节段活动度较术前明显增加(P<0.01),邻近上下节段活动度手术前后差异无统计学意义(P>0.05).术后人工椎间盘活动良好,无塌陷或移位,随访期间未见邻近节段明显退变,2例分别在术后7个月和10个月时异位骨化形成.结论:Activ C人工椎间盘置换术可有效改善颈椎病患者的临床症状,维持颈椎的生理曲度和活动度,早期临床疗效满意.%Objectives: To investigate the early clinical effects of cervical Activ C artificial disc replacement. Methods: 43 patients(mean age 48.3 years; 18 males and 25 females) of cervical spondylosis with a total of 45 levels involved underwent anterior cervical decompression and Activ C implantation between November 2009 and March 2011. There were 22 cases of cervical spondylotic myelopathy, 16 cases of cervical spondy-lotic radiculopathy and 5 cases of mixed

  4. Activ C cervical disc replacement for myelopathy

    Directory of Open Access Journals (Sweden)

    L McGonagle

    2011-01-01

    Full Text Available Background: Cervical disc replacement is becoming an increasingly popular treatment option for cervical myelopathy. It retains motion at the affected segment, unlike anterior cervical discectomy and fusion. The aim of this study is to assess the outcomes of a series of patients who underwent Activ C disc replacement for cervical myelopathy. Materials and Methods: A series of patients at the above Trust with clinical and radiological evidence of cervical myelopathy who were suitable for cervical disc replacement from 2007 to 2009 were included. Implants were inserted by one of two consultant surgeons {IMS, MO′M}. Patients were assessed preoperatively and at six, 12 and 24 months, postoperatively, with a visual analogue score (VAS for neck and arm pain severity and frequency, the Neck Disability Index questionnaire (NDI and the Centre for Epidemiologic Studies Depression questionnaire (CES-D. Results: Ten patients underwent surgery between May 2007 and July 2009, 6 women, and 4 men. Average age was 54 years (40-64. Disc levels replaced were: four at C4-5; eight at C5-6; seven at C6-7. Three patients had one disc replaced, five patients had two discs replaced, and two patients had three discs replaced. The VAS for neck pain improved from 5.9 pre-operatively to 1.4-24 months postoperatively and the VAS arm pain improved from 5.4 to 2.6. The NDI improved from 51% preoperatively to 26.8% at 24 months postoperatively. The CES-D showed a slight increase from 19.5 preoperatively to 21.7 at 24 months, postoperatively. Conclusion: Cervical decompression and disc replacement improves pain and function in patients with cervical myelopathy. This benefit is maintained at 24 months post op, with no cases requiring revision.

  5. Cervical disc arthroplasty with ProDisc-C artificial disc: 5-year radiographic follow-up results

    Institute of Scientific and Technical Information of China (English)

    ZHAO Yan-bin; SUN Yu; ZHOU Fei-fei; LIU ZHONG-jun

    2013-01-01

    Background Cervical disc arthroplasty is an alternative surgery to standard cervical decompression and fusion for disc degeneration.Different types of cervical disc prosthesis are used in China.The aim of this study was to evaluate the radiographic outcomes of cervical arthroplasty using the ProDisc-C prosthesis.Methods Radiographic evaluation,including static and dynamic flexion-extension lateral images,was performed at baseline and at final follow-up.Results Twenty six patients who had single-level ProDisc-C arthroplasty were followed up for a mean period of 63 months (56-76 months).The range of motion at the operated level was 9.3°±3.7° at baseline and 7.3°±3.5° at final follow-up,with a significant difference (P <0.05).Seventeen of 26 levels (65.4%) developed heterotopic ossification:three were classified as grade Ⅱ,13 were classified as grade Ⅲ,and 1 as grade Ⅳ,according to McAfee's classification.Forty nine adjacent segments were evaluated by lateral Ⅹ-ray and 18 (36.7%) segments developed adjacent segment degenerations.Conclusions ProDisc-C arthroplasty had acceptable radiographic results at 5-year follow-up.The range of motion was preserved.However,more than 60% of the patients developed heterotopic ossification.

  6. Magnetic activity in accretion disc boundary layers

    Science.gov (United States)

    Armitage, Philip J.

    2002-03-01

    We use three-dimensional magnetohydrodynamic simulations to study the structure of the boundary layer between an accretion disc and a non-rotating, unmagnetized star. Under the assumption that cooling is efficient, we obtain a narrow but highly variable transition region in which the radial velocity is only a small fraction of the sound speed. A large fraction of the energy dissipation occurs in high-density gas adjacent to the hydrostatic stellar envelope, and may therefore be reprocessed and largely hidden from view of the observer. As suggested by Pringle, the magnetic field energy in the boundary layer is strongly amplified by shear, and exceeds that in the disc by an order of magnitude. These fields may play a role in generating the magnetic activity, X-ray emission and outflows in disc systems where the accretion rate is high enough to overwhelm the stellar magnetosphere.

  7. Frisbee - the first artificial cervical disc of 3RD generation

    Directory of Open Access Journals (Sweden)

    Karin Büttner-Janz

    2014-03-01

    Full Text Available OBJECTIVE: The current cervical disc arthroplasty is limited by postoperative facet joint arthritis, heterotopic ossification and segmental kyphosis. The total Frisbee disc, which has an upper convex/concave non-spherical surface and a lower flat sliding surface, is a new approach for improved outcomes. Prior to clinical application, safety and suitability tests are required. METHODS: The Frisbee is the first 3rd generation disc according to a new classification of total disc because it can precisely mimic the segmental ROM, including the soft limitation of axial rotation. The ISO 18192-1 test was carried out to determine the rate of wear debris. A FE model was used to assess the safety of prosthetic components. In the sagittal plane several variables to determine the most favorable lordotic angle were evaluated. RESULTS: Two angled prosthetic plates are safer than one sliding angled core to prevent the displacement. The lordosis of 7° of the Frisbee leads to kyphosis of no more than 2° without reduction of the ROM. The wear rate of the Frisbee is five times smaller compared to an FDA-approved disc with a spherical sliding surface. CONCLUSIONS: Based on the test results, the clinical application of Frisbee can now be studied. The postoperative kyphosis observed with other devices is not an issue with the Frisbee design. Physiological ROM is combined with the significant reduction of wear debris. For these reasons the Frisbee has the potential to provide a better balanced segmental loading reducing the degeneration of the joint surface and heterotopic ossification.

  8. Artificial cervical disc replacement: Principles, types and techniques

    Directory of Open Access Journals (Sweden)

    Sekhon L

    2005-01-01

    Full Text Available Cervical arthroplasty after anterior decompression with insertion of a prosthetic total disc replacement has been suggested as an alternate to anterior cervical fusion. Currently there are four cervical arthroplasty devices available on the market whose results in clinical use have been reported. Each device varies in terms of materials, range of motion, insertion technique and constraint. It is not known which device is ideal. Early studies suggest that in the short term, the complication rate and efficacy is no worse than fusion surgery. Long-term results have not yet been reported. This review examines the current prostheses available on the market as well as discussing issues regarding indications and technique. Pitfalls are discussed and early experiences reviewed. In time, it is hoped that a refinement of cervical arthroplasty occurs in terms of both materials and design as well as in terms of indications and clinical outcomes as spinal surgeons enter a new era of the management of cervical spine disease.

  9. Outflows from dynamo-active protostellar accretion discs

    CERN Document Server

    Von Rekowski, B; Dobler, W; Shukurov, A M; Brandenburg, Axel; Dobler, Wolfgang; Rekowski, Brigitta von; Shukurov, Anvar

    2003-01-01

    An axisymmetric model of a cool, dynamo-active accretion disc is applied to protostellar discs. Thermally and magnetically driven outflows develop that are not collimated within 0.1 AU. In the presence of a central magnetic field from the protostar, accretion onto the protostar is highly episodic, which is in agreement with earlier work.

  10. Biomechanics of Artificial Disc Replacements Adjacent to a 2-Level Fusion in 4-Level Hybrid Constructs: An In Vitro Investigation

    OpenAIRE

    Liao, Zhenhua; Fogel, Guy R.; Wei, Na; Gu, Hongsheng; Liu, Weiqiang

    2015-01-01

    Background The ideal procedure for multilevel cervical degenerative disc diseases remains controversial. Recent studies on hybrid surgery combining anterior cervical discectomy and fusion (ACDF) and artificial cervical disc replacement (ACDR) for 2-level and 3-level constructs have been reported in the literature. The purpose of this study was to estimate the biomechanics of 3 kinds of 4-level hybrid constructs, which are more likely to be used clinically compared to 4-level arthrodesis. Mate...

  11. Planet Signatures in Collisionally Active Debris Discs: scattered light images

    CERN Document Server

    Thebault, Philippe; Ertel, Steve

    2012-01-01

    Planet perturbations are often invoked as a potential explanation for many spatial structures that have been imaged in debris discs. So far this issue has been mostly investigated with collisionless N-body numerical models. We numerically investigate how the coupled effect of collisions and radiation pressure can affect the formation and survival of radial and azimutal structures in a disc perturbed by a planet. We consider two set-ups: a planet embedded within an extended disc and a planet exterior to an inner debris ring. We use the DyCoSS code of Thebault(2012) and derive synthetic images of the system in scattered light. The planet's mass and orbit, as well as the disc's collisional activity are explored as free parameters. We find that collisions always significantly damp planet-induced structures. For the case of an embedded planet, the planet's signature, mostly a density gap around its radial position, should remain detectable in head-on images if M_planet > M_Saturn. If the system is seen edge-on, ho...

  12. Artificial disc and vertebra system: a novel motion preservation device for cervical spinal disease after vertebral corpectomy

    Directory of Open Access Journals (Sweden)

    Jun Dong

    2015-07-01

    Full Text Available OBJECTIVE: To determine the range of motion and stability of the human cadaveric cervical spine after the implantation of a novel artificial disc and vertebra system by comparing an intact group and a fusion group. METHODS: Biomechanical tests were conducted on 18 human cadaveric cervical specimens. The range of motion and the stability index range of motion were measured to study the function and stability of the artificial disc and vertebra system of the intact group compared with the fusion group. RESULTS: In all cases, the artificial disc and vertebra system maintained intervertebral motion and reestablished vertebral height at the operative level. After its implantation, there was no significant difference in the range of motion (ROM of C3-7 in all directions in the non-fusion group compared with the intact group (p>0.05, but significant differences were detected in flexion, extension and axial rotation compared with the fusion group (p<0.05. The ROM of adjacent segments (C3-4, C6-7 of the non-fusion group decreased significantly in some directions compared with the fusion group (p<0.05. Significant differences in the C4-6 ROM in some directions were detected between the non-fusion group and the intact group. In the fusion group, the C4-6 ROM in all directions decreased significantly compared with the intact and non-fusion groups (p<0.01. The stability index ROM (SI-ROM of some directions was negative in the non-fusion group, and a significant difference in SI-ROM was only found in the C4-6 segment of the non-fusion group compared with the fusion group. CONCLUSION: An artificial disc and vertebra system could restore vertebral height and preserve the dynamic function of the surgical area and could theoretically reduce the risk of adjacent segment degeneration compared with the anterior fusion procedure. However, our results should be considered with caution because of the low power of the study. The use of a larger sample should be

  13. Artificial light and nocturnal activity in gammarids

    Directory of Open Access Journals (Sweden)

    Elizabeth K. Perkin

    2014-03-01

    Full Text Available Artificial light is gaining attention as a potential stressor to aquatic ecosystems. Artificial lights located near streams increase light levels experienced by stream invertebrates and we hypothesized light would depress night drift rates. We also hypothesized that the effect of light on drift rates would decrease over time as the invertebrates acclimated to the new light level over the course of one month’s exposure. These hypotheses were tested by placing Gammarus spp. in eight, 75 m × 1 m artificial flumes. One flume was exposed to strong (416 lx artificial light at night. This strong light created a gradient between 4.19 and 0.04 lx over the neighboring six artificial flumes, while a control flume was completely covered with black plastic at night. Night-time light measurements taken in the Berlin area confirm that half the flumes were at light levels experienced by urban aquatic invertebrates. Surprisingly, no light treatment affected gammarid drift rates. In contrast, physical activity measurements of in situ individually caged G. roeseli showed they increased short-term activity levels in nights of complete darkness and decreased activity levels in brightly lit flumes. Both nocturnal and diurnal drift increased, and day drift rates were unexpectadly higher than nocturnal drift.

  14. Mechanically activated artificial cell by using microfluidics

    Science.gov (United States)

    Ho, Kenneth K. Y.; Lee, Lap Man; Liu, Allen P.

    2016-01-01

    All living organisms sense mechanical forces. Engineering mechanosensitive artificial cell through bottom-up in vitro reconstitution offers a way to understand how mixtures of macromolecules assemble and organize into a complex system that responds to forces. We use stable double emulsion droplets (aqueous/oil/aqueous) to prototype mechanosensitive artificial cells. In order to demonstrate mechanosensation in artificial cells, we develop a novel microfluidic device that is capable of trapping double emulsions into designated chambers, followed by compression and aspiration in a parallel manner. The microfluidic device is fabricated using multilayer soft lithography technology, and consists of a control layer and a deformable flow channel. Deflections of the PDMS membrane above the main microfluidic flow channels and trapping chamber array are independently regulated pneumatically by two sets of integrated microfluidic valves. We successfully compress and aspirate the double emulsions, which result in transient increase and permanent decrease in oil thickness, respectively. Finally, we demonstrate the influx of calcium ions as a response of our mechanically activated artificial cell through thinning of oil. The development of a microfluidic device to mechanically activate artificial cells creates new opportunities in force-activated synthetic biology. PMID:27610921

  15. Biomechanics of Artificial Disc Replacements Adjacent to a 2-Level Fusion in 4-Level Hybrid Constructs: An In Vitro Investigation.

    Science.gov (United States)

    Liao, Zhenhua; Fogel, Guy R; Wei, Na; Gu, Hongsheng; Liu, Weiqiang

    2015-01-01

    BACKGROUND The ideal procedure for multilevel cervical degenerative disc diseases remains controversial. Recent studies on hybrid surgery combining anterior cervical discectomy and fusion (ACDF) and artificial cervical disc replacement (ACDR) for 2-level and 3-level constructs have been reported in the literature. The purpose of this study was to estimate the biomechanics of 3 kinds of 4-level hybrid constructs, which are more likely to be used clinically compared to 4-level arthrodesis. MATERIAL AND METHODS Eighteen human cadaveric spines (C2-T1) were evaluated in different testing conditions: intact, with 3 kinds of 4-level hybrid constructs (hybrid C3-4 ACDR+C4-6 ACDF+C6-7ACDR; hybrid C3-5ACDF+C5-6ACDR+C6-7ACDR; hybrid C3-4ACDR+C4-5ACDR+C5-7ACDF); and 4-level fusion. RESULTS Four-level fusion resulted in significant decrease in the C3-C7 ROM compared with the intact spine. The 3 different 4-level hybrid treatment groups caused only slight change at the instrumented levels compared to intact except for flexion. At the adjacent levels, 4-level fusion resulted in significant increase of contribution of both upper and lower adjacent levels. However, for the 3 hybrid constructs, significant changes of motion increase far lower than 4P at adjacent levels were only noted in partial loading conditions. No destabilizing effect or hypermobility were observed in any 4-level hybrid construct. CONCLUSIONS Four-level fusion significantly eliminated motion within the construct and increased motion at the adjacent segments. For all 3 different 4-level hybrid constructs, ACDR normalized motion of the index segment and adjacent segments with no significant hypermobility. Compared with the 4-level ACDF condition, the artificial discs in 4-level hybrid constructs had biomechanical advantages compared to fusion in normalizing adjacent level motion. PMID:26694835

  16. Constraints on active galactic nucleus accretion disc viscosity derived from continuum variability

    NARCIS (Netherlands)

    R.L.C. Starling; A. Siemiginowska; P. Uttley; R. Soria

    2004-01-01

    We estimate a value of the viscosity parameter in active galactic nucleus (AGN) accretion discs for the Palomar-Green quasar sample. We assume that optical variability on time-scales of months to years is caused by local instabilities in the inner accretion disc. Comparing the observed variability t

  17. Artificial oocyte activation: evidence for clinical readiness.

    Science.gov (United States)

    Ebner, T; Montag, M

    2016-03-01

    Artificial oocyte activation using Ca(2+)ionophores or similar compounds is a widely applied technique in IVF laboratories. This is all the more interesting as most of the agents aiming for intracellular Ca(2+) increase do not result in physiological Ca(2+) oscillations but much rather cause a single Ca(2+) transient. Two observations from mammals may explain why a rather non-physiological single Ca(2+) peak caused by ionophores is sufficient to rescue cycles showing severe male factor infertility, deficient oocyte maturation, developmental problems in humans, or both. On the one hand, it has been shown that it is mainly the initial Ca(2+) rise that drives further downstream events, in particular calcium/calmodulin-dependent protein kinase II (CaMKII) action, and on the other, it is possible that this enzyme remains active even in the absence of Ca(2+). It therefore seems that mammalian oocytes can respond to a wide range of intracellular Ca(2+) signals and have a surprisingly high degree of tolerance for changes in cytosolic Ca(2+). As epigenetic consequences or differences in gene expression have not been studied to date, artificial oocyte activation has to be considered as experimental and should only be applied with a proper indication. PMID:26776820

  18. Comparison of wear behaviors for an artificial cervical disc under flexion/extension and axial rotation motions.

    Science.gov (United States)

    Wang, Song; Song, Jian; Liao, Zhenhua; Feng, Pingfa; Liu, Weiqiang

    2016-06-01

    The wear behaviors of a ball-on-socket (UHMWPE-on-Ti6Al4V) artificial cervical disc were studied with 1.5MC (million cycles) wear simulation under single flexion/extension and axial rotation motion and their composite motion. The wear rates, wear traces, and contact stress were analyzed and contrasted based on mass loss, optical microscopy and SEM as well as 3D profilometer, and ANSYS software, respectively. A much higher wear rate and more severe wear scars appeared under multi-directional motion. Flexion/extension motion of 7.5° lead to more severe wear than that under axial rotation motion of 4°. The above results were closely related to the contact compression stress and shear stress. The wear surface in FE motion showed typical linear wear scratches while revealing obvious arc-shaped wear tracks in AR motion. However, the central zone of both ball and socket components revealed more severe wear tracks than that in the edge zone under these two different motions. The dominant wear mechanism was plowing/scratching and abrasive wear as well as a little oxidation wear for the titanium socket while it was scratching damage with adhesive wear and fatigue wear due to plastic deformation under cyclic load and motion profiles for the UHMWPE ball. PMID:27040218

  19. A new way to measure supermassive black hole spin in accretion disc-dominated active galaxies

    OpenAIRE

    Done, C.; Jin, C; Middleton, M; Ward, M.

    2013-01-01

    We show that disc continuum fitting can be used to constrain black hole spin in a subclass of narrow-line Seyfert 1 (NLS1) active galactic nuclei as their low mass and high mass accretion rate means that the disc peaks at energies just below the soft X-ray bandpass. We apply the technique to the NLS1 PG1244+026, where the optical/UV/X-ray spectrum is consistent with being dominated by a standard disc component. This gives a best estimate for black hole spin which is low, with a firm upper lim...

  20. A new way to measure supermassive black hole spin in accretion disc dominated Active Galaxies

    OpenAIRE

    Done, C.; Jin, C; Middleton, M; Ward, M.

    2013-01-01

    We show that disc continuum fitting can be used to constrain black hole spin in a subclass of narrow-line Seyfert 1 (NLS1) active galactic nuclei as their low mass and high mass accretion rate means that the disc peaks at energies just below the soft X-ray bandpass. We apply the technique to the NLS1 PG1244+026, where the optical/UV/X-ray spectrum is consistent with being dominated by a standard disc component. This gives a best estimate for black hole spin which is low, with a firm upper lim...

  1. Myeloperoxidase Activities in Polymorphonuclear Leukocytes in Lumbar Disc Disease

    OpenAIRE

    Mehmet ŞENOĞLU; Ergul Belge KURUTAŞ; İdris ALTUN; Yalçın ATLI; Vedat NACİTARHAN

    2009-01-01

    Objectives: The exact pathogenesis of lumbar pain and radiculopathy is often poorly understood. Although nerve root entrapment resulting in mechanical pressure has been the most widely held concept to explain radiculopathy and lumbar pain, much of the recent research work increasingly supports an inflammatory reaction occurring in the lumbar intervertebral disc tissue. In this study, we aimed to show the role of Myeloperoxidase as an inflammatory marker and the correlation of inflammation wit...

  2. Discover人工颈椎间盘置换治疗颈椎间盘退变性疾病的临床疗效%Outcome of discover cervical artificial disc replacement for degenerativedisc disease of the cervical spine

    Institute of Scientific and Technical Information of China (English)

    何智勇; 李开南; 聂海; 母建松; 兰海

    2012-01-01

    Objective To estimate the clinical effects on Discover cervical artificial disc replacement for degenerative disc disease of the cervical spine. Methods A total of 20 patients with cervical disc degeneration, whose pain is not relieved adequately with six weeks of conservative care and daily activities become difficult, were chosed in this study between January 2007 and August 2011. The clinical outcomes were assessed using neck disable index (NDI) and visual analogue scale ( VAS) and Odora scale before surgery and 1、6、12、24 months after surgery. Imageological examination included X ray, cervical CT scanning and MR imaging. Results There are 26 levels in 20 patients performing cervical disc replacement and the follow-up period was 24 months. The NDI, VAS of neck pain, VAS of arm pain were from (23. 82 ±2. 87)、(5.90 ±0. 35)、(5. 91 ±1.63) before sugery to (5. 21 ± 1. 12)、(1. 62 ±0. 87)、(0. 97 ±0. 65) 2 years after sugery. Odom scale were excellent or good in all palienls. The operation time was 60-210 minutes and the estimated blood loss was 70 - 350 milliliter. The motion function of cervical artificial disc implanted was very good with imageology evaluation. The prosthesis moved forward 3 mm in one patient, and another patient had heterotopic ossification 12 months after surgery. Conclusion Discover cervical artificial disc replacement for degenerative disc disease of the cervical spine is safe and effective, however, further study should be conducted to determine the long term outcome.%目的 评价Discover人工颈椎间盘置换治疗颈椎间盘退变性疾病的临床疗效.方法 2007年1月~2011年8月,20例颈椎间盘退变突出经保守治疗无效的患者行人工颈椎间盘置换术.患者术前、术后1、6、12、24个月时使用颈椎功能障碍指数(neck disable index,NDI)、疼痛视觉模拟疼痛量表(visual analogue scale,VAS)进行疗效评估,手术效果采用Odom法评价.影像学检查包括颈椎动力位X

  3. Textured bearing surface in artificial joints to reduce macrophage activation

    Science.gov (United States)

    Nakanishi, Yoshitaka; Nishi, Naoki; Chikaura, Hiroto; Nakashima, Yuta; Miura, Hiromasa; Higaki, Hidehiko; Mizuta, Hiroshi; Iwamoto, Yukihide; Fujiwara, Yukio; Komohara, Yoshihiro; Takeya, Motohiro

    2015-12-01

    Micro slurry-jet erosion has been proposed as a precision machining technique for the bearing surfaces of artificial joints in order to reduce the total amount of polyethylene wear and to enlarge the size of the wear debris. The micro slurry-jet erosion method is a wet blasting technique which uses alumina particles as the abrasive medium along with compressed air and water to create an ideal surface. Pin-on-disc wear tests with multidirectional sliding motion on the textured surface of a \\text{Co}-\\text{Cr}-\\text{Mo} alloy counterface for polyethylene resulted in both a reduction of wear as well as enlargement of the polyethylene debris size. In this study, primary human peripheral blood mononuclear phagocytes were incubated with the debris, and it was elucidated that the wear debris generated on the textured surface regulated secretion of the proinflammatory cytokines IL-6 and TNF-α, indicating a reduction in the induced tissue reaction and joint loosening.

  4. Clinical and radiographic results of cervical artificial disc arthroplasty: over three years follow-up cohort study

    Institute of Scientific and Technical Information of China (English)

    TIAN Wei; HAN Xiao; LIU Bo; LI Qin; HU Lin; LI Zhi-yu; YUAN Qiang; HE Da; XING Yong-gang

    2010-01-01

    Background Theoretic advantages of cervical disc arthroplasty include preservation of normal motion and biomechanics in the cervical spine, and reduction of adjacent-segment degeneration. The clinical and radiographic effects of cervical disc arthroplasty in short term have been ascertained. The aim of this study is to research the data of mid-term results.Methods In this prospective cohort study, 50 patients who underwent cervical disc arthroplasty from December 2003 to January 2006 were enrolled. There were 39 patients who received 1-level disc arthroplasty, and 11 patients received 2-level disc arthroplasty, with an average age of 50.9 years (range from 29 to 73). The median follow-up was 41.85months (range from 36.00-55.63 months). Patients were followed prospectively with respect to their symptoms,neurologic signs, and radiographic results.Results The median value of Japanese Orthopaedic Association (JOA) score was 14.0 before surgery, and 16.5 at the most recent follow-up (P <0.01). The median value of the recovery rate of the JOA score was 92.2%. The preoperative range of motion (ROM) at the indexed level was (10.40±4.97)°, which has significantly correlated with the most recent follow-up ROM which was (8.56±4.76)° (P <0.05, r=0.33). The ROM at the operative level at the most recent follow-upwas greater than the value at the 3-month follow-up of (7.52±3.37)° (P <0.05). The preoperative functional spinal unit (FSU) angulation was (-0.96±6.52)°, which was not significantly correlated with that of the most recent follow-up value of (-2.65±7.95)° (P <0.01, r=0.53). The preoperative endplate angulation was (2.61±4.85)°, which had no significant correlation with that of the most recent follow-up value of (0.71±6.41)° (p >0.05).Conclusions The clinical and radiographic results of cervical disc arthroplasty are good in mid-term follow-up. The normal range of motion of the operated level and the biomechanics in the cervical spine are well

  5. Metallocarbene Artificial Enzymes : Extending Transition Metal Selectivity and Protein Activity

    NARCIS (Netherlands)

    Basauri Molina, M.

    2015-01-01

    A series of new semi-synthetic metalloprotein hybrids were created via the covalent binding of organometallic species in the active site of lipases, accordingly resulting in the first active site-directed (ASD) homogeneous artificial metalloenzymes. The use of this method promises the generation of

  6. Artificial cervical disc replacement and anterior cervical decompression and fusion for the treatment of single segmental cervical disc herniation:a 3-year follow-up%颈椎人工间盘置换与前路减压融合修复单节段颈椎间盘突出症:3年随访

    Institute of Scientific and Technical Information of China (English)

    程俊杰; 眭江涛; 马原; 田慧中

    2015-01-01

    stages. Artificial disc replacement can not only play a role in mitigation of cervical disease neurological symptoms and signs, but also maintain stability and semental activity of cervical spine, and reduce secondary adjacent segmental degeneration. These two methods which applied in cervical degenerative intervertebral disc herniation stil remain controversial. OBJECTIVE:To investigate the short-term effect of artificial cervical disc replacement and anterior cervical decompression and fusion for the treatment of single segmental cervical disc herniation. METHODS:Total y 48 patients with single segment radiculopathy or myelopathy cervical diseases induced by cervical disc herniation that required surgery and received a three-month fol ow-up were included and retrospectively analyzed. These patients were divided into replacement group (n=21) and fusion group (n=27) according to the different repair programs. Patients in the replacement group were subjected to Prestige LP cervical artificial disc replacement, and patients in the fusion group were subjected to disc fusion using interbody fusion cage of Johnson or al ogeneic fibularing. They were fol owed up at 1 week, 3, 6, 12, 24, 36 months after treatment. Complications were recorded during the fol ow-up. The pain of patients was evaluated using neck and upper limb pain visual analogue scale scores. The therapeutic effect was evaluated using Japanese Orthopaedic Association (JOA) score. The clinical symptoms improvement and daily functional status of patients after treatment were evaluated using cervical disability index. RESULTS AND CONCLUSION:During the final fol ow-up, the fusion rate in fusion group was 93%(25/27). Comparisons between groups:at the 1 week and final fol ow-up after treatment, the visual analog scale scores of neck and upper limbs and cervical dysfunction indexes were al lower than those before treatment;the Japanese Orthopaedic Association scores were higher than those before treatment (P0.05). The

  7. A case of unilateral optic disc swelling with chronic active Epstein–Barr virus infection

    OpenAIRE

    Aizawa, Naoko; Nakazawa, Toru; Shimura, Masahiko

    2010-01-01

    Ocular complications of chronic active Epstein–Barr virus (EBV) infection have rarely been reported and are usually associated with systemic symptoms. We described a 17-year-old boy with unilateral optic disc swelling without any systemic symptoms at the initial onset. Antibody titers to EBV were markedly elevated. Treatment with immunosuppressants and corticosteroids dramatically relieved all his symptoms, including unilateral optic swelling and visual field abnormalities.

  8. Paraspinal muscle activation in accordance with mechanoreceptors in the intervertebral discs.

    Science.gov (United States)

    Kim, Young Eun; Choi, Hae Won

    2013-02-01

    Paraspinal muscle forces were derived computationally based on the hypothesis that the intervertebral disc has a transducer function and the muscle is activated according to a sensor-driving control mechanism. A three-dimensional finite element model of the musculoskeletal system, which consisted of a detailed whole lumbar spine, pelvis, simplified trunk model, and muscles, was developed and combined with an optimization technique to calculate muscle forces in isometric forward flexed and erect standing postures. Minimization of deviations in the nucleus pressure and averaged tensile stress in the annulus fibers at five discs was used for muscle force calculations. The results indicated that all the muscles were properly activated to maintain posture and stabilize the lumbar spine. The nucleus pressure difference was decreased during the iterative calculations and its resulting value at the L4/L5 level was consistent with in vivo measurements. Muscle activation produced vertebra motion, which resulted in a relatively uniform stress distribution in the intervertebral discs. This can minimize the risk of injury at a specific level and increase the ability of the spine to sustain a load. PMID:23513985

  9. A Bayesian Framework for Active Artificial Perception

    OpenAIRE

    Ferreira, Joao; Lobo, Jorge; Bessiere, Pierre; Castelo-Branco, M; Dias, Jorge

    2012-01-01

    In this text, we present a Bayesian framework for active multimodal perception of 3D structure and motion. The design of this framework finds its inspiration in the role of the dorsal perceptual pathway of the human brain. Its composing models build upon a common egocentric spatial configuration that is naturally fitting for the integration of readings from multiple sensors using a Bayesian approach. In the process, we will contribute with efficient and robust probabilistic solutions for cycl...

  10. A Bayesian framework for active artificial perception.

    Science.gov (United States)

    Ferreira, João Filipe; Lobo, Jorge; Bessière, Pierre; Castelo-Branco, Miguel; Dias, Jorge

    2013-04-01

    In this paper, we present a Bayesian framework for the active multimodal perception of 3-D structure and motion. The design of this framework finds its inspiration in the role of the dorsal perceptual pathway of the human brain. Its composing models build upon a common egocentric spatial configuration that is naturally fitting for the integration of readings from multiple sensors using a Bayesian approach. In the process, we will contribute with efficient and robust probabilistic solutions for cyclopean geometry-based stereovision and auditory perception based only on binaural cues, modeled using a consistent formalization that allows their hierarchical use as building blocks for the multimodal sensor fusion framework. We will explicitly or implicitly address the most important challenges of sensor fusion using this framework, for vision, audition, and vestibular sensing. Moreover, interaction and navigation require maximal awareness of spatial surroundings, which, in turn, is obtained through active attentional and behavioral exploration of the environment. The computational models described in this paper will support the construction of a simultaneously flexible and powerful robotic implementation of multimodal active perception to be used in real-world applications, such as human-machine interaction or mobile robot navigation. PMID:23014760

  11. Application of finite element analysis in a biomechanical study on artificial lumbar disc%有限元分析在腰椎人工椎间盘生物力学研究中的应用

    Institute of Scientific and Technical Information of China (English)

    陈小龙; 海涌; 关立; 刘玉增

    2015-01-01

    Lumbar disc herniation is one of the major causes of chronic low back pain. Fusion surgery is the gold standard in surgical treatment of the disease, while adjacent segment degeneration is often resulted from the fusion surgery. In order to keep normal motion of the disc, artiifcial disc replacement has been put forward. In the past 50 years, the technology has developed from basic research and animal experiment stage to clinical application stage, which has become a routine treatment option for chronic low back pain. In recent 20 years, there has been many clinical and biomechanical research reports at home and abroad. Along with the advance of the technology, finite element method has been increasingly used in the biomechanical study on artificial lumbar disc. A large number of studies show that the clinical outcomes of disc prostheses are good, while the design and application of artiifcial intervertebral disc remain to be improved. By using three-dimensional ( 3 D ) ifnite element method, the mechanical properties can be obtained through the simulated body condition and simple physical experiment of artiifcialdisc prostheses, so as to reflect the mechanical changes of artificial disc in the process of physiological and pathological processes. The ifnite elementmethod can be used to analyze the stress and strain of components with complex morphology, structure, material and loading condition, with the advantages of comprehensive mechanical properties, repeatability, high-level controllability, etc. In this paper, the characteristics of several kinds of commonly used ifnite element analysis softwares are introduced, and the research results of ifnite elementmethod in artiifcial disc replacement and the effects of artiifcial disc implantation on spinal biomechanics are summarized. When compared with in vitro experiment, the finite element method has its own advantages and disadvantages. It is thought that more meaningful results can be achieved through the

  12. Activated sludge process based on artificial neural network

    Institute of Scientific and Technical Information of China (English)

    张文艺; 蔡建安

    2002-01-01

    Considering the difficulty of creating water quality model for activated sludge system, a typical BP artificial neural network model has been established to simulate the operation of a waste water treatment facilities. The comparison of prediction results with the on-spot measurements shows the model, the model is accurate and this model can also be used to realize intelligentized on-line control of the wastewater processing process.

  13. Asset Inequality and Economic Activity in Artificial Societies

    Science.gov (United States)

    Kikuchi, Toshiko

    In this paper, using multi-agent simulations, the effect asset inequality has on an artificial society is analyzed. It is shown that it is possible for a sustainable society to decrease in asset inequality and at the same time increase economic activity. In sustainable societies, the asset inequality increases as the consumption tax rate is raised, and in artificial societies where the tax rate is the same, inequality increases in the society in which agents with even small a surplus undertake unselfish actions. In sustainable societies which employ both income and consumption tax, an increase in asset inequalities leads to an increase economic activity. But, in sustainable societies which levy only the income tax, this result does not necessarily hold. These results show that if economic activity is increased in sustainable societies where the consumption tax rate is raised for the fiscal stability, an inequality expansion is an acceptable consequence. However, the sustainable society with the highest economic activity is realized when only the income tax is levied. In sustainable societies which levy only the income tax, it is possible to decrease inequality while simultaneously increasing economic activity.

  14. Finite element simulations of the active stress in the imaginal disc of the Drosophila Melanogaster.

    Science.gov (United States)

    Pettinati, V; Ambrosi, D; Ciarletta, P; Pezzuto, S

    2016-09-01

    During the larval stages of development, the imaginal disc of Drosphila Melanogaster is composed by a monolayer of epithelial cells, which undergo a strain actively produced by the cells themselves. The well-organized collective contraction produces a stress field that seemingly has a double morphogenetic role: it orchestrates the cellular organization towards the macroscopic shape emergence while simultaneously providing a local information on the organ size. Here we perform numerical simulations of such a mechanical control on morphogenesis at a continuum level, using a three-dimensional finite model that accounts for the active cell contraction. The numerical model is able to reproduce the (few) known qualitative characteristics of the tensional patterns within the imaginal disc of the fruit fly. The computed stress components slightly deviate from planarity, thus confirming the previous theoretical assumptions of a nonlinear elastic analytical model, and enforcing the hypothesis that the spatial variation of the mechanical stress may act as a size regulating signal that locally scales with the global dimension of the domain. PMID:26765274

  15. Chemotaxis of artificial microswimmers in active density waves.

    Science.gov (United States)

    Geiseler, Alexander; Hänggi, Peter; Marchesoni, Fabio; Mulhern, Colm; Savel'ev, Sergey

    2016-07-01

    Living microorganisms are capable of a tactic response to external stimuli by swimming toward or away from the stimulus source; they do so by adapting their tactic signal transduction pathways to the environment. Their self-motility thus allows them to swim against a traveling tactic wave, whereas a simple fore-rear asymmetry argument would suggest the opposite. Their biomimetic counterpart, the artificial microswimmers, also propel themselves by harvesting kinetic energy from an active medium, but, in contrast, lack the adaptive capacity. Here we investigate the transport of artificial swimmers subject to traveling active waves and show, by means of analytical and numerical methods, that self-propelled particles can actually diffuse in either direction with respect to the wave, depending on its speed and waveform. Moreover, chiral swimmers, which move along spiraling trajectories, may diffuse preferably in a direction perpendicular to the active wave. Such a variety of tactic responses is explained by the modulation of the swimmer's diffusion inside traveling active pulses. PMID:27575185

  16. Chemotaxis of artificial microswimmers in active density waves

    Science.gov (United States)

    Geiseler, Alexander; Hänggi, Peter; Marchesoni, Fabio; Mulhern, Colm; Savel'ev, Sergey

    2016-07-01

    Living microorganisms are capable of a tactic response to external stimuli by swimming toward or away from the stimulus source; they do so by adapting their tactic signal transduction pathways to the environment. Their self-motility thus allows them to swim against a traveling tactic wave, whereas a simple fore-rear asymmetry argument would suggest the opposite. Their biomimetic counterpart, the artificial microswimmers, also propel themselves by harvesting kinetic energy from an active medium, but, in contrast, lack the adaptive capacity. Here we investigate the transport of artificial swimmers subject to traveling active waves and show, by means of analytical and numerical methods, that self-propelled particles can actually diffuse in either direction with respect to the wave, depending on its speed and waveform. Moreover, chiral swimmers, which move along spiraling trajectories, may diffuse preferably in a direction perpendicular to the active wave. Such a variety of tactic responses is explained by the modulation of the swimmer's diffusion inside traveling active pulses.

  17. Impaired hippocampal activity at the goal zone on the place preference task in a DISC1 mouse model.

    Science.gov (United States)

    Hayashi, Yuichiro; Sawa, Akira; Hikida, Takatoshi

    2016-05-01

    Learning deficit is a clinical feature of many mental disorders and is hypothesized to result from an inability to integrate information in neural systems. We showed that transgenic mice expressing a dominant-negative form of DISC1, a risk gene for neuropsychiatric disorders, exhibited impaired performance in a reward-place association task when combined with a mild isolation stress. CA1 cells in the mutant mice showed normal place cell properties, but their activity at the goal zone was diminished. This abnormality in hippocampal activity at the goal zone during the task may underlie the learning deficit observed in the DISC1 mutant mice. PMID:26497623

  18. Screening of hyaluronic acid-poly(ethylene glycol) composite hydrogels to support intervertebral disc cell biosynthesis using artificial neural network analysis.

    Science.gov (United States)

    Jeong, Claire G; Francisco, Aubrey T; Niu, Zhenbin; Mancino, Robert L; Craig, Stephen L; Setton, Lori A

    2014-08-01

    Hyaluronic acid (HA)-poly(ethylene glycol) (PEG) composite hydrogels have been widely studied for both cell delivery and soft tissue regeneration applications. A very broad range of physical and biological properties have been engineered into HA-PEG hydrogels that may differentially affect cellular "outcomes" of survival, synthesis and metabolism. The objective of this study was to rapidly screen multiple HA-PEG composite hydrogel formulations for an effect on matrix synthesis and behaviors of nucleus pulposus (NP) and annulus fibrosus (AF) cells of the intervertebral disc (IVD). A secondary objective was to apply artificial neural network analysis to identify relationships between HA-PEG composite hydrogel formulation parameters and biological outcome measures for each cell type of the IVD. Eight different hydrogels were developed from preparations of thiolated HA (HA-SH) and PEG vinylsulfone (PEG-VS) macromers, and used as substrates for NP and AF cell culture in vitro. Hydrogel mechanical properties ranged from 70 to 489kPa depending on HA molecular weight, and measures of matrix synthesis, metabolite consumption and production and cell morphology were obtained to study relationships to hydrogel parameters. Results showed that NP and AF cell numbers were highest upon the HA-PEG hydrogels formed from the lower-molecular-weight HA, with evidence of higher sulfated glycosaminoglycan production also upon lower-HA-molecular-weight composite gels. All cells formed more multi-cell clusters upon any HA-PEG composite hydrogel as compared to gelatin substrates. Formulations were clustered into neurons based largely on their HA molecular weight, with few effects of PEG molecular weight observed on any measured parameters. PMID:24859415

  19. A Survey of 6,300 Genomic Fragments for cis-Regulatory Activity in the Imaginal Discs of Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Aurélie Jory

    2012-10-01

    Full Text Available Over 6,000 fragments from the genome of Drosophila melanogaster were analyzed for their ability to drive expression of GAL4 reporter genes in the third-instar larval imaginal discs. About 1,200 reporter genes drove expression in the eye, antenna, leg, wing, haltere, or genital imaginal discs. The patterns ranged from large regions to individual cells. About 75% of the active fragments drove expression in multiple discs; 20% were expressed in ventral, but not dorsal, discs (legs, genital, and antenna, whereas ∼23% were expressed in dorsal but not ventral discs (wing, haltere, and eye. Several patterns, for example, within the leg chordotonal organ, appeared a surprisingly large number of times. Unbiased searches for DNA sequence motifs suggest candidate transcription factors that may regulate enhancers with shared activities. Together, these expression patterns provide a valuable resource to the community and offer a broad overview of how transcriptional regulatory information is distributed in the Drosophila genome.

  20. Artificial Neural Network Characteristic For Neutron Activation Analysis

    International Nuclear Information System (INIS)

    Neutron activation analysis (NAA) is one of analysis methods for identification of elements from material. Irradiated unknown material could be identified by gamma spectrum pattern analysis. The recognition process will be done easily if we have a smart system. One of the smart system choices was artificial neural network (ANN). The gamma spectrum emitted from radioactive nuclide has specific pattern, therefore smart system will try to classify the input data. Firstly, Hp-Ge detector detects gamma radiation from material, then the gamma radiations is counted by multi channel analysis instrument (MCA). The smart system based ANN system was tested to identify 50 material, in which the system has been trained by using one data only for each classifications. The result showed that the ANN appreciates 100% identification capability or has a good performance

  1. Design principle and development tendency of artificial lumbar disc prosthesis%人工腰椎间盘假体设计原理研究及未来趋势发展

    Institute of Scientific and Technical Information of China (English)

    董可欣; 马德春; 李秋菊; 张丽; 李磊

    2014-01-01

    BACKGROUND:Artificial lumbar disc replacement is a new choice for the treatment of degenerative disc disease, and preserves lumbar vertebra’s biomechanical characteristics during pain elimination. The design of the prosthesis structure and material needs further study and validation. OBJECTIVE:To review the structure and material types of presently designed artificial lumbar discs, then to discuss the trends in the optimization design of prosthesis. METHODS:The PubMed database, China National Knowledge Infrastructure database and Chinese BioMedical Literature Database were searched for related articles concerning artificial lumbar disc and type and biomechanics of nucleus pulposus prosthesis material published from January 2005 to February 2013 by the first author. Key words were“artificial lumbar disc, principle of prosthesis design, structure, material, clinical trials”in Chinese and“artificial lumbar disc, total disc replacement, structure, material, clinical trial”in English. Repetitive and old studies were excluded. 135 articles were found, but 36 articles were included for review. RESULTS AND CONCLUSION:At present, the materials for intervertebral discs include cobalt-chromium al oy, ceramics, stainless steel, titanium al oy and ultrahigh molecular weight polyethylene. Artificial lumbar disc is commonly made by different materials. Bryan prosthesis is most commonly used in the clinic. Three-dimensional finite element analysis, in vitro trial and clinical studies verified its good biomechanical property. The successful rate of replacement was high. Nucleus prosthesis contains prefabricated type and situ polymerization type, and obtains smal injury, so it is a hot focus in present study, but it cannot achieve biomechanical function of human nucleus pulposus. To dig novel material is a future direction for designing individual prosthesis. The prosthetic structure and biomaterial design experience constant improvement and development. This study

  2. Dynamic phenomena and human activity in an artificial society

    Science.gov (United States)

    Grabowski, A.; Kruszewska, N.; Kosiński, R. A.

    2008-12-01

    We study dynamic phenomena in a large social network of nearly 3×104 individuals who interact in the large virtual world of a massive multiplayer online role playing game. On the basis of a database received from the online game server, we examine the structure of the friendship network and human dynamics. To investigate the relation between networks of acquaintances in virtual and real worlds, we carried out a survey among the players. We show that, even though the virtual network did not develop as a growing graph of an underlying network of social acquaintances in the real world, it influences it. Furthermore we find very interesting scaling laws concerning human dynamics. Our research shows how long people are interested in a single task and how much time they devote to it. Surprisingly, exponent values in both cases are close to -1 . We calculate the activity of individuals, i.e., the relative time daily devoted to interactions with others in the artificial society. Our research shows that the distribution of activity is not uniform and is highly correlated with the degree of the node, and that such human activity has a significant influence on dynamic phenomena, e.g., epidemic spreading and rumor propagation, in complex networks. We find that spreading is accelerated (an epidemic) or decelerated (a rumor) as a result of superspreaders’ various behavior.

  3. Photochemical chlorine and bromine activation from artificial saline snow

    Directory of Open Access Journals (Sweden)

    S. N. Wren

    2013-05-01

    Full Text Available The activation of reactive halogen species – particularly Cl2 – from sea ice and snow surfaces is not well understood. In this study, we used a photochemical snow reactor coupled to a chemical ionization mass spectrometer to investigate the production of Br2, BrCl and Cl2 from NaCl/NaBr-doped artificial snow samples. At temperatures above the NaCl-water eutectic, illumination of samples (λ > 310 nm in the presence of gas phase O3 led to the accelerated release of Br2, BrCl and the release of Cl2 in a process that was significantly enhanced by acidity, high surface area and additional gas phase Br2. Cl2 production was only observed when both light and ozone were present. The total halogen release depended on [O3] and pre-freezing [NaCl]. Our observations support a "halogen explosion" mechanism occurring within the snowpack which is initiated by heterogeneous oxidation, and propagated by Br2 or BrCl photolysis and by recycling of HOBr and HOCl into the snowpack. Our study implicates an important role for active chemistry occurring within the interstitial air of aged (i.e., acidic snow for halogen activation at polar sunrise.

  4. Photochemical chlorine and bromine activation from artificial saline snow

    Directory of Open Access Journals (Sweden)

    S. N. Wren

    2013-10-01

    Full Text Available The activation of reactive halogen species – particularly Cl2 – from sea ice and snow surfaces is not well understood. In this study, we used a photochemical snow reactor coupled to a chemical ionization mass spectrometer to investigate the production of Br2, BrCl and Cl2 from NaCl/NaBr-doped artificial snow samples. At temperatures above the NaCl-water eutectic, illumination of samples (λ > 310 nm in the presence of gas phase O3 led to the accelerated release of Br2, BrCl and the release of Cl2 in a process that was significantly enhanced by acidity, high surface area and additional gas phase Br2. Cl2 production was only observed when both light and ozone were present. The total halogen release depended on [ozone] and pre-freezing [NaCl]. Our observations support a "halogen explosion" mechanism occurring within the snowpack, which is initiated by heterogeneous oxidation and propagated by Br2 or BrCl photolysis and by recycling of HOBr and HOCl into the snowpack. Our study implicates this important role of active chemistry occurring within the interstitial air of aged (i.e. acidic snow for halogen activation at polar sunrise.

  5. Active galactic nuclei at z ~ 1.5: I. Spectral energy distribution and accretion discs

    CERN Document Server

    Capellupo, Daniel M; Lira, Paulina; Trakhtenbrot, Benny; Mejía-Restrepo, Julían

    2014-01-01

    The physics of active super massive black holes (BHs) is governed by their mass (M_BH), spin (a*) and accretion rate ($\\dot{M}$). This work is the first in a series of papers with the aim of testing how these parameters determine the observable attributes of active galactic nuclei (AGN). We have selected a sample in a narrow redshift range, centered on z~1.55, that covers a wide range in M_BH and $\\dot{M}$, and are observing them with X-shooter, covering rest wavelengths ~1200-9800 \\AA. The current work covers 30 such objects and focuses on the origin of the AGN spectral energy distribution (SED). After estimating M_BH and $\\dot{M}$ based on each observed SED, we use thin AD models and a Bayesian analysis to fit the observed SEDs in our sample. We are able to fit 22/30 of the SEDs. Out of the remaining 8 SEDs, 3 can be fit by the thin AD model by correcting the observed SED for reddening within the host galaxy and 4 can be fit by adding a disc wind to the model. In four of these 8 sources, Milky Way-type exti...

  6. The gas metallicity gradient and the star formation activity of disc galaxies

    CERN Document Server

    Tissera, Patricia B; Sillero, Emanuel; Vilchez, Jose M

    2015-01-01

    We study oxygen abundance profiles of the gaseous disc components in simulated galaxies in a hierarchical universe. We analyse the disc metallicity gradients in relation to the stellar masses and star formation rates of the simulated galaxies. We find a trend for galaxies with low stellar masses to have steeper metallicity gradients than galaxies with high stellar masses at z ~0. We also detect that the gas-phase metallicity slopes and the specific star formation rate (sSFR) of our simulated disc galaxies are consistent with recently reported observations at z ~0. Simulated galaxies with high stellar masses reproduce the observed relationship at all analysed redshifts and have an increasing contribution of discs with positive metallicity slopes with increasing redshift. Simulated galaxies with low stellar masses a have larger fraction of negative metallicity gradients with increasing redshift. Simulated galaxies with positive or very negative metallicity slopes exhibit disturbed morphologies and/or have a clo...

  7. Extracellular enzyme activities and nutrient availability during artificial groundwater recharge.

    Science.gov (United States)

    Kolehmainen, Reija E; Korpela, Jaana P; Münster, Uwe; Puhakka, Jaakko A; Tuovinen, Olli H

    2009-02-01

    Natural organic matter (NOM) removal is the main objective of artificial groundwater recharge (AGR) for drinking water production and biodegradation plays a substantial role in this process. This study focused on the biodegradation of NOM and nutrient availability for microorganisms in AGR by the determination of extracellular enzyme activities (EEAs) and nutrient concentrations along a flow path in an AGR aquifer (Tuusula Water Works, Finland). Natural groundwater in the same area but outside the influence of recharge was used as a reference. Determination of the specific alpha-d-glucosidase (alpha-Glu), beta-d-glucosidase (beta-Glu), phosphomonoesterase (PME), leucine aminopeptidase (LAP) and acetate esterase (AEST) activities by fluorogenic model substrates revealed major increases in the enzymatic hydrolysis rates in the aquifer within a 10m distance from the basin. The changes in the EEAs along the flow path occurred simultaneously with decreases in nutrient concentrations. The results support the assumption that the synthesis of extracellular enzymes in aquatic environments is up and down regulated by nutrient availability. The EEAs in the basin sediment and pore water samples (down to 10cm) were in the same order of magnitude as in the basin water, suggesting similar nutritional conditions. Phosphorus was likely to be the limiting nutrient at this particular AGR site. Furthermore, the extracellular enzymes functioned in a synergistic and cooperative way. PMID:19028394

  8. Stellar disc-active galactic nucleus alignments in the SDSS-DR7

    CERN Document Server

    Lagos, Claudia del P; Strauss, Michael A; Cora, Sofia A; Hao, Lei

    2010-01-01

    We determine the intrinsic shapes and orientations of 27,450 type I and II active galactic nucleus (AGN) galaxies in the spectroscopic sample of the Sloan Digital Sky Survey Data Release 7, by studying the distribution of projected axis ratios of AGN hosts. Our aim is to study possible alignments between the AGN and host galaxy systems (e.g. the accretion disc and the galaxy angular momentum) and the effect of dust obscuration geometry on the AGN type. We define control samples of non-AGN galaxies that mimic the morphology, colour, luminosity and concentration distributions of the AGN population, taking into account the effects of dust extinction and reddening. By assuming that AGN galaxies have the same underlying three-dimensional shape distribution as their corresponding control samples, we find that the spiral and elliptical type I AGN populations are strongly biased toward face-on galaxies, while ellipticals and spirals type II AGN are biased toward edge-on orientations. These findings rule out random or...

  9. COMPARATIVE STUDY OF ANTIMICROBIAL ACTIVITY OF CEFTRIAXONE IN COMBINATION WITH SULBACTAM AND TAZOBACTAM USING DISC DIFFUSION METHOD

    OpenAIRE

    Kumar Vinay BM; Sharadamma KC; Rajpurohit Himanshu; Radhakrishna PM

    2012-01-01

    The present study includes comparative analysis of the antimicrobial effect of combination of ceftriaxone/sulbactam and ceftriaxone/tazobactam against Staphylococcus aureus (S. aureus).Isolate of β-lactamase producing S. aureus was cultured. Antibiotic discs of ceftriaxone/sulbactam and ceftriaxone/tazobactam combinations were prepared and their antimicrobial activity was compared against zone of inhibition produced in cultured isolates. National Committee for Clinical Laboratory Standards zo...

  10. Accretion disc dynamo activity in local simulations spanning weak-to-strong net vertical magnetic flux regimes

    CERN Document Server

    Salvesen, Greg; Armitage, Philip J; Begelman, Mitchell C

    2015-01-01

    Strongly magnetized accretion discs around black holes have attractive features that may explain enigmatic aspects of X-ray binary behaviour. The structure and evolution of these discs are governed by a dynamo-like mechanism, which channels part of the accretion power liberated by the magnetorotational instability (MRI) into an ordered toroidal magnetic field. To study dynamo activity, we performed three-dimensional, stratified, isothermal, ideal magnetohydrodynamic shearing box simulations. The strength of the self-sustained toroidal magnetic field depends on the net vertical magnetic flux, which we vary across almost the entire range over which the MRI is linearly unstable. We quantify disc structure and dynamo properties as a function of the initial ratio of mid-plane gas pressure to vertical magnetic field pressure, $\\beta_0^{\\rm mid} = p_{\\rm gas} / p_B$. For $10^5 \\geq \\beta_0^{\\rm mid} \\geq 10$ the effective $\\alpha$-viscosity parameter scales as a power-law. Dynamo activity persists up to and includin...

  11. Artificial Limbs

    Science.gov (United States)

    ... you are missing an arm or leg, an artificial limb can sometimes replace it. The device, which ... activities such as walking, eating, or dressing. Some artificial limbs let you function nearly as well as ...

  12. Biomechanics of a Fixed–Center of Rotation Cervical Intervertebral Disc Prosthesis

    OpenAIRE

    Crawford, Neil R; Baek, Seungwon; Sawa, Anna G.U.; Safavi-Abbasi, Sam; Sonntag, Volker K.H.; Duggal, Neil

    2012-01-01

    Background Past in vitro experiments studying artificial discs have focused on range of motion. It is also important to understand how artificial discs affect other biomechanical parameters, especially alterations to kinematics. The purpose of this in vitro investigation was to quantify how disc replacement with a ball-and-socket disc arthroplasty device (ProDisc-C; Synthes, West Chester, Pennsylvania) alters biomechanics of the spine relative to the normal condition (positive control) and si...

