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Sample records for achieve negative margins

  1. Negative Stress Margins - Are They Real?

    NASA Technical Reports Server (NTRS)

    Raju, Ivatury S.; Lee, Darlene S.; Mohaghegh, Michael

    2011-01-01

    Advances in modeling and simulation, new finite element software, modeling engines and powerful computers are providing opportunities to interrogate designs in a very different manner and in a more detailed approach than ever before. Margins of safety are also often evaluated using local stresses for various design concepts and design parameters quickly once analysis models are defined and developed. This paper suggests that not all the negative margins of safety evaluated are real. The structural areas where negative margins are frequently encountered are often near stress concentrations, point loads and load discontinuities, near locations of stress singularities, in areas having large gradients but with insufficient mesh density, in areas with modeling issues and modeling errors, and in areas with connections and interfaces, in two-dimensional (2D) and three-dimensional (3D) transitions, bolts and bolt modeling, and boundary conditions. Now, more than ever, structural analysts need to examine and interrogate their analysis results and perform basic sanity checks to determine if these negative margins are real.

  2. Establishing seismic design criteria to achieve an acceptable seismic margin

    SciTech Connect

    Kennedy, R.P.

    1997-01-01

    In order to develop a risk based seismic design criteria the following four issues must be addressed: (1) What target annual probability of seismic induced unacceptable performance is acceptable? (2). What minimum seismic margin is acceptable? (3) Given the decisions made under Issues 1 and 2, at what annual frequency of exceedance should the Safe Shutdown Earthquake ground motion be defined? (4) What seismic design criteria should be established to reasonably achieve the seismic margin defined under Issue 2? The first issue is purely a policy decision and is not addressed in this paper. Each of the other three issues are addressed. Issues 2 and 3 are integrally tied together so that a very large number of possible combinations of responses to these two issues can be used to achieve the target goal defined under Issue 1. Section 2 lays out a combined approach to these two issues and presents three potentially attractive combined resolutions of these two issues which reasonably achieves the target goal. The remainder of the paper discusses an approach which can be used to develop seismic design criteria aimed at achieving the desired seismic margin defined in resolution of Issue 2. Suggestions for revising existing seismic design criteria to more consistently achieve the desired seismic margin are presented.

  3. Negative-Margin Criterion for Impact-Response Prediction

    NASA Astrophysics Data System (ADS)

    Anderson, Denton

    2006-01-01

    Some space missions require a nuclear-power source to generate electrical power to meet mission objectives. At present, the nuclear-power source is an assembly of modular heat sources called the general purpose heat source (GPHS) modules. Each module comprises graphite shells designed to protect iridium-alloy clads which serve as the primary containment shells for the radioactive, heat-producing material. In the course of launching the space vehicle to perform its mission the nuclear heat source may be exposed to severe accident environments. One particular environment is a primary impact event where individual GPHS modules impact hard surfaces at speeds in the range of 50 meters per second or more. Tests have shown that some clads may be breached in particularly severe impacts and release a small fraction of their contents. This paper presents an empirical model for predicting essential ingredients for assessing the risk associated with primary impact events. The ingredients include: clad failure probability, release fraction of clad contents, characterization of the released material in terms of particle-size distribution and a means to estimate uncertainty in the prediction process. The empirical model focuses on the deformation of the clads and their capability to withstand deformation without breaching, measured by ductility. The basic criterion used to estimate all ingredients is called ``negative margin''. The procedure for estimating risk factors entails calculation of clad distortion by, e.g. hydrocode simulation, and high-strain-rate ductility of the iridium alloy. Negative margin is a linear combination of distortion and ductility. Regression equations derived from test data are used to calculate the clad failure probability and the fractional activity release as functions of negative margin. The mass-based particle-size distribution is calculated as a function of release fraction. Cumulative uncertainty in this computing process is evaluated using

  4. Marginalized zero-inflated negative binomial regression with application to dental caries.

    PubMed

    Preisser, John S; Das, Kalyan; Long, D Leann; Divaris, Kimon

    2016-05-10

    The zero-inflated negative binomial regression model (ZINB) is often employed in diverse fields such as dentistry, health care utilization, highway safety, and medicine to examine relationships between exposures of interest and overdispersed count outcomes exhibiting many zeros. The regression coefficients of ZINB have latent class interpretations for a susceptible subpopulation at risk for the disease/condition under study with counts generated from a negative binomial distribution and for a non-susceptible subpopulation that provides only zero counts. The ZINB parameters, however, are not well-suited for estimating overall exposure effects, specifically, in quantifying the effect of an explanatory variable in the overall mixture population. In this paper, a marginalized zero-inflated negative binomial regression (MZINB) model for independent responses is proposed to model the population marginal mean count directly, providing straightforward inference for overall exposure effects based on maximum likelihood estimation. Through simulation studies, the finite sample performance of MZINB is compared with marginalized zero-inflated Poisson, Poisson, and negative binomial regression. The MZINB model is applied in the evaluation of a school-based fluoride mouthrinse program on dental caries in 677 children. PMID:26568034

  5. The Superintendent Beliefs and Leadership Practices in a School District that Has Successfully Increased the Achievement of Traditionally Marginalized Students

    ERIC Educational Resources Information Center

    Fairbanks-Schutz, Jo-Ellen M.

    2010-01-01

    Superintendent leadership can influence student achievement and with the alarming gap between the academic achievement of traditionally marginalized students and their peers, superintendents have an ethical duty to lead their districts in closing these achievement gaps. Spillane, Halverson, and Diamond (2001) suggested that to have a more complete…

  6. Chlamydophila psittaci-negative ocular adnexal marginal zone lymphomas express self polyreactive B-cell receptors.

    PubMed

    Zhu, D; Bhatt, S; Lu, X; Guo, F; Veelken, H; Hsu, D K; Liu, F-T; Alvarez Cubela, S; Kunkalla, K; Vega, F; Chapman-Fredricks, J R; Lossos, I S

    2015-07-01

    The pathogenesis of Chlamydophila psittaci-negative ocular adnexal extranodal marginal zone lymphomas (OAEMZLs) is poorly understood. OAEMZLs are monoclonal tumors expressing a biased repertoire of mutated surface immunoglobulins. Antigenic activation of the B-cell receptor (BCR) may have a role in the pathogenesis of these lymphomas. We have analyzed the reactivity of recombinant OAEMZL immunoglobulins. OAEMZL antibodies reacted with self-human antigens, as demonstrated by enzyme-linked immunosorbent assays, HEp-2 immunofluorescence and human protein microarrays. All the analyzed recombinant antibodies (rAbs) exhibited polyreactivity by comprehensive protein array antibody reactivity and some rAbs also demonstrated rheumatoid factor activity. The identity of several reactive antigens was confirmed by microcapillary reverse-phase high-performance liquid chromatography nano-electrospray tandem mass spectrometry. The tested rAbs frequently reacted with shared intracellular and extracellular self-antigens (for example, galectin-3). Furthermore, these self-antigens induced BCR signaling in B cells expressing cognate surface immunoglobulins derived from OAEMZLs. These findings indicate that interactions between self-antigens and cognate OAEMZL tumor-derived BCRs are functional, inducing intracellular signaling. Overall, our findings suggest that self-antigen-induced BCR stimulation may be implicated in the pathogenesis of C. psittaci-negative OAEMZLs. PMID:25676418

  7. Molecular and Genomic Aberrations in Chlamydophila psittaci Negative Ocular Adnexal Marginal Zone Lymphomas

    PubMed Central

    Zhu, Daxing; Ikpatt, Offiong F; Dubovy, Sander R; Lossos, Chen; Natkunam, Yasodha; Chapman-Fredricks, Jennifer R.; Fan, Yao-Shan; Lossos, Izidore S.

    2013-01-01

    The etiology and pathogenesis of ocular adnexal extranodal marginal zone lymphoma (OAEMZL) are still unknown and the association with Chlamydophila psittaci (C. psittaci) has been shown in only some geographic regions. Herein we comprehensively examined the frequency of chromosomal translocations as well as CARD11, MYD88 (L265P) and A20 mutations /deletions in 45 C. psittaci negative OAEMZLs. t(14;18)(q32;q21) IGH-MALT1 and t(11;18)(q21;q21) API2-MALT1 were not detected in any of the analyzed tumors while 3 tumors harbored IGH translocations to an unidentified partner. CARD11 mutations were not found in all the analyzed tumors while MYD88 L265P mutation was detected in 3 (6.7%) tumors. A20 mutations and deletions were each detected in 7(15.6%) and 6(13.3%) of the tumors, respectively. Therefore, the observed genetic aberrations could account for the activation of NF-kB signaling pathway in only a minority of the cases. Further studies are needed to identify the molecular mechanisms underlying the pathogenesis of OAEMZL. PMID:23720088

  8. Associations of Future Expectations, Negative Friends, and Academic Achievement in High-Achieving African American Adolescents

    ERIC Educational Resources Information Center

    Cunningham, Michael; Corprew, Charles S., III; Becker, Jonathan E.

    2009-01-01

    The relations of future expectations (general and academic) to academic outcomes were examined in a sample of 129 African American high-achieving adolescents (majority female participants, n = 92). This study was interested in the multidimensional nature of future expectations. Results from the study confirm the hypothesis that academic future…

  9. The Effects of Achieved National Board for Professional Teaching Standards Certification on the Marginality of Physical Education Teachers

    ERIC Educational Resources Information Center

    Gaudreault, Karen Lux; Woods, Amelia Mays

    2012-01-01

    The purpose of the study was to examine the relationship between achieving The National Board for Professional Teaching Standards certification and feelings of marginality of physical education teachers. Data sources included a focus group interview with 6 National Board Certified Physical Education Teachers (NBCPETs) and individual phone…

  10. Do marginal investments made by NHS healthcare commissioners in the UK produce the outcomes they hope to achieve? Observational study

    PubMed Central

    O'Cathain, Alicia; Sampson, Fiona; Strong, Mark; Pickin, Mark; Goyder, Elizabeth; Dixon, Simon

    2015-01-01

    Objective To investigate the effect of targeted marginal annual investments by local healthcare commissioners on the outcomes they expected to achieve with these investments. Design Controlled before and after study. Setting: 152 commissioning organisations (primary care trusts) in England. Methods National surveys of commissioning managers in 2009 and 2010 to identify: the largest marginal investments made in four key conditions/services (diabetes, coronary heart disease, chronic pulmonary airways disease and emergency and urgent care) in 2008/2009 and 2009/2010; the outcomes commissioners expected to achieve with these investments; and the processes commissioners used to develop these investments. Collation of routinely available data on outcomes commissioners expected from these investments over the period 2007/2008 to 2010/2011. Results 51% (77/152) of commissioners agreed to participate in the survey in 2009 and 60% (91/152) in 2010. Around half reported targeted marginal investments in each condition/service each year. Routine data on many of the outcomes they expected to achieve through these investments were not available. Also, commissioners expected some outcomes to be achieved beyond the time scale of our study. Therefore, only a limited number of outcomes of investments were tested. Outcomes included directly standardised emergency admission rates for the four conditions/services, and the percentage of patients with diabetes with glycated haemoglobin <7. There was no evidence that targeted marginal investments reduced emergency admission rates. There was evidence of an improvement in blood glucose management for diabetes for commissioners investing to improve diabetes care but this was compromised by a change in how the outcome was measured in different years. This investment was unlikely to be cost-effective. Conclusions Commissioners made marginal investments in specific health conditions and services with the aim of improving a wide range of outcomes

  11. Methodology for determining elevon deflections to trim and maneuver the DAST vehicle with negative static margin

    NASA Technical Reports Server (NTRS)

    Perry, B., III

    1982-01-01

    The relationships between elevon deflection and static margin using elements from static and dynamic stability and control and from classical control theory are emphasized. Expressions are derived and presented for calculating elevon deflections required to trim the vehicle in lg straight-and-level flight and to perform specified longitudinal and lateral maneuvers. Applications of this methodology are made at several flight conditions for the ARW-2 wing. On the basis of these applications, it appears possible to trim and maneuver the vehicle with the existing elevons at -15% static margin.

  12. Negative School Factors and Their Influence on Math and Science Achievement in TIMSS 2003

    ERIC Educational Resources Information Center

    Perse, Tina Vrsnik; Kozina, Ana; Leban, Tina Rutar

    2011-01-01

    The aim of the present study was to conduct an analysis of TIMSS (Trends in International Mathematics and Science Study) 2003 database and to determine how negative school factors, such as aggression, are associated to the mathematical and science achievement of students. The analyses were conducted separately for national and international data.…

  13. Differential negative air ion effects on learning disabled and normal-achieving children

    NASA Astrophysics Data System (ADS)

    Morton, L. L.; Kershner, J. R.

    1990-03-01

    Forty normal-achieving and 33 learning disabled (LD) children were assigned randomly to either a negative ion or placebo test condition. On a dichotic listening task using consonant-vowel (CV) combinations, both groups showed an ioninduced increase in the normal right ear advantage (REA). However, the mechanisms for this effect were different for each group. The LDs showed the effect at the right ear/left hemisphere (enhancement). The normal achievers showed the effect at the left ear/right hemisphere (inhibition). The results are consistent with an activation-inhibition model of cerebral function and suggest a functional relationship between arousal, interhemispheric activation-inhibition, and learning disabilities. The LDs may have an interhemispheric dysfunction. Both groups showed superior right ear report and the normal achiever showed overall superiority. Normal achievers showed higher consonant intrusion scores, probably due to a greater cognitive capacity. Age was a significant covariate reflecting developmental capacity changes. Negative air ions are seen to be a tool with potential theoretical and remedial applications.

  14. Can we bet on negative emissions to achieve the 2°C target even under strong carbon cycle feedbacks?

    NASA Astrophysics Data System (ADS)

    Tanaka, K.; Yamagata, Y.; Yokohata, T.; Emori, S.; Hanaoka, T.

