Sample records for advanced nodal method

  1. Advanced nodal neutron diffusion method with space-dependent cross sections: ILLICO-VX

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rajic, H.L.; Ougouag, A.M.

    1987-01-01

    Advanced transverse integrated nodal methods for neutron diffusion developed since the 1970s require that node- or assembly-homogenized cross sections be known. The underlying structural heterogeneity can be accurately accounted for in homogenization procedures by the use of heterogeneity or discontinuity factors. Other (milder) types of heterogeneity, burnup-induced or due to thermal-hydraulic feedback, can be resolved by explicitly accounting for the spatial variations of material properties. This can be done during the nodal computations via nonlinear iterations. The new method has been implemented in the code ILLICO-VX (ILLICO variable cross-section method). Numerous numerical tests were performed. As expected, the convergence ratemore » of ILLICO-VX is lower than that of ILLICO, requiring approx. 30% more outer iterations per k/sub eff/ computation. The methodology has also been implemented as the NOMAD-VX option of the NOMAD, multicycle, multigroup, two- and three-dimensional nodal diffusion depletion code. The burnup-induced heterogeneities (space dependence of cross sections) are calculated during the burnup steps.« less

  2. Outcomes of Patients With Head-and-Neck Cancer of Unknown Primary Origin Treated With Intensity-Modulated Radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shoushtari, Asal; Saylor, Drew; Kerr, Kara-Lynne

    2011-11-01

    Purpose: To analyze survival, failure patterns, and toxicity in patients with head-and-neck carcinoma of unknown primary origin (HNCUP) treated with intensity-modulated radiotherapy (IMRT). Methods and materials: Records from 27 patients with HNCUP treated during the period 2002-2008 with IMRT were reviewed retrospectively. Nodal staging ranged from N1 to N3. The mean preoperative dose to gross or suspected disease, Waldeyer's ring, and uninvolved bilateral cervical nodes was 59.4, 53.5, and 51.0 Gy, respectively. Sixteen patients underwent neck dissection after radiation and 4 patients before radiation. Eight patients with advanced nodal disease (N2b-c, N3) or extracapsular extension received chemotherapy. Results: With amore » median follow-up of 41.9 months (range, 25.3-93.9 months) for nondeceased patients, the 5-year actuarial overall survival, disease-free survival, and nodal control rates were 70.9%, 85.2%, and 88.5%, respectively. Actuarial disease-free survival rates for N1, N2, and N3 disease were 100%, 94.1%, and 50.0%, respectively, at 5 years. When stratified by nonadvanced (N1, N2a nodal disease without extracapsular spread) vs. advanced nodal disease (N2b, N2c, N3), the 5-year actuarial disease-free survival rate for the nonadvanced nodal disease group was 100%, whereas for the advanced nodal disease group it was significantly lower at 66.7% (p = 0.017). Three nodal recurrences were observed: in 1 patient with bulky N2b disease and 2 in patients with N3 disease. No nodal failures occurred in patients with N1 or N2a disease who received only radiation and surgery. Conclusion: Definitive IMRT to 50-56 Gy followed by neck dissection results in excellent nodal control and overall and disease-free survival, with acceptable toxicity for patients with T0N1 or nonbulky T0N2a disease without extracapsular spread. Patients with extracapsular spread, advanced N2 disease, or N3 disease may benefit from concurrent chemotherapy, targeted therapeutic agents, or accelerated radiation regimens in addition to surgery.« less

  3. Optimized planning methodologies of ASON implementation

    NASA Astrophysics Data System (ADS)

    Zhou, Michael M.; Tamil, Lakshman S.

    2005-02-01

    Advanced network planning concerns effective network-resource allocation for dynamic and open business environment. Planning methodologies of ASON implementation based on qualitative analysis and mathematical modeling are presented in this paper. The methodology includes method of rationalizing technology and architecture, building network and nodal models, and developing dynamic programming for multi-period deployment. The multi-layered nodal architecture proposed here can accommodate various nodal configurations for a multi-plane optical network and the network modeling presented here computes the required network elements for optimizing resource allocation.

  4. Structural insights into the interaction of a monoclonal antibody and Nodal peptides by STD-NMR spectroscopy.

    PubMed

    Calvanese, Luisa; Focà, Annalia; Sandomenico, Annamaria; Focà, Giuseppina; Caporale, Andrea; Doti, Nunzianna; Iaccarino, Emanuela; Leonardi, Antonio; D'Auria, Gabriella; Ruvo, Menotti; Falcigno, Lucia

    2017-12-15

    Nodal is a growth factor expressed during early embryonic development, but reactivated in several advanced-stage cancers. Targeting of Nodal signaling, which occurs via the binding to Cripto-1 co-receptor, results in inhibition of cell aggressiveness and reduced tumor growth. The Nodal binding region to Cripto-1 was identified and targeted with a high affinity monoclonal antibody (3D1). By STD-NMR technique, we investigated the interaction of Nodal fragments with 3D1 with the aim to elucidate at atomic level the interaction surface. Data indicate with high accuracy the antibody-antigen contact atoms and confirm the information previously obtained by immune-enzymatic methods. Main residues contacted by 3D1 are P46, V47, E49 and E50, which belong to the Nodal loop involved in the interaction with the co-receptor. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Risk of Nodal Metastasis in Major Salivary Gland Adenoid Cystic Carcinoma.

    PubMed

    Megwalu, Uchechukwu C; Sirjani, Davud

    2017-04-01

    Objective To determine the risk of nodal metastasis, examine risk factors for nodal metastasis, and evaluate the impact of nodal metastasis on survival in patients with major salivary gland adenoid cystic carcinoma. Study Design Retrospective cohort study from a large population- based cancer database. Methods Data were extracted from the SEER 18 database (Surveillance, Epidemiology, and End Results) of the National Cancer Institute. The study cohort included 720 patients diagnosed with major salivary gland adenoid cystic carcinoma between 1988 and 2013. Results The overall rate of lymph node metastasis was 17%. T3 disease (odds ratio, 4.74) and T4 disease (odds ratio, 9.24) were associated with increased risk of nodal metastasis. Age, sex, and site were not associated with nodal metastasis. Nodal metastasis was associated with worse overall survival (hazard ratio, 2.56) and disease-specific survival (hazard ratio, 3.27), after adjusting for T stage, presence of distant metastasis, site, surgical resection, radiotherapy, neck dissection, age, sex, race, marital status, and year of diagnosis. Conclusion Major salivary gland adenoid cystic carcinoma carries significant risk of nodal metastasis. Advanced T stage is associated with increased risk of nodal metastasis. Nodal metastasis is associated with worse survival.

  6. A stiffness derivative finite element technique for determination of crack tip stress intensity factors

    NASA Technical Reports Server (NTRS)

    Parks, D. M.

    1974-01-01

    A finite element technique for determination of elastic crack tip stress intensity factors is presented. The method, based on the energy release rate, requires no special crack tip elements. Further, the solution for only a single crack length is required, and the crack is 'advanced' by moving nodal points rather than by removing nodal tractions at the crack tip and performing a second analysis. The promising straightforward extension of the method to general three-dimensional crack configurations is presented and contrasted with the practical impossibility of conventional energy methods.

  7. Super-nodal methods for space-time kinetics

    NASA Astrophysics Data System (ADS)

    Mertyurek, Ugur

    The purpose of this research has been to develop an advanced Super-Nodal method to reduce the run time of 3-D core neutronics models, such as in the NESTLE reactor core simulator and FORMOSA nuclear fuel management optimization codes. Computational performance of the neutronics model is increased by reducing the number of spatial nodes used in the core modeling. However, as the number of spatial nodes decreases, the error in the solution increases. The Super-Nodal method reduces the error associated with the use of coarse nodes in the analyses by providing a new set of cross sections and ADFs (Assembly Discontinuity Factors) for the new nodalization. These so called homogenization parameters are obtained by employing consistent collapsing technique. During this research a new type of singularity, namely "fundamental mode singularity", is addressed in the ANM (Analytical Nodal Method) solution. The "Coordinate Shifting" approach is developed as a method to address this singularity. Also, the "Buckling Shifting" approach is developed as an alternative and more accurate method to address the zero buckling singularity, which is a more common and well known singularity problem in the ANM solution. In the course of addressing the treatment of these singularities, an effort was made to provide better and more robust results from the Super-Nodal method by developing several new methods for determining the transverse leakage and collapsed diffusion coefficient, which generally are the two main approximations in the ANM methodology. Unfortunately, the proposed new transverse leakage and diffusion coefficient approximations failed to provide a consistent improvement to the current methodology. However, improvement in the Super-Nodal solution is achieved by updating the homogenization parameters at several time points during a transient. The update is achieved by employing a refinement technique similar to pin-power reconstruction. A simple error analysis based on the relative residual in the 3-D few group diffusion equation at the fine mesh level is also introduced in this work.

  8. Intensity-Modulated Proton Therapy for Elective Nodal Irradiation and Involved-Field Radiation in the Definitive Treatment of Locally Advanced Non-Small Cell Lung Cancer: A Dosimetric Study

    PubMed Central

    Kesarwala, Aparna H.; Ko, Christine J.; Ning, Holly; Xanthopoulos, Eric; Haglund, Karl E.; O’Meara, William P.; Simone, Charles B.; Rengan, Ramesh

    2015-01-01

    Background Photon involved-field radiation therapy (IFRT), the standard for locally advanced non-small cell lung cancer (LA-NSCLC), results in favorable outcomes without increased isolated nodal failures, perhaps from scattered dose to elective nodal stations. Given the high conformality of intensity-modulated proton therapy (IMPT), proton IFRT could increase nodal failures. We investigated the feasibility of IMPT for elective nodal irradiation (ENI) in LA-NSCLC. Materials and Methods IMPT IFRT plans were generated to the same total dose of 66.6–72 Gy received by 20 LA-NSCLC patients treated with photon IFRT. IMPT ENI plans were generated to 46 CGE to elective nodal (EN) planning treatment volumes (PTV) plus 24 CGE to involved field (IF)-PTVs. Results Proton IFRT and ENI both improved D95 involved field (IF)-PTV coverage by 4% (p<0.01) compared to photon IFRT. All evaluated dosimetric parameters improved significantly with both proton plans. Lung V20 and mean lung dose decreased 18% (p<0.01) and 36% (p<0.01), respectively, with proton IFRT and 11% (p=0.03) and 26% (p<0.01) with ENI. Mean esophagus dose decreased 16% with IFRT and 12% with ENI; heart V25 decreased 63% with both (all p<0.01). Conclusions This study demonstrates the feasibility of IMPT for LA-NSCLC ENI. Potential decreased toxicity indicates IMPT could allow ENI while maintaining a favorable therapeutic ratio compared to photon IFRT. PMID:25604729

  9. Automatic two- and three-dimensional mesh generation based on fuzzy knowledge processing

    NASA Astrophysics Data System (ADS)

    Yagawa, G.; Yoshimura, S.; Soneda, N.; Nakao, K.

    1992-09-01

    This paper describes the development of a novel automatic FEM mesh generation algorithm based on the fuzzy knowledge processing technique. A number of local nodal patterns are stored in a nodal pattern database of the mesh generation system. These nodal patterns are determined a priori based on certain theories or past experience of experts of FEM analyses. For example, such human experts can determine certain nodal patterns suitable for stress concentration analyses of cracks, corners, holes and so on. Each nodal pattern possesses a membership function and a procedure of node placement according to this function. In the cases of the nodal patterns for stress concentration regions, the membership function which is utilized in the fuzzy knowledge processing has two meanings, i.e. the “closeness” of nodal location to each stress concentration field as well as “nodal density”. This is attributed to the fact that a denser nodal pattern is required near a stress concentration field. What a user has to do in a practical mesh generation process are to choose several local nodal patterns properly and to designate the maximum nodal density of each pattern. After those simple operations by the user, the system places the chosen nodal patterns automatically in an analysis domain and on its boundary, and connects them smoothly by the fuzzy knowledge processing technique. Then triangular or tetrahedral elements are generated by means of the advancing front method. The key issue of the present algorithm is an easy control of complex two- or three-dimensional nodal density distribution by means of the fuzzy knowledge processing technique. To demonstrate fundamental performances of the present algorithm, a prototype system was constructed with one of object-oriented languages, Smalltalk-80 on a 32-bit microcomputer, Macintosh II. The mesh generation of several two- and three-dimensional domains with cracks, holes and junctions was presented as examples.

  10. Elective nodal irradiation (ENI) vs. involved field radiotherapy (IFRT) for locally advanced non-small cell lung cancer (NSCLC): A comparative analysis of toxicities and clinical outcomes.

    PubMed

    Fernandes, Annemarie T; Shen, Jason; Finlay, Jarod; Mitra, Nandita; Evans, Tracey; Stevenson, James; Langer, Corey; Lin, Lilie; Hahn, Stephen; Glatstein, Eli; Rengan, Ramesh

    2010-05-01

    Elective nodal irradiation (ENI) and involved field radiotherapy (IFRT) are definitive radiotherapeutic approaches used to treat patients with locally advanced non-small cell lung cancer (NSCLC). ENI delivers prophylactic radiation to clinically uninvolved lymph nodes, while IFRT only targets identifiable gross nodal disease. Because clinically uninvolved nodal stations may harbor microscopic disease, IFRT raises concerns for increased nodal failures. This retrospective cohort analysis evaluates failure rates and treatment-related toxicities in patients treated at a single institution with ENI and IFRT. We assessed all patients with stage III locally advanced or stage IV oligometastatic NSCLC treated with definitive radiotherapy from 2003 to 2008. Each physician consistently treated with either ENI or IFRT, based on their treatment philosophy. Of the 108 consecutive patients assessed (60 ENI vs. 48 IFRT), 10 patients had stage IV disease and 95 patients received chemotherapy. The median follow-up time for survivors was 18.9 months. On multivariable logistic regression analysis, patients treated with IFRT demonstrated a significantly lower risk of high grade esophagitis (Odds ratio: 0.31, p = 0.036). The differences in 2-year local control (39.2% vs. 59.6%), elective nodal control (84.3% vs. 84.3%), distant control (47.7% vs. 52.7%) and overall survival (40.1% vs. 43.7%) rates were not statistically significant between ENI vs. IFRT. Nodal failure rates in clinically uninvolved nodal stations were not increased with IFRT when compared to ENI. IFRT also resulted in significantly decreased esophageal toxicity, suggesting that IFRT may allow for integration of concurrent systemic chemotherapy in a greater proportion of patients. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  11. Mapping of nodal disease in locally advanced prostate cancer: Rethinking the clinical target volume for pelvic nodal irradiation based on vascular rather than bony anatomy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shih, Helen A.; Harisinghani, Mukesh; Zietman, Anthony L.

    2005-11-15

    Purpose: Toxicity from pelvic irradiation could be reduced if fields were limited to likely areas of nodal involvement rather than using the standard 'four-field box.' We employed a novel magnetic resonance lymphangiographic technique to highlight the likely sites of occult nodal metastasis from prostate cancer. Methods and Materials: Eighteen prostate cancer patients with pathologically confirmed node-positive disease had a total of 69 pathologic nodes identifiable by lymphotropic nanoparticle-enhanced MRI and semiquantitative nodal analysis. Fourteen of these nodes were in the para-aortic region, and 55 were in the pelvis. The position of each of these malignant nodes was mapped to amore » common template based on its relation to skeletal or vascular anatomy. Results: Relative to skeletal anatomy, nodes covered a diffuse volume from the mid lumbar spine to the superior pubic ramus and along the sacrum and pelvic side walls. In contrast, the nodal metastases mapped much more tightly relative to the large pelvic vessels. A proposed pelvic clinical target volume to encompass the region at greatest risk of containing occult nodal metastases would include a 2.0-cm radial expansion volume around the distal common iliac and proximal external and internal iliac vessels that would encompass 94.5% of the pelvic nodes at risk as defined by our node-positive prostate cancer patient cohort. Conclusions: Nodal metastases from prostate cancer are largely localized along the major pelvic vasculature. Defining nodal radiation treatment portals based on vascular rather than bony anatomy may allow for a significant decrease in normal pelvic tissue irradiation and its associated toxicities.« less

  12. Prognostic impact of the level of nodal involvement: retrospective analysis of patients with advanced oral squamous cell carcinoma.

    PubMed

    Murakami, R; Nakayama, H; Semba, A; Hiraki, A; Nagata, M; Kawahara, K; Shiraishi, S; Hirai, T; Uozumi, H; Yamashita, Y

    2017-01-01

    We retrospectively evaluated the prognostic impact of the level of nodal involvement in patients with advanced oral squamous cell carcinoma (SCC). Between 2005 and 2010, 105 patients with clinical stage III or IV oral SCC had chemoradiotherapy preoperatively. Clinical (cN) and pathological nodal (pN) involvement was primarily at levels Ib and II. We defined nodal involvement at levels Ia and III-V as anterior and inferior extensions, respectively, and recorded such findings as extensive. With respect to pretreatment variables (age, clinical stage, clinical findings of the primary tumour, and nodal findings), univariate analysis showed that extensive cN was the only significant factor for overall survival (hazard ratio [HR], 3.27; 95% CI 1.50 to 7.13; p=0.001). Univariate analysis showed that all pN findings, including the nodal classification (invaded nodes, multiple, and contralateral) and extensive involvement were significant, and multivariate analysis confirmed that extensive pN (HR 4.71; 95% CI 1.85 to 11.97; p=0.001) and multiple pN (HR 2.59; 95% CI 1.10 to 6.09; p=0.029) were independent predictors of overall survival. Assessment based on the level of invaded neck nodes may be a better predictor of survival than the current nodal classification. Copyright © 2016 The British Association of Oral and Maxillofacial Surgeons. Published by Elsevier Ltd. All rights reserved.

  13. Involved-Field Radiotherapy versus Elective Nodal Irradiation in Combination with Concurrent Chemotherapy for Locally Advanced Non-Small Cell Lung Cancer: A Prospective Randomized Study

    PubMed Central

    Chen, Ming; Bao, Yong; Ma, Hong-Lian; Wang, Jin; Wang, Yan; Peng, Fang; Zhou, Qi-Chao; Xie, Cong-Hua

    2013-01-01

    This prospective randomized study is to evaluate the locoregional failure and its impact on survival by comparing involved field radiotherapy (IFRT) with elective nodal irradiation (ENI) in combination with concurrent chemotherapy for locally advanced non-small cell lung cancer. It appears that higher dose could be delivered in IFRT arm than that in ENI arm, and IFRT did not increase the risk of initially uninvolved or isolated nodal failures. Both a tendency of improved locoregional progression-free survival and a significant increased overall survival rate are in favor of IFRT arm in this study. PMID:23762840

  14. Recognizing nodal marginal zone lymphoma: recent advances and pitfalls. A systematic review

    PubMed Central

    van den Brand, Michiel; van Krieken, J. Han J.M.

    2013-01-01

    The diagnosis of nodal marginal zone lymphoma is one of the remaining problem areas in hematopathology. Because no established positive markers exist for this lymphoma, it is frequently a diagnosis of exclusion, making distinction from other low-grade B-cell lymphomas difficult or even impossible. This systematic review summarizes and discusses the current knowledge on nodal marginal zone lymphoma, including clinical features, epidemiology and etiology, histology, and cytogenetic and molecular features. In particular, recent advances in diagnostics and pathogenesis are discussed. New immunohistochemical markers have become available that could be used as positive markers for nodal marginal zone lymphoma. These markers could be used to ensure more homogeneous study groups in future research. Also, recent gene expression studies and studies describing specific gene mutations have provided clues to the pathogenesis of nodal marginal zone lymphoma, suggesting deregulation of the nuclear factor kappa B pathway. Nevertheless, nodal marginal zone lymphoma remains an enigmatic entity, requiring further study to define its pathogenesis to allow an accurate diagnosis and tailored treatment. However, recent data indicate that it is not related to splenic or extranodal lymphoma, and that it is also not related to lymphoplasmacytic lymphoma. Thus, even though the diagnosis is not always easy, it is clearly a separate entity. PMID:23813646

  15. Preoperative axillary lymph node evaluation in breast cancer patients by breast magnetic resonance imaging (MRI): Can breast MRI exclude advanced nodal disease?

    PubMed

    Hyun, Su Jeong; Kim, Eun-Kyung; Moon, Hee Jung; Yoon, Jung Hyun; Kim, Min Jung

    2016-11-01

    To evaluate the diagnostic performance of breast magnetic resonance imaging (MRI) in preoperative evaluation of axillary lymph node metastasis (ALNM) in breast cancer patients and to assess whether breast MRI can be used to exclude advanced nodal disease. A total of 425 patients were included in this study and breast MRI findings were retrospectively reviewed. The diagnostic performance of breast MRI for diagnosis of ALNM was evaluated in all patients, patients with neoadjuvant chemotherapy (NAC), and those without NAC (no-NAC). We evaluated whether negative MRI findings (cN0) can exclude advanced nodal disease (pN2-pN3) using the negative predictive value (NPV) in each group. The sensitivity and NPV of breast MRI in evaluation of ALNM was 51.3 % (60/117) and 83.3 % (284/341), respectively. For cN0 cases on MRI, pN2-pN3 manifested in 1.8 % (6/341) of the overall patients, 0.4 % (1/257) of the no-NAC group, and 6 % (5/84) of the NAC group. The NPV of negative MRI findings for exclusion of pN2-pN3 was higher for the no-NAC group than for the NAC group (99.6 % vs. 94.0 %, p = 0.039). Negative MRI findings (cN0) can exclude the presence of advanced nodal disease with an NPV of 99.6 % in the no-NAC group. • Breast MRI can be used to exclude advanced nodal disease (pN2-3). • Negative MRI allows breast cancer patients to avoid unnecessary axillary surgery (98.2 %). • Negative MRI findings exclude 99.6 % of pN2-pN3 in the no-NAC group. • Negative MRI findings exclude 96.0 % of pN2-pN3 in the NAC group.

  16. Fluorodeoxyglucose positron emission tomography–computed tomography in evaluation of pelvic and para-aortic nodal involvement in early stage and operable cervical cancer: Comparison with surgicopathological findings

    PubMed Central

    Bansal, Vandana; Damania, Kaizad; Sharma, Anshu Rajnish

    2011-01-01

    Introduction: Nodal metastases in cervical cancer have prognostic implications. Imaging is used as an adjunct to clinical staging for evaluation of nodal metastases. Fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) has an advantage of superior resolution of its CT component and detecting nodal disease based on increased glycolytic activity rather than node size. But there are limited studies describing its limitations in early stage cervical cancers. Objective: We have done meta-analysis with an objective to evaluate the efficacy of FDG PET/CT and its current clinical role in early stage and operable cervical cancer. Materials and Methods: Studies in which FDG PET/CT was performed before surgery in patients with early stage cervical cancers were included for analysis. PET findings were confirmed with histopathological diagnosis rather than clinical follow-up. FDG PET/CT showed lower sensitivity and clinically unacceptable negative predictive value in detecting nodal metastases in early stage cervical cancer and therefore, can not replace surgicopathological staging. False negative results in presence of microscopic disease and sub-centimeter diseased nodes are still the area of concern for metabolic imaging. However, these studies are single institutional and performed in a small group of patients. There is enough available evidence of clinical utility of FDG PET/CT in locally advanced cervical cancer. But these results can not be extrapolated for early stage disease. Conclusion: The current data suggest that FDG PET/CT is suboptimal in nodal staging in early stage cervical cancer. PMID:23559711

  17. Evaluation of the use of nodal methods for MTR neutronic analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Reitsma, F.; Mueller, E.Z.

    1997-08-01

    Although modern nodal methods are used extensively in the nuclear power industry, their use for research reactor analysis has been very limited. The suitability of nodal methods for material testing reactor analysis is investigated with the emphasis on the modelling of the core region (fuel assemblies). The nodal approach`s performance is compared with that of the traditional finite-difference fine mesh approach. The advantages of using nodal methods coupled with integrated cross section generation systems are highlighted, especially with respect to data preparation, simplicity of use and the possibility of performing a great variety of reactor calculations subject to strict timemore » limitations such as are required for the RERTR program.« less

  18. Nodal weighting factor method for ex-core fast neutron fluence evaluation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chiang, R. T.

    The nodal weighting factor method is developed for evaluating ex-core fast neutron flux in a nuclear reactor by utilizing adjoint neutron flux, a fictitious unit detector cross section for neutron energy above 1 or 0.1 MeV, the unit fission source, and relative assembly nodal powers. The method determines each nodal weighting factor for ex-core neutron fast flux evaluation by solving the steady-state adjoint neutron transport equation with a fictitious unit detector cross section for neutron energy above 1 or 0.1 MeV as the adjoint source, by integrating the unit fission source with a typical fission spectrum to the solved adjointmore » flux over all energies, all angles and given nodal volume, and by dividing it with the sum of all nodal weighting factors, which is a normalization factor. Then, the fast neutron flux can be obtained by summing the various relative nodal powers times the corresponding nodal weighting factors of the adjacent significantly contributed peripheral assembly nodes and times a proper fast neutron attenuation coefficient over an operating period. A generic set of nodal weighting factors can be used to evaluate neutron fluence at the same location for similar core design and fuel cycles, but the set of nodal weighting factors needs to be re-calibrated for a transition-fuel-cycle. This newly developed nodal weighting factor method should be a useful and simplified tool for evaluating fast neutron fluence at selected locations of interest in ex-core components of contemporary nuclear power reactors. (authors)« less

  19. Para-aortic nodal metastases in cervical cancer: a blind spot in the International Federation of Gynecology and Obstetrics staging system: current diagnosis and management.

    PubMed

    Hwang, Lindsay; Bailey, April; Lea, Jayanthi; Albuquerque, Kevin

    2015-01-01

    In cervical cancer, para-aortic nodal (PALN) metastases at presentation is a strong indicator of poor prognosis. Despite this, International Federation of Gynecology and Obstetrics staging system does not require evaluation of lymph node involvement and does not incorporate clinically detected PALN into the staging system. In the USA, despite screening, a significant number of women still present at an advanced stage often with nodal metastases. While the presence of PALN metastases often indicates occult systemic disease, it is possible with modern therapies to provide long-term control of disease in a percentage of patients. We review the epidemiology, diagnosis and treatment of PALN metastases in cervical cancer outlining advances in modern imaging and combined modality therapies (surgery, chemotherapy and radiation therapy).

  20. Meshfree Modeling of Munitions Penetration in Soils

    DTIC Science & Technology

    2017-04-01

    discretization ...................... 8 Figure 2. Nodal smoothing domain for the modified stabilized nonconforming nodal integration...projectile ............................................................................................... 36 Figure 17. Discretization for the...List of Acronyms DEM: discrete element methods FEM: finite element methods MSNNI: modified stabilized nonconforming nodal integration RK

  1. Targeting nodal in conjunction with dacarbazine induces synergistic anticancer effects in metastatic melanoma.

    PubMed

    Hardy, Katharine M; Strizzi, Luigi; Margaryan, Naira V; Gupta, Kanika; Murphy, George F; Scolyer, Richard A; Hendrix, Mary J C

    2015-04-01

    Metastatic melanoma is a highly aggressive skin cancer with a poor prognosis. Despite a complete response in fewer than 5% of patients, the chemotherapeutic agent dacarbazine (DTIC) remains the reference drug after almost 40 years. More recently, FDA-approved drugs have shown promise but patient outcome remains modest, predominantly due to drug resistance. As such, combinatorial targeting has received increased attention, and will advance with the identification of new molecular targets. One attractive target for improving melanoma therapy is the growth factor Nodal, whose normal expression is largely restricted to embryonic development, but is reactivated in metastatic melanoma. In this study, we sought to determine how Nodal-positive human melanoma cells respond to DTIC treatment and to ascertain whether targeting Nodal in combination with DTIC would be more effective than monotherapy. A single treatment with DTIC inhibited cell growth but did not induce apoptosis. Rather than reducing Nodal expression, DTIC increased the size of the Nodal-positive subpopulation, an observation coincident with increased cellular invasion. Importantly, clinical tissue specimens from patients with melanomas refractory to DTIC therapy stained positive for Nodal expression, both in pre- and post-DTIC tumors, underscoring the value of targeting Nodal. In vitro, anti-Nodal antibodies alone had some adverse effects on proliferation and apoptosis, but combining DTIC treatment with anti-Nodal antibodies decreased cell growth and increased apoptosis synergistically, at concentrations incapable of producing meaningful effects as monotherapy. Targeting Nodal in combination with DTIC therapy holds promise for the treatment of metastatic melanoma. ©2015 American Association for Cancer Research.

  2. Targeting Nodal in Conjunction with Dacarbazine Induces Synergistic Anti-cancer Effects in Metastatic Melanoma

    PubMed Central

    Hardy, Katharine M.; Strizzi, Luigi; Margaryan, Naira V.; Gupta, Kanika; Murphy, George F.; Scolyer, Richard A.; Hendrix, Mary J.C.

    2015-01-01

    Metastatic melanoma is a highly aggressive skin cancer with a poor prognosis. Despite a complete response in fewer than 5% of patients, the chemotherapeutic agent Dacarbazine (DTIC) remains the reference drug after almost 40 years. More recently FDA approved drugs have shown promise but patient outcome remains modest, predominantly due to drug resistance. As such, combinatorial targeting has received increased attention, and will advance with the identification of new molecular targets. One attractive target for improving melanoma therapy is the growth factor Nodal, whose normal expression is largely restricted to embryonic development, but is reactivated in metastatic melanoma. In this study, we sought to determine how Nodal-positive human melanoma cells respond to DTIC treatment and to ascertain if targeting Nodal in combination with DTIC would be more effective than monotherapy. A single treatment with DTIC inhibited cell growth but did not induce apoptosis. Rather than reducing Nodal expression, DTIC increased the size of the Nodal-positive subpopulation, an observation coincident with increased cellular invasion. Importantly, clinical tissue specimens from patients with melanomas refractory to DTIC therapy stained positive for Nodal expression, both in pre- and post-DTIC tumors, underscoring the value of targeting Nodal. In vitro, anti-Nodal antibodies alone had some adverse effects on proliferation and apoptosis, but combining DTIC treatment with anti-Nodal antibodies decreased cell growth and increased apoptosis synergistically, at concentrations incapable of producing meaningful effects as monotherapy. Implications Targeting Nodal in combination with DTIC therapy holds promise for the treatment of metastatic melanoma. PMID:25767211

  3. Intensity-modulated proton therapy for elective nodal irradiation and involved-field radiation in the definitive treatment of locally advanced non-small-cell lung cancer: a dosimetric study.

    PubMed

    Kesarwala, Aparna H; Ko, Christine J; Ning, Holly; Xanthopoulos, Eric; Haglund, Karl E; O'Meara, William P; Simone, Charles B; Rengan, Ramesh

    2015-05-01

    Photon involved-field (IF) radiation therapy (IFRT), the standard for locally advanced (LA) non-small cell lung cancer (NSCLC), results in favorable outcomes without increased isolated nodal failures, perhaps from scattered dose to elective nodal stations. Because of the high conformality of intensity-modulated proton therapy (IMPT), proton IFRT could increase nodal failures. We investigated the feasibility of IMPT for elective nodal irradiation (ENI) in LA-NSCLC. IMPT IFRT plans were generated to the same total dose of 66.6-72 Gy received by 20 LA-NSCLC patients treated with photon IFRT. IMPT ENI plans were generated to 46 cobalt Gray equivalent (CGE) to elective nodal planning treatment volumes (PTV) plus 24 CGE to IF-PTVs. Proton IFRT and ENI improved the IF-PTV percentage of volume receiving 95% of the prescribed dose (D95) by 4% (P < .01) compared with photon IFRT. All evaluated dosimetric parameters improved significantly with both proton plans. The lung percentage of volume receiving 20 Gy/CGE (V20) and mean lung dose decreased 18% (P < .01) and 36% (P < .01), respectively, with proton IFRT, and 11% (P = .03) and 26% (P < .01) with ENI. The mean esophagus dose decreased 16% with IFRT and 12% with ENI; heart V25 decreased 63% with both (all P < .01). This study demonstrates the feasibility of IMPT for LA-NSCLC ENI. Potential decreased toxicity indicates that IMPT could allow ENI while maintaining a favorable therapeutic ratio compared with photon IFRT. Published by Elsevier Inc.

  4. Pelvic Nodal Radiotherapy in Patients With Unfavorable Intermediate and High-Risk Prostate Cancer: Evidence, Rationale, and Future Directions

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Morikawa, Lisa K.; Memorial Sloan-Kettering Cancer Center; Roach, Mack, E-mail: mroach@radonc.ucsf.ed

    2011-05-01

    Over the past 15 years, there have been three major advances in the use of external beam radiotherapy in the management of men with clinically localized prostate made. They include: (1) image guided (IG) three-dimensional conformal/intensity modulated radiotherapy; (2) radiation dose escalation; and (3) androgen deprivation therapy. To date only the last of these three advances have been shown to improve overall survival. The presence of occult pelvic nodal involvement could explain the failure of increased conformality and dose escalation to prolong survival, because the men who appear to be at the greatest risk of death from clinically localized prostatemore » cancer are those who are likely to have lymph node metastases. This review discusses the evidence for prophylactic pelvic nodal radiotherapy, including the key trials and controversies surrounding this issue.« less

  5. Oestrogen receptors, nodes and stage as predictors of post-recurrence survival in 457 breast cancer patients.

    PubMed

    Shek, L L; Godolphin, W; Spinelli, J J

    1987-12-01

    The relationship to survival after first recurrence of oestrogen receptor (ER), nodal status and TNM stage at diagnosis, and treatment for advanced disease was studied in 457 females whose primary breast cancer was diagnosed in 1975 to 1981. Receptor concentration was the most important predictor of post-recurrence survival, with some additional information conveyed by nodal status. ER predicted survival after recurrence independently of nodal status, clinical stage or mode of therapy. Response to endocrine therapy is only a facet of the generally favourable prognosis of ER positive patients, rather than the sole explanation.

  6. Oestrogen receptors, nodes and stage as predictors of post-recurrence survival in 457 breast cancer patients.

    PubMed Central

    Shek, L. L.; Godolphin, W.; Spinelli, J. J.

    1987-01-01

    The relationship to survival after first recurrence of oestrogen receptor (ER), nodal status and TNM stage at diagnosis, and treatment for advanced disease was studied in 457 females whose primary breast cancer was diagnosed in 1975 to 1981. Receptor concentration was the most important predictor of post-recurrence survival, with some additional information conveyed by nodal status. ER predicted survival after recurrence independently of nodal status, clinical stage or mode of therapy. Response to endocrine therapy is only a facet of the generally favourable prognosis of ER positive patients, rather than the sole explanation. PMID:3435707

  7. Concurrent chemoradiotherapy with S-1 in patients with stage III-IV oral squamous cell carcinoma: A retrospective analysis of nodal classification based on the neck node level.

    PubMed

    Murakami, Ryuji; Semba, Akiko; Kawahara, Kenta; Matsuyama, Keiya; Hiraki, Akimitsu; Nagata, Masashi; Toya, Ryo; Yamashita, Yasuyuki; Oya, Natsuo; Nakayama, Hideki

    2017-07-01

    The aim of the present study was to retrospectively evaluate the treatment outcomes of concurrent chemoradiotherapy (CCRT) with S-1, an oral fluoropyrimidine anticancer agent, for advanced oral squamous cell carcinoma (SCC). The study population consisted of 47 patients with clinical stage III or IV oral SCC, who underwent CCRT with S-1. Pretreatment variables, including patient age, clinical stage, T classification, midline involvement of the primary tumor and nodal status, were analyzed as predictors of survival. In addition to the N classification (node-positive, multiple and contralateral), the prognostic impact of the level of nodal involvement was assessed. Nodal involvement was mainly observed at levels Ib and II; involvement at levels Ia and III-V was considered to be anterior and inferior extension, respectively, and was recorded as extensive nodal involvement (ENI). The 3-year overall survival (OS) and progression-free survival (PFS) rates were 37 and 27%, respectively. A finding of ENI was a significant factor for OS [hazard ratio (HR)=2.16; 95% confidence interval (CI): 1.03-4.55; P=0.038] and PFS (HR=2.65; 95% CI: 1.32-5.33; P=0.005); the 3-year OS and PFS rates in patients with vs. those without ENI were 23 vs. 50% and 9 vs. 43%, respectively. The other variables were not significant. Therefore, CCRT with S-1 may be an alternative treatment for advanced oral SCC; favorable outcomes are expected in patients without ENI.

  8. Risk of isolated nodal failure for non-small cell lung cancer (NSCLC) treated with the elective nodal irradiation (ENI) using 3D-conformal radiotherapy (3D-CRT) techniques--a retrospective analysis.

    PubMed

    Kepka, Lucyna; Bujko, Krzysztof; Zolciak-Siwinska, Agnieszka

    2008-01-01

    To estimate retrospectively the rate of isolated nodal failures (INF) in NSCLC patients treated with the elective nodal irradiation (ENI) using 3D-conformal radiotherapy (3D-CRT). One hundred and eighty-five patients with I-IIIB stage treated with 3D-CRT in consecutive clinical trials differing in an extent of the ENI were analyzed. According to the extent of the ENI, two groups were distinguished: extended (n = 124) and limited (n = 61) ENI. INF was defined as regional nodal failure occurring without local progression. Cumulative Incidence of INF (CIINF) was evaluated by univariate and multivariate analysis with regard to prognostic factors. With a median follow up of 30 months, the two-year actuarial overall survival was 35%. The two-year CIINF rate was 12%. There were 16 (9%) INF, eight (6%) for extended and eight (13%) for limited ENI. In the univariate analysis bulky mediastinal disease (BMD), left side, higher N stage, and partial response to RT had a significant negative impact on the CIINF. BMD was the only independent predictor of the risk of incidence of the INF (p = 0.001). INF is more likely to occur in case of more advanced nodal status.

  9. Threes company

    NASA Astrophysics Data System (ADS)

    Wieder, Benjamin J.

    2018-04-01

    Enabled by recent advances in symmetry and electronic structure, researchers have observed signatures of unconventional threefold degeneracies in tungsten carbide, challenging a longstanding paradigm in nodal semimetals.

  10. Adaptive Nodal Transport Methods for Reactor Transient Analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Thomas Downar; E. Lewis

    2005-08-31

    Develop methods for adaptively treating the angular, spatial, and time dependence of the neutron flux in reactor transient analysis. These methods were demonstrated in the DOE transport nodal code VARIANT and the US NRC spatial kinetics code, PARCS.

  11. On the Viability of Using Autonomous Three-Component Nodal Geophones to Calculate Teleseismic Ps Receiver Functions with an Application to the Old Faithful Hydrothermal System and the Cascadia Subduction Zone

    NASA Astrophysics Data System (ADS)

    Ward, K. M.; Lin, F. C.

    2017-12-01

    Recent advances in seismic data-acquisition technology paired with an increasing interest from the academic passive source seismological community have opened up new scientific targets and imaging possibilities, often referred to as Large-N experiments (large number of instruments). The success of these and other deployments has motivated individual researchers, as well as the larger seismological community, to invest in the next generation of nodal geophones. Although the new instruments have battery life and bandwidth limitations compared to broadband instruments, the relatively low deployment and procurement cost of these new nodal geophones provides an additional novel tool for researchers. Here, we explore the viability of using autonomous three-component nodal geophones to calculate teleseismic Ps receiver functions by comparison of co-located broadband stations and highlight some potential advantages with a dense nodal array deployed around the Upper Geyser basin in Yellowstone National Park. Two key findings from this example include (1) very dense nodal arrays can be used to image small-scale features in the shallow crust that typical broadband station spacing would alias, and (2) nodal arrays with a larger footprint could be used to image deeper features with greater or equal detail as typical broadband deployments but at a reduced deployment cost. The success of the previous example has motivated a larger 2-D line across the Cascadia subduction zone. In the summer of 2017, we deployed 174 nodal geophones with an average site spacing of 750 m. Synthetic tests with dense station spacing ( 1 km) reveal subtler features of the system that is consistent with our preliminary receiver function results from our Cascadia deployment. With the increasing availability of nodal geophones to individual researchers and the successful demonstration that nodal geophones are a viable instrument for receiver function studies, numerous scientific targets can be investigated at reduced costs or in expanded detail.

  12. Risk of Subclinical Micrometastatic Disease in the Supraclavicular Nodal Bed According to the Anatomic Distribution in Patients With Advanced Breast Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Reed, Valerie K.; Cavalcanti, Jose L.; Strom, Eric A.

    Purpose: To determine the anatomic distribution of gross supraclavicular nodes within the supraclavicular fossa using 2-deoxy-2-[F-18] fluoro-d-glucose (FDG) positron emission tomography/computed tomography (PET/CT) scans, and to evaluate likely coverage of specific regions of the supraclavicular fossa using standard radiation fields. Methods and Materials: We identified 33 patients with advanced or metastatic breast cancer who had a PET/CT scan demonstrating hypermetabolic supraclavicular lymph nodes in 2005. The locations of the involved lymph nodes were mapped onto a single CT set of images of the supraclavicular fossa. These lymph nodes were also mapped onto the treatment-planning CT dataset of 4 patients treatedmore » in our institution (2 patients with biopsy-proven supraclavicular nodes and 2 patients with clinically negative supraclavicular nodes). Results: We were able to determine the distribution of 52 supraclavicular lymph nodes in 32 patients. Of 32 patients, 28 (87%) had a history of metastatic disease, and 2 patients had isolated nodal recurrences. Five patients had supraclavicular nodes posterior to the vertebral body transverse process, and several lymph nodes were in close proximity to the medial field border, raising the possibility of geographic miss in these areas. Conclusions: In patients with locally advanced disease, increased coverage of the supraclavicular fossa medially and posteriorly may be warranted.« less

  13. The value of nodal information in predicting lung cancer relapse using 4DPET/4DCT

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Heyse, E-mail: heyse.li@mail.utoronto.ca; Becker, Nathan; Raman, Srinivas

    2015-08-15

    Purpose: There is evidence that computed tomography (CT) and positron emission tomography (PET) imaging metrics are prognostic and predictive in nonsmall cell lung cancer (NSCLC) treatment outcomes. However, few studies have explored the use of standardized uptake value (SUV)-based image features of nodal regions as predictive features. The authors investigated and compared the use of tumor and node image features extracted from the radiotherapy target volumes to predict relapse in a cohort of NSCLC patients undergoing chemoradiation treatment. Methods: A prospective cohort of 25 patients with locally advanced NSCLC underwent 4DPET/4DCT imaging for radiation planning. Thirty-seven image features were derivedmore » from the CT-defined volumes and SUVs of the PET image from both the tumor and nodal target regions. The machine learning methods of logistic regression and repeated stratified five-fold cross-validation (CV) were used to predict local and overall relapses in 2 yr. The authors used well-known feature selection methods (Spearman’s rank correlation, recursive feature elimination) within each fold of CV. Classifiers were ranked on their Matthew’s correlation coefficient (MCC) after CV. Area under the curve, sensitivity, and specificity values are also presented. Results: For predicting local relapse, the best classifier found had a mean MCC of 0.07 and was composed of eight tumor features. For predicting overall relapse, the best classifier found had a mean MCC of 0.29 and was composed of a single feature: the volume greater than 0.5 times the maximum SUV (N). Conclusions: The best classifier for predicting local relapse had only tumor features. In contrast, the best classifier for predicting overall relapse included a node feature. Overall, the methods showed that nodes add value in predicting overall relapse but not local relapse.« less

  14. Development of a Robust and Cost-Effective Friction Stir Welding Process for Use in Advanced Military Vehicles

    DTIC Science & Technology

    2011-01-01

    aluminum alloys, as well 81 as aluminum matrix composites can be readily FSWed; 82 (j) due to lower attendant temperatures, the residual stres - 83 ses... role of the precipitation hardening mechanism in heat- 372treatable alloys is concerned, the following main observations 373can be made. Typically in...stirring/mixing 470(which plays a critical role in weld quality/joint-strength) is 471increased. 472Nodal Velocity Field. The distribution of nodal

  15. Comparison of Toxicity Between Intensity-Modulated Radiotherapy and 3-Dimensional Conformal Radiotherapy for Locally Advanced Non-small-cell Lung Cancer.

    PubMed

    Ling, Diane C; Hess, Clayton B; Chen, Allen M; Daly, Megan E

    2016-01-01

    The role of intensity-modulated radiotherapy (IMRT) in reducing treatment-related toxicity for locally advanced non-small-cell lung cancer (NSCLC) remains incompletely defined. We compared acute toxicity and oncologic outcomes in a large cohort of patients treated with IMRT or 3-dimensional conformal radiotherapy (3-DCRT), with or without elective nodal irradiation (ENI). A single-institution retrospective review was performed evaluating 145 consecutive patients with histologically confirmed stage III NSCLC treated with definitive chemoradiotherapy. Sixty-five (44.8%) were treated with 3-DCRT using ENI, 43 (30.0%) with 3-DCRT using involved-field radiotherapy (IFRT), and 37 (25.5%) with IMRT using IFRT. All patients received concurrent chemotherapy. Comparison of acute toxicities by treatment technique (IMRT vs. 3-DCRT) and extent of nodal irradiation (3-DCRT-IFRT vs. 3-DCRT-ENI) was performed for grade 2 or higher esophagitis or pneumonitis, number of acute hospitalizations, incidence of opioid requirement, percutaneous endoscopic gastrostomy utilization, and percentage weight loss during treatment. Local control and overall survival were analyzed by the Kaplan-Meier method. We identified no significant differences in any measures of acute toxicity by treatment technique or extent of nodal irradiation. There was a trend toward lower rates of grade 2 or higher pneumonitis among IMRT patients compared to 3-DCRT patients (5.4% vs. 23.0%; P = .065). Local control and overall survival were similar between cohorts. Acute and subacute toxicities were similar for patients treated with IMRT and with 3-DCRT with or without ENI, with a nonsignificant trend toward a reduction in pneumonitis with IMRT. Larger studies are needed to better define which patients will benefit from IMRT. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Reactivation of Embryonic Nodal Signaling is Associated with Tumor Progression and Promotes the Growth of Prostate Cancer Cells

    PubMed Central

    Lawrence, Mitchell G.; Margaryan, Naira V.; Loessner, Daniela; Collins, Angus; Kerr, Kris M.; Turner, Megan; Seftor, Elisabeth A.; Stephens, Carson R.; Lai, John; BioResource, APC; Postovit, Lynne-Marie; Clements, Judith A.; Hendrix, Mary J.C.

    2011-01-01

    Background Nodal is a member of the Transforming Growth Factor β (TGFβ) superfamily that directs embryonic patterning and promotes the plasticity and tumorigenicity of tumor cells, but its role in the prostate is unknown. The goal of this study was to characterize the expression and function of Nodal in prostate cancer and determine whether, like other TGFβ ligands, it modulates androgen receptor (AR) activity. Methods Nodal expression was investigated using immunohistochemistry of tissue microarrays and Western blots of prostate cell lines. The functional role of Nodal was examined using Matrigel and soft agar growth assays. Cross-talk between Nodal and AR signaling was assessed with luciferase reporter assays and expression of endogenous androgen regulated genes. Results Significantly increased Nodal expression was observed in cancer compared with benign prostate specimens. Nodal was only expressed by DU145 and PC3 cells. All cell lines expressed Nodal’s co-receptor, Cripto-1, but lacked Lefty, a critical negative regulator of Nodal signaling. Recombinant human Nodal triggered downstream Smad2 phosphorylation in DU145 and LNCaP cells, and stable transfection of pre-pro-Nodal enhanced the growth of LNCaP cells in Matrigel and soft agar. Finally, Nodal attenuated AR signaling, reducing the activity of a PSA promoter construct in luciferase assays and down-regulating the endogenous expression of androgen regulated genes. Conclusions An aberrant Nodal signaling pathway is re-expressed and functionally active in prostate cancer cells. PMID:21656830

  17. Dose-volume effects in pathologic lymph nodes in locally advanced cervical cancer.

    PubMed

    Bacorro, Warren; Dumas, Isabelle; Escande, Alexandre; Gouy, Sebastien; Bentivegna, Enrica; Morice, Philippe; Haie-Meder, Christine; Chargari, Cyrus

    2018-03-01

    In cervical cancer patients, dose-volume relationships have been demonstrated for tumor and organs-at-risk, but not for pathologic nodes. The nodal control probability (NCP) according to dose/volume parameters was investigated. Patients with node-positive cervical cancer treated curatively with external beam radiotherapy (EBRT) and image-guided brachytherapy (IGABT) were identified. Nodal doses during EBRT, IGABT and boost were converted to 2-Gy equivalent (α/β = 10 Gy) and summed. Pathologic nodes were followed individually from diagnosis to relapse. Statistical analyses comprised log-rank tests (univariate analyses), Cox proportional model (factors with p ≤ 0.1 in univariate) and Probit analyses. A total of 108 patients with 254 unresected pathological nodes were identified. The mean nodal volume at diagnosis was 3.4 ± 5.8 cm 3 . The mean total nodal EQD2 doses were 55.3 ± 5.6 Gy. Concurrent chemotherapy was given in 96%. With a median follow-up of 33.5 months, 20 patients (18.5%) experienced relapse in nodes considered pathologic at diagnosis. Overall nodal recurrence rate was 9.1% (23/254). On univariate analyses, nodal volume (threshold: 3 cm 3 , p < .0001) and lymph node dose (≥57.5 Gy α/β10 , p = .039) were significant for nodal control. The use of simultaneous boost was borderline for significance (p = .07). On multivariate analysis, volume (HR = 8.2, 4.0-16.6, p < .0001) and dose (HR = 2, 1.05-3.9, p = .034) remained independent factors. Probit analysis combining dose and volume showed significant relationships with NCP, with increasing gap between the curves with higher nodal volumes. A nodal dose-volume effect on NCP is demonstrated for the first time, with increasing NCP benefit of additional doses to higher-volume nodes. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. A forward-advancing wave expansion method for numerical solution of large-scale sound propagation problems

    NASA Astrophysics Data System (ADS)

    Rolla, L. Barrera; Rice, H. J.

    2006-09-01

    In this paper a "forward-advancing" field discretization method suitable for solving the Helmholtz equation in large-scale problems is proposed. The forward wave expansion method (FWEM) is derived from a highly efficient discretization procedure based on interpolation of wave functions known as the wave expansion method (WEM). The FWEM computes the propagated sound field by means of an exclusively forward advancing solution, neglecting the backscattered field. It is thus analogous to methods such as the (one way) parabolic equation method (PEM) (usually discretized using standard finite difference or finite element methods). These techniques do not require the inversion of large system matrices and thus enable the solution of large-scale acoustic problems where backscatter is not of interest. Calculations using FWEM are presented for two propagation problems and comparisons to data computed with analytical and theoretical solutions and show this forward approximation to be highly accurate. Examples of sound propagation over a screen in upwind and downwind refracting atmospheric conditions at low nodal spacings (0.2 per wavelength in the propagation direction) are also included to demonstrate the flexibility and efficiency of the method.

  19. Long-term outcome of ultrasound-guided percutaneous ethanol ablation of selected "recurrent" neck nodal metastases in 25 patients with TNM stages III or IVA papillary thyroid carcinoma previously treated by surgery and 131I therapy.

    PubMed

    Hay, Ian D; Lee, Robert A; Davidge-Pitts, Caroline; Reading, Carl C; Charboneau, J William

    2013-12-01

    Ultrasound-guided percutaneous ethanol ablation (UPEA) of neck nodal metastases (NNM) has rarely been reported in papillary thyroid carcinoma (PTC) patients with advanced localized disease. We ablated 25 PTC patients with stage III or IVA disease (mean age 58 years) who had "recurrent" NNM after surgery and 131I therapy. Diagnosis of 37 selected NNM was proven by ultrasound-guided biopsy. UPEA was usually performed in 2 outpatient sessions. After UPEA, 35 of 37 NNM (95%) decreased in size. None had significant Doppler flow. Seventeen (46%) disappeared on rescanning. Serum thyroglobulin fell in 19 of 22 (86%) without thyroglobulin autoantibodies. None of the UPEA-treated NNM, followed on average for 5.4 years, required further intervention. Six patients (24%) subsequently developed 18 "new" recurrences. Of the 18, 15 (83%) were managed successfully by UPEA rather than operation. None of the 25 patients developed permanent hoarseness or have died from PTC. At our institution, where patients undergoing nodal dissections are charged $35-45,000, each outpatient UPEA procedure saves health providers approximately $38,400. Our 25 ablated patients, by avoiding 40 further neck reexplorations, on average, saved $61,440 in charges. UPEA for NNM in advanced localized PTC has proved safe and effective. It is also considerably less expensive than the conventional operative alternative of nodal dissection. Copyright © 2013 Mosby, Inc. All rights reserved.

  20. Involved field radiotherapy (IFRT) versus elective nodal irradiation (ENI) for locally advanced non-small cell lung cancer: a meta-analysis of incidence of elective nodal failure (ENF).

    PubMed

    Li, Ruijian; Yu, Liang; Lin, Sixiang; Wang, Lina; Dong, Xin; Yu, Lingxia; Li, Weiyi; Li, Baosheng

    2016-09-21

    The use of involved field radiotherapy (IFRT) has generated concern about the increasing incidence of elective nodal failure (ENF) in contrast to elective nodal irradiation (ENI). This meta-analysis aimed to provide more reliable and up-to-date evidence on the incidence of ENF between IFRT and ENI. We searched three databases for eligible studies where locally advanced non-small cell lung cancer (NSCLC) patients received IFRT or ENI. Outcome of interest was the incidence of ENF. The fixed-effects model was used to pool outcomes across the studies. There were 3 RCTs and 3 cohort studies included with low risk of bias. There was no significant difference in incidence of ENF between IFRT and ENI either among RCTs (RR = 1.38, 95 % CI: 0.59-3.25, p = 0.46) or among cohort studies (RR = 0.99, 95 % CI: 0.46-2.10, p = 0.97). There was also no significant difference in incidence of ENF between IFRT and ENI when RCTs and cohort studies were combined (RR = 1.15, 95 % CI: 0.65-2.01, p = 0.64). I 2 of test for heterogeneity was 0 %. This meta-analysis provides more reliable and stable evidence that there is no significant difference in incidence of ENF between IFRT and ENI.

  1. Nodal Analysis Optimization Based on the Use of Virtual Current Sources: A Powerful New Pedagogical Method

    ERIC Educational Resources Information Center

    Chatzarakis, G. E.

    2009-01-01

    This paper presents a new pedagogical method for nodal analysis optimization based on the use of virtual current sources, applicable to any linear electric circuit (LEC), regardless of its complexity. The proposed method leads to straightforward solutions, mostly arrived at by inspection. Furthermore, the method is easily adapted to computer…

  2. A weak Hamiltonian finite element method for optimal guidance of an advanced launch vehicle

    NASA Technical Reports Server (NTRS)

    Hodges, Dewey H.; Calise, Anthony J.; Bless, Robert R.; Leung, Martin

    1989-01-01

    A temporal finite-element method based on a mixed form of the Hamiltonian weak principle is presented for optimal control problems. The mixed form of this principle contains both states and costates as primary variables, which are expanded in terms of nodal values and simple shape functions. Time derivatives of the states and costates do not appear in the governing variational equation; the only quantities whose time derivatives appear therein are virtual states and virtual costates. Numerical results are presented for an elementary trajectory optimization problem; they show very good agreement with the exact solution along with excellent computational efficiency and self-starting capability. The feasibility of this approach for real-time guidance applications is evaluated. A simplified model for an advanced launch vehicle application that is suitable for finite-element solution is presented.

  3. A point-value enhanced finite volume method based on approximate delta functions

    NASA Astrophysics Data System (ADS)

    Xuan, Li-Jun; Majdalani, Joseph

    2018-02-01

    We revisit the concept of an approximate delta function (ADF), introduced by Huynh (2011) [1], in the form of a finite-order polynomial that holds identical integral properties to the Dirac delta function when used in conjunction with a finite-order polynomial integrand over a finite domain. We show that the use of generic ADF polynomials can be effective at recovering and generalizing several high-order methods, including Taylor-based and nodal-based Discontinuous Galerkin methods, as well as the Correction Procedure via Reconstruction. Based on the ADF concept, we then proceed to formulate a Point-value enhanced Finite Volume (PFV) method, which stores and updates the cell-averaged values inside each element as well as the unknown quantities and, if needed, their derivatives on nodal points. The sharing of nodal information with surrounding elements saves the number of degrees of freedom compared to other compact methods at the same order. To ensure conservation, cell-averaged values are updated using an identical approach to that adopted in the finite volume method. Here, the updating of nodal values and their derivatives is achieved through an ADF concept that leverages all of the elements within the domain of integration that share the same nodal point. The resulting scheme is shown to be very stable at successively increasing orders. Both accuracy and stability of the PFV method are verified using a Fourier analysis and through applications to the linear wave and nonlinear Burgers' equations in one-dimensional space.

  4. Face Centered Cubic SnSe as a Z2 Trivial Dirac Nodal Line Material

    NASA Astrophysics Data System (ADS)

    Tateishi, Ikuma; Matsuura, Hiroyasu

    2018-07-01

    The presence of a Dirac nodal line in a time-reversal and inversion symmetric system is dictated by the Z2 index when spin-orbit interaction is absent. In a first principles calculation, we show that a Dirac nodal line can emerge in Z2 trivial material by calculating the band structure of SnSe in a face centered cubic lattice as an example. We qualitatively show that it becomes a topological crystalline insulator when spin-orbit interaction is taken into account. We clarify the origin of the Dirac nodal line by obtaining irreducible representations corresponding to bands and explain the triviality of the Z2 index. We construct an effective model representing the Dirac nodal line using the k · p method, and discuss the Berry phase and a surface state expected from the Dirac nodal line.

  5. Treatment outcomes in locally advanced colorectal carcinoma

    PubMed Central

    Harish, K; Narayanaswamy, YV; Nirmala, S

    2004-01-01

    Background Locally advanced colorectal cancers form a distinct subgroup where contiguous organs could be involved without distant metastases and so may be amenable to curative surgical resection. It was our objective to report our experience in treating six such patients with operable locally advanced colorectal carcinomas. Methods We retrospectively reviewed the case notes of 47 patients who were diagnosed with colorectal cancers at M S Ramaiah Medical Teaching Hospital between the years 1996 – 2001. Six patients were identified with T4 lesions, adjacent organ involvement and with no nodal involvement. The treatments and outcomes for these patients were then reviewed. Results Two of three patients with rectal malignancies who underwent pelvic exenteration succumbed to disease recurrence within the first 18 months. One of the three patients with colonic cancers died of non malignant causes. The other two are disease free till date. Conclusions Aggressive multivisceral resections for locally advanced colonic cancers might be appropriate. Rectal cancers when locally advanced may be considered for pelvic exenteration, but a more guarded prognosis may apply. PMID:15527504

  6. Neoadjuvant oral vs. infusional chemoradiotherapy on locally advanced rectal cancer: Prognostic factors.

    PubMed

    Conde, Sofia; Borrego, Margarida; Teixeira, Tânia; Teixeira, Rubina; Sá, Anabela; Soares, Paula

    2012-01-01

    To evaluate the prognostic factors and impact on survival of neoadjuvant oral and infusional chemoradiotherapy in patients with locally advanced rectal cancer. There is still no definitive consensus about the prognostic factors and the impact of neoadjuvant chemoradiotherapy on survival. Some studies have pointed to an improvement in overall survival (OS) and progression-free survival (PFS) in patients with tumor downstaging (TD) and nodal downstaging (ND). A set of 159 patients with LARC were treated preoperatively. Group A - 112 patients underwent concomitant oral chemoradiotherapy: capecitabine or UFT + folinic acid. Group B - 47 patients submitted to concomitant chemoradiation with 5-FU in continuous infusion. 63.6% of patients were submitted to adjuvant chemotherapy. pathologic complete response (pCR) - 18.7%; TD - 55.1%; ND - 76%; loco-regional response - 74.8%. Group B: pCR - 11.4%; TD - 50%; ND - 55.8%; LRR - 54.5%. The loco-regional control was 95.6%. There was no difference in survival between both groups. Those with loco-regional response had better PFS. Tumor and nodal downstaging, loco-regional response and a normal CEA level turned out to be important prognostic factors in locally advanced rectal cancer. Nodal downstaging and loco-regional response were higher in Group A. Those with tumor downstaging and loco-regional response from Group A had better OS. Adjuvant chemotherapy had no impact on survival except in those patients with loco-regional response who achieved a higher PFS.

  7. Type-I and type-II topological nodal superconductors with s -wave interaction

    NASA Astrophysics Data System (ADS)

    Huang, Beibing; Yang, Xiaosen; Xu, Ning; Gong, Ming

    2018-01-01

    Topological nodal superconductors with protected gapless points in momentum space are generally realized based on unconventional pairings. In this work we propose a minimal model to realize these topological nodal phases with only s -wave interaction. In our model the linear and quadratic spin-orbit couplings along the two orthogonal directions introduce anisotropic effective unconventional pairings in momentum space. This model may support different nodal superconducting phases characterized by either an integer winding number in BDI class or a Z2 index in D class at the particle-hole invariant axes. In the vicinity of the nodal points the effective Hamiltonian can be described by either type-I or type-II Dirac equations, and the Lifshitz transition from type-I nodal phases to type-II nodal phases can be driven by external in-plane magnetic fields. We show that these nodal phases are robust against weak impurities, which only slightly renormalizes the momentum-independent parameters in the impurity-averaged Hamiltonian, thus these phases are possible to be realized in experiments with real semi-Dirac materials. The smoking-gun evidences to verify these phases based on scanning tunneling spectroscopy method are also briefly discussed.

  8. Human papillomavirus reduces the prognostic value of nodal involvement in tonsillar squamous cell carcinomas.

    PubMed

    Straetmans, Jos M J A A; Olthof, Nadine; Mooren, Jeroen J; de Jong, Jos; Speel, Ernst-Jan M; Kremer, Bernd

    2009-10-01

    Assessment of the prognostic value of nodal status in relation to human papillomavirus (HPV) status and the various treatment modalities in tonsillar squamous cell carcinomas (TSCC). Retrospective 5-year survival analysis. A 5-year follow-up of disease-free, disease-specific, and overall survival in a group of 81 patients with TSCC was conducted. The nodal status and integration of HPV-DNA in the genome (detected with fluorescence in situ hybridization) as prognostic indicators were examined while correcting for other clinical parameters (smoking habits, alcohol consumption, treatment modality, differentiation, TNM classification). Of TSCCs, 41% were positive for HPV type 16. In these TSCCs, the primary tumor was significantly smaller when compared to HVP-negative TSCCs (P = .04), whereas the percentage of cases with cervical metastases was identical. In the total population, it was not nodal involvement, but rather HPV manifestation, which was related to patient prognosis. Within the treatment modalities (surgery combined with radiotherapy and radiotherapy alone), neither nodal status nor HPV were prognostic indicators. Since a substantial percentage of TSCCs are HPV-positive and metastasizes to cervical lymph nodes in less advanced primary tumors, the N status is an unreliable prognostic indicator in TSCCs. HPV is only prognostically relevant in the total tumor population, but loses its value within patient groups receiving a single treatment modality. The value of HPV for prognosis of patients with TSCC requires further study.

  9. Methods, safety, and early clinical outcomes of dose escalation using simultaneous integrated and sequential boosts in patients with locally advanced gynecologic malignancies.

    PubMed

    Boyle, John; Craciunescu, Oana; Steffey, Beverly; Cai, Jing; Chino, Junzo

    2014-11-01

    To evaluate the safety of dose escalated radiotherapy using a simultaneous integrated boost technique in patients with locally advanced gynecological malignancies. Thirty-nine women with locally advanced gynecological malignancies were treated with intensity modulated radiation therapy utilizing a simultaneous integrated boost (SIB) technique for gross disease in the para-aortic and/or pelvic nodal basins, sidewall extension, or residual primary disease. Women were treated to 45Gy in 1.8Gy fractions to elective nodal regions. Gross disease was simultaneously treated to 55Gy in 2.2Gy fractions (n=44 sites). An additional sequential boost of 10Gy in 2Gy fractions was delivered if deemed appropriate (n=29 sites). Acute and late toxicity, local control in the treated volumes (LC), overall survival (OS), and distant metastases (DM) were assessed. All were treated with a SIB to a dose of 55Gy. Twenty-four patients were subsequently treated with a sequential boost to a median dose of 65Gy. Median follow-up was 18months. Rates of acute>grade 2 gastrointestinal (GI), genitourinary (GU), and hematologic (heme) toxicities were 2.5%, 0%, and 30%, respectively. There were no grade 4 acute toxicities. At one year, grade 1-2 late GI toxicities were 24.5%. There were no grade 3 or 4 late GI toxicities. Rates of grade 1-2 late GU toxicities were 12.7%. There were no grade 3 or 4 late GU toxicities. Dose escalated radiotherapy using a SIB results in acceptable rates of acute toxicity. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Response of millet and sorghum to a varying water supply around the primary and nodal roots

    PubMed Central

    Rostamza, M.; Richards, R. A.; Watt, M.

    2013-01-01

    Background and Aims Cereals have two root systems. The primary system originates from the embryo when the seed germinates and can support the plant until it produces grain. The nodal system can emerge from stem nodes throughout the plant's life; its value for yield is unclear and depends on the environment. The aim of this study was to test the role of nodal roots of sorghum and millet in plant growth in response to variation in soil moisture. Sorghum and millet were chosen as both are adapted to dry conditions. Methods Sorghum and millet were grown in a split-pot system that allowed the primary and nodal roots to be watered separately. Key Results When primary and nodal roots were watered (12 % soil water content; SWC), millet nodal roots were seven times longer than those of sorghum and six times longer than millet plants in dry treatments, mainly from an 8-fold increase in branch root length. When soil was allowed to dry in both compartments, millet nodal roots responded and grew 20 % longer branch roots than in the well-watered control. Sorghum nodal roots were unchanged. When only primary roots received water, nodal roots of both species emerged and elongated into extremely dry soil (0·6–1·5 % SWC), possibly with phloem-delivered water from the primary roots in the moist inner pot. Nodal roots were thick, short, branchless and vertical, indicating a tropism that was more pronounced in millet. Total nodal root length increased in both species when the dry soil was covered with plastic, suggesting that stubble retention or leaf mulching could facilitate nodal roots reaching deeper moist layers in dry climates. Greater nodal root length in millet than in sorghum was associated with increased shoot biomass, water uptake and water use efficiency (shoot mass per water). Millet had a more plastic response than sorghum to moisture around the nodal roots due to (1) faster growth and progression through ontogeny for earlier nodal root branch length and (2) partitioning to nodal root length from primary roots, independent of shoot size. Conclusions Nodal and primary roots have distinct responses to soil moisture that depend on species. They can be selected independently in a breeding programme to shape root architecture. A rapid rate of plant development and enhanced responsiveness to local moisture may be traits that favour nodal roots and water use efficiency at no cost to shoot growth. PMID:23749473

  11. Interface projection techniques for fluid-structure interaction modeling with moving-mesh methods

    NASA Astrophysics Data System (ADS)

    Tezduyar, Tayfun E.; Sathe, Sunil; Pausewang, Jason; Schwaab, Matthew; Christopher, Jason; Crabtree, Jason

    2008-12-01

    The stabilized space-time fluid-structure interaction (SSTFSI) technique developed by the Team for Advanced Flow Simulation and Modeling (T★AFSM) was applied to a number of 3D examples, including arterial fluid mechanics and parachute aerodynamics. Here we focus on the interface projection techniques that were developed as supplementary methods targeting the computational challenges associated with the geometric complexities of the fluid-structure interface. Although these supplementary techniques were developed in conjunction with the SSTFSI method and in the context of air-fabric interactions, they can also be used in conjunction with other moving-mesh methods, such as the Arbitrary Lagrangian-Eulerian (ALE) method, and in the context of other classes of FSI applications. The supplementary techniques currently consist of using split nodal values for pressure at the edges of the fabric and incompatible meshes at the air-fabric interfaces, the FSI Geometric Smoothing Technique (FSI-GST), and the Homogenized Modeling of Geometric Porosity (HMGP). Using split nodal values for pressure at the edges and incompatible meshes at the interfaces stabilizes the structural response at the edges of the membrane used in modeling the fabric. With the FSI-GST, the fluid mechanics mesh is sheltered from the consequences of the geometric complexity of the structure. With the HMGP, we bypass the intractable complexities of the geometric porosity by approximating it with an “equivalent”, locally-varying fabric porosity. As test cases demonstrating how the interface projection techniques work, we compute the air-fabric interactions of windsocks, sails and ringsail parachutes.

  12. Finite-analytic numerical solution of heat transfer in two-dimensional cavity flow

    NASA Technical Reports Server (NTRS)

    Chen, C.-J.; Naseri-Neshat, H.; Ho, K.-S.

    1981-01-01

    Heat transfer in cavity flow is numerically analyzed by a new numerical method called the finite-analytic method. The basic idea of the finite-analytic method is the incorporation of local analytic solutions in the numerical solutions of linear or nonlinear partial differential equations. In the present investigation, the local analytic solutions for temperature, stream function, and vorticity distributions are derived. When the local analytic solution is evaluated at a given nodal point, it gives an algebraic relationship between a nodal value in a subregion and its neighboring nodal points. A system of algebraic equations is solved to provide the numerical solution of the problem. The finite-analytic method is used to solve heat transfer in the cavity flow at high Reynolds number (1000) for Prandtl numbers of 0.1, 1, and 10.

  13. Nodal Green’s Function Method Singular Source Term and Burnable Poison Treatment in Hexagonal Geometry

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    A.A. Bingham; R.M. Ferrer; A.M. ougouag

    2009-09-01

    An accurate and computationally efficient two or three-dimensional neutron diffusion model will be necessary for the development, safety parameters computation, and fuel cycle analysis of a prismatic Very High Temperature Reactor (VHTR) design under Next Generation Nuclear Plant Project (NGNP). For this purpose, an analytical nodal Green’s function solution for the transverse integrated neutron diffusion equation is developed in two and three-dimensional hexagonal geometry. This scheme is incorporated into HEXPEDITE, a code first developed by Fitzpatrick and Ougouag. HEXPEDITE neglects non-physical discontinuity terms that arise in the transverse leakage due to the transverse integration procedure application to hexagonal geometry andmore » cannot account for the effects of burnable poisons across nodal boundaries. The test code being developed for this document accounts for these terms by maintaining an inventory of neutrons by using the nodal balance equation as a constraint of the neutron flux equation. The method developed in this report is intended to restore neutron conservation and increase the accuracy of the code by adding these terms to the transverse integrated flux solution and applying the nodal Green’s function solution to the resulting equation to derive a semi-analytical solution.« less

  14. Rapid enhancement of nodal quasiparticle mass with heavily underdoping in Bi2212

    NASA Astrophysics Data System (ADS)

    Anzai, Hiroaki; Arita, Masashi; Namatame, Hirofumi; Taniguchi, Masaki; Ishikado, Motoyuki; Fujita, Kazuhiro; Ishida, Shigeyuki; Uchida, Shin-ichi; Ino, Akihiro

    2018-05-01

    We report substantial advance of our low-energy angle-resolved photoemission study of nodal quasiparticles in Bi2Sr2CaCu2O8+δ. The new data cover the samples from underdoped down to heavily underdoped levels. We also present the nodal Fermi velocities that determined by using an excitation-photon energy of hν = 7.0 eV over a wide doping range. The consistency between the results with hν = 8.1 and 7.0 eV allows us to rule out the effect of photoemission matrix elements. In comparison with the data previously reported, the nodal effective mass increases by a factor of ∼ 1.5 in going from optimally doped to heavily underdoped levels. We find a rapid enhancement of the nodal quasiparticle mass at low doping levels near the superconductor-to-insulator transition. The effective coupling spectrum, λ (ω) , is extracted directly from the energy derivatives of the quasiparticle dispersion and scattering rate, as a causal function of the mass enhancement factor. A steplike increase in Reλ (ω) around ∼ 65 meV is demonstrated clearly by the Kramers-Kronig transform of Imλ (ω) . To extract the low-energy renormalization effect, we calculated a simple model for the electron-boson interaction. This model reveals that the contribution of the renormalization at | ω | ≤ 15 meV to the quasiparticle mass is larger than that around 65 meV in underdoped samples.

  15. Role of Ultrasonography of Regional Nodal Basins in Staging Triple-Negative Breast Cancer and Implications For Local-Regional Treatment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shaitelman, Simona F., E-mail: sfshaitelman@mdanderson.org; Tereffe, Welela; Dogan, Basak E.

    2015-09-01

    Purpose: We sought to determine the rate at which regional nodal ultrasonography would increase the nodal disease stage in patients with triple-negative breast cancer (TNBC) beyond the clinical stage determined by physical examination and mammography alone, and significantly affect the treatments delivered to these patients. Methods and Materials: We retrospectively reviewed the charts of women with stages I to III TNBC who underwent physical examination, mammography, breast and regional nodal ultrasonography with needle biopsy of abnormal nodes, and definitive local-regional treatment at our institution between 2004 and 2011. The stages of these patients' disease with and without ultrasonography of the regionalmore » nodal basins were compared using the Pearson χ{sup 2} test. Definitive treatments of patients whose nodal disease was upstaged on the basis of ultrasonographic findings were compared to those of patients whose disease stage remained the same. Results: A total of 572 women met the study requirements. In 111 (19.4%) of these patients, regional nodal ultrasonography with needle biopsy resulted in an increase in disease stage from the original stage by physical examination and mammography alone. Significantly higher percentages of patients whose nodal disease was upstaged by ultrasonographic findings compared to that in patients whose disease was not upstaged underwent neoadjuvant systemic therapy (91.9% and 51.2%, respectively; P<.0001), axillary lymph node dissection (99.1% and 34.5%, respectively; P<.0001), and radiation to the regional nodal basins (88.2% and 29.1%, respectively; P<.0001). Conclusions: Regional nodal ultrasonography in TNBC frequently changes the initial clinical stage and plays an important role in treatment planning.« less

  16. Evaluating Mesorectal Lymph Nodes in Rectal Cancer Before and After Neoadjuvant Chemoradiation Using Thin-Section T2-Weighted Magnetic Resonance Imaging

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Koh, Dow-Mu; Chau, Ian; Tait, Diana

    2008-06-01

    Purpose: To apply thin-section T2-weighted magnetic resoance imaging (MRI) to evaluate the number, size, distribution, and morphology of benign and malignant mesorectal lymph nodes before and after chemoradiation treatment compared with histopathologic findings. Methods and Materials: Twenty-five patients with poor-risk adenocarcinoma of the rectum treated with neoadjuvant chemoradiation were evaluated prospectively. Thin-section T2-weighted MR images obtained before and after chemoradiation treatment were independently reviewed in consensus by 2 expert radiologists to determine the tumor stage, nodal size, nodal distribution, and nodal stage. Total mesorectal excision surgery after chemoradiation allowed MR nodal stage to be compared with histopathology using {kappa} statistics.more » Nodal downstaging was compared using the Chi-square test. Results: Before chemoradiation, 152 mesorectal nodes were visible (mean, 6.2 mm; 100 benign, 52 malignant) and 4 of 52 malignant nodes were in contact with the mesorectal fascia. The nodal staging was 7/25 N0, 10/25 N1, and 7/25 N2. After chemoradiation, only 29 nodes (mean, 4.1 mm; 24 benign, 5 malignant) were visible, and none were in contact with the mesorectal fascia. Nodal downstaging was observed: 20/25 N0 and 5/25 N1 (p < 0.01, Chi-square test). There was good agreement between MRI and pathologic T-staging ({kappa} = 0.64) and N-staging ({kappa} = 0.65) after chemoradiation. Conclusions: Neoadjuvant chemoradiation treatment resulted in a decrease in size and number of malignant- and benign-appearing mesorectal nodes on MRI. Nodal downstaging and nodal regression from the mesorectal fascia were observed after treatment. MRI is a useful tool for assessing nodal response to neoadjuvant treatment.« less

  17. Study of flow over object problems by a nodal discontinuous Galerkin-lattice Boltzmann method

    NASA Astrophysics Data System (ADS)

    Wu, Jie; Shen, Meng; Liu, Chen

    2018-04-01

    The flow over object problems are studied by a nodal discontinuous Galerkin-lattice Boltzmann method (NDG-LBM) in this work. Different from the standard lattice Boltzmann method, the current method applies the nodal discontinuous Galerkin method into the streaming process in LBM to solve the resultant pure convection equation, in which the spatial discretization is completed on unstructured grids and the low-storage explicit Runge-Kutta scheme is used for time marching. The present method then overcomes the disadvantage of standard LBM for depending on the uniform meshes. Moreover, the collision process in the LBM is completed by using the multiple-relaxation-time scheme. After the validation of the NDG-LBM by simulating the lid-driven cavity flow, the simulations of flows over a fixed circular cylinder, a stationary airfoil and rotating-stationary cylinders are performed. Good agreement of present results with previous results is achieved, which indicates that the current NDG-LBM is accurate and effective for flow over object problems.

  18. Combined-modality treatment for advanced oral tongue squamous cell carcinoma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fan, K.-H.; Lin, C.-Y.; Kang, C.-J.

    Purpose: The aim of this study was to investigate prognostic factors in advanced-stage oral tongue cancer treated with postoperative adjuvant therapy and to identify indications for adjuvant concomitant chemoradiotherapy (CCRT). Methods and Materials: We retrospectively reviewed the records of 201 patients with advanced squamous cell carcinoma of the oral tongue managed between January 1995 and November 2002. All had undergone wide excision and neck dissection plus adjuvant radiotherapy or CCRT. Based on postoperative staging, 123 (61.2%) patients had Stage IV and 78 (38.8%) had Stage III disease. All patients were followed for at least 18 months after completion of radiotherapymore » or until death. The median follow-up was 40.4 months for surviving patients. The median dose of radiotherapy was 64.8 Gy (range, 58.8-72.8 Gy). Cisplatin-based regimens were used for chemotherapy. Results: The 3-year overall survival (OS) and recurrence-free survival (RFS) rates were 48% and 50.8%, respectively. Stage, multiple nodal metastases, differentiation, and extracapsular spread (ECS) significantly affected disease-specific survival on univariate analysis. On multivariate analysis, multiple nodal metastases, differentiation, ECS, and CCRT were independent prognostic factors. If ECS was present, only CCRT significantly improved survival (3-year RFS with ECS and with CCRT = 48.2% vs. without CCRT = 15%, p = 0.038). In the presence of other poor prognostic factors, results of the two treatment strategies did not significantly differ. Conclusions: Based on this study, ECS appears to be an absolute indication for adjuvant CCRT. CCRT can not be shown to be statistically better than radiotherapy alone in this retrospective series when ECS is not present.« less

  19. Recovering tubewise power from three-dimensional nodal kinetics calculation during material relocation in an HWR

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kalimullah; Morris, E.E.; Yang, W.S.

    1994-12-31

    To analyze severe accidents in some special-purpose heavy-water reactors made of assemblies consisting of a number of coaxial tubes of aluminum-clad U-Al fuel and aluminum-clad neutron-capturing material, a mechanistic model, MARTINS, for tube beatup, melting, and molten material relocation has been developed and integrated with the DIF3D nodal hexagonal-z reactor kinetics and other phenomenological modules. The DIF3D kinetics homogenizes all materials located and computes the total power produced in an axial segment of a fuel assembly. This paper presents an approximate method, used in MARTINS, to calculate the distribution of this total nodal power into the intact fuel and capturingmore » material tubes and the meat-cladding mixtures relocating during tube disruption. The method accounts for the change in intraassembly radial power profile due to assembly geometry change with the progress of segment-by-segment disruption of different tubes. Earlier methods to recover pinwise power from nodal calculation for liquid-metal-cooled reactors and light water reactors (X-Y and hexagonal unit cells) are not practical for a disrupting assembly having material relocation. Figure 1 shows the assembly`s end view, divided into rings for modeling and analysis. A ring is a coolant subchannel plus the outer surrounding tube. The present method for distributing the nodal power consists of two parts: (a) calculation of the relative values of ring-by-ring power per unit uranium mass and power per unit mass of neutron-capturing material in a given assembly segment, and (b) normalization of these relative values such that the total power of all rings (intact tubes and U-Al-Cp meat-cladding mixtures, where Cp implies the neutron-capturing material) equals the DIF3D-calculated nodal power for the assembly axial segment.« less

  20. Embryonic chirality and the evolution of spiralian left–right asymmetries

    PubMed Central

    2016-01-01

    The group Spiralia includes species with one of the most significant cases of left–right asymmetries in animals: the coiling of the shell of gastropod molluscs (snails). In this animal group, an early event of embryonic chirality controlled by cytoskeleton dynamics and the subsequent differential activation of the genes nodal and Pitx determine the left–right axis of snails, and thus the direction of coiling of the shell. Despite progressive advances in our understanding of left–right axis specification in molluscs, little is known about left–right development in other spiralian taxa. Here, we identify and characterize the expression of nodal and Pitx orthologues in three different spiralian animals—the brachiopod Novocrania anomala, the annelid Owenia fusiformis and the nemertean Lineus ruber—and demonstrate embryonic chirality in the biradial-cleaving spiralian embryo of the bryozoan Membranipora membranacea. We show asymmetric expression of nodal and Pitx in the brachiopod and annelid, respectively, and symmetric expression of Pitx in the nemertean. Our findings indicate that early embryonic chirality is widespread and independent of the cleavage programme in the Spiralia. Additionally, our study illuminates the evolution of nodal and Pitx signalling by demonstrating embryonic asymmetric expression in lineages without obvious adult left–right asymmetries. This article is part of the themed issue ‘Provocative questions in left–right asymmetry’. PMID:27821523

  1. All-to-all sequenced fault detection system

    DOEpatents

    Archer, Charles Jens; Pinnow, Kurt Walter; Ratterman, Joseph D.; Smith, Brian Edward

    2010-11-02

    An apparatus, program product and method enable nodal fault detection by sequencing communications between all system nodes. A master node may coordinate communications between two slave nodes before sequencing to and initiating communications between a new pair of slave nodes. The communications may be analyzed to determine the nodal fault.

  2. Elective Clinical Target Volumes for Conformal Therapy in Anorectal Cancer: A Radiation Therapy Oncology Group Consensus Panel Contouring Atlas

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Myerson, Robert J.; Garofalo, Michael C.; El Naqa, Issam

    2009-07-01

    Purpose: To develop a Radiation Therapy Oncology Group (RTOG) atlas of the elective clinical target volume (CTV) definitions to be used for planning pelvic intensity-modulated radiotherapy (IMRT) for anal and rectal cancers. Methods and Materials: The Gastrointestinal Committee of the RTOG established a task group (the nine physician co-authors) to develop this atlas. They responded to a questionnaire concerning three elective CTVs (CTVA: internal iliac, presacral, and perirectal nodal regions for both anal and rectal case planning; CTVB: external iliac nodal region for anal case planning and for selected rectal cases; CTVC: inguinal nodal region for anal case planning andmore » for select rectal cases), and to outline these areas on individual computed tomographic images. The imaging files were shared via the Advanced Technology Consortium. A program developed by one of the co-authors (I.E.N.) used binomial maximum-likelihood estimates to generate a 95% group consensus contour. The computer-estimated consensus contours were then reviewed by the group and modified to provide a final contouring consensus atlas. Results: The panel achieved consensus CTV definitions to be used as guidelines for the adjuvant therapy of rectal cancer and definitive therapy for anal cancer. The most important difference from similar atlases for gynecologic or genitourinary cancer is mesorectal coverage. Detailed target volume contouring guidelines and images are discussed. Conclusion: This report serves as a template for the definition of the elective CTVs to be used in IMRT planning for anal and rectal cancers, as part of prospective RTOG trials.« less

  3. Encouraging experience in the treatment of nasal type extra-nodal NK/T-cell lymphoma in a non-Asian population.

    PubMed

    Qi, Shunan; Yahalom, Joachim; Hsu, Meier; Chelius, Monica; Lunning, Matthew; Moskowitz, Alison; Horwitz, Steven

    2016-11-01

    Extra-nodal NK/T-cell lymphoma, nasal type (EN-NK/TCL-NT), is rare in the Western world. We launched the current single-institutional retrospective study with Institutional Review Board approval to better understand the disease. 43 EN-NK/TCL-NT patients treated from 1996 to 2014 were analyzed, including 10 (23%) Asians and 33 (76%) non-Asians. 19/26 (73%) early-stage patients received short-course chemotherapy followed by radiotherapy. 14/17 (82%) advanced-stage patients received primary chemotherapy. Complete response rate was significantly higher in the modified-SMILE group than the accelerated-CHOP group (80% vs. 30%, p = 0.015). The 2-year overall survival (OS) and progression-free survival (PFS) were 60% and 40%, respectively. Early-stage disease had significantly higher 2-year OS (87% vs. 21%) and PFS (56% vs.18%) than advanced-stage (p < 0.001). Ethnicity had no prognostic difference. EN-NK/TCL-NT in non-Asians shared similar disease characteristics and treatment outcomes with Asians. Most early-stage patients have achieved durable remissions. Management of advanced-stage disease remains challenging, with frequent progression and high mortality.

  4. Improving the pathologic evaluation of lung cancer resection specimens.

    PubMed

    Osarogiagbon, Raymond U; Hilsenbeck, Holly L; Sales, Elizabeth W; Berry, Allen; Jarrett, Robert W; Giampapa, Christopher S; Finch-Cruz, Clara N; Spencer, David

    2015-08-01

    Accurate post-operative prognostication and management heavily depend on pathologic nodal stage. Patients with nodal metastasis benefit from post-operative adjuvant chemotherapy, those with mediastinal nodal involvement may also benefit from adjuvant radiation therapy. However, the quality of pathologic nodal staging varies significantly, with major survival implications in large populations of patients. We describe the quality gap in pathologic nodal staging, and provide evidence of its potential reversibility by targeted corrective interventions. One intervention, designed to improve the surgical lymphadenectomy, specimen labeling, and secure transfer between the operating theatre and the pathology laboratory, involves use of pre-labeled specimen collection kits. Another intervention involves application of an improved method of gross dissection of lung resection specimens, to reduce the inadvertent loss of intrapulmonary lymph nodes to histologic examination for metastasis. These corrective interventions are the subject of a regional dissemination and implementation project in diverse healthcare systems in a tri-state region of the United States with some of the highest lung cancer incidence and mortality rates. We discuss the potential of these interventions to significantly improve the accuracy of pathologic nodal staging, risk stratification, and the quality of specimens available for development of stage-independent prognostic markers in lung cancer.