  13. Recent development on surface modification of artificial disc material for wear resistance%人工椎间盘关节材料表面耐磨改性研究进展

    Institute of Scientific and Technical Information of China (English)

    王松; 廖振华; 刘宇宏; 刘伟强

    2013-01-01

    Generally titanium alloy and ultra-high molecular weight polyethylene (UHMWPE) are software materials in artificial disc joint material pairing, so their surface modification is important to improve the wear resistance and long-term stability of the prosthesis. The recent development to improve surface hardness and wear resistance of the titanium alloy by using heat treatment, micro-arc oxidation, surface infiltration elements, plated DLC films, laser surface modification and ion implantation technology are reviewed. Then the research to improve surface hardness and wear resistance of UHMWPE by plating DLC films are introduced. At last, the future trends of the artificial disc prosthesis wear resistance are analyzed.%钛合金和超高分子量聚乙烯(UHMWPE)在人工椎间盘关节材料配对中一般是软体材料,其表面改性对提高假体耐磨性能及长期稳定性有重要意义.主要介绍了采用热处理、微弧氧化、表面渗元素、表面镀DLC膜、激光表面改性、离子注入技术提高钛合金表面硬度和耐磨性的研究进展,以及采用表面镀DLC膜等提高UHMWPE表面硬度和耐磨性的研究现状,展望了人工椎间盘假体耐磨性研究的发展趋势.

  14. Effects of osmotic stress on antioxidant enzymes activities in leaf discs of PSAG12-IPT modified gerbera

    Institute of Scientific and Technical Information of China (English)

    LAI Qi-xian; BAO Zhi-yi; ZHU Zhu-jun; QIAN Qiong-qiu; MAO Bi-zeng

    2007-01-01

    Leaf senescence is often caused by water deficit and the chimeric gene PSAG12-IPT is an auto-regulated gene delaying leaf senescence. Using in vitro leaf discs culture system, the changes of contents of chlorophylls, carotenoids, soluble protein and thiobarbituric acid reactive substance (TBARS) and antioxidant enzymes activities were investigated during leaf senescence of PSAG12-IPT modified gerbera induced by osmotic stress compared with the control plant (wild type). Leaf discs were incubated in 20%, 40% (w/v) polyethylene glycol (PEG) 6 000 nutrient solution for 20 h under continuous light [130 μmol/(m2·s)]. The results showed that the contents of chlorophylls, carotenoids and soluble protein were decreased by osmotic stress with the decrease being more pronounced at 40% PEG, but that, at the same PEG concentration the decrease in the transgenic plants was significantly lower than that in the control plant. The activities of superoxide dismutase (SOD), catalases (CAT), ascorbate peroxidase (APX),guaiacol peroxidase (GPX) and dehydroascorbate reductase (DHAR) were stimulated by PEG treatment. However, the increases were higher in PSAG12-IPT transgenic plants than in the control plants, particularly at 40% PEG treatment. Lipid peroxidation (TBARS content) was increased by PEG treatment with the increase being much lower in transgenic plant than in the control plant.It could be concluded that the increases in the activities of antioxidant enzymes including SOD, CAT, APX, GPX and DHAR were responsible for the delay of leaf senescence induced by osmotic stress.

  15. ISSLS PRIZE WINNER: INHIBITION OF NF-κB ACTIVITY AMELIORATES AGE-ASSOCIATED DISC DEGENERATION IN A MOUSE MODEL OF ACCELERATED AGING

    Science.gov (United States)

    Nasto, Luigi A.; Seo, Hyoung-Yeon; Robinson, Andria R.; Tilstra, Jeremy S.; Clauson, Cheryl L.; Sowa, Gwendolyn A.; Ngo, Kevin; Dong, Qing; Pola, Enrico; Lee, Joon Y.; Niedernhofer, Laura J.; Kang, James D.; Robbins, Paul D.; Vo, Nam V.

    2012-01-01

    Study Design NF-κB activity was pharmacologically and genetically blocked in an accelerated aging mouse model to mitigate age-related disc degenerative changes. Objective To study the mediatory role of NF-κB signaling pathway in age-dependent intervertebral disc degeneration. Summary of Background Data Aging is a major contributor to intervertebral disc degeneration (IDD), but the molecular mechanism behind this process is poorly understood. NF-κB is a family of transcription factors which play a central role in mediating cellular response to damage, stress, and inflammation. Growing evidence implicates chronic NF-κB activation as a culprit in many aging-related diseases, but its role in aging-related IDD has not been adequately explored. We studied the effects of NF-κB inhibition on IDD using a DNA repair-deficient mouse model of accelerated aging (Ercc1-/Δ mice) previously been reported to exhibit age-related IDD. Methods Systemic inhibition of NF-κB activation was achieved either genetically by deletion of one allele of the NF-κB subunit p65 (Ercc1-/Δp65+/- mice) or pharmacologically by chronic intra-peritoneal administration of the Nemo Binding Domain (8K-NBD) peptide to block the formation of the upstream activator of NF-κB, IκB Inducible Kinase (IKK), in Ercc1-/Δ mice. Disc cellularity, total proteoglycan content and proteoglycan synthesis of treated mice and untreated controls were assessed. Results Decreased disc matrix proteoglycan content, a hallmark feature of IDD, and elevated disc NF-κB activity were observed in discs of progeroid Ercc1-/Δ mice and naturally aged wild-type compared to young WT mice. Systemic inhibition of NF-κB by the 8K-NBD peptide in Ercc1-/Δ mice increased disc proteoglycan synthesis and ameriolated loss disc cellularity and matrix proteoglycan. These results were confirmed genetically by using the p65 haploinsufficient Ercc1-/Δp65+/- mice. Conclusion These findings demonstrate that the IKK/NF-κB signaling pathway

  16. Discover颈人工椎间盘置换术联合颈椎前路减压融合术治疗颈椎病的临床疗效%The clinic effect of discover cervical artificial disc replacement combined with anterior cervical decompression and fusion in treatment of cervical spondylosis

    Institute of Scientific and Technical Information of China (English)

    吴兴林

    2014-01-01

    Objective To explore the clinic effect of discover cervical artificial disc replacement combined with anterior cervical decompression and fusion in treatment of cervical spondylosis. Methods 96 patients were selected from our hospital,and the they were evenly divied into two group by random,experimental group patients were treated with discover cervical artificial disc replacement combined with anterior cervical decompression,the control group patients were treated with anterior cervical decompression and fusion.Compared and analyzed the two groups'cervical spine,the average hospital stay,postoperative cervical fixation time,normal activity recovery time and clinical effect after treatment. Results The experimental group's cervical average activity was (44.6±4.7) degree which was higher than control group,and the difference was significantly(P < 0.05);The experimental group was shorter than control group in average hospital stay,postoperative cervical fixation time,normal activity recovery time,and the difference was significantly(P < 0.05);Experimental group's total effective rate was 97.9% which was higher than the control group(87.5%),and the difference was significantly(P<0.05). Conclusion Discover cervical artificial disc replacement combined with anterior cervical decompression and fusion can reduce the average hospital stay,postoperative cervical fixation time,normal activity recovery time,can ensure the patients's cervical average activity to recover normal,and can improve the clinical effect.%目的:探讨分析Discover颈人工椎间盘置换术联合颈椎前路减压融合术的临床疗效。方法选择我院96例患者,将其随机均分为两组,实验组行Discover颈人工椎间盘置换术联和颈椎前路减压融合术治疗;对照组行颈椎前路减压融合术治疗,比较患者术后颈椎活动度、平均住院时间、术后颈椎固定时间、恢复正常活动时间以及患者临床疗效,并进行统计学分析。

  17. Galaxy Zoo: the effect of bar-driven fueling on the presence of an active galactic nucleus in disc galaxies

    CERN Document Server

    Galloway, Melanie A; Fortson, Lucy F; Cardamone, Carolin N; Schawinski, Kevin; Cheung, Edmond; Lintott, Chris J; Masters, Karen L; Melvin, Thomas; Simmons, Brooke D

    2015-01-01

    We study the influence of the presence of a strong bar in disc galaxies which host an active galactic nucleus (AGN). Using data from the Sloan Digital Sky Survey and morphological classifications from the Galaxy Zoo 2 project, we create a volume-limited sample of 19,756 disc galaxies at $0.01

  18. COMPARATIVE STUDY OF ANTIMICROBIAL ACTIVITY OF CEFTRIAXONE IN COMBINATION WITH SULBACTAM AND TAZOBACTAM USING DISC DIFFUSION METHOD

    Directory of Open Access Journals (Sweden)

    Kumar Vinay BM

    2012-05-01

    Full Text Available The present study includes comparative analysis of the antimicrobial effect of combination of ceftriaxone/sulbactam and ceftriaxone/tazobactam against Staphylococcus aureus (S. aureus.Isolate of β-lactamase producing S. aureus was cultured. Antibiotic discs of ceftriaxone/sulbactam and ceftriaxone/tazobactam combinations were prepared and their antimicrobial activity was compared against zone of inhibition produced in cultured isolates. National Committee for Clinical Laboratory Standards zone diameter criteria was used to measure and evaluate the diameter of zones of inhibition.Zones of inhibition produced by ceftriaxone/tazobactam combination were larger than those produced by ceftriaxone/sulbactam combination indicating comparative advantages. The study reveals that as compared to sulbactam, tazobactam is adding more synergistic action to the ceftriaxone activity against S. aureus.

  19. Mid-term clinical outcome of Bryan artificial cervical disc replacement for cervical spondylosis and its effect on degeneration of adjacent discs%Bryan人工颈椎椎间盘置换术治疗颈椎病的中期临床效果及对邻近椎间盘退变的影响

    Institute of Scientific and Technical Information of China (English)

    王贝宇; 曾建成; 孔清泉; 刘浩; 丁琛; 胡韬; 石锐; 李涛; 洪瑛; 宋跃明; 刘立岷

    2011-01-01

    Objective To observe the clinical outcome of Bryan artificial cervical disc replacement for cervical spondylo-sis, and to investigate its effect on degeneration of adjacent discs in mid-term study. Methods From November 2004 to December 2007, 34 patients (38 discs) receiving Bryan artificial cervical disc replacement were included in this study. Clinical results were evaluated by SF-36 score, neck disability index (NDI) score, neck/arm pain visual anatague scale (VAS) scores and Odom' s scale. The data were collected before surgery and at 1 week ,3,6, 12, 24, 36, 48 and 60 months after surgery. Adjacent degeneration was assessed by scoring system of cervical disk degeneration based on neutral lateral radiographs before operation and 12, 24, 36, 48 and 60 months after surgery. Incidence of postoperative complications and reoper-ations were also recorded. Results The neurological symptoms of each patient were significantly alleviated in short term after operation. The postoperative SF-36 physical component score and SF-36 mental component score, NDI score and neck/arm pain VAS scores were significantly improved compared with those of pre-operation. In 36 and 48 months after surgey, excellent and good outcomes were observed , though there were some cases with decreased outcomes; sound outcomes were achieved at the final follow-up in all cases. Mild degeneration of adjacent discs occurred after operation, but there was no severe degeneration at the final follow-up. There was no prosthesis subsidence or excursion, no heterotopic ossification or spontaneous fusion, and no reoperation. Conclusion Bryan artificial disc replacement has a sound clinical outcome in mid-term and can protect against acceleration of adjacent discs degeneration.%目的 观察Bryan人工颈椎椎间盘置换术治疗颈椎病的中期临床效果,研究该术对邻近椎间盘的影响.方法 2004年11月~2007年12月间,对34例颈椎间盘突出症患者共38个节段实施Bryan人工颈椎

  20. Sorption and biodegradation of artificial sweeteners in activated sludge processes.

    Science.gov (United States)

    Tran, Ngoc Han; Gan, Jie; Nguyen, Viet Tung; Chen, Huiting; You, Luhua; Duarah, Ankur; Zhang, Lifeng; Gin, Karina Yew-Hoong

    2015-12-01

    There is limited information on the occurrence and removal of artificial sweeteners (ASs) in biological wastewater treatment plants, and in particular, the contribution of sorption and biodegradation to their removal. This study investigated the fate of ASs in both the aqueous and solid phases in a water reclamation plant (WRP). All the four targeted ASs, i.e. acesulfame (ACE), sucralose (SUC), cyclamate (CYC) and saccharine (SAC), were detected in both the aqueous and solid phases of raw influent and primary effluent samples. The concentrations of CYC and SAC in secondary effluent or MBR permeate were below their method detection limits. ACE and SUC were persistent throughout the WRP, whereas CYC and SAC were completely removed in biological treatment (>99%). Experimental results showed that sorption played a minor role in the elimination of the ASs due to the relatively low sorption coefficients (Kd), where Kd<500L/kg. In particular, the poor removal of ACE and SUC in the WRP may be attributed to their physiochemical properties (i.e. logKow<0 or logD<3.2) and chemical structures containing strong withdrawing electron functional groups in heterocyclic rings (i.e. chloride and sulfonate). PMID:26342347

  1. M obi-C 颈椎人工间盘置换治疗单节段颈椎间盘突出症的效果%Effect of Mobi-C cervical artificial disc replacement in the treatment of single proplase of cervical intervertebral disc

    Institute of Scientific and Technical Information of China (English)

    柳达; 黄瑛; 李彬; 贾长青; 许晓军; 梁峰; 付勤

    2013-01-01

    Objective:To research the short-term effect of Mobi-C cervical artificial disc replacement (CADR) therapy in patients with single proplase of cervical intervertebral disc .Methods:Mobi-C artificial cervical disc was applied to treat 12 cases of single proplase of cervical intervertebral disc .The data about clinical observation , imaging evaluation and questionnaire were collected at preoperative , postoperative ( 1-2 days ) and the end follow-up.Results:The patients were followed up for 6 to 24 months,average 13 months.All the patients were satisfactory to the outcome , excellent in 10 cases and good in 2 cases according to Odom criterion .The pain in upper limb and neck were significantly relieved, the VAS score immediately decreased 5.8 points after operation(P<0.05), and 5.5 points at the last follow-up(P<0.05).NDI and SF-36 improved obviously,which meant the patient′s quality of life improved obviously .Degeneration at the adjacent segments was not found in addition to 3 patient with heterotopic ossification .Conclusions:Mobi-C CADR therapy reserving mobility of cervical spine has a good effect in the early stage , and can improve the quality of life of the patients .%目的:探讨Mobi-C颈椎人工间盘置换治疗单节段颈椎间盘突出症的近期效果。方法:对应用Mobi-C颈椎人工间盘置换治疗的12例单节段颈椎间盘突出症患者于术前、术后(1~2 d )及末次随访时进行全面的影像学和临床评价,并进行问卷调查。结果:本组病例随访6~24月,平均13个月。 Odom临床疗效评价优10例,良2例。患者的颈部及上肢疼痛明显缓解,VAS评分术后下降了5.8分(P<0.05),末次随访时下降了5.5分(P<0.05)。颈椎功能障碍指数(NDI)和SF-36生活质量量表评分明显改善,患者的生活质量明显提高。除3例患者发生异位骨化外,未发现相邻节段退变加速。结论:保留颈椎活动度的Mobi-C颈椎人工间

  2. An artificial neural network to estimate physical activity energy expenditure and identify physical activity type from an accelerometer

    OpenAIRE

    Staudenmayer, John; Pober, David; Crouter, Scott; Bassett, David; Freedson, Patty

    2009-01-01

    The aim of this investigation was to develop and test two artificial neural networks (ANN) to apply to physical activity data collected with a commonly used uniaxial accelerometer. The first ANN model estimated physical activity metabolic equivalents (METs), and the second ANN identified activity type. Subjects (n = 24 men and 24 women, mean age = 35 yr) completed a menu of activities that included sedentary, light, moderate, and vigorous intensities, and each activity was performed for 10 mi...

  3. Artificial cytoskeletal structures within enzymatically active bio-inorganic protocells.

    Science.gov (United States)

    Kumar, Ravinash Krishna; Li, Mei; Olof, Sam N; Patil, Avinash J; Mann, Stephen

    2013-02-11

    The fabrication of enzymatically active, semi-permeable bio-inorganic protocells capable of self-assembling a cytoskeletal-like interior and undergoing small-molecule dephosphorylation reactions is described. Reversible disassembly of an amino acid-derived supramolecular hydrogel within the internalized reaction space is used to tune the enzymatic activity of the nanoparticle-bounded inorganic compartments. PMID:23027575

  4. Galaxy Zoo: the effect of bar-driven fuelling on the presence of an active galactic nucleus in disc galaxies

    Science.gov (United States)

    Galloway, Melanie A.; Willett, Kyle W.; Fortson, Lucy F.; Cardamone, Carolin N.; Schawinski, Kevin; Cheung, Edmond; Lintott, Chris J.; Masters, Karen L.; Melvin, Thomas; Simmons, Brooke D.

    2015-04-01

    We study the influence of the presence of a strong bar in disc galaxies which host an active galactic nucleus (AGN). Using data from the Sloan Digital Sky Survey and morphological classifications from the Galaxy Zoo 2 project, we create a volume-limited sample of 19 756 disc galaxies at 0.01 < z < 0.05 which have been visually examined for the presence of a bar. Within this sample, AGN host galaxies have a higher overall percentage of bars (51.8 per cent) than inactive galaxies exhibiting central star formation (37.1 per cent). This difference is primarily due to known effects: that the presence of both AGN and galactic bars is strongly correlated with both the stellar mass and integrated colour of the host galaxy. We control for this effect by examining the difference in AGN fraction between barred and unbarred galaxies in fixed bins of mass and colour. Once this effect is accounted for, there remains a small but statistically significant increase that represents 16 per cent of the average barred AGN fraction. Using the L_{[O III]}/MBH ratio as a measure of AGN strength, we show that barred AGNs do not exhibit stronger accretion than unbarred AGNs at a fixed mass and colour. The data are consistent with a model in which bar-driven fuelling does contribute to the probability of an actively growing black hole, but in which other dynamical mechanisms must contribute to the direct AGN fuelling via smaller, non-axisymmetric perturbations.

  5. Active galactic nuclei at z ~ 1.5: III. Accretion discs and black hole spin

    CERN Document Server

    Capellupo, Daniel M; Lira, Paulina; Trakhtenbrot, Benny; Mejía-Restrepo, Julián

    2016-01-01

    This is the third paper in a series describing the spectroscopic properties of a sample of 39 AGN at $z \\sim 1.5$, selected to cover a large range in black hole mass ($M_{BH}$) and Eddington ratio ($L/L_{Edd}$). In this paper, we continue the analysis of the VLT/X-shooter observations of our sample with the addition of 9 new sources. We use an improved Bayesian procedure, which takes into account intrinsic reddening, and improved $M_{BH}$ estimates, to fit thin accretion disc (AD) models to the observed spectra and constrain the spin parameter ($a_*$) of the central black holes. We can fit 37 out of 39 AGN with the thin AD model, and for those with satisfactory fits, we obtain constraints on the spin parameter of the BHs, with the constraints becoming generally less well defined with decreasing BH mass. Our spin parameter estimates range from $\\sim$$-$0.6 to maximum spin for our sample, and our results are consistent with the "spin-up" scenario of BH spin evolution. We also discuss how the results of our anal...

  6. Active galactic nuclei at z ˜ 1.5: III. Accretion discs and Black Hole Spin

    Science.gov (United States)

    Capellupo, D. M.; Netzer, H.; Lira, P.; Trakhtenbrot, B.; Mejía-Restrepo, J.

    2016-04-01

    This is the third paper in a series describing the spectroscopic properties of a sample of 39 AGN at z ˜ 1.5, selected to cover a large range in black hole mass (MBH) and Eddington ratio (L/LEdd). In this paper, we continue the analysis of the VLT/X-shooter observations of our sample with the addition of 9 new sources. We use an improved Bayesian procedure, which takes into account intrinsic reddening, and improved MBH estimates, to fit thin accretion disc (AD) models to the observed spectra and constrain the spin parameter (a★) of the central black holes. We can fit 37 out of 39 AGN with the thin AD model, and for those with satisfactory fits, we obtain constraints on the spin parameter of the BHs, with the constraints becoming generally less well defined with decreasing BH mass. Our spin parameter estimates range from ˜-0.6 to maximum spin for our sample, and our results are consistent with the "spin-up" scenario of BH spin evolution. We also discuss how the results of our analysis vary with the inclusion of non-simultaneous GALEX photometry in our thin AD fitting. Simultaneous spectra covering the rest-frame optical through far-UV are necessary to definitively test the thin AD theory and obtain the best constraints on the spin parameter.

  7. Active galactic nuclei at z ˜ 1.5 - III. Accretion discs and black hole spin

    Science.gov (United States)

    Capellupo, D. M.; Netzer, H.; Lira, P.; Trakhtenbrot, B.; Mejía-Restrepo, J.

    2016-07-01

    This is the third paper in a series describing the spectroscopic properties of a sample of 39 AGN at z ˜ 1.5, selected to cover a large range in black hole mass (MBH) and Eddington ratio (L/LEdd). In this paper, we continue the analysis of the VLT/X-shooter observations of our sample with the addition of nine new sources. We use an improved Bayesian procedure, which takes into account intrinsic reddening, and improved MBH estimates, to fit thin accretion disc (AD) models to the observed spectra and constrain the spin parameter (a*) of the central black holes. We can fit 37 out of 39 AGN with the thin AD model, and for those with satisfactory fits, we obtain constraints on the spin parameter of the BHs, with the constraints becoming generally less well defined with decreasing BH mass. Our spin parameter estimates range from ˜-0.6 to maximum spin for our sample, and our results are consistent with the `spin-up' scenario of BH spin evolution. We also discuss how the results of our analysis vary with the inclusion of non-simultaneous GALEX photometry in our thin AD fitting. Simultaneous spectra covering the rest-frame optical through far-UV are necessary to definitively test the thin AD theory and obtain the best constraints on the spin parameter.

  8. Artificial cervical disc replacement: range of motion of replacement segment and degeneration of adjacent segments%人工颈椎间盘置换:置换节段活动度及相邻节段退变分析

    Institute of Scientific and Technical Information of China (English)

    陈渲宇; 初冬; 伍骥; 郑超; 黄蓉蓉; 崔玉明; 尚咏; 范恒华; 虞攀峰; 赵旭红

    2015-01-01

    BACKGROUND:In recent years,artificial cervical disc replacement surgery as a new method for the treatment of cervical disease has gradualy been accepted and understood,but relevant complications have gradualy attracted attention.OBJECTIVE:To investigate the clinical outcomes of artificial cervical disc replacement in the treatment of cervical disease and the range of motion of the replacement segment.METHODS: A total of 25 patients with artificial cervical disc replacement in the treatment of cervical spondylosis,who were treated in the Department of Orthopedics,Air Force General Hospital of Chinese PLA from August 2006 to April 2012,were enroled in this study,including 15 males and 10 females,aged 31-76 years,averagely 51.04 years.There were 6 cases of double segments and 19 cases of single segment.They were folowed up for 24 to 93 months.Clinical results were assessed using the Japanese Orthopaedic Association score,cervical dysfunction index and pain visual analog scale scores.Imaging was used to observe range of motion,cervical curvature,heterotopic ossification,and degeneration of adjacent segments.RESULTS AND CONCLUSION:Neurological function in al patients was improved to different degrees.One case suffered from mild heterotopic ossification,but no clinical symptoms were found.No significant difference in range of motion of surgical segment,and range of motion of upper and lower adjacent segments was detected between pre-replacement and final folow-up results (P>0.05).No significant difference in range of motion of C2-C7 was found between pre-replacement and final folow-up results (P>0.05).Japanese Orthopaedic Association score,cervical dysfunction index and pain visual analog scale scores were significantly improved during final folow-up compared with pre-replacement (P<0.05).These results indicated that artificial cervical disc replacement in the treatment of cervical disease can achieve better clinical efficacy,can keep the range of motion of

  9. Optimal Recognition Method of Human Activities Using Artificial Neural Networks

    Directory of Open Access Journals (Sweden)

    Oniga Stefan

    2015-12-01

    Full Text Available The aim of this research is an exhaustive analysis of the various factors that may influence the recognition rate of the human activity using wearable sensors data. We made a total of 1674 simulations on a publically released human activity database by a group of researcher from the University of California at Berkeley. In a previous research, we analyzed the influence of the number of sensors and their placement. In the present research we have examined the influence of the number of sensor nodes, the type of sensor node, preprocessing algorithms, type of classifier and its parameters. The final purpose is to find the optimal setup for best recognition rates with lowest hardware and software costs.

  10. Optimal Recognition Method of Human Activities Using Artificial Neural Networks

    Science.gov (United States)

    Oniga, Stefan; József, Sütő

    2015-12-01

    The aim of this research is an exhaustive analysis of the various factors that may influence the recognition rate of the human activity using wearable sensors data. We made a total of 1674 simulations on a publically released human activity database by a group of researcher from the University of California at Berkeley. In a previous research, we analyzed the influence of the number of sensors and their placement. In the present research we have examined the influence of the number of sensor nodes, the type of sensor node, preprocessing algorithms, type of classifier and its parameters. The final purpose is to find the optimal setup for best recognition rates with lowest hardware and software costs.

  11. The Developing of Meaningful Activity in Artificial Environment

    DEFF Research Database (Denmark)

    Holsbæk, Jonas

    Demographic changes in the EU and the rest of the world, the ageing population is in growth as well as incidence of chronically Illnesses as dementia. Health systems around the world are looking for solutions, which can save manpower and provide quality. One of the trusted solutions for this challenge is...... experience of Flow can be hard to achieve or maintain for people with Dementia due to their loss of skills over time. Objectives: The purpose of this project was to develop a platform that supports People with Dementia in performing physical activity, meaningfulness and the experience of Flow. Method...

  12. Application of Artificial Intelligence to the Prediction of the Antimicrobial Activity of Essential Oils

    OpenAIRE

    Mathieu Daynac; Alvaro Cortes-Cabrera; Prieto, Jose M.

    2015-01-01

    Essential oils (EOs) are vastly used as natural antibiotics in Complementary and Alternative Medicine (CAM). Their intrinsic chemical variability and synergisms/antagonisms between its components make difficult to ensure consistent effects through different batches. Our aim is to evaluate the use of artificial neural networks (ANNs) for the prediction of their antimicrobial activity. Methods. The chemical composition and antimicrobial activity of 49 EOs, extracts, and/or fractions was extract...

  13. Clinical outcome of Bryan artificial cervical disc replacement for the treatment of cervical spondylosis: A midterm follow-up%Bryan人工颈椎间盘置换治疗颈椎病的中期临床随访

    Institute of Scientific and Technical Information of China (English)

    丁琛; 孔清泉; 刘浩; 胡韬; 石锐; 李涛; 洪瑛; 宋跃明; 刘立岷; 曾建成

    2011-01-01

    BACKGROUND: Although the short-term clinical efficacy of Bryan artificial cervical disc replacement is generally acknowledged by most spinal surgeons, the midterm and long term clinical results and complications are still unclear.OBJECTIVE: To summarize midterm term clinical results of Bryan artificial cervical disc replacement for the treatment of cervical spondylosis.METHOD: From November 2004 to December 2007, 34 patients had Bryan cervical disc replacement in Department of Orthopedics, West China Hospital were selected, including 30 cases with single replacement and 4 cases with bi-level replacement. Clinical result was evaluated by SF-36 score, JOA score, and neck/arm pain VAS scores. And the data was collected before surgery and at 7 days, 3, 6, 12, 24, 36 and 48 months after surgery. Neutral lateral and dynamic cervical radiographs were made to measure the flexion-extension range of motion (ROM) of operative segment, adjacent segments and C2-7 segment, the intervertebral height of operative and adjacent segments, and the translation of operative level. The intraoperative and postoperative complications were recorded and analyzed.RESULTS AND CONCLUSION: The neurological symptoms of each patient were alleviated notably. The postoperative SF-36physical component score and SF-36 mental component score, JOA score, NDI score and neck/arm pain VAS scores were significantly improved compared with those of the preoperative (P < 0.05), but no statistical significance were noted between each time point after 3-month follow-up (P > 0.05). Each implanted prosthesis preserved the ROM>2° at each follow-up time point,and no heterotopic ossification or spontaneous fusion was found at the operative segment. At 48-month follow-up,flexion-extension ROM of operative segment and C2-7 segment slightly increased but showed no statistical significance compared with the preoperative counterparts (P > 0.05); ROM of upper and lower adjacent segments also showed no statistical

  14. Proximal caries detection using digital subtraction radiography in the artificial caries activity model

    International Nuclear Information System (INIS)

    The purpose of the experiment was to evaluating the diagnostic ability of dental caries detection using digital subtraction in the artificial caries activity model. Digital radiographs of five teeth with 8 proximal surfaces were obtained by CCD sensor (Kodak RVG 6100 using a size no.2). The digital radiographic images and subtraction images from artificial proximal caries were examined and interpreted. In this study, we proposed novel caries detection method which could diagnose the dental proximal caries from single digital radiographic image. In artificial caries activity model, the range of lesional depth was 572-1,374 μm and the range of lesional area was 36.95-138.52 mm2. The lesional depth and the area were significantly increased with demineralization time (p<0.001). Furthermore, the proximal caries detection using digital subtraction radiography showed high detection rate compared to the proximal caries examination using simple digital radiograph. The results demonstrated that the digital subtraction radiography from single radiographic image of artificial caries was highly efficient in the detection of dental caries compared to the data from simple digital radiograph.

  15. Proximal caries detection using digital subtraction radiography in the artificial caries activity model

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jong Hoon; Lee, Gi Ja; Choi, Sam Jin; Park, Young Ho; Kim, Kyung Soo; Jin, Hyun Seok; Hong, Kyung Won; Oh, Berm Seok; Park, Hun Kuk [Department of Biomedical Engineering, School of Medicine, Kyung Hee University, Seoul (Korea, Republic of); Choi, Yong Suk; Hwang, Eui Hwan [Department of Oral and Maxillofacial Radiology, Institute of Oral Biology, School of Dentistry, Kyung Hee University, Seoul (Korea, Republic of)

    2009-03-15

    The purpose of the experiment was to evaluating the diagnostic ability of dental caries detection using digital subtraction in the artificial caries activity model. Digital radiographs of five teeth with 8 proximal surfaces were obtained by CCD sensor (Kodak RVG 6100 using a size no.2). The digital radiographic images and subtraction images from artificial proximal caries were examined and interpreted. In this study, we proposed novel caries detection method which could diagnose the dental proximal caries from single digital radiographic image. In artificial caries activity model, the range of lesional depth was 572-1,374 {mu}m and the range of lesional area was 36.95-138.52 mm{sup 2}. The lesional depth and the area were significantly increased with demineralization time (p<0.001). Furthermore, the proximal caries detection using digital subtraction radiography showed high detection rate compared to the proximal caries examination using simple digital radiograph. The results demonstrated that the digital subtraction radiography from single radiographic image of artificial caries was highly efficient in the detection of dental caries compared to the data from simple digital radiograph.

  16. 人工腰椎间盘假体位置对活动度的影响%Effect of intervertebral position on range of motion after artificial lumbar total disc replacement and clinical management

    Institute of Scientific and Technical Information of China (English)

    刘艳成; 宁尚龙; 杨强; 夏群; 张继东; 徐宝山; 胡永成; 吉宁; 苗军; 白剑强; 韩岳

    2010-01-01

    Objective To discuss the effect of SB Charité lumbar artificial disc position on intervertebral range of motion(ROM)and clinical management.Methods Between 2004 and 2007, 30 discogenic low back pain patients confirmed by discography underwent 1/2-level total disc replacement (TDR)implantation with 32 prostheses.There were 12 males and 18 females with a mean age of 44 years old (range:28-55).All indexed levels were inserted between L4-S1 involving L4-5(n =9), L5S1(n = 19)and L4-S1(n =2).The clinical outcome was measured by Oswestry disability index(ODI)and visual analogue scale(VAS).Radiographic outcome measures included flexion/extension ROM, restoration of operative level intervertebral disc height, maintenance of disc height at the final follow-up.A technique previously described by McAfee was used to evaluate TDR position in three groups.Paired t test was used to compare the preoperative and postoperative ROM and clinical ODI, VAS scores.Results Twenty-eight patients were followed-up for 24-60 months with an average of 38 months.All the prostheses were solidly immobilized with the vertebral endplate.No disc prosthesis rupture, dislocation, subsidence or heterotopic ossification was observed.Preoperative ODI, VAS back pain and VAS leg pain scores were 70.34 ± 9.21, 7.46 ± 2.65,4.81 ± 2.75;and postoperative corresponding scores 7.65 ± 8.61, 0.68 ± 0.69, 0.35 ± 0.32respectively.The positions of disc prostheses were graded as Group Ⅰ , excellent, n = 17;Group Ⅱ,suboptimal, n = 6;Group Ⅲ, poor, n = 5.Preoperative mean intervertebral flexion/extension ROM (degree)of Group Ⅰ to Group Ⅲ were 9.75 ± 2.80, 10.30 ± 1.20 and 10.08 ± 2.43 respectively.The postoperative mean intervertebral flexion/extension ROM(degree): 6.68 ± 3.83, 4.22 ± 3.51 and 3.48 ± 3.56 respectively.Postoperatively all clinical outcome scores were lower than preoperative ones.Disc height was significantly restored.Mean intervertebral ROM decreased versus preoperative

  17. Herniated lumbar disc

    OpenAIRE

    Jordon, Jo; Konstantinou, Kika; O'Dowd, John

    2011-01-01

    Herniated lumbar disc is a displacement of disc material (nucleus pulposus or annulus fibrosis) beyond the intervertebral disc space. The highest prevalence is among people aged 30 to 50 years, with a male to female ratio of 2:1.

  18. Herniated Lumbar Disc

    Science.gov (United States)

    Herniated Lumbar Disc What is a herniated disc? Nonsurgical treatment Medication and pain management Surgery What can I expect after ... at and just below the waist. A herniated lumbar disc can press on the nerves in the spine ...

  19. A Novel Wearable Sensor-Based Human Activity Recognition Approach Using Artificial Hydrocarbon Networks.

    Science.gov (United States)

    Ponce, Hiram; Martínez-Villaseñor, María de Lourdes; Miralles-Pechuán, Luis

    2016-01-01

    Human activity recognition has gained more interest in several research communities given that understanding user activities and behavior helps to deliver proactive and personalized services. There are many examples of health systems improved by human activity recognition. Nevertheless, the human activity recognition classification process is not an easy task. Different types of noise in wearable sensors data frequently hamper the human activity recognition classification process. In order to develop a successful activity recognition system, it is necessary to use stable and robust machine learning techniques capable of dealing with noisy data. In this paper, we presented the artificial hydrocarbon networks (AHN) technique to the human activity recognition community. Our artificial hydrocarbon networks novel approach is suitable for physical activity recognition, noise tolerance of corrupted data sensors and robust in terms of different issues on data sensors. We proved that the AHN classifier is very competitive for physical activity recognition and is very robust in comparison with other well-known machine learning methods. PMID:27399696

  20. A Novel Wearable Sensor-Based Human Activity Recognition Approach Using Artificial Hydrocarbon Networks

    Science.gov (United States)

    Ponce, Hiram; Martínez-Villaseñor, María de Lourdes; Miralles-Pechuán, Luis

    2016-01-01

    Human activity recognition has gained more interest in several research communities given that understanding user activities and behavior helps to deliver proactive and personalized services. There are many examples of health systems improved by human activity recognition. Nevertheless, the human activity recognition classification process is not an easy task. Different types of noise in wearable sensors data frequently hamper the human activity recognition classification process. In order to develop a successful activity recognition system, it is necessary to use stable and robust machine learning techniques capable of dealing with noisy data. In this paper, we presented the artificial hydrocarbon networks (AHN) technique to the human activity recognition community. Our artificial hydrocarbon networks novel approach is suitable for physical activity recognition, noise tolerance of corrupted data sensors and robust in terms of different issues on data sensors. We proved that the AHN classifier is very competitive for physical activity recognition and is very robust in comparison with other well-known machine learning methods. PMID:27399696

  1. Preliminary clinical outcomes of traumatic cervical herniation by artificial cervical disc replacement%人工椎间盘置换治疗外伤性颈椎椎间盘突出症的初期临床疗效

    Institute of Scientific and Technical Information of China (English)

    欧云生; 刘显宏; 权正学; 唐可; 罗小辑; 蒋电明; 安洪

    2011-01-01

    Objective To observe the preliminary outcomes of traumatic cervical hemiation treated by artificial cervical disc replacement (ACDR). Methods Clinical data of 8 patients with traumatic cervical hemiation undergoing ACDR from April 2007 to February 2011 were studied retrospectively. All the patients were assessed by clinical observation and radiological studies preoperatively, in 3 and 6 months postoperatively, and at the end of follow-up. Clinical outcome was evaluated using Japanese Orthopaedic Association (JOA) score, neck disabiliy index (NDI) criteria, and visual analog scale (VAS). Functional spinal unit range of motion (ROM) was also measured in the reontgenographs at anteroposterior and lateral, bending and extending positions. Results All cases were followed up for 6-36 months (mean 15 months). The JOA, NDI, VAS ( neck pain and arm pain) and cervical unit ROM were all significantly improved after operation ( P <0.05). No neurological or vascular complication was found in these 8 cases. The disc height and stability of cervical vertebra were maintained in the reontgenographs taken at the final follow-up. One case was found having artificial cervical prosthesis antedisplacement 1 mm 42 d after operation, and the distance of antedisplacement was not increased at the final follow-up. There was no subsidence, loosening, excursion, or heterotopic ossification in the other 7 patients. Conclusion As long as indication is correctly chosen, satisfactory outcomes will be achieved for traumatic cervical hemiation by ACDR.%目的 观察人工颈椎椎间盘置换术(artificial cervical disc replacement,ACDR)治疗外伤性颈椎椎间盘突出症的初期临床疗效.方法 对8例行ACDR的外伤性颈椎椎间盘突出症患者的临床资料进行随访分析.临床疗效评价包括术前、术后3个月、术后6个月及末次随访时的日本骨科学会(Japanese Orthopaedic Association,JOA)评分、颈椎功能障碍指数( neck disabiliy index,NDI)评分

  2. Curative effect evaluation and complication analysis of Bryan artificial cervical disc replacement%Bryan人工颈椎间盘置换术后疗效评价及并发症分析

    Institute of Scientific and Technical Information of China (English)

    蓝旭; 许建中; 刘雪梅; 葛宝丰

    2013-01-01

    To observe the curative effects and complications nf Bryan cervical disc replacement for cervical disc herniation. Methods:From Jannary 2005 to December 2008,39 patients with cervical disc herniation were treated with Bryan cervical disc replacement. There were 20 males and 19 females,with an average age of 47 years old (ranged ,35 to 59). Spinal compression symptom (20 cases) and nerve root symptom (19 eases) were main clinical symptoms. Single level disc was replaced in 35 cases and two-level replaced in 4 cases. Offset and activity of prosthesis, cervical physiological curvature, heterotopic ossification, prosthetic fusion were observed by dynamic X-ray. According to Odom's standard and JOA score, nerve function were evaluated;and depending on NDI standard,clinical symptom and daily function status were recorded. Results: All the patients were followed up from 16 to 36 months with an average of 24 months. Nerve function obviously improved and radiating pain of upper limb completely relieved. No patient with prosthetic anterior-posterior offset more than 2 mm was found. Prosthetic flexion and extention angle was(8.5±1.8)°,left and right flexion range respectively were (3.5±1.2)° and (3.3±1.5)°. Cervical physiological curvature improved obviously or recovered normally. Three cases occurred in heterotopic ossification and 2 cases occurred in prosthetic fusion. According to Odom's standard,25 cases got an excellent results,9 good,5 fair,the rate of excellent and good was 87.2%. JOA score increased from preoperative(8.26±1.32) to (15.71±1.89) at final follow-up and NDI decreased from preoperative (43.7±3.8) to (20.1±2.9) at final follow-up. Conclusion: Treatment of cervical disc herniation with Bryan cervical disc replacement can get the good curative effects,which can obtain good nerve functional recovery,cervical stability and activity. Nevertheless, the operation has typical complication such as heterotopic ossification and prosthetic fusion. Thus.it is

  3. Gene expression of fibrinolytic factors urokinase plasminogen activator and plasminogen activator inhibitor-1 in rabbit temporo-mandibular joint cartilage with disc displacement

    Institute of Scientific and Technical Information of China (English)

    ZHAN Jing; GU Zhi-yuan; WU Li-qun; ZHANG Yin-kai; HU Ji-an

    2005-01-01

    Background The urokinase plasminogen activator system is believed to play an important role in degradation of the extracellular matrix associated with cartilage and bone destruction; however its precise roles in temporomandibular disorders have not yet been clarified. The aims of this study were to investigate the gene expression of fibrinolytic factors urokinase plasminogen activator (uPA) and plasminogen activator inhibitor-1 (PAI-1) in the articular cartilage of rabbit temporomandibular joint (TMJ) with disc displacement (DD) and to probe the relationship between fibrinolytic activity and cartilage remodeling. Methods Disc displacement of right joints was performed in 36 of 78 rabbits under investigation. The animals were sacrificed at 4 days and 1, 2, 4, 8 and 12 weeks after surgery, respectively. The right joints of these animals were harvested and processed for the examination of mRNA expression of uPA and PAI-1 in articular cartilage using in situ hybridization techniques. Results The expression of uPA and PAI-1 was co-expressed weakly in the chondrocytes from transitive zone to hypertrophic zone and mineralized zone, while no hybridizing signals were shown in proliferative zone and superficial zone in control rabbits. The most striking was the up-regulation of uPA and PAI-1 mRNA in 4-day rabbits postoperatively at the onset of cartilage degeneration. The strongest hybridizing signals for uPA and PAI-1 were seen in 2-week rabbits postoperatively. After 2 weeks, the expression of uPA and PAI-1 began to decrease and reached nearly normal level at 12 weeks. Conclusions The expression of the uPA/PAI-1 system coincides with the pathological changes in condylar cartilage after DD. The uPA/PAI-1 system may be one of the essential mediators in articular cartilage remodeling.

  4. Spine imaging after lumbar disc replacement: pitfalls and current recommendations

    OpenAIRE

    Sandén Bengt; Robinson Yohan

    2009-01-01

    Abstract Background Most lumbar artificial discs are still composed of stainless steel alloys, which prevents adequate postoperative diagnostic imaging of the operated region when using magnetic resonance imaging (MRI). Thus patients with postoperative radicular symptoms or claudication after stainless steel implants often require alternative diagnostic procedures. Methods Possible complications of lumbar total disc replacement (TDR) are reviewed from the available literature and imaging reco...

  5. Broken discs: warp propagation in accretion discs

    Science.gov (United States)

    Nixon, Christopher J.; King, Andrew R.

    2012-04-01

    We simulate the viscous evolution of an accretion disc around a spinning black hole. In general, any such disc is misaligned, and warped by the Lense-Thirring effect. Unlike previous studies, we use effective viscosities constrained to be consistent with the internal fluid dynamics of the disc. We find that non-linear fluid effects, which reduce the effective viscosities in warped regions, can promote breaking of the disc into two distinct planes. This occurs when the Shakura & Sunyaev dimensionless viscosity parameter α is ≲0.3 and the initial angle of misalignment between the disc and hole is ≳45°. The break can be a long-lived feature, propagating outwards in the disc on the usual alignment time-scale, after which the disc is fully co-aligned or counter-aligned with the hole. Such a break in the disc may be significant in systems where we know the inclination of the outer accretion disc to the line of sight, such as some X-ray binaries: the inner disc, and so any jets, may be noticeably misaligned with respect to the orbital plane.

  6. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... are your thoughts on that? Well, the more athletic they are, the more I’m going to ... three weeks, and people are back to doing sports like. Now golf is not a very high- ...

  7. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... the patients do so well right off the bat, you know, a little trouble swallowing maybe. I ... operations because they feel well right off the bat. So I’m taking out these pins. I ...

  8. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... play tennis? When I can do things recreationally?” What are your thoughts on that? Well, the more athletic they ... near future of the state of the art. What are your thoughts on that, Bill? I really think this ...

  9. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... Harrisburg, PA Welcome to this “OR Live” webcast presentation brought to you by Pinnacle Health in Harrisburg, ... Thank you for watching this “OR Live” webcast presentation brought to you by Pinnacle Health in Harrisburg, ...

  10. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... Beutler is defining out, that’s the platysma muscle right there. He’ll divide that a little to ... catch on that a little bit different. But right now Dr. Beutler is exposing the spine. He’s ...

  11. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... actually doing an operation like this. But by far and away, the most common problem that you ... technical aspect of putting the implant in is far greater than just putting in a piece of ...

  12. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... to learn more. Just click on the “Request information” button on your screen and open the door ... to learn more, just click on the “Request information” button on your webcast screen and open the ...

  13. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... and tingling in the hands and loss of motor strength. Is that typical of how this patient ... that’s where the problem is. That’s where we start getting patients that have a pinched nerve or ...

  14. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... which is kind of connective tissue that helps hold things together. It’s the very last layer before ... and allows the vertebrae to lock on or hold the implant tight so it has a good ...

  15. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... pressure off that nerve. So a lot of times these patients present with significant pain not only ... so it doesn’t wiggle out. There are times during this operation we’re going to pushing ...

  16. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... are relatively fragile structures, and I want to protect them as best I can. So we just ... end plates and secure his position. That’s great, Bill. That does look good. Obviously this new technology ...

  17. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... technically there’s sometimes a bit more of a challenge to it because you’re putting something that’s ... Well it’s not something you learn in med school. This is on operation kind that takes ... First, the primary chisel is inserted over the trial and advanced ...

  18. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... everybody in the operating room today. And our staff here has really worked hard to make this ... I want to thank Dr. Beutler and his staff for helping out with a successful procedure. I’ ...

  19. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... biting instrument and remove that. He has a large bone spur right here. This piece of bone ... is exiting right there, and there was a large piece of bone. We were fighting it as ...

  20. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... like. Now golf is not a very high-impact game, but there’s a lot of bending, and ... extremely well. And, again, this is, I think, technology on the forefront that will become the state- ...

  1. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... esophagus and the trachea because they are relatively fragile structures, and I want to protect them as ... an investigational group that was in the United States. There were 20 centers in the United States ...

  2. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... like that. I sometimes tell people it’s crab meat. Do you do that, Walt? Yeah, I do. ... what you said, kind of looks like crab meat when it sticks back. And so what happens ...

  3. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... want to put these in, so patients with osteoporosis or, you know, very, very severe stenosis. What ... this. As you said, if a person has osteoporosis and the bones are thin, or if a ...

  4. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... where I have this awl. This is just something sharp so I can get a screw started ... down here. I’m just getting a little something started there. All right. So what we’re ...

  5. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... Well it’s not something you learn in med school. This is on operation kind that takes experience, ... three weeks, and people are back to doing sports like. Now golf is not a very high- ...

  6. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... at the fascia, which is kind of connective tissue that helps hold things together. It’s the very ... the spine itself. That’s this kind of whitish tissue. Rather than cutting it, I’m just actually ...

  7. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... little smaller one, and this is that sizing business. So what I’m going to look at ... minimally invasive this procedure is. It’s such a small incision and such carpentry that can be done ...

  8. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... he is goes to do is stick a screw into the bottom part of C6 and into ... just something sharp so I can get a screw started and we’ll put a screw in right there, and we’re going to ...

  9. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... little to give him a little more visual aspect, and then he’ll find this sternocleidomastoid. Now ... part to heal. And the third and final aspect that he’s going to do is actually insert ...

  10. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... neck out you can actually make out the definition of that muscle. He will split that muscle ... is an operation that I think will become standard, and state of the art. Right now we’ ...

  11. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... and releasing pressure on the surrounding nerves and spinal cord. We’re going to do an image right ... so he can fully and thoroughly decompress the spinal cord exist. So he is right now working his ...

  12. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... cord. So it’s sometimes a little bit more work. Well, there’s the space for where that nerve ... end plate forms the socket. The implant components work together with the surrounding spinal structures to provide ...

  13. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... Yeah. They look -- the screws look good just looking at the fluoro image there. Why don’t ... incision. Well, it is. You know I guess looking at my thumbs, you can see that the ...

  14. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... in there, but we’re able to avoid these with our dissection, and you’ll see that ... than cutting it, I’m just actually using these cotton balls to push them apart gently, and ...

  15. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... the near future of the state of the art. What are your thoughts on that, Bill? I ... think will become standard, and state of the art. Right now we’re following these patients out ...

  16. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... of the neck. There are some vital anatomic structures in there, but we’re able to avoid these with our ... make any difference. There aren’t really any structures that it would harm in any way. But when it does it in the back of ...

  17. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... a small incision and such carpentry that can be done through a one, one-and-a-half-inch incision. Well, it is. You know I guess looking at ... could go more anterior, but it seems to be recessed. Do you think more anterior? No. Ideally that should work. Well that’s right on the border now. Yeah. Well ...

  18. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... Beutler planned the incision with the use of X-Ray, placing a marker external to the skin to ... he wants to do is confirm it with X-Ray so that there’s no confusion to take the ...

  19. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... screen and open the door to informed medical care. OR Live, the vision of improving health. Hi, ... screen and open the door to informed medical care. “OR Live,” the vision of improving health. 11

  20. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... have to mess with those today or any day. So can I have the nerve fork. I’ ... not to go to work for about ten days. I must say this patient here, he is ... that allow patients to go home the same day after these operations because they feel well right ...

  1. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... screen and open the door to informed medical care. OR Live, the vision of improving health. Hi, my name is Walt Peppelman, and welcome. ... screen and open the door to informed medical care. “OR Live,” the vision of improving health. 11

  2. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... Live” webcast presentation brought to you by Pinnacle Health in Harrisburg, Pennsylvania. “OR Live” makes it easy ... medical care. OR Live, the vision of improving health. Hi, my name is Walt Peppelman, and welcome. ...

  3. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... through a notch and allows the vertebrae to lock on or hold the implant tight so it ... doing now, this is a holding pin. This locks this jig into the vertebral body and allows ...

  4. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... socket implant that is composed of two cobalt chrome alloy end plates and a polyethylene insert. The ... is an operation that I think will become standard, and state of the art. Right now we’ ...

  5. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... your screen and open the door to informed medical care. OR Live, the vision of improving health. ... small piece of what we call -- it’s a medical plastic. It’s ultrahigh molecular weight polyethylene, and it’s ...

  6. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... is go through skin and down through the muscle that he was explaining called the “platysma muscle.” This is a very small muscle, very thin, and actually as you stretch your ...

  7. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... welcome. Today we’re going to have the opportunity to watch Dr. William Beutler perform a total ... of the nerve. So that’s what Dr. Beutler’s job is right now, is to remove all this ...

  8. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... incorporates this implant pretty quickly. Boy, that’s a good point. You know, folks would worry about where does this ... device, but you don’t even need that. You put that in there so good the first time, I don’t even think ...

  9. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... of the neck. There are some vital anatomic structures in there, but we’re able to avoid ... and the trachea because they are relatively fragile structures, and I want to protect them as best ...

  10. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... door to informed medical care. OR Live, the vision of improving health. Hi, my name is Walt ... door to informed medical care. “OR Live,” the vision of improving health. 11

  11. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... quite the opposite. It’s a very, very high success-rate operation. The clinical results and the FDA ... in the way of problems, and long-term success seems to be holding, so I’m very, ...

  12. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... first thing he will do is go through skin and down through the muscle that he was ... X-Ray, placing a marker external to the skin to help to delineate the exact trajectory into ...

  13. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... neck out you can actually make out the definition of that muscle. He will split that muscle ... Beutler is defining out, that’s the platysma muscle right there. He’ll divide that a little to ...

  14. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... Pinnacle Health in Harrisburg, Pennsylvania. “OR Live” makes it easy for you to learn more. Just click ... blood loss with this procedures and this approach. It’s actually a very dry procedure, and he’ll ...

  15. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... It has an outer rim of what we call the “annulus fibrosus.” And then the inside is ... the canal and explore out into what we call the foraminal region to make sure there’s no ...

  16. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... he will do is measure and get a trial implant. This implant will be approximately the size ... to be inserted at. After he places a trial and he’s happy with that, the next thing ...

  17. Artificial Cervical Disc Replacement Improves Mobility

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    Full Text Available ... been utilized to perform anterior cervical discectomies and fusions. The fusion procedure has been the most common way to ... significant benefits over the previous procedure of the fusion, and that is, able to maintain motion of ...

  18. In vitro fertilization and artificial activation of eggs of the direct-developing anuran Eleutherodactylus coqui

    Directory of Open Access Journals (Sweden)

    Toro Esteban

    2004-08-01

    Full Text Available Abstract Although much is known about the reproductive biology of pond-breeding frogs, there is comparatively little information about terrestrial-breeding anurans, a highly successful and diverse group. This study investigates the activation and in vitro fertilization of eggs of the Puerto Rican coqui frog obtained by hormonally induced ovulation. We report that spontaneous activation occurs in 34% of eggs, probably in response to mechanical stress during oviposition. Artificial activation, as evidenced by the slow block to polyspermy and the onset of zygote division, was elicited both by mechanical stimulation and calcium ionophore exposure in 64% and 83% of the cases, respectively. Finally, one in vitro fertilization protocol showed a 27% success rate, despite the fact that about one third of all unfertilized eggs obtained by hormone injection auto-activate. We expect these findings to aid in the conservation effort of Eleutherodactylus frogs, the largest vertebrate genus.

  19. Chewing insect predation on artificial caterpillars is related to activity density of ground beetles (Coleoptera: Carabidae)

    DEFF Research Database (Denmark)

    Ferrante, M.; Lövei, G. L.

    2015-01-01

    In cultivated landscapes, predatory arthropods play an important role for pest control. Traditionally, monitoring their effect on pests was done using indirect measures (e.g. characterising predator activity by the numbers of predators caught). However, the contribution of predators to predation is...... traps in winter wheat (Triticum aestivum). Forty-six percent (n=756/1637) of the artificial sentinel prey were attacked after 24 h, mostly by chewing insects (88%, n=665/756), and 1102 carabids with a size of ≥15mm were collected. Ground beetles were also the most common predatory group, followed by...

  20. Lumbar disc replacement in adolescents: An initial experience in two cases

    OpenAIRE

    Kasliwal, Manish K.; Harel Deutsch

    2012-01-01

    Management of painful lumbar disc degeneration is one of the most common conditions treated by spine surgeons. Several recent prospective multicenter trials have demonstrated the effectiveness of artificial lumbar disc replacement in treating discogenic lower back pain. Though data on the safety and effectiveness has gradually been accumulated in adults, there is a lack of published data on the effectiveness and feasibility of lumbar artificial disc replacement in adolescents. The authors sha...