    2015-12-01

    Negative emission technologies such as Bioenergy with Carbon dioxide Capture and Storage (BioCCS) play an ever more crucial role in meeting the 2°C stabilization target. However, such technologies are currently at their infancy and their future penetrations may fall short of the scale required to stabilize the warming. Furthermore, the overshoot in the mid-century prior to a full realization of negative emissions would give rise to a risk because such a temporal but excessive warming above 2°C might amplify itself by strengthening climate-carbon cycle feedbacks. It has not been extensively assessed yet how carbon cycle feedbacks might play out during the overshoot in the context of negative emissions. This study explores how 2°C stabilization pathways, in particular those which undergo overshoot, can be influenced by carbon cycle feedbacks and asks their climatic and economic consequences. We compute 2°C stabilization emissions scenarios under a cost-effectiveness principle, in which the total abatement costs are minimized such that the global warming is capped at 2°C. We employ a reduced-complexity model, the Aggregated Carbon Cycle, Atmospheric Chemistry, and Climate model (ACC2), which comprises a box model of the global carbon cycle, simple parameterizations of the atmospheric chemistry, and a land-ocean energy balance model. The total abatement costs are estimated from the marginal abatement cost functions for CO2, CH4, N2O, and BC.Our preliminary results show that, if carbon cycle feedbacks turn out to be stronger than what is known today, it would incur substantial abatement costs to keep up with the 2°C stabilization goal. Our results also suggest that it would be less expensive in the long run to plan for a 2°C stabilization pathway by considering strong carbon cycle feedbacks because it would cost more if we correct the emission pathway in the mid-century to adjust for unexpectedly large carbon cycle feedbacks during overshoot. Furthermore, our

  15. Achievement Goal Orientations and Self Handicapping as Mediator and Moderator of the Relationship between Intrinsic Achievement Motivation and Negative Automatic Thoughts in Adolescence Students

    ERIC Educational Resources Information Center

    Kapikiran, Sahin

    2012-01-01

    The main purpose of this study was to examine the mediator and moderator role of self-handicapping and achievement goal orientations variables on the relationship between negative automatic thoughts intrinsic achievement motivation in high school students. 586 high school students, ranging in age from 14 to 20 (M = 16.08), adolescence students…

  16. Study on personality dimension negative emotionality affecting academic achievement among Malaysian medical students studying in Malaysia and overseas

    PubMed Central

    Bhagat, Vidya; Haque, Mainul; Simbak, Nordin Bin; Jaalam, Kamarudin

    2016-01-01

    Personality dimension negative emotionality is known to be associated with academic achievement. The present study focuses on the influence of negative emotionality (neuroticism) on the medical students’ academic achievements. The main objective of this study was to ascertain the negative emotionality scores among the first year Malaysian medical students studying in Malaysia and India, further to find out the association between negative emotionality and their academic achievements. The current study sample includes 60 first year Malaysian medical students from Universiti Sultan Zainal Abidin, Malaysia, and USM-KLE IMP, Belgaum, India. They were selected by convenient sampling technique. The Medico-Psychological questionnaire was used to find out the negative emotionality scores among the students and these scores were compared with academic scores. The data were analyzed using SPSS- 20. Thus, the study result goes with the prediction that there is a significant correlation between academic achievement and negative emotionality. We concluded that negative emotionality has a negative impact on medical student’s academic achievement regardless of the fact whether they study in their own country or overseas. PMID:27354836

  17. Longitudinal relations among parents' reactions to children's negative emotions, effortful control, and math achievement in early elementary school.

    PubMed

    Swanson, Jodi; Valiente, Carlos; Lemery-Chalfant, Kathryn; Bradley, Robert H; Eggum-Wilkens, Natalie D

    2014-01-01

    Panel mediation models and fixed-effects models were used to explore longitudinal relations among parents' reactions to children's displays of negative emotions, children's effortful control (EC), and children's math achievement (N = 291; M age in fall of kindergarten = 5.66 years, SD = .39 year) across kindergarten through second grade. Parents reported their reactions and children's EC. Math achievement was assessed with a standardized achievement test. First-grade EC mediated the relation between parents' reactions at kindergarten and second-grade math achievement, beyond stability in constructs across study years. Panel mediation model results suggested that socialization of EC may be one method of promoting math achievement in early school; however, when all omitted time-invariant covariates of EC and math achievement were controlled, first-grade EC no longer predicted second-grade math achievement. PMID:24916765

  18. Sex Differences in the Meaning of Negative Evaluation in Achievement Situations: Determinants and Consequences.

    ERIC Educational Resources Information Center

    Dweck, Carol S.

    Sex differences in children's reactions to failure feedback in school situations were investigated by assessing the ways in which teachers use negative evaluation in the classroom. Three aspects of teachers' evaluative feedback were studied: (1) ratio of negative to positive feedback; (2) contingency vs. noncontingency of feedback; and (3) (the…

  19. The Positive and Negative Syndrome Scale (PANSS): A Three-Factor Model of Psychopathology in Marginally Housed Persons with Substance Dependence and Psychiatric Illness

    PubMed Central

    Giesbrecht, Chantelle J.; O’Rourke, Norm; Leonova, Olga; Strehlau, Verena; Paquet, Karine; Vila-Rodriguez, Fidel; Panenka, William J.; MacEwan, G. William; Smith, Geoffrey N.; Thornton, Allen E.; Honer, William G.

    2016-01-01

    Rates of psychopathology are elevated in marginalized and unstably housed persons, underscoring the need for applicable clinical measures for these populations. The Positive and Negative Syndrome Scale (PANSS) is a clinical instrument principally developed for use in schizophrenia to identify the presence and severity of psychopathology symptoms. The current study investigates whether a reliable and valid PANSS factor structure emerges in a marginally housed, heterogeneous sample recruited from the Downtown Eastside of Vancouver where substance use disorders and psychiatric illness are pervasive. Participants (n = 270) underwent structured clinical assessments including the PANSS and then were randomly assigned to either exploratory (EFA) or confirmatory factor analytic (CFA) subsamples. EFA pointed to a novel three factor PANSS. This solution was supported by CFA. All retained items (28 out of 30) load significantly upon hypothesized factors and model goodness of fit analyses are in the acceptable to good range. Each of the three first-order factor constructs, labeled Psychosis/Disorganized, Negative Symptoms/Hostility, and Insight/Awareness, contributed significantly to measurement of a higher-order psychopathology construct. Further, the latent structure of this 3-factor solution appears temporally consistent over one-year. This PANSS factor structure appears valid and reliable for use in persons with multimorbidity, including substance use disorders. The structure is somewhat distinct from existing solutions likely due to the unique characteristics of this marginally housed sample. PMID:26999280

  20. Differences in Teachers' Perceptions of the Causes of Positive Versus Negative Student Achievement Outcomes.

    ERIC Educational Resources Information Center

    Guskey, Thomas R.

    Past research on teachers' causal attributions has shown little relation between perceptions of responsibility for positive versus negative student learning outcomes. In this study, Weiner's model for causal attributions was employed to explore these perceived attributional differences. Data were gathered from 184 teachers from two metropolitan…

  1. Boundary scavenging at the East Atlantic margin does not negate use of 231Pa/230Th to trace Atlantic overturning

    NASA Astrophysics Data System (ADS)

    Lippold, Jörg; Mulitza, Stefan; Mollenhauer, Gesine; Weyer, Stefan; Heslop, David; Christl, Marcus

    2012-06-01

    The 231Pa/230Th method is a promising tool to reconstruct Ocean circulation over the past Glacial-Interglacial cycle. However, marine particle flux may constrain the applicability of this ratio as a direct quantitative proxy for the strength of Atlantic Meridional Overturning Circulation (AMOC) by influencing the fractionation between the in situ produced 231Pa and 230Th in ocean water. Here we present 231Pa/230Th down-core profiles from high particle flux areas off Namibia and Senegal covering the past ∼35 ka. The 231Pa/230Th profiles at these sites show very different responses to temporal variations of particle fluxes and to changes in water masses. Our results show that sedimentary 231Pa/230Th in the Eastern Atlantic margin is linked to particle flux, but controlled primarily by the mode of the AMOC. Our data suggest that during the past ∼30 ka the high productivity Eastern margin was not capable of importing and storing significant amounts of 231Pa from the open Ocean. Consequently, the applicability of the 231Pa/230Th proxy to reconstruct past ocean circulation is not hampered by this potentially additional 231Pa sink.

  2. Family Inequality, School Inequalities, and Mathematics Achievement in 65 Countries: Microeconomic Mechanisms of Rent Seeking and Diminishing Marginal Returns

    ERIC Educational Resources Information Center

    Chiu, Ming Ming

    2015-01-01

    Background/Context: While many studies show that greater economic inequality widens the achievement gap between rich and poor students, recent studies indicate that countries with greater economic inequality have lower overall student achievement. Purpose/Objective/Research Question/Focus of Study: This study explores whether family inequalities…

  3. Consequences of the Confucian Culture: High Achievement but Negative Psychological Attributes?

    ERIC Educational Resources Information Center

    Ho, Irene T.; Hau, Kit-Tai

    2010-01-01

    In "Unforgiving Confucian culture: A breeding ground for high academic achievement, test anxiety and self-doubt?" Stankov (in press) provides three reasons for caution against over-glorifying the academic excellence of Confucian Asian learners, namely that it may lead to a reluctance to change their rote learning approach which is not conducive to…

  4. Negative Relationship between Achievement in High School and Self-Concept in College.

    ERIC Educational Resources Information Center

    Wolfe, Raymond N.; Grosch, James W.

    Social learning theory implies that there should be a significant positive relationship between academic performance and self-concept and outcomes of recent meta-analyses support this prediction. While path-analytic studies of high school samples in the 1960s and 1970s demonstrated that ability and achievement each made a small positive…

  5. Effect of Artificial Pitch Damping on the Longitudinal and Rolling Stability of Aircraft with Negative Static Margins

    NASA Technical Reports Server (NTRS)

    Moul, Martin T.; Brown, Lawrence W.

    1959-01-01

    A preliminary theoretical investigation has been made of the short-period longitudinal and steady-rolling (inertia coupling) stability of a hypersonic glider configuration for center-of-gravity locations rear-ward of the airplane neutral point. Such center-of-gravity positions for subsonic flight would improve performance by reducing supersonic and hypersonic static margins and trim drag. Results are presented of stability calculations and a simulator study for a velocity of 700 ft/sec and an altitude of 401,000 feet. With no augmentation, the airplane was rapidly divergent and was considered unsatisfactory in the simulator study. When a pitch damper was employed as a stability augmenter, the short-period mode became overdamped, and the airplane was easily controlled on the simulator. A steady-rolling analysis showed that the airplane can be made free of rolling divergence for all roll rates with an appropriate damper gain.

  6. Surgical resection margins after breast-conserving surgery: Senonetwork recommendations.

    PubMed

    Galimberti, Viviana; Taffurelli, Mario; Leonardi, Maria Cristina; Aristei, Cynthia; Trentin, Chiara; Cassano, Enrico; Pietribiasi, Francesca; Corso, Giovanni; Munzone, Elisabetta; Tondini, Carlo; Frigerio, Alfonso; Cataliotti, Luigi; Santini, Donatella

    2016-06-01

    This paper reports findings of the "Focus on Controversial Areas" Working Party of the Italian Senonetwork, which was set up to improve the care of breast cancer patients. After reviewing articles in English on the MEDLINE system on breast conserving surgery for invasive carcinoma, the Working Party presents their recommendations for identifying risk factors for positive margins, suggests how to manage them so as to achieve the highest possible percentage of negative margins, and proposes standards for investigating resection margins and therapeutic approaches according to margin status. When margins are positive, approaches include re-excision, mastectomy, or, as second-line treatment, radiotherapy with a high boost dose. When margins are negative, boost administration and its dose depend on the risk of local recurrence, which is linked to biopathological tumor features and surgical margin width. Although margin status does not affect the choice of systemic therapy, it may delay the start of chemotherapy when further surgery is required. PMID:27103209

  7. The negative influence of significant others on high academic achieving school pupils' choice of nursing as a career.

    PubMed

    Neilson, Gavin R; McNally, Jim

    2013-03-01

    The International Council of Nurses proposes that the shortage of nurses is global in scale and is expected to become much worse in the years ahead. A major factor impacting on the worldwide nursing shortage is the diminishing number of young people choosing nursing as a career (International Council of Nurses, 2008). One important dimension of the school pupils' career choice process is their interactions with significant others and the influence of these significant others (Hodkinson and Sparkes, 1997). As Schools/Departments of Nursing endeavour to attract more intellectual school leavers it is important to examine what advice and opinions are significant others giving regarding nursing as a career choice and how influential is this advice. This paper is based on interview data from 20 high academic achieving 5th and 6th year school pupils in Scotland, paradigmatic cases from a larger sample, who had considered nursing as a possible career choice within their career preference cluster, but then later disregarded nursing and decided to pursue medicine or another health care profession. The data was particularly striking in revealing the negative influence of significant others on high academic achieving school pupils' choice of nursing as a career. The influence of significant others, these being specifically parents, guardians, guidance teachers and career advisors was very apparent in the data in that they had a very negative view regarding nursing as a career choice for high academic achieving school pupils. PMID:22464633

  8. Impact of Margin Assessment Method on Positive Margin Rate and Total Volume Excised

    PubMed Central

    Moo, Tracy-Ann; Choi, Lydia; Culpepper, Candice; Olcese, Cristina; Heerdt, Alexandra; Sclafani, Lisa; King, Tari A.; Reiner, Anne S.; Patil, Sujata; Brogi, Edi; Morrow, Monica; Van Zee, Kimberly J.

    2014-01-01

    Background For breast-conserving surgery (BCS), the method of margin assessment that most frequently achieves negative margins without increasing volume of tissue excised is uncertain. We examined our institutional experience with 3 different margin assessment methods used by 6 experienced breast surgeons. Methods Patients undergoing BCS for invasive carcinoma during July-December of a representative year during which each method was performed (Perpendicular, 2003; Tangential, 2004; Cavity-Shave, 2011) were included. Effect of margin method on positive margin rate at first excision, and total volume excised to achieve negative margins, were evaluated by multivariable analysis, by surgeon, and by tumor size and presence of extensive intraductal component (EIC). Results 555 patients were identified: Perpendicular, 140; Tangential, 124; Cavity-Shave, 291. Tangential method had a higher rate of positive margins at first excision than Perpendicular and Cavity-Shave methods (49%, 15%, 11%, respectively; p<0.0001). Median volumes to achieve negative margins were similar (55ml, Perpendicular; 64ml Tangential; 62ml Cavity-Shave, p=0.24). Four of 6 surgeons had the lowest rate of positive margins with Cavity-Shave method—significant when compared to Tangential (p<0.0001), but not Perpendicular (p=0.37). Comparison of volume excised using the 3 methods was variable by surgeon (p<0.0001). Perpendicular method was optimal for T1 tumors without EIC; Cavity-Shave tended to be superior for T2/3 tumors and/or EIC. Conclusions While the Cavity-Shave method may decrease rates of positive margins, its effect on volume is variable among surgeons and may result in an increase in total volume excised for some surgeons, and for small tumors without EIC. PMID:24046114

  9. Female Special Education Directors: Doubly Marginalized.

    ERIC Educational Resources Information Center

    Keefe, Charlotte Hendrick; Parmley, Pamela

    2003-01-01

    A qualitative study of five Texas female special education directors found that although participants achieved an administrative position, they were marginalized due to their leadership style, gender discrimination, and socialization. Participants also indicated a negative connection between being in special education administration and top-level…

  10. Defining and Assessing Parent Empowerment and Its Relationship to Academic Achievement Using the National Household Education Survey: A Focus on Marginalized Parents

    ERIC Educational Resources Information Center

    Kim, Jungnam

    2012-01-01

    Marginalized parents experience multiple and complex challenges in terms of social isolation, exclusion, and powerlessness. This empirical study investigated the effects of parent empowerment on academic outcomes using a large national representative sample and should provide insights about the importance of parent empowerment in education and…

  11. On achieving element-wise species balance and enforcing non-negative constraint for advection-diffusion-reaction equations

    NASA Astrophysics Data System (ADS)

    Mudunuru, M. K.; Nakshatrala, K.