  5. Clinical Usefulness of [(18)F]Fluoro-2-Deoxy-D-Glucose Uptake in 178 Head-and-Neck Cancer Patients With Nodal Metastasis Treated With Definitive Chemoradiotherapy: Consideration of Its Prognostic Value and Ability to Provide Guidance for Optimal Selection of Patients for Planned Neck Dissection

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Inokuchi, Haruo, E-mail: h.inokuchi@scchr.j; Kodaira, Takeshi; Tachibana, Hiroyuki

    2011-03-01

    Purpose: To evaluate the clinical effectiveness of pretreatment [(18)F]fluoro-2-deoxy-D-glucose-positron emission tomography for head-and-neck squamous cell carcinoma patients with nodal metastasis treated with chemoradiotherapy. Methods and Materials: Between March 2002 and December 2006, 178 patients with head-and-neck squamous cell carcinoma and nodal metastasis underwent fluoro-2-deoxy-D-glucose positron emission tomography before chemoradiotherapy. Fluoro-2-deoxy-D-glucose uptake by both the primary lesion and the neck node was measured using the standard uptake value (SUV). The overall survival, disease-free survival, local control, nodal progression-free survival, and distant metastasis-free survival rates were calculated, and several prognostic factors were evaluated. Results: The patients with a nodal SUV {>=}6.00 hadmore » a significantly lower 3-year disease-free survival rate than those with a lower SUV (44% vs. 69%, p = .004). On multivariate analysis, a high SUV of nodal disease also proved to be a significantly unfavorable factor for disease-free survival (p = .04, 95% confidence interval [CI], 1.02-3.23), nodal progression-free survival (p = .05; 95% CI, 1.00-4.15), and distant metastasis-free survival (p = .016; 95% CI, 1.25-8.92). Among the patients with a greater nodal SUV ({>=}6.00), those treated with planned neck dissection had better nodal progression-free survival than those in the observation group (p = .04, hazard ratio, 2.36; 95% CI, 1.00-5.85). Conclusion: Among head-and-neck squamous cell carcinoma patients treated with chemoradiotherapy, the pretreatment SUV of nodal disease was one of the strongest prognostic factors and also provided important information for the selection of patients suitable for planned neck dissection.« less

  6. The accuracy of preoperative axillary nodal staging in primary breast cancer by ultrasound is modified by nodal metastatic load and tumor biology

    PubMed Central

    Dihge, Looket; Grabau, Dorthe A.; Rasmussen, Rogvi W.; Bendahl, Pär-Ola; Rydén, Lisa

    2016-01-01

    Abstract Background The outcome of axillary ultrasound (AUS) with fine-needle aspiration biopsy (FNAB) in the diagnostic work-up of primary breast cancer has an impact on therapy decisions. We hypothesize that the accuracy of AUS is modified by nodal metastatic burden and clinico-pathological characteristics. Material and methods The performance of AUS and AUS-guided FNAB for predicting nodal metastases was assessed in a prospective breast cancer cohort subjected for surgery during 2009–2012. Predictors of accuracy were included in multivariate analysis. Results AUS had a sensitivity of 23% and a specificity of 95%, while AUS-guided FNAB obtained 73% and 100%, respectively. AUS-FNAB exclusively detected macro-metastases (median four metastases) and identified patients with more extensive nodal metastatic burden in comparison with sentinel node biopsy. The accuracy of AUS was affected by metastatic size (OR 1.11), obesity (OR 2.46), histological grade (OR 4.43), and HER2-status (OR 3.66); metastatic size and histological grade were significant in the multivariate analysis. Conclusions The clinical utility of AUS in low-risk breast cancer deserves further evaluation as the accuracy decreased with a low nodal metastatic burden. The diagnostic performance is modified by tumor and clinical characteristics. Patients with nodal disease detected by AUS-FNAB represent a group for whom neoadjuvant therapy should be considered. PMID:27050668

  7. Patterns of nodal relapse after surgery and postoperative radiation therapy for carcinomas of the major and minor salivary glands: What is the role of elective neck irradiation?

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chen, Allen M.; Garcia, Joaquin; Lee, Nancy Y.

    2007-03-15

    Purpose: To evaluate the incidence of nodal relapses from carcinomas of the salivary glands among patients with clinically negative necks in an attempt to determine the potential utility of elective neck irradiation (ENI). Methods and Materials: Between 1960 and 2004, 251 patients with clinically N0 carcinomas of the salivary glands were treated with surgery and postoperative radiation therapy. None of the patients had undergone previous neck dissection. Histology was: adenoid cystic (84 patients), mucoepidermoid (60 patients), adenocarcinoma (58 patients), acinic cell (21 patients), undifferentiated (11 patients), carcinoma ex pleomorphic adenoma (7 patients), squamous cell (7 patients), and salivary duct carcinomamore » (3 patients); 131 patients (52%) had ENI. Median follow-up was 62 months (range, 3-267 months). Results: The 5- and 10-year actuarial estimates of nodal relapse were 11% and 13%, respectively. The 10-year actuarial rates of nodal failure were 7%, 5%, 12%, and 16%, for patients with T1, T2, T3, and T4 disease, respectively (p = 0.11). The use of ENI reduced the 10-year nodal failure rate from 26% to 0% (p = 0.0001). The highest crude rates of nodal relapse among those treated without ENI were found in patients with squamous cell carcinoma (67%), undifferentiated carcinoma (50%), adenocarcinoma (34%), and mucoepidermoid carcinoma (29%). There were no nodal failures observed among patients with adenoid cystic or acinic cell histology. Conclusion: ENI effectively prevents nodal relapses and should be used for select patients at high risk for regional failure.« less

  8. Applying Dispersive Changes to Lagrangian Particles in Groundwater Transport Models

    USGS Publications Warehouse

    Konikow, Leonard F.

    2010-01-01

    Method-of-characteristics groundwater transport models require that changes in concentrations computed within an Eulerian framework to account for dispersion be transferred to moving particles used to simulate advective transport. A new algorithm was developed to accomplish this transfer between nodal values and advecting particles more precisely and realistically compared to currently used methods. The new method scales the changes and adjustments of particle concentrations relative to limiting bounds of concentration values determined from the population of adjacent nodal values. The method precludes unrealistic undershoot or overshoot for concentrations of individual particles. In the new method, if dispersion causes cell concentrations to decrease during a time step, those particles in the cell having the highest concentration will decrease the most, and those with the lowest concentration will decrease the least. The converse is true if dispersion is causing concentrations to increase. Furthermore, if the initial concentration on a particle is outside the range of the adjacent nodal values, it will automatically be adjusted in the direction of the acceptable range of values. The new method is inherently mass conservative. ?? US Government 2010.

  9. Applying dispersive changes to Lagrangian particles in groundwater transport models

    USGS Publications Warehouse

    Konikow, Leonard F.

    2010-01-01

    Method-of-characteristics groundwater transport models require that changes in concentrations computed within an Eulerian framework to account for dispersion be transferred to moving particles used to simulate advective transport. A new algorithm was developed to accomplish this transfer between nodal values and advecting particles more precisely and realistically compared to currently used methods. The new method scales the changes and adjustments of particle concentrations relative to limiting bounds of concentration values determined from the population of adjacent nodal values. The method precludes unrealistic undershoot or overshoot for concentrations of individual particles. In the new method, if dispersion causes cell concentrations to decrease during a time step, those particles in the cell having the highest concentration will decrease the most, and those with the lowest concentration will decrease the least. The converse is true if dispersion is causing concentrations to increase. Furthermore, if the initial concentration on a particle is outside the range of the adjacent nodal values, it will automatically be adjusted in the direction of the acceptable range of values. The new method is inherently mass conservative.

  10. Segregated nodal domains of two-dimensional multispecies Bose-Einstein condensates

    NASA Astrophysics Data System (ADS)

    Chang, Shu-Ming; Lin, Chang-Shou; Lin, Tai-Chia; Lin, Wen-Wei

    2004-09-01

    In this paper, we study the distribution of m segregated nodal domains of the m-mixture of Bose-Einstein condensates under positive and large repulsive scattering lengths. It is shown that components of positive bound states may repel each other and form segregated nodal domains as the repulsive scattering lengths go to infinity. Efficient numerical schemes are created to confirm our theoretical results and discover a new phenomenon called verticillate multiplying, i.e., the generation of multiple verticillate structures. In addition, our proposed Gauss-Seidel-type iteration method is very effective in that it converges linearly in 10-20 steps.

  11. Nodal Clearance Rate and Long-Term Efficacy of Individualized Sentinel Node–Based Pelvic Intensity Modulated Radiation Therapy for High-Risk Prostate Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Müller, Arndt-Christian, E-mail: arndt-christian.mueller@med.uni-tuebingen.de; Eckert, Franziska; Paulsen, Frank

    2016-02-01

    Purpose: To assess the efficacy of individual sentinel node (SN)-guided pelvic intensity modulated radiation therapy (IMRT) by determining nodal clearance rate [(n expected nodal involvement − n observed regional recurrences)/n expected nodal involvement] in comparison with surgically staged patients. Methods and Materials: Data on 475 high-risk prostate cancer patients were examined. Sixty-one consecutive patients received pelvic SN-based IMRT (5 × 1.8 Gy/wk to 50.4 Gy [pelvic nodes + individual SN] and an integrated boost with 5 × 2.0 Gy/wk to 70.0 Gy to prostate + [base of] seminal vesicles) and neo-/adjuvant long-term androgen deprivation therapy; 414 patients after SN–pelvic lymph node dissection were used to calculate the expected nodal involvement rate for the radiation therapymore » sample. Biochemical control and overall survival were estimated for the SN-IMRT patients using the Kaplan-Meier method. The expected frequency of nodal involvement in the radiation therapy group was estimated by imputing frequencies of node-positive patients in the surgical sample to the pattern of Gleason, prostate-specific antigen, and T category in the radiation therapy sample. Results: After a median follow-up of 61 months, 5-year OS after SN-guided IMRT reached 84.4%. Biochemical control according to the Phoenix definition was 73.8%. The nodal clearance rate of SN-IMRT reached 94%. Retrospective follow-up evaluation is the main limitation. Conclusions: Radiation treatment of pelvic nodes individualized by inclusion of SNs is an effective regional treatment modality in high-risk prostate cancer patients. The pattern of relapse indicates that the SN-based target volume concept correctly covers individual pelvic nodes. Thus, this SN-based approach justifies further evaluation, including current dose-escalation strategies to the prostate in a larger prospective series.« less

  12. Effect of Resting-State fNIRS Scanning Duration on Functional Brain Connectivity and Graph Theory Metrics of Brain Network.

    PubMed

    Geng, Shujie; Liu, Xiangyu; Biswal, Bharat B; Niu, Haijing

    2017-01-01

    As an emerging brain imaging technique, functional near infrared spectroscopy (fNIRS) has attracted widespread attention for advancing resting-state functional connectivity (FC) and graph theoretical analyses of brain networks. However, it remains largely unknown how the duration of the fNIRS signal scanning is related to stable and reproducible functional brain network features. To answer this question, we collected resting-state fNIRS signals (10-min duration, two runs) from 18 participants and then truncated the hemodynamic time series into 30-s time bins that ranged from 1 to 10 min. Measures of nodal efficiency, nodal betweenness, network local efficiency, global efficiency, and clustering coefficient were computed for each subject at each fNIRS signal acquisition duration. Analyses of the stability and between-run reproducibility were performed to identify optimal time length for each measure. We found that the FC, nodal efficiency and nodal betweenness stabilized and were reproducible after 1 min of fNIRS signal acquisition, whereas network clustering coefficient, local and global efficiencies stabilized after 1 min and were reproducible after 5 min of fNIRS signal acquisition for only local and global efficiencies. These quantitative results provide direct evidence regarding the choice of the resting-state fNIRS scanning duration for functional brain connectivity and topological metric stability of brain network connectivity.

  13. A viscoelastic higher-order beam finite element

    NASA Technical Reports Server (NTRS)

    Johnson, Arthur R.; Tressler, Alexander

    1996-01-01

    A viscoelastic internal variable constitutive theory is applied to a higher-order elastic beam theory and finite element formulation. The behavior of the viscous material in the beam is approximately modeled as a Maxwell solid. The finite element formulation requires additional sets of nodal variables for each relaxation time constant needed by the Maxwell solid. Recent developments in modeling viscoelastic material behavior with strain variables that are conjugate to the elastic strain measures are combined with advances in modeling through-the-thickness stresses and strains in thick beams. The result is a viscous thick-beam finite element that possesses superior characteristics for transient analysis since its nodal viscous forces are not linearly dependent an the nodal velocities, which is the case when damping matrices are used. Instead, the nodal viscous forces are directly dependent on the material's relaxation spectrum and the history of the nodal variables through a differential form of the constitutive law for a Maxwell solid. The thick beam quasistatic analysis is explored herein as a first step towards developing more complex viscoelastic models for thick plates and shells, and for dynamic analyses. The internal variable constitutive theory is derived directly from the Boltzmann superposition theorem. The mechanical strains and the conjugate internal strains are shown to be related through a system of first-order, ordinary differential equations. The total time-dependent stress is the superposition of its elastic and viscous components. Equations of motion for the solid are derived from the virtual work principle using the total time-dependent stress. Numerical examples for the problems of relaxation, creep, and cyclic creep are carried out for a beam made from an orthotropic Maxwell solid.

  14. Age Related Changes in Topological Properties of Brain Functional Network and Structural Connectivity.

    PubMed

    Shah, Chandan; Liu, Jia; Lv, Peilin; Sun, Huaiqiang; Xiao, Yuan; Liu, Jieke; Zhao, Youjin; Zhang, Wenjing; Yao, Li; Gong, Qiyong; Lui, Su

    2018-01-01

    Introduction: There are still uncertainties about the true nature of age related changes in topological properties of the brain functional network and its structural connectivity during various developmental stages. In this cross- sectional study, we investigated the effects of age and its relationship with regional nodal properties of the functional brain network and white matter integrity. Method: DTI and fMRI data were acquired from 458 healthy Chinese participants ranging from age 8 to 81 years. Tractography was conducted on the DTI data using FSL. Graph Theory analyses were conducted on the functional data yielding topological properties of the functional network using SPM and GRETNA toolbox. Two multiple regressions were performed to investigate the effects of age on nodal topological properties of the functional brain network and white matter integrity. Result: For the functional studies, we observed that regional nodal characteristics such as node betweenness were decreased while node degree and node efficiency was increased in relation to increasing age. Perversely, we observed that the relationship between nodal topological properties and fasciculus structures were primarily positive for nodal betweenness but negative for nodal degree and nodal efficiency. Decrease in functional nodal betweenness was primarily located in superior frontal lobe, right occipital lobe and the global hubs. These brain regions also had both direct and indirect anatomical relationships with the 14 fiber bundles. A linear age related decreases in the Fractional anisotropy (FA) value was found in the callosum forceps minor. Conclusion: These results suggests that age related differences were more pronounced in the functional than in structural measure indicating these measures do not have direct one-to-one mapping. Our study also indicates that the fiber bundles with longer fibers exhibited a more pronounced effect on the properties of functional network.

  15. Patterns of failure after the reduced volume approach for elective nodal irradiation in nasopharyngeal carcinoma

    PubMed Central

    Seol, Ki Ho

    2016-01-01

    Purpose To evaluate the patterns of nodal failure after radiotherapy (RT) with the reduced volume approach for elective neck nodal irradiation (ENI) in nasopharyngeal carcinoma (NPC). Materials and Methods Fifty-six NPC patients who underwent definitive chemoradiotherapy with the reduced volume approach for ENI were reviewed. The ENI included retropharyngeal and level II lymph nodes, and only encompassed the echelon inferior to the involved level to eliminate the entire neck irradiation. Patients received either moderate hypofractionated intensity-modulated RT for a total of 72.6 Gy (49.5 Gy to elective nodal areas) or a conventional fractionated three-dimensional conformal RT for a total of 68.4–72 Gy (39.6–45 Gy to elective nodal areas). Patterns of failure, locoregional control, and survival were analyzed. Results The median follow-up was 38 months (range, 3 to 80 months). The out-of-field nodal failure when omitting ENI was none. Three patients developed neck recurrences (one in-field recurrence in the 72.6 Gy irradiated nodal area and two in the elective irradiated region of 39.6 Gy). Overall disease failure at any site developed in 11 patients (19.6%). Among these, there were six local failures (10.7%), three regional failures (5.4%), and five distant metastases (8.9%). The 3-year locoregional control rate was 87.1%, and the distant failure-free rate was 90.4%; disease-free survival and overall survival at 3 years was 80% and 86.8%, respectively. Conclusion No patient developed nodal failure in the omitted ENI site. Our investigation has demonstrated that the reduced volume approach for ENI appears to be a safe treatment approach in NPC. PMID:27104162

  16. SU-E-J-179: Prediction of Pelvic Nodal Coverage Using Mutual Information Between Cone-Beam and Planning CTs

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jani, S; Kishan, A; O'Connell, D

    2014-06-01

    Purpose: To investigate if pelvic nodal coverage for prostate patients undergoing intensity modulated radiotherapy (IMRT) can be predicted using mutual image information computed between planning and cone-beam CTs (CBCTs). Methods: Four patients with high-risk prostate adenocarcinoma were treated with IMRT on a Varian TrueBeam. Plans were designed such that 95% of the nodal planning target volume (PTV) received the prescription dose of 45 Gy (N=1) or 50.4 Gy (N=3). Weekly CBCTs (N=25) were acquired and the nodal clinical target volumes and organs at risk were contoured by a physician. The percent nodal volume receiving prescription dose was recorded as amore » ground truth. Using the recorded shifts performed by the radiation therapists at the time of image acquisition, CBCTs were aligned with the planning kVCT. Mutual image information (MI) was calculated between the CBCT and the aligned planning CT within the contour of the nodal PTV. Due to variable CBCT fields-of-view, CBCT images covering less than 90% of the nodal volume were excluded from the analysis, resulting in the removal of eight CBCTs. Results: A correlation coefficient of 0.40 was observed between the MI metric and the percent of the nodal target volume receiving the prescription dose. One patient's CBCTs had clear outliers from the rest of the patients. Upon further investigation, we discovered image artifacts that were present only in that patient's images. When those four images were excluded, the correlation improved to 0.81. Conclusion: This pilot study shows the potential of predicting pelvic nodal dosimetry by computing the mutual image information between planning CTs and patient setup CBCTs. Importantly, this technique does not involve manual or automatic contouring of the CBCT images. Additional patients and more robust exclusion criteria will help validate our findings.« less

  17. THE PRESENCE OF METASTASES IN REGIONAL LYMPH NODES IS ASSOCIATED WITH TUMOR SIZE AND DEPTH OF INVASION IN SPORADIC GASTRIC ADENOCARCINOMA

    PubMed Central

    CAMBRUZZI, Eduardo; de AZEREDO, Andreza Mariane; KRONHART, Ardala; FOLTZ, Katia Martins; ZETTLER, Cláudio Galeano; PÊGAS, Karla Lais

    2014-01-01

    Background Gastric adenocarcinoma is more often found in men over 50 years in the form of an antral lesion. The tumor has heterogeneous histopathologic features and a poor prognosis (median survival of 15% in five years). Aim To estimate the relationship between the presence of nodal metastasis and other prognostic factors in sporadic gastric adenocarcinoma. Method Were evaluated 164 consecutive cases of gastric adenocarcinoma previously undergone gastrectomy (partial or total), without clinical evidence of distant metastasis, and determined the following variables: topography of the lesion, tumor size, Borrmann macroscopic configuration, histological grade, early or advanced lesions, Lauren histological subtype, presence of signet ring cell, degree of invasion, perigastric lymph node status, angiolymphatic/perineural invasion, and staging. Results Were found 21 early lesions (12.8%) and 143 advanced lesions (87.2%), with a predominance of lesions classified as T3 (n=99/60, 4%) and N1 (n=62/37, 8%). The nodal status was associated with depth of invasion (p<0.001) and tumor size (p<0.001). The staging was related to age (p=0.048), histological grade (p=0.003), and presence of signet ring cells (p = 0.007), angiolymphatic invasion (p = 0.001), and perineural invasion (p=0.003). Conclusion In gastric cancer, lymph node involvement, tumor size and depth of invasion are histopathological data associated with the pattern of growth/tumor spread, suggesting that a wide dissection of perigastric lymph nodes is a fundamental step in the surgical treatment of these patients. PMID:24676292

  18. Total Laryngectomy Versus Larynx Preservation for T4a Larynx Cancer: Patterns of Care and Survival Outcomes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Grover, Surbhi; Swisher-McClure, Samuel; Mitra, Nandita

    2015-07-01

    Purpose: To examine practice patterns and compare survival outcomes between total laryngectomy (TL) and larynx preservation chemoradiation (LP-CRT) in the setting of T4a larynx cancer, using a large national cancer registry. Methods and Materials: Using the National Cancer Database, we identified 969 patients from 2003 to 2006 with T4a squamous cell larynx cancer receiving definitive treatment with either initial TL plus adjuvant therapy or LP-CRT. Univariate and multivariable logistic regression were used to assess predictors of undergoing surgery. Survival outcomes were compared using Kaplan-Meier and propensity score–adjusted and inverse probability of treatment–weighted Cox proportional hazards methods. Sensitivity analyses were performed tomore » account for unmeasured confounders. Results: A total of 616 patients (64%) received LP-CRT, and 353 (36%) received TL. On multivariable logistic regression, patients with advanced nodal disease were less likely to receive TL (N2 vs N0, 26.6% vs 43.4%, odds ratio [OR] 0.52, 95% confidence interval [CI] 0.37-0.73; N3 vs N0, 19.1% vs 43.4%, OR 0.23, 95% CI 0.07-0.77), whereas patients treated in high case-volume facilities were more likely to receive TL (46.1% vs 31.5%, OR 1.78, 95% CI 1.27-2.48). Median survival for TL versus LP was 61 versus 39 months (P<.001). After controlling for potential confounders, LP-CRT had inferior overall survival compared with TL (hazard ratio 1.31, 95% CI 1.10-1.57), and with the inverse probability of treatment–weighted model (hazard ratio 1.25, 95% CI 1.05-1.49). This survival difference was shown to be robust on additional sensitivity analyses. Conclusions: Most patients with T4a larynx cancer receive LP-CRT, despite guidelines suggesting TL as the preferred initial approach. Patients receiving LP-CRT had more advanced nodal disease and worse overall survival. Previous studies of (non-T4a) locally advanced larynx cancer showing no difference in survival between LP-CRT and TL may not apply to T4a disease, and patients should be counseled accordingly.« less

  19. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ng, Sweet Ping, E-mail: sweet.ng@petermac.org; David, Steven; Alamgeer, Muhammad

    Purpose: To assess the diagnostic performance of pretreatment {sup 18}F-fluorodeoxyglucose positron emission tomography/computed tomography ({sup 18}F-FDG PET/CT) and its impact on radiation therapy treatment decisions in patients with locally advanced breast cancer (LABC). Methods and Materials: Patients with LABC with Eastern Cooperative Oncology Group performance status <2 and no contraindication to neoadjuvant chemotherapy, surgery, and adjuvant radiation therapy were enrolled on a prospective trial. All patients had pretreatment conventional imaging (CI) performed, including bilateral breast mammography and ultrasound, bone scan, and CT chest, abdomen, and pelvis scans performed. Informed consent was obtained before enrolment. Pretreatment whole-body {sup 18}F-FDG PET/CT scansmore » were performed on all patients, and results were compared with CI findings. Results: A total of 154 patients with LABC with no clinical or radiologic evidence of distant metastases on CI were enrolled. Median age was 49 years (range, 26-70 years). Imaging with PET/CT detected distant metastatic disease and/or locoregional disease not visualized on CI in 32 patients (20.8%). Distant metastatic disease was detected in 17 patients (11.0%): 6 had bony metastases, 5 had intrathoracic metastases (pulmonary/mediastinal), 2 had distant nodal metastases, 2 had liver metastases, 1 had pulmonary and bony metastases, and 1 had mediastinal and distant nodal metastases. Of the remaining 139 patients, nodal disease outside conventional radiation therapy fields was detected on PET/CT in 15 patients (10.8%), with involvement of ipsilateral internal mammary nodes in 13 and ipsilateral level 5 cervical nodes in 2. Conclusions: Imaging with PET/CT provides superior diagnostic and staging information in patients with LABC compared with CI, which has significant therapeutic implications with respect to radiation therapy management. Imaging with PET/CT should be considered in all patients undergoing primary staging for LABC.« less

  20. Computing an upper bound on contact stress with surrogate duality

    NASA Astrophysics Data System (ADS)

    Xuan, Zhaocheng; Papadopoulos, Panayiotis

    2016-07-01

    We present a method for computing an upper bound on the contact stress of elastic bodies. The continuum model of elastic bodies with contact is first modeled as a constrained optimization problem by using finite elements. An explicit formulation of the total contact force, a fraction function with the numerator as a linear function and the denominator as a quadratic convex function, is derived with only the normalized nodal contact forces as the constrained variables in a standard simplex. Then two bounds are obtained for the sum of the nodal contact forces. The first is an explicit formulation of matrices of the finite element model, derived by maximizing the fraction function under the constraint that the sum of the normalized nodal contact forces is one. The second bound is solved by first maximizing the fraction function subject to the standard simplex and then using Dinkelbach's algorithm for fractional programming to find the maximum—since the fraction function is pseudo concave in a neighborhood of the solution. These two bounds are solved with the problem dimensions being only the number of contact nodes or node pairs, which are much smaller than the dimension for the original problem, namely, the number of degrees of freedom. Next, a scheme for constructing an upper bound on the contact stress is proposed that uses the bounds on the sum of the nodal contact forces obtained on a fine finite element mesh and the nodal contact forces obtained on a coarse finite element mesh, which are problems that can be solved at a lower computational cost. Finally, the proposed method is verified through some examples concerning both frictionless and frictional contact to demonstrate the method's feasibility, efficiency, and robustness.

  1. Nodal gap detection through polar angle-resolved density of states measurements in uniaxial superconductors

    NASA Astrophysics Data System (ADS)

    Tsutsumi, Yasumasa; Nomoto, Takuya; Ikeda, Hiroaki; Machida, Kazushige

    2016-12-01

    We propose a spectroscopic method to identify the nodal gap structure in unconventional superconductors. This method is best suited for locating the horizontal line node and for pinpointing the isolated point nodes by measuring polar angle (θ ) resolved zero-energy density of states N (θ ) . This is measured by specific heat or thermal conductivity at low temperatures under a magnetic field. We examine a variety of uniaxially symmetric nodal structures, including point and/or line nodes with linear and quadratic dispersions, by solving the Eilenberger equation in vortex states. It is found that (a) the maxima of N (θ ) continuously shift from the antinodal to the nodal direction (θn) as a field increases accompanying the oscillation pattern reversal at low and high fields. Furthermore, (b) local minima emerge next to θn on both sides, except for the case of the linear point node. These features are robust and detectable experimentally. Experimental results of N (θ ) performed on several superconductors, UPd2Al3,URu2Si2,CuxBi2Se3 , and UPt3, are examined and commented on in light of the present theory.

  2. A combined dislocation fan-finite element (DF-FE) method for stress field simulation of dislocations emerging at the free surfaces of 3D elastically anisotropic crystals

    NASA Astrophysics Data System (ADS)

    Balusu, K.; Huang, H.

    2017-04-01

    A combined dislocation fan-finite element (DF-FE) method is presented for efficient and accurate simulation of dislocation nodal forces in 3D elastically anisotropic crystals with dislocations intersecting the free surfaces. The finite domain problem is decomposed into half-spaces with singular traction stresses, an infinite domain, and a finite domain with non-singular traction stresses. As such, the singular and non-singular parts of the traction stresses are addressed separately; the dislocation fan (DF) method is introduced to balance the singular traction stresses in the half-spaces while the finite element method (FEM) is employed to enforce the non-singular boundary conditions. The accuracy and efficiency of the DF method is demonstrated using a simple isotropic test case, by comparing it with the analytical solution as well as the FEM solution. The DF-FE method is subsequently used for calculating the dislocation nodal forces in a finite elastically anisotropic crystal, which produces dislocation nodal forces that converge rapidly with increasing mesh resolutions. In comparison, the FEM solution fails to converge, especially for nodes closer to the surfaces.

  3. Assessment of Ultrasound Features Predicting Axillary Nodal Metastasis in Breast Cancer: The Impact of Cortical Thickness

    PubMed Central

    Stachs, A.; Thi, A. Tra-Ha; Dieterich, M.; Stubert, J.; Hartmann, S.; Glass, Ä.; Reimer, T.; Gerber, B.

    2015-01-01

    Purpose: To evaluate the accuracy of axillary ultrasound (AUS) in detecting nodal metastasis in patients with early-stage breast cancer and to identify AUS features with high predictive power. Materials and Methods: Prospective single-center preliminary study in 105 patients with a primary diagnosis of breast cancer and clinically negative axilla. AUS was performed using a 12 MHz linear-array transducer before ultrasound-guided needle biopsy. Nodal characteristics (shape, longitudinal-transverse [LT] axis ratio, margins, cortical thickness, hyperechoic hilum) were correlated with histopathological nodal status after SLNB or axillary lymph node dissection (ALND). Results: Nodal metastases were present in 42/105 patients (40.0%). Univariate analyses showed that absence of hyperechoic hilum, round shape, LT axis ratio<2, sharp margins and cortical thickness>3 mm were associated with lymph node metastasis. Multivariate logistic regression analysis revealed cortical thickness > 3 mm as an independent predictive parameter for nodal involvement. Sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 66.7, 74.6, 63.6, 77.0% and 71.4% respectively when cortical thickness > 3 mm was applied as the criterion for AUS positivity. Axillary tumor volume was low in patients with pT1/2 tumors and negative AUS, since only 3.2% of patients had > 2 metastatic lymph nodes. Conclusion: Cortical thickness>3 mm is a reliable predictor of nodal metastatic involvement. Negative AUS does not exclude lymph node metastases, but extensive axillary tumor volume is rare. PMID:27689144

  4. Developmental changes in electrophysiological characteristics of human induced Pluripotent Stem Cell-derived cardiomyocytes

    PubMed Central

    Ben-Ari, Meital; Naor, Shulamit; Zeevi-Levin, Naama; Schick, Revital; Ben Jehuda, Ronen; Reiter, Irina; Raveh, Amit; Grijnevitch, Inna; Barak, Omri; Rosen, Michael R.; Weissman, Amir; Binah, Ofer

    2016-01-01

    Background Previous studies proposed that throughout differentiation of human induced Pluripotent Stem Cell-derived cardiomyocytes (iPSC-CMs) only 3 types of action potentials (AP) exist: nodal, atrial and ventricular-like. Objective To investigate whether there are precisely 3 phenotypes or a continuum exists among them, we tested 2 hypotheses: (1) during culture development a cardiac precursor cell is present that - depending on age - can evolve into the 3 phenotypes. (2) The predominant pattern is early prevalence of nodal phenotype, transient appearance of atrial phenotype, evolution to ventricular phenotype, and persistence of transitional phenotypes. Methods To test these hypotheses we: (1) performed FACS analysis of nodal, atrial and ventricular markers; (2) recorded AP from 280 7-to-95 day old iPSC-CMs; (3) analyzed AP characteristics. Results The major findings were: (1) FACS analysis of 30 and 60-day old cultures showed that an iPSC-CMs population shifts from nodal into atrial/ventricular phenotype, while including significant transitional populations.(2) The AP population did not consist of 3 distinct phenotypes; (3) Culture aging was associated with a shift from nodal to ventricular dominance, with a transient (57–70 days) appearance of atrial phenotype; (4) Beat Rate Variability was more prominent in nodal than ventricular cardiomyocytes while If density increased in older cultures. Conclusions From the onset of development the iPSC-CMs population includes nodal, atrial and ventricular AP and a broad spectrum of transitional phenotypes. The most readily distinguishable phenotype is atrial which appears only transiently, yet dominates at 57–70 days of evolution. PMID:27639456

  5. A posteriori error estimation for multi-stage Runge–Kutta IMEX schemes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chaudhry, Jehanzeb H.; Collins, J. B.; Shadid, John N.

    Implicit–Explicit (IMEX) schemes are widely used for time integration methods for approximating solutions to a large class of problems. In this work, we develop accurate a posteriori error estimates of a quantity-of-interest for approximations obtained from multi-stage IMEX schemes. This is done by first defining a finite element method that is nodally equivalent to an IMEX scheme, then using typical methods for adjoint-based error estimation. Furthermore, the use of a nodally equivalent finite element method allows a decomposition of the error into multiple components, each describing the effect of a different portion of the method on the total error inmore » a quantity-of-interest.« less

  6. A posteriori error estimation for multi-stage Runge–Kutta IMEX schemes

    DOE PAGES

    Chaudhry, Jehanzeb H.; Collins, J. B.; Shadid, John N.

    2017-02-05

    Implicit–Explicit (IMEX) schemes are widely used for time integration methods for approximating solutions to a large class of problems. In this work, we develop accurate a posteriori error estimates of a quantity-of-interest for approximations obtained from multi-stage IMEX schemes. This is done by first defining a finite element method that is nodally equivalent to an IMEX scheme, then using typical methods for adjoint-based error estimation. Furthermore, the use of a nodally equivalent finite element method allows a decomposition of the error into multiple components, each describing the effect of a different portion of the method on the total error inmore » a quantity-of-interest.« less

  7. Tumor microvessel density–associated mast cells in canine nodal lymphoma

    PubMed Central

    Mann, Elizabeth; Whittington, Lisa

    2014-01-01

    Objective: Mast cells are associated in angiogenesis in various human and animal neoplasms. However, association of mast cells with tumor microvessel density in canine lymphoma was not previously documented. The objective of the study is to determine if mast cells are increased in canine nodal lymphomas and to evaluate their correlation with tumor microvessel density and grading of lymphomas. Methods: Nodal lymphomas from 33 dogs were studied and compared with nonneoplastic lymph nodes from 6 dogs as control. Mast cell count was made on Toluidine blue stained sections. Immunohistochemistry using antibody against Factor VIII was employed to visualize and determine microvessel density. Results: The mast cell count in lymphoma (2.95 ± 2.4) was significantly higher (p < 0.05) than that in the control (0.83 ± 0.3) and was positively correlated with tumor microvessel density (r = 0.44, p = 0.009). Significant difference was not observed in mast cell count and tumor microvessel density among different gradings of lymphomas. Conclusions: Mast cells are associated with tumor microvessel density in canine nodal lymphoma with no significant difference among gradings of lymphomas. Mast cells may play an important role in development of canine nodal lymphomas. Further detailed investigation on the role of mast cells as important part of tumor microenvironment in canine nodal lymphomas is recommended. PMID:26770752

  8. Tumor Volume Is a Prognostic Factor in Non-Small-Cell Lung Cancer Treated With Chemoradiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Alexander, Brian M.; Othus, Megan; Caglar, Hale B.

    2011-04-01

    Purpose: To investigate whether primary tumor and nodal volumes defined on radiotherapy planning scans are correlated with outcome (survival and recurrence) after combined-modality treatment. Methods and Materials: A retrospective review of patients with Stage III non-small-cell lung cancer treated with chemoradiation at Brigham and Women's Hospital/Dana-Farber Cancer Institute from 2000 to 2006 was performed. Tumor and nodal volume measurements, as computed by Eclipse (Varian, Palo Alto, CA), were used as independent variables, along with existing clinical factors, in univariate and multivariate analyses for association with outcomes. Results: For patients treated with definitive chemoradiotherapy, both nodal volume (hazard ratio [HR], 1.09;more » p < 0.01) and tumor volume (HR, 1.03; p < 0.01) were associated with overall survival on multivariate analysis. Both nodal volume (HR, 1.10; p < 0.01) and tumor volume (HR, 1.04; p < 0.01) were also associated with local control but not distant metastases. Conclusions: In addition to traditional surgical staging variables, disease burden, measured by primary tumor and nodal metastases volume, provides information that may be helpful in determining prognosis and identifying groups of patients for which more aggressive local therapy is warranted.« less

  9. Nodal Diffusion Burnable Poison Treatment for Prismatic Reactor Cores

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    A. M. Ougouag; R. M. Ferrer

    2010-10-01

    The prismatic block version of the High Temperature Reactor (HTR) considered as a candidate Very High Temperature Reactor (VHTR)design may use burnable poison pins in locations at some corners of the fuel blocks (i.e., assembly equivalent structures). The presence of any highly absorbing materials, such as these burnable poisons, within fuel blocks for hexagonal geometry, graphite-moderated High Temperature Reactors (HTRs) causes a local inter-block flux depression that most nodal diffusion-based method have failed to properly model or otherwise represent. The location of these burnable poisons near vertices results in an asymmetry in the morphology of the assemblies (or blocks). Hencemore » the resulting inadequacy of traditional homogenization methods, as these “spread” the actually local effect of the burnable poisons throughout the assembly. Furthermore, the actual effect of the burnable poison is primarily local with influence in its immediate vicinity, which happens to include a small region within the same assembly as well as similar regions in the adjacent assemblies. Traditional homogenization methods miss this artifact entirely. This paper presents a novel method for treating the local effect of the burnable poison explicitly in the context of a modern nodal method.« less

  10. Early Chemotherapy Intensification With Escalated BEACOPP in Patients With Advanced-Stage Hodgkin Lymphoma With a Positive Interim Positron Emission Tomography/Computed Tomography Scan After Two ABVD Cycles: Long-Term Results of the GITIL/FIL HD 0607 Trial.

    PubMed

    Gallamini, Andrea; Tarella, Corrado; Viviani, Simonetta; Rossi, Andrea; Patti, Caterina; Mulé, Antonino; Picardi, Marco; Romano, Alessandra; Cantonetti, Maria; La Nasa, Giorgio; Trentin, Livio; Bolis, Silvia; Rapezzi, Davide; Battistini, Roberta; Gottardi, Daniela; Gavarotti, Paolo; Corradini, Paolo; Cimminiello, Michele; Schiavotto, Corrado; Parvis, Guido; Zanotti, Roberta; Gini, Guido; Ferreri, Andrés J M; Viero, Piera; Miglino, Maurizio; Billio, Atto; Avigdor, Abraham; Biggi, Alberto; Fallanca, Federico; Ficola, Umberto; Gregianin, Michele; Chiaravalloti, Agostino; Prosperini, Giuseppe; Bergesio, Fabrizio; Chauvie, Stephane; Pavoni, Chiara; Gianni, Alessandro Massimo; Rambaldi, Alessandro

    2018-02-10

    Purpose To investigate the progression-free survival (PFS) of patients with advanced Hodgkin lymphoma (HL) after a risk-adapted treatment strategy that was based on a positive positron emission tomography scan performed after two doxorubicin, vinblastine, vincristine, and dacarbazine (ABVD) cycles (PET2). Patients and Methods Patients with advanced-stage (IIB to IVB) HL were consecutively enrolled. After two ABVD cycles, PET2 was performed and centrally reviewed according to the Deauville five-point scale. Patients with a positive PET2 were randomly assigned to four cycles of escalated bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, and prednisone (BEACOPP) followed by four cycles of standard BEACOPP with or without rituximab. Patients with a negative PET2 continued ABVD, and those with a large nodal mass at diagnosis (≥ 5 cm) in complete remission with a negative PET at the end of chemotherapy were randomly assigned to radiotherapy or no further treatment. The primary end point was 3-year PFS. Results Of 782 enrolled patients, 150 (19%) had a positive and 630 (81%) a negative PET2. The 3-year PFS of all patients was 82%. The 3-year PFS of those with a positive and negative PET2 was 60% and 87%, respectively ( P < .001). The 3-year PFS of patients with a positive PET2 assigned to BEACOPP with or without rituximab was 63% versus 57% ( P = .53). In 296 patients with both interim and post-ABVD-negative PET who had a large nodal mass at diagnosis, radiotherapy was randomly added after chemotherapy without a significant PFS improvement (97% v 93%, respectively; P = .29). The 3-year overall survival of all 782 patients was 97% (99% and 89% for PET2 negative and positive, respectively). Conclusion The PET-driven switch from ABVD to escalated BEACOPP is feasible and effective in high-risk patients with advanced-stage HL.

  11. How should social mixing be measured: comparing web-based survey and sensor-based methods.

    PubMed

    Smieszek, Timo; Barclay, Victoria C; Seeni, Indulaxmi; Rainey, Jeanette J; Gao, Hongjiang; Uzicanin, Amra; Salathé, Marcel

    2014-03-10

    Contact surveys and diaries have conventionally been used to measure contact networks in different settings for elucidating infectious disease transmission dynamics of respiratory infections. More recently, technological advances have permitted the use of wireless sensor devices, which can be worn by individuals interacting in a particular social context to record high resolution mixing patterns. To date, a direct comparison of these two different methods for collecting contact data has not been performed. We studied the contact network at a United States high school in the spring of 2012. All school members (i.e., students, teachers, and other staff) were invited to wear wireless sensor devices for a single school day, and asked to remember and report the name and duration of all of their close proximity conversational contacts for that day in an online contact survey. We compared the two methods in terms of the resulting network densities, nodal degrees, and degree distributions. We also assessed the correspondence between the methods at the dyadic and individual levels. We found limited congruence in recorded contact data between the online contact survey and wireless sensors. In particular, there was only negligible correlation between the two methods for nodal degree, and the degree distribution differed substantially between both methods. We found that survey underreporting was a significant source of the difference between the two methods, and that this difference could be improved by excluding individuals who reported only a few contact partners. Additionally, survey reporting was more accurate for contacts of longer duration, and very inaccurate for contacts of shorter duration. Finally, female participants tended to report more accurately than male participants. Online contact surveys and wireless sensor devices collected incongruent network data from an identical setting. This finding suggests that these two methods cannot be used interchangeably for informing models of infectious disease dynamics.

  12. Delineation of Supraclavicular Target Volumes in Breast Cancer Radiation Therapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Brown, Lindsay C.; Diehn, Felix E.; Boughey, Judy C.

    Purpose: To map the location of gross supraclavicular metastases in patients with breast cancer, in order to determine areas at highest risk of harboring subclinical disease. Methods and Materials: Patients with axial imaging of gross supraclavicular disease were identified from an institutional breast cancer registry. Locations of the metastatic lymph nodes were transferred onto representative axial computed tomography images of the supraclavicular region and compared with the Radiation Therapy Oncology Group (RTOG) breast cancer atlas for radiation therapy planning. Results: Sixty-two patients with 161 supraclavicular nodal metastases were eligible for study inclusion. At the time of diagnosis, 117 nodal metastasesmore » were present in 44 patients. Forty-four nodal metastases in 18 patients were detected at disease recurrence, 4 of whom had received prior radiation to the supraclavicular fossa. Of the 161 nodal metastases, 95 (59%) were within the RTOG consensus volume, 4 nodal metastases (2%) in 3 patients were marginally within the volume, and 62 nodal metastases (39%) in 30 patients were outside the volume. Supraclavicular disease outside the RTOG consensus volume was located in 3 regions: at the level of the cricoid and thyroid cartilage (superior to the RTOG volume), in the posterolateral supraclavicular fossa (posterolateral to the RTOG volume), and in the lateral low supraclavicular fossa (lateral to the RTOG volume). Only women with multiple supraclavicular metastases had nodal disease that extended superiorly to the level of the thyroid cartilage. Conclusions: For women with risk of harboring subclinical supraclavicular disease warranting the addition of supraclavicular radiation, coverage of the posterior triangle and the lateral low supraclavicular region should be considered. For women with known supraclavicular disease, extension of neck coverage superior to the cricoid cartilage may be warranted.« less

  13. Atlas-Based Segmentation Improves Consistency and Decreases Time Required for Contouring Postoperative Endometrial Cancer Nodal Volumes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Young, Amy V.; Department of Radiation Oncology, St. Luke's-Roosevelt Hospital, New York, NY; Wortham, Angela

    2011-03-01

    Purpose: Accurate target delineation of the nodal volumes is essential for three-dimensional conformal and intensity-modulated radiotherapy planning for endometrial cancer adjuvant therapy. We hypothesized that atlas-based segmentation ('autocontouring') would lead to time savings and more consistent contours among physicians. Methods and Materials: A reference anatomy atlas was constructed using the data from 15 postoperative endometrial cancer patients by contouring the pelvic nodal clinical target volume on the simulation computed tomography scan according to the Radiation Therapy Oncology Group 0418 trial using commercially available software. On the simulation computed tomography scans from 10 additional endometrial cancer patients, the nodal clinical targetmore » volume autocontours were generated. Three radiation oncologists corrected the autocontours and delineated the manual nodal contours under timed conditions while unaware of the other contours. The time difference was determined, and the overlap of the contours was calculated using Dice's coefficient. Results: For all physicians, manual contouring of the pelvic nodal target volumes and editing the autocontours required a mean {+-} standard deviation of 32 {+-} 9 vs. 23 {+-} 7 minutes, respectively (p = .000001), a 26% time savings. For each physician, the time required to delineate the manual contours vs. correcting the autocontours was 30 {+-} 3 vs. 21 {+-} 5 min (p = .003), 39 {+-} 12 vs. 30 {+-} 5 min (p = .055), and 29 {+-} 5 vs. 20 {+-} 5 min (p = .0002). The mean overlap increased from manual contouring (0.77) to correcting the autocontours (0.79; p = .038). Conclusion: The results of our study have shown that autocontouring leads to increased consistency and time savings when contouring the nodal target volumes for adjuvant treatment of endometrial cancer, although the autocontours still required careful editing to ensure that the lymph nodes at risk of recurrence are properly included in the target volume.« less

  14. Prognostic factors and treatment outcomes in 444 patients with mucosal melanoma.

    PubMed

    Heppt, Markus V; Roesch, Alexander; Weide, Benjamin; Gutzmer, Ralf; Meier, Friedegund; Loquai, Carmen; Kähler, Katharina C; Gesierich, Anja; Meissner, Markus; von Bubnoff, Dagmar; Göppner, Daniela; Schlaak, Max; Pföhler, Claudia; Utikal, Jochen; Heinzerling, Lucie; Cosgarea, Ioana; Engel, Jutta; Eckel, Renate; Martens, Alexander; Mirlach, Laura; Satzger, Imke; Schubert-Fritschle, Gabriele; Tietze, Julia K; Berking, Carola

    2017-08-01

    Mucosal melanoma (MM) is a rare but diverse cancer entity. Prognostic factors are not well established for Caucasians with MM. We analysed the disease course of 444 patients from 15 German skin cancer centres. Disease progression was determined with the cumulative incidence function. Survival times were estimated with the Kaplan-Meier method. Prognostic parameters were identified with multivariate Cox regression analysis. Common anatomic sites of primary tumours were head and neck (MMHN, 37.2%), female genital tract (MMFG, 30.4%) and anorectal region (MMAN, 21.8%). MMAN patients showed the highest vertical tumour thickness (p = 0.001), had a more advanced nodal status (p = 0.014) and a higher percentage of metastatic disease (p = 0.001) at diagnosis. Mutations of NRAS (13.8%), KIT (8.6%) and BRAF (6.4%) were evenly distributed across all tumour site groups. Local relapses were observed in 32.4% and most commonly occurred in the MMHN group (p = 0.016). Male gender (p = 0.047), advanced tumour stage (p = 0.001), nodal disease (p = 0.001) and incomplete resection status (p = 0.001) were independent risk factors for disease progression. Overall survival (OS) was highest in the MMFG group (p = 0.030) and in patients without ulceration (p = 0.004). Multivariate risk factors for OS were M stage at diagnosis (p = 0.002) and incomplete resection of the primary tumour (p = 0.001). In this large series of MM patients in a European population, anorectal MM was associated with the poorest prognosis. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. [Clinical application of positron-emission tomography for the identification of cervical nodal metastases of head and neck cancer compared with CT or MRI and clinical palpation].

    PubMed

    Chen, Zhong-Wei; Zhu, Li-Jun; Hou, Qing-Yi; Wang, Qi-Peng; Jiang, Sui; Feng, Hang

    2008-12-01

    To evaluate the value of positron-emission tomography (PET) for the identification of cervical nodal metastases of head and neck cancer compared with CT/MRI and clinical palpation. Forty patients of head and neck cancer underwent PET and CT/MRI examination 2 weeks before surgery. PET, CT/MRI and clinical palpation were interpreted separately to assess regional lymph node status. Histopathologic analysis was used as the gold standard for assessment of the lymph node involvement. Differences in sensitivity, specificity and accuracy among the imaging modalities and clinical palpation were analyzed. The sensitivity of PET for the identification of nodal metastases was 14.3% higher than that of CT/MRI (P = 0.648) and 14.3% higher than that of clinical palpation (P = 0.648), whereas the specificity of PET was 15.4% higher than that of CT/MRI (P = 0.188) and 7.7% higher than that of clinical palpation (P = 0.482). The accuracy of 18F-FDG PET, CT/MRI, and clinical palpation for the identification of cervical nodal metastases was 85.0%, 70.0% and 75.0% respectively. The sensitivity, specificity and accuracy of PET for the detection of cervical nodal metastases was higher than that of CT/MRI and clinical palpation. Although the results did not show a statistically significant difference, PET can still serve as a supplementary method for the identification of nodal metastases of head and neck cancer.

  16. Observation of a nodal chain with Dirac surface states in Ti B2

    NASA Astrophysics Data System (ADS)

    Yi, C.-J.; Lv, B. Q.; Wu, Q. S.; Fu, B.-B.; Gao, X.; Yang, M.; Peng, X.-L.; Li, M.; Huang, Y.-B.; Richard, P.; Shi, M.; Li, G.; Yazyev, Oleg V.; Shi, Y.-G.; Qian, T.; Ding, H.

    2018-05-01

    Topological nodal-line semimetals (TNLSMs) are characterized by symmetry-protected band crossings extending along one-dimensional lines in momentum space. The nodal lines exhibit a variety of possible configurations, such as nodal ring, nodal link, nodal chain, and nodal knot. Here, using angle-resolved photoemission spectroscopy, we observe nodal rings on the orthogonal kz=0 and kx=0 planes of the Brillouin zone in Ti B2 . The nodal rings connect with each other on the intersecting line Γ-K of the orthogonal planes forming a remarkable nodal-chain structure. Furthermore, we observe surface states (SSs) on the (001) cleaved surface, which are consistent with the calculated SSs considering the contribution from both Ti and B terminations. The calculated SSs have novel Dirac-cone-like band structures, which are distinct from the usual drumhead SSs with a single flatband proposed in other TNLSMs.

  17. Is there a benefit to adjuvant radiation in stage III penile cancer after lymph node dissection? Findings from the National Cancer Database.

    PubMed

    Winters, Brian R; Kearns, James T; Holt, Sarah K; Mossanen, Matthew; Lin, Daniel W; Wright, Jonathan L

    2018-03-01

    The role of adjuvant radiation in advanced penile cancer (PC) is unknown. We used the National Cancer Database (NCDB) to determine factors associated with receiving adjuvant radiation (aXRT) and their influence on prognosis in men who underwent inguinal lymph node dissection (ILND) for stage III disease. We queried the NCDB from 1998-2012 for all men with PC who had pathologic nodal status and aXRT data available. Clinical and pathologic variables associated with aXRT were examined using chi-square testing. Logistic regression evaluated the odds of receiving aXRT while multivariate Cox regression analysis evaluated the influence of aXRT on overall survival (OS). A total of 589 patients underwent ILND for stage III PC with 23% (N = 136) receiving aXRT. Mean age was 61.8 ±13.7 years. Factors associated with receiving aXRT included higher pathologic nodal stage (MV OR 1.85, 95% CI: 1.13-3.05), while greater distance of travel (MV OR 0.48, 95% CI: 0.25-0.92), and treatment in an academic setting (MV OR 0.53, 95% CI: 0.35-0.81) were inversely associated with receiving aXRT. On Cox regression analysis, aXRT improved OS (combined HR 0.58, 95% CI: 0.39-0.86), which appeared to have been driven by higher nodal burden (N2: HR 0.53, 95% CI: 0.32-0.88; N1: HR 1.36, 95% CI: 0.60-3.09). Determinants of aXRT delivery in stage III PC appear to be related to the proximity to community cancer centers and greater nodal burden. We find evidence of a survival benefit with the use of aXRT, particularly in those with higher nodal stage. Multi-institutional studies are needed to confirm these findings and improve treatment algorithms for high-stage PC. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. Nodal surface semimetals: Theory and material realization

    NASA Astrophysics Data System (ADS)

    Wu, Weikang; Liu, Ying; Li, Si; Zhong, Chengyong; Yu, Zhi-Ming; Sheng, Xian-Lei; Zhao, Y. X.; Yang, Shengyuan A.

    2018-03-01

    We theoretically study the three-dimensional topological semimetals with nodal surfaces protected by crystalline symmetries. Different from the well-known nodal-point and nodal-line semimetals, in these materials, the conduction and valence bands cross on closed nodal surfaces in the Brillouin zone. We propose different classes of nodal surfaces, both in the absence and in the presence of spin-orbit coupling (SOC). In the absence of SOC, a class of nodal surfaces can be protected by space-time inversion symmetry and sublattice symmetry and characterized by a Z2 index, while another class of nodal surfaces are guaranteed by a combination of nonsymmorphic twofold screw-rotational symmetry and time-reversal symmetry. We show that the inclusion of SOC will destroy the former class of nodal surfaces but may preserve the latter provided that the inversion symmetry is broken. We further generalize the result to magnetically ordered systems and show that protected nodal surfaces can also exist in magnetic materials without and with SOC, given that certain magnetic group symmetry requirements are satisfied. Several concrete nodal-surface material examples are predicted via the first-principles calculations. The possibility of multi-nodal-surface materials is discussed.

  19. Stereotactic Body Radiation Therapy Boost After Concurrent Chemoradiation for Locally Advanced Non-Small Cell Lung Cancer: A Phase 1 Dose Escalation Study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hepel, Jaroslaw T., E-mail: jhepel@lifespan.org; Department of Radiation Oncology, Tufts Medical Center, Tufts University, Boston, Massachusetts; Leonard, Kara Lynne

    Purpose: Stereotactic body radiation therapy (SBRT) boost to primary and nodal disease after chemoradiation has potential to improve outcomes for advanced non-small cell lung cancer (NSCLC). A dose escalation study was initiated to evaluate the maximum tolerated dose (MTD). Methods and Materials: Eligible patients received chemoradiation to a dose of 50.4 Gy in 28 fractions and had primary and nodal volumes appropriate for SBRT boost (<120 cc and <60 cc, respectively). SBRT was delivered in 2 fractions after chemoradiation. Dose was escalated from 16 to 28 Gy in 2 Gy/fraction increments, resulting in 4 dose cohorts. MTD was defined when ≥2 of 6 patients permore » cohort experienced any treatment-related grade 3 to 5 toxicity within 4 weeks of treatment or the maximum dose was reached. Late toxicity, disease control, and survival were also evaluated. Results: Twelve patients (3 per dose level) underwent treatment. All treatment plans met predetermined dose-volume constraints. The mean age was 64 years. Most patients had stage III disease (92%) and were medically inoperable (92%). The maximum dose level was reached with no grade 3 to 5 acute toxicities. At a median follow-up time of 16 months, 1-year local-regional control (LRC) was 78%. LRC was 50% at <24 Gy and 100% at ≥24 Gy (P=.02). Overall survival at 1 year was 67%. Late toxicity (grade 3-5) was seen in only 1 patient who experienced fatal bronchopulmonary hemorrhage (grade 5). There were no predetermined dose constraints for the proximal bronchial-vascular tree (PBV) in this study. This patient's 4-cc PBV dose was substantially higher than that received by other patients in all 4 cohorts and was associated with the toxicity observed: 20.3 Gy (P<.05) and 73.5 Gy (P=.07) for SBRT boost and total treatment, respectively. Conclusions: SBRT boost to both primary and nodal disease after chemoradiation is feasible and well tolerated. Local control rates are encouraging, especially at doses ≥24 Gy in 2 fractions. Toxicity at the PBV is a concern but potentially can be avoided with strict dose-volume constraints.« less

  20. Does chronomodulated radiotherapy improve pathological response in locally advanced rectal cancer?

    PubMed

    Squire, Tim; Buchanan, Grant; Rangiah, David; Davis, Ian; Yip, Desmond; Chua, Yu Jo; Rich, Tyvin; Elsaleh, Hany

    2017-01-01

    The predominant mode of radiation-induced cell death for solid tumours is mitotic catastrophe, which is in part dependent on sublethal damage repair being complete at around 6 h. Circadian variation appears to play a role in normal cellular division, and this could influence tumour response of radiation treatment depending on the time of treatment delivery. We tested the hypothesis that radiation treatment later in the day may improve tumour response and nodal downstaging in rectal cancer patients treated neoadjuvantly with radiation therapy. Recruitment was by retrospective review of 267 rectal cancer patients treated neoadjuvantly in the Department of Radiation Oncology at the Canberra Hospital between January 2010 and November 2015. One hundred and fifty-five patients met the inclusion criteria for which demographic, pathological and imaging data were collected, as well as the time of day patients received treatment with each fraction of radiotherapy. Data analysis was performed using the Statistical Package R with nonparametric methods of significance for all tests set at p < 0.05. Of the 45 female and 110 male patients, the median age was 64. Seventy-three percent had cT3 disease and there was a mean tumour distance from the anal verge of 7 cm. Time to surgical resection following radiotherapy ranged from 4 to 162 days with a median of 50 days, with a complete pathological response seen in 21% of patients. Patients exhibiting a favourable pathological response had smaller median pre- and postradiotherapy tumour size and had a greater change in tumour size following treatment (p < 0.01). Patients who received the majority of their radiotherapy fractions after 12:00 pm were more likely to show a complete or moderate pathological response (p = 0.035) and improved nodal downstaging. There were also more favourable responses amongst patients with longer time to surgical resection postradiotherapy (p < 0.004), although no relationship was seen between response and tumour distance from the anal verge. Females were less likely to exhibit several of the above responses. Neoadjuvant radiotherapy for locally advanced rectal cancer performed later in the day coupled with a longer time period to surgical resection may improve pathological tumour response rates and nodal downstaging. A prospective study in chronomodulated radiotherapy in this disease is warranted.

  1. Development of an efficient multigrid method for the NEM form of the multigroup neutron diffusion equation

    NASA Astrophysics Data System (ADS)

    Al-Chalabi, Rifat M. Khalil

    1997-09-01

    Development of an improvement to the computational efficiency of the existing nested iterative solution strategy of the Nodal Exapansion Method (NEM) nodal based neutron diffusion code NESTLE is presented. The improvement in the solution strategy is the result of developing a multilevel acceleration scheme that does not suffer from the numerical stalling associated with a number of iterative solution methods. The acceleration scheme is based on the multigrid method, which is specifically adapted for incorporation into the NEM nonlinear iterative strategy. This scheme optimizes the computational interplay between the spatial discretization and the NEM nonlinear iterative solution process through the use of the multigrid method. The combination of the NEM nodal method, calculation of the homogenized, neutron nodal balance coefficients (i.e. restriction operator), efficient underlying smoothing algorithm (power method of NESTLE), and the finer mesh reconstruction algorithm (i.e. prolongation operator), all operating on a sequence of coarser spatial nodes, constitutes the multilevel acceleration scheme employed in this research. Two implementations of the multigrid method into the NESTLE code were examined; the Imbedded NEM Strategy and the Imbedded CMFD Strategy. The main difference in implementation between the two methods is that in the Imbedded NEM Strategy, the NEM solution is required at every MG level. Numerical tests have shown that the Imbedded NEM Strategy suffers from divergence at coarse- grid levels, hence all the results for the different benchmarks presented here were obtained using the Imbedded CMFD Strategy. The novelties in the developed MG method are as follows: the formulation of the restriction and prolongation operators, and the selection of the relaxation method. The restriction operator utilizes a variation of the reactor physics, consistent homogenization technique. The prolongation operator is based upon a variant of the pin power reconstruction methodology. The relaxation method, which is the power method, utilizes a constant coefficient matrix within the NEM non-linear iterative strategy. The choice of the MG nesting within the nested iterative strategy enables the incorporation of other non-linear effects with no additional coding effort. In addition, if an eigenvalue problem is being solved, it remains an eigenvalue problem at all grid levels, simplifying coding implementation. The merit of the developed MG method was tested by incorporating it into the NESTLE iterative solver, and employing it to solve four different benchmark problems. In addition to the base cases, three different sensitivity studies are performed, examining the effects of number of MG levels, homogenized coupling coefficients correction (i.e. restriction operator), and fine-mesh reconstruction algorithm (i.e. prolongation operator). The multilevel acceleration scheme developed in this research provides the foundation for developing adaptive multilevel acceleration methods for steady-state and transient NEM nodal neutron diffusion equations. (Abstract shortened by UMI.)

  2. Bcl-2 and BLIMP-1 expression predict worse prognosis in gastric diffuse large B cell lymphoma (DLCBL) while other markers for nodal DLBCL are not useful.

    PubMed

    Martin-Arruti, Maialen; Vaquero, Manuel; Díaz de Otazu, Ramón; Zabalza, Iñaki; Ballesteros, Javier; Roncador, Giovanna; García-Orad, Africa

    2012-04-01

    Previous studies have identified clinicopathological and immunohistochemical differences among diffuse large B cell lymphomas (DLBCL) as a function of disease location. Nevertheless, there is a continuing tendency to generalize the prognostic value of various identified markers without taking into account tumour site. Accordingly, we analysed the prognostic value of several of the immunohistochemical markers that have been proposed for nodal DLBCL in a group of patients with gastric DLBCL. Using histochemical methods, CD10, Bcl-6, Gcet1, MUM-1, Bcl-2 and BLIMP-1 expression was investigated in 43 cases of gastric DBLCL. As in nodal DLBCLs, expression of BLIMP-1, and of Bcl-2 in non-germinal centre B cell-like (non-GCB) patients, was associated with a worse prognosis. However, unlike nodal DBLCL, there was no significant association of prognosis with expression of CD10, Bcl-6, Gcet1 or MUM-1, or with categorization according to Hans or Muris algorithms. Although most markers of prognosis in nodal DLBCL are not useful indicators for gastric DLBCL, Bcl-2 or BLIMP-1 expression does correlate with worse prognosis. These data support the notion that clinicopathological features in DLBCL vary according to the disease location. © 2012 Blackwell Publishing Ltd.

  3. Development and Evaluation of a Hydrostatic Dynamical Core Using the Spectral Element/Discontinuous Galerkin Methods

    DTIC Science & Technology

    2014-04-01

    The CG and DG horizontal discretization employs high-order nodal basis functions associated with Lagrange polynomials based on Gauss-Lobatto- Legendre ...and DG horizontal discretization employs high-order nodal basis functions 29 associated with Lagrange polynomials based on Gauss-Lobatto- Legendre ...Inside 235 each element we build ( 1)N + Gauss-Lobatto- Legendre (GLL) quadrature points, where N 236 indicate the polynomial order of the basis

  4. Long-time stability effects of quadrature and artificial viscosity on nodal discontinuous Galerkin methods for gas dynamics

    NASA Astrophysics Data System (ADS)

    Durant, Bradford; Hackl, Jason; Balachandar, Sivaramakrishnan

    2017-11-01

    Nodal discontinuous Galerkin schemes present an attractive approach to robust high-order solution of the equations of fluid mechanics, but remain accompanied by subtle challenges in their consistent stabilization. The effect of quadrature choices (full mass matrix vs spectral elements), over-integration to manage aliasing errors, and explicit artificial viscosity on the numerical solution of a steady homentropic vortex are assessed over a wide range of resolutions and polynomial orders using quadrilateral elements. In both stagnant and advected vortices in periodic and non-periodic domains the need arises for explicit stabilization beyond the numerical surface fluxes of discontinuous Galerkin spectral elements. Artificial viscosity via the entropy viscosity method is assessed as a stabilizing mechanism. It is shown that the regularity of the artificial viscosity field is essential to its use for long-time stabilization of small-scale features in nodal discontinuous Galerkin solutions of the Euler equations of gas dynamics. Supported by the Department of Energy Predictive Science Academic Alliance Program Contract DE-NA0002378.

  5. An updated Lagrangian discontinuous Galerkin hydrodynamic method for gas dynamics

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wu, Tong; Shashkov, Mikhail Jurievich; Morgan, Nathaniel Ray

    Here, we present a new Lagrangian discontinuous Galerkin (DG) hydrodynamic method for gas dynamics. The new method evolves conserved unknowns in the current configuration, which obviates the Jacobi matrix that maps the element in a reference coordinate system or the initial coordinate system to the current configuration. The density, momentum, and total energy (ρ, ρu, E) are approximated with conservative higher-order Taylor expansions over the element and are limited toward a piecewise constant field near discontinuities using a limiter. Two new limiting methods are presented for enforcing the bounds on the primitive variables of density, velocity, and specific internal energymore » (ρ, u, e). The nodal velocity, and the corresponding forces, are calculated by solving an approximate Riemann problem at the element nodes. An explicit second-order method is used to temporally advance the solution. This new Lagrangian DG hydrodynamic method conserves mass, momentum, and total energy. 1D Cartesian coordinates test problem results are presented to demonstrate the accuracy and convergence order of the new DG method with the new limiters.« less

  6. An updated Lagrangian discontinuous Galerkin hydrodynamic method for gas dynamics

    DOE PAGES

    Wu, Tong; Shashkov, Mikhail Jurievich; Morgan, Nathaniel Ray; ...

    2018-04-09

    Here, we present a new Lagrangian discontinuous Galerkin (DG) hydrodynamic method for gas dynamics. The new method evolves conserved unknowns in the current configuration, which obviates the Jacobi matrix that maps the element in a reference coordinate system or the initial coordinate system to the current configuration. The density, momentum, and total energy (ρ, ρu, E) are approximated with conservative higher-order Taylor expansions over the element and are limited toward a piecewise constant field near discontinuities using a limiter. Two new limiting methods are presented for enforcing the bounds on the primitive variables of density, velocity, and specific internal energymore » (ρ, u, e). The nodal velocity, and the corresponding forces, are calculated by solving an approximate Riemann problem at the element nodes. An explicit second-order method is used to temporally advance the solution. This new Lagrangian DG hydrodynamic method conserves mass, momentum, and total energy. 1D Cartesian coordinates test problem results are presented to demonstrate the accuracy and convergence order of the new DG method with the new limiters.« less

  7. Experimental discovery of nodal chains

    NASA Astrophysics Data System (ADS)

    Yan, Qinghui; Liu, Rongjuan; Yan, Zhongbo; Liu, Boyuan; Chen, Hongsheng; Wang, Zhong; Lu, Ling

    2018-05-01

    Three-dimensional Weyl and Dirac nodal points1 have attracted widespread interest across multiple disciplines and in many platforms but allow for few structural variations. In contrast, nodal lines2-4 can have numerous topological configurations in momentum space, forming nodal rings5-9, nodal chains10-15, nodal links16-20 and nodal knots21,22. However, nodal lines are much less explored because of the lack of an ideal experimental realization23-25. For example, in condensed-matter systems, nodal lines are often fragile to spin-orbit coupling, located away from the Fermi level, coexist with energy-degenerate trivial bands or have a degeneracy line that disperses strongly in energy. Here, overcoming all these difficulties, we theoretically predict and experimentally observe nodal chains in a metallic-mesh photonic crystal having frequency-isolated linear band-touching rings chained across the entire Brillouin zone. These nodal chains are protected by mirror symmetry and have a frequency variation of less than 1%. We use angle-resolved transmission measurements to probe the projected bulk dispersion and perform Fourier-transformed field scans to map out the dispersion of the drumhead surface state. Our results establish an ideal nodal-line material for further study of topological line degeneracies with non-trivial connectivity and consequent wave dynamics that are richer than those in Weyl and Dirac materials.

  8. Worst case estimation of homology design by convex analysis

    NASA Technical Reports Server (NTRS)

    Yoshikawa, N.; Elishakoff, Isaac; Nakagiri, S.

    1998-01-01

    The methodology of homology design is investigated for optimum design of advanced structures. for which the achievement of delicate tasks by the aid of active control system is demanded. The proposed formulation of homology design, based on the finite element sensitivity analysis, necessarily requires the specification of external loadings. The formulation to evaluate the worst case for homology design caused by uncertain fluctuation of loadings is presented by means of the convex model of uncertainty, in which uncertainty variables are assigned to discretized nodal forces and are confined within a conceivable convex hull given as a hyperellipse. The worst case of the distortion from objective homologous deformation is estimated by the Lagrange multiplier method searching the point to maximize the error index on the boundary of the convex hull. The validity of the proposed method is demonstrated in a numerical example using the eleven-bar truss structure.

  9. TGF-β promotes glioma cell growth via activating Nodal expression through Smad and ERK1/2 pathways

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sun, Jing; Liu, Su-zhi; Lin, Yan

    Highlights: •TGF-β promoted Nodal expression in glioma cells. •TGF-β promoted Nodal expression via activating Smad and ERK1/2 pathways. •TGF-β promotes glioma cell growth via activating Nodal expression. -- Abstract: While there were certain studies focusing on the mechanism of TGF-β promoting the growth of glioma cells, the present work revealed another novel mechanism that TGF-β may promote glioma cell growth via enhancing Nodal expression. Our results showed that Nodal expression was significantly upregulated in glioma cells when TGF-β was added, whereas the TGF-β-induced Nodal expression was evidently inhibited by transfection Smad2 or Smad3 siRNAs, and the suppression was especially significantmore » when the Smad3 was downregulated. Another, the attenuation of TGF-β-induced Nodal expression was observed with blockade of the ERK1/2 pathway also. Further detection of the proliferation, apoptosis, and invasion of glioma cells indicated that Nodal overexpression promoted the proliferation and invasion of tumor cells and inhibited their apoptosis, resembling the effect of TGF-β addition. Downregulation of Nodal expression via transfection Nodal-specific siRNA in the presence of TGF-β weakened the promoting effect of the latter on glioma cells growth, and transfecting Nodal siRNA alone in the absence of exogenous TGF-β more profoundly inhibited the growth of glioma cells. These results demonstrated that while both TGF-β and Nodal promoted glioma cells growth, the former might exert such effect by enhancing Nodal expression, which may form a new target for glioma therapy.« less

  10. Nodal domains of a non-separable problem—the right-angled isosceles triangle

    NASA Astrophysics Data System (ADS)

    Aronovitch, Amit; Band, Ram; Fajman, David; Gnutzmann, Sven

    2012-03-01

    We study the nodal set of eigenfunctions of the Laplace operator on the right-angled isosceles triangle. A local analysis of the nodal pattern provides an algorithm for computing the number νn of nodal domains for any eigenfunction. In addition, an exact recursive formula for the number of nodal domains is found to reproduce all existing data. Eventually, we use the recursion formula to analyse a large sequence of nodal counts statistically. Our analysis shows that the distribution of nodal counts for this triangular shape has a much richer structure than the known cases of regular separable shapes or completely irregular shapes. Furthermore, we demonstrate that the nodal count sequence contains information about the periodic orbits of the corresponding classical ray dynamics.

  11. The Impact of the Size of Nodal Metastases on Recurrence Risk in Breast Cancer Patients With 1-3 Positive Axillary Nodes After Mastectomy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Harris, Eleanor E.R., E-mail: Eleanor.harris@moffitt.org; Freilich, Jessica; Lin, Hui-Yi

    Purpose: Use of postmastectomy radiation therapy (PMRT) in breast cancer patients with 1-3 positive nodes is controversial. The objective of this study was to determine whether the size of nodal metastases in this subset could predict who would benefit from PMRT. Methods and Materials: We analyzed 250 breast cancer patients with 1-3 positive nodes after mastectomy treated with contemporary surgery and systemic therapy at our institution. Of these patients, 204 did not receive PMRT and 46 did receive PMRT. Local and regional recurrence risks were stratified by the size of the largest nodal metastasis measured as less than or equalmore » to 5 mm or greater than 5 mm. Results: The median follow-up was 65.6 months. In the whole group, regional recurrences occurred in 2% of patients in whom the largest nodal metastasis measured 5 mm or less vs 6% for those with metastases measuring greater than 5 mm. For non-irradiated patients only, regional recurrence rates were 2% and 9%, respectively. Those with a maximal nodal size greater than 5 mm had a significantly higher cumulative incidence of regional recurrence (P=.013). The 5-year cumulative incidence of a regional recurrence in the non-irradiated group was 2.7% (95% confidence interval [CI], 0.7%-7.2%) for maximal metastasis size of 5 mm or less, 6.9% (95% CI, 1.7%-17.3%) for metastasis size greater than 5 mm, and 16% (95% CI, 3.4%-36.8%) for metastasis size greater than 10 mm. The impact of the maximal nodal size on regional recurrences became insignificant in the multivariable model. Conclusions: In patients with 1-3 positive lymph nodes undergoing mastectomy without radiation, nodal metastasis greater than 5 mm was associated with regional recurrence after mastectomy, but its effect was modified by other factors (such as tumor stage). The size of the largest nodal metastasis may be useful to identify high-risk patients who may benefit from radiation therapy after mastectomy.« less

  12. The orphan receptor ALK7 and the Activin receptor ALK4 mediate signaling by Nodal proteins during vertebrate development.

    PubMed

    Reissmann, E; Jörnvall, H; Blokzijl, A; Andersson, O; Chang, C; Minchiotti, G; Persico, M G; Ibáñez, C F; Brivanlou, A H

    2001-08-01

    Nodal proteins have crucial roles in mesendoderm formation and left-right patterning during vertebrate development. The molecular mechanisms of signal transduction by Nodal and related ligands, however, are not fully understood. In this paper, we present biochemical and functional evidence that the orphan type I serine/threonine kinase receptor ALK7 acts as a receptor for mouse Nodal and Xenopus Nodal-related 1 (Xnr1). Receptor reconstitution experiments indicate that ALK7 collaborates with ActRIIB to confer responsiveness to Xnr1 and Nodal. Both receptors can independently bind Xnr1. In addition, Cripto, an extracellular protein genetically implicated in Nodal signaling, can independently interact with both Xnr1 and ALK7, and its expression greatly enhances the ability of ALK7 and ActRIIB to respond to Nodal ligands. The Activin receptor ALK4 is also able to mediate Nodal signaling but only in the presence of Cripto, with which it can also interact directly. A constitutively activated form of ALK7 mimics the mesendoderm-inducing activity of Xnr1 in Xenopus embryos, whereas a dominant-negative ALK7 specifically blocks the activities of Nodal and Xnr1 but has little effect on other related ligands. In contrast, a dominant-negative ALK4 blocks all mesoderm-inducing ligands tested, including Nodal, Xnr1, Xnr2, Xnr4, and Activin. In agreement with a role in Nodal signaling, ALK7 mRNA is localized to the ectodermal and organizer regions of Xenopus gastrula embryos and is expressed during early stages of mouse embryonic development. Therefore, our results indicate that both ALK4 and ALK7 can mediate signal transduction by Nodal proteins, although ALK7 appears to be a receptor more specifically dedicated to Nodal signaling.

  13. The orphan receptor ALK7 and the Activin receptor ALK4 mediate signaling by Nodal proteins during vertebrate development

    PubMed Central

    Reissmann, Eva; Jörnvall, Henrik; Blokzijl, Andries; Andersson, Olov; Chang, Chenbei; Minchiotti, Gabriella; Persico, M. Graziella; Ibáñez, Carlos F.; Brivanlou, Ali H.

    2001-01-01

    Nodal proteins have crucial roles in mesendoderm formation and left–right patterning during vertebrate development. The molecular mechanisms of signal transduction by Nodal and related ligands, however, are not fully understood. In this paper, we present biochemical and functional evidence that the orphan type I serine/threonine kinase receptor ALK7 acts as a receptor for mouse Nodal and Xenopus Nodal-related 1 (Xnr1). Receptor reconstitution experiments indicate that ALK7 collaborates with ActRIIB to confer responsiveness to Xnr1 and Nodal. Both receptors can independently bind Xnr1. In addition, Cripto, an extracellular protein genetically implicated in Nodal signaling, can independently interact with both Xnr1 and ALK7, and its expression greatly enhances the ability of ALK7 and ActRIIB to respond to Nodal ligands. The Activin receptor ALK4 is also able to mediate Nodal signaling but only in the presence of Cripto, with which it can also interact directly. A constitutively activated form of ALK7 mimics the mesendoderm-inducing activity of Xnr1 in Xenopus embryos, whereas a dominant-negative ALK7 specifically blocks the activities of Nodal and Xnr1 but has little effect on other related ligands. In contrast, a dominant-negative ALK4 blocks all mesoderm-inducing ligands tested, including Nodal, Xnr1, Xnr2, Xnr4, and Activin. In agreement with a role in Nodal signaling, ALK7 mRNA is localized to the ectodermal and organizer regions of Xenopus gastrula embryos and is expressed during early stages of mouse embryonic development. Therefore, our results indicate that both ALK4 and ALK7 can mediate signal transduction by Nodal proteins, although ALK7 appears to be a receptor more specifically dedicated to Nodal signaling. PMID:11485994

  14. Oncological outcomes from trimodality therapy receiving definitive doses of neoadjuvant chemoradiation (≥60 Gy) and factors influencing consideration for surgery in stage III non-small cell lung cancer.

    PubMed

    Vyfhuis, Melissa A L; Bhooshan, Neha; Burrows, Whitney M; Turner, Michelle; Suntharalingam, Mohan; Donahue, James; Nichols, Elizabeth M; Feliciano, Josephine; Bentzen, Søren M; Badiyan, Shahed; Carr, Shamus R; Friedberg, Joseph; Simone, Charles B; Edelman, Martin J; Feigenberg, Steven J; Mohindra, Pranshu

    2017-01-01

    Guidelines for locally advanced non-small cell lung cancer (LA-NSCLC) recommend definitive chemoradiation therapy (CRT) for cN2-N3 disease, reserving surgery for patients with minimal nodal involvement at presentation. The current literature suggests that surgery after CRT for stage III NSCLC can improve freedom-from-recurrence (FFR) but has not consistently demonstrated an improvement in overall survival, perhaps partly due to the low (45-50.4 Gy) preoperative doses delivered that result in low rates of mediastinal nodal clearance. We therefore analyzed factors associated with trimodality therapy receipt and determined outcomes in patients with LA-NSCLC who were treated with definitive doses (≥60 Gy) of neoadjuvant CRT prior to surgery. We retrospectively analyzed 355 consecutive patients with LA-NSCLC who were treated with curative intent between January 2000 and December 2013. The Kaplan-Meier method was used to estimate the overall survival and FFR of patients who were initially planned to receive trimodality treatment but never underwent surgery (unplanned bimodality) compared with those who were never considered to be surgical candidates (planned bimodality) and those who underwent surgical resection after CRT (trimodality). Cox proportional hazards regression with forward selection was used for multivariate analyses, and the Fisher exact test was used to test contingency tables. Patients who received trimodality therapy had a longer median survival than those with unplanned or planned bimodality therapy at 59.9, 20.1, and 17.3 months, respectively ( P < .001). The survival benefit with surgery persisted in patients with stage IIIB ( P < .001) and N3 ( P = .010) nodal disease when mediastinal nodal clearance was achieved. FFR was also improved with surgical resection ( P = .001). Race ( P < .001), stage ( P < .001), performance status ( P < .001), age ( P < .001), and diagnosis of chronic obstructive pulmonary disease ( P = .009) were significant indicators that influenced both the decision to initially choose trimodality therapy at consultation and to actually perform surgical resection. Trimodality treatment significantly improves survival and FFR in patients with LA-NSCLC when definitive doses of radiation with neoadjuvant chemotherapy are employed. We identified important demographic features that predict the use of surgical intervention in patients with stage III NSCLC.

  15. Can involved-field irradiation replace elective nodal irradiation in chemoradiotherapy for esophageal cancer? A systematic review and meta-analysis.

    PubMed

    Wang, Xiaoyue; Miao, Chuanwang; Chen, Zhen; Li, Wanhu; Yuan, Shuanghu; Yu, Jinming; Hu, Xudong

    2017-01-01

    Chemoradiotherapy is the most common treatment for inoperable esophageal cancer. However, there is no consensus on the delineation of the clinical target volume. Elective nodal irradiation (ENI) is recommended for inoperable esophageal cancer. A few studies have reported a decrease in the incidence of radiation-related toxicity of involved-field irradiation (IFI) for esophageal cancer. A systematic review and pooled analysis were performed to determine whether IFI in definitive chemoradiotherapy was more beneficial than ENI for esophageal cancer. The results showed no significant differences in the overall survival and local control rates between the IFI and ENI arms. Meanwhile, the incidences of esophageal and lung toxicities were significantly decreased in the IFI arm. These results suggest that IFI is a feasible treatment option for locally advanced esophageal cancer, especially to minimize irradiation-related toxicity.

  16. Can involved-field irradiation replace elective nodal irradiation in chemoradiotherapy for esophageal cancer? A systematic review and meta-analysis

    PubMed Central

    Wang, Xiaoyue; Miao, Chuanwang; Chen, Zhen; Li, Wanhu; Yuan, Shuanghu; Yu, Jinming; Hu, Xudong

    2017-01-01

    Chemoradiotherapy is the most common treatment for inoperable esophageal cancer. However, there is no consensus on the delineation of the clinical target volume. Elective nodal irradiation (ENI) is recommended for inoperable esophageal cancer. A few studies have reported a decrease in the incidence of radiation-related toxicity of involved-field irradiation (IFI) for esophageal cancer. A systematic review and pooled analysis were performed to determine whether IFI in definitive chemoradiotherapy was more beneficial than ENI for esophageal cancer. The results showed no significant differences in the overall survival and local control rates between the IFI and ENI arms. Meanwhile, the incidences of esophageal and lung toxicities were significantly decreased in the IFI arm. These results suggest that IFI is a feasible treatment option for locally advanced esophageal cancer, especially to minimize irradiation-related toxicity. PMID:28442917

  17. Three-component fermions with surface Fermi arcs in tungsten carbide

    NASA Astrophysics Data System (ADS)

    Ma, J.-Z.; He, J.-B.; Xu, Y.-F.; Lv, B. Q.; Chen, D.; Zhu, W.-L.; Zhang, S.; Kong, L.-Y.; Gao, X.; Rong, L.-Y.; Huang, Y.-B.; Richard, P.; Xi, C.-Y.; Choi, E. S.; Shao, Y.; Wang, Y.-L.; Gao, H.-J.; Dai, X.; Fang, C.; Weng, H.-M.; Chen, G.-F.; Qian, T.; Ding, H.

    2018-04-01

    Topological Dirac and Weyl semimetals not only host quasiparticles analogous to the elementary fermionic particles in high-energy physics, but also have a non-trivial band topology manifested by gapless surface states, which induce exotic surface Fermi arcs1,2. Recent advances suggest new types of topological semimetal, in which spatial symmetries protect gapless electronic excitations without high-energy analogues3-11. Here, using angle-resolved photoemission spectroscopy, we observe triply degenerate nodal points near the Fermi level of tungsten carbide with space group P 6 ¯m 2 (no. 187), in which the low-energy quasiparticles are described as three-component fermions distinct from Dirac and Weyl fermions. We further observe topological surface states, whose constant-energy contours constitute pairs of `Fermi arcs' connecting to the surface projections of the triply degenerate nodal points, proving the non-trivial topology of the newly identified semimetal state.

  18. Coupled field effects in BWR stability simulations using SIMULATE-3K

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Borkowski, J.; Smith, K.; Hagrman, D.

    1996-12-31

    The SIMULATE-3K code is the transient analysis version of the Studsvik advanced nodal reactor analysis code, SIMULATE-3. Recent developments have focused on further broadening the range of transient applications by refinement of core thermal-hydraulic models and on comparison with boiling water reactor (BWR) stability measurements performed at Ringhals unit 1, during the startups of cycles 14 through 17.

  19. ALGORITHM TO REDUCE APPROXIMATION ERROR FROM THE COMPLEX-VARIABLE BOUNDARY-ELEMENT METHOD APPLIED TO SOIL FREEZING.

    USGS Publications Warehouse

    Hromadka, T.V.; Guymon, G.L.

    1985-01-01

    An algorithm is presented for the numerical solution of the Laplace equation boundary-value problem, which is assumed to apply to soil freezing or thawing. The Laplace equation is numerically approximated by the complex-variable boundary-element method. The algorithm aids in reducing integrated relative error by providing a true measure of modeling error along the solution domain boundary. This measure of error can be used to select locations for adding, removing, or relocating nodal points on the boundary or to provide bounds for the integrated relative error of unknown nodal variable values along the boundary.

  20. A Variational Nodal Approach to 2D/1D Pin Resolved Neutron Transport for Pressurized Water Reactors

    DOE PAGES

    Zhang, Tengfei; Lewis, E. E.; Smith, M. A.; ...

    2017-04-18

    A two-dimensional/one-dimensional (2D/1D) variational nodal approach is presented for pressurized water reactor core calculations without fuel-moderator homogenization. A 2D/1D approximation to the within-group neutron transport equation is derived and converted to an even-parity form. The corresponding nodal functional is presented and discretized to obtain response matrix equations. Within the nodes, finite elements in the x-y plane and orthogonal functions in z are used to approximate the spatial flux distribution. On the radial interfaces, orthogonal polynomials are employed; on the axial interfaces, piecewise constants corresponding to the finite elements eliminate the interface homogenization that has been a challenge for method ofmore » characteristics (MOC)-based 2D/1D approximations. The angular discretization utilizes an even-parity integral method within the nodes, and low-order spherical harmonics (P N) on the axial interfaces. The x-y surfaces are treated with high-order P N combined with quasi-reflected interface conditions. Furthermore, the method is applied to the C5G7 benchmark problems and compared to Monte Carlo reference calculations.« less

  1. A Variational Nodal Approach to 2D/1D Pin Resolved Neutron Transport for Pressurized Water Reactors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Zhang, Tengfei; Lewis, E. E.; Smith, M. A.

    A two-dimensional/one-dimensional (2D/1D) variational nodal approach is presented for pressurized water reactor core calculations without fuel-moderator homogenization. A 2D/1D approximation to the within-group neutron transport equation is derived and converted to an even-parity form. The corresponding nodal functional is presented and discretized to obtain response matrix equations. Within the nodes, finite elements in the x-y plane and orthogonal functions in z are used to approximate the spatial flux distribution. On the radial interfaces, orthogonal polynomials are employed; on the axial interfaces, piecewise constants corresponding to the finite elements eliminate the interface homogenization that has been a challenge for method ofmore » characteristics (MOC)-based 2D/1D approximations. The angular discretization utilizes an even-parity integral method within the nodes, and low-order spherical harmonics (P N) on the axial interfaces. The x-y surfaces are treated with high-order P N combined with quasi-reflected interface conditions. Furthermore, the method is applied to the C5G7 benchmark problems and compared to Monte Carlo reference calculations.« less

  2. Effect of Whole Pelvic Radiotherapy for Patients With Locally Advanced Prostate Cancer Treated With Radiotherapy and Long-Term Androgen Deprivation Therapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mantini, Giovanna; Tagliaferri, Luca, E-mail: luca.tagliaferri@rm.unicatt.it; Mattiucci, Gian Carlo

    2011-12-01

    Purpose: To evaluate the effect of whole pelvic radiotherapy (WPRT) in prostate cancer patients treated with RT and long-term (>1 year) androgen deprivation therapy (ADT). Methods and materials: Prostate cancer patients with high-risk features (Stage T3-T4 and/or Gleason score {>=}7 and/or prostate-specific antigen level {>=}20 ng/mL) who had undergone RT and long-term ADT were included in the present analysis. Patients with bowel inflammatory disease, colon diverticula, and colon diverticulitis were excluded from WPRT and treated with prostate-only radiotherapy (PORT). Patients were grouped according to nodal risk involvement as assessed by the Roach formula using different cutoff levels (15%, 20%, 25%,more » and 30%). Biochemical disease-free survival (bDFS) was analyzed in each group according to the RT type (WPRT or PORT). Results: A total of 358 patients treated between 1994 and 2007 were included in the analysis (46.9% with WPRT and 53.1% with PORT). The median duration of ADT was 24 months (range, 12-38). With a median follow-up of 52 months (range, 20-150), the overall 4-year bDFS rate was 90.5%. The 4-year bDFS rate was similar between the patients who had undergone WPRT or PORT (90.4% vs. 90.5%; p = NS). However, in the group of patients with the greatest nodal risk (>30%), a significant bDFS improvement was recorded for the patients who had undergone WPRT (p = .03). No differences were seen in acute toxicity among the patients treated with WPRT or PORT. The late gastrointestinal toxicity was similar in patients treated with PORT or WPRT (p = NS). Conclusions: Our analysis has supported the use of WPRT in association with long-term ADT for patients with high-risk nodal involvement (>30%), although a definitive recommendation should be confirmed by a randomized trial.« less

  3. Accuracy of Computed Tomography for Predicting Pathologic Nodal Extracapsular Extension in Patients With Head-and-Neck Cancer Undergoing Initial Surgical Resection

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Prabhu, Roshan S., E-mail: roshansprabhu@gmail.com; Winship Cancer Institute, Emory University, Atlanta, Georgia; Magliocca, Kelly R.