  1. Analysis of mid-long term clinical efficacy and complications of Bryan artificial cervical disc replacement%Bryan人工颈椎椎间盘置换术后中长期临床疗效及相关问题分析

    Institute of Scientific and Technical Information of China (English)

    蒋涛; 任先军; 王卫东; 初同伟; 李长青

    2011-01-01

    目的 探讨Bryan人工颈椎椎间盘置换术(artificial cervical disc replacement,ACDR)治疗颈椎椎间盘突出症的中长期临床疗效及并发症发生情况.方法 回顾分析13例颈椎椎间盘突出症患者,采用Bryan ACDR治疗,单节段11例,双节段2例,共置换了15个节段.术后定期随访,依照Odom评级和日本骨科学会(Japanese Orthopaedic Association,JOA)评分评定临床疗效和神经功能改善情况,通过影像学资料观察假体位移、假体周围骨吸收、异位骨化、假体活动度及颈椎生理曲度变化.结果 经过5年以上的随访,患者神经症状有明显缓解,Odom评级临床优良率达到92.3%,JOA评分由术前的11.6分增加到的15.6分.术后X线片示假体稳定,没有出现假体前后位移>2mm.术后1例出现自发性融合;1例在置换节段上位椎体前下缘有明显骨吸收,接近2.5mm,并伴椎体后缘的异位骨化.末次随访时置换假体活动度平均为9.2°,邻近节段活动度与术前相当.结论 通过5~7年的中长期随访,Bryan ACDR术治疗颈椎椎间盘突出症具有较好的临床疗效,并发症少,安全可靠.%Objective To evaluate the mid-long term clinical efficacy and complications of Bryan artificial cervical arthro-plasty replacement (ACDR) for treatment of cervical disc herniation. Methods Thirteen cases of cervical disc herniation were retrospectively analyzed. A total of 15 sets of Bryan cervical disc prosthesis were implanted into 13 cases, including single level disc replacement in 11 cases and bi-level in 2 cases. During follow-up, the clinical efficacy and neurological function were evaluated by Odom's criteria and Japanese Orthopaedic Association (JOA)score; the mobility, resorption, heteropic ossification, physiological lordosis and range of motion of the implanted and adjacent segment were observed on dynamic radiograph. Results After more than 5 years of follow-up, all cases showed significant improvement in neurological

  2. Artificial neural network and multiple regression model for nickel(II) adsorption on powdered activated carbons.

    Science.gov (United States)

    Hema, M; Srinivasan, K

    2011-07-01

    Nickel removal efficiency of powered activated carbons of coconut oilcake, neem oilcake and commercial carbon was investigated by using artificial neural network. The effective parameters for the removal of nickel (%R) by adsorption process, which included the pH, contact time (T), distinctiveness of activated carbon (Cn), amount of activated carbon (Cw) and initial concentration of nickel (Co) were investigated. Levenberg-Marquardt (LM) Back-propagation algorithm is used to train the network. The network topology was optimized by varying number of hidden layer and number of neurons in hidden layer. The model was developed in terms of training; validation and testing of experimental data, the test subsets that each of them contains 60%, 20% and 20% of total experimental data, respectively. Multiple regression equation was developed for nickel adsorption system and the output was compared with both simulated and experimental outputs. Standard deviation (SD) with respect to experimental output was quite higher in the case of regression model when compared with ANN model. The obtained experimental data best fitted with the artificial neural network. PMID:23029923

  3. p38 mitogen-activated protein kinase inhibition modulates nucleus pulposus cell apoptosis in spontaneous resorption of herniated intervertebral discs: An experimental study in rats.

    Science.gov (United States)

    Zhu, Yu; Liu, Jin-Tao; Yang, Li-Yan; Du, Wen-Pei; Li, Xiao-Chun; Qian, Xiang; Yu, Peng-Fei; Liu, Jian-Wen; Jiang, Hong

    2016-05-01

    The present study was performed to investigate the role of p38 mitogen‑activated protein kinase (MAPK) in the resorption of herniated intervertebral discs in 30 rats. In the non‑contained and p38 MAPK inhibition (p38i) groups, two coccygeal intervertebral discs (IVDs) were removed and wounded prior to relocation into the subcutaneous space of the skin of the back. In the contained group, the cartilage endplates maintained their integrity. Furthermore, SB203580 was injected intraperitoneally into the p38i group, whereas saline was injected into the other two groups. In the non‑contained group, the weight of the relocated IVDs decreased to a greater extent over time when compared with the contained and p38i groups. Phosphorylated p38, tumor necrosis factor‑α, and interleukin‑1β were observed to exhibit higher expression levels in the non‑contained group compared with the contained and p38i groups, at weeks 1 and 4 post‑surgery. The expression level of caspase‑3 and the densities of apoptotic disc cells were significantly higher in the non‑contained group compared with the contained and p38i groups at 4 weeks post‑surgery. In conclusion, p38 MAPK induces apoptosis in IVDs, while also accelerating the resorption of the relocated IVDs. Thus, p38 MAPK may be important in spontaneous resorption of IVDs. PMID:27035219

  4. Urea elimination using a cold activated-carbon artificial tubulus for hemofiltration.

    Science.gov (United States)

    Lehmann, H D; Marten, R; Fahrner, I; Gullberg, C A

    1981-11-01

    Urea adsorption on active carbon is reversible and temperature-dependent. Urea adsorption isotherms of different carbons were determined at 0 degrees C and 65 degrees C within the equilibrium concentration range of 1.0-3.4 gm/L. At low urea concentrations considerable differences (3.4-13.0 gm/kg carbon at concentrations of 1.0 gm/L) were found between different types of activated carbon. The overall internal surface area was of minor importance compared to the pore size distribution. Adsorbing at low temperature, desorbing at high temperature, and flushing the carbon adsorber with a limited volume of the liquid to be purified yielded an "artificial urine." Compared to the original urea concentration of the filtrate, this "artificial urine" had an increased urea concentration. From a 36-liter volume containing 90 grams urea dissolved in saline, 18 liters were recirculated at a flow rate of 100 ml/min. The influence of adsorption and desorption time intervals was evaluated. After one to one and a half hours the carbon was saturated with urea. After saturation, about 1.4 grams urea were eliminated per cycle. In the "artificial urine" urea concentrations of up to 4.5 gm/L were found when the original solution contained only 2.5 gm/L. In the "patient" volume the urea concentration decreased from 2.5 gm/L to 1.9-2.1 gm/L. Within three hours a total of 22 grams of urea was removed by 3 x 120 grams activated carbon corresponding to removal of 50% of the urea passing the "artificial tubulus." The advantage of this system is that after priming, no additional physiological solution would be necessary. The necessity of excessive safety controls, additional electrolyte adjustment, energy demand in the form of direct current, and great amounts of waste in solid form lead to the conclusion that for intermittent hemofiltration treatment, commercially produced and controlled infusion solution is preferable. PMID:7325876

  5. Prodisc-C人工颈椎椎间盘置换的临床疗效观察和运动功能评估%Clinical efficiency and motor function assessment of Prodisc-C artificial cervical disc replacement

    Institute of Scientific and Technical Information of China (English)

    陈道森; 施荣茂; 周强; 罗飞; 代飞; 张劲松; 许建中

    2011-01-01

    目的 通过术后随访评价Prodisc-C人工颈椎椎间盘置换术(artificial cervical disc replacement,ACDR)治疗颈椎病的临床疗效及其对颈椎置换节段、邻近节段运动功能的影响.方法 回顾性分析2009年8月~2011年2月行Prodisc-C ACDR治疗20例颈椎病患者,其中脊髓型9例、神经根型8例、混合型3例,单椎间盘置换17例、双椎间盘置换3例.患者术前行CT、MRI检查明确诊断,术前和术后定期行疼痛视觉模拟量表(visual analogue scale,VAS)和日本骨科学会(Japanese Orthopaedic Association,JOA)及摄颈椎X线片.结果 13例患者获得6~18个月随访.患者术前颈肩背疼痛、上下肢麻木、肌力减弱等不适症状均明显改善.术后VAS及JOA评分均较术前明显改善,差异有统计学意义(P<0.01);置换节段椎间活动度( range of motion,ROM)在术后1、3、6个月显著增大,与术前相比差异有统计学意义(P<0.01);在末次随访时仍大于术前,差异有统计学意义(P<0.05);上下位邻近节段椎间隙高度和椎间ROM与术前相比,差异无统计学意义(P>0.05).所有病例未见假体松动、移位和异位骨化.结论 Prodisc-C ACDR短期随访疗效优良,置换节段ROM增大,邻近节段椎间隙高度和椎间ROM维持在正常水平,但远期疗效还有待进一步随访观察.%Objective To evaluate the clinical efficacy of artificial cervical disc replacement (ACDR) with Prodisc-C and its effects on the motor function of the replaced level and adjacent segments. Methods A total of 20 patients who received ACDR with Prodisc-C from April 2009 to February 2011 were retrospectively analyzed. There were 9 patients with myelopathy, 8 with radiculopa-thy, and the left 3 with both symptoms. There were 17 participators received single level replacement, and the other 3 had 2 levels replaced. All the patients received CT and MRI preoperatively for accurate diagnosis. Visual analogue scale ( VAS) scores for neck and arm

  6. INJURIES IN DISC GOLF - A DESCRIPTIVE CROSS-SECTIONAL STUDY

    DEFF Research Database (Denmark)

    Rahbek, Martin Amadeus; Nielsen, Rasmus Oestergaard

    2016-01-01

    social media, and around disc-golf courses in Denmark. The questionnaire included questions regarding disc-golf participation and the characteristics of injuries acquired through disc golf participation. The data was analyzed descriptively. RESULTS: An injury prevalence of 13.3% (95% CI: 6.7% to 19......BACKGROUND: Disc golf is rapidly increasing in popularity and more than two million people are estimated to regularly participate in disc golf activities. Despite this popularity, the epidemiology of injuries in disc golf remains under reported. PURPOSE: The purpose of the present study was to...... investigate the prevalence and anatomic distribution of injuries acquired through disc-golf participation in Danish disc golf players. METHODS: The study was a cross-sectional study conducted on Danish disc-golf players. In May 2015, invitations to complete a web-based questionnaire were spread online via...

  7. Active Path Selection of Fluid Microcapsules in Artificial Blood Vessel by Acoustic Radiation Force

    Science.gov (United States)

    Masuda, Kohji; Muramatsu, Yusuke; Ueda, Sawami; Nakamoto, Ryusuke; Nakayashiki, Yusuke; Ishihara, Ken

    2009-07-01

    Micrometer-sized microcapsules collapse upon exposure to ultrasound. Use of this phenomenon for a drug delivery system (DDS), not only for local delivery of medication but also for gene therapy, should be possible. However, enhancing the efficiency of medication is limited because capsules in suspension diffuse in the human body after injection, since the motion of capsules in blood flow cannot be controlled. To control the behavior of microcapsules, acoustic radiation force was introduced. We detected local changes in microcapsule density by producing acoustic radiation force in an artificial blood vessel. Furthermore, we theoretically estimated the conditions required for active path selection of capsules at a bifurcation point in the artificial blood vessel. We observed the difference in capsule density at both in the bifurcation point and in alternative paths downstream of the bifurcation point for different acoustic radiation forces. Comparing the experimental results with those obtained theoretically, the conditions for active path selection were calculated from the acoustic radiation force and fluid resistance of the capsules. The possibility of controlling capsule flow towards a specific point in a blood vessel was demonstrated.

  8. Active Vibration Control of the Smart Plate Using Artificial Neural Network Controller

    Directory of Open Access Journals (Sweden)

    Mohit

    2015-01-01

    Full Text Available The active vibration control (AVC of a rectangular plate with single input and single output approach is investigated using artificial neural network. The cantilever plate of finite length, breadth, and thickness having piezoelectric patches as sensors/actuators fixed at the upper and lower surface of the metal plate is considered for examination. The finite element model of the cantilever plate is utilized to formulate the whole strategy. The compact RIO and MATLAB simulation software are exercised to get the appropriate results. The cantilever plate is subjected to impulse input and uniform white noise disturbance. The neural network is trained offline and tuned with LQR controller. The various training algorithms to tune the neural network are exercised. The best efficient algorithm is finally considered to tune the neural network controller designed for active vibration control of the smart plate.

  9. Anti-glycated activity prediction of polysaccharides from two guava fruits using artificial neural networks.

    Science.gov (United States)

    Yan, Chunyan; Lee, Jinsheng; Kong, Fansheng; Zhang, Dezhi

    2013-10-15

    High-efficiency ultrasonic treatment was used to extract the polysaccharides of Psidium guajava (PPG) and Psidium littorale (PPL). The aims of this study were to compare polysaccharide activities from these two guavas, as well as to investigate the relationship between ultrasonic conditions and anti-glycated activity. A mathematical model of anti-glycated activity was constructed with the artificial neural network (ANN) toolbox of MATLAB software. Response surface plots showed the correlation between ultrasonic conditions and bioactivity. The optimal ultrasonic conditions of PPL for the highest anti-glycated activity were predicted to be 256 W, 60 °C, and 12 min, and the predicted activity was 42.2%. The predicted highest anti-glycated activity of PPG was 27.2% under its optimal predicted ultrasonic condition. The experimental result showed that PPG and PPL possessed anti-glycated and antioxidant activities, and those of PPL were greater. The experimental data also indicated that ANN had good prediction and optimization capability. PMID:23987324

  10. Activity patterns during food provisioning are affected by artificial light in free living great tits (Parus major.

    Directory of Open Access Journals (Sweden)

    Mieke Titulaer

    Full Text Available Artificial light may have severe ecological consequences but there is limited experimental work to assess these consequences. We carried out an experimental study on a wild population of great tits (Parus major to assess the impact of light pollution on daily activity patterns during the chick provisioning period. Pairs that were provided with a small light outside their nest box did not alter the onset, cessation or duration of their working day. There was however a clear effect of artificial light on the feeding rate in the second half of the nestling period: when provided with artificial light females increased their feeding rate when the nestlings were between 9 and 16 days old. Artificial light is hypothesised to have affected the perceived photoperiod of either the parents or the offspring which in turn led to increased parental care. This may have negative fitness consequences for the parents, and light pollution may thus create an ecological trap for breeding birds.

  11. Experimental and clinical studies on dynamic circulation of intervertebral discs by radiation clearance method

    International Nuclear Information System (INIS)

    Few studies on the mechanism of dynamic circulation in intervertebral discs are reported. The purpose of this study is to clarify the dynamic mechanism of circulation in the lumbar intervertebra discs with radioisotope clearance, experimentally and clinically. Rabbits were used as experimental animals and were divided into two groups, normal and artificially injured. I131-sodium was injected into them and the clearance was followed. Injected I131-sodium was cleared in the order of; 1) discs with injured annulus fibrosus, 2) discs with injection of α-chymotrypsin, 3) discs with injuries in the border between vertebral body and annulus fibrosus, 4) and normal discs. Human degenerated discs were also used for this study. In the clinical cases, I131-sodium was cleared faster in the degenerated discs than in the normal. The pathway for I131-sodium to be cleared is supposed to be extravascular and interstitial spaces in the disc. (author)

  12. Data Fusion Using Different Activation Functions in Artificial Neural Networks for Vehicular Navigation

    Directory of Open Access Journals (Sweden)

    MALLESWARAN M,

    2010-12-01

    Full Text Available Global positioning System (GPS and Inertial Navigation System (INS data can be integrated together to provide a reliable navigation. GPS/INS data integration provides reliable navigation solutions by overcoming each of their shortcomings, including signal blockage for GPS and increase in position errors with time for INS. This paper aims to provide GPS/INS data integration utilizing Artificial Neural Network (ANN architecture. This architecture is based on Feed Forward Neural Networks, which generally includes Radial Basis Function (RBF neural network and Back Propagation neural network (BPN. These are systematic methods for training multi-layer artificial networks. The BPN-ANN and RBF-ANN modules are trained to predict the INS position error and provide accurate positioning of the moving vehicle. This paper also compares performance of theGPS/INS data integration system by using different activation function like Bipolar Sigmoidal Function (BPSF, Binary Sigmoidal Function (BISF, Hyperbolic Tangential Function (HTF and Gaussian Function (GF in BPN-ANN and using Gaussian function in RBF-ANN.

  13. Crocin exerts anti-inflammatory and anti-catabolic effects on rat intervertebral discs by suppressing the activation of JNK

    OpenAIRE

    Li, Kang; Li, Yan; MA, ZHENJIANG; Zhao, Jie

    2015-01-01

    As intervertebral disc (IVD) degeneration has been proven to contribute to low back pain (LBP), drug treatment aiming at attenuating IVD degeneration may prove to be benefiical. Crocin, a bioactive component of saffron, has been found to exert anti-inflammatory effects on cartilage. In the present study, the anti-inflammatory and anti-catabolic effects of crocin on rat IVDs were analyzed in vitro and ex vivo. Nucleus pulposus (NP) cells were isolated from the lumbar IVDs of Sprague-Dawley rat...

  14. Hydrodynamic instability in warped astrophysical discs

    CERN Document Server

    Ogilvie, Gordon I

    2013-01-01

    Warped astrophysical discs are usually treated as laminar viscous flows, which have anomalous properties when the disc is nearly Keplerian and the viscosity is small: fast horizontal shearing motions and large torques are generated, which cause the warp to evolve rapidly, in some cases at a rate that is inversely proportional to the viscosity. However, these flows are often subject to a linear hydrodynamic instability, which may produce small-scale turbulence and modify the large-scale dynamics of the disc. We use a warped shearing sheet to compute the oscillatory laminar flows in a warped disc and to analyse their linear stability by the Floquet method. We find widespread hydrodynamic instability deriving from the parametric resonance of inertial waves. Even very small, unobservable warps in nearly Keplerian discs of low viscosity can be expected to generate hydrodynamic turbulence, or at least wave activity, by this mechanism.

  15. Artificial Warming and Rain Addition Increase Phenol Oxidase Activity in Arctic Soils

    Science.gov (United States)

    Kang, H.; Seo, J.; Jang, I.; Lee, Y. K.

    2014-12-01

    Artic tundra is one of the largest carbon stocks, of which amount is estimated up to 1,600 Pg. Global climate change models predict surface temperature rise and higher precipitation during summer in Arctic regions, raising concerns about faster decomposition of organic carbon and consequent releases of CO2, CH4 and DOC. Microorganisms are directly involved in decomposition process by releasing various extracellular enzymes. In particular, phenol oxidase was noted to play a key role because it is related to dynamics of highly recalcitrant carbon, which often represents a rate-limiting step of overall decomposition. In this study, we monitored phenol oxidase activity, hydrolases (β-glucosidase, cellobiohydrolase, N-acetylglucosaminidase and aminopeptidase), microbial abundance (qPCR) and chemical properties (δ13C and δ15N signatures) of tundra soils exposed to artificial warming and rain addition, by employing a passive chamber method in Cambridge Bay, Canada. Warming and rain addition combinedly increased phenol oxidase activity while no such changes were discernible for other hydrolases. Stable isotope signature indicates that warming induced water stress to the ecosystem and that nitrogen availability may be enhanced, which is partially responsible for the changes in enzyme activities. A short-term warming (2 years) may not accelerate mineralization of easily decomposable carbon, but may affect phenol oxidase which has the longer-term influence on recalcitrant carbon.

  16. Fusion-Triggered Switching of Enzymatic Activity on an Artificial Cell Membrane

    Directory of Open Access Journals (Sweden)

    Jun-ichi Kikuchi

    2012-05-01

    Full Text Available A nanosensory membrane device was constructed for detecting liposome fusion through changes in an enzymatic activity. Inspired by a biological signal transduction system, the device design involved functionalized liposomal membranes prepared by self-assembly of the following molecular components: a synthetic peptide lipid and a phospholipid as matrix membrane components, a Schiff’s base of pyridoxal 5’-phosphate with phosphatidylethanolamine as a thermo-responsive artificial receptor, NADH-dependent L-lactate dehydrogenase as a signal amplifier, and Cu2+ ion as a signal mediator between the receptor and enzyme. The enzymatic activity of the membrane device was adjustable by changing the matrix lipid composition, reflecting the thermotropic phase transition behavior of the lipid membranes, which in turn controlled receptor binding affinity toward the enzyme-inhibiting mediator species. When an effective fusogen anionic polymer was added to these cationic liposomes, membrane fusion occurred, and the functionalized liposomal membranes responded with changes in enzymatic activity, thus serving as an effective nanosensory device for liposome fusion detection.

  17. Artificial neural networks in the evaluation of the radioactive waste drums activity

    International Nuclear Information System (INIS)

    The mathematical techniques are becoming more important to solve geometry and standard identification problems. The gamma spectrometry of radioactive waste drums would be a complex solution problem. The main difficulty is the detectors calibration for this geometry; the waste is not homogeneously distributed inside the drums, therefore there are many possible combinations between the activity and the position of these radionuclides inside the drums, making the preparation of calibration standards impracticable. This work describes the development of a methodology to estimate the activity of a 200 L radioactive waste drum, as well as a mapping of the waste distribution, using Artificial Neural Network. The neural network data set entry obtaining was based on the possible detection efficiency combination with 10 sources activities varying from 0 to 74 x 103 Bq. The set up consists of a 200 L drum divided in 5 layers. Ten detectors were positioned all the way through a parallel line to the drum axis, from 15 cm of its surface. The Cesium -137 radionuclide source was used. The 50 efficiency obtained values (10 detectors and 5 layers), combined with the 10 source intensities resulted in a 100,000 lines for 15 columns matrix, with all the possible combinations of source intensity and the Cs-137 position in the 5 layers of the drum. This archive was divided in 2 parts to compose the set of training: input and target files. The MatLab 7.0 module of neural networks was used for training. The net architecture has 10 neurons in the input layer, 18 in the hidden layer and 5 in the output layer. The training algorithm was the 'traincgb' and after 300 'epoch s' the medium square error was 0.00108172. This methodology allows knowing the detection positions answers in a heterogeneous distribution of radionuclides inside a 200 L waste drum; in consequence it is possible to estimate the total activity of the drum in the training neural network limits. The results accuracy depends on

  18. Artificial sweeteners and salts producing a metallic taste sensation activate TRPV1 receptors.

    Science.gov (United States)

    Riera, Céline E; Vogel, Horst; Simon, Sidney A; le Coutre, Johannes

    2007-08-01

    Throughout the world many people use artificial sweeteners (AS) for the purpose of reducing caloric intake. The most prominently used of these molecules include saccharin, aspartame (Nutrasweet), acesulfame-K, and cyclamate. Despite the caloric advantage they provide, one key concern in their use is their aversive aftertaste that has been characterized on a sensory level as bitter and/or metallic. Recently, it has been shown that the activation of particular T2R bitter taste receptors is partially involved with the bitter aftertaste sensation of saccharin and acesulfame-K. To more fully understand the biology behind these phenomena we have addressed the question of whether AS could stimulate transient receptor potential vanilloid-1 (TRPV1) receptors, as these receptors are activated by a large range of structurally different chemicals. Moreover, TRPV1 receptors and/or their variants are found in taste receptor cells and in nerve terminals throughout the oral cavity. Hence, TRPV1 activation could be involved in the AS aftertaste or even contribute to the poorly understood metallic taste sensation. Using Ca(2+) imaging on TRPV1 receptors heterologously expressed in the human embryonic kidney (HEK) 293 cells and on dissociated primary sensory neurons, we find that in both systems, AS activate TRPV1 receptors, and, moreover, they sensitize these channels to acid and heat. We also found that TRPV1 receptors are activated by CuSO(4), ZnSO(4), and FeSO(4), three salts known to produce a metallic taste sensation. In summary, our results identify a novel group of compounds that activate TRPV1 and, consequently, provide a molecular mechanism that may account for off tastes of sweeteners and metallic tasting salts. PMID:17567713

  19. Prominent artificial radionuclide activity in the environment of coastal Karnataka on the southwest coast of India

    Energy Technology Data Exchange (ETDEWEB)

    Narayana, Y. [Department of Studies in Physics, Mangalore University, Mangalagangotri-574 199 (India)]. E-mail: narayanay@yahoo.com; Somashekarappa, H.M.; Karunakara, N.; Avadhani, D.N.; Mahesh, H.M.; Siddappa, K. [Department of Studies in Physics, Mangalore University, Mangalagangotri-574 199 (India)

    2000-09-01

    Studies on radiation level and radionuclide distribution in the environment of coastal Karnataka were undertaken to provide baseline data for the future assessment of the impact of the nuclear and thermal power stations that are being set up in the region and to understand the behaviour of radionuclides in the environment. As part of the programme the concentrations of two important artificial radionuclides, namely {sup 90}Sr and {sup 137}Cs, have been measured in a number of environmental samples. The concentration of {sup 90}Sr is very low in most of the samples. Among the samples analysed for the concentration of {sup 137}Cs, soil samples showed elevated levels of activity in some sampling stations. Among the vegetables, brinjal (Solanum melongena. L) showed considerable activity. The internal dose due to intake of {sup 90}Sr through diet was 0.42 {mu}Sv year{sup -1} for the vegetarian population and 0.32 {mu}Sv year{sup -1} for the non-vegetarian population. The internal dose due to dietary intake of {sup 137}Cs was found to be 0.34 {mu}Sv year{sup -1} and 0.26 {mu}Sv year{sup -1} respectively for the vegetarian and non-vegetarian population. The results are discussed in the light of the literature values reported for other environs of India and abroad and appropriate inferences are drawn. (author)

  20. Prominent artificial radionuclide activity in the environment of coastal Karnataka on the southwest coast of India

    International Nuclear Information System (INIS)

    Studies on radiation level and radionuclide distribution in the environment of coastal Karnataka were undertaken to provide baseline data for the future assessment of the impact of the nuclear and thermal power stations that are being set up in the region and to understand the behaviour of radionuclides in the environment. As part of the programme the concentrations of two important artificial radionuclides, namely 90Sr and 137Cs, have been measured in a number of environmental samples. The concentration of 90Sr is very low in most of the samples. Among the samples analysed for the concentration of 137Cs, soil samples showed elevated levels of activity in some sampling stations. Among the vegetables, brinjal (Solanum melongena. L) showed considerable activity. The internal dose due to intake of 90Sr through diet was 0.42 μSv year-1 for the vegetarian population and 0.32 μSv year-1 for the non-vegetarian population. The internal dose due to dietary intake of 137Cs was found to be 0.34 μSv year-1 and 0.26 μSv year-1 respectively for the vegetarian and non-vegetarian population. The results are discussed in the light of the literature values reported for other environs of India and abroad and appropriate inferences are drawn. (author)

  1. Gender specific changes in cortical activation patterns during exposure to artificial gravity

    Science.gov (United States)

    Schneider, Stefan; Robinson, Ryan; Smith, Craig; von der Wiesche, Melanie; Goswami, Nandu

    2014-11-01

    Keeping astronauts healthy during long duration spaceflight remains a challenge. Artificial gravity (AG) generated by a short arm human centrifuges (SAHC) is proposed as the next generation of integrated countermeasure devices that will allow human beings to safely spend extended durations in space, although comparatively little is known about any psychological side effects of AG on brain function. 16 participants (8 male and 8 female, GENDER) were exposed to 10 min at a baseline gravitational load (G-Load) of +.03 Gz, then 10 min at +.6 Gz for females and +.8 Gz for males, before being exposed to increasing levels of AG in a stepped manner by increasing the acceleration by +.1 Gz every 3 min until showing signs of pre-syncope. EEG recordings were taken of brain activity during 2 min time periods at each AG level. Analysing the results of the mixed total population of participants by two way ANOVA, a significant effect of centrifugation on alpha and beta activity was found (presponses identified in this study may have wider implications for EEG and AG research.

  2. Morphology controlled bulk synthesis of disc-shaped WO{sub 3} powder and evaluation of its photocatalytic activity for the degradation of phenols

    Energy Technology Data Exchange (ETDEWEB)

    Aslam, M. [Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Ismail, Iqbal M.I. [Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Chemistry Department, Faculty of Science, King Abdulaziz University, PO Box 80203, Jeddah 21589 (Saudi Arabia); Chandrasekaran, S. [Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah 21589 (Saudi Arabia); Hameed, A., E-mail: afmuhammad@kau.edu.sa [Centre of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah 21589 (Saudi Arabia); National Centre for Physics, Quaid-e-Azam University, Islamabad 44000 (Pakistan)

    2014-07-15

    Graphical abstract: - Highlights: • User friendly procedure for the synthesis of disc-shaped WO{sub 3}. • Superoxide anion radicals are the major contributors in photocatalytic degradation process. • Electron withdrawing substituents facilitates the degradation process. • Nitrite ions are converted to NO{sub 2} gas in 2-nitophenol degradation. - Abstract: The surfactant assisted synthesis of disc-shaped WO{sub 3} powder and its photocatalytic performance in sunlight exposure is reported. UV–vis DRS, XRD and FESEM characterized the synthesized WO{sub 3}. The synthesized powder exhibited a bandgap of ∼2.55 eV with cubic lattice and high crystallinity. The photocatalytic activity of the synthesized WO{sub 3} was examined for the degradation of phenol, resorcinol, 2-chlorophenol and 2-nitrophenol in complete spectrum and visible segment of sunlight. The highly efficient degradation/mineralization of 2-chloro and 2-nitrophenol compared to that of phenol and resorcinol, under identical experimental conditions, suggested the regulatory role of substituents attached to the aromatic ring in degradation/mineralization process. The time-scale HPLC degradation profiles, identification of intermediates by GC-MS and removal of organic carbon during the course of reaction were utilized to approximate the possible route of degradation/mineralization of phenolic substrates. The measurement of the anions released during the photocatalytic process was used to identify the nature of the major oxidants (O{sub 2}{sup •} {sup −}, OH{sup •} ) and the possible interaction sites. A significant decrease in the photocatalytic activity of synthesized WO{sub 3}, ∼50%, was observed in visible portion of sunlight however, a sustained activity was observed in the repeated exposures.

  3. Morphology controlled bulk synthesis of disc-shaped WO3 powder and evaluation of its photocatalytic activity for the degradation of phenols

    International Nuclear Information System (INIS)

    Graphical abstract: - Highlights: • User friendly procedure for the synthesis of disc-shaped WO3. • Superoxide anion radicals are the major contributors in photocatalytic degradation process. • Electron withdrawing substituents facilitates the degradation process. • Nitrite ions are converted to NO2 gas in 2-nitophenol degradation. - Abstract: The surfactant assisted synthesis of disc-shaped WO3 powder and its photocatalytic performance in sunlight exposure is reported. UV–vis DRS, XRD and FESEM characterized the synthesized WO3. The synthesized powder exhibited a bandgap of ∼2.55 eV with cubic lattice and high crystallinity. The photocatalytic activity of the synthesized WO3 was examined for the degradation of phenol, resorcinol, 2-chlorophenol and 2-nitrophenol in complete spectrum and visible segment of sunlight. The highly efficient degradation/mineralization of 2-chloro and 2-nitrophenol compared to that of phenol and resorcinol, under identical experimental conditions, suggested the regulatory role of substituents attached to the aromatic ring in degradation/mineralization process. The time-scale HPLC degradation profiles, identification of intermediates by GC-MS and removal of organic carbon during the course of reaction were utilized to approximate the possible route of degradation/mineralization of phenolic substrates. The measurement of the anions released during the photocatalytic process was used to identify the nature of the major oxidants (O2• −, OH• ) and the possible interaction sites. A significant decrease in the photocatalytic activity of synthesized WO3, ∼50%, was observed in visible portion of sunlight however, a sustained activity was observed in the repeated exposures

  4. Seasonal prediction of tropical cyclone activity over the north Indian Ocean using three artificial neural networks

    Science.gov (United States)

    Nath, Sankar; Kotal, S. D.; Kundu, P. K.

    2016-03-01

    Three artificial neural network (ANN) methods, namely, multilayer perceptron (MLP), radial basis function (RBF) and generalized regression neural network (GRNN) are utilized to predict the seasonal tropical cyclone (TC) activity over the north Indian Ocean (NIO) during the post-monsoon season (October, November, December). The frequency of TC and large-scale climate variables derived from NCEP/NCAR reanalysis dataset of resolution 2.5° × 2.5° were analyzed for the period 1971-2013. Data for the years 1971-2002 were used for the development of the models, which were tested with independent sample data for the year 2003-2013. Using the correlation analysis, the five large-scale climate variables, namely, geopotential height at 500 hPa, relative humidity at 500 hPa, sea-level pressure, zonal wind at 700 hPa and 200 hPa for the preceding month September, are selected as potential predictors of the post-monsoon season TC activity. The result reveals that all the three different ANN methods are able to provide satisfactory forecast in terms of the various metrics, such as root mean-square error (RMSE), standard deviation (SD), correlation coefficient (r), and bias and index of agreement (d). Additionally, leave-one-out cross validation (LOOCV) method is also performed and the forecast skill is evaluated. The results show that the MLP model is found to be superior to the other two models (RBF, GRNN). The (MLP) is expected to be very useful to operational forecasters for prediction of TC activity.

  5. Determination of DPPH free radical scavenging activity: application of artificial neural networks.

    Science.gov (United States)

    Musa, Khalid Hamid; Abdullah, Aminah; Al-Haiqi, Ahmed

    2016-03-01

    A new computational approach for the determination of 2,2-diphenyl-1-picrylhydrazyl free radical scavenging activity (DPPH-RSA) in food is reported, based on the concept of machine learning. Trolox standard was mix with DPPH at different concentrations to produce different colors from purple to yellow. Artificial neural network (ANN) was trained on a typical set of images of the DPPH radical reacting with different levels of Trolox. This allowed the neural network to classify future images of any sample into the correct class of RSA level. The ANN was then able to determine the DPPH-RSA of cinnamon, clove, mung bean, red bean, red rice, brown rice, black rice and tea extract and the results were compared with data obtained using a spectrophotometer. The application of ANN correlated well to the spectrophotometric classical procedure and thus do not require the use of spectrophotometer, and it could be used to obtain semi-quantitative results of DPPH-RSA. PMID:26471610

  6. Active galactic nuclei synapses: X-ray versus optical classifications using artificial neural networks

    CERN Document Server

    Gonzalez-Martin, O; Acosta-Pulido, J A; Masegosa, J; Papadakis, I E; Rodriguez-Espinosa, J M; Marquez, I; Hernandez-Garcia, L

    2014-01-01

    (Abridged) Many classes of active galactic nuclei (AGN) have been defined entirely throughout optical wavelengths while the X-ray spectra have been very useful to investigate their inner regions. However, optical and X-ray results show many discrepancies that have not been fully understood yet. The aim of this paper is to study the "synapses" between the X-ray and optical classifications. For the first time, the new EFLUXER task allowed us to analyse broad band X-ray spectra of emission line nuclei (ELN) without any prior spectral fitting using artificial neural networks (ANNs). Our sample comprises 162 XMM-Newton/pn spectra of 90 local ELN in the Palomar sample. It includes starbursts (SB), transition objects (T2), LINERs (L1.8 and L2), and Seyferts (S1, S1.8, and S2). The ANNs are 90% efficient at classifying the trained classes S1, S1.8, and SB. The S1 and S1.8 classes show a wide range of S1- and S1.8-like components. We suggest that this is related to a large degree of obscuration at X-rays. The S1, S1.8...

  7. DETECTING ACTIVE GALACTIC NUCLEI USING MULTI-FILTER IMAGING DATA. II. INCORPORATING ARTIFICIAL NEURAL NETWORKS

    Energy Technology Data Exchange (ETDEWEB)

    Dong, X. Y.; De Robertis, M. M., E-mail: xydong@yorku.ca [Physics and Astronomy Department, York University, Toronto, ON M3J 1P3 (Canada)

    2013-10-01

    This is the second paper of the series Detecting Active Galactic Nuclei Using Multi-filter Imaging Data. In this paper we review shapelets, an image manipulation algorithm, which we employ to adjust the point-spread function (PSF) of galaxy images. This technique is used to ensure the image in each filter has the same and sharpest PSF, which is the preferred condition for detecting AGNs using multi-filter imaging data as we demonstrated in Paper I of this series. We apply shapelets on Canada-France-Hawaii Telescope Legacy Survey Wide Survey ugriz images. Photometric parameters such as effective radii, integrated fluxes within certain radii, and color gradients are measured on the shapelets-reconstructed images. These parameters are used by artificial neural networks (ANNs) which yield: photometric redshift with an rms of 0.026 and a regression R-value of 0.92; galaxy morphological types with an uncertainty less than 2 T types for z ≤ 0.1; and identification of galaxies as AGNs with 70% confidence, star-forming/starburst (SF/SB) galaxies with 90% confidence, and passive galaxies with 70% confidence for z ≤ 0.1. The incorporation of ANNs provides a more reliable technique for identifying AGN or SF/SB candidates, which could be very useful for large-scale multi-filter optical surveys that also include a modest set of spectroscopic data sufficient to train neural networks.

  8. DETECTING ACTIVE GALACTIC NUCLEI USING MULTI-FILTER IMAGING DATA. II. INCORPORATING ARTIFICIAL NEURAL NETWORKS

    International Nuclear Information System (INIS)

    This is the second paper of the series Detecting Active Galactic Nuclei Using Multi-filter Imaging Data. In this paper we review shapelets, an image manipulation algorithm, which we employ to adjust the point-spread function (PSF) of galaxy images. This technique is used to ensure the image in each filter has the same and sharpest PSF, which is the preferred condition for detecting AGNs using multi-filter imaging data as we demonstrated in Paper I of this series. We apply shapelets on Canada-France-Hawaii Telescope Legacy Survey Wide Survey ugriz images. Photometric parameters such as effective radii, integrated fluxes within certain radii, and color gradients are measured on the shapelets-reconstructed images. These parameters are used by artificial neural networks (ANNs) which yield: photometric redshift with an rms of 0.026 and a regression R-value of 0.92; galaxy morphological types with an uncertainty less than 2 T types for z ≤ 0.1; and identification of galaxies as AGNs with 70% confidence, star-forming/starburst (SF/SB) galaxies with 90% confidence, and passive galaxies with 70% confidence for z ≤ 0.1. The incorporation of ANNs provides a more reliable technique for identifying AGN or SF/SB candidates, which could be very useful for large-scale multi-filter optical surveys that also include a modest set of spectroscopic data sufficient to train neural networks

  9. Seeing by Touch: Evaluation of a Soft Biologically-Inspired Artificial Fingertip in Real-Time Active Touch

    Directory of Open Access Journals (Sweden)

    Tareq Assaf

    2014-02-01

    Full Text Available Effective tactile sensing for artificial platforms remains an open issue in robotics. This study investigates the performance of a soft biologically-inspired artificial fingertip in active exploration tasks. The fingertip sensor replicates the mechanisms within human skin and offers a robust solution that can be used both for tactile sensing and gripping/manipulating objects. The softness of the optical sensor’s contact surface also allows safer interactions with objects. High-level tactile features such as edges are extrapolated from the sensor’s output and the information is used to generate a tactile image. The work presented in this paper aims to investigate and evaluate this artificial fingertip for 2D shape reconstruction. The sensor was mounted on a robot arm to allow autonomous exploration of different objects. The sensor and a number of human participants were then tested for their abilities to track the raised perimeters of different planar objects and compared. By observing the technique and accuracy of the human subjects, simple but effective parameters were determined in order to evaluate the artificial system’s performance. The results prove the capability of the sensor in such active exploration tasks, with a comparable performance to the human subjects despite it using tactile data alone whereas the human participants were also able to use proprioceptive cues.

  10. Bio-inspired electron-delivering system for reductive activation of dioxygen at metal centres towards artificial flavoenzymes.

    Science.gov (United States)

    Roux, Yoann; Ricoux, Rémy; Avenier, Frédéric; Mahy, Jean-Pierre

    2015-01-01

    Development of artificial systems, capable of delivering electrons to metal-based catalysts for the reductive activation of dioxygen, has been proven very difficult for decades, constituting a major scientific lock for the elaboration of environmentally friendly oxidation processes. Here we demonstrate that the incorporation of a flavin mononucleotide (FMN) in a water-soluble polymer, bearing a locally hydrophobic microenvironment, allows the efficient reduction of the FMN by NADH. This supramolecular entity is then capable of catalysing a very fast single-electron reduction of manganese(III) porphyrin by splitting the electron pair issued from NADH. This is fully reminiscent of the activity of natural reductases such as the cytochrome P450 reductases with kinetic parameters, which are three orders of magnitude faster compared with other artificial systems. Finally, we show as a proof of concept that the reduced manganese porphyrin activates dioxygen and catalyses the oxidation of organic substrates in water. PMID:26419885

  11. Double rupture disc experience

    International Nuclear Information System (INIS)

    Result of these observations, comparisons and evaluations can be summarized in the following list of concerns regarding the use of double rupture discs coupled to the liquid space of a steam generator that is subjected to a large leak sodium water reaction event. Single rupture disc show delayed collapse characteristics in LLTR Series I and double disc assemblies are presumed to be more complex with additional delay before opening to give pressure relief. Delayed failure increases pressures in the IHTS and must be adequately covered by design requirements. With CRBR design, the first disc may fail only partially reducing the loading on the second disc with the result that relief performance may not meet requirements

  12. Kinetics of aerobically activated sludge on terylene artificial silk printing and dyeing wastewater treatment

    Institute of Scientific and Technical Information of China (English)

    官宝红; 吴忠标; 徐根良

    2004-01-01

    Aerobically activated sludge processing was carried out to treat terylene artificial silk printing and dyeing wastewater (TPD wastewater) in a lab-scale experiment, focusing on the kinetics of the COD removal. The kinetics parameters determined from experiment were applied to evaluate the biological treatability of wastewater. Experiments showed that COD removal could be divided into two stages, in which the ratio BOD/COD (B/C) was the key factor for stage division. At the rapid-removal stage with B/C>0.1, COD removal could be described by a zero order reaction. At the moderate-removal stage with B/C<0.1, COD removal could be described by a first order reaction. Then Monod equation was introduced to indicate COD removal. The reaction rate constant (K) and half saturation constant (KS) were 0.0208-0.0642 L/(gMLSS)·h and 0.44-0.59 (gCOD)/L respectively at 20 ℃-35 ℃. Activation energy (Ea) was 6.05×104 J/mol. By comparison of kinetic parameters, the biological treatability of TPD wastewater was superior to that of traditional textile wastewater. But COD removal from TPD-wastewater was much more difficult than that from domestic and industrial wastewater, such as papermaking, beer, phenol wastewater, etc. The expected effluent quality strongly related to un-biodegradable COD and kinetics rather than total COD. The results provide useful basis for further scaling up and efficient operation of TPD wastewater treatment.

  13. Kinetics of aerobically activated sludge on terylene artificial silk printing and dyeing wastewater treatment

    Institute of Scientific and Technical Information of China (English)

    官宝红; 吴忠标; 徐根良

    2004-01-01

    Aerobically activated sludge processing was carried out to treat terylene artificial silk printing and dyeing wastewater (TPD wastewater) in a lab-scale experiment, focusing on the kinetics of the COD removal.The kinetics parameters determined from experiment were applied to evaluate the biological treatability of wastewater.Experiments showed that COD removal could be divided into two stages,in which the ratio BOD/COD (B/C) was the key factor for stage division.At the rapid-removal stage with B/C>0.1,COD removal could be described by a zero order reaction. At the moderate-removal stage with B/C<0.1,COD removal could be described by a first order reaction. Then Monod equation was introduced to indicate COD removal. The reaction rate constant (K) and half saturation constant (Ks) were 0.0208-0.0642L/(gMLSS)h and 0.44-0.59(gCOD)/L respectively at 20℃-35℃.Activation energy (Ea) was 6.05×104 J/mol.By comparison of kinetic parameters, the biological treatability of TPD wastewater was superior to that of traditional textile wastewater.But COD removal from TPD-wastewater was much more difficult than that from domestic and industrial wastewater,such as papermaking, beer, phenol wastewater, etc.The expected effluent quality strongly related to un-biodegradable COD and kinetics rather than total COD. The results provide useful basis for further scaling up an defficient operation of TPD wastewater treatment.

  14. Follow-up Study on the Motion Range after Treatment of Degenerative Disc Disease with the Bryan Cervical Disc Prosthesis

    Institute of Scientific and Technical Information of China (English)

    YANG Shuhua; HU Yong; ZHAO Jijun; HE Xianfeng; LIU Yong; XU Weihua; DU Jingyuan; FU Dehao

    2007-01-01

    This study examined effect of a new intervertebral cervical disc prosthesis in relieving the neurological symptoms and signs, improving the patients' ability to perform daily activities, reducing pain, and maintaining the stability and segmental motion. From December 2003 to October 2004, 12 patients, who had received 14 replacements of cervical artificial discs, were followed-up for 2 to 8 months (with a mean of 5.2 months). Of them 5 had cervical spondylotic myelopathy and 7 had cervical disc herniation. The patients included 7 males and 5 females, with their age ranging from 35 to 62 y and a mean of 50.3 y. Single-level replacements were performed in 10 cases and 2 cases received two-level replacement. Operation time of the single-level surgery averaged 130±50 min and the time of two-level surgery was 165±53 min on average (from skin incision to skin suturing).Neurological or vascular complications during or after surgery was not observed. Japanese Orthopedic Association scores (JOA scores) increased from 8.6 to 15.8 on average. There was no prothesis subsidence or excursion. Replaced segments were stable and the range of motion was partially restored, being 4.68° (3.6°-6.1°) in flexion and extension position and 3.51° (2.5°-4.6°) 3.42° (2.6°-4.3°) in left and right bending position. No obvious loss of physiological curvature was noted. CT or MRI follow-up showed that excursion was less than 1.5 mm) in 2 of 14 levels and between 1.5 mm and 3 mm) in 1 of 14 levels. No ossification in the replaced levels was observed. It is concluded that satisfactory short-term results were achieved in the 12 cases of artificial disc replacements. Different from anterior cervical discectomy and fusion, the replacement could achieve quick functional recovery and did not lead to the movement limitation of cervical vertebrae. At least a 5-years follow-up was needed to assess the long-term effect of the prosthesis on its neighboring segments.

  15. On the vertical-shear instability in astrophysical discs

    CERN Document Server

    Barker, Adrian J

    2015-01-01

    We explore the linear stability of astrophysical discs exhibiting vertical shear, which arises when there is a radial variation in the temperature or entropy. Such discs are subject to a "vertical-shear instability", which recent nonlinear simulations have shown to drive hydrodynamic activity in the MRI-stable regions of protoplanetary discs. We first revisit locally isothermal discs using the quasi-global reduced model derived by Nelson et al. (2013). This analysis is then extended to global axisymmetric perturbations in a cylindrical domain. We also derive and study a reduced model describing discs with power law radial entropy profiles ("locally polytropic discs"), which are somewhat more realistic in that they possess physical (as opposed to numerical) surfaces. In all cases the fastest growing modes have very short wavelengths and are localised at the disc surfaces (if present), where the vertical shear is maximal. An additional class of modestly growing vertically global body modes is excited, correspon...

  16. Reconstructing the star formation history of the Milky Way disc(s) from chemical abundances

    Science.gov (United States)

    Snaith, O.; Haywood, M.; Di Matteo, P.; Lehnert, M. D.; Combes, F.; Katz, D.; Gómez, A.

    2015-06-01

    We develop a chemical evolution model to study the star formation history of the Milky Way. Our model assumes that the Milky Way has formed from a closed-box-like system in the inner regions, while the outer parts of the disc have experienced some accretion. Unlike the usual procedure, we do not fix the star formation prescription (e.g. Kennicutt law) to reproduce the chemical abundance trends. Instead, we fit the abundance trends with age to recover the star formation history of the Galaxy. Our method enables us to recover the star formation history of the Milky Way in the first Gyrs with unprecedented accuracy in the inner (R 9-10 kpc) discs, as sampled in the solar vicinity. We show that half the stellar mass formed during the thick-disc phase in the inner galaxy during the first 4-5 Gyr. This phase was followed by a significant dip in star formation activity (at 8-9 Gyr) and a period of roughly constant lower-level star formation for the remaining 8 Gyr. The thick-disc phase has produced as many metals in 4 Gyr as the thin-disc phase in the remaining 8 Gyr. Our results suggest that a closed-box model is able to fit all the available constraints in the inner disc. A closed-box system is qualitatively equivalent to a regime where the accretion rate maintains a high gas fraction in the inner disc at high redshift. In these conditions the SFR is mainly governed by the high turbulence of the interstellar medium. By z ~ 1 it is possible that most of the accretion takes place in the outer disc, while the star formation activity in the inner disc is mostly sustained by the gas that is not consumed during the thick-disc phase and the continuous ejecta from earlier generations of stars. The outer disc follows a star formation history very similar to that of the inner disc, although initiated at z ~ 2, about 2 Gyr before the onset of the thin-disc formation in the inner disc.

  17. Bio-inspired electron-delivering system for reductive activation of dioxygen at metal centres towards artificial flavoenzymes

    OpenAIRE

    Roux, Yoann; Ricoux, Rémy; Avenier, Frédéric; Mahy, Jean-Pierre

    2015-01-01

    Development of artificial systems, capable of delivering electrons to metal-based catalysts for the reductive activation of dioxygen, has been proven very difficult for decades, constituting a major scientific lock for the elaboration of environmentally friendly oxidation processes. Here we demonstrate that the incorporation of a flavin mononucleotide (FMN) in a water-soluble polymer, bearing a locally hydrophobic microenvironment, allows the efficient reduction of the FMN by NADH. This supra...

  18. Dependence of activity concentration of natural and artificial radionuclides on depth in soil samples from Antalya in Turkey

    Science.gov (United States)

    Eke, Canel; Agar, Osman; Boztosun, Ismail

    2015-04-01

    In this study, we attempt to determine the dependence of activity concentration of natural (238U, 232Th, 40K) and artificial (137Cs) radionuclides on depth in soil samples from Antalya in Turkey. Soil samples were collected at different depths (0-10 cm, 10-30 cm, 30-50 cm, 50-70 cm, 70-100 cm and 100-200 cm). Each soil samples were counted by using a high purity Germanium detector (HpGe). For each soil sample, activity concentration, absorbed dose rate, radium equivalent activity, external and internal hazard index were calculated and compared with the published results.

  19. Optic disc oedema

    DEFF Research Database (Denmark)

    Nielsen, Marianne Kromann; Hamann, Steffen

    2014-01-01

    Optic disc oedema describes the nonspecific, localized swelling of the optic nerve head regardless of aetiology. Therefore, differentiating among the various aetiologies depends on a thorough history and knowledge of the clinical characteristics of the underlying conditions. Papilloedema strictly...... refers to optic disc oedema as a consequence of elevated intracranial pressure. It is usually a bilateral condition and visual function is preserved until late. Optic disc oedema caused by an anterior optic neuropathy is usually unilateral and accompanied by the loss of visual function....

  20. Proteomic signature of the murine intervertebral disc.

    Directory of Open Access Journals (Sweden)

    Matthew R McCann

    Full Text Available Low back pain is the most common musculoskeletal problem and the single most common cause of disability, often attributed to degeneration of the intervertebral disc. Lack of effective treatment is directly related to our limited understanding of the pathways responsible for maintaining disc health. While transcriptional analysis has permitted initial insights into the biology of the intervertebral disc, complete proteomic characterization is required. We therefore employed liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS protein/peptide separation and mass spectrometric analyses to characterize the protein content of intervertebral discs from skeletally mature wild-type mice. A total of 1360 proteins were identified and categorized using PANTHER. Identified proteins were primarily intracellular/plasma membrane (35%, organelle (30%, macromolecular complex (10%, extracellular region (9%. Molecular function categorization resulted in three distinct categories: catalytic activity (33%, binding (molecule interactions (29%, and structural activity (13%. To validate our list, we confirmed the presence of 14 of 20 previously identified IVD-associated markers, including matrix proteins, transcriptional regulators, and secreted proteins. Immunohistochemical analysis confirmed distinct localization patterns of select protein with the intervertebral disc. Characterization of the protein composition of healthy intervertebral disc tissue is an important first step in identifying cellular processes and pathways disrupted during aging or disease progression.

  1. Sweet taste receptor expression in ruminant intestine and its activation by artificial sweeteners to regulate glucose absorption.

    Science.gov (United States)

    Moran, A W; Al-Rammahi, M; Zhang, C; Bravo, D; Calsamiglia, S; Shirazi-Beechey, S P

    2014-01-01

    Absorption of glucose from the lumen of the intestine into enterocytes is accomplished by sodium-glucose co-transporter 1 (SGLT1). In the majority of mammalian species, expression (this includes activity) of SGLT1 is upregulated in response to increased dietary monosaccharides. This regulatory pathway is initiated by sensing of luminal sugar by the gut-expressed sweet taste receptor. The objectives of our studies were to determine (1) if the ruminant intestine expresses the sweet taste receptor, which consists of two subunits [taste 1 receptor 2 (T1R2) and 3 (T1R3)], and other key signaling molecules required for SGLT1 upregulation in nonruminant intestines, and (2) whether T1R2-T1R3 sensing of artificial sweeteners induces release of glucagon-like peptide-2 (GLP-2) and enhances SGLT1 expression. We found that the small intestine of sheep and cattle express T1R2, T1R3, G-protein gustducin, and GLP-2 in enteroendocrine L-cells. Maintaining 110-d-old ruminating calves for 60d on a diet containing a starter concentrate and the artificial sweetener Sucram (consisting of saccharin and neohesperidin dihydrochalcone; Pancosma SA, Geneva, Switzerland) enhances (1) Na(+)-dependent d-glucose uptake by over 3-fold, (2) villus height and crypt depth by 1.4- and 1.2-fold, and (3) maltase- and alkaline phosphatase-specific activity by 1.5-fold compared to calves maintained on the same diet without Sucram. No statistically significant differences were observed for rates of intestinal glucose uptake, villus height, crypt depth, or enzyme activities between 50-d-old milk-fed calves and calves maintained on the same diet containing Sucram. When adult cows were kept on a diet containing 80:20 ryegrass hay-to-concentrate supplemented with Sucram, more than a 7-fold increase in SGLT1 protein abundance was noted. Collectively, the data indicate that inclusion of this artificial sweetener enhances SGLT1 expression and mucosal growth in ruminant animals. Exposure of ruminant sheep

  2. LUMBAR DISC HERNIATION

    OpenAIRE

    Vialle, Luis Roberto; Vialle, Emiliano Neves; Suárez Henao, Juan Esteban; Giraldo, Gustavo

    2015-01-01

    Lumbar disc herniation is the most common diagnosis among the degenerative abnormalities of the lumbar spine (affecting 2 to 3% of the population), and is the principal cause of spinal surgery among the adult population. The typical clinical picture includes initial lumbalgia, followed by progressive sciatica. The natural history of disc herniation is one of rapid resolution of the symptoms (four to six weeks). The initial treatment should be conservative, managed through medication and physi...

  3. ANALYSIS OF MONOPOLE ANTENNA ON CIRCULAR DISC BY MODE MATCHING

    Institute of Scientific and Technical Information of China (English)

    Sun Baohua; Zhang Fushun; Liu Qizhong

    2001-01-01

    Mode matching is used for the analysis of monopole antenna on circular disc, which is achieved by developing a novel model consisting of two artificial ground planes above and bellow the monopole antenna. Using this model, the input impedance is computed and compared with measured data reported in literatures, and excellent agreement is observed.

  4. Radicular interdural lumbar disc herniation

    OpenAIRE

    Akhaddar, Ali; Boulahroud, Omar; Elasri, Abad; Elmostarchid, Brahim; Boucetta, Mohammed

    2009-01-01

    Intraradicular lumbar disc herniation is a rare complication of disc disease that is generally diagnosed only during surgery. The mechanism for herniated disc penetration into the intradural space is not known with certainty, but adhesion between the radicular dura and the posterior longitudinal ligament was suggested as the most important condition. The authors report the first case of an intraradicular lumbar disc herniation without subdural penetration; the disc hernia was lodged between t...