    2012-12-01

    Advection-Diffusion-Reaction (ADR) equations naturally arises in many physical phenomena, which include seepage of contaminants in heterogeneous porous media, transport of injected tracers due to the flow of oil in a petroleum reservoir, and degradation of a deformable solid due to diffusing chemical species. Vast literature exists on how to solve this equation in the cases when the medium is isotropic, velocity field being divergence free, and for advection-dominated problems. However, it is well know that many popular finite element formulations (e.g., the standard Galerkin formulation, stabilized methods, variational multi-scale methods, subgrid-scale methods, and primitive least-squares formulations) do not satisfy element-by-element mass/species balance and do not produce non-negative solutions on general computational grids. Various post-processing based methods were developed in order to recover some properties of computed numerical solutions. Most of these post-processing techniques are ad hoc, and are not variationally consistent. In this poster, we shall present a novel numerical methodology for ADR equations that satisfy discrete maximum principles, the non-negative constraint, and element-by-element mass/species balance. The methodology can handle general computational grids, no additional restrictions on time-step, and for heterogeneous anisotropic media. Several numerical results pertinent to advection-dominated ADR problems will be presented to illustrate the performance of the proposed numerical formulation.

  12. Dissociable medial frontal negativities from a common monitoring system for self- and externally caused failure of goal achievement.

    PubMed

    Gentsch, Antje; Ullsperger, Peter; Ullsperger, Markus

    2009-10-01

    Goal-directed behavior requires the ability to adapt performance strategies based on the attribution of unintended outcomes to internal or external causes. Using event-related brain potentials, the present research compared neural activity following self-generated errors induced by a flanker task and following externally generated errors induced by supposed "technical malfunctions". Errors and malfunctions were associated with temporally dissociable ERP components, the short-latency error-related negativity (ERN) and the longer-latency feedback-related negativity (FRN), respectively. Independent component analysis (ICA) was applied to compare the underlying neural components of ERN and FRN. ICA results revealed that the FRN is attributable to the neural sources of the ERN, suggesting that the two components share a source network. Furthermore, single-trial amplitudes of ERN and FRN were specifically related to the implementation of error correction and malfunction compensation: the stronger the failure signal, the more efficient was remedial behavior. Together the results demonstrate that internally and externally generated unintended action outcomes engage a common monitoring mechanism that manifests in two temporally distinct ERP components and induces similar compensatory processes. The temporal dissociation of the ERP components might provide the basis for further processes of outcome attribution underlying action selection and changes in performance strategy. In line with recent neuroimaging findings, ERN and FRN appear to reflect the use of different sources of information about action outcome to update action value. PMID:19486945

  13. Assessment of Margins in Transoral Laser and Robotic Surgery

    PubMed Central

    Hamzany, Yaniv; Brasnu, Daniel; Shpitzer, Thomas; Shvero, Jacob

    2014-01-01

    The growing practice of endoscopic surgery has changed the therapeutic management of selected head and neck cancers. Although a negative surgical margin in resection of neoplasm is the most important surgical principle in oncologic surgery, controversies exist regarding assessment and interpretation of the status of margin resection. The aim of this review was to summarize the literature considering the assessment and feasibility of negative margins in transoral laser microsurgery (TLM) and transoral robotic surgery (TORS). Free margin status is being approached differently in vocal cord cancer (1–2 mm) compared with other sites in the upper aerodigestive tract (2–5 mm). Exposure, orientation of the pathological specimen, and co-operation with the pathologist are crucial principles needed to be followed in transoral surgery. Piecemeal resection to better expose deep tumor involvement and biopsies taken from surgical margins surrounding site of resection can improve margin assessment. High rates of negative surgical margins can be achieved with TLM and TORS. Adjuvant treatment decision should take into consideration also the surgeon’s judgment with regard to the completeness of tumor resection. PMID:24808954

  14. Longitudinal Relations among Parents' Reactions to Children's Negative Emotions, Effortful Control, and Math Achievement in Early Elementary School

    ERIC Educational Resources Information Center

    Swanson, Jodi; Valiente, Carlos; Lemery-Chalfant, Kathryn; Bradley, Robert H.; Eggum-Wilkens, Natalie D.

    2014-01-01

    Panel mediation models and fixed-effects models were used to explore longitudinal relations among parents' reactions to children's displays of negative emotions, children's effortful control (EC), and children's math achievement (N = 291; M age in fall of kindergarten = 5.66 years, SD = 0.39 year) across kindergarten through…

  15. Examining a negative halo effect to anabolic steroids users through perceived achievement goals, sportspersonship orientations, and aggressive tendencies.

    PubMed

    Chantal, Yves; Bernache-Assollant, Iouri; Schiano-Lomoriello, Sandrine

    2013-04-01

    We investigated the social image of anabolic steroids (AS) users grounding our analysis on the achievement goal theory of Nicholls. Our main goal was to explore how an athlete's acceptance of AS use would impact on the way that athlete will be perceived by others. Non-AS-using participants reacted to one of two scenarios portraying a male athlete either accepting or refusing to engage in drug use behavior. The results suggested that the acceptance of anabolic steroids yielded an unfavorable social image--perceivers inferred a predominant ego orientation to characterize the AS-user's motivation as well as weaker sportspersonship and a stronger proclivity for reactive aggression than instrumental aggression. Moreover, the analyses did not yield significant gender or interaction effects. Finally, those findings are commented in view of methodological shortcomings and of the perspectives that they may offer for future research concerning the motivational aspects of the social perceptions of drug use in sport. PMID:23301931

  16. Sensitivity improvement of an electrical sensor achieved by control of biomolecules based on the negative dielectrophoretic force.

    PubMed

    Kim, Hye Jin; Kim, Jinsik; Yoo, Yong Kyoung; Lee, Jeong Hoon; Park, Jung Ho; Hwang, Kyo Seon

    2016-11-15

    Effective control of nano-scale biomolecules can enhance the sensitivity and limit of detection of an interdigitated microelectrode (IME) sensor. Manipulation of the biomolecules by dielectrophoresis (DEP), especially the negative DEP (nDEP) force, so that they are trapped between electrodes (sensing regions) was predicted to increase the binding efficiency of the antibody and target molecules, leading to a more effective reaction. To prove this concept, amyloid beta 42 (Aβ42) and prostate specific antigen (PSA) protein were respectively trapped between the sensing region owing to the nDEP force under 5V and 0.05V, which was verified with COMSOL simulation. Using the simulation value, the resistance change (ΔR/Rb) of the IME sensor from the specific antibody-antigen reaction of the two biomolecules and the change in fluorescence intensity were compared in the reference (pDEP) and nDEP conditions. The ΔR/Rb value improved by about 2-fold and 1.66-fold with nDEP compared to the reference condition with various protein concentrations, and these increases were confirmed with fluorescence imaging. Overall, nDEP enhanced the detection sensitivity for Aβ42 and PSA by 128% and 258%, respectively, and the limit of detection improved by up to 2-orders of magnitude. These results prove that DEP can improve the biosensor's performance. PMID:27449966

  17. Intraoperative Evaluation of Breast Tumor Margins with Optical Coherence Tomography

    PubMed Central

    Nguyen, Freddy T.; Zysk, Adam M.; Chaney, Eric J.; Kotynek, Jan G.; Oliphant, Uretz J.; Bellafiore, Frank J.; Rowland, Kendrith M.; Johnson, Patricia A.; Boppart, Stephen A.

    2009-01-01

    As breast cancer screening rates increase, smaller and more numerous lesions are being identified earlier, leading to more breast-conserving surgical procedures. Achieving a clean surgical margin represents a technical challenge with important clinical implications. Optical coherence tomography (OCT) is introduced as an intraoperative high-resolution imaging technique that assesses surgical breast tumor margins by providing real-time microscopic images up to 2 mm beneath the tissue surface. In a study of 37 patients split between training and study groups, OCT images covering 1 cm2 regions were acquired from surgical margins of lumpectomy specimens, registered with ink, and correlated with corresponding histological sections. A 17 patient training set used to establish standard imaging protocols and OCT evaluation criteria demonstrated that areas of higher scattering tissue with a heterogeneous pattern were indicative of tumor cells and tumor tissue, in contrast to lower scattering adipocytes found in normal breast tissue. The remaining 20 patients were enrolled into the feasibility study. Of these lumpectomy specimens, 11 were identified with a positive or close surgical margin and 9 were identified with a negative margin under OCT. Based on histological findings, 9 true positives, 9 true negatives, 2 false positives, and 0 false negatives were found, yielding a sensitivity of 100% and specificity of 82%. These results demonstrate the potential of OCT as a real-time method for intraoperative margin assessment in breast conserving surgeries. PMID:19910294

  18. [Prolonged remission achieved by using bevacizumab plus paclitaxel therapy combined with sequential radiotherapy for a rapidly growing chest wall recurrence of triple negative breast cancer - a case report].

    PubMed

    Kawashima, Masahiro; Fujii, Kazuhiro; Kiso, Marina; Takeyama, Osamu; Kan, Shugen; Tanaka, Mitsuru

    2015-01-01

    A 73-year-old woman, who was diagnosed with right triple negative breast cancer (cT1cN1M0, stage I ) and underwent right modified radical mastectomy with axillary lymph node dissection, showed recurrent disease in the right parasternal lymph node 4 years after the operation. Computed tomography (CT) revealed rapid growth of the tumor along with pain, accompanied by the destruction of the sternal bone. Five cycles of bevacizumab plus paclitaxel (BEV+wPTX) treatment (10 mg/kg of bevacizumab on days 1 and 15 plus 90 mg/m² of paclitaxel on days 1, 8, and 15 every 4 weeks)achieved remarkable tumor regression. Parasternal irradiation (30 Gy/15 Fr) followed by oral capecitabine treatment (600 mg b. i. d; 3 week administration followed by a week of rest) as maintenance therapy showed complete tumor regression and helped to achieve good quality of life (QOL) without any unfavorable symptoms at the 2-year follow-up, although the estimated progression free survival of this treatment is about 6 months. As BEV+wPTX had a high response rate for recurrent breast cancer, its combination with sequential radiotherapy could provide a favorable local control rate and good QOL for patients with rapidly growing, solitary, recurrent breast cancers. PMID:25596684

  19. Social Marginality, Academic Achievement and Vocational Development.

    ERIC Educational Resources Information Center

    Madhere, Serge

    Human capital theorists suggest that education is a form of investment in the individual's future which yields economic dividends commensurate to the investment. Another school of thought criticizes this theory for not showing the relationship between schooling, productivity, and earnings, and holds that for minority workers, program completion…

  20. Can Parental Expectations Compensate for the Negative Effects of Low-Birth Weight on Academic Achievement? A Cross-Sectional Analysis of the National PEELS Data

    ERIC Educational Resources Information Center

    Cormier-Zenon, Dolores E.

    2012-01-01

    The purpose of this study is to examine the potential impact parental expectations have on the academic achievement of children born with low-birth weight to inform educational leaders. Literature on levels of children born with birth weights as low as 1 LB to as high as 9 LBS were evaluated based on: birth weight, academic achievement, and…

  1. From Marginalization to Integrated Language Minority Education.

    ERIC Educational Resources Information Center

    de Jong, Ester J.

    It is argued that language minority education has generally been perceived as a separate program or model, and as a result has often become marginalized within its larger school setting, which negatively influences students, teachers, and the program. An alternative approach to program design, intended to avoid this marginalization by making…

  2. Benign and low-grade fibroepithelial neoplasms of the breast have low recurrence rate after positive surgical margins.

    PubMed

    Cowan, Morgan L; Argani, Pedram; Cimino-Mathews, Ashley

    2016-03-01

    Breast phyllodes tumors are uncommon fibroepithelial neoplasms with a range of histologic features. Surgical excision is the primary management, but the need for excision to negative margins in benign and borderline phyllodes tumors is unclear. Here, we review the surgical management patterns and outcomes of 90 patients with benign and low-grade fibroepithelial lesions of the breast treated at our institution, including 19 borderline phyllodes tumors, 52 benign phyllodes tumors, and 19 representative neoplasms with overlapping features of fibroadenoma and benign phyllodes tumors, which were classified as 'fibroadenomas with phyllodal features'. In total, 52 (58%) had positive surgical margins on first excision, and of these 17 (33%) underwent re-excision to achieve negative margins. Residual tumor was identified in three (18%) re-excisions. Patients with fibroadenoma with phyllodal features were more likely to have a positive surgical margin than with benign phyllodes tumors or borderline phyllodes tumors (89 vs 49%, P=0.0015), and were less likely to undergo re-excision for positive margins (12 vs 43%, P=0.031). In total, there were three recurrences (3%), with one per fibroadenoma with phyllodal features, benign phyllodes tumor, and borderline phyllodes tumor. There was no statistically significant difference in recurrence rates between patients with positive or negative margins, or between patients with positive margin with or without re-excision. The extent of the positive margin did not predict recurrence. In conclusion, the recurrence rate of benign and low-grade fibroepithelial lesions is low and not associated with the original margin status. Patients with fibroadenomas with phyllodal features, benign phyllodes tumors, or selected borderline phyllodes tumors and positive margins on initial excision may be managed conservatively, with close follow-up and timely re-excision of any potential recurrence. PMID:26743469

  3. Determination of all feasible robust PID controllers for open-loop unstable plus time delay processes with gain margin and phase margin specifications.

    PubMed

    Wang, Yuan-Jay

    2014-03-01

    This paper proposes a novel alternative method to graphically compute all feasible gain and phase margin specifications-oriented robust PID controllers for open-loop unstable plus time delay (OLUPTD) processes. This method is applicable to general OLUPTD processes without constraint on system order. To retain robustness for OLUPTD processes subject to positive or negative gain variations, the downward gain margin (GM(down)), upward gain margin (GM(up)), and phase margin (PM) are considered. A virtual gain-phase margin tester compensator is incorporated to guarantee the concerned system satisfies certain robust safety margins. In addition, the stability equation method and the parameter plane method are exploited to portray the stability boundary and the constant gain margin (GM) boundary as well as the constant PM boundary. The overlapping region of these boundaries is graphically determined and denotes the GM and PM specifications-oriented region (GPMSOR). Alternatively, the GPMSOR characterizes all feasible robust PID controllers which achieve the pre-specified safety margins. In particular, to achieve optimal gain tuning, the controller gains are searched within the GPMSOR to minimize the integral of the absolute error (IAE) or the integral of the squared error (ISE) performance criterion. Thus, an optimal PID controller gain set is successfully found within the GPMSOR and guarantees the OLUPTD processes with a pre-specified GM and PM as well as a minimum IAE or ISE. Consequently, both robustness and performance can be simultaneously assured. Further, the design procedures are summarized as an algorithm to help rapidly locate the GPMSOR and search an optimal PID gain set. Finally, three highly cited examples are provided to illustrate the design process and to demonstrate the effectiveness of the proposed method. PMID:24462232

  4. Marginalization and health geomatics.

    PubMed

    Alexander, Gregory L; Kinman, Edward L; Miller, Louise C; Patrick, Timothy B

    2003-01-01

    Marginalized groups have been defined as groups that have been peripheralized from the center of society. Increasing nursing knowledge of marginalized groups and the dynamics of population diversity will enable nurses to better recognize shifting health patterns, plan for utilization of health services, and determine ethnic and cultural differences that exist in marginalized populations. The authors of this article review theoretical models responsible for defining the concept marginalization, describe geographical information systems as a recommended tool to evaluate marginalized groups, and provide a case study utilizing tools and maps as a means of assessing marginal situations. PMID:14643736

  5. Marginal and happy? The need for uniqueness predicts the adjustment of marginal immigrants.

    PubMed

    Debrosse, Régine; de la Sablonnière, Roxane; Rossignac-Milon, Maya

    2015-12-01

    Marginalization is often presented as the strategy associated with the worst adjustment for immigrants. This study identifies a critical variable that buffers marginal immigrants from the negative effects of marginalization on adjustment: The need for uniqueness. In three studies, we surveyed immigrants recruited on university campuses (n = 119, n = 116) and in the field (n = 61). Among marginal immigrants, a higher need for uniqueness predicted higher self-esteem (Study 1), affect (Study 2), and life satisfaction (Study 3), and marginally higher happiness (Study 2) and self-esteem (Study 3). No relationship between the need for uniqueness and adjustment was found among non-marginal immigrants. The adaptive value of the need for uniqueness for marginal immigrants is discussed. PMID:25903084

  6. Broad Negative Thermal Expansion Operation-Temperature Window Achieved by Adjusting Fe-Fe Magnetic Exchange Coupling in La(Fe,Si)13 Compounds.