    2014-01-01

    Purpose: Nodal extracapsular extension (ECE) in patients with head-and-neck cancer increases the loco-regional failure risk and is an indication for adjuvant chemoradiation therapy (CRT). To reduce the risk of requiring trimodality therapy, patients with head-and-neck cancer who are surgical candidates are often treated with definitive CRT when preoperative computed tomographic imaging suggests radiographic ECE. The purpose of this study was to assess the accuracy of preoperative CT imaging for predicting pathologic nodal ECE (pECE). Methods and Materials: The study population consisted of 432 consecutive patients with oral cavity or locally advanced/nonfunctional laryngeal cancer who underwent preoperative CT imaging before initialmore » surgical resection and neck dissection. Specimens with pECE had the extent of ECE graded on a scale from 1 to 4. Results: Radiographic ECE was documented in 46 patients (10.6%), and pECE was observed in 87 (20.1%). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were 43.7%, 97.7%, 82.6%, and 87.3%, respectively. The sensitivity of radiographic ECE increased from 18.8% for grade 1 to 2 ECE, to 52.9% for grade 3, and 72.2% for grade 4. Radiographic ECE criteria of adjacent structure invasion was a better predictor than irregular borders/fat stranding for pECE. Conclusions: Radiographic ECE has poor sensitivity, but excellent specificity for pECE in patients who undergo initial surgical resection. PPV and NPV are reasonable for clinical decision making. The performance of preoperative CT imaging increased as pECE grade increased. Patients with resectable head-and-neck cancer with radiographic ECE based on adjacent structure invasion are at high risk for high-grade pECE requiring adjuvant CRT when treated with initial surgery; definitive CRT as an alternative should be considered where appropriate.« less

  4. ADC Histogram Analysis of Cervical Cancer Aids Detecting Lymphatic Metastases-a Preliminary Study.

    PubMed

    Schob, Stefan; Meyer, Hans Jonas; Pazaitis, Nikolaos; Schramm, Dominik; Bremicker, Kristina; Exner, Marc; Höhn, Anne Kathrin; Garnov, Nikita; Surov, Alexey

    2017-12-01

    Apparent diffusion coefficient (ADC) histogram analysis has been used to some extent in cervical cancer (CC) to distinguish between low-grade and high-grade tumors. Although this differentiation is undoubtedly helpful, it would be even more crucial in the presurgical setting to determine whether a tumor already gained the potential to metastasize via the lymphatic system. So far, no studies investigated the potential of 3T ADC histogram analysis in CC to differentiate between nodal-positive and nodal-negative entities. Therefore, the principal aim of our study was to investigate the potential of 3T ADC histogram analysis to differentiate between CC with and without lymph node metastasis. The second aim was to elucidate possible differences in ADC histogram parameters between CC with limited vs. advanced tumor stages and well-differentiated vs. undifferentiated lesions. Finally, correlations of p53 expression and Ki-67 index with ADC parameters were analyzed. Eighteen female patients (mean age 55.4 years, range 32-79 years) with histopathologically confirmed cervical squamous cell carcinoma of the uterine cervix were prospectively enrolled. Tumor stages, tumor grading, status of metastatic dissemination, Ki67-index, and p53 expression were assessed in these patients. Diffusion weighted imaging (DWI) was obtained in a 3T scanner using the following b values: b0 and b1000 s/mm 2 . Group comparisons using Mann-Whitney U test revealed the following findings: nodal-positive CC had statistically significant lower ADC parameters (ADCmin, ADCmean, median ADC, Mode, p10, p25, p75, and p90) in comparison to nodal-negative CC (all p < 0.05). ADCentropy was significantly elevated (p = 0.046) in tumors with advanced T stages (T3/4) compared to tumors with limited T stage (T2). ADCmin values were different in a statistically significant manner comparing G1/G2 and G3 tumors (40.45 ± 18.63 vs. 65.0 ± 23.63 × 10-5 mm2 s -1 , p = 0.035). Furthermore, Spearman Rho calculation identified an inverse correlation between ADCentropy and p53 expression (r = -0.472, p = 0.048). The main finding of our study is the discriminability of nodal-positive from nodal-negative CC using ADC histogram analysis in 3T DWI. This information is crucial for the gynecological surgeon to identify the optimal treatment strategy for patients suffering from CC. Furthermore, ADCentropy was identified as a potential imaging biomarker for tumor heterogeneity and might be able to indicate further molecular changes like loss of p53 expression, which is associated with EMT and consequentially indicates a poor prognosis in CC. Finally, our study confirmed the findings of previous works, which indicated that histogram analysis of ADC maps can distinguish between low-grade and high-grade CC. In conclusion, it can be stated that ADC histogram analysis provides additional, prognostically important information on tumor biology in CC.

  5. Spinless hourglass nodal-line semimetals

    NASA Astrophysics Data System (ADS)

    Takahashi, Ryo; Hirayama, Motoaki; Murakami, Shuichi

    2017-10-01

    Nodal-line semimetals, one of the topological semimetals, have degeneracy along nodal lines where the band gap is closed. In many cases, the nodal lines appear accidentally, and in such cases it is impossible to determine whether the nodal lines appear or not, only from the crystal symmetry and the electron filling. In this paper, for spinless systems, we show that in specific space groups at 4 N +2 fillings (8 N +4 fillings including the spin degree of freedom), presence of the nodal lines is required regardless of the details of the systems. Here, the spinless systems refer to crystals where the spin-orbit coupling is negligible and the spin degree of freedom can be omitted because of the SU(2) spin degeneracy. In this case the shape of the band structure around these nodal lines is like an hourglass, and we call this a spinless hourglass nodal-line semimetal. We construct a model Hamiltonian as an example and we show that it is always in the spinless hourglass nodal-line semimetal phase even when the model parameters are changed without changing the symmetries of the system. We also establish a list of all the centrosymmetric space groups, under which spinless systems always have hourglass nodal lines, and illustrate where the nodal lines are located. We propose that Al3FeSi2 , whose space-group symmetry is Pbcn (No. 60), is one of the nodal-line semimetals arising from this mechanism.

  6. Response of millet and sorghum to a varying water supply around the primary and nodal roots.

    PubMed

    Rostamza, M; Richards, R A; Watt, M

    2013-07-01

    Cereals have two root systems. The primary system originates from the embryo when the seed germinates and can support the plant until it produces grain. The nodal system can emerge from stem nodes throughout the plant's life; its value for yield is unclear and depends on the environment. The aim of this study was to test the role of nodal roots of sorghum and millet in plant growth in response to variation in soil moisture. Sorghum and millet were chosen as both are adapted to dry conditions. Sorghum and millet were grown in a split-pot system that allowed the primary and nodal roots to be watered separately. When primary and nodal roots were watered (12 % soil water content; SWC), millet nodal roots were seven times longer than those of sorghum and six times longer than millet plants in dry treatments, mainly from an 8-fold increase in branch root length. When soil was allowed to dry in both compartments, millet nodal roots responded and grew 20 % longer branch roots than in the well-watered control. Sorghum nodal roots were unchanged. When only primary roots received water, nodal roots of both species emerged and elongated into extremely dry soil (0.6-1.5 % SWC), possibly with phloem-delivered water from the primary roots in the moist inner pot. Nodal roots were thick, short, branchless and vertical, indicating a tropism that was more pronounced in millet. Total nodal root length increased in both species when the dry soil was covered with plastic, suggesting that stubble retention or leaf mulching could facilitate nodal roots reaching deeper moist layers in dry climates. Greater nodal root length in millet than in sorghum was associated with increased shoot biomass, water uptake and water use efficiency (shoot mass per water). Millet had a more plastic response than sorghum to moisture around the nodal roots due to (1) faster growth and progression through ontogeny for earlier nodal root branch length and (2) partitioning to nodal root length from primary roots, independent of shoot size. Nodal and primary roots have distinct responses to soil moisture that depend on species. They can be selected independently in a breeding programme to shape root architecture. A rapid rate of plant development and enhanced responsiveness to local moisture may be traits that favour nodal roots and water use efficiency at no cost to shoot growth.

  7. Three dimensional flow computations in a turbine scroll

    NASA Technical Reports Server (NTRS)

    Hamed, A.; Ghantous, C. A.

    1982-01-01

    The compressible three dimensional inviscid flow in the scroll and vaneless nozzle of radial inflow turbines is analyzed. A FORTRAN computer program for the numerical solution of this complex flow field using the finite element method is presented. The program input consists of the mass flow rate and stagnation conditions at the scroll inlet and of the finite element discretization parameters and nodal coordinates. The output includes the pressure, Mach number and velocity magnitude and direction at all the nodal points.

  8. Rotating charged black holes accelerated by an electric field

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bicak, Jiri; Kofron, David; Max Planck Institute for Gravitational Physics, Albert Einstein Institute, Am Muehlenberg 1, D-14476 Golm

    The Ernst method of removing nodal singularities from the charged C-metric representing a uniformly accelerated black hole with mass m, charge q and acceleration A by 'adding' an electric field E is generalized. Utilizing the new form of the C-metric found recently, Ernst's simple 'equilibrium condition' mA=qE valid for small accelerations is generalized for arbitrary A. The nodal singularity is removed also in the case of accelerating and rotating charged black holes, and the corresponding equilibrium condition is determined.

  9. Utility of Adjuvant Chemotherapy After Neoadjuvant Chemoradiation and Esophagectomy for Esophageal Cancer.

    PubMed

    Burt, Bryan M; Groth, Shawn S; Sada, Yvonne H; Farjah, Farhood; Cornwell, Lorraine; Sugarbaker, David J; Massarweh, Nader N

    2017-08-01

    To determine whether adjuvant chemotherapy (AC) after neoadjuvant chemoradiation and esophagectomy is associated with improved overall survival for patients with locally advanced esophageal cancer, and to evaluate how pathologic disease response to neoadjuvant treatment impacts this effect. Neoadjuvant chemoradiation is currently the preferred management approach for locoregional esophageal cancer. Although there is interest in the use of AC, the benefit of systemic therapy after neoadjuvant chemoradiation and esophagectomy is unclear. Retrospective cohort study of patients with esophageal cancer treated with neoadjuvant chemoradiation and esophagectomy in the National Cancer Data Base (2006-2012). Among 3592 patients with esophageal cancer (84.7% adenocarcinoma, 15.2% squamous cell carcinoma), 335 (9.3%) were treated with AC. AC was not associated with a significantly lower risk of death among patients with no residual disease (ypT0N0) or residual non-nodal disease (ypT+N0). Among patients with residual nodal disease (ypTanyN+), AC was associated with a 30% lower risk of death in the overall cohort [hazard ratio (HR) 0.70, (0.57-0.85)] and among those with adenocarcinoma [HR 0.69 (0.57-0.85)]. Using a 90-day postoperative landmark, findings were similar. Among patients with postoperative length of stay ≤10 days and no unplanned readmission, AC was associated with approximately 40% lower risk of death among patients with residual nodal disease [overall cohort, HR 0.63 (0.48-0.84); adenocarcinoma, HR 0.66 (0.49-0.88)]. AC after neoadjuvant chemoradiation and esophagectomy is associated with improved survival in patients with residual nodal disease. Our findings suggest AC may provide additional benefit for esophageal cancer patients, and merits further investigation.

  10. Detection of lymph node metastases in pediatric and adolescent/young adult sarcoma: Sentinel lymph node biopsy versus fludeoxyglucose positron emission tomography imaging-A prospective trial.

    PubMed

    Wagner, Lars M; Kremer, Nathalie; Gelfand, Michael J; Sharp, Susan E; Turpin, Brian K; Nagarajan, Rajaram; Tiao, Gregory M; Pressey, Joseph G; Yin, Julie; Dasgupta, Roshni

    2017-01-01

    Lymph node metastases are an important cause of treatment failure for pediatric and adolescent/young adult (AYA) sarcoma patients. Nodal sampling is recommended for certain sarcoma subtypes that have a predilection for lymphatic spread. Sentinel lymph node biopsy (SLNB) may improve the diagnostic yield of nodal sampling, particularly when single-photon emission computed tomography/computed tomography (SPECT-CT) is used to facilitate anatomic localization. Functional imaging with positron emission tomography/computed tomography (PET-CT) is increasingly used for sarcoma staging and is a less invasive alternative to SLNB. To assess the utility of these 2 staging methods, this study prospectively compared SLNB plus SPECT-CT with PET-CT for the identification of nodal metastases in pediatric and AYA patients. Twenty-eight pediatric and AYA sarcoma patients underwent SLNB with SPECT-CT. The histological findings of the excised lymph nodes were then correlated with preoperative PET-CT imaging. A median of 2.4 sentinel nodes were sampled per patient. No wound infections or chronic lymphedema occurred. SLNB identified tumors in 7 of the 28 patients (25%), including 3 patients who had normal PET-CT imaging of the nodal basin. In contrast, PET-CT demonstrated hypermetabolic regional nodes in 14 patients, and this resulted in a positive predictive value of only 29%. The sensitivity and specificity of PET-CT for detecting histologically confirmed nodal metastases were only 57% and 52%, respectively. SLNB can safely guide the rational selection of nodes for biopsy in pediatric and AYA sarcoma patients and can identify therapy-changing nodal disease not appreciated with PET-CT. Cancer 2017;155-160. © 2016 American Cancer Society. © 2016 American Cancer Society.

  11. Comparison of cryoablation with 3D mapping versus conventional mapping for the treatment of atrioventricular re-entrant tachycardia and right-sided paraseptal accessory pathways.

    PubMed

    Russo, Mario S; Drago, Fabrizio; Silvetti, Massimo S; Righi, Daniela; Di Mambro, Corrado; Placidi, Silvia; Prosperi, Monica; Ciani, Michele; Naso Onofrio, Maria T; Cannatà, Vittorio

    2016-06-01

    Aim Transcatheter cryoablation is a well-established technique for the treatment of atrioventricular nodal re-entry tachycardia and atrioventricular re-entry tachycardia in children. Fluoroscopy or three-dimensional mapping systems can be used to perform the ablation procedure. The aim of this study was to compare the success rate of cryoablation procedures for the treatment of right septal accessory pathways and atrioventricular nodal re-entry circuits in children using conventional or three-dimensional mapping and to evaluate whether three-dimensional mapping was associated with reduced patient radiation dose compared with traditional mapping. In 2013, 81 children underwent transcatheter cryoablation at our institution, using conventional mapping in 41 children - 32 atrioventricular nodal re-entry tachycardia and nine atrioventricular re-entry tachycardia - and three-dimensional mapping in 40 children - 24 atrioventricular nodal re-entry tachycardia and 16 atrioventricular re-entry tachycardia. Using conventional mapping, the overall success rate was 78.1 and 66.7% in patients with atrioventricular nodal re-entry tachycardia or atrioventricular re-entry tachycardia, respectively. Using three-dimensional mapping, the overall success rate was 91.6 and 75%, respectively (p=ns). The use of three-dimensional mapping was associated with a reduction in cumulative air kerma and cumulative air kerma-area product of 76.4 and 67.3%, respectively (p<0.05). The use of three-dimensional mapping compared with the conventional fluoroscopy-guided method for cryoablation of right septal accessory pathways and atrioventricular nodal re-entry circuits in children was associated with a significant reduction in patient radiation dose without an increase in success rate.

  12. Incidental Prophylactic Nodal Irradiation and Patterns of Nodal Relapse in Inoperable Early Stage NSCLC Patients Treated With SBRT: A Case-Matched Analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lao, Louis; Department of Radiation Oncology, Auckland City Hospital, Auckland; Hope, Andrew J.

    2014-09-01

    Purpose: Reported rates of non-small cell lung cancer (NSCLC) nodal failure following stereotactic body radiation therapy (SBRT) are lower than those reported in the surgical series when matched for stage. We hypothesized that this effect was due to incidental prophylactic nodal irradiation. Methods and Materials: A prospectively collected group of medically inoperable early stage NSCLC patients from 2004 to 2010 was used to identify cases with nodal relapses. Controls were matched to cases, 2:1, controlling for tumor volume (ie, same or greater) and tumor location (ie, same lobe). Reference (normalized to equivalent dose for 2-Gy fractions [EQD2]) point doses atmore » the ipsilateral hilum and carina, demographic data, and clinical outcomes were extracted from the medical records. Univariate conditional logistical regression analyses were performed with variables of interest. Results: Cases and controls were well matched except for size. The controls, as expected, had larger gross tumor volumes (P=.02). The mean ipsilateral hilar doses were 9.6 Gy and 22.4 Gy for cases and controls, respectively (P=.014). The mean carinal doses were 7.0 Gy and 9.2 Gy, respectively (P=.13). Mediastinal nodal relapses, with and without ipsilateral hilar relapse, were associated with mean ipsilateral hilar doses of 3.6 Gy and 19.8 Gy, respectively (P=.01). The conditional density plot appears to demonstrate an inverse dose-effect relationship between ipsilateral hilar normalized total dose and risk of ipsilateral hilar relapse. Conclusions: Incidental hilar dose greater than 20 Gy is significantly associated with fewer ipsilateral hilar relapses in inoperable early stage NSCLC patients treated with SBRT.« less

  13. On the correct representation of bending and axial deformation in the absolute nodal coordinate formulation with an elastic line approach

    NASA Astrophysics Data System (ADS)

    Gerstmayr, Johannes; Irschik, Hans

    2008-12-01

    In finite element methods that are based on position and slope coordinates, a representation of axial and bending deformation by means of an elastic line approach has become popular. Such beam and plate formulations based on the so-called absolute nodal coordinate formulation have not yet been verified sufficiently enough with respect to analytical results or classical nonlinear rod theories. Examining the existing planar absolute nodal coordinate element, which uses a curvature proportional bending strain expression, it turns out that the deformation does not fully agree with the solution of the geometrically exact theory and, even more serious, the normal force is incorrect. A correction based on the classical ideas of the extensible elastica and geometrically exact theories is applied and a consistent strain energy and bending moment relations are derived. The strain energy of the solid finite element formulation of the absolute nodal coordinate beam is based on the St. Venant-Kirchhoff material: therefore, the strain energy is derived for the latter case and compared to classical nonlinear rod theories. The error in the original absolute nodal coordinate formulation is documented by numerical examples. The numerical example of a large deformation cantilever beam shows that the normal force is incorrect when using the previous approach, while a perfect agreement between the absolute nodal coordinate formulation and the extensible elastica can be gained when applying the proposed modifications. The numerical examples show a very good agreement of reference analytical and numerical solutions with the solutions of the proposed beam formulation for the case of large deformation pre-curved static and dynamic problems, including buckling and eigenvalue analysis. The resulting beam formulation does not employ rotational degrees of freedom and therefore has advantages compared to classical beam elements regarding energy-momentum conservation.

  14. PET-NECK: a multicentre randomised Phase III non-inferiority trial comparing a positron emission tomography-computerised tomography-guided watch-and-wait policy with planned neck dissection in the management of locally advanced (N2/N3) nodal metastases in patients with squamous cell head and neck cancer.

    PubMed

    Mehanna, Hisham; McConkey, Chris C; Rahman, Joy K; Wong, Wai-Lup; Smith, Alison F; Nutting, Chris; Hartley, Andrew Gj; Hall, Peter; Hulme, Claire; Patel, Dharmesh K; Zeidler, Sandra Ventorin von; Robinson, Max; Sanghera, Bal; Fresco, Lydia; Dunn, Janet A

    2017-04-01

    Planned neck dissection (ND) after radical chemoradiotherapy (CRT) for locally advanced nodal metastases in patients with head and neck squamous cell carcinoma (HNSCC) remains controversial. Thirty per cent of ND specimens show histological evidence of tumour. Consequently, a significant proportion of clinicians still practise planned ND. Fludeoxyglucose positron emission tomography (PET)-computerised tomography (CT) scanning demonstrated high negative predictive values for persistent nodal disease, providing a possible alternative paradigm to ND. Evidence is sparse and drawn mainly from retrospective single-institution studies, illustrating the need for a prospective randomised controlled trial. To determine the efficacy and cost-effectiveness of PET-CT-guided surveillance, compared with planned ND, in a multicentre, prospective, randomised setting. A pragmatic randomised non-inferiority trial comparing PET-CT-guided watch-and-wait policy with the current planned ND policy in HNSCC patients with locally advanced nodal metastases and treated with radical CRT. Patients were randomised in a 1 : 1 ratio. Primary outcomes were overall survival (OS) and cost-effectiveness [incremental cost per incremental quality-adjusted life-year (QALY)]. Cost-effectiveness was assessed over the trial period using individual patient data, and over a lifetime horizon using a decision-analytic model. Secondary outcomes were recurrence in the neck, complication rates and quality of life. The recruitment of 560 patients was planned to detect non-inferior OS in the intervention arm with a 90% power and a type I error of 5%, with non-inferiority defined as having a hazard ratio (HR) of no higher than 1.50. An intention-to-treat analysis was performed by Cox's proportional hazards model. Thirty-seven head and neck cancer-treating centres (43 NHS hospitals) throughout the UK. Patients with locally advanced nodal metastases of oropharynx, hypopharynx, larynx, oral or occult HNSCC receiving CRT and fit for ND were recruited. Patients randomised to planned ND before or after CRT (control), or CRT followed by fludeoxyglucose PET-CT 10-12 weeks post CRT with ND only if PET-CT showed incomplete or equivocal response of nodal disease (intervention). Balanced by centre, planned ND timing, CRT schedule, disease site and the tumour, node, metastasis stage. In total, 564 patients were recruited (ND arm, n  = 282; and surveillance arm, n  = 282; 17% N2a, 61% N2b, 18% N2c and 3% N3). Eighty-four per cent had oropharyngeal cancer. Seventy-five per cent of tested cases were p16 positive. The median time to follow-up was 36 months. The HR for OS was 0.92 [95% confidence interval (CI) 0.65 to 1.32], indicating non-inferiority. The upper limit of the non-inferiority HR margin of 1.50, which was informed by patient advisors to the project, lies at the 99.6 percentile of this estimate ( p  = 0.004). There were no differences in this result by p16 status. There were 54 NDs performed in the surveillance arm, with 22 surgical complications, and 221 NDs in the ND arm, with 85 complications. Quality-of-life scores were slightly better in the surveillance arm. Compared with planned ND, PET-CT surveillance produced an incremental net health benefit of 0.16 QALYs (95% CI 0.03 to 0.28 QALYs) over the trial period and 0.21 QALYs (95% CI -0.41 to 0.85 QALYs) over the modelled lifetime horizon. Pragmatic randomised controlled trial with a 36-month median follow-up. PET-CT-guided active surveillance showed similar survival outcomes to ND but resulted in considerably fewer NDs, fewer complications and lower costs, supporting its use in routine practice. PET-CT surveillance is cost-effective in the short term, and long-term cost-effectiveness could be addressed in future work. Current Controlled Trials ISRCTN13735240. This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment ; Vol. 21, No. 17. See the NIHR Journals Library website for further project information.

  15. Amplification and protein overexpression of cyclin D1: Predictor of occult nodal metastasis in early oral cancer.

    PubMed

    Noorlag, Rob; Boeve, Koos; Witjes, Max J H; Koole, Ronald; Peeters, Ton L M; Schuuring, Ed; Willems, Stefan M; van Es, Robert J J

    2017-02-01

    Accurate nodal staging is pivotal for treatment planning in early (stage I-II) oral cancer. Unfortunately, current imaging modalities lack sensitivity to detect occult nodal metastases. Chromosomal region 11q13, including genes CCND1, Fas-associated death domain (FADD), and CTTN, is often amplified in oral cancer with nodal metastases. However, evidence in predicting occult nodal metastases is limited. In 158 patients with early tongue and floor of mouth (FOM) squamous cell carcinomas, both CCND1 amplification and cyclin D1, FADD, and cortactin protein expression were correlated with occult nodal metastases. CCND1 amplification and cyclin D1 expression correlated with occult nodal metastases. Cyclin D1 expression was validated in an independent multicenter cohort, confirming the correlation with occult nodal metastases in early FOM cancers. Cyclin D1 is a predictive biomarker for occult nodal metastases in early FOM cancers. Prospective research on biopsy material should confirm these results before implementing its use in routine clinical practice. © 2016 Wiley Periodicals, Inc. Head Neck 39: 326-333, 2017. © 2016 Wiley Periodicals, Inc.

  16. Patterns of failure after involved field radiotherapy for locally advanced esophageal squamous cell carcinoma.

    PubMed

    Li, Duo-Jie; Li, Hong-Wei; He, Bin; Wang, Geng-Ming; Cai, Han-Fei; Duan, Shi-Miao; Liu, Jing-Jing; Zhang, Ya-Jun; Cui, Zhen; Jiang, Hao

    2016-01-01

    To retrospectively analyze the patterns of failure and the treatment effects of involved-field irradiation (IFI) on patients treated with locally advanced esophageal squamous cell carcinoma (ESCC) and to determine whether IFI is practicable in these patients. A total of 79 patients with locally advanced ESCC underwent three dimensional conformal (3D)CRT) or intensity modulated radiotherapy (IMRT) using IFI or elective nodal irradiation (ENI) according to the target volume. The patterns of failure were defined as local/regional, in-field, out)of)field regional lymph node (LN) and distant failure. With a median follow)up of 32.0 months, failures were observed in 66 (83.6%) patients. The cumulative incidence of local/regional failure (55.8 vs 52.8%) and in)field regional lymph node failure (25.6 vs 19.4%) showed no statistically significant difference between the IFI and the ENI group (p=0.526 and 0.215, respectively). Out)of)field nodal relapse rate of only 7.0% was seen in the IFI group. Three)year survival rates for the ENI and IFI group were 22.2 and 18.6%, respectively (p=0.240), and 3)year distant metastasis rates were 27.8 and 32.6%, respectively (p=0.180). The lung V10, V20, V30 and mean lung dose of the ENI group were greater than those of the IFI group, while the mean lung dose and V10 had statistically significant difference. The patterns of failure and survival rates in the IFI group were similar as in the ENI group; the regional recurrence and distant metastasis are the main cause of treatment failure. IFI is feasible for locally advanced ESCC. Further investigation is needed to increase local control and decrease distant metastasis in these patients.

  17. A global/local analysis method for treating details in structural design

    NASA Technical Reports Server (NTRS)

    Aminpour, Mohammad A.; Mccleary, Susan L.; Ransom, Jonathan B.

    1993-01-01

    A method for analyzing global/local behavior of plate and shell structures is described. In this approach, a detailed finite element model of the local region is incorporated within a coarser global finite element model. The local model need not be nodally compatible (i.e., need not have a one-to-one nodal correspondence) with the global model at their common boundary; therefore, the two models may be constructed independently. The nodal incompatibility of the models is accounted for by introducing appropriate constraint conditions into the potential energy in a hybrid variational formulation. The primary advantage of this method is that the need for transition modeling between global and local models is eliminated. Eliminating transition modeling has two benefits. First, modeling efforts are reduced since tedious and complex transitioning need not be performed. Second, errors due to the mesh distortion, often unavoidable in mesh transitioning, are minimized by avoiding distorted elements beyond what is needed to represent the geometry of the component. The method is applied reduced to a plate loaded in tension and transverse bending. The plate has a central hole, and various hole sixes and shapes are studied. The method is also applied to a composite laminated fuselage panel with a crack emanating from a window in the panel. While this method is applied herein to global/local problems, it is also applicable to the coupled analysis of independently modeled components as well as adaptive refinement.

  18. Involved-field radiotherapy (IFRT) versus elective nodal irradiation (ENI) in combination with concurrent chemotherapy for 239 esophageal cancers: a single institutional retrospective study.

    PubMed

    Yamashita, Hideomi; Takenaka, Ryousuke; Omori, Mami; Imae, Toshikazu; Okuma, Kae; Ohtomo, Kuni; Nakagawa, Keiichi

    2015-08-14

    This retrospective study on early and locally advanced esophageal cancer was conducted to evaluate locoregional failure and its impact on survival by comparing involved field radiotherapy (IFRT) with elective nodal irradiation (ENI) in combination with concurrent chemotherapy. We assessed all patients with esophageal cancer of stages I-IV treated with definitive radiotherapy from June 2000 to March 2014. Between 2000 and 2011, ENI was used for all cases excluding high age cases. After Feb 2011, a prospective study about IFRT was started, and therefore IFRT was used since then for all cases. Concurrent chemotherapy regimen was nedaplatin (80 mg/m(2) at D1 and D29) and 5-fluorouracil (800 mg/m(2) at D1-4 and D29-32). Of the 239 consecutive patients assessed (120 ENI vs. 119 IFRT), 59 patients (24.7%) had stage IV disease and all patients received at least one cycle of chemotherapy. The median follow-up time for survivors was 34.0 months. There were differences in 3-year local control (44.8% vs. 55.5%, p = 0.039), distant control (53.8% vs. 69.9%, p = 0.021) and overall survival (34.8% vs. 51.6%, p = 0.087) rates between ENI vs. IFRT, respectively. Patients treated with IFRT (8 %) demonstrated a significantly lower risk (p = 0.047) of high grade late toxicities than with ENI (16%). IFRT did not increase the risk of initially uninvolved or isolated nodal failures (27.5% in ENI and 13.4% in IFRT). Nodal failure rates in clinically uninvolved nodal stations were not increased with IFRT when compared to ENI. IFRT also resulted in significantly decreased esophageal toxicity, suggesting that IFRT may allow for integration of concurrent systemic chemotherapy in a greater proportion of patients. Both tendencies of improved loco-regional progression-free survival and a significant increased overall survival rate favored the IFRT arm over the ENI arm in this study.

  19. MEG Coherence and DTI Connectivity in mTLE

    PubMed Central

    Nazem-Zadeh, Mohammad-Reza; Bowyer, Susan M.; Moran, John E.; Davoodi-Bojd, Esmaeil; Zillgitt, Andrew; Weiland, Barbara J.; Bagher-Ebadian, Hassan; Mahmoudi, Fariborz; Elisevich, Kost; Soltanian-Zadeh, Hamid

    2017-01-01

    Purpose Magnetoencephalography (MEG) is a noninvasive imaging method for localization of focal epileptiform activity in patients with epilepsy. Diffusion tensor imaging (DTI) is a noninvasive imaging method for measuring the diffusion properties of the underlying white matter tracts through which epileptiform activity is propagated. This study investigates the relationship between the cerebral functional abnormalities quantified by MEG coherence and structural abnormalities quantified by DTI in mesial temporal lobe epilepsy (mTLE). Methods Resting state MEG data was analyzed using MEG coherence source imaging (MEG-CSI) method to determine the coherence in 54 anatomical sites in 17 adult mTLE patients with surgical resection and Engel class I outcome, and 17 age- and gender- matched controls. DTI tractography identified the fiber tracts passing through these same anatomical sites of the same subjects. Then, DTI nodal degree and laterality index were calculated and compared with the corresponding MEG coherence and laterality index. Results MEG coherence laterality, after Bonferroni adjustment, showed significant differences for right versus left mTLE in insular cortex and both lateral orbitofrontal and superior temporal gyri (p<0.017). Likewise, DTI nodal degree laterality, after Bonferroni adjustment, showed significant differences for right versus left mTLE in gyrus rectus, insular cortex, precuneus and superior temporal gyrus (p<0.017). In insular cortex, MEG coherence laterality correlated with DTI nodal degree laterality (R2 = 0.46; p = 0.003) in the cases of mTLE. None of these anatomical sites showed statistically significant differences in coherence laterality between right and left sides of the controls. Coherence laterality was in agreement with the declared side of epileptogenicity in insular cortex (in 82% of patients) and both lateral orbitofrontal (88%) and superior temporal gyri (88%). Nodal degree laterality was also in agreement with the declared side of epileptogenicity in gyrus rectus (in 88% of patients), insular cortex (71%), precuneus (82%) and superior temporal gyrus (94%). Combining all significant laterality indices improved the lateralization accuracy to 94% and 100% for the coherence and nodal degree laterality indices, respectively. Conclusion The associated variations in diffusion properties of fiber tracts quantified by DTI and coherence measures quantified by MEG with respect to epileptogenicity possibly reflect the chronic microstructural cerebral changes associated with functional interictal activity. The proposed methodology for using MEG and DTI to investigate diffusion abnormalities related to focal epileptogenicity and propagation may provide a further means of noninvasive lateralization. PMID:27060092

  20. Chiral topological insulating phases from three-dimensional nodal loop semimetals

    NASA Astrophysics Data System (ADS)

    Li, Linhu; Yin, Chuanhao; Chen, Shu; Araujo, Miguel

    We begin with a minimal model of three-dimensional nodal loop semimetals, and study the effect of anticommuting gap terms. The resulting topological insulating phases are protected by a chiral symmetry, and can be characterized by a winding number defined along the nodal loop. We illustrate the geometric relation between the nodal loop and the gap terms, which has a correspondence to the nodal loop winding number. We further investigate a lattice model and study its edge states under open boundary condition. The edge states hold Dirac cones with the same number as the summation of the winding numbers of each nodal loop in the first Brillouin zone.

  1. Rules for Phase Shifts of Quantum Oscillations in Topological Nodal-Line Semimetals

    NASA Astrophysics Data System (ADS)

    Li, Cequn; Wang, C. M.; Wan, Bo; Wan, Xiangang; Lu, Hai-Zhou; Xie, X. C.

    2018-04-01

    Nodal-line semimetals are topological semimetals in which band touchings form nodal lines or rings. Around a loop that encloses a nodal line, an electron can accumulate a nontrivial π Berry phase, so the phase shift in the Shubnikov-de Haas (SdH) oscillation may give a transport signature for the nodal-line semimetals. However, different experiments have reported contradictory phase shifts, in particular, in the WHM nodal-line semimetals (W =Zr /Hf , H =Si /Ge , M =S /Se /Te ). For a generic model of nodal-line semimetals, we present a systematic calculation for the SdH oscillation of resistivity under a magnetic field normal to the nodal-line plane. From the analytical result of the resistivity, we extract general rules to determine the phase shifts for arbitrary cases and apply them to ZrSiS and Cu3 PdN systems. Depending on the magnetic field directions, carrier types, and cross sections of the Fermi surface, the phase shift shows rich results, quite different from those for normal electrons and Weyl fermions. Our results may help explore transport signatures of topological nodal-line semimetals and can be generalized to other topological phases of matter.

  2. Primary radiotherapy with surgery in reserve for advanced laryngeal carcinoma. Results and complications.

    PubMed

    Croll, G A; Gerritsen, G J; Tiwari, R M; Snow, G B

    1989-08-01

    A retrospective study of a selected group of 58 patients with T3 and T4 squamous cell carcinomas of the larynx presenting between 1974 and 1984 was undertaken. These patients were treated primarily with radical radiotherapy and salvage surgery in reserve. The aim of this study was to examine survival, recurrence rate and the complications after salvage surgery. In 30 patients the tumor was classified as a T3 and in 28 as a T4. In 14 patients (24%) nodal disease in the neck was present prior to the radiotherapy. Follow-up in all patients continued for at least 3 years or until death. Nineteen patients (33%) developed locally recurrent tumor and five (9%) developed nodal metastases to the neck. The recurrence in almost every patient was detected within 2 years after completion of the irradiation. Thirty patients (52%) are alive of whom 29 have no evidence of disease. Of these 30 patients 22 (73%) have their larynx intact and functioning. The 5-year adjusted acturial survival for the whole group of patients is 73%, for the T3N0 group 87% and for the T4N0 group 75%. Patients with nodal disease responded poorly. After salvage surgery severe postoperative complications developed in 37% of the patients. There were no deaths following salvage surgery.

  3. Incidence of cervical lymph node metastasis and its association with outcomes in patients with adenoid cystic carcinoma. An international collaborative study

    PubMed Central

    Amit, Moran; Binenbaum, Yoav; Sharma, Kanika; Ramer, Naomi; Ramer, Ilana; Agbetoba, Abib; Glick, Joelle; Yang, Xinjie; Lei, Delin; Bjørndal, Kristine; Godballe, Christian; Mücke, Thomas; Wolff, Klaus-Dietrich; Fliss, Dan; Eckardt, André M.; Copelli, Chiara; Sesenna, Enrico; Palmer, Frank; Ganly, Ian; Patel, Snehal; Gil, Ziv

    2016-01-01

    Background The patterns of regional metastasis in adenoid cystic carcinoma (ACC) of the head and neck and its association with outcome is not established. Methods We conducted a retrospective multicentered multivariate analysis of 270 patients who underwent neck dissection. Results The incidence rate of neck metastases was 29%. The rate observed in the oral cavity is 37%, and in the major salivary glands is 19% (p = .001). The rate of occult nodal metastases was 17%. Overall 5-year survival rates were 44% in patients undergoing therapeutic neck dissections, and 65% and 73% among those undergoing elective neck dissections, with and without nodal metastases, respectively (p = .017). Multivariate analysis revealed that the primary site, nodal classification, and margin status were independent predictors of survival. Conclusion Our findings support the consideration of elective neck treatment in patients with ACC of the oral cavity. PMID:25060927

  4. Controlling the motion of multiple objects on a Chladni plate

    NASA Astrophysics Data System (ADS)

    Zhou, Quan; Sariola, Veikko; Latifi, Kourosh; Liimatainen, Ville

    2016-09-01

    The origin of the idea of moving objects by acoustic vibration can be traced back to 1787, when Ernst Chladni reported the first detailed studies on the aggregation of sand onto nodal lines of a vibrating plate. Since then and to this date, the prevailing view has been that the particle motion out of nodal lines is random, implying uncontrollability. But how random really is the out-of-nodal-lines motion on a Chladni plate? Here we show that the motion is sufficiently regular to be statistically modelled, predicted and controlled. By playing carefully selected musical notes, we can control the position of multiple objects simultaneously and independently using a single acoustic actuator. Our method allows independent trajectory following, pattern transformation and sorting of multiple miniature objects in a wide range of materials, including electronic components, water droplets loaded on solid carriers, plant seeds, candy balls and metal parts.

  5. Convergence rates for finite element problems with singularities. Part 1: Antiplane shear. [crack

    NASA Technical Reports Server (NTRS)

    Plunkett, R.

    1980-01-01

    The problem of a finite crack in an infinite medium under antiplane shear load is considered. It is shown that the nodal forces at the tip of the crack accurately gives the order of singularity, that n energy release methods can give the strength to better than 1 percent with element size 1/10 the crack length, and that nodal forces give a much better estimate of the stress field than do the elements themselves. The finite element formulation and the factoring of tridiagonal matrices are discussed.

  6. 47 CFR 101.503 - Digital Electronic Message Service Nodal Stations.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 47 Telecommunication 5 2010-10-01 2010-10-01 false Digital Electronic Message Service Nodal... AND SPECIAL RADIO SERVICES FIXED MICROWAVE SERVICES 24 GHz Service and Digital Electronic Message Service § 101.503 Digital Electronic Message Service Nodal Stations. 10.6 GHz DEMS Nodal Stations may be...

  7. Pelvic Nodal Dosing With Registration to the Prostate: Implications for High-Risk Prostate Cancer Patients Receiving Stereotactic Body Radiation Therapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kishan, Amar U., E-mail: aukishan@mednet.ucla.edu; Lamb, James M.; Jani, Shyam S.

    2015-03-15

    Purpose: To determine whether image guidance with rigid registration (RR) to intraprostatic markers (IPMs) yields acceptable coverage of the pelvic lymph nodes in the context of a stereotactic body radiation therapy (SBRT) regimen. Methods and Materials: Four to seven kilovoltage cone-beam CTs (CBCTs) from 12 patients with high-risk prostate cancer were analyzed, allowing approximation of an SBRT regimen. The nodal clinical target volume (CTV{sub N}) and bladder were contoured on all kilovoltage CBCTs. The V{sub 100} CTV{sub N}, expressed as a ratio to the same parameter on the initial plan, and the magnitude of translational shift between RR to themore » IPMs versus RR to the pelvic bones, were computed. The ability of a multimodality bladder filling protocol to minimize bladder height variation was assessed in a separate cohort of 4 patients. Results: Sixty-five CBCTs were assessed. The average V{sub 100} CTV{sub N} was 92.6%, but for a subset of 3 patients the average was 80.0%, compared with 97.8% for the others (P<.0001). The average overall and superior–inferior axis magnitudes of the bony-to-fiducial translations were significantly larger in the subgroup with suboptimal nodal coverage (8.1 vs 3.9 mm and 5.8 vs 2.4 mm, respectively; P<.0001). Relative bladder height changes were also significantly larger in the subgroup with suboptimal nodal coverage (42.9% vs 18.5%; P<.05). Use of a multimodality bladder-filling protocol minimized bladder height variation (P<.001). Conclusion: A majority of patients had acceptable nodal coverage after RR to IPMs, even when approximating SBRT. However, a subset of patients had suboptimal nodal coverage. These patients had large bony-to-fiducial translations and large variations in bladder height. Nodal coverage should be excellent if the superior–inferior axis bony-to-fiducial translation and the relative bladder height change (both easily measured on CBCT) are kept to a minimum. Implementation of a strict bladder filling protocol may achieve this goal.« less

  8. Elsevier Trophoblast Research Award lecture: The multifaceted role of Nodal signaling during mammalian reproduction.

    PubMed

    Park, C B; Dufort, D

    2011-03-01

    Nodal, a secreted signaling protein in the transforming growth factor-beta (TGF-β) superfamily, has established roles in vertebrate development. However, components of the Nodal signaling pathway are also expressed at the maternal-fetal interface and have been implicated in many processes of mammalian reproduction. Emerging evidence indicates that Nodal and its extracellular inhibitor Lefty are expressed in the uterus and complex interactions between the two proteins mediate menstruation, decidualization and embryo implantation. Furthermore, several studies have shown that Nodal from both fetal and maternal sources may regulate trophoblast cell fate and facilitate placentation as both embryonic and uterine-specific Nodal knockout mouse strains exhibit disrupted placenta morphology. Here we review the established and prospective roles of Nodal signaling in facilitating successful pregnancy, including recent evidence supporting a potential link to parturition and preterm birth. Copyright © 2011 Elsevier Ltd. All rights reserved.

  9. A Nodal-independent and tissue-intrinsic mechanism controls heart-looping chirality

    NASA Astrophysics Data System (ADS)

    Noël, Emily S.; Verhoeven, Manon; Lagendijk, Anne Karine; Tessadori, Federico; Smith, Kelly; Choorapoikayil, Suma; den Hertog, Jeroen; Bakkers, Jeroen

    2013-11-01

    Breaking left-right symmetry in bilateria is a major event during embryo development that is required for asymmetric organ position, directional organ looping and lateralized organ function in the adult. Asymmetric expression of Nodal-related genes is hypothesized to be the driving force behind regulation of organ laterality. Here we identify a Nodal-independent mechanism that drives asymmetric heart looping in zebrafish embryos. In a unique mutant defective for the Nodal-related southpaw gene, preferential dextral looping in the heart is maintained, whereas gut and brain asymmetries are randomized. As genetic and pharmacological inhibition of Nodal signalling does not abolish heart asymmetry, a yet undiscovered mechanism controls heart chirality. This mechanism is tissue intrinsic, as explanted hearts maintain ex vivo retain chiral looping behaviour and require actin polymerization and myosin II activity. We find that Nodal signalling regulates actin gene expression, supporting a model in which Nodal signalling amplifies this tissue-intrinsic mechanism of heart looping.

  10. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tinkle, Christopher L.; Weinberg, Vivian; Chen, Lee-May

    Purpose: Evaluate the efficacy and toxicity of image guided brachytherapy using inverse planning simulated annealing (IPSA) high-dose-rate brachytherapy (HDRB) boost for locoregionally advanced cervical cancer. Methods and Materials: From December 2003 through September 2009, 111 patients with primary cervical cancer were treated definitively with IPSA-planned HDRB boost (28 Gy in 4 fractions) after external radiation at our institution. We performed a retrospective review of our experience using image guided brachytherapy. Of the patients, 70% had a tumor size >4 cm, 38% had regional nodal disease, and 15% had clinically evident distant metastasis, including nonregional nodal disease, at the time of diagnosis. Surgicalmore » staging involving pelvic lymph node dissection was performed in 15% of patients, and 93% received concurrent cisplatin-based chemotherapy. Toxicities are reported according to the Common Terminology Criteria for Adverse Events version 4.0 guidelines. Results: With a median follow-up time of 42 months (range, 3-84 months), no acute or late toxicities of grade 4 or higher were observed, and grade 3 toxicities (both acute and late) developed in 8 patients (1 constitutional, 1 hematologic, 2 genitourinary, 4 gastrointestinal). The 4-year Kaplan-Meier estimate of late grade 3 toxicity was 8%. Local recurrence developed in 5 patients (4 to 9 months after HDRB), regional recurrence in 3 (6, 16, and 72 months after HDRB), and locoregional recurrence in 1 (4 months after HDR boost). The 4-year estimates of local, locoregional, and distant control of disease were 94.0%, 91.9%, and 69.1%, respectively. The overall and disease-free survival rates at 4 years were 64.3% (95% confidence interval [CI] of 54%-73%) and 61.0% (95% CI, 51%-70%), respectively. Conclusions: Definitive radiation by use of inverse planned HDRB boost for locoregionally advanced cervical cancer is well tolerated and achieves excellent local control of disease. However, overall survival continues to be limited by the high rates of distant metastasis.« less

  11. F-18-FDG-PET Confined Radiotherapy of Locally Advanced NSCLC With Concomitant Chemotherapy: Results of the PET-PLAN Pilot Trial

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fleckenstein, Jochen; Hellwig, Dirk; Kremp, Stephanie

    2011-11-15

    Purpose: The integration of fluoro-deoxy-D-glucose positron emission tomography (FDG-PET) in the process of radiotherapy (RT) planning of locally advanced non-small-cell lung cancer (NSCLC) may improve diagnostic accuracy and minimize interobserver variability compared with target volume definition solely based on computed tomography. Furthermore, irradiating only FDG-PET-positive findings and omitting elective nodal regions may allow dose escalation by treating smaller volumes. The aim of this prospective pilot trial was to evaluate the therapeutic safety of FDG-PET-based RT treatment planning with an autocontour-derived delineation of the primary tumor. Methods and Materials: Eligible patients had Stages II-III inoperable NSCLC, and simultaneous, platinum-based radiochemotherapy wasmore » indicated. FDG-PET and computed tomography acquisitions in RT treatment planning position were coregistered. The clinical target volume (CTV) included the FDG-PET-defined primary tumor, which was autodelineated with a source-to-background algorithm, plus FDG-PET-positive lymph node stations. Limited by dose restrictions for normal tissues, prescribed total doses were in the range of 66.6 to 73.8 Gy. The primary endpoint was the rate of out-of-field isolated nodal recurrences (INR). Results: As per intent to treat, 32 patients received radiochemotherapy. In 15 of these patients, dose escalation above 66.6 Gy was achieved. No Grade 4 toxicities occurred. After a median follow-up time of 27.2 months, the estimated median survival time was 19.3 months. During the observation period, one INR was observed in 23 evaluable patients. Conclusions: FDG-PET-confined target volume definition in radiochemotherapy of NSCLC, based on a contrast-oriented source-to-background algorithm, was associated with a low risk of INR. It might provide improved tumor control because of dose escalation.« less

  12. Development of a Quantitative Decision Metric for Selecting the Most Suitable Discretization Method for SN Transport Problems

    NASA Astrophysics Data System (ADS)

    Schunert, Sebastian

    In this work we develop a quantitative decision metric for spatial discretization methods of the SN equations. The quantitative decision metric utilizes performance data from selected test problems for computing a fitness score that is used for the selection of the most suitable discretization method for a particular SN transport application. The fitness score is aggregated as a weighted geometric mean of single performance indicators representing various performance aspects relevant to the user. Thus, the fitness function can be adjusted to the particular needs of the code practitioner by adding/removing single performance indicators or changing their importance via the supplied weights. Within this work a special, broad class of methods is considered, referred to as nodal methods. This class is naturally comprised of the DGFEM methods of all function space families. Within this work it is also shown that the Higher Order Diamond Difference (HODD) method is a nodal method. Building on earlier findings that the Arbitrarily High Order Method of the Nodal type (AHOTN) is also a nodal method, a generalized finite-element framework is created to yield as special cases various methods that were developed independently using profoundly different formalisms. A selection of test problems related to a certain performance aspect are considered: an Method of Manufactured Solutions (MMS) test suite for assessing accuracy and execution time, Lathrop's test problem for assessing resilience against occurrence of negative fluxes, and a simple, homogeneous cube test problem to verify if a method possesses the thick diffusive limit. The contending methods are implemented as efficiently as possible under a common SN transport code framework to level the playing field for a fair comparison of their computational load. Numerical results are presented for all three test problems and a qualitative rating of each method's performance is provided for each aspect: accuracy/efficiency, resilience against negative fluxes, and possession of the thick diffusion limit, separately. The choice of the most efficient method depends on the utilized error norm: in Lp error norms higher order methods such as the AHOTN method of order three perform best, while for computing integral quantities the linear nodal (LN) method is most efficient. The most resilient method against occurrence of negative fluxes is the simple corner balance (SCB) method. A validation of the quantitative decision metric is performed based on the NEA box-inbox suite of test problems. The validation exercise comprises two stages: first prediction of the contending methods' performance via the decision metric and second computing the actual scores based on data obtained from the NEA benchmark problem. The comparison of predicted and actual scores via a penalty function (ratio of predicted best performer's score to actual best score) completes the validation exercise. It is found that the decision metric is capable of very accurate predictions (penalty < 10%) in more than 83% of the considered cases and features penalties up to 20% for the remaining cases. An exception to this rule is the third test case NEA-III intentionally set up to incorporate a poor match of the benchmark with the "data" problems. However, even under these worst case conditions the decision metric's suggestions are never detrimental. Suggestions for improving the decision metric's accuracy are to increase the pool of employed data, to refine the mapping of a given configuration to a case in the database, and to better characterize the desired target quantities.

  13. Persistence of RSV promotes proliferation and epithelial-mesenchymal transition of bronchial epithelial cells through Nodal signaling.

    PubMed

    Xiang, Zhao; Liang, Zhang; Yanfeng, Huang; Leitao, Kang

    2017-10-01

    Nodal may play an important role in the development of cancers. The present study was designed to determine the effects of Nodal induced by respiratory syncytial virus (RSV) infection on the occurrence and development of lung cancer and the underlying mechanisms. After verification of RSV infection by observation of cytopathic effect and indirect immunofluorescence, real-time PCR, Western blot and methylation assays were used to verify the influence of RSV on Nodal expression. Then, a Nodal overexpressed vector was constructed and the effects of Nodal on the proliferation and apoptosis of bronchial epithelial cells (BECs) and epithelial-mesenchymal transition (EMT) were assayed by flow cytometry and Western blot, respectively. Moreover, Lefty and pSmad2/3 were assayed by Western blot and Cyclin D1, CDK4, c-myc and Bcl-2 induced by Nodal overepression or RSV infection were also assayed by real-time PCR. The results showed that Nodal over expression and demethylation of the promoter were observed in BECs after RSV infection. Activation of Nodal promoted proliferation, colony formation and EMT and inhibited apoptosis of BECs. Nodal also promoted malignant change by promoting expression of cyclin D1 and related-dependent kinase and inhibiting apoptosis. Besides, RSV infection inhibited Lefty expression and promoted the activation of pSmad2/3. RSV also promoted Cyclin D1, CDK4, c-myc and Bcl-2 expression through the activation of pSmad2/3. Our data showed that persistence of RSV promoted the proliferation, epithelial-mesenchymal transition and expression of oncogenes through Nodal signaling, which may be associated with the occurrence and development of lung cancers.

  14. Childhood nodal marginal zone lymphoma with unusual clinicopathologic and cytogenetic features for the pediatric variant: a case report.

    PubMed

    Aqil, Barina; Merritt, Brian Y; Elghetany, M Tarek; Kamdar, Kala Y; Lu, Xinyan Y; Curry, Choladda V

    2015-01-01

    Nodal marginal zone lymphoma (NMZL) is a B-cell lymphoma that shares morphologic and immunophenotypic features with extranodal and splenic marginal zone lymphomas but lacks extranodal or splenic involvement at presentation. NMZL occurs mostly in adults with no sex predilection, at advanced stage (III or IV), with frequent relapses and a high incidence of tumoral genetic abnormalities including trisomies 3 and 18 and gain of 7q. Pediatric NMZL, however, is a rare but distinct variant of NMZL with characteristic features including male predominance, asymptomatic and localized (stage I) disease, low relapse rates with excellent outcomes, and a lower incidence of essentially similar genetic aberrations compared to adult NMZL. Here we describe a unique case of childhood NMZL with unusual clinicopathologic features for the pediatric variant including generalized lymphadenopathy, high-stage disease with persistence after therapy, unusual immunophenotype (CD5, CD23, and BCL6 positive), and unique chromosomal abnormalities including monosomy 20 and add(10)(p11.2).

  15. Emergent loop-nodal s(±)-wave superconductivity in CeCu(2)Si(2): similarities to the iron-based superconductors.

    PubMed

    Ikeda, Hiroaki; Suzuki, Michi-To; Arita, Ryotaro

    2015-04-10

    Heavy-fermion superconductors are prime candidates for novel electron-pairing states due to the spin-orbital coupled degrees of freedom and electron correlations. Superconductivity in CeCu_{2}Si_{2} discovered in 1979, which is a prototype of unconventional (non-BCS) superconductors in strongly correlated electron systems, still remains unsolved. Here we provide the first report of superconductivity based on the advanced first-principles theoretical approach. We find that the promising candidate is an s_{±}-wave state with loop-shaped nodes on the Fermi surface, different from the widely expected line-nodal d-wave state. The dominant pairing glue is magnetic but high-rank octupole fluctuations. This system shares the importance of multiorbital degrees of freedom with the iron-based superconductors. Our findings reveal not only the long-standing puzzle in this material, but also urge us to reconsider the pairing states and mechanisms in all heavy-fermion superconductors.

  16. Extended Field Intensity Modulated Radiation Therapy With Concomitant Boost for Lymph Node–Positive Cervical Cancer: Analysis of Regional Control and Recurrence Patterns in the Positron Emission Tomography/Computed Tomography Era

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vargo, John A.; Kim, Hayeon; Choi, Serah

    Purpose: Positron emission tomography/computed tomography (PET/CT) is commonly used for nodal staging in locally advanced cervical cancer; however the false negative rate for para-aortic disease are 20% to 25% in PET-positive pelvic nodal disease. Unless surgically staged, pelvis-only treatment may undertreat para-aortic disease. We have treated patients with PET-positive nodes with extended field intensity modulated radiation therapy (IMRT) to address the para-aortic region prophylactically with concomitant boost to involved nodes. The purpose of this study was to assess regional control rates and recurrence patterns. Methods and Materials: Sixty-one patients with cervical cancer (stage IBI-IVA) diagnosed from 2003 to 2012 withmore » PET-avid pelvic nodes treated with extended field IMRT (45 Gy in 25 fractions with concomitant boost to involved nodes to a median of 55 Gy in 25 fractions) with concurrent cisplatin and brachytherapy were retrospectively analyzed. The nodal location was pelvis-only in 41 patients (67%) and pelvis + para-aortic in 20 patients (33%). There were a total of 179 nodes, with a median number of positive nodes of 2 (range, 1-16 nodes) per patient and a median nodal size of 1.8 cm (range, 0.7-4.5 cm). Response was assessed by PET/CT at 12 to 16 weeks. Results: Complete clinical and imaging response at the first follow-up visit was seen in 77% of patients. At a mean follow-up time of 29 months (range, 3-116 months), 8 patients experienced recurrence. The sites of persistent/recurrent disease were as follows: cervix 10 (16.3%), regional nodes 3 (4.9%), and distant 14 (23%). The rate of para-aortic failure in patients with pelvic-only nodes was 2.5%. There were no significant differences in recurrence patterns by the number/location of nodes, largest node size, or maximum node standardized uptake value. The rate of late grade 3+ adverse events was 4%. Conclusions: Extended field IMRT was well tolerated and resulted in low regional recurrence in node-positive cervical cancer. The dose of 55 Gy in 25 fractions was effective in eradicating disease in involved nodes, with acceptable late adverse events. Distant metastasis is the predominant mode of failure, and the OUTBACK trial may challenge the presented paradigms.« less

  17. TGFβ signaling in establishing left-right asymmetry.

    PubMed

    Shiratori, Hidetaka; Hamada, Hiroshi

    2014-08-01

    Two TGFβ-related proteins, Nodal and Lefty, are asymmetrically expressed and play central roles in establishing left-right (L-R) asymmetry of our body. Nodal acts as a left-side determinant whereas Lefty restricts Nodal activity to the left side by acting as a feedback inhibitor of Nodal. While the mechanism for symmetry breaking is variable among animals, the pair of Nodal and Lefty has a conserved role in the L-R asymmetry pathway. Function and regulation of Nodal and Lefty have been revealed in the last decades, but in this review we summarize the role of TGFβ-related proteins together with more recent findings. We mainly discuss observations made with mouse embryos, unless indicated otherwise. Copyright © 2014. Published by Elsevier Ltd.

  18. Prognostic Value of National Comprehensive Cancer Network Lung Cancer Resection Quality Parameters

    PubMed Central

    Osarogiagbon, Raymond U.; Ray, Meredith A.; Faris, Nicholas R.; Div, M.; Smeltzer, Matthew P.; Stat, M.; Fehnel, Carrie; Houston-Harris, Cheryl; Signore, Raymond S.; McHugh, Laura M.; Levy, Paul; Wiggins, Lynn; Sachdev, Vishal; Robbins, Edward T.

    2017-01-01

    Background The National Comprehensive Cancer Network (NCCN) surgical resection guidelines for non-small-cell lung cancer (NSCLC) recommend anatomic resection, negative margins, examination of hilar/intrapulmonary lymph nodes, and examination of 3 or more mediastinal nodal stations. We examined the survival impact of these guidelines. Methods Population-based observational study using patient-level data from all curative-intent NSCLC resections from 2004–2013 at 11 institutions in 4 contiguous Dartmouth Hospital Referral Regions in 3 US states. We used an adjusted Cox proportional hazards model to assess the overall survival impact of attaining NCCN guidelines. Results Of 2,429 eligible resections,91% were anatomic, 94% had negative margins, 51% sampled hilar nodes, and 26% examined three or more mediastinal nodal stations. Only 17% of resections met all four criteria, however there was a significant increasing trend from 2% in 2004 to 39% in 2013 (p<0.001). Compared to patients whose surgery missed one or more parameters, the hazard ratio for patients whose surgery met all four criteria was 0.71 (95% confidence interval: 0.59–0.86, p<0.001). Margin status and the nodal staging parameters were most strongly linked with survival. Conclusions Attainment of NCCN surgical quality guidelines was low, but improving, over the past decade in this cohort from a high lung cancer mortality region of the US. The NCCN quality criteria, especially the nodal examination criteria, were strongly associated with survival. The quality of nodal examination should be a focus of quality improvement in NSCLC care. PMID:28366464

  19. Recurrence in Region of Spared Parotid Gland After Definitive Intensity-Modulated Radiotherapy for Head and Neck Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Cannon, Donald M.; Lee, Nancy Y.

    2008-03-01

    Purpose: To discuss the implications of three examples of periparotid recurrence after definitive intensity-modulated radiotherapy (IMRT) for head and neck cancer (HNC). Methods and Materials: We present 3 patients with HNC who underwent definitive IMRT with concurrent chemotherapy and later had treatment failure in or near a spared parotid gland. Two patients had bilateral multilevel nodal disease, and all had Level II nodal disease ipsilateral to the site of recurrence. The patients were treated using dose-painting IMRT with a dose of 70 Gy to the gross tumor volume and 59.4 Gy or 54 Gy to the high-risk or low-risk clinicalmore » tumor volume, respectively. The parotid glands were spared bilaterally. The patients had not undergone any surgical treatment for HNC before radiotherapy. Results: All patients had treatment failure in the region of a spared parotid gland. Failure in the 2 patients with bilateral multilevel nodal involvement occurred in the periparotid lymph nodes. The third patient developed a dermal metastasis near the tail of a spared parotid gland. On pretreatment imaging, the 2 patients with nodal failure had small nonspecific periparotid nodules that showed no hypermetabolic activity on positron emission tomography. Conclusion: For HNC patients receiving definitive IMRT, nonspecific positron emission tomography-negative periparotid nodules on pretreatment imaging should raise the index of suspicion for subclinical disease in the presence of multilevel or Level II nodal metastases. Additional evaluation of such nodules might be indicated before sparing the ipsilateral parotid gland.« less

  20. Intensity-Modulated Radiation Therapy for the Treatment of Squamous Cell Anal Cancer With Para-aortic Nodal Involvement

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hodges, Joseph C.; Das, Prajnan, E-mail: PrajDas@mdanderson.or; Eng, Cathy

    2009-11-01

    Purpose: To determine the rates of toxicity, locoregional control, distant control, and survival in anal cancer patients with para-aortic nodal involvement, treated with intensity-modulated radiotherapy (IMRT) and concurrent chemotherapy at a single institution. Methods and Materials: Between 2001 and 2007, 6 patients with squamous cell anal cancer and para-aortic nodal involvement were treated with IMRT and concurrent infusional 5-fluorouracil and cisplatin. The primary tumor was treated with a median dose of 57.5 Gy (range, 54-60 Gy), involved para-aortic, pelvic, and inguinal lymph nodes were treated with a median dose of 55 Gy (range, 50.5-55 Gy), and noninvolved nodal regions weremore » treated with a median dose of 45 Gy (range, 43.5-45 Gy). Results: After a median follow-up of 25 months, none of the patients had a recurrence at the primary tumor, pelvic/inguinal nodes, or para-aortic nodes, whereas 2 patients developed distant metastases to the liver. Four of the 6 patients are alive. The 3-year actuarial locoregional control, distant control, and overall survival rates were 100%, 56%, and 63%, respectively. Four of the 6 patients developed Grade 3 acute gastrointestinal toxicity during chemoradiation. Conclusions: Intensity-modulated radiotherapy and concurrent chemotherapy could potentially serve as definitive therapy in anal cancer patients with para-aortic nodal involvement. Adjuvant chemotherapy may be indicated in these patients, as demonstrated by the distant failure rates. These patients need to be followed carefully because of the potential for treatment-related toxicities.« less

  1. Cerberus-Nodal-Lefty-Pitx signaling cascade controls left-right asymmetry in amphioxus.

    PubMed

    Li, Guang; Liu, Xian; Xing, Chaofan; Zhang, Huayang; Shimeld, Sebastian M; Wang, Yiquan

    2017-04-04

    Many bilaterally symmetrical animals develop genetically programmed left-right asymmetries. In vertebrates, this process is under the control of Nodal signaling, which is restricted to the left side by Nodal antagonists Cerberus and Lefty. Amphioxus, the earliest diverging chordate lineage, has profound left-right asymmetry as a larva. We show that Cerberus , Nodal , Lefty , and their target transcription factor Pitx are sequentially activated in amphioxus embryos. We then address their function by transcription activator-like effector nucleases (TALEN)-based knockout and heat-shock promoter (HSP)-driven overexpression. Knockout of Cerberus leads to ectopic right-sided expression of Nodal , Lefty , and Pitx , whereas overexpression of Cerberus represses their left-sided expression. Overexpression of Nodal in turn represses Cerberus and activates Lefty and Pitx ectopically on the right side. We also show Lefty represses Nodal , whereas Pitx activates Nodal These data combine in a model in which Cerberus determines whether the left-sided gene expression cassette is activated or repressed. These regulatory steps are essential for normal left-right asymmetry to develop, as when they are disrupted embryos may instead form two phenotypic left sides or two phenotypic right sides. Our study shows the regulatory cassette controlling left-right asymmetry was in place in the ancestor of amphioxus and vertebrates. This includes the Nodal inhibitors Cerberus and Lefty, both of which operate in feedback loops with Nodal and combine to establish asymmetric Pitx expression. Cerberus and Lefty are missing from most invertebrate lineages, marking this mechanism as an innovation in the lineage leading to modern chordates.

  2. Preoperative predictors of occult nodal disease in cT1N0 oral cavity squamous cell carcinoma: Review of 2623 cases.

    PubMed

    Zhan, Kevin Y; Morgan, Patrick F; Neskey, David M; Kim, Joanne J; Huang, Andrew T; Garrett-Mayer, Elizabeth; Day, Terry A

    2018-05-14

    Nodal disease predicts survival in oral cavity squamous cell carcinoma (SCC). Currently, no large studies on predictors of occult nodal disease in cT1N0 oral cavity SCC exist. The National Cancer Database (NCDB) review for cT1N0 oral cavity SCC with surgical resection and elective neck dissection (END). The number of patients found with occult nodal disease was 2623 (15.1%). In multivariable regression, female sex and tumor differentiation predict occult nodal disease. Occult nodal disease incidence was 5.9% in well-differentiated tumors, 17.4% in moderately differentiated tumors, and 28.5% in poorly differentiated tumor (P < .001). Women with oral tongue tumors had higher occult nodal disease (19.1%) than men (12%; P = .001). Adjusted odds ratios (aORs) for occult nodal disease in women were: aOR 1.26; 95% confidence interval (CI) 1.01-1.59; P = .045; moderately differentiated aOR 3.52; 95% CI 2.47-5.01; P < .001; and poorly differentiated aOR 6.25; 95% CI 4.17-9.38; P < .001. Sex and tumor differentiation significantly predict occult nodal disease. END is recommended for all moderately and poorly differentiated cT1N0 oral cavity SCC, regardless of the depth of invasion. One can consider not performing END in well-differentiated tumors. © 2018 Wiley Periodicals, Inc.

  3. Activin- and Nodal-related factors control antero-posterior patterning of the zebrafish embryo.

    PubMed

    Thisse, B; Wright, C V; Thisse, C

    2000-01-27

    Definition of cell fates along the dorso-ventral axis depends on an antagonistic relationship between ventralizing transforming growth factor-beta superfamily members, the bone morphogenetic proteins and factors secreted from the dorsal organizer, such as Noggin and Chordin. The extracellular binding of the last group to the bone morphogenetic proteins prevents them from activating their receptors, and the relative ventralizer:antagonist ratio is thought to specify different dorso-ventral cell fates. Here, by taking advantage of a non-genetic interference method using a specific competitive inhibitor, the Lefty-related gene product Antivin, we provide evidence that cell fate along the antero-posterior axis of the zebrafish embryo is controlled by the morphogenetic activity of another transforming growth factor-beta superfamily subgroup--the Activin and Nodal-related factors. Increasing antivin doses progressively deleted posterior fates within the ectoderm, eventually resulting in the removal of all fates except forebrain and eyes. In contrast, overexpression of activin or nodal-related factors converted ectoderm that was fated to be forebrain into more posterior ectodermal or mesendodermal fates. We propose that modulation of intercellular signalling by Antivin/Activin and Nodal-related factors provides a mechanism for the graded establishment of cell fates along the antero-posterior axis of the zebrafish embryo.

  4. Nodal signalling and asymmetry of the nervous system

    PubMed Central

    Signore, Iskra A.; Palma, Karina

    2016-01-01

    The role of Nodal signalling in nervous system asymmetry is still poorly understood. Here, we review and discuss how asymmetric Nodal signalling controls the ontogeny of nervous system asymmetry using a comparative developmental perspective. A detailed analysis of asymmetry in ascidians and fishes reveals a critical context-dependency of Nodal function and emphasizes that bilaterally paired and midline-unpaired structures/organs behave as different entities. We propose a conceptual framework to dissect the developmental function of Nodal as asymmetry inducer and laterality modulator in the nervous system, which can be used to study other types of body and visceral organ asymmetries. Using insights from developmental biology, we also present novel evolutionary hypotheses on how Nodal led the evolution of directional asymmetry in the brain, with a particular focus on the epithalamus. We intend this paper to provide a synthesis on how Nodal signalling controls left–right asymmetry of the nervous system. This article is part of the themed issue ‘Provocative questions in left–right asymmetry’. PMID:27821531

  5. Analysis of nodal coverage utilizing image guided radiation therapy for primary gynecologic tumor volumes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ahmed, Faisal; Loma Linda University Medical Center, Department of Radiation Oncology, Loma Linda, CA; Sarkar, Vikren

    Purpose: To evaluate radiation dose delivered to pelvic lymph nodes, if daily Image Guided Radiation Therapy (IGRT) was implemented with treatment shifts based on the primary site (primary clinical target volume [CTV]). Our secondary goal was to compare dosimetric coverage with patient outcomes. Materials and methods: A total of 10 female patients with gynecologic malignancies were evaluated retrospectively after completion of definitive intensity-modulated radiation therapy (IMRT) to their pelvic lymph nodes and primary tumor site. IGRT consisted of daily kilovoltage computed tomography (CT)-on-rails imaging fused with initial planning scans for position verification. The initial plan was created using Varian's Eclipsemore » treatment planning software. Patients were treated with a median radiation dose of 45 Gy (range: 37.5 to 50 Gy) to the primary volume and 45 Gy (range: 45 to 64.8 Gy) to nodal structures. One IGRT scan per week was randomly selected from each patient's treatment course and re-planned on the Eclipse treatment planning station. CTVs were recreated by fusion on the IGRT image series, and the patient's treatment plan was applied to the new image set to calculate delivered dose. We evaluated the minimum, maximum, and 95% dose coverage for primary and nodal structures. Reconstructed primary tumor volumes were recreated within 4.7% of initial planning volume (0.9% to 8.6%), and reconstructed nodal volumes were recreated to within 2.9% of initial planning volume (0.01% to 5.5%). Results: Dosimetric parameters averaged less than 10% (range: 1% to 9%) of the original planned dose (45 Gy) for primary and nodal volumes on all patients (n = 10). For all patients, ≥99.3% of the primary tumor volume received ≥ 95% the prescribed dose (V95%) and the average minimum dose was 96.1% of the prescribed dose. In evaluating nodal CTV coverage, ≥ 99.8% of the volume received ≥ 95% the prescribed dose and the average minimum dose was 93%. In evaluating individual IGRT sessions, we found that 6 patients had an estimated minimal nodal CTV dose less than 90% (range: 78 to 99%) of that planned. With a median follow-up of 42.5 months, 2 patients experienced systemic disease progression at an average of 19.6 months. One patient was found to have a local or regional failure with an average follow-up of 42 months. Conclusion: Using only 3 dimensional IGRT corrections in gynecological radiation allows excellent coverage of the primary target volume and good average nodal CTV coverage. If IGRT corrections are based on alignment to the primary tumor volume, and is only able to be corrected in 3 degrees, this can create situations in which nodal volumes may be under dosed. Utilizing multiple IGRT sessions appears to average out dose discrepancies over the course of treatment. The implication of underdosing in a single IGRT session needs further evaluation in future studies. Based on the concern of minimum dose to a nodal target volume, these findings may signal caution when using IGRT and IMRT in gynecological radiation patients. Possible techniques to overcome this situation may include averaging shifts between tumor and nodal volume, use of a treatment couch with 6° of freedom, deformable registration, or adaptive planning.« less

  6. Hopf-link topological nodal-loop semimetals

    NASA Astrophysics Data System (ADS)

    Zhou, Yao; Xiong, Feng; Wan, Xiangang; An, Jin

    2018-04-01

    We construct a generic two-band model which can describe topological semimetals with multiple closed nodal loops. All the existing multi-nodal-loop semimetals, including the nodal-net, nodal-chain, and Hopf-link states, can be examined within the same framework. Based on a two-nodal-loop model, the corresponding drumhead surface states for these topologically different bulk states are studied and compared with each other. The connection of our model with Hopf insulators is also discussed. Furthermore, to identify experimentally these topologically different semimetal states, especially to distinguish the Hopf-link from unlinked ones, we also investigate their Landau levels. It is found that the Hopf-link state can be characterized by the existence of a quadruply degenerate zero-energy Landau band, regardless of the direction of the magnetic field.

  7. pN0(i+) Breast Cancer: Treatment Patterns, Locoregional Recurrence, and Survival Outcomes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Karam, Irene; Breast Cancer Outcomes Unit, British Columbia Cancer Agency, Vancouver, BC; Lesperance, Maria F.

    Purpose: To examine treatment patterns, recurrence, and survival outcomes in patients with pN0(i+) breast cancer. Methods and Materials: Subjects were 5999 women with AJCC (6th edition) pT1-3, pN0-N1a, M0 breast cancer diagnosed between 2003 and 2006. Of these, 4342 (72%) had pN0, 96 (2%) had pN0(i+), 349 (6%) had pNmic (micrometastases >0.2 mm to ≤2 mm), and 1212 (20%) had pN1a (1-3 positive macroscopic nodes) disease. Treatment characteristics and 5-year Kaplan-Meier local recurrence, regional recurrence (RR), locoregional recurrence (LRR), and overall survival were compared between nodal subgroups. Multivariable analysis was performed using Cox regression modeling. A 1:3 case-match analysis examinedmore » outcomes in pN0(i+) cases compared with pN0 controls matched for similar tumor and treatment characteristics. Results: Median follow-up was 4.8 years. Adjuvant systemic therapy use increased with nodal stage: 81%, 92%, 95%, and 94% in pN0, pN0(i+), pNmic, and pN1a disease, respectively (P<.001). Nodal radiation therapy (RT) use also increased with nodal stage: 1.7% in pN0, 27% in pN0(i+), 33% in pNmic, and 63% in pN1a cohorts (P<.001). Five-year Kaplan-Meier outcomes in pN0 versus pN0(i+) cases were as follows: local recurrence 1.7% versus 3.7% (P=.20), RR 0.5% versus 2.2% (P=.02), and LRR 2.1% versus 5.8% (P=.02). There were no RR events in 26 patients with pN0(i+) disease who received nodal RT and 2 RR events in 70 patients who did not receive nodal RT. On multivariable analysis, pN0(i+) was not associated with worse locoregional control or survival. On case-match analysis, LRR and overall survival were similar between pN0(i+) and matched pN0 counterparts. Conclusions: Nodal involvement with isolated tumor cells is not a significant prognostic factor for LRR or survival in this study's multivariable and case-match analyses. These data do not support the routine use of nodal RT in the setting of pN0(i+) disease. Prospective studies are needed to define optimal locoregional management for women with pN0(i+) breast cancer.« less

  8. De-Aliasing Through Over-Integration Applied to the Flux Reconstruction and Discontinuous Galerkin Methods

    NASA Technical Reports Server (NTRS)

    Spiegel, Seth C.; Huynh, H. T.; DeBonis, James R.

    2015-01-01

    High-order methods are quickly becoming popular for turbulent flows as the amount of computer processing power increases. The flux reconstruction (FR) method presents a unifying framework for a wide class of high-order methods including discontinuous Galerkin (DG), Spectral Difference (SD), and Spectral Volume (SV). It offers a simple, efficient, and easy way to implement nodal-based methods that are derived via the differential form of the governing equations. Whereas high-order methods have enjoyed recent success, they have been known to introduce numerical instabilities due to polynomial aliasing when applied to under-resolved nonlinear problems. Aliasing errors have been extensively studied in reference to DG methods; however, their study regarding FR methods has mostly been limited to the selection of the nodal points used within each cell. Here, we extend some of the de-aliasing techniques used for DG methods, primarily over-integration, to the FR framework. Our results show that over-integration does remove aliasing errors but may not remove all instabilities caused by insufficient resolution (for FR as well as DG).

  9. Lymph node involvement in gastric cancer for different tumor sites and T stage: Italian Research Group for Gastric Cancer (IRGGC) experience.

    PubMed

    Di Leo, Alberto; Marrelli, Daniele; Roviello, Franco; Bernini, Marco; Minicozzi, AnnaMaria; Giacopuzzi, Simone; Pedrazzani, Corrado; Baiocchi, Luca Gian; de Manzoni, Giovanni

    2007-09-01

    The aim of lymphadenectomy is to clear all the metastatic nodes achieving a complete removal of the tumor; nevertheless, its role in gastric cancer has been very much debated. The frequency of node metastasis in each lymphatic station according to the International Gastric Cancer Association, was studied in 545 patients who underwent D2 or D3 lymphadenectomy from June 1988 to December 2002. Upper third early cancers have shown an involvement of N2 celiac nodes in 25%. In advanced cancers, there was a high frequency of metastasis in the right gastroepiploic (from 10% in T2 to 50% in T4) and in the paraaortic nodes (26% in T2, 32% in T3, 38 % in T4). N3 left paracardial nodes involvement was observed in an important share of middle third tumors (17% in T3, 36% in T4). Splenic hilum nodes metastasis were common in T3 and T4 cancers located in the upper (39%) and middle (17%) stomach. N2 nodal involvement was frequent in lower third advanced cancers. Metastasis in M left paracardial and short gastric nodes were observed in a small percentage of cases. Given the nodal diffusion in our gastric cancer patients, extended lymphadenectomy is still a rationale to obtain radical resection.

  10. Method and apparatus for routing data in an inter-nodal communications lattice of a massively parallel computer system by dynamic global mapping of contended links

    DOEpatents

    Archer, Charles Jens [Rochester, MN; Musselman, Roy Glenn [Rochester, MN; Peters, Amanda [Rochester, MN; Pinnow, Kurt Walter [Rochester, MN; Swartz, Brent Allen [Chippewa Falls, WI; Wallenfelt, Brian Paul [Eden Prairie, MN

    2011-10-04

    A massively parallel nodal computer system periodically collects and broadcasts usage data for an internal communications network. A node sending data over the network makes a global routing determination using the network usage data. Preferably, network usage data comprises an N-bit usage value for each output buffer associated with a network link. An optimum routing is determined by summing the N-bit values associated with each link through which a data packet must pass, and comparing the sums associated with different possible routes.

  11. Method and apparatus for routing data in an inter-nodal communications lattice of a massively parallel computer system by dynamically adjusting local routing strategies

    DOEpatents

    Archer, Charles Jens; Musselman, Roy Glenn; Peters, Amanda; Pinnow, Kurt Walter; Swartz, Brent Allen; Wallenfelt, Brian Paul

    2010-03-16

    A massively parallel computer system contains an inter-nodal communications network of node-to-node links. Each node implements a respective routing strategy for routing data through the network, the routing strategies not necessarily being the same in every node. The routing strategies implemented in the nodes are dynamically adjusted during application execution to shift network workload as required. Preferably, adjustment of routing policies in selective nodes is performed at synchronization points. The network may be dynamically monitored, and routing strategies adjusted according to detected network conditions.

  12. Epstein-Barr virus-positive nodal T/NK-cell lymphoma: an analysis of 15 cases with distinct clinicopathological features.

    PubMed

    Jeon, Yoon Kyung; Kim, Jo-Heon; Sung, Ji-Youn; Han, Jae Ho; Ko, Young-Hyeh

    2015-07-01

    Nodal peripheral T-cell lymphoma, not otherwise specified, is a heterogeneous entity with variable biologic behavior. We analyze the clinicopathological features of 15 patients with Epstein-Barr virus-positive (EBV+) nodal T/NK-cell lymphoma, including 9 males and 6 females, with a median age of 64 years. All patients presented with multiple lymphadenopathy with common B symptoms (80%, 12/15) at an advanced Ann Arbor stage (III, IV) (87%, 13/15). The International Prognostic Index was high or high/intermediate in 87% (13/15) of patients, and the prognostic index for peripheral T-cell lymphoma was group 3 or 4 in 73% (11/15). Spleen and liver involvement was observed in 73% (11/15) and 60% (9/15) of patients, respectively. In contrast, extranodal involvement was infrequent, with no more than 1 site in 71% (10/15) of patients. Moreover, none had nasal lesions, and only 1 had mucocutaneous involvement. The cell lineage of EBV+ tumor cells was determined to be T cell in all except 1 patient, who was NK-cell lineage. Cytotoxic molecules were expressed in all cases, and 64% (9/14) of patients expressed the αβT-cell receptor. Moreover, most patients (67%, 10/15) showed CD8 positivity, with 2 of them being CD4CD8 double positive; the others were CD4 positive (n = 2) or CD4CD8 double negative (n = 3). The clinical course was very aggressive, with a median survival time of 3.5 months, and 10 patients died within 6 months of diagnosis. Taken together, our data demonstrate that EBV+ nodal T/NK-cell lymphoma is a distinct clinicopathological entity characterized by cytotoxic molecule expression, a frequent CD8-positive αβT-cell lineage, and a very aggressive clinical behavior. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Left-right asymmetry in the level of active Nodal protein produced in the node is translated into left-right asymmetry in the lateral plate of mouse embryos.

    PubMed

    Kawasumi, Aiko; Nakamura, Tetsuya; Iwai, Naomi; Yashiro, Kenta; Saijoh, Yukio; Belo, Jose Antonio; Shiratori, Hidetaka; Hamada, Hiroshi

    2011-05-15

    Left-right (L-R) asymmetry in the mouse embryo is generated in the node and is dependent on cilia-driven fluid flow, but how the initial asymmetry is transmitted from the node to the lateral plate has remained unknown. We have now identified a transcriptional enhancer (ANE) in the human LEFTY1 gene that exhibits marked L>R asymmetric activity in perinodal cells of the mouse embryo. Dissection of ANE revealed that it is activated in the perinodal cells on the left side by Nodal signaling, suggesting that Nodal activity in the node is asymmetric at a time when Nodal expression is symmetric. Phosphorylated Smad2/3 (pSmad2) indeed manifested an L-R asymmetric distribution at the node, being detected in perinodal cells preferentially on the left side. This asymmetry in pSmad2 distribution was found to be generated not by unidirectional transport of Nodal but rather as a result of LR distribution of active Nodal in the node is translated into the asymmetry in LPM. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. Occult Nodal Disease Prevalence and Distribution in Recurrent Laryngeal Cancer Requiring Salvage Laryngectomy.

    PubMed

    Birkeland, Andrew C; Rosko, Andrew J; Issa, Mohamad R; Shuman, Andrew G; Prince, Mark E; Wolf, Gregory T; Bradford, Carol R; McHugh, Jonathan B; Brenner, J Chad; Spector, Matthew E

    2016-03-01

    The indications for neck dissection concurrent with salvage laryngectomy in the clinically N0 setting remain unclear. Our goals were to determine the prevalence of occult nodal disease, analyze nodal disease distribution patterns, and identify predictors of occult nodal disease in a salvage laryngectomy cohort. Case series with planned data collection. Tertiary academic center. Patients with persistent or recurrent laryngeal squamous cell carcinoma (LSCC) after radiation/chemoradiation failure undergoing salvage laryngectomy with neck dissection. We analyzed a single-institution retrospective case series of patients between 1997 and 2014 and identified those who had clinically N0 (cN0) necks (n = 203). Clinical and pathologic data, including nodal prevalence and distribution, were collected and statistical analyses performed. Overall, cN0 necks had histologically positive occult nodes in 17% (n = 35) of cases. Univariate predictors of occult nodal positivity included recurrent T4 stage (34% T4 vs 12% non-T4; P = .0003) and supraglottic subsite (28% supraglottic vs 10% nonsupraglottic; P = .0006). Histologically positive nodes associated with supraglottic primaries were most frequently positive in ipsilateral levels II and III (17% and 16%). Positive nodes for glottic LSCC were most frequently positive in the ipsilateral and contralateral paratracheal nodes (11% and 9%). Histologically positive occult nodes are identified in 17% of cN0 patients undergoing salvage laryngectomy with neck dissection. Occult nodal disease varies in frequency and distribution based on tumor subsite. Predictors of high (>20%) occult nodal positivity include T4 tumors and supraglottic subsite. In glottic LSCC, the most frequent sites of occult nodal disease are the paratracheal nodal basins. © American Academy of Otolaryngology—Head and Neck Surgery Foundation 2016.

  15. Left-right asymmetry specification in amphioxus: review and prospects.

    PubMed

    Soukup, Vladimir

    2017-01-01

    Extant bilaterally symmetrical animals usually show asymmetry in the arrangement of their inner organs. However, the exaggerated left-right (LR) asymmetry in amphioxus represents a true peculiarity among them. The amphioxus larva shows completely disparate fates of left and right body sides, so that organs associated with pharynx are either positioned exclusively on the left or on the right side. Moreover, segmented paraxial structures such as muscle blocks and their neuronal innervation show offset arrangement between the sides making it difficult to propose any explanation or adaptivity to larval and adult life. First LR asymmetries can be traced back to an early embryonic period when morphological asymmetries are preceded by molecular asymmetries driven by the action of the Nodal signaling pathway. This review sums up recent advances in understanding LR asymmetry specification in amphioxus and proposes upstream events that may regulate asymmetric Nodal signaling. These events include the presence of the vertebrate-like LR organizer and a cilia-driven fluid flow that may be involved in the breaking of bilateral symmetry. The upstream pathways comprising the ion flux, Delta/Notch, Wnt/β-catenin and Wnt/PCP are hypothesized to regulate both formation of the LR organizer and expression of the downstream Nodal signaling pathway genes. These suggestions are in line with what we know from vertebrate and ambulacrarian LR axis specification and are directly testable by experimental manipulations. Thanks to the phylogenetic position of amphioxus, the proposed mechanisms may be helpful in understanding the evolution of LR axis specification across deuterostomes.

  16. Modern Radiation Therapy for Nodal Non-Hodgkin Lymphoma—Target Definition and Dose Guidelines From the International Lymphoma Radiation Oncology Group

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Illidge, Tim, E-mail: Tim.Illidge@ics.manchester.ac.uk; Specht, Lena; Yahalom, Joachim

    2014-05-01

    Radiation therapy (RT) is the most effective single modality for local control of non-Hodgkin lymphoma (NHL) and is an important component of therapy for many patients. Many of the historic concepts of dose and volume have recently been challenged by the advent of modern imaging and RT planning tools. The International Lymphoma Radiation Oncology Group (ILROG) has developed these guidelines after multinational meetings and analysis of available evidence. The guidelines represent an agreed consensus view of the ILROG steering committee on the use of RT in NHL in the modern era. The roles of reduced volume and reduced doses aremore » addressed, integrating modern imaging with 3-dimensional planning and advanced techniques of RT delivery. In the modern era, in which combined-modality treatment with systemic therapy is appropriate, the previously applied extended-field and involved-field RT techniques that targeted nodal regions have now been replaced by limiting the RT to smaller volumes based solely on detectable nodal involvement at presentation. A new concept, involved-site RT, defines the clinical target volume. For indolent NHL, often treated with RT alone, larger fields should be considered. Newer treatment techniques, including intensity modulated RT, breath holding, image guided RT, and 4-dimensional imaging, should be implemented, and their use is expected to decrease significantly the risk for normal tissue damage while still achieving the primary goal of local tumor control.« less

  17. Adenoid cystic carcinoma of the external ear: a population based study.

    PubMed

    Green, Ross W; Megwalu, Uchechukwu C

    2016-01-01

    To determine the incidence of adenoid cystic carcinoma of the external ear in the United States, and to evaluate the clinical characteristics and survival outcomes associated with the disease. Data were extracted from the Surveillance, Epidemiology, and End Results (SEER) 18 Database of the National Cancer Institute. The study cohort included patients diagnosed with adenoid cystic carcinoma of the external ear from 1973 to 2012. The incidence of adenoid cystic carcinoma of the external ear was 0.004 per 100,000. The SEER database identified 66 patients meeting the inclusion criteria. Nodal metastasis was noted in 13.1% of patients, while 7.9% had distant metastasis. Distant metastasis was associated with worse overall survival (HR 10.18). However, nodal metastasis had no impact on overall survival (HR 0.15, p = 0.09). Surgery alone was associated with improved overall survival (HR 0.26), compared with combination surgery and radiotherapy, while radiotherapy alone was associated with worse overall survival (HR 20.12). Increasing age (HR 1.12) and black race (HR 6.83) were associated with worse overall survival, while female sex (HR 0.26) was associated with improved overall survival. ACC of the external ear is rare. Distant metastasis is a poor prognostic factor. However, nodal metastasis does not appear to impact survival. Advanced age, black race, and male sex are also poor prognostic factors. Surgical resection alone is associated with better survival than combination surgical resection and radiation, or radiotherapy alone. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Efficient Meshfree Large Deformation Simulation of Rainfall Induced Soil Slope Failure

    NASA Astrophysics Data System (ADS)

    Wang, Dongdong; Li, Ling

    2010-05-01

    An efficient Lagrangian Galerkin meshfree framework is presented for large deformation simulation of rainfall-induced soil slope failure. Detailed coupled soil-rainfall seepage equations are given for the proposed formulation. This nonlinear meshfree formulation is featured by the Lagrangian stabilized conforming nodal integration method where the low cost nature of nodal integration approach is kept and at the same time the numerical stability is maintained. The initiation and evolution of progressive failure in the soil slope is modeled by the coupled constitutive equations of isotropic damage and Drucker-Prager pressure-dependent plasticity. The gradient smoothing in the stabilized conforming integration also serves as a non-local regularization of material instability and consequently the present method is capable of effectively capture the shear band failure. The efficacy of the present method is demonstrated by simulating the rainfall-induced failure of two typical soil slopes.