  5. Construction of GPx active centers on natural protein nanodisk/nanotube: a new way to develop artificial nanoenzyme.

    Science.gov (United States)

    Hou, Chunxi; Luo, Quan; Liu, Jinliang; Miao, Lu; Zhang, Chunqiu; Gao, Yuzhou; Zhang, Xiyu; Xu, Jiayun; Dong, Zeyuan; Liu, Junqiu

    2012-10-23

    Construction of catalytic centers on natural protein aggregates is a challenging topic in biomaterial and biomedicine research. Here we report a novel construction of artificial nanoenzyme with glutathione peroxidase (GPx)-like function. By engineering the surface of tobacco mosaic virus (TMV) coat protein, the main catalytic components of GPx were fabricated on TMV protein monomers. Through direct self-assembly of the functionalized viral coat proteins, the multi-GPx centers were installed on these well-defined nanodisks or nanotubes. With the help of muti-selenoenzyme centers, the resulting organized nanoenzyme exhibited remarkable GPx activity, even approaching the level of natural GPx. The antioxidation study on subcell mitochondrial level demonstrated that virus-based nanoenzyme exerted excellent capacity for protecting cell from oxidative damage. This strategy represents a new way to develop artificial nanoenzymes. PMID:22992167

  6. Radially truncated galactic discs

    CERN Document Server

    De Grijs, R; Wesson, K H; Grijs, Richard de; Kregel, Michiel; Wesson, Karen H.

    2000-01-01

    We present the first results of a systematic analysis of radially truncatedexponential discs for four galaxies of a sample of disc-dominated edge-onspiral galaxies. Edge-on galaxies are very useful for the study of truncatedgalactic discs, since we can follow their light distributions out to largerradii than in less highly inclined galaxies. The origin of these truncationsand their asymmetry and sharpness are helpful to better constrain theories ofgalaxy formation. In general, the discs of our sample galaxies are truncated at similar radiion either side of their centres. With the exception of the disc of ESO 416-G25,it appears that our sample galaxies are closely symmetric, in terms of both thesharpness of their disc truncations and the truncation length. However, thetruncations occur over a larger region and not as abruptly as found by van derKruit & Searle (KS1-4). We show that the truncated luminosity distributions of our sample galaxies,if also present in the mass distributions, comfortably meet the r...

  7. Identical location transmission electron microscopy in combination with rotating disc electrode measurements. The activity of fuel cell catalysts and their degradation

    Energy Technology Data Exchange (ETDEWEB)

    Schloegl, Katrin G.

    2011-07-13

    As an alternative to conventional combustion engines, the Proton Exchange Membrane Fuel Cell (PEMFC) using hydrogen as a fuel is a promising concept owing to its potential independence from fossil fuels, high efficiency and zero emissions. Concerning its commercial viability, the fundamental problem of high system cost per power output and lifetime is closely related to finding more active and stable catalysts for the oxygen reduction reaction. In the presented work, several methods are combined to examine the parameters and processes responsible for both activity and degradation of platinum-based catalysts. Degradation mechanisms are scrutinized by means of electrochemical measurements with the rotating disc electrode in combination with a recently developed TEM technique, which allows for the comparison of identical locations before and after accelerated stress tests. (orig.) [German] Die mit Wasserstoff betriebene Proton Exchange Membrane Brennstoffzelle (PEMFC) stellt aufgrund ihrer potentiellen Unabhaengigkeit von fossilen Energietraegern, ihrem hohen Wirkungsgrad und fehlendem Schadstoffausstoss eine vielversprechende Alternative zum konventionellen Verbrennungsmotor dar. Das grundlegende Problem der zu hohen Systemkosten und zu geringen Lebensdauer fuer kommerzielle Anwendungen ist eng mit der Entwicklung aktiverer und stabiler Elektrokatalysatoren fuer die Sauerstoffreduktion verknuepft. In der vorliegenden Arbeit werden verschiedene Methoden kombiniert, um die Parameter und Prozesse zu untersuchen, welche fuer die Aktivitaet und Degradation platinbasierter Katalysatoren verantwortlich sind. Zur Aufklaerung vorliegender Degradationsmechanismen werden elektrochemische Messungen mit der rotierenden Scheibenelektrode in Kombination mit einer neu entwickelten TEM Methode eingesetzt, welche es ermoeglicht, identische Stellen vor und nach beschleunigten Degradationstests zu untersuchen.

  8. Artificial intelligence

    CERN Document Server

    Hunt, Earl B

    1975-01-01

    Artificial Intelligence provides information pertinent to the fundamental aspects of artificial intelligence. This book presents the basic mathematical and computational approaches to problems in the artificial intelligence field.Organized into four parts encompassing 16 chapters, this book begins with an overview of the various fields of artificial intelligence. This text then attempts to connect artificial intelligence problems to some of the notions of computability and abstract computing devices. Other chapters consider the general notion of computability, with focus on the interaction bet

  9. Activation of JNK signaling links IgI mutations to disruption of the cell polarity and epithelial organization in Drosophila imaginal discs

    Institute of Scientific and Technical Information of China (English)

    Ming-wei Zhu; Tian-chi Xin; Shun-yan Weng; Yin Gao; Ying-jie Zhang; Qi Li; Ming-fa Li

    2010-01-01

    Dear Editor, Identification of Drosophila melanogaster as a model organism for cancer research has facilitated the exploration of human tumor malignancy. In Drosophila, lossof-function mutations in the neoplastic tumor suppressor genes (nTSGs) lethal(2)giant larvae (lgl), discs large (dlg) or scribble (scrib) cause a malignant tumor-like phenotype characteristic of disrupted cell polarity and overgrowth in epithelial tissues such as imaginal discs [1].

  10. Characterisation of global flow and local fluctuations in 3D SPH simulations of protoplanetary discs

    CERN Document Server

    Arena, Serena

    2013-01-01

    A complete and detailed knowledge of the structure of the gaseous component in protoplanetary discs is essential to the study of dust evolution during the early phases of pre-planetesimal formation. The aim of this paper is to determine if three-dimensional accretion discs simulated by the Smoothed Particle Hydrodynamics (SPH) method can reproduce the observational data now available and the expected turbulent nature of protoplanetary discs. The investigation is carried out by setting up a suite of diagnostic tools specifically designed to characterise both the global flow and the fluctuations of the gaseous disc. The main result concerns the role of the artificial viscosity implementation in the SPH method: in addition to the already known ability of SPH artificial viscosity to mimic a physical-like viscosity under specific conditions, we show how the same artificial viscosity prescription behaves like an implicit turbulence model. In fact, we identify a threshold for the parameters in the standard artificia...

  11. Enhancing the Activity of Peptide-Based Artificial Hydrolase with Catalytic Ser/His/Asp Triad and Molecular Imprinting.

    Science.gov (United States)

    Wang, Mengfan; Lv, Yuqi; Liu, Xiaojing; Qi, Wei; Su, Rongxin; He, Zhimin

    2016-06-01

    In this study, an artificial hydrolase was developed by combining the catalytic Ser/His/Asp triad with N-fluorenylmethoxycarbonyl diphenylalanine (Fmoc-FF), followed by coassembly of the peptides into nanofibers (CoA-HSD). The peptide-based nanofibers provide an ideal supramolecular framework to support the functional groups. Compared with the self-assembled catalytic nanofibers (SA-H), which contain only the catalytic histidine residue, the highest activity of CoA-HSD occurs when histidine, serine, and aspartate residues are at a ratio of 40:1:1. This indicates that the well-ordered nanofiber structure and the synergistic effects of serine and aspartate residues contribute to the enhancement in activity. Additionally, for the first time, molecular imprinting was applied to further enhance the activity of the peptide-based artificial enzyme (CoA-HSD). p-NPA was used as the molecular template to arrange the catalytic Ser/His/Asp triad residues in the proper orientation. As a result, the activity of imprinted coassembled CoA-HSD nanofibers is 7.86 times greater than that of nonimprinted CoA-HSD and 13.48 times that of SA-H. PMID:27191381

  12. Crystallization of Self-Propelled Hard Discs.

    Science.gov (United States)

    Briand, G; Dauchot, O

    2016-08-26

    We experimentally study the crystallization of a monolayer of vibrated discs with a built-in polar asymmetry, a model system of active liquids, and contrast it with that of vibrated isotropic discs. Increasing the packing fraction ϕ, the quasicontinuous crystallization reported for isotropic discs is replaced by a transition, or a crossover, towards a "self-melting" crystal. Starting from the liquid phase and increasing the packing fraction, clusters of dense hexagonal-ordered packed discs spontaneously form, melt, split, and merge, leading to a highly intermittent and heterogeneous dynamics. For a packing fraction larger than ϕ^{*}, a few large clusters span the system size. The cluster size distribution is monotonically decreasing for ϕϕ^{*}, and is a power law at the transition. The system is, however, never dynamically arrested. The clusters permanently melt from place to place, forming droplets of an active liquid which rapidly propagate across the system. This self-melting crystalline state subsists up to the highest possible packing fraction, questioning the stability of the crystal for active discs unless it is at ordered close packing. PMID:27610889

  13. The evolution of misaligned accretion discs and spinning black holes

    OpenAIRE

    LODATO G; Pringle, J. E.

    2006-01-01

    In this paper we consider the process of alignment of a spinning black hole and a surrounding misaligned accretion disc. We use a simplified set of equations, that describe the evolution of the system in the case where the propagation of warping disturbances in the accretion disc occurs diffusively, a situation likely to be common in the thin discs in Active Galactic Nuclei (AGN). We also allow the direction of the hole spin to move under the action of the disc torques. In such a way, the evo...

  14. The vibration of rolling discs

    OpenAIRE

    Ferguson, Neil Stuart

    1988-01-01

    The study presented is a fundamental investigation into the vibration of a rolling disc and an analysis of the sound which is then produced by the disc response. In order to characterise the disc's behaviour the free and forced vibration of a thin disc is analysed with the additional conditions which occur in rolling. These conditions include the geometric boundary conditions, the effect of the in-plane load, the change due to rotation of the disc and the effect of contact on the disc which i...

  15. Pseudoenhancement of intervertebral disc herniation

    Energy Technology Data Exchange (ETDEWEB)

    Araki, Y.; Ootani, M.; Furukawa, T.; Tsukaguchi, I. (Dept. of Radiology, Osaka Rosai Hospital (Japan)); Mitomo, M. (Dept. of Radiology, Osaka Univ. Medical School (Japan))

    1992-08-01

    Two patients with intervertebral disc herniation appeared to demonstrate abnormally diffuse and intense enhancement of the disc after intravenous administration of gadolinium-DTPA for MRI. Surgery disclosed a dilated epidural venous plexus in one and vascular granulation tissue in the other, associated with the herniated disc material. The mechanism of this 'pseudoenhancement' of the disc appears to be a partial volume effect of disc material and the adjacent veins or granulation tissue. Pseudoenhancement of a herniated disc should be included in the differential diagnosis of a diffusely enhancing epidural mass. (orig.).

  16. Influence of chemical activation of a 35% hydrogen peroxide bleaching gel on its penetration and efficacy--in vitro study

    OpenAIRE

    Torres, C R G; Wiegand, A.; Sener, B.; Attin, T.

    2010-01-01

    OBJECTIVES: The aim of this study was to evaluate the effects of chemical activation of hydrogen peroxide (HP) gel on colour changes and penetration through the tooth structure. METHODS: One hundred and four bovine incisors were used. One dentine (CD) disc and one enamel-dentine (ED) disc were prepared from each tooth. They were positioned over artificial pulpal chambers and the bleaching was performed with an experimental 35% HP gel. Two control and six experimental groups were prepared. In ...

  17. ACDR 和 ACDF 治疗单节段颈椎间盘突出症的对比分析%Comparative analysis of ACDR and ACDF in the treatment of single segmental cervical intervertebral disc herniation

    Institute of Scientific and Technical Information of China (English)

    黄长安; 李军; 袁文旗; 周立

    2015-01-01

    目的:对比分析颈椎前路椎间盘切除植骨融合术( ACDF)和颈椎人工椎间盘置换术( ACDR)%Objective To compare the effect of anterior cervical discectomy and interbody fusion(ACDF) and artificial cervical disc replacement(ACDR) in the treatment of single segmental cervical disc herniation.Methods A total of 81 patients with single segmental cervical disc herniation were collected in our hospital from January 2010 to June 2014, in which 40 patients received ACDF surgery(fusion group) and other 41 patients underwent ACDR sur-gery(permutation group).The changes of activity were compared between the two groups before and the last follow-up after the surgery.Results There were significant differences in the changes of activity between the two groups at the last time of follow-up after the surgery(P <0.01).For each group, the activity improved at the end of the follow-up compared with that before the surgery(P <0.01).Conclusion Both ACDR and ACDF are effective in the treatment of single segmental cervical disc herniation, which improves the activity of cervical disc herniation.ACDR also makes the surgery adjacent segments of the compensatory activity increased, and therefore may prevent adjacent segment de-generation.

  18. Synthesis and characterization of Gold and Silver nano-particles using different leaf extracts namely Catharanthus roseus, Datura metel and Azadirachta indica and Estimation of antimicrobial activity of silver nano-particles using disc diffusion method

    OpenAIRE

    Sarbjeet Singh Gujral

    2014-01-01

    Objective: synthesis of gold and silver nano-particles using leaf extracts of Catharanthus roseus, Datura metel and Azadirachta indica and Estimation of antimicrobial activity of silver nano-particles using disc diffusion method. Method: Green approach has been utilized for the synthesis of gold and silver nano-particles. Different aqueous plant extracts has been prepared which was then utilized for the biosynthesis of gold and silver nano-particles. Estimation for the synthesis of nano-parti...

  19. Composition of Airy disc

    Institute of Scientific and Technical Information of China (English)

    Guoquan Zhou; Xiuxiang Chu; Jun Zheng

    2008-01-01

    The description of a plane wave diffracted by a circular aperture is directly started from the Maxwell's equations. Based on the vector angular spectrum representation of Maxwell's equations, the diffracted plane wave is decomposed into the TE and TM terms. The analytical TE and TM terms in the far field are presented by stationary phase. As the TE and TM terms are orthogonal to each other in the far field, their sum constitutes the so-called Airy disc pattern. Therefore, this research reveals the composition of Airy disc, which is beneficial to deepen and enhance the recognition of the classical diffraction problem.

  20. 人工椎间盘置换加颈前路椎体次全切减压植骨融合术治疗多节段颈椎病%Artificial Disc Replacement Combined with Anterior Cervical Decompression and Autograft Bone Fusion for the Treatment of Multi-segment Cervical Spondylosis

    Institute of Scientific and Technical Information of China (English)

    廖维峰; 肖晟; 黄象望; 刘向阳; 张毅; 向铁城

    2014-01-01

    [目的]探讨人工椎间盘置换加颈前路椎体次全切减压植骨融合术治疗多节段颈椎病的临床疗效。[方法]湖南省人民医院2008年2月至2012年6月收治的12例多节段颈椎病手术病例,均行人工椎间盘置换加颈前路椎体次全切减压植骨融合术,随访时间为12~18个月,平均随访15.5个月,均摄术前、术后及末次随访时的颈椎正侧位及颈椎过伸过屈位X线片及磁共振检查,观察植骨融合、内固定及人工椎间盘的情况,以JO A评分评价神经功能改善情况。[结果]所有病例内置物无松动、移位,植骨融合时间在3~6个月,平均4.9个月。置换间隙活动度术后1年时为12.5°±5.0°,与术前(12.3°±4.9°)比较无统计学差异(P>0.05)。术前JOA 评分平均为9.3分,术后6个月时平均为16.1分,平均改善率为91.2%。[结论]人工椎间盘置换加颈前路椎体次全切减压植骨融合术治疗多节段颈椎病近期疗效满意,是治疗多节段颈椎病的一种可行方法。%[Objective]To explore the clinical efficacy of cervical artificial disc replacement combined with anterior cervical decompression and autograft bone fusion for the treatment of multi -segment cervical spon-dylosis .[Methods]Twelve patients with multi- segment cervical spondylosis operated in Hunan provincial people's hospital from Feb .2008 to June 2012 underwent cervical artificial disc replacement combined with an-terior cervical decompression and autograft bone fusion .The follow up time was 12~18 months(average 15 .5 months) .Cervical MRI and X-ray films of cervical normal lateral position ,hyperextension and hyperflexion position were performed before and after operation and at the last time of follow up .Bone fusion ,internal fixa-tion and artificial disc were observed .JOA score was used to evaluate the improvement of neurological func-tion .[Results]No loosening and displacement of

  1. The growth of planets by pebble accretion in evolving protoplanetary discs

    CERN Document Server

    Bitsch, Bertram; Johansen, Anders

    2015-01-01

    The formation of planets depends on the underlying protoplanetary disc structure, which influences both the accretion and migration rates of embedded planets. The disc itself evolves on time-scales of several Myr during which both temperature and density profiles change as matter accretes onto the central star. Here we use a detailed model of an evolving disc to determine the growth of planets by pebble accretion and their migration through the disc. Cores that reach their pebble isolation mass accrete gas to finally form giant planets with extensive gas envelopes, while planets that do not reach pebble isolation mass are stranded as ice giants and ice planets containing only minor amounts of gas in their envelopes. Unlike earlier population synthesis models, our model works without any artificial reductions in migration speed and for protoplanetary discs with gas and dust column densities similar to those inferred from observations. We find that in our nominal disc model the emergence of planetary embryos pr...

  2. The evolution of misaligned accretion discs and spinning black holes

    CERN Document Server

    Pringle, J E

    2006-01-01

    In this paper we consider the process of alignment of a spinning black hole and a surrounding misaligned accretion disc. We use a simplified set of equations, that describe the evolution of the system in the case where the propagation of warping disturbances in the accretion disc occurs diffusively, a situation likely to be common in the thin discs in Active Galactic Nuclei (AGN). We also allow the direction of the hole spin to move under the action of the disc torques. In such a way, the evolution of the hole-disc system is computed self-consistently. We consider a number of different situations and we explore the relevant parameter range, by varying the location of the warp radius $R_{\\rm w}$ and the propagation speed of the warp. We find that the dissipation associated with the twisting of the disc results in a large increase in the accretion rate through the disc, so that AGN accreting from a misaligned disc are likely to be significantly more luminous than those accreting from a flat disc. We compute exp...

  3. Edge modes in self-gravitating disc-planet interactions

    CERN Document Server

    Lin, Min-Kai

    2011-01-01

    We study the stability of gaps opened by a giant planet in a self-gravitating protoplanetary disc. We find a linear instability associated with both the self-gravity of the disc and local vortensity maxima which coincide with gap edges. For our models, these edge modes develop and extend to twice the orbital radius of a Saturn mass planet in discs with disc-to-star mass ratio >0.06, corresponding to a Toomre Q < 1.5 at the outer disc boundary. Unlike the local vortex-forming instabilities associated with gap edges in weakly or non-self-gravitating low viscosity discs, the edge modes are global and exist only in sufficiently massive discs, but for the typical viscosity values adopted for protoplanetary discs. Analytic modelling and linear calculations show edge modes may be interpreted as a localised disturbance associated with a gap edge inducing activity in the extended disc, through the launching of density waves excited at Lindblad resonances. Nonlinear hydrodynamic simulations are performed to investig...

  4. Spontaneously disappearing lumbar disc protrusion

    OpenAIRE

    Ushewokunze, Shungu; Abbas, Naeem; Dardis, Ronan; Killeen, Ian

    2008-01-01

    Spontaneous disappearance of a herniated lumbar disc is known to occur. This case study describes a 45-year-old patient whose symptoms of lumbar radiculopathy resolved and follow-up imaging showed complete disappearance of the disc prolapse. This phenomenon strengthens the role of conservative treatment in the management of lumbar disc protrusions.

  5. How do accretion discs break?

    Science.gov (United States)

    Dogan, Suzan

    2016-07-01

    Accretion discs are common in binary systems, and they are often found to be misaligned with respect to the binary orbit. The gravitational torque from a companion induces nodal precession in misaligned disc orbits. In this study, we first calculate whether this precession is strong enough to overcome the internal disc torques communicating angular momentum. We compare the disc precession torque with the disc viscous torque to determine whether the disc should warp or break. For typical parameters precession wins: the disc breaks into distinct planes that precess effectively independently. To check our analytical findings, we perform 3D hydrodynamical numerical simulations using the PHANTOM smoothed particle hydrodynamics code, and confirm that disc breaking is widespread and enhances accretion on to the central object. For some inclinations, the disc goes through strong Kozai cycles. Disc breaking promotes markedly enhanced and variable accretion and potentially produces high-energy particles or radiation through shocks. This would have significant implications for all binary systems: e.g. accretion outbursts in X-ray binaries and fuelling supermassive black hole (SMBH) binaries. The behaviour we have discussed in this work is relevant to a variety of astrophysical systems, for example X-ray binaries, where the disc plane may be tilted by radiation warping, SMBH binaries, where accretion of misaligned gas can create effectively random inclinations and protostellar binaries, where a disc may be misaligned by a variety of effects such as binary capture/exchange, accretion after binary formation.

  6. Tracing Planets in Circumstellar Discs

    Directory of Open Access Journals (Sweden)

    Uribe Ana L.

    2013-04-01

    Full Text Available Planets are assumed to form in circumstellar discs around young stellar objects. The additional gravitational potential of a planet perturbs the disc and leads to characteristic structures, i.e. spiral waves and gaps, in the disc density profile. We perform a large-scale parameter study on the observability of these planet-induced structures in circumstellar discs in the (submm wavelength range for the Atacama Large (SubMillimeter Array (ALMA. On the basis of hydrodynamical and magneto-hydrodynamical simulations of star-disc-planet models we calculate the disc temperature structure and (submm images of these systems. These are used to derive simulated ALMA maps. Because appropriate objects are frequent in the Taurus-Auriga region, we focus on a distance of 140 pc and a declination of ≈ 20°. The explored range of star-disc-planet configurations consists of six hydrodynamical simulations (including magnetic fields and different planet masses, nine disc sizes with outer radii ranging from 9 AU to 225 AU, 15 total disc masses in the range between 2.67·10-7 M⊙ and 4.10·10-2 M⊙, six different central stars and two different grain size distributions, resulting in 10 000 disc models. At almost all scales and in particular down to a scale of a few AU, ALMA is able to trace disc structures induced by planet-disc interaction or the influence of magnetic fields in the wavelength range between 0.4...2.0 mm. In most cases, the optimum angular resolution is limited by the sensitivity of ALMA. However, within the range of typical masses of protoplane tary discs (0.1 M⊙...0.001 M⊙ the disc mass has a minor impact on the observability. At the distance of 140 pc it is possible to resolve discs down to 2.67·10-6 M⊙ and trace gaps in discs with 2.67·10-4 M⊙ with a signal-to-noise ratio greater than three. In general, it is more likely to trace planet-induced gaps in magneto-hydrodynamical disc models, because gaps are wider in the presence of

  7. Intermediate mass black holes in AGN discs - I. Production and growth

    Science.gov (United States)

    McKernan, B.; Ford, K. E. S.; Lyra, W.; Perets, H. B.

    2012-09-01

    Here we propose a mechanism for efficiently growing intermediate mass black holes (IMBH) in discs around supermassive black holes. Stellar mass objects can efficiently agglomerate when facilitated by the gas disc. Stars, compact objects and binaries can migrate, accrete and merge within discs around supermassive black holes. While dynamical heating by cusp stars excites the velocity dispersion of nuclear cluster objects (NCOs) in the disc, gas in the disc damps NCO orbits. If gas damping dominates, NCOs remain in the disc with circularized orbits and large collision cross-sections. IMBH seeds can grow extremely rapidly by collisions with disc NCOs at low relative velocities, allowing for super-Eddington growth rates. Once an IMBH seed has cleared out its feeding zone of disc NCOs, growth of IMBH seeds can become dominated by gas accretion from the active galactic nucleus (AGN) disc. However, the IMBH can migrate in the disc and expand its feeding zone, permitting a super-Eddington accretion rate to continue. Growth of IMBH seeds via NCO collisions is enhanced by a pile-up of migrators. We highlight the remarkable parallel between the growth of IMBH in AGN discs with models of giant planet growth in protoplanetary discs. If an IMBH becomes massive enough it can open a gap in the AGN disc. IMBH migration in AGN discs may stall, allowing them to survive the end of the AGN phase and remain in galactic nuclei. Our proposed mechanisms should be more efficient at growing IMBH in AGN discs than the standard model of IMBH growth in stellar clusters. Dynamical heating of disc NCOs by cusp stars is transferred to the gas in an AGN disc helping to maintain the outer disc against gravitational instability. Model predictions, observational constraints and implications are discussed in a companion paper (Paper II).

  8. Evolution of Protoplanetary Discs with Magnetically Driven Disc Winds

    CERN Document Server

    Suzuki, Takeru K; Morbidelli, Alessandro; Crida, Aurélien; Guillot, Tristan

    2016-01-01

    Aims: We investigate the evolution of protoplanetary discs (PPDs hereafter) with magnetically driven disc winds and viscous heating. Methods: We consider an initially massive disc with ~0.1 Msun to track the evolution from the early stage of PPDs. We solve the time evolution of surface density and temperature by taking into account viscous heating and the loss of the mass and the angular momentum by the disc winds within the framework of a standard alpha model for accretion discs. Our model parameters, turbulent viscosity, disc wind mass loss, and disc wind torque, which are adopted from local magnetohydrodynamical simulations and constrained by the global energetics of the gravitational accretion, largely depends on the physical condition of PPDs, particularly on the evolution of the vertical magnetic flux in weakly ionized PPDs. Results: Although there are still uncertainties concerning the evolution of the vertical magnetic flux remaining, surface densities show a large variety, depending on the combinatio...

  9. Bryan total disc arthroplasty: a replacement disc for cervical disc disease

    OpenAIRE

    Wenger, Markus

    2010-01-01

    Markus Wenger1, Thomas-Marc Markwalder21Neurosurgery, Klinik Beau-Site and Salem-Spital, Berne, Switzerland; 2Attending Neurosurgeon FMH, Private Practice Spine Surgery, Berne-Muri, SwitzerlandAbstract: Total disc arthroplasty is a new option in the treatment of cervical degenerative disc disease. Several types of cervical disc prostheses currently challenge the gold-standard discectomy and fusion procedures. This review describes the Bryan Cervical Disc System and presents the Bryan prosthes...

  10. Artificial Neural Networks for Reducing Computational Effort in Active Truncated Model Testing of Mooring Lines

    DEFF Research Database (Denmark)

    Christiansen, Niels Hørbye; Voie, Per Erlend Torbergsen; Høgsberg, Jan Becker

    2015-01-01

    simultaneously, this method is very demanding in terms of numerical efficiency and computational power. Therefore, this method has not yet proved to be feasible. It has recently been shown how a hybrid method combining classical numerical models and artificial neural networks (ANN) can provide a dramatic...... model. Hence, in principal it is possible to achieve reliable experimental data for much larger water depths than what the actual depth of the test basin would suggest. However, since the computations must be faster than real time, as the numerical simulations and the physical experiment run...... reduction in computational effort when performing time domain simulation of mooring lines. The hybrid method uses a classical numerical model to generate simulation data, which are then subsequently used to train the ANN. After successful training the ANN is able to take over the simulation at a speed two...

  11. Change in the acceleration of artificial satellites during enhanced geomagnetic activity

    Energy Technology Data Exchange (ETDEWEB)

    Chepurnoy, V.N.; Charina, G.A.

    1975-01-01

    Analysis of disturbances in the acceleration (decrease in the period of rotation) of several artificial satellites during the strong magnetic storms of November 1960 showed that the disturbances occurred at the same time all over the world and coincided approximately with the time of the maximum of geomagnetic disturbances. Use of data on variations in the acceleration of satellites with a large balistic coefficient (ratio of transverse cross section to mass) made a more detailed study of acceleration disturbances during magnetic storms possible. It was found that acceleration disturbances lag approximately 5 hours behind the a/sub p/ indexes and their amplitude increases with height. This suggested global heating of the atmosphere above 200 km in proportion with the a/sub p/ index, leading to an increase in intensity and in satellite drag.

  12. Magnetohydrodynamic turbulence in warped accretion discs

    CERN Document Server

    Torkelsson, U; Brandenburg, A; Pringle, J E; Nordlund, A A; Stein, R F; Nordlund, AA.

    2001-01-01

    Warped, precessing accretion discs appear in a range of astrophysical systems, for instance the X-ray binary Her X-1 and in the active nucleus of NGC4258. In a warped accretion disc there are horizontal pressure gradients that drive an epicyclic motion. We have studied the interaction of this epicyclic motion with the magnetohydrodynamic turbulence in numerical simulations. We find that the turbulent stress acting on the epicyclic motion is comparable in size to the stress that drives the accretion, however an important ingredient in the damping of the epicyclic motion is its parametric decay into inertial waves.

  13. Changes in serum thyroid hormone levels and thyroid gland activity of artificially maturing female Japanese eel (Anguilla japonica)

    Institute of Scientific and Technical Information of China (English)

    Qu Xiancheng(曲宪成); Massaki Nagae; Sinji Adachi; Kohei Yamauchi

    2003-01-01

    In order to evaluate the involvement of the thyroid gland in reproduction, thyroid func-tioning was described in female cultivated Japanese eel (Anguilla japonica ) in progressive stages of sex-ual maturation induced by chum salmon pituitary homogenate (SPH) treatment. Serum thyroid hor-mones, thyroxine (T4) and triiodothyronine (T3) were also measured in each stage. Thyroid gland ac-tivity (epithelial cell height) was high before SPH injection (previtellogenic stage), further increasing at the early vitellogenic stage, thereafter decreasing to late vitellogenic and migratory nucleus stages. Theprofiles of both T3 and T4 changed during vitellogenesis, being high during previtellogenic and earlyvitellogenic stages, and subsequently declining, thus mimicking thyroid gland activity. These resultssuggest that the thyroid has relation with eel ovarian development during artificial maturation.

  14. Satellites in discs regulating the accretion luminosity

    CERN Document Server

    Syer, D; Syer, Dave; Clarke, Cathie

    1995-01-01

    We demonstrate, using a simple analytic model, that the presence of a massive satellite can globally modify the structure and emission properties of an accretion disc to which it is tidally coupled. We show, using two levels of numerical approximation, that the analytic model gives reasonable results. The results are applicable to two astrophysical situations. In the case of an active galactic nucleus, we consider the case of a \\sim 10^3\\Msun compact companion to the central black-hole and show that it could modulate the emitted spectrum on a timescale of \\sim10^5 years. In the case of a T Tauri accretion disc, a satellite such as a sub-dwarf or giant planet could modify the disc spectral energy distribution over a substantial fraction of the T Tauri star lifetime.

  15. Determination of activity concentration of natural and artificial radionuclides in sand samples from mediterranean coast of Antalya in Turkey

    International Nuclear Information System (INIS)

    In this paper, we attempt to determine the activity concentration of natural and artificial radionuclides in 37 sand samples from the Mediterranean coast of Antalya in Turkey by using a high purity Germanium (HpGe) detector. 238U, 232Th, 40K and 137Cs activity concentrations, absorbed dose rate, annual effective dose equivalent, radium equivalent activity, external and internal hazard index of sand samples are determined respectively. The average values are 13.43 ± 0.21 Bq/kg, 6.96 ± 0.06 Bq/kg and, 122.46 ± 18.58 Bq/kg, for 238U, 232Th and 40K respectively. Most of the activity concentration values are less than below minimum detection limit for 137Cs. The average values of the absorbed dose rate D (nGy/h), annual effective dose equivalent AEDE(μSv/y), radium equivalent activity Raeq (Bq/kg), external hazard index Hex and internal hazard index Hin are 15.52 nGy/h, 19.03 μSv/y, 32.81 Bq/kg, 0.09 and 0.12 respectively. It is observed that 238U, 232Th, 40K and 137Cs activity concentrations, absorbed dose rate, annual effective dose equivalent, radium equivalent activity are in the limit of the published values, external and internal hazard index values are less than unity.

  16. Wind interactions above accretion discs: a model for broad-line regions and collimated outflow

    International Nuclear Information System (INIS)

    The interaction of a wind from an active galactic nucleus with a Compton-heating-induced wind from an accretion disc is studied. The nuclear wind is taken as initially supersonic and spherically symmetric. The disc wind arises when the disc surface is exposed to a hard and powerful X-ray source. Three classes of interaction are identified in terms of the relation between the pressure on the disc surface and the corresponding thermal and ram pressures in the nuclear wind. (author)

  17. Disrupted in schizophrenia 1 (DISC1) L100P mutants have impaired activity-dependent plasticity in vivo and in vitro.

    Science.gov (United States)

    Tropea, D; Molinos, I; Petit, E; Bellini, S; Nagakura, I; O'Tuathaigh, C; Schorova, L; Mitchell, K J; Waddington, J; Sur, M; Gill, M; Corvin, A P

    2016-01-01

    Major neuropsychiatric disorders are genetically complex but share overlapping etiology. Mice mutant for rare, highly penetrant risk variants can be useful in dissecting the molecular mechanisms involved. The gene disrupted in schizophrenia 1 (DISC1) has been associated with increased risk for neuropsychiatric conditions. Mice mutant for Disc1 display morphological, functional and behavioral deficits that are consistent with impairments observed across these disorders. Here we report that Disc1 L100P mutants are less able to reorganize cortical circuitry in response to stimulation in vivo. Molecular analysis reveals that the mutants have a reduced expression of PSD95 and pCREB in visual cortex and fail to adjust expression of such markers in response to altered stimulation. In vitro analysis shows that mutants have impaired functional reorganization of cortical neurons in response to selected forms of neuronal stimulation, but there is no altered basal expression of synaptic markers. These findings suggest that DISC1 has a critical role in the reorganization of cortical plasticity and that this phenotype becomes evident only under challenge, even at early postnatal stages. This result may represent an important etiological mechanism in the emergence of neuropsychiatric disorders. PMID:26756905

  18. Discs in misaligned binary systems

    CERN Document Server

    Rawiraswattana, Krisada; Goodwin, Simon P

    2016-01-01

    We perform SPH simulations to study precession and changes in alignment between the circumprimary disc and the binary orbit in misaligned binary systems. We find that the precession process can be described by the rigid-disc approximation, where the disc is considered as a rigid body interacting with the binary companion only gravitationally. Precession also causes change in alignment between the rotational axis of the disc and the spin axis of the primary star. This type of alignment is of great important for explaining the origin of spin-orbit misaligned planetary systems. However, we find that the rigid-disc approximation fails to describe changes in alignment between the disc and the binary orbit. This is because the alignment process is a consequence of interactions that involve the fluidity of the disc, such as the tidal interaction and the encounter interaction. Furthermore, simulation results show that there are not only alignment processes, which bring the components towards alignment, but also anti-...

  19. Disc-mass distribution in star-disc encounters

    CERN Document Server

    Steinhausen, M; Pfalzner, S

    2011-01-01

    Investigations of stellar encounters in cluster environments have demonstrated their potential influence on the mass and angular momentum of protoplanetary discs around young stars. In this study it is investigated in how far the initial surface density in the disc surrounding a young star influences the outcome of an encounter. Based on a power-law ansatz for the surface density, $\\Sigma(r) \\propto r^{-p}$, a parameter study of star-disc encounters with different initial disc-mass distributions has been performed using N-body simulations. It is demonstrated that the shape of the disc-mass distribution has a significant impact on the quantity of the disc-mass and angular momentum losses in star-disc encounters. Most sensitive are the results where the outer parts of the disc are perturbed by high-mass stars. By contrast, disc-penetrating encounters lead more or less independently of the disc-mass distribution always to large losses. However, maximum losses are generally obtained for initially flat distributed...

  20. Methodology for optic disc localization

    Directory of Open Access Journals (Sweden)

    Marcos A. Leiva-Vasconcellos

    2014-04-01

    Full Text Available The use of digital images in many areas of society is an activity that has reached a remarkable growth in recent years mainly due to the great development that has occurred in technology around the world. These images have a great use in many branches of medicine because they facilitate the diagnosis by specialists and thus help patients to be diagnosed long before symptoms of the disease begin to manifest. For Ophthalmology, one of the most used images are the digital retinography, If it is used properly will allow the occurrence of eye diseases such as glaucoma and diabetic retinopathy. One of the main elements shown on retinal images are the optic disc, the location and detection is of vital importance for working with different parts of the structure o f the eye. This paper proposes two techniques for locating the optic disc in retinal images based on the combination of multiple filters and applying logical operators. To test the algorithms diaretDB0v11 and DRIVE database were used , as a result of the tests are correctly located the 99.091 % of the images from both repo sitories, and were successfully detected 85 % and 87.143 % of images of DRIVE database and diaretDB0v11 respectively.

  1. Effectiveness of Photogem® activated by LED on the decontamination of artificial carious bovine dentin

    Science.gov (United States)

    Giusti, J. S. M.; Santos-Pinto, L.; Pizzolitto, A. C.; Kurachi, C.; Bagnato, V. S.

    2006-05-01

    The aim of this study was the evaluation of the effectiveness of photodynamic therapy on the decontamination of artificially induced carious bovine dentin, using Photogem® as the photosensitizer agent and an LED device as a light source. Dentin samples obtained from bovine incisors were immersed in sterile broth supplemented by Lactobacillus acidophillus 108 colony formation units (CFU) and Streptococcus mutans 108 CFU. Different concentrations of photosensitizer, PA = 1 mg/ml, PB = 2 mg/ml, and PC = 3 mg/ml, and two fluences, D = 24 J/cm2 and D = 48 J/cm2, were investigated. After CFU counting per milligram of carious dentin and statistical analysis, we observed that the photodynamic therapy (PDT) parameters used were effective for bacterial reduction in the in vitro model under study. The best result was achieved with the application of Photogem® at 2 mg/ml and photoactivated under 24 J/cm2 showing a survival factor of 0.14. At higher photosensitizer concentrations, a higher dark toxicity was observed. We propose a simple mathematical expression for the determination of PDT parameters of photosensitizer concentration and light fluence for different survival factor values. Since LED devices are simpler and cheaper compared to laser systems, it would be interesting to verify their efficacy as a light source in photodynamic therapy for the decontamination of carious dentin.

  2. Is artificial recharge promoting microbial activity and biodegradation processes in groundwater systems?

    Science.gov (United States)

    Barba Ferrer, Carme; Folch, Albert; Gaju, Núria; Martínez-Alonso, Maira; Carrasquilla, Marc; Grau-Martínez, Alba; Sanchez-Vila, Xavier

    2016-04-01

    Managed Artificial Recharge (MAR) represents a strategic tool for managing water resources, especially during scarce periods. On one hand, it can increase water stored in aquifers and extract it when weather conditions do not permit exclusive exploitation of surface resources. On the other, it allows improve water quality due the processes occurring into the soil whereas water crosses vadose zone. Barcelona (Catalonia, Spain) conurbation is suffering significant quantitative and qualitative groundwater disturbances. For this reason, Sant Vicenç MAR system, constituted by a sedimentation and an infiltration pond, was constructed in 2009 as the strategic water management infrastructure. Compared with other MAR facilities, this infiltration pond has a reactive bed formed by organic compost and local material. The objective is to promote different redox states allowing more and different degradation of chemical compounds than regular MAR systems. In previous studies in the site, physical and hydrochemical parameters demonstrated that there was indeed a degradation of different pollutants. However, to go a step further understanding the different biogeochemical processes and the related degradation processes occurring in the system, we studied the existing microbial communities. So, molecular techniques were applied in water and soil samples in two different scenarios; the first one, when the system was fully operating and the second when the system was not operating during some months. We have specifically compared microbial diversity and richness indexes and both cluster dendrograms obtained from DGGEs analysis made in each sampling campaign.

  3. Total disc replacement.

    Science.gov (United States)

    Vital, J-M; Boissière, L

    2014-02-01

    Total disc replacement (TDR) (partial disc replacement will not be described) has been used in the lumbar spine since the 1980s, and more recently in the cervical spine. Although the biomechanical concepts are the same and both are inserted through an anterior approach, lumbar TDR is conventionally indicated for chronic low back pain, whereas cervical TDR is used for soft discal hernia resulting in cervicobrachial neuralgia. The insertion technique must be rigorous, with precise centering in the disc space, taking account of vascular anatomy, which is more complex in the lumbar region, particularly proximally to L5-S1. All of the numerous studies, including prospective randomized comparative trials, have demonstrated non-inferiority to fusion, or even short-term superiority regarding speed of improvement. The main implant-related complication is bridging heterotopic ossification with resulting loss of range of motion and increased rates of adjacent segment degeneration, although with an incidence lower than after arthrodesis. A sufficiently long follow-up, which has not yet been reached, will be necessary to establish definitively an advantage for TDR, particularly in the cervical spine. PMID:24412045

  4. Hourly photosynthetically active radiation estimation in Midwestern United States from artificial neural networks and conventional regressions models

    Science.gov (United States)

    Yu, Xiaolei; Guo, Xulin

    2016-08-01

    The relationship between hourly photosynthetically active radiation (PAR) and the global solar radiation ( R s ) was analyzed from data gathered over 3 years at Bondville, IL, and Sioux Falls, SD, Midwestern USA. These data were used to determine temporal variability of the PAR fraction and its dependence on different sky conditions, which were defined by the clearness index. Meanwhile, models based on artificial neural networks (ANNs) were established for predicting hourly PAR. The performance of the proposed models was compared with four existing conventional regression models in terms of the normalized root mean square error (NRMSE), the coefficient of determination ( r 2), the mean percentage error (MPE), and the relative standard error (RSE). From the overall analysis, it shows that the ANN model can predict PAR accurately, especially for overcast sky and clear sky conditions. Meanwhile, the parameters related to water vapor do not improve the prediction result significantly.

  5. Apsidal precession, disc breaking and viscosity in warped discs

    CERN Document Server

    Nealon, Rebecca; Price, Daniel J; King, Andrew

    2015-01-01

    We demonstrate the importance of general relativistic apsidal precession in warped black hole accretion discs by comparing three - dimensional smoothed particle hydrodynamic simulations in which this effect is first neglected, and then included. If apsidal precession is neglected, we confirm the results of an earlier magnetohydrodynamic simulation which made this assumption, showing that at least in this case the $\\alpha$ viscosity model produces very similar results to those of simulations where angular momentum transport is due to the magnetorotational instability. Including apsidal precession significantly changes the predicted disc evolution. For moderately inclined discs thick enough that tilt is transported by bending waves, we find a disc tilt which is nonzero at the inner disc edge and oscillates with radius, consistent with published analytic results. For larger inclinations we find disc breaking.

  6. Dust dynamics in 2D gravito-turbulent discs

    Science.gov (United States)

    Shi, Ji-Ming; Zhu, Zhaohuan; Stone, James M.; Chiang, Eugene

    2016-06-01

    The dynamics of solid bodies in protoplanetary discs are subject to the properties of any underlying gas turbulence. Turbulence driven by disc self-gravity shows features distinct from those driven by the magnetorotational instability (MRI). We study the dynamics of solids in gravito-turbulent discs with two-dimensional (in the disc plane), hybrid (particle and gas) simulations. Gravito-turbulent discs can exhibit stronger gravitational stirring than MRI-active discs, resulting in greater radial diffusion and larger eccentricities and relative speeds for large particles (those with dimensionless stopping times tstopΩ > 1, where Ω is the orbital frequency). The agglomeration of large particles into planetesimals by pairwise collisions is therefore disfavoured in gravito-turbulent discs. However, the relative speeds of intermediate-size particles (tstopΩ ˜ 1) are significantly reduced as such particles are collected by gas drag and gas gravity into coherent filament-like structures with densities high enough to trigger gravitational collapse. First-generation planetesimals may form via gravitational instability of dust in marginally gravitationally unstable gas discs.

  7. Study of HPGe detector peak efficiency by disc source

    International Nuclear Information System (INIS)

    Background: Calibrating the detection efficiency accurately is the key process to the disc filter sample activity detected by High Purity Germanium (HPGe) gamma spectrometer, and the diameter of the disc filter source is varied with the specification of the sampler filter. Purpose: To study further the relation between detection efficiency and the source size, the HPGe detector peak efficiency (relative detective efficiency is 60%) was performed for disc sources with diameters of Ø24 mm, Ø80 mm and Ø90 mm, respectively. Methods: The efficiency and the solid angle for disc source with diameter ranging Ø40-160 mm were simulated using the MCNP and the Geant4. Results: The result shows that the detecting efficiency of three sources is consistent, and the efficiency gradually decreases with the increasing size of the disc source with diameter greater than Ø90 mm. Conclusion: The efficiency for disc sources with diameter less than Ø90 mm is directly calibrated by the standard point sources, while for disc sources with diameter larger than Ø90 mm which is needed to be calibrated by the standard disc sources. (authors)

  8. Planet-Disc Interactions in Fully Radiative Discs

    OpenAIRE

    Bitsch, Bertram

    2011-01-01

    In this dissertation the movement of planets in accretion discs surrounding young stars is investigated. The accretion disc surrounds a protostar, which in turn is created due to the gravitational collapse of an interstellar gas cloud. In this accretion disc, small dust particles can grow to larger objects with a size of up to a few kilometers. These objects are called planetesimals. Through collisions, these planetesimals can grow further until they reach the size of a protoplanet. The proto...

  9. Disc-planet interactions in sub-keplerian discs

    OpenAIRE

    Paardekooper, S.-J.

    2009-01-01

    One class of protoplanetary disc models, the X-wind model, predicts strongly subkeplerian orbital gas velocities, a configuration that can be sustained by magnetic tension. We investigate disc-planet interactions in these subkeplerian discs, focusing on orbital migration for low-mass planets and gap formation for high-mass planets. We use linear calculations and nonlinear hydrodynamical simulations to measure the torque and look at gap formation. In both cases, the subkeplerian nature of the ...

  10. Optimizing the conditions for in vitro maturation and artificial activation of sika deer (Cervus nippon hortulorum) oocytes.

    Science.gov (United States)

    Yin, Y; Tang, L; Zhang, P; Kong, D; Wang, Z; Guan, J; Song, G; Tang, B; Li, Z

    2013-02-01

    With the goal of establishing experimental protocols for cloning sika deer, various conditions for in vitro maturation (IVM) and artificial activation of sika deer oocytes were examined. In vitro maturation was evaluated in seven different culture media. The highest rate of oocyte maturation was 75.4% in 10 μg/ml follicle-stimulating hormone (FSH), 1 μg/ml LH, 0.2 mm cysteamine and 50 ng/ml epidermal growth factor (EGF) after 24 h of IVM. The efficiency after 24 h of IVM did not differ significantly (p > 0.05) from that observed after 20 h. Cysteamine (0.2 mm) significantly increased the maturation rates after 20 h (from 59.1% to 67.2%, p sika deer oocytes to the blastocyst stage (32.4%). Our results indicate that in vitro matured sika deer oocytes are good candidates for parthenogenetic activation and that chemical treatment is needed for relatively efficient activation of the oocytes. These optimized conditions for IVM and parthenogenetic activation may be useful for efforts to restore populations of the endangered sika deer using the somatic cell nuclear transfer technique. PMID:22458270

  11. Edge-on thick discs

    Science.gov (United States)

    Kasparova, A.; Katkov, I.; Chilingarian, I.; Silchenko, O.; Moiseev, A.; Borisov, S.

    2016-06-01

    Although thick stellar discs are detected in nearly all edge-on disc galaxies, their formation scenarios still remain a matter of debate. Due to observational difficulties, there is a lack of information about their stellar populations. Using the Russian 6-m telescope BTA we collected deep spectra of thick discs in three edge-on early-type disc galaxies located in different environments: NGC4111 in a dense group, NGC4710 in the Virgo cluster, and NGC5422 in a sparse group. We see intermediate age (4 ‑ 5 Gyr) metal rich ([Fe/H] ~ ‑0.2 ‑ 0.0 dex) stellar populations in NGC4111 and NGC4710. On the other hand, NGC5422 does not harbour young stars, its only disc is thick and old (10 Gyr) and its α-element abundance suggests a long formation epoch implying its formation at high redshift. Our results prove the diversity of thick disc formation scenarios.

  12. Determination of activity concentration of natural and artificial radionuclides in sand samples from mediterranean coast of Antalya in Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Eke, Canel [Akdeniz Univ., Div. of Physics Education, Antalya (Turkey); Akdeniz Univ., Nuekleer Bilimler Uygulama ve Arastirma Merkezi, Antalya (Turkey); Boztosun, Ismail [Akdeniz Univ., Nuekleer Bilimler Uygulama ve Arastirma Merkezi, Antalya (Turkey); Akdeniz Univ., Dept. of Physics, Antalya (Turkey)

    2015-07-15

    In this paper, we attempt to determine the activity concentration of natural and artificial radionuclides in 37 sand samples from the Mediterranean coast of Antalya in Turkey by using a high purity Germanium (HpGe) detector. {sup 238}U, {sup 232}Th, {sup 40}K and {sup 137}Cs activity concentrations, absorbed dose rate, annual effective dose equivalent, radium equivalent activity, external and internal hazard index of sand samples are determined respectively. The average values are 13.43 ± 0.21 Bq/kg, 6.96 ± 0.06 Bq/kg and, 122.46 ± 18.58 Bq/kg, for {sup 238}U, {sup 232}Th and {sup 40}K respectively. Most of the activity concentration values are less than below minimum detection limit for {sup 137}Cs. The average values of the absorbed dose rate D (nGy/h), annual effective dose equivalent AEDE(μSv/y), radium equivalent activity Ra{sub eq} (Bq/kg), external hazard index H{sub ex} and internal hazard index H{sub in} are 15.52 nGy/h, 19.03 μSv/y, 32.81 Bq/kg, 0.09 and 0.12 respectively. It is observed that {sup 238}U, {sup 232}Th, {sup 40}K and {sup 137}Cs activity concentrations, absorbed dose rate, annual effective dose equivalent, radium equivalent activity are in the limit of the published values, external and internal hazard index values are less than unity.

  13. CT discography for cervical soft disc hernia

    International Nuclear Information System (INIS)

    In this study the effectiveness of computed tomographic discography (CTD) in diagnosing cervical soft disc hernia was evaluated. Twenty-five interververtebral discs of 15 cases with cervical soft disc hernia were examined with a discography and then a CT scan. Results of the CT scan were as follows: three discs were protruded, 12 discs were prolapsed, 6 discs were extruded, and 4 discs were sequestrated. The findings were helpful in determining the location of soft disc hernians between the median and posterolateral discs. They were also valuable in classifying types of hernians and surgical aproaches. (author)

  14. Artificial blood

    Directory of Open Access Journals (Sweden)

    Sarkar Suman

    2008-01-01

    Full Text Available Artificial blood is a product made to act as a substitute for red blood cells. While true blood serves many different functions, artificial blood is designed for the sole purpose of transporting oxygen and carbon dioxide throughout the body. Depending on the type of artificial blood, it can be produced in different ways using synthetic production, chemical isolation, or recombinant biochemical technology. Development of the first blood substitutes dates back to the early 1600s, and the search for the ideal blood substitute continues. Various manufacturers have products in clinical trials; however, no truly safe and effective artificial blood product is currently marketed. It is anticipated that when an artificial blood product is available, it will have annual sales of over $7.6 billion in the United States alone.

  15. Application of artificial neural network in precise prediction of cement elements percentages based on the neutron activation analysis

    Science.gov (United States)

    Eftekhari Zadeh, E.; Feghhi, S. A. H.; Roshani, G. H.; Rezaei, A.

    2016-05-01

    Due to variation of neutron energy spectrum in the target sample during the activation process and to peak overlapping caused by the Compton effect with gamma radiations emitted from activated elements, which results in background changes and consequently complex gamma spectrum during the measurement process, quantitative analysis will ultimately be problematic. Since there is no simple analytical correlation between peaks' counts with elements' concentrations, an artificial neural network for analyzing spectra can be a helpful tool. This work describes a study on the application of a neural network to determine the percentages of cement elements (mainly Ca, Si, Al, and Fe) using the neutron capture delayed gamma-ray spectra of the substance emitted by the activated nuclei as patterns which were simulated via the Monte Carlo N-particle transport code, version 2.7. The Radial Basis Function (RBF) network is developed with four specific peaks related to Ca, Si, Al and Fe, which were extracted as inputs. The proposed RBF model is developed and trained with MATLAB 7.8 software. To obtain the optimal RBF model, several structures have been constructed and tested. The comparison between simulated and predicted values using the proposed RBF model shows that there is a good agreement between them.

  16. Prediction of activity coefficients at infinite dilution for organic solutes in ionic liquids by artificial neural network

    International Nuclear Information System (INIS)

    To our knowledge, this work illustrates for the first time the ability of artificial neural network (ANN) to predict activity coefficients at infinite dilution for organic solutes in ionic liquids (ILs). Activity coefficient at infinite dilution (γ∞) is a useful parameter which can be used for the selection of effective solvent in the separation processes. Using a multi-layer feed-forward network with Levenberg-Marquardt optimization algorithm, the resulting ANN model generated activity coefficient at infinite dilution data over a temperature range of 298 to 363 K. The unavailable input data concerning softness (S) of organic compounds (solutes) and dipole moment (μ) of ionic liquids were calculated using GAMESS suites of quantum chemistry programs. The resulting ANN model and its validation are based on the investigation of up to 24 structurally different organic compounds (alkanes, alkenes, alkynes, cycloalkanes, aromatics, and alcohols) in 16 common imidazolium-based ionic liquids, at different temperatures within the range of 298 to 363 K (i.e. a total number of 914 γSolute∞ for each IL data point). The results show a satisfactory agreement between the predicted ANN and experimental data, where, the root mean square error (RMSE) and the determination coefficient (R2) of the designed neural network were found to be 0.103, 0.996 for training data and 0.128, 0.994 for testing data, respectively.

  17. Evaluation of Near/Far Field and Directivity of Ultrasonic Transducer for Turbine Rotor Disc

    International Nuclear Information System (INIS)

    Near/far field length and directivity of transducers were investigated for the improvement and evaluation of the detectability of flaws in a disc. The reference block is fabricated for the disc of stage 6 in Yonggwang unit 1. The near/far field and directivity of an ultrasonic transducer with the center frequency of 5MHz were calculated for the inspection of the disc. These values showed good agreements with the experimental results. In the system composed of a wedge and a disc, those are evaluated theoretically and experimentally for the specimen with the artificial flaws of the size 2mm and 4mm and an ultrasonic transducer with the center frequency 5MHz and diameter 0.5 inch. The detectability of keyway-flaw and detectable region for inspection were evaluated by using both tangential 45 .deg. and 90 .deg. transducers located at the distance of 53mm and 75mm from the disc hub, respectively

  18. Development of an Ultrasonic Inspection Technique for LP Turbine Rotor Disc

    International Nuclear Information System (INIS)

    Turbine rotor disc consists of disc, bore, keyway, hub, and rim in which the typical defects are located. And these part of disc has very complicated geometry, therefore proper transducer selection, wedge design, fabrication, classification and evaluation of the signal identification are required. In this research, test block with the artificial flaws at keyway and boresurface parts have been used in order to establish the ultrasonic inspection technique for flaw detectability on disc. The analysis of the signals from the test blocks was performed. The wedges were designed according to the curvature from the discs. All the ultrasonic signals were collected and identified for evaluation. The ultrasonic inspection technique for the flaw-detection was established from this research. And it is proved that the result of this research can be applicable in the field inspection

  19. An artificial di-iron oxo-protein with phenol oxidase activity

    Science.gov (United States)

    Faiella, Marina; Andreozzi, Concetta; de Rosales, Rafael Torres Martin; Pavone, Vincenzo; Maglio, Ornella; Nastri, Flavia; DeGrado, William F; Lombardi, Angela

    2013-01-01

    Here we report the de novo design and NMR structure of a four-helical bundle di-iron protein with phenol oxidase activity. The introduction of the cofactor-binding and phenol-binding sites required the incorporation of residues that were detrimental to the free energy of folding of the protein. Sufficient stability was, however, obtained by optimizing the sequence of a loop distant from the active site. PMID:19915535

  20. An artificial di-iron oxo-protein with phenol oxidase activity

    OpenAIRE

    Faiella, Marina; Andreozzi, Concetta; de Rosales, Rafael Torres Martin; Pavone, Vincenzo; Maglio, Ornella; Nastri, Flavia; DeGrado, William F.; Lombardi, Angela

    2009-01-01

    Here we report the de novo design and NMR structure of a four-helical bundle di-iron protein with phenol oxidase activity. The introduction of the cofactor-binding and phenol-binding sites required the incorporation of residues that were detrimental to the free energy of folding of the protein. Sufficient stability was, however, obtained by optimizing the sequence of a loop distant from the active site.