    PubMed

    Li, Shaopeng; Huang, Rongjin; Zhao, Yuqiang; Li, Wen; Wang, Wei; Huang, Chuanjun; Gong, Pifu; Lin, Zheshuai; Li, Laifeng

    2015-08-17

    Cubic La(Fe,Si)13-based compounds have been recently developed as promising negative thermal expansion(NTE) materials, but the narrow NTE operation-temperature window(∼110 K) restricts their actual applications. In this work, we demonstrate that the NTE operation-temperature window of LaFe(13-x)Si(x) can be significantly broadened by adjusting Fe-Fe magnetic exchange coupling as x ranges from 2.8 to 3.1. In particular, the NTE operation-temperature window of LaFe10.1Si2.9 is extended to 220 K. More attractively, the coefficients of thermal expansion of LaFe10.0Si3.0 and LaFe9.9Si3.1 are homogeneous in the NTE operation-temperature range of about 200 K, which is much valuable for the stability of fabricating devices. The further experimental characterizations combined with first-principles studies reveal that the tetragonal phase is gradually introduced into the cubic phase as the Si content increases, hence modifies the Fe-Fe interatomic distance. The reduction of the overall Fe-Fe magnetic exchange interactions contributes to the broadness of NTE operation-temperature window for LaFe(13-x)Si(x). PMID:26196377

  7. [Marginalization and health. Introduction].

    PubMed

    Yunes, J

    1992-06-01

    The relationship between marginalization and health is clear. In Mexico, for example, life expectancy is 53 years for the poorest population sectors and 20 years more for the wealthiest. Infant mortality in poor Colombian families is twice that of wealthier families, and one-third of developing countries the rural population is only half as likely as the urban to have access to health services. Women in the Southern hemisphere are 12 times likelier than those in the Northern to die of maternal causes. The most important step in arriving at a solution to the inequity may be to analyze in depth the relationship between marginality and health. Marginality may be defined as the lack of participation of individuals or groups in certain key phases of societal life, such as production, consumption, or political decision making. Marginality came to be viewed as a social problem only with recognition of the rights of all individuals to participate in available social goods. Marginality is always relative, and marginal groups exist because central groups determine the criteria for inclusion in the marginal and central groups. Marginality thus always refers to a concrete society at a specific historical moment. Marginal groups may be of various types. At present, marginal groups include women, rural populations, people with AIDS or mental illness or certain other health conditions, refugees, ethnic or religious groups, homosexuals, and the poor, who are the largest group of marginal persons in the world. Even in developed countries, 100-200 million persons live below the poverty line. Latin America is struggling to emerge from its marginal status in the world. The economic crisis of the 1980s increased poverty in the region, and 40% are not considered impoverished. Latin America is a clear example of the relationship between marginality and health. Its epidemiologic profile is intimately related to nutrition, availability of potable water, housing, and environmental

  8. Mobility and Reading Achievement.

    ERIC Educational Resources Information Center

    Waters, Theresa Z.

    A study examined the effect of geographic mobility on elementary school students' achievement. Although such mobility, which requires students to make multiple moves among schools, can have a negative impact on academic achievement, the hypothesis for the study was that it was not a determining factor in reading achievement test scores. Subjects…

  9. Ocean margins workshop

    SciTech Connect

    1990-12-31

    The Department of Energy (DOE) is announcing the refocusing of its marine research program to emphasize the study of ocean margins and their role in modulating, controlling, and driving Global Change phenomena. This is a proposal to conduct a workshop that will establish priorities and an implementation plan for a new research initiative by the Department of Energy on the ocean margins. The workshop will be attended by about 70 scientists who specialize in ocean margin research. The workshop will be held in the Norfolk, Virginia area in late June 1990.

  10. Organizing marginalized workers.

    PubMed

    Taylor, A K

    1999-01-01

    Figures from the U.S. Department of Labor show that low-wage or marginalized workers are more likely to be injured on the job and suffer more work-related medical conditions than better-paid workers. Despite an increasingly hostile organizing climate, market globalization, and corporate downsizing, significant progress has been made in organizing marginalized workers. A multifaceted, comprehensive organizing strategy, incorporating union-building strategies that include (but are not limited to) safety and health, must be used by unions to successfully organize marginalized workers and obtain the first contract. PMID:10378982

  11. Marginalization of Vocational Psychology.

    ERIC Educational Resources Information Center

    Tinsley, Howard E. A.

    2001-01-01

    Although vocational psychology has diverse theoretical models and an empirical tradition, it is marginalized within counseling psychology. Its vitality is weakened by those who take a dabbler, pundit, or booster approach to scholarship. (Contains 46 references.) (SK)

  12. Marginal energy prices report

    SciTech Connect

    Chaitkin, Stuart; Biermayer, Peter; Bretz, Sarah; Brown, Steve; Constantine, Sachu; Fisher, Diane; Hakim, Sajid; Liew, Lucy; Lutz, Jim; Marnay, Chris; McMahon, James E.; Moezzi, Mithra; Osborn, Julie; Rawner, Esther; Roberson, Judy; Rosenquist, Greg; Ryan, Nancy; Turiel, Isaac; Wiel, Stephen

    1999-06-24

    This report responds to a recommendation from the Department of Energy's (DOE) Advisory Committee on Appliance Energy Efficiency Standards. It presents the derivation of estimated consumer marginal energy prices for the commercial and residential sectors for use in the life-cycle cost (LCC) analyses for four of the high priority appliances' energy efficiency standards rule makings --clothes washers, water heaters,fluorescent lamp ballasts, and central airconditioners/heat pumps. Marginal prices as discussed here are those prices consumers pay (or save) for their last units of energy used (or saved). Marginal prices reflect a change in a consumer's bill (that might be associated with new energy efficiency standards) divided by the corresponding change in the amount of energy the consumer used.

  13. Gigapixel surface imaging of radical prostatectomy specimens for comprehensive detection of cancer-positive surgical margins using structured illumination microscopy

    PubMed Central

    Wang, Mei; Tulman, David B.; Sholl, Andrew B.; Kimbrell, Hillary Z.; Mandava, Sree H.; Elfer, Katherine N.; Luethy, Samuel; Maddox, Michael M.; Lai, Weil; Lee, Benjamin R.; Brown, J. Quincy

    2016-01-01

    Achieving cancer-free surgical margins in oncologic surgery is critical to reduce the need for additional adjuvant treatments and minimize tumor recurrence; however, there is a delicate balance between completeness of tumor removal and preservation of adjacent tissues critical for normal post-operative function. We sought to establish the feasibility of video-rate structured illumination microscopy (VR-SIM) of the intact removed tumor surface as a practical and non-destructive alternative to intra-operative frozen section pathology, using prostate cancer as an initial target. We present the first images of the intact human prostate surface obtained with pathologically-relevant contrast and subcellular detail, obtained in 24 radical prostatectomy specimens immediately after excision. We demonstrate that it is feasible to routinely image the full prostate circumference, generating gigapixel panorama images of the surface that are readily interpreted by pathologists. VR-SIM confirmed detection of positive surgical margins in 3 out of 4 prostates with pathology-confirmed adenocarcinoma at the circumferential surgical margin, and furthermore detected extensive residual cancer at the circumferential margin in a case post-operatively classified by histopathology as having negative surgical margins. Our results suggest that the increased surface coverage of VR-SIM could also provide added value for detection and characterization of positive surgical margins over traditional histopathology. PMID:27257084

  14. Gigapixel surface imaging of radical prostatectomy specimens for comprehensive detection of cancer-positive surgical margins using structured illumination microscopy

    NASA Astrophysics Data System (ADS)

    Wang, Mei; Tulman, David B.; Sholl, Andrew B.; Kimbrell, Hillary Z.; Mandava, Sree H.; Elfer, Katherine N.; Luethy, Samuel; Maddox, Michael M.; Lai, Weil; Lee, Benjamin R.; Brown, J. Quincy

    2016-06-01

    Achieving cancer-free surgical margins in oncologic surgery is critical to reduce the need for additional adjuvant treatments and minimize tumor recurrence; however, there is a delicate balance between completeness of tumor removal and preservation of adjacent tissues critical for normal post-operative function. We sought to establish the feasibility of video-rate structured illumination microscopy (VR-SIM) of the intact removed tumor surface as a practical and non-destructive alternative to intra-operative frozen section pathology, using prostate cancer as an initial target. We present the first images of the intact human prostate surface obtained with pathologically-relevant contrast and subcellular detail, obtained in 24 radical prostatectomy specimens immediately after excision. We demonstrate that it is feasible to routinely image the full prostate circumference, generating gigapixel panorama images of the surface that are readily interpreted by pathologists. VR-SIM confirmed detection of positive surgical margins in 3 out of 4 prostates with pathology-confirmed adenocarcinoma at the circumferential surgical margin, and furthermore detected extensive residual cancer at the circumferential margin in a case post-operatively classified by histopathology as having negative surgical margins. Our results suggest that the increased surface coverage of VR-SIM could also provide added value for detection and characterization of positive surgical margins over traditional histopathology.

  15. Gigapixel surface imaging of radical prostatectomy specimens for comprehensive detection of cancer-positive surgical margins using structured illumination microscopy.

    PubMed

    Wang, Mei; Tulman, David B; Sholl, Andrew B; Kimbrell, Hillary Z; Mandava, Sree H; Elfer, Katherine N; Luethy, Samuel; Maddox, Michael M; Lai, Weil; Lee, Benjamin R; Brown, J Quincy

    2016-01-01

    Achieving cancer-free surgical margins in oncologic surgery is critical to reduce the need for additional adjuvant treatments and minimize tumor recurrence; however, there is a delicate balance between completeness of tumor removal and preservation of adjacent tissues critical for normal post-operative function. We sought to establish the feasibility of video-rate structured illumination microscopy (VR-SIM) of the intact removed tumor surface as a practical and non-destructive alternative to intra-operative frozen section pathology, using prostate cancer as an initial target. We present the first images of the intact human prostate surface obtained with pathologically-relevant contrast and subcellular detail, obtained in 24 radical prostatectomy specimens immediately after excision. We demonstrate that it is feasible to routinely image the full prostate circumference, generating gigapixel panorama images of the surface that are readily interpreted by pathologists. VR-SIM confirmed detection of positive surgical margins in 3 out of 4 prostates with pathology-confirmed adenocarcinoma at the circumferential surgical margin, and furthermore detected extensive residual cancer at the circumferential margin in a case post-operatively classified by histopathology as having negative surgical margins. Our results suggest that the increased surface coverage of VR-SIM could also provide added value for detection and characterization of positive surgical margins over traditional histopathology. PMID:27257084

  16. Negative mass

    NASA Astrophysics Data System (ADS)

    Hammond, Richard T.

    2015-03-01

    Some physical aspects of negative mass are examined. Several unusual properties, such as the ability of negative mass to penetrate any armor, are analysed. Other surprising effects include the bizarre system of negative mass chasing positive mass, naked singularities and the violation of cosmic censorship, wormholes, and quantum mechanical results as well. In addition, a brief look into the implications for strings is given.

  17. Deep continental margin reflectors

    USGS Publications Warehouse

    Ewing, J.; Heirtzler, J.; Purdy, M.; Klitgord, Kim D.

    1985-01-01

    In contrast to the rarity of such observations a decade ago, seismic reflecting and refracting horizons are now being observed to Moho depths under continental shelves in a number of places. These observations provide knowledge of the entire crustal thickness from the shoreline to the oceanic crust on passive margins and supplement Consortium for Continental Reflection Profiling (COCORP)-type measurements on land.

  18. Predicting service life margins

    NASA Technical Reports Server (NTRS)

    Egan, G. F.

    1971-01-01

    Margins are developed for equipment susceptible to malfunction due to excessive time or operation cycles, and for identifying limited life equipment so monitoring and replacing is accomplished before hardware failure. Method applies to hardware where design service is established and where reasonable expected usage prediction is made.

  19. Hourly marginal emissions tool

    EPA Science Inventory

    The hourly marginal emissions tool is an excel workbook that estimates the hourly NOx, SO2 and CO2 emission reductions of energy efficiency and renewable energy policies and programs in the electric power sector. It will be based on EPA's proposed "Road map for Incorporating ene...

  20. Marginalization and School Nursing

    ERIC Educational Resources Information Center

    Smith, Julia Ann

    2004-01-01

    The concept of marginalization was first analyzed by nursing researchers Hall, Stevens, and Meleis. Although nursing literature frequently refers to this concept when addressing "at risk" groups such as the homeless, gays and lesbians, and those infected with HIV/AIDS, the concept can also be applied to nursing. Analysis of current school nursing…

  1. Contribution Margin Budgeting.

    ERIC Educational Resources Information Center

    Tambrino, Paul A.

    2001-01-01

    Describes Iowa Valley Community College District's Contribution Margin Budgeting (CMB) program, successfully implemented to stave off bankruptcy. In this program, each responsibility center receives credit for all income generated and is charged for all expenditures, and each must build its own reserve against revenue shortfalls and unanticipated…

  2. Marginality and Triangle Inequality

    NASA Astrophysics Data System (ADS)

    Nánásiová, O. L̆ga; Valášková, L̆ubica

    2010-12-01

    In this paper we study conditions for the existence of a 3-dimensional s-map on a quantum logic under assumption that marginal s-maps are known. We show that the existence of such a 3-dimensional s-map depends on the triangle inequality of d-map, which on a Boolean algebra represents a measure of symmetric difference.