  19. Fourier-Accelerated Nodal Solvers (FANS) for homogenization problems

    NASA Astrophysics Data System (ADS)

    Leuschner, Matthias; Fritzen, Felix

    2017-11-01

    Fourier-based homogenization schemes are useful to analyze heterogeneous microstructures represented by 2D or 3D image data. These iterative schemes involve discrete periodic convolutions with global ansatz functions (mostly fundamental solutions). The convolutions are efficiently computed using the fast Fourier transform. FANS operates on nodal variables on regular grids and converges to finite element solutions. Compared to established Fourier-based methods, the number of convolutions is reduced by FANS. Additionally, fast iterations are possible by assembling the stiffness matrix. Due to the related memory requirement, the method is best suited for medium-sized problems. A comparative study involving established Fourier-based homogenization schemes is conducted for a thermal benchmark problem with a closed-form solution. Detailed technical and algorithmic descriptions are given for all methods considered in the comparison. Furthermore, many numerical examples focusing on convergence properties for both thermal and mechanical problems, including also plasticity, are presented.

  20. Immunocompromised patients with metastatic cutaneous nodal squamous cell carcinoma of the head and neck: Poor outcome unrelated to the index lesion.

    PubMed

    Lam, Johnson K S; Sundaresan, Puma; Gebski, Val; Veness, Michael J

    2018-05-01

    Immunocompromised patients with metastatic cutaneous nodal head and neck squamous cell carcinoma (HNSCC) have worse outcomes compared to the immunocompetent. The purpose of this study was to investigate the characteristics of the primary cutaneous squamous cell carcinoma (SCC), nodal pathology, and outcome between these 2 groups. Analysis of a prospective database was performed. A 2:1 pooled analysis selected 46 immunocompetent patients matched with 23 immunocompromised patients. Overall survival (OS) and relapse-free survival (RFS) were calculated using the Kaplan-Meier method. No significant difference was found in the primary tumor characteristics between the 2 groups. In the immunocompromised group, RFS (hazard ratio [HR] 2.70; P = .01) and OS (HR 2.32; P = .04) were significantly worse. Extracapsular spread was present in 100% of the immunocompromised patients. No significant difference was identified in the primary cutaneous SCC between the immunocompetent and immunocompromised patients. Immunosuppression predicted worse outcome. © 2018 Wiley Periodicals, Inc.

  1. Dynamic characteristics of two new vibration modes of the disk-shell shaped gear

    NASA Astrophysics Data System (ADS)

    Yan, Litang; Qiu, Shijung; Gao, Xiangqung

    1992-10-01

    Two new vibration modes of the disk-shell-shaped big medium gears placed on three separate medium shafts of a turboprop engine have been found. They have the same nodal diameters as the conventional ones, but their frequencies are higher. The tooth ring vibrates both radially and axially and has greater deflection than the gear hub. The resonance of these two new nodal diameter modes is much more dangerous than that of the conventional nodal diameter modes. Moreover, they occur nearly at the upper and the lower bounds of the gear operating speed range. A special detuning method is developed for removing the resonance of these two new modes out of the upper and the lower bounds, respectively, and the effectiveness of the damping rings in this case has been researched. The vibration responses measured on the reductor casing have been then reduced to a quite low level after the damping rings were applied to the three big medium gears.

  2. Decompositions of injection patterns for nodal flow allocation in renewable electricity networks

    NASA Astrophysics Data System (ADS)

    Schäfer, Mirko; Tranberg, Bo; Hempel, Sabrina; Schramm, Stefan; Greiner, Martin

    2017-08-01

    The large-scale integration of fluctuating renewable power generation represents a challenge to the technical and economical design of a sustainable future electricity system. In this context, the increasing significance of long-range power transmission calls for innovative methods to understand the emerging complex flow patterns and to integrate price signals about the respective infrastructure needs into the energy market design. We introduce a decomposition method of injection patterns. Contrary to standard flow tracing approaches, it provides nodal allocations of link flows and costs in electricity networks by decomposing the network injection pattern into market-inspired elementary import/export building blocks. We apply the new approach to a simplified data-driven model of a European electricity grid with a high share of renewable wind and solar power generation.

  3. A study of the radiative transfer equation using a spherical harmonics-nodal collocation method

    NASA Astrophysics Data System (ADS)

    Capilla, M. T.; Talavera, C. F.; Ginestar, D.; Verdú, G.

    2017-03-01

    Optical tomography has found many medical applications that need to know how the photons interact with the different tissues. The majority of the photon transport simulations are done using the diffusion approximation, but this approximation has a limited validity when optical properties of the different tissues present large gradients, when structures near the photons source are studied or when anisotropic scattering has to be taken into account. As an alternative to the diffusion model, the PL equations for the radiative transfer problem are studied. These equations are discretized in a rectangular mesh using a nodal collocation method. The performance of this model is studied by solving different 1D and 2D benchmark problems of light propagation in tissue having media with isotropic and anisotropic scattering.

  4. On equivalent resistance of electrical circuits

    NASA Astrophysics Data System (ADS)

    Kagan, Mikhail

    2015-01-01

    While the standard (introductory physics) way of computing the equivalent resistance of nontrivial electrical circuits is based on Kirchhoff's rules, there is a mathematically and conceptually simpler approach, called the method of nodal potentials, whose basic variables are the values of the electric potential at the circuit's nodes. In this paper, we review the method of nodal potentials and illustrate it using the Wheatstone bridge as an example. We then derive a closed-form expression for the equivalent resistance of a generic circuit, which we apply to a few sample circuits. The result unveils a curious interplay between electrical circuits, matrix algebra, and graph theory and its applications to computer science. The paper is written at a level accessible by undergraduate students who are familiar with matrix arithmetic. Additional proofs and technical details are provided in appendices.

  5. Dose-Painted Intensity-Modulated Radiation Therapy for Anal Cancer: A Multi-Institutional Report of Acute Toxicity and Response to Therapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kachnic, Lisa A., E-mail: lisa.kachnic@bmc.org; Department of Radiation Oncology, Massachusetts General Hospital and Harvard Medical School, Boston, MA; Tsai, Henry K.

    2012-01-01

    Purpose: Chemoradiation for anal cancer yields effective tumor control, but is associated with significant acute toxicity. We report our multi-institutional experience using dose-painted IMRT (DP-IMRT). Patients and Methods: Between August 2005 and May 2009, 43 patients were treated with DP-IMRT and concurrent chemotherapy for biopsy-proven, squamous cell carcinoma of the anal canal at two academic medical centers. DP-IMRT was prescribed as follows: T2N0: 42 Gy, 1.5 Gy/fraction (fx) to elective nodal planning target volume (PTV) and 50.4 Gy, 1.8 Gy/fx to anal tumor PTV; T3-4N0-3: 45 Gy, 1.5 Gy/fx to elective nodal PTV, and 54 Gy, 1.8 Gy/fx to themore » anal tumor and metastatic nodal PTV >3 cm with 50.4 Gy, 1.68 Gy/fx to nodal PTVs {<=}3 cm in size. Acute and late toxicity was reported by the treating physician. Actuarial analysis was performed using the Kaplan-Meier method. Results: Median age was 58 years; 67% female; 16% Stage I, 37% II; 42% III; 5% IV. Fourteen patients were immunocompromised: 21% HIV-positive and 12% on chronic immunosuppression. Median follow-up was 24 months (range, 0.6-43.5 months). Sixty percent completed chemoradiation without treatment interruption; median duration of treatment interruption was 2 days (range, 2-24 days). Acute Grade 3+ toxicity included: hematologic 51%, dermatologic 10%, gastrointestinal 7%, and genitourinary 7%. Two-year local control, overall survival, colostomy-free survival, and metastasis-free survival were 95%, 94%, 90%, and 92%, respectively. Conclusions: Dose-painted IMRT appears effective and well-tolerated as part of a chemoradiation therapy regimen for the treatment of anal canal cancer.« less

  6. Vibron and phonon hybridization in dielectric nanostructures.

    PubMed

    Preston, Thomas C; Signorell, Ruth

    2011-04-05

    Plasmon hybridization theory has been an invaluable tool in advancing our understanding of the optical properties of metallic nanostructures. Through the prism of molecular orbital theory, it allows one to interpret complex structures as "plasmonic molecules" and easily predict and engineer their electromagnetic response. However, this formalism is limited to conducting particles. Here, we present a hybridization scheme for the external and internal vibrations of dielectric nanostructures that provides a straightforward understanding of the infrared signatures of these particles through analogy to existing hybridization models of both molecular orbitals and plasmons extending the range of applications far beyond metallic nanostructures. This method not only provides a qualitative understanding, but also allows for the quantitative prediction of vibrational spectra of complex nanoobjects from well-known spectra of their primitive building blocks. The examples of nanoshells illustrate how spectral features can be understood in terms of symmetry, number of nodal planes, and scale parameters.

  7. A contemporary view of atrioventricular nodal physiology.

    PubMed

    Markowitz, Steven M; Lerman, Bruce B

    2018-06-16

    In delaying transmission of the cardiac impulse from the atria to the ventricles, the atrioventricular (AV) node serves a critical function in augmenting ventricular filling during diastole and limiting the ventricular response during atrial tachyarrhythmias. The complex structure of the nodal region, however, also provides the substrate for reentrant rhythms. Recent discoveries have elucidated the cellular basis and anatomical determinants of slow conduction in the node. Based on analysis of gap junction proteins, distinct structural components of the AV node have been defined, including the compact node, right and left inferior nodal extensions, the lower nodal bundle, and transitional tissue. Emerging evidence supports the role of the inferior nodal extensions in mediating slow pathway conduction. The most common form of reentry involving the node, slow-fast AV nodal reentrant tachycardia (AVNRT), utilizes the inferior nodal extensions for anterograde slow pathway conduction; the structures responsible for retrograde fast pathway activation in the superior septum are less well defined and likely heterogeneous. Atypical forms of AVNRT arise from circuits that activate at least one of the inferior extensions in the retrograde direction.

  8. Radiation Field Design in the ACOSOG Z0011 (Alliance) Trial

    PubMed Central

    Jagsi, Reshma; Chadha, Manjeet; Moni, Janaki; Ballman, Karla; Laurie, Fran; Buchholz, Thomas A.; Giuliano, Armando; Haffty, Bruce G.

    2014-01-01

    Purpose ACOSOG Z0011 established that axillary lymph node dissection (ALND) is unnecessary in patients with breast cancer with one to two positive sentinel lymph nodes (SLNs) who undergo lumpectomy, radiotherapy (RT), and systemic therapy. We sought to ascertain RT coverage of the regional nodes in that trial. Methods We evaluated case report forms completed 18 months after enrollment. From 2012 to 2013, we collected all available detailed RT records for central review. Results Among 605 patients with completed case report forms, 89% received whole-breast RT. Of these, 89 (15%) were recorded as also receiving treatment to the supraclavicular region. Detailed RT records were obtained for 228 patients, of whom 185 (81.1%) received tangent-only treatment. Among 142 with sufficient records to evaluate tangent height, high tangents (cranial tangent border ≤ 2 cm from humeral head) were used in 50% of patients (33 of 66) randomly assigned to ALND and 52.6% (40 of 76) randomly assigned to SLND. Of the 228 patients with records reviewed, 43 (18.9%) received directed regional nodal RT using ≥ three fields: 22 in the ALND arm and 21 in the SLND arm. Those receiving directed nodal RT had greater nodal involvement (P < .001) than those who did not. Overall, there was no significant difference between treatment arms in the use of protocol-prohibited nodal fields. Conclusion Most patients treated in Z0011 received tangential RT alone, and some received no RT at all. Some patients received directed nodal irradiation via a third field. Further research is necessary to determine the optimal RT approach in patients with low-volume axillary disease treated with SLND alone. PMID:25135994

  9. Effect of Radiotherapy Dose and Volume on Relapse in Merkel Cell Cancer of the Skin

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Foote, Matthew, E-mail: matthew_foote@health.qld.gov.a; Harvey, Jennifer; Porceddu, Sandro

    Purpose: To assess the effect of radiotherapy (RT) dose and volume on relapse patterns in patients with Stage I-III Merkel cell carcinoma (MCC). Patients and Methods: This was a retrospective analysis of 112 patients diagnosed with MCC between January 2000 and December 2005 and treated with curative-intent RT. Results: Of the 112 evaluable patients, 88% had RT to the site of primary disease for gross (11%) or subclinical (78%) disease. Eighty-nine percent of patients had RT to the regional lymph nodes; in most cases (71%) this was for subclinical disease in the adjuvant or elective setting, whereas 21 patients (19%)more » were treated with RT to gross nodal disease. With a median follow-up of 3.7 years, the 2-year and 5-year overall survival rates were 72% and 53%, respectively, and the 2-year locoregional control rate was 75%. The in-field relapse rate was 3% for primary disease, and relapse was significantly lower for patients receiving {>=}50Gy (hazard ratio [HR] = 0.22; 95% confidence interval [CI], 0.06-0.86). Surgical margins did not affect the local relapse rate. The in-field relapse rate was 11% for RT to the nodes, with dose being significant for nodal gross disease (HR = 0.24; 95% CI, 0.07-0.87). Patients who did not receive elective nodal RT had a much higher rate of nodal relapse compared with those who did (HR = 6.03; 95% CI, 1.34-27.10). Conclusion: This study indicates a dose-response for subclinical and gross MCC. Doses of {>=}50Gy for subclinical disease and {>=}55Gy for gross disease should be considered. The draining nodal basin should be treated in all patients.« less

  10. Role of the EGF-Related Growth Factor cripto in Murine Mammary Tumorigenesis

    DTIC Science & Technology

    2000-10-01

    necessary for emergency repair or overhaul or (ii) is a release or disclosure of technical data (other than detailed manufacturing or process data) to, or...constructs that express secreted processed NODAL protein in transfected mammalian cells. We found that processing of unmodified NODAL protein is...NODAL processing (Constam and Robertson, 1999). As shown in our 1999 report, cleaved mature Nodal protein can be produced in the culture supernatants

  11. Nodal portraits of quantum billiards: Domains, lines, and statistics

    NASA Astrophysics Data System (ADS)

    Jain, Sudhir Ranjan; Samajdar, Rhine

    2017-10-01

    This is a comprehensive review of the nodal domains and lines of quantum billiards, emphasizing a quantitative comparison of theoretical findings to experiments. The nodal statistics are shown to distinguish not only between regular and chaotic classical dynamics but also between different geometric shapes of the billiard system itself. How a random superposition of plane waves can model chaotic eigenfunctions is discussed and the connections of the complex morphology of the nodal lines thereof to percolation theory and Schramm-Loewner evolution are highlighted. Various approaches to counting the nodal domains—using trace formulas, graph theory, and difference equations—are also illustrated with examples. The nodal patterns addressed pertain to waves on vibrating plates and membranes, acoustic and electromagnetic modes, wave functions of a "particle in a box" as well as to percolating clusters, and domains in ferromagnets, thus underlining the diversity and far-reaching implications of the problem.

  12. Topological Nodal-Net Semimetal in a Graphene Network Structure

    NASA Astrophysics Data System (ADS)

    Wang, Jian-Tao; Nie, Simin; Weng, Hongming; Kawazoe, Yoshiyuki; Chen, Changfeng

    2018-01-01

    Topological semimetals are characterized by the nodal points in their electronic structure near the Fermi level, either discrete or forming a continuous line or ring, which are responsible for exotic properties related to the topology of bulk bands. Here we identify by ab initio calculations a distinct topological semimetal that exhibits nodal nets comprising multiple interconnected nodal lines in bulk and have two coupled drumheadlike flat bands around the Fermi level on its surface. This nodal net semimetal state is proposed to be realized in a graphene network structure that can be constructed by inserting a benzene ring into each C- C bond in the bct-C4 lattice or by a crystalline modification of the (5,5) carbon nanotube. These results expand the realm of nodal manifolds in topological semimetals, offering a new platform for exploring novel physics in these fascinating materials.

  13. Low thrombospondin 2 expression is predictive of low tumor regression after neoadjuvant chemoradiotherapy in rectal cancer.

    PubMed

    Lin, Cheng-Yi; Lin, Ching-Yih; Chang, I-Wei; Sheu, Ming-Jen; Li, Chien-Feng; Lee, Sung-Wei; Lin, Li-Ching; Lee, Ying-En; He, Hong-Lin

    2015-01-01

    Neoadjuvant concurrent chemoradiotherapy (CCRT) followed by surgery is the mainstay of treatment for locally advanced rectal cancer. Several heparin-binding associated proteins have been reported to play a critical role in cancer progression. However, the clinical relevancies of such proteins and their associations with CCRT response in rectal cancer have not yet to be fully elucidated. The analysis of a public transcriptome of rectal cancer indicated that thrombospondin 2 (THBS2) is a predictive factor for CCRT response. Immunohistochemical analyses were conducted to evaluate the expression of THBS2 in pretreatment biopsy specimens from rectal cancer patients without distant metastasis. Furthermore, the relationships between THBS2 expression and various clinicopathological factors or survival were analyzed. Low expression of THBS2 was significantly associated with advanced pretreatment tumor (P<0.001) and nodal status (P=0.004), post-treatment tumor (P<0.001) and nodal status (P<0.001), increased vascular invasion (P=0.003), increased perineural invasion (P=0.023) and inferior tumor regression grade (P=0.015). In univariate analysis, low THBS2 expression predicted worse outcomes for disease-free survival, local recurrence-free survival and metastasis-free survival (all P<0.001). In multivariate analysis, low expression of THBS2 still served as a negative prognostic factor for disease-free survival (Hazard ratio=3.057, P=0.002) and metastasis-free survival (Hazard ratio=3.362, P=0.012). Low THBS2 expression was correlated with advanced disease status and low tumor regression after preoperative CCRT and that it acted as an independent negative prognostic factor in rectal cancer. THBS2 may represent a predictive biomarker for CCRT response in rectal cancer.

  14. Potential clinical value of PET/CT in predicting occult nodal metastasis in T1-T2N0M0 lung cancer patients staged by PET/CT

    PubMed Central

    Zhou, Xiang; Chen, Ruohua; Huang, Gang; Liu, Jianjun

    2017-01-01

    We assessed the clinical value of 2-fluoro-2-deoxyglucose (18F-FDG) PET/CT imaging for predicting occult nodal metastasis in non-small cell lung cancer (NSCLC) patients. This retrospective study included 54 patients with T1-2N0M0 NSCLC who had undergone 18F-FDG PET/CT before surgery. Occult nodal metastasis was detected in 25.9% (14/54) of the patients. Immunohistochemical analysis revealed that increased glucose transporter 1 expression was associated with occult nodal metastasis, but hexokinase 2 expression was not. Compared to the negative nodal metastasis group, the positive nodal metastasis group was associated with increased maximum standardized uptake value (SUVmax) and tumor size. Multivariate analysis indicated that SUVmax and tumor size were associated with nodal metastasis. Nodal metastasis could be predicted with a sensitivity of 92.9% and a specificity of 55.0% when the SUVmax cutoff was 4.35. When patients were divided into low-risk (tumor size ≤ 2.5 cm and SUVmax ≤ 4.35), moderate-risk (tumor size ≤ 2.5 cm and SUVmax > 4.35 or tumor size > 2.5 cm and SUVmax ≤ 4.35) and high-risk (tumor size > 2.5 cm and SUVmax > 4.35) groups, the lymph node metastasis rates were 4.3%, 22.7%, and 88.9%, respectively. These results indicate that the combination of SUVmax and tumor size has potential clinical value for predicting occult nodal metastasis in NSCLC patients. PMID:29137276

  15. Mechanism for generation of left isomerism in Ccdc40 mutant embryos

    PubMed Central

    Sugrue, Kelsey F.

    2017-01-01

    Leftward fluid flow in the mouse node is generated by cilia and is critical for initiating asymmetry of the left-right axis. Coiled-coil domain containing-40 (Ccdc40) plays an evolutionarily conserved role in the assembly of motile cilia and establishment of the left-right axis. Approximately one-third of Ccdc40lnks mutant embryos display situs defects and here we investigate the underlying mechanism. Ccdc40lnks mutants show delayed induction of markers of the left-lateral plate mesoderm (L-LPM) including Lefty1, Lefty2 and Nodal. Consistent with defective cilia motility compromising fluid flow across the node, initiation of asymmetric perinodal Cerberus like-2 (Cerl2) expression is delayed and then randomized. This is followed by delayed and then randomized asymmetric Nodal expression around the node. We propose a model to explain how left isomerism arises in a proportion of Ccdc40lnks mutants. We postulate that with defective motile cilia, Cerl2 expression remains symmetric and Nodal is antagonized equally on both sides of the node. This effectively reduces Nodal activation bilaterally, leading to reduced and delayed activation of Nodal and its antagonists in the LPM. This model is further supported by the failure to establish Nodal expression in the left-LPM with reduced Nodal gene dosage in Ccdc40lnks/lnks;NodalLacZ/+ mutants causing a predominance of right not left isomerism. Together these results suggest a model where cilia generated fluid flow in the node functions to ensure robust Nodal activation and a timely left-sided developmental program in the LPM. PMID:28182636

  16. Association Between Adjuvant Chemotherapy and Overall Survival in Patients With Rectal Cancer and Pathological Complete Response After Neoadjuvant Chemotherapy and Resection.

    PubMed

    Dossa, Fahima; Acuna, Sergio A; Rickles, Aaron S; Berho, Mariana; Wexner, Steven D; Quereshy, Fayez A; Baxter, Nancy N; Chadi, Sami A

    2018-04-19

    Although American guidelines recommend use of adjuvant chemotherapy in patients with locally advanced rectal cancer, individuals who achieve a pathological complete response (pCR) following neoadjuvant chemoradiotherapy are less likely to receive adjuvant treatment than incomplete responders. The association and resection of adjuvant chemotherapy with survival in patients with pCR is unclear. To determine whether patients with locally advanced rectal cancer who achieve pCR after neoadjuvant chemoradiation therapy and resection benefit from the administration of adjuvant chemotherapy. This retrospective propensity score-matched cohort study identified patients with locally advanced rectal cancer from the National Cancer Database from 2006 through 2012. We selected patients with nonmetastatic invasive rectal cancer who achieved pCR after neoadjuvant chemoradiation therapy and resection. We matched patients who received adjuvant chemotherapy to patients who did not receive adjuvant treatment in a 1:1 ratio. We separately matched subgroups of patients with node-positive disease before treatment and node-negative disease before treatment to investigate for effect modification by pretreatment nodal status. We compared overall survival between groups using Kaplan-Meier survival methods and Cox proportional hazards models. We identified 2455 patients (mean age, 59.5 years; 59.8% men) with rectal cancer with pCR after neoadjuvant chemoradiation therapy and resection. We matched 667 patients with pCR who received adjuvant chemotherapy and at least 8 weeks of follow-up after surgery to patients with pCR who did not receive adjuvant treatment. Over a median follow-up of 3.1 years (interquartile range, 1.94-4.40 years), patients treated with adjuvant chemotherapy demonstrated better overall survival than those who did not receive adjuvant treatment (hazard ratio, 0.44; 95% CI, 0.28-0.70). When stratified by pretreatment nodal status, only those patients with pretreatment node-positive disease exhibited improved overall survival with administration of adjuvant chemotherapy (hazard ratio, 0.24; 95% CI, 0.10-0.58). The administration of adjuvant chemotherapy in patients with rectal cancer with pCR is associated with improved overall survival, particularly in patients with pretreatment node-positive disease. Although this study suggests a beneficial effect of adjuvant treatment on survival in patients with pCR, these results are limited by the presence of potential unmeasured confounding in this nonrandomized study.

  17. Tumor response evaluation after neoadjuvant chemotherapy in locally advanced gastric adenocarcinoma: a prospective, multi-center cohort study

    PubMed Central

    De Martini, Paolo; Ceresoli, Marco; Mari, Giulio M.; Costanzi, Andrea; Maggioni, Dario; Pugliese, Raffaele; Ferrari, Giovanni

    2017-01-01

    Background To verify the prognostic value of the pathologic and radiological tumor response after neoadjuvant chemotherapy in the treatment of locally advanced gastric adenocarcinoma. Methods A total of 67 patients with locally advanced gastric cancer (clinical ≥ T2 or nodal disease and without evidence of distant metastases) underwent perioperative chemotherapy (ECF or ECX regimen) from December 2009 through June 2015 in two surgical units. Histopathological and radiological response to chemotherapy were evaluated by using tumor regression grade (TRG) (Becker’s criteria) and volume change assessed by CT. Results Fifty-one (86%) patients completed all chemotherapy scheduled cycles successfully and surgery was curative (R0) in 64 (97%) subjects. The histopathological analysis showed 19 (29%) specimens with TRG1 (less than 10% of vital tumor left) and 25 (37%) patients had partial or complete response (CR) assessed by CT scan. Median disease free survival (DFS) and overall survival (OS) were 25.70 months (range, 14.52–36.80 months) and 36.60 months (range, 24.3–52.9 months), respectively. The median follow up was 27 months (range, 5.00–68.00 months). Radiological response and TRG were found to be a prognostic factor for OS and DFS, while tumor histology was not significantly related to survival. Conclusions Both radiological response and TRG have been shown as promising survival markers in patients treated with perioperative chemotherapy for locally advanced gastric cancer. Other predictive markers of response to chemotherapy are strongly required. PMID:29299362

  18. The natural history of thin melanoma and the utility of sentinel lymph node biopsy.

    PubMed

    Durham, Alison B; Schwartz, Jennifer L; Lowe, Lori; Zhao, Lili; Johnson, Andrew G; Harms, Kelly L; Bichakjian, Christopher K; Orsini, Amy P; McLean, Scott A; Bradford, Carol R; Cohen, Mark S; Johnson, Timothy M; Sabel, Michael S; Wong, Sandra L

    2017-12-01

    Current literature may overestimate the risk of nodal metastasis from thin melanoma due to reporting of data only from lesions treated with SLNB. Our objective was to define the natural history of thin melanoma, assessing the likelihood of nodal disease, in order to guide selection for SLNB. Retrospective review. The primary outcome was the rate of nodal disease. Clinicopathologic factors were evaluated to find associations with nodal disease. Five hundred and twelve lesions, follow up available for 488 (median: 48 months). Lesions treated with WLE/SLNB compared to WLE alone were more likely to have high-risk features. The rate of nodal disease was higher in the WLE/SLNB group (24 positive SLNB, five false-negative SLNB with nodal recurrence: 10.2%) compared to WLE alone (four nodal recurrences: 2.0%). Univariate analysis showed age ≤45, Breslow depth ≥0.85 mm, mitotic rate >1 mm 2 , and ulceration were associated with nodal disease. Multivariate analysis confirmed the association of age ≤45 and ulceration. SLNB for melanoma 0.75-0.99 mm should be considered in patients age ≤45, Breslow depth ≥0.85 mm, mitotic rate >1 mm 2 , and/or with ulceration. Thin melanoma <0.85 mm without high-risk features may be treated with WLE alone. © 2017 Wiley Periodicals, Inc.

  19. A diagnosis model for early Tourette syndrome children based on brain structural network characteristics

    NASA Astrophysics Data System (ADS)

    Wen, Hongwei; Liu, Yue; Wang, Jieqiong; Zhang, Jishui; Peng, Yun; He, Huiguang

    2016-03-01

    Tourette syndrome (TS) is a childhood-onset neurobehavioral disorder characterized by the presence of multiple motor and vocal tics. Tic generation has been linked to disturbed networks of brain areas involved in planning, controlling and execution of action. The aim of our work is to select topological characteristics of structural network which were most efficient for estimating the classification models to identify early TS children. Here we employed the diffusion tensor imaging (DTI) and deterministic tractography to construct the structural networks of 44 TS children and 48 age and gender matched healthy children. We calculated four different connection matrices (fiber number, mean FA, averaged fiber length weighted and binary matrices) and then applied graph theoretical methods to extract the regional nodal characteristics of structural network. For each weighted or binary network, nodal degree, nodal efficiency and nodal betweenness were selected as features. Support Vector Machine Recursive Feature Extraction (SVM-RFE) algorithm was used to estimate the best feature subset for classification. The accuracy of 88.26% evaluated by a nested cross validation was achieved on combing best feature subset of each network characteristic. The identified discriminative brain nodes mostly located in the basal ganglia and frontal cortico-cortical networks involved in TS children which was associated with tic severity. Our study holds promise for early identification and predicting prognosis of TS children.

  20. Disrupted topological organization in whole-brain functional networks of heroin-dependent individuals: a resting-state FMRI study.

    PubMed

    Jiang, Guihua; Wen, Xue; Qiu, Yingwei; Zhang, Ruibin; Wang, Junjing; Li, Meng; Ma, Xiaofen; Tian, Junzhang; Huang, Ruiwang

    2013-01-01

    Neuroimaging studies have shown that heroin addiction is related to abnormalities in widespread local regions and in the functional connectivity of the brain. However, little is known about whether heroin addiction changes the topological organization of whole-brain functional networks. Seventeen heroin-dependent individuals (HDIs) and 15 age-, gender-matched normal controls (NCs) were enrolled, and the resting-state functional magnetic resonance images (RS-fMRI) were acquired from these subjects. We constructed the brain functional networks of HDIs and NCs, and compared the between-group differences in network topological properties using graph theory method. We found that the HDIs showed decreases in the normalized clustering coefficient and in small-worldness compared to the NCs. Furthermore, the HDIs exhibited significantly decreased nodal centralities primarily in regions of cognitive control network, including the bilateral middle cingulate gyrus, left middle frontal gyrus, and right precuneus, but significantly increased nodal centralities primarily in the left hippocampus. The between-group differences in nodal centralities were not corrected by multiple comparisons suggesting these should be considered as an exploratory analysis. Moreover, nodal centralities in the left hippocampus were positively correlated with the duration of heroin addiction. Overall, our results indicated that disruptions occur in the whole-brain functional networks of HDIs, findings which may be helpful in further understanding the mechanisms underlying heroin addiction.

  1. Plasticity in nodal root elongation through the hardpan triggered by rewatering during soil moisture fluctuation stress in rice.

    PubMed

    Suralta, Roel Rodriguez; Niones, Jonathan Manito; Kano-Nakata, Mana; Thi Tran, Thiem; Mitsuya, Shiro; Yamauchi, Akira

    2018-03-12

    Rainfed lowland (RFL) rice fields have hardpans and experience soil moisture fluctuations (SMF) stress, which influence root system development. Here, we clarify the expression and timing of the plasticity in nodal root elongation through the hardpan under SMF and its contribution to shoot growth using a shallow-rooting IR64 and its deep-rooting introgression line, YTH304. Under SMF, soil moisture content had negative relationship with soil penetration resistance, regardless of hardpan bulk densities. YTH304 had greater root system below the hardpan than IR64 in hardpan with 1.50 but not in 1.70 g cm -3 bulk density (BD). YTH304 had greater plasticity in nodal root elongation through the hardpan than IR64 under SMF, which was clearly expressed during rewatering. YTH304 also had greater soil water uptake below the hardpan during drought and greater shoot growth than IR64. The results imply that deep root system development during SMF was due to the plasticity in nodal root elongation through the hardpan expressed during rewatering rather than during drought periods. This is against the long standing belief that active root elongation through the hardpan happens during drought. This also implies a need to revisit current root screening methods to identify rice lines with good hardpan penetration ability.

  2. Method and apparatus for routing data in an inter-nodal communications lattice of a massively parallel computer system by employing bandwidth shells at areas of overutilization

    DOEpatents

    Archer, Charles Jens; Musselman, Roy Glenn; Peters, Amanda; Pinnow, Kurt Walter; Swartz, Brent Allen; Wallenfelt, Brian Paul

    2010-04-27

    A massively parallel computer system contains an inter-nodal communications network of node-to-node links. An automated routing strategy routes packets through one or more intermediate nodes of the network to reach a final destination. The default routing strategy is altered responsive to detection of overutilization of a particular path of one or more links, and at least some traffic is re-routed by distributing the traffic among multiple paths (which may include the default path). An alternative path may require a greater number of link traversals to reach the destination node.

  3. The Effect of Anatomical Location of Lymph Node Metastases on Cancer Specific Survival in Patients with Clear Cell Renal Cell Carcinoma.

    PubMed

    Nini, Alessandro; Larcher, Alessandro; Cianflone, Francesco; Trevisani, Francesco; Terrone, Carlo; Volpe, Alessandro; Regis, Federica; Briganti, Alberto; Salonia, Andrea; Montorsi, Francesco; Bertini, Roberto; Capitanio, Umberto

    2018-01-01

    Positive nodal status (pN1) is an independent predictor of survival in renal cell carcinoma (RCC) patients. However, no study to date has tested whether the location of lymph node (LN) metastases does affect oncologic outcomes in a population submitted to radical nephrectomy (RN) and extended lymph node dissection (eLND). To describe nodal disease dissemination in clear cell RCC (ccRCC) patients and to assess the effect of the anatomical sites and the number of nodal areas affected on cancer specific mortality (CSM). The study included 415 patients who underwent RN and eLND, defined as the removal of hilar, side-specific (pre/paraaortic or pre/paracaval) and interaortocaval LNs for ccRCC, at two institutions. Descriptive statistics were used to depict nodal dissemination in pN1 patients, stratified according to nodal site and number of involved areas. Multivariable Cox regression analyses and Kaplan-Meier curves were used to explore the relationship between pN1 disease features and survival outcomes. Median number of removed LN was 14 (IQR 9-19); 23% of patients were pN1. Among patients with one involved nodal site, 54 and 26% of patients were positive only in side-specific and interaortocaval station, respectively. The most frequent nodal site was the interaortocaval and side-specific one, for right and left ccRCC, respectively. Interaortocaval nodal positivity (HR 2.3, CI 95%: 1.3-3.9, p < 0.01) represented an independent predictor of CSM. When ccRCC patient harbour nodal disease, its spreading can occur at any nodal station without involving the others. The presence of interoartocaval positive nodes does affect oncologic outcomes. Lymph node invasion in patients with clear cell renal cell carcinoma is not following a fixed anatomical pattern. An extended lymph node dissection, during treatment for primary kidney tumour, would aid patient risk stratification and multimodality upfront treatment.

  4. Optical conductivity of three and two dimensional topological nodal-line semimetals

    NASA Astrophysics Data System (ADS)

    Barati, Shahin; Abedinpour, Saeed H.

    2017-10-01

    The peculiar shape of the Fermi surface of topological nodal-line semimetals at low carrier concentrations results in their unusual optical and transport properties. We analytically investigate the linear optical responses of three- and two-dimensional nodal-line semimetals using the Kubo formula. The optical conductivity of a three-dimensional nodal-line semimetal is anisotropic. Along the axial direction (i.e., the direction perpendicular to the nodal-ring plane), the Drude weight has a linear dependence on the chemical potential at both low and high carrier dopings. For the radial direction (i.e., the direction parallel to the nodal-ring plane), this dependence changes from linear into quadratic in the transition from low into high carrier concentration. The interband contribution into optical conductivity is also anisotropic. In particular, at large frequencies, it saturates to a constant value for the axial direction and linearly increases with frequency along the radial direction. In two-dimensional nodal-line semimetals, no interband optical transition could be induced and the only contribution to the optical conductivity arises from the intraband excitations. The corresponding Drude weight is independent of the carrier density at low carrier concentrations and linearly increases with chemical potential at high carrier doping.

  5. Cilia are required for asymmetric nodal induction in the sea urchin embryo.

    PubMed

    Tisler, Matthias; Wetzel, Franziska; Mantino, Sabrina; Kremnyov, Stanislav; Thumberger, Thomas; Schweickert, Axel; Blum, Martin; Vick, Philipp

    2016-08-23

    Left-right (LR) organ asymmetries are a common feature of metazoan animals. In many cases, laterality is established by a conserved asymmetric Nodal signaling cascade during embryogenesis. In most vertebrates, asymmetric nodal induction results from a cilia-driven leftward fluid flow at the left-right organizer (LRO), a ciliated epithelium present during gastrula/neurula stages. Conservation of LRO and flow beyond the vertebrates has not been reported yet. Here we study sea urchin embryos, which use nodal to establish larval LR asymmetry as well. Cilia were found in the archenteron of embryos undergoing gastrulation. Expression of foxj1 and dnah9 suggested that archenteron cilia were motile. Cilia were polarized to the posterior pole of cells, a prerequisite of directed flow. High-speed videography revealed rotating cilia in the archenteron slightly before asymmetric nodal induction. Removal of cilia through brief high salt treatments resulted in aberrant patterns of nodal expression. Our data demonstrate that cilia - like in vertebrates - are required for asymmetric nodal induction in sea urchin embryos. Based on these results we argue that the anterior archenteron represents a bona fide LRO and propose that cilia-based symmetry breakage is a synapomorphy of the deuterostomes.

  6. Nodal Topological Phases in s-wave Superfluid of Ultracold Fermionic Gases

    NASA Astrophysics Data System (ADS)

    Huang, Bei-Bing; Yang, Xiao-Sen

    2018-02-01

    The gapless Weyl superfluid has been widely studied in the three-dimensional ultracold fermionic superfluid. In contrast to Weyl superfluid, there exists another kind of gapless superfluid with topologically protected nodal lines, which can be regarded as the superfluid counterpart of nodal line semimetal in the condensed matter physics, just as Weyl superfluid with Weyl semimetal. In this paper we study the ground states of the cold fermionic gases in cubic optical lattices with one-dimensional spin-orbit coupling and transverse Zeeman field and map out the topological phase diagram of the system. We demonstrate that in addition to a fully gapped topologically trivial phase, some different nodal line superfluid phases appear when the Zeeman field is adjusted. The presence of topologically stable nodal lines implies the dispersionless zero-energy flat band in a finite region of the surface Brillouin zone. Experimentally these nodal line superfluid states can be detected via the momentum-resolved radio-frequency spectroscopy. The nodal line topological superfluid provide fertile grounds for exploring exotic quantum matters in the context of ultracold atoms. Supported by National Natural Science Foundation of China under Grant Nos. 11547047 and 11504143

  7. Retrospective Analysis of Outcome Differences in Preoperative Concurrent Chemoradiation With or Without Elective Nodal Irradiation for Esophageal Squamous Cell Carcinoma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hsu, Feng-Ming; Cancer Research Center, National Taiwan University College of Medicine, Taipei, Taiwan; Graduate Institute of Biomedical Electronics and Bioinformatics, National Taiwan University, Taipei, Taiwan

    2011-11-15

    Purpose: To evaluate the efficacy and patterns of failure of elective nodal irradiation (ENI) in patients with esophageal squamous cell carcinoma (SCC) undergoing preoperative concurrent chemoradiation (CCRT) followed by radical surgery. Methods and Materials: We retrospectively studied 118 patients with AJCC Stage II to III esophageal SCC undergoing preoperative CCRT (median, 36 Gy), followed by radical esophagectomy. Of them, 73 patients (62%) had ENI and 45 patients (38%) had no ENI. Patients with ENI received radiotherapy to either supraclavicular (n = 54) or celiac (n = 19) lymphatics. Fifty-six patients (57%) received chemotherapy with paclitaxel plus cisplatin. The 3-year progression-freemore » survival, overall survival, and patterns of failure were analyzed. Distant nodal recurrence was classified into M1a and M1b regions. A separate analysis using matched cases was conducted. Results: The median follow-up was 38 months. There were no differences in pathological complete response rate (p = 0.12), perioperative mortality rate (p = 0.48), or delayed Grade 3 or greater cardiopulmonary toxicities (p = 0.44), between the groups. More patients in the non-ENI group had M1a failure than in the ENI group, with 3-year rates of 11% and 3%, respectively (p = 0.05). However, the 3-year isolated distant nodal (M1a + M1b) failure rates were not different (ENI, 10%; non-ENI, 14%; p = 0.29). In multivariate analysis, pathological nodal status was the only independent prognostic factor associated with overall survival (hazard ratio = 1.78, p = 0.045). The 3-year overall survival and progression-free survival were 45% and 45%, respectively, in the ENI group, and 52% and 43%, respectively, in the non-ENI group (p = 0.31 and 0.89, respectively). Matched cases analysis did not show a statistical difference in outcomes between the groups. Conclusions: ENI reduced the M1a failure rate but was not associated with improved outcomes in patients undergoing preoperative CCRT for esophageal SCC. Pathological nodal metastasis predicted poor outcome.« less

  8. Pediatric and adolescent lymphoma: comparison of whole-body STIR half-Fourier RARE MR imaging with an enhanced PET/CT reference for initial staging.

    PubMed

    Punwani, Shonit; Taylor, Stuart A; Bainbridge, Alan; Prakash, Vineet; Bandula, Steven; De Vita, Enrico; Olsen, Oystein E; Hain, Sharon F; Stevens, Nicola; Daw, Stephen; Shankar, Ananth; Bomanji, Jamshed B; Humphries, Paul D

    2010-04-01

    To compare the diagnostic performance of rapid whole-body anatomic magnetic resonance (MR) staging of pediatric and adolescent lymphoma to an enhanced positron emission tomographic (PET)/computed tomographic (CT) reference standard. Ethical permission was given by the University College London Hospital ethics committee, and informed written consent was obtained from all participants and/or parents or guardians. Thirty-one subjects (age range, 7.3-18.0 years; 18 male, 11 female) with histologically proved lymphoma were prospectively recruited. Pretreatment staging was performed with whole-body short inversion time inversion-recovery (STIR) half-Fourier rapid acquisition with relaxation enhancement (RARE) MR imaging, fluorine 18 fluorodeoxyglucose PET/CT, and contrast agent-enhanced chest CT. Twenty-six subjects had posttreatment PET/CT and compromised our final cohort. Eleven nodal and 11 extranodal sites per patient were assessed on MR imaging by two radiologists in consensus, with a nodal short-axis threshold of >1 cm and predefined extranodal positivity criteria. The same sites were independantly evaluated by two nuclear medicine physicians on PET/CT images. Disease positivity was defined as a maximum standardized uptake value >2.5 or nodal size >1 cm. An unblinded expert panel reevaluated the imaging findings, removing perceptual errors, and derived an enhanced PET/CT reference standard (taking into account chest CT and 3-month follow-up imaging) against which the reported and intrinsic performance of MR imaging was assessed by using the kappa statistic. There was very good agreement between MR imaging and the enhanced PET/CT reference standard for nodal and extranodal staging (kappa = 0.96 and 0.86, respectively) which improved following elimination of perceptual errors (kappa = 0.97 and 0.91, respectively). The sensitivity and specificity of MR imaging (following removal of perceptual error) were 98% and 99%, respectively, for nodal disease and 91% and 99%, respectively, for extranodal disease. Whole-body STIR half-Fourier RARE MR imaging of pediatric and adolescent lymphoma can accurately depict nodal and extranodal disease and may provide an alternative nonionizing imaging method for anatomic disease assessment at initial staging. RSNA, 2010

  9. SU-E-T-157: Evaluation and Comparison of Doses to Pelvic Lymph Nodes and to Point B with 3D Image Guided Treatment Planning for High Dose Brachytherapy for Treatment of Cervical Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bhandare, N.

    2014-06-01

    Purpose: To estimate and compare the doses received by the obturator, external and internal iliac lymph nodes and point Methods: CT-MR fused image sets of 15 patients obtained for each of 5 fractions of HDR brachytherapy using tandem and ring applicator, were used to generate treatment plans optimized to deliver a prescription dose to HRCTV-D90 and to minimize the doses to organs at risk (OARs). For each set of image, target volume (GTV, HRCTV) OARs (Bladder, Rectum, Sigmoid), and both left and right pelvic lymph nodes (obturator, external and internal iliac lymph nodes) were delineated. Dose-volume histograms (DVH) were generatedmore » for pelvic nodal groups (left and right obturator group, internal and external iliac chains) Per fraction DVH parameters used for dose comparison included dose to 100% volume (D100), and dose received by 2cc (D2cc), 1cc (D1cc) and 0.1 cc (D0.1cc) of nodal volume. Dose to point B was compared with each DVH parameter using 2 sided t-test. Pearson correlation were determined to examine relationship of point B dose with nodal DVH parameters. Results: FIGO clinical stage varied from 1B1 to IIIB. The median pretreatment tumor diameter measured on MRI was 4.5 cm (2.7– 6.4cm).The median dose to bilateral point B was 1.20 Gy ± 0.12 or 20% of the prescription dose. The correlation coefficients were all <0.60 for all nodal DVH parameters indicating low degree of correlation. Only 2 cc of obturator nodes was not significantly different from point B dose on t-test. Conclusion: Dose to point B does not adequately represent the dose to any specific pelvic nodal group. When using image guided 3D dose-volume optimized treatment nodal groups should be individually identified and delineated to obtain the doses received by pelvic nodes.« less

  10. SU-F-P-52: A Meta-Analysis of Controlled Clinical Trials Comparing Elective Nodal Irradiation with Involved-Field Irradiation for Conformal Or Intensity-Modulated Radiotherapy in Patients with Esophageal Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bai, W; Zhang, R; Zhou, Z

    Purpose: To compare elective nodal irradiation with involved-field irradiation for three-dimensional conformal radiotherapy or intensity-modulated radiotherapy in patients with esophageal cancer by a metaanalysis. Methods: Wanfang, CNKI, VIP, CBM databases, PubMed, Embase and Cochrane Library were searched to identify the controlled clinical trials of elective nodal irradiation with involved-field irradiation for three-dimensional conformal radiotherapy or intensity-modulated radiotherapy in patients with esophageal cancer. The obtained data were analyzed using Stata 11.0. The difference between two groups was estimated by calculating the odds ratio (OR) with 95% confidence interval (95% CI). Results: A total of 12 controlled clinical trials involving 1095 esophagealmore » cancer patients, which were selected according to inclusion and exclusion criteria, were included in this meta-analysis. The meta-analysis showed that the elective nodal irradiation group reduced the rates of out-field failure comparing with involved-field irradiation group (OR=3.727, P=0.007). However, the rates of ≥grades 3 acute radiation pneumonitis and esophagitis were significantly higher in the elective nodal irradiation group than in the involved-field irradiation group (OR=0.348, P=0.001, OR=0.385, P=0.000). 1-, 2-, 3-year local control rates (OR=0.966, P=0.837, OR=0.946, P=0.781; OR=0.732P=0.098) and 1-, 3-, 5-year survival rates were similar in the two groups ( OR=0.966, P=0.837; OR=0.946, P=0.781; OR=0.732, P=0.098; OR=0.952, P=0.756; OR=1.149, P=0.422; OR=0.768, P=0.120). It is the same with the rates of distant metastasis (OR=0.986, P=0.937). Conclusion: Compared with involved-field irradiation, the elective nodal irradiation can reduce the rates of out-field failure for three-dimensional conformal radiotherapy or intensity-modulated radiotherapy in patients with esophageal cancer. However, its advantage of local control and survival rates is not obvious and it increases the incidence of toxicities.« less

  11. Differential role of Sloan–Kettering Institute (Ski) protein in Nodal and transforming growth factor-beta (TGF-β)-induced Smad signaling in prostate cancer cells

    PubMed Central

    Khan, Shafiq A.

    2012-01-01

    Transforming growth factor-beta (TGF-β) signaling pathways contain both tumor suppressor and tumor promoting activities. We have demonstrated that Nodal, another member of the TGF-β superfamily, and its receptors are expressed in prostate cancer cells. Nodal and TGF-β exerted similar biological effects on prostate cells; both inhibited proliferation in WPE, RWPE1 and DU145 cells, whereas neither had any effect on the proliferation of LNCaP or PC3 cells. Interestingly, Nodal and TGF-β induced migration in PC3 cells, but not in DU145 cells. TGF-β induced predominantly phosphorylation of Smad3, whereas Nodal induced phosphorylation of only Smad2. We also determined the expression and differential role of Ski, a corepressor of Smad2/3, in Nodal and TGF-β signaling in prostate cancer cells. Similar levels of Ski mRNA were found in several established prostate cell lines; however, high levels of Ski protein were only detected in prostate cancer cells and prostate cancer tissue samples. Exogenous Nodal and TGF-β had no effects on Ski mRNA levels. On the other hand, TGF-β induced a rapid degradation of Ski protein mediated by the proteasomal pathway, whereas Nodal had no effect on Ski protein. Reduced Ski levels correlated with increased basal and TGF-β-induced Smad2/3 phosphorylation. Knockdown of endogenous Ski reduced proliferation in DU145 cells and enhanced migration of PC3 cells. We conclude that high levels of Ski expression in prostate cancer cells may be responsible for repression of TGF-β and Smad3 signaling, but Ski protein levels do not influence Nodal and Smad2 signaling. PMID:22843506

  12. Long-term results of high-dose conformal radiotherapy for patients with medically inoperable T1-3N0 non-small-cell lung cancer: is low incidence of regional failure due to incidental nodal irradiation?

    PubMed

    Chen, Ming; Hayman, James A; Ten Haken, Randall K; Tatro, Daniel; Fernando, Shaneli; Kong, Feng-Ming

    2006-01-01

    To report the results of high-dose conformal irradiation and examine incidental nodal irradiation and nodal failure in patients with inoperable early-stage non-small-cell lung cancer (NSCLC). This analysis included patients with inoperable CT-staged T1-3N0M0 NSCLC treated on our prospective dose-escalation trial. Patients were treated with radiation alone (total dose, 63-102.9 Gy in 2.1-Gy daily fractions) with a three-dimensional conformal technique without intentional nodal irradiation. Bilateral highest mediastinal and upper/lower paratracheal, prevascular and retrotracheal, sub- and para-aortic, subcarinal, paraesophageal, and ipsilateral hilar regions were delineated individually. Nodal failure and doses of incidental irradiation were studied. The potential median follow-up was 104 months. For patients who completed protocol treatment, median survival was 31 months. The actuarial overall survival rate was 86%, 61%, 43%, and 21% and the cause-specific survival rate was 89%, 70%, 53%, and 35% at 1, 2, 3, and 5 years, respectively. Weight loss (p = 0.008) and radiation dose in Gy (p = 0.013) were significantly associated with overall survival. In only 22% and 13% of patients examined did ipsilateral hilar and paratracheal (and subaortic for left-sided tumor) nodal regions receive a dose of > or = 40 Gy, respectively. Less than 10% of all other nodal regions received a dose of > or = 40 Gy. No patients failed initially at nodal sites. Radiation dose is positively associated with overall survival in patients with medically inoperable T1-3N0 NSCLC, though long-term results remain poor. The nodal failure rate is low and does not seem to be due to high-dose incidental irradiation.

  13. Implications of Pathologic Complete Response Beyond Mediastinal Nodal Clearance With High-Dose Neoadjuvant Chemoradiation Therapy in Locally Advanced, Non-Small Cell Lung Cancer.

    PubMed

    Vyfhuis, Melissa A L; Burrows, Whitney M; Bhooshan, Neha; Suntharalingam, Mohan; Donahue, James M; Feliciano, Josephine; Badiyan, Shahed; Nichols, Elizabeth M; Edelman, Martin J; Carr, Shamus R; Friedberg, Joseph; Henry, Gavin; Stewart, Shelby; Sachdeva, Ashutosh; Pickering, Edward M; Simone, Charles B; Feigenberg, Steven J; Mohindra, Pranshu

    2018-06-01

    To determine, in a retrospective analysis of a large cohort of stage III non-small cell lung cancer patients treated with curative intent at our institution, whether having a pathologic complete response (pCR) influenced overall survival (OS) or freedom from recurrence (FFR) in patients who underwent definitive (≥60 Gy) neoadjuvant doses of chemoradiation (CRT). At our institution, 355 patients with locally advanced non-small cell lung cancer were treated with curative intent with definitive CRT (January 2000-December 2013), of whom 111 underwent mediastinal reassessment for possible surgical resection. Ultimately 88 patients received trimodality therapy. Chi-squared analysis was used to compare categorical variables. The Kaplan-Meier analysis was performed to estimate OS and FFR, with Cox regression used to determine the absolute hazards. Using high-dose neoadjuvant CRT, we observed a mediastinal nodal clearance (MNC) rate of 74% (82 of 111 patients) and pCR rate of 48% (37 of 77 patients). With a median follow-up of 34.2 months (range, 3-177 months), MNC resulted in improved OS and FFR on both univariate (OS: hazard ratio [HR] 0.455, 95% confidence interval [CI] 0.272-0.763, P = .004; FFR: HR 0.426, 95% CI 0.250-0.726, P = .002) and multivariate analysis (OS: HR 0.460, 95% CI 0.239-0.699, P = .001; FFR: HR 0.455, 95% CI 0.266-0.778, P = .004). However, pCR did not independently impact OS (P = .918) or FFR (P = .474). Mediastinal nodal clearance after CRT continues to be predictive of improved survival for patients undergoing trimodality therapy. However, a pCR at both the primary and mediastinum did not further improve survival outcomes. Future therapies should focus on improving MNC to encourage more frequent use of surgery and might justify use of preoperative CRT over chemotherapy alone. Copyright © 2018 Elsevier Inc. All rights reserved.

  14. Quantum oscillations in nodal line systems

    NASA Astrophysics Data System (ADS)

    Yang, Hui; Moessner, Roderich; Lim, Lih-King

    2018-04-01

    We study signatures of magnetic quantum oscillations in three-dimensional nodal line semimetals at zero temperature. The extended nature of the degenerate bands can result in a Fermi surface geometry with topological genus one, as well as a Fermi surface of electron and hole pockets encapsulating the nodal line. Moreover, the underlying two-band model to describe a nodal line is not unique, in that there are two classes of Hamiltonian with distinct band topology giving rise to the same Fermi-surface geometry. After identifying the extremal cyclotron orbits in various magnetic field directions, we study their concomitant Landau levels and resulting quantum oscillation signatures. By Landau-fan-diagram analyses, we extract the nontrivial π Berry phase signature for extremal orbits linking the nodal line.

  15. Nodes of Ranvier Act as Barriers to Restrict Invasion of Flanking Paranodal Domains in Myelinated Axons

    PubMed Central

    Thaxton, Courtney; Pillai, Anilkumar M.; Pribisko, Alaine L.; Dupree, Jeffrey L.; Bhat, Manzoor A.

    2010-01-01

    Accumulation of voltage gated sodium (Nav) channels at nodes of Ranvier is paramount for action potential propagation along myelinated fibers, yet the mechanisms governing nodal development, organization and stabilization remain unresolved. Here, we report that genetic ablation of the neuron-specific isoform of Neurofascin (NfascNF186) in vivo results in nodal disorganization, including loss of Nav channel and ankyrin-G (AnkG) enrichment at nodes in the peripheral (PNS) and central (CNS) nervous systems. Interestingly, the presence of paranodal domains failed to rescue nodal organization in the PNS and the CNS. Most importantly, using ultrastructural analysis, we demonstrate that the paranodal domains invade the nodal space in NfascNF186 mutant axons and occlude node formation. Our results suggest that NfascNF186-dependent assembly of the nodal complex acts as a molecular boundary to restrict the movement of flanking paranodal domains into the nodal area, thereby facilitating the stereotypic axonal domain organization and saltatory conduction along myelinated axons. PMID:21262464

  16. A quantitative description of normal AV nodal conduction curve in man.

    PubMed

    Teague, S; Collins, S; Wu, D; Denes, P; Rosen, K; Arzbaecher, R

    1976-01-01

    The AV nodal conduction curve generated by the atrial extrastimulus technique has been described only qualitatively in man, making clinical comparison of known normal curves with those of suspected AV nodal dysfunction difficult. Also, the effects of physiological and pharmacological interventions have not been quantifiable. In 50 patients with normal AV conduction as defined by normal AH (less than 130 ms), normal AV nodal effective and functional refractory periods (less than 380 and less than 500 ms), and absence of demonstrable dual AV nodal pathways, we found that conduction curves (at sinus rhythm or longest paced cycle length) can be described by an exponential equation of the form delta = Ae-Bx. In this equation, delta is the increase in AV nodal conduction time of an extrastimulus compared to that of a regular beat and x is extrastimulus interval. The natural logarithm of this equation is linear in the semilogarithmic plane, thus permitting the constants A and B to be easily determined by a least-squares regression analysis with a hand calculator.

  17. Topological nodal-line fermions in spin-orbit metal PbTaSe2

    PubMed Central

    Bian, Guang; Chang, Tay-Rong; Sankar, Raman; Xu, Su-Yang; Zheng, Hao; Neupert, Titus; Chiu, Ching-Kai; Huang, Shin-Ming; Chang, Guoqing; Belopolski, Ilya; Sanchez, Daniel S.; Neupane, Madhab; Alidoust, Nasser; Liu, Chang; Wang, BaoKai; Lee, Chi-Cheng; Jeng, Horng-Tay; Zhang, Chenglong; Yuan, Zhujun; Jia, Shuang; Bansil, Arun; Chou, Fangcheng; Lin, Hsin; Hasan, M. Zahid

    2016-01-01

    Topological semimetals can support one-dimensional Fermi lines or zero-dimensional Weyl points in momentum space, where the valence and conduction bands touch. While the degeneracy points in Weyl semimetals are robust against any perturbation that preserves translational symmetry, nodal lines require protection by additional crystalline symmetries such as mirror reflection. Here we report, based on a systematic theoretical study and a detailed experimental characterization, the existence of topological nodal-line states in the non-centrosymmetric compound PbTaSe2 with strong spin-orbit coupling. Remarkably, the spin-orbit nodal lines in PbTaSe2 are not only protected by the reflection symmetry but also characterized by an integer topological invariant. Our detailed angle-resolved photoemission measurements, first-principles simulations and theoretical topological analysis illustrate the physical mechanism underlying the formation of the topological nodal-line states and associated surface states for the first time, thus paving the way towards exploring the exotic properties of the topological nodal-line fermions in condensed matter systems. PMID:26829889

  18. Layer-oriented total pelvic exenteration for locally advanced primary colorectal cancer.

    PubMed

    Koda, Keiji; Shuto, Kiyohiko; Matsuo, Kenichi; Kosugi, Chihiro; Mori, Mikito; Hirano, Atsushi; Hiroshima, Yukihiko; Tanaka, Kuniya

    2016-01-01

    The clinical outcomes of patients who have undergone total pelvic exenteration (TPE) for locally advanced primary colorectal cancer have not been satisfactory. For the last 13 years, we have performed layer-oriented, en bloc resection of tumor for which TPE is indicated, in the hope of improving postoperative outcomes. The clinical outcomes of these cases were retrospectively analyzed. A total of 54 patients who underwent TPE from 1986 to 2013 were retrospectively analyzed. Since 2002, a layer-oriented removal for clinical T4 colorectal cancer, as in T3 or less invasive tumors removed by total mesorectal excision, was applied to 23 cases for which TPE was indicated. Postoperative mortality, morbidity, overall survival (OS), and disease-free survival (DFS) were evaluated. On univariate analysis, good postoperative OS and DFS were associated with the layer-oriented operative maneuver, blood loss less than 2000 mL, negative nodal metastasis, and no preoperative radiation therapy. Male sex was the marginal determinant correlated with good OS and DFS. Depth of invasion to T3 was the marginal determinant correlated with good DFS. On multivariate analysis using the 4 factors identified on univariate analyses, the layer-oriented operative procedure was a significant determinant for both good OS and DFS, together with negative nodal metastases. Postoperative mortality and morbidity in the layer-oriented excision were acceptable. For primary colorectal cancers for which TPE is indicated, layer-oriented excision was a safe and effective procedure, and it may be recommended as one of the standard surgical approaches in TPE.

  19. The application of the mesh-free method in the numerical simulations of the higher-order continuum structures

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sun, Yuzhou, E-mail: yuzhousun@126.com; Chen, Gensheng; Li, Dongxia

    2016-06-08

    This paper attempts to study the application of mesh-free method in the numerical simulations of the higher-order continuum structures. A high-order bending beam considers the effect of the third-order derivative of deflections, and can be viewed as a one-dimensional higher-order continuum structure. The moving least-squares method is used to construct the shape function with the high-order continuum property, the curvature and the third-order derivative of deflections are directly interpolated with nodal variables and the second- and third-order derivative of the shape function, and the mesh-free computational scheme is establish for beams. The coupled stress theory is introduced to describe themore » special constitutive response of the layered rock mass in which the bending effect of thin layer is considered. The strain and the curvature are directly interpolated with the nodal variables, and the mesh-free method is established for the layered rock mass. The good computational efficiency is achieved based on the developed mesh-free method, and some key issues are discussed.« less

  20. Oligorecurrent prostate cancer limited to lymph nodes: getting our ducks in a row

    PubMed

    Fodor, Andrei; Lancia, Andrea; Ceci, Francesco; Picchio, Maria; Hoyer, Morten; Jereczek-Fossa, Barbara Alicja; Ost, Piet; Castellucci, Paolo; Incerti, Elena; Di Muzio, Nadia; Ingrosso, Gianluca

    2018-05-11

    Oligorecurrent prostate cancer with exclusive nodal involvement represents a common state of disease, amenable to local therapy. New radio-labeled tracers have enriched the possibility of cancer detection and treatment. In this review, we aim to illustrate the main nuclear medicine diagnostic options and the role of radiotherapy in this setting of patients. We performed a PubMed search referring to the PRISMA guidelines to analyze the performance of PSMA- and choline-PET in detecting oligorecurrence limited to lymph nodes, and to review the main studies supporting either ablative stereotactic body radiotherapy or regional lymph node irradiation in this clinical setting. PSMA-PET has shown higher efficacy in the diagnosis of nodal lesions if compared with choline-PET. More specifically, for PSA ≤ 2 ng/ml, the median detection rate of choline-PET ranges from 19.5 to 44.5%, whereas PSMA ranges from 51.5 to 74%. SBRT achieves high local control rates positively affecting progression-free survival (PFS), with androgen deprivation therapy (ADT)-free survival ranging from 25 to 44 months and with low toxicity rates (0-15%). Prophylactic nodal irradiation shows 3-year PFS rates ranging from 62 to 75%, but with a potential higher risk of toxicity. However, the chosen treatment option needs to be tailored on the single patient. Newer PET/CT radio-labeled tracers have increased disease detection in oligorecurrent prostate cancer patients. Growing evidence of their impact on metastasis-directed therapy encourages the use of the most advanced radiotherapy techniques in the clinical management of such patients.

  1. Clinical and anatomical guidelines in pelvic cancer contouring for radiotherapy treatment planning.

    PubMed

    Portaluri, Maurizio; Bambace, Santa; Perez, Celeste; Giuliano, Giuseppe; Angone, Grazia; Scialpi, Michele; Pili, Giorgio; Didonna, Vittorio; Alloro, Emira

    2004-08-01

    Many observations on potential inadequate coverage of tumour volume at risk in advanced cervical cancer (CC) when conventional radiation fields are used, have further substantiated by investigators using MRI, CT or lymphangiographic imaging. This work tries to obtain three dimensional margins by observing enlarged nodes in CT scans in order to improve pelvic nodal chains clinical target volumes (CTVs) drawing, and by looking for corroborative evidence in the literature for a better delineation of tumour CTV. Eleven consecutive patients (seven males, four females, mean age 62 years, range 43-78) with CT diagnosis of nodal involvement caused by pathologically proved carcinoma of the cervix (n = 2), carcinoma of the rectum (n = 2), carcinoma of the prostate (n = 2), non-Hodgkin lymphoma (n = 2), Hodgkin lymphoma (n = 1), carcinoma of the penis (n = 1) and carcinoma of the corpus uteri (n = 1) were retrospectively reviewed. Sixty CT scans with 67 enlarged pelvic nodes were reviewed in order to record the more proximal structures (muscle, bone, vessels, cutis or subcutis and other organs) to each enlarged node or group of nodes according to the four surfaces (anterior, lateral, posterior and medial) in a clockwise direction. A summary of the observations of each nodal chain and the number of occurrences of every marginal structure on axial CT slices is presented. Finally, simple guidelines are proposed. Tumour CTV should be based on individual tumour anatomy-mainly for lateral beams as it results from sagittal T2 weighted MRI images. Boundaries of pelvic nodes CTVs can be derived from observations of enlarged lymph nodes in CT scans.

  2. Cell boundary fault detection system

    DOEpatents

    Archer, Charles Jens [Rochester, MN; Pinnow, Kurt Walter [Rochester, MN; Ratterman, Joseph D [Rochester, MN; Smith, Brian Edward [Rochester, MN

    2009-05-05

    A method determines a nodal fault along the boundary, or face, of a computing cell. Nodes on adjacent cell boundaries communicate with each other, and the communications are analyzed to determine if a node or connection is faulty.

  3. Occult nodal metastasis in solid carcinomata

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Moloy, P.J.; Nicolson, G.L.

    1987-01-01

    This book contains 23 selections. Some of the titles are: Rationale for radiotherapy in subclinical nodal disease; rationale of chemotherapy for nodal disease: The stabilization of topoisomerase II-DNA complexes as a mechanism of antineoplastic drug action; magnetic resonance imaging of malignant cervical adenopathy; and local and regional immune function in cancer patients.

  4. Localization of malignant melanoma using monoclonal antibodies

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wasselle, J.; Becker, J.; Cruse, W.

    1991-04-01

    Finding a screening test to evaluate patients with cancer for occult metastatic disease, as well as imaging all known disease, is a goal of research efforts. Twenty-nine evaluable patients with deeply invasive (stage I), regional nodal (stage II), or systemic (stage III) melanoma underwent imaging by administration of a preparation of the antimelanoma antibody labeled with technetium 99m. Scan results indicated that 28 of 32 confirmed metastatic sites were imaged with this technique (88% sensitivity). Analysis of the individual positive sites revealed that nodal basins and visceral metastases accounted for the highest percentage of metastatic sites imaged, with 14 (88%)more » of 16 nodal basin metastases and all four visceral metastases being detected through imaging. Occult nodal disease was detected in the iliac nodal chain in two of the 29 patients. The imaging of benign tumors and nodal basins not containing disease accounted for a confirmed false-positive rate of 21%. Three (10%) of the 29 scan results were confirmed to be false-negative. In vivo tumor localization with monoclonal antibodies showed a sensitivity similar to that of other roentgenographic procedures for identifying metastatic disease and was useful in two of three patients in identifying occult iliac nodal disease, a region that is difficult to evaluate with physical examination and other imaging modalities.« less

  5. Nodal enhances the activity of FoxO3a and its synergistic interaction with Smads to regulate cyclin G2 transcription in ovarian cancer cells.

    PubMed

    Fu, G; Peng, C

    2011-09-15

    Nodal, a member of the transforming growth factor-β superfamily, has been recently shown to suppress cell proliferation and to stimulate the expression of cyclin G2 (CCNG2) in human epithelial ovarian cancer cells. However, the precise mechanisms underlying these events are not fully understood. In this study, we investigated the transcriptional regulation of CCNG2 by the Nodal signaling pathway. In ovarian cancer cells, overexpression of Nodal or its receptors, activin receptor-like kinase 7 (ALK7) or ALK4, resulted in an increase in the CCNG2 promoter activity. Several putative Forkhead box class O (FoxO)3a-binding sites are present in the human CCNG2 promoter and overexpression of FoxO3a enhanced the CCNG2 promoter activity. The functional FoxO3a-binding element (FBE) was mapped to a proximal region located between -398 and -380 bp (FBE1) through deletion and mutation analyses, as well as chromatin immunoprecipitation (IP) assay. Interestingly, mutation of the FBE1 not only abolished the effect of FoxO3a, but also blocked Nodal-induced CCNG2 transcription. Nodal stimulated FoxO3a mRNA and protein expression through the canonical Smad pathway and suppressed FoxO3a inactivation by inhibiting AKT activity. Silencing of FoxO3a using small interfering RNA significantly reduced the effect of Nodal on the CCNG2 promoter activity. On the other hand, overexpression of Smad2 and Smad3 enhanced the FoxO3a-induced CCNG2 promoter activity whereas knockdown of Smad4 blocked the activity of FoxO3a. Furthermore, IP assays revealed that FoxO3a formed complexes with Smad proteins and that Nodal enhanced the binding of FoxO3a to the CCNG2 promoter. Finally, silencing of FoxO3a reversed the inhibitory effect of Nodal on cell proliferation. Taken together, these findings demonstrated that Nodal signaling promotes CCNG2 transcription by upregulating FoxO3a expression, inhibiting FoxO3a phosphorylation and enhancing its synergistic interaction with Smads. These results also suggest that FoxO3a is an important mediator of Nodal signaling in ovarian cancer cells.

  6. A three-dimensional definition of nodal spaces on the basis of CT images showing enlarged nodes for pelvic radiotherapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Portaluri, Maurizio; Bambace, Santa; Perez, Celeste

    2005-11-15

    Purpose: To demonstrate that margins of each pelvic chain may be derived by verifying the bony and soft tissue structures around abnormal nodes on computed tomography (CT) slices. Methods and Materials: Twenty consecutive patients (16 males, 4 females; mean age, 66 years; range, 43-80 years) with radiologic diagnosis of nodal involvement by histologically proved cervix carcinoma (two), rectum carcinoma (three), prostate carcinoma (four), lymphoma (five), penis carcinoma (one), corpus uteri carcinoma (one), bladder carcinoma (two), cutis tumor (one), and soft-tissue sarcoma (one) were retrospectively reviewed. One hundred CT scans showing 85 enlarged pelvic nodes were reviewed by two radiation oncologistsmore » (M.P., S.B.), and two radiologists (C.P., G.A.). Results: The more proximal structures to each enlarged node or group of nodes were thus recorded in a clockwise direction. Conclusion: According to their frequency and visibility, craniocaudal, anterior, lateral, posterior and medial margins of common iliac, external and internal iliac nodal chains, obturator and pudendal nodes, and deep and superficial inguinal nodes were derived from CT observations.« less

  7. Can axial-based nodal size criteria be used in other imaging planes to accurately determine "enlarged" head and neck lymph nodes?

    PubMed

    Bartlett, Eric S; Walters, Thomas D; Yu, Eugene

    2013-01-01

    Objective. We evaluate if axial-based lymph node size criteria can be applied to coronal and sagittal planes. Methods. Fifty pretreatment computed tomographic (CT) neck exams were evaluated in patients with head and neck squamous cell carcinoma (SCCa) and neck lymphadenopathy. Axial-based size criteria were applied to all 3 imaging planes, measured, and classified as "enlarged" if equal to or exceeding size criteria. Results. 222 lymph nodes were "enlarged" in one imaging plane; however, 53.2% (118/222) of these were "enlarged" in all 3 planes. Classification concordance between axial versus coronal/sagittal planes was poor (kappa = -0.09 and -0.07, resp., P < 0.05). The McNemar test showed systematic misclassification when comparing axial versus coronal (P < 0.001) and axial versus sagittal (P < 0.001) planes. Conclusion. Classification of "enlarged" lymph nodes differs between axial versus coronal/sagittal imaging planes when axial-based nodal size criteria are applied independently to all three imaging planes, and exclusively used without other morphologic nodal data.

  8. Can Axial-Based Nodal Size Criteria Be Used in Other Imaging Planes to Accurately Determine “Enlarged” Head and Neck Lymph Nodes?

    PubMed Central

    Bartlett, Eric S.; Walters, Thomas D.; Yu, Eugene

    2013-01-01

    Objective. We evaluate if axial-based lymph node size criteria can be applied to coronal and sagittal planes. Methods. Fifty pretreatment computed tomographic (CT) neck exams were evaluated in patients with head and neck squamous cell carcinoma (SCCa) and neck lymphadenopathy. Axial-based size criteria were applied to all 3 imaging planes, measured, and classified as “enlarged” if equal to or exceeding size criteria. Results. 222 lymph nodes were “enlarged” in one imaging plane; however, 53.2% (118/222) of these were “enlarged” in all 3 planes. Classification concordance between axial versus coronal/sagittal planes was poor (kappa = −0.09 and −0.07, resp., P < 0.05). The McNemar test showed systematic misclassification when comparing axial versus coronal (P < 0.001) and axial versus sagittal (P < 0.001) planes. Conclusion. Classification of “enlarged” lymph nodes differs between axial versus coronal/sagittal imaging planes when axial-based nodal size criteria are applied independently to all three imaging planes, and exclusively used without other morphologic nodal data. PMID:23984099

  9. A new method for true and spurious eigensolutions of arbitrary cavities using the combined Helmholtz exterior integral equation formulation method.

    PubMed

    Chen, I L; Chen, J T; Kuo, S R; Liang, M T

    2001-03-01

    Integral equation methods have been widely used to solve interior eigenproblems and exterior acoustic problems (radiation and scattering). It was recently found that the real-part boundary element method (BEM) for the interior problem results in spurious eigensolutions if the singular (UT) or the hypersingular (LM) equation is used alone. The real-part BEM results in spurious solutions for interior problems in a similar way that the singular integral equation (UT method) results in fictitious solutions for the exterior problem. To solve this problem, a Combined Helmholtz Exterior integral Equation Formulation method (CHEEF) is proposed. Based on the CHEEF method, the spurious solutions can be filtered out if additional constraints from the exterior points are chosen carefully. Finally, two examples for the eigensolutions of circular and rectangular cavities are considered. The optimum numbers and proper positions for selecting the points in the exterior domain are analytically studied. Also, numerical experiments were designed to verify the analytical results. It is worth pointing out that the nodal line of radiation mode of a circle can be rotated due to symmetry, while the nodal line of the rectangular is on a fixed position.

  10. The Effect of Anatomical Location of Lymph Node Metastases on Cancer Specific Survival in Patients with Clear Cell Renal Cell Carcinoma

    PubMed Central

    Nini, Alessandro; Larcher, Alessandro; Cianflone, Francesco; Trevisani, Francesco; Terrone, Carlo; Volpe, Alessandro; Regis, Federica; Briganti, Alberto; Salonia, Andrea; Montorsi, Francesco; Bertini, Roberto; Capitanio, Umberto

    2018-01-01

    Background Positive nodal status (pN1) is an independent predictor of survival in renal cell carcinoma (RCC) patients. However, no study to date has tested whether the location of lymph node (LN) metastases does affect oncologic outcomes in a population submitted to radical nephrectomy (RN) and extended lymph node dissection (eLND). Objective To describe nodal disease dissemination in clear cell RCC (ccRCC) patients and to assess the effect of the anatomical sites and the number of nodal areas affected on cancer specific mortality (CSM). Design, setting and partecipants The study included 415 patients who underwent RN and eLND, defined as the removal of hilar, side-specific (pre/paraaortic or pre/paracaval) and interaortocaval LNs for ccRCC, at two institutions. Outcome measurement and statistical analysis Descriptive statistics were used to depict nodal dissemination in pN1 patients, stratified according to nodal site and number of involved areas. Multivariable Cox regression analyses and Kaplan-Meier curves were used to explore the relationship between pN1 disease features and survival outcomes. Results and limitations Median number of removed LN was 14 (IQR 9–19); 23% of patients were pN1. Among patients with one involved nodal site, 54 and 26% of patients were positive only in side-specific and interaortocaval station, respectively. The most frequent nodal site was the interaortocaval and side-specific one, for right and left ccRCC, respectively. Interaortocaval nodal positivity (HR 2.3, CI 95%: 1.3–3.9, p < 0.01) represented an independent predictor of CSM. Conclusions When ccRCC patient harbour nodal disease, its spreading can occur at any nodal station without involving the others. The presence of interoartocaval positive nodes does affect oncologic outcomes. Patient summary Lymph node invasion in patients with clear cell renal cell carcinoma is not following a fixed anatomical pattern. An extended lymph node dissection, during treatment for primary kidney tumour, would aid patient risk stratification and multimodality upfront treatment. PMID:29740587

  11. Nodal aberration theory applied to freeform surfaces

    NASA Astrophysics Data System (ADS)

    Fuerschbach, Kyle; Rolland, Jannick P.; Thompson, Kevin P.

    2014-12-01

    When new three-dimensional packages are developed for imaging optical systems, the rotational symmetry of the optical system is often broken, changing its imaging behavior and making the optical performance worse. A method to restore the performance is to use freeform optical surfaces that compensate directly the aberrations introduced from tilting and decentering the optical surfaces. In order to effectively optimize the shape of a freeform surface to restore optical functionality, it is helpful to understand the aberration effect the surface may induce. Using nodal aberration theory the aberration fields induced by a freeform surface in an optical system are explored. These theoretical predications are experimentally validated with the design and implementation of an aberration generating telescope.

  12. A Web-based nomogram predicting para-aortic nodal metastasis in incompletely staged patients with endometrial cancer: a Korean Multicenter Study.

    PubMed

    Kang, Sokbom; Lee, Jong-Min; Lee, Jae-Kwan; Kim, Jae-Weon; Cho, Chi-Heum; Kim, Seok-Mo; Park, Sang-Yoon; Park, Chan-Yong; Kim, Ki-Tae

    2014-03-01

    The purpose of this study is to develop a Web-based nomogram for predicting the individualized risk of para-aortic nodal metastasis in incompletely staged patients with endometrial cancer. From 8 institutions, the medical records of 397 patients who underwent pelvic and para-aortic lymphadenectomy as a surgical staging procedure were retrospectively reviewed. A multivariate logistic regression model was created and internally validated by rigorous bootstrap resampling methods. Finally, the model was transformed into a user-friendly Web-based nomogram (http://http://www.kgog.org/nomogram/empa001.html). The rate of para-aortic nodal metastasis was 14.4% (57/397 patients). Using a stepwise variable selection, 4 variables including deep myometrial invasion, non-endometrioid subtype, lymphovascular space invasion, and log-transformed CA-125 levels were finally adopted. After 1000 repetitions of bootstrapping, all of these 4 variables retained a significant association with para-aortic nodal metastasis in the multivariate analysis-deep myometrial invasion (P = 0.001), non-endometrioid histologic subtype (P = 0.034), lymphovascular space invasion (P = 0.003), and log-transformed serum CA-125 levels (P = 0.004). The model showed good discrimination (C statistics = 0.87; 95% confidence interval, 0.82-0.92) and accurate calibration (Hosmer-Lemeshow P = 0.74). This nomogram showed good performance in predicting para-aortic metastasis in patients with endometrial cancer. The tool may be useful in determining the extent of lymphadenectomy after incomplete surgery.

  13. Is elective nodal irradiation beneficial in patients with pathologically negative lymph nodes after neoadjuvant chemotherapy and breast-conserving surgery for clinical stage II–III breast cancer? A multicentre retrospective study (KROG 12-05)

    PubMed Central

    Noh, J M; Park, W; Suh, C-O; Keum, K C; Kim, Y B; Shin, K H; Kim, K; Chie, E K; Ha, S W; Kim, S S; Ahn, S D; Shin, H S; Kim, J H; Lee, H-S; Lee, N K; Huh, S J; Choi, D H

    2014-01-01

    Background: To evaluate the effects of elective nodal irradiation (ENI) in clinical stage II–III breast cancer patients with pathologically negative lymph nodes (LNs) (ypN0) after neoadjuvant chemotherapy (NAC) followed by breast-conserving surgery (BCS) and radiotherapy (RT). Methods: We retrospectively analysed 260 patients with ypN0 who received NAC followed by BCS and RT. Elective nodal irradiation was delivered to 136 (52.3%) patients. The effects of ENI on survival outcomes were evaluated. Results: After a median follow-up period of 66.2 months (range, 15.6–127.4 months), 26 patients (10.0%) developed disease recurrence. The 5-year locoregional recurrence-free survival and disease-free survival (DFS) for all patients were 95.5% and 90.5%, respectively. Pathologic T classification (0−is vs 1 vs 2–4) and the number of LNs sampled (<13 vs ⩾13) were associated with DFS (P=0.0086 and 0.0012, respectively). There was no significant difference in survival outcomes according to ENI. Elective nodal irradiation also did not affect survival outcomes in any of the subgroups according to pathologic T classification or the number of LNs sampled. Conclusions: ENI may be omitted in patients with ypN0 breast cancer after NAC and BCS. But until the results of the randomised trials are available, patients should be put on these trials. PMID:24481403

  14. Standardizing Naming Conventions in Radiation Oncology

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Santanam, Lakshmi; Hurkmans, Coen; Mutic, Sasa

    2012-07-15

    Purpose: The aim of this study was to report on the development of a standardized target and organ-at-risk naming convention for use in radiation therapy and to present the nomenclature for structure naming for interinstitutional data sharing, clinical trial repositories, integrated multi-institutional collaborative databases, and quality control centers. This taxonomy should also enable improved plan benchmarking between clinical institutions and vendors and facilitation of automated treatment plan quality control. Materials and Methods: The Advanced Technology Consortium, Washington University in St. Louis, Radiation Therapy Oncology Group, Dutch Radiation Oncology Society, and the Clinical Trials RT QA Harmonization Group collaborated in creatingmore » this new naming convention. The International Commission on Radiation Units and Measurements guidelines have been used to create standardized nomenclature for target volumes (clinical target volume, internal target volume, planning target volume, etc.), organs at risk, and planning organ-at-risk volumes in radiation therapy. The nomenclature also includes rules for specifying laterality and margins for various structures. The naming rules distinguish tumor and nodal planning target volumes, with correspondence to their respective tumor/nodal clinical target volumes. It also provides rules for basic structure naming, as well as an option for more detailed names. Names of nonstandard structures used mainly for plan optimization or evaluation (rings, islands of dose avoidance, islands where additional dose is needed [dose painting]) are identified separately. Results: In addition to its use in 16 ongoing Radiation Therapy Oncology Group advanced technology clinical trial protocols and several new European Organization for Research and Treatment of Cancer protocols, a pilot version of this naming convention has been evaluated using patient data sets with varying treatment sites. All structures in these data sets were satisfactorily identified using this nomenclature. Conclusions: Use of standardized naming conventions is important to facilitate comparison of dosimetry across patient datasets. The guidelines presented here will facilitate international acceptance across a wide range of efforts, including groups organizing clinical trials, Radiation Oncology Institute, Dutch Radiation Oncology Society, Integrating the Healthcare Enterprise, Radiation Oncology domain (IHE-RO), and Digital Imaging and Communication in Medicine (DICOM).« less

  15. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Heijkoop, Sabrina T., E-mail: s.heijkoop@erasmusmc.nl; Langerak, Thomas R.; Quint, Sandra

    Purpose: To evaluate the clinical implementation of an online adaptive plan-of-the-day protocol for nonrigid target motion management in locally advanced cervical cancer intensity modulated radiation therapy (IMRT). Methods and Materials: Each of the 64 patients had four markers implanted in the vaginal fornix to verify the position of the cervix during treatment. Full and empty bladder computed tomography (CT) scans were acquired prior to treatment to build a bladder volume-dependent cervix-uterus motion model for establishment of the plan library. In the first phase of clinical implementation, the library consisted of one IMRT plan based on a single model-predicted internal targetmore » volume (mpITV), covering the target for the whole pretreatment observed bladder volume range, and a 3D conformal radiation therapy (3DCRT) motion-robust backup plan based on the same mpITV. The planning target volume (PTV) combined the ITV and nodal clinical target volume (CTV), expanded with a 1-cm margin. In the second phase, for patients showing >2.5-cm bladder-induced cervix-uterus motion during planning, two IMRT plans were constructed, based on mpITVs for empty-to-half-full and half-full-to-full bladder. In both phases, a daily cone beam CT (CBCT) scan was acquired to first position the patient based on bony anatomy and nodal targets and then select the appropriate plan. Daily post-treatment CBCT was used to verify plan selection. Results: Twenty-four and 40 patients were included in the first and second phase, respectively. In the second phase, 11 patients had two IMRT plans. Overall, an IMRT plan was used in 82.4% of fractions. The main reasons for selecting the motion-robust backup plan were uterus outside the PTV (27.5%) and markers outside their margin (21.3%). In patients with two IMRT plans, the half-full-to-full bladder plan was selected on average in 45% of the first 12 fractions, which was reduced to 35% in the last treatment fractions. Conclusions: The implemented online adaptive plan-of-the-day protocol for locally advanced cervical cancer enables (almost) daily tissue-sparing IMRT.« less

  16. Finite analytic numerical solution of heat transfer and flow past a square channel cavity

    NASA Technical Reports Server (NTRS)

    Chen, C.-J.; Obasih, K.

    1982-01-01

    A numerical solution of flow and heat transfer characteristics is obtained by the finite analytic method for a two dimensional laminar channel flow over a two-dimensional square cavity. The finite analytic method utilizes the local analytic solution in a small element of the problem region to form the algebraic equation relating an interior nodal value with its surrounding nodal values. Stable and rapidly converged solutions were obtained for Reynolds numbers ranging to 1000 and Prandtl number to 10. Streamfunction, vorticity and temperature profiles are solved. Local and mean Nusselt number are given. It is found that the separation streamlines between the cavity and channel flow are concave into the cavity at low Reynolds number and convex at high Reynolds number (Re greater than 100) and for square cavity the mean Nusselt number may be approximately correlated with Peclet number as Nu(m) = 0.365 Pe exp 0.2.

  17. 47 CFR 101.503 - Digital Electronic Message Service Nodal Stations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... DEMS Nodal Station licenses should specify the maximum number of 10.6 GHz DEMS User Stations to be served by that nodal station. Any increase in that number must be applied for pursuant to § 1.913 of this... Stations. 101.503 Section 101.503 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY...

  18. 47 CFR 101.503 - Digital Electronic Message Service Nodal Stations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... DEMS Nodal Station licenses should specify the maximum number of 10.6 GHz DEMS User Stations to be served by that nodal station. Any increase in that number must be applied for pursuant to § 1.913 of this... Stations. 101.503 Section 101.503 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY...

  19. 47 CFR 101.503 - Digital Electronic Message Service Nodal Stations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... DEMS Nodal Station licenses should specify the maximum number of 10.6 GHz DEMS User Stations to be served by that nodal station. Any increase in that number must be applied for pursuant to § 1.913 of this... Stations. 101.503 Section 101.503 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY...

  20. 47 CFR 101.503 - Digital Electronic Message Service Nodal Stations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... DEMS Nodal Station licenses should specify the maximum number of 10.6 GHz DEMS User Stations to be served by that nodal station. Any increase in that number must be applied for pursuant to § 1.913 of this... Stations. 101.503 Section 101.503 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY...

  1. Topological nodal-line fermions in spin-orbit metal PbTaSe2

    DOE PAGES

    Bian, Guang; Chang, Tay-Rong; Sankar, Raman; ...

    2016-02-02

    Here we discuss how topological semimetals can support one-dimensional Fermi lines or zero-dimensional Weyl points in momentum space, where the valence and conduction bands touch. While the degeneracy points in Weyl semimetals are robust against any perturbation that preserves translational symmetry, nodal lines require protection by additional crystalline symmetries such as mirror reflection. Here we report, based on a systematic theoretical study and a detailed experimental characterization, the existence of topological nodal-line states in the non-centrosymmetric compound PbTaSe 2 with strong spin-orbit coupling. Remarkably, the spin-orbit nodal lines in PbTaSe 2 are not only protected by the reflection symmetry butmore » also characterized by an integer topological invariant. Our detailed angle-resolved photoemission measurements, first-principles simulations and theoretical topological analysis illustrate the physical mechanism underlying the formation of the topological nodal-line states and associated surface states for the first time, thus paving the way towards exploring the exotic properties of the topological nodal-line fermions in condensed matter systems.« less

  2. Classification of reflection-symmetry-protected topological semimetals and nodal superconductors

    NASA Astrophysics Data System (ADS)

    Chiu, Ching-Kai; Schnyder, Andreas P.

    2014-11-01

    While the topological classification of insulators, semimetals, and superconductors in terms of nonspatial symmetries is well understood, less is known about topological states protected by crystalline symmetries, such as mirror reflections and rotations. In this work, we systematically classify topological semimetals and nodal superconductors that are protected, not only by nonspatial (i.e., global) symmetries, but also by a crystal reflection symmetry. We find that the classification crucially depends on (i) the codimension of the Fermi surface (nodal line or point) of the semimetal (superconductor), (ii) whether the mirror symmetry commutes or anticommutes with the nonspatial symmetries, and (iii) how the Fermi surfaces (nodal lines or points) transform under the mirror reflection and nonspatial symmetries. The classification is derived by examining all possible symmetry-allowed mass terms that can be added to the Bloch or Bogoliubov-de Gennes Hamiltonian in a given symmetry class and by explicitly deriving topological invariants. We discuss several examples of reflection-symmetry-protected topological semimetals and nodal superconductors, including topological crystalline semimetals with mirror Z2 numbers and topological crystalline nodal superconductors with mirror winding numbers.