  1. The gravo-magneto disc instability with a viscous dead zone

    CERN Document Server

    Martin, Rebecca G

    2013-01-01

    We consider the evolution of accretion discs that contain some turbulence within a disc dead zone, a region about the disc midplane of a disc that is not sufficiently ionised for the magneto-rotational instability (MRI) to drive turbulence. In particular, we determine whether additional sources of turbulence within a dead zone are capable of suppressing gravo-magneto (GM) disc outbursts that arise from a rapid transition from gravitationally produced to MRI produced turbulence. With viscous $\\alpha$ disc models we consider two mechanisms that may drive turbulence within the dead zone. First, we examine a constant $\\alpha$ parameter within the dead zone. This may be applicable to hydrodynamical instability, such as baroclinic instability, where the turbulence level is independent of the MRI active surface layer properties. In this case, we find that the disc will not become stable to the outbursts unless the dead zone turbulent viscosity is comparable to that in the MRI active surface layers. Under such condit...

  2. Relativistic Disc lines

    CERN Document Server

    Fabian, A C; Parker, M L

    2014-01-01

    Broad emission lines, particularly broad iron-K lines, are now commonly seen in the X-ray spectra of luminous AGN and Galactic black hole binaries. Sensitive NuSTAR spectra over the energy range of 3-78 keV and high frequency reverberation spectra now confirm that these are relativistic disc lines produced by coronal irradiation of the innermost accretion flow around rapidly spinning black holes. General relativistic effects are essential in explaining the observations. Recent results are briefly reviewed here.

  3. Low back pain and degenerative disc disease

    Directory of Open Access Journals (Sweden)

    Jandrić Slavica

    2006-01-01

    Full Text Available Introduction. Various clinical conditions can cause low back pain, and in most cases it is of a degenerative origin. Degenerative disc disease is a common condition which affects young to middle-aged men and women equally. Changes in the mechanical properties of the disc lead to degenerative arthritis in the intervertebral joints, osteophytes, and narrowing the intervertebral foramen or the spinal canal. Pathophysiology. Degenerative cascade, described by Kirkaldy-Willis, is the widely accepted pathophysiologic model describing the degenerative process as it affects the lumbar spine in 3 phases. Diagnosis. There are two forms of low back pain secondary to degenerative disc disease: a lumbalgia and b lumbar radiculopathy. Limitation of movement, problems with balance, pain, loss of reflexes in the extremities, muscle weakness, loss of sensation or other signs of neurological damage can be found on physical examination. For accurate diagnosis, it is often necessary to combine clinical examination and sophisticated technology. Treatment. Coservative treatment consists of rest, physical therapy, pharmacological therapy and injection therapy. Physical rehabilitation with active patient participation is a key approach to treatment of patients with discogenic pain. Physical therapy, occupational therapy and kinesitherapy are important for improving muscle strength, endurance, and flexibility. Disc surgery is performed if surgical intervention is required. .

  4. Reconstructing the star formation history of the Milky Way disc(s) from chemical abundances

    CERN Document Server

    Snaith, O; Di Matteo, P; Lehnert, M D; Combes, F; Katz, D; Gómez, A

    2014-01-01

    We develop a chemical evolution model in order to study the star formation history of the Milky Way. Our model assumes that the Milky Way is formed from a closed box-like system in the inner regions, while the outer parts of the disc experience some accretion. Unlike the usual procedure, we do not fix the star formation prescription (e.g. Kennicutt law) in order to reproduce the chemical abundance trends. Instead, we fit the abundance trends with age in order to recover the star formation history of the Galaxy. Our method enables one to recover with unprecedented accuracy the star formation history of the Milky Way in the first Gyrs, in both the inner (R9-10kpc) discs as sampled in the solar vicinity. We show that, in the inner disc, half of the stellar mass formed during the thick disc phase, in the first 4-5 Gyr. This phase was followed by a significant dip in the star formation activity (at 8-9 Gyr) and a period of roughly constant lower level star formation for the remaining 8 Gyr. The thick disc phase ha...

  5. Three-dimentional simulation of flow-induced platelet activation in artificial heart valves

    Science.gov (United States)

    Hedayat, Mohammadali; Asgharzadeh, Hafez; Borazjani, Iman

    2015-11-01

    Since the advent of heart valve, several valve types such as mechanical and bio-prosthetic valves have been designed. Mechanical Heart Valves (MHV) are durable but suffer from thromboembolic complications that caused by shear-induced platelet activation near the valve region. Bio-prosthetic Heart Valves (BHV) are known for better hemodynamics. However, they usually have a short average life time. Realistic simulations of heart valves in combination with platelet activation models can lead to a better understanding of the potential risk of thrombus formation in such devices. In this study, an Eulerian approach is developed to calculate the platelet activation in three-dimensional simulations of flow through MHV and BHV using a parallel overset-curvilinear immersed boundary technique. A curvilinear body-fitted grid is used for the flow simulation through the anatomic aorta, while the sharp-interface immersed boundary method is used for simulation of the Left Ventricle (LV) with prescribed motion. In addition, dynamics of valves were calculated numerically using under-relaxed strong-coupling algorithm. Finally, the platelet activation results for BMV and MHV are compared with each other.

  6. Pattern formation in artificially activated ectoderm (Rana pipiens and Ambystoma punctatum)

    NARCIS (Netherlands)

    Nieuwkoop, P.D.

    1963-01-01

    Presumptive ectoneuroderm of late blastulae or early gastrulae of Rana pipiens was partially activated by short-lasting disaggregation in Ca-free Holtfreter or Niu-Twitty solutions and subsequent reaggregation in normal solutions. The explants usually became dumbbell shaped and consisted respectivel

  7. Percutaneous laser disc decompression for cervical disc herniation

    International Nuclear Information System (INIS)

    Objective: To discuss the clinical application of percutaneous laser disc decompression (PLDD) in the treatment of cervical disc herniation. Methods: The region between anterolateral cervical visceral sheath and carotid sheath was used as puncture access. Under C-arm fluoroscopic monitoring, the puncture needle was inserted to the cervical intervertebral space center, then, the photofiber was implanted in PLDD was performed in 32 patients of cervical disc herniation by using SLT30 semiconductor laser device with the laser output of 500-1 000 J. Results: The effective rate was 87.5%. No infection or serious complications occurred. Conclusion: Percutaneous laser disc decompression is a safe, effective and less invasive treatment for cervical disc herniation. (authors)

  8. Artificial intelligence

    CERN Document Server

    Ennals, J R

    1987-01-01

    Artificial Intelligence: State of the Art Report is a two-part report consisting of the invited papers and the analysis. The editor first gives an introduction to the invited papers before presenting each paper and the analysis, and then concludes with the list of references related to the study. The invited papers explore the various aspects of artificial intelligence. The analysis part assesses the major advances in artificial intelligence and provides a balanced analysis of the state of the art in this field. The Bibliography compiles the most important published material on the subject of

  9. Artificial urushi.

    Science.gov (United States)

    Kobayashi, S; Uyama, H; Ikeda, R

    2001-11-19

    A new concept for the design and laccase-catalyzed preparation of "artificial urushi" from new urushiol analogues is described. The curing proceeded under mild reaction conditions to produce the very hard cross-linked film (artificial urushi) with a high gloss surface. A new cross-linkable polyphenol was synthesized by oxidative polymerization of cardanol, a phenol derivative from cashew-nut-shell liquid, by enzyme-related catalysts. The polyphenol was readily cured to produce the film (also artificial urushi) showing excellent dynamic viscoelasticity. PMID:11763444

  10. Application of artificial neural networks for the soil moisture retrieval from active and passive microwave spaceborne sensors

    Science.gov (United States)

    Santi, Emanuele; Paloscia, Simonetta; Pettinato, Simone; Fontanelli, Giacomo

    2016-06-01

    Among the algorithms used for the retrieval of SMC from microwave sensors (both active, such as Synthetic Aperture Radar-SAR, and passive, radiometers), the artificial neural networks (ANN) represent the best compromise between accuracy and computation speed. ANN based algorithms have been developed at IFAC, and adapted to several radar and radiometric satellite sensors, in order to generate SMC products at a resolution varying from hundreds of meters to tens of kilometers according to the spatial scale of each sensor. These algorithms, which are based on the ANN techniques for inverting theoretical and semi-empirical models, have been adapted to the C- to Ka- band acquisitions from spaceborne radiometers (AMSR-E/AMSR2), SAR (Envisat/ASAR, Cosmo-SkyMed) and real aperture radar (MetOP ASCAT). Large datasets of co-located satellite acquisitions and direct SMC measurements on several test sites worldwide have been used along with simulations derived from forward electromagnetic models for setting up, training and validating these algorithms. An overall quality assessment of the obtained results in terms of accuracy and computational cost was carried out, and the main advantages and limitations for an operational use of these algorithms were evaluated. This technique allowed the retrieval of SMC from both active and passive satellite systems, with accuracy values of about 0.05 m3/m3 of SMC or better, thus making these applications compliant with the usual accuracy requirements for SMC products from space.

  11. 46 CFR 64.61 - Rupture disc.

    Science.gov (United States)

    2010-10-01

    ... SYSTEMS Pressure Relief Devices and Vacuum Relief Devices for MPTs § 64.61 Rupture disc. If a rupture disc is the only pressure relief device on the tank, the rupture disc must— (a) Rupture at a pressure...

  12. A Modified Active Appearance Model Based on an Adaptive Artificial Bee Colony

    Directory of Open Access Journals (Sweden)

    Mohammed Hasan Abdulameer

    2014-01-01

    Full Text Available Active appearance model (AAM is one of the most popular model-based approaches that have been extensively used to extract features by highly accurate modeling of human faces under various physical and environmental circumstances. However, in such active appearance model, fitting the model with original image is a challenging task. State of the art shows that optimization method is applicable to resolve this problem. However, another common problem is applying optimization. Hence, in this paper we propose an AAM based face recognition technique, which is capable of resolving the fitting problem of AAM by introducing a new adaptive ABC algorithm. The adaptation increases the efficiency of fitting as against the conventional ABC algorithm. We have used three datasets: CASIA dataset, property 2.5D face dataset, and UBIRIS v1 images dataset in our experiments. The results have revealed that the proposed face recognition technique has performed effectively, in terms of accuracy of face recognition.

  13. Carbonic anhydrase immobilized on hollow fiber membranes using glutaraldehyde activated chitosan for artificial lung applications

    OpenAIRE

    Kimmel, J. D.; Arazawa, D. T.; Ye, S.-H.; Shankarraman, V; Wagner, W. R.; Federspiel, W. J.

    2013-01-01

    Extracorporeal CO2 removal from circulating blood is a promising therapeutic modality for the treatment of acute respiratory failure. The enzyme carbonic anhydrase accelerates CO2 removal within gas exchange devices by locally catalyzing HCO3− into gaseous CO2 within the blood. In this work, we covalently immobilized carbonic anhydrase on the surface of polypropylene hollow fiber membranes using glutaraldehyde activated chitosan tethering to amplify the density of reactive amine functional gr...

  14. Chemonucleolysis of lumbar disc herniation

    International Nuclear Information System (INIS)

    Chemonucleolysis is an advantageous alternative to surgical treatment of lumbar disc herniation. To achieve the best results the indications must be strictly observed and the procedure itself must be technically perfect. In these circumstances a rapid, non-invasive and less expensive treatment of lumbar disc herniation is possible. (orig.)

  15. Artificial Reefs

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — An artificial reef is a human-made underwater structure, typically built to promote marine life in areas with a generally featureless bottom, control erosion, block...

  16. Activation of TonEBP by Calcium Controls β1,3-Glucuronosyltransferase-I Expression, a Key Regulator of Glycosaminoglycan Synthesis in Cells of the Intervertebral Disc*

    OpenAIRE

    Hiyama, Akihiko; Gajghate, Sachin; Sakai, Daisuke; Mochida, Joji; Shapiro, Irving M.; Risbud, Makarand V.

    2009-01-01

    The goal of this investigation was to study the expression and regulation of β1,3-Glucuronosyltransferase-I (GlcAT-I), a key enzyme regulating GAG synthesis in cells of the intervertebral disc. There was a robust expression of GlcAT-I in the nucleus pulposus in vivo. Treatment with the calcium ionophore ionomycin resulted in increased GlcAT-I expression, whereas GlcAT-I promoter constructs lacking TonE site or a mutant TonE were unresponsive to the ionophore. Experimen...

  17. Natural - synthetic - artificial!

    DEFF Research Database (Denmark)

    Nielsen, Peter E

    2010-01-01

    The terms "natural," "synthetic" and "artificial" are discussed in relation to synthetic and artificial chromosomes and genomes, synthetic and artificial cells and artificial life.......The terms "natural," "synthetic" and "artificial" are discussed in relation to synthetic and artificial chromosomes and genomes, synthetic and artificial cells and artificial life....

  18. Central Spindle Self-Organization and Cytokinesis in Artificially Activated Sea Urchin Eggs.

    Science.gov (United States)

    Henson, John H; Buckley, Mary W; Yeterian, Mesrob; Weeks, Richard M; Simerly, Calvin R; Shuster, Charles B

    2016-04-01

    The ability of microtubules of the mitotic apparatus to control the positioning and initiation of the cleavage furrow during cytokinesis was first established from studies on early echinoderm embryos. However, the identity of the microtubule population that imparts cytokinetic signaling is unclear. The two main--and not necessarily mutually exclusive--candidates are the central spindle and the astral rays. In the present study, we examined cytokinesis in ammonia-activated sea urchin eggs, which lack paternally derived centrosomes and undergo mitosis mediated by unusual anastral, bipolar mini-spindles. Live cell imaging and immunolabeling for microtubules and the centralspindlin constituent and kinesin-related protein, MKLP1, demonstrated that furrowing in ammonia-activated eggs was associated with aligned arrays of centralspindlin-linked, opposed bundles of antiparallel microtubules. These autonomous, zipper-like arrays were not associated with a mitotic apparatus, but did possess characteristics similar to the central spindle region of control, fertilized embryos. Our results highlight the self-organizing nature of the central spindle region and its ability to induce cytokinesis-like furrowing, even in the absence of a complete mitotic apparatus. PMID:27132131

  19. Application of artificial neural networks to a nanoflare model of active region emission line radiance

    CERN Document Server

    Bazarghan, M; Innes, D E; Karami, E; Solanki, S K

    2008-01-01

    Context. Nanoflares are small impulsive bursts of energy that blend with and possibly make up much of the solar background emission. Determining their frequency and energy input is central to understanding the heating of the solar corona. One method is to extrapolate the energy frequency distribution of larger individually observed flares to lower energies. Only if the power law exponent is greater than 2, is it considered possible that nanoflares contribute significantly to the energy input. Aims. Time sequences of ultraviolet line radiances observed in the corona of an active region are modelled with the aim of determining the power law exponent of the nanoflare energy distribution. Methods. A simple nanoflare model based on three key parameters (the flare rate, the flare duration time, and the power law exponent of the flare energy frequency distribution) is used to simulate emission line radiances from the ions Fe XIX, Ca XIII, and Si iii, observed by SUMER in the corona of an active region as it rotates ...

  20. Disc-based microarrays: principles and analytical applications.

    Science.gov (United States)

    Morais, Sergi; Puchades, Rosa; Maquieira, Ángel

    2016-07-01

    The idea of using disk drives to monitor molecular biorecognition events on regular optical discs has received considerable attention during the last decade. CDs, DVDs, Blu-ray discs and other new optical discs are universal and versatile supports with the potential for development of protein and DNA microarrays. Besides, standard disk drives incorporated in personal computers can be used as compact and affordable optical reading devices. Consequently, a CD technology, resulting from the audio-video industry, has been used to develop analytical applications in health care, environmental monitoring, food safety and quality assurance. The review presents and critically evaluates the current state of the art of disc-based microarrays with illustrative examples, including past, current and future developments. Special mention is made of the analytical developments that use either chemically activated or raw standard CDs where proteins, oligonucleotides, peptides, haptens or other biological probes are immobilized. The discs are also used to perform the assays and must maintain their readability with standard optical drives. The concept and principle of evolving disc-based microarrays and the evolution of disk drives as optical detectors are also described. The review concludes with the most relevant uses ordered chronologically to provide an overview of the progress of CD technology applications in the life sciences. Also, it provides a selection of important references to the current literature. Graphical Abstract High density disc-based microarrays. PMID:26922341

  1. Active vibration control of flexible cantilever plates using piezoelectric materials and artificial neural networks

    Science.gov (United States)

    Abdeljaber, Osama; Avci, Onur; Inman, Daniel J.

    2016-02-01

    The study presented in this paper introduces a new intelligent methodology to mitigate the vibration response of flexible cantilever plates. The use of the piezoelectric sensor/actuator pairs for active control of plates is discussed. An intelligent neural network based controller is designed to control the optimal voltage applied on the piezoelectric patches. The control technique utilizes a neurocontroller along with a Kalman Filter to compute the appropriate actuator command. The neurocontroller is trained based on an algorithm that incorporates a set of emulator neural networks which are also trained to predict the future response of the cantilever plate. Then, the neurocontroller is evaluated by comparing the uncontrolled and controlled responses under several types of dynamic excitations. It is observed that the neurocontroller reduced the vibration response of the flexible cantilever plate significantly; the results demonstrated the success and robustness of the neurocontroller independent of the type and distribution of the excitation force.

  2. Artificial Induction of Twinning by an Active Immunization of Beef Cows Against Inhibin Partially Purified from Porcine Seminal Plasma

    Institute of Scientific and Technical Information of China (English)

    YANG Li-guo; ZHANG Ju-nong; WANG Jin-rong; YE Rong; SANG Run-zi; NIU Shu-li; LIU Cheng-hai

    2002-01-01

    Two hundred and seventy multiparous Chinese Yellow cattle (beef) were selected at 1 to 3months postpartum and divided into three groups (90 cows for each). Animals were given both a primary and booster immunizations with a total dose of 3 mg (Group Th) or 1.5 mg (Group Tl) of seminal preparation containing inhibin activity, emulsified with Freund's complete adjuvant and incomplete adjuvant (for booster), at 3 or 4-week intervals. Other cows were treated with the same volume of seminal preparation without inhibin activity as procedures mentioned above to serve as a control (Group C). Artificial inseminations were given twice at 8 - 12 h intervals when the cow was in heat. Jugular venous blood samples were collected from each cow and used to assay the presence of antibody against seminal preparation by double-diffusion in agar precipitation test and to detect the titer of inhibin antibody by an ELISA method. Data from 247 cows showed that 83.9% (73/87) of cows were in estrus and ovulated 89 ova altogether, of which 19 cows ovulated twin ova and 15 cows produced twins in Group Th (n = 87). However, only 61.1% (44/72) of cows in Group Tl (n=72) and 62.5% (55/88) of cows in Group C were in estrus and ovulated 46 and 52 ova altogether respectively.The ovulation rate (1.27 + 0.03), calving rate ( 126.3% ) and twinning rate (26.3%) in Group Th were greater than those in Groups Tl or C (P<0.01). Furthermore, the ovulation rate was associated with antibody titer in sera of immunized animals (r = 0.7507, P <0.01). These results indicate that active immunization of postpartum cows against inhibin purified from porcine seminal plasma may increase the ovulation rate and induce twinning, suggesting the potential to develop a method to improve fertility in cows.

  3. On disc-planet interactions in sub-keplerian discs

    CERN Document Server

    Paardekooper, S -J

    2009-01-01

    One class of protoplanetary disc models, the X-wind model, predicts strongly subkeplerian orbital gas velocities, a configuration which can be sustained by magnetic tension. We investigate disc-planet interactions in these subkeplerian discs, focusing on orbital migration for low-mass planets and gap formation for high-mass planets. We use linear calculations and non-linear hydrodynamical simulations to measure the torque and look at gap formation. In both cases, the subkeplerian nature of the disc is treated as a fixed external constraint. We show that, depending on the degree to which the disc is subkeplerian, the torque on low-mass planets varies between the usual Type I torque and the one-sided outer Lindblad torque, which is also negative but an order of magnitude larger. In strongly subkeplerian discs, corotation effects can be ignored, making migration fast and inward. Gap formation near the planet's orbit is more difficult in such discs, since there are no resonances close to the planet accommodating ...

  4. Comparison of pre- and postimplantation development following the application of three artificial activating stimuli in a mouse model with round-headed sperm cells deficient for oocyte activation

    DEFF Research Database (Denmark)

    Vanden Meerschaut, Frauke; Nikiforaki, D.; De Roo, C.;

    2013-01-01

    with fertile controls to assess their fertility. MAIN RESULTS AND THE ROLE OF CHANCE The percentage of oocytes showing calcium rises as well as the number of calcium rises per oscillating oocyte were significantly lower in the wobbler group when compared with the WT group (9.3 versus 96% and 2...... significantly lower at weeks 2, 3 and 4 when compared with female pups originating from WT embryos. However, the latter difference was not observed at later time points, nor in the other artificial activating groups. All offspring mated successfully with fertile controls. LIMITATIONS, REASONS FOR CAUTION...... No gross differences were found between strontium chloride, electrical pulses or ionomycin with respect to the pre- and post-implantation development in the wobbler mouse. WHAT IS KNOWN ALREADY Fertilization failure following intra-cytoplasmic sperm injection (ICSI) occurs in 1–3% of the ICSI cycles...

  5. Outpatient Treatment of Lumbar Disc Sciatica

    OpenAIRE

    Swezey, Robert L.; Crittenden, James O.; Swezey, Annette M.

    1986-01-01

    Of 47 patients with lumbar disc disease and sciatic radiculopathy (L-5 or S-1), 39 were successfully managed at home and as outpatients in an ambulatory care facility designed for the treatment of arthritis and back pain. When these patients were evaluated one to three years following discharge, they maintained their maximum level of activity and functional improvement noted at discharge. The average total cost per patient including physician's fees, x-rays, laboratory and therapy was approxi...

  6. Antimicrobial activity of Croton cajucara Benth linalool-rich essential oil on artificial biofilms and planktonic microorganisms.

    Science.gov (United States)

    Alviano, W S; Mendonça-Filho, R R; Alviano, D S; Bizzo, H R; Souto-Padrón, T; Rodrigues, M L; Bolognese, A M; Alviano, C S; Souza, M M G

    2005-04-01

    We have previously demonstrated that a linalool-rich essential oil from Croton cajucara Benth presents leishmanicidal activity. In the present study, we demonstrate that this essential oil inhibits the growth of reference samples of Candida albicans, Lactobacillus casei, Staphylococcus aureus, Streptococcus sobrinus, Porphyromonas gingivalis and Streptococcus mutans cell suspensions, all of them associated with oral cavity disease. The purified linalool fraction was only inhibitory for C. albicans. Microbes of saliva specimens from human individuals with fixed orthodontic appliances, as well as the reference strains, were used to construct an artificial biofilm which was exposed to linalool or to the essential oil. As in microbial suspensions, the essential oil was toxic for all the microorganisms, while the purified linalool fraction mainly inhibited the growth of C. albicans. The compounds of the essential oil were separated by thin layer chromatography and exposed to the above-cited microorganisms. In this analysis, the proliferation of the bacterial cells was inhibited by still uncharacterized molecules, and linalool was confirmed as the antifungal component of the essential oil. The effects of linalool on the cell biology of C. albicans were evaluated by electron microscopy, which showed that linalool induced a reduction in cell size and abnormal germination. Neither the crude essential oil nor the purified linalool fraction is toxic to mammalian cells, which suggests that the essential oil or its purified components may be useful to control the microbial population in patients with fixed orthodontic appliances. PMID:15720570

  7. Prediction and Simulation the Breakthrough of Residual Chlorine Removal by Granular Activated Carbon Adsorbent Using Artificial Neural Networks

    Directory of Open Access Journals (Sweden)

    Rusul Naseer

    2012-07-01

    Full Text Available This study has included two parts. The first part has dealt with carbon production whereas the date Palm was used to produce Granular Activated Carbon (GAC with specific physical characteristics. The new produced of GAC is used to adsorbate the Residual chlorine from water by deep bed filter column. In the second part, the experimental results of the breakthrough of residual chlorine curves is predicted and simulated using artificial neural network with back propagation algorithm whereas the optimum number of neuron was investigated based on RMSE. The removal of residual chlorine has been used as target function in ANN while the other properties of adsorption process such as operation conditions, chlorine concentration in raw water and GAC characteristics has been used as input parameters. The results showed that ANN with back propagation algorithm is a good tool that can be used to predict the best operating parameter for designing GAC layer in multimedia filter whereas 35 neuron gave the best fitting with experimental data. In addition to that, the simulation result was showed that the predictions of breakthrough curve model has been coincided well with the measured values which explained that the depth 25 cm with grain size 1.5 mm of GAC filter bed will be give the optimum removal of residual chlorine from chlorinated water.

  8. Determination of Active Components in a Natural Herb with Near Infrared Spectroscopy Based on Artificial Neural Networks

    Institute of Scientific and Technical Information of China (English)

    LIU Xue-song; QU Hai-bin; CHENG Yi-yu

    2005-01-01

    The non-linear relationships between the contents of ginsenoside Rg1, Rb1, Rd and Panax notoginseng saponins(PNS) in Panax notoginseng root herb and the near infrared(NIR) diffuse reflectance spectra of the herb were established by means of artificial neural networks(ANNs). Four three-layered perception feed-forward networks were trained with an error back-propagation algorithm. The significant principal components of the NIR spectral data matrix were utilized as the input of the networks. The networks architecture and parameters were selected so as to offer less prediction errors. Relative prediction errors for Rg1, Rb1, Rd and PNS obtained with the optimum ANN models were 8.99%, 6.54%, 8.29%, and 5.17%, respectively, which were superior to those obtained with PLSR methods. It is verified that ANN is a suitable approach to model this complex non-linearity. The developed method is fast, non-destructive and accurate and it provides a new efficient approach for determining the active components in the complex system of natural herbs.

  9. Assessment of in vitro Antacid Activity of Different Root Extracts of Tephrosia purpurea (L) Pers by Modified Artificial Stomach Model

    Institute of Scientific and Technical Information of China (English)

    Sandhya S; Venkata Ramana K; Vinod K R; Chaitanya Rsnakk

    2012-01-01

    Objective: The purpose of the present investigation is to rule out the antacid activity of Tephrosiapurpurea root by in vitro method using a self fabricated and modified artificial stomach model. The reason for selecting in vitro method was to minimize the usage of experimental animals. Method:In this work we have used air bubbles from an aerator to mimic the peristaltic movements of stomach. Sodium bicarbonate and water were used as reference and control respectively. The parameters evaluated were neutralizing effect, duration of neutralization effect and capacity and effect of temperature on pH. We evaluated the potency of the plant by extracting with three solvents in increasing order of polarity. Results: The neutralization effect, duration of neutralization effect and capacity were found to be higher for methanol root extract than sodium bicarbonate, whereas ethyl acetate and chloroform extract produced moderately good response but less when compared to standard drug but higher than water. Conclusion: Hence this plant can be an effective alternative for sodium bicarbonate which is reported to have side effects like edema n the feet, alteration in systemic pH, belching etc.

  10. Synthesis and characterization of Gold and Silver nano-particles using different leaf extracts namely Catharanthus roseus, Datura metel and Azadirachta indica and Estimation of antimicrobial activity of silver nano-particles using disc diffusion method

    Directory of Open Access Journals (Sweden)

    Sarbjeet Singh Gujral

    2014-12-01

    Full Text Available Objective: synthesis of gold and silver nano-particles using leaf extracts of Catharanthus roseus, Datura metel and Azadirachta indica and Estimation of antimicrobial activity of silver nano-particles using disc diffusion method. Method: Green approach has been utilized for the synthesis of gold and silver nano-particles. Different aqueous plant extracts has been prepared which was then utilized for the biosynthesis of gold and silver nano-particles. Estimation for the synthesis of nano-particles were done using UV-Visible spectroscopy and Fourier- Transform infrared spectroscopy. Antimicrobial activity of silver nano-particles prepared using aqueous neem extract was investigated using disc diffusion method. Result: UV- Vis spectroscopy of prepared nano-particles was done which gave a peak at about 550 nm for gold nano-particles and around 430 nm for silver nano-particles. FTIR of collected nano-particles gave an idea about the type of bio-molecules which helped in the reduction of auric and silver salts into corresponding nano-particles. Anti-microbial activity of silver nano-particles showed that the nano-particles have better anti-microbial activity than 2% silver nitrate solution (kept as standard when experiments were performed under similar conditions. Conclusion: Gold and silver nano-particles were successfully synthesized using greener approach and anti-microbial activity of silver nano-particles prepared using aqueous neem extract was estimated against 2% AgNO3 solution. Nano-particles gave better anti-microbial activity than Silver nitrate solution.

  11. Discs in misaligned binary systems

    Science.gov (United States)

    Rawiraswattana, Krisada; Hubber, David A.; Goodwin, Simon P.

    2016-08-01

    We perform SPH simulations to study precession and changes in alignment between the circumprimary disc and the binary orbit in misaligned binary systems. We find that the precession process can be described by the rigid-disc approximation, where the disc is considered as a rigid body interacting with the binary companion only gravitationally. Precession also causes change in alignment between the rotational axis of the disc and the spin axis of the primary star. This type of alignment is of great important for explaining the origin of spin-orbit misaligned planetary systems. However, we find that the rigid-disc approximation fails to describe changes in alignment between the disc and the binary orbit. This is because the alignment process is a consequence of interactions that involve the fluidity of the disc, such as the tidal interaction and the encounter interaction. Furthermore, simulation results show that there are not only alignment processes, which bring the components towards alignment, but also anti-alignment processes, which tend to misalign the components. The alignment process dominates in systems with misalignment angle near 90°, while the anti-alignment process dominates in systems with the misalignment angle near 0° or 180°. This means that highly misaligned systems will become more aligned but slightly misaligned systems will become more misaligned.

  12. Amyloid-β(1-42) protofibrils formed in modified artificial cerebrospinal fluid bind and activate microglia.

    Science.gov (United States)

    Paranjape, Geeta S; Terrill, Shana E; Gouwens, Lisa K; Ruck, Benjamin M; Nichols, Michael R

    2013-03-01

    Soluble aggregated forms of amyloid-β protein (Aβ) have garnered significant attention recently for their role in Alzheimer's disease (AD). Protofibrils are a subset of these soluble species and are considered intermediates in the aggregation pathway to mature Aβ fibrils. Biological studies have demonstrated that protofibrils exhibit both toxic and inflammatory activities. It is important in these in vitro studies to prepare protofibrils using solution conditions that are appropriate for cellular studies as well as conducive to biophysical characterization of protofibrils. Here we describe the preparation and characterization of Aβ(1-42) protofibrils in modified artificial cerebrospinal fluid (aCSF) and demonstrate their prominent binding and activation of microglial cells. A simple phosphate/bicarbonate buffer system was prepared that maintained the ionic strength and cell compatibility of F-12 medium but did not contain numerous supplements that interfere with spectroscopic analyses of Aβ protofibrils. Reconstitution of Aβ(1-42) in aCSF and isolation with size exclusion chromatography (SEC) revealed curvilinear β-sheet protofibrils concentration determination by BCA assay, which was not possible in F-12 medium, was more accurately measured in aCSF. Protofibrils formed and isolated in aCSF, but not monomers, markedly stimulated TNFα production in BV-2 and primary microglia and bound in significant amounts to microglial membranes. This report demonstrates the suitability of a modified aCSF system for preparing SEC-isolated Aβ(1-42) protofibrils and underscores the unique ability of protofibrils to functionally interact with microglia. PMID:23242692

  13. Artificial radioactivity in the lower Rhone river. Consequences of floods on activity levels and flow toward the mediterranean

    International Nuclear Information System (INIS)

    Despite analytical strategies that today measure ultra-trace levels (i.e., -5 Bq.L-1) of artificial radionuclides, gamma spectrometry of Rhone River samples taken downstream from the nuclear installations located along the Rhone valley regularly detects only 137Cs, 60Co and 241Am. Since dismantlement of the Marcoule-COGEMA reprocessing plant began in 1997, lists of radionuclides in its effluent include 51Cr, 54Mn, 63Ni, 110mAg and 65Zn, released however at levels 10 to 1,000-fold lower than those of 137Cs or 60Co. Today Marcoule effluent is no longer the principal source of 137Cs in the Rhone River basin, as it was in the 1990's. Significant quantities of 137Cs now come from the Rhone watershed itself, from the drainage of soils exposed to atmospheric fallout from the past nuclear tests and from the accident at Chernobyl, and second, from remobilization of previously formed sediment. Our recent research shows that flood events may generate an increase of more than two orders of magnitude in 137Cs activity in downstream Rhone water, because of the input of contaminated particles from both watershed erosion and sediment remobilization. Flood events also generate the flow of high levels of particulate and associated contaminants towards the Mediterranean Sea. Of the 173±22 GBq of 137Cs transferred from the Rhone to the Mediterranean from August 2002 through August 2003, 111±9 GBq went during two floods in September and November 2002: 60% of the annual transfer took place in only 15 days and included almost ten times as much 137Cs activity as is released annually by the reprocessing plant today. The contribution to these flows of re-mobilized Rhone basin sediment inventories contaminated over the past 40 years is under study today. (authors)

  14. Peripheral Disc Margin Shape and Internal Disc Derangement: Imaging Correlation in Significantly Painful Discs Identified at Provocation Lumbar Discography

    OpenAIRE

    Bartynski, W.S.; Rothfus, W.E.

    2012-01-01

    Annular margin shape is used to characterize lumbar disc abnormality on CT/MR imaging studies. Abnormal discs also have internal derangement including annular degeneration and radial defects. The purpose of this study was to evaluate potential correlation between disc-margin shape and annular internal derangement on post-discogram CT in significantly painful discs encountered at provocation lumbar discography (PLD).

  15. Are galaxy discs optically thick?

    International Nuclear Information System (INIS)

    We re-examine the classical optical evidence for the low optical depths traditionally assigned to spiral discs and argue that it is highly model-dependent and unconvincing. In particular, layered models with a physically thin but optically thick dust layer behave like optically thin discs. The opposite hypotheses, that such discs are optically thick is then examined in the light of modern evidence. We find it to be consistent with the near-infrared and IRAS observations, with the surface brightnesses, with the HI and CO column densities and with the Hα measurements. (author)

  16. High Level Lomber Disc Hernias

    OpenAIRE

    Ateş, Özkan; Tarım, Özcan; Koçak, Ayhan; Önal, S. Çağatay; Çaylı, Süleyman R.; Şahinbeyoğlu, Baran; Tektaş, Şevket

    2002-01-01

    Aim: The scope of this study is to investigate the correlation between the clinical and radiological findings of high level lomber disc hernia (L1-2, L2-3, L3-4) and surgical outcome. Material and Method: 23 high level lomber disc hernia out of 262 lomber disc cases operated between January1996 and November 2001 at the department of Neurosurgery , Faculty of Medicine, İnönü Üniversity (Malatya Turkey) were retrospectively reviewed. Results: 39.1% of the cases were male and...

  17. Artificial Reefs and Ocean Dumping.

    Science.gov (United States)

    Glueck, Richard D.

    1983-01-01

    Activities and instructional strategies for two multigrade lessons are provided. Activity objectives include describing an artificial reef (such as a sunken ocean liner) as an ecosystem, knowing animal types in the ecosystem, and describing a food web. (JN)

  18. Artificial noses.

    Science.gov (United States)

    Stitzel, Shannon E; Aernecke, Matthew J; Walt, David R

    2011-08-15

    The mammalian olfactory system is able to detect many more odorants than the number of receptors it has by utilizing cross-reactive odorant receptors that generate unique response patterns for each odorant. Mimicking the mammalian system, artificial noses combine cross-reactive sensor arrays with pattern recognition algorithms to create robust odor-discrimination systems. The first artificial nose reported in 1982 utilized a tin-oxide sensor array. Since then, however, a wide range of sensor technologies have been developed and commercialized. This review highlights the most commonly employed sensor types in artificial noses: electrical, gravimetric, and optical sensors. The applications of nose systems are also reviewed, covering areas such as food and beverage quality control, chemical warfare agent detection, and medical diagnostics. A brief discussion of future trends for the technology is also provided. PMID:21417721

  19. Total Disc Arthroplasty for Treating Lumbar Degenerative Disc Disease

    OpenAIRE

    Mostofi, Keyvan

    2015-01-01

    Study Design Lumber disc arthroplasty is a technological advancement that has occurred in the last decade to treat lumbar degenerative disk diseases. Purpose The aim of this retrospective study was to establish the impact and outcomes of managing patients with lumbar degenerative disk disease who have been treated with lumbar total disc arthroplasty (TDA). Overview of Literature Several studies have shown promising results following this surgery. Methods We reviewed the files of 104 patients ...

  20. On the convective overstability in protoplanetary discs

    CERN Document Server

    Latter, Henrik

    2015-01-01

    This paper explores the driving of low-level hydrodynamical activity in protoplanetary-disc dead zones. A small adverse radial entropy gradient, ordinarily stabilised by rotation, excites oscillatory convection (`convective overstability') when thermal diffusion, or cooling, is neither too strong nor too weak. I revisit the linear theory of the instability, discuss its prevalence in protoplanetary discs, and show that unstable modes are exact nonlinear solutions in the local Boussinesq limit. Overstable modes cannot grow indefinitely, however, as they are subject to a secondary parametric instability that limits their amplitudes to relatively low levels. If parasites set the saturation level of the ensuing turbulence then the convective overstability is probably too weak to drive significant angular momentum transport or to generate vortices. But I also discuss an alternative, and far more vigorous, saturation route that generates radial `layers' or `zonal flows' (witnessed also in semiconvection). Numerical ...

  1. Intervertebral disc (IVD): Structure, degeneration, repair and regeneration

    Energy Technology Data Exchange (ETDEWEB)

    Whatley, Benjamin R.; Wen Xuejun, E-mail: xjwen@clemson.edu

    2012-02-01

    Low back pain affects a large portion of the population, resulting in high care costs for therapy and treatment. One primary cause of low back pain is the degeneration of the intervertebral disc (IVD) resulting in the compression of the spinal nerves and adjacent vertebrae. Exact causes of degeneration are unknown, but it is thought that natural aging, and both biological and genetic factors may play a significant role in the degenerative process. Conventional methods to alleviate low back pain include spinal fusion and artificial disc replacement. Traditional treatments through spinal fusion may eliminate pain yet do not restore disc function and lead to further degeneration of adjacent levels by altering disc biomechanics and natural kinematics. Recently, artificial IVD replacements have started to gain interest, with two IVD implants currently approved in the United States. Although these implants facilitate the preservation of motions and disc space height, they are unable to sustain compressive forces due to their lack of elasticity. In addition, the implants may produce wear debris that can cause osteolysis and other deleterious effects. As an alternative to these conventional approaches, tissue engineered IVD constructs offer the advantage of biointegration while preserving the essential attributes of natural motion and disc space restoration. There is a great need for the development of tissue engineered scaffolds that simulate the natural 3D morphology and microenvironment of the targeted tissue. Scaffolds should facilitate biological transport to satisfy nutrition and waste removal requirements within the IVD. The discrete tissue architectures of the nucleus pulposus (NP) and annulus fibrosus (AF) have posed great challenges to IVD tissue engineering. Current attempts have not been able to satisfy the biological functions and/or mechanical properties of native tissue. Therefore, these current scaffolds are far from satisfactory. This review highlights the

  2. Intervertebral disc (IVD): Structure, degeneration, repair and regeneration

    International Nuclear Information System (INIS)

    Low back pain affects a large portion of the population, resulting in high care costs for therapy and treatment. One primary cause of low back pain is the degeneration of the intervertebral disc (IVD) resulting in the compression of the spinal nerves and adjacent vertebrae. Exact causes of degeneration are unknown, but it is thought that natural aging, and both biological and genetic factors may play a significant role in the degenerative process. Conventional methods to alleviate low back pain include spinal fusion and artificial disc replacement. Traditional treatments through spinal fusion may eliminate pain yet do not restore disc function and lead to further degeneration of adjacent levels by altering disc biomechanics and natural kinematics. Recently, artificial IVD replacements have started to gain interest, with two IVD implants currently approved in the United States. Although these implants facilitate the preservation of motions and disc space height, they are unable to sustain compressive forces due to their lack of elasticity. In addition, the implants may produce wear debris that can cause osteolysis and other deleterious effects. As an alternative to these conventional approaches, tissue engineered IVD constructs offer the advantage of biointegration while preserving the essential attributes of natural motion and disc space restoration. There is a great need for the development of tissue engineered scaffolds that simulate the natural 3D morphology and microenvironment of the targeted tissue. Scaffolds should facilitate biological transport to satisfy nutrition and waste removal requirements within the IVD. The discrete tissue architectures of the nucleus pulposus (NP) and annulus fibrosus (AF) have posed great challenges to IVD tissue engineering. Current attempts have not been able to satisfy the biological functions and/or mechanical properties of native tissue. Therefore, these current scaffolds are far from satisfactory. This review highlights the

  3. Artificial intelligence

    International Nuclear Information System (INIS)

    A vivid example of the growing need for frontier physics experiments to make use of frontier technology is in the field of artificial intelligence and related themes. This was reflected in the second international workshop on 'Software Engineering, Artificial Intelligence and Expert Systems in High Energy and Nuclear Physics' which took place from 13-18 January at France Telecom's Agelonde site at La Londe des Maures, Provence. It was the second in a series, the first having been held at Lyon in 1990

  4. Artificial Intelligence

    CERN Document Server

    Warwick, Kevin

    2011-01-01

    if AI is outside your field, or you know something of the subject and would like to know more then Artificial Intelligence: The Basics is a brilliant primer.' - Nick Smith, Engineering and Technology Magazine November 2011 Artificial Intelligence: The Basics is a concise and cutting-edge introduction to the fast moving world of AI. The author Kevin Warwick, a pioneer in the field, examines issues of what it means to be man or machine and looks at advances in robotics which have blurred the boundaries. Topics covered include: how intelligence can be defined whether machines can 'think' sensory

  5. Debris disc formation induced by planetary growth

    CERN Document Server

    Kobayashi, Hiroshi

    2014-01-01

    Several hundred stars older than 10 million years have been observed to have infrared excesses. These observations are explained by dust grains formed by the collisional fragmentation of hidden planetesimals. Such dusty planetesimal discs are known as debris discs. In a dynamically cold planetesimal disc, collisional coagulation of planetesimals produces planetary embryos which then stir the surrounding leftover planetesimals. Thus, the collisional fragmentation of planetesimals that results from planet formation forms a debris disc. We aim to determine the properties of the underlying planetesimals in debris discs by numerically modelling the coagulation and fragmentation of planetesimal populations. The brightness and temporal evolution of debris discs depend on the radial distribution of planetesimal discs, the location of their inner and outer edges, their total mass, and the size of planetesimals in the disc. We find that a radially narrow planetesimal disc is most likely to result in a debris disc that ...

  6. Vortex migration in protoplanetary discs

    Directory of Open Access Journals (Sweden)

    Papaloizou John C. B.

    2013-04-01

    Full Text Available Vortices embedded in protoplanetary discs can act as obstacles to the unperturbed disc flow. The resulting velocity perturbations propagate away from the vortex in the form of density waves that transport angular momentum. Any asymmetry between the inner and the outer density wave means that the region around the vortex has to change its angular momentum. We find that this leads to orbital migration of the vortex. Asymmetric waves always arise except in the case of a disc with constant pressure, for isothermal as well as non-isothermal discs. Depending on the size and strength of the vortex, the resulting migration time scales can be as short as a few thousand orbits.

  7. Cervical Disc Disease: Biomechanical Aspects

    OpenAIRE

    Kolstad, Frode

    2011-01-01

    Degenerative disc disease in the cervical spine may cause significant pain and disability. Patients present themselves with neck pain, radiculopathy, and/or myelopathy. When the symptoms do not improve with conservative treatment, surgical treatment is considered. The goal of surgical treatment is to decompress nervous structures and to restore the normal anatomical conditions of disc height, alignment, and stability.The present thesis concerns four studies involving the treatment of cervical...

  8. Corticosteroids in Lumbar Disc Surgery

    OpenAIRE

    Lundin, Anders

    2005-01-01

    In a prospective randomised double-blind study eighty patients with MRI verified lumbar disc herniation and corresponding clinical findings underwent microscopic disc removal. The patients were peroperatively given systemic and local corticosteroids or placebo, and followed for 2 years. The hospital stay and time to return to full-time work was significantly shorter in the treatment group. Pain measured as worst pain during the last week was also lower in the corticosteroid group. The results...

  9. Artificial sweeteners

    DEFF Research Database (Denmark)

    Raben, Anne Birgitte; Richelsen, Bjørn

    2012-01-01

    Artificial sweeteners can be a helpful tool to reduce energy intake and body weight and thereby risk for diabetes and cardiovascular diseases (CVD). Considering the prevailing diabesity (obesity and diabetes) epidemic, this can, therefore, be an important alternative to natural, calorie-containin...

  10. Artificial photosynthesis

    OpenAIRE

    Andrew C. Benniston; Anthony Harriman

    2008-01-01

    We raise here a series of critical issues regarding artificial photosynthesis with the intention of increasing awareness about what needs to be done to bring about a working prototype. Factors under consideration include energy and electron transfers, coupled redox reactions, repair mechanisms, and integrated photosystems.

  11. Lumbar disc cyst with contralateral radiculopathy

    OpenAIRE

    Kishore Tourani; Belman Murali; Akshay Sahoo; Dandu Ravi Varma; Narayan Prasad

    2012-01-01

    Disc cysts are uncommon intraspinal cystic lesions located in the ventrolateral epidural space. They communicate with the nucleus pulposus of the intervertebral disc and cause symptoms by radicular compression. We report a unique case of lumbar disc cyst that was associated with disc herniation and contralateral radiculopathy. A 22 year old male presented with one month history of back-ache radiating to the left leg. Magnetic Resonance Imaging (MRI) showed L3-L4 disc herniation with annular t...

  12. Artificial organisms that sleep.

    OpenAIRE

    Mirolli, Marco; Parisi, Domenico

    2003-01-01

    Abstract Populations of artificial organisms live in an environment in which light is cyclically present (day) or absent (night). Since being active during night is non-adaptive (activity consumes energy which is not compensated by the food found at night) the organisms evolve a sleep/wake behavioral pattern of being active during daytime and sleeping during nighttime. When the population moves to a different environment that contains "caves", they have to get out of a cave although the dark ...

  13. Counter-Rotating Accretion Discs

    CERN Document Server

    Dyda, Sergei; Ustyugova, Galina V; Romanova, Marina M; Koldoba, Alexander V

    2014-01-01

    Counter-rotating discs can arise from the accretion of a counter-rotating gas cloud onto the surface of an existing co-rotating disc or from the counter-rotating gas moving radially inward to the outer edge of an existing disc. At the interface, the two components mix to produce gas or plasma with zero net angular momentum which tends to free-fall towards the disc center. We discuss high-resolution axisymmetric hydrodynamic simulations of a viscous counter-rotating disc for cases where the two components are vertically separated and radially separated. The viscosity is described by an isotropic $\\alpha-$viscosity including all terms in the viscous stress tensor. For the vertically separated components a shear layer forms between them. The middle of this layer free-falls to the disk center. The accretion rates are increased by factors $\\sim 10^2-10^4$ over that of a conventional disc rotating in one direction with the same viscosity. The vertical width of the shear layer and the accretion rate are strongly dep...

  14. Production of artificial radioelements

    International Nuclear Information System (INIS)

    The techniques used in the production of artificial radioelements are described, with special emphasis on the following points: - nuclear reactions and use of reactors; - chemical separation methods and methods for enriching the activity of preparations; - protection of personnel and handling methods. (author)

  15. Testing hydrodynamics schemes in galaxy disc simulations

    Science.gov (United States)

    Few, C. G.; Dobbs, C.; Pettitt, A.; Konstandin, L.

    2016-08-01

    We examine how three fundamentally different numerical hydrodynamics codes follow the evolution of an isothermal galactic disc with an external spiral potential. We compare an adaptive mesh refinement code (RAMSES), a smoothed particle hydrodynamics code (SPHNG), and a volume-discretized mesh-less code (GIZMO). Using standard refinement criteria, we find that RAMSES produces a disc that is less vertically concentrated and does not reach such high densities as the SPHNG or GIZMO runs. The gas surface density in the spiral arms increases at a lower rate for the RAMSES simulations compared to the other codes. There is also a greater degree of substructure in the SPHNG and GIZMO runs and secondary spiral arms are more pronounced. By resolving the Jeans length with a greater number of grid cells, we achieve more similar results to the Lagrangian codes used in this study. Other alterations to the refinement scheme (adding extra levels of refinement and refining based on local density gradients) are less successful in reducing the disparity between RAMSES and SPHNG/GIZMO. Although more similar, SPHNG displays different density distributions and vertical mass profiles to all modes of GIZMO (including the smoothed particle hydrodynamics version). This suggests differences also arise which are not intrinsic to the particular method but rather due to its implementation. The discrepancies between codes (in particular, the densities reached in the spiral arms) could potentially result in differences in the locations and time-scales for gravitational collapse, and therefore impact star formation activity in more complex galaxy disc simulations.

  16. Inhomogeneous accretion discs and the soft states of black hole X-ray binaries

    OpenAIRE

    Dexter, Jason; Quataert, Eliot

    2012-01-01

    Observations of black hole binaries (BHBs) have established a rich phenomenology of X-ray states. The soft states range from the low variability, accretion disc dominated thermal state (TD) to the higher variability, non-thermal steep power law state (SPL). The disc component in all states is typically modeled with standard thin disc accretion theory. However, this theory is inconsistent with optical/UV spectral, variability, and gravitational microlensing observations of active galactic nucl...

  17. Anterior Lumbar Intervertebrai Fusion with Artificial Bone in Place of Autologous Bone

    Institute of Scientific and Technical Information of China (English)

    徐卫国; 陈安民; 冯旭; 印卫锋

    2003-01-01

    The feasibility of anterior lumbar intervertebral fusion with artificial bone in place of au-togenous bone was investigated. Porous hydroxyapatite(HA)/ZrO2 ceramics loading bone morpho-genetic protein (BMP) were implanted after removal of lumbar vertebral disc in rabbits. The adja-cent intervertebral discs were also removed by the same way and autogenous illic bone was implan-ted. SEM observation and biomechanical test were carried out. Compound bone had a bit lower os-teoinductive activity than autogenous bone by SEM(Osteoindutive activity of artificial bone in 12weeks was the same as that of autogenous bone in 9 weeks). Biomechanical test revealed that com-pound bone had lower anti-pull strength than autogenous bone (P<0. 001), but there was no sig-nificant difference in anti-pull strength between compound bone at 12th week and autogenous boneat 9th week (P>0.05). It was concluded that compound bone could be applied for anterior spinalfusion, especially for those patients who can't use autogenous bone.

  18. Inhomogeneous accretion discs and the soft states of black hole X-ray binaries

    Science.gov (United States)

    Dexter, Jason; Quataert, Eliot

    2012-10-01

    Observations of black hole binaries (BHBs) have established a rich phenomenology of X-ray states. The soft states range from the low variability, accretion disc dominated thermal (TD) state to the higher variability, non-thermal steep power law (SPL) state. The disc component in all states is typically modelled with standard thin disc accretion theory. However, this theory is inconsistent with optical/UV spectral, variability and gravitational microlensing observations of active galactic nuclei (AGNs), the supermassive analogues of BHBs. An inhomogeneous disc (ID) model with large (≃0.4 dex) temperature fluctuations in each radial annulus can qualitatively explain all of these AGN observations. The inhomogeneity may be a consequence of instabilities in radiation-dominated discs, and therefore may be present in BHBs as well. We show that ID models can explain many features of the TD and SPL states of BHBs. The observed relationships between spectral hardness, disc fraction and rms variability amplitude in BHBs are reproduced with temperature fluctuations similar to those inferred in AGNs, suggesting a unified picture of luminous accretion discs across orders of magnitude in black hole mass. This picture can be tested with spectral fitting of ID models, X-ray polarization observations and radiation magnetohydrodynamic simulations. If BHB accretion discs are indeed inhomogeneous, only the most disc-dominated states (disc fraction ≳0.95) can be used to robustly infer black hole spin using current continuum fitting methods.

  19. Artificial Intelligence.

    Science.gov (United States)

    Lawrence, David R; Palacios-González, César; Harris, John

    2016-04-01

    It seems natural to think that the same prudential and ethical reasons for mutual respect and tolerance that one has vis-à-vis other human persons would hold toward newly encountered paradigmatic but nonhuman biological persons. One also tends to think that they would have similar reasons for treating we humans as creatures that count morally in our own right. This line of thought transcends biological boundaries-namely, with regard to artificially (super)intelligent persons-but is this a safe assumption? The issue concerns ultimate moral significance: the significance possessed by human persons, persons from other planets, and hypothetical nonorganic persons in the form of artificial intelligence (AI). This article investigates why our possible relations to AI persons could be more complicated than they first might appear, given that they might possess a radically different nature to us, to the point that civilized or peaceful coexistence in a determinate geographical space could be impossible to achieve. PMID:26957450

  20. Effect of optic disc size or age on evaluation of optic disc variables

    OpenAIRE

    Kee, C.; Koo, H.; Ji, Y; S. Kim

    1997-01-01

    AIMS/BACKGROUND—It has been reported that the number of optic nerve fibres decrease with age, and the cup/disc (C/D) ratio increases as the optic disc size increases. Consequently, the normal value of the optic disc variables measured by an optic disc analyser may change according to the optic disc size or age. The effect of individual variations in optic disc size or age on interpretation of optic disc variables was investigated.
METHODS—Topographic optic disc variables of 104 normal Asian a...

  1. Artificial intelligence

    OpenAIRE

    Duda, Antonín

    2009-01-01

    Abstract : Issue of this work is to acquaint the reader with the history of artificial inteligence, esspecialy branch of chess computing. Main attention is given to progress from fifties to the present. The work also deals with fighting chess programs against each other, and against human opponents. The greatest attention is focused on 1997 and duel Garry Kasparov against chess program Deep Blue. The work is divided into chapters according to chronological order.