  3. Volcanic passive margins

    NASA Astrophysics Data System (ADS)

    Geoffroy, Laurent

    2005-12-01

    Compared to non-volcanic ones, volcanic passive margins mark continental break-up over a hotter mantle, probably subject to small-scale convection. They present distinctive genetic and structural features. High-rate extension of the lithosphere is associated with catastrophic mantle melting responsible for the accretion of a thick igneous crust. Distinctive structural features of volcanic margins are syn-magmatic and continentward-dipping crustal faults accommodating the seaward flexure of the igneous crust. Volcanic margins present along-axis a magmatic and tectonic segmentation with wavelength similar to adjacent slow-spreading ridges. Their 3D organisation suggests a connection between loci of mantle melting at depths and zones of strain concentration within the lithosphere. Break-up would start and propagate from localized thermally-softened lithospheric zones. These 'soft points' could be localized over small-scale convection cells found at the bottom of the lithosphere, where adiabatic mantle melting would specifically occur. The particular structure of the brittle crust at volcanic passive margins could be interpreted by active and sudden oceanward flow of both the unstable hot mantle and the ductile part of the lithosphere during the break-up stage. To cite this article: L. Geoffroy, C. R. Geoscience 337 (2005).

  4. The Brazilian continental margin

    NASA Astrophysics Data System (ADS)

    Martins, L. R.; Coutinho, P. N.

    1981-04-01

    The Brazilian continental margin, with its interesting morphology, structure and sediments, has become better known only during the last two decades. Six physiographical provinces can be recognized at the continental margin and the adjacent coast: (1) Cabo Orange-Parnaiba delta; (2) Parnaiba delta-Cabo Sa˜o Roque; (3) Cabo Sa˜o Roque-Belmonte; (4) Belmonte-Cabo Frio; (5) Cabo Frio-Cabo Santa Marta; and (6) Cabo Santa Marta-Chui. The shelf is rather wide near the Amazon Mouth, becoming narrower eastwards, continuing very narrow along the northeastern and eastern coast, and becoming wider again in the south towards the Plate River. Prominent morphological features along the margin are the Amazon cone, the marginal plateaus off northeastern Brazil, the Sa˜o Francisco cone and canyon, the Abrolhos Bank, and the deep-sea plateaus of Pernambuco and Sa˜o Paulo. On the shelf proper a number of relief elements exist, such as sand waves east of the Amazon, submarine terraces at various places, and irregularities of structural origin. The shelf break is rather smooth in the far north and south, more abrupt in the remainder. Surface sediments of the Brazilian shelf show five distinct facies types: littoral quartz sands, mud, transition sand-mud, coralline algae, and biodetrital. The terrigenous elastic fractions dominate off the Amazon and in southern Brazil; between these areas they occupy a very narrow strip near the coast. The carbonate facies, predominantly composed of calcareous algae, is abundant between the Parnaiba delta and Cabo Frio; to the south this facies is more biodetrital and restricted to the outer shelf. Economically important on the Brazilian continental margin besides oil, are sands and gravels, carbonate deposits, evaporites and some subsurface coal. Other possible mineral resources could be phosphate, heavy minerals and clays for ceramics.

  5. Strategies for managing margins.

    PubMed

    2012-08-01

    Potential Medicare and Medicaid reimbursement cuts have made it critical for home health agencies to manage their gross and net operating profit margins. Agencies need to develop tools to analyze their margins and make sure they are following best practices. Try as you may, your agency might still face the question, "Why am I not meeting my budget?" Get some answers in this session from David Berman and Andrea L. Devoti. Berman is a principal at Simione Healthcare Consultants in Hamden, CT, where he is responsible for merchant acquisitions, business valuation due diligence, and oversight of the financial monitor benchmarking tool besides serving as interim chief financial officer. Devoti is chairman of the NAHC board and President & CEO of Neighborhood Health Visiting Nurse Association in West Chester PA. PMID:23074756

  6. Marginal Stability Dynamics for Energetic Particles

    NASA Astrophysics Data System (ADS)

    Berk, Herbert

    2009-11-01

    Marginal stability in plasmas characteristically sets a stiff limit to the range of that can be achieved. Below this limit, the system is governed by classical. Near marginal stability, however, plasmas may be subject to rapid processes, resulting in a system that hovers near marginality. This scenario emerged from nonlinear studies of energetic particle relaxation and may be to more general plasma transport. We describe results from several such which include. [1] Avalanches---Near marginal stability, an important point is whether an instability driven by resonant particles where the distribution function has ``free energy'' will cause global radial diffusion. For that,modes need to overlap. This process can be continuous or bursty, the latter having been recently observed in NSTX and DIII-D. [2] Frequency chirping---Recent simulations by Vann showed that marginal stability can be sustained when there is only one unstable linear mode, due to the mechanism of spontaneous frequency sweeping. Although a single mode near stability should not cause dramatic relaxation, nevertheless in the Vann simulations, the achievement of marginal stability induced a continual chirping of that had removed energy from the bulk of the region where the external beam to deposit free energy. The distribution was then found to hover near stability. This mechanism may apply to the n=0 GAM where frequency sweeping might be a mechanism for extracting energy from alpha particles in a burning plasma, thereby reducing the stored alpha particle pressure. One way to implement this is to have the n=0 geodesic acoustic modes (GAM) be preferentially excited, since energy rather than momentum (leading to spatial diffusion) is then primarily extracted from alpha particles.

  7. Factors affecting surgical margin recurrence after hepatectomy for colorectal liver metastases

    PubMed Central

    Akyuz, Muhammet; Aucejo, Federico; Quintini, Cristiano; Miller, Charles; Fung, John

    2016-01-01

    Background Hepatic recurrence after resection of colorectal liver metastasis (CLM) occurs in 50% of patients during follow-up, with 2.8% to 13.9% presenting with surgical margin recurrence (SMR). The aim of this study is to analyze factors that related to SMR in patients with CLM undergoing hepatectomy. Methods Demographics, clinical and survival data of patients who underwent hepatectomy were identified from a prospectively maintained, institutional review board (IRB)-approved database between 2000 and 2012. Statistical analysis was performed using univariate Kaplan Meier and Cox proportional hazard model. Results There were 85 female and 121 male patients who underwent liver resection for CLM. An R0 resection was performed in 157 (76%) patients and R1 resection in 49. SMR was detected in 32 patients (15.5%) followed up for a median of 29 months (range, 3–121 months). A half of these patients had undergone R1 (n=16) and another half R0 resection (n=16). Tumor size, preoperative carcinoembryonic antigen (CEA) level and margin status were associated with SMR on univariate analysis. On multivariate analysis, a positive surgical margin was the only independent predictor of SMR. The receipt of adjuvant chemotherapy did not affect margin recurrence. SMR was an independent risk factor associated with worse disease-free (DFS) and overall survival (OS). Conclusions This study shows that SMR, which can be detected in up to 15.5% of patients after liver resection for CLM, adversely affects DFS and OS. The fact that a positive surgical margin was the only predictive factor for SMR in these patients underscores the importance of achieving negative margins during hepatectomy. PMID:27294032

  8. Abrupt plate accelerations shape rifted continental margins.

    PubMed

    Brune, Sascha; Williams, Simon E; Butterworth, Nathaniel P; Müller, R Dietmar

    2016-08-11

    Rifted margins are formed by persistent stretching of continental lithosphere until breakup is achieved. It is well known that strain-rate-dependent processes control rift evolution, yet quantified extension histories of Earth's major passive margins have become available only recently. Here we investigate rift kinematics globally by applying a new geotectonic analysis technique to revised global plate reconstructions. We find that rifted margins feature an initial, slow rift phase (less than ten millimetres per year, full rate) and that an abrupt increase of plate divergence introduces a fast rift phase. Plate acceleration takes place before continental rupture and considerable margin area is created during each phase. We reproduce the rapid transition from slow to fast extension using analytical and numerical modelling with constant force boundary conditions. The extension models suggest that the two-phase velocity behaviour is caused by a rift-intrinsic strength--velocity feedback, which can be robustly inferred for diverse lithosphere configurations and rheologies. Our results explain differences between proximal and distal margin areas and demonstrate that abrupt plate acceleration during continental rifting is controlled by the nonlinear decay of the resistive rift strength force. This mechanism provides an explanation for several previously unexplained rapid absolute plate motion changes, offering new insights into the balance of plate driving forces through time. PMID:27437571

  9. East Africa continental margins

    SciTech Connect

    Bosellini, A.

    1986-01-01

    New well data from Somalia, together with the history of sea-floor spreading in the Indian Ocean derived from magnetic anomalies, show that the East African margins from latitude 15/sup 0/S into the Gulf of Aden comprise four distinct segments that formed successively by the southward drift of Madagascar from Somalia during the Middle to Late Jurassic and Early Cretaceous, by the northeastward drift of India along the Owen Transform during the Late Cretaceous and Paleocene, and by the opening of the Gulf of Aden during the Neogene.

  10. Amphetamine margin in sports

    SciTech Connect

    Laties, V.G.; Weiss, B.

    1981-10-01

    The amphetamines can enhance athletic performance. That much seem clear from the literature, some of which is reviewed here. Increases in endurance have been demonstrated in both humans and rats. Smith and Beecher, 20 years ago, showed improvement of running, swimming, and weight throwing in highly trained athletes. Laboratory analogs of such performances have also been used and similar enhancement demonstrated. The amount of change induced by the amphetamines is usually small, of the order of a few percent. Nevertheless, since a fraction of a percent improvement can make the difference between fame and oblivion, the margin conferred by these drugs can be quite important.

  11. Structural Margins Assessment Approach

    NASA Technical Reports Server (NTRS)

    Ryan, Robert S.

    1988-01-01

    A general approach to the structural design and verification used to determine the structural margins of the space vehicle elements under Marshall Space Flight Center (MSFC) management is described. The Space Shuttle results and organization will be used as illustrations for techniques discussed. Given also are: (1) the system analyses performed or to be performed by, and (2) element analyses performed by MSFC and its contractors. Analysis approaches and their verification will be addressed. The Shuttle procedures are general in nature and apply to other than Shuttle space vehicles.

  12. Perceived social loafing and anticipated effort reduction among young football (soccer) players: an achievement goal perspective.

    PubMed

    Høigaard, Rune; Ommundsen, Yngvar

    2007-06-01

    This study investigated the relationship between motivational climates, personal achievement goals, and three different aspects of social loafing in football (soccer). 170 male competitive football players completed questionnaires assessing perceived motivational climate, achievement goal, and measures of perceived social loafing (anticipation of lower effort amongst their teammates and themselves). The results indicated a marginal but significant positive relationship between an ego-oriented achievement goal and perceived social loafing. In addition, a mastery climate was negatively associated with perceived social loafing and anticipation of lower effort of team members, particularly for athletes who also strongly endorsed a task-oriented achievement goal. A performance climate, in contrast, related positively with these two aspects of social loafing. A mastery climate also related negatively to the third aspect of social loafing, i.e., players' readiness to reduce their own effort in response to their perception of social loafing among their teammates. PMID:17688105

  13. Soft tissue sarcomas of the distal lower extremities: A single-institutional analysis of the prognostic significance of surgical margins in 120 patients.

    PubMed

    Harati, Kamran; Kirchhoff, Pascal; Behr, Björn; Daigeler, Adrien; Goertz, Ole; Hirsch, Tobias; Lehnhardt, Marcus; Ring, Andrej

    2016-08-01

    Soft tissue sarcomas (STS) arising in the distal lower extremities pose a therapeutic challenge due to concerns of functional morbidity. The impact of surgical margins on local recurrence‑free survival (LRFS) and overall survival (OS) still remains controversial. The aim of this study was to identify prognostic indicators of survival and functional outcome in patients with STS of the distal lower extremities through a long‑term follow‑up. Between 1999 and 2014, 120 patients with STS of the foot, ankle and lower leg were treated surgically at our institution. The median follow‑up was 6.3 years. The results reveal that the 5‑year estimate of the OS rate was 80.0% [95% confidence interval (CI): 69.6‑87.1] for the entire series. Surgical margins attained at the resection of the primary tumor did not influence OS significantly [5‑year OS: R0 80.5% (69.7‑87.9) vs. R1 74.1% (28.9‑93.0); P=0.318]. Within the R0 subgroup, negative surgical margin widths ≤1 and >1 mm led to similar outcomes, as well as ≤5 and >5 mm, respectively. In the multivariate analysis, significant adverse prognostic features included male gender and age >60 years at the time point of primary diagnosis. In conclusion, the data from this study could not underscore the long‑term benefit of negative margins achieved at the resection of the primary tumor. Surgical efforts should aim at function‑sparing resections when feasible with negative margins. Here, close negative margins seem to be adequate. PMID:27278861

  14. Marginally Stable Nuclear Burning

    NASA Technical Reports Server (NTRS)

    Strohmayer, Tod E.; Altamirano, D.

    2012-01-01

    Thermonuclear X-ray bursts result from unstable nuclear burning of the material accreted on neutron stars in some low mass X-ray binaries (LMXBs). Theory predicts that close to the boundary of stability oscillatory burning can occur. This marginally stable regime has so far been identified in only a small number of sources. We present Rossi X-ray Timing Explorer (RXTE) observations of the bursting, high- inclination LMXB 4U 1323-619 that reveal for the first time in this source the signature of marginally stable burning. The source was observed during two successive RXTE orbits for approximately 5 ksec beginning at 10:14:01 UTC on March 28, 2011. Significant mHz quasi- periodic oscillations (QPO) at a frequency of 8.1 mHz are detected for approximately 1600 s from the beginning of the observation until the occurrence of a thermonuclear X-ray burst at 10:42:22 UTC. The mHz oscillations are not detected following the X-ray burst. The average fractional rms amplitude of the mHz QPOs is 6.4% (3 - 20 keV), and the amplitude increases to about 8% below 10 keV.This phenomenology is strikingly similar to that seen in the LMXB 4U 1636-53. Indeed, the frequency of the mHz QPOs in 4U 1323-619 prior to the X-ray burst is very similar to the transition frequency between mHz QPO and bursts found in 4U 1636-53 by Altamirano et al. (2008). These results strongly suggest that the observed QPOs in 4U 1323-619 are, like those in 4U 1636-53, due to marginally stable nuclear burning. We also explore the dependence of the energy spectrum on the oscillation phase, and we place the present observations within the context of the spectral evolution of the accretion-powered flux from the source.

  15. Marginalization in neural circuits with divisive normalization

    PubMed Central

    Beck, J.M.; Latham, P.E.; Pouget, A.

    2011-01-01

    A wide range of computations performed by the nervous system involves a type of probabilistic inference known as marginalization. This computation comes up in seemingly unrelated tasks, including causal reasoning, odor recognition, motor control, visual tracking, coordinate transformations, visual search, decision making, and object recognition, to name just a few. The question we address here is: how could neural circuits implement such marginalizations? We show that when spike trains exhibit a particular type of statistics – associated with constant Fano factors and gain-invariant tuning curves, as is often reported in vivo – some of the more common marginalizations can be achieved with networks that implement a quadratic nonlinearity and divisive normalization, the latter being a type of nonlinear lateral inhibition that has been widely reported in neural circuits. Previous studies have implicated divisive normalization in contrast gain control and attentional modulation. Our results raise the possibility that it is involved in yet another, highly critical, computation: near optimal marginalization in a remarkably wide range of tasks. PMID:22031877

  16. Frozen Section Interpretation of Pancreatic Margins: Subspecialized Gastrointestinal Pathologists Versus General Pathologists.