  3. Maternal Gdf3 is an obligatory cofactor in Nodal signaling for embryonic axis formation in zebrafish

    PubMed Central

    Bisgrove, Brent W; Su, Yi-Chu

    2017-01-01

    Zebrafish Gdf3 (Dvr1) is a member of the TGFβ superfamily of cell signaling ligands that includes Xenopus Vg1 and mammalian Gdf1/3. Surprisingly, engineered homozygous mutants in zebrafish have no apparent phenotype. Elimination of Gdf3 in oocytes of maternal-zygotic mutants results in embryonic lethality that can be fully rescued with gdf3 RNA, demonstrating that Gdf3 is required only early in development, beyond which mutants are viable and fertile. Gdf3 mutants are refractory to Nodal ligands and Nodal repressor Lefty1. Signaling driven by TGFβ ligand Activin and constitutively active receptors Alk4 and Alk2 remain intact in gdf3 mutants, indicating that Gdf3 functions at the same pathway step as Nodal. Targeting gdf3 and ndr2 RNA to specific lineages indicates that exogenous gdf3 is able to fully rescue mutants only when co-expressed with endogenous Nodal. Together, these findings demonstrate that Gdf3 is an essential cofactor of Nodal signaling during establishment of the embryonic axis. PMID:29140249

  4. Unilateral dampening of Bmp activity by nodal generates cardiac left-right asymmetry.

    PubMed

    Veerkamp, Justus; Rudolph, Franziska; Cseresnyes, Zoltan; Priller, Florian; Otten, Cécile; Renz, Marc; Schaefer, Liliana; Abdelilah-Seyfried, Salim

    2013-03-25

    Signaling by Nodal and Bmp is essential for cardiac laterality. How activities of these pathways translate into left-right asymmetric organ morphogenesis is largely unknown. We show that, in zebrafish, Nodal locally reduces Bmp activity on the left side of the cardiac field. This effect is mediated by the extracellular matrix enzyme Hyaluronan synthase 2, expression of which is induced by Nodal. Unilateral reduction of Bmp signaling results in lower expression of nonmuscle myosin II and higher cell motility on the left, driving asymmetric displacement of the entire cardiac field. In silico modeling shows that left-right differences in cell motility are sufficient to induce a robust, directional migration of cardiac tissue. Thus, the mechanism underlying the formation of cardiac left-right asymmetry involves Nodal modulating an antimotogenic Bmp activity. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Nodal aberration theory for wild-filed asymmetric optical systems

    NASA Astrophysics Data System (ADS)

    Chen, Yang; Cheng, Xuemin; Hao, Qun

    2016-10-01

    Nodal Aberration Theory (NAT) was used to calculate the zero field position in Full Field Display (FFD) for the given aberration term. Aiming at wide-filed non-rotational symmetric decentered optical systems, we have presented the nodal geography behavior of the family of third-order and fifth-order aberrations. Meanwhile, we have calculated the wavefront aberration expressions when one optical element in the system is tilted, which was not at the entrance pupil. By using a three-piece-cellphone lens example in optical design software CodeV, the nodal geography is testified under several situations; and the wavefront aberrations are calculated when the optical element is tilted. The properties of the nodal aberrations are analyzed by using Fringe Zernike coefficients, which are directly related with the wavefront aberration terms and usually obtained by real ray trace and wavefront surface fitting.

  6. A nodal signaling pathway regulates the laterality of neuroanatomical asymmetries in the zebrafish forebrain.

    PubMed

    Concha, M L; Burdine, R D; Russell, C; Schier, A F; Wilson, S W

    2000-11-01

    Animals show behavioral asymmetries that are mediated by differences between the left and right sides of the brain. We report that the laterality of asymmetric development of the diencephalic habenular nuclei and the photoreceptive pineal complex is regulated by the Nodal signaling pathway and by midline tissue. Analysis of zebrafish embryos with compromised Nodal signaling reveals an early role for this pathway in the repression of asymmetrically expressed genes in the diencephalon. Later signaling mediated by the EGF-CFC protein One-eyed pinhead and the forkhead transcription factor Schmalspur is required to overcome this repression. When expression of Nodal pathway genes is either absent or symmetrical, neuroanatomical asymmetries are still established but are randomized. This indicates that Nodal signaling is not required for asymmetric development per se but is essential to determine the laterality of the asymmetry.

  7. Regional Nodal Irradiation in Early-Stage Breast Cancer.

    PubMed

    Whelan, Timothy J; Olivotto, Ivo A; Parulekar, Wendy R; Ackerman, Ida; Chua, Boon H; Nabid, Abdenour; Vallis, Katherine A; White, Julia R; Rousseau, Pierre; Fortin, Andre; Pierce, Lori J; Manchul, Lee; Chafe, Susan; Nolan, Maureen C; Craighead, Peter; Bowen, Julie; McCready, David R; Pritchard, Kathleen I; Gelmon, Karen; Murray, Yvonne; Chapman, Judy-Anne W; Chen, Bingshu E; Levine, Mark N

    2015-07-23

    Most women with breast cancer who undergo breast-conserving surgery receive whole-breast irradiation. We examined whether the addition of regional nodal irradiation to whole-breast irradiation improved outcomes. We randomly assigned women with node-positive or high-risk node-negative breast cancer who were treated with breast-conserving surgery and adjuvant systemic therapy to undergo either whole-breast irradiation plus regional nodal irradiation (including internal mammary, supraclavicular, and axillary lymph nodes) (nodal-irradiation group) or whole-breast irradiation alone (control group). The primary outcome was overall survival. Secondary outcomes were disease-free survival, isolated locoregional disease-free survival, and distant disease-free survival. Between March 2000 and February 2007, a total of 1832 women were assigned to the nodal-irradiation group or the control group (916 women in each group). The median follow-up was 9.5 years. At the 10-year follow-up, there was no significant between-group difference in survival, with a rate of 82.8% in the nodal-irradiation group and 81.8% in the control group (hazard ratio, 0.91; 95% confidence interval [CI], 0.72 to 1.13; P=0.38). The rates of disease-free survival were 82.0% in the nodal-irradiation group and 77.0% in the control group (hazard ratio, 0.76; 95% CI, 0.61 to 0.94; P=0.01). Patients in the nodal-irradiation group had higher rates of grade 2 or greater acute pneumonitis (1.2% vs. 0.2%, P=0.01) and lymphedema (8.4% vs. 4.5%, P=0.001). Among women with node-positive or high-risk node-negative breast cancer, the addition of regional nodal irradiation to whole-breast irradiation did not improve overall survival but reduced the rate of breast-cancer recurrence. (Funded by the Canadian Cancer Society Research Institute and others; MA.20 ClinicalTrials.gov number, NCT00005957.).

  8. Histopathological Parameters predicting Occult Nodal Metastases in Tongue Carcinoma Cases: An Indian Perspective.

    PubMed

    Jacob, Tina Elizabeth; Malathi, N; Rajan, Sharada T; Augustine, Dominic; Manish, N; Patil, Shankargouda

    2016-01-01

    It is a well-established fact that in squamous cell carcinoma cases, the presence of lymph node metastases decreased the 5-year survival rate by 50% and also caused the recurrence of the primary tumor with development of distant metastases. Till date, the predictive factors for occult cervical lymph nodes metastases in cases of tongue squamous cell carcinoma remain inconclusive. Therefore, it is imperative to identify patients who are at the greatest risk for occult cervical metastases. This study was thus performed with the aim to identify various histopathologic parameters of the primary tumor that predict occult nodal metastases. The clinicopathologic features of 56 cases of lateral tongue squamous cell carcinoma with cT1NoMo/cT2NoMo as the stage and without prior radiotherapy or chemotherapy were considered. The surgical excision of primary tumor was followed by elective neck dissection. The glossectomy specimen along with the neck nodes were fixed in formalin and 5 urn thick sections were obtained. The hematoxylin & eosin stained sections were then subjected to microscopic examination. The primary tumor characteristics that were analyzed include tumor grade, invading front, depth of tumor, lymphovascular invasion, perineural invasion and inflammatory response. The nodes were examined for possible metastases using hematoxylin & eosin followed by cytokeratin immunohistochemistry. A total of 12 cases were found with positive occult nodal metastases. On performing univariate analysis, the histopathologic parameters that were found to be statistically significant were lymphovascular invasion (p = 0.004) and perineural invasion (p = 0.003) along with a cut-off depth of infiltration more than 5 mm (p = 0.01). Histopathologic assessment of the primary tumor specimen therefore continues to provide information that is central to guide clinical management, particularly in cases of occult nodal metastases. Clinical significance The study highlights the importance of extensive histopathological screening, which holds the key for establishing occult metastases. Pathological upgrading of tumors is possible following histopathological studies similar to the present one. Presence of occult metastases justify neck dissection in these clinically N0 cases. In an Indian setting, histopathological evaluation assumes a bigger role than other expensive and advanced techniques.

  9. Tumour thickness as a predictor of nodal metastases in oral cancer: comparison between tongue and floor of mouth subsites.

    PubMed

    Balasubramanian, Deepak; Ebrahimi, Ardalan; Gupta, Ruta; Gao, Kan; Elliott, Michael; Palme, Carsten E; Clark, Jonathan R

    2014-12-01

    To identify whether tumour thickness as a predictor of nodal metastases in oral squamous cell carcinoma differs between tongue and floor of mouth (FOM) subsites. Retrospective review of 343 patients treated between 1987 and 2012. The neck was considered positive in the presence of pathologically proven nodal metastases on neck dissection or during follow-up. There were 222 oral tongue and 121 FOM tumours. In patients with FOM tumours 2.1-4mm thick, the rate of nodal metastases was 41.7%. In contrast, for tongue cancers of a similar thickness the rate was only 11.2%. This increased to 38.5% in patients with tongue cancers that were 4.1-6mm thick. Comparing these two subsites, FOM cancers cross the critical 20% threshold of probability for nodal metastases between 1 and 2mm whereas tongue cancers cross the 20% threshold just under 4mm thickness. On logistic regression adjusting for relevant covariates, there was a significant difference in the propensity for nodal metastases based on tumour thickness according to subsite (p=0.028). Thin FOM tumours (2.1-4mm) have a high rate of nodal metastases. Elective neck dissection is appropriate in FOM tumours ⩾2mm thick and in tongue tumours ⩾4mm thick. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Nodal signalling determines biradial asymmetry in Hydra.

    PubMed

    Watanabe, Hiroshi; Schmidt, Heiko A; Kuhn, Anne; Höger, Stefanie K; Kocagöz, Yigit; Laumann-Lipp, Nico; Ozbek, Suat; Holstein, Thomas W

    2014-11-06

    In bilaterians, three orthogonal body axes define the animal form, with distinct anterior-posterior, dorsal-ventral and left-right asymmetries. The key signalling factors are Wnt family proteins for the anterior-posterior axis, Bmp family proteins for the dorsal-ventral axis and Nodal for the left-right axis. Cnidarians, the sister group to bilaterians, are characterized by one oral-aboral body axis, which exhibits a distinct biradiality of unknown molecular nature. Here we analysed the biradial growth pattern in the radially symmetrical cnidarian polyp Hydra, and we report evidence of Nodal in a pre-bilaterian clade. We identified a Nodal-related gene (Ndr) in Hydra magnipapillata, and this gene is essential for setting up an axial asymmetry along the main body axis. This asymmetry defines a lateral signalling centre, inducing a new body axis of a budding polyp orthogonal to the mother polyp's axis. Ndr is expressed exclusively in the lateral bud anlage and induces Pitx, which encodes an evolutionarily conserved transcription factor that functions downstream of Nodal. Reminiscent of its function in vertebrates, Nodal acts downstream of β-Catenin signalling. Our data support an evolutionary scenario in which a 'core-signalling cassette' consisting of β-Catenin, Nodal and Pitx pre-dated the cnidarian-bilaterian split. We presume that this cassette was co-opted for various modes of axial patterning: for example, for lateral branching in cnidarians and left-right patterning in bilaterians.

  11. Pressure-induced organic topological nodal-line semimetal in the three-dimensional molecular crystal Pd (dddt) 2

    NASA Astrophysics Data System (ADS)

    Liu, Zhao; Wang, Haidi; Wang, Z. F.; Yang, Jinlong; Liu, Feng

    2018-04-01

    The nodal-line semimetal represents a class of topological materials characterized with highest band degeneracy. It is usually found in inorganic materials of high crystal symmetry or a minimum symmetry of inversion aided with accidental band degeneracy [Phys. Rev. Lett. 118, 176402 (2017), 10.1103/PhysRevLett.118.176402]. Based on first-principles band structure, Wannier charge center, and topological surface state calculations, here we predict a pressure-induced topological nodal-line semimetal in the absence of spin-orbit coupling (SOC) in the synthesized single-component 3D molecular crystal Pd (dddt) 2 . We show a Γ -centered single nodal line undulating within a narrow energy window across the Fermi level. This intriguing nodal line is generated by pressure-induced accidental band degeneracy, without protection from any crystal symmetry. When SOC is included, the fourfold degenerated nodal line is gapped and Pd (dddt) 2 becomes a strong 3D topological metal with an Z2 index of (1;000). However, the tiny SOC gap makes it still possible to detect the nodal-line properties experimentally. Our findings afford an attractive route for designing and realizing topological states in 3D molecular crystals, as they are weakly bonded through van der Waals forces with a low crystal symmetry so that their electronic structures can be easily tuned by pressure.

  12. Sensitivity and Specificity of Cardiac Tissue Discrimination Using Fiber-Optics Confocal Microscopy.

    PubMed

    Huang, Chao; Sachse, Frank B; Hitchcock, Robert W; Kaza, Aditya K

    2016-01-01

    Disturbances of the cardiac conduction system constitute a major risk after surgical repair of complex cases of congenital heart disease. Intraoperative identification of the conduction system may reduce the incidence of these disturbances. We previously developed an approach to identify cardiac tissue types using fiber-optics confocal microscopy and extracellular fluorophores. Here, we applied this approach to investigate sensitivity and specificity of human and automated classification in discriminating images of atrial working myocardium and specialized tissue of the conduction system. Two-dimensional image sequences from atrial working myocardium and nodal tissue of isolated perfused rodent hearts were acquired using a fiber-optics confocal microscope (Leica FCM1000). We compared two methods for local application of extracellular fluorophores: topical via pipette and with a dye carrier. Eight blinded examiners evaluated 162 randomly selected images of atrial working myocardium (n = 81) and nodal tissue (n = 81). In addition, we evaluated the images using automated classification. Blinded examiners achieved a sensitivity and specificity of 99.2 ± 0.3% and 98.0 ± 0.7%, respectively, with the dye carrier method of dye application. Sensitivity and specificity was similar for dye application via a pipette (99.2 ± 0.3% and 94.0 ± 2.4%, respectively). Sensitivity and specificity for automated methods of tissue discrimination were similarly high. Human and automated classification achieved high sensitivity and specificity in discriminating atrial working myocardium and nodal tissue. We suggest that our findings facilitate clinical translation of fiber-optics confocal microscopy as an intraoperative imaging modality to reduce the incidence of conduction disturbances during surgical correction of congenital heart disease.

  13. The role of elective-nodal irradiation for esthesioneuroblastoma patients with clinically negative neck

    PubMed Central

    Jiang, Wen; Mohamed, Abdallah Sherif; Fuller, Clifton David; Kim, Betty Y.S.; Tang, Chad; Gunn, G. Brandon; Hanna, Ehab Y.; Frank, Steven J.; Su, Shirley Y.; Diaz, Eduardo; Kupferman, Michael E.; Beadle, Beth M.; Morrison, William H.; Skinner, Heath; Lai, Stephen Y.; El-Naggar, Adel K.; DeMonte, Franco; Rosenthal, David I.; Garden, Adam S.; Phan, Jack

    2017-01-01

    Purpose Although adjuvant radiation to the tumor bed has been reported to improve the clinic outcomes of esthesioneuroblastoma (ENB) patients, the role of elective neck irradiation (ENI) in clinically node negative (N0) patients remains controversial. Here, we evaluated the effects of ENI on neck nodal relapse risk in ENB patients treated with radiotherapy as a component of multi-modality treatment. Methods and Materials Seventy-one N0 ENB patients irradiated at XXXXXXXXX between 1970 and 2013 were identified. ENI was performed on 22 of these patients (31%). Survival analysis was performed with focus on comparative outcomes of those patients who did and did not receive ENI. Results The median follow up time for our cohort is 80.8 months (range 6 – 350 month). Among N0 patients, 13 (18.3%) developed neck nodal relapses, with a median time to progression of 62.5 months. None of these 13 patients received prophylactic neck irradiation. ENI was associated with significantly improved regional nodal control at 5-year (regional control rate of 100% for ENI vs 82%, p < 0.001), but not overall survival or disease-free survival. Eleven patients without ENI developed isolated neck recurrences. All had further treatment for their neck disease, including neck dissection (n=10), radiation (n=10), or chemotherapy (n=5). Six of these 11 patients (54.5%) demonstrated no evidence of further recurrence with a median follow up of 55.5 month. Conclusion ENI significantly reduces the risk of cervical nodal recurrence in ENB patients with clinically N0 neck but this did not translate to a survival benefit. Multimodality treatment for isolated neck recurrence provides a reasonable salvage rate. The greatest benefit for ENI appeared to be among younger patients who presented with Kadish C disease. Further studies are needed to confirm these findings. PMID:26979544

  14. Three-dimensional conformal radiation for esophageal squamous cell carcinoma with involved-field irradiation may deliver considerable doses of incidental nodal irradiation

    PubMed Central

    2012-01-01

    Background To quantify the incidental irradiation dose to esophageal lymph node stations when irradiating T1-4N0M0 thoracic esophageal squamous cell carcinoma (ESCC) patients with a dose of 60 Gy/30f. Methods Thirty-nine patients with medically inoperable T1–4N0M0 thoracic ESCC were treated with three-dimensional conformal radiation (3DCRT) with involved-field radiation (IFI). The conformal clinical target volume (CTV) was re-created using a 3-cm margin in the proximal and distal direction beyond the barium esophagogram, endoscopic examination and CT scan defined the gross tumor volume (GTV) and a 0.5-cm margin in the lateral and anteroposterior directions of the CT scan-defined GTV. The PTV encompassed 1-cm proximal and distal margins and 0.5-cm radial margin based on the CTV. Nodal regions were delineated using the Japanese Society for Esophageal Diseases (JSED) guidelines and an EORTC-ROG expert opinion. The equivalent uniform dose (EUD) and other dosimetric parameters were calculated for each nodal station. Nodal regions with a metastasis rate greater than 5% were considered a high-risk lymph node subgroup. Results Under a 60 Gy dosage, the median Dmean and EUD was greater than 40 Gy in most high-risk nodal regions except for regions of 104, 106tb-R in upper-thoracic ESCC and 101, 104-R, 105, 106rec-L, 2, 3&7 in middle-thoracic ESCC and 107, 3&7 in lower-thoracic ESCC. In the regions with an EUD less than 40Gy, most incidental irradiation doses were significantly associated with esophageal tumor length and location. Conclusions Lymph node stations near ESCC receive considerable incidental irradiation doses with involved-field irradiation that may contribute to the elimination of subclinical lesions. PMID:23186308

  15. Nodal lines and nodal loops in nonsymmorphic odd-parity superconductors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Micklitz, T.; Norman, M. R.

    2017-01-01

    We discuss the nodal structure of odd-parity superconductors in the presence of nonsymmorphic crystal symmetries, both with and without spin-orbit coupling, and with and without time-reversal symmetry. We comment on the relation of our work to previous work in the literature, and also the implications for unconventional superconductors such as UPt3.

  16. Patterns of failure after the reduced volume approach for elective nodal irradiation in nasopharyngeal carcinoma.

    PubMed

    Seol, Ki Ho; Lee, Jeong Eun

    2016-03-01

    To evaluate the patterns of nodal failure after radiotherapy (RT) with the reduced volume approach for elective neck nodal irradiation (ENI) in nasopharyngeal carcinoma (NPC). Fifty-six NPC patients who underwent definitive chemoradiotherapy with the reduced volume approach for ENI were reviewed. The ENI included retropharyngeal and level II lymph nodes, and only encompassed the echelon inferior to the involved level to eliminate the entire neck irradiation. Patients received either moderate hypofractionated intensity-modulated RT for a total of 72.6 Gy (49.5 Gy to elective nodal areas) or a conventional fractionated three-dimensional conformal RT for a total of 68.4-72 Gy (39.6-45 Gy to elective nodal areas). Patterns of failure, locoregional control, and survival were analyzed. The median follow-up was 38 months (range, 3 to 80 months). The out-of-field nodal failure when omitting ENI was none. Three patients developed neck recurrences (one in-field recurrence in the 72.6 Gy irradiated nodal area and two in the elective irradiated region of 39.6 Gy). Overall disease failure at any site developed in 11 patients (19.6%). Among these, there were six local failures (10.7%), three regional failures (5.4%), and five distant metastases (8.9%). The 3-year locoregional control rate was 87.1%, and the distant failure-free rate was 90.4%; disease-free survival and overall survival at 3 years was 80% and 86.8%, respectively. No patient developed nodal failure in the omitted ENI site. Our investigation has demonstrated that the reduced volume approach for ENI appears to be a safe treatment approach in NPC.

  17. Omitting elective nodal irradiation during thoracic irradiation in limited-stage small cell lung cancer--evidence from a phase II trial.

    PubMed

    Colaco, Rovel; Sheikh, Hamid; Lorigan, Paul; Blackhall, Fiona; Hulse, Paul; Califano, Raffaele; Ashcroft, Linda; Taylor, Paul; Thatcher, Nicholas; Faivre-Finn, Corinne

    2012-04-01

    Omitting elective nodal irradiation (ENI) in limited-stage disease small cell lung cancer (LD-SCLC) is expected to result in smaller radiation fields. We report on data from a randomised phase II trial that omitted ENI in patients receiving concurrent chemo-radiotherapy for LD-SCLC. 38 patients with LD-SCLC were randomised to receive once-daily (66 Gy in 33 fractions) or twice-daily (45 Gy in 30 fractions) radiotherapy (RT). 3D-conformal RT was given concurrently with cisplatin and etoposide starting with the second cycle of a total of four cycles. The gross tumour volume was defined as primary tumour with involved lymph nodes (nodes ≥1 cm in short axis) identifiable with CT imaging. ENI was not used. Six recurrence patterns were identified: recurrence within planning target volume (PTV) only, recurrence within PTV+regional nodal recurrence and/or distant recurrence, isolated nodal recurrence outside PTV, nodal recurrence outside PTV+distant recurrence, distant metastases only and no recurrence. At median follow-up 16.9 months, 31/38 patients were evaluable and 14/31 patients had relapsed. There were no isolated nodal recurrences. Eight patients relapsed with intra-thoracic disease: 2 within PTV only, 4 within PTV and distantly and 2 with nodal recurrence outside PTV plus distant metastases. Rates of grade 3+ acute oesophagitis and pneumonitis in the 31 evaluable patients were 23 and 3% respectively. In our study of LD-SCLC, omitting ENI based on CT imaging was not associated with a high risk of isolated nodal recurrence, although further prospective studies are needed to confirm this. Routine ENI omission will be further evaluated prospectively in the ongoing phase III CONVERT trial (NCT00433563). Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  18. Topological transport in Dirac nodal-line semimetals

    NASA Astrophysics Data System (ADS)

    Rui, W. B.; Zhao, Y. X.; Schnyder, Andreas P.

    2018-04-01

    Topological nodal-line semimetals are characterized by one-dimensional Dirac nodal rings that are protected by the combined symmetry of inversion P and time-reversal T . The stability of these Dirac rings is guaranteed by a quantized ±π Berry phase and their low-energy physics is described by a one-parameter family of (2+1)-dimensional quantum field theories exhibiting the parity anomaly. Here we study the Berry-phase supported topological transport of P T -invariant nodal-line semimetals. We find that small inversion breaking allows for an electric-field-induced anomalous transverse current, whose universal component originates from the parity anomaly. Due to this Hall-like current, carriers at opposite sides of the Dirac nodal ring flow to opposite surfaces when an electric field is applied. To detect the topological currents, we propose a dumbbell device, which uses surface states to filter charges based on their momenta. Suggestions for experiments and device applications are discussed.

  19. Toddler signaling regulates mesodermal cell migration downstream of Nodal signaling

    PubMed Central

    Norris, Megan L; Pauli, Andrea; Gagnon, James A; Lord, Nathan D; Rogers, Katherine W; Mosimann, Christian; Zon, Leonard I

    2017-01-01

    Toddler/Apela/Elabela is a conserved secreted peptide that regulates mesendoderm development during zebrafish gastrulation. Two non-exclusive models have been proposed to explain Toddler function. The ‘specification model’ postulates that Toddler signaling enhances Nodal signaling to properly specify endoderm, whereas the ‘migration model’ posits that Toddler signaling regulates mesendodermal cell migration downstream of Nodal signaling. Here, we test key predictions of both models. We find that in toddler mutants Nodal signaling is initially normal and increasing endoderm specification does not rescue mesendodermal cell migration. Mesodermal cell migration defects in toddler mutants result from a decrease in animal pole-directed migration and are independent of endoderm. Conversely, endodermal cell migration defects are dependent on a Cxcr4a-regulated tether of the endoderm to mesoderm. These results suggest that Toddler signaling regulates mesodermal cell migration downstream of Nodal signaling and indirectly affects endodermal cell migration via Cxcr4a-signaling. PMID:29117894

  20. Hybrid nodal loop metal: Unconventional magnetoresponse and material realization

    NASA Astrophysics Data System (ADS)

    Zhang, Xiaoming; Yu, Zhi-Ming; Lu, Yunhao; Sheng, Xian-Lei; Yang, Hui Ying; Yang, Shengyuan A.

    2018-03-01

    A nodal loop is formed by a band crossing along a one-dimensional closed manifold, with each point on the loop a linear nodal point in the transverse dimensions, and can be classified as type I or type II depending on the band dispersion. Here, we propose a class of nodal loops composed of both type-I and type-II points, which are hence termed as hybrid nodal loops. Based on first-principles calculations, we predict the realization of such loops in the existing electride material Ca2As . For a hybrid loop, the Fermi surface consists of coexisting electron and hole pockets that touch at isolated points for an extended range of Fermi energies, without the need for fine-tuning. This leads to unconventional magnetic responses, including the zero-field magnetic breakdown and the momentum-space Klein tunneling observable in the magnetic quantum oscillations, as well as the peculiar anisotropy in the cyclotron resonance.

  1. Nodal patterning without Lefty inhibitory feedback is functional but fragile

    PubMed Central

    Gagnon, James A; Pauli, Andrea; Zimmerman, Steven; Aksel, Deniz C; Reyon, Deepak; Tsai, Shengdar Q; Joung, J Keith

    2017-01-01

    Developmental signaling pathways often activate their own inhibitors. Such inhibitory feedback has been suggested to restrict the spatial and temporal extent of signaling or mitigate signaling fluctuations, but these models are difficult to rigorously test. Here, we determine whether the ability of the mesendoderm inducer Nodal to activate its inhibitor Lefty is required for development. We find that zebrafish lefty mutants exhibit excess Nodal signaling and increased specification of mesendoderm, resulting in embryonic lethality. Strikingly, development can be fully restored without feedback: Lethal patterning defects in lefty mutants can be rescued by ectopic expression of lefty far from its normal expression domain or by spatially and temporally uniform exposure to a Nodal inhibitor drug. While drug-treated mutants are less tolerant of mild perturbations to Nodal signaling levels than wild type embryos, they can develop into healthy adults. These results indicate that patterning without inhibitory feedback is functional but fragile. PMID:29215332

  2. Postoperative Radiotherapy for Maxillary Sinus Cancer: Long-Term Outcomes and Toxicities of Treatment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bristol, Ian J.; Ahamad, Anesa; Garden, Adam S.

    2007-07-01

    Purpose: To determine the effects of three changes in radiotherapy technique on the outcomes for patients irradiated postoperatively for maxillary sinus cancer. Methods and Materials: The data of 146 patients treated between 1969 and 2002 were reviewed. The patients were separated into two groups according to the date of treatment. Group 1 included 90 patients treated before 1991 and Group 2 included 56 patients treated after 1991, when the three changes were implemented. The outcomes were compared between the two groups. Results: No differences were found in the 5-year overall survival, recurrence-free survival, local control, nodal control, or distant metastasismore » rates between the two groups (51% vs. 62%, 51% vs. 57%, 76% vs. 70%, 82% vs. 83%, and 28% vs. 17% for Groups 1 and 2, respectively). The three changes were to increase the portals to cover the base of the skull in patients with perineural invasion, reducing their risk of local recurrence; the addition of elective neck irradiation in patients with squamous or undifferentiated histologic features, improving the nodal control, distant metastasis, and recurrence-free survival rates (64% vs. 93%, 20% vs. 3%, and 45% vs. 67%, respectively; p < 0.05 for all comparisons); and improving the dose distributions within the target volume, reducing the late Grade 3-4 complication rates (34% in Group 1 vs. 8% in Group 2, p = 0.014). Multivariate analysis revealed advancing age, the need for enucleation, and positive margins as independent predictors of worse overall survival. The need for enucleation also predicted for worse local control. Conclusion: The three changes in radiotherapy technique improved the outcomes for select patients as predicted. Despite these changes, little demonstrable overall improvement occurred in local control or survival for these patients and additional work must be done.« less

  3. Phase II Trial of Hyperfractionated Intensity-Modulated Radiation Therapy and Concurrent Weekly Cisplatin for Stage III and IVa Head-and-Neck Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Maguire, Patrick D., E-mail: pmaguire@nhroc.co; Papagikos, Michael; Hamann, Sue

    2011-03-15

    Purpose: To investigate a novel chemoradiation regimen designed to maximize locoregional control (LRC) and minimize toxicity for patients with advanced head-and-neck squamous cell carcinoma (HNSCC). Methods and Materials: Patients received hyperfractionated intensity modulated radiation therapy (HIMRT) in 1.25-Gy fractions b.i.d. to 70 Gy to high-risk planning target volume (PTV). Intermediate and low-risk PTVs received 60 Gy and 50 Gy, at 1.07, and 0.89 Gy per fraction, respectively. Concurrent cisplatin 33 mg/m{sup 2}/week was started Week 1. Patients completed the Quality of Life Radiation Therapy Instrument pretreatment (PRE), at end of treatment (EOT), and at 1, 3, 6, 9, and 12more » months. Overall survival (OS), progression-free (PFS), LRC, and toxicities were assessed. Results: Of 39 patients, 30 (77%) were alive without disease at median follow-up of 37.5 months. Actuarial 3-year OS, PFS, and LRC were 80%, 82%, and 87%, respectively. No failures occurred in the electively irradiated neck and there were no isolated neck failures. Head and neck QOL was significantly worse in 18 of 35 patients (51%): mean 7.8 PRE vs. 3.9 EOT. By month 1, H and N QOL returned near baseline (mean 6.2, SD = 1.7). The most common acute Grade 3+ toxicities were mucositis (38%), fatigue (28%), dysphagia (28%), and leukopenia (26%). Conclusions: Hyperfractionated IMRT with low-dose weekly cisplatin resulted in good LRC with acceptable toxicity and QOL. Lack of elective nodal failures despite very low dose per fraction has led to an attempt to further minimize toxicity by reducing elective nodal doses in our subsequent protocol.« less

  4. Preoperative N Staging of Gastric Cancer by Stomach Protocol Computed Tomography

    PubMed Central

    Kim, Se Hoon; Kim, Jeong Jae; Lee, Jeong Sub; Kim, Seung Hyoung; Kim, Bong Soo; Maeng, Young Hee; Hyun, Chang Lim; Kim, Min Jeong

    2013-01-01

    Purpose Clinical stage of gastric cancer is currently assessed by computed tomography. Accurate clinical staging is important for the tailoring of therapy. This study evaluated the accuracy of clinical N staging using stomach protocol computed tomography. Materials and Methods Between March 2004 and November 2012, 171 patients with gastric cancer underwent preoperative stomach protocol computed tomography (Jeju National University Hospital; Jeju, Korea). Their demographic and clinical characteristics were reviewed retrospectively. Two radiologists evaluated cN staging using axial and coronal computed tomography images, and cN stage was matched with pathologic results. The diagnostic accuracy of stomach protocol computed tomography for clinical N staging and clinical characteristics associated with diagnostic accuracy were evaluated. Results The overall accuracy of stomach protocol computed tomography for cN staging was 63.2%. Computed tomography images of slice thickness 3.0 mm had a sensitivity of 60.0%; a specificity of 89.6%; an accuracy of 78.4%; and a positive predictive value of 78.0% in detecting lymph node metastases. Underestimation of cN stage was associated with larger tumor size (P<0.001), undifferentiated type (P=0.003), diffuse type (P=0.020), more advanced pathologic stage (P<0.001), and larger numbers of harvested and metastatic lymph nodes (P<0.001 each). Tumor differentiation was an independent factor affecting underestimation by computed tomography (P=0.045). Conclusions Computed tomography with a size criterion of 8 mm is highly specific but relatively insensitive in detecting nodal metastases. Physicians should keep in mind that computed tomography may not be an appropriate tool to detect nodal metastases for choosing appropriate treatment. PMID:24156034

  5. Role of Adjuvant Chemoradiotherapy for Ampulla of Vater Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kim, Kyubo; Chie, Eui Kyu; Jang, Jin-Young

    2009-10-01

    Purpose: To evaluate the role of adjuvant chemoradiotherapy for ampulla of Vater cancer. Methods and Materials: Between January 1991 and December 2002, 118 patients with ampulla of Vater cancer underwent en bloc resection. Forty-one patients received adjuvant chemoradiotherapy [RT(+) group], and 77 did not [RT(-) group]. Postoperative radiotherapy was delivered to the tumor bed and regional lymph nodes, for a total dose of up to 40 Gy delivered in 2-Gy fractions, with a planned 2-week rest period halfway through the treatment period. Intravenous 5-fluorouracil (500 mg/m{sup 2}/day) was given on Days 1 to 3 of each split course. The medianmore » follow-up was 65 months. Results: The 5-year overall survival rate in the RT(-) and RT(+) groups was 66.9% and 52.8%, respectively (p = 0.2225). The 5-year locoregional relapse-free survival rate in the RT(-) and RT(+) groups was 79.9% and 80.2%, respectively (p = 0.9582). When age, type of operation, T stage, N stage, histologic differentiation, and the use of adjuvant chemoradiotherapy were incorporated into the Cox proportional hazard model, there was an improvement in the locoregional relapse-free survival rate (p = 0.0050) and a trend toward a longer overall survival (p = 0.0762) associated with the use of adjuvant chemoradiotherapy. Improved overall survival (p = 0.0235) and locoregional relapse-free survival (p = 0.0095) were also evident in patients with nodal metastasis. In contrast, enhanced locoregional control (p = 0.0319) did not result in longer survival in patients with locally advanced disease (p = 0.4544). Conclusions: Adjuvant chemoradiotherapy may enhance locoregional control and overall survival in patients with ampulla of Vater cancer after curative resection, especially in those with nodal involvement.« less

  6. Squamous Cell Carcinoma of the Anal Canal: Patterns and Predictors of Failure and Implications for Intensity-Modulated Radiation Treatment Planning

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wright, Jean L., E-mail: jwright3@med.miami.ed; Patil, Sujata M.; Temple, Larissa K.F.

    2010-11-15

    Purpose: Intensity-modulated radiation treatment (IMRT) is increasingly used in the treatment of squamous cell carcinoma of the anal canal (SCCAC). Prevention of locoregional failure (LRF) using IMRT requires appropriate clinical target volume (CTV) definition. To better define the CTV for IMRT, we evaluated patterns and predictors of LRF in SCCAC patients given conventional radiation treatment. Methods and Materials: We reviewed records of 180 SCCAC patients treated with conventional radiation with or without chemotherapy at our institution between January 1990 and March 2007. All patients received radiation; the median primary tumor dose was 45 Gy. A total of 173 patients alsomore » received mitomycin-based chemotherapy. Results: Median follow-up was 40 months. Actuarial 3-year colostomy-free survival was 89% and overall survival (OS) 88%. Actuarial 3-year LRF was 23%. A total of 45 patients had LRF, with 35 (78%) occurring locally in the primary site (25 local only, 10 local and regional); however, 20 (44%) had regional components of failure within the pelvis or inguinal nodes (10 regional only, 10 local and regional). Cumulative sites of LRF (patients may have one or more site of failure) were as follows: primary, 35; inguinal, 8; external perianal, 5; common iliac, 4; presacral, 3; distal rectum, 2; external iliac, 2; and internal iliac, 2. All patients with common iliac failure had cT3 or N+ disease. Conclusions: The observed patterns of failure support inclusion of the inguinal and all pelvic nodal groups in the CTV for IMRT. In patients with advanced tumor or nodal stage, common iliac nodes should also be included in the CTV.« less

  7. An institutional approach to support the conduct and use of health policy and systems research: The Nodal Institute in the Eastern Mediterranean Region.

    PubMed

    El-Jardali, Fadi; Saleh, Shadi; Khodor, Rawya; Abu Al Rub, Raeda; Arfa, Chokri; Ben Romdhane, Habiba; Hamadeh, Randah R

    2015-10-01

    The use of health policy and systems research (HPSR) to support decision making in health systems is limited in the Eastern Mediterranean Region (EMR). This is partly due to the lack of effective initiatives to strengthen regional HPSR capacities and promote its use in decision making. This paper offers a structured reflection on the establishment and core functioning of a HPSR Nodal Institute for the EMR with specific focus on the approach used to support the conduct and use of HPSR. It seeks to gain better understanding of the activities conducted by the Nodal Institute, the methods by which the Nodal Institute implemented these activities, and the outcomes of these activities. A multi-faceted approach was implemented by the Nodal Institute in collaboration with regional academic/research institutions, Sub-Nodes. The overall approach was a phased one that included the selection of Sub-Nodes, mapping of academic/research institutions in the EMR, stakeholders' meetings, and HPSR capacity building workshops, and culminated with a regional meeting. The mapping of academic/research institutions in the EMR resulted in the identification of 50 institutions, of which only 32 were engaged in HPSR. These institutions have the highest HPSR involvement in information/evidence (84%) and the lowest in human resources for health (34%). Their main HPSR focus areas included quality of healthcare services, patient safety, management of non-communicable diseases, and human resources for health. Regional HPSR challenges among these institutions were identified. The validation and ranking questionnaires resulted in the identification of country-specific HPSR priorities according to stakeholders in three countries. From these results, cross-cutting HPSR priorities among the countries related to primary healthcare, non-communicable diseases, human resources for health, as well as cross-cutting HPSR priorities among stakeholders and according to stakeholders of the countries, were extracted. The Nodal Institute in the EMR is a promising initiative to support the conduct and use of HPSR in health policies. The approach and findings reported in this paper allow for the development of opportunities towards the building of capacity for HPSR in the region and other countries and provide a roadmap for academic/research institutions interested in HPSR in the region.

  8. Identification of lesion and nodal resistance in pea (Pisum sativum L.) to Sclerotinia sclerotiorum using genome-wide association studies and RNA-Seq

    USDA-ARS?s Scientific Manuscript database

    Nodal resistance in plants is a phenomenon where a fungal infection is prevented from passing through a node and the infection is limited to an internode region. Nodal resistance has been observed in some pathosystems such as the pea (Pisum sativum L.)-white mold (WM) (Sclerotinia sclerotiorum (Lib....

  9. Brady's Geothermal Field - Map of DAS, Nodal, Vibroseis and Reftek Station Deployment

    DOE Data Explorer

    Kurt Feigl

    2016-10-15

    Map of DAS, nodal, vibroseis and Reftek stations during March 2016 deployment. The plot on the left has nodal stations labeled; the plot on the right has vibroseis observations labeled. Stations are shown in map-view using Brady's rotated X-Y coordinates with side plots denoting elevation with respect to the WGS84 ellipsoid. Blue circles denote vibroseis data, x symbols denote DAS (cyan for horizontal and magenta for vertical), black asterisks denote Reftek data, and red plus signs denote nodal data. This map can be found on UW-Madison's askja server at /PoroTomo/DATA/MAPS/Deployment_Stations.pdf

  10. Integration of nodal and BMP signals in the heart requires FoxH1 to create left-right differences in cell migration rates that direct cardiac asymmetry.

    PubMed

    Lenhart, Kari F; Holtzman, Nathalia G; Williams, Jessica R; Burdine, Rebecca D

    2013-01-01

    Failure to properly establish the left-right (L/R) axis is a major cause of congenital heart defects in humans, but how L/R patterning of the embryo leads to asymmetric cardiac morphogenesis is still unclear. We find that asymmetric Nodal signaling on the left and Bmp signaling act in parallel to establish zebrafish cardiac laterality by modulating cell migration velocities across the L/R axis. Moreover, we demonstrate that Nodal plays the crucial role in generating asymmetry in the heart and that Bmp signaling via Bmp4 is dispensable in the presence of asymmetric Nodal signaling. In addition, we identify a previously unappreciated role for the Nodal-transcription factor FoxH1 in mediating cell responsiveness to Bmp, further linking the control of these two pathways in the heart. The interplay between these TGFβ pathways is complex, with Nodal signaling potentially acting to limit the response to Bmp pathway activation and the dosage of Bmp signals being critical to limit migration rates. These findings have implications for understanding the complex genetic interactions that lead to congenital heart disease in humans.

  11. The Bmp signaling pathway regulates development of left-right asymmetry in amphioxus.

    PubMed

    Soukup, Vladimir; Kozmik, Zbynek

    2018-02-01

    Establishment of asymmetry along the left-right (LR) body axis in vertebrates requires interplay between Nodal and Bmp signaling pathways. In the basal chordate amphioxus, the left-sided activity of the Nodal signaling has been attributed to the asymmetric morphogenesis of paraxial structures and pharyngeal organs, however the role of Bmp signaling in LR asymmetry establishment has not been addressed to date. Here, we show that Bmp signaling is necessary for the development of LR asymmetric morphogenesis of amphioxus larvae through regulation of Nodal signaling. Loss of Bmp signaling results in loss of the left-sided expression of Nodal, Gdf1/3, Lefty and Pitx and in gain of ectopic expression of Cerberus on the left side. As a consequence, the larvae display loss of the offset arrangement of axial structures, loss of the left-sided pharyngeal organs including the mouth, and ectopic development of the right-sided organs on the left side. Bmp inhibition thus phenocopies inhibition of Nodal signaling and results in the right isomerism. We conclude that Bmp and Nodal pathways act in concert to specify the left side and that Bmp signaling plays a fundamental role during LR development in amphioxus. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Initial system design method for non-rotationally symmetric systems based on Gaussian brackets and Nodal aberration theory.

    PubMed

    Zhong, Yi; Gross, Herbert

    2017-05-01

    Freeform surfaces play important roles in improving the imaging performance of off-axis optical systems. However, for some systems with high requirements in specifications, the structure of the freeform surfaces could be very complicated and the number of freeform surfaces could be large. That brings challenges in fabrication and increases the cost. Therefore, to achieve a good initial system with minimum aberrations and reasonable structure before implementing freeform surfaces is essential for optical designers. The already existing initial system design methods are limited to certain types of systems. A universal tool or method to achieve a good initial system efficiently is very important. In this paper, based on the Nodal aberration theory and the system design method using Gaussian Brackets, the initial system design method is extended from rotationally symmetric systems to general non-rotationally symmetric systems. The design steps are introduced and on this basis, two off-axis three-mirror systems are pre-designed using spherical shape surfaces. The primary aberrations are minimized using the nonlinear least-squares solver. This work provides insight and guidance for initial system design of off-axis mirror systems.

  13. The Significance of the Stromal Response in Breast Cancer: An Immunohistochemical Study of Myofibroblasts in Primary and Metastatic Breast Cancer.

    PubMed

    Roozdar, Alale; Hayes, Malcolm M; Pourseyedei, Bahram; Zeinalinejad, Hamid; Shamsi Meymandi, Manzumeh; Dabiri, Bahram; Dabiri, Shahriar

    2018-05-01

    Gene expression profiling of breast cancer has demonstrated the importance of stromal response in determining the prognosis of invasive breast cancer. The host response to breast cancer is of increasing interest to pathologists and may be a future focus for novel pharmacological treatments. This study describes the pattern of distribution of stromal myofibroblasts using immunostains for CD10 and smooth muscle actin (SMA) in 50 primary breast cancers and their matched nodal metastases (68.6% nodes positive and 31.4% nodes negative). The stroma within the tumor (intratumoral) and at the advancing tumor edge (peri-tumoral) was studied in both primary and nodal sites. A simple quantitative scoring system was employed for both immunostains. The correlation between expression of these markers by stromal cells and standard pathological prognostic factors of stage, grade, hormone receptor and Her-2 status was analysed. SMA-positive stromal cells were more abundant in peri-tumoral stroma compared with intratumoral stroma in both primary and metastatic lesions. SMA expression in the lymph node metastases showed a significant correlation with tumor stage. SMA expression in peri-tumoral stroma correlated with Her-2 status. The results of this study suggest that myofibroblasts, particularly those expressing SMA, might potentiate the progression of the carcinomatous process especially in nodal metastases. Thus these cells may be a potential therapeutic target. © 2018 The Author(s). This is an open-access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

  14. Risk Group Systems for Penile Cancer Management: A Study of 203 Patients With Invasive Squamous Cell Carcinoma.

    PubMed

    Chaux, Alcides

    2015-10-01

    To evaluate the accuracy of previously published risk group systems for predicting inguinal nodal metastases in patients with penile carcinoma. Two hundred three cases of invasive penile squamous cell carcinomas (SCC) were stratified using the following systems: Solsona et al (J Urol 2001;165:1509), Hungerhuber et al (Urology 2006;68:621), and the system proposed by the European Association of Urology (EAU; Eur Urol 2004;46:1). Receiver operating characteristic (ROC) analysis was carried out to compare accuracy in predicting final nodal status and cancer-related death. Most of cases were pT2/pT3 high-grade tumors with a small percentage of low-grade pT1 carcinomas. The metastatic rates for the Solsona et al, EAU, and Hungerhuber et al systems in the high-risk category were 15 of 73 (21%), 16 of 103 (16%), and 10 of 35 (29%) in patients with clinically negative inguinal lymph nodes and 52 of 75 (69%), 55 of 93 (59%), and 34 of 47 (72%) in patients with palpable inguinal lymph nodes, respectively. Performance by ROC analysis showed a low accuracy for all stratification systems although the Solsona et al and the Hungerhuber et al systems performed better than the EAU system. Patients in intermediate-risk categories and with clinically palpable inguinal lymph nodes were more likely to have nodal metastasis than patients with clinically negative lymph nodes in the same category. These stratification systems may be useful for patients with low-grade superficial tumors and less accurate for evaluating patients with high-grade locally advanced penile carcinomas. These data may be useful for therapeutic planning of patients with penile SCC. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Method and apparatus for routing data in an inter-nodal communications lattice of a massively parallel computer system by routing through transporter nodes

    DOEpatents

    Archer, Charles Jens; Musselman, Roy Glenn; Peters, Amanda; Pinnow, Kurt Walter; Swartz, Brent Allen; Wallenfelt, Brian Paul

    2010-11-16

    A massively parallel computer system contains an inter-nodal communications network of node-to-node links. An automated routing strategy routes packets through one or more intermediate nodes of the network to reach a destination. Some packets are constrained to be routed through respective designated transporter nodes, the automated routing strategy determining a path from a respective source node to a respective transporter node, and from a respective transporter node to a respective destination node. Preferably, the source node chooses a routing policy from among multiple possible choices, and that policy is followed by all intermediate nodes. The use of transporter nodes allows greater flexibility in routing.

  16. Practice patterns for the radical treatment of nasopharyngeal cancer by head and neck oncologists in the United Kingdom.

    PubMed

    Petkar, Imran; Bhide, Shreerang; Newbold, Kate; Harrington, Kevin; Nutting, Chris

    2018-05-01

    Advances in radiation delivery, imaging techniques, and chemotherapy have significantly improved treatment options for non-metastatic nasopharyngeal cancers (NPC). However, their impact on the practice in the United Kingdom (UK), where this tumour is rare, is unknown. This study examined the current attitudes of UK head and neck oncologists to the treatment of NPC. UK head and neck oncologists representing 19/23 cancer networks were sent an invitation email with a personalised link to a web-based survey designed to identify the influence of tumour and nodal staging on current NPC management practices. 26/42 (61%) of clinicians responded. Induction chemotherapy followed by concomitant chemoradiation was the treatment of choice for Stage III (69%) and IVa/b (96%), with cisplatin and 5-fluorouracil combination being the most commonly used induction chemotherapy regimen (88%). 16 centres (61%) used a geometric approach, adding variable margins of 0-10 mm to the gross tumour volume to define their therapeutic dose clinical target volume. 54% of respondents used 3 radiotherapy (RT) prescription doses to treat NPC. Retropharyngeal nodal region irradiation policy was inconsistent, with nearly one-quarter treating the entire group to a radical dose. Significant heterogeneity currently exists in the RT practice of NPC in the UK. A consensus regarding the optimal curative, function-sparing treatment paradigm for NPC is necessary to ensure cancer survivors have satisfactory long-term health-related quality of life. Advances in knowledge: This is the first study to highlight the significant variation in RT practice of NPC in the UK.

  17. Influence of human papillomavirus on the clinical presentation of oropharyngeal carcinoma in the United States.

    PubMed

    Stenmark, Matthew H; Shumway, Dean; Guo, Cui; Vainshtein, Jeffrey; Mierzwa, Michelle; Jagsi, Reshma; Griggs, Jennifer J; Banerjee, Mousumi

    2017-10-01

    Much of what is known about the significance of human papillomavirus (HPV) in oropharyngeal squamous cell carcinoma is derived from single-institution retrospective studies, post hoc analyses of tissue specimens from clinical trials, and tissue bank studies with a small sample size. The objective of this study is to investigate the impact of HPV on the frequency and clinical presentation of oropharyngeal carcinoma in a large, national sample with information from patients who underwent HPV testing. Retrospective, cross-sectional study. We identified a comprehensive national sample of 8,359 patients with oropharyngeal carcinoma and known HPV status diagnosed between 2010 and 2011 within the National Cancer Database. Multivariable logistic regression was used to assess correlates of patient and tumor characteristics on HPV status. Among patients with oropharyngeal carcinoma, the frequency of HPV-related squamous cell carcinoma in the United States was 65.4%. HPV-related oropharyngeal carcinoma was associated with younger age, male sex, and white race (P < 0.001). Advanced primary tumor stage was associated with HPV-negative disease (P < 0.001), whereas increasing nodal burden was associated with HPV-positive disease (P < 0.001). Despite less-advanced nodal disease, HPV-negative tumors were associated with a higher likelihood of metastasis at presentation (P < 0.001). HPV now accounts for the majority of newly diagnosed oropharyngeal carcinoma in the United States and is associated with a distinct clinical profile, supporting efforts to re-evaluate the staging and treatment paradigm for HPV-associated oropharyngeal cancer. 4. Laryngoscope, 127:2270-2278, 2017. © 2017 The American Laryngological, Rhinological and Otological Society, Inc.

  18. Topological nodal superconducting phases and topological phase transition in the hyperhoneycomb lattice

    NASA Astrophysics Data System (ADS)

    Bouhon, Adrien; Schmidt, Johann; Black-Schaffer, Annica M.

    2018-03-01

    We establish the topology of the spin-singlet superconducting states in the bare hyperhoneycomb lattice, and we derive analytically the full phase diagram using only symmetry and topology in combination with simple energy arguments. The phase diagram is dominated by two states preserving time-reversal symmetry. We find a line-nodal state dominating at low doping levels that is topologically nontrivial and exhibits surface Majorana flatbands, which we show perfectly match the bulk-boundary correspondence using the Berry phase approach. At higher doping levels, we find a fully gapped state with trivial topology. By analytically calculating the topological invariant of the nodal lines, we derive the critical point between the line-nodal and fully gapped states as a function of both pairing parameters and doping. We find that the line-nodal state is favored not only at lower doping levels but also if symmetry-allowed deformations of the lattice are present. Adding simple energy arguments, we establish that a fully gapped state with broken time-reversal symmetry likely appears covering the actual phase transition. We find this fully gapped state to be topologically trivial, while we find an additional point-nodal state at very low doing levels that also break time-reversal symmetry and has nontrivial topology with associated Fermi surface arcs. We eventually address the robustness of the phase diagram to generalized models also including adiabatic spin-orbit coupling, and we show how all but the point-nodal state are reasonably stable.

  19. Influence of FDG-PET on primary nodal target volume definition for head and neck carcinomas.

    PubMed

    van Egmond, Sylvia L; Piscaer, Vera; Janssen, Luuk M; Stegeman, Inge; Hobbelink, Monique G; Grolman, Wilko; Terhaard, Chris H

    The role of 2-[ 18 F]-fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography (PET)/computed tomography (CT) in routine diagnostic staging remains controversial. In case of discordance between FDG-PET and CT, a compromise has to be made between the risk of false positive FDG-PET and the risk of delaying appropriate salvage intervention. Second, with intensity modulated radiation therapy (IMRT), smaller radiation fields allow tissue sparing, but could also lead to more marginal failures. We retrospectively studied 283 patients with head and neck carcinoma scheduled for radiotherapy between 2002 and 2010. We analyzed the influence of FDG-PET/CT versus CT alone on defining nodal target volume definition and evaluated its long-term clinical results. Second, the location of nodal recurrences was related to the radiation regional dose distribution. In 92 patients, CT and FDG-PET, performed in mold, showed discordant results. In 33%, nodal staging was altered by FDG-PET. In 24%, FDG-PET also led to an alteration in nodal treatment, including a nodal upstage of 18% and downstage of 6%. In eight of these 92 patients, a regional recurrence occurred. Only two patients had a recurrence in the discordant node on FDG-PET and CT and both received a boost (high dose radiation). These results support the complementary value of FDG-PET/CT compared to CT alone in defining nodal target volume definition for radiotherapy of head and neck cancer.

  20. BMP inhibition by DAN in Hensen's node is a critical step for the establishment of left-right asymmetry in the chick embryo.

    PubMed

    Katsu, Kenjiro; Tokumori, Daisuke; Tatsumi, Norifumi; Suzuki, Atsushi; Yokouchi, Yuji

    2012-03-01

    During left-right (L-R) axis formation, Nodal is expressed in the node and has a central role in the transfer of L-R information in the vertebrate embryo. Bone morphogenetic protein (BMP) signaling also has an important role for maintenance of gene expression around the node. Several members of the Cerberus/Dan family act on L-R patterning by regulating activity of the transforming growth factor-β (TGF-β) family. We demonstrate here that chicken Dan plays a critical role in L-R axis formation. Chicken Dan is expressed in the left side of the node shortly after left-handed Shh expression and before the appearance of asymmetrically expressed genes in the lateral plate mesoderm (LPM). In vitro experiments revealed that DAN inhibited BMP signaling but not NODAL signaling. SHH had a positive regulatory effect on Dan expression while BMP4 had a negative effect. Using overexpression and RNA interference-mediated knockdown strategies, we demonstrate that Dan is indispensable for Nodal expression in the LPM and for Lefty-1 expression in the notochord. In the perinodal region, expression of Dan and Nodal was independent of each other. Nodal up-regulation by DAN required NODAL signaling, suggesting that DAN might act synergistically with NODAL. Our data indicate that Dan plays an essential role in the establishment of the L-R axis by inhibiting BMP signaling around the node. Copyright © 2012. Published by Elsevier Inc.

  1. Intensive field phenotyping of maize (Zea mays L.) root crowns identifies phenes and phene integration associated with plant growth and nitrogen acquisition

    PubMed Central

    York, Larry M.; Lynch, Jonathan P.

    2015-01-01

    Root architecture is an important regulator of nitrogen (N) acquisition. Existing methods to phenotype the root architecture of cereal crops are generally limited to seedlings or to the outer roots of mature root crowns. The functional integration of root phenes is poorly understood. In this study, intensive phenotyping of mature root crowns of maize was conducted to discover phenes and phene modules related to N acquisition. Twelve maize genotypes were grown under replete and deficient N regimes in the field in South Africa and eight in the USA. An image was captured for every whorl of nodal roots in each crown. Custom software was used to measure root phenes including nodal occupancy, angle, diameter, distance to branching, lateral branching, and lateral length. Variation existed for all root phenes within maize root crowns. Size-related phenes such as diameter and number were substantially influenced by nodal position, while angle, lateral density, and distance to branching were not. Greater distance to branching, the length from the shoot to the emergence of laterals, is proposed to be a novel phene state that minimizes placing roots in already explored soil. Root phenes from both older and younger whorls of nodal roots contributed to variation in shoot mass and N uptake. The additive integration of root phenes accounted for 70% of the variation observed in shoot mass in low N soil. These results demonstrate the utility of intensive phenotyping of mature root systems, as well as the importance of phene integration in soil resource acquisition. PMID:26041317

  2. Radioimmunoguided surgery in primary colon cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Nieroda, C.A.; Mojzisik, C.; Sardi, A.

    1990-01-01

    Radioimmunoguided surgery (RIGS), the intraoperative use of a hand-held gamma detecting probe (GDP) to identify tissue containing radiolabeled monoclonal antibody (MAb), was performed upon 30 patients with primary colon carcinoma. Each patient received an intravenous injection of MAb B72.3 (1.0 to 0.25 mg) radiolabeled with {sup 125}I (5.0 to 1.0 mCi) 8 to 34 days before exploration. The GDP was used to measure radioactivity in colon tissue, tumor bed, nodal drainage areas, and areas of suspected metastases. Antibody localized to histologically documented tumor in 23 of 30 patients (77%). Tumor margins were more clearly defined in 20 of 30 patientsmore » (67%). GDP counts led to major alterations in surgical resection in five patients (17%) and changes in adjuvant therapy in four (14%). GDP counts identified occult liver metastases in two patients (7%) and correctly indicated the benign nature of liver masses in three (10%). In four patients (13%), occult nodal metastases were identified. RIGS can precisely delineate tumor margins, define the extent of nodal involvement, and localize occult tumor, providing a method of immediate intraoperative staging that may lessen recurrences and produce higher survival rates.« less

  3. Long-chain bases, phosphatidic acid, MAPKs, and reactive oxygen species as nodal signal transducers in stress responses in Arabidopsis

    PubMed Central

    Saucedo-García, Mariana; Gavilanes-Ruíz, Marina; Arce-Cervantes, Oscar

    2015-01-01

    Due to their sessile condition, plants have developed sensitive, fast, and effective ways to contend with environmental changes. These mechanisms operate as informational wires conforming extensive and intricate networks that are connected in several points. The responses are designed as pathways orchestrated by molecules that are transducers of protein and non-protein nature. Their chemical nature imposes selective features such as specificity, formation rate, and generation site to the informational routes. Enzymes such as mitogen-activated protein kinases and non-protein, smaller molecules, such as long-chain bases, phosphatidic acid, and reactive oxygen species are recurrent transducers in the pleiotropic responses to biotic and abiotic stresses in plants. In this review, we considered these four components as nodal points of converging signaling pathways that start from very diverse stimuli and evoke very different responses. These pleiotropic effects may be explained by the potentiality that every one of these four mediators can be expressed from different sources, cellular location, temporality, or magnitude. Here, we review recent advances in our understanding of the interplay of these four specific signaling components in Arabidopsis cells, with an emphasis on drought, cold and pathogen stresses. PMID:25763001

  4. Dual time point 2-deoxy-2-[18F]fluoro-D-glucose PET/CT: nodal staging in locally advanced breast cancer.

    PubMed

    García Vicente, A M; Soriano Castrejón, A; Cruz Mora, M Á; Ortega Ruiperez, C; Espinosa Aunión, R; León Martín, A; González Ageitos, A; Van Gómez López, O

    2014-01-01

    To assess dual time point 2-deoxy-2-[(18)F]fluoro-D-glucose (18)(F)FDG PET-CT accuracy in nodal staging and in detection of extra-axillary involvement. Dual time point [(18)F] FDG PET/CT scan was performed in 75 patients. Visual and semiquantitative assessment of lymph nodes was performed. Semiquantitative measurement of SUV and ROC-analysis were carried out to calculate SUV(max) cut-off value with the best diagnostic performance. Axillary and extra-axillary lymph node chains were evaluated. Sensitivity and specificity of visual assessment was 87.3% and 75%, respectively. SUV(max) values with the best sensitivity were 0.90 and 0.95 for early and delayed PET, respectively. SUV(max) values with the best specificity were 1.95 and 2.75, respectively. Extra-axillary lymph node involvement was detected in 26.7%. FDG PET/CT detected extra-axillary lymph node involvement in one-fourth of the patients. Semiquantitative lymph node analysis did not show any advantage over the visual evaluation. Copyright © 2013 Elsevier España, S.L. and SEMNIM. All rights reserved.

  5. Risk Factors Associated with Disease Recurrence in Patients with Stage III/IV Squamous Cell Carcinoma of the Oral Cavity Treated with Surgery and Postoperative Radiotherapy.

    PubMed

    Noble, Anisha R; Greskovich, John F; Han, Jaehong; Reddy, Chandana A; Nwizu, Tobenna I; Khan, Mumtaz F; Scharpf, Joseph; Adelstein, David J; Burkey, Brian B; Koyfman, Shlomo A

    2016-02-01

    The purpose of the present study was to identify variables associated with high risk of failure in patients with locally advanced squamous cell carcinoma of the oral cavity (SCC-OC). This retrospective study included 191 patients with stage III-IVb SCC-OC treated with post-operative radiotherapy (RT) or chemoradiotherapy (CRT) between 1995 and 2013. Disease-free (DFS) and overall survival (OS) were analyzed; variables associated with inferior DFS were identified. Seventy-five patients (39%) recurred. DFS and five-year OS were 52% and 54%, respectively. Poorly differentiated tumors (p=0.03), recurrent tumors (p=0.02) and high nodal ratio (p=0.02) were associated with an increased risk of recurrence. CRT was associated with improved DFS in patients with positive margins and/or extracapsular extension (p=0.021). Tumors that are recurrent, high grade, or have high nodal ratio are at risk of recurrence. Presence of these disease features should be taken into consideration for better risk stratification. Copyright© 2016 International Institute of Anticancer Research (Dr. John G. Delinassios), All rights reserved.

  6. High-dose therapy and autologous stem cell transplantation for extra-nodal NK/T lymphoma in patients from the Western hemisphere: a study from the European Society for Blood and Marrow Transplantation.

    PubMed

    Fox, Christopher P; Boumendil, Ariane; Schmitz, Norbert; Finel, Herve; Luan, Jian J; Sucak, Gülsan; Blaise, Didier; Finke, Jürgen; Pflüger, Karl-Heinz; Veelken, Hendrik; Gorin, Norbert-Claude; Poiré, Xavier; Ganser, Arnold; Dreger, Peter; Sureda, Anna

    2015-01-01

    Extra-nodal NK/T lymphoma (ENKTL) is rare and more frequently encountered in East Asia. The role of high-dose therapy and autologous stem cell transplantation (HDT-ASCT) for ENKTL is unclear. Twenty-eight evaluable patients who had undergone HDT-ASCT in Europe from 2000-2009 were studied. The median age was 47 years and patients had received a median of two lines of prior therapy. Some 57% of patients were not in complete remission or beyond first complete remission at HDT-ASCT. The 1-year non-relapse mortality (NRM) was 11%; 2-year progression-free survival (PFS) and overall survival (OS) rates were 41% and 52%, respectively. Notably, the 2-year PFS and OS for those with stage III/IV disease were 33% and 40%, respectively, with no relapses beyond 1-year post-HDT-ASCT. This is the largest analysis of HDT-ASCT for patients with ENKTL reported from the Western hemisphere. Survival is comparable to East Asian cohorts and outcomes are encouraging for patients with advanced disease.

  7. Maternal nodal and zebrafish embryogenesis.

    PubMed

    Bennett, James T; Stickney, Heather L; Choi, Wen-Yee; Ciruna, Brian; Talbot, William S; Schier, Alexander F

    2007-11-08

    In fish and amphibians, the dorsal axis is specified by the asymmetric localization of maternally provided components of the Wnt signalling pathway. Gore et al. suggest that the Nodal signal Squint (Sqt) is required as a maternally provided dorsal determinant in zebrafish. Here we test their proposal and show that the maternal activities of sqt and the related Nodal gene cyclops (cyc) are not required for dorsoventral patterning.

  8. Topology optimization for three-dimensional electromagnetic waves using an edge element-based finite-element method.

    PubMed

    Deng, Yongbo; Korvink, Jan G

    2016-05-01

    This paper develops a topology optimization procedure for three-dimensional electromagnetic waves with an edge element-based finite-element method. In contrast to the two-dimensional case, three-dimensional electromagnetic waves must include an additional divergence-free condition for the field variables. The edge element-based finite-element method is used to both discretize the wave equations and enforce the divergence-free condition. For wave propagation described in terms of the magnetic field in the widely used class of non-magnetic materials, the divergence-free condition is imposed on the magnetic field. This naturally leads to a nodal topology optimization method. When wave propagation is described using the electric field, the divergence-free condition must be imposed on the electric displacement. In this case, the material in the design domain is assumed to be piecewise homogeneous to impose the divergence-free condition on the electric field. This results in an element-wise topology optimization algorithm. The topology optimization problems are regularized using a Helmholtz filter and a threshold projection method and are analysed using a continuous adjoint method. In order to ensure the applicability of the filter in the element-wise topology optimization version, a regularization method is presented to project the nodal into an element-wise physical density variable.

  9. Topology optimization for three-dimensional electromagnetic waves using an edge element-based finite-element method

    PubMed Central

    Korvink, Jan G.

    2016-01-01

    This paper develops a topology optimization procedure for three-dimensional electromagnetic waves with an edge element-based finite-element method. In contrast to the two-dimensional case, three-dimensional electromagnetic waves must include an additional divergence-free condition for the field variables. The edge element-based finite-element method is used to both discretize the wave equations and enforce the divergence-free condition. For wave propagation described in terms of the magnetic field in the widely used class of non-magnetic materials, the divergence-free condition is imposed on the magnetic field. This naturally leads to a nodal topology optimization method. When wave propagation is described using the electric field, the divergence-free condition must be imposed on the electric displacement. In this case, the material in the design domain is assumed to be piecewise homogeneous to impose the divergence-free condition on the electric field. This results in an element-wise topology optimization algorithm. The topology optimization problems are regularized using a Helmholtz filter and a threshold projection method and are analysed using a continuous adjoint method. In order to ensure the applicability of the filter in the element-wise topology optimization version, a regularization method is presented to project the nodal into an element-wise physical density variable. PMID:27279766

  10. Definition of the supraclavicular and infraclavicular nodes: implications for three-dimensional CT-based conformal radiation therapy.

    PubMed

    Madu, C N; Quint, D J; Normolle, D P; Marsh, R B; Wang, E Y; Pierce, L J

    2001-11-01

    To delineate with computed tomography (CT) the anatomic regions containing the supraclavicular (SCV) and infraclavicular (IFV) nodal groups, to define the course of the brachial plexus, to estimate the actual radiation dose received by these regions in a series of patients treated in the traditional manner, and to compare these doses to those received with an optimized dosimetric technique. Twenty patients underwent contrast material-enhanced CT for the purpose of radiation therapy planning. CT scans were used to study the location of the SCV and IFV nodal regions by using outlining of readily identifiable anatomic structures that define the nodal groups. The brachial plexus was also outlined by using similar methods. Radiation therapy doses to the SCV and IFV were then estimated by using traditional dose calculations and optimized planning. A repeated measures analysis of covariance was used to compare the SCV and IFV depths and to compare the doses achieved with the traditional and optimized methods. Coverage by the 90% isodose surface was significantly decreased with traditional planning versus conformal planning as the depth to the SCV nodes increased (P < .001). Significantly decreased coverage by using the 90% isodose surface was demonstrated for traditional planning versus conformal planning with increasing IFV depth (P = .015). A linear correlation was found between brachial plexus depth and SCV depth up to 7 cm. Conformal optimized planning provided improved dosimetric coverage compared with standard techniques.

  11. Benchmark measurements and calculations of a 3-dimensional neutron streaming experiment

    NASA Astrophysics Data System (ADS)

    Barnett, D. A., Jr.

    1991-02-01

    An experimental assembly known as the Dog-Legged Void assembly was constructed to measure the effect of neutron streaming in iron and void regions. The primary purpose of the measurements was to provide benchmark data against which various neutron transport calculation tools could be compared. The measurements included neutron flux spectra at four places and integral measurements at two places in the iron streaming path as well as integral measurements along several axial traverses. These data have been used in the verification of Oak Ridge National Laboratory's three-dimensional discrete ordinates code, TORT. For a base case calculation using one-half inch mesh spacing, finite difference spatial differencing, an S(sub 16) quadrature and P(sub 1) cross sections in the MUFT multigroup structure, the calculated solution agreed to within 18 percent with the spectral measurements and to within 24 percent of the integral measurements. Variations on the base case using a fewgroup energy structure and P(sub 1) and P(sub 3) cross sections showed similar agreement. Calculations using a linear nodal spatial differencing scheme and fewgroup cross sections also showed similar agreement. For the same mesh size, the nodal method was seen to require 2.2 times as much CPU time as the finite difference method. A nodal calculation using a typical mesh spacing of 2 inches, which had approximately 32 times fewer mesh cells than the base case, agreed with the measurements to within 34 percent and yet required on 8 percent of the CPU time.

  12. Row fault detection system

    DOEpatents

    Archer, Charles Jens [Rochester, MN; Pinnow, Kurt Walter [Rochester, MN; Ratterman, Joseph D [Rochester, MN; Smith, Brian Edward [Rochester, MN

    2008-10-14

    An apparatus, program product and method checks for nodal faults in a row of nodes by causing each node in the row to concurrently communicate with its adjacent neighbor nodes in the row. The communications are analyzed to determine a presence of a faulty node or connection.

  13. Row fault detection system

    DOEpatents

    Archer, Charles Jens [Rochester, MN; Pinnow, Kurt Walter [Rochester, MN; Ratterman, Joseph D [Rochester, MN; Smith, Brian Edward [Rochester, MN

    2012-02-07

    An apparatus, program product and method check for nodal faults in a row of nodes by causing each node in the row to concurrently communicate with its adjacent neighbor nodes in the row. The communications are analyzed to determine a presence of a faulty node or connection.

  14. On the Nodal Lines of Eisenstein Series on Schottky Surfaces

    NASA Astrophysics Data System (ADS)

    Jakobson, Dmitry; Naud, Frédéric

    2017-04-01

    On convex co-compact hyperbolic surfaces {X=Γ backslash H2}, we investigate the behavior of nodal curves of real valued Eisenstein series {F_λ(z,ξ)}, where {λ} is the spectral parameter, {ξ} the direction at infinity. Eisenstein series are (non-{L^2}) eigenfunctions of the Laplacian {Δ_X} satisfying {Δ_X F_λ=(1/4+λ^2)F_λ}. As {λ} goes to infinity (the high energy limit), we show that, for generic {ξ}, the number of intersections of nodal lines with any compact segment of geodesic grows like {λ}, up to multiplicative constants. Applications to the number of nodal domains inside the convex core of the surface are then derived.

  15. Winding numbers of nodal points in Fe-based superconductors

    NASA Astrophysics Data System (ADS)

    Chichinadze, Dmitry V.; Chubukov, Andrey V.

    2018-03-01

    We analyze the nodal points in multiorbital Fe-based superconductors from a topological perspective. We consider the s+- gap structure with accidental nodes, and the d -wave gap with nodes along the symmetry directions. In both cases, the nodal points can be moved by varying an external parameter, e.g., a degree of interpocket pairing. Eventually, the nodes merge and annihilate via a Lifshitz-type transition. We discuss the Lifshitz transition in Fe-based superconductors from a topological point of view. We show, both analytically and numerically, that the merging nodal points have winding numbers of opposite sign. This is consistent with the general reasoning that the total winding number is a conserved quantity in the Lifshitz transition.

  16. Advances in radiotherapy for esophageal cancer

    PubMed Central

    Deng, Wei

    2018-01-01

    Esophageal cancer is a common type of malignancy worldwide and usually requires multidisciplinary care. Radiotherapy plays an important part in management of the disease. During the past few years, researchers have made much progress about radiotherapy for esophageal cancer, which was revealed in every aspect of clinical practice. Neoadjuvant chemoradiotherapy remains the standard treatment for locally advanced esophageal cancer, whereas neoadjuvant chemotherapy appears to show less toxicities and non-inferior prognosis. What’s more, definitive chemoradiotherapy could be an option for non-surgical candidates and good responders to chemoradiotherapy. Advances in radiation techniques result in higher conformity, homogeneity, more normal tissue sparing and less treatment time. Promising prognoses and less toxicities were also seen in advanced techniques. As radiation dose higher than 50 Gy obtains better local control and survival, simultaneously integrated boost is designed to increase primary tumor dosage and keep prophylactic dose to subclinical areas. Elective nodal irradiation brings about better local control but do not show advantages in survival compared with involved field irradiation (IFI). As a trend, more tolerable chemoradiotherapy regimen would be taken into account in dealing with elderly patients. PMID:29666802

  17. Two highly-related regulatory subunits of PP2A exert opposite effects on TGF-β/Activin/Nodal signalling

    PubMed Central

    Batut, Julie; Schmierer, Bernhard; Cao, Jing; Raftery, Laurel A.; Hill, Caroline S.; Howell, Michael

    2016-01-01

    Summary We identify Bα (PPP2R2A) and Bδ (PPP2R2D), two highly-related members of the B family of regulatory subunits of the protein phosphatase PP2A, as important modulators of TGF-β/Activin/Nodal signalling, which affect the pathway in opposite ways. Knockdown of Bα in Xenopus embryos or mammalian tissue culture cells suppresses TGF-β/Activin/Nodal-dependent responses, whereas knockdown of Bδ enhances these responses. Moreover, in Drosophila, overexpression of Smad2 rescues a severe wing phenotype caused by overexpression of the single Drosophila PP2A B subunit, Twins. We show that in vertebrates Bα enhances TGF-β/Activin/Nodal signalling by stabilising the basal levels of type I receptor, whereas Bδ negatively modulates these pathways by restricting receptor activity. Thus, these highly-related members of the same subfamily of PP2A regulatory subunits differentially regulate TGF-β/Activin/Nodal signalling to elicit opposing biological outcomes. PMID:18697906

  18. Barrier tunneling of the loop-nodal semimetal in the hyperhoneycomb lattice

    NASA Astrophysics Data System (ADS)

    Guan, Ji-Huan; Zhang, Yan-Yang; Lu, Wei-Er; Xia, Yang; Li, Shu-Shen

    2018-05-01

    We theoretically investigate the barrier tunneling in the 3D model of the hyperhoneycomb lattice, which is a nodal-line semimetal with a Dirac loop at zero energy. In the presence of a rectangular potential, the scattering amplitudes for different injecting states around the nodal loop are calculated, by using analytical treatments of the effective model, as well as numerical simulations of the tight binding model. In the low energy regime, states with remarkable transmissions are only concentrated in a small range around the loop plane. When the momentum of the injecting electron is coplanar with the nodal loop, nearly perfect transmissions can occur for a large range of injecting azimuthal angles if the potential is not high. For higher potential energies, the transmission shows a resonant oscillation with the potential, but still with peaks being perfect transmissions that do not decay with the potential width. These strikingly robust transports of the loop-nodal semimetal can be approximately explained by a momentum dependent Dirac Hamiltonian.

  19. Integration of root phenes revealed by intensive phenotyping of root system architecture, anatomy, and physiology in cereals

    NASA Astrophysics Data System (ADS)

    York, Larry

    2015-04-01

    Food insecurity is among the greatest challenges humanity will face in the 21st century. Agricultural production in much of the world is constrained by the natural infertility of soil which restrains crops from reaching their yield potential. In developed nations, fertilizer inputs pollute air and water and contribute to climate change and environmental degradation. In poor nations low soil fertility is a primary constraint to food security and economic development. Water is almost always limiting crop growth in any system. Increasing the acquisition efficiency of soil resources is one method by which crop yields could be increased without the use of more fertilizers or irrigation. Cereals are the most widely grown crops, both in terms of land area and in yield, so optimizing uptake efficiency of cereals is an important goal. Roots are the primary interface between plant and soil and are responsible for the uptake of soil resources. The deployment of roots in space and time comprises root system architecture (RSA). Cereal RSA is a complex phenotype that aggregates many elemental phenes (elemental units of phenotype). Integration of root phenes will be determined by interactions through their effects on soil foraging and plant metabolism. Many architectural, metabolic, and physiological root phenes have been identified in maize, including: nodal root number, nodal root growth angle, lateral root density, lateral root length, aerenchyma, cortical cell size and number, and nitrate uptake kinetics. The utility of these phenes needs confirmation in maize and in other cereals. The maize root system is composed of an embryonic root system and nodal roots that emerge in successive whorls as the plant develops, and is similar to other cereals. Current phenotyping platforms often ignore the inner whorls and instead focus on the most visible outer whorls after excavating a maize root crown from soil. Here, an intensive phenotyping platform evaluating phenes of all nodal root whorls in maize is introduced, and field work demonstrated how the variation within the root crown has functional significance for nitrogen acquisition. Nodal root number was decomposed to more elemental phenes including the number of nodes and the occupancies of each node. Simulations demonstrated that root systems forming fewer nodal roots and with delayed emergence perform well in low nitrogen soils. Nitrate uptake kinetics (NUK) also varied within the maize root system, and simulations showing a lack of interaction between NUK and RSA reflects a knowledge gap in the costs of NUK at the molecular level. Finally, maize RSA among hybrids from different era periods over the past 100 years suggests evolution towards more nitrogen efficient root phene states. This work will be discussed within the context of next-generation root phenotyping of cereals, the dilemma between extensive and intensive phenotyping, and the need for linking across scales and methods.

  20. The Blended Finite Element Method for Multi-fluid Plasma Modeling

    DTIC Science & Technology

    2016-07-01

    Briefing Charts 3. DATES COVERED (From - To) 07 June 2016 - 01 July 2016 4. TITLE AND SUBTITLE The Blended Finite Element Method for Multi-fluid Plasma...BLENDED FINITE ELEMENT METHOD FOR MULTI-FLUID PLASMA MODELING Éder M. Sousa1, Uri Shumlak2 1ERC INC., IN-SPACE PROPULSION BRANCH (RQRS) AIR FORCE RESEARCH...MULTI-FLUID PLASMA MODEL 2 BLENDED FINITE ELEMENT METHOD Blended Finite Element Method Nodal Continuous Galerkin Modal Discontinuous Galerkin Model

  1. Comparison of Modal to Nodal Approaches for Wavefront Correction,

    DTIC Science & Technology

    1986-02-01

    the influence function of the wavefront corrector. (Implicit here is the assumption that the influence function is the same for every node, which is...To implement a nodal correction, the wavefront to be corrected is -. .. decomposed using a basis which is determined by the nodal (actuator) influence ... function of the wavefront corrector. This decomposition results in a set of coefficients which correspond to the drive signal required at the

  2. The distance between breast cancer and the skin is associated with axillary nodal metastasis.

    PubMed

    Eom, Yong Hwa; Kim, Eun Jin; Chae, Byung Joo; Song, Byung Joo; Jung, Sang Seol

    2015-06-01

    More superficially located tumors may be more likely than deeper tumors to metastasize to the axillary nodes via the lymphatics. The aim of this study was to determine whether breast cancer distance from the skin affects axillary node metastasis, ipsilateral breast cancer recurrence, or recurrence-free survival. A total of 1,005 consecutive patients with breast cancer who underwent surgery between January 2003 and December 2009 were selected. The distance of the tumor from the skin was measured from the skin to the most anterior hypoechoic leading edge of the lesion. In total, 603 (68%) patients had no axillary nodal metastasis, and 288 (32%) had axillary nodal metastasis. A breast cancer distance from the skin <3 mm induced more axillary nodal metastasis (P = 0.039). However, no significant correlation was observed between breast cancer distance from the skin <3 mm and ipsilateral breast cancer recurrence (P = 0.788) or recurrence-free survival (P = 0.353). Breast cancers located closer to the skin had a higher incidence of axillary nodal metastasis. Therefore, tumor distance from the skin should be considered when evaluating a patient with breast cancer and considering the risk of nodal metastasis. © 2015 Wiley Periodicals, Inc.

  3. Role of Nodal-PITX2C signaling pathway in glucose-induced cardiomyocyte hypertrophy.

    PubMed

    Su, Dongmei; Jing, Sun; Guan, Lina; Li, Qian; Zhang, Huiling; Gao, Xiaobo; Ma, Xu

    2014-06-01

    Pathological cardiac hypertrophy is a major cause of morbidity and mortality in cardiovascular disease. Recent studies have shown that cardiomyocytes, in response to high glucose (HG) stimuli, undergo hypertrophic growth. While much work still needs to be done to elucidate this important mechanism of hypertrophy, previous works have showed that some pathways or genes play important roles in hypertrophy. In this study, we showed that sublethal concentrations of glucose (25 mmol/L) could induce cardiomyocyte hypertrophy with an increase in the cellular surface area and the upregulation of the atrial natriuretic peptide (ANP) gene, a hypertrophic marker. High glucose (HG) treatments resulted in the upregulation of the Nodal gene, which is under-expressed in cardiomyocytes. We also determined that the knockdown of the Nodal gene resisted HG-induced cardiomyocyte hypertrophy. The overexpression of Nodal was able to induce hypertrophy in cardiomyocytes, which was associated with the upregulation of the PITX2C gene. We also showed that increases in the PITX2C expression, in response to Nodal, were mediated by the Smad4 signaling pathway. This study is highly relevant to the understanding of the effects of the Nodal-PITX2C pathway on HG-induced cardiomyocyte hypertrophy, as well as the related molecular mechanisms.

  4. How do I deal with the axilla in patients with a positive sentinel lymph node?

    PubMed

    Falkson, Conrad B

    2011-12-01

    Optimal management of the axilla in a patient with a positive sentinel node biopsy is not yet defined.These patients usually have Breast Conserving Surgery and receive adjuvant systemic therapy and whole breast radiation.Treatment options for the axilla include: no further surgery with or without radiation completion axillary nodal dissection with or without radiation Radiation options in addition to whole breast radiation include axillary and supraclavicular nodal irradiation regional nodal irradiationincludes supraclavicular and internal mammary nodes Completion axillary dissection has been standard practice in patients with positive sentinel nodes. the number of involved nodes provides prognostic information. theoretically improves local control, but may be obviated by systemic chemotherapy. but avoidance of dissection may not adversely affect locoregional control or survival. dissection has significant morbidity so safe avoidance is desirable. There is little worldwide concordance on the use of radiation: whole breast radiation (commonly used after breast conserving surgery) may radiate the lower axilla supraclavicular radiation is most commonly recommended for patients with four or more nodes but may confer a survival benefit on patients with lower risk disease. adding nodal irradiation reduces local recurrence with only modest toxicity. Adjuvant systemic therapy provides a survival benefit for patients with nodal disease. Most will receive cytostatic chemotherapy containing an anthracycline and a taxane. Hormone therapy is appropriate for estrogen receptor positive disease. The extent to which systemic therapy controls microscopic nodal disease is unknown. Node positive patients should generally receive adjuvant chemotherapy.A small group of patients benefit from specific nodal therapy. Further studies are needed to better identify these patients.

  5. The Accuracy of Integrated [18F] Fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography in Detection of Pelvic and Para-aortic Nodal Metastasis in Patients with High Risk Endometrial Cancer

    PubMed Central

    Gholkar, Nikhil Shirish; Saha, Subhas Chandra; Prasad, GRV; Bhattacharya, Anish; Srinivasan, Radhika; Suri, Vanita

    2014-01-01

    Lymph nodal (LN) metastasis is the most important prognostic factor in high-risk endometrial cancer. However, the benefit of routine lymphadenectomy in endometrial cancer is controversial. This study was conducted to assess the accuracy of [18F] fluorodeoxyglucose-positron emission tomography/computed tomography ([18F] FDG-PET/CT) in detection of pelvic and para-aortic nodal metastases in high-risk endometrial cancer. 20 patients with high-risk endometrial carcinoma underwent [18F] FDG-PET/CT followed by total abdominal hysterectomy, bilateral salpingo-oophorectomy and systematic pelvic lymphadenectomy with or without para-aortic lymphadenectomy. The findings on histopathology were compared with [18F] FDG-PET/CT findings to calculate the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of [18F] FDG-PET/CT. The pelvic nodal findings were analyzed on a patient and nodal chain based criteria. The para-aortic nodal findings were reported separately. Histopathology documented nodal involvement in two patients (10%). For detection of pelvic nodes, on a patient based analysis, [18F] FDG-PET/CT had a sensitivity of 100%, specificity of 61.11%, PPV of 22.22%, NPV of 100% and accuracy of 65% and on a nodal chain based analysis, [18F] FDG-PET/CT had a sensitivity of 100%, specificity of 80%, PPV of 20%, NPV of 100%, and accuracy of 80.95%. For detection of para-aortic nodes, [18F] FDG-PET/CT had sensitivity of 100%, specificity of 66.67%, PPV of 20%, NPV of 100%, and accuracy of 69.23%. Although [18F] FDG-PET/CT has high sensitivity for detection of LN metastasis in endometrial carcinoma, it had moderate accuracy and high false positivity. However, the high NPV is important in selecting patients in whom lymphadenectomy may be omitted. PMID:25538488

  6. Development of a phenotyping platform for high throughput screening of nodal root angle in sorghum.

    PubMed

    Joshi, Dinesh C; Singh, Vijaya; Hunt, Colleen; Mace, Emma; van Oosterom, Erik; Sulman, Richard; Jordan, David; Hammer, Graeme

    2017-01-01

    In sorghum, the growth angle of nodal roots is a major component of root system architecture. It strongly influences the spatial distribution of roots of mature plants in the soil profile, which can impact drought adaptation. However, selection for nodal root angle in sorghum breeding programs has been restricted by the absence of a suitable high throughput phenotyping platform. The aim of this study was to develop a phenotyping platform for the rapid, non-destructive and digital measurement of nodal root angle of sorghum at the seedling stage. The phenotyping platform comprises of 500 soil filled root chambers (50 × 45 × 0.3 cm in size), made of transparent perspex sheets that were placed in metal tubs and covered with polycarbonate sheets. Around 3 weeks after sowing, once the first flush of nodal roots was visible, roots were imaged in situ using an imaging box that included two digital cameras that were remotely controlled by two android tablets. Free software ( openGelPhoto.tcl ) allowed precise measurement of nodal root angle from the digital images. The reliability and efficiency of the platform was evaluated by screening a large nested association mapping population of sorghum and a set of hybrids in six independent experimental runs that included up to 500 plants each. The platform revealed extensive genetic variation and high heritability (repeatability) for nodal root angle. High genetic correlations and consistent ranking of genotypes across experimental runs confirmed the reproducibility of the platform. This low cost, high throughput root phenotyping platform requires no sophisticated equipment, is adaptable to most glasshouse environments and is well suited to dissect the genetic control of nodal root angle of sorghum. The platform is suitable for use in sorghum breeding programs aiming to improve drought adaptation through root system architecture manipulation.