  2. Quantitative structure–activity relationship study of P2X7 receptor inhibitors using combination of principal component analysis and artificial intelligence methods

    Science.gov (United States)

    Ahmadi, Mehdi; Shahlaei, Mohsen

    2015-01-01

    P2X7 antagonist activity for a set of 49 molecules of the P2X7 receptor antagonists, derivatives of purine, was modeled with the aid of chemometric and artificial intelligence techniques. The activity of these compounds was estimated by means of combination of principal component analysis (PCA), as a well-known data reduction method, genetic algorithm (GA), as a variable selection technique, and artificial neural network (ANN), as a non-linear modeling method. First, a linear regression, combined with PCA, (principal component regression) was operated to model the structure–activity relationships, and afterwards a combination of PCA and ANN algorithm was employed to accurately predict the biological activity of the P2X7 antagonist. PCA preserves as much of the information as possible contained in the original data set. Seven most important PC's to the studied activity were selected as the inputs of ANN box by an efficient variable selection method, GA. The best computational neural network model was a fully-connected, feed-forward model with 7−7−1 architecture. The developed ANN model was fully evaluated by different validation techniques, including internal and external validation, and chemical applicability domain. All validations showed that the constructed quantitative structure–activity relationship model suggested is robust and satisfactory. PMID:26600858

  3. Quantitative structure-activity relationship study of P2X7 receptor inhibitors using combination of principal component analysis and artificial intelligence methods.

    Science.gov (United States)

    Ahmadi, Mehdi; Shahlaei, Mohsen

    2015-01-01

    P2X7 antagonist activity for a set of 49 molecules of the P2X7 receptor antagonists, derivatives of purine, was modeled with the aid of chemometric and artificial intelligence techniques. The activity of these compounds was estimated by means of combination of principal component analysis (PCA), as a well-known data reduction method, genetic algorithm (GA), as a variable selection technique, and artificial neural network (ANN), as a non-linear modeling method. First, a linear regression, combined with PCA, (principal component regression) was operated to model the structure-activity relationships, and afterwards a combination of PCA and ANN algorithm was employed to accurately predict the biological activity of the P2X7 antagonist. PCA preserves as much of the information as possible contained in the original data set. Seven most important PC's to the studied activity were selected as the inputs of ANN box by an efficient variable selection method, GA. The best computational neural network model was a fully-connected, feed-forward model with 7-7-1 architecture. The developed ANN model was fully evaluated by different validation techniques, including internal and external validation, and chemical applicability domain. All validations showed that the constructed quantitative structure-activity relationship model suggested is robust and satisfactory. PMID:26600858

  4. Neurexin-Neuroligin Synaptic Complex Regulates Schizophrenia-Related DISC1/Kal-7/Rac1 "Signalosome"

    DEFF Research Database (Denmark)

    Owczarek, Sylwia; Bang, Marie Louise; Berezin, Vladimir

    2015-01-01

    -attached intracellular domain in an activity-dependent manner, generating the soluble ectodomain of NX or NL. Expression of the NX1 and NX3 genes in the brain appears to be regulated by a schizophrenia-related protein, DISC1. Here, we show that soluble ecto-NX1β can regulate the expression of DISC1 and induce signaling...... downstream of DISC1. We also show that NL1 binds to a well-characterized DISC1 interaction partner, Kal-7, and this interaction can be compromised by DISC1. Our results indicate that the NX/NL synaptic complex is intrinsically involved in the regulation of DISC1 function, thus contributing to a better...

  5. Automatic diagnosis of lumbar disc herniation with shape and appearance features from MRI

    Science.gov (United States)

    Alomari, Raja'S.; Corso, Jason J.; Chaudhary, Vipin; Dhillon, Gurmeet

    2010-03-01

    Intervertebral disc herniation is a major reason for lower back pain (LBP), which is the second most common neurological ailment in the United States. Automation of herniated disc diagnosis reduces the large burden on radiologists who have to diagnose hundreds of cases each day using clinical MRI. We present a method for automatic diagnosis of lumbar disc herniation using appearance and shape features. We jointly use the intensity signal for modeling the appearance of herniated disc and the active shape model for modeling the shape of herniated disc. We utilize a Gibbs distribution for classification of discs using appearance and shape features. We use 33 clinical MRI cases of the lumbar area for training and testing both appearance and shape models. We achieve over 91% accuracy in detection of herniation in a cross-validation experiment with specificity of 91% and sensitivity of 94%.

  6. Inhomogeneous accretion discs and the soft states of black hole X-ray binaries

    CERN Document Server

    Dexter, Jason

    2012-01-01

    Observations of black hole binaries (BHBs) have established a rich phenomenology of X-ray states. The soft states range from the low variability, accretion disc dominated thermal state (TD) to the higher variability, non-thermal steep power law state (SPL). The disc component in all states is typically modeled with standard thin disc accretion theory. However, this theory is inconsistent with optical/UV spectral, variability, and gravitational microlensing observations of active galactic nuclei (AGNs), the supermassive analogs of BHBs. An inhomogeneous disc (ID) model with large (~0.4 dex) temperature fluctuations in each radial annulus can qualitatively explain all of these AGN observations. The inhomogeneity may be a consequence of instabilities in radiation dominated discs, and therefore may be present in BHBs as well. We show that ID models can explain many features of the TD and SPL states of BHBs. The observed relationships between spectral hardness, disc fraction, and rms variability amplitude in BHBs ...

  7. Chondrule transport in protoplanetary discs

    Science.gov (United States)

    Goldberg, Aaron Z.; Owen, James E.; Jacquet, Emmanuel

    2015-10-01

    Chondrule formation remains one of the most elusive early Solar system events. Here, we take the novel approach of employing numerical simulations to investigate chondrule origin beyond purely cosmochemical methods. We model the transport of generically produced chondrules and dust in a 1D viscous protoplanetary disc model in order to constrain the chondrule formation events. For a single formation event we are able to match analytical predictions of the memory they retain of each other (complementarity), finding that a large mass accretion rate (≳10-7 M⊙ yr-1) allows for delays on the order of the disc's viscous time-scale between chondrule formation and chondrite accretion. Further, we find older discs to be severely diminished of chondrules, with accretion rates ≲10-9 M⊙ yr-1 for nominal parameters. We then characterize the distribution of chondrule origins in both space and time, as functions of disc parameters and chondrule formation rates, in runs with continuous chondrule formation and both static and evolving discs. Our data suggest that these can account for the observed diversity between distinct chondrite classes, if some diversity in accretion time is allowed for.

  8. Tidally-induced warps in protostellar discs

    OpenAIRE

    Terquem, C.; Papaloizou, J.; Nelson, R.(University of California, Davis, Davis, USA)

    1998-01-01

    We review results on the dynamics of warped gaseous discs. We consider tidal perturbation of a Keplerian disc by a companion star orbiting in a plane inclined to the disc. The perturbation induces the precession of the disc, and thus of any jet it could drive. In some conditions the precession rate is uniform, and as a result the disc settles into a warp mode. The tidal torque also leads to the truncation of the disc, to the evolution of the inclination angle (not necessarily towards alignmen...

  9. Competitive coordination aggregation for V-shaped [Co3] and disc-like [Co7] complexes: synthesis, magnetic properties and catechol oxidase activity.

    Science.gov (United States)

    Singha Mahapatra, Tufan; Basak, Dipmalya; Chand, Santanu; Lengyel, Jeff; Shatruk, Michael; Bertolasi, Valerio; Ray, Debashis

    2016-09-14

    Unique dependence on the nature of metal salt and reaction conditions for coordination assembly reactions of varying architecture and nuclearity have been identified in V-shaped [Co3L4] and planar disc-like [Co7L6] compounds: [CoL2(μ-L)2(μ-OH2)2(CF3CO2)2] (1) and [Co(μ-L)6(μ-OMe)6]Cl2 (2) (HL = 2-{(3-ethoxypropylimino)methyl}-6-methoxyphenol). At room temperature varying reaction conditions, cobalt-ligand ratios and use of different bases allowed unique types of coordination self-assembly. The synthetic marvel lies in the nature of aggregation with respect to the two unrelated cores in 1 and 2. Complex 1 assumes a V-shaped arrangement bound to L(-), water and a trifluoroacetate anion, while 2 grows around a central Co(II) ion surrounded by a {Co} hexagon bound to methoxide and L(-). Magnetic measurements revealed that the intermetallic interactions are antiferromagnetic in nature in the case of complex 1 and ferromagnetic in the case of 2 involving high spin cobalt(ii) ions with stabilization of the high-spin ground state in the latter case. In MeCN solutions complexes 1 and 2 showed catalytic oxidation of 3,5-di-tert-butylcatechol (3,5-DTBCH2) to 3,5-di-tert-butylbenzoquinone (3,5-DTBQ) in air. The kinetic study in MeCN revealed that with respect to the catalytic turnover number (kcat) 2 is more effective than 1 for oxidation of 3,5-DTBCH2. PMID:27510847

  10. An active artificial cornea with the function of inducing new corneal tissue generation in vivo-a new approach to corneal tissue engineering

    International Nuclear Information System (INIS)

    An active artificial cornea which can perform the function of inducing new cornea generation in vivo but does not need culture cells in vitro and which has similar optical and mechanical properties to those of the human cornea was constructed. An animal keratoplasty experiment using the artificial cornea as the implant showed that the animals' corneas could keep smooth surface and clear stroma postoperatively, and that the repopulation of the host's keratocytes, the degradation of the implant and new corneal tissue generation were completed at 5-6 months after surgery. Such an artificial cornea has several advantages over other corneal equivalents constructed in the typical way of tissue engineering: in having similar mechanical and optical properties to those of the human cornea and with no exogenetic cells, it can be used universally in different implantation surgeries without immunoreaction; it is easy to prepare and process into different shapes and sizes on a large scale, and suitable for long-distance transportation and long-term storage. All these characteristics make it a new approach to cornea tissue engineering having potential in many clinical applications

  11. Synthesis of TiO2 nanoparticles in different thermal conditions and modeling its photocatalytic activity with artificial neural network

    Institute of Scientific and Technical Information of China (English)

    Fatemeh Ghanbary; Nasser Modirshahla; Morteza Khosravi; Mohammad Ali Behnajady

    2012-01-01

    Titanium dioxide (TiO2) nanoparticles were prepared by sol gel route.The preparation parameters were optimized in the removal of 4-nitrophenol (4-NP).All catalysts were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM).An artificial neural network model (ANN) was developed to predict the photocatalytic removal of 4-NP in the presence of TiO2 nanoparticles prepared under desired conditions.The comparison between the predicted results by designed ANN model and the experimental data proved that modeling of the removal process of 4-NP using artificial neural network was a precise method to predict the extent of 4-NP removal under different conditions.

  12. Laser engineering of spine discs

    Science.gov (United States)

    Sobol, E.; Zakharkina, O.; Baskov, A.; Shekhter, A.; Borschenko, I.; Guller, A.; Baskov, V.; Omelchenko, A.; Sviridov, A.

    2009-04-01

    The laser engineering of intervertebral discs is one of the branch of medical physics aimed at the development of minimally invasive laser medical techniques based on the effect of the controlled (time- and space-modulated) laser radiation on the structure and the field of mechanical stress of biological tissues. A new method for the laser engineering of the intervertebral discs and the differences of this approach from the existing physical methods of medical treatment are considered. The newly formed tissues of animals and humans are hystologically studied. Possible regeneration processes are discussed. A control system that provides for the treatment efficiency and safety is developed. The new laser medical equipment that is designed for the laser engineering of intervertebral discs is described, and the corresponding results of the clinical application are presented.

  13. Black hole accretion disc impacts

    Science.gov (United States)

    Pihajoki, P.

    2016-04-01

    We present an analytic model for computing the luminosity and spectral evolution of flares caused by a supermassive black hole impacting the accretion disc of another supermassive black hole. Our model includes photon diffusion, emission from optically thin regions and relativistic corrections to the observed spectrum and time-scales. We test the observability of the impact scenario with a simulated population of quasars hosting supermassive black hole binaries. The results indicate that for a moderate binary mass ratio of 0.3, and impact distances of 100 primary Schwarzschild radii, the accretion disc impacts can be expected to equal or exceed the host quasar in brightness at observed wavelength λ = 510 nm up to z = 0.6. We conclude that accretion disc impacts may function as an independent probe for supermassive black hole binaries. We release the code used for computing the model light curves to the community.

  14. Black hole accretion disc impacts

    CERN Document Server

    Pihajoki, Pauli

    2015-01-01

    We present an analytic model for computing the luminosity and spectral evolution of flares caused by a supermassive black hole impacting the accretion disc of another supermassive black hole. Our model includes photon diffusion, emission from optically thin regions and relativistic corrections to the observed spectrum and time-scales. We test the observability of the impact scenario with a simulated population of quasars hosting supermassive black hole binaries. The results indicate that for a moderate binary mass ratio of 0.3, and impact distances of 100 primary Schwarzschild radii, the accretion disc impacts can be expected to equal or exceed the host quasar in brightness at observed wavelength {\\lambda} = 510 nm up to z = 0.6. We conclude that accretion disc impacts may function as an independent probe for supermassive black hole binaries. We release the code used for computing the model light curves to the community.

  15. A strong and stretchable self-healing film with self-activated pressure sensitivity for potential artificial skin applications

    OpenAIRE

    Hou, Chengyi; Huang, Tao; Wang, Hongzhi; Yu, Hao; Zhang, Qinghong; Li, Yaogang

    2013-01-01

    Artificial skin, which mimics the functions of natural skin, will be very important in the future for robots used by humans in daily life. However, combining skin's pressure sensitivity and mechanical self-healing properties in a man-made material remains a challenging task. Here, we show that graphene and polymers can be integrated into a thin film which mimics both the mechanical self-healing and pressure sensitivity behavior of natural skin without any external power supply. Its ultimate s...

  16. Diagnosis of cervical disc disease

    International Nuclear Information System (INIS)

    High resolution CT easily localized lesions including soft tissues of the bone such as disc protrusion and thickening of the yellow ligament. In all cases, myelography demonstrated compression of the nerve roots of the spinal cord which corresponded to CT findings at the level where plain CT revealed a lesion. However, CT metrizamide myelography demonstrated the lesion more clearly than did conventional myelography. CT metrizamide myelography also outlined compression of the nerve roots satisfactorily and demonstrated compressed findings of the spinal cord in the dynamic study. Thus, high resolution CT was useful for screening of cervical disc disease, and CT metrizamide myelography, for identification of lesions of the nerve roots. (Chiba, N.)

  17. Vertebral osteomyelitis without disc involvement

    Energy Technology Data Exchange (ETDEWEB)

    Kamani, I.; Syed, I.; Saifuddin, A. E-mail: asaifuddin@aol.com; Green, R.; MacSweeney, F

    2004-10-01

    Vertebral osteomyelitis is most commonly due to pyogenic or granulomatous infection and typically results in the combined involvement of the intervertebral disc and adjacent vertebral bodies. Non-infective causes include the related conditions of chronic recurrent multifocal osteomyelitis (CRMO) and SAPHO (synovitis, acne, pustulosis, hyperostosis, and osteitis) syndrome. Occasionally, these conditions may present purely within the vertebral body, resulting in various combinations of vertebral marrow oedema and sclerosis, destructive lesions of the vertebral body and pathological vertebral collapse, thus mimicking neoplastic disease. This review illustrates the imaging features of vertebral osteomyelitis without disc involvement, with emphasis on magnetic resonance imaging (MRI) findings.

  18. Design, RNA cleavage and antiviral activity of new artificial ribonucleases derived from mono-, di- and tripeptides connected by linkers of different hydrophobicity.

    Science.gov (United States)

    Tamkovich, Nikolay; Koroleva, Lyudmila; Kovpak, Mikhail; Goncharova, Elena; Silnikov, Vladimir; Vlassov, Valentin; Zenkova, Marina

    2016-03-15

    A novel series of metal-free artificial ribonucleases (aRNases) was designed, synthesized and assessed in terms of ribonuclease activity and ability to inactivate influenza virus WSN/A33/H1N1 in vitro. The compounds were built of two short peptide fragments, which include Lys, Ser, Arg, Glu and imidazole residues in various combinations, connected by linkers of different hydrophobicity (1,12-diaminododecane or 4,9-dioxa-1,12-diaminododecane). These compounds efficiently cleaved different RNA substrates under physiological conditions at rates three to five times higher than that of artificial ribonucleases described earlier and displayed RNase A-like cleavage specificity. aRNases with the hydrophobic 1,12-diaminododecane linker displayed ribonuclease activity 3-40 times higher than aRNases with the 4,9-dioxa-1,12-diaminododecane linker. The assumed mechanism of RNA cleavage was typical for natural ribonucleases, that is, general acid-base catalysis via the formation of acid/base pairs by functional groups of amino acids present in the aRNases; the pH profile of cleavage confirmed this mechanism. The most active aRNases under study exhibited high antiviral activity and entirely inactivated influenza virus A/WSN/33/(H1N1) after a short incubation period of viral suspension under physiological conditions. PMID:26899594

  19. Hydrodynamic instability in eccentric astrophysical discs

    CERN Document Server

    Barker, Adrian J

    2014-01-01

    Eccentric Keplerian discs are believed to be unstable to three-dimensional hydrodynamical instabilities driven by the time-dependence of fluid properties around an orbit. These instabilities could lead to small-scale turbulence, and ultimately modify the global disc properties. We use a local model of an eccentric disc, derived in a companion paper, to compute the nonlinear vertical ("breathing mode") oscillations of the disc. We then analyse their linear stability to locally axisymmetric disturbances for any disc eccentricity and eccentricity gradient using a numerical Floquet method. In the limit of small departures from a circular reference orbit, the instability of an isothermal disc is explained analytically. We also study analytically the small-scale instability of an eccentric neutrally stratified polytropic disc with any polytropic index using a WKB approximation. We find that eccentric discs are generically unstable to the parametric excitation of small-scale inertial waves. The nonlinear evolution o...

  20. Prediction of the correct measured activity of 186Re and 188Re from reactor produced natural rhenium using an artificial neural network

    International Nuclear Information System (INIS)

    To optimize the cost effectiveness of 186Re and 188Re production, which have recently been used as radio pharmaceuticals for therapeutic purposes, we designed an artificial neural network (ANN) to evaluate the activity of combined 186Re + 188Re. One of the production ways is the (n,γ) reaction of natural rhenium which leads to combined 186Re + 188Re. Using the counted activity of 186Re + 188Re mixtures by a well type isotope calibrator, the precise activity of 186Re and 188Re is obtained by the ANN. A back-propagation ANN was trained using 30 activities of mixed 186Re + 188Re. The performance of the ANN was tested by Early-Stopping validation method, and the ANN was optimized with respect to its architecture. The response of the ANN shows significant precision that may be used for medical application of 186Re + 188Re mixtures.

  1. Whispering galleries and the control of artificial atoms

    Science.gov (United States)

    Forrester, Derek Michael; Kusmartsev, Feodor V.

    2016-01-01

    Quantum computation using artificial-atoms, such as novel superconducting circuits, can be sensitively controlled by external electromagnetic fields. These fields and the self-fields attributable to the coupled artificial-atoms influence the amount of quantum correlation in the system. However, control elements that can operate without complete destruction of the entanglement of the quantum-bits are difficult to engineer. Here we investigate the possibility of using closely-spaced-linear arrays of metallic-elliptical discs as whispering gallery waveguides to control artificial-atoms. The discs confine and guide radiation through the array with small notches etched into their sides that act as scatterers. We focus on π-ring artificial-atoms, which can generate their own spontaneous fluxes. We find that the micro-discs of the waveguides can be excited by terahertz frequency fields to exhibit whispering-modes and that a quantum-phase-gate composed of π-rings can be operated under their influence. Furthermore, we gauge the level of entanglement through the concurrence measure and show that under certain magnetic conditions a series of entanglement sudden-deaths and revivals occur between the two qubits. This is important for understanding the stability and life-time of qubit operations using, for example, a phase gate in a hybrid of quantum technologies composed of control elements and artificial-atoms. PMID:27122353

  2. Whispering galleries and the control of artificial atoms.

    Science.gov (United States)

    Forrester, Derek Michael; Kusmartsev, Feodor V

    2016-01-01

    Quantum computation using artificial-atoms, such as novel superconducting circuits, can be sensitively controlled by external electromagnetic fields. These fields and the self-fields attributable to the coupled artificial-atoms influence the amount of quantum correlation in the system. However, control elements that can operate without complete destruction of the entanglement of the quantum-bits are difficult to engineer. Here we investigate the possibility of using closely-spaced-linear arrays of metallic-elliptical discs as whispering gallery waveguides to control artificial-atoms. The discs confine and guide radiation through the array with small notches etched into their sides that act as scatterers. We focus on π-ring artificial-atoms, which can generate their own spontaneous fluxes. We find that the micro-discs of the waveguides can be excited by terahertz frequency fields to exhibit whispering-modes and that a quantum-phase-gate composed of π-rings can be operated under their influence. Furthermore, we gauge the level of entanglement through the concurrence measure and show that under certain magnetic conditions a series of entanglement sudden-deaths and revivals occur between the two qubits. This is important for understanding the stability and life-time of qubit operations using, for example, a phase gate in a hybrid of quantum technologies composed of control elements and artificial-atoms. PMID:27122353

  3. Planet formation in evolving protoplanetary discs

    OpenAIRE

    Alexander, Richard

    2013-01-01

    I attempt to summarize our knowledge of planet formation in evolving protoplanetary discs. I first review the physics of disc evolution and dispersal. For most of the disc lifetime evolution is driven by accretion and photoevaporation, and I discuss how the interplay between these processes shapes protoplanetary discs. I also discuss the observations that we use to test these models, and the major uncertainties that remain. I will then move on to consider planet formation and migration in evo...

  4. Proceedings: Fossil steam turbine disc cracking workshop

    Energy Technology Data Exchange (ETDEWEB)

    1991-04-01

    The objectives of the workshop were to review and consolidate the state of the art of cracking in fossil steam turbine discs; to identify further work needed to assist utilities in evaluating fossil turbine discs subject to SCC. Participants included 18 representatives from utilities, 12 representatives from equipment manufacturing organizations, and 5 consultants. Canadian, European, Japanese, and domestic organizations were represented. Topics included: A Review of GE Fossil Shrunk-On Wheel Stress Corrosion Cracking; Effects on Material and Environmental Factors on SCC of NiCrMoV Rotor Steels; SCC Experience of Shrunk On Discs; Studies on SCC For Steam Turbine Rotor and Disc; Advanced Disc-Type LP Turbine Rotors; Recent Experience of Stress Corrosion Cracking in the LP Discs of Fossil-Fired Reheat Turbines; Stress Corrosion of NiCrMoV LP Disc and Shaft Steels Under Cyclic Loading; NYIT'S Focused Approach for Ultrasonically Scanning Steam Turbine Discs; Probabilistic Assessment of Crack Initiation and Growth in Shrunk-On Discs; Low-Pressure Rotor Disc Cracking and Remaining Life Analysis; Assessment of Probability of Survival of Built Up LP Turbine Rotors With Discs Containing Semi-Circular Keyways; Electric Power Research Institute Turbine Disc Inspection Program; Fossil Turbine Disc Inspections--A Utility Dilemma; In-Service Accumulation of Chemicals in the Keyways and Their Effect on Stress Corrosion Cracking of Turbine Discs; Pitting and Compositional Effects on Stress Corrosion Cracking of Turbine Disc Steels; and TVA's Recent Experience With Inspection and Testing of Shrink-On Discs. Individual papers are processed separately for the data bases.

  5. Spontaneous regression of an intraspinal disc cyst

    Energy Technology Data Exchange (ETDEWEB)

    Demaerel, P.; Eerens, I.; Wilms, G. [University Hospital, Leuven (Belgium). Dept. of Radiology; Goffin, J. [Dept. of Neurosurgery, University Hospitals, Leuven (Belgium)

    2001-11-01

    We present a patient with a so-called disc cyst. Its location in the ventrolateral epidural space and its communication with the herniated disc are clearly shown. The disc cyst developed rapidly and regressed spontaneously. This observation, which has not been reported until now, appears to support focal degeneration with cyst formation as the pathogenesis. (orig.)

  6. Electromagnetic Levitation of a Disc

    Science.gov (United States)

    Valle, R.; Neves, F.; de Andrade, R., Jr.; Stephan, R. M.

    2012-01-01

    This paper presents a teaching experiment that explores the levitation of a disc of ferromagnetic material in the presence of the magnetic field produced by a single electromagnet. In comparison to the classical experiment of the levitation of a sphere, the main advantage of the proposed laboratory bench is that the uniform magnetic field…

  7. Artificial Enzymes, "Chemzymes"

    DEFF Research Database (Denmark)

    Bjerre, Jeannette; Rousseau, Cyril Andre Raphaël; Pedersen, Lavinia Georgeta M;

    2008-01-01

    Enzymes have fascinated scientists since their discovery and, over some decades, one aim in organic chemistry has been the creation of molecules that mimic the active sites of enzymes and promote catalysis. Nevertheless, even today, there are relatively few examples of enzyme models that...... successfully perform Michaelis-Menten catalysis under enzymatic conditions (i.e., aqueous medium, neutral pH, ambient temperature) and for those that do, very high rate accelerations are seldomly seen. This review will provide a brief summary of the recent developments in artificial enzymes, so called...... "Chemzymes", based on cyclodextrins and other molecules. Only the chemzymes that have shown enzyme-like activity that has been quantified by different methods will be mentioned. This review will summarize the work done in the field of artificial glycosidases, oxidases, epoxidases, and esterases, as well as...

  8. Lumbar Disc Degenerative Disease: Disc Degeneration Symptoms and Magnetic Resonance Image Findings

    OpenAIRE

    Saleem, Shafaq; Aslam, Hafiz Muhammad; Rehmani, Muhammad Asim Khan; Raees, Aisha; Alvi, Arsalan Ahmad; Ashraf, Junaid

    2013-01-01

    Study Design Cross sectional and observational. Purpose To evaluate the different aspects of lumbar disc degenerative disc disease and relate them with magnetic resonance image (MRI) findings and symptoms. Overview of Literature Lumbar disc degenerative disease has now been proven as the most common cause of low back pain throughout the world. It may present as disc herniation, lumbar spinal stenosis, facet joint arthropathy or any combination. Presenting symptoms of lumbar disc degeneration ...

  9. Spontaneous Regression of Herniated Lumbar Disc with New Disc Protrusion in the Adjacent Level

    OpenAIRE

    Hakan, Tayfun; Gürcan, Serkan

    2016-01-01

    Spontaneous regression of herniated lumbar discs was reported occasionally. The mechanisms proposed for regression of disc herniation are still incomplete. This paper describes and discusses a case of spontaneous regression of herniated lumbar discs with a new disc protrusion in the adjacent level. A 41-year-old man was admitted with radiating pain and numbness in the left lower extremity with a left posterolateral disc extrusion at L5-S1 level. He was admitted to hospital with low back pain ...

  10. The magnetorotational instability in debris-disc gas

    Science.gov (United States)

    Kral, Quentin; Latter, Henrik

    2016-09-01

    Debris discs are commonly swathed in gas, which can be observed in UV, in fine structure lines in FIR, and in resolved maps of CO emission. Carbon and oxygen are overabundant in such gas, but it is severely depleted in hydrogen. As a consequence, its ionization fraction is remarkably high, suggesting that magnetohydrodynamic (MHD) processes could be important. In particular, the gas may be subject to the magnetorotational instability (MRI), and indeed, recent modelling of β Pictoris requires an anomalous viscosity to explain the gas's observed radial structure. In this paper, we explore the possibility that the MRI is active in debris-disc gas and responsible for the observed mass transport. We find that non-ideal MHD and dust-gas interactions play a subdominant role, and that linear instability is viable at certain radii. However, owing to low gas densities, the outer parts of the disc could be stabilized by a weak ambient magnetic field, though it is difficult to constrain such a field. Even if the MRI is stabilized by too strong a field, a magnetocentrifugal wind may be launched in its place, and this could lead to equivalent (non-turbulent) transport. Numerical simulations of the vertically stratified MRI in conditions appropriate to the debris-disc gas should be able to determine the nature of the characteristic behaviour at different radii, and decide on the importance of the MRI (and MHD more generally) on the evolution of these discs.

  11. Engineered microporosity: enhancing the early regenerative potential of decellularized temporomandibular joint discs.

    Science.gov (United States)

    Juran, Cassandra M; Dolwick, M Franklin; McFetridge, Peter S

    2015-02-01

    The temporomandibular joint (TMJ) disc is susceptible to numerous pathologies that may lead to structural degradation and jaw dysfunction. The limited treatment options and debilitating nature of severe temporomandibular disorders has been the primary driving force for the introduction and development of TMJ disc tissue engineering as an approach to alleviate this important clinical issue. This study aimed to evaluate the efficacy of laser micropatterning (LMP) ex vivo-derived TMJ disc scaffolds to enhance cellular integration, a major limitation to the development of whole tissue implant technology. LMP was incorporated into the decellularized extracellular matrix scaffold structure using a 40 W CO2 laser ablation system to drill an 8×16 pattern with a bore diameter of 120 μm through the scaffold thickness. Disc scaffolds were seeded with human neonatal-derived umbilical cord mesenchymal stem cells differentiated into chondrocytes at a density of 900 cells per mm(2) and then assessed on days 1, 7, 14, and 21 of culture. Results derived from histology, PicoGreen DNA quantification, and cellular metabolism assays indicate that the LMP scaffolds improve cellular remodeling compared to the unworked scaffold over the 21-day culture period. Mechanical analysis further supports the use of the LMP showing the compressive properties of the LMP constructs closely represent native disc mechanics. The addition of an artificial path of infiltration by LMP culminated in improved chondrocyte adhesion, dispersion, and migration after extended culture aiding in recapitulating the native TMJ disc characteristics. PMID:25319941

  12. Disc degeneration: current surgical options

    Directory of Open Access Journals (Sweden)

    C Schizas

    2010-10-01

    Full Text Available Chronic low back pain attributed to lumbar disc degeneration poses a serious challenge to physicians. Surgery may be indicated in selected cases following failure of appropriate conservative treatment. For decades, the only surgical option has been spinal fusion, but its results have been inconsistent. Some prospective trials show superiority over usual conservative measures while others fail to demonstrate its advantages. In an effort to improve results of fusion and to decrease the incidence of adjacent segment degeneration, total disc replacement techniques have been introduced and studied extensively. Short-term results have shown superiority over some fusion techniques. Mid-term results however tend to show that this approach yields results equivalent to those of spinal fusion. Nucleus replacement has gained some popularity initially, but evidence on its efficacy is scarce. Dynamic stabilisation, a technique involving less rigid implants than in spinal fusion and performed without the need for bone grafting, represents another surgical option. Evidence again is lacking on its superiority over other surgical strategies and conservative measures. Insertion of interspinous devices posteriorly, aiming at redistributing loads and relieving pain, has been used as an adjunct to disc removal surgery for disc herniation. To date however, there is no clear evidence on their efficacy. Minimally invasive intradiscal thermocoagulation techniques have also been tried, but evidence of their effectiveness is questioned. Surgery using novel biological solutions may be the future of discogenic pain treatment. Collaboration between clinicians and basic scientists in this multidisciplinary field will undoubtedly shape the future of treating symptomatic disc degeneration.

  13. Evaluation of the kinesthetic sense and function of the hand in early period in operated cervical disc hernia

    OpenAIRE

    Kara, Býlge; Yildirim, Yücel; Karadýbak, Dýdem; Acar, Ümýt

    2005-01-01

    A prospective study made into cervical disc hernias. To determine the kinesthetic sense and hand functions, which are important for the patients with cervical disc hernia to return to work life and daily activities that need skill. Neurosurgical department. Data Symptoms in cervical disc hernias and hand functions are affected depending on long-term pain. The evaluation of the hand is essential in assessing the patients’ overall recovery and ability to return to daily activities and work life...

  14. CT findings of lumbar intervertebral disc: II. Disc herniation (HNP)

    International Nuclear Information System (INIS)

    In lumbar region the epidural fat pad is relatively abundant so that CT can provides sufficient information in diagnosis of lumbar HNP. Many authors have reported on the CT findings of HNP such as focal nodular protrusion of the posterior disc margin, obliteration of epidural fat pad, impingement of dural sac and nerve root, swelling of nerve root, soft tissue density in the spinal canal and calcification of disc. However there was so previous report describing incidence and reliability of the findings. It is the purpose of the present study to survey the frequency, reliability, and limitation of these CT findings. The clinical material was consisted of 30 operatively proven cases of HNP of the lumbar spine. Each lumbar CT scan was reviewed retrospectively and the findings were analysed by two radiologists independently. There were 20 males and 10 females and the mean age was 36.7 years. Involvement of L4-S5 level was 2.3 times more frequent than that of L5-S1 level. Of 30 cases, 22 were unilateral posterolateral types and 8 cases central or unilateral far lateral types. CT findings observed were nodular protrusion of the posterior margin of the disc, obliteration of epidural fat pad, impingement of dural sac or nerve root, soft tissue density in the spinal canal and calcification in the posterior portion of the protruded disc, in order of decreasing frequency. The conclusions are follows: 1. Nodular protrusion of the posterior disc margin accompanied by obliteration of epidural fat pad was observed in every case. The former findings was designated as direct sign and the latter indirect. 2. Obliteration of the epidural fat appears to be significant in lateral recesses especially when it occurs unilaterally. This was not true, however, in the centrally located fat pad. 3. Impingement of the dural sac and nerve root were observed in 90% and 67%, respectively, and were very helpful in establishing HNP diagnosis when the direct and indirect signs were equivocal

  15. MR imaging findings of a sequestered disc in the lumbar spine: a comparison with an extruded disc

    Energy Technology Data Exchange (ETDEWEB)

    Sim, Su Youn; Park, Ji Seon; Ryu, Kyung Nam [Kyung Hee University Medical Center, Seoul (Korea, Republic of); Jin, Wook [Kyung Hee University East-west Neo Medical Center, Seoul (Korea, Republic of)

    2007-10-15

    To compare the MR findings of a sequestered disc with an extruded disc. MR images of 28 patients with a sequestered disc and 18 patients with an extruded disc were retrospectively reviewed. Patients with sequestered discs were divided into two groups whether definite separation from the parent disc was or was not seen. In the latter group (definite separation not seen) and the extruded disc group of patients, the signal intensities of the herniated discs were compared with the signal intensities of the parent discs and were evaluated on T1-and T2-weighted images. We also assessed the presence of a notch within the herniated disc. In the sequestered disc group of patients (28 discs), only 5 discs (18%) showed obvious separation from the parent disc. Among the remaining 23 discs with indefinite separation, the notch was visible in 14 discs (61%) and 9 discs (39%) had no notch. In the extruded disc group (18 discs), the notch was visible in 2 (11%) discs and the difference between the two groups was statistically significant ({rho} 0.0002). The signal intensities of the herniated discs on T1-weighted images were isointense in both the sequestered and extruded discs. The difference of incidence of high signal intensities on T2-weighted images was not statistically significant ({rho} = 0.125). It is necessary to consider the possibility of the presence of a sequestered disc when a herniated disc material shows a notch.

  16. Testing hydrodynamics schemes in galaxy disc simulations

    Science.gov (United States)

    Few, C. G.; Dobbs, C.; Pettitt, A.; Konstandin, L.

    2016-08-01

    We examine how three fundamentally different numerical hydrodynamics codes follow the evolution of an isothermal galactic disc with an external spiral potential. We compare an adaptive mesh refinement code (RAMSES), a smoothed particle hydrodynamics code (sphNG), and a volume-discretised meshless code (GIZMO). Using standard refinement criteria, we find that RAMSES produces a disc that is less vertically concentrated and does not reach such high densities as the sphNG or GIZMO runs. The gas surface density in the spiral arms increases at a lower rate for the RAMSES simulations compared to the other codes. There is also a greater degree of substructure in the sphNG and GIZMO runs and secondary spiral arms are more pronounced. By resolving the Jeans' length with a greater number of grid cells we achieve more similar results to the Lagrangian codes used in this study. Other alterations to the refinement scheme (adding extra levels of refinement and refining based on local density gradients) are less successful in reducing the disparity between RAMSES and sphNG/GIZMO. Although more similar, sphNG displays different density distributions and vertical mass profiles to all modes of GIZMO (including the smoothed particle hydrodynamics version). This suggests differences also arise which are not intrinsic to the particular method but rather due to its implementation. The discrepancies between codes (in particular, the densities reached in the spiral arms) could potentially result in differences in the locations and timescales for gravitational collapse, and therefore impact star formation activity in more complex galaxy disc simulations.

  17. Treatment of lumbar disc herniation: Evidence-based practice

    Directory of Open Access Journals (Sweden)

    Andrew J Schoenfeld

    2010-07-01

    Full Text Available Andrew J Schoenfeld1, Bradley K Weiner21Department of Orthopedic Surgery, William Beaumont Army Medical Center, Texas Tech University Health Sciences Center, El Paso, TX, USA; 2Weill Cornell Medical College and The Methodist Hospital, Houston, TX, USAClinical question: What is the best treatment for lumbar disc herniations? Results: For patients failing six weeks of conservative care, the current literature supports surgical intervention or prolonged conservative management as appropriate treatment options for lumbar radiculopathy in the setting of disc herniation. Surgical intervention may result in more rapid relief of symptoms and restoration of function.Implementation: While surgery appears to provide more rapid relief, many patients will gradually get better with continued nonoperative management; thus, patient education and active participation in decision-making is vital.Keywords: lumbar disc, herniation, back pain, spine

  18. Accretion and plasma outflow from dissipationless discs

    OpenAIRE

    Bogovalov, Sergei; Kelner, Stanislav

    2008-01-01

    We consider an extreme case of disc accretion onto a gravitating centre when the viscosity in the disc is negligible. The angular momentum and the rotational energy of the accreted matter is carried out by a magnetized wind outflowing from the disc. The outflow of matter from the disc occurs due to the Blandford & Payne(1982) centrifugal mechanism. The disc is assumed to be cold. Accretion and outflow are connected by the conservation of the energy, mass and the angular momentum. The basic pr...

  19. On the warping of Be star discs

    OpenAIRE

    Porter, John M.

    1998-01-01

    The theory of radiatively-induced warps in accretion discs is applied to the discs of Be stars. It is found that these discs may develop warps in their inner regions, although once the warp amplitude is large enough then the interaction between the disc and fast radiatively-driven wind will determine its evolution. The warping is shown to be more important for later than earlier B stars. Although the interaction of the fast-wind with the disc will limit the amplitude of the warp, it cannot dr...

  20. Distribution of artificial gamma-ray emitting radionuclide activity concentration in the top soil in the vicinity of the Ignalina Nuclear Power Plant and other regions in Lithuania

    Energy Technology Data Exchange (ETDEWEB)

    Luksiene, Benedikta, E-mail: bena@ar.fi.lt [Center for Physical Sciences and Technology, Savanoriu ave. 231, LT-02300 Vilnius (Lithuania); Marciulioniene, Danute [Nature Research Centre, Akademijos str. 2, LT-08412 Vilnius (Lithuania); Rozkov, Andrej [PLL ' LOKMIS' Radiometry Department, Visoriu 2, LT-08300 Vilnius (Lithuania); Gudelis, Arunas [Center for Physical Sciences and Technology, Savanoriu ave. 231, LT-02300 Vilnius (Lithuania); Holm, Elis [Department of Medical Radiation Physics, Lund University Hospital, SE-22185 Lund (Sweden); Galvonaite, Audrone [Lithuanian Hydrometeorological Service under the Ministry of Environment, Rudnios str. 6, LT-09300 Vilnius (Lithuania)

    2012-11-15

    The impact of the operating Ignalina Nuclear Power Plant (INPP) on the contamination of top soil layer with artificial radionuclides has been studied. Results of the investigation of artificial gamma-ray emitting radionuclide distribution in soil in the vicinity of the INPP and distant regions in Lithuania in 1996-2008 (INPP operational period) show that nowadays {sup 137}Cs remains the most important artificial gamma-ray emitting radionuclide in the upper soil layer. Mean {sup 137}Cs activity concentrations in the top soil layer in the vicinity of the INPP were found to be significantly lower compared to those in remote regions of Varena and Plunge ({approx} 300 km from INPP). In 1996 and 1998 mean {sup 137}Cs activity concentrations were in the range of 28-45 Bq/kg in the nearest vicinity to the INPP, 103 Bq/kg in Varena and 340 Bq/kg in Plunge region. {sup 137}Cs activity concentrations were 5-20 times lower in meadow soil (4-14 Bq/kg) compared to swamp and forest soil. {sup 60}Co, the INPP origin radionuclide, was detected in samples only in 1996 and 2000, and the activity concentration of {sup 60}Co was found to be in the range from 0.4 to 7.0 Bq/kg at the sampling ground nearest to the INPP. Average annual activity concentrations of the INPP origin {sup 137}Cs and {sup 60}Co in the air and depositions in the INPP region were modeled using Pasquill-Gifford equations. The modeling results of {sup 137}Cs and {sup 60}Co depositional load in the INPP vicinity agree with the experimentally obtained values. Our results provide the evidence that the operation of INPP did not cause any significant contamination in soil surface. -- Highlights: Black-Right-Pointing-Pointer Gamma-emitters in top soil were studied during the operational period of the Ignalina NPP. Black-Right-Pointing-Pointer Only {sup 137}Cs was detected in each sample of the top soil in studied regions every year. Black-Right-Pointing-Pointer The mean {sup 137}Cs activity in the top soil of the INPP

  1. An Artificial Neural Network Controller for Three-level Shunt Active Filter to Eliminate the Current Harmonics and Compensate Reactive Power

    Directory of Open Access Journals (Sweden)

    Chennai Salim

    2011-09-01

    Full Text Available The increased use of nonlinear devices in the industry has resulted in the direct increase of harmonic distortion in power systems during these last years. Active filter systems are proposed to mitigate current harmonics generated by nonlinear loads. The conventional scheme based on a two-level voltage source inverter controlled by a hysteresis controller has several disadvantages and cannot be used for medium or high-power applications. To overcome these drawbacks and improve the APF performance, there’s a great tendency to use multilevel inverters controlled by intelligent controllers. Three level (NPC inverter is one of the most widely used topologies in various industrial applications such as machine drives and power factor compensators. On the other hand, artificial neural networks are under study and investigation in other power electronics applications. In order to gain the advantages of the three-level inverter and artificial neural networks and to reduce the complexity of classical control schemes, a new active power filter configuration controlled by two MLPNN (Multi-Layer Perceptron Neural Network is proposed in this paper. The first ANN is used to replace the PWM current controller, and the second one to maintain a constant dc link voltage across the capacitors and compensate the inverter power losses. The performance of the global system, including power and control circuits is evaluated by Matlab-Simulink and SimPowerSystem Toolbox simulation. The obtained results confirm the effectiveness of the proposed control scheme.

  2. Three-level cervical disc herniation

    Directory of Open Access Journals (Sweden)

    St. Iencean Andrei

    2015-09-01

    Full Text Available Multilevel cervical degenerative disc disease is well known in the cervical spine pathology, with radicular syndromes or cervical myelopathy. One or two level cervical herniated disc is common in adult and multilevel cervical degenerative disc herniation is common in the elderly, with spinal stenosis, and have the same cause: the gradual degeneration of the disc. We report the case of a patient with two level cervical disc herniation (C4 – C5 and C5 – C6 treated by anterior cervical microdiscectomy both levels and fusion at C5 – C6; after five years the patient returned with left C7 radiculopathy and MRI provided the image of a left C6 – C7 disc herniation, he underwent an anterior microsurgical discectomy with rapid relief of symptoms. Three-level cervical herniated disc are rare in adults, and the anterior microdiscectomy with or without fusion solve this pathology.

  3. Numerical simulations of disc-planet interactions

    CERN Document Server

    Paardekooper, Richard P Nelson Sijme-Jan

    2009-01-01

    The gravitational interaction between a protoplanetary disc and planetary sized bodies that form within it leads to the exchange of angular momentum, resulting in migration of the planets and possible gap formation in the disc for more massive planets. In this article, we review the basic theory of disc-planet interactions, and discuss the results of recent numerical simulations of planets embedded in protoplanetary discs. We consider the migration of low mass planets and recent developments in our understanding of so-called type I migration when a fuller treatment of the disc thermodynamics is included. We discuss the runaway migration of intermediate mass planets (so-called type III migration), and the migration of giant planets (type II migration) and the associated gap formation in the disc. The availability of high performance computing facilities has enabled global simulations of magnetised, turbulent discs to be computed, and we discuss recent results for both low and high mass planets embedded in such...

  4. An Analysis of Burst Disc Pressure Instability

    Energy Technology Data Exchange (ETDEWEB)

    S. L. Robinson; B. C. Odegard, Jr.; N. r. Moody; S. H. Goods

    2000-06-01

    During the development stage of the 1X Acorn burst disc, burst pressure test results exhibited an unexpected increase of 8 to 14% over times of 90--100 days from initial fabrication. This increase is a concern where design constraints require stability. The disc material, 316L stainless steel sheet, is formed to a dome-like geometry and scored to produce a thin-walled, high-strength ligament. The fracture events controlling burst occur in that ligament. Thus it has been characterized both for tensile properties and microstructure through nanoindentation, magnetic measurements, optical and transmission electron microscopy. These results compare favorably with finite element simulation of the properties of the ligament. The ligament exhibits a highly heterogeneous microstructure; its small volume and microstructural heterogeneity make it difficult to identify which microstructural feature controls fracture and hence burst pressure. Bulk mechanical test specimens were fabricated to emulate mid-ligament properties, and aged at both room and elevated temperatures to characterize and accelerate the temporal behavior of the burst disc. Property changes included yield and ultimate tensile strength increases, and fracture strain decreases with aging. Specimens were subjected to a reversion anneal identical to that given the burst disc to eliminate the martensite phase formed during rolling. Reversion-annealed samples exhibited no change in properties in room temperature or accelerated aging, showing that the reversion-anneal eliminated the aging phenomenon. Aging was analyzed in terms of diffusion controlled precipitate growth kinetics, showing that carbon migration to dislocations is consistent with the strength increases. A vacancy-assisted diffusion mechanism for carbon transport is proposed, giving rise to rapid aging, which replaces interstitial carbon diffusion until excess vacancies from deformation are consumed. Mechanical activation parameters in stress relaxation

  5. The growth of planets by pebble accretion in evolving protoplanetary discs

    Science.gov (United States)

    Bitsch, Bertram; Lambrechts, Michiel; Johansen, Anders

    2015-10-01

    The formation of planets depends on the underlying protoplanetary disc structure, which in turn influences both the accretion and migration rates of embedded planets. The disc itself evolves on time scales of several Myr, during which both temperature and density profiles change as matter accretes onto the central star. Here we used a detailed model of an evolving disc to determine the growth of planets by pebble accretion and their migration through the disc. Cores that reach their pebble isolation mass accrete gas to finally form giant planets with extensive gas envelopes, while planets that do not reach pebble isolation mass are stranded as ice giants and ice planets containing only minor amounts of gas in their envelopes. Unlike earlier population synthesis models, our model works without any artificial reductions in migration speed and for protoplanetary discs with gas and dust column densities similar to those inferred from observations. We find that in our nominal disc model, the emergence of planetary embryos preferably should occur after approximately 2 Myr in order to not exclusively form gas giants, but also ice giants and smaller planets. The high pebble accretion rates ensure that critical core masses for gas accretion can be reached at all orbital distances. Gas giant planets nevertheless experience significant reduction in semi-major axes by migration. Considering instead planetesimal accretion for planetary growth, we show that formation time scales are too long to compete with the migration time scales and the dissipation time of the protoplanetary disc. All in all, we find that pebble accretion overcomes many of the challenges in the formation of ice and gas giants in evolving protoplanetary discs. Appendices are available in electronic form at http://www.aanda.org

  6. Determination of the intervertebral disc space from CT images of the lumbar spine

    Science.gov (United States)

    Korez, Robert; Å tern, Darko; Likar, Boštjan; Pernuš, Franjo; Vrtovec, Tomaž

    2014-03-01

    Degenerative changes of the intervertebral disc are among the most common causes of low back pain, where for individuals with significant symptoms surgery may be needed. One of the interventions is the total disc replacement surgery, where the degenerated disc is replaced by an artificial implant. For designing implants with good bone contact and continuous force distribution, the morphology of the intervertebral disc space and vertebral body endplates is of considerable importance. In this study we propose a method for the determination of the intervertebral disc space from three-dimensional (3D) computed tomography (CT) images of the lumbar spine. The first step of the proposed method is the construction of a model of vertebral bodies in the lumbar spine. For this purpose, a chain of five elliptical cylinders is initialized in the 3D image and then deformed to resemble vertebral bodies by introducing 25 shape parameters. The parameters are obtained by aligning the chain to the vertebral bodies in the CT image according to image intensity and appearance information. The determination of the intervertebral disc space is finally achieved by finding the planes that fit the endplates of the obtained parametric 3D models, and placing points in the space between the planes of adjacent vertebrae that enable surface reconstruction of the intervertebral disc space. The morphometric analysis of images from 20 subjects yielded 11:3 +/- 2:6, 12:1 +/- 2:4, 12:8 +/- 2:0 and 12:9 +/- 2:7 cm3 in terms of L1-L2, L2-L3, L3-L4 and L4-L5 intervertebral disc space volume, respectively.

  7. Curcuma DMSO extracts and curcumin exhibit an anti-inflammatory and anti-catabolic effect on human intervertebral disc cells, possibly by influencing TLR2 expression and JNK activity

    Directory of Open Access Journals (Sweden)

    Klawitter Marina

    2012-08-01

    Full Text Available Abstract Background As proinflammatory cytokines seem to play a role in discogenic back pain, substances exhibiting anti-inflammatory effects on intervertebral disc cells may be used as minimal-invasive therapeutics for intradiscal/epidural injection. The purpose of this study was to investigate the anti-inflammatory and anti-catabolic potential of curcuma, which has been used in the Indian Ayurvedic medicine to treat multiple ailments for a long time. Methods Human disc cells were treated with IL-1β to induce an inflammatory/catabolic cascade. Different extracts of curcuma as well as curcumin (= a component selected based on results with curcuma extracts and HPLC/MS analysis were tested for their ability to reduce mRNA expression of proinflammatory cytokines and matrix degrading enzymes after 6 hours (real-time RT-PCR, followed by analysis of typical inflammatory signaling mechanisms such as NF-κB (Western Blot, Transcription Factor Assay, MAP kinases (Western Blot and Toll-like receptors (real-time RT-PCR. Quantitative data was statistically analyzed using a Mann Whitney U test with a significance level of p  Results Results indicate that the curcuma DMSO extract significantly reduced levels of IL-6, MMP1, MMP3 and MMP13. The DMSO-soluble component curcumin, whose occurrence within the DMSO extract was verified by HPLC/MS, reduced levels of IL-1β, IL-6, IL-8, MMP1, MMP3 and MMP13 and both caused an up-regulation of TNF-α. Pathway analysis indicated that curcumin did not show involvement of NF-κB, but down-regulated TLR2 expression and inhibited the MAP kinase JNK while activating p38 and ERK. Conclusions Based on its anti-inflammatory and anti-catabolic effects, intradiscal injection of curcumin may be an attractive treatment alternative. However, whether the anti-inflammatory properties in vitro lead to analgesia in vivo will need to be confirmed in an appropriate animal model.

  8. DISC1 knockdown impairs the tangential migration of cortical interneurons by affecting the actin cytoskeleton

    Directory of Open Access Journals (Sweden)

    Jürgen Bolz

    2014-07-01

    Full Text Available Disrupted-in-Schizophrenia 1 (DISC1 is a risk gene for a spectrum of major mental disorders. It has been shown to regulate radial migration as well as dendritic arborization during neurodevelopment and corticogenesis. In a previous study we demonstrated through in vitro experiments that DISC1 also controls the tangential migration of cortical interneurons originating from the medial ganglionic eminence (MGE. Here we first show that DISC1 is necessary for the proper tangential migration of cortical interneurons in the intact brain. Expression of EGFP under the Lhx6 promotor allowed us to analyze exclusively interneurons transfected in the MGE after in utero electroporation. After 3 days in utero, DISC1 deficient interneurons displayed prolonged leading processes and, compared to control, fewer neurons reached the cortex. Time-lapse video microscopy of cortical feeder-layers revealed a decreased migration velocity due to a reduction of soma translocations. Immunostainings indicated that DISC1 is co-localized with F-actin in the growth cone-like structure of the leading process. DISC1 knockdown reduced F-actin levels whereas the overall actin level was not altered. Moreover, DISC1 knockdown also decreased levels of phosphorylated Girdin, which cross-links F-actin, as well as the Girdin-activator pAkt. In contrast, using time-lapse video microscopy of fluorescence-tagged tubulin and EB3 in fibroblasts, we found no effects on microtubule polymerization when DISC1 was reduced. However, DISC1 affected the acteylation of microtubules in the leading processes of MGE-derived cortical interneurons. Together, our results provide a mechanism how DISC1 might contribute to interneuron migration thereby explaining the reduced number of specific classes of cortical interneurons in some DISC1 mouse models.

  9. Operative Management of Lumbar Degenerative Disc Disease.

    Science.gov (United States)

    Lee, Yu Chao; Zotti, Mario Giuseppe Tedesco; Osti, Orso Lorenzo

    2016-08-01

    Lumbar degenerative disc disease is extremely common. Current evidence supports surgery in carefully selected patients who have failed non-operative treatment and do not exhibit any substantial psychosocial overlay. Fusion surgery employing the correct grafting and stabilization techniques has long-term results demonstrating successful clinical outcomes. However, the best approach for fusion remains debatable. There is some evidence supporting the more complex, technically demanding and higher risk interbody fusion techniques for the younger, active patients or patients with a higher risk of non-union. Lumbar disc arthroplasty and hybrid techniques are still relatively novel procedures despite promising short-term and mid-term outcomes. Long-term studies demonstrating superiority over fusion are required before these techniques may be recommended to replace fusion as the gold standard. Novel stem cell approaches combined with tissue engineering therapies continue to be developed in expectation of improving clinical outcomes. Results with appropriate follow-up are not yet available to indicate if such techniques are safe, cost-effective and reliable in the long-term. PMID:27559465

  10. Operative Management of Lumbar Degenerative Disc Disease

    Science.gov (United States)

    Lee, Yu Chao; Osti, Orso Lorenzo

    2016-01-01

    Lumbar degenerative disc disease is extremely common. Current evidence supports surgery in carefully selected patients who have failed non-operative treatment and do not exhibit any substantial psychosocial overlay. Fusion surgery employing the correct grafting and stabilization techniques has long-term results demonstrating successful clinical outcomes. However, the best approach for fusion remains debatable. There is some evidence supporting the more complex, technically demanding and higher risk interbody fusion techniques for the younger, active patients or patients with a higher risk of non-union. Lumbar disc arthroplasty and hybrid techniques are still relatively novel procedures despite promising short-term and mid-term outcomes. Long-term studies demonstrating superiority over fusion are required before these techniques may be recommended to replace fusion as the gold standard. Novel stem cell approaches combined with tissue engineering therapies continue to be developed in expectation of improving clinical outcomes. Results with appropriate follow-up are not yet available to indicate if such techniques are safe, cost-effective and reliable in the long-term. PMID:27559465

  11. Artificial Economy

    Directory of Open Access Journals (Sweden)

    Alexandru JIVAN

    2011-08-01

    Full Text Available This paper proposes to eliminate, a routine in the economic thinking, claimed to be responsible for the negative essence of economic developments, from the point of view, of the ecological implications (employment in the planetary ecosystem. The methodological foundations start from the natural origins of the functionality of the human economic society according to the originary physiocrat liberalism, and from specific natural characteristics of the humankind. This paper begins with a comment-analysis of the difference between natural and artificial within the economy, and then explains some of the most serious diversions from the natural essence of economic liberalism. It shall be explained the original (heterodox interpretation of the Classical political economy (economics, by making calls to the Romanian economic thinking from aggravating past century. Highlighting the destructive impact of the economy - which, under the invoked doctrines, we call unnatural - allows an intuitive presentation of a logical extension of Marshall's market price, based on previous research. Besides the doctrinal arguments presented, the economic realities inventoried along the way (major deficiencies and effects, determined demonstrate the validity of the hypothesis of the unnatural character and therefore necessarily to be corrected, of the concept and of the mechanisms of the current economy.The results of this paper consist of original heterodox methodspresented, intuitive or developed that can be found conclusively within the key proposals for education and regulation.