    PubMed

    Liu, Yong-Jun; Smith-Chakmakova, Faye; Rassaei, Negar; Han, Bing; Enomoto, Laura M; Crist, Henry; Hollenbeak, Christopher S; Karamchandani, Dipti M

    2016-04-01

    Intraoperative assessment of pancreatic parenchymal margin during pancreatectomies is challenging and misinterpretation by the pathologist is a cause of incorrect frozen section (FS) diagnosis. Although the current literature supports that pancreatic margin FS diagnosis and its accuracy has no impact on the patient outcome for pancreatic ductal adenocarcinoma (PDAC) patients and reexcision in an attempt to achieve a negative intraoperative pancreatic margin after positive FS is not associated with increased overall survival; still it remains a routine practice in many institutions. To this end, we sought to assess the interobserver variation and accuracy of FS diagnosis between subspecialized gastrointestinal/pancreatobiliary (GI) and general pathologists. Seventy seven consecutive pancreatic parenchymal margin FSs performed on pancreatectomies for PDAC from 2010 to 2013 were retrieved at our institution. These were retrospectively evaluated by 2 GI and 2 general pathologists independently without knowledge of the original FS diagnosis or the final diagnosis. The specificity, sensitivity, positive predictive value, negative predictive value, and accuracy of GI versus general pathologist was 97.8% versus 87.5%, 61.1% versus 66.7%, 78.6% versus 41.4%, 95% versus 95.2%, and 93.5% versus 85.1%, respectively. The interobserver agreement between GI and general pathologists was fair (κ = .337, P < .001). The interobserver agreement between 2 GI pathologists was fair (κ = .373, P = .0005) and between 2 general pathologists was slight (κ = .195, P = .042). Although overall accuracy of subspecialized GI pathologists was higher than that of general pathologists, none had an accuracy of 100%. Our study reaffirms the challenging nature of these FSs. PMID:26378055

  17. Positive margins prediction in breast cancer conservative surgery: Assessment of a preoperative web-based nomogram.

    PubMed

    Alves-Ribeiro, Lídia; Osório, Fernando; Amendoeira, Isabel; Fougo, José Luís

    2016-08-01

    Margin status of the surgical specimen has been shown to be a prognostic and risk factor for local recurrence in breast cancer surgery. It has been studied as a topic of intervention to diminish reoperation rates and reduce the probability of local recurrence in breast conservative surgery (BCS). This study aims to validate the Dutch BreastConservation! nomogram, created by Pleijhus et al., which predicts preoperative probability of positive margins in BCS. Patients with diagnosis of breast cancer stages cT1-2, who underwent BCS at the Breast Center of São João University Hospital (BC-CHSJ) in 2013-2014, were included. Association and correlation were evaluated for clinical, radiological, pathological and surgical variables. Multivariable logistic regression and ROC curves were used to assess nomogram parameters and discrimination. In our series of 253 patients, no associations were found between margin status and other studied variables (such as age or family history of breast cancer), except for weight (p-value = 0.045) and volume (p-value = 0.012) of the surgical specimen. Regarding the nomogram, a statistically significant association was shown between cN1 status and positive margins (p-value = 0.014). No differences were registered between the scores of patients with positive versus negative margins. Discrimination analysis showed an AUC of 0.474 for the basic and 0.508 for the expanded models. We cannot assume its external validation or its applicability to our cohort. Further studies are needed to determine the validity of this nomogram and achieve a broader view of currently available tools. PMID:27326978

  18. Ivory Coast-Ghana margin: model of a transform margin

    SciTech Connect

    Mascle, J.; Blarez, E.

    1987-05-01

    The authors present a marine study of the eastern Ivory Coast-Ghana continental margins which they consider one of the most spectacular extinct transform margins. This margin has been created during Early-Lower Cretaceous time and has not been submitted to any major geodynamic reactivation since its fabric. Based on this example, they propose to consider during the evolution of the transform margin four main and successive stages. Shearing contact is first active between two probably thick continental crusts and then between progressively thinning continental crusts. This leads to the creation of specific geological structures such as pull-apart graben, elongated fault lineaments, major fault scarps, shear folds, and marginal ridges. After the final continental breakup, a hot center (the mid-oceanic ridge axis) is progressively drifting along the newly created margin. The contact between two lithospheres of different nature should necessarily induce, by thermal exchanges, vertical crustal readjustments. Finally, the transform margin remains directly adjacent to a hot but cooling oceanic lithosphere; its subsidence behavior should then progressively be comparable to the thermal subsidence of classic rifted margins.

  19. The marginalization of hormesis.

    PubMed

    Calabrese, E J; Baldwin, L A

    2000-01-01

    Despite the substantial development and publication of highly reproducible toxicological data, the concept of hormetic dose-response relationships was never integrated into the mainstream of toxicological thought. Review of the historical foundations of the interpretation of the bioassay and assessment of competitive theories of dose-response relationships lead to the conclusion that multiple factors contributed to the marginalization of hormesis during the middle and subsequent decades of the 20th century. These factors include: (a) the close-association of hormesis with homeopathy lead to the hostility of modern medicine toward homeopathy thereby creating a guilt by association framework, and the carry-over influence of that hostility in the judgements of medically-based pharmacologists/ toxicologists toward hormesis; (b) the emphasis of high dose effects linked with a lack of appreciation of the significance of the implications of low dose stimulatory effects; (c) the lack of an evolutionary-based mechanism(s) to account for hormetic effects; and (d) the lack of appropriate scientific advocates to counter aggressive and intellectually powerful critics of the hormetic perspective. PMID:10745293

  20. The marginalization of hormesis.

    PubMed

    Calabrese, E J; Baldwin, L A

    1999-01-01

    Despite the substantial development and publication of highly reproducible toxicological data, the concept of hormetic dose-response relationships was never integrated into the mainstream of toxicological thought. Review of the historical foundations of the interpretation of the bioassay and assessment of competitive theories of dose-response relationships lead to the conclusion that multiple factors contributed to the marginalization of hormesis during the middle and subsequent decades of the 20th Century. These factors include the following: (a) the close association of hormesis with homeopathy, which led to the hostility of modern medicine toward homeopathy, thereby creating a guilt-by-association framework, and the carryover influence of that hostility toward hormesis in the judgements of medically based pharmacologists/toxicologists; (b) the emphasis of high-dose effects linked with a lack of appreciation of the significance of the implications of low-dose stimulatory effects; (c) the lack of an evolution-based mechanism(s) to account for hormetic effects; and (d) lack of appropriate scientific advocates to counter aggressive and intellectually powerful critics of the hormetic perspective. PMID:10207983

  1. Pre-transplant achievement of negativity in minimal residual disease and French-American-British L1 morphology predict superior outcome after allogeneic transplant for Philadelphia chromosome positive acute lymphoblastic leukemia: an analysis of Southeast Asian patients.

    PubMed

    Ma, Liyuan; Hao, Siguo; Diong, Colin; Goh, Yeow-Tee; Gopalakrishnan, Sathish; Ho, Aloysius; Hwang, William; Koh, Liang-Piu; Koh, Mickey; Lim, Zi-Yi; Loh, Yvonne; Poon, Michelle; Tan, Lip-Kun; Tan, Patrick; Linn, Yeh-Ching

    2015-05-01

    To better understand predictive factors and improve the clinical outcome of allogeneic transplant for patients with Philadelphia positive acute lymphoblastic leukemia, we analyzed 67 Southeast Asian patients transplanted in our institutions. Multivariate analysis showed that disease status before transplant, year of transplant and, interestingly, French-American-British (FAB) subtype had a significant impact on overall survival (OS) and non-relapse mortality. Patients who were minimal residual disease (MRD) negative at transplant had a 3-year OS of 73% compared to those who were MRD positive (45%) and refractory (0%). The 3-year cumulative incidence of relapse was 18% and 36% for the MRD negative and positive groups, respectively. FAB L1 subtype had a significantly superior 3-year OS of 63% vs. 29% for L2 subtype. Pre-transplant use of a tyrosine kinase inhibitor significantly improved outcomes in univariate but not multivariate analysis, as it served to induce more patients into MRD negativity, which was the factor that directly improved transplant outcome. PMID:25139689

  2. Acidalia Planitia Channel Margin

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    The THEMIS VIS camera is capable of capturing color images of the Martian surface using five different color filters. In this mode of operation, the spatial resolution and coverage of the image must be reduced to accommodate the additional data volume produced from using multiple filters. To make a color image, three of the five filter images (each in grayscale) are selected. Each is contrast enhanced and then converted to a red, green, or blue intensity image. These three images are then combined to produce a full color, single image. Because the THEMIS color filters don't span the full range of colors seen by the human eye, a color THEMIS image does not represent true color. Also, because each single-filter image is contrast enhanced before inclusion in the three-color image, the apparent color variation of the scene is exaggerated. Nevertheless, the color variation that does appear is representative of some change in color, however subtle, in the actual scene. Note that the long edges of THEMIS color images typically contain color artifacts that do not represent surface variation.

    This false color image shows craters and a channel margin, in the region of southern Acidalia Planitia where Tiu and Ares Valles empty into the planitia. This image was collected during the Northern Spring season.

    Image information: VIS instrument. Latitude 23.8, Longitude 327.5 East (32.5 West). 37 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion

  3. A quantitative microscopic approach to predict local recurrence based on in vivo intraoperative imaging of sarcoma tumor margins.

    PubMed

    Mueller, Jenna L; Fu, Henry L; Mito, Jeffrey K; Whitley, Melodi J; Chitalia, Rhea; Erkanli, Alaattin; Dodd, Leslie; Cardona, Diana M; Geradts, Joseph; Willett, Rebecca M; Kirsch, David G; Ramanujam, Nimmi

    2015-11-15

    The goal of resection of soft tissue sarcomas located in the extremity is to preserve limb function while completely excising the tumor with a margin of normal tissue. With surgery alone, one-third of patients with soft tissue sarcoma of the extremity will have local recurrence due to microscopic residual disease in the tumor bed. Currently, a limited number of intraoperative pathology-based techniques are used to assess margin status; however, few have been widely adopted due to sampling error and time constraints. To aid in intraoperative diagnosis, we developed a quantitative optical microscopy toolbox, which includes acriflavine staining, fluorescence microscopy, and analytic techniques called sparse component analysis and circle transform to yield quantitative diagnosis of tumor margins. A series of variables were quantified from images of resected primary sarcomas and used to optimize a multivariate model. The sensitivity and specificity for differentiating positive from negative ex vivo resected tumor margins was 82 and 75%. The utility of this approach was tested by imaging the in vivo tumor cavities from 34 mice after resection of a sarcoma with local recurrence as a bench mark. When applied prospectively to images from the tumor cavity, the sensitivity and specificity for differentiating local recurrence was 78 and 82%. For comparison, if pathology was used to predict local recurrence in this data set, it would achieve a sensitivity of 29% and a specificity of 71%. These results indicate a robust approach for detecting microscopic residual disease, which is an effective predictor of local recurrence. PMID:25994353

  4. Creating Community on the Margins: The Successful Black Female Academician

    ERIC Educational Resources Information Center

    Hinton, Dawn

    2010-01-01

    The experiences of a Black Female academic, working at a Predominately White Institution (PWI), is explored in this work. The author suggests that Black women have been historically marginalized within most PWI's and historically this has been viewed in a negative light. Here it is suggested that Black women in academe view this position as one of…

  5. Divergent/passive margin basins

    SciTech Connect

    Edwards, J.D. ); Santogrossi, P.A. )

    1989-01-01

    This book discusses the detailed geology of the four divergent margin basins and establishes a set of analog scenarios which can be used for future petroleum exploration. The divergent margin basins are the Campos basin of Brazil, the Gabon basin, the Niger delta, and the basins of the northwest shelf of Australia. These four petroleum basins present a wide range of stratigraphic sequences and structural styles that represent the diverse evolution of this large and important class of world petroleum basins.

  6. Steel Industry Marginal Opportunity Analysis

    SciTech Connect

    none,

    2005-09-01

    The Steel Industry Marginal Opportunity Analysis (PDF 347 KB) identifies opportunities for developing advanced technologies and estimates both the necessary funding and the potential payoff. This analysis determines what portion of the energy bandwidth can be captured through the adoption of state-of-the-art technology and practices. R&D opportunities for addressing the remainder of the bandwidth are characterized and plotted on a marginal opportunity curve.

  7. Evaluation of surgical margins in anatomic pathology: technical, conceptual, and clinical considerations.

    PubMed

    Wick, Mark R; Mills, Stacey E

    2002-11-01

    Virtually all anatomic pathologists are involved in the assessment of tissue margins in surgical procedures that are performed for malignant diseases. The natural tendency to view this process as uncomplicated has, in recent years, been countered by a body of literature on the biological milieu of the marginal zone. Moreover, empirical clinical information has shown that "negative" and "positive" marginal status has an imperfect correlation with risk of recurrent disease in several organ systems and in reference to various tumor types. Problems also remain regarding the optimal techniques for pathologic sampling of margins; the possible roles, if any, of adjuvant (eg, immunohistologic and "molecular") procedures for margin evaluation, and reporting motifs for selected surgical resections. This review considers conceptual data now available on surgical margins, provides a working approach to the generic assessment of marginal surfaces, and presents organ- and tumor- specific information pertaining to this area of practice. PMID:12469788

  8. [In vitro comparison of marginal adaptation of various filling materials. I. Effect of the filling material on marginal adaptation].