  7. Evaluation of reliability modeling tools for advanced fault tolerant systems

    NASA Technical Reports Server (NTRS)

    Baker, Robert; Scheper, Charlotte

    1986-01-01

    The Computer Aided Reliability Estimation (CARE III) and Automated Reliability Interactice Estimation System (ARIES 82) reliability tools for application to advanced fault tolerance aerospace systems were evaluated. To determine reliability modeling requirements, the evaluation focused on the Draper Laboratories' Advanced Information Processing System (AIPS) architecture as an example architecture for fault tolerance aerospace systems. Advantages and limitations were identified for each reliability evaluation tool. The CARE III program was designed primarily for analyzing ultrareliable flight control systems. The ARIES 82 program's primary use was to support university research and teaching. Both CARE III and ARIES 82 were not suited for determining the reliability of complex nodal networks of the type used to interconnect processing sites in the AIPS architecture. It was concluded that ARIES was not suitable for modeling advanced fault tolerant systems. It was further concluded that subject to some limitations (the difficulty in modeling systems with unpowered spare modules, systems where equipment maintenance must be considered, systems where failure depends on the sequence in which faults occurred, and systems where multiple faults greater than a double near coincident faults must be considered), CARE III is best suited for evaluating the reliability of advanced tolerant systems for air transport.

  8. On Formulations of Discontinuous Galerkin and Related Methods for Conservation Laws

    NASA Technical Reports Server (NTRS)

    Huynh, H. T.

    2014-01-01

    A formulation for the discontinuous Galerkin (DG) method that leads to solutions using the differential form of the equation (as opposed to the standard integral form) is presented. The formulation includes (a) a derivative calculation that involves only data within each cell with no data interaction among cells, and (b) for each cell, corrections to this derivative that deal with the jumps in fluxes at the cell boundaries and allow data across cells to interact. The derivative with no interaction is obtained by a projection, but for nodal-type methods, evaluating this derivative by interpolation at the nodal points is more economical. The corrections are derived using the approximate (Dirac) delta functions. The formulation results in a family of schemes: different approximate delta functions give rise to different methods. It is shown that the current formulation is essentially equivalent to the flux reconstruction (FR) formulation. Due to the use of approximate delta functions, an energy stability proof simpler than that of Vincent, Castonguay, and Jameson (2011) for a family of schemes is derived. Accuracy and stability of resulting schemes are discussed via Fourier analyses. Similar to FR, the current formulation provides a unifying framework for high-order methods by recovering the DG, spectral difference (SD), and spectral volume (SV) schemes. It also yields stable, accurate, and economical methods.

  9. The Shock and Vibration Bulletin. Part 2. Invited Papers, Structural Dynamics

    DTIC Science & Technology

    1974-08-01

    VIKING LANDER DYNAMICS 41 Mr. Joseph C. Pohlen, Martin Marietta Aerospace, Denver, Colorado Structural Dynamics PERFORMANCE OF STATISTICAL ENERGY ANALYSIS 47...aerospace structures. Analytical prediction of these environments is beyond the current scope of classical modal techniques. Statistical energy analysis methods...have been developed that circumvent the difficulties of high-frequency nodal analysis. These statistical energy analysis methods are evaluated

  10. A nodal discontinuous Galerkin approach to 3-D viscoelastic wave propagation in complex geological media

    NASA Astrophysics Data System (ADS)

    Lambrecht, L.; Lamert, A.; Friederich, W.; Möller, T.; Boxberg, M. S.

    2018-03-01

    A nodal discontinuous Galerkin (NDG) approach is developed and implemented for the computation of viscoelastic wavefields in complex geological media. The NDG approach combines unstructured tetrahedral meshes with an element-wise, high-order spatial interpolation of the wavefield based on Lagrange polynomials. Numerical fluxes are computed from an exact solution of the heterogeneous Riemann problem. Our implementation offers capabilities for modelling viscoelastic wave propagation in 1-D, 2-D and 3-D settings of very different spatial scale with little logistical overhead. It allows the import of external tetrahedral meshes provided by independent meshing software and can be run in a parallel computing environment. Computation of adjoint wavefields and an interface for the computation of waveform sensitivity kernels are offered. The method is validated in 2-D and 3-D by comparison to analytical solutions and results from a spectral element method. The capabilities of the NDG method are demonstrated through a 3-D example case taken from tunnel seismics which considers high-frequency elastic wave propagation around a curved underground tunnel cutting through inclined and faulted sedimentary strata. The NDG method was coded into the open-source software package NEXD and is available from GitHub.

  11. Linear network representation of multistate models of transport.

    PubMed Central

    Sandblom, J; Ring, A; Eisenman, G

    1982-01-01

    By introducing external driving forces in rate-theory models of transport we show how the Eyring rate equations can be transformed into Ohm's law with potentials that obey Kirchhoff's second law. From such a formalism the state diagram of a multioccupancy multicomponent system can be directly converted into linear network with resistors connecting nodal (branch) points and with capacitances connecting each nodal point with a reference point. The external forces appear as emf or current generators in the network. This theory allows the algebraic methods of linear network theory to be used in solving the flux equations for multistate models and is particularly useful for making proper simplifying approximation in models of complex membrane structure. Some general properties of linear network representation are also deduced. It is shown, for instance, that Maxwell's reciprocity relationships of linear networks lead directly to Onsager's relationships in the near equilibrium region. Finally, as an example of the procedure, the equivalent circuit method is used to solve the equations for a few transport models. PMID:7093425

  12. EGFR immunoexpression, RAS immunoexpression and their effects on survival in lung adenocarcinoma cases

    PubMed Central

    Onder, Sevgen; Firat, Pinar; Dogan, Riza

    2014-01-01

    Background The impacts of epidermal growth factor receptor (EGFR) immunoexpression and RAS immunoexpression on the survival and prognosis of lung adenocarcinoma patients are debated in the literature. Methods Twenty-six patients, who underwent pulmonary resections between 2002 and 2007 in our clinic, and whose pathologic examinations yielded adenocarcinoma, were included in the study. EGFR and RAS expression levels were examined by immunohistochemical methods. The results were compared with the survival, stage of the disease, nodal involvement, lymphovascular invasion, and pleural invasion. Nonparametric bivariate analyses were used for statistical analyses. Results A significant link between EGFR immunoexpression and survival has been identified while RAS immunoexpression and survival have been proven to be irrelevant. Neither EGFR, nor RAS has displayed a significant link with the stage of the disease, nodal involvement, lymphovascular invasion, or pleural invasion. Conclusions Positive EGFR immunoexpression affects survival negatively, while RAS immunoexpression has no effect on survival in lung adenocarcinoma patients. PMID:24977003

  13. An Interesting Case of Retropharyngeal Lymph Nodal Metastases in a Case of Iodine-Refractory Thyroid Cancer.

    PubMed

    Harisankar, Chidambaram Natrajan Balasubramanian; Vijayabhaskar, Ramakrishnan

    2018-01-01

    Metastases to cervical lymph node are fairly common in differentiated thyroid cancer. In iodine-refractory disease, the disease may persist in the thyroid bed, cervical lymph nodes, lungs, or the bones commonly. Retropharyngeal lymph nodal involvement in thyroid cancer is unusual and may even be the presenting complaint. We represent a case of iodine-refractory thyroid cancer with retropharyngeal lymph nodal involvement in addition to lung metastases.

  14. EGF-CFC proteins are essential coreceptors for the TGF-β signals Vg1 and GDF1

    PubMed Central

    Cheng, Simon K.; Olale, Felix; Bennett, James T.; Brivanlou, Ali H.; Schier, Alexander F.

    2003-01-01

    The TGF-β signals Nodal, Activin, GDF1, and Vg1 have been implicated in mesoderm induction and left-right patterning. Nodal and Activin both activate Activin receptors, but only Nodal requires EGF-CFC coreceptors for signaling. We report that Vg1 and GDF1 signaling in zebrafish also depends on EGF-CFC proteins, but not on Nodal signals. Correspondingly, we find that in Xenopus Vg1 and GDF1 bind to and signal through Activin receptors only in the presence of EGF-CFC proteins. These results establish that multiple TGF-β signals converge on Activin receptor/EGF-CFC complexes and suggest a more widespread requirement for coreceptors in TGF-β signaling than anticipated previously. PMID:12514096

  15. MAGNETIC END CLOSURES FOR PLASMA CONFINING AND HEATING DEVICES

    DOEpatents

    Post, R.F.

    1963-08-20

    More effective magnetic closure field regions for various open-ended containment magnetic fields used in fusion reactor devices are provided by several spaced, coaxially-aligned solenoids utilized to produce a series of nodal field regions of uniform or, preferably, of incrementally increasing intensity separated by lower intensity regions outwardly from the ends of said containment zone. Plasma sources may also be provided to inject plasma into said lower intensity areas to increase plasma density therein. Plasma may then be transported, by plasma diffusion mechanisms provided by the nodal fields, into the containment field. With correlated plasma densities and nodal field spacings approximating the mean free partl cle collision path length in the zones between the nodal fields, optimum closure effectiveness is obtained. (AEC)

  16. Method and apparatus for routing data in an inter-nodal communications lattice of a massively parallel computer system by semi-randomly varying routing policies for different packets

    DOEpatents

    Archer, Charles Jens; Musselman, Roy Glenn; Peters, Amanda; Pinnow, Kurt Walter; Swartz, Brent Allen; Wallenfelt, Brian Paul

    2010-11-23

    A massively parallel computer system contains an inter-nodal communications network of node-to-node links. Nodes vary a choice of routing policy for routing data in the network in a semi-random manner, so that similarly situated packets are not always routed along the same path. Semi-random variation of the routing policy tends to avoid certain local hot spots of network activity, which might otherwise arise using more consistent routing determinations. Preferably, the originating node chooses a routing policy for a packet, and all intermediate nodes in the path route the packet according to that policy. Policies may be rotated on a round-robin basis, selected by generating a random number, or otherwise varied.

  17. Specialty functions singularity mechanics problems

    NASA Technical Reports Server (NTRS)

    Sarigul, Nesrin

    1989-01-01

    The focus is in the development of more accurate and efficient advanced methods for solution of singular problems encountered in mechanics. At present, finite element methods in conjunction with special functions, boolean sum and blending interpolations are being considered. In dealing with systems which contain a singularity, special finite elements are being formulated to be used in singular regions. Further, special transition elements are being formulated to couple the special element to the mesh that models the rest of the system, and to be used in conjunction with 1-D, 2-D and 3-D elements within the same mesh. Computational simulation with a least squares fit is being utilized to construct special elements, if there is an unknown singularity in the system. A novel approach is taken in formulation of the elements in that: (1) the material properties are modified to include time, temperature, coordinate and stress dependant behavior within the element; (2) material properties vary at nodal points of the elements; (3) a hidden-symbolic computation scheme is developed and utilized in formulating the elements; and (4) special functions and boolean sum are utilized in order to interpolate the field variables and their derivatives along the boundary of the elements. It may be noted that the proposed methods are also applicable to fluids and coupled problems.

  18. The Maternal Maverick/GDF15-like TGF-β Ligand Panda Directs Dorsal-Ventral Axis Formation by Restricting Nodal Expression in the Sea Urchin Embryo.

    PubMed

    Haillot, Emmanuel; Molina, Maria Dolores; Lapraz, François; Lepage, Thierry

    2015-01-01

    Specification of the dorsal-ventral axis in the highly regulative sea urchin embryo critically relies on the zygotic expression of nodal, but whether maternal factors provide the initial spatial cue to orient this axis is not known. Although redox gradients have been proposed to entrain the dorsal-ventral axis by acting upstream of nodal, manipulating the activity of redox gradients only has modest consequences, suggesting that other factors are responsible for orienting nodal expression and defining the dorsal-ventral axis. Here we uncover the function of Panda, a maternally provided transforming growth factor beta (TGF-β) ligand that requires the activin receptor-like kinases (Alk) Alk3/6 and Alk1/2 receptors to break the radial symmetry of the embryo and orient the dorsal-ventral axis by restricting nodal expression. We found that the double inhibition of the bone morphogenetic protein (BMP) type I receptors Alk3/6 and Alk1/2 causes a phenotype dramatically more severe than the BMP2/4 loss-of-function phenotype, leading to extreme ventralization of the embryo through massive ectopic expression of nodal, suggesting that an unidentified signal acting through BMP type I receptors cooperates with BMP2/4 to restrict nodal expression. We identified this ligand as the product of maternal Panda mRNA. Double inactivation of panda and bmp2/4 led to extreme ventralization, mimicking the phenotype caused by inactivation of the two BMP receptors. Inhibition of maternal panda mRNA translation disrupted the early spatial restriction of nodal, leading to persistent massive ectopic expression of nodal on the dorsal side despite the presence of Lefty. Phylogenetic analysis indicates that Panda is not a prototypical BMP ligand but a member of a subfamily of TGF-β distantly related to Inhibins, Lefty, and TGF-β that includes Maverick from Drosophila and GDF15 from vertebrates. Indeed, overexpression of Panda does not appear to directly or strongly activate phosphoSmad1/5/8 signaling, suggesting that although this TGF-β may require Alk1/2 and/or Alk3/6 to antagonize nodal expression, it may do so by sequestering a factor essential for Nodal signaling, by activating a non-Smad pathway downstream of the type I receptors, or by activating extremely low levels of pSmad1/5/8. We provide evidence that, although panda mRNA is broadly distributed in the early embryo, local expression of panda mRNA efficiently orients the dorsal-ventral axis and that Panda activity is required locally in the early embryo to specify this axis. Taken together, these findings demonstrate that maternal panda mRNA is both necessary and sufficient to orient the dorsal-ventral axis. These results therefore provide evidence that in the highly regulative sea urchin embryo, the activity of spatially restricted maternal factors regulates patterning along the dorsal-ventral axis.

  19. The Maternal Maverick/GDF15-like TGF-β Ligand Panda Directs Dorsal-Ventral Axis Formation by Restricting Nodal Expression in the Sea Urchin Embryo

    PubMed Central

    Haillot, Emmanuel; Molina, Maria Dolores; Lapraz, François; Lepage, Thierry

    2015-01-01

    Specification of the dorsal-ventral axis in the highly regulative sea urchin embryo critically relies on the zygotic expression of nodal, but whether maternal factors provide the initial spatial cue to orient this axis is not known. Although redox gradients have been proposed to entrain the dorsal-ventral axis by acting upstream of nodal, manipulating the activity of redox gradients only has modest consequences, suggesting that other factors are responsible for orienting nodal expression and defining the dorsal-ventral axis. Here we uncover the function of Panda, a maternally provided transforming growth factor beta (TGF-β) ligand that requires the activin receptor-like kinases (Alk) Alk3/6 and Alk1/2 receptors to break the radial symmetry of the embryo and orient the dorsal-ventral axis by restricting nodal expression. We found that the double inhibition of the bone morphogenetic protein (BMP) type I receptors Alk3/6 and Alk1/2 causes a phenotype dramatically more severe than the BMP2/4 loss-of-function phenotype, leading to extreme ventralization of the embryo through massive ectopic expression of nodal, suggesting that an unidentified signal acting through BMP type I receptors cooperates with BMP2/4 to restrict nodal expression. We identified this ligand as the product of maternal Panda mRNA. Double inactivation of panda and bmp2/4 led to extreme ventralization, mimicking the phenotype caused by inactivation of the two BMP receptors. Inhibition of maternal panda mRNA translation disrupted the early spatial restriction of nodal, leading to persistent massive ectopic expression of nodal on the dorsal side despite the presence of Lefty. Phylogenetic analysis indicates that Panda is not a prototypical BMP ligand but a member of a subfamily of TGF-β distantly related to Inhibins, Lefty, and TGF-β that includes Maverick from Drosophila and GDF15 from vertebrates. Indeed, overexpression of Panda does not appear to directly or strongly activate phosphoSmad1/5/8 signaling, suggesting that although this TGF-β may require Alk1/2 and/or Alk3/6 to antagonize nodal expression, it may do so by sequestering a factor essential for Nodal signaling, by activating a non-Smad pathway downstream of the type I receptors, or by activating extremely low levels of pSmad1/5/8. We provide evidence that, although panda mRNA is broadly distributed in the early embryo, local expression of panda mRNA efficiently orients the dorsal-ventral axis and that Panda activity is required locally in the early embryo to specify this axis. Taken together, these findings demonstrate that maternal panda mRNA is both necessary and sufficient to orient the dorsal-ventral axis. These results therefore provide evidence that in the highly regulative sea urchin embryo, the activity of spatially restricted maternal factors regulates patterning along the dorsal-ventral axis. PMID:26352141

  20. Anatomic Distribution of Fluorodeoxyglucose-Avid Para-aortic Lymph Nodes in Patients With Cervical Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Takiar, Vinita; Fontanilla, Hiral P.; Eifel, Patricia J.

    Purpose: Conformal treatment of para-aortic lymph nodes (PAN) in cervical cancer allows dose escalation and reduces normal tissue toxicity. Currently, data documenting the precise location of involved PAN are lacking. We define the spatial distribution of this high-risk nodal volume by analyzing fluorodeoxyglucose (FDG)-avid lymph nodes (LNs) on positron emission tomography/computed tomography (PET/CT) scans in patients with cervical cancer. Methods and Materials: We identified 72 PANs on pretreatment PET/CT of 30 patients with newly diagnosed stage IB-IVA cervical cancer treated with definitive chemoradiation. LNs were classified as left-lateral para-aortic (LPA), aortocaval (AC), or right paracaval (RPC). Distances from the LNmore » center to the closest vessel and adjacent vertebral body were calculated. Using deformable image registration, nodes were mapped to a template computed tomogram to provide a visual impression of nodal frequencies and anatomic distribution. Results: We identified 72 PET-positive para-aortic lymph nodes (37 LPA, 32 AC, 3 RPC). All RPC lymph nodes were in the inferior third of the para-aortic region. The mean distance from aorta for all lymph nodes was 8.3 mm (range, 3-17 mm), and from the inferior vena cava was 5.6 mm (range, 2-10 mm). Of the 72 lymph nodes, 60% were in the inferior third, 36% were in the middle third, and 4% were in the upper third of the para-aortic region. In all, 29 of 30 patients also had FDG-avid pelvic lymph nodes. Conclusions: A total of 96% of PET positive nodes were adjacent to the aorta; PET positive nodes to the right of the IVC were rare and were all located distally, within 3 cm of the aortic bifurcation. Our findings suggest that circumferential margins around the vessels do not accurately define the nodal region at risk. Instead, the anatomical extent of the nodal basin should be contoured on each axial image to provide optimal coverage of the para-aortic nodal compartment.« less

  1. Outcomes in a Multi-institutional Cohort of Patients Treated With Intraoperative Radiation Therapy for Advanced or Recurrent Renal Cell Carcinoma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Paly, Jonathan J.; Hallemeier, Christopher L.; Biggs, Peter J.

    2014-03-01

    Purpose/Objective(s): This study aimed to analyze outcomes in a multi-institutional cohort of patients with advanced or recurrent renal cell carcinoma (RCC) who were treated with intraoperative radiation therapy (IORT). Methods and Materials: Between 1985 and 2010, 98 patients received IORT for advanced or locally recurrent RCC at 9 institutions. The median follow-up time for surviving patients was 3.5 years. Overall survival (OS), disease-specific survival (DSS), and disease-free survival (DFS) were estimated with the Kaplan-Meier method. Chained imputation accounted for missing data, and multivariate Cox hazards regression tested significance. Results: IORT was delivered during nephrectomy for advanced disease (28%) or duringmore » resection of locally recurrent RCC in the renal fossa (72%). Sixty-nine percent of the patients were male, and the median age was 58 years. At the time of primary resection, the T stages were as follows: 17% T1, 12% T2, 55% T3, and 16% T4. Eighty-seven percent of the patients had a visibly complete resection of tumor. Preoperative or postoperative external beam radiation therapy was administered to 27% and 35% of patients, respectively. The 5-year OS was 37% for advanced disease and 55% for locally recurrent disease. The respective 5-year DSS was 41% and 60%. The respective 5-year DFS was 39% and 52%. Initial nodal involvement (hazard ratio [HR] 2.9-3.6, P<.01), presence of sarcomatoid features (HR 3.7-6.9, P<.05), and higher IORT dose (HR 1.3, P<.001) were statistically significantly associated with decreased survival. Adjuvant systemic therapy was associated with decreased DSS (HR 2.4, P=.03). For locally recurrent tumors, positive margin status (HR 2.6, P=.01) was associated with decreased OS. Conclusions: We report the largest known cohort of patients with RCC managed by IORT and have identified several factors associated with survival. The outcomes for patients receiving IORT in the setting of local recurrence compare favorably to similar cohorts treated by local resection alone suggesting the potential for improved DFS with IORT.« less

  2. Dynamic Contrast-Enhanced Magnetic Resonance Imaging as a Predictor of Outcome in Head-and-Neck Squamous Cell Carcinoma Patients With Nodal Metastases

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shukla-Dave, Amita, E-mail: davea@mskcc.org; Department of Radiology, Memorial Sloan-Kettering Cancer Center, New York, NY; Lee, Nancy Y.

    2012-04-01

    Purpose: Dynamic contrast-enhanced MRI (DCE-MRI) can provide information regarding tumor perfusion and permeability and has shown prognostic value in certain tumors types. The goal of this study was to assess the prognostic value of pretreatment DCE-MRI in head and neck squamous cell carcinoma (HNSCC) patients with nodal disease undergoing chemoradiation therapy or surgery. Methods and Materials: Seventy-four patients with histologically proven squamous cell carcinoma and neck nodal metastases were eligible for the study. Pretreatment DCE-MRI was performed on a 1.5T MRI. Clinical follow-up was a minimum of 12 months. DCE-MRI data were analyzed using the Tofts model. DCE-MRI parameters weremore » related to treatment outcome (progression-free survival [PFS] and overall survival [OS]). Patients were grouped as no evidence of disease (NED), alive with disease (AWD), dead with disease (DOD), or dead of other causes (DOC). Prognostic significance was assessed using the log-rank test for single variables and Cox proportional hazards regression for combinations of variables. Results: At last clinical follow-up, for Stage III, all 12 patients were NED. For Stage IV, 43 patients were NED, 4 were AWD, 11 were DOD, and 4 were DOC. K{sup trans} is volume transfer constant. In a stepwise Cox regression, skewness of K{sup trans} (volume transfer constant) was the strongest predictor for Stage IV patients (PFS and OS: p <0.001). Conclusion: Our study shows that skewness of K{sup trans} was the strongest predictor of PFS and OS in Stage IV HNSCC patients with nodal disease. This study suggests an important role for pretreatment DCE-MRI parameter K{sup trans} as a predictor of outcome in these patients.« less

  3. Correlation between the sudden jump-like increases of the atrio-Hisian interval induced during burst atrial pacing and during programmed atrial stimulation in patients with atrioventricular nodal reentrant tachycardia.

    PubMed

    Bayraktarova, Iskra H; Stoyanov, Milko K; Kunev, Boyan T; Shalganov, Tchavdar N

    To study the correlation between the sudden prolongations of the atrio-Hisian (AH) interval with ≥50 ms during burst and programmed atrial stimulation, and to define whether the AH jump during burst atrial pacing is a reliable diagnostic criterion for dual AV nodal physiology. Retrospective data on 304 patients with preliminary ECG diagnosis of AV nodal reentrant tachycardia (AVNRT), confirmed during electrophysiological study, was analyzed for the presence of AH jump during burst and programmed atrial stimulation, and for correlation between the pacing modes for inducing the jump. Wilcoxon signed-ranks test and Spearman's bivariate correlation coefficient were applied, significant was P-value <0.05. The population was aged 48.5 ± 15.7 (12-85) years; males were 38.5%. AH jump occurred during burst atrial pacing in 81% of the patients, and during programmed stimulation - in 78%, P = 0.366. In 63.2% AH jump was induced by both pacing modes; in 17.8% - only by burst pacing; in 14.8% - only by programmed pacing; in 4.2% there was no inducible jump. There was negative correlation between both pacing modes, ρ = -0.204, Р<0.001. Burst and programmed atrial stimulation separately prove the presence of dual AV nodal physiology in 81 and 78% of the patients with AVNRT, respectively. There is negative correlation between the two pacing modes, allowing the combination of the two methods to prove diagnostic in 95.8% of the patients. Copyright © 2017 Indian Heart Rhythm Society. Production and hosting by Elsevier B.V. All rights reserved.

  4. Sensitive molecular detection of small nodal metastasis in uterine cervical cancer using HPV16-E6/CK19/MUC1 cancer biomarkers.

    PubMed

    Samouëlian, Vanessa; Mechtouf, Nawel; Leblanc, Eric; Cardin, Guillaume B; Lhotellier, Valérie; Querleu, Denis; Révillion, Françoise; Rodier, Francis

    2018-04-24

    Metastatic nodal involvement is a critical prognostic factor in uterine cervical cancer (UCC). To improve current methods of detecting UCC metastases in lymph nodes (LNs), we used quantitative PCR (qPCR) to assess mRNA expression of potential metastatic biomarkers. We found that expression of HPV16-E6, cytokeratin19 (CK19), and mucin1 (MUC1) is consistently upregulated in tumors and metastatic tissues, supporting a role for these genes in UCC progression. These putative biomarkers were able to predict the presence of histologically positive metastatic LNs with respective sensitivities and specificities of 82% and 99% (CK19), 76% and 95% (HPV16-E6), and 76% and 78% (MUC1). While the biomarkers failed to detect 1.7% to 2.2% of the histologically positive LNs when used individually, combining CK19 and HPV16-E6 enhanced sensitivity and specificity to 100% and 94%, respectively. To explore the sensitivity of qPCR-based detection of varying proportions of invading HPV16-positive UCC cells, we designed a LN metastasis model that achieved a fresh cell detection limit of 0.008% (1:12500 HPV16-positive to HPV16-negative cells), and a paraffin-embedded, formalin-fixed (PEFF) detection limit of 0.02% (1:5000 HPV16-positive to HPV16-negative cells), both of which are within the theoretical detection limit for micrometastasis. Thus, HPV E6/E7 oncogenes may be useful targets for the ultrasensitive detection of nodal involvements like micrometastases in fresh or archived tissue samples. Moreover, our results suggest that the biomarker combination of CK19/HPV-E6 could support a real-time intraoperative strategy for the detection of small, but potentially lethal, metastatic nodal involvements in fresh UCC tissues.

  5. A Prognostic Index for Predicting Lymph Node Metastasis in Minor Salivary Gland Cancer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lloyd, Shane; Yu, James B.; Ross, Douglas A.

    2010-01-15

    Purpose: Large studies examining the clinical and pathological factors associated with nodal metastasis in minor salivary gland cancer are lacking in the literature. Methods and Materials: Using the Surveillance, Epidemiology, and End Results (SEER) database, we identified 2,667 minor salivary gland cancers with known lymph node status from 1988 to 2004. Univariate and multivariate analyses were conducted to identify factors associated with the use of neck dissection, the use of external beam radiation therapy, and the presence of cervical lymph node metastases. Results: Four hundred twenty-six (16.0%) patients had neck nodal involvement. Factors associated with neck nodal involvement on univariatemore » analysis included increasing age, male sex, increasing tumor size, high tumor grade, T3-T4 stage, adenocarcinoma or mucoepidermoid carcinomas, and pharyngeal site of primary malignancy. On multivariate analysis, four statistically significant factors were identified, including male sex, T3-T4 stage, pharyngeal site of primary malignancy, and high-grade adenocarcinoma or high-grade mucoepidermoid carcinomas. The proportions (and 95% confidence intervals) of patients with lymph node involvement for those with 0, 1, 2, 3, and 4 of these prognostic factors were 0.02 (0.01-0.03), 0.09 (0.07-0.11), 0.17 (0.14-0.21), 0.41 (0.33-0.49), and 0.70 (0.54-0.85), respectively. Grade was a significant predictor of metastasis for adenocarcinoma and mucoepidermoid carcinoma but not for adenoid cystic carcinoma. Conclusions: A prognostic index using the four clinicopathological factors listed here can effectively differentiate patients into risk groups of nodal metastasis. The precision of this index is subject to the limitations of SEER data and should be validated in further clinical studies.« less

  6. Intensive field phenotyping of maize (Zea mays L.) root crowns identifies phenes and phene integration associated with plant growth and nitrogen acquisition.

    PubMed

    York, Larry M; Lynch, Jonathan P

    2015-09-01

    Root architecture is an important regulator of nitrogen (N) acquisition. Existing methods to phenotype the root architecture of cereal crops are generally limited to seedlings or to the outer roots of mature root crowns. The functional integration of root phenes is poorly understood. In this study, intensive phenotyping of mature root crowns of maize was conducted to discover phenes and phene modules related to N acquisition. Twelve maize genotypes were grown under replete and deficient N regimes in the field in South Africa and eight in the USA. An image was captured for every whorl of nodal roots in each crown. Custom software was used to measure root phenes including nodal occupancy, angle, diameter, distance to branching, lateral branching, and lateral length. Variation existed for all root phenes within maize root crowns. Size-related phenes such as diameter and number were substantially influenced by nodal position, while angle, lateral density, and distance to branching were not. Greater distance to branching, the length from the shoot to the emergence of laterals, is proposed to be a novel phene state that minimizes placing roots in already explored soil. Root phenes from both older and younger whorls of nodal roots contributed to variation in shoot mass and N uptake. The additive integration of root phenes accounted for 70% of the variation observed in shoot mass in low N soil. These results demonstrate the utility of intensive phenotyping of mature root systems, as well as the importance of phene integration in soil resource acquisition. © The Author 2015. Published by Oxford University Press on behalf of the Society for Experimental Biology.

  7. Robust doubly charged nodal lines and nodal surfaces in centrosymmetric systems

    NASA Astrophysics Data System (ADS)

    Bzdušek, Tomáš; Sigrist, Manfred

    2017-10-01

    Weyl points in three spatial dimensions are characterized by a Z -valued charge—the Chern number—which makes them stable against a wide range of perturbations. A set of Weyl points can mutually annihilate only if their net charge vanishes, a property we refer to as robustness. While nodal loops are usually not robust in this sense, it has recently been shown using homotopy arguments that in the centrosymmetric extension of the AI symmetry class they nevertheless develop a Z2 charge analogous to the Chern number. Nodal loops carrying a nontrivial value of this Z2 charge are robust, i.e., they can be gapped out only by a pairwise annihilation and not on their own. As this is an additional charge independent of the Berry π -phase flowing along the band degeneracy, such nodal loops are, in fact, doubly charged. In this manuscript, we generalize the homotopy discussion to the centrosymmetric extensions of all Atland-Zirnbauer classes. We develop a tailored mathematical framework dubbed the AZ +I classification and show that in three spatial dimensions such robust and multiply charged nodes appear in four of such centrosymmetric extensions, namely, AZ +I classes CI and AI lead to doubly charged nodal lines, while D and BDI support doubly charged nodal surfaces. We remark that no further crystalline symmetries apart from the spatial inversion are necessary for their stability. We provide a description of the corresponding topological charges, and develop simple tight-binding models of various semimetallic and superconducting phases that exhibit these nodes. We also indicate how the concept of robust and multiply charged nodes generalizes to other spatial dimensions.

  8. A predictive index of axillary nodal involvement in operable breast cancer.

    PubMed Central

    De Laurentiis, M.; Gallo, C.; De Placido, S.; Perrone, F.; Pettinato, G.; Petrella, G.; Carlomagno, C.; Panico, L.; Delrio, P.; Bianco, A. R.

    1996-01-01

    We investigated the association between pathological characteristics of primary breast cancer and degree of axillary nodal involvement and obtained a predictive index of the latter from the former. In 2076 cases, 17 histological features, including primary tumour and local invasion variables, were recorded. The whole sample was randomly split in a training (75% of cases) and a test sample. Simple and multiple correspondence analysis were used to select the variables to enter in a multinomial logit model to build an index predictive of the degree of nodal involvement. The response variable was axillary nodal status coded in four classes (N0, N1-3, N4-9, N > or = 10). The predictive index was then evaluated by testing goodness-of-fit and classification accuracy. Covariates significantly associated with nodal status were tumour size (P < 0.0001), tumour type (P < 0.0001), type of border (P = 0.048), multicentricity (P = 0.003), invasion of lymphatic and blood vessels (P < 0.0001) and nipple invasion (P = 0.006). Goodness-of-fit was validated by high concordance between observed and expected number of cases in each decile of predicted probability in both training and test samples. Classification accuracy analysis showed that true node-positive cases were well recognised (84.5%), but there was no clear distinction among the classes of node-positive cases. However, 10 year survival analysis showed a superimposible prognostic behaviour between predicted and observed nodal classes. Moreover, misclassified node-negative patients (i.e. those who are predicted positive) showed an outcome closer to patients with 1-3 metastatic nodes than to node-negative ones. In conclusion, the index cannot completely substitute for axillary node information, but it is a predictor of prognosis as accurate as nodal involvement and identifies a subgroup of node-negative patients with unfavourable prognosis. PMID:8630286

  9. Developmental changes in electrophysiological characteristics of human-induced pluripotent stem cell-derived cardiomyocytes.

    PubMed

    Ben-Ari, Meital; Naor, Shulamit; Zeevi-Levin, Naama; Schick, Revital; Ben Jehuda, Ronen; Reiter, Irina; Raveh, Amit; Grijnevitch, Inna; Barak, Omri; Rosen, Michael R; Weissman, Amir; Binah, Ofer

    2016-12-01

    Previous studies proposed that throughout differentiation of human induced Pluripotent Stem Cell-derived cardiomyocytes (iPSC-CMs), only 3 types of action potentials (APs) exist: nodal-, atrial-, and ventricular-like. To investigate whether there are precisely 3 phenotypes or a continuum exists among them, we tested 2 hypotheses: (1) During culture development a cardiac precursor cell is present that-depending on age-can evolve into the 3 phenotypes. (2) The predominant pattern is early prevalence of a nodal phenotype, transient appearance of an atrial phenotype, evolution to a ventricular phenotype, and persistence of transitional phenotypes. To test these hypotheses, we (1) performed fluorescence-activated cell sorting analysis of nodal, atrial, and ventricular markers; (2) recorded APs from 280 7- to 95-day-old iPSC-CMs; and (3) analyzed AP characteristics. The major findings were as follows: (1) fluorescence-activated cell sorting analysis of 30- and 60-day-old cultures showed that an iPSC-CMs population shifts from the nodal to the atrial/ventricular phenotype while including significant transitional populations; (2) the AP population did not consist of 3 phenotypes; (3) culture aging was associated with a shift from nodal to ventricular dominance, with a transient (57-70 days) appearance of the atrial phenotype; and (4) beat rate variability was more prominent in nodal than in ventricular cardiomyocytes, while pacemaker current density increased in older cultures. From the onset of development in culture, the iPSC-CMs population includes nodal, atrial, and ventricular APs and a broad spectrum of transitional phenotypes. The most readily distinguishable phenotype is atrial, which appears only transiently yet dominates at 57-70 days of evolution. Copyright © 2016 Heart Rhythm Society. Published by Elsevier Inc. All rights reserved.

  10. Multi-directional fault detection system

    DOEpatents

    Archer, Charles Jens; Pinnow, Kurt Walter; Ratterman, Joseph D.; Smith, Brian Edward

    2010-11-23

    An apparatus, program product and method checks for nodal faults in a group of nodes comprising a center node and all adjacent nodes. The center node concurrently communicates with the immediately adjacent nodes in three dimensions. The communications are analyzed to determine a presence of a faulty node or connection.

  11. Multi-directional fault detection system

    DOEpatents

    Archer, Charles Jens [Rochester, MN; Pinnow, Kurt Walter [Rochester, MN; Ratterman, Joseph D [Rochester, MN; Smith, Brian Edward [Rochester, MN

    2009-03-17

    An apparatus, program product and method checks for nodal faults in a group of nodes comprising a center node and all adjacent nodes. The center node concurrently communicates with the immediately adjacent nodes in three dimensions. The communications are analyzed to determine a presence of a faulty node or connection.

  12. State-Space Formulation for Circuit Analysis

    ERIC Educational Resources Information Center

    Martinez-Marin, T.

    2010-01-01

    This paper presents a new state-space approach for temporal analysis of electrical circuits. The method systematically obtains the state-space formulation of nondegenerate linear networks without using concepts of topology. It employs nodal/mesh systematic analysis to reduce the number of undesired variables. This approach helps students to…

  13. Multi-directional fault detection system

    DOEpatents

    Archer, Charles Jens; Pinnow, Kurt Walter; Ratterman, Joseph D.; Smith, Brian Edward

    2010-06-29

    An apparatus, program product and method checks for nodal faults in a group of nodes comprising a center node and all adjacent nodes. The center node concurrently communicates with the immediately adjacent nodes in three dimensions. The communications are analyzed to determine a presence of a faulty node or connection.

  14. Nodal network generator for CAVE3

    NASA Technical Reports Server (NTRS)

    Palmieri, J. V.; Rathjen, K. A.

    1982-01-01

    A new extension of CAVE3 code was developed that automates the creation of a finite difference math model in digital form ready for input to the CAVE3 code. The new software, Nodal Network Generator, is broken into two segments. One segment generates the model geometry using a Tektronix Tablet Digitizer and the other generates the actual finite difference model and allows for graphic verification using Tektronix 4014 Graphic Scope. Use of the Nodal Network Generator is described.

  15. Counting nodal domains on surfaces of revolution

    NASA Astrophysics Data System (ADS)

    Karageorge, Panos D.; Smilansky, Uzy

    2008-05-01

    We consider eigenfunctions of the Laplace-Beltrami operator on special surfaces of revolution. For this separable system, the nodal domains of the (real) eigenfunctions form a checkerboard pattern, and their number νn is proportional to the product of the angular and the 'surface' quantum numbers. Arranging the wavefunctions by increasing values of the Laplace-Beltrami spectrum, we obtain the nodal sequence, whose statistical properties we study. In particular, we investigate the distribution of the normalized counts \\frac{\

  16. Implications of inaccurate clinical nodal staging in pancreatic adenocarcinoma.

    PubMed

    Swords, Douglas S; Firpo, Matthew A; Johnson, Kirsten M; Boucher, Kenneth M; Scaife, Courtney L; Mulvihill, Sean J

    2017-07-01

    Many patients with stage I-II pancreatic adenocarcinoma do not undergo resection. We hypothesized that (1) clinical staging underestimates nodal involvement, causing stage IIB to have a greater percent of resected patients and (2) this stage-shift causes discrepancies in observed survival. The Surveillance, Epidemiology, and End Results (SEER) research database was used to evaluate cause-specific survival in patients with pancreatic adenocarcinoma from 2004-2012. Survival was compared using the log-rank test. Single-center data on 105 patients who underwent resection of pancreatic adenocarcinoma without neoadjuvant treatment were used to compare clinical and pathologic nodal staging. In SEER data, medium-term survival in stage IIB was superior to IB and IIA, with median cause-specific survival of 14, 9, and 11 months, respectively (P < .001). Seventy-two percent of stage IIB patients underwent resection vs 28% in IB and 36% in IIA (P < .001). In our institutional data, 12.4% of patients had clinical evidence of nodal involvement vs 69.5% by pathologic staging (P < .001). Among clinical stage IA-IIA patients, 71.6% had nodal involvement by pathologic staging. Both SEER and institutional data support substantial underestimation of nodal involvement by clinical staging. This finding has implications in decisions regarding neoadjuvant therapy and analysis of outcomes in the absence of pathologic staging. Copyright © 2017 Elsevier Inc. All rights reserved.

  17. Quality assessment of lymph node sampling in rhabdomyosarcoma: A surveillance, epidemiology, and end results (SEER) program study.

    PubMed

    Lobeck, Inna; Dupree, Phylicia; Karns, Rebekah; Rodeberg, David; von Allmen, Daniel; Dasgupta, Roshni

    2017-04-01

    Lymph node sampling is integral in the management of extremity and paratesticular rhabdomyosarcoma (RMS). The aim of this study was to determine overall surgical compliance with treatment protocols and impact of nodal sampling outcomes in these tumors. A query of the surveillance, epidemiology, and end results program (SEER) database was performed from 2003 to 2008 for patients <19years of age with RMS. Data obtained included demographics, five-year survival and rate of nodal sampling. Analysis was performed utilizing chi-squared, Kaplan-Meier and hazard ratio modeling. Of 537 patients with extremity RMS, nodal sampling was performed in 25.7% (n=138). This lack of nodal sampling had a negative outcome on survival (p=0.004). Sixty five patients with paratesticular RMS aged greater than 10 were identified and also displayed low rates of lymph node sampling (47.7%, n=31). For paratesticular patients, a similar increase in survival was seen in patients who underwent nodal evaluation (p=0.024). Lymph node sampling is the standard of care in RMS. However, surgical compliance with treatment protocols is poor. Nodal evaluation correlated significantly with overall survival. These findings suggest a need for improved education among surgeons and oncologists regarding the need lymph node assessment in pediatric oncology patients. Evidence rating/classification: Prognosis study, Level III. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Encapsulation of nodal cuttings and shoot tips for storage and exchange of cassava germplasm.

    PubMed

    Danso, K E; Ford-Lloyd, B V

    2003-04-01

    We report the encapsulation of in vitro-derived nodal cuttings or shoot tips of cassava in 3% calcium alginate for storage and germplasm exchange purposes. Shoot regrowth was not significantly affected by the concentration of sucrose in the alginate matrix while root formation was. In contrast, increasing the sucrose concentration in the calcium chloride polymerisation medium significantly reduced regrowth from encapsulated nodal cuttings of accession TME 60444. Supplementing the alginate matrix with increased concentrations of 6-benzylaminopurine and alpha-naphthaleneacetic acid enhanced complete plant regrowth within 2 weeks. Furthermore, plant regrowth by encapsulated nodal cuttings and shoot tips was significantly affected by the duration of the storage period as shoot recovery decreased from almost 100% to 73.3% for encapsulated nodal cuttings and 94.4% to 60% for shoot tips after 28 days of storage. The high frequency of plant regrowth from alginate-coated micropropagules coupled with high viability percentage after 28 days of storage is highly encouraging for the exchange of cassava genetic resources. Such encapsulated micropropagules could be used as an alternative to synthetic seeds derived from somatic embryos.

  19. Extended field intensity modulated radiation therapy with concomitant boost for lymph node-positive cervical cancer: analysis of regional control and recurrence patterns in the positron emission tomography/computed tomography era.

    PubMed

    Vargo, John A; Kim, Hayeon; Choi, Serah; Sukumvanich, Paniti; Olawaiye, Alexander B; Kelley, Joseph L; Edwards, Robert P; Comerci, John T; Beriwal, Sushil

    2014-12-01

    Positron emission tomography/computed tomography (PET/CT) is commonly used for nodal staging in locally advanced cervical cancer; however the false negative rate for para-aortic disease are 20% to 25% in PET-positive pelvic nodal disease. Unless surgically staged, pelvis-only treatment may undertreat para-aortic disease. We have treated patients with PET-positive nodes with extended field intensity modulated radiation therapy (IMRT) to address the para-aortic region prophylactically with concomitant boost to involved nodes. The purpose of this study was to assess regional control rates and recurrence patterns. Sixty-one patients with cervical cancer (stage IBI-IVA) diagnosed from 2003 to 2012 with PET-avid pelvic nodes treated with extended field IMRT (45 Gy in 25 fractions with concomitant boost to involved nodes to a median of 55 Gy in 25 fractions) with concurrent cisplatin and brachytherapy were retrospectively analyzed. The nodal location was pelvis-only in 41 patients (67%) and pelvis + para-aortic in 20 patients (33%). There were a total of 179 nodes, with a median number of positive nodes of 2 (range, 1-16 nodes) per patient and a median nodal size of 1.8 cm (range, 0.7-4.5 cm). Response was assessed by PET/CT at 12 to 16 weeks. Complete clinical and imaging response at the first follow-up visit was seen in 77% of patients. At a mean follow-up time of 29 months (range, 3-116 months), 8 patients experienced recurrence. The sites of persistent/recurrent disease were as follows: cervix 10 (16.3%), regional nodes 3 (4.9%), and distant 14 (23%). The rate of para-aortic failure in patients with pelvic-only nodes was 2.5%. There were no significant differences in recurrence patterns by the number/location of nodes, largest node size, or maximum node standardized uptake value. The rate of late grade 3+ adverse events was 4%. Extended field IMRT was well tolerated and resulted in low regional recurrence in node-positive cervical cancer. The dose of 55 Gy in 25 fractions was effective in eradicating disease in involved nodes, with acceptable late adverse events. Distant metastasis is the predominant mode of failure, and the OUTBACK trial may challenge the presented paradigms. Copyright © 2014 Elsevier Inc. All rights reserved.

  20. Indications for Pelvic Nodal Treatment in Prostate Cancer Should Change. Validation of the Roach Formula in a Large Extended Nodal Dissection Series

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Abdollah, Firas; Cozzarini, Cesare; Suardi, Nazareno

    2012-06-01

    Purpose: Previous studies have criticized the predicting ability of the Roach formula in assessing the risk of lymph node invasion (LNI) in contemporary patients with prostate cancer (PCa) due to a significant overestimation of LNI rates. However, all those studies included patients treated with limited pelvic lymph node dissection (PLND), which is associated with high rates of false negative findings. We hypothesized that the Roach formula is still an accurate tool for LNI predictions if an extended PLND (ePLND) is performed. Methods and Materials: We included 3,115 consecutive patients treated with radical prostatectomy and ePLND between 2000 and 2010 atmore » a single tertiary referral center. Extended PLND consisted of removal of obturator, external iliac, and hypogastric lymph nodes. We externally validated the Roach formula by using the area under the receiver operating characteristics curve and calibration plot method. Moreover, we tested the performance characteristics of different formula-generated cutoff values ranging from 1% to 20%. Results: The accuracy of the Roach formula was 80.3%. The calibration showed only a minor underestimation of the LNI risk in high-risk patients (6.7%). According to the Roach formula, the use of 15% cut off would have allowed 74.2% (2,311/3,115) of patients to avoid nodal irradiation, while up to 32.7% (111/336) of all patients with LNI would have been missed. When the cut off was lowered to 6%, nodal treatment would have been spared in 1,541 (49.5%) patients while missing 41 LNI patients. The sensitivity, specificity, and negative predictive values associated with the 6% cut off were 87.9%, 54%, and 97.3%, respectively. Conclusions: The Roach formula is still accurate and does not overestimate the rate of LNI in contemporary prostate cancer patients if they are treated with ePLND. However, the recommended cut off of 15% would miss approximately one-third of patients with LNI. Based on our results, the cut off should be lowered to 6%.« less

  1. The Adverse Survival Implications of Bland Thrombus in Renal Cell Carcinoma With Venous Tumor Thrombus.

    PubMed

    Hutchinson, Ryan; Rew, Charles; Chen, Gong; Woldu, Solomon; Krabbe, Laura-Maria; Meissner, Matthew; Sheth, Kunj; Singla, Nirmish; Shakir, Nabeel; Master, Viraj A; Karam, Jose A; Matin, Surena F; Borregales, Leonardo D; Wood, Christopher; Masterson, Timothy; Thompson, R Houston; Boorjian, Stephen A; Leibovich, Bradley C; Abel, E Jason; Bagrodia, Aditya; Margulis, Vitaly

    2018-05-01

    To characterize the presence of bland (nontumor) thrombus in advanced renal cell carcinoma and assess the impact of this finding on cancer-specific survival. A multi-institutional database of patients treated with nephrectomy with caval thrombectomy for locally-advanced renal tumors was assembled from 5 tertiary care medical centers. Using clinicopathologic variables including patient age, body mass index, Eastern Cooperative Oncology Group performance status, tumor stage, grade, nodal status and histology, and nearest-neighbor and multiple-matching propensity score matched cohorts of bland thrombus vs nonbland thrombus patients were assessed. Multivariable analysis for predictors of cancer-specific survival was performed. From an initial cohort of 579 patients, 446 met inclusion criteria (174 with bland thrombus, 272 without). At baseline, patients with bland thrombus had significantly worse performance status, higher tumor stage, higher prevalence of regional nodal metastases and higher nuclear grade (P < .01 for all). In both nearest-neighbor and multiple-matching propensity score matched cohorts, the presence of bland thrombus presence was associated with inferior median cancer-specific survival (28.1 months vs 156.8 months, and 28.1 months vs 76.7 months, P < .001 for both). The presence of bland thrombus remained independently associated with an increased risk of cancer-specific mortality on multivariable analysis (hazard ratio 4.33, 95% confidence interval 2.79-6.73, P < .001). Presence of bland thrombus is associated with adverse survival outcomes in patients treated surgically for renal tumors with venous tumor thrombus. These findings may have important implications in patient counseling, selection for surgery and inclusion in clinical trials. Copyright © 2018 Elsevier Inc. All rights reserved.

  2. RW Per - Nodal motion changes its amplitude by 1.4 mag

    NASA Technical Reports Server (NTRS)

    Schaefer, Bradley E.; Fried, Robert E.

    1991-01-01

    RW Per was found to have large secular changes in its eclipse amplitude. In blue light, for example, the amplitude was 3.2 mag in the early 1900s, 2.2 mag in the late 1960s, and 1.75 mag in 1990. Throughout this time, the brightness at maximum was constant in all colors. It is shown that the only possible explanation is nodal motion, where the inclination varies with a period of roughly 100,000 yr. The nodal motion is caused by a third star, for which the light curve, the colors, and the O - C curve already provide evidence. Thus, RW Per is only the fourth known star with large changes of eclipse amplitude and is only the second example of nodal motion.

  3. Functional Connectivity Changes in Resting-State EEG as Potential Biomarker for Amyotrophic Lateral Sclerosis

    PubMed Central

    Iyer, Parameswaran Mahadeva; Egan, Catriona; Pinto-Grau, Marta; Burke, Tom; Elamin, Marwa; Nasseroleslami, Bahman; Pender, Niall; Lalor, Edmund C.; Hardiman, Orla

    2015-01-01

    Background Amyotrophic Lateral Sclerosis (ALS) is heterogeneous and overlaps with frontotemporal dementia. Spectral EEG can predict damage in structural and functional networks in frontotemporal dementia but has never been applied to ALS. Methods 18 incident ALS patients with normal cognition and 17 age matched controls underwent 128 channel EEG and neuropsychology assessment. The EEG data was analyzed using FieldTrip software in MATLAB to calculate simple connectivity measures and scalp network measures. sLORETA was used in nodal analysis for source localization and same methods were applied as above to calculate nodal network measures. Graph theory measures were used to assess network integrity. Results Cross spectral density in alpha band was higher in patients. In ALS patients, increased degree values of the network nodes was noted in the central and frontal regions in the theta band across seven of the different connectivity maps (p<0.0005). Among patients, clustering coefficient in alpha and gamma bands was increased in all regions of the scalp and connectivity were significantly increased (p=0.02). Nodal network showed increased assortativity in alpha band in the patients group. The Clustering Coefficient in Partial Directed Connectivity (PDC) showed significantly higher values for patients in alpha, beta, gamma, theta and delta frequencies (p=0.05). Discussion There is increased connectivity in the fronto-central regions of the scalp and areas corresponding to Salience and Default Mode network in ALS, suggesting a pathologic disruption of neuronal networking in early disease states. Spectral EEG has potential utility as a biomarker in ALS. PMID:26091258

  4. Multi-threshold white matter structural networks fusion for accurate diagnosis of Tourette syndrome children

    NASA Astrophysics Data System (ADS)

    Wen, Hongwei; Liu, Yue; Wang, Shengpei; Li, Zuoyong; Zhang, Jishui; Peng, Yun; He, Huiguang

    2017-03-01

    Tourette syndrome (TS) is a childhood-onset neurobehavioral disorder. To date, TS is still misdiagnosed due to its varied presentation and lacking of obvious clinical symptoms. Therefore, studies of objective imaging biomarkers are of great importance for early TS diagnosis. As tic generation has been linked to disturbed structural networks, and many efforts have been made recently to investigate brain functional or structural networks using machine learning methods, for the purpose of disease diagnosis. However, few studies were related to TS and some drawbacks still existed in them. Therefore, we propose a novel classification framework integrating a multi-threshold strategy and a network fusion scheme to address the preexisting drawbacks. Here we used diffusion MRI probabilistic tractography to construct the structural networks of 44 TS children and 48 healthy children. We ameliorated the similarity network fusion algorithm specially to fuse the multi-threshold structural networks. Graph theoretical analysis was then implemented, and nodal degree, nodal efficiency and nodal betweenness centrality were selected as features. Finally, support vector machine recursive feature extraction (SVM-RFE) algorithm was used for feature selection, and then optimal features are fed into SVM to automatically discriminate TS children from controls. We achieved a high accuracy of 89.13% evaluated by a nested cross validation, demonstrated the superior performance of our framework over other comparison methods. The involved discriminative regions for classification primarily located in the basal ganglia and frontal cortico-cortical networks, all highly related to the pathology of TS. Together, our study may provide potential neuroimaging biomarkers for early-stage TS diagnosis.

  5. Acoustic and Perceptual Effects of Left–Right Laryngeal Asymmetries Based on Computational Modeling

    PubMed Central

    Samlan, Robin A.; Story, Brad H.; Lotto, Andrew J.; Bunton, Kate

    2015-01-01

    Purpose Computational modeling was used to examine the consequences of 5 different laryngeal asymmetries on acoustic and perceptual measures of vocal function. Method A kinematic vocal fold model was used to impose 5 laryngeal asymmetries: adduction, edge bulging, nodal point ratio, amplitude of vibration, and starting phase. Thirty /a/ and /I/ vowels were generated for each asymmetry and analyzed acoustically using cepstral peak prominence (CPP), harmonics-to-noise ratio (HNR), and 3 measures of spectral slope (H1*-H2*, B0-B1, and B0-B2). Twenty listeners rated voice quality for a subset of the productions. Results Increasingly asymmetric adduction, bulging, and nodal point ratio explained significant variance in perceptual rating (R2 = .05, p < .001). The same factors resulted in generally decreasing CPP, HNR, and B0-B2 and in increasing B0-B1. Of the acoustic measures, only CPP explained significant variance in perceived quality (R2 = .14, p < .001). Increasingly asymmetric amplitude of vibration or starting phase minimally altered vocal function or voice quality. Conclusion Asymmetries of adduction, bulging, and nodal point ratio drove acoustic measures and perception in the current study, whereas asymmetric amplitude of vibration and starting phase demonstrated minimal influence on the acoustic signal or voice quality. PMID:24845730

  6. Enhanced retroviral gene delivery in ultrasonic standing wave fields.

    PubMed

    Lee, Y-H; Peng, C-A

    2005-04-01

    Enhancement of retroviral transduction efficiency has been achieved by several physical and chemical approaches. However, the application of those methods is hampered by not easily scalable configurations. In this study, instead of looking into the effect of sonoporation, the potential of ultrasonic standing wave fields (USWF) to facilitate retroviral transduction rate was explored. We reasoned that, driven by the primary acoustic radiation force, suspended cells moved to the pressure nodal planes first and formed cell bands. Nanometer-sized retroviruses, circulated between nodal planes by acoustic microstreaming, then used the preformed cell bands as the nucleating sites to attach on. As a result, the encounter opportunity between retroviruses and cells was increased and further facilitated the gene delivery efficiency. Our results showed that mega-Hertz USWF brought K562 erythroleukemia cells (10(6) cells/ml) and vesicular stomatitis virus G-protein (VSV-G) pseudotyped retroviruses (titer of 5 x 10(6) CFU/ml) into close contact at the pressure nodal planes, yielding a four-fold increment of enhanced green fluorescent protein transgene expression after 5-min USWF exposure in the presence of Polybrene. Furthermore, with a fixed titer of retrovirus, the transduction rate was augmented with the increase of cell concentration. In summary, USWF offer a feasible means to enhance retroviral transduction efficiency in large-scale settings.

  7. Association of Nodal Metastasis and Mortality With Vermilion vs Cutaneous Lip Location in Cutaneous Squamous Cell Carcinoma of the Lip.

    PubMed

    Wang, David M; Kraft, Stefan; Rohani, Pooyan; Murphy, George F; Besaw, Robert J; Karia, Pritesh S; Morgan, Frederick C; Schmults, Chrysalyne D

    2018-06-01

    Although the lip is considered a high-risk location in cutaneous squamous cell carcinoma (cSCC), it has not been established whether this risk stems from vermilion or cutaneous locations or both. To compare differences in risks of recurrence, metastasis, and death from cSCCs on the vermilion vs cutaneous lip. Retrospective cohort study of 303 patients with 310 primary cSCCs of the lip (138 cutaneous, 172 vermilion) diagnosed between 2000 and 2015 at 2 academic tertiary care centers in Boston, Massachusetts. Development of local recurrence, nodal metastasis, distant metastasis, disease-specific death, and all-cause death. Of the 303 study participants with 310 SCCs of the lip, 153 (50.5%) were men, and 150 (49.5%) were women; median age at diagnosis, 68 years (range, 27-93 years). Outcomes were as follows for vermilion vs cutaneous locations: local recurrence, 6.4% (11 of 172) vs 2.9% (4 of 138); nodal metastasis, 7.6% (13 of 172) vs 1.5% (2 of 138); distant metastasis, 0.6% (1 of 172) vs 0.7% (1 of 138); disease-specific death, 3.5% (6 of 172) vs 2.9% (4 of 138); and all-cause death, 26.7% (46 of 172) vs 29.0% (40 of 138). The difference was statistically significant for nodal metastasis (P = .01). In multivariable analysis, nodal metastasis was associated with vermilion lip location (subhazard ratio, 5.0; 95% CI, 1.1-23.8) and invasion beyond fat (fascia or beyond for vermilion lip) (subhazard ratio, 4.4; 95% CI, 1.3-14.9). The risk of nodal metastasis is 5-fold greater for cSCCs on the vermilion lip compared with those on the cutaneous lip. Squamous cell carcinomas of the cutaneous lip have a nodal metastasis risk similar to cSCCs in general (1.5%). Thus, vermilion involvement appears responsible for the increased risk associated with cSCC of lip. Vermilion involvement may merit radiologic nodal staging and inclusion in future tumor staging, since it was independently associated with higher-risk cSCC of the lip region.

  8. Recent advances in understanding the biology of marginal zone lymphoma

    PubMed Central

    Zucca, Emanuele

    2018-01-01

    There are three different marginal zone lymphomas (MZLs): the extranodal MZL of mucosa-associated lymphoid tissue (MALT) type (MALT lymphoma), the splenic MZL, and the nodal MZL. The three MZLs share common lesions and deregulated pathways but also present specific alterations that can be used for their differential diagnosis. Although trisomies of chromosomes 3 and 18, deletions at 6q23, deregulation of nuclear factor kappa B, and chromatin remodeling genes are frequent events in all of them, the three MZLs differ in the presence of recurrent translocations, mutations affecting the NOTCH pathway, and the transcription factor Kruppel like factor 2 ( KLF2) or the receptor-type protein tyrosine phosphatase delta ( PTPRD). Since a better understanding of the molecular events underlying each subtype may have practical relevance, this review summarizes the most recent and main advances in our understanding of the genetics and biology of MZLs. PMID:29657712

  9. Proton beam radiotherapy as part of comprehensive regional nodal irradiation for locally advanced breast cancer.

    PubMed

    Verma, Vivek; Iftekaruddin, Zaid; Badar, Nida; Hartsell, William; Han-Chih Chang, John; Gondi, Vinai; Pankuch, Mark; Gao, Ming; Schmidt, Stacey; Kaplan, Darren; McGee, Lisa

    2017-05-01

    This study evaluates acute toxicity outcomes in breast cancer patients treated with adjuvant proton beam therapy (PBT). From 2011 to 2016, 91 patients (93 cancers) were treated with adjuvant PBT targeting the intact breast/chest wall and comprehensive regional nodes including the axilla, supraclavicular fossa, and internal mammary lymph nodes. Toxicity was recorded weekly during treatment, one month following treatment, and then every 6months according to the Common Terminology Criteria for Adverse Events (CTCAE) v4.0. Charts were retrospectively reviewed to verify toxicities, patient parameters, disease and treatment characteristics, and disease-related outcomes. Median follow-up was 15.5months. Median PBT dose was 50.4 Gray relative biological effectiveness (GyRBE), with subsequent boost as clinically indicated (N=61, median 10 GyRBE). Chemotherapy, when administered, was given adjuvantly (N=42) or neoadjuvantly (N=46). Grades 1, 2, and 3 dermatitis occurred in 23%, 72%, and 5%, respectively. Eight percent required treatment breaks owing to dermatitis. Median time to resolution of dermatitis was 32days. Grades 1, 2, and 3 esophagitis developed in 31%, 33%, and 0%, respectively. PBT displays acceptable toxicity in the setting of comprehensive regional nodal irradiation. Copyright © 2017. Published by Elsevier B.V.

  10. L1CAM expression in endometrial carcinomas: an ENITEC collaboration study

    PubMed Central

    van der Putten, Louis JM; Visser, Nicole CM; van de Vijver, Koen; Santacana, Maria; Bronsert, Peter; Bulten, Johan; Hirschfeld, Marc; Colas, Eva; Gil-Moreno, Antonio; Garcia, Angel; Mancebo, Gemma; Alameda, Fransesc; Trovik, Jone; Kopperud, Reidun K; Huvila, Jutta; Schrauwen, Stefanie; Koskas, Martin; Walker, Francine; Weinberger, Vit; Minar, Lubos; Jandakova, Eva; Snijders, Marc PLM; van den Berg-van Erp, Saskia; Matias-Guiu, Xavier; Salvesen, Helga B; Amant, Frederic; Massuger, Leon FAG; Pijnenborg, Johanna MA

    2016-01-01

    Background: Identification of aggressive endometrioid endometrial carcinomas (EECs) and non-endometrioid carcinomas (NEECs) is essential to improve outcome. L1 cell adhesion molecule (L1CAM) expression is a strong prognostic marker in stage I EECs, but less is known about L1CAM expression in advanced-stage EECs and NEECs. This study analyses L1CAM expression in a clinically representative cohort of endometrial carcinomas. Methods: The expression of L1CAM was immunohistochemically determined in 1199 endometrial carcinomas, treated at one of the European Network for Individualized Treatment of Endometrial Cancer (ENITEC) centres. Staining was considered positive when >10% of the tumour cells expressed L1CAM. The association between L1CAM expression and several clincopathological characteristics and disease outcome was calculated. Results: In all, L1CAM was expressed in 10% of the 935 stage I EECs, 18% of the 160 advanced stage EECs, and 75% of the 104 NEECs. The expression of L1CAM was associated with advanced stage, nodal involvement, high tumour grade, non-endometrioid histology, lymphovascular space invasion, and distant recurrences in all cases, and with reduced survival in the EECs, but not in the NEECs. Conclusions: The expression of L1CAM is a strong predictor of poor outcome in EECs, but not NEECs. It is strongly associated with non-endometrioid histology and distant spread, and could improve the postoperative selection of high-risk endometrial carcinomas. The value of L1CAM expression in the preoperative selection of high-risk endometrial carcinomas should be studied. PMID:27505134

  11. Lefty Blocks a Subset of TGFβ Signals by Antagonizing EGF-CFC Coreceptors

    PubMed Central

    Cheng, Simon K; Olale, Felix; Brivanlou, Ali H

    2004-01-01

    Members of the EGF-CFC family play essential roles in embryonic development and have been implicated in tumorigenesis. The TGFβ signals Nodal and Vg1/GDF1, but not Activin, require EGF-CFC coreceptors to activate Activin receptors. We report that the TGFβ signaling antagonist Lefty also acts through an EGF-CFC-dependent mechanism. Lefty inhibits Nodal and Vg1 signaling, but not Activin signaling. Lefty genetically interacts with EGF-CFC proteins and competes with Nodal for binding to these coreceptors. Chimeras between Activin and Nodal or Vg1 identify a 14 amino acid region that confers independence from EGF-CFC coreceptors and resistance to Lefty. These results indicate that coreceptors are targets for both TGFβ agonists and antagonists and suggest that subtle sequence variations in TGFβ signals result in greater ligand diversity. PMID:14966532

  12. Neurula rotation determines left-right asymmetry in ascidian tadpole larvae.

    PubMed

    Nishide, Kazuhiko; Mugitani, Michio; Kumano, Gaku; Nishida, Hiroki

    2012-04-01

    Tadpole larvae of the ascidian Halocynthia roretzi show morphological left-right asymmetry. The tail invariably bends towards the left side within the vitelline membrane. The structure of the larval brain is remarkably asymmetric. nodal, a conserved gene that shows left-sided expression, is also expressed on the left side in H. roretzi but in the epidermis unlike in vertebrates. We show that nodal signaling at the late neurula stage is required for stereotypic morphological left-right asymmetry at later stages. We uncover a novel mechanism to break embryonic symmetry, in which rotation of whole embryos provides the initial cue for left-sided expression of nodal. Two hours prior to the onset of nodal expression, the neurula embryo rotates along the anterior-posterior axis in a counterclockwise direction when seen in posterior view, and then this rotation stops when the left side of the embryo is oriented downwards. It is likely that epidermis monocilia, which appear at the neurula rotation stage, generate the driving force for the rotation. When the embryo lies on the left side, protrusion of the neural fold physically prevents it from rotating further. Experiments in which neurula rotation is perturbed by various means, including centrifugation and sandwiching between glass, indicate that contact of the left epidermis with the vitelline membrane as a consequence of neurula rotation promotes nodal expression in the left epidermis. We suggest that chemical, and not mechanical, signals from the vitelline membrane promote nodal expression. Neurula rotation is also conserved in other ascidian species.

  13. Interplay between short-range correlated disorder and Coulomb interaction in nodal-line semimetals

    NASA Astrophysics Data System (ADS)

    Wang, Yuxuan; Nandkishore, Rahul M.

    2017-09-01

    In nodal-line semimetals, Coulomb interactions and short-range correlated disorder are both marginal perturbations to the clean noninteracting Hamiltonian. We analyze their interplay using a weak-coupling renormalization group approach. In the clean case, the Coulomb interaction has been found to be marginally irrelevant, leading to Fermi liquid behavior. We extend the analysis to incorporate the effects of disorder. The nodal line structure gives rise to kinematical constraints similar to that for a two-dimensional Fermi surface, which plays a crucial role in the one-loop renormalization of the disorder couplings. For a twofold degenerate nodal loop (Weyl loop), we show that disorder flows to strong coupling along a unique fixed trajectory in the space of symmetry inequivalent disorder couplings. Along this fixed trajectory, all symmetry inequivalent disorder strengths become equal. For a fourfold degenerate nodal loop (Dirac loop), disorder also flows to strong coupling, however, the strengths of symmetry inequivalent disorder couplings remain different. We show that feedback from disorder reverses the sign of the beta function for the Coulomb interaction, causing the Coulomb interaction to flow to strong coupling as well. However, the Coulomb interaction flows to strong coupling asymptotically more slowly than disorder. Extrapolating our results to strong coupling, we conjecture that at low energies nodal line semimetals should be described by a noninteracting nonlinear sigma model. We discuss the relation of our results with possible many-body localization at zero temperatures in such materials.

  14. Orbital nodal surfaces: Topological challenges for density functionals

    NASA Astrophysics Data System (ADS)

    Aschebrock, Thilo; Armiento, Rickard; Kümmel, Stephan

    2017-06-01

    Nodal surfaces of orbitals, in particular of the highest occupied one, play a special role in Kohn-Sham density-functional theory. The exact Kohn-Sham exchange potential, for example, shows a protruding ridge along such nodal surfaces, leading to the counterintuitive feature of a potential that goes to different asymptotic limits in different directions. We show here that nodal surfaces can heavily affect the potential of semilocal density-functional approximations. For the functional derivatives of the Armiento-Kümmel (AK13) [Phys. Rev. Lett. 111, 036402 (2013), 10.1103/PhysRevLett.111.036402] and Becke88 [Phys. Rev. A 38, 3098 (1988), 10.1103/PhysRevA.38.3098] energy functionals, i.e., the corresponding semilocal exchange potentials, as well as the Becke-Johnson [J. Chem. Phys. 124, 221101 (2006), 10.1063/1.2213970] and van Leeuwen-Baerends (LB94) [Phys. Rev. A 49, 2421 (1994), 10.1103/PhysRevA.49.2421] model potentials, we explicitly demonstrate exponential divergences in the vicinity of nodal surfaces. We further point out that many other semilocal potentials have similar features. Such divergences pose a challenge for the convergence of numerical solutions of the Kohn-Sham equations. We prove that for exchange functionals of the generalized gradient approximation (GGA) form, enforcing correct asymptotic behavior of the potential or energy density necessarily leads to irregular behavior on or near orbital nodal surfaces. We formulate constraints on the GGA exchange enhancement factor for avoiding such divergences.

  15. Enhancement of neuronal differentiation by using small molecules modulating Nodal/Smad, Wnt/β-catenin, and FGF signaling.

    PubMed

    Song, Yonghee; Lee, Somyung; Jho, Eek-Hoon

    2018-06-08

    Pluripotent embryonic stem cells are one of the best modalities for the disease treatment due to their potential for self-renewal and differentiation into various cell types. Induction of stem cell differentiation into specific cell lineages has been investigated for decades, especially in vitro neuronal differentiation of embryonic stem cells. However, in vitro differentiation methods do not yield sufficient amounts of neurons for use in the therapeutic treatment of neurological disorders. Here, we provide an improved neuronal differentiation method based on a combination of small regulatory molecules for specific signaling pathways (FGF4 for FGF signaling, SB431542 for Nodal/Smad signaling, and XAV939 and BIO for Wnt signaling) in N2B27 media. We found that FGF4 was required for neural induction, SB431542 accelerated neural precursor differentiation, and treatment with XAV939 and BIO at different periods enhanced neuronal differentiation. These optimized neuronal differentiation conditions may allow a greater neuron cell yield within a shorter time than current methods and be the basis for treatment of neurological dysfunction using stem cells. Copyright © 2018. Published by Elsevier Inc.

  16. Cervical nodal metastases in squamous cell carcinoma of the head and neck: what to expect.

    PubMed

    Mukherji, S K; Armao, D; Joshi, V M

    2001-11-01

    The treatment and management of malignancies of the head and neck is directly altered by the presence of metastatic cervical adenopathy. The treatment of nodal metastases in squamous cell carcinoma of the head and neck (HNSCCA) is determined by the lymphatic drainage of the upper aerodigestive tract. The lymphatic drainage is site-specific and occurs in a predictable manner. The purpose of this text is to provide an overview of the normal routes of lymphatic drainage in the head and neck and correlate this with the current nodal classification system. The specific aims of this manuscript are to 1) illustrate the expected lymphatic drainage patterns of HNSCCA arising in the different subsites (nasopharynx, oropharynx, oral cavity, larynx, and hypopharynx) and 2) review the expected frequency of metastases within nodal groups for HNSCCA that arise in these locations. An understanding of the topographical distribution and incidence of cervical lymph node metastases plays an integral role in the physical examination and radiological evaluation of patients with HNSCCA. For the neuroradiologist, this information may increases the ability to identify those nodal groups at risk for metastatic involvement. Copyright 2001 John Wiley & Sons, Inc. Head Neck 23: 995-1005, 2001.

  17. Theory of nodal s ±-wave pairing symmetry in the Pu-based 115 superconductor family

    DOE PAGES

    Das, Tanmoy; Zhu, Jian -Xin; Graf, Matthias J.

    2015-02-27

    The spin-fluctuation mechanism of superconductivity usually results in the presence of gapless or nodal quasiparticle states in the excitation spectrum. Nodal quasiparticle states are well established in copper-oxide, and heavy-fermion superconductors, but not in iron-based superconductors. Here, we study the pairing symmetry and mechanism of a new class of plutonium-based high-T c superconductors and predict the presence of a nodal s⁺⁻ wave pairing symmetry in this family. Starting from a density-functional theory (DFT) based electronic structure calculation we predict several three-dimensional (3D) Fermi surfaces in this 115 superconductor family. We identify the dominant Fermi surface “hot-spots” in the inter-band scatteringmore » channel, which are aligned along the wavevector Q = (π, π, π), where degeneracy could induce sign-reversal of the pairing symmetry. Our calculation demonstrates that the s⁺⁻ wave pairing strength is stronger than the previously thought d-wave pairing; and more importantly, this pairing state allows for the existence of nodal quasiparticles. Finally, we predict the shape of the momentum- and energy-dependent magnetic resonance spectrum for the identification of this pairing symmetry.« less

  18. Saddle-like topological surface states on the T T'X family of compounds (T , T' = Transition metal, X =Si , Ge)

    NASA Astrophysics Data System (ADS)

    Singh, Bahadur; Zhou, Xiaoting; Lin, Hsin; Bansil, Arun

    2018-02-01

    Topological nodal-line semimetals are exotic conductors that host symmetry-protected conducting nodal lines in their bulk electronic spectrum and nontrivial drumhead states on the surface. Based on first-principles calculations and an effective model analysis, we identify the presence of topological nodal-line semimetal states in the low crystalline symmetric T T'X family of compounds (T ,T' = transition metal, X = Si or Ge) in the absence of spin-orbit coupling (SOC). Taking ZrPtGe as an exemplar system, we show that owing to small lattice symmetry this material harbors a single nodal line on the ky=0 plane with large energy dispersion and unique drumhead surface state with a saddlelike energy dispersion. When the SOC is included, the nodal line gaps out and the system transitions to a strong topological insulator state with Z2=(1 ;000 ) . The topological surface state evolves from the drumhead surface state via the sharing of its saddlelike energy dispersion within the bulk energy gap. These features differ remarkably from those of the currently known topological surface states in topological insulators such as Bi2Se3 with Dirac-cone-like energy dispersions.

  19. Active control of sound transmission through a rectangular panel using point-force actuators and piezoelectric film sensors.

    PubMed

    Sanada, Akira; Higashiyama, Kouji; Tanaka, Nobuo

    2015-01-01

    This study deals with the active control of sound transmission through a rectangular panel, based on single input, single output feedforward vibration control using point-force actuators and piezoelectric film sensors. It focuses on the phenomenon in which the sound power transmitted through a finite-sized panel drops significantly at some frequencies just below the resonance frequencies of the panel in the low-frequency range as a result of modal coupling cancellation. In a previous study, it was shown that when point-force actuators are located on nodal lines for the frequency at which this phenomenon occurs, a force equivalent to the incident sound wave can act on the panel. In this study, a practical method for sensing volume velocity using a small number of piezoelectric film strips is investigated. It is found that two quadratically shaped piezoelectric film strips, attached at the same nodal lines as those where the actuators were placed, can sense the volume velocity approximately in the low-frequency range. Results of simulations show that combining the proposed actuation method and the sensing method can achieve a practical control effect at low frequencies over a wide frequency range. Finally, experiments are carried out to demonstrate the validity and feasibility of the proposed method.

  20. F18 FDG positron emission tomography revelation of primary testicular lymphoma with concurrent multiple extra nodal involvement

    PubMed Central

    Vamsy, Mohana; Dattatreya, PS; Parakh, Megha; Dayal, Monal; Rao, VVS Prabhakar

    2013-01-01

    Primary testicular lymphoma (PTL) a relatively rare disease of non-Hodgkin's lymphomas occurring with a lesser incidence of 1-2% has a propensity to occur at later ages above 50 years. PTL spreads to extra nodal sites due to deficiency of extra cellular adhesion molecules. We present detection of multiple sites of extra nodal involvement of PTL by F-18 positron emission tomography/computed tomography study aiding early detection of the dissemination thus aiding in staging and management. PMID:24019676

  1. Target volume delineation for radical radiotherapy of early oesophageal carcinoma in elderly patients.

    PubMed

    Su, J; Zhu, S; Liu, Z; Zhao, Y; Song, C

    2017-02-01

    To compare the prognosis of elderly patients with early oesophageal carcinoma between radical elective nodal prophylactic irradiation and involved-field irradiation and to estimate the failure modes and adverse effects, then to provide the patients the safe and individual therapeutic regimens. The charts of 96 patients aged 65 and over with early stage oesophageal carcinoma receiving radical radiotherapy in our department were retrospectively analysed. Of all the patients, 49 received elective nodal prophylactic irradiation and the other 47 received involved-field irradiation. After completion of the whole treatment, we analysed short-term effects, tumour local control, overall survival of the patients, failure modes and adverse effects. The 1-, 3-, and 5-year local control rate in elective nodal irradiation and involved-field irradiation groups were 80.6%, 57.4%, 54.0% and 65.4%, 46.5%, 30.5% respectively, and the difference was statistically significant (χ 2 =4.478, P=0.03). The differences of overall survival and progression-free survival were not significant (P>0.05). The difference of 1-, 3-, and 5-years local regional failure rate was statistically significant between elective nodal prophylactic irradiation and involved-field irradiation groups, except for the overall failure and distant metastasis rates. The overall incidence of radiation-induced oesophagitis after elective nodal irradiation or involved-field irradiation was 79.6% and 59.6%, and the difference was statistically significant (χ 2 =4.559, P=0.03). The difference of radiation pneumonitis between elective nodal prophylactic irradiation and involved-field irradiation was not significant (12.2% vs 14.9%; χ 2 =0.144, P=0.7). For elderly patients with early stage oesophageal carcinoma receiving radical radiotherapy, although elective nodal prophylactic irradiation could increase the incidence of radiation-induced oesophagitis, patients could tolerate the treatment and benefit from local control. Copyright © 2016 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  2. The Importance of Electron Correlation on Stacking Interaction of Adenine-Thymine Base-Pair Step in B-DNA: A Quantum Monte Carlo Study.

    PubMed

    Hongo, Kenta; Cuong, Nguyen Thanh; Maezono, Ryo

    2013-02-12

    We report fixed-node diffusion Monte Carlo (DMC) calculations of stacking interaction energy between two adenine(A)-thymine(T) base pairs in B-DNA (AA:TT), for which reference data are available, obtained from a complete basis set estimate of CCSD(T) (coupled-cluster with singles, doubles, and perturbative triples). We consider four sets of nodal surfaces obtained from self-consistent field calculations and examine how the different nodal surfaces affect the DMC potential energy curves of the AA:TT molecule and the resulting stacking energies. We find that the DMC potential energy curves using the different nodes look similar to each other as a whole. We also benchmark the performance of various quantum chemistry methods, including Hartree-Fock (HF) theory, second-order Møller-Plesset perturbation theory (MP2), and density functional theory (DFT). The DMC and recently developed DFT results of the stacking energy reasonably agree with the reference, while the HF, MP2, and conventional DFT methods give unsatisfactory results.

  3. On displacement-based plastic design of parallel chord vierendeel girders

    NASA Astrophysics Data System (ADS)

    Grigorian, Mark

    2014-09-01

    The paper introduces the principles of displacement-based plastic design (DBPD) and its applications to the efficient design of parallel chord steel vierendeel girders under normal nodal forces. A simplifying assumption has been made that the mathematical model is composed of imaginary, pin connected modules that fit within the bays of the prototype. The use of this modeling concept in conjunction with the applications of the uniform strength theory leads to the development of an algorithm that is ideally suited for manual, minimum weight design of steel vierendeel girders under any distribution of vertical nodal forces. The resulting solutions are exact and unique and lend themselves well to DBPD and minimum weight treatment. In DBPD which is akin to performance control, member strengths and stiffnesses are assigned rather than tested. Several generic examples have been provided to illustrate the applications of the proposed design procedures. The numerical results of these examples have been verified through long hand and computer methods of analysis. An extensive proof of the proposed method of approach has been provided in the "Appendix".

  4. An entropy stable nodal discontinuous Galerkin method for the two dimensional shallow water equations on unstructured curvilinear meshes with discontinuous bathymetry

    NASA Astrophysics Data System (ADS)

    Wintermeyer, Niklas; Winters, Andrew R.; Gassner, Gregor J.; Kopriva, David A.

    2017-07-01

    We design an arbitrary high-order accurate nodal discontinuous Galerkin spectral element approximation for the non-linear two dimensional shallow water equations with non-constant, possibly discontinuous, bathymetry on unstructured, possibly curved, quadrilateral meshes. The scheme is derived from an equivalent flux differencing formulation of the split form of the equations. We prove that this discretization exactly preserves the local mass and momentum. Furthermore, combined with a special numerical interface flux function, the method exactly preserves the mathematical entropy, which is the total energy for the shallow water equations. By adding a specific form of interface dissipation to the baseline entropy conserving scheme we create a provably entropy stable scheme. That is, the numerical scheme discretely satisfies the second law of thermodynamics. Finally, with a particular discretization of the bathymetry source term we prove that the numerical approximation is well-balanced. We provide numerical examples that verify the theoretical findings and furthermore provide an application of the scheme for a partial break of a curved dam test problem.

  5. Parallel Simulation of Three-Dimensional Free-Surface Fluid Flow Problems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    BAER,THOMAS A.; SUBIA,SAMUEL R.; SACKINGER,PHILIP A.

    2000-01-18

    We describe parallel simulations of viscous, incompressible, free surface, Newtonian fluid flow problems that include dynamic contact lines. The Galerlin finite element method was used to discretize the fully-coupled governing conservation equations and a ''pseudo-solid'' mesh mapping approach was used to determine the shape of the free surface. In this approach, the finite element mesh is allowed to deform to satisfy quasi-static solid mechanics equations subject to geometric or kinematic constraints on the boundaries. As a result, nodal displacements must be included in the set of problem unknowns. Issues concerning the proper constraints along the solid-fluid dynamic contact line inmore » three dimensions are discussed. Parallel computations are carried out for an example taken from the coating flow industry, flow in the vicinity of a slot coater edge. This is a three-dimensional free-surface problem possessing a contact line that advances at the web speed in one region but transitions to static behavior in another part of the flow domain. Discussion focuses on parallel speedups for fixed problem size, a class of problems of immediate practical importance.« less

  6. Shallow active-source imaging of an andesite dike in southern New Mexico: comparing Reftek Texan and Fairfield Z-Land recordings

    NASA Astrophysics Data System (ADS)

    Karplus, M. S.; Kaip, G.; Harder, S. H.; Johnson, K.

    2016-12-01

    In October 2015, the Advanced Exploration Seismology class at the University of Texas at El Paso together with additional volunteers acquired a 500-m active-source seismic profile across an andesite dike adjacent to the Rio Grande River near Sunland Park, New Mexico. Receivers included 100 RT-125 Reftek Texans with 4.5-Hz geophones, spaced every 5 m, and 47 Fairfield Z-Land nodes incorporating 5-Hz 3C geophones, spaced approximately every 10 m. A 8-gauge, 400 grain seismic gun source was fired every 5-10 m along most of the profile. Several locations at the ends of the profile experienced multiple gun shots, which have been stacked to increase signal-to-noise. We discuss similarities and differences in field methods and data acquired using the Texans compared to the nodes for a shallow active-source experiment. We extend the discussion to other types of active-source experiments using other recently-acquired nodal datasets. We observe changes in velocity between the andesite dike and surrounding lithologies, and create a seismic reflection image of the andesite dike.

  7. Therapeutic aspects of endoscopic ultrasound

    NASA Astrophysics Data System (ADS)

    Woodward, Timothy A.

    1999-06-01

    Endoscopic ultrasound (EUS) is a technology that had been used primarily as a passive imaging modality. Recent advances have enabled us to move beyond the use of EUS solely as a staging tool to an interventional device. Current studies suggest that interventional applications of EUS will allow for minimally invasive assessment and therapies in a cost-effective manner. Endoscopic ultrasound with fine needle aspiration (EUS-FNA) has been demonstrated to be a technically feasible, relatively safe method of obtaining cytologic specimens. The clinical utility of EUS- FNA appears to be greatest in the diagnosis and staging of pancreatic cancer and in the nodal staging of gastrointestinal and pulmonary malignancies. In addition, EUS-FNA has demonstrated utility in the sampling pleural and ascitic fluid not generally appreciated or assessable to standard interventions. Interventional applications of EUS include EUS-guided pseudocyst drainage, EUS-guided injection of botulinum toxin in the treatment of achalasia, and EUS- guided celiac plexus neurolysis in the treatment of pancreatic cancer pain. Finally, EUS-guided fine-needle installation is being evaluated, in conjunction with recent bimolecular treatment modalities, as a delivery system in the treatment of certain gastrointestinal tumors.

  8. Review analysis of medullary carcinoma of the thyroid: a 15-year Indian experience.

    PubMed

    Dorairajan, N; Siddharth, D; Kanna, Srinivasulu

    2006-01-01

    The aim of this study was to emphasize the importance of adequate primary surgery in cases of medullary carcinoma of the thyroid. We retrospectively reviewed 44 cases of medullary carcinoma of the thyroid treated in Government General Hospital, Chennai between 1987 and 2002. Patients who underwent total thyroidectomy with only central compartment dissection were compared with those who had undergone total thyroidectomy with meticulous triple compartment (bilateral lateral and central groups) nodal dissection. The group of total thyroidectomy with only central compartment dissection had a high rate of lymph nodal recurrence and persistent hypercalcitoninemia compared with the group with total thyroidectomy with meticulous triple compartment nodal dissection. (chi square, 4.503; P > 0.05). Primary surgery with total thyroidectomy with meticulous triple compartment dissection is superior to total thyroidectomy with central compartment dissection alone in terms of preventing nodal and local recurrences and achieving normal (basal and stimulated) serum calcitonin levels postoperatively.

  9. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Deka, Deepjyoti; Backhaus, Scott N.; Chertkov, Michael

    Limited placement of real-time monitoring devices in the distribution grid, recent trends notwithstanding, has prevented the easy implementation of demand-response and other smart grid applications. Part I of this paper discusses the problem of learning the operational structure of the grid from nodal voltage measurements. In this work (Part II), the learning of the operational radial structure is coupled with the problem of estimating nodal consumption statistics and inferring the line parameters in the grid. Based on a Linear-Coupled(LC) approximation of AC power flows equations, polynomial time algorithms are designed to identify the structure and estimate nodal load characteristics and/ormore » line parameters in the grid using the available nodal voltage measurements. Then the structure learning algorithm is extended to cases with missing data, where available observations are limited to a fraction of the grid nodes. The efficacy of the presented algorithms are demonstrated through simulations on several distribution test cases.« less

  10. Cryopreservation of in vitro grown nodal segments of Rauvolfia serpentina by PVS2 vitrification.

    PubMed

    Ray, Avik; Bhattacharya, Sabita

    2008-01-01

    This paper describes the cryopreservation by PVS2 vitrification of Rauvolfia serpentina (L.) Benth ex kurz, an important tropical medicinal plant. The effects of type and size of explants, sucrose preculture (duration and concentration) and vitrification treatment were tested. Preliminary experiments with PVS1, 2 and 3 produced shoot growth only for PVS2. When optimizing the PVS2 vitrification of nodal segments, those of 0.31 - 0.39 cm in size were better than other nodal sizes and or apices. Sucrose preculture had a positive role in survival and subsequent regrowth of the cryopreserved explants. Seven days on 0.5 M sucrose solution significantly improved the viability of nodal segments. PVS2 incubation for 45 minutes combined with a 7-day preculture gave the optimum result of 66 percent. Plantlets derived after cryopreservation resumed growth and regenerated normally.

  11. Constructing a polynomial whose nodal set is the three-twist knot 52

    NASA Astrophysics Data System (ADS)

    Dennis, Mark R.; Bode, Benjamin

    2017-06-01

    We describe a procedure that creates an explicit complex-valued polynomial function of three-dimensional space, whose nodal lines are the three-twist knot 52. The construction generalizes a similar approach for lemniscate knots: a braid representation is engineered from finite Fourier series and then considered as the nodal set of a certain complex polynomial which depends on an additional parameter. For sufficiently small values of this parameter, the nodal lines form the three-twist knot. Further mathematical properties of this map are explored, including the relationship of the phase critical points with the Morse-Novikov number, which is nonzero as this knot is not fibred. We also find analogous functions for other simple knots and links. The particular function we find, and the general procedure, should be useful for designing knotted fields of particular knot types in various physical systems.

  12. Isospectral discrete and quantum graphs with the same flip counts and nodal counts

    NASA Astrophysics Data System (ADS)

    Juul, Jonas S.; Joyner, Christopher H.