  12. Reoperations Following Cervical Disc Replacement

    OpenAIRE

    Skovrlj, Branko; Lee, Dong-Ho; Caridi, John Michael; Cho, Samuel Kang-Wook

    2015-01-01

    Cervical disc replacement (CDR) has emerged as an alternative surgical option to cervical arthrodesis. With increasing numbers of patients and longer follow-ups, complications related to the device and/or aging spine are growing, leaving us with a new challenge in the management and surgical revision of CDR. The purpose of this study is to review the current literature regarding reoperations following CDR and to discuss about the approaches and solutions for the current and future potential c...

  13. Grain charging in protoplanetary discs

    OpenAIRE

    Ilgner, Martin

    2011-01-01

    Recent work identified a growth barrier for dust coagulation that originates in the electric repulsion between colliding particles. Depending on its charge state, dust material may have the potential to control key processes towards planet formation such as MHD (magnetohydrodynamic) turbulence and grain growth which are coupled in a two-way process. We quantify the grain charging at different stages of disc evolution and differentiate between two very extreme cases: compact spherical grains a...

  14. Gravitating discs around black holes

    Czech Academy of Sciences Publication Activity Database

    Karas, Vladimír; Huré, J.-M.; Semerák, O.

    2004-01-01

    Roč. 21, č. 7 (2004), R1-R5. ISSN 0264-9381 R&D Projects: GA ČR GA205/03/0902; GA AV ČR KSK1048102 Institutional research plan: CEZ:AV0Z1003909 Keywords : black holes * accretion discs * general relativity Subject RIV: BN - Astronomy, Celestial Mechanics, Astrophysics Impact factor: 2.941, year: 2004

  15. The dispersal of protoplanetary discs

    Directory of Open Access Journals (Sweden)

    Ercolano Barbara

    2013-04-01

    Full Text Available Protoplanetary discs are a natural consequence of the star formation process and as such are ubiquitous around low-mass stars. They are fundamental to planet formation as they hold the reservoir of material from which planets form. Their evolution and final dispersal and the timescales that regulate these process are therefore of particular interest. In this contribution I will review the observational evidence for the dispersal of discs being dominated by two timescales and for the final dispersal to occur quickly and from the inside out. I will discuss the current theoretical models, including X-ray photoevaporation, showing that the latter provides a natural explanation to the observed behaviour and review supporting and contrasting evidence. I will finally introduce a new mechanism based on the interaction between planet formation and photoevaporation that may explain a particular class of transition discs with large inner holes and high accretion rates that are problematic for photoevaporation models and planet formation models alone.

  16. Development of a method for quantitative measures of lumbar intervertebral disc structures

    DEFF Research Database (Denmark)

    Tunset, Andreas; Kjær, Per; Chreiteh, Shadi Samir;

    2013-01-01

    applicable description of quantitative methods for measuring lumbar disc herniations and related structures on sagittal MRIs. The objectives of this study were: 1) to develop methods for quantitative measures of intervertebral discs, lumbar disc herniations and dural sac/spinal canal using MRIs, 2) to......Background: Detailed information about the development of disc morphology over time could provide valuable knowledge about disc health when compared with clinical measures such as pain and activity limitation. However, a review of the available literature did not reveal any detailed and directly...... evaluate the agreement of these methods, and 3) to identify factors in the measurement procedures that may compromise agreement. Methods: In this intra- and inter-rater agreement study, lumbar quantitative measurements were performed on magnetic resonance images from 32 participants from a study cohort...

  17. Optic Disc Imaging by Heidelberg Retinal Tomogram in Congenital Optic Disc Anomaly

    OpenAIRE

    Kunjam Vallam; Sekhar G

    2004-01-01

    We evaluated two cases of congenital optic disc anomaly with the Heidelberg Retinal Tomograph (HRT) that could be mistaken for glaucomatous optic disc. One was an optic disc coloboma with a visual field defect and the other had an optic disc pit without a visual field defect. HRT was abnormal only in the eye with optic disc pit with normal fields. While HRT can be a valuable adjunct to disc evaluation and follow-up, it cannot be used in isolation in the differentiation of abnormal from normal...

  18. Fluctuating Activity Of Artificial Radioisotopes Caused By Accident At Fukushima-I Nuclear Power Plant In Air At The South Of Vietnam

    International Nuclear Information System (INIS)

    March 11, 2011, a powerful earthquake in the history of Japan (9 degrees richter) occurred in Sendai city located on the east coast of Honshu. This disaster even more serious by the tsunami appeared in the east coast of Japan. A day later, the incident happened at the Fukushima-I nuclear power plant with complex evolution. A large number of radioisotopes have ejected air, and long range spread was recorded in almost all stations of the CTBTO in the northern hemisphere. Two weeks after the incident, radioactive anomalies were detected in the air at Da Lat, Ninh Thuan and Ho Chi Minh City. Results of monitoring the changes in the activity of the artificial radioisotopes 131I, 134Cs and 137Cs in aerosols are presented. Evolutions 137Cs/134Cs isotope ratios in aerosols in Da Lat, Ninh Thuan and Ho Chi Minh City have been evaluated and the average value close to their isotopic ratios in aerosols at JPP38 station. This means that the source of the artificial radioisotopes identified in the south of our country is due to Fukushima-1 accident caused. (author)

  19. Multi-bioindicators to assess soil microbial activity in the context of an artificial groundwater recharge with treated wastewater: a large-scale pilot experiment.

    Science.gov (United States)

    Michel, Caroline; Joulian, Catherine; Ollivier, Patrick; Nyteij, Audrey; Cote, Rémi; Surdyk, Nicolas; Hellal, Jennifer; Casanova, Joel; Besnard, Katia; Rampnoux, Nicolas; Garrido, Francis

    2014-06-28

    In the context of artificial groundwater recharge, a reactive soil column at pilot-scale (4.5 m depth and 3 m in diameter) fed by treated wastewater was designed to evaluate soil filtration ability. Here, as a part of this project, the impact of treated wastewater filtration on soil bacterial communities and the soil's biological ability for wastewater treatment as well as the relevance of the use of multi-bioindicators were studied as a function of depth and time. Biomass; bacterial 16S rRNA gene diversity fingerprints; potential nitrifying, denitrifying, and sulfate-reducing activities; and functional gene (amo, nir, nar, and dsr) detection were analyzed to highlight the real and potential microbial activity and diversity within the soil column. These bioindicators show that topsoil (0 to 20 cm depth) was the more active and the more impacted by treated wastewater filtration. Nitrification was the main activity in the pilot. No sulfate-reducing activity or dsr genes were detected during the first 6 months of wastewater application. Denitrification was also absent, but genes of denitrifying bacteria were detected, suggesting that the denitrifying process may occur rapidly if adequate chemical conditions are favored within the soil column. Results also underline that a dry period (20 days without any wastewater supply) significantly impacted soil bacterial diversity, leading to a decrease of enzyme activities and biomass. Finally, our work shows that treated wastewater filtration leads to a modification of the bacterial genetic and functional structures in topsoil. PMID:24608565

  20. Proto-planetary disc evolution and dispersal

    Science.gov (United States)

    Rosotti, Giovanni Pietro

    2015-05-01

    Planets form from gas and dust discs in orbit around young stars. The timescale for planet formation is constrained by the lifetime of these discs. The properties of the formed planetary systems depend thus on the evolution and final dispersal of the discs, which is the main topic of this thesis. Observations reveal the existence of a class of discs called "transitional", which lack dust in their inner regions. They are thought to be the last stage before the complete disc dispersal, and hence they may provide the key to understanding the mechanisms behind disc evolution. X-ray photoevaporation and planet formation have been studied as possible physical mechanisms responsible for the final dispersal of discs. However up to now, these two phenomena have been studied separately, neglecting any possible feedback or interaction. In this thesis we have investigated what is the interplay between these two processes. We show that the presence of a giant planet in a photo-evaporating disc can significantly shorten its lifetime, by cutting the inner regions from the mass reservoir in the exterior of the disc. This mechanism produces transition discs that for a given mass accretion rate have larger holes than in models considering only X-ray photo-evaporation, constituting a possible route to the formation of accreting transition discs with large holes. These discs are found in observations and still constitute a puzzle for the theory. Inclusion of the phenomenon called "thermal sweeping", a violent instability that can destroy a whole disc in as little as 10 4 years, shows that the outer disc left can be very short-lived (depending on the X-ray luminosity of the star), possibly explaining why very few non accreting transition discs are observed. However the mechanism does not seem to be efficient enough to reconcile with observations. In this thesis we also show that X-ray photo-evaporation naturally explains the observed correlation between stellar masses and accretion

  1. Microfluidic active mixers employing ultra-high aspect-ratio rare-earth magnetic nano-composite polymer artificial cilia

    International Nuclear Information System (INIS)

    We present a new micromixer based on highly magnetic, flexible, high aspect-ratio, artificial cilia that are fabricated as individual micromixer elements or in arrays for improved mixing performance. These new cilia enable high efficiency, fast mixing in a microchamber, and are controlled by small electromagnetic fields. The artificial cilia are fabricated using a new micromolding process for nano-composite polymers. Cilia fibers with aspect-ratios as high as 8:0.13 demonstrate the fabrication technique's capability in creating ultra-high aspect-ratio microstructures. Cilia, which are realized in polydimethylsiloxane doped with rare-earth magnetic powder, are magnetized to produce permanent magnetic structures with bidirectional deflection capabilities, making them highly suitable as mixers controlled by electromagnetic fields. Due to the high magnetization level of the polarized nano-composite polymer, we are able to use miniature electromagnets providing relatively small magnetic fields of 1.1 to 7 mT to actuate the cilia microstructures over a very wide motion range. Mixing performances of a single cilium, as well as different arrays of multiple cilia ranging from 2 to 8 per reaction chamber, are characterized and compared with passive diffusion mixing performance. The mixer cilia are actuated at different amplitudes and frequencies to optimize mixing performance. We demonstrate that more than 85% of the total volume of the reaction chamber is fully mixed after 3.5 min using a single cilium mixer at 7 mT compared with only 20% of the total volume mixed with passive diffusion. The time to achieve over 85% mixing is further reduced to 70 s using an array of eight cilia microstructures. The novel microfabrication technique and use of rare-earth permanently-magnetizable nano-composite polymers in mixer applications has not been reported elsewhere by other researchers. We further demonstrate improved mixing over other cilia micromixers as enabled by the high

  2. Lifestyle factors and lumbar disc disease : results of a German multi-center case-control study (EPILIFT).

    OpenAIRE

    Schumann, Barbara; Bolm-Audorff, Ulrich; Bergmann, Annekatrin; Ellegast, Rolf; Elsner, Gine; Grifka, Joachim; Haerting, Johannes; Jäger, Matthias; Michaelis, Martina; Seidler, Andreas

    2010-01-01

    INTRODUCTION: In the large-scale case-control study EPILIFT, we investigated the dose-response relationship between lifestyle factors (weight, smoking amount, cumulative duration of different sports activities) and lumbar disc disease. METHODS: In four German study regions (Frankfurt am Main, Freiburg, Halle/Saale, Regensburg), 564 male and female patients with lumbar disc herniation and 351 patients with lumbar disc narrowing (chondrosis) aged 25 to 70 years were prospectively recruited. Fro...

  3. DISC1 regulates astrogenesis in the embryonic brain via modulation of RAS/MEK/ERK signaling through RASSF7.

    Science.gov (United States)

    Wang, Shukun; Liang, Qingli; Qiao, Huimin; Li, Hong; Shen, Tianjin; Ji, Fen; Jiao, Jianwei

    2016-08-01

    Disrupted in schizophrenia 1 (DISC1) is known as a high susceptibility gene for schizophrenia. Recent studies have indicated that schizophrenia might be caused by glia defects and dysfunction. However, there is no direct evidence of a link between the schizophrenia gene DISC1 and gliogenesis defects. Thus, an investigation into the involvement of DISC1 (a ubiquitously expressed brain protein) in astrogenesis during the late stage of mouse embryonic brain development is warranted. Here, we show that suppression of DISC1 expression represses astrogenesis in vitro and in vivo, and that DISC1 overexpression substantially enhances the process. Furthermore, mouse and human DISC1 overexpression rescued the astrogenesis defects caused by DISC1 knockdown. Mechanistically, DISC1 activates the RAS/MEK/ERK signaling pathway via direct association with RASSF7. Also, the pERK complex undergoes nuclear translocation and influences the expression of genes related to astrogenesis. In summary, our results demonstrate that DISC1 regulates astrogenesis by modulating RAS/MEK/ERK signaling via RASSF7 and provide a framework for understanding how DISC1 dysfunction might lead to neuropsychiatric diseases. PMID:27287808

  4. Do We Need Biomarkers for Disc Degeneration?

    Directory of Open Access Journals (Sweden)

    Helen E. Gruber

    2006-01-01

    Full Text Available Disc degeneration plays a major role in this country's medical, social and economic structure. The life-time prevalence of low back pain, which has disc degeneration as its cause, is about 80% in the general population. It is a primary cause of disability and estimated costs related to low back disorders exceed $100 billion per year in the U.S. alone. Biomarkers are becoming increasingly important as indicators of the presence of disease, and in evaluating outcomes during clinical treatment. Cell-based biologic therapies which are currently being developed to treat disc degeneration are going to be most efficacious when applied to the early stages of disc disease. In this article we ask: 1 Whether there are existing biomarkers which could play a role in detecting early stages of disc degeneration, and 2 Highlight exciting potentials in future biomarker screening for disc degeneration.

  5. Stability and Evolution of Galactic Discs

    OpenAIRE

    Sellwood, J. A.

    1999-01-01

    In this review, I discuss just three aspects of the stability and evolution of galactic discs. (1) I first review our understanding of the bar instability and how it can be controlled. Disc galaxies in which the orbital speed does not decrease much towards the centre have no difficulty avoiding bars, even when dark matter makes an insignificant contribution to the inner part of the rotation curve. (2) I then briefly discuss interactions between disturbances in the discs of galaxies and the sp...

  6. CFD design analysis of ventilated disc brakes

    OpenAIRE

    Pulugundla, Gautam

    2008-01-01

    This thesis reports the numerical investigation of the automotive ventilated disc brake rotor. Disc brakes operate on the principle of friction by converting kinetic energy into heat energy. The main objective of a disc brake rotor is to store this heat energy and dissipate it as soon as possible. This work is carried out in a area where there is very limited understanding. Commercial CFD code FLUENT was used for carrying out the simulations with the rotor rotating in still ...

  7. Black hole feedback from thick accretion discs

    OpenAIRE

    Sadowski, Aleksander; Lasota, Jean-Pierre; Abramowicz, Marek A.; Narayan, Ramesh

    2015-01-01

    We study energy flows in geometrically thick accretion discs, both optically thick and thin, using general relativistic, three-dimensional simulations of black hole accretion flows. We find that for non-rotating black holes the efficiency of the total feedback from thick accretion discs is $3\\%$ - roughly half of the thin disc efficiency. This amount of energy is ultimately distributed between outflow and radiation, the latter scaling weakly with the accretion rate for super-critical accretio...

  8. Self-similar relativistic discs with pressure

    International Nuclear Information System (INIS)

    Solutions for discs in equilibrium specified by a constant velocity of rotation and constant velocity dispersions are found. The fluid is not perfect because the stress tensor is anisotropic. These discs are self-similar if they are of infinite extent. The solutions are exact when an equal number of particles move in each sense of rotation so that there is no dragging of the inertial frames. For discs rotating with the small velocity a WKB approximation is used to obtain solutions. (author)

  9. DSC Study of Collagen in Disc Disease

    OpenAIRE

    S. Skrzyński; Sionkowska, A.; A. Marciniak

    2010-01-01

    Differential scanning calorimetry (DSC) has been used to estimate the effect of disc disease on the collagen helix-coil transition and morphology for tissue extracted from patients during surgical operation. Forty discs were obtained from patients with degenerative disc disease undergoing surgery for low back pain. The patients were in the age between 20 and 70 years old. The specimens were kept wet during DSC experiment. The data allow the comparison between thermal stability of collagen ti...

  10. Physiological pattern of lumbar disc height

    International Nuclear Information System (INIS)

    Purpose of this study is to present a new method of quantifying objectively the height of all discs in lateral radiographs of the lumbar spine and of analysing the normal craniocaudal sequence pattern of lumbar disc heights. Methods: The new parameter is the ventrally measured disc height corrected for the dependence on the angle of lordosis by normalisation to mean angles observed in the erect posture of healthy persons. To eliminate radiographic magnification, the corrected ventral height is related to the mean depth of the cranially adjoining vertebra. In this manner lumbar disc heights were objectively measured in young, mature and healthy persons (146 males and 65 females). The craniocaudal sequence pattern was analysed by mean values from all persons and by height differences of adjoining discs in each individual lumbar spine. Results: Mean normative values demonstrated an increase in disc height between L1/L2 and L4/L5 and a constant or decreasing disc height between L4/L5 and L5/S1. However, this 'physiological sequence of disc height in the statistical mean' was observed in only 36% of normal males and 55% of normal females. Conclusion: The radiological pattern of the 'physiological sequence of lumbar disc height' leads to a relevant portion of false positive pathological results especially at L4/L5. An increase of disc height from L4/L5 to L5/S1 may be normal. The recognition of decreased disc height should be based on an abrupt change in the heights of adjoining discs and not on a deviation from a craniocaudal sequence pattern. (orig.)

  11. Propeller outflows from an MRI disc

    OpenAIRE

    Lii, Patrick S.; Romanova, Marina M.; Ustyugova, Galina V.; Koldoba, Alexander V.; Lovelace, Richard V. E.

    2013-01-01

    We present the results of axisymmetric simulations of MRI-driven accretion onto a rapidly rotating, magnetized star accreting in the propeller regime. The stellar magnetosphere corotates with the star, forming a centrifugal barrier at the disc-magnetosphere boundary which inhibits matter accretion onto the star. Instead, the disc matter accumulates at the disc-magnetosphere interface and slowly diffuses into the inner magnetosphere where it picks up angular momentum and is quickly ejected fro...

  12. Debris disc formation induced by planetary growth

    OpenAIRE

    Kobayashi, Hiroshi; Loehne, Torsten

    2014-01-01

    Several hundred stars older than 10 million years have been observed to have infrared excesses. These observations are explained by dust grains formed by the collisional fragmentation of hidden planetesimals. Such dusty planetesimal discs are known as debris discs. In a dynamically cold planetesimal disc, collisional coagulation of planetesimals produces planetary embryos which then stir the surrounding leftover planetesimals. Thus, the collisional fragmentation of planetesimals that results ...

  13. Computed tomography in the diagnosis of the lumbar disc herniation

    Energy Technology Data Exchange (ETDEWEB)

    Iwakura, Yuichiro (Yatsushiro General Hospital, Kumamoto (Japan)); Hayashi, Yasuo; Suzuki, Mutsuaki; Uemura, Mitsuharu; Fukuda, Kazuyuki; Koito, Hirofumi

    1984-06-01

    In this study, effectiveness of computed tomography (CT) in diagnosing lumbar disc herniation was evaluated. Twenty CT examinations which were interpreted as positive for a herniated disc, and were comfirmed by myelography, were reviewed. In 19 patients, CT demonstrated posterior protrusion of the disc but in one normal disc. Three typical cases were described. This study suggests that CT accurately demonstrates lumbar disc herniation.

  14. Designing mucoadhesive discs containing stem bark extract of Ziziphus jujuba based on Iranian traditional documents

    Directory of Open Access Journals (Sweden)

    Shokouhsadat Hamedi

    2016-03-01

    Results: Discs showed excellent mucoadhesion and released high amount of the active ingredients (47% immediately and completed after approximately the first hour. They had a good adhesion in buccal cavity. Conclusion:This study showed that the kinetics of release of the active substance from the mucoadhesive disc obeyed the zero order kinetic and didn’t follow the fick’s law. The water uptake and dissolution (DS, increased with the passing of time.

  15. NASA GES DISC Hurricane Web Portal

    Science.gov (United States)

    Liu, Z.; Leptoukh, G.; Ostrenga, D.; Rui, H.; Hulka, J.; Carlaw, L.

    2006-12-01

    This presentation will describe recent activities at the NASA Goddard Earth Sciences (GES) Data and Information Services Center (DISC) to support hurricane monitoring, research and outreach activities. A newly developed web portal (URL: http://disc.sci.gsfc.nasa.gov/hurricane/) is designed for viewing and studying hurricanes by utilizing various measurements by NASA remote-sensing instruments. The portal consists of five main components: - Current conditions (in pre-selected regions and updated daily): the latest maps, animation and profiles from NASA satellites. At present, images or plots created using data from TRMM, AIRS, MODIS, MLS and CloudSat are available. Later, data from OMI and other instruments will be added. A new feature will be added to allow users to easily download/subset data associated with these images. - Past hurricane archive: maps, animation and profiles of past hurricanes were created using data from TRMM, AIRS, MODIS, MLS and CloudSat, allowing users to explore past hurricanes and download/subset data if necessary. - Science focus: examples/stories describing data usage in hurricane monitoring and research - Tools: descriptions and links of a number of in-house developed tools for hurricane exploration and event-based data ordering. For example, the GES-DISC Interactive Online Visualization ANd aNalysis Infrastructure (Giovanni, URL: http://giovanni.gsfc.nasa.gov), a series of online visualization and analysis systems, allows users to access data ranging from near-real-time to historical archives and generate customized analysis maps, plots and data on the fly over the Internet. A hurricane instance of Giovanni is under development. Mirador (URL: http://g0dup05u.ecs.nasa.gov/OPS/mirador/) is another in-house developed tool that offers a simplified interface for searching, browsing, and ordering Earth science data at NASA GES DICS. Users can do event based (e.g., entering a hurricane name) search and order data. - Hurricane viewer: provides

  16. Long-term outcome after implantation of prosthetic disc nucleus device (PDN) in lumbar disc disease

    OpenAIRE

    Selviaridis, P; Foroglou, N; Tsitlakidis, A; Hatzisotiriou, A; Magras, I; Patsalas, I

    2010-01-01

    Background: The prosthetic disc nucleus (PDN) device offers an adjunct treatment for patients with degenerative disc disease and herniation, who necessitate surgical intervention, avoiding total-disc replacement or fusion. This prospective, clinical study aimed to gauge the long-term effectiveness of microdiscectomy followed by PDN implantation in relieving pain and improving functional status in patients with symptomatic degenerative lumbar disc disease and herniation.

  17. The quiescent phase of galactic disc growth

    Science.gov (United States)

    Aumer, Michael; Binney, James; Schönrich, Ralph

    2016-07-01

    We perform a series of controlled N-body simulations of growing disc galaxies within non-growing, live dark matter haloes of varying mass and concentration. Our initial conditions include either a low-mass disc or a compact bulge. New stellar particles are continuously added on near-circular orbits to the existing disc, so spiral structure is continuously excited. To study the effect of combined spiral and giant molecular cloud (GMC) heating on the discs, we introduce massive, short-lived particles that sample a GMC mass function. An isothermal gas component is introduced for a subset of the models. We perform a resolution study and vary parameters governing the GMC population, the histories of star formation and radial scale growth. Models with GMCs and standard values for the disc mass and halo density provide the right level of self-gravity to explain the age-velocity dispersion relation of the solar neighbourhood (Snhd). GMC heating generates remarkably exponential vertical profiles with scaleheights that are radially constant and agree with observations of galactic thin discs. GMCs are also capable of significantly delaying bar formation. The amount of spiral-induced radial migration agrees with what is required for the metallicity distribution of the Snhd. However, in our standard models, the outward-migrating populations are not hot enough vertically to create thick discs. Thick discs can form in models with high baryon fractions, but the corresponding bars are too long, the young stellar populations too hot and the discs flare considerably.

  18. The quiescent phase of galactic disc growth

    Science.gov (United States)

    Aumer, Michael; Binney, James; Schönrich, Ralph

    2016-04-01

    We perform a series of controlled N-body simulations of growing disc galaxies within non-growing, live dark matter haloes of varying mass and concentration. Our initial conditions include either a low-mass disc or a compact bulge. New stellar particles are continuously added on near-circular orbits to the existing disc, so spiral structure is continuously excited. To study the effect of combined spiral and giant molecular cloud (GMC) heating on the discs we introduce massive, short-lived particles that sample a GMC mass function. An isothermal gas component is introduced for a subset of the models. We perform a resolution study and vary parameters governing the GMC population, the histories of star formation and radial scale growth. Models with GMCs and standard values for the disc mass and halo density provide the right level of self-gravity to explain the age velocity dispersion relation of the Solar neighbourhood (Snhd). GMC heating generates remarkably exponential vertical profiles with scaleheights that are radially constant and agree with observations of galactic thin discs. GMCs are also capable of significantly delaying bar formation. The amount of spiral induced radial migration agrees with what is required for the metallicity distribution of the Snhd. However, in our standard models the outward migrating populations are not hot enough vertically to create thick discs. Thick discs can form in models with high baryon fractions, but the corresponding bars are too long, the young stellar populations too hot and the discs flare considerably.

  19. Computed tomography in lumbar herniated disc

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Chul Soon; Chang, Kee Hyun; Han, Man Chung [Seoul National University College of Medicine, Seoul (Korea, Republic of)

    1984-09-15

    197 spine CTs were performed from 29th , March 1982 to 7th March, 1984. Among them, 39 patients preoperatively diagnosed as herniated nucleus pulposus or bulging disc with CT and myelography were operated. 43 disc spaces of disc disease are analysed in true positive and false negative cases. Finally the accuracy, sensitivity and specificity of spine CT and myelography are calculated. The results are as follows: 1. The CT findings of disc diseases are in order of frequency, asymmetrical obliteration of epidural fat (82%) , ventral indentation or compression on dural sac (72%), focal protrusion of disc (64%), root changes - obliteration, displacement, compression, non-filling of metrizamide - (54%), diffuse disc bulging (36%), disc at body level (31%), disc calcifications (26%), disc vacuum (10%) and other associated findings - spinal stenosis, foraminal stenosis, ligament flavum thickening, facet joint hypertrophy (26%). 2. Sensitivities of spine CT and myelography are 95% and 94%, specificities are 67%, 50% and overall accuracies 93%, 87%, respectively. 3. Therefore, it is recommended that the spine CT be used as a primary diagnostic method and the myelography as a secondary complementary study when the CT gives no conclusive findings.

  20. Accretion Discs Show Their True Colours

    Science.gov (United States)

    2008-07-01

    Quasars are the brilliant cores of remote galaxies, at the hearts of which lie supermassive black holes that can generate enough power to outshine the Sun a trillion times. These mighty power sources are fuelled by interstellar gas, thought to be sucked into the hole from a surrounding 'accretion disc'. A paper in this week's issue of the journal Nature, partly based on observations collected with ESO's Very Large Telescope, verifies a long-standing prediction about the intensely luminous radiation emitted by these accretion discs. Uncovering the disc ESO PR Photo 21/08 Uncovering the inner disc "Astronomers were puzzled by the fact that the best models of these discs couldn't quite be reconciled with some of the observations, in particular, with the fact that these discs did not appear as blue as they should be," explains lead-author Makoto Kishimoto. Such a discrepancy could be the signal that there was something very wrong with the models. With his colleagues, he investigated this discrepancy by studying the polarised light from six quasars. This enabled them to demonstrate that the disc spectrum is as blue as predicted. "The crucial observational difficulty here has been that the disc is surrounded by a much larger torus containing hot dust, whose light partly outshines that of the disc," says Kishimoto. "Because the light coming from the disc is scattered in the disc vicinity and thus polarised, by observing only polarised light from the quasars, one can uncover the buried light from the disc." In a similar way that a fisherman would wear polarised sunglasses to help get rid of the glare from the water surface and allow him to see more clearly under the water, the filter on the telescope allowed the astronomers to see beyond surrounding clouds of dust and gas to the blue colour of the disc in infrared light. The observations were done with the FORS and ISAAC instruments on one of the 8.2-m Unit Telescopes of ESO's Very Large Telescope, located in the Atacama

  1. Neurexin-Neuroligin Synaptic Complex Regulates Schizophrenia-Related DISC1/Kal-7/Rac1 “Signalosome”

    DEFF Research Database (Denmark)

    Jacobsen, Sylwia Owczarek; Bang, Marie Louise; Berezin, Vladimir

    2015-01-01

    -attached intracellular domain in an activity-dependent manner, generating the soluble ectodomain of NX or NL. Expression of the NX1 and NX3 genes in the brain appears to be regulated by a schizophrenia-related protein, DISC1. Here, we show that soluble ecto-NX1β can regulate the expression of DISC1 and induce signaling...... downstream of DISC1. We also show that NL1 binds to a well-characterized DISC1 interaction partner, Kal-7, and this interaction can be compromised by DISC1. Our results indicate that the NX/NL synaptic complex is intrinsically involved in the regulation of DISC1 function, thus contributing to a better...

  2. Prediction of the correct measured activity of {sup 186}Re and {sup 188}Re from reactor produced natural rhenium using an artificial neural network

    Energy Technology Data Exchange (ETDEWEB)

    Leila Moghaddam, B., E-mail: lmoghaddam@aut.ac.i [Faculty of Nuclear Engineering and Physics, Amirkabir Technical University (Tehran Polytechnic), Hafez Street, Tehran (Iran, Islamic Republic of); Setayeshi, Saeed; Maragheh, Mohammad G.; Gholipour, Reza [Faculty of Nuclear Engineering and Physics, Amirkabir Technical University (Tehran Polytechnic), Hafez Street, Tehran (Iran, Islamic Republic of)

    2009-11-15

    To optimize the cost effectiveness of {sup 186}Re and {sup 188}Re production, which have recently been used as radio pharmaceuticals for therapeutic purposes, we designed an artificial neural network (ANN) to evaluate the activity of combined {sup 186}Re + {sup 188}Re. One of the production ways is the (n,gamma) reaction of natural rhenium which leads to combined {sup 186}Re + {sup 188}Re. Using the counted activity of {sup 186}Re + {sup 188}Re mixtures by a well type isotope calibrator, the precise activity of {sup 186}Re and {sup 188}Re is obtained by the ANN. A back-propagation ANN was trained using 30 activities of mixed {sup 186}Re + {sup 188}Re. The performance of the ANN was tested by Early-Stopping validation method, and the ANN was optimized with respect to its architecture. The response of the ANN shows significant precision that may be used for medical application of {sup 186}Re + {sup 188}Re mixtures.

  3. Sonic hedgehog functions upstream of disrupted-in-schizophrenia 1 (disc1): implications for mental illness.

    Science.gov (United States)

    Boyd, Penelope J; Cunliffe, Vincent T; Roy, Sudipto; Wood, Jonathan D

    2015-01-01

    DISRUPTED-IN-SCHIZOPHRENIA (DISC1) has been one of the most intensively studied genetic risk factors for mental illness since it was discovered through positional mapping of a translocation breakpoint in a large Scottish family where a balanced chromosomal translocation was found to segregate with schizophrenia and affective disorders. While the evidence for it being central to disease pathogenesis in the original Scottish family is compelling, recent genome-wide association studies have not found evidence for common variants at the DISC1 locus being associated with schizophrenia in the wider population. It may therefore be the case that DISC1 provides an indication of biological pathways that are central to mental health issues and functional studies have shown that it functions in multiple signalling pathways. However, there is little information regarding factors that function upstream of DISC1 to regulate its expression and function. We herein demonstrate that Sonic hedgehog (Shh) signalling promotes expression of disc1 in the zebrafish brain. Expression of disc1 is lost in smoothened mutants that have a complete loss of Shh signal transduction, and elevated in patched mutants which have constitutive activation of Shh signalling. We previously demonstrated that disc1 knockdown has a dramatic effect on the specification of oligodendrocyte precursor cells (OPC) in the hindbrain and Shh signalling is known to be essential for the specification of these cells. We show that disc1 is prominently expressed in olig2-positive midline progenitor cells that are absent in smo mutants, while cyclopamine treatment blocks disc1 expression in these cells and mimics the effect of disc1 knock down on OPC specification. Various features of a number of psychiatric conditions could potentially arise through aberrant Hedgehog signalling. We therefore suggest that altered Shh signalling may be an important neurodevelopmental factor in the pathobiology of mental illness. PMID:26405049

  4. Sonic hedgehog functions upstream of disrupted-in-schizophrenia 1 (disc1: implications for mental illness

    Directory of Open Access Journals (Sweden)

    Penelope J. Boyd

    2015-10-01

    Full Text Available DISRUPTED-IN-SCHIZOPHRENIA (DISC1 has been one of the most intensively studied genetic risk factors for mental illness since it was discovered through positional mapping of a translocation breakpoint in a large Scottish family where a balanced chromosomal translocation was found to segregate with schizophrenia and affective disorders. While the evidence for it being central to disease pathogenesis in the original Scottish family is compelling, recent genome-wide association studies have not found evidence for common variants at the DISC1 locus being associated with schizophrenia in the wider population. It may therefore be the case that DISC1 provides an indication of biological pathways that are central to mental health issues and functional studies have shown that it functions in multiple signalling pathways. However, there is little information regarding factors that function upstream of DISC1 to regulate its expression and function. We herein demonstrate that Sonic hedgehog (Shh signalling promotes expression of disc1 in the zebrafish brain. Expression of disc1 is lost in smoothened mutants that have a complete loss of Shh signal transduction, and elevated in patched mutants which have constitutive activation of Shh signalling. We previously demonstrated that disc1 knockdown has a dramatic effect on the specification of oligodendrocyte precursor cells (OPC in the hindbrain and Shh signalling is known to be essential for the specification of these cells. We show that disc1 is prominently expressed in olig2-positive midline progenitor cells that are absent in smo mutants, while cyclopamine treatment blocks disc1 expression in these cells and mimics the effect of disc1 knock down on OPC specification. Various features of a number of psychiatric conditions could potentially arise through aberrant Hedgehog signalling. We therefore suggest that altered Shh signalling may be an important neurodevelopmental factor in the pathobiology of mental

  5. Evolution of linear warps in accretion discs and applications to protoplanetary discs in binaries

    CERN Document Server

    Foucart, Francois

    2014-01-01

    The existence of warped accretion discs is expected in a wide variety of astrophysical systems, including circumstellar discs in binaries and discs around binary protostars. A common feature of these discs is that they are perturbed by a misaligned external potential. In this paper, we study the long-term evolution of the disc warp and precession in the case of thick discs (with the dimensionless thickness $H/r$ larger than the viscosity parameter $\\alpha$) in which bending waves can propagate. For small warps, such discs undergo approximately rigid-body precession with a coherent global frequency. We derive the analytical expressions for the warp/twist profiles of the disc and the alignment timescale for a variety of disc models/parameters. Applying our results to circumbinary discs, we find that these discs align with the orbital plane of the binary on a timescale comparable to the global precession time of the disc, and typically much smaller than its viscous timescale. The development of parametric instab...

  6. The case for cases B and C: intrinsic hydrogen line ratios of the broad-line region of active galactic nuclei, reddenings, and accretion disc sizes

    CERN Document Server

    Gaskell, C Martin

    2016-01-01

    Low-redshift active galactic nuclei (AGNs) with extremely blue optical spectral indices are shown to have a mean, velocity-averaged, broad-line H$\\alpha$/H$\\beta$ ratio of $\\thickapprox 2.72 \\pm 0.04$, consistent with the Baker-Menzel Case B value. Comparison of a wide range of properties of the very bluest AGNs with those of a luminosity-matched subset of the Dong et al. blue AGN sample indicates that the only difference is the internal reddening. Ultraviolet fluxes are brighter for the bluest AGNs by an amount consistent with the flat AGN reddening curve of Gaskell et al. (2004). The lack of a significant difference in the GALEX (FUV--NUV) colour index strongly rules out a steep SMC-like reddening curve and also argues against an intrinsically harder spectrum. For very blue AGNs the Ly$\\alpha$/H$\\beta$ ratio is also consistent with being the Case B value. The Case B ratios provide strong support for the self-shielded broad-line model of Gaskell, Klimek & Nazarova. It is proposed that the greatly enhance...

  7. Disc degeneration and chronic low back pain: an association which becomes nonsignificant when endplate changes and disc contour are taken into account

    International Nuclear Information System (INIS)

    The objective of this study was to assess the association between severe disc degeneration (DD) and low back pain (LBP). A case-control study was conducted with 304 subjects, aged 35-50, recruited in routine clinical practice across six hospitals; 240 cases (chronic LBP patients with a median pain duration of 46 months) and 64 controls (asymptomatic subjects without any lifetime history of significant LBP). The following variables were assessed once, using previously validated methods: gender, age, body mass index (BMI), lifetime smoking exposure, degree of physical activity, severity of LBP, disability, and findings on magnetic resonance (MRI) (disc degeneration, Modic changes (MC), disc protrusion/hernia, annular tears, spinal stenosis, and spondylolisthesis). Radiologists who interpreted MRI were blinded to the subjects' characteristics. A multivariate logistic regression model assessed the association between severe DD and chronic LBP, adjusting for gender, age, BMI, physical activity, MC, disc protrusion/hernia, and spinal stenosis. Severe DD at ≥1 level was found in 46.9 % of the controls and 65.8 % of the cases. Crude odds ratio (95 % CI), for suffering chronic LBP when having severe DD, was 2.06 (1.05; 4.06). After adjusting for ''MC'' and ''disc protrusion/hernia,'' it was 1.81 (0.81; 4.05). The association between severe DD and LBP ceases to be significant when adjusted for MC and disc protrusion/hernia. These results do not support that DD as a major cause of chronic LBP. (orig.)

  8. Pharmacological mydriasis and optic disc examination

    Science.gov (United States)

    Kirwan, J.; Gouws, P.; Linnell, A.; Crowston, J.; Bunce, C.

    2000-01-01

    AIM—To determine whether pharmacological mydriasis leads to a significant difference in interobserver agreement of optic disc measurement compared with examination without mydriasis.
METHOD—A cross sectional study was performed with a pair of observers examining the optic disc of two randomised groups of patients, one group before diagnostic mydriasis, and the other afterwards. Horizontal and vertical disc diameters and cup/disc ratios were measured with a 78 dioptre lens. The study was repeated with another observer pair and two further groups of patients.
RESULTS—In study A 86 subjects were examined in total (52 without and 34 with mydriasis). In study B 87 subjects were examined (45 without and 42 with mydriasis). The 95% limits of agreement of the cup/disc ratio measurement differences were significantly larger without mydriasis (p<0.001 for all studies (F test)). For both studies examination after mydriasis gave significantly greater agreement for vertical and horizontal cup/disc ratios. The cases with good agreement (0.1 difference or better) for vertical cup/disc ratios were 37/52 (72%) and 34 /45 (76%) without mydriasis and 33/34 (97%) and 40/42 (95%) respectively with mydriasis. Similar differences were recorded for horizontal cup/disc ratios. Disc diameter measurement results showed similar differences in study A but were not affected by mydriasis in study B.
CONCLUSIONS—Examination of the optic disc without pharmacological mydriasis gives significantly poorer interobserver agreement. In this study, the mean 95% limits of agreement values for all cup/disc ratio values were 0.27 for examination without mydriasis and 0.13 for examination with mydriasis. A measure outside these limits would suggest a real difference. This study indicates that mydriasis is important for reproducible clinical examination in glaucoma.

 PMID:10906099

  9. Intraosseous disc prolapse: A diagnostic puzzle

    Directory of Open Access Journals (Sweden)

    Parasnis Rajesh

    2006-01-01

    Full Text Available Background : Schmorl′s node or intraosseous disc prolapse is herniation of the nucleus pulposus material through the vertebral end plates. Presence of Schmorl′s nodes as end plate lesions following trauma, tumours and osteoporosis further complicates diagnosis. The present study was done to understand diagnosis and approach to management of symptomatic Schmorl′s nodes. Methods : During a period of three years we came across 14 patients who presented with severe back pain. Conventional radiographs, CT Scans and MRI showed the presence of end plate lesions with varied radiological appearance. The first group, comprising of seven patients had lytic lesions without any sclerosis on only one side of the intervertebral disc as seen on the CT scan. The second group comprising of five patients had sclerotic lesions with new bone formation associated with disc space reduction. The two patients in the third group showed a combined lytic and sclerotic lesion without any soft tissue changes. MRI of eleven patients revealed hypointense lesion on T 1 and T 2 weighted images with surrounding zone of hyper intensity on T 2 weighted images. The remaining three patients, did not have this hyper intense zone on T 2 weighted images . In five patients multiple Schmorl′s nodes were observed. Diagnosis of symptomatic Schmorl′s nodes was mainly done by exclusion. All patients were given rest and anti-inflammatory drugs followed by exercises. Results : The first two groups of patients responded to the treatment and had complete relief of symptoms but both the patients in third group had persistent symptoms. MRI repeated after eight weeks showed an enhancing lesion with prevertebral soft tissue. A transpedicular core biopsy proved the lesion to be tuberculosis in one patient. Anti Koch′s therapy was promptly started and follow up study showed resolution of the lesions. At the end of the study period all the patients were asymptomatic and returned to their

  10. Electronic and thermal lensing in diode end-pumped Yb:YAG laser rods and discs

    International Nuclear Information System (INIS)

    The lensing effects in diode end-pumped Yb:YAG laser rods and discs are studied. Two mechanisms of refractive-index changes are taken into account, thermal and electronic (due to the difference between the excited- and ground-state Yb3+ polarisabilities), as well as pump-induced deformation of the laser crystal. Under pulsed pumping, the electronic lensing effect prevails over the thermal one in both rods and discs. In rods pumped by a highly focused cw beam, the dioptric power of the electronic lens exceeds that of the thermal lens, whereas in discs steady-state lensing is predominantly due to the thermal mechanism. (active media)

  11. Unusual disc herniation in a dog: a case history report

    International Nuclear Information System (INIS)

    Unusual disc herniation was identified in a dog. Disc herniation was considered unusual because of its displacement into the vertebral endplate of the adjoining vertebra. Unusual disc herniation in this dog was compared with Schmorl's node in humans

  12. Changes in disc herniation after CT-guided Percutaneous Laser Disc Decompression (PLDD): MR findings

    Science.gov (United States)

    Brat, Hugues G.; Bouziane, Tarik; Lambert, Jean; Divano, Luisa

    2004-09-01

    The aim of Percutaneous Laser Disc Decompression (PLDD) is to vaporize a small portion of the nucleus pulposus. Clinical efficacy of this technique is largely proven. However, time-evolution of intervertebral disc and its hernia after PLDD is not known. This study analyses changes in disc herniation and its native intervertebral disc at a mean follow-up of 7.5 months after PLDD in asymptomatic patients. Main observations at MRI are appearance of a high signal on T2WI in the hernia in 59%, shrinking of the hernia in 66% and overall stability of disc height.

  13. A direct protein kinase B-targeted anti inflammatory activity of cordycepin from artificially cultured fruit body of Cordyceps militaris

    Directory of Open Access Journals (Sweden)

    Ju Young Yoon

    2015-01-01

    Full Text Available Background: Cordyceps militaris is one of well-known medicinal mushrooms with anti-inflammatory, anti-cancer, anti-diabetic, and anti-obesity activities. Objective: The objective of the following study is to isolate chemical components from the ethanol extract (Cm-EE from Cordyceps militaris and to evaluate their anti-inflammatory activities. Materials and Methods: Column chromatographic separation was performed and anti-inflammatory roles of these compounds were also examined by using NO production and protein kinase B (AKT activity assays. Results: From Cm-EE, 13 constituents, including trehalose (1, cordycepin (2, 6-hydroxyethyladenosine (3, nicotinic amide (4, butyric acid (5, β-dimorphecolic acid (6, α-dimorphecolic acid (7, palmitic acid (8, linoleic acid (9, cordycepeptide A (10, 4-(2-hydroxy-3-((9E,12E-octadeca-9,12-dienoyloxypropoxy-2-(trimethylammoniobutanoate (11, 4-(2-hydroxy-3-(palmitoyloxypropoxy-2-(trimethylammoniobutanoate (12, and linoleic acid methyl ester (13 were isolated. Of these components, compound 2 displayed a significant inhibitory effect on NO production in lipopolysaccharide (LPS-activated RAW264.7 cells. Furthermore, this compound strongly and directly suppressed the kinase activity of AKT, an essential signalling enzyme in LPS-induced NO production, by interacting with its ATP binding site. Conclusion: C. militaris could have anti-inflammatory activity mediated by cordycepin-induced suppression of AKT.

  14. Thin, thick and dark discs in LCDM

    CERN Document Server

    Read, J I; Agertz, O; Debattista, Victor P

    2008-01-01

    In a LCDM cosmology, the Milky Way accretes satellites into the stellar disc. We use cosmological simulations to assess the frequency of near disc plane and higher inclination accretion events, and collisionless simulations of satellite mergers to quantify the final state of the accreted material and the effect on the thin disc. On average, a Milky Way-sized galaxy has 1.5 subhalos with vmax>80km/s; 5 with vmax>60km/s; and 13 with vmax>40km/s merge at redshift z>1. A third of these merge at an impact angle 20 degrees) are twice as likely as low inclination ones. These lead to structures that closely resemble the recently discovered inner/outer stellar halos. They also do more damage to the Milky Way stellar disc creating a more pronounced flare, and warp; both long-lived and consistent with current observations. The most massive mergers (vmax > 80km/s) heat t he thin disc enough to produce a thick disc. These heated thin disc stars are essential for obtaining a thick disc as massive as that seen in the Milky ...

  15. Modeling quasar accretion disc temperature profiles

    CERN Document Server

    Hall, Patrick B; Chajet, L S; Weiss, E; Nixon, C J

    2013-01-01

    Microlensing observations indicate that quasar accretion discs have half-light radii larger than expected from standard theoretical predictions based on quasar fluxes or black hole masses. Blackburne and colleagues have also found a very weak wavelength dependence of these half-light radii. We consider disc temperature profile models that might match these observations. Nixon and colleagues have suggested that misaligned accretion discs around spinning black holes will be disrupted at radii small enough for the Lense-Thirring torque to overcome the disc's viscous torque. Gas in precessing annuli torn off a disc will spread radially and intersect with the remaining disc, heating the disc at potentially large radii. However, if the intersection occurs at an angle of more than a degree or so, highly supersonic collisions will shock-heat the gas to a Compton temperature of T~10^7 K, and the spectral energy distributions (SEDs) of discs with such shock-heated regions are poor fits to observations of quasar SEDs. T...

  16. Genetic association studies in lumbar disc degeneration

    DEFF Research Database (Denmark)

    Eskola, Pasi J; Lemmelä, Susanna; Kjær, Per;

    2012-01-01

    Low back pain is associated with lumbar disc degeneration, which is mainly due to genetic predisposition. The objective of this study was to perform a systematic review to evaluate genetic association studies in lumbar disc degeneration as defined on magnetic resonance imaging (MRI) in humans....

  17. Cervical disc hernia operations through posterior laminoforaminotomy

    OpenAIRE

    Coskun Yolas; Nuriye Guzin Ozdemir; Hilmi Onder Okay; Ayhan Kanat; Mehmet Senol; Ibrahim Burak Atci; Hakan Yilmaz; Mustafa Kemal Coban; Mehmet Onur Yuksel; Umit Kahraman

    2016-01-01

    Objective: The most common used technique for posterolateral cervical disc herniations is anterior approach. However, posterior cervical laminotoforaminomy can provide excellent results in appropriately selected patients with foraminal stenosis in either soft disc prolapse or cervical spondylosis. The purpose of this study was to present the clinical outcomes following posterior laminoforaminotomy in patients with radiculopathy. Materials and Methods: We retrospectively evaluated 35 patients ...

  18. Forbidden calcium lines as disc tracers

    CERN Document Server

    Aret, Anna

    2015-01-01

    Forbidden emission lines are particularly valuable disc tracers, because their profiles reflect the kinematics within their formation region. Here we present a short excerpt from the results of a spectroscopic survey of evolved massive stars surrounded by high-density discs.

  19. Computing Decoupled Residuals for Compact Disc Players

    DEFF Research Database (Denmark)

    Odgaard, Peter Fogh; Stoustrup, Jakob; Andersen, Palle;

    2006-01-01

    pair of residuals generated by Compact Disc Player. However, these residuals depend on the performance of position servos in the Compact Disc Player. In other publications of the same authors a pair of decoupled residuals is derived. However, the computation of these alternative residuals has been...

  20. Simulations of the Galactic Centre Stellar Discs In a Warped Disc Origin Scenario

    International Nuclear Information System (INIS)

    The Galactic Center (GC) hosts a population of young stars some of which seem to form a system of mutually inclined warped discs. While the presence of young stars in the close vicinity of the massive black hole is already problematic, their orbital configuration makes the situation even more puzzling. We present a possible warped disc origin scenario for these stars, which assumes an initially flat accretion disc which develops a warp through Pringle instability, or Bardeen-Petterson Effect. By working out the critical radii and the time scales involved, we argue that disc warping is plausible for GC parameters. We construct time evolution models for such discs considering the discs' self-gravity, and the torques exerted by the surrounding old star cluster. Our simulations suggest that the best agreement for a purely self-gravitating model is obtained for a disc-to-black hole mass ratio of Md/Mbh ∼ 0.001.

  1. Simulations of the Galactic Centre Stellar Discs In a Warped Disc Origin Scenario

    Science.gov (United States)

    Ulubay-Siddiki, A.; Bartko, H.

    2012-07-01

    The Galactic Center (GC) hosts a population of young stars some of which seem to form a system of mutually inclined warped discs. While the presence of young stars in the close vicinity of the massive black hole is already problematic, their orbital configuration makes the situation even more puzzling. We present a possible warped disc origin scenario for these stars, which assumes an initially flat accretion disc which develops a warp through Pringle instability, or Bardeen-Petterson Effect. By working out the critical radii and the time scales involved, we argue that disc warping is plausible for GC parameters. We construct time evolution models for such discs considering the discs' self-gravity, and the torques exerted by the surrounding old star cluster. Our simulations suggest that the best agreement for a purely self-gravitating model is obtained for a disc-to-black hole mass ratio of Md/Mbh ~ 0.001.

  2. Strongly magnetized accretion discs require poloidal flux

    Science.gov (United States)

    Salvesen, Greg; Armitage, Philip J.; Simon, Jacob B.; Begelman, Mitchell C.

    2016-05-01

    Motivated by indirect observational evidence for strongly magnetized accretion discs around black holes, and the novel theoretical properties of such solutions, we investigate how a strong magnetization state can develop and persist. To this end, we perform local simulations of accretion discs with an initially purely toroidal magnetic field of equipartition strength. We demonstrate that discs with zero net vertical magnetic flux and realistic boundary conditions cannot sustain a strong toroidal field. However, a magnetic pressure-dominated disc can form from an initial configuration with a sufficient amount of net vertical flux and realistic boundary conditions. Our results suggest that poloidal flux is a necessary prerequisite for the sustainability of strongly magnetized accretion discs.

  3. Propeller outflows from an MRI disc

    CERN Document Server

    Lii, Patrick S; Ustyugova, Galina V; Koldoba, Alexander V; Lovelace, Richard V E

    2013-01-01

    We present the results of axisymmetric simulations of MRI-driven accretion onto a rapidly rotating, magnetized star accreting in the propeller regime. The stellar magnetosphere corotates with the star, forming a centrifugal barrier at the disc-magnetosphere boundary which inhibits matter accretion onto the star. Instead, the disc matter accumulates at the disc-magnetosphere interface and slowly diffuses into the inner magnetosphere where it picks up angular momentum and is quickly ejected from the system as an outflow. Due to the interaction of the matter with the magnetosphere, this wind is discontinuous and is launched as discrete plasmoids. If the ejection rate is lower than the disc accretion rate, the matter accumulates at the disc-magnetosphere boundary faster than it can be ejected. In this case, accretion onto the star proceeds through the episodic accretion instability in which episodes of matter accumulation are followed by simultaneous accretion and ejection. During the accretion phase of this inst...

  4. Magnetic resonance imaging of intervertebral disc degeneration

    Energy Technology Data Exchange (ETDEWEB)

    Maeda, Hiroshi; Noguchi, Masao (Kitakyushu City Yahata Hospital, Fukuoka (Japan)); Kira, Hideaki; Fujiki, Hiroshi; Shimokawa, Isao; Hinoue, Kaichi

    1993-02-01

    The aim of this study was to correlate the degree of lumbar intervertebral disc degeneration with findings of magnetic resonance imaging (MRI). Seventeen autopsied (from 7 patients) and 21 surgical (from 20 patients) intervertebral discs were used as specimens for histopathological examination. In addition, 21 intervertebral discs were examined on T2-weighted images. Histopathological findings from both autopsied and surgical specimens were well correlated with MRI findings. In particular, T2-weighted images reflected increased collagen fibers and rupture within the fibrous ring accurately. However, when severely degenerated intervertebral discs and hernia protruding the posterior longitudinal ligament existed, histological findings were not concordant well with T2-weighted images. Morphological appearances of autopsy specimens, divided into four on T2-weighted images, were well consistent with histological degeneration. This morphological classification, as shown on T2-weighted images, could also be used in the evaluation of intervertebral disc degeneration. (N.K.).

  5. The formation of planets by disc fragmentation

    Directory of Open Access Journals (Sweden)

    Stamatellos Dimitris

    2013-04-01

    Full Text Available I discuss the role that disc fragmentation plays in the formation of gas giant and terrestrial planets, and how this relates to the formation of brown dwarfs and low-mass stars, and ultimately to the process of star formation. Protostellar discs may fragment, if they are massive enough and can cool fast enough, but most of the objects that form by fragmentation are brown dwarfs. It may be possible that planets also form, if the mass growth of a proto-fragment is stopped (e.g. if this fragment is ejected from the disc, or suppressed and even reversed (e.g by tidal stripping. I will discuss if it is possible to distinguish whether a planet has formed by disc fragmentation or core accretion, and mention of a few examples of observed exoplanets that are suggestive of formation by disc fragmentation.

  6. Lumbar Epidural Varix Mimicking Disc Herniation.

    Science.gov (United States)

    Bursalı, Adem; Akyoldas, Goktug; Guvenal, Ahmet Burak; Yaman, Onur

    2016-07-01

    Lumbar radiculopathy is generally caused by such well-recognized entity as lumbar disc herniation in neurosurgical practice; however rare pathologies such as thrombosed epidural varix may mimic them by causing radicular symptoms. In this case report, we present a 26-year-old man with the complaint of back and right leg pain who was operated for right L4-5 disc herniation. The lesion interpreted as an extruded disc herniation preoperatively was found to be a thrombosed epidural varix compressing the nerve root preoperatively. The nerve root was decompressed by shrinking the lesion with bipolar thermocoagulation and excision. The patient's complaints disappeared in the postoperative period. Thrombosed lumbar epidural varices may mimic lumbar disc herniations both radiologically and clinically. Therefore, must be kept in mind in the differential diagnosis of lumbar disc herniations. Microsurgical techniques are mandatory for the treatment of these pathologies and decompression with thermocoagulation and excision is an efficient method. PMID:27446525

  7. Strongly magnetized accretion discs require poloidal flux

    CERN Document Server

    Salvesen, Greg; Simon, Jacob B; Begelman, Mitchell C

    2016-01-01

    Motivated by indirect observational evidence for strongly magnetized accretion discs around black holes, and the novel theoretical properties of such solutions, we investigate how a strong magnetization state can develop and persist. To this end, we perform local simulations of accretion discs with an initially purely toroidal magnetic field of equipartition strength. We demonstrate that discs with zero net vertical magnetic flux and realistic boundary conditions cannot sustain a strong toroidal field. However, a magnetic pressure-dominated disc can form from an initial configuration with a sufficient amount of net vertical flux and realistic boundary conditions. Our results suggest that poloidal flux is a necessary prerequisite for the sustainability of strongly magnetized accretion discs.