    PubMed

    Kóhalmi, T; Gorzo, I; Mari, A; Nagy, K

    1999-03-01

    In a two-month in vitro experiment cervical marginal adaptation was examined in relation to the preparation, filling method and restorative material. Fifty Class II cavities were prepared in fifty extracted sound human premolar and molar teeth extending to the approximal cement-enamel junction. The cavities to receive composite restorations were bevelled at the vestibulo-occlusal and -approximal enamel margins, the other aspects of the cavity enamel and gingival margins at the cement-enamel junction being prepared conventionally. The cavities for amalgam were prepared and filled conventionally. The specimens were cycled in different buffer solutions and temperature, modelling possible variations in the oral environment and examined with SEM. The results were analysed using ANOVA. The best marginal adaptation among the composites was achieved with Charisma, Estilux Posterior, Durafil and Prisma AP. H at the bevelled enamel margins, the worst marginal fit was with Heliomolar and Polofil. It was concluded, that adhesive technique reduces, but does not eliminate marginal leakage. PMID:10205985

  9. Margins in breast conserving surgery: A practice-changing process.

    PubMed

    Rubio, I T; Ahmed, M; Kovacs, T; Marco, V

    2016-05-01

    Margins in breast conserving surgery (BCS) have been a long standing subject debate. This largely arises from the absence of a consensus on what constitutes an adequate margin width, resulting in re-excision rates of 25-40% for close or positive margins and its consequent impact upon cosmesis, economic costs, patient dissatisfaction and lack of bearing on survival. Accepting that the increased risk of local recurrences (LR) has its influence on survival, the decrease in LR in BCS in the last decade have been motivated by better surgical techniques for assessing negative margins, use of targeted therapies and in general with the multimodal treatment in the management of breast cancer patients. Since the publication of the consensus guidelines on margins there has evolved a trend of changing attitudes towards re-excision. Surgeons are considering margins in the context of all factors including not only patient and tumor characteristics but also the regional and systemic treatment the patient is receiving. PMID:26880017

  10. Future consequences of decreasing marginal production efficiency in the high-yielding dairy cow.

    PubMed

    Moallem, U

    2016-04-01

    The objectives were to examine the gross and marginal production efficiencies in high-yielding dairy cows and the future consequences on dairy industry profitability. Data from 2 experiments were used in across-treatments analysis (n=82 mid-lactation multiparous Israeli-Holstein dairy cows). Milk yields, body weights (BW), and dry matter intakes (DMI) were recorded daily. In both experiments, cows were fed a diet containing 16.5 to 16.6% crude protein and net energy for lactation (NEL) at 1.61 Mcal/kg of dry matter (DM). The means of milk yield, BW, DMI, NEL intake, and energy required for maintenance were calculated individually over the whole study, and used to calculate gross and marginal efficiencies. Data were analyzed in 2 ways: (1) simple correlation between variables; and (2) cows were divided into 3 subgroups, designated low, moderate, and high DMI (LDMI, MDMI, and HDMI), according to actual DMI per day: ≤ 26 kg (n=27); >26 through 28.2 kg (n=28); and >28.2 kg (n=27). The phenotypic Pearson correlations among variables were analyzed, and the GLM procedure was used to test differences between subgroups. The relationships between milk and fat-corrected milk yields and the corresponding gross efficiencies were positive, whereas BW and gross production efficiency were negatively correlated. The marginal production efficiency from DM and energy consumed decreased with increasing DMI. The difference between BW gain as predicted by the National Research Council model (2001) and the present measurements increased with increasing DMI (r=0.68). The average calculated energy balances were 1.38, 2.28, and 4.20 Mcal/d (standard error of the mean=0.64) in the LDMI, MDMI, and HDMI groups, respectively. The marginal efficiency for milk yields from DMI or energy consumed was highest in LDMI, intermediate in MDMI, and lowest in HDMI. The predicted BW gains for the whole study period were 22.9, 37.9, and 75.8 kg for the LDMI, MDMI, and HDMI groups, respectively. The

  11. Atlantic marginal basins of Africa

    SciTech Connect

    Moore, G.T.

    1988-02-01

    The over 10,000-km long Atlantic margin of Africa is divisible into thirty basins or segments of the margin that collectively contain over 18.6 x 10/sup 6/ km/sup 3/ of syn-breakup and post-breakup sediments. Twenty of these basins contain a sufficiently thick volume of sediments to be considered prospects. These basins lie, at least partially, within the 200 m isobath. The distribution of source rocks is broad enough to give potential to each of these basins. The sedimentation patterns, tectonics, and timing of events differ from basin to basin and are related directly to the margin's complex history. Two spreading modes exist: rift and transform. Rifting dates from Late Triassic-Early Jurassic in the northwest to Early Cretaceous south of the Niger Delta. A complex transform fault system separated these two margins. Deep-water communication between the two basins became established in the middle Cretaceous. This Mesozoic-Cenozoic cycle of rifting and seafloor spreading has segmented the margin and where observable, basins tend to be bounded by these segments.

  12. The northern Egyptian continental margin

    NASA Astrophysics Data System (ADS)

    Badawy, Ahmed; Mohamed, Gad; Omar, Khaled; Farid, Walid

    2015-01-01

    Africa displays a variety of continental margin structures, tectonics and sedimentary records. The northern Egyptian continental margin represents the NE portion of the North African passive continental margin. Economically, this region is of great importance as a very rich and productive hydrocarbon zone in Egypt. Moreover, it is characterized by remarkable tectonic setting accompanied by active tectonic processes from the old Tethys to recent Mediterranean. In this article, seismicity of the northern Egyptian continental margin has been re-evaluated for more than 100-years and the source parameters of three recent earthquakes (October 2012, January 2013 and July 2013) have been estimated. Moment tensor inversions of 19th October 2012 and 17th January 2013 earthquakes reveal normal faulting mechanism with strike-slip component having seismic moment of 3.5E16 N m and 4.3E15 N m respectively. The operation of the Egyptian National Seismic Network (ENSN) since the end of 1997 has significantly enhanced the old picture of earthquake activity across northern Egyptian continental margin whereas; the record-ability (annual rate) has changed from 2-events/year to 54-event/year before and after ENSN respectively. The spatial distribution of earthquakes foci indicated that the activity tends to cluster at three zones: Mediterranean Ridge (MR), Nile Cone (NC) and Eratosthenes Seamount (ERS). However, two seismic gaps are reported along Levant Basin (LEV) and Herodotus Basin (HER).

  13. Certifying nonlocality from separable marginals

    NASA Astrophysics Data System (ADS)

    Vértesi, Tamás; Laskowski, Wiesław; Pál, Károly F.

    2014-01-01

    Imagine three parties, Alice, Bob, and Charlie, who share a state of three qubits such that all two-party reduced states A-B, A-C, and B-C are separable. Suppose that they have information only about these marginals but not about the global state. According to recent results, there exists an example for a set of three separable two-party reduced states that is only compatible with an entangled global state. In this paper, we show a stronger result by exhibiting separable two-party reduced states A-B, A-C, and B-C, such that any global state compatible with these marginals is nonlocal. Hence, we obtain that nonlocality of multipartite states can be certified from information only about separable marginals.

  14. Dream Catchers: "Margin Call," "Boss," and Climbing the Beanstalk

    ERIC Educational Resources Information Center

    Beck, Bernard

    2012-01-01

    Two recent popular entertainments, "Margin Call" (Barnum, Dodson, Jenckes, Moosa, Quinto & Chandor, 2011) and "Boss" (Safinia, 2011), depict powerful and successful groups of bosses confronting sudden, extreme threats. They are forced to react quickly and sacrifice important values to achieve survival of their organizations. In these emergencies,…

  15. Southern African continental margin: Dynamic processes of a transform margin

    NASA Astrophysics Data System (ADS)

    Parsiegla, N.; Stankiewicz, J.; Gohl, K.; Ryberg, T.; Uenzelmann-Neben, G.

    2009-03-01

    Dynamic processes at sheared margins associated with the formation of sedimentary basins and marginal ridges are poorly understood. The southern African margin provides an excellent opportunity to investigate the deep crustal structure of a transform margin and to characterize processes acting at these margins by studying the Agulhas-Falkland Fracture Zone, the Outeniqua Basin, and the Diaz Marginal Ridge. To do this, we present the results of the combined seismic land-sea experiments of the Agulhas-Karoo Geoscience Transect. Detailed velocity-depth models show crustal thicknesses varying from ˜42 km beneath the Cape Fold Belt to ˜28 km beneath the shelf. The Agulhas-Falkland Fracture Zone is embedded in a 50 km wide transitional zone between continental and oceanic crust. The oceanic crust farther south exhibits relatively low average crustal velocities (˜6.0 km/s), which can possibly be attributed to transform-ridge intersection processes and the thermal effects of the adjacent continental crust during its formation. Crustal stretching factors derived from the velocity-depth models imply that extension in the Outeniqua Basin acted on regional as well as more local scales. We highlight evidence for two episodes of crustal stretching. The first, with a stretching factor β of 1.6, is interpreted to have influenced the entire Outeniqua Basin. The stresses possibly originated from the beginning breakup between Africa and Antarctica (˜169-155 Ma). The second episode can be associated with a transtensional component of the shear motion along the Agulhas-Falkland Transform from ˜136 Ma. This episode caused additional crustal stretching with β = 1.3 and is established to only have affected the southern parts of the basin. Crustal velocities directly beneath the Outeniqua Basin are consistent with the interpretation of Cape Supergroup rocks underlying most parts of the basin and the Diaz Marginal Ridge. We propose that the formation of this ridge can be either

  16. 17 CFR 41.45 - Required margin.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 17 Commodity and Securities Exchanges 1 2011-04-01 2011-04-01 false Required margin. 41.45 Section... PRODUCTS Customer Accounts and Margin Requirements § 41.45 Required margin. (a) Applicability. Each security futures intermediary shall determine the required margin for the security futures and...

  17. 17 CFR 41.45 - Required margin.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Required margin. 41.45 Section... PRODUCTS Customer Accounts and Margin Requirements § 41.45 Required margin. (a) Applicability. Each security futures intermediary shall determine the required margin for the security futures and...

  18. 17 CFR 242.403 - Required margin.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 17 Commodity and Securities Exchanges 3 2011-04-01 2011-04-01 false Required margin. 242.403...) REGULATIONS M, SHO, ATS, AC, AND NMS AND CUSTOMER MARGIN REQUIREMENTS FOR SECURITY FUTURES Customer Margin Requirements for Security Futures § 242.403 Required margin. (a) Applicability. Each security...

  19. 12 CFR 220.4 - Margin account.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 3 2011-01-01 2011-01-01 false Margin account. 220.4 Section 220.4 Banks and... BROKERS AND DEALERS (REGULATION T) § 220.4 Margin account. (a) Margin transactions. (1) All transactions not specifically authorized for inclusion in another account shall be recorded in the margin...

  20. Extensive management of field margins enhances their potential for off-site soil erosion mitigation.

    PubMed

    Ali, Hamada E; Reineking, Björn

    2016-03-15

    Soil erosion is a widespread problem in agricultural landscapes, particularly in regions with strong rainfall events. Vegetated field margins can mitigate negative impacts of soil erosion off-site by trapping eroded material. Here we analyse how local management affects the trapping capacity of field margins in a monsoon region of South Korea, contrasting intensively and extensively managed field margins on both steep and shallow slopes. Prior to the beginning of monsoon season, we equipped a total of 12 sites representing three replicates for each of four different types of field margins ("intensive managed flat", "intensive managed steep", "extensive managed flat" and "extensive managed steep") with Astroturf mats. The mats (n = 15/site) were placed before, within and after the field margin. Sediment was collected after each rain event until the end of the monsoon season. The effect of management and slope on sediment trapping was analysed using linear mixed effects models, using as response variable either the sediment collected within the field margin or the difference in sediment collected after and before the field margin. There was no difference in the amount of sediment reaching the different field margin types. In contrast, extensively managed field margins showed a large reduction in collected sediment before and after the field margins. This effect was pronounced in steep field margins, and increased with the size of rainfall events. We conclude that a field margin management promoting a dense vegetation cover is a key to mitigating negative off-site effects of soil erosion in monsoon regions, particularly in field margins with steep slopes. PMID:26760443

  1. Influence of intrafraction motion on margins for prostate radiotherapy

    SciTech Connect

    Litzenberg, Dale W. . E-mail: litzen@umich.edu; Balter, James M.; Hadley, Scott W.; Sandler, Howard M.; Willoughby, Twyla R.; Kupelian, Patrick A.; Levine, Lisa

    2006-06-01

    Purpose: To assess the impact of intrafraction intervention on margins for prostate radiotherapy. Methods and Materials: Eleven supine prostate patients with three implanted transponders were studied. The relative transponder positions were monitored for 8 min and combined with previously measured data on prostate position relative to skin marks. Margins were determined for situations of (1) skin-based positioning, and (2) pretreatment transponder positioning. Intratreatment intervention was simulated assuming conditions of (1) continuous tracking, and (2) a 3-mm threshold for position correction. Results: For skin-based setup without and with inclusion of intrafraction motion, prostate treatments would have required average margins of 8.0, 7.3, and 10.0 mm and 8.2, 10.2, and 12.5 mm, about the left-right, anterior-posterior, and cranial-caudal directions, respectively. Positioning by prostate markers at the start of the treatment fraction reduced these values to 1.8, 5.8, and 7.1 mm, respectively. Interbeam adjustment further reduced margins to an average of 1.4, 2.3, and 1.8 mm. Intrabeam adjustment yielded margins of 1.3, 1.5, and 1.5 mm, respectively. Conclusion: Significant reductions in margins might be achieved by repositioning the patient before each beam, either radiographically or electromagnetically. However, 2 of the 11 patients would have benefited from continuous target tracking and threshold-based intervention.

  2. Achieving Goal Blood Pressure.

    PubMed

    Laurent, Stéphane

    2015-07-01

    Both monotherapy and combination therapy options are appropriate for antihypertensive therapy according to the 2013 European Society of Hypertension (ESH)/European Society of Cardiology (ESC) guidelines. Most patients require more than one agent to achieve blood pressure (BP) control, and adding a second agent is more effective than doubling the dose of existing therapy. The addition of a third agent may be required to achieve adequate BP reductions in some patients. Single-pill fixed-dose combinations (FDCs) allow multiple-drug regimens to be delivered without any negative impact on patient compliance or persistence with therapy. FDCs also have documented beneficial clinical effects and use of FDCs containing two or three agents is recommended by the 2013 ESH/ESC guidelines. PMID:26002423

  3. Incisal margin condition after LEEP for cervical intraepithelial neoplasia patients and prognosis

    PubMed Central

    Chen, Hong; Liu, Xiufeang; Xu, Lina

    2016-01-01

    The aim of the study was to examine the relationship between incisal condition after loop electrosurgical excision procedure (LEEP) operation for cervical intraepithelial neoplasia (CIN) patients and prognosis. A study of high-risk incisal margin positive cases was also performed. We compared the differences in the prognosis of the 1-year follow-up visit in the 120 CIN patients admitted to the hospital during the period from April 2013 to April 2014. A total of 43 cases of positive incisal margin (35.8%), and 77 negative cases were included in the study. The differences in age, course of disease, and CIN level between the two groups showed no statistical significance (P>0.05). In the positive group, the positive ratio was significantly higher than that of the negative group (P<0.05). The positive incisal margin showed a significant positive correlation with human papillomavirus (HPV) positivity (r=0.327, P=0.035). The condition of most patients with positive incisal margin and HPV was critical, which was followed by positive incisal margin and negative HPV. The patients with the best prognosis were those with significant negative incisal margin as well as HPV (P<0.05). In conclusion, the positive incisal margin after LEEP operation was associated with relapse of the disease. Thus, considering the HPV test into consideration is valuable for the prognosis of the disease. PMID:27446314

  4. Negative-ion source applications.

    PubMed

    Ishikawa, J

    2008-02-01

    In this paper heavy negative-ion sources which we developed and their applications for materials science are reviewed. Heavy negative ions can be effectively produced by the ejection of a sputtered atom through the optimally cesiated surface of target with a low work function. Then, enough continuous negative-ion currents for materials-science applications can be obtained. We developed several kinds of sputter-type heavy negative-ion sources such as neutral- and ionized-alkaline metal bombardment-type heavy negative-ion source and rf-plasma sputter type. In the case where a negative ion is irradiated on a material surface, surface charging seldom takes place because incoming negative charge of the negative ion is well balanced with outgoing negative charge of the released secondary electron. In the negative-ion implantation into an insulator or insulated conductive material, high precision implantation processing with charge-up free properties can be achieved. Negative-ion implantation technique, therefore, can be applied to the following novel material processing systems: the surface modification of micrometer-sized powders, the nanoparticle formation in an insulator for the quantum devices, and the nerve cell growth manipulation by precise control of the biocompatibility of polymer surface. When a negative ion with low kinetic energy approaches the solid surface, the kinetic energy causes the interatomic bonding (kinetic bonding), and formation of a metastable material is promoted. Carbon films with high constituent of sp(3) bonding, therefore, can be formed by carbon negative-ion beam deposition. PMID:18315249

  5. Marginalized Youth in Contemporary Educational Contexts: A Tranquil Invitation to a Rebellious Celebration

    ERIC Educational Resources Information Center

    Furlong, Andy; Ferguson, Bruce; Tilleczek, Kate

    2010-01-01

    When any groups are systematically excluded from meaningful participation and achieve below their levels of competence, they become both "marginalized" in their current school environments and economically and socially disadvantaged over their lifetimes. For many young people, these intersecting marginalities come in the form of lowered…

  6. Revenue Neutral Water Conservation: Marginal Cost Pricing With Discount Coupons

    NASA Astrophysics Data System (ADS)

    Collinge, Robert A.