    2018-06-01

    The existence of non-isomorphic graphs which share the same Laplace spectrum (to be referred to as isospectral graphs) leads naturally to the following question: what additional information is required in order to resolve isospectral graphs? It was suggested by Band, Shapira and Smilansky that this might be achieved by either counting the number of nodal domains or the number of times the eigenfunctions change sign (the so-called flip count) (Band et al 2006 J. Phys. A: Math. Gen. 39 13999–4014 Band and Smilansky 2007 Eur. Phys. J. Spec. Top. 145 171–9). Recent examples of (discrete) isospectral graphs with the same flip count and nodal count have been constructed by Ammann by utilising Godsil–McKay switching (Ammann private communication). Here, we provide a simple alternative mechanism that produces systematic examples of both discrete and quantum isospectral graphs with the same flip and nodal counts.

  13. Three-dimensional graphdiyne as a topological nodal-line semimetal

    NASA Astrophysics Data System (ADS)

    Nomura, Takafumi; Habe, Tetsuro; Sakamoto, Ryota; Koshino, Mikito

    2018-05-01

    We study the electronic band structure of three-dimensional ABC-stacked (rhombohedral) graphdiyne, which is a new planar carbon allotrope recently fabricated. Using first-principles calculation, we show that the system is a nodal-line semimetal, in which the conduction band and valence band cross at a closed ring in the momentum space. We derive the minimum tight-binding model and the low-energy effective Hamiltonian in a 4 ×4 matrix form. The nodal line is protected by a nontrivial winding number, and it ensures the existence of the topological surface state in a finite-thickness slab. The Fermi surface of the doped system exhibits a peculiar, self-intersecting hourglass structure, which is quite different from the torus or pipe shape in the previously proposed nodal semimetals. Despite its simple configuration, three-dimensional graphdiyne offers unique electronic properties distinct from any other carbon allotropes.

  14. Coexistence of tunable Weyl points and topological nodal lines in ternary transition-metal telluride TaIrT e4

    NASA Astrophysics Data System (ADS)

    Zhou, Xiaoqing; Liu, Qihang; Wu, QuanSheng; Nummy, Tom; Li, Haoxiang; Griffith, Justin; Parham, Stephen; Waugh, Justin; Emmanouilidou, Eve; Shen, Bing; Yazyev, Oleg V.; Ni, Ni; Dessau, Daniel

    2018-06-01

    We report a combined theoretical and experimental study on TaIrT e4 , a potential candidate for a minimal model of type-II Weyl semimetals. Unexpectedly, an intriguing node structure with 12 Weyl points and a pair of nodal lines protected by mirror symmetry was found by first-principles calculations. Some signatures of the complex electronic structure, such as topologically nontrivial band crossings and topologically trivial Fermi arcs, are cross-validated by angle-resolved photoemission spectroscopy. Through external strain, the number of Weyl points can be reduced to a theoretical minimum of four, and the appearance of the nodal lines can be switched between different mirror planes in momentum space. The coexistence of switchable Weyl points and nodal lines establishes transition-metal chalcogenides as a unique test ground for topological state characterization and engineering.

  15. Pharmacological therapy in children with nodal reentry tachycardia: when, how and how long to treat the affected patients.

    PubMed

    Bouhouch, R; El Houari, T; Fellat, I; Arharbi, M

    2008-01-01

    Atrio-ventricular nodal reentrant tachycardia (AVNRT) is a rare supra-ventricular tachycardia (SVT) in children and becomes more frequent in adolescents. Most of children with an AVNRT have a healthy heart thus rarely experiencing severe symptoms. Because of haemodynamic instability or risk of complications, recurrences of SVT may require a chronic therapy. Interruption of dual atrio-ventricular nodal physiology is the basic mechanism to terminate AVNRT. This may be achieved by using anti-arrhythmic drugs or through Radiofrequency catheter ablation (RF). We aim to review the literature on the use of anti-arrhythmic drugs for the management of AVNRT in children aged more than 1 year and discuss the recommended dosages and the duration of a long term therapy. In the absence of comparative trials of risks and benefits between pharmacological therapy and RF and because of a greater clinical experience with anti-arrhythmic drugs, these last but not the least continue to be first-line therapy in the management of most SVT in children. Trials on pharmacotherapy in children with SVT in general and AVNRT in particular are lacking, use of anti-arrhythmic drugs being extrapolated from adult literature. Although Adenosine is becoming more used since it is the safest and effective drug in the acute setting, Digoxin continue to be the drug of first choice. Beta-blockers and Class I anti-arrhythmic are the second choice drugs with Flecainide being the preferred anti-arrhythmic drug for treatment failures. Amiodarone is rarely used as a chronic therapy in resistant cases. With the new advances in the RF technology, this therapy is becoming more safe and effective for AVNRT in children. Therefore, additional well-designed controlled trials are needed to further evaluate the comparative efficacy of anti-arrhythmic drugs in the management of AVNRT in children, as well as to evaluate dosing and toxicity in various age groups and determine the duration of a chronic therapy as compared to a potential RF.

  16. Spectral algorithm for non-destructive damage localisation: Application to an ancient masonry arch model

    NASA Astrophysics Data System (ADS)

    Masciotta, Maria-Giovanna; Ramos, Luís F.; Lourenço, Paulo B.; Vasta, Marcello

    2017-02-01

    Structural monitoring and vibration-based damage identification methods are fundamental tools for condition assessment and early-stage damage identification, especially when dealing with the conservation of historical constructions and the maintenance of strategic civil structures. However, although the substantial advances in the field, several issues must still be addressed to broaden the application range of such tools and to assert their reliability. This study deals with the experimental validation of a novel method for non-destructive damage identification purposes. This method is based on the use of spectral output signals and has been recently validated by the authors through a numerical simulation. After a brief insight into the basic principles of the proposed approach, the spectral-based technique is applied to identify the experimental damage induced on a masonry arch through statically increasing loading. Once the direct and cross spectral density functions of the nodal response processes are estimated, the system's output power spectrum matrix is built and decomposed in eigenvalues and eigenvectors. The present study points out how the extracted spectral eigenparameters contribute to the damage analysis allowing to detect the occurrence of damage and to locate the target points where the cracks appear during the experimental tests. The sensitivity of the spectral formulation to the level of noise in the modal data is investigated and discussed. As a final evaluation criterion, the results from the spectrum-driven method are compared with the ones obtained from existing non-model based damage identification methods.

  17. Radiotherapy for esthesioneuroblastoma: is elective nodal irradiation warranted in the multimodality treatment approach?

    PubMed

    Noh, O Kyu; Lee, Sang-wook; Yoon, Sang Min; Kim, Sung Bae; Kim, Sang Yoon; Kim, Chang Jin; Jo, Kyung Ja; Choi, Eun Kyung; Song, Si Yeol; Kim, Jong Hoon; Ahn, Seung Do

    2011-02-01

    The role of elective nodal irradiation (ENI) in radiotherapy for esthesioneuroblastoma (ENB) has not been clearly defined. We analyzed treatment outcomes of patients with ENB and the frequency of cervical nodal failure in the absence of ENI. Between August 1996 and December 2007, we consulted with 19 patients with ENB regarding radiotherapy. Initial treatment consisted of surgery alone in 2 patients; surgery and postoperative radiotherapy in 4; surgery and adjuvant chemotherapy in 1; surgery, postoperative radiotherapy, and chemotherapy in 3; and chemotherapy followed by radiotherapy or concurrent chemoradiotherapy in 5. Five patients did not receive planned radiotherapy because of disease progression. Including 2 patients who received salvage radiotherapy, 14 patients were treated with radiotherapy. Elective nodal irradiation was performed in 4 patients with high-risk factors, including 3 with cervical lymph node metastasis at presentation. Fourteen patients were analyzable, with a median follow-up of 27 months (range, 7-64 months). The overall 3-year survival rate was 73.4%. Local failure occurred in 3 patients (21.4%), regional cervical failure in 3 (21.4%), and distant failure in 2 (14.3%). No cervical nodal failure occurred in patients treated with combined systemic chemotherapy regardless of ENI. Three cervical failures occurred in the 4 patients treated with ENI or neck dissection (75%), none of whom received systemic chemotherapy. ENI during radiotherapy for ENB seems to play a limited role in preventing cervical nodal failure. Omitting ENI may be an option if patients are treated with a combination of radiotherapy and chemotherapy. Copyright © 2011 Elsevier Inc. All rights reserved.

  18. Tactical Decision Making: A Proposed Evaluation Criteria Model for the Infantry Battalion’s Tactical Estimate during Offensive Operations

    DTIC Science & Technology

    1993-06-04

    34 J In a paper entitled "Understanding and Developing Combat Power," by Colonel Huba Vass de Czege, a method identifying analytical techniques for...reiterates several important doctrinal and theoretical requirements for the de ’elopment of 9« an optimal «valuation criteria nodal. Although...Methode de Ralsonnenent Tactlque" (The Tactical Reasoning Method)’". Is a version of concurrent COA analysis under conditions at uncertainty. Figure

  19. Asynchronous collision integrators: Explicit treatment of unilateral contact with friction and nodal restraints

    PubMed Central

    Wolff, Sebastian; Bucher, Christian

    2013-01-01

    This article presents asynchronous collision integrators and a simple asynchronous method treating nodal restraints. Asynchronous discretizations allow individual time step sizes for each spatial region, improving the efficiency of explicit time stepping for finite element meshes with heterogeneous element sizes. The article first introduces asynchronous variational integration being expressed by drift and kick operators. Linear nodal restraint conditions are solved by a simple projection of the forces that is shown to be equivalent to RATTLE. Unilateral contact is solved by an asynchronous variant of decomposition contact response. Therein, velocities are modified avoiding penetrations. Although decomposition contact response is solving a large system of linear equations (being critical for the numerical efficiency of explicit time stepping schemes) and is needing special treatment regarding overconstraint and linear dependency of the contact constraints (for example from double-sided node-to-surface contact or self-contact), the asynchronous strategy handles these situations efficiently and robust. Only a single constraint involving a very small number of degrees of freedom is considered at once leading to a very efficient solution. The treatment of friction is exemplified for the Coulomb model. Special care needs the contact of nodes that are subject to restraints. Together with the aforementioned projection for restraints, a novel efficient solution scheme can be presented. The collision integrator does not influence the critical time step. Hence, the time step can be chosen independently from the underlying time-stepping scheme. The time step may be fixed or time-adaptive. New demands on global collision detection are discussed exemplified by position codes and node-to-segment integration. Numerical examples illustrate convergence and efficiency of the new contact algorithm. Copyright © 2013 The Authors. International Journal for Numerical Methods in Engineering published by John Wiley & Sons, Ltd. PMID:23970806

  20. Germline BRCA Mutations Are Associated With Higher Risk of Nodal Involvement, Distant Metastasis, and Poor Survival Outcomes in Prostate Cancer

    PubMed Central

    Castro, Elena; Goh, Chee; Olmos, David; Saunders, Ed; Leongamornlert, Daniel; Tymrakiewicz, Malgorzata; Mahmud, Nadiya; Dadaev, Tokhir; Govindasami, Koveela; Guy, Michelle; Sawyer, Emma; Wilkinson, Rosemary; Ardern-Jones, Audrey; Ellis, Steve; Frost, Debra; Peock, Susan; Evans, D. Gareth; Tischkowitz, Marc; Cole, Trevor; Davidson, Rosemarie; Eccles, Diana; Brewer, Carole; Douglas, Fiona; Porteous, Mary E.; Donaldson, Alan; Dorkins, Huw; Izatt, Louise; Cook, Jackie; Hodgson, Shirley; Kennedy, M. John; Side, Lucy E.; Eason, Jacqueline; Murray, Alex; Antoniou, Antonis C.; Easton, Douglas F.; Kote-Jarai, Zsofia; Eeles, Rosalind

    2013-01-01

    Purpose To analyze the baseline clinicopathologic characteristics of prostate tumors with germline BRCA1 and BRCA2 (BRCA1/2) mutations and the prognostic value of those mutations on prostate cancer (PCa) outcomes. Patients and Methods This study analyzed the tumor features and outcomes of 2,019 patients with PCa (18 BRCA1 carriers, 61 BRCA2 carriers, and 1,940 noncarriers). The Kaplan-Meier method and Cox regression analysis were used to evaluate the associations between BRCA1/2 status and other PCa prognostic factors with overall survival (OS), cause-specific OS (CSS), CSS in localized PCa (CSS_M0), metastasis-free survival (MFS), and CSS from metastasis (CSS_M1). Results PCa with germline BRCA1/2 mutations were more frequently associated with Gleason ≥ 8 (P = .00003), T3/T4 stage (P = .003), nodal involvement (P = .00005), and metastases at diagnosis (P = .005) than PCa in noncarriers. CSS was significantly longer in noncarriers than in carriers (15.7 v 8.6 years, multivariable analyses [MVA] P = .015; hazard ratio [HR] = 1.8). For localized PCa, 5-year CSS and MFS were significantly higher in noncarriers (96% v 82%; MVA P = .01; HR = 2.6%; and 93% v 77%; MVA P = .009; HR = 2.7, respectively). Subgroup analyses confirmed the poor outcomes in BRCA2 patients, whereas the role of BRCA1 was not well defined due to the limited size and follow-up in this subgroup. Conclusion Our results confirm that BRCA1/2 mutations confer a more aggressive PCa phenotype with a higher probability of nodal involvement and distant metastasis. BRCA mutations are associated with poor survival outcomes and this should be considered for tailoring clinical management of these patients. PMID:23569316

  1. Robot-assisted Salvage Lymph Node Dissection for Clinically Recurrent Prostate Cancer.

    PubMed

    Montorsi, Francesco; Gandaglia, Giorgio; Fossati, Nicola; Suardi, Nazareno; Pultrone, Cristian; De Groote, Ruben; Dovey, Zach; Umari, Paolo; Gallina, Andrea; Briganti, Alberto; Mottrie, Alexandre

    2017-09-01

    Salvage lymph node dissection has been described as a feasible treatment for the management of prostate cancer patients with nodal recurrence after primary treatment. To report perioperative, pathologic, and oncologic outcomes of robot-assisted salvage nodal dissection (RASND) in patients with nodal recurrence after radical prostatectomy (RP). We retrospectively evaluated 16 patients affected by nodal recurrence following RP documented by positive positron emission tomography/computed tomography scan. Surgery was performed using DaVinci Si and Xi systems. A pelvic nodal dissection that included lymphatic stations overlying the external, internal, and common iliac vessels, the obturator fossa, and the presacral nodes was performed. In 13 (81.3%) patients a retroperitoneal lymph node dissection that included all nodal tissue located between the aortic bifurcation and the renal vessels was performed. Perioperative outcomes consisted of operative time, blood loss, length of hospital stay, and complications occurred within 30 d after surgery. Biochemical response (BR) was defined as a prostate-specific antigen level <0.2 ng/ml at 40 d after RASND. Median operative time, blood loss, and length of hospital stay were 210min, 250ml, and 3.5 d. The median number of nodes removed was 16.5. Positive lymph nodes were detected in 11 (68.8%) patients. Overall, four (25.0%) and five (31.2%) patients experienced intraoperative and postoperative complications, respectively. Overall, one (6.3%) and four (25.0%) patients had Clavien I and II complications within 30 d after RASND, respectively. Overall, five (33.3%) patients experienced BR after surgery. Our study is limited by the small cohort of patients evaluated and by the follow-up duration. RASND represents a feasible procedure in patients with nodal recurrence after RP and provides acceptable short-term oncologic outcomes, where one out of three patients experience BR immediately after surgery. Long-term data are needed to confirm the effectiveness of this approach. We report our initial experience with robot-assisted salvage nodal dissection for the management of patients with lymph node recurrence after radical prostatectomy. This technique represents a feasible and effective approach, where no high-grade complications were recorded and one out of three patients experienced biochemical response at 40 d after surgery. Copyright © 2016 European Association of Urology. Published by Elsevier B.V. All rights reserved.

  2. A nodally condensed SUPG formulation for free-surface computation of steady-state flows constrained by unilateral contact - Application to rolling

    NASA Astrophysics Data System (ADS)

    Arora, Shitij; Fourment, Lionel

    2018-05-01

    In the context of the simulation of industrial hot forming processes, the resultant time-dependent thermo-mechanical multi-field problem (v →,p ,σ ,ɛ ) can be sped up by 10-50 times using the steady-state methods while compared to the conventional incremental methods. Though the steady-state techniques have been used in the past, but only on simple configurations and with structured meshes, and the modern-days problems are in the framework of complex configurations, unstructured meshes and parallel computing. These methods remove time dependency from the equations, but introduce an additional unknown into the problem: the steady-state shape. This steady-state shape x → can be computed as a geometric correction t → on the domain X → by solving the weak form of the steady-state equation v →.n →(t →)=0 using a Streamline Upwind Petrov Galerkin (SUPG) formulation. There exists a strong coupling between the domain shape and the material flow, hence, a two-step fixed point iterative resolution algorithm was proposed that involves (1) the computation of flow field from the resolution of thermo-mechanical equations on a prescribed domain shape and (2) the computation of steady-state shape for an assumed velocity field. The contact equations are introduced in the penalty form both during the flow computation as well as during the free-surface correction. The fact that the contact description is inhomogeneous, i.e., it is defined in the nodal form in the former, and in the weighted residual form in the latter, is assumed to be critical to the convergence of certain problems. Thus, the notion of nodal collocation is invoked in the weak form of the surface correction equation to homogenize the contact coupling. The surface correction algorithm is tested on certain analytical test cases and the contact coupling is tested with some hot rolling problems.

  3. Somatic profiling of the epidermal growth factor receptor pathway in tumours from patients with advanced colorectal cancer, treated with chemotherapy ± cetuximab

    PubMed Central

    Smith, Christopher G.; Fisher, David; Claes, Bart; Maughan, Timothy S.; Idziaszczyk, Shelley; Peuteman, Gilian; Harris, Rebecca; James, Michelle D.; Meade, Angela; Jasani, Bharat; Adams, Richard A.; Kenny, Sarah; Kaplan, Richard; Lambrechts, Diether; Cheadle, Jeremy P.

    2013-01-01

    Purpose To study the somatic molecular profile of the epidermal growth factor receptor (EGFR) pathway in advanced CRC (aCRC), its relationship to prognosis, the site of the primary and metastases, and response to cetuximab. Experimental Design We used Sequenom and Pyrosequencing for high-throughput somatic profiling the EGFR pathway in 1,976 tumours from patients with aCRC from the COIN trial (oxaliplatin and fluoropyrimidine chemotherapy ±cetuximab). Correlations between mutations, clinico-pathological, response and survival data were carried out. Results Sequenom and Pyrosequencing had 99.0% (9961/10063) genotype concordance. We identified thirteen different KRAS mutations in 42.3% of aCRCs, two BRAF mutations in 9.0%, four NRAS mutations in 3.6% and five PIK3CA mutations in 12.7%. 4.2% of aCRCs had microsatellite instability (MSI). KRAS and PIK3CA exon 9, but not exon 20, mutations co-occurred (P=8.9×10−4) as did MSI and BRAF mutations (P=5.3×10−10). KRAS mutations were associated with right colon cancers (P=5.2×10−5) and BRAF mutations with right (P=7.2×10−5) and transverse colon (P=9.8×10−6) cancers. KRAS mutations were associated with lung-only metastases (P=2.3×10−4), BRAF mutations with peritoneal (P=9.2×10−4) and nodal-only (P=3.7×10−5) metastases, and MSI (BRAFWT) with nodal-only metastases (P=2.9×10−4). MSI (BRAFWT) was associated with worse survival (HR=1.89, 95% CI 1.30-2.76, P=8.5×10−4). No mutations, subsets of mutations, or MSI-status were associated with response to cetuximab. Conclusions Our data support a functional co-operation between KRAS and PIK3CA in colorectal tumourigenesis and link somatic profiles to the sites of metastases. MSI was associated with poor prognosis in advanced disease, and no individual somatic profile was associated with response to cetuximab in COIN. PMID:23741067

  4. Modeling Percolation in Polymer Nanocomposites by Stochastic Microstructuring

    PubMed Central

    Soto, Matias; Esteva, Milton; Martínez-Romero, Oscar; Baez, Jesús; Elías-Zúñiga, Alex

    2015-01-01

    A methodology was developed for the prediction of the electrical properties of carbon nanotube-polymer nanocomposites via Monte Carlo computational simulations. A two-dimensional microstructure that takes into account waviness, fiber length and diameter distributions is used as a representative volume element. Fiber interactions in the microstructure are identified and then modeled as an equivalent electrical circuit, assuming one-third metallic and two-thirds semiconductor nanotubes. Tunneling paths in the microstructure are also modeled as electrical resistors, and crossing fibers are accounted for by assuming a contact resistance associated with them. The equivalent resistor network is then converted into a set of linear equations using nodal voltage analysis, which is then solved by means of the Gauss–Jordan elimination method. Nodal voltages are obtained for the microstructure, from which the percolation probability, equivalent resistance and conductivity are calculated. Percolation probability curves and electrical conductivity values are compared to those found in the literature. PMID:28793594

  5. Voltage collapse in complex power grids

    PubMed Central

    Simpson-Porco, John W.; Dörfler, Florian; Bullo, Francesco

    2016-01-01

    A large-scale power grid's ability to transfer energy from producers to consumers is constrained by both the network structure and the nonlinear physics of power flow. Violations of these constraints have been observed to result in voltage collapse blackouts, where nodal voltages slowly decline before precipitously falling. However, methods to test for voltage collapse are dominantly simulation-based, offering little theoretical insight into how grid structure influences stability margins. For a simplified power flow model, here we derive a closed-form condition under which a power network is safe from voltage collapse. The condition combines the complex structure of the network with the reactive power demands of loads to produce a node-by-node measure of grid stress, a prediction of the largest nodal voltage deviation, and an estimate of the distance to collapse. We extensively test our predictions on large-scale systems, highlighting how our condition can be leveraged to increase grid stability margins. PMID:26887284

  6. EGFR immunoexpression, RAS immunoexpression and their effects on survival in lung adenocarcinoma cases.

    PubMed

    Gundogdu, Ahmet Gokhan; Onder, Sevgen; Firat, Pinar; Dogan, Riza

    2014-06-01

    The impacts of epidermal growth factor receptor (EGFR) immunoexpression and RAS immunoexpression on the survival and prognosis of lung adenocarcinoma patients are debated in the literature. Twenty-six patients, who underwent pulmonary resections between 2002 and 2007 in our clinic, and whose pathologic examinations yielded adenocarcinoma, were included in the study. EGFR and RAS expression levels were examined by immunohistochemical methods. The results were compared with the survival, stage of the disease, nodal involvement, lymphovascular invasion, and pleural invasion. Nonparametric bivariate analyses were used for statistical analyses. A significant link between EGFR immunoexpression and survival has been identified while RAS immunoexpression and survival have been proven to be irrelevant. Neither EGFR, nor RAS has displayed a significant link with the stage of the disease, nodal involvement, lymphovascular invasion, or pleural invasion. Positive EGFR immunoexpression affects survival negatively, while RAS immunoexpression has no effect on survival in lung adenocarcinoma patients.

  7. Nodal Stage of Surgically Resected Non-Small Cell Lung Cancer and Its Effect on Recurrence Patterns and Overall Survival

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Varlotto, John M., E-mail: john.varlotto@umassmemorial.org; Yao, Aaron N.; DeCamp, Malcolm M.

    Purpose: Current National Comprehensive Cancer Network guidelines recommend postoperative radiation therapy (PORT) for patients with resected non-small cell lung cancer (NSCLC) with N2 involvement. We investigated the relationship between nodal stage and local-regional recurrence (LR), distant recurrence (DR) and overall survival (OS) for patients having an R0 resection. Methods and Materials: A multi-institutional database of consecutive patients undergoing R0 resection for stage I-IIIA NSCLC from 1995 to 2008 was used. Patients receiving any radiation therapy before relapse were excluded. A total of 1241, 202, and 125 patients were identified with N0, N1, and N2 involvement, respectively; 161 patients received chemotherapy.more » Cumulative incidence rates were calculated for LR and DR as first sites of failure, and Kaplan-Meier estimates were made for OS. Competing risk analysis and proportional hazards models were used to examine LR, DR, and OS. Independent variables included age, sex, surgical procedure, extent of lymph node sampling, histology, lymphatic or vascular invasion, tumor size, tumor grade, chemotherapy, nodal stage, and visceral pleural invasion. Results: The median follow-up time was 28.7 months. Patients with N1 or N2 nodal stage had rates of LR similar to those of patients with N0 disease, but were at significantly increased risk for both DR (N1, hazard ratio [HR] = 1.84, 95% confidence interval [CI]: 1.30-2.59; P=.001; N2, HR = 2.32, 95% CI: 1.55-3.48; P<.001) and death (N1, HR = 1.46, 95% CI: 1.18-1.81; P<.001; N2, HR = 2.33, 95% CI: 1.78-3.04; P<.001). LR was associated with squamous histology, visceral pleural involvement, tumor size, age, wedge resection, and segmentectomy. The most frequent site of LR was the mediastinum. Conclusions: Our investigation demonstrated that nodal stage is directly associated with DR and OS but not with LR. Thus, even some patients with, N0-N1 disease are at relatively high risk of local recurrence. Prospective identification of risk factors for local recurrence may aid in selecting an appropriate population for further study of postoperative radiation therapy.« less

  8. Nexus networks in carbon honeycombs

    NASA Astrophysics Data System (ADS)

    Chen, Yuanping; Xie, Yuee; Gao, Yan; Chang, Po-Yao; Zhang, Shengbai; Vanderbilt, David

    2018-04-01

    Nexus metals represent a new type of topological material in which nodal lines merge at nexus points. Here we propose novel networks in nexus systems through intertwining between nexus fermions and additional nodal lines. These nexus networks can be realized in recently synthesized carbon honeycomb materials. In these carbon honeycombs, we demonstrate a phase transition between a nexus network and a system with triply degenerate points and additional nodal lines. The Landau level spectra show unusual magnetic transport properties in the nexus networks. Our results pave the way toward realizations of new topological materials with novel transport properties beyond standard Weyl/Dirac semimetals.

  9. Long period nodal motion of sun synchronous orbits

    NASA Technical Reports Server (NTRS)

    Duck, K. I.

    1975-01-01

    An approximative model is formulated for assessing these perturbations that significantly affect long term modal motion of sun synchronous orbits. Computer simulations with several independent computer programs consider zonal and tesseral gravitational harmonics, third body gravitational disturbances induced by the sun and the moon, and atmospheric drag. A pendulum model consisting of evenzonal harmonics through order 4 and solar gravity dominated nodal motion approximation. This pendulum motion results from solar gravity inducing an inclination oscillation which couples into the nodal precession induced by the earth's oblateness. The pendulum model correlated well with simulations observed flight data.

  10. [Does nodal irradiation (clavicular and internal mammary chains) increase the toxicity of adjuvant breast radiotherapy?].

    PubMed

    Riou, O; Bourgier, C; Fenoglietto, P; Azria, D

    2015-06-01

    Treatment volume is a major risk factor of radiation-induced toxicity. As nodal irradiation increases treatment volume, radiation toxicity should be greater. Nevertheless, scientific randomised data do not support this fact. However, a radiation-induced toxicity is possible outside tangential fields in the nodal volumes not related to breast-only treatment. Treatment should not be adapted only to the disease but personalized to the individual risk of toxicity for each patient. Copyright © 2015 Société française de radiothérapie oncologique (SFRO). Published by Elsevier SAS. All rights reserved.

  11. Nodal signalling in Xenopus: the role of Xnr5 in left/right asymmetry and heart development.

    PubMed

    Tadjuidje, Emmanuel; Kofron, Matthew; Mir, Adnan; Wylie, Christopher; Heasman, Janet; Cha, Sang-Wook

    2016-08-01

    Nodal class TGF-β signalling molecules play essential roles in establishing the vertebrate body plan. In all vertebrates, nodal family members have specific waves of expression required for tissue specification and axis formation. In Xenopus laevis, six nodal genes are expressed before gastrulation, raising the question of whether they have specific roles or act redundantly with each other. Here, we examine the role of Xnr5. We find it acts at the late blastula stage as a mesoderm inducer and repressor of ectodermal gene expression, a role it shares with Vg1. However, unlike Vg1, Xnr5 depletion reduces the expression of the nodal family member xnr1 at the gastrula stage. It is also required for left/right laterality by controlling the expression of the laterality genes xnr1, antivin (lefty) and pitx2 at the tailbud stage. In Xnr5-depleted embryos, the heart field is established normally, but symmetrical reduction in Xnr5 levels causes a severely stunted midline heart, first evidenced by a reduction in cardiac troponin mRNA levels, while left-sided reduction leads to randomization of the left/right axis. This work identifies Xnr5 as the earliest step in the signalling pathway establishing normal heart laterality in Xenopus. © 2016 The Authors.

  12. GDF3 is a BMP inhibitor that can activate Nodal signaling only at very high doses

    PubMed Central

    Levine, Ariel J.; Levine, Zachary J.; Brivanlou, Ali H.

    2013-01-01

    Within the TGF-β superfamily, there are approximately forty ligands divided into two major branches: the TGF-β/Activin/Nodal ligands and the BMP/GDF ligands. We studied the ligand GDF3 and found that it inhibits signaling by its co-family members, the BMPs; however, GDF3 has been described by others to have Nodal-like activity. Here, we show that GDF3 can activate Nodal signaling, but only at very high doses and only upon mRNA over-expression. In contrast, GDF3 inhibits BMP signaling upon over-expression of GDF3 mRNA, as recombinant protein, and regardless of its dose. We therefore further characterized the mechanism through which GDF3 protein acts as a specific BMP inhibitor and found that the BMP inhibitory activity of GDF3 resides redundantly in the unprocessed, predominant form and in the mature form of the protein. These results confirm and extend the activity that we described for GDF3 and illuminate the experimental basis for the different observations of others. We suggest that GDF3 is either a bi-functional TGF-β ligand, or, more likely, that it is a BMP inhibitor that can artificially activate Nodal signaling under non-physiological conditions. PMID:18823971

  13. Fatty Acid Profile, Phenolics and Flavonoids Contents in Olea europaea L. Callus Culture cv. cornicabra.

    PubMed

    Rodríguez-Hernandez, Ludwi; Nájera-Gomez, Humberto; Luján-Hidalgo, Maria Celína; Ruiz-Lau, Nancy; Lecona-Guzmán, Carlos Alberto; Abud-Archila, Miguel; Ruíz-Valdiviezo, Víctor Manuel; Gutiérrez-Miceli, Federico Antonio

    2018-05-01

    Olive trees are one of the most important oil crops in the world due to the sensorial and nutritional characteristics of olive oil, such as lipid composition and antioxidant content, and the medicinal properties of its leaves. In this paper, callus formation was induced using nodal segments of olive tree (Olea europaea cv. cornicabra) as explants. Fatty acid profile, total phenolic compounds and total flavonoid compounds were determined in callus culture after 15 weeks and compared with leaf and nodal segments tissues. There was no statistical difference in phenolic compounds among leaf, nodal segments and callus culture, whereas flavonoid compounds were higher in leaf. Fatty acid profile was similar in leaf, nodal segments and callus culture and was constituted by hexadecanoic acid, octadecanoic acid, cis-9-octadecenoic acid, cis-9,12-octadecadienoic acid, cis-9,12,15-octadecatrienoic acid. Hexadecanoic acid was the main fatty acid in callus, leaf and nodal segments with 35.0, 39.0 and 40.0% (w/w), of the lipid composition, respectively. With this paper, it is being reported for the first time the capacity of callus culture to accumulate fatty acids. Our results could serve to continue studying the production of fatty acids in callus cultivation as a biotechnological tool to improve different olive cultivars.

  14. Nodal-chain metals.

    PubMed

    Bzdušek, Tomáš; Wu, QuanSheng; Rüegg, Andreas; Sigrist, Manfred; Soluyanov, Alexey A

    2016-10-06

    The band theory of solids is arguably the most successful theory of condensed-matter physics, providing a description of the electronic energy levels in various materials. Electronic wavefunctions obtained from the band theory enable a topological characterization of metals for which the electronic spectrum may host robust, topologically protected, fermionic quasiparticles. Many of these quasiparticles are analogues of the elementary particles of the Standard Model, but others do not have a counterpart in relativistic high-energy theories. A complete list of possible quasiparticles in solids is lacking, even in the non-interacting case. Here we describe the possible existence of a hitherto unrecognized type of fermionic excitation in metals. This excitation forms a nodal chain-a chain of connected loops in momentum space-along which conduction and valence bands touch. We prove that the nodal chain is topologically distinct from previously reported excitations. We discuss the symmetry requirements for the appearance of this excitation and predict that it is realized in an existing material, iridium tetrafluoride (IrF 4 ), as well as in other compounds of this class of materials. Using IrF 4 as an example, we provide a discussion of the topological surface states associated with the nodal chain. We argue that the presence of the nodal-chain fermions will result in anomalous magnetotransport properties, distinct from those of materials exhibiting previously known excitations.

  15. The prognostic value of node status in different breast cancer subtypes

    PubMed Central

    Hou, Xin-Wei; Chi, Jiang-Rui; Ge, Jie; Wang, Xin; Cao, Xu-Chen

    2017-01-01

    Nodal metastases and breast cancer subtypes (BCS) are both well-recognized prognostic indicators. However, the association between nodal metastases and BCS, and the prognostic value of nodal metastases in different BCS are still remains unclear. Our aim was to investigate the association between nodal metastases and BCS, and the prognostic value of nodal metastases in the different BCS. We found that the breast cancer subtype was closely associated with the pN stage. pN stage and breast cancer subtype were significantly associated with disease-free survival. The subgroup analysis showed that the patients in higher pN stage had a poor outcome than patients in lower pN stage in each breast cancer subtype. Furthermore, when the analysis was stratified by breast cancer subtype, we found that even in the same pN stage (pN0-pN2), there was significant survival difference among patients in different BCS, and Luminal A breast cancer patients had the best survival outcome. However, there were no significant survival difference between Luminal A patients and other breast cancer subtype when patients in pN3 stage. Thus, our study suggested that both lymph node status and molecular subtype played important roles in the outcome of breast cancer patients and they cannot replace each other. PMID:27999188

  16. Brady's Geothermal Field Nodal Seismometers Metadata

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lesley Parker

    Metadata for the nodal seismometer array deployed at the POROTOMO's Natural Laboratory in Brady Hot Spring, Nevada during the March 2016 testing. Metadata includes location and timing for each instrument as well as file lists of data to be uploaded in a separate submission.

  17. Nodal-line dynamics via exact polynomial solutions for coherent waves traversing aberrated imaging systems.

    PubMed

    Paganin, David M; Beltran, Mario A; Petersen, Timothy C

    2018-03-01

    We obtain exact polynomial solutions for two-dimensional coherent complex scalar fields propagating through arbitrary aberrated shift-invariant linear imaging systems. These solutions are used to model nodal-line dynamics of coherent fields output by such systems.

  18. Acoustic and Perceptual Effects of Left-Right Laryngeal Asymmetries Based on Computational Modeling

    ERIC Educational Resources Information Center

    Samlan, Robin A.; Story, Brad H.; Lotto, Andrew J.; Bunton, Kate

    2014-01-01

    Purpose: Computational modeling was used to examine the consequences of 5 different laryngeal asymmetries on acoustic and perceptual measures of vocal function. Method: A kinematic vocal fold model was used to impose 5 laryngeal asymmetries: adduction, edge bulging, nodal point ratio, amplitude of vibration, and starting phase. Thirty /a/ and /?/…

  19. Evaluation of ADINA. Part I. Theory and Programing Descriptions.

    DTIC Science & Technology

    1980-06-08

    Problem," Numerical and Computer Methods in Structural Mechanics, S. J. Feaves, N. Pe-rone, J. Robinson and W.C. Schnobrich, eds., Academic Press, New...connectivity array N102 ’NDM*NlJME-ITW0 YL Element nodal coordinates N103 ---- NUME IELT Element number of nodes N104 NUME IPST Stress printing flag N105 NUME

  20. Occult Pelvic Lymph Node Involvement in Bladder Cancer: Implications for Definitive Radiation

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Goldsmith, Benjamin; Baumann, Brian C.; He, Jiwei

    2014-03-01

    Purpose: To inform radiation treatment planning for clinically staged, node-negative bladder cancer patients by identifying clinical factors associated with the presence and location of occult pathologic pelvic lymph nodes. Methods and Materials: The records of patients with clinically staged T1-T4N0 urothelial carcinoma of the bladder undergoing radical cystectomy and pelvic lymphadenectomy at a single institution were reviewed. Logistic regression was used to evaluate associations between preoperative clinical variables and occult pathologic pelvic or common iliac lymph nodes. Percentages of patient with involved lymph node regions entirely encompassed within whole bladder (perivesicular nodal region), small pelvic (perivesicular, obturator, internal iliac, andmore » external iliac nodal regions), and extended pelvic clinical target volume (CTV) (small pelvic CTV plus common iliac regions) were calculated. Results: Among 315 eligible patients, 81 (26%) were found to have involved pelvic lymph nodes at the time of surgery, with 38 (12%) having involved common iliac lymph nodes. Risk of occult pathologically involved lymph nodes did not vary with clinical T stage. On multivariate analysis, the presence of lymphovascular invasion (LVI) on preoperative biopsy was significantly associated with occult pelvic nodal involvement (odds ratio 3.740, 95% confidence interval 1.865-7.499, P<.001) and marginally associated with occult common iliac nodal involvement (odds ratio 2.307, 95% confidence interval 0.978-5.441, P=.056). The percentages of patients with involved lymph node regions entirely encompassed by whole bladder, small pelvic, and extended pelvic CTVs varied with clinical risk factors, ranging from 85.4%, 95.1%, and 100% in non-muscle-invasive patients to 44.7%, 71.1%, and 94.8% in patients with muscle-invasive disease and biopsy LVI. Conclusions: Occult pelvic lymph node rates are substantial for all clinical subgroups, especially patients with LVI on biopsy. Extended coverage of pelvic lymph nodes up to the level of the common iliac nodes may be warranted in subsets of patients.« less

  1. Delineation of Internal Mammary Nodal Target Volumes in Breast Cancer Radiation Therapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Jethwa, Krishan R.; Kahila, Mohamed M.; Hunt, Katie N.

    Purpose: The optimal clinical target volume for internal mammary (IM) node irradiation is uncertain in an era of increasingly conformal volume-based treatment planning for breast cancer. We mapped the location of gross internal mammary lymph node (IMN) metastases to identify areas at highest risk of harboring occult disease. Methods and Materials: Patients with axial imaging of IMN disease were identified from a breast cancer registry. The IMN location was transferred onto the corresponding anatomic position on representative axial computed tomography images of a patient in the treatment position and compared with consensus group guidelines of IMN target delineation. Results: Themore » IMN location in 67 patients with 130 IMN metastases was mapped. The location was in the first 3 intercostal spaces in 102 of 130 nodal metastases (78%), whereas 18 of 130 IMNs (14%) were located caudal to the third intercostal space and 10 of 130 IMNs (8%) were located cranial to the first intercostal space. Of the 102 nodal metastases within the first 3 intercostal spaces, 54 (53%) were located within the Radiation Therapy Oncology Group consensus volume. Relative to the IM vessels, 19 nodal metastases (19%) were located medially with a mean distance of 2.2 mm (SD, 2.9 mm) whereas 29 (28%) were located laterally with a mean distance of 3.6 mm (SD, 2.5 mm). Ninety percent of lymph nodes within the first 3 intercostal spaces would have been encompassed within a 4-mm medial and lateral expansion on the IM vessels. Conclusions: In women with indications for elective IMN irradiation, a 4-mm medial and lateral expansion on the IM vessels may be appropriate. In women with known IMN involvement, cranial extension to the confluence of the IM vein with the brachiocephalic vein with or without caudal extension to the fourth or fifth interspace may be considered provided that normal tissue constraints are met.« less

  2. New core-reflector boundary conditions for transient nodal reactor calculations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lee, E.K.; Kim, C.H.; Joo, H.K.

    1995-09-01

    New core-reflector boundary conditions designed for the exclusion of the reflector region in transient nodal reactor calculations are formulated. Spatially flat frequency approximations for the temporal neutron behavior and two types of transverse leakage approximations in the reflector region are introduced to solve the transverse-integrated time-dependent one-dimensional diffusion equation and then to obtain relationships between net current and flux at the core-reflector interfaces. To examine the effectiveness of new core-reflector boundary conditions in transient nodal reactor computations, nodal expansion method (NEM) computations with and without explicit representation of the reflector are performed for Laboratorium fuer Reaktorregelung und Anlagen (LRA) boilingmore » water reactor (BWR) and Nuclear Energy Agency Committee on Reactor Physics (NEACRP) pressurized water reactor (PWR) rod ejection kinetics benchmark problems. Good agreement between two NEM computations is demonstrated in all the important transient parameters of two benchmark problems. A significant amount of CPU time saving is also demonstrated with the boundary condition model with transverse leakage (BCMTL) approximations in the reflector region. In the three-dimensional LRA BWR, the BCMTL and the explicit reflector model computations differ by {approximately}4% in transient peak power density while the BCMTL results in >40% of CPU time saving by excluding both the axial and the radial reflector regions from explicit computational nodes. In the NEACRP PWR problem, which includes six different transient cases, the largest difference is 24.4% in the transient maximum power in the one-node-per-assembly B1 transient results. This difference in the transient maximum power of the B1 case is shown to reduce to 11.7% in the four-node-per-assembly computations. As for the computing time, BCMTL is shown to reduce the CPU time >20% in all six transient cases of the NEACRP PWR.« less

  3. Sensitive molecular detection of small nodal metastasis in uterine cervical cancer using HPV16-E6/CK19/MUC1 cancer biomarkers

    PubMed Central

    Samouëlian, Vanessa; Mechtouf, Nawel; Leblanc, Eric; Cardin, Guillaume B.; Lhotellier, Valérie; Querleu, Denis; Révillion, Françoise; Rodier, Francis

    2018-01-01

    Metastatic nodal involvement is a critical prognostic factor in uterine cervical cancer (UCC). To improve current methods of detecting UCC metastases in lymph nodes (LNs), we used quantitative PCR (qPCR) to assess mRNA expression of potential metastatic biomarkers. We found that expression of HPV16-E6, cytokeratin19 (CK19), and mucin1 (MUC1) is consistently upregulated in tumors and metastatic tissues, supporting a role for these genes in UCC progression. These putative biomarkers were able to predict the presence of histologically positive metastatic LNs with respective sensitivities and specificities of 82% and 99% (CK19), 76% and 95% (HPV16-E6), and 76% and 78% (MUC1). While the biomarkers failed to detect 1.7% to 2.2% of the histologically positive LNs when used individually, combining CK19 and HPV16-E6 enhanced sensitivity and specificity to 100% and 94%, respectively. To explore the sensitivity of qPCR-based detection of varying proportions of invading HPV16-positive UCC cells, we designed a LN metastasis model that achieved a fresh cell detection limit of 0.008% (1:12500 HPV16-positive to HPV16-negative cells), and a paraffin-embedded, formalin-fixed (PEFF) detection limit of 0.02% (1:5000 HPV16-positive to HPV16-negative cells), both of which are within the theoretical detection limit for micrometastasis. Thus, HPV E6/E7 oncogenes may be useful targets for the ultrasensitive detection of nodal involvements like micrometastases in fresh or archived tissue samples. Moreover, our results suggest that the biomarker combination of CK19/HPV-E6 could support a real-time intraoperative strategy for the detection of small, but potentially lethal, metastatic nodal involvements in fresh UCC tissues. PMID:29774091

  4. An approach to model reactor core nodalization for deterministic safety analysis

    NASA Astrophysics Data System (ADS)

    Salim, Mohd Faiz; Samsudin, Mohd Rafie; Mamat @ Ibrahim, Mohd Rizal; Roslan, Ridha; Sadri, Abd Aziz; Farid, Mohd Fairus Abd

    2016-01-01

    Adopting good nodalization strategy is essential to produce an accurate and high quality input model for Deterministic Safety Analysis (DSA) using System Thermal-Hydraulic (SYS-TH) computer code. The purpose of such analysis is to demonstrate the compliance against regulatory requirements and to verify the behavior of the reactor during normal and accident conditions as it was originally designed. Numerous studies in the past have been devoted to the development of the nodalization strategy for small research reactor (e.g. 250kW) up to the bigger research reactor (e.g. 30MW). As such, this paper aims to discuss the state-of-arts thermal hydraulics channel to be employed in the nodalization for RTP-TRIGA Research Reactor specifically for the reactor core. At present, the required thermal-hydraulic parameters for reactor core, such as core geometrical data (length, coolant flow area, hydraulic diameters, and axial power profile) and material properties (including the UZrH1.6, stainless steel clad, graphite reflector) have been collected, analyzed and consolidated in the Reference Database of RTP using standardized methodology, mainly derived from the available technical documentations. Based on the available information in the database, assumptions made on the nodalization approach and calculations performed will be discussed and presented. The development and identification of the thermal hydraulics channel for the reactor core will be implemented during the SYS-TH calculation using RELAP5-3D® computer code. This activity presented in this paper is part of the development of overall nodalization description for RTP-TRIGA Research Reactor under the IAEA Norwegian Extra-Budgetary Programme (NOKEBP) mentoring project on Expertise Development through the Analysis of Reactor Thermal-Hydraulics for Malaysia, denoted as EARTH-M.

  5. Graph Theoretical Analysis of Functional Brain Networks: Test-Retest Evaluation on Short- and Long-Term Resting-State Functional MRI Data

    PubMed Central

    Wang, Jin-Hui; Zuo, Xi-Nian; Gohel, Suril; Milham, Michael P.; Biswal, Bharat B.; He, Yong

    2011-01-01

    Graph-based computational network analysis has proven a powerful tool to quantitatively characterize functional architectures of the brain. However, the test-retest (TRT) reliability of graph metrics of functional networks has not been systematically examined. Here, we investigated TRT reliability of topological metrics of functional brain networks derived from resting-state functional magnetic resonance imaging data. Specifically, we evaluated both short-term (<1 hour apart) and long-term (>5 months apart) TRT reliability for 12 global and 6 local nodal network metrics. We found that reliability of global network metrics was overall low, threshold-sensitive and dependent on several factors of scanning time interval (TI, long-term>short-term), network membership (NM, networks excluding negative correlations>networks including negative correlations) and network type (NT, binarized networks>weighted networks). The dependence was modulated by another factor of node definition (ND) strategy. The local nodal reliability exhibited large variability across nodal metrics and a spatially heterogeneous distribution. Nodal degree was the most reliable metric and varied the least across the factors above. Hub regions in association and limbic/paralimbic cortices showed moderate TRT reliability. Importantly, nodal reliability was robust to above-mentioned four factors. Simulation analysis revealed that global network metrics were extremely sensitive (but varying degrees) to noise in functional connectivity and weighted networks generated numerically more reliable results in compared with binarized networks. For nodal network metrics, they showed high resistance to noise in functional connectivity and no NT related differences were found in the resistance. These findings provide important implications on how to choose reliable analytical schemes and network metrics of interest. PMID:21818285

  6. Identification of nodal tissue in the living heart using rapid scanning fiber-optics confocal microscopy and extracellular fluorophores.

    PubMed

    Huang, Chao; Kaza, Aditya K; Hitchcock, Robert W; Sachse, Frank B

    2013-09-01

    Risks associated with pediatric reconstructive heart surgery include injury of the sinoatrial node (SAN) and atrioventricular node (AVN), requiring cardiac rhythm management using implantable pacemakers. These injuries are the result of difficulties in identifying nodal tissues intraoperatively. Here we describe an approach based on confocal microscopy and extracellular fluorophores to quantify tissue microstructure and identify nodal tissue. Using conventional 3-dimensional confocal microscopy we investigated the microstructural arrangement of SAN, AVN, and atrial working myocardium (AWM) in fixed rat heart. AWM exhibited a regular striated arrangement of the extracellular space. In contrast, SAN and AVN had an irregular, reticulated arrangement. AWM, SAN, and AVN tissues were beneath a thin surface layer of tissue that did not obstruct confocal microscopic imaging. Subsequently, we imaged tissues in living rat hearts with real-time fiber-optics confocal microscopy. Fiber-optics confocal microscopy images resembled images acquired with conventional confocal microscopy. We investigated spatial regularity of tissue microstructure from Fourier analysis and second-order image moments. Fourier analysis of fiber-optics confocal microscopy images showed that the spatial regularity of AWM was greater than that of nodal tissues (37.5 ± 5.0% versus 24.3 ± 3.9% for SAN and 23.8 ± 3.7% for AVN; P<0.05). Similar differences of spatial regularities were revealed from second-order image moments (50.0 ± 7.3% for AWM versus 29.3 ± 6.7% for SAN and 27.3 ± 5.5% for AVN; P<0.05). The study demonstrates feasibility of identifying nodal tissue in living heart using extracellular fluorophores and fiber-optics confocal microscopy. Application of the approach in pediatric reconstructive heart surgery may reduce risks of injuring nodal tissues.

  7. Decision Trees Predicting Tumor Shrinkage for Head and Neck Cancer: Implications for Adaptive Radiotherapy.

    PubMed

    Surucu, Murat; Shah, Karan K; Mescioglu, Ibrahim; Roeske, John C; Small, William; Choi, Mehee; Emami, Bahman

    2016-02-01

    To develop decision trees predicting for tumor volume reduction in patients with head and neck (H&N) cancer using pretreatment clinical and pathological parameters. Forty-eight patients treated with definitive concurrent chemoradiotherapy for squamous cell carcinoma of the nasopharynx, oropharynx, oral cavity, or hypopharynx were retrospectively analyzed. These patients were rescanned at a median dose of 37.8 Gy and replanned to account for anatomical changes. The percentages of gross tumor volume (GTV) change from initial to rescan computed tomography (CT; %GTVΔ) were calculated. Two decision trees were generated to correlate %GTVΔ in primary and nodal volumes with 14 characteristics including age, gender, Karnofsky performance status (KPS), site, human papilloma virus (HPV) status, tumor grade, primary tumor growth pattern (endophytic/exophytic), tumor/nodal/group stages, chemotherapy regimen, and primary, nodal, and total GTV volumes in the initial CT scan. The C4.5 Decision Tree induction algorithm was implemented. The median %GTVΔ for primary, nodal, and total GTVs was 26.8%, 43.0%, and 31.2%, respectively. Type of chemotherapy, age, primary tumor growth pattern, site, KPS, and HPV status were the most predictive parameters for primary %GTVΔ decision tree, whereas for nodal %GTVΔ, KPS, site, age, primary tumor growth pattern, initial primary GTV, and total GTV volumes were predictive. Both decision trees had an accuracy of 88%. There can be significant changes in primary and nodal tumor volumes during the course of H&N chemoradiotherapy. Considering the proposed decision trees, radiation oncologists can select patients predicted to have high %GTVΔ, who would theoretically gain the most benefit from adaptive radiotherapy, in order to better use limited clinical resources. © The Author(s) 2015.

  8. Nodal endoplasmic reticulum, a specialized form of endoplasmic reticulum found in gravity-sensing root tip columella cells

    NASA Technical Reports Server (NTRS)

    Zheng, H. Q.; Staehelin, L. A.

    2001-01-01

    The endoplasmic reticulum (ER) of columella root cap cells has been postulated to play a role in gravity sensing. We have re-examined the ultrastructure of columella cells in tobacco (Nicotiana tabacum) root tips preserved by high-pressure freezing/freeze-substitution techniques to gain more precise information about the organization of the ER in such cells. The most notable findings are: the identification of a specialized form of ER, termed "nodal ER," which is found exclusively in columella cells; the demonstration that the bulk of the ER is organized in the form of a tubular network that is confined to a peripheral layer under the plasma membrane; and the discovery that this ER-rich peripheral region excludes Golgi stacks, vacuoles, and amyloplasts but not mitochondria. Nodal ER domains consist of an approximately 100-nm-diameter central rod composed of oblong subunits to which usually seven sheets of rough ER are attached along their margins. These domains form patches at the interface between the peripheral ER network and the ER-free central region of the cells, and they occupy defined positions within central and flanking columella cells. Over one-half of the nodal ER domains are located along the outer tangential walls of the flanking cells. Cytochalasin D and latrunculin A cause an increase in size and a decrease in numbers of nodal ER domains. We postulate that the nodal ER membranes locally modulate the gravisensing signals produced by the sedimenting amyloplasts, and that the confinement of all ER membranes to the cell periphery serves to enhance the sedimentability of the amyloplasts in the central region of columella cells.

  9. An approach to model reactor core nodalization for deterministic safety analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Salim, Mohd Faiz, E-mail: mohdfaizs@tnb.com.my; Samsudin, Mohd Rafie, E-mail: rafies@tnb.com.my; Mamat Ibrahim, Mohd Rizal, E-mail: m-rizal@nuclearmalaysia.gov.my

    Adopting good nodalization strategy is essential to produce an accurate and high quality input model for Deterministic Safety Analysis (DSA) using System Thermal-Hydraulic (SYS-TH) computer code. The purpose of such analysis is to demonstrate the compliance against regulatory requirements and to verify the behavior of the reactor during normal and accident conditions as it was originally designed. Numerous studies in the past have been devoted to the development of the nodalization strategy for small research reactor (e.g. 250kW) up to the bigger research reactor (e.g. 30MW). As such, this paper aims to discuss the state-of-arts thermal hydraulics channel to bemore » employed in the nodalization for RTP-TRIGA Research Reactor specifically for the reactor core. At present, the required thermal-hydraulic parameters for reactor core, such as core geometrical data (length, coolant flow area, hydraulic diameters, and axial power profile) and material properties (including the UZrH{sub 1.6}, stainless steel clad, graphite reflector) have been collected, analyzed and consolidated in the Reference Database of RTP using standardized methodology, mainly derived from the available technical documentations. Based on the available information in the database, assumptions made on the nodalization approach and calculations performed will be discussed and presented. The development and identification of the thermal hydraulics channel for the reactor core will be implemented during the SYS-TH calculation using RELAP5-3D{sup ®} computer code. This activity presented in this paper is part of the development of overall nodalization description for RTP-TRIGA Research Reactor under the IAEA Norwegian Extra-Budgetary Programme (NOKEBP) mentoring project on Expertise Development through the Analysis of Reactor Thermal-Hydraulics for Malaysia, denoted as EARTH-M.« less

  10. Genetic Analysis Reveals a Hierarchy of Interactions between Polycystin-Encoding Genes and Genes Controlling Cilia Function during Left-Right Determination

    PubMed Central

    Grimes, Daniel T.; Keynton, Jennifer L.; Buenavista, Maria T.; Jin, Xingjian; Patel, Saloni H.; Kyosuke, Shinohara; Williams, Debbie J.; Hamada, Hiroshi; Hussain, Rohanah; Nauli, Surya M.; Norris, Dominic P.

    2016-01-01

    During mammalian development, left-right (L-R) asymmetry is established by a cilia-driven leftward fluid flow within a midline embryonic cavity called the node. This ‘nodal flow’ is detected by peripherally-located crown cells that each assemble a primary cilium which contain the putative Ca2+ channel PKD2. The interaction of flow and crown cell cilia promotes left side-specific expression of Nodal in the lateral plate mesoderm (LPM). Whilst the PKD2-interacting protein PKD1L1 has also been implicated in L-R patterning, the underlying mechanism by which flow is detected and the genetic relationship between Polycystin function and asymmetric gene expression remains unknown. Here, we characterize a Pkd1l1 mutant line in which Nodal is activated bilaterally, suggesting that PKD1L1 is not required for LPM Nodal pathway activation per se, but rather to restrict Nodal to the left side downstream of nodal flow. Epistasis analysis shows that Pkd1l1 acts as an upstream genetic repressor of Pkd2. This study therefore provides a genetic pathway for the early stages of L-R determination. Moreover, using a system in which cultured cells are supplied artificial flow, we demonstrate that PKD1L1 is sufficient to mediate a Ca2+ signaling response after flow stimulation. Finally, we show that an extracellular PKD domain within PKD1L1 is crucial for PKD1L1 function; as such, destabilizing the domain causes L-R defects in the mouse. Our demonstration that PKD1L1 protein can mediate a response to flow coheres with a mechanosensation model of flow sensation in which the force of fluid flow drives asymmetric gene expression in the embryo. PMID:27272319

  11. Universal heat conduction in Ce 1-xYb xCoIn 5: Evidence for robust nodal d-wave superconducting gap

    DOE PAGES

    Xu, Y.; Petrovic, C.; Dong, J. K.; ...

    2016-02-01

    In the heavy-fermion superconductor Ce 1-xYb xCoIn 5, Yb doping was reported to cause a possible change from nodal d-wave superconductivity to a fully gapped d-wave molecular superfluid of composite pairs near x ≈ 0.07 (nominal value x nom = 0.2). Here we present systematic thermal conductivity measurements on Ce 1-xYb xCoIn 5 (x = 0.013, 0.084, and 0.163) single crystals. The observed finite residual linear term κ 0/T is insensitive to Yb doping, verifying the universal heat conduction of the nodal d-wave superconducting gap in Ce 1-xYb xCoIn 5. Similar universal heat conduction is also observed in the CeCo(Inmore » 1–yCd y) 5 system. Furthermore, these results reveal a robust nodal d-wave gap in CeCoIn 5 upon Yb or Cd doping.« less

  12. Disappearance of nodal gap across the insulator-superconductor transition in a copper-oxide superconductor.

    PubMed

    Peng, Yingying; Meng, Jianqiao; Mou, Daixiang; He, Junfeng; Zhao, Lin; Wu, Yue; Liu, Guodong; Dong, Xiaoli; He, Shaolong; Zhang, Jun; Wang, Xiaoyang; Peng, Qinjun; Wang, Zhimin; Zhang, Shenjin; Yang, Feng; Chen, Chuangtian; Xu, Zuyan; Lee, T K; Zhou, X J

    2013-01-01

    The parent compound of the copper-oxide high-temperature superconductors is a Mott insulator. Superconductivity is realized by doping an appropriate amount of charge carriers. How a Mott insulator transforms into a superconductor is crucial in understanding the unusual physical properties of high-temperature superconductors and the superconductivity mechanism. Here we report high-resolution angle-resolved photoemission measurement on heavily underdoped Bi₂Sr₂-xLaxCuO(₆+δ) system. The electronic structure of the lightly doped samples exhibit a number of characteristics: existence of an energy gap along the nodal direction, d-wave-like anisotropic energy gap along the underlying Fermi surface, and coexistence of a coherence peak and a broad hump in the photoemission spectra. Our results reveal a clear insulator-superconductor transition at a critical doping level of ~0.10 where the nodal energy gap approaches zero, the three-dimensional antiferromagnetic order disappears, and superconductivity starts to emerge. These observations clearly signal a close connection between the nodal gap, antiferromagnetism and superconductivity.

  13. Topological Phase Transitions in Line-nodal Superconductors

    NASA Astrophysics Data System (ADS)

    Cho, Gil Young; Han, Sangeun; Moon, Eun-Gook

    Fathoming interplay between symmetry and topology of many-electron wave-functions deepens our understanding in quantum nature of many particle systems. Topology often protects zero-energy excitation, and in a certain class, symmetry is intrinsically tied to the topological protection. Namely, unless symmetry is broken, topological nature is intact. We study one specific case of such class, symmetry-protected line-nodal superconductors in three spatial dimensions (3d). Mismatch between phase spaces of order parameter fluctuation and line-nodal fermion excitation induces an exotic universality class in a drastic contrast to one of the conventional ϕ4 theory in 3d. Hyper-scaling violation and relativistic dynamic scaling with unusually large quantum critical region are main characteristics, and their implication in experiments is discussed. For example, continuous phase transition out of line-nodal superconductors has a linear phase boundary in a temperature-tuning parameter phase-diagram. This work was supported by the Brain Korea 21 PLUS Project of Korea Government and KAIST start-up funding.

  14. Bifurcation behaviors of synchronized regions in logistic map networks with coupling delay

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tang, Longkun, E-mail: tomlk@hqu.edu.cn, E-mail: xqwu@whu.edu.cn; Wu, Xiaoqun, E-mail: tomlk@hqu.edu.cn, E-mail: xqwu@whu.edu.cn; Lu, Jun-an, E-mail: jalu@whu.edu.cn

    2015-03-15

    Network synchronized regions play an extremely important role in network synchronization according to the master stability function framework. This paper focuses on network synchronous state stability via studying the effects of nodal dynamics, coupling delay, and coupling way on synchronized regions in Logistic map networks. Theoretical and numerical investigations show that (1) network synchronization is closely associated with its nodal dynamics. Particularly, the synchronized region bifurcation points through which the synchronized region switches from one type to another are in good agreement with those of the uncoupled node system, and chaotic nodal dynamics can greatly impede network synchronization. (2) Themore » coupling delay generally impairs the synchronizability of Logistic map networks, which is also dominated by the parity of delay for some nodal parameters. (3) A simple nonlinear coupling facilitates network synchronization more than the linear one does. The results found in this paper will help to intensify our understanding for the synchronous state stability in discrete-time networks with coupling delay.« less

  15. The role of nodal and internodal responses in gravitropism and autotropism in Galium aparine L

    NASA Technical Reports Server (NTRS)

    Heathcote, D. G.; Brown, A. H. (Principal Investigator)

    1987-01-01

    This time course and location of gravitropically induced curvatures in stems of goosegrass (Gallium aparine L.), a member of the Rubiaceae, have been investigated. In the early stages of the response (0-5 h), curvature develops throughout the growing region, and is followed by an autotropic straightening which affects the internodes only, leading to the production of essentially straight internodes some 15 h after the onset of gravistimulation. Curvatures developing in the nodal regions, however, continue to increase over this period, and are not subject to reversal by autotropism. The nodal curvatures are not entirely dependent on the presence of any other part of the plant, since marked curvatures can be induced in isolated nodal segments. This pattern of response leads ultimately to correction of the growth direction of the plant by means of curvature responses confined exclusively to the nodes, despite the initial participation of both nodes and internodes in the gravitropic reaction.

  16. Nuclear movement regulated by non-Smad Nodal signaling via JNK is associated with Smad signaling during zebrafish endoderm specification.

    PubMed

    Hozumi, Shunya; Aoki, Shun; Kikuchi, Yutaka

    2017-11-01

    Asymmetric nuclear positioning is observed during animal development, but its regulation and significance in cell differentiation remain poorly understood. Using zebrafish blastulae, we provide evidence that nuclear movement towards the yolk syncytial layer, which comprises extraembryonic tissue, occurs in the first cells fated to differentiate into the endoderm. Nodal signaling is essential for nuclear movement, whereas nuclear envelope proteins are involved in movement through microtubule formation. Positioning of the microtubule-organizing center, which is proposed to be crucial for nuclear movement, is regulated by Nodal signaling and nuclear envelope proteins. The non-Smad JNK signaling pathway, which is downstream of Nodal signaling, regulates nuclear movement independently of the Smad pathway, and this nuclear movement is associated with Smad signal transduction toward the nucleus. Our study provides insight into the function of nuclear movement in Smad signaling toward the nucleus, and could be applied to the control of TGFβ signaling. © 2017. Published by The Company of Biologists Ltd.

  17. Observation of nodal line in non-symmorphic topological semimetal InBi

    DOE PAGES

    Ekahana, Sandy Adhitia; Wu, Shu-Chun; Jiang, Juan; ...

    2017-05-30

    Topological nodal semimetal (TNS), characterized by its touching conduction and valence bands, is a newly discovered state of quantum matter which exhibits various exotic physical phenomena. Recently, a new type of TNS called topological nodal line semimetal (TNLS) is predicted where its conduction and valence band form a degenerate one-dimension line which is further protected by its crystal symmetry. In this work, we systematically investigated the bulk and surface electronic structure of the non-symmorphic, TNLS in InBi (which is also a type II Dirac semimetal) with strong spin–orbit coupling by using angle resolved photoemission spectroscopy. By tracking the crossing points of the bulk bands at the Brillouin zone boundary, we discovered the nodal-line feature along themore » $${{k}}_{{z}}$$ direction, in agreement with the ab initio calculations and confirmed it to be a new compound in the TNLS family. Our discovery provides a new material platform for the study of these exotic topological quantum phases and paves the way for possible future applications.« less

  18. Assessment of nodal involvement in non-small-cell lung cancer with 18F-FDG-PET/CT: mediastinal blood pool cut-off has the highest sensitivity and tumour SUVmax/2 has the highest specificity.

    PubMed

    Mallorie, Amy; Goldring, James; Patel, Anant; Lim, Eric; Wagner, Thomas

    2017-08-01

    Lymph node involvement in non-small-cell lung cancer (NSCLC) is a major factor in determining management and prognosis. We aimed to evaluate the accuracy of fluorine-18-fluorodeoxyglucose-PET/computed tomography (CT) for the assessment of nodal involvement in patients with NSCLC. In this retrospective study, we included 61 patients with suspected or confirmed resectable NSCLC over a 2-year period from April 2013 to April 2015. 221 nodes with pathological staging from surgery or endobronchial ultrasound-guided transbronchial needle aspiration were assessed using a nodal station-based analysis with original clinical reports and three different cut-offs: mediastinal blood pool (MBP), liver background and tumour standardized uptake value maximal (SUVmax)/2. Using nodal station-based analysis for activity more than tumour SUVmax/2, the sensitivity was 45%, the specificity was 89% and the negative predictive value (NPV) was 87%. For activity more than MBP, the sensitivity was 93%, the specificity was 72% and NPV was 98%. For activity more than liver background, the sensitivity was 83%, the specificity was 84% and NPV was 96%. Using a nodal staging-based analysis for accuracy at detecting N2/3 disease, for activity more than tumour SUVmax/2, the sensitivity was 59%, the specificity was 85% and NPV was 80%. For activity more than MBP, the sensitivity was 95%, the specificity was 61% and NPV was 96%. For activity more than liver background, the sensitivity was 86%, the specificity was 81% and NPV was 92%. Receiver-operating characteristic analysis showed the optimal nodal SUVmax to be more than 6.4 with a sensitivity of 45% and a specificity of 95%, with an area under the curve of 0.85. Activity more than MBP was the most sensitive cut-off with the highest sensitivity and NPV. Activity more than primary tumour SUVmax/2 was the most specific cut-off. Nodal SUVmax more than 6.4 has a high specificity of 95%.

  19. Differential membranous E-cadherin expression, cell proliferation and O-GlcNAcylation between primary and metastatic nodal lesion in colorectal cancer.

    PubMed

    Jang, Tae Jung

    2016-02-01

    O-GlcNAcylation is an O-linked β-N-acetylglucosamine (O-GlcNAc) moiety linked to the side chain hydroxyl of a serine or threonine residue. The E-cadherin/β-catenin system, an integral component of epithelial to mesenchymal transition (EMT)/mesenchymal to epithelial transition (MET), is affected through O-GlcNAcylation. The current study examined the status of EMT/MET in both the tumor center and invasive front of the primary colorectal carcinoma (CRC) and metastatic nodal lesions, which were compared to O-GlcNAcylation expression levels in those areas. In addition, the cliniopathological significance of O-GlcNAcylation was studied Immunohistochemical staining for E-cadherin, β-catenin, Snail, O-GlcNAc and Ki67 was performed in 40 primary CRC tissues, 40 nonneoplastic colons, and 17 nodal metastatic lesions. Western blot was also conducted in primary CRC tissue Membranous E-cadherin expression was lowest in the invasive front, but showed greater increases in metastatic nodal lesions. Moreover, its expression level was negatively correlated with that of nuclear β-catenin and Snail. The Ki67 labeling index (LI) was lowest in the invasive front, and increased in metastatic nodal lesions. Primary CRC showed higher expression of O-GlcNAcylation and O-GlcNAc-transferase (OGT) than nonneoplastic colons. O-GlcNAcylation expression decreased in metastatic nodal lesions compared to the invasive front and tumor center, and was inversely correlated with Ki67 LI. However, O-GlcNAcylation expression was only slightly changed between tumor center and invasive front. In addition, there was no correlation between its expression and the level of nuclear β-catenin, membranous E-cadherin and Snail. No significant relationship was observed between O-GlcNAcylation level and cliniopathological parameters. Differential membranous E-cadherin expression, cell proliferation and O-GlcNAcylation in metastatic nodal lesion compared to primary CRC may play role in establishing its lesions; however, these findings are not sufficient to show the role of O-GlcNAcylation in the EMT/MET of CRC. Copyright © 2015 Elsevier GmbH. All rights reserved.

  20. A Stirling engine analysis method based upon moving gas nodes

    NASA Technical Reports Server (NTRS)

    Martini, W. R.

    1986-01-01

    A Lagrangian nodal analysis method for Stirling engines (SEs) is described, validated, and applied to a conventional SE and an isothermalized SE (with fins in the hot and cold spaces). The analysis employs a constant-mass gas node (which moves with respect to the solid nodes during each time step) instead of the fixed gas nodes of Eulerian analysis. The isothermalized SE is found to have efficiency only slightly greater than that of a conventional SE.

  1. Impact of involved field radiotherapy in partial response after doxorubicin-based chemotherapy for advanced aggressive non-Hodgkin's lymphoma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Moser, Elizabeth C.; Kluin-Nelemans, Hanneke C.; Carde, Patrice

    2006-11-15

    Purpose: Whether salvage therapy in patients with advanced aggressive non-Hodgkin's lymphoma (NHL) in partial remission (PR) should consist of radiotherapy or autologous stem-cell transplantation (ASCT) is debatable. We evaluated the impact of radiotherapy on outcome in PR patients treated in four successive European Organization for Research and Treatment of Cancer trials for aggressive NHL. Patients and Methods: Records of 974 patients (1980-1999) were reviewed regarding initial response, final outcome, and type and timing of salvage treatment. After 8 cycles of doxorubicin-based chemotherapy, 227 NHL patients were in PR and treated: 114 received involved field radiotherapy, 16 ASCT, 93 second-line chemotherapy,more » and 4 were operated. Overall survival (OS) and progression-free survival (PFS) after radiotherapy were estimated (Kaplan-Meier method) and compared with other treatments (log-rank). Impact on survival was evaluated by multivariate analysis (Cox proportional hazards model). Results: The median PFS in PR patients was 4.2 years and 48% remained progression-free at 5 years. Half of the PR patients converted to a complete remission. After conversion, survival was comparable to patients directly in complete remission. Radiotherapy resulted in better OS and PFS compared with other treatments, especially in patients with low to intermediate International Prognostic Index score, bulky disease, or nodal disease only. Correction by multivariate analysis for prognostic factors such as stage, bulky disease, and number of extranodal locations showed that radiotherapy was clearly the most significant factor affecting both OS and PFS. Conclusion: This retrospective analysis demonstrates that radiotherapy can be effective for patients in PR after fully dosed chemotherapy; assessment in a randomized trial (radiotherapy vs. ASCT) is justified.« less

  2. Clinical utilities and biological characteristics of melanoma sentinel lymph nodes

    PubMed Central

    Han, Dale; Thomas, Daniel C; Zager, Jonathan S; Pockaj, Barbara; White, Richard L; Leong, Stanley PL

    2016-01-01

    An estimated 73870 people will be diagnosed with melanoma in the United States in 2015, resulting in 9940 deaths. The majority of patients with cutaneous melanomas are cured with wide local excision. However, current evidence supports the use of sentinel lymph node biopsy (SLNB) given the 15%-20% of patients who harbor regional node metastasis. More importantly, the presence or absence of nodal micrometastases has been found to be the most important prognostic factor in early-stage melanoma, particularly in intermediate thickness melanoma. This review examines the development of SLNB for melanoma as a means to determine a patient’s nodal status, the efficacy of SLNB in patients with melanoma, and the biology of melanoma metastatic to sentinel lymph nodes. Prospective randomized trials have guided the development of practice guidelines for use of SLNB for melanoma and have shown the prognostic value of SLNB. Given the rapidly advancing molecular and surgical technologies, the technical aspects of diagnosis, identification, and management of regional lymph nodes in melanoma continues to evolve and to improve. Additionally, there is ongoing research examining both the role of SLNB for specific clinical scenarios and the ways to identify patients who may benefit from completion lymphadenectomy for a positive SLN. Until further data provides sufficient evidence to alter national consensus-based guidelines, SLNB with completion lymphadenectomy remains the standard of care for clinically node-negative patients found to have a positive SLN. PMID:27081640

  3. Review analysis of medullary carcinoma thyroid--15-year Indian experience.

    PubMed

    Dorairajan, N; Saravanakumar, P; Karthikeyan, S; Siddharth, D; Kanna, Srinivasulu

    2005-08-01

    To emphasize the importance of adequate primary surgery in cases of medullary carcinoma of the thyroid, 44 cases of treated medullary carcinoma of thyroid were retrospectively reviewed in Government General Hospital, Chennai between 1987 and 2002. Patients who underwent total thyroidectomy with only central compartment dissection were compared with those who had undergone total thyroidectomy with meticulous triple compartment (bilateral lateral and central groups) nodal dissection. The group of total thyroidectomy with only central compartment dissection had high rate of lymph nodal recurrence and persistent hypercalcitoninaemia when compared with the group of total thyroidectomy with meticulous triple compartment nodal dissection. (Chi square value 4.503 with p<0.05).

  4. Simple vector bundles on a nodal Weierstrass cubic and quasi-trigonometric solutions of the classical Yang-Baxter equation

    NASA Astrophysics Data System (ADS)

    Burban, Igor; Galinat, Lennart; Stolin, Alexander

    2017-11-01

    In this paper we study the combinatorics of quasi-trigonometric solutions of the classical Yang-Baxter equation, arising from simple vector bundles on a nodal Weierstraß cubic. Dedicated to the memory of Petr Petrovich Kulish.

  5. Analysis of nodal aberration properties in off-axis freeform system design.

    PubMed

    Shi, Haodong; Jiang, Huilin; Zhang, Xin; Wang, Chao; Liu, Tao

    2016-08-20

    Freeform surfaces have the advantage of balancing off-axis aberration. In this paper, based on the framework of nodal aberration theory (NAT) applied to the coaxial system, the third-order astigmatism and coma wave aberration expressions of an off-axis system with Zernike polynomial surfaces are derived. The relationship between the off-axis and surface shape acting on the nodal distributions is revealed. The nodal aberration properties of the off-axis freeform system are analyzed and validated by using full-field displays (FFDs). It has been demonstrated that adding Zernike terms, up to nine, to the off-axis system modifies the nodal locations, but the field dependence of the third-order aberration does not change. On this basis, an off-axis two-mirror freeform system with 500 mm effective focal length (EFL) and 300 mm entrance pupil diameter (EPD) working in long-wave infrared is designed. The field constant aberrations induced by surface tilting are corrected by selecting specific Zernike terms. The design results show that the nodes of third-order astigmatism and coma move back into the field of view (FOV). The modulation transfer function (MTF) curves are above 0.4 at 20 line pairs per millimeter (lp/mm) which meets the infrared reconnaissance requirement. This work provides essential insight and guidance for aberration correction in off-axis freeform system design.

  6. Conserved and divergent expression patterns of markers of axial development in the laboratory opossum, Monodelphis domestica.

    PubMed

    Yoshida, Michio; Kajikawa, Eriko; Yamamoto, Daisuke; Kurokawa, Daisuke; Yonemura, Shigenobu; Kobayashi, Kensaku; Kiyonari, Hiroshi; Aizawa, Shinichi

    2016-12-01

    Previous comparative studies suggest that the requirement for Nodal in epiblast and hypoblast development is unique to mammalians. Expression of anterior visceral endoderm (AVE) genes in the visceral endoderm and of their orthologs in the hypoblast may be unique to mammalians and avians, and is absent in the reptilian hypoblast. Axis formation in reptiles is signaled by the formation of the posterior marginal epiblast (PME), which expresses a series of primitive streak genes. To assess the phylogenetic origin of Nodal and AVE gene expression and axis formation in amniotes, we examined marker gene expression in gray short-tailed opossum, a metatherian. Nodal was expressed in neither epiblast nor hypoblast of opossum embryos. No AVE genes were expressed in the opossum hypoblast. Attainment of polarity in the embryonic disk was signaled by Nodal, Wnt3a, Fgf8, and Bra expression in the PME at 8.5 days post-coitus. Nodal expression in epiblast or hypoblast may be unique to eutherians. AVE gene expression in visceral endoderm and hypoblast may have been independently acquired in eutherian and avian lineages. PME formation appears to be the event that signals axis formation in reptilian and metatherian embryos, and thus may be an ancestral characteristic of basal amniotes. Developmental Dynamics 245:1176-1188, 2016. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  7. Is uniportal thoracoscopic surgery a feasible approach for advanced stages of non-small cell lung cancer?

    PubMed Central

    Fieira, Eva; Delgado, Maria; Mendez, Lucía; Fernandez, Ricardo; de la Torre, Mercedes

    2014-01-01

    Objectives Conventional video-assisted thoracoscopic (VATS) lobectomy for advanced lung cancer is a feasible and safe surgery in experienced centers. The aim of this study is to assess the feasibility of uniportal VATS approach in the treatment of advanced non-small cell lung cancer (NSCLC) and compare the perioperative outcomes and survival with those in early-stage tumors operated through the uniportal approach. Methods From June 2010 to December 2012, we performed 163 uniportal VATS major pulmonary resections. Only NSCLC cases were included in this study (130 cases). Patients were divided into two groups: (A) early stage and (B) advanced cases (>5 cm, T3 or T4, or tumors requiring neoadjuvant treatment). A descriptive and retrospective study was performed, comparing perioperative outcomes and survival obtained in both groups. A survival analysis was performed with Kaplan-Meier curves and the log-rank test was used to compare survival between patients with early and advanced stages. Results A total of 130 cases were included in the study: 87 (A) vs. 43 (B) patients (conversion rate 1.1 vs. 6.5%, P=0.119). Mean global age was 64.9 years and 73.8% were men. The patient demographic data was similar in both groups. Upper lobectomies (A, 52 vs. B, 21 patients) and anatomic segmentectomies (A, 4 vs. B, 0) were more frequent in group A while pneumonectomy was more frequent in B (A, 1 vs. B, 6 patients). Surgical time was longer (144.9±41.3 vs. 183.2±48.9, P<0.001), and median number of lymph nodes (14 vs. 16, P=0.004) were statistically higher in advanced cases. Median number of nodal stations (5 vs. 5, P=0.165), days of chest tube (2 vs. 2, P=0.098), HOS (3 vs. 3, P=0.072), and rate of complications (17.2% vs. 14%, P=0.075) were similar in both groups. One patient died on the 58th postoperative day. The 30-month survival rate was 90% for the early stage group and 74% for advanced cases Conclusions Uniportal VATS lobectomy for advanced cases of NSCLC is a safe and reliable procedure that provides perioperative outcomes similar to those obtained in early stage tumours operated through this same technique. Further long term survival analyses are ongoing on a large number of patients. PMID:24976985

  8. PATRAN-STAGS translator (PATSTAGS)

    NASA Technical Reports Server (NTRS)

    Otte, Neil

    1990-01-01

    A a computer program used to translate PATRAN finite element model data into Structural Analysis of General Shells (STAGS) input data is presented. The program supports translation of nodal, nodal constraints, element, force, and pressure data. The subroutine UPRESS required for the readings of live pressure data into STAGS is also presented.

  9. All row, planar fault detection system

    DOEpatents

    Archer, Charles Jens; Pinnow, Kurt Walter; Ratterman, Joseph D; Smith, Brian Edward

    2013-07-23

    An apparatus, program product and method for detecting nodal faults may simultaneously cause designated nodes of a cell to communicate with all nodes adjacent to each of the designated nodes. Furthermore, all nodes along the axes of the designated nodes are made to communicate with their adjacent nodes, and the communications are analyzed to determine if a node or connection is faulty.

  10. A Simple Dissection Method for the Conduction System of the Human Heart

    ERIC Educational Resources Information Center

    Yanagawa, Nariaki; Nakajima, Yuji

    2009-01-01

    A simple dissection guide for the conduction system of the human heart is shown. The atrioventricular (AV) node, AV bundle, and right bundle branch were identified in a formaldehyde-fixed human heart. The sinu-atrial (SA) node could not be found, but the region in which SA node was contained was identified using the SA nodal artery. Gross…

  11. The Time Line and the "Why Now?" Question: A Technique and Rationale for Therapy, Training, Organizational Consultation and Research.

    ERIC Educational Resources Information Center

    Stanton, M. Duncan

    1992-01-01

    Presents method for quickly and graphically clarifying relationship between life cycle events and the onset of problems in families. Describes how to laterally organize events in terms of points in time at which they occurred and explains structural version, expressed into formats, that elucidates interaction between nodal events and changes in…

  12. Convergence and divergence across construction methods for human brain white matter networks: an assessment based on individual differences.

    PubMed

    Zhong, Suyu; He, Yong; Gong, Gaolang

    2015-05-01

    Using diffusion MRI, a number of studies have investigated the properties of whole-brain white matter (WM) networks with differing network construction methods (node/edge definition). However, how the construction methods affect individual differences of WM networks and, particularly, if distinct methods can provide convergent or divergent patterns of individual differences remain largely unknown. Here, we applied 10 frequently used methods to construct whole-brain WM networks in a healthy young adult population (57 subjects), which involves two node definitions (low-resolution and high-resolution) and five edge definitions (binary, FA weighted, fiber-density weighted, length-corrected fiber-density weighted, and connectivity-probability weighted). For these WM networks, individual differences were systematically analyzed in three network aspects: (1) a spatial pattern of WM connections, (2) a spatial pattern of nodal efficiency, and (3) network global and local efficiencies. Intriguingly, we found that some of the network construction methods converged in terms of individual difference patterns, but diverged with other methods. Furthermore, the convergence/divergence between methods differed among network properties that were adopted to assess individual differences. Particularly, high-resolution WM networks with differing edge definitions showed convergent individual differences in the spatial pattern of both WM connections and nodal efficiency. For the network global and local efficiencies, low-resolution and high-resolution WM networks for most edge definitions consistently exhibited a highly convergent pattern in individual differences. Finally, the test-retest analysis revealed a decent temporal reproducibility for the patterns of between-method convergence/divergence. Together, the results of the present study demonstrated a measure-dependent effect of network construction methods on the individual difference of WM network properties. © 2015 Wiley Periodicals, Inc.

  13. An Improved Micropropagation Protocol by Ex Vitro Rooting of Passiflora edulis Sims. f. flavicarpa Deg. through Nodal Segment Culture.

    PubMed

    Shekhawat, Mahipal S; Manokari, M; Ravindran, C P

    2015-01-01

    A procedure for rapid clonal propagation of Passiflora edulis Sims. f. flavicarpa Deg. (Passifloraceae) has been developed in this study. Nodal explants were sterilized with 0.1% HgCl2 and inoculated on Murashige and Skoog (MS) basal medium. The addition of 2.0 mgL(-1) 6-benzylaminopurine (BAP) to MS medium caused an extensive proliferation of multiple shoots (8.21 ± 1.13) primordial from the nodal meristems. Subculturing of these multiple shoots on the MS medium augmented with 1.0 mgL(-1) of each BAP and Kinetin (Kin) was successful for the multiplication of the shoots in vitro with maximum numbers of shoots (25.73 ± 0.06) within four weeks of incubation. Shoots were rooted best (7.13 ± 0.56 roots/shoots) on half strength MS medium supplemented with 2.0 mgL(-1) indole-3 butyric acid (IBA). All in vitro regenerated shoots were rooted by ex vitro method, and this has achieved 6-7 roots per shoot by pulsing of cut ends of the shoots using 200 as well as 300 mgL(-1) IBA. The plantlets were hardened in the greenhouse for 4-5 weeks. The hardened plantlets were shifted to manure containing nursery polybags after five weeks and then transferred to a sand bed for another four weeks for acclimatization before field planting with 88% survival rate.

  14. An Improved Micropropagation Protocol by Ex Vitro Rooting of Passiflora edulis Sims. f. flavicarpa Deg. through Nodal Segment Culture

    PubMed Central

    Shekhawat, Mahipal S.; Manokari, M.; Ravindran, C. P.

    2015-01-01

    A procedure for rapid clonal propagation of Passiflora edulis Sims. f. flavicarpa Deg. (Passifloraceae) has been developed in this study. Nodal explants were sterilized with 0.1% HgCl2 and inoculated on Murashige and Skoog (MS) basal medium. The addition of 2.0 mgL−1 6-benzylaminopurine (BAP) to MS medium caused an extensive proliferation of multiple shoots (8.21 ± 1.13) primordial from the nodal meristems. Subculturing of these multiple shoots on the MS medium augmented with 1.0 mgL−1 of each BAP and Kinetin (Kin) was successful for the multiplication of the shoots in vitro with maximum numbers of shoots (25.73 ± 0.06) within four weeks of incubation. Shoots were rooted best (7.13 ± 0.56 roots/shoots) on half strength MS medium supplemented with 2.0 mgL−1 indole-3 butyric acid (IBA). All in vitro regenerated shoots were rooted by ex vitro method, and this has achieved 6-7 roots per shoot by pulsing of cut ends of the shoots using 200 as well as 300 mgL−1 IBA. The plantlets were hardened in the greenhouse for 4-5 weeks. The hardened plantlets were shifted to manure containing nursery polybags after five weeks and then transferred to a sand bed for another four weeks for acclimatization before field planting with 88% survival rate. PMID:26273489

  15. [Study on Abnormal Topological Properties of Structural Brain Networks of Patients with Depression Comorbid with Anxiety].

    PubMed

    Wu, Xiuyong; Wu, Xiaoming; Peng, Hongjun; Ning, Yuping; Wu, Kai

    2016-06-01

    This paper is aimed to analyze the topological properties of structural brain networks in depressive patients with and without anxiety and to explore the neuropath logical mechanisms of depression comorbid with anxiety.Diffusion tensor imaging and deterministic tractography were applied to map the white matter structural networks.We collected 20 depressive patients with anxiety(DPA),18 depressive patients without anxiety(DP),and 28 normal controls(NC)as comparative groups.The global and nodal properties of the structural brain networks in the three groups were analyzed with graph theoretical methods.The result showed that1 the structural brain networks in three groups showed small-world properties and highly connected global hubs predominately from association cortices;2DP group showed lower local efficiency and global efficiency compared to NC group,whereas DPA group showed higher local efficiency and global efficiency compared to NC group;3significant differences of network properties(clustering coefficient,characteristic path lengths,local efficiency,global efficiency)were found between DPA and DP groups;4DP group showed significant changes of nodal efficiency in the brain areas primarily in the temporal lobe and bilateral frontal gyrus,compared to DPA and NC groups.The analysis indicated that the DP and DPA groups showed nodal properties of the structural brain networks,compared to NC group.Moreover,the two diseased groups indicated an opposite trend in the network properties.The results of this study may provide a new imaging index for clinical diagnosis for depression comorbid with anxiety.

  16. Machine learning classifier using abnormal brain network topological metrics in major depressive disorder.

    PubMed

    Guo, Hao; Cao, Xiaohua; Liu, Zhifen; Li, Haifang; Chen, Junjie; Zhang, Kerang

    2012-12-05

    Resting state functional brain networks have been widely studied in brain disease research. However, it is currently unclear whether abnormal resting state functional brain network metrics can be used with machine learning for the classification of brain diseases. Resting state functional brain networks were constructed for 28 healthy controls and 38 major depressive disorder patients by thresholding partial correlation matrices of 90 regions. Three nodal metrics were calculated using graph theory-based approaches. Nonparametric permutation tests were then used for group comparisons of topological metrics, which were used as classified features in six different algorithms. We used statistical significance as the threshold for selecting features and measured the accuracies of six classifiers with different number of features. A sensitivity analysis method was used to evaluate the importance of different features. The result indicated that some of the regions exhibited significantly abnormal nodal centralities, including the limbic system, basal ganglia, medial temporal, and prefrontal regions. Support vector machine with radial basis kernel function algorithm and neural network algorithm exhibited the highest average accuracy (79.27 and 78.22%, respectively) with 28 features (P<0.05). Correlation analysis between feature importance and the statistical significance of metrics was investigated, and the results revealed a strong positive correlation between them. Overall, the current study demonstrated that major depressive disorder is associated with abnormal functional brain network topological metrics and statistically significant nodal metrics can be successfully used for feature selection in classification algorithms.