  8. Lumbar disc cyst with contralateral radiculopathy

    Directory of Open Access Journals (Sweden)

    Kishore Tourani

    2012-08-01

    Full Text Available Disc cysts are uncommon intraspinal cystic lesions located in the ventrolateral epidural space. They communicate with the nucleus pulposus of the intervertebral disc and cause symptoms by radicular compression. We report a unique case of lumbar disc cyst that was associated with disc herniation and contralateral radiculopathy. A 22 year old male presented with one month history of back-ache radiating to the left leg. Magnetic Resonance Imaging (MRI showed L3-L4 disc herniation with annular tear and cystic lesion in the extradural space anterior to the thecal sac on right side, which increased in size over a period of 3 weeks. L3 laminectomy and bilateral discectomy and cyst excision was done with partial improvement of patients symptoms.

  9. Lumbar Epidural Varix Mimicking Disc Herniation

    Science.gov (United States)

    Bursalı, Adem; Guvenal, Ahmet Burak; Yaman, Onur

    2016-01-01

    Lumbar radiculopathy is generally caused by such well-recognized entity as lumbar disc herniation in neurosurgical practice; however rare pathologies such as thrombosed epidural varix may mimic them by causing radicular symptoms. In this case report, we present a 26-year-old man with the complaint of back and right leg pain who was operated for right L4–5 disc herniation. The lesion interpreted as an extruded disc herniation preoperatively was found to be a thrombosed epidural varix compressing the nerve root preoperatively. The nerve root was decompressed by shrinking the lesion with bipolar thermocoagulation and excision. The patient's complaints disappeared in the postoperative period. Thrombosed lumbar epidural varices may mimic lumbar disc herniations both radiologically and clinically. Therefore, must be kept in mind in the differential diagnosis of lumbar disc herniations. Microsurgical techniques are mandatory for the treatment of these pathologies and decompression with thermocoagulation and excision is an efficient method. PMID:27446525

  10. Strongly magnetized accretion discs require poloidal flux

    Science.gov (United States)

    Salvesen, Greg; Armitage, Philip J.; Simon, Jacob B.; Begelman, Mitchell C.

    2016-08-01

    Motivated by indirect observational evidence for strongly magnetized accretion discs around black holes, and the novel theoretical properties of such solutions, we investigate how a strong magnetization state can develop and persist. To this end, we perform local simulations of accretion discs with an initially purely toroidal magnetic field of equipartition strength. We demonstrate that discs with zero net vertical magnetic flux and realistic boundary conditions cannot sustain a strong toroidal field. However, a magnetic pressure-dominated disc can form from an initial configuration with a sufficient amount of net vertical flux and realistic boundary conditions. Our results suggest that poloidal flux is a necessary prerequisite for the sustainability of strongly magnetized accretion discs.

  11. Magnetic resonance imaging of intervertebral disc degeneration

    International Nuclear Information System (INIS)

    The aim of this study was to correlate the degree of lumbar intervertebral disc degeneration with findings of magnetic resonance imaging (MRI). Seventeen autopsied (from 7 patients) and 21 surgical (from 20 patients) intervertebral discs were used as specimens for histopathological examination. In addition, 21 intervertebral discs were examined on T2-weighted images. Histopathological findings from both autopsied and surgical specimens were well correlated with MRI findings. In particular, T2-weighted images reflected increased collagen fibers and rupture within the fibrous ring accurately. However, when severely degenerated intervertebral discs and hernia protruding the posterior longitudinal ligament existed, histological findings were not concordant well with T2-weighted images. Morphological appearances of autopsy specimens, divided into four on T2-weighted images, were well consistent with histological degeneration. This morphological classification, as shown on T2-weighted images, could also be used in the evaluation of intervertebral disc degeneration. (N.K.)

  12. Spine imaging after lumbar disc replacement: pitfalls and current recommendations

    Directory of Open Access Journals (Sweden)

    Sandén Bengt

    2009-07-01

    Full Text Available Abstract Background Most lumbar artificial discs are still composed of stainless steel alloys, which prevents adequate postoperative diagnostic imaging of the operated region when using magnetic resonance imaging (MRI. Thus patients with postoperative radicular symptoms or claudication after stainless steel implants often require alternative diagnostic procedures. Methods Possible complications of lumbar total disc replacement (TDR are reviewed from the available literature and imaging recommendations given with regard to implant type. Two illustrative cases are presented in figures. Results Access-related complications, infections, implant wear, loosening or fracture, polyethylene inlay dislodgement, facet joint hypertrophy, central stenosis, and ankylosis of the operated segment can be visualised both in titanium and stainless steel implants, but require different imaging modalities due to magnetic artifacts in MRI. Conclusion Alternative radiographic procedures should be considered when evaluating patients following TDR. Postoperative complications following lumbar TDR including spinal stenosis causing radiculopathy and implant loosening can be visualised by myelography and radionucleotide techniques as an adjunct to plain film radiographs. Even in the presence of massive stainless steel TDR implants lumbar radicular stenosis and implant loosening can be visualised if myelography and radionuclide techniques are applied.

  13. Comparison of ultrasonic with stirrer performance for removal of sunset yellow (SY) by activated carbon prepared from wood of orange tree: artificial neural network modeling.

    Science.gov (United States)

    Ghaedi, A M; Ghaedi, M; Karami, P

    2015-03-01

    The present work focused on the removal of sunset yellow (SY) dye from aqueous solution by ultrasound-assisted adsorption and stirrer by activated carbon prepared from wood of an orange tree. Also, the artificial neural network (ANN) model was used for predicting removal (%) of SY dye based on experimental data. In this study a green approach was described for the synthesis of activated carbon prepared from wood of an orange tree and usability of it for the removal of sunset yellow. This material was characterized using scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The impact of variables, including initial dye concentration (mg/L), pH, adsorbent dosage (g), sonication time (min) and temperature (°C) on SY removal were studied. Fitting the experimental equilibrium data of different isotherm models such as Langmuir, Freundlich, Temkin and Dubinin-Radushkevich models display the suitability and applicability of the Langmuir model. Analysis of experimental adsorption data by different kinetic models including pseudo-first and second order, Elovich and intraparticle diffusion models indicate the applicability of the second-order equation model. The adsorbent (0.5g) is applicable for successful removal of SY (>98%) in short time (10min) under ultrasound condition. PMID:25435487

  14. Modified high-density lipoproteins by artificial sweetener, aspartame, and saccharin, showed loss of anti-atherosclerotic activity and toxicity in zebrafish.

    Science.gov (United States)

    Kim, Jae-Yong; Park, Ki-Hoon; Kim, Jihoe; Choi, Inho; Cho, Kyung-Hyun

    2015-01-01

    Safety concerns have been raised regarding the association of chronic consumption of artificial sweeteners (ASs) with metabolic disorders, especially in the heart and brain. There has been no information on the in vivo physiological effects of AS consumption in lipoprotein metabolism. High-dosage treatment (final 25, 50, and 100 mM) with AS (aspartame, acesulfame K, and saccharin) to human high-density lipoprotein (HDL) induced loss of antioxidant ability along with elevated atherogenic effects. Aspartame-treated HDL3 (final 100 mM) almost all disappeared due to putative proteolytic degradation. Aspartame- and saccharin-treated HDL3 showed more enhanced cholesteryl ester transfer activity, while their antioxidant ability was disappeared. Microinjection of the modified HDL3 exacerbated the inflammatory death in zebrafish embryos in the presence of oxLDL. These results show that AS treatment impaired the beneficial functions of HDL, resulting in loss of antioxidant and anti-atherogenic activities. These results suggest that aspartame and saccharin could be toxic to the human circulation system as well as embryonic development via impairment of lipoprotein function. PMID:25142179

  15. Application of Artificial Neural Network (ANN in Estimation of Body Mass Index (BMI Based on the Connection Between Environmental Factors and Physical Activity

    Directory of Open Access Journals (Sweden)

    Seyed Hosein Hoseini

    2012-08-01

    Full Text Available One of the main concerns of people in modern societies is increasing the Body Mass Index (BMI level.BMI, in fact, can be considered as an indicator of overall health condition. Genetic aspects aside, the BMIlevel is affected by different factors, such as socio-economic, environmental, and physical activity level.This study investigated the effect of different factors on the BMI level of a sample population of 470 adultsof three residential neighbourhoods in Shiraz, Iran. The Pearson correlation test, independent sample Ttest and One Way ANOVA were used to extract the variables which significantly influenced the BMI. Thestatistical analysis showed that despite the apparent association of BMI with physical activity level, it isinfluenced by several factors such as age, residence record, number of children, distance to bus or taxistop, indoor or sport exercise. Then, an Artificial Neural Network (ANN was applied to predict the level ofpersonal BMI. The results of this analysis showed that the generalized estimating ANN model wassatisfactory in estimating the BMI based on the introduced pattern

  16. Application of Artificial Neural Network (ANN in Estimation of Body Mass Index (BMI Based on the Connection Between Environmental Factors and Physical Activity

    Directory of Open Access Journals (Sweden)

    Seyed Hosein Hoseini

    2012-07-01

    Full Text Available One of the main concerns of people in modern societies is increasing the Body Mass Index (BMI level. BMI, in fact, can be considered as an indicator of overall health condition. Genetic aspects aside, the BMI level is affected by different factors, such as socio-economic, environmental, and physical activity level. This study investigated the effect of different factors on the BMI level of a sample population of 470 adults of three residential neighbourhoods in Shiraz, Iran. The Pearson correlation test, independent sample Ttest and One Way ANOVA were used to extract the variables which significantly influenced the BMI. The statistical analysis showed that despite the apparent association of BMI with physical activity level, it is influenced by several factors such as age, residence record, number of children, distance to bus or taxi stop, indoor or sport exercise. Then, an Artificial Neural Network (ANN was applied to predict the level of personal BMI. The results of this analysis showed that the generalized estimating ANN model was satisfactory in estimating the BMI based on the introduced pattern.

  17. Artificial Video for Video Analysis

    Science.gov (United States)

    Gallis, Michael R.

    2010-01-01

    This paper discusses the use of video analysis software and computer-generated animations for student activities. The use of artificial video affords the opportunity for students to study phenomena for which a real video may not be easy or even possible to procure, using analysis software with which the students are already familiar. We will…

  18. Pre-Fukushima levels of artificial radionuclides activities in maritime samples from King George Island (South Shetlands, Antarctica)

    Energy Technology Data Exchange (ETDEWEB)

    Sobiech-Matura, K. [European Commision DG-JRC Institute for Reference Materials and Measurements, Retieseweg 111, Geel (Belgium); Institute of Botany, Zdzislaw Czeppe Department of Polar Research and Documentation, Jagiellonian University, Kopernika 27, Krakow (Poland); Mietelski, J.W. [The Henryk Niewodniczanski Institute of Nuclear Physics, Polish Academy of Sciences, W.E. Radzikowskiego 152, Krakow (Poland); Olech, M.A. [Institute of Botany, Zdzislaw Czeppe Department of Polar Research and Documentation, Jagiellonian University, Kopernika 27, Krakow (Poland); Department of Antarctic Biology, Polish Academy of Sciences, Ustrzycka 10/12, Warsaw (Poland)

    2014-07-01

    Different maritime samples were collected at King George Island during Polish scientific expeditions in years 2005/2006 and 2006/2007. They originated mainly from Admiralty Bay region. Activities of {sup 137}Cs, {sup 238,239+240}Pu, {sup 90}Sr and {sup 241}Am were measured using γ-, β- and α-spectrometry. Our measurements allow estimating the state of radioactive pollution of Antarctic environment directly before the Fukushima accident. Examined samples included different elements of Antarctic marine environment: macro-algae (e.g. Cystosphaera jacquinotii, Ascoseira mirabilis), fishes(e.g. Notothenia coriiceps, Chaenocephalus aceratus), birds (e.g. Pygoscelis adeliae, P. papua), and crustaceans (e.g. Euphausia superba, Waldeckia obesa). Activity concentrations of {sup 137}Cs vary from <0.3 to 21.8 ± 2.1 Bq/kg d.w. In comparison with results obtained for samples of animals and macro-algae previously [1,2] our results are similar or lower. Activity concentrations of {sup 239+240}Pu range from <0.2 to 455 ± 56 mBq/kg d.w. and comparing to previous results [1,2] they were similar or lower. For maritime animals from Terra Nova Bay [3] results are also similar or lower than obtained in present project. Activity concentrations of {sup 238}Pu in samples varied from <0.2 to 79 ± 22 mBq/kg d.w. In comparison to results presented in [1,2,3] our values are similar or higher. Activity concentrations obtained for {sup 90}Sr varied from <1.5 to 73 ± 24 Bq/kg d.w. and are similar or lower then values given in [2,3]. Activity concentrations of {sup 241}Am varied from <9.4 to 29.8 ± 9.3 mBq/kg d.w. and they are similar or higher than values obtained in [3] and similar to that from [1]. Obtained results show that levels of radioactive contamination were very low and in many cases lower than the detection limit. Planned further investigation will allow estimating the environmental condition after the Fukushima accident. (authors)

  19. Artificial Inteligence and Law

    OpenAIRE

    Fuková, Kateřina

    2012-01-01

    Submitted diploma work Artificial Intelligence and Law deals with the rule of law and its position in the process of new advanced technologies in computer cybernetics and further scientific disciplines related with artificial intelligence and its creation. The first part of the work introduces the history of the first imagines about artificial intelligence and concerns with its birth. This chapter presents main theoretical knowledge and hypotheses defined artificial intelligence and progre...

  20. Artificial Skin in Robotics

    OpenAIRE

    Strohmayr, Michael

    2012-01-01

    Artificial Skin - A comprehensive interface for system-environment interaction - This thesis investigates a multifunctional artificial skin as touch sensitive whole-body cover for robotic systems. To further the evolution from tactile sensors to an implementable artificial skin a general concept for the design process is derived. A standard test procedure is proposed to evaluate the performance. The artificial skin contributes to a safe and intuitive physical human robot interaction.

  1. Origin of the X-ray disc-reflection steep radial emissivity

    OpenAIRE

    Svoboda, Jiří; Dovčiak, Michal; Goosmann, René W.; Jethwa, Prashin; Karas, Vladimír; Miniutti, Giovanni; Guainazzi, Matteo

    2012-01-01

    X-ray reflection off the accretion disc surrounding a black hole, together with the associated broad iron K$\\alpha$ line, has been widely used to constrain the innermost accretion-flow geometry and black hole spin. Some recent measurements have revealed steep reflection emissivity profiles in a number of active galactic nuclei and X-ray binaries. We explore the physically motivated conditions that give rise to the observed steep disc-reflection emissivity profiles. We perform a set of simulat...

  2. FACTORS AFFECTING THE REMOVAL OF A BASIC AND AN AZO DYE FROM ARTIFICIAL SOLUTIONS BY ADSORPTION USING ACTIVATED CARBON

    OpenAIRE

    Albroomi, H I; ElSayed, Mohamed; Baraka, A.; Abdelmaged, M A

    2014-01-01

    Decolourisation of wastewater, particularly from textile industries, is one of the major environmental concerns these days. Current methods for removing dyes from wastewater are costly and cannot effectively be used to treat wide range of such wastewater. This work describes the use of commercial available granular activated carbon (GAC) as an efficient adsorbent material for dyes removal. Aqueous solutions of various basic dye Methylene Blue (MB) and azo-dye Tartrazine with concentrations 5-...

  3. Gravitoturbulence in magnetised protostellar discs

    CERN Document Server

    Riols, A

    2016-01-01

    Gravitational instability (GI) features in several aspects of protostellar disk evolution, most notably in angular momentum transport, fragmentation, and the outbursts exemplified by FU Ori and EX Lupi systems. The outer regions of protostellar discs may also be coupled to magnetic fields, which could then modify the development of GI. To understand the basic elements of their interaction, we perform local 2D ideal and resistive MHD simulations with an imposed toroidal field. In the regime of moderate plasma beta, we find that the system supports a hot gravito-turbulent state, characterised by considerable magnetic energy and stress and a surprisingly large Toomre parameter $Q~10$. This result has potential implications for disk structure, vertical thickness, ionisation, etc. Our simulations also reveal the existence of long-lived and dense `magnetic islands' or plasmoids. Lastly, we find that the presence of a magnetic field has little impact on the fragmentation criterion of the disk. Though our focus is on...

  4. Spontaneous Regression of Herniated Lumbar Disc with New Disc Protrusion in the Adjacent Level.

    Science.gov (United States)

    Hakan, Tayfun; Gürcan, Serkan

    2016-01-01

    Spontaneous regression of herniated lumbar discs was reported occasionally. The mechanisms proposed for regression of disc herniation are still incomplete. This paper describes and discusses a case of spontaneous regression of herniated lumbar discs with a new disc protrusion in the adjacent level. A 41-year-old man was admitted with radiating pain and numbness in the left lower extremity with a left posterolateral disc extrusion at L5-S1 level. He was admitted to hospital with low back pain due to disc herniation caudally immigrating at L4-5 level three years ago. He refused the surgical intervention that was offered and was treated conservatively at that time. He had no neurological deficit and a history of spontaneous regression of the extruded lumbar disc; so, a conservative therapy, including bed rest, physical therapy, nonsteroidal anti-inflammatory drugs, and analgesics, was advised. In conclusion, herniated lumbar disc fragments may regress spontaneously. Reports are prone to advise conservative treatment for extruded or sequestrated lumbar disc herniations. However, these patients should be followed up closely; new herniation at adjacent/different level may occur. Furthermore, it is important to know which herniated disk should be removed and which should be treated conservatively, because disc herniation may cause serious complications as muscle weakness and cauda equine syndrome. PMID:27429818

  5. Spontaneous Regression of Herniated Lumbar Disc with New Disc Protrusion in the Adjacent Level

    Directory of Open Access Journals (Sweden)

    Tayfun Hakan

    2016-01-01

    Full Text Available Spontaneous regression of herniated lumbar discs was reported occasionally. The mechanisms proposed for regression of disc herniation are still incomplete. This paper describes and discusses a case of spontaneous regression of herniated lumbar discs with a new disc protrusion in the adjacent level. A 41-year-old man was admitted with radiating pain and numbness in the left lower extremity with a left posterolateral disc extrusion at L5-S1 level. He was admitted to hospital with low back pain due to disc herniation caudally immigrating at L4-5 level three years ago. He refused the surgical intervention that was offered and was treated conservatively at that time. He had no neurological deficit and a history of spontaneous regression of the extruded lumbar disc; so, a conservative therapy, including bed rest, physical therapy, nonsteroidal anti-inflammatory drugs, and analgesics, was advised. In conclusion, herniated lumbar disc fragments may regress spontaneously. Reports are prone to advise conservative treatment for extruded or sequestrated lumbar disc herniations. However, these patients should be followed up closely; new herniation at adjacent/different level may occur. Furthermore, it is important to know which herniated disk should be removed and which should be treated conservatively, because disc herniation may cause serious complications as muscle weakness and cauda equine syndrome.

  6. The properties of discs around planets and brown dwarfs as evidence for disc fragmentation

    CERN Document Server

    Stamatellos, Dimitris

    2015-01-01

    Direct imaging searches have revealed many very low-mass objects, including a small number of planetary mass objects, as wide-orbit companions to young stars. The formation mechanism of these objects remains uncertain. In this paper we present the predictions of the disc fragmentation model regarding the properties of the discs around such low-mass objects. We find that the discs around objects that have formed by fragmentation in discs hosted by Sun-like stars (referred to as 'parent' discs and 'parent' stars) are more massive than expected from the ${M}_{\\rm disc}-M_*$ relation (which is derived for stars with masses $M_*>0.2 {\\rm M}_{\\odot}$). Accordingly, the accretion rates onto these objects are also higher than expected from the $\\dot{M}_*-M_*$ relation. Moreover there is no significant correlation between the mass of the brown dwarf or planet with the mass of its disc nor with the accretion rate from the disc onto it. The discs around objects that form by disc fragmentation have larger than expected m...

  7. Chemical separation of disc components using RAVE

    CERN Document Server

    Wojno, Jennifer; Steinmetz, Matthias; McMillan, Paul J; Matijevič, Gal; Binney, James; Wyse, Rosemary F G; Boeche, Corrado; Just, Andreas; Grebel, Eva K; Siebert, Arnaud; Bienaymé, Olivier; Gibson, Brad K; Zwitter, Tomaž; Bland-Hawthorn, Joss; Navarro, Julio F; Parker, Quentin A; Reid, Warren; Seabroke, George; Watson, Fred

    2016-01-01

    We present evidence from the RAdial Velocity Experiment (RAVE) survey of chemically separated, kinematically distinct disc components in the solar neighbourhood. We apply probabilistic chemical selection criteria to separate our sample into $\\alpha$-low (`thin disc') and $\\alpha$-high (`thick disc') components. Using newly derived distances, which will be utilized in the upcoming RAVE DR5, we explore the kinematic trends as a function of metallicity for each of the disc components. For our thin disc stars, we find a negative trend in the mean rotational velocity ($V_{\\mathrm{\\phi}}$) as a function of iron abundance ([Fe/H]). We measure a positive trend in $\\partial V_{\\mathrm{\\phi}}$/$\\partial$[Fe/H] for the thick disc, consistent with results from high-resolution surveys. We also find differences between the chemical thin and thick discs in all three components of velocity dispersion. We discuss the implications of an $\\alpha$-low, metal-rich population originating from the inner Galaxy, where the orbits of ...

  8. Stem cells sources for intervertebral disc regeneration.

    Science.gov (United States)

    Vadalà, Gianluca; Russo, Fabrizio; Ambrosio, Luca; Loppini, Mattia; Denaro, Vincenzo

    2016-05-26

    Intervertebral disc regeneration field is rapidly growing since disc disorders represent a major health problem in industrialized countries with very few possible treatments. Indeed, current available therapies are symptomatic, and surgical procedures consist in disc removal and spinal fusion, which is not immune to regardable concerns about possible comorbidities, cost-effectiveness, secondary risks and long-lasting outcomes. This review paper aims to share recent advances in stem cell therapy for the treatment of intervertebral disc degeneration. In literature the potential use of different adult stem cells for intervertebral disc regeneration has already been reported. Bone marrow mesenchymal stromal/stem cells, adipose tissue derived stem cells, synovial stem cells, muscle-derived stem cells, olfactory neural stem cells, induced pluripotent stem cells, hematopoietic stem cells, disc stem cells, and embryonic stem cells have been studied for this purpose either in vitro or in vivo. Moreover, several engineered carriers (e.g., hydrogels), characterized by full biocompatibility and prompt biodegradation, have been designed and combined with different stem cell types in order to optimize the local and controlled delivery of cellular substrates in situ. The paper overviews the literature discussing the current status of our knowledge of the different stem cells types used as a cell-based therapy for disc regeneration. PMID:27247704

  9. Shear Mechanics of the TMJ Disc

    Science.gov (United States)

    Juran, C.M.; Dolwick, M.F.; McFetridge, P.S.

    2012-01-01

    The temporomandibular joint (TMJ) is a complex hinge and gliding joint that induces significant shear loads onto the fibrocartilage TMJ disc during jaw motion. The purpose of this study was to assess regional variation in the disc’s shear loading characteristics under physiologically relevant loads and to associate those mechanical findings with common clinical observations of disc fatigue and damage. Porcine TMJ discs were compressed between an axially translating bottom platen and a 2.5-cm-diameter indenter within a hydrated testing chamber. Discs were cyclically sheared at 0.5, 1, or 5 Hz to 1, 3, or 5% shear strain. Within the anterior and intermediate regions of the disc when sheared in the anteroposterior direction, both shear and compressive moduli experienced a significant decrease from instantaneous to steady state, while the posterior region’s compressive modulus decreased approximately 5%, and no significant loss of shear modulus was noted. All regions retained their shear modulus within 0.5% of instantaneous values when shear was applied in the mediolateral direction. The results of the disc’s regional shear mechanics suggest an observable and predictable link with the common clinical observation that the posterior region of the disc is most often the zone in which fatigue occurs, which may lead to disc damage and perforation. PMID:23166043

  10. Have proto-planetary discs formed planets?

    CERN Document Server

    Greaves, J S

    2010-01-01

    It has recently been noted that many discs around T Tauri stars appear to comprise only a few Jupiter-masses of gas and dust. Using millimetre surveys of discs within six local star-formation regions, we confirm this result, and find that only a few percent of young stars have enough circumstellar material to build gas giant planets, in standard core accretion models. Since the frequency of observed exo-planets is greater than this, there is a `missing mass' problem. As alternatives to simply adjusting the conversion of dust-flux to disc mass, we investigate three other classes of solution. Migration of planets could hypothetically sweep up the disc mass reservoir more efficiently, but trends in multi-planet systems do not support such a model, and theoretical models suggest that the gas accretion timescale is too short for migration to sweep the disc. Enhanced inner-disc mass reservoirs are possible, agreeing with predictions of disc evolution through self-gravity, but not adding to millimetre dust-flux as t...

  11. Endoscopic anterior decompression in cervical disc disease

    Directory of Open Access Journals (Sweden)

    Yad Ram Yadav

    2014-01-01

    Full Text Available Background: Although microscopic anterior cervical discectomy with or without fusion are common surgical procedures for treatment of cervical herniated discs, loss of disc height, pseudarthrosis, and adjacent disc degeneration are some of the problems associated with it. This study is aimed to evaluate results of endoscopic microforaminotomy in cervical disc diseases. Materials and Methods: A prospective study of 50 patients of mono segmental soft or hard disc causing myeloradiculopathy was undertaken. A visual analogue scale (VAS for neck and arm pain and functional outcomes using the Nurick grading system were assessed. There were 28, 12, 8, and 2 patients at C5-6, C6-7, C4-5, and C3-4 levels disc diseases, respectively. Patients with two or more level disc, instabilities, disc extending more than half vertebral body height, and previous operation at the same segment were excluded. Results: Age ranged from 21 to 67 years. Average postoperative reduction in disc height, operating time, and blood loss was 1.1 mm, 110 minutes, and 30 ml, respectively. Average pre-operative VAS score for arm pain and Nurick grading was 7.6 and 2.7, which improved to 1.9 and 0.82, respectively. All patients improved; 1, 2, 3 grade improvement was seen in 10, 27, and 10 patients, respectively. There was no significant complication or any mortality. Conclusion: Although longer follow up of large number of patients is required, endoscopic microforaminotomy is a safe and an effective alternative to microscopic anterior discectomy with or without fusion.

  12. Magnetic resonance imaging of artificial lumbar disks: safety and metal artifacts

    Institute of Scientific and Technical Information of China (English)

    YANG Chang-wei; LIU Liu; WANG Jian; DONG Ai-sheng; LU Jian-ping; HE Shi-sheng; LI Ming

    2009-01-01

    Background This study was to investigate the safety of two types of commercially available lumbar artificial discs (CHARITE and PRODISC -L) during a magnetic resonance imaging (MRI) procedure in a 1.5-Tesla MR system, and to evaluate the size of metal artifacts on the MR image for different sequences.Methods A 1.5-Tesla clinical MR imaging system was used. The degree of deflection of the endplates of two artificial discs was evaluated by an angle-measurement instrument at the portals of the MRI scanner. The heating effect of the radio frequency (RF) magnetic field was evaluated by using "worst-case" imaging sequences on a human cadaver implanted with an artificial lumbar disc at the L5/S1 intervertebral disc location. The temperatures of the tissue adjacent to the implant, and of the L4/L5 intervertebral disc (used as a control) were measured, respectively, using a digital probe thermometer before and after the MRI scan sequence. A rectangular water phantom was designed to evaluate the metal artifacts of these two artificial discs under different MR imaging sequences.Results The maximal deflection angle of the endplate of the implants under a static MR field was 7.5 and 6.0 degrees, for the CHARITE and PRODISC -L, respectively. The difference between temperature rise of tissue adjacent to the two types of artificial discs and the temperature rise of the L4/L5 control location was 0.4 and 0.6℃, respectively. The size of metal artifacts on images of TSE (T1/T2-weighted), STIR and Turbo Dark Fluid sequences were relatively less than those of TSE fat saturation, Flash and SE (T1-weighted) sequences.Conclusions The CHARITE and the PRODISC -L artificial disc do not present an additional hazard or risk to a patient undergoing an MRI procedure using a scanner operating with a static magnetic field of 1.5T or lower. Image artifacts from the implants may present problems if the anatomical region of interest is in or near the area where these implants are located (e

  13. [Lumbar disc herniation and andrological diseases].

    Science.gov (United States)

    Jin, Bao-fang

    2015-10-01

    Lumbar disc herniation is a common male disease. In the past, More academic attention was directed to its relationship with lumbago and leg pain than to its association with andrological diseases. Studies show that central lumber intervertebral disc herniation may cause cauda equina injury and result in premature ejaculation, erectile dysfunction, chronic pelvic pain syndrome, priapism, and emission. This article presents an overview on the correlation between central lumbar intervertebral disc herniation and andrological diseases, focusing on the aspects of etiology, pathology, and clinical progress, hoping to invite more attention from andrological and osteological clinicians. PMID:26665671

  14. Spectroscopic properties of stars with debris discs

    International Nuclear Information System (INIS)

    The question of the origin and evolution of planetary systems is of fundamental importance for astrophysics. Dusty debris discs are signatures of planetary systems and, therefore, constitute valuable tools to provide new light in our understanding of how planetary systems form and evolve. We present the first results of a spectroscopic programme of a sample of stars with debris discs. High-resolution echelle spectra are used to determine metallicities and abundances. Properties of stars with debris discs, are compared with those of stars hosting planets, as well as 'normal' stars.

  15. Groups, cacti and framed little discs

    CERN Document Server

    Hepworth, Richard

    2010-01-01

    Let G be a topological group. Then the based loopspace of G is an algebra over the cacti operad, while the double loopspace of the classifying space of G is an algebra over the framed little discs operad. This paper shows that these two algebras are equivalent, in the sense that they are weakly equivalent E-algebras, where E is an operad weakly equivalent to both framed little discs and cacti. We recover the equivalence between cacti and framed little discs, and Menichi's isomorphism between the BV-algebras obtained by taking the homology of the loopspace of G and of the double loopspace of BG.

  16. Spectroscopic Parameters of Lumbar Intervertebral Disc Material

    Science.gov (United States)

    Terbetas, G.; Kozlovskaja, A.; Varanius, D.; Graziene, V.; Vaitkus, J.; Vaitkuviene, A.

    2009-06-01

    There are numerous methods of investigating intervertebral disc. Visualization methods are widely used in clinical practice. Histological, imunohistochemical and biochemical methods are more used in scientific research. We propose that a new spectroscopic investigation would be useful in determining intervertebral disc material, especially when no histological specimens are available. Purpose: to determine spectroscopic parameters of intervertebral disc material; to determine emission spectra common for all intervertebral discs; to create a background for further spectroscopic investigation where no histological specimen will be available. Material and Methods: 20 patients, 68 frozen sections of 20 μm thickness from operatively removed intervertebral disc hernia were excited by Nd:YAG microlaser STA-01-TH third harmonic 355 nm light throw 0, 1 mm fiber. Spectrophotometer OceanOptics USB2000 was used for spectra collection. Mathematical analysis of spectra was performed by ORIGIN multiple Gaussian peaks analysis. Results: In each specimen of disc hernia were found distinct maximal spectral peaks of 4 types supporting the histological evaluation of mixture content of the hernia. Fluorescence in the spectral regions 370-700 nm was detected in the disc hernias. The main spectral component was at 494 nm and the contribution of the components with the peak wavelength values at 388 nm, 412 nm and 435±5 nm were varying in the different groups of samples. In comparison to average spectrum of all cases, there are 4 groups of different spectral signatures in the region 400-500 nm in the patient groups, supporting a clinical data on different clinical features of the patients. Discussion and Conclusion: besides the classical open discectomy, new minimally invasive techniques of treating intervertebral disc emerge (PLDD). Intervertebral disc in these techniques is assessed by needle, no histological specimen is taken. Spectroscopic investigation via fiber optics through the

  17. Magnetorotationally driven wind cycles in local disc models

    CERN Document Server

    Riols, A; Latter, H; Ross, J P

    2016-01-01

    Jets, from the protostellar to the AGN context, have been extensively studied but their connection to the turbulent dynamics of the underlying accretion disc is poorly understood. Following a similar approach to Lesur et al. (2013), we examine the role of the magnetorotational instability (MRI) in the production and acceleration of outflows from discs. Via a suite of one-dimensional shearing-box simulations of stratified discs we show that magneto-centrifugal winds exhibit cyclic activity with a period of 10-20 Omega^{-1}, a few times the orbital period. The cycle seems to be more vigorous for strong vertical field; it is robust to the variation of relevant parameters and independent of numerical details. The convergence of these solutions (in particular the mass loss rate) with vertical box size is also studied. By considering a sequence of magnetohydrostatic equilibria and their stability, the periodic activity may be understood as the succession of the following phases: (a) a dominant MRI channel mode, (b)...

  18. Magnetorotationally driven wind cycles in local disc models

    Science.gov (United States)

    Riols, A.; Ogilvie, G. I.; Latter, H.; Ross, J. P.

    2016-09-01

    Jets, from the protostellar to the AGN context, have been extensively studied but their connection to the turbulent dynamics of the underlying accretion disc is poorly understood. Following a similar approach to Lesur et al. (2013), we examine the role of the magnetorotational instability (MRI) in the production and acceleration of outflows from discs. Via a suite of one-dimensional shearing-box simulations of stratified discs we show that magneto-centrifugal winds exhibit cyclic activity with a period of 10 - 20 Ω-1, a few times the orbital period. The cycle seems to be more vigorous for strong vertical field; it is robust to the variation of relevant parameters and independent of numerical details. The convergence of these solutions (in particular the mass loss rate) with vertical box size is also studied. By considering a sequence of magnetohydrostatic equilibria and their stability, the periodic activity may be understood as the succession of the following phases: (a) a dominant MRI channel mode, (b) strong magnetic field generation, (c) consequent wind launching, and ultimately (d) vertical expulsion of the excess magnetic field by the expanding and accelerating gas associated with the wind. We discuss potential connections between this behaviour and observed time-variability in disk-jet systems.

  19. Artificial astrocytes improve neural network performance.

    Science.gov (United States)

    Porto-Pazos, Ana B; Veiguela, Noha; Mesejo, Pablo; Navarrete, Marta; Alvarellos, Alberto; Ibáñez, Oscar; Pazos, Alejandro; Araque, Alfonso

    2011-01-01

    Compelling evidence indicates the existence of bidirectional communication between astrocytes and neurons. Astrocytes, a type of glial cells classically considered to be passive supportive cells, have been recently demonstrated to be actively involved in the processing and regulation of synaptic information, suggesting that brain function arises from the activity of neuron-glia networks. However, the actual impact of astrocytes in neural network function is largely unknown and its application in artificial intelligence remains untested. We have investigated the consequences of including artificial astrocytes, which present the biologically defined properties involved in astrocyte-neuron communication, on artificial neural network performance. Using connectionist systems and evolutionary algorithms, we have compared the performance of artificial neural networks (NN) and artificial neuron-glia networks (NGN) to solve classification problems. We show that the degree of success of NGN is superior to NN. Analysis of performances of NN with different number of neurons or different architectures indicate that the effects of NGN cannot be accounted for an increased number of network elements, but rather they are specifically due to astrocytes. Furthermore, the relative efficacy of NGN vs. NN increases as the complexity of the network increases. These results indicate that artificial astrocytes improve neural network performance, and established the concept of Artificial Neuron-Glia Networks, which represents a novel concept in Artificial Intelligence with implications in computational science as well as in the understanding of brain function. PMID:21526157

  20. Artificial astrocytes improve neural network performance.

    Directory of Open Access Journals (Sweden)

    Ana B Porto-Pazos

    Full Text Available Compelling evidence indicates the existence of bidirectional communication between astrocytes and neurons. Astrocytes, a type of glial cells classically considered to be passive supportive cells, have been recently demonstrated to be actively involved in the processing and regulation of synaptic information, suggesting that brain function arises from the activity of neuron-glia networks. However, the actual impact of astrocytes in neural network function is largely unknown and its application in artificial intelligence remains untested. We have investigated the consequences of including artificial astrocytes, which present the biologically defined properties involved in astrocyte-neuron communication, on artificial neural network performance. Using connectionist systems and evolutionary algorithms, we have compared the performance of artificial neural networks (NN and artificial neuron-glia networks (NGN to solve classification problems. We show that the degree of success of NGN is superior to NN. Analysis of performances of NN with different number of neurons or different architectures indicate that the effects of NGN cannot be accounted for an increased number of network elements, but rather they are specifically due to astrocytes. Furthermore, the relative efficacy of NGN vs. NN increases as the complexity of the network increases. These results indicate that artificial astrocytes improve neural network performance, and established the concept of Artificial Neuron-Glia Networks, which represents a novel concept in Artificial Intelligence with implications in computational science as well as in the understanding of brain function.

  1. Transradicular lumbar disc herniation: An extreme variant of intraradicular disc herniation

    OpenAIRE

    Kasliwal, Manish K.; Shimer, Adam L

    2015-01-01

    Intradural or intraradicular lumbar disc herniation (IDH) is a relatively rare condition often diagnosed intraoperatively. We encountered an extreme variant of IDH - a transradicular herniation as the disc material extruded through the lumbar nerve root through a split essentially transecting the nerve root. While failure to recognize intradural and intraradicular disc herniation can lead to failed back surgery, the variant described in the present case could lead to iatrogenic injury and com...

  2. Artificial Intelligence for the Evaluation of Operational Parameters Influencing Nitrification and Nitrifiers in an Activated Sludge Process.

    Science.gov (United States)

    Awolusi, Oluyemi Olatunji; Nasr, Mahmoud; Kumari, Sheena; Bux, Faizal

    2016-07-01

    Nitrification at a full-scale activated sludge plant treating municipal wastewater was monitored over a period of 237 days. A combination of fluorescent in situ hybridization (FISH) and quantitative real-time polymerase chain reaction (qPCR) were used for identifying and quantifying the dominant nitrifiers in the plant. Adaptive neuro-fuzzy inference system (ANFIS), Pearson's correlation coefficient, and quadratic models were employed in evaluating the plant operational conditions that influence the nitrification performance. The ammonia-oxidizing bacteria (AOB) abundance was within the range of 1.55 × 10(8)-1.65 × 10(10) copies L(-1), while Nitrobacter spp. and Nitrospira spp. were 9.32 × 10(9)-1.40 × 10(11) copies L(-1) and 2.39 × 10(9)-3.76 × 10(10) copies L(-1), respectively. Specific nitrification rate (qN) was significantly affected by temperature (r 0.726, p 0.002), hydraulic retention time (HRT) (r -0.651, p 0.009), and ammonia loading rate (ALR) (r 0.571, p 0.026). Additionally, AOB was considerably influenced by HRT (r -0.741, p 0.002) and temperature (r 0.517, p 0.048), while HRT negatively impacted Nitrospira spp. (r -0.627, p 0.012). A quadratic combination of HRT and food-to-microorganism (F/M) ratio also impacted qN (r (2) 0.50), AOB (r (2) 0.61), and Nitrospira spp. (r (2) 0.72), while Nitrobacter spp. was considerably influenced by a polynomial function of F/M ratio and temperature (r (2) 0.49). The study demonstrated that ANFIS could be used as a tool to describe the factors influencing nitrification process at full-scale wastewater treatment plants. PMID:26906468

  3. Reoperations after first lumbar disc herniation surgery; a special interest on residives during a 5-year follow-up

    Directory of Open Access Journals (Sweden)

    Kautiainen Hannu

    2007-01-01

    Full Text Available Abstract Background The overall rate of operations after recurrent lumbar disc herniation has been shown to be 3–11%. However, little is known about the rate of residives. Thus the aim of this study was to explore the cumulative rates of re-operations and especially residive disc herniations at the same side and level as the primary disc herniation after first lumbar disc herniation surgery and the factors that influence the risk of re-operations over a five year follow-up study. Methods 166 virgin lumbar disc herniation patients (mean age 42 years, 57% males were studied. Data on patients' initial disc operations and type and timing of re-operations during the follow-up were collected from patient files. Back and leg pain on visual analog scale and employment status were collected by questionnaires. Results The cumulative rate of re-operations for lumbar disc herniation was 10.2% (95% Cl 6.0 to 15.1. The rate of residives at initial site was 7.4% (95% Cl 3.7 to 11.3 and rate of lumbar disc herniations at other sites was 3.1% (95% Cl 0.6 to 6.2. The occurrence of residive lumbar disc herniations was evenly distributed across the 5 years. Neither age, gender, preoperative symptoms, physical activity nor employment had effect on the probability of re-operation. Conclusion Seven percent of the lumbar disc patients had a residive lumbar disc operation within five years of their first operation. No specific factors influencing the risk for re-operation were found.

  4. Archival-grade optical disc design and international standards

    Science.gov (United States)

    Fujii, Toru; Kojyo, Shinichi; Endo, Akihisa; Kodaira, Takuo; Mori, Fumi; Shimizu, Atsuo

    2015-09-01

    Optical discs currently on the market exhibit large variations in life span among discs, making them unsuitable for certain business applications. To assess and potentially mitigate this problem, we performed accelerated degradation testing under standard ISO conditions, determined the probable disc failure mechanisms, and identified the essential criteria necessary for a stable disc composition. With these criteria as necessary conditions, we analyzed the physical and chemical changes that occur in the disc components, on the basis of which we determined technological measures to reduce these degradation processes. By applying these measures to disc fabrication, we were able to develop highly stable optical discs.

  5. Stellar motion induced by gravitational instabilities in protoplanetary discs

    Science.gov (United States)

    Michael, Scott; Durisen, R. H.

    2010-07-01

    We test the effect of assumptions about stellar motion on the behaviour of gravitational instabilities (GIs) in protoplanetary discs around solar-type stars by performing two simulations that are identical in all respects except the treatment of the star. In one simulation, the star is assumed to remain fixed at the centre of the inertial reference frame. In the other, stellar motion is handled properly by including an indirect potential in the hydrodynamic equations to model the star's reference frame as one which is accelerated by star/disc interactions. The discs in both simulations orbit a solar mass star, initially extend from 2.3 to 40 au with a ϖ-1/2 surface density profile, and have a total mass of 0.14 Msolar. The γ = 5/3 ideal gas is assumed to cool everywhere with a constant cooling time of two outer rotation periods. The overall behaviour of the disc evolution is similar, except for weakening in various measures of GI activity by about at most tens of per cent for the indirect potential case. Overall conclusions about disc evolution in earlier papers by our group, where the star was always assumed to be fixed in an inertial frame, remain valid. There is no evidence for independent one-armed instabilities, like the Stimulation by the Long-range Interaction of Newtonian Gravity (SLING), in either simulation. On the other hand, the stellar motion about the system centre of mass (COM) in the simulation with the indirect potential is substantial, up to 0.25 au during the burst phase, as GIs initiate, and averaging about 0.9 au during the asymptotic phase, when the GIs reach an overall balance of heating and cooling. These motions appear to be a stellar response to non-linear interactions between discrete global spiral modes in both the burst and asymptotic phases of the evolution, and the star's orbital motion about the COM reflects the orbit periods of disc material near the corotation radii of the dominant spiral waves. This motion is, in principle

  6. Treatment of lumbar disc herniation by percutaneous laser disc decompression (PLDD) and modified PLDD

    Science.gov (United States)

    Chi, Xiao fei; Li, Hong zhi; Wu, Ru zhou; Sui, Yun xian

    2005-07-01

    Objective: To study the micro-invasive operative method and to compare the effect of treatment of PLDD and modified PLDD for Lumbar Disc Herniation. Method: Vaporized part of the nucleus pulposus in single or multiple point after acupuncture into lumbar disc, to reach the purpose of the decompression of the lumbar disc. Result: Among the 19 cases of the regular PLDD group, the excellent and good rate was 63.2%, and among the 40 cases of the modified PLDD group, the excellent and good rate was 82.5%. Conclusion: The modified PLDD has good effect on the treatment for lumbar disc herniation.

  7. Transradicular lumbar disc herniation: An extreme variant of intraradicular disc herniation

    Directory of Open Access Journals (Sweden)

    Manish K Kasliwal

    2015-01-01

    Full Text Available Intradural or intraradicular lumbar disc herniation (IDH is a relatively rare condition often diagnosed intraoperatively. We encountered an extreme variant of IDH - a transradicular herniation as the disc material extruded through the lumbar nerve root through a split essentially transecting the nerve root. While failure to recognize intradural and intraradicular disc herniation can lead to failed back surgery, the variant described in the present case could lead to iatrogenic injury and complication if not recognized. A unique case of transradicular lumbar disc herniation in a 25-year-old patient is presented with the depiction of intraoperative images supplementing the text.

  8. Axial T2* mapping in intervertebral discs: a new technique for assessment of intervertebral disc degeneration

    Energy Technology Data Exchange (ETDEWEB)

    Hoppe, Sven; Quirbach, Sebastian; Krause, Fabian G.; Benneker, Lorin M. [Inselspital, Berne University Hospital, Department of Orthopaedic Surgery, Berne (Switzerland); Mamisch, Tallal C. [Inselspital, Berne University Hospital, Department of Radiology, Berne (Switzerland); Werlen, Stefan [Clinic Sonnenhof, Department of Radiology, Berne (Switzerland)

    2012-09-15

    To demonstrate the potential benefits of biochemical axial T2* mapping of intervertebral discs (IVDs) regarding the detection and grading of early stages of degenerative disc disease using 1.5-Tesla magnetic resonance imaging (MRI) in a clinical setting. Ninety-three patients suffering from lumbar spine problems were examined using standard MRI protocols including an axial T2* mapping protocol. All discs were classified morphologically and grouped as ''healthy'' or ''abnormal''. Differences between groups were analysed regarding to the specific T2* pattern at different regions of interest (ROIs). Healthy intervertebral discs revealed a distinct cross-sectional T2* value profile: T2* values were significantly lower in the annulus fibrosus compared with the nucleus pulposus (P = 0.01). In abnormal IVDs, T2* values were significantly lower, especially towards the centre of the disc representing the expected decreased water content of the nucleus (P = 0.01). In herniated discs, ROIs within the nucleus pulposus and ROIs covering the annulus fibrosus showed decreased T2* values. Axial T2* mapping is effective to detect early stages of degenerative disc disease. There is a potential benefit of axial T2* mapping as a diagnostic tool, allowing the quantitative assessment of intervertebral disc degeneration. circle Axial T2* mapping effective in detecting early degenerative disc disease. (orig.)

  9. Axial T2* mapping in intervertebral discs: a new technique for assessment of intervertebral disc degeneration

    International Nuclear Information System (INIS)

    To demonstrate the potential benefits of biochemical axial T2* mapping of intervertebral discs (IVDs) regarding the detection and grading of early stages of degenerative disc disease using 1.5-Tesla magnetic resonance imaging (MRI) in a clinical setting. Ninety-three patients suffering from lumbar spine problems were examined using standard MRI protocols including an axial T2* mapping protocol. All discs were classified morphologically and grouped as ''healthy'' or ''abnormal''. Differences between groups were analysed regarding to the specific T2* pattern at different regions of interest (ROIs). Healthy intervertebral discs revealed a distinct cross-sectional T2* value profile: T2* values were significantly lower in the annulus fibrosus compared with the nucleus pulposus (P = 0.01). In abnormal IVDs, T2* values were significantly lower, especially towards the centre of the disc representing the expected decreased water content of the nucleus (P = 0.01). In herniated discs, ROIs within the nucleus pulposus and ROIs covering the annulus fibrosus showed decreased T2* values. Axial T2* mapping is effective to detect early stages of degenerative disc disease. There is a potential benefit of axial T2* mapping as a diagnostic tool, allowing the quantitative assessment of intervertebral disc degeneration. circle Axial T2* mapping effective in detecting early degenerative disc disease. (orig.)

  10. Appearance of Keplerian discs orbiting Kerr superspinars

    CERN Document Server

    Stuchlik, Zdenek; 10.1088/0264-9381/27/21/215017

    2011-01-01

    We study optical phenomena related to appearance of Keplerian accretion discs orbiting Kerr superspinars predicted by the string theory. The superspinar exterior is described by the standard Kerr naked singularity geometry breaking the black hole limit on the internal angular momentum (spin). We construct local photon escape cones for a variety of orbiting sources that enable to determine the superspinars silhouette in the case of distant observers. We show that the superspinar silhouette depends strongly on the assumed edge where the external Kerr spacetime is joined to the internal spacetime governed by the string theory and significantly differs from the black hole silhouette. The appearance of the accretion disc is strongly dependent on the value of the superspinar spin in both their shape and frequency shift profile. Apparent extension of the disc grows significantly with growing spin, while the frequency shift grows with descending spin. This behavior differs substantially from appearance of discs orbit...

  11. Eclipse Mapping: Astrotomography of Accretion Discs

    CERN Document Server

    Baptista, Raymundo

    2015-01-01

    The Eclipse Mapping Method is an indirect imaging technique that transforms the shape of the eclipse light curve into a map of the surface brightness distribution of the occulted regions. Three decades of application of this technique to the investigation of the structure, the spectrum and the time evolution of accretion discs around white dwarfs in cataclysmic variables have enriched our understanding of these accretion devices with a wealth of details such as (but not limited to) moving heating/cooling waves during outbursts in dwarf novae, tidally-induced spiral shocks of emitting gas with sub-Keplerian velocities, elliptical precessing discs associated to superhumps, and measurements of the radial run of the disc viscosity through the mapping of the disc flickering sources. This chapter reviews the principles of the method, discusses its performance, limitations, useful error propagation procedures, as well as highlights a selection of applications aimed at showing the possible scientific problems that ha...

  12. Only marginal alignment of disc galaxies

    CERN Document Server

    Andrae, Rene

    2011-01-01

    Testing theories of angular-momentum acquisition of rotationally supported disc galaxies is the key to understand the formation of this type of galaxies. The tidal-torque theory tries to explain this acquisition process in a cosmological framework and predicts positive autocorrelations of angular-momentum orientation and spiral-arm handedness on distances of 1Mpc/h. This disc alignment can also cause systematic effects in weak-lensing measurements. Previous observations claimed discovering such correlations but did not account for errors in redshift, ellipticity and morphological classifications. We explain how to rigorously propagate all important errors. Analysing disc galaxies in the SDSS database, we find that positive autocorrelations of spiral-arm handedness and angular-momentum orientations on distances of 1Mpc/h are plausible but not statistically significant. This result agrees with a simple hypothesis test in the Local Group, where we find no evidence for disc alignment. Moreover, we demonstrate tha...

  13. The lowest surface brightness disc galaxy known

    International Nuclear Information System (INIS)

    The discovery of a galaxy with a prominent bulge and a dominant extremely low surface brightness disc component is reported. The profile of this galaxy is very similar to the recently discovered giant low surface brightness galaxy Malin 1. The disc central surface brightness is found to be ∼ 26.4 Rμ, some 1.5 mag fainter than Malin 1 and thus by far the lowest yet observed. (author)

  14. Low back pain and degenerative disc disease

    OpenAIRE

    Jandrić Slavica; Antić Branislav

    2006-01-01

    Introduction. Various clinical conditions can cause low back pain, and in most cases it is of a degenerative origin. Degenerative disc disease is a common condition which affects young to middle-aged men and women equally. Changes in the mechanical properties of the disc lead to degenerative arthritis in the intervertebral joints, osteophytes, and narrowing the intervertebral foramen or the spinal canal. Pathophysiology. Degenerative cascade, described by Kirkaldy-Willis, is the widely accept...

  15. Mach disc formation in cylindrical recovery systems

    Energy Technology Data Exchange (ETDEWEB)

    Morris, C.E.; McQueen, R.G.; Marsh, S.P.

    1983-01-01

    Cylindrical recovery systems have been used to shock-load polymers to pressures exceeding 50 GPa. In order to determine the pressures generated in these recovery systems the formation of the Mach disc on axis and its approach to steady state was monitored. The relation of the Mach disc diameter to the lateral dimension of the high explosive used to compress the polymer samples was also investigated.

  16. Design concepts in lumbar total disc arthroplasty

    OpenAIRE

    Galbusera, Fabio; Bellini, Chiara M.; Zweig, Thomas; Ferguson, Stephen; Raimondi, Manuela T.; Lamartina, Claudio; Brayda-bruno, Marco; Fornari, Maurizio

    2008-01-01

    The implantation of lumbar disc prostheses based on different design concepts is widely accepted. This paper reviews currently available literature studies on the biomechanics of TDA in the lumbar spine, and is targeted at the evaluation of possible relationships between the aims of TDA and the geometrical, mechanical and material properties of the various available disc prostheses. Both theoretical and experimental studies were analyzed, by a PUBMED search (performed in February 2007, revise...

  17. Do We Need Biomarkers for Disc Degeneration?

    OpenAIRE

    Gruber, Helen E.; Edward N. Hanley, Jr.

    2007-01-01

    Disc degeneration plays a major role in this country's medical, social and economic structure. The life-time prevalence of low back pain, which has disc degeneration as its cause, is about 80% in the general population. It is a primary cause of disability and estimated costs related to low back disorders exceed $100 billion per year in the U.S. alone. Biomarkers are becoming increasingly important as indicators of the presence of disease, and in evaluating outcomes during clinical treatment. ...

  18. Mach disc formation in cylindrical recovery systems

    International Nuclear Information System (INIS)

    Cylindrical recovery systems have been used to shock-load polymers to pressures exceeding 50 GPa. In order to determine the pressures generated in these recovery systems the formation of the Mach disc on axis and its approach to steady state was monitored. The relation of the Mach disc diameter to the lateral dimension of the high explosive used to compress the polymer samples was also investigated

  19. Hard Discs on the Hyperbolic Plane

    OpenAIRE

    Modes, Carl D.; Kamien, Randall D.

    2007-01-01

    We examine a simple hard disc fluid with no long range interactions on the two dimensional space of constant negative Gaussian curvature, the hyperbolic plane. This geometry provides a natural mechanism by which global crystalline order is frustrated, allowing us to construct a tractable model of disordered monodisperse hard discs. We extend free area theory and the virial expansion to this regime, deriving the equation of state for the system, and compare its predictions with simulation near...

  20. Inflammation in intervertebral disc degeneration and regeneration

    OpenAIRE

    Molinos, Maria; Almeida, Catarina R.; Caldeira, Joana; Cunha, Carla; Gonçalves, Raquel M.; Barbosa, Mário A.

    2015-01-01

    Intervertebral disc (IVD) degeneration is one of the major causes of low back pain, a problem with a heavy economic burden, which has been increasing in prevalence as populations age. Deeper knowledge of the complex spatial and temporal orchestration of cellular interactions and extracellular matrix remodelling is critical to improve current IVD therapies, which have so far proved unsatisfactory. Inflammation has been correlated with degenerative disc disease but its role in discogenic pain a...