    1992-03-01

    This paper points out how a system of marketable discount coupons applied to the sale of water by an agency can satisfy both redistributional and revenue constraints without compromise to economic efficiency, in effect creating marketable multipart pricing. This procedure achieves marginal cost pricing for each user while decreasing the average consumer's expenditures on water. Efficiency would obtain both in allocation among users and in overall usage. No information on consumer demand for water is required. A useful by-product is market revelation of the marginal value of incremental water usage, thereby also shedding light on the value of incremental water projects.

  7. [Surgical margin status in hepatectomy for liver tumors].

    PubMed

    Salloum, C; Castaing, D

    2008-12-01

    It is admitted that only complete tumor clearance with negative surgical margins provides benefit for patients undergoing surgery for hepatobiliary malignancies. For hepatocellular carcinoma, since micrometastases disseminate via portal venous branches, anatomic resection is preferred over non-anatomic resection in liver resection carried out with curative intent. Thus, an anatomic liver resection with a wider resection margin theoretically gives a higher potential for cure. However, preserving non-tumorous liver parenchyma is an important consideration, especially in cirrhotic liver resection to decrease the incidence of postoperative liver failure. The optimal liver resection margin is still controversial. It seems that a resection margin of 2 cm is associated with a decreased postoperative recurrence rate and improved survival outcomes especially for hepatocellular carcinoma margins should not exclude patients from potentially curative surgery, and should not be used as a reason to establish palliative treatment instead since R1 resection is compatible with long-term survival. Aggressive hepatic surgery could and should therefore be performed if the peri-operative mortality is low. For hilar cholangiocarcinoma, surgical radicality has been shown in multivariate analyses of multiples studies to be the only parameter with a significant impact on survival. Extended right-side hepatectomies seems to give the best oncologic results. A predicted margin of < 1 cm after resection of hepatic colorectal metastases should not be used as an exclusion criterion for resection and will not impair patients' prognosis. Resection should be performed whatever the width of the surgical margin, rather than not performing the resection at all. PMID

  8. Childhood Obesity and Cognitive Achievement.

    PubMed

    Black, Nicole; Johnston, David W; Peeters, Anna

    2015-09-01

    Obese children tend to perform worse academically than normal-weight children. If poor cognitive achievement is truly a consequence of childhood obesity, this relationship has significant policy implications. Therefore, an important question is to what extent can this correlation be explained by other factors that jointly determine obesity and cognitive achievement in childhood? To answer this question, we exploit a rich longitudinal dataset of Australian children, which is linked to national assessments in math and literacy. Using a range of estimators, we find that obesity and body mass index are negatively related to cognitive achievement for boys but not girls. This effect cannot be explained by sociodemographic factors, past cognitive achievement or unobserved time-invariant characteristics and is robust to different measures of adiposity. Given the enormous importance of early human capital development for future well-being and prosperity, this negative effect for boys is concerning and warrants further investigation. PMID:26123250

  9. Isotropic Negative Thermal Expansion Metamaterials.

    PubMed

    Wu, Lingling; Li, Bo; Zhou, Ji

    2016-07-13

    Negative thermal expansion materials are important and desirable in science and engineering applications. However, natural materials with isotropic negative thermal expansion are rare and usually unsatisfied in performance. Here, we propose a novel method to achieve two- and three-dimensional negative thermal expansion metamaterials via antichiral structures. The two-dimensional metamaterial is constructed with unit cells that combine bimaterial strips and antichiral structures, while the three-dimensional metamaterial is fabricated by a multimaterial 3D printing process. Both experimental and simulation results display isotropic negative thermal expansion property of the samples. The effective coefficient of negative thermal expansion of the proposed models is demonstrated to be dependent on the difference between the thermal expansion coefficient of the component materials, as well as on the circular node radius and the ligament length in the antichiral structures. The measured value of the linear negative thermal expansion coefficient of the three-dimensional sample is among the largest achieved in experiments to date. Our findings provide an easy and practical approach to obtaining materials with tunable negative thermal expansion on any scale. PMID:27333052

  10. Structural design/margin assessment

    NASA Technical Reports Server (NTRS)

    Ryan, R. S.

    1993-01-01

    Determining structural design inputs and the structural margins following design completion is one of the major activities in space exploration. The end result is a statement of these margins as stability, safety factors on ultimate and yield stresses, fracture limits (fracture control), fatigue lifetime, reuse criteria, operational criteria and procedures, stability factors, deflections, clearance, handling criteria, etc. The process is normally called a load cycle and is time consuming, very complex, and involves much more than structures. The key to successful structural design is the proper implementation of the process. It depends on many factors: leadership and management of the process, adequate analysis and testing tools, data basing, communications, people skills, and training. This process and the various factors involved are discussed.

  11. Strongly Accelerated Margination of Active Particles in Blood Flow.

    PubMed

    Gekle, Stephan

    2016-01-19

    Synthetic nanoparticles and other stiff objects injected into a blood vessel filled with red blood cells are known to marginate toward the vessel walls. By means of hydrodynamic lattice-Boltzmann simulations, we show that active particles can strongly accelerate their margination by moving against the flow direction: particles located initially in the channel center migrate much faster to their final position near the wall than in the nonactive case. We explain our findings by an enhanced rate of collisions between the stiff particles and the deformable red blood cells. Our results imply that a significantly faster margination can be achieved either technically by the application of an external magnetic field (if the particles are magnetic) or biologically by self-propulsion (if the particles are, e.g., swimming bacteria). PMID:26789773

  12. [Marginality, ethnic groups and health].

    PubMed

    Corretger, J M; Fortuny, C; Botet, F; Valls, O

    1992-06-01

    Main marginated ethnic groups in Span are to be found among gypsies and 3rd world immigrants. The first group include about 250,000 persons and the second group more tan half a million people. Their origins and their being past of the less fortunate social layers made them a group of health risk. Pediatric pathologies are those favored by socio-economic shortcomings as well as hygienic-sanitary deficiencies. Imported pediatric pathologies have a small incident. PMID:1636945

  13. Addressing the Marginalized Student: The Secondary Principal's Role in Eliminating Deficit Thinking

    ERIC Educational Resources Information Center

    Simone, Joseph Anthony

    2012-01-01

    As federal mandates purport to improve the academic achievement of all students, the achievement gap between White students and their marginalized peers has not closed. The persistency of the gap raises the notion that the answer to addressing the achievement gap may not lie in policies or practices. The alternative then is to explore the…

  14. Students' Achievement Goals, Learning-Related Emotions and Academic Achievement.

    PubMed

    Lüftenegger, Marko; Klug, Julia; Harrer, Katharina; Langer, Marie; Spiel, Christiane; Schober, Barbara

    2016-01-01

    In the present research, the recently proposed 3 × 2 model of achievement goals is tested and associations with achievement emotions and their joint influence on academic achievement are investigated. The study was conducted with 388 students using the 3 × 2 Achievement Goal Questionnaire including the six proposed goal constructs (task-approach, task-avoidance, self-approach, self-avoidance, other-approach, other-avoidance) and the enjoyment and boredom scales from the Achievement Emotion Questionnaire. Exam grades were used as an indicator of academic achievement. Findings from CFAs provided strong support for the proposed structure of the 3 × 2 achievement goal model. Self-based goals, other-based goals and task-approach goals predicted enjoyment. Task-approach goals negatively predicted boredom. Task-approach and other-approach predicted achievement. The indirect effects of achievement goals through emotion variables on achievement were assessed using bias-corrected bootstrapping. No mediation effects were found. Implications for educational practice are discussed. PMID:27199836

  15. Students’ Achievement Goals, Learning-Related Emotions and Academic Achievement

    PubMed Central

    Lüftenegger, Marko; Klug, Julia; Harrer, Katharina; Langer, Marie; Spiel, Christiane; Schober, Barbara

    2016-01-01

    In the present research, the recently proposed 3 × 2 model of achievement goals is tested and associations with achievement emotions and their joint influence on academic achievement are investigated. The study was conducted with 388 students using the 3 × 2 Achievement Goal Questionnaire including the six proposed goal constructs (task-approach, task-avoidance, self-approach, self-avoidance, other-approach, other-avoidance) and the enjoyment and boredom scales from the Achievement Emotion Questionnaire. Exam grades were used as an indicator of academic achievement. Findings from CFAs provided strong support for the proposed structure of the 3 × 2 achievement goal model. Self-based goals, other-based goals and task-approach goals predicted enjoyment. Task-approach goals negatively predicted boredom. Task-approach and other-approach predicted achievement. The indirect effects of achievement goals through emotion variables on achievement were assessed using bias-corrected bootstrapping. No mediation effects were found. Implications for educational practice are discussed. PMID:27199836

  16. Breast Conservation Therapy: The Influence of Molecular Subtype and Margins

    SciTech Connect

    Demirci, Senem; Broadwater, Gloria; Marks, Lawrence B.; Clough, Robert; Prosnitz, Leonard R.

    2012-07-01

    Purpose: To evaluate treatment results and prognostic factors, especially margin status and molecular subtype, in early-stage breast cancer patients treated with breast conservation therapy (BCT). Methods and Materials: The records of 1,058 Stage I or II breast cancer patients treated with BCT (surgical excision plus radiotherapy) at Duke University Medical Center, Durham, North Carolina, from 1985-2005 were retrospectively reviewed. Conventional receptor analyses were used as surrogate markers for molecular subtype classification (luminal A, luminal B, Her2 positive, and basal like). Actuarial estimates of overall survival (OS), cause-specific survival (CSS), failure-free survival, and locoregional control (LRC) were computed by use of Kaplan-Meier plots. We analyzed prognostic variables for significance using Cox proportional hazards univariate and multivariate analysis. The study was approved by the Duke University Medical Center Institutional Review Board. Results: The median age of the patients was 56 years (range, 18-89 years). Of the patients, 80% had T1 disease and 66% N0 disease pathologically. With a median follow-up of 9.8 years, an in-breast recurrence developed in 53 patients and 10 patients had nodal failure. For all patients, the 10-year CSS rate was 94%; LRC rate, 94%; and failure-free survival rate, 88%. Luminal A patients had a CSS rate of 95% and LRC rate of 99%. Basal-type patients appeared to do worse, with regard to both CSS rate (74%) and LRC rate (76%), but the numbers were small and the difference was not statistically significant. LRC rates of patients with negative margins (widely negative, close, and extent of margin not known) were virtually identical (93%, 96%, and 94%, respectively). Those with positive margins appeared to fare slightly worse based on LRC rate (88%), but again, the numbers were small and the difference was not statistically significant. Conclusions: BCT remains the treatment of choice for early-stage breast cancer

  17. Demographic marginalization, social integration, and adolescents' educational success.

    PubMed

    Benner, Aprile D; Wang, Yijie

    2014-10-01

    Links between schools' demographic composition and students' achievement have been a major policy interest for decades. Using a racially/ethnically diverse sample from the National Longitudinal Study of Adolescent Health (N = 6,302; 54% females; 53% White, 21% African American, 15% Latino, 8% Asian American, 2% other race/ethnicity), we examined the associations between demographic marginalization, students' later social integration (loneliness at school, school attachment), and educational performance and attainment. Adolescents who were socioeconomically marginalized at school [i.e., having <15% same-socioeconomic status (SES) peers] had lower cumulative grade point averages across high school and lower educational attainment. A similar disadvantage was observed among students who were both socioeconomically and racially/ethnically marginalized at school (i.e., having <15% same-SES peers and <15% same-racial/ethnic peers). Indirect effects were also observed, such that demographic marginalization was linked to poorer school attachment, and poorer school attachment, in turn, was related to poorer academic performance. These results highlight the educational barriers associated with demographic marginalization and suggest potential targets for future intervention efforts. PMID:25034249

  18. Influence of margin status and radiation on recurrence after radical hysterectomy in Stage IB cervical cancer

    SciTech Connect

    Viswanathan, Akila N. . E-mail: aviswanathan@partners.org; Lee, Hang; Hanson, Emily; Berkowitz, Ross S.; Crum, Christopher P.

    2006-08-01

    Purpose: To examine the relationship between margin status and local recurrence (LR) or any recurrence after radical hysterectomy (RH) in women treated with or without radiotherapy (RT) for Stage IB cervical carcinoma. Methods and Materials: This study included 284 patients after RH with assessable margins between 1980 and 2000. Each margin was scored as negative ({>=}1 cm), close (>0 and <1 cm), or positive. The outcomes measured were any recurrence, LR, and relapse-free survival. Results: The crude rate for any recurrence was 11%, 20%, and 38% for patients with negative, close, and positive margins, respectively. The crude rate for LR was 10%, 11%, and 38%, respectively. Postoperative RT decreased the rate of LR from 10% to 0% for negative, 17% to 0% for close, and 50% to 25% for positive margins. The significant predictors of decreased relapse-free survival on univariate analysis were the depth of tumor invasion (hazard ratio [HR] 2.14/cm increase, p = 0.007), positive margins (HR 3.92, p = 0.02), tumor size (HR 1.3/cm increase, p = 0.02), lymphovascular invasion (HR 2.19, p = 0.03), and margin status (HR 0.002/increasing millimeter from cancer for those with close margins, p = 0.03). Long-term side effects occurred in 8% after RH and 19% after RH and RT. Conclusion: The use of postoperative RT may decrease the risk of LR in patients with close paracervical margins. Patients with other adverse prognostic factors and close margins may also benefit from the use of postoperative RT. However, RT after RH may increase the risk of long-term side effects.

  19. Impact of Margin Status on Local Recurrence After Mastectomy for Ductal Carcinoma In Situ

    SciTech Connect

    Childs, Stephanie K.; Chen, Yu-Hui; Duggan, Margaret M.; Golshan, Mehra; Pochebit, Stephen; Punglia, Rinaa S.; Wong, Julia S.; Bellon, Jennifer R.

    2013-03-15

    Purpose: To examine the rate of local recurrence according to the margin status for patients with pure ductal carcinoma in situ (DCIS) treated by mastectomy. Methods and Materials: One hundred forty-five consecutive women who underwent mastectomy with or without radiation therapy for DCIS from 1998 to 2005 were included in this retrospective analysis. Only patients with pure DCIS were eligible; patients with microinvasion were excluded. The primary endpoint was local recurrence, defined as recurrence on the chest wall; regional and