  17. Functional Connectivity Changes in Resting-State EEG as Potential Biomarker for Amyotrophic Lateral Sclerosis.

    PubMed

    Iyer, Parameswaran Mahadeva; Egan, Catriona; Pinto-Grau, Marta; Burke, Tom; Elamin, Marwa; Nasseroleslami, Bahman; Pender, Niall; Lalor, Edmund C; Hardiman, Orla

    2015-01-01

    Amyotrophic Lateral Sclerosis (ALS) is heterogeneous and overlaps with frontotemporal dementia. Spectral EEG can predict damage in structural and functional networks in frontotemporal dementia but has never been applied to ALS. 18 incident ALS patients with normal cognition and 17 age matched controls underwent 128 channel EEG and neuropsychology assessment. The EEG data was analyzed using FieldTrip software in MATLAB to calculate simple connectivity measures and scalp network measures. sLORETA was used in nodal analysis for source localization and same methods were applied as above to calculate nodal network measures. Graph theory measures were used to assess network integrity. Cross spectral density in alpha band was higher in patients. In ALS patients, increased degree values of the network nodes was noted in the central and frontal regions in the theta band across seven of the different connectivity maps (p<0.0005). Among patients, clustering coefficient in alpha and gamma bands was increased in all regions of the scalp and connectivity were significantly increased (p=0.02). Nodal network showed increased assortativity in alpha band in the patients group. The Clustering Coefficient in Partial Directed Connectivity (PDC) showed significantly higher values for patients in alpha, beta, gamma, theta and delta frequencies (p=0.05). There is increased connectivity in the fronto-central regions of the scalp and areas corresponding to Salience and Default Mode network in ALS, suggesting a pathologic disruption of neuronal networking in early disease states. Spectral EEG has potential utility as a biomarker in ALS.

  18. Defining the Risk of Involvement for Each Neck Nodal Level in Patients With Early T-Stage Node-Positive Oropharyngeal Carcinoma

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sanguineti, Giuseppe; Califano, Joseph; Stafford, Edward

    Purpose: To assess the risk of ipsilateral subclinical neck nodal involvement for early T-stage/node-positive oropharyngeal squamous cell carcinoma. Methods and Materials: Patients undergoing multilevel upfront neck dissection (ND) at Johns Hopkins Hospital within the last 10 years for early clinical T-stage (cT1-2) node-positive (cN+) oropharyngeal squamous cell carcinoma were identified. Pathologic involvement of Levels IB-V was determined. For each nodal level, the negative predictive value of imaging results was computed by using sensitivity/specificity data for computed tomography (CT). This was used to calculate 1 - negative predictive value, or the risk that a negative level on CT harbors subclinical disease.more » Results: One hundred three patients met the criteria. Radical ND was performed in 14.6%; modified radical ND, in 70.9%; and selective ND, in 14.6%. Pathologic positivity rates were 9.5%, 91.3%, 40.8%, 18.0%, and 3.3% for Levels IB-V, respectively. Risks of subclinical disease despite negative CT imaging results were calculated as 3.1%, 76.3%, 17.5%, 6.3%, and 1.0% for Levels IB-V, respectively. Conclusions: Levels IB and V are at very low (<5%) risk of involvement, even with ipsilateral to pathologically proven neck disease; this can guide radiation planning. Levels II and III should be included in high-risk volumes regardless of imaging results, and Level IV should be included within the lowest risk volume.« less

  19. Flowfield-Dependent Mixed Explicit-Implicit (FDMEL) Algorithm for Computational Fluid Dynamics

    NASA Technical Reports Server (NTRS)

    Garcia, S. M.; Chung, T. J.

    1997-01-01

    Despite significant achievements in computational fluid dynamics, there still remain many fluid flow phenomena not well understood. For example, the prediction of temperature distributions is inaccurate when temperature gradients are high, particularly in shock wave turbulent boundary layer interactions close to the wall. Complexities of fluid flow phenomena include transition to turbulence, relaminarization separated flows, transition between viscous and inviscid incompressible and compressible flows, among others, in all speed regimes. The purpose of this paper is to introduce a new approach, called the Flowfield-Dependent Mixed Explicit-Implicit (FDMEI) method, in an attempt to resolve these difficult issues in Computational Fluid Dynamics (CFD). In this process, a total of six implicitness parameters characteristic of the current flowfield are introduced. They are calculated from the current flowfield or changes of Mach numbers, Reynolds numbers, Peclet numbers, and Damkoehler numbers (if reacting) at each nodal point and time step. This implies that every nodal point or element is provided with different or unique numerical scheme according to their current flowfield situations, whether compressible, incompressible, viscous, inviscid, laminar, turbulent, reacting, or nonreacting. In this procedure, discontinuities or fluctuations of an variables between adjacent nodal points are determined accurately. If these implicitness parameters are fixed to certain numbers instead of being calculated from the flowfield information, then practically all currently available schemes of finite differences or finite elements arise as special cases. Some benchmark problems to be presented in this paper will show the validity, accuracy, and efficiency of the proposed methodology.

  20. The 13 January 2001 El Salvador earthquake: A multidata analysis

    NASA Astrophysics Data System (ADS)

    ValléE, Martin; Bouchon, Michel; Schwartz, Susan Y.

    2003-04-01

    On 13 January 2001, a large normal faulting intermediate depth event (Mw = 7.7) occurred 40 km off the El Salvadorian coast (Central America). We analyze this earthquake using teleseismic, regional, and local data. We first build a kinematic source model by simultaneously inverting P and SH displacement waveforms and source time functions derived from surface waves using an empirical Green's function analysis. In an attempt to discriminate between the two nodal planes (30° trenchward dipping and 60° landward dipping), we perform identical inversions using both possible fault planes. After relocating the hypocentral depth at 54 km, we retrieve the kinematic features of the rupture using a combination of the Neighborhood algorithm of [1999] and the Simplex method allowing for variable rupture velocity and slip. We find updip rupture propagation yielding a centroid depth around 47 km for both assumed fault planes with a larger variance reduction obtained using the 60° landward dipping nodal plane. We test the two possible fault models using regional broadband data and near-field accelerograms provided by [2001]. Near-field data confirm that the steeper landward dipping nodal plane is preferred. Rupture propagated mostly updip and to the northwest, resulting in a main moment release zone of approximately 25 km × 50 km with an average slip of ˜3.5 m. The large slip occurs near the interplate interface at a location where the slab steepens dip significantly. The occurrence of this event is well-explained by bending of the subducting plate.

  1. Performance of endoscopic ultrasound in staging rectal adenocarcinoma appropriate for primary surgical resection.

    PubMed

    Ahuja, Nitin K; Sauer, Bryan G; Wang, Andrew Y; White, Grace E; Zabolotsky, Andrew; Koons, Ann; Leung, Wesley; Sarkaria, Savreet; Kahaleh, Michel; Waxman, Irving; Siddiqui, Ali A; Shami, Vanessa M

    2015-02-01

    Endoscopic ultrasound (EUS) often is used to stage rectal cancer and thereby guide treatment. Prior assessments of its accuracy have been limited by small sets of data collected from tumors of varying stages. We aimed to characterize the diagnostic performance of EUS analysis of rectal cancer, paying particular attention to determining whether patients should undergo primary surgical resection. We performed a retrospective observational study using procedural databases and electronic medical records from 4 academic tertiary-care hospitals, collecting data on EUS analyses from 2000 through 2012. Data were analyzed from 86 patients with rectal cancer initially staged as T2N0 by EUS. The negative predictive value (NPV) was calculated by comparing initial stages determined by EUS with those determined by pathology analysis of surgical samples. Logistic regression models were used to assess variation in diagnostic performance with case attributes. EUS excluded advanced tumor depth with an NPV of 0.837 (95% confidence interval [CI], 0.742-0.908), nodal metastasis with an NPV of 0.872 (95% CI, 0.783-0.934), and both together with an NPV of 0.767 (95% CI, 0.664-0.852) compared with pathology analysis. Incorrect staging by EUS affected treatment decision making for 20 of 86 patients (23.3%). Patient age at time of the procedure correlated with the NPV for metastasis to lymph node, but no other patient features were associated significantly with diagnostic performance. Based on a multicenter retrospective study, EUS staging of rectal cancer as T2N0 excludes advanced tumor depth and nodal metastasis, respectively, with an approximate NPV of 85%, similar to that of other modalities. EUS has an error rate of approximately 23% in identifying disease appropriate for surgical resection, which is lower than previously reported. Copyright © 2015 AGA Institute. Published by Elsevier Inc. All rights reserved.

  2. IMRT and 3D conformal radiotherapy with or without elective nodal irradiation in locally advanced NSCLC: A direct comparison of PET-based treatment planning.

    PubMed

    Fleckenstein, Jochen; Kremp, Katharina; Kremp, Stephanie; Palm, Jan; Rübe, Christian

    2016-02-01

    The potential of intensity-modulated radiation therapy (IMRT) as opposed to three-dimensional conformal radiotherapy (3D-CRT) is analyzed for two different concepts of fluorodeoxyglucose positron emission tomography (FDG PET)-based target volume delineation in locally advanced non-small cell lung cancer (LA-NSCLC): involved-field radiotherapy (IF-RT) vs. elective nodal irradiation (ENI). Treatment planning was performed for 41 patients with LA-NSCLC, using four different planning approaches (3D-CRT-IF, 3D-CRT-ENI, IMRT-IF, IMRT-ENI). ENI included a boost irradiation after 50 Gy. For each plan, maximum dose escalation was calculated based on prespecified normal tissue constraints. The maximum prescription dose (PD), tumor control probability (TCP), conformal indices (CI), and normal tissue complication probabilities (NTCP) were analyzed. IMRT resulted in statistically significant higher prescription doses for both target volume concepts as compared with 3D-CRT (ENI: 68.4 vs. 60.9 Gy, p < 0.001; IF: 74.3 vs. 70.1 Gy, p < 0.03). With IMRT-IF, a PD of at least 66 Gy was achieved for 95 % of all plans. For IF as compared with ENI, there was a considerable theoretical increase in TCP (IMRT: 27.3 vs. 17.7 %, p < 0.00001; 3D-CRT: 20.2 vs. 9.9 %, p < 0.00001). The esophageal NTCP showed a particularly good sparing with IMRT vs. 3D-CRT (ENI: 12.3 vs. 30.9 % p < 0.0001; IF: 15.9 vs. 24.1 %; p < 0.001). The IMRT technique and IF target volume delineation allow a significant dose escalation and an increase in TCP. IMRT results in an improved sparing of OARs as compared with 3D-CRT at equivalent dose levels.

  3. A System Approach to Navy Medical Education and Training. Appendix 36. Competency Curriculum for Operating Room Assistant and Operating Room Technician.

    DTIC Science & Technology

    1974-08-31

    These methods and curriculum materials constituted a third (instructional) sub-system. Thus, as originally proposed, a system capability has been...NODAL and its associated indexing techniques, it is possible to assemble modified or completely different inventories than those used in this research...covering all hair as a source of infection Method by which synthetic material causes static electricity Danger of static electricity in O.R. suite I

  4. COMPLEX VARIABLE BOUNDARY ELEMENT METHOD: APPLICATIONS.

    USGS Publications Warehouse

    Hromadka, T.V.; Yen, C.C.; Guymon, G.L.

    1985-01-01

    The complex variable boundary element method (CVBEM) is used to approximate several potential problems where analytical solutions are known. A modeling result produced from the CVBEM is a measure of relative error in matching the known boundary condition values of the problem. A CVBEM error-reduction algorithm is used to reduce the relative error of the approximation by adding nodal points in boundary regions where error is large. From the test problems, overall error is reduced significantly by utilizing the adaptive integration algorithm.

  5. Performance of a recoverable tug for planetary missions including use of perigee propulsion and corrections for nodal regression

    NASA Technical Reports Server (NTRS)

    Borsody, J.

    1976-01-01

    Mathematical equations are derived by using the Maximum Principle to obtain the maximum payload capability of a reusable tug for planetary missions. The mathematical formulation includes correction for nodal precession of the space shuttle orbit. The tug performs this nodal correction in returning to this precessed orbit. The sample case analyzed represents an inner planet mission as defined by the declination (fixed) and right ascension of the outgoing asymptote and the mission energy. Payload capability is derived for a typical cryogenic tug and the sample case with and without perigee propulsion. Optimal trajectory profiles and some important orbital elements are also discussed.

  6. Locational Marginal Pricing in the Campus Power System at the Power Distribution Level

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hao, Jun; Gu, Yi; Zhang, Yingchen

    2016-11-14

    In the development of smart grid at distribution level, the realization of real-time nodal pricing is one of the key challenges. The research work in this paper implements and studies the methodology of locational marginal pricing at distribution level based on a real-world distribution power system. The pricing mechanism utilizes optimal power flow to calculate the corresponding distributional nodal prices. Both Direct Current Optimal Power Flow and Alternate Current Optimal Power Flow are utilized to calculate and analyze the nodal prices. The University of Denver campus power grid is used as the power distribution system test bed to demonstrate themore » pricing methodology.« less

  7. “Nodal Gap” induced by the incommensurate diagonal spin density modulation in underdoped high- T c superconductors

    DOE PAGES

    Zhou, Tao; Gao, Yi; Zhu, Jian -Xin

    2015-03-07

    Recenmore » tly it was revealed that the whole Fermi surface is fully gapped for several families of underdoped cuprates. The existence of the finite energy gap along the d -wave nodal lines (nodal gap) contrasts the common understanding of the d -wave pairing symmetry, which challenges the present theories for the high- T c superconductors. Here we propose that the incommensurate diagonal spin-density-wave order can account for the above experimental observation. The Fermi surface and the local density of states are also studied. Our results are in good agreement with many important experiments in high- T c superconductors.« less

  8. Pathology of nodal marginal zone lymphomas.

    PubMed

    Pileri, Stefano; Ponzoni, Maurilio

    Nodal marginal zone B cell lymphomas (NMZLs) are a rare group of lymphoid disorders part of the spectrum of marginal zone B-cell lymphomas, which encompass splenic marginal one B-cell lymphoma (SMZL) and extra nodal marginal zone of B-cell lymphoma (EMZL), often of MALT-type. Two clinicopathological forms of NMZL are recognized: adult-type and pediatric-type, respectively. NMZLs show overlapping features with other types of MZ, but distinctive features as well. In this review, we will focus on the salient distinguishing features of NMZL mostly under morphological/immunophenotypical/molecular perspectives in views of the recent acquisitions and forthcoming updated 2016 WHO classification of lymphoid malignancies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Off-diagonal Jacobian support for Nodal BCs

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Peterson, John W.; Andrs, David; Gaston, Derek R.

    In this brief note, we describe the implementation of o-diagonal Jacobian computations for nodal boundary conditions in the Multiphysics Object Oriented Simulation Environment (MOOSE) [1] framework. There are presently a number of applications [2{5] based on the MOOSE framework that solve complicated physical systems of partial dierential equations whose boundary conditions are often highly nonlinear. Accurately computing the on- and o-diagonal Jacobian and preconditioner entries associated to these constraints is crucial for enabling ecient numerical solvers in these applications. Two key ingredients are required for properly specifying the Jacobian contributions of nonlinear nodal boundary conditions in MOOSE and nite elementmore » codes in general: 1. The ability to zero out entire Jacobian matrix rows after \

  10. Symmorphic Intersecting Nodal Rings in Semiconducting Layers

    NASA Astrophysics Data System (ADS)

    Gong, Cheng; Xie, Yuee; Chen, Yuanping; Kim, Heung-Sik; Vanderbilt, David

    2018-03-01

    The unique properties of topological semimetals have strongly driven efforts to seek for new topological phases and related materials. Here, we identify a critical condition for the existence of intersecting nodal rings (INRs) in symmorphic crystals, and further classify all possible kinds of INRs which can be obtained in the layered semiconductors with Amm2 and Cmmm space group symmetries. Several honeycomb structures are suggested to be topological INR semimetals, including layered and "hidden" layered structures. Transitions between the three types of INRs, named as α , β , and γ type, can be driven by external strains in these structures. The resulting surface states and Landau-level structures, more complicated than those resulting from a simple nodal loop, are also discussed.

  11. In Papillary Thyroid Cancer, Preoperative Central Neck Ultrasound Detects Only Macroscopic Surgical Disease, But Negative Findings Predict Excellent Long-Term Regional Control and Survival

    PubMed Central

    Moreno, Mauricio A.; Edeiken-Monroe, Beth S.; Siegel, Eric R.; Sherman, Steven I.

    2012-01-01

    Background Ultrasound (US) of the central neck compartment (CNC) is considered of limited sensitivity for nodal spread in papillary thyroid cancer (PTC); elective neck dissection is commonly advocated even in the absence of sonographic abnormalities. We hypothesized that US is an accurate predictor for long-term disease-free survival, regardless of the use of elective central neck dissection in patients with PTC. Methods A retrospective chart review of 331 consecutive PTC patients treated with total thyroidectomy at M.D. Anderson Cancer Center between 1996 and 2003 was performed. Information retrieved included preoperative sonographic status of the CNC, surgical treatment of the neck, demographics, cancer staging, histopathological variables and use of adjuvant treatment. The endpoints for the study were nodal recurrence and survival. Results There were 112 males and 219 females with a median age of 44 years (range 11–87). The median follow-up time for the series was 71.5 months (range 12.7–148.7). There were 151 (45.6%) patients with a T1, 58 (17.5%) with a T2, 70 (21.1%) with a T3, and 52 (15.7%) with a T4. Preoperative sonographic abnormalities were present in the CNC in 79 (23.9%) patients. During the surveillance period, 11 (3.2%) patients recurred in the central neck, with an average time for recurrence of 22.8 months. Advanced T stage (T3/T4) and abnormal US were independent prognostic factors for recurrence in the central neck (p=0.013 and p=0.005 respectively). There were 119 (35%) patients with a sonographically negative central compartment who underwent elective central neck dissection; 85 of them (71.4%) were found to be histopathologically N(+) while 34 (28.6%) were pN0. There were no differences in overall survival (p=0.32), disease specific survival (DSS; p=0.49), and recurrence-free survival (p=0.32) between these two groups. Preoperative US of the CNC was an age-independent predictor for overall survival (p<0.001), DSS (p=0.0097), and disease-free survival (p=0.0005) on bivariate Cox regression. Conclusions US of the central compartment is an age-independent predictor for survival and CNC recurrence-free survival in PTC. Prophylactic neck dissection of the central compartment does not improve long-term disease control, regardless of the histopathological status of the lymph nodes retrieved. Our findings emphasize the ability of US to clinically detect relevant nodal disease and support conservative management of the CNC in the absence of abnormal findings. PMID:22280230

  12. Experimental Influence Coefficients and Vibration Modes

    NASA Technical Reports Server (NTRS)

    Weidman, Deene J.; Kordes, Eldon E.

    1959-01-01

    Test results are presented for both symmetrical and antisymmetrical static loading of a wing model mounted on a three-point support system. The first six free-free vibration modes were determined experimentally. A comparison is made of the symmetrical nodal patterns and frequencies with the symmetrical nodal patterns and frequencies calculated from the experimental influence coefficients.

  13. PATSTAGS: PATRAN-To-STAGSC-1 Translator

    NASA Technical Reports Server (NTRS)

    Otte, Neil

    1993-01-01

    PATSTAGS computer program translates data from PATRAN finite-element mathematical model into STAGS input records used for engineering analysis. Reads data from PATRAN neutral file and writes STAGS input records into STAGS input file and UPRESS data file. Supports translations of nodal constraints, and of nodal, element, force, and pressure data. Written in FORTRAN 77.

  14. Contribution of Hedgehog signaling to the establishment of left-right asymmetry in the sea urchin

    PubMed Central

    Warner, Jacob F.; Miranda, Esther L.; McClay, David R.

    2016-01-01

    Summary Most bilaterians exhibit a left-right asymmetric distribution of their internal organs. The sea urchin larva is notable in this regard since most adult structures are generated from left sided embryonic structures. The gene regulatory network governing this larval asymmetry is still a work in progress but involves several conserved signaling pathways including Nodal, and BMP. Here we provide a comprehensive analysis of Hedgehog signaling and it’s contribution to left-right asymmetry. We report that Hh signaling plays a conserved role to regulate late asymmetric expression of Nodal and that this regulation occurs after Nodal breaks left-right symmetry in the mesoderm. Thus, while Hh functions to maintain late Nodal expression, the molecular asymmetry of the future coelomic pouches is locked in. Furthermore we report that cilia play a role only insofar as to transduce Hh signaling and do not have an independent effect on the asymmetry of the mesoderm. From this, we are able to construct a more complete regulatory network governing the establishment of left-right asymmetry in the sea urchin. PMID:26872875

  15. Contribution of hedgehog signaling to the establishment of left-right asymmetry in the sea urchin.

    PubMed

    Warner, Jacob F; Miranda, Esther L; McClay, David R

    2016-03-15

    Most bilaterians exhibit a left-right asymmetric distribution of their internal organs. The sea urchin larva is notable in this regard since most adult structures are generated from left sided embryonic structures. The gene regulatory network governing this larval asymmetry is still a work in progress but involves several conserved signaling pathways including Nodal, and BMP. Here we provide a comprehensive analysis of Hedgehog signaling and it's contribution to left-right asymmetry. We report that Hh signaling plays a conserved role to regulate late asymmetric expression of Nodal and that this regulation occurs after Nodal breaks left-right symmetry in the mesoderm. Thus, while Hh functions to maintain late Nodal expression, the molecular asymmetry of the future coelomic pouches is locked in. Furthermore we report that cilia play a role only insofar as to transduce Hh signaling and do not have an independent effect on the asymmetry of the mesoderm. From this, we are able to construct a more complete regulatory network governing the establishment of left-right asymmetry in the sea urchin. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. An efficient in vitro regeneration protocol for a natural dye yielding plant, Strobilanthes flaccidifolious Nees., from nodal explants.

    PubMed

    Deb, Chitta Ranjan; Arenmongla, T

    2012-11-01

    Adventitious shoot buds formation from axillary buds of nodal segments of S. flaccidifolious was achieved on MS medium containing sucrose (3%, w/v), and a-naphthalene acetic acid (NAA; 3 microM) and benzyl adenine (3 microM) in combination. The nodal segments were primed on 'Growtak Sieve' for 48 h on MS medium containing sucrose (2%), polyvinyl pyrollidone (200 mgL(-1)) as antioxidant. About 80% of primed nodal segments responded positively and formed approximately 12 adventitious shoot buds per explants from explants collected during October-November months of every year. The shoot buds converted into plantlets on MS medium containing sucrose (3%) and kinetin (3 microM) where approximately 7 micro shoots developed per subculture after 8 weeks of culture. The regenerated micro shoots induced average 14 roots/plant on medium containing NAA (3 microM). The regenerates were hardened for 6-7 weeks on medium with 1/2MS salt solution and sucrose (2%) under normal laboratory condition before transferring to potting mix. About 70% transplants survived after two months of transfer.

  17. Nodal to nodeless superconducting energy-gap structure change concomitant with Fermi-surface reconstruction in the heavy-fermion compound CeCoIn 5

    DOE PAGES

    Kim, Hyunsoo; Tanatar, M. A.; Flint, R.; ...

    2015-01-15

    The London penetration depth, λ(T), was measured in single crystals of Ce 1-xR xCoIn 5, R=La, Nd and Yb down to T min ≈ 50 mK (T c/T min ~50) using a tunnel-diode resonator. In the cleanest samples Δλ(T) is best described by the power law, Δλ(T) ∝ T n, with n ~ 1, consistent with line nodes. Substitutions of Ce with La, Nd and Yb lead to similar monotonic suppressions of T c, however the effects on Δλ(T) differ. While La and Nd dopings lead to increase of the exponent n and saturation at n ~ 2, as expectedmore » for a dirty nodal superconductor, Yb doping leads to n > 3, suggesting a change from nodal to nodeless superconductivity. As a result, this superconducting gap structure change happen in the same doping range where changes of the Fermi surface topology were reported, implying that the nodal structure and Fermi surface topology are closely linked.« less

  18. Serum decoy receptor 3 level: a predictive marker for nodal metastasis and survival among oral cavity cancer patients.

    PubMed

    Tu, Hsi-Feng; Liu, Chung-Ji; Liu, Shyun-Yeu; Chen, Yu-Ping; Yu, En-Hao; Lin, Shu-Chun; Chang, Kuo-Wei

    2011-03-01

    Validating markers for prediction of nodal metastasis could be beneficial in treatment of oral cavity cancer. Decoy receptor 3 (DcR3), locus on 20q13, functions as a death decoy inhibiting apoptosis mediated by the tumor necrosis factor receptor (TNFR) family. This study analyzed the serum level of DcR3 in relationship to the clinical parameters of oral cavity cancer patients together with detection of DcR3 genomic copy number in primary and recurrent tumors. Elevated serum DcR3 was associated with nodal metastasis and worse prognosis. Gain of DcR3 copy number was detected in 17% of primary tumor tissue but not found in healthy areca chewers. Tissue from recurrent tumors showed more frequent DcR3 copy number alteration (48%) than the paired primary tumor tissue. Serum DcR3 level is a predictor for the nodal metastasis and survival among oral cavity cancer patients and the DcR3 copy number alteration could underlie oral carcinogenesis progression. Copyright © 2010 Wiley Periodicals, Inc.

  19. Robustness Elasticity in Complex Networks

    PubMed Central

    Matisziw, Timothy C.; Grubesic, Tony H.; Guo, Junyu

    2012-01-01

    Network robustness refers to a network’s resilience to stress or damage. Given that most networks are inherently dynamic, with changing topology, loads, and operational states, their robustness is also likely subject to change. However, in most analyses of network structure, it is assumed that interaction among nodes has no effect on robustness. To investigate the hypothesis that network robustness is not sensitive or elastic to the level of interaction (or flow) among network nodes, this paper explores the impacts of network disruption, namely arc deletion, over a temporal sequence of observed nodal interactions for a large Internet backbone system. In particular, a mathematical programming approach is used to identify exact bounds on robustness to arc deletion for each epoch of nodal interaction. Elasticity of the identified bounds relative to the magnitude of arc deletion is assessed. Results indicate that system robustness can be highly elastic to spatial and temporal variations in nodal interactions within complex systems. Further, the presence of this elasticity provides evidence that a failure to account for nodal interaction can confound characterizations of complex networked systems. PMID:22808060

  20. In vitro clonal propagation of Achyranthes aspera L. and Achyranthes bidentata Blume using nodal explants.

    PubMed

    Gnanaraj, Wesely Edward; Antonisamy, Johnson Marimuthu; R B, Mohanamathi; Subramanian, Kavitha Marappampalyam

    2012-01-01

    To develop the reproducible in vitro propagation protocols for the medicinally important plants viz., Achyranthes aspera (A. aspera) L. and Achyranthes bidentata (A. bidentata) Blume using nodal segments as explants. Young shoots of A. aspera and A. bidentata were harvested and washed with running tap water and treated with 0.1% bavistin and rinsed twice with distilled water. Then the explants were surface sterilized with 0.1% (w/v) HgCl2 solutions for 1 min. After rinsing with sterile distilled water for 3-4 times, nodal segments were cut into smaller segments (1 cm) and used as the explants. The explants were placed horizontally as well as vertically on solid basal Murashige and Skoog (MS) medium supplemented with 3% sucrose, 0.6% (w/v) agar (Hi-Media, Mumbai) and different concentration and combination of 6-benzyl amino purine (BAP), kinetin (Kin), naphthalene acetic acid (NAA) and indole acetic acid (IAA) for direct regeneration. Adventitious proliferation was obtained from A. aspera and A. bidentata nodal segments inoculated on MS basal medium with 3% sucrose and augmented with BAP and Kin with varied frequency. MS medium augmented with 3.0 mg/L of BAP showed the highest percentage (93.60±0.71) of shootlets formation for A. aspera and (94.70±0.53) percentages for A. bidentata. Maximum number of shoots/explants (10.60±0.36) for A. aspera and (9.50±0.56) for A. bidentata was observed in MS medium fortified with 5.0 mg/L of BAP. For A. aspera, maximum mean length (5.50±0.34) of shootlets was obtained in MS medium augmented with 3.0 mg/L of Kin and for A. bidentata (5.40±0.61) was observed in the very same concentration. The highest percentage, maximum number of rootlets/shootlet and mean length of rootlets were observed in 1/2 MS medium supplemented with 1.0 mg/L of IBA. Seventy percentages of plants were successfully established in polycups. Sixty eight percentages of plants were well established in the green house condition. Sixty five percentages of plants were established in the field. The results have shown that use of nodal buds is an alternative reproducible and dependable method for clonal propagation of A. aspera and A. bidentata. The high rate of direct shoot-root multiplication and their high rate of post-hardening survival indicate that this protocol can be easily adopted for commercial large scale cultivation.

  1. Robotic salvage lymph node dissection for nodal-only recurrences after radical prostatectomy: Perioperative and early oncological outcomes.

    PubMed

    Linxweiler, Johannes; Saar, Matthias; Al-Kailani, Zaid; Janssen, Martin; Ezziddin, Samer; Stöckle, Michael; Siemer, Stefan; Ohlmann, Carsten-Henning

    2018-06-01

    Salvage lymph node dissection (sLND) - performed open or minimally-invasive - is a treatment modality that can be offered to patients with nodal recurrence after radical prostatectomy (RP), especially in times where modern imaging methods like choline- or PSMA-PET/CT are available. Yet, there are only very limited data on the safety and oncological effectiveness of robotic sLND. We retrospectively identified patients who underwent robotic sLND at our institution between 2013 and 2017 for nodal recurrence after RP, which had been diagnosed either by 18 F-choline- or 68 Ga-PSMA-PET/CT. We analyzed perioperative data and early oncological outcomes with a focus on the comparison of patients with preoperative choline- vs. those with preoperative PSMA-PET/CT. We identified 36 patients who underwent robotic sLND at a median time of 45.3 months [range 3.1;228.6] after RP, with nodal recurrences detected in 25 patients by PSMA- and in 11 by choline-PET/CT. Median preoperative PSA, operation time and blood loss were 1.98 ng/ml [range 0.09;35.15], 129.5 min [range 65;202] and 50 ml [range 0;400], respectively. No high-grade complications occurred. A median number of 6.5 [range 1;25] lymph nodes were removed with a median of 1 [range 0;9] tumor-occupied node. None of the patients received any adjuvant treatment. Median postoperative PSA-change was -57% [range -100; +58] in the PSMA- and +10% [range -91; +95] in the choline-group (p = 0.015). 44% of patients in the PSMA- and 18% of patients in the choline-group experienced complete biochemical response (cBCR; PSA <0.2 ng/ml). Median time from sLND to the initiation of further therapy was 12 months [range 2;21.5] in the PSMA-group and 4.7 months [range 2.2;18.9] in the choline-group (p = 0.001). This is the hitherto largest series on robotic sLND for nodal recurrence after RP. Robotic sLND is a feasible therapeutic option with low morbidity, which can at least delay the initiation of further therapy - in some patients up to several years. However, the extend of sLND has to be standardized and randomized trials are needed to finally define the oncological effectiveness of this approach. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. Path integral Monte Carlo and the electron gas

    NASA Astrophysics Data System (ADS)

    Brown, Ethan W.

    Path integral Monte Carlo is a proven method for accurately simulating quantum mechanical systems at finite-temperature. By stochastically sampling Feynman's path integral representation of the quantum many-body density matrix, path integral Monte Carlo includes non-perturbative effects like thermal fluctuations and particle correlations in a natural way. Over the past 30 years, path integral Monte Carlo has been successfully employed to study the low density electron gas, high-pressure hydrogen, and superfluid helium. For systems where the role of Fermi statistics is important, however, traditional path integral Monte Carlo simulations have an exponentially decreasing efficiency with decreased temperature and increased system size. In this thesis, we work towards improving this efficiency, both through approximate and exact methods, as specifically applied to the homogeneous electron gas. We begin with a brief overview of the current state of atomic simulations at finite-temperature before we delve into a pedagogical review of the path integral Monte Carlo method. We then spend some time discussing the one major issue preventing exact simulation of Fermi systems, the sign problem. Afterwards, we introduce a way to circumvent the sign problem in PIMC simulations through a fixed-node constraint. We then apply this method to the homogeneous electron gas at a large swatch of densities and temperatures in order to map out the warm-dense matter regime. The electron gas can be a representative model for a host of real systems, from simple medals to stellar interiors. However, its most common use is as input into density functional theory. To this end, we aim to build an accurate representation of the electron gas from the ground state to the classical limit and examine its use in finite-temperature density functional formulations. The latter half of this thesis focuses on possible routes beyond the fixed-node approximation. As a first step, we utilize the variational principle inherent in the path integral Monte Carlo method to optimize the nodal surface. By using a ansatz resembling a free particle density matrix, we make a unique connection between a nodal effective mass and the traditional effective mass of many-body quantum theory. We then propose and test several alternate nodal ansatzes and apply them to single atomic systems. Finally, we propose a method to tackle the sign problem head on, by leveraging the relatively simple structure of permutation space. Using this method, we find we can perform exact simulations this of the electron gas and 3He that were previously impossible.

  3. From cluster structures to nuclear molecules: The role of nodal structure of the single-particle wave functions

    NASA Astrophysics Data System (ADS)

    Afanasjev, A. V.; Abusara, H.

    2018-02-01

    The nodal structure of the density distributions of the single-particle states occupied in rod-shaped, hyper- and megadeformed structures of nonrotating and rotating N ˜Z nuclei has been investigated in detail. The single-particle states with the Nilsson quantum numbers of the [N N 0 ]1 /2 (with N from 0 to 5) and [N ,N -1 ,1 ]Ω (with N from 1 to 3 and Ω =1 /2 , 3/2) types are considered. These states are building blocks of extremely deformed shapes in the nuclei with mass numbers A ≤50 . Because of (near) axial symmetry and large elongation of such structures, the wave functions of the single-particle states occupied are dominated by a single basis state in cylindrical basis. This basis state defines the nodal structure of the single-particle density distribution. The nodal structure of the single-particle density distributions allows us to understand in a relatively simple way the necessary conditions for α clusterization and the suppression of the α clusterization with the increase of mass number. It also explains in a natural way the coexistence of ellipsoidal mean-field-type structures and nuclear molecules at similar excitation energies and the features of particle-hole excitations connecting these two types of the structures. Our analysis of the nodal structure of the single-particle density distributions does not support the existence of quantum liquid phase for the deformations and nuclei under study.

  4. Management of recurrent/persistent nodal disease in patients with differentiated thyroid cancer: a critical review of the risks and benefits of surgical intervention versus active surveillance.

    PubMed

    Tufano, Ralph P; Clayman, Gary; Heller, Keith S; Inabnet, William B; Kebebew, Electron; Shaha, Ashok; Steward, David L; Tuttle, R Michael

    2015-01-01

    The primary goals of this interdisciplinary consensus statement are to define the eligibility criteria for management of recurrent and persistent cervical nodal disease in patients with differentiated thyroid cancer (DTC) and to review the risks and benefits of surgical intervention versus active surveillance. A writing group was convened by the Surgical Affairs Committee of the American Thyroid Association and was tasked with identifying the important clinical elements to consider when managing recurrent/persistent nodal disease in patients with DTC based on the available evidence in the literature and the group's collective experience. The decision on how best to manage individual patients with suspected recurrent/persistent nodal disease is challenging and requires the consideration of a significant number of variables outlined by the members of the interdisciplinary team. Here we report on the consensus opinions that were reached by the writing group regarding the technical and clinical issues encountered in this patient population. Identification of recurrent/persistent disease requires a team decision-making process that includes the patient and physicians as to what, if any, intervention should be performed to best control the disease while minimizing morbidity. Several management principles and variables involved in the decision making for surgery versus active surveillance were developed that should be taken into account when deciding how best to manage a patient with DTC and suspected recurrent or persistent cervical nodal disease.

  5. [Definition of nodal volumes in breast cancer treatment and segmentation guidelines].

    PubMed

    Kirova, Y M; Castro Pena, P; Dendale, R; Campana, F; Bollet, M A; Fournier-Bidoz, N; Fourquet, A

    2009-06-01

    To assist in the determination of breast and nodal volumes in the setting of radiotherapy for breast cancer and establish segmentation guidelines. Materials and methods. Contrast metarial enhanced CT examinations were obtained in the treatment position in 25 patients to clearly define the target volumes. The clinical target volume (CTV) including the breast, internal mammary nodes, supraclavicular and subclavicular regions and axxilary region were segmented along with the brachial plexus and interpectoral nodes. The following critical organs were also segmented: heart, lungs, contralateral breast, thyroid, esophagus and humeral head. A correlation between clinical and imaging findings and meeting between radiation oncologists and breast specialists resulted in a better definition of irradiation volumes for breast and nodes with establishement of segmentation guidelines and creation of an anatomical atlas. A practical approach, based on anatomical criteria, is proposed to assist in the segmentation of breast and node volumes in the setting of breast cancer treatment along with a definition of irradiation volumes.

  6. Electromagnetic modelling of conductive or superconductive microstrip lines using spice as electromagnetic solver

    NASA Astrophysics Data System (ADS)

    Dinh, Thanh Vu; Cabon, Béatrice; Daoud, Nahla; Chilo, Jean

    1992-11-01

    This paper presents a simple and efficient method for calculating the propagating line parameters (actually, a microstrip one) and its magnetic fields, by simulating an original equivalent circuit with an electrical nodal simulator (SPICE). The losses in the normal conducting line (due to DC losses and to skin effect losses) and also in the superconducting one can be investigated. This allows us to integrate the electromagnetic solutions to the CAD softwares. Dans ce papier, une méthode simple et efficace pour calculer les paramètres de propagation d'une ligne microruban et les champs magnétiques qu'elle engendre est présentée; pour cela, nous simulons un circuit original équivalent à l'aide du simulateur nodal SPICE. Les pertes dans une ligne conductrice (pertes continues et par effet de peau) ainsi que dans une ligne supraconductrice peuvent être considérées. Les solutions électromagnétiques peuvent être intégrées dans les simulateurs de CAO.

  7. Dynamic analysis of the tether transportation system using absolute nodal coordinate formulation

    NASA Astrophysics Data System (ADS)

    Sun, Xin; Xu, Ming; Zhong, Rui

    2017-10-01

    Long space tethers are becoming a rising concern as an alternate way for transportation in space. It benefits from fuel economizing. This paper focuses on the dynamics of the tether transportation system, which consists of two end satellites connected by a flexible tether, and a movable vehicle driven by the actuator carried by itself. The Absolute Nodal Coordinate Formulation is applied to the establishment of the equation of motion, so that the influence caused by the distributed mass and elasticity of the tether is introduced. Moreover, an approximated method for accelerating the calculation of the generalized gravitational forces on the tether is proposed by substituting the volume integral every step into summation of finite terms. Afterwards, dynamic evolutions of such a system in different configurations are illustrated using numerical simulations. The deflection of the tether and the trajectory of the crawler during the transportation is investigated. Finally, the effect on the orbit of the system due to the crawler is revealed.

  8. Regional brain network organization distinguishes the combined and inattentive subtypes of Attention Deficit Hyperactivity Disorder.

    PubMed

    Saad, Jacqueline F; Griffiths, Kristi R; Kohn, Michael R; Clarke, Simon; Williams, Leanne M; Korgaonkar, Mayuresh S

    2017-01-01

    Attention Deficit Hyperactivity Disorder (ADHD) is characterized clinically by hyperactive/impulsive and/or inattentive symptoms which determine diagnostic subtypes as Predominantly Hyperactive-Impulsive (ADHD-HI), Predominantly Inattentive (ADHD-I), and Combined (ADHD-C). Neuroanatomically though we do not yet know if these clinical subtypes reflect distinct aberrations in underlying brain organization. We imaged 34 ADHD participants defined using DSM-IV criteria as ADHD-I ( n  = 16) or as ADHD-C ( n  = 18) and 28 matched typically developing controls, aged 8-17 years, using high-resolution T1 MRI. To quantify neuroanatomical organization we used graph theoretical analysis to assess properties of structural covariance between ADHD subtypes and controls (global network measures: path length, clustering coefficient, and regional network measures: nodal degree). As a context for interpreting network organization differences, we also quantified gray matter volume using voxel-based morphometry. Each ADHD subtype was distinguished by a different organizational profile of the degree to which specific regions were anatomically connected with other regions (i.e., in "nodal degree"). For ADHD-I (compared to both ADHD-C and controls) the nodal degree was higher in the hippocampus. ADHD-I also had a higher nodal degree in the supramarginal gyrus, calcarine sulcus, and superior occipital cortex compared to ADHD-C and in the amygdala compared to controls. By contrast, the nodal degree was higher in the cerebellum for ADHD-C compared to ADHD-I and in the anterior cingulate, middle frontal gyrus and putamen compared to controls. ADHD-C also had reduced nodal degree in the rolandic operculum and middle temporal pole compared to controls. These regional profiles were observed in the context of no differences in gray matter volume or global network organization. Our results suggest that the clinical distinction between the Inattentive and Combined subtypes of ADHD may also be reflected in distinct aberrations in underlying brain organization.

  9. Modification of atrioventricular nodal electrophysiology by selective radiofrequency delivery on the anterior or posterior approaches.

    PubMed

    Chorro, F J; Sanchis, J; Such, L; Artal, L; Llavador, J J; Llavador, E; Monmeneu, J V; López-Merino, V

    1997-05-01

    An analysis was made in 14 isolated and perfused rabbit hearts of the electrophysiological effects of selective radiofrequency (RF) delivery in the anterior (group I, n = 7) or posterior zone (group II, n = 7) of the Koch triangle, with the aim of modifying atrioventricular nodal (AVN) conduction without suppressing 1:1 transmission. After opening the right atrium, RF was delivered (0.5 W) with a 1-mm diameter unipolar electrode positioned in the selected zone until a prolongation of no less than 15% was obtained in the Wenckebach cycle length (WCL). Before and after (30 min) RF, anterograde and retrograde AVN refractoriness and conduction were evaluated, stimulating from the crista terminalis (CT), the interatrial septum (IAS), and from the RV epicardium. After RF, the following percentage increments were observed in group I: AH(CT) = 36% +/- 9%, AH(IAS) = 38% +/- 11%, WCL(CT) = 28% +/- 8%, WCL(IAS) = 22% +/- 6%, functional refractory period (FRP) of the AVN(CT) = 13% +/- 11%, FRP-AVN(IAS) = 13% +/- 8%, retrograde WCL = 20% +/- 19%, and retrograde FRPVA = 13% +/- 16%. The increments observed in group II and the significances of the differences with respect to group I were: AH(CT) = 11% +/- 14% (P < 0.01), AH(IAS) = 19% +/- 32% (NS), WCL(CT) = 42% +/- 14% (P < 0.05), WCL(IAS) = 42% +/- 16% (P < 0.01), FRP-AVN(CT) = 28% +/- 28% (NS), FRP-AVN(LAS) = 21% +/- 19% (NS), retrograde WCL = 35% +/- 24% (NS), and retrograde FRP = 16% +/- 13% (NS). In both groups, the AH interval variations were not correlated with those of the rest of the parameters analyzed. Truncated nodal function curves suggestive of a dual AV nodal pathway were obtained in three experiments, though in only one of them was this observed under basal conditions. In the other two experiments, with dual AV nodal physiology only after RF (one from each group), AV nodal reentrant tachycardias were triggered with atrial extrastimulus at coupling intervals equal to or shorter than at those that cause a sudden lengthening of the AH interval, RF delivered in the anterior and posterior zones of the Koch triangle produced effects of different magnitude on the AH interval and Wenckebach cycle length. In the anterior zone the AH interval was prolonged to a greater extent, while in the posterior zone the effects were greater on the Wenckebach cycle length. No correlation existed between the variations in AH interval and Wenckebach cycle length, regardless of where RF was delivered. The evaluation of anterograde AV nodal refractoriness was similar when stimulating from the crista terminalis or from the interatrial septum. By delivering RF, it was possible to induce dual AV nodal physiology and reentrant tachycardias.

  10. VEIL Surgical Steps.

    PubMed

    Raghunath, S K; Nagaraja, H; Srivatsa, N

    2017-03-01

    Inguinal lymphadenectomy remains the standard of care for metastatic nodal disease in cases of penile, urethral, vulval and vaginal cancers. Outcomes, including cure rates and overall and progression-free survivals, have progressively improved in these diseases with extending criteria to offer inguinal lymph node dissection for patients 'at-risk' for metastasis or loco-regional recurrence. Hence, despite declining incidence of advanced stages of these cancers, many patients will still need to undergo lymphadenectomy for optimal oncological outcomes. Inguinal node dissection is a morbid procedure with operative morbidity noted in almost two third of the patients. Video endoscopic inguinal lymphadenectomy (VEIL) was described and currently practiced with proven equivalent oncological outcomes. We describe our technique of VEIL using laparoscopic and robotic access as well as various new surgical strategies.

  11. Transformation of marginal zone lymphoma (and association with other lymphomas).

    PubMed

    Casulo, Carla; Friedberg, Jonathan

    Marginal zone lymphomas (MZL) are a diverse group of indolent lymphoproliferative disorders that comprise three subtypes: nodal, splenic and mucosal associated marginal zone lymphomas (MALT). Histologic transformation (HT) to an aggressive lymphoma is a rare event that can occur in any subtype, and at lower frequency compared to other indolent non Hodgkin lymphomas (NHL) like follicular lymphoma. There are few data directly associated with risk and prognosis of transformation in MZL. However, recent advances in the understanding of molecular and genetic features of MALT have contributed to an evolving appreciation of HT in this disease. Optimal treatment of HT of MZL remains unknown. Much of the approach to managing transformed MZL is extrapolated from other indolent NHLs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. The effects of oral glutamine on clinical and survival outcomes of non-small cell lung cancer patients treated with chemoradiotherapy.

    PubMed

    Gul, Kanyilmaz; Mehmet, Koc; Meryem, Aktan

    2017-08-01

    To assess the efficacy of oral glutamine (Gln) supplementation on clinical and survival outcomes of patients with locally advanced non-small cell lung cancer (LA-NSCLC). Between 2010 and 2014, 122 stage III NSCLC patients were retrospectively analyzed. All patients received curative intent chemoradiotherapy (CRT). Prophylactic oral Gln powder was applied at a dose of 10 g tid. Effect of oral Gln supplementation in the prevention of severe (≥grade 2-3) acute radiation-induced esophagitis (ARE) and weight loss, and their relation with overall survival (OS) and disease-free survival (DFS) was measured. Median follow-up was 13.14 months (range; 1.97-55.36). Fifty-six (46%) patients had received oral Gln. Severe ARE was significantly lower in Gln-supplemented group (30% vs 70%; p = 0.002). Gln-free patients demonstrated a higher weight loss (p = 0.0001). In multivariate analysis hemoglobin (hb) level (<12 g/dL; p = 0.01) and nodal stage (N3; p = 0.01) were poor prognostic factors that affect OS; Weight loss (p = 0.06) and Gln-free (p = 0.05) reached nearly significant levels that poorly affect OS. Similarly, nodal stage (N3, p = 0.014) and Gln-free (p = 0.035) were poor prognostic factors that affect DFS. Weight loss (≥2%, p = 0.06) and hb level (<12 g/dL, p = 0.07) reached borderline significance that poorly affect DFS. Nodal stage (N3) was the only poor prognostic factor that affect OS and DFS in univariate analysis (p = 0.01, p = 0.009; respectively). Oral Gln supplementation significantly reduces grade 2-3 esophagitis and weight loss and also no negative impact on tumor control and survival outcomes in patients with LA-NSCLC. Copyright © 2016 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

  13. A penalty-based nodal discontinuous Galerkin method for spontaneous rupture dynamics

    NASA Astrophysics Data System (ADS)

    Ye, R.; De Hoop, M. V.; Kumar, K.

    2017-12-01

    Numerical simulation of the dynamic rupture processes with slip is critical to understand the earthquake source process and the generation of ground motions. However, it can be challenging due to the nonlinear friction laws interacting with seismicity, coupled with the discontinuous boundary conditions across the rupture plane. In practice, the inhomogeneities in topography, fault geometry, elastic parameters and permiability add extra complexity. We develop a nodal discontinuous Galerkin method to simulate seismic wave phenomenon with slipping boundary conditions, including the fluid-solid boundaries and ruptures. By introducing a novel penalty flux, we avoid solving Riemann problems on interfaces, which makes our method capable for general anisotropic and poro-elastic materials. Based on unstructured tetrahedral meshes in 3D, the code can capture various geometries in geological model, and use polynomial expansion to achieve high-order accuracy. We consider the rate and state friction law, in the spontaneous rupture dynamics, as part of a nonlinear transmitting boundary condition, which is weakly enforced across the fault surface as numerical flux. An iterative coupling scheme is developed based on implicit time stepping, containing a constrained optimization process that accounts for the nonlinear part. To validate the method, we proof the convergence of the coupled system with error estimates. We test our algorithm on a well-established numerical example (TPV102) of the SCEC/USGS Spontaneous Rupture Code Verification Project, and benchmark with the simulation of PyLith and SPECFEM3D with agreeable results.

  14. Acquiring Domain Knowledge for Planning by Experimentation

    DTIC Science & Technology

    1992-01-01

    visel partt holding grinderi visel p=r1 size-of pull LENGTH k size-of part! LENGTH k ufsee-finish pertl side! ROUGH surface-tinish pan] side...prof-not-cached <nodal> <node2>) (current-goal <nodal> ( goali )) (current-goal (node2> <goal2>) (d@.s-top-protection-violat ion <goal2>) (not-does-top

  15. Benign vascular proliferation in a lymph node following acute toxoplasmosis. A differential diagnosis from Kaposi's sarcoma.

    PubMed

    Rousselet, M C; Saint-André, J P; Beaufils, J M; Diebold, J

    1988-12-01

    We describe an unusual intranodal vascular proliferation following acute toxoplasmosis in a man. This proliferation is distinct from other benign vasoformative nodal lesions. It could be interpreted as a reactive healing process that might be misdiagnosed as nodal Kaposi's sarcoma. Some criteria to avoid such misdiagnosis are presented.

  16. Anomalous contagion and renormalization in networks with nodal mobility

    NASA Astrophysics Data System (ADS)

    Manrique, Pedro D.; Qi, Hong; Zheng, Minzhang; Xu, Chen; Hui, Pak Ming; Johnson, Neil F.

    2016-07-01

    A common occurrence in everyday human activity is where people join, leave and possibly rejoin clusters of other individuals —whether this be online (e.g. social media communities) or in real space (e.g. popular meeting places such as cafes). In the steady state, the resulting interaction network would appear static over time if the identities of the nodes are ignored. Here we show that even in this static steady-state limit, a non-zero nodal mobility leads to a diverse set of outbreak profiles that is dramatically different from known forms, and yet matches well with recent real-world social outbreaks. We show how this complication of nodal mobility can be renormalized away for a particular class of networks.

  17. Outcomes in a multi-institutional cohort of patients treated with intraoperative radiation therapy for advanced or recurrent renal cell carcinoma.

    PubMed

    Paly, Jonathan J; Hallemeier, Christopher L; Biggs, Peter J; Niemierko, Andrzej; Roeder, Falk; Martínez-Monge, Rafael; Whitson, Jared; Calvo, Felipe A; Fastner, Gerd; Sedlmayer, Felix; Wong, William W; Ellis, Rodney J; Haddock, Michael G; Choo, Richard; Shipley, William U; Zietman, Anthony L; Efstathiou, Jason A

    2014-03-01

    This study aimed to analyze outcomes in a multi-institutional cohort of patients with advanced or recurrent renal cell carcinoma (RCC) who were treated with intraoperative radiation therapy (IORT). Between 1985 and 2010, 98 patients received IORT for advanced or locally recurrent RCC at 9 institutions. The median follow-up time for surviving patients was 3.5 years. Overall survival (OS), disease-specific survival (DSS), and disease-free survival (DFS) were estimated with the Kaplan-Meier method. Chained imputation accounted for missing data, and multivariate Cox hazards regression tested significance. IORT was delivered during nephrectomy for advanced disease (28%) or during resection of locally recurrent RCC in the renal fossa (72%). Sixty-nine percent of the patients were male, and the median age was 58 years. At the time of primary resection, the T stages were as follows: 17% T1, 12% T2, 55% T3, and 16% T4. Eighty-seven percent of the patients had a visibly complete resection of tumor. Preoperative or postoperative external beam radiation therapy was administered to 27% and 35% of patients, respectively. The 5-year OS was 37% for advanced disease and 55% for locally recurrent disease. The respective 5-year DSS was 41% and 60%. The respective 5-year DFS was 39% and 52%. Initial nodal involvement (hazard ratio [HR] 2.9-3.6, P<.01), presence of sarcomatoid features (HR 3.7-6.9, P<.05), and higher IORT dose (HR 1.3, P<.001) were statistically significantly associated with decreased survival. Adjuvant systemic therapy was associated with decreased DSS (HR 2.4, P=.03). For locally recurrent tumors, positive margin status (HR 2.6, P=.01) was associated with decreased OS. We report the largest known cohort of patients with RCC managed by IORT and have identified several factors associated with survival. The outcomes for patients receiving IORT in the setting of local recurrence compare favorably to similar cohorts treated by local resection alone suggesting the potential for improved DFS with IORT. Copyright © 2014 Elsevier Inc. All rights reserved.

  18. An efficient multi-objective optimization method for water quality sensor placement within water distribution systems considering contamination probability variations.

    PubMed

    He, Guilin; Zhang, Tuqiao; Zheng, Feifei; Zhang, Qingzhou

    2018-06-20

    Water quality security within water distribution systems (WDSs) has been an important issue due to their inherent vulnerability associated with contamination intrusion. This motivates intensive studies to identify optimal water quality sensor placement (WQSP) strategies, aimed to timely/effectively detect (un)intentional intrusion events. However, these available WQSP optimization methods have consistently presumed that each WDS node has an equal contamination probability. While being simple in implementation, this assumption may do not conform to the fact that the nodal contamination probability may be significantly regionally varied owing to variations in population density and user properties. Furthermore, the low computational efficiency is another important factor that has seriously hampered the practical applications of the currently available WQSP optimization approaches. To address these two issues, this paper proposes an efficient multi-objective WQSP optimization method to explicitly account for contamination probability variations. Four different contamination probability functions (CPFs) are proposed to represent the potential variations of nodal contamination probabilities within the WDS. Two real-world WDSs are used to demonstrate the utility of the proposed method. Results show that WQSP strategies can be significantly affected by the choice of the CPF. For example, when the proposed method is applied to the large case study with the CPF accounting for user properties, the event detection probabilities of the resultant solutions are approximately 65%, while these values are around 25% for the traditional approach, and such design solutions are achieved approximately 10,000 times faster than the traditional method. This paper provides an alternative method to identify optimal WQSP solutions for the WDS, and also builds knowledge regarding the impacts of different CPFs on sensor deployments. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. Proposed Lymph Node Staging System Using the International Consensus Guidelines for Lymph Node Levels Is Predictive for Nasopharyngeal Carcinoma Patients From Endemic Areas Treated With Intensity Modulated Radiation Therapy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Li, Wen-Fei; Sun, Ying; Mao, Yan-Ping

    2013-06-01

    Purpose: To propose a lymph node (N) staging system for nasopharyngeal carcinoma (NPC) based on the International Consensus Guidelines for lymph node (LN) levels and MRI-determined nodal variables. Methods and Materials: The MRI scans and medical records of 749 NPC patients receiving intensity modulated radiation therapy with or without chemotherapy were retrospectively reviewed. The prognostic significance of nodal level, laterality, maximal axial diameter, extracapsular spread, necrosis, and Union for International Cancer Control/American Joint Committee on Cancer (UICC/AJCC) size criteria were analyzed. Results: Nodal level and laterality were the only independent prognostic factors for distant failure and disease failure in multivariatemore » analysis. Compared with unilateral levels Ib, II, III, and/or Va involvement (hazard ratio [HR] 1), retropharyngeal lymph node involvement alone had a similar prognostic value (HR 0.71; 95% confidence interval [CI] 0.43-1.17; P=.17), whereas bilateral levels Ib, II, III, and/or Va involvement (HR 1.65; 95% CI 1.06-2.58; P=.03) and levels IV, Vb, and/or supraclavicular fossa involvement (HR 3.47; 95% CI 1.92-6.29; P<.01) both significantly increased the HR for distant failure. Thus we propose that the N category criteria could be revised as follows: N0, no regional LN metastasis; N1, retropharyngeal lymph node involvement, and/or unilateral levels Ib, II, III, and/or Va involvement; N2, bilateral levels Ib, II, III, and/or Va involvement; N3, levels IV, Vb, and/or supraclavicular fossa involvement. Compared with the 7th edition of the UICC/AJCC criteria, the proposed N staging system provides a more satisfactory distinction between the HRs for regional failure, distant failure, and disease failure in each N category. Conclusions: The proposed N staging system defined by the International Consensus Guidelines and laterality is predictive and practical. However, because of no measurements of the maximal nodal diameter on MRI slices, the prognostic significance of LN size needs further evaluation.« less

  20. Breast Cancer Laterality Does Not Influence Survival in a Large Modern Cohort: Implications for Radiation-Related Cardiac Mortality

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Rutter, Charles E., E-mail: charles.rutter@yale.edu; Chagpar, Anees B.; Cancer Outcomes, Public Policy and Effectiveness Research Center, Yale School of Medicine, New Haven, Connecticut

    2014-10-01

    Objectives: Radiation therapy for left-sided breast cancer has been associated with an elevated risk of cardiac mortality, based on studies predating treatment planning based on computed tomography. This study assessed the impact of tumor laterality on overall survival (OS) in a large cohort treated with modern techniques, to indirectly determine whether left-sided treatment remains associated with increased cardiac mortality. Methods and Materials: Patients treated for breast cancer with breast conserving surgery and adjuvant external beam radiation therapy were identified in the National Cancer Database, and OS was compared based on tumor laterality using Kaplan-Meier analysis. Separate analyses were performed formore » noninvasive and invasive carcinoma and for breast-only and breast plus regional nodal radiation therapy. Multivariate regression analysis of OS was performed with demographic, pathologic, and treatment variables as covariates to adjust for factors associated with breast cancer–specific survival. Results: We identified 344,831 patients whose cancer was diagnosed from 1998 to 2006 with a median follow-up time of 6.04 years (range, 0-14.17 years). Clinical, tumor, and treatment characteristics were similar between laterality groups. Regional nodal radiation was used in 14.2% of invasive cancers. No OS difference was noted based on tumor laterality for patients treated with breast-only (hazard ratio [HR] 0.984, P=.132) and breast plus regional nodal radiation therapy (HR 1.001, P=.957). In multivariate analysis including potential confounders, OS was identical between left and right sided cancers (HR 1.002, P=.874). No significant OS difference by laterality was observed when analyses were restricted to patients with at least 10 years of follow-up (n=27,725), both in patients treated with breast-only (HR 0.955, P=.368) and breast plus regional nodal radiation therapy (HR 0.859, P=.155). Conclusions: Radiation therapy for left-sided breast cancer does not appear to increase the risk of death in this national database relative to right-sided tumors. Consequently, radiation therapy–induced cardiac disease may be less prominent than previously demonstrated.« less

  1. Prognostic Significance of Tumor Size of Small Lung Adenocarcinomas Evaluated with Mediastinal Window Settings on Computed Tomography

    PubMed Central

    Sakao, Yukinori; Kuroda, Hiroaki; Mun, Mingyon; Uehara, Hirofumi; Motoi, Noriko; Ishikawa, Yuichi; Nakagawa, Ken; Okumura, Sakae

    2014-01-01

    Background We aimed to clarify that the size of the lung adenocarcinoma evaluated using mediastinal window on computed tomography is an important and useful modality for predicting invasiveness, lymph node metastasis and prognosis in small adenocarcinoma. Methods We evaluated 176 patients with small lung adenocarcinomas (diameter, 1–3 cm) who underwent standard surgical resection. Tumours were examined using computed tomography with thin section conditions (1.25 mm thick on high-resolution computed tomography) with tumour dimensions evaluated under two settings: lung window and mediastinal window. We also determined the patient age, gender, preoperative nodal status, tumour size, tumour disappearance ratio, preoperative serum carcinoembryonic antigen levels and pathological status (lymphatic vessel, vascular vessel or pleural invasion). Recurrence-free survival was used for prognosis. Results Lung window, mediastinal window, tumour disappearance ratio and preoperative nodal status were significant predictive factors for recurrence-free survival in univariate analyses. Areas under the receiver operator curves for recurrence were 0.76, 0.73 and 0.65 for mediastinal window, tumour disappearance ratio and lung window, respectively. Lung window, mediastinal window, tumour disappearance ratio, preoperative serum carcinoembryonic antigen levels and preoperative nodal status were significant predictive factors for lymph node metastasis in univariate analyses; areas under the receiver operator curves were 0.61, 0.76, 0.72 and 0.66, for lung window, mediastinal window, tumour disappearance ratio and preoperative serum carcinoembryonic antigen levels, respectively. Lung window, mediastinal window, tumour disappearance ratio, preoperative serum carcinoembryonic antigen levels and preoperative nodal status were significant factors for lymphatic vessel, vascular vessel or pleural invasion in univariate analyses; areas under the receiver operator curves were 0.60, 0.81, 0.81 and 0.65 for lung window, mediastinal window, tumour disappearance ratio and preoperative serum carcinoembryonic antigen levels, respectively. Conclusions According to the univariate analyses including a logistic regression and ROCs performed for variables with p-values of <0.05 on univariate analyses, our results suggest that measuring tumour size using mediastinal window on high-resolution computed tomography is a simple and useful preoperative prognosis modality in small adenocarcinoma. PMID:25365326

  2. Beat-to-Beat Variation in Periodicity of Local Calcium Releases Contributes to Intrinsic Variations of Spontaneous Cycle Length in Isolated Single Sinoatrial Node Cells

    PubMed Central

    Monfredi, Oliver; Maltseva, Larissa A.; Spurgeon, Harold A.; Boyett, Mark R.; Lakatta, Edward G.; Maltsev, Victor A.

    2013-01-01

    Spontaneous, submembrane local Ca2+ releases (LCRs) generated by the sarcoplasmic reticulum in sinoatrial nodal cells, the cells of the primary cardiac pacemaker, activate inward Na+/Ca2+-exchange current to accelerate the diastolic depolarization rate, and therefore to impact on cycle length. Since LCRs are generated by Ca2+ release channel (i.e. ryanodine receptor) openings, they exhibit a degree of stochastic behavior, manifested as notable cycle-to-cycle variations in the time of their occurrence. Aim The present study tested whether variation in LCR periodicity contributes to intrinsic (beat-to-beat) cycle length variability in single sinoatrial nodal cells. Methods We imaged single rabbit sinoatrial nodal cells using a 2D-camera to capture LCRs over the entire cell, and, in selected cells, simultaneously measured action potentials by perforated patch clamp. Results LCRs begin to occur on the descending part of the action potential-induced whole-cell Ca2+ transient, at about the time of the maximum diastolic potential. Shortly after the maximum diastolic potential (mean 54±7.7 ms, n = 14), the ensemble of waxing LCR activity converts the decay of the global Ca2+ transient into a rise, resulting in a late, whole-cell diastolic Ca2+ elevation, accompanied by a notable acceleration in diastolic depolarization rate. On average, cells (n = 9) generate 13.2±3.7 LCRs per cycle (mean±SEM), varying in size (7.1±4.2 µm) and duration (44.2±27.1 ms), with both size and duration being greater for later-occurring LCRs. While the timing of each LCR occurrence also varies, the LCR period (i.e. the time from the preceding Ca2+ transient peak to an LCR’s subsequent occurrence) averaged for all LCRs in a given cycle closely predicts the time of occurrence of the next action potential, i.e. the cycle length. Conclusion Intrinsic cycle length variability in single sinoatrial nodal cells is linked to beat-to-beat variations in the average period of individual LCRs each cycle. PMID:23826247

  3. Macroscopy predicts tumor progression in gastric cancer: A retrospective patho-historical analysis based on Napoleon Bonaparte's autopsy report.

    PubMed

    Dawson, Heather; Novotny, Alexander; Becker, Karen; Reim, Daniel; Langer, Rupert; Gullo, Irene; Svrcek, Magali; Niess, Jan H; Tutuian, Radu; Truninger, Kaspar; Diamantis, Ioannis; Blank, Annika; Zlobec, Inti; Riddell, Robert H; Carneiro, Fatima; Fléjou, Jean-François; Genta, Robert M; Lugli, Alessandro

    2016-11-01

    The cause of Napoleon Bonaparte's death remains controversial. Originally suggested to be gastric cancer, whether this was truly neoplastic or a benign lesion has been recently debated. To interpret findings of original autopsy reports in light of the current knowledge of gastric cancer and to highlight the significance of accurate macroscopy in modern-day medicine. Using original autopsy documents, endoscopic images and data from current literature, Napoleon's gastric situation was reconstructed. In a multicenter collection of 2071 gastric cancer specimens, the relationship between tumor size and features of tumor progression was assessed. Greater tumor size was associated with advanced pT, nodal metastases and Borrmann types 3-4 (p<0.001). The best cut-off for predicting pT3-4 tumors was 6.5cm (AUC 0.8; OR 1.397, 95% CI 1.35-1.446), and 6cm for lymph node metastases (AUC 0.775; OR 1.389, 95% CI 1.338-1.442). The 6cm cut-off of had a positive predictive value of 0.820 for nodal metastases and a negative predictive value of 0.880 for distant metastases. This analysis combines Napoleon's autopsy with present-day knowledge to support gastric cancer as his terminal illness and emphasizes the role of macroscopy, which may provide valuable information on gastric cancer progression and aid patient management. Copyright © 2016 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.

  4. Canine nodal marginal zone lymphoma: Descriptive insight into the biological behaviour.

    PubMed

    Cozzi, M; Marconato, L; Martini, V; Aresu, L; Riondato, F; Rossi, F; Stefanello, D; Comazzi, S

    2018-06-01

    Canine nodal marginal zone lymphoma (nMZL) is classified as an indolent lymphoma. Such lymphomas are typified by low mitotic rate and slow clinical progression. While the clinical behaviour of canine splenic MZL has been described, characterized by an indolent course and a good prognosis following splenectomy, there are no studies specifically describing nMZL. The aim of this study was to describe the clinical features of and outcome for canine nMZL. Dogs with histologically confirmed nMZL undergoing a complete staging work-up (including blood analysis, flow cytometry [FC] on lymph node [LN], peripheral blood and bone marrow, imaging, histology and immunohistochemistry on a surgically removed peripheral LN) were retrospectively enrolled. Treatment consisted of chemotherapy or chemo-immunotherapy. Endpoints were response rate (RR), time to progression (TTP) and lymphoma-specific survival (LSS). A total of 35 cases were enrolled. At diagnosis, all dogs showed generalized lymphadenopathy. One-third was systemically unwell. All dogs had stage V disease; one-third also had extranodal involvement. The LN population was mainly composed of medium-sized CD21+ cells with scant resident normal lymphocytes. Histology revealed diffuse LN involvement, referring to "late-stage" MZL. Median TTP and LSS were 149 and 259 days, respectively. Increased LDH activity and substage b were significantly associated with a shorter LSS. Dogs with nMZL may show generalized lymphadenopathy and an advanced disease stage. Overall, the outcome is poor, despite the "indolent" designation. The best treatment option still needs to be defined. © 2017 John Wiley & Sons Ltd.

  5. Recent Progress in Discrete Dislocation Dynamics and Its Applications to Micro Plasticity

    NASA Astrophysics Data System (ADS)

    Po, Giacomo; Mohamed, Mamdouh S.; Crosby, Tamer; Erel, Can; El-Azab, Anter; Ghoniem, Nasr

    2014-10-01

    We present a self-contained review of the discrete dislocation dynamics (DDD) method for the numerical investigation of plasticity in crystals, focusing on recent development and implementation progress. The review covers the theoretical foundations of DDD within the framework of incompatible elasticity, its numerical implementation via the nodal method, the extension of the method to finite domains and several implementation details. Applications of the method to current topics in micro-plasticity are presented, including the size effects in nano-indentation, the evolution of the dislocation microstructure in persistent slip bands, and the phenomenon of dislocation avalanches in micro-pillar compression.

  6. Local opiate receptors in the sinoatrial node moderate vagal bradycardia.

    PubMed

    Farias, M; Jackson, K; Stanfill, A; Caffrey, J L

    2001-02-20

    Met-enkephalin-arg-phe (MEAP) interrupts vagal bradycardia when infused into the systemic circulation. This study was designed to locate the opiate receptors functionally responsible for this inhibition. Previous observations suggested that the receptors were most likely located in either intracardiac parasympathetic ganglia or the pre-junctional nerve terminals innervating the sinoatrial node. In this study 10 dogs were instrumented with a microdialysis probe inserted into the sinoatrial node. The functional position of the probe was tested by briefly introducing norepinephrine into the probe producing an increase in heart rate of more than 30 beats/min. Vagal stimulations were conducted at 0.5, 1.2 and 4 Hz during vehicle infusion (saline ascorbate). Cardiovascular responses during vagal stimulation were recorded on-line. MEAP was infused directly into the sinoatrial node via the microdialysis probe. The evaluation of vagal bradycardia was repeated during the nodal application of MEAP, diprenorphine (opiate antagonist), and diprenorphine co-infused with MEAP. MEAP introduced into the sinoatrial node via the microdialysis probe reduced vagal bradycardia by more than half. Simultaneous local nodal blockade of these receptors with the opiate antagonist, diprenorphine, eliminated the effect of MEAP demonstrating the participation by opiate receptors. Systemic infusions of MEAP produced a reduction in vagal bradycardia nearly identical to that observed during nodal administration. When local nodal opiate receptors were blocked with diprenorphine, the systemic effect of MEAP was eliminated. These data lead us to suggest that the opiate receptors responsible for the inhibition of vagal bradycardia are located within the sinoatrial node with few, if any, participating extra-nodal or ganglionic receptors.

  7. Disrupted Nodal and Hub Organization Account for Brain Network Abnormalities in Parkinson’s Disease

    PubMed Central

    Koshimori, Yuko; Cho, Sang-Soo; Criaud, Marion; Christopher, Leigh; Jacobs, Mark; Ghadery, Christine; Coakeley, Sarah; Harris, Madeleine; Mizrahi, Romina; Hamani, Clement; Lang, Anthony E.; Houle, Sylvain; Strafella, Antonio P.

    2016-01-01

    The recent application of graph theory to brain networks promises to shed light on complex diseases such as Parkinson’s disease (PD). This study aimed to investigate functional changes in sensorimotor and cognitive networks in Parkinsonian patients, with a focus on inter- and intra-connectivity organization in the disease-associated nodal and hub regions using the graph theoretical analyses. Resting-state functional MRI data of a total of 65 participants, including 23 healthy controls (HCs) and 42 patients, were investigated in 120 nodes for local efficiency, betweenness centrality, and degree. Hub regions were identified in the HC and patient groups. We found nodal and hub changes in patients compared with HCs, including the right pre-supplementary motor area (SMA), left anterior insula, bilateral mid-insula, bilateral dorsolateral prefrontal cortex (DLPFC), and right caudate nucleus. In general, nodal regions within the sensorimotor network (i.e., right pre-SMA and right mid-insula) displayed weakened connectivity, with the former node associated with more severe bradykinesia, and impaired integration with default mode network regions. The left mid-insula also lost its hub properties in patients. Within the executive networks, the left anterior insular cortex lost its hub properties in patients, while a new hub region was identified in the right caudate nucleus, paralleled by an increased level of inter- and intra-connectivity in the bilateral DLPFC possibly representing compensatory mechanisms. These findings highlight the diffuse changes in nodal organization and regional hub disruption accounting for the distributed abnormalities across brain networks and the clinical manifestations of PD. PMID:27891090

  8. Disrupted Nodal and Hub Organization Account for Brain Network Abnormalities in Parkinson's Disease.

    PubMed

    Koshimori, Yuko; Cho, Sang-Soo; Criaud, Marion; Christopher, Leigh; Jacobs, Mark; Ghadery, Christine; Coakeley, Sarah; Harris, Madeleine; Mizrahi, Romina; Hamani, Clement; Lang, Anthony E; Houle, Sylvain; Strafella, Antonio P

    2016-01-01

    The recent application of graph theory to brain networks promises to shed light on complex diseases such as Parkinson's disease (PD). This study aimed to investigate functional changes in sensorimotor and cognitive networks in Parkinsonian patients, with a focus on inter- and intra-connectivity organization in the disease-associated nodal and hub regions using the graph theoretical analyses. Resting-state functional MRI data of a total of 65 participants, including 23 healthy controls (HCs) and 42 patients, were investigated in 120 nodes for local efficiency, betweenness centrality, and degree. Hub regions were identified in the HC and patient groups. We found nodal and hub changes in patients compared with HCs, including the right pre-supplementary motor area (SMA), left anterior insula, bilateral mid-insula, bilateral dorsolateral prefrontal cortex (DLPFC), and right caudate nucleus. In general, nodal regions within the sensorimotor network (i.e., right pre-SMA and right mid-insula) displayed weakened connectivity, with the former node associated with more severe bradykinesia, and impaired integration with default mode network regions. The left mid-insula also lost its hub properties in patients. Within the executive networks, the left anterior insular cortex lost its hub properties in patients, while a new hub region was identified in the right caudate nucleus, paralleled by an increased level of inter- and intra-connectivity in the bilateral DLPFC possibly representing compensatory mechanisms. These findings highlight the diffuse changes in nodal organization and regional hub disruption accounting for the distributed abnormalities across brain networks and the clinical manifestations of PD.

  9. Translational co-regulation of a ligand and inhibitor by a conserved RNA element

    PubMed Central

    Zaucker, Andreas; Nagorska, Agnieszka; Kumari, Pooja; Hecker, Nikolai; Wang, Yin; Huang, Sizhou; Cooper, Ledean; Sivashanmugam, Lavanya; VijayKumar, Shruthi; Brosens, Jan; Gorodkin, Jan

    2018-01-01

    Abstract In many organisms, transcriptional and post-transcriptional regulation of components of pathways or processes has been reported. However, to date, there are few reports of translational co-regulation of multiple components of a developmental signaling pathway. Here, we show that an RNA element which we previously identified as a dorsal localization element (DLE) in the 3′UTR of zebrafish nodal-related1/squint (ndr1/sqt) ligand mRNA, is shared by the related ligand nodal-related2/cyclops (ndr2/cyc) and the nodal inhibitors, lefty1 (lft1) and lefty2 mRNAs. We investigated the activity of the DLEs through functional assays in live zebrafish embryos. The lft1 DLE localizes fluorescently labeled RNA similarly to the ndr1/sqt DLE. Similar to the ndr1/sqt 3′UTR, the lft1 and lft2 3′UTRs are bound by the RNA-binding protein (RBP) and translational repressor, Y-box binding protein 1 (Ybx1), whereas deletions in the DLE abolish binding to Ybx1. Analysis of zebrafish ybx1 mutants shows that Ybx1 represses lefty1 translation in embryos. CRISPR/Cas9-mediated inactivation of human YBX1 also results in human NODAL translational de-repression, suggesting broader conservation of the DLE RNA element/Ybx1 RBP module in regulation of Nodal signaling. Our findings demonstrate translational co-regulation of components of a signaling pathway by an RNA element conserved in both sequence and structure and an RBP, revealing a ‘translational regulon’. PMID:29059375

  10. NODAL in the Uterus Is Necessary for Proper Placental Development and Maintenance of Pregnancy1

    PubMed Central

    Park, Craig B.; DeMayo, Francesco J.; Lydon, John P.; Dufort, Daniel

    2012-01-01

    Preterm birth is the single leading cause of perinatal mortality in developed countries, affecting approximately 12% of pregnancies and accounting for 75% of neonatal loss in the United States. Despite the prevalence and severity of premature delivery, the causes and mechanisms that underlie spontaneous and idiopathic preterm birth remain unknown. Our inability to elucidate these fundamental causes has been attributed to a poor understanding of the signaling pathways associated with the premature induction of parturition and a lack of suitable animal models available for preterm birth research. In this study, we describe the generation and analysis of a novel conditional knockout of the transforming growth factor beta (TGFB) superfamily member, Nodal, from the maternal reproductive tract of mice. Strikingly, uterine Nodal knockout females exhibited a severe malformation of the maternal decidua basalis during placentation, leading to significant intrauterine growth restriction, and ultimately preterm birth and fetal loss on Day 17.5 of gestation. Using several approaches, we characterized aberrant placental development and demonstrated that reduced proliferation combined with increased apoptosis resulted in a diminished decidua basalis and compromised maternal-fetal interface. Last, we evaluated various components of the established parturition cascade and determined that preterm birth derived from the maternal Nodal knockout occurs prior to PTGS2 (COX-2) upregulation at the placental interface. Taken together, the results presented in this study highlight an in vivo role for maternal NODAL during placentation, present an interesting link between disrupted decidua basalis formation and premature parturition, and describe a potentially valuable model toward elucidating the complex processes that underlie preterm birth. PMID:22378764

  11. Effectiveness of Implemented Interventions on Pathologic Nodal Staging of Non-Small Cell Lung Cancer.

    PubMed

    Ray, Meredith A; Faris, Nicholas R; Smeltzer, Matthew P; Fehnel, Carrie; Houston-Harris, Cheryl; Levy, Paul; Wiggins, Lynn; Sachdev, Vishal; Robbins, Todd; Spencer, David; Osarogiagbon, Raymond U

    2018-03-10

    Accurate pathologic nodal staging improves early-stage non-small-cell lung cancer survival. In an ongoing implementation study, we measured the impact of a surgical lymph node specimen collection kit and a more thorough pathologic gross dissection method, on attainment of guideline-recommended pathologic nodal staging quality. We prospectively collected data on curative-intent non-small cell lung cancer resections from 2009-2016 from 11 hospitals in 4 contiguous Dartmouth Hospital Referral Regions. We categorized patients into 4 groups based on exposure to the two interventions in our staggered implementation study design. We used Chi-squared tests to examine the differences in demographic and disease characteristics and surgical quality criteria across implementation groups. Of 2,469 patients, 1,615 (65%) received neither intervention; 167 (7%) received only the pathology intervention; 264 (11%) received only the surgery intervention; 423 (17%) had both. Rates of non-examination of lymph nodes reduced sequentially in the order of no intervention, novel dissection, kit, and combined interventions, including non-examination of: any lymph nodes, hilar/intrapulmonary and mediastinal nodes (p<0.001 for all comparisons). The rates of attainment of National Comprehensive Cancer Network, Commission on Cancer, American Joint Committee on Cancer, and American College of Surgeons Oncology Group guidelines increased significantly in the same sequential order (p<0.001 for all comparisons). The combined effect of two interventions to improve pathologic lymph node examination has a greater effect on attainment of a range of surgical quality criteria than either intervention alone. Copyright © 2018 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

  12. Merkel Cell Carcinoma of Unknown Primary Origin

    PubMed Central

    Deneve, Jeremiah L.; Messina, Jane L.; Marzban, Suroosh S.; Gonzalez, Ricardo J.; Walls, Brooke M.; Fisher, Kate J.; Ann Chen, Y.; Wayne Cruse, C.; Sondak, Vernon K.; Zager, Jonathan S.

    2015-01-01

    Background Merkel cell carcinoma (MCC) is a rare neuroendocrine tumor of the skin. MCC from an unknown primary origin (MCCUP) can present a diagnostic and therapeutic challenge. We describe our single-institution experience with the diagnosis and management of MCCUP presenting as metastases to lymph nodes. Methods After institutional review board approval, our institutional database spanning the years 1998–2010 was queried for patients with MCCUP. Clinicopathologic variables and outcomes were assessed. Results From a database of 321 patients with MCC, 38 (12%) were identified as having nodal MCCUP. Median age was 67 years, and 79% were men. Nodal basins involved at presentation were cervical (58%), axillary/epitrochlear (21%), or inguinal/iliac (21%). CK20 staining was positive in 93% of tumors tested, and all were negative for thyroid transcription factor-1. Twenty-nine patients (76%) underwent complete regional lymph node dissection (LND): 3 had LND alone, ten had LND and adjuvant radiotherapy, and 16 underwent LND followed by chemoradiotherapy. Definitive chemoradiotherapy without surgery was provided to six patients (16%), while radiotherapy alone was provided to three (8%). Recurrence was observed in 34% of patients. Median recurrence-free survival was 35 months. Ten patients (26%) died, five of disease and five of other causes. The median overall survival was 104 months. Conclusions Nodal MCCUP is a rare disease affecting primarily elderly white men. Recurrence is observed in approximately one-third of patients, with a 104 month median overall survival after a multimodal treatment approach consisting of surgery along with adjuvant chemotherapy and radiotherapy in the majority of patients. PMID:22271206

  13. Rationality of moduli space of torsion-free sheaves over reducible curve

    NASA Astrophysics Data System (ADS)

    Dey, Arijit; Suhas, B. N.

    2018-06-01

    Let M(2 , w ̲ , χ) be the moduli space of rank 2 torsion-free sheaves of fixed determinant and odd Euler characteristic over a reducible nodal curve with each irreducible component having utmost two nodal singularities. We show that in each irreducible component of M(2 , w ̲ , χ) , the closure of rank 2 vector bundles is rational.

  14. Brady's Geothermal Field Nodal Seismometer Earthquake Data

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kurt Feigl

    90-second records of data from 238 three-component nodal seismometer deployed at Bradys geothermal field. The time window catches an earthquake arrival. Earthquake data from USGS online catalog: Magnitude: 4.3 ml +/- 0.4 Location: 38.479 deg N 118.366 deg W +/- 0.7 km Depth: 9.9 km +/- 0.7 Date and Time: 2016-03-21 07:37:10.535 UTC

  15. Identification and expression of Smads associated with TGF-beta/activin/nodal signaling pathways in the rainbow trout (Oncorhynuchus mykiss)

    USDA-ARS?s Scientific Manuscript database

    The Smad proteins are essential components of the TGF-beta/activin/nodal family signaling pathway. We report the identification and characterization of transcripts representing 3 receptor Smads (Smad2a, Smad2b, Smad3), 2 common Smads (Smad4a, Smad4b) and one inhibitory Smad (Smad7). Phylogenetic an...

  16. Zebrafish hhex, nk2.1a, and pax2.1 regulate thyroid growth and differentiation downstream of Nodal-dependent transcription factors.

    PubMed

    Elsalini, Osama A; von Gartzen, Julia; Cramer, Matthias; Rohr, Klaus B

    2003-11-01

    During zebrafish development, the thyroid primordium initiates expression of molecular markers such as hhex and nk2.1a in the endoderm prior to pharynx formation. As expected for an endodermally derived organ, initiation of thyroid development depends on Nodal signalling. We find that it also depends on three downstream effectors of Nodal activity, casanova (cas), bonnie and clyde (bon), and faust (fau)/gata5. Despite their early Nodal-dependent expression in the endoderm, both hhex and nk2.1a are only required relatively late during thyroid development. In hhex and nk2.1a loss-of-function phenotypes, thyroid development is initiated and arrests only after the primordium has evaginated from the pharyngeal epithelium. Thus, like pax2.1, both hhex and nk2.1a have similarly late roles in differentiation or growth of thyroid follicular cells, and here, we show that all three genes act in parallel rather than in a single pathway. Our functional analysis suggests that these genes have similar roles as in mammalian thyroid development, albeit in a different temporal mode of organogenesis.

  17. Topological materials discovery using electron filling constraints

    NASA Astrophysics Data System (ADS)

    Chen, Ru; Po, Hoi Chun; Neaton, Jeffrey B.; Vishwanath, Ashvin

    2018-01-01

    Nodal semimetals are classes of topological materials that have nodal-point or nodal-line Fermi surfaces, which give them novel transport and topological properties. Despite being highly sought after, there are currently very few experimental realizations, and identifying new materials candidates has mainly relied on exhaustive database searches. Here we show how recent studies on the interplay between electron filling and nonsymmorphic space-group symmetries can guide the search for filling-enforced nodal semimetals. We recast the previously derived constraints on the allowed band-insulator fillings in any space group into a new form, which enables effective screening of materials candidates based solely on their space group, electron count in the formula unit, and multiplicity of the formula unit. This criterion greatly reduces the computation load for discovering topological materials in a database of previously synthesized compounds. As a demonstration, we focus on a few selected nonsymmorphic space groups which are predicted to host filling-enforced Dirac semimetals. Of the more than 30,000 entires listed, our filling criterion alone eliminates 96% of the entries before they are passed on for further analysis. We discover a handful of candidates from this guided search; among them, the monoclinic crystal Ca2Pt2Ga is particularly promising.

  18. Time-Referenced Effects of an Internal vs. External Focus of Attention on Muscular Activity and Compensatory Variability

    PubMed Central

    Hossner, Ernst-Joachim; Ehrlenspiel, Felix

    2010-01-01

    The paralysis-by-analysis phenomenon, i.e., attending to the execution of one's movement impairs performance, has gathered a lot of attention over recent years (see Wulf, 2007, for a review). Explanations of this phenomenon, e.g., the hypotheses of constrained action (Wulf et al., 2001) or of step-by-step execution (Masters, 1992; Beilock et al., 2002), however, do not refer to the level of underlying mechanisms on the level of sensorimotor control. For this purpose, a “nodal-point hypothesis” is presented here with the core assumption that skilled motor behavior is internally based on sensorimotor chains of nodal points, that attending to intermediate nodal points leads to a muscular re-freezing of the motor system at exactly and exclusively these points in time, and that this re-freezing is accompanied by the disruption of compensatory processes, resulting in an overall decrease of motor performance. Two experiments, on lever sequencing and basketball free throws, respectively, are reported that successfully tested these time-referenced predictions, i.e., showing that muscular activity is selectively increased and compensatory variability selectively decreased at movement-related nodal points if these points are in the focus of attention. PMID:21833285

  19. Comparative assessment of genetic and epigenetic variation among regenerants of potato (Solanum tuberosum) derived from long-term nodal tissue-culture and cell selection.

    PubMed

    Dann, Alison L; Wilson, Calum R

    2011-04-01

    Three long-term nodal tissued cultured Russet Burbank potato clones and nine thaxtomin A-treated regenerant lines, derived from the nodal lines, were assessed for genetic and epigenetic (in the form of DNA methylation) differences by AFLP and MSAP. The treated regenerant lines were originally selected for superior resistance to common scab disease and acceptable tuber yield in pot and field trials. The long-term, tissue culture clone lines exhibited genetic (8.75-15.63% polymorphisms) and epigenetic (12.56-26.13% polymorphisms) differences between them and may represent a stress response induced by normal plant growth disruption. The thaxtomin A-treated regenerant lines exhibited much higher significant (p < 0.05) genetic (2-29.38%) and epigenetic (45.22-51.76%) polymorphisms than the nodal cultured parent clones. Methylation-sensitive mutations accumulated within the regenerant lines are significantly correlated (p < 0.05) to disease resistance. However, linking phenotypic differences that could be of benefit to potato growers, to single gene sequence polymorphisms in a tetraploid plant such as the potato would be extremely difficult since it is assumed many desirable traits are under polygenic control.

  20. Theoretical and experimental evidence for a nodal energy gap in MgB2

    NASA Astrophysics Data System (ADS)

    Agassi, Y. Dan; Oates, Daniel E.

    2017-11-01

    We present a phenomenological model that strongly suggests that the smaller of the two energy gaps in MgB2, the so-called π gap, contains nodal lines with a six-fold symmetry (i-wave). The model also indicates that the larger gap, the so-called σ gap, is conventional s-wave. The model is an extension of the BCS gap equation that accounts for the elastic anisotropy in MgB2 and the Coulomb repulsion. It is based on a phononic pairing mechanism and assumes no coupling between the two energy gaps in MgB2 at zero temperature. All of the parameters of the model, such as sound velocities and masses, are independently determined material constants. The results agree with a previous ad-hoc hypothesis that the π energy gap has six nodal lines. That hypothesis was motivated by low-temperature measurements of the surface impedance and intermodulation distortion in high-quality thin films. We briefly review experimental evidence in the literature that is relevant to the energy-gap symmetry. We find that the evidence from the literature for s-wave is inconclusive. Our finding is that the π gap has six nodal lines.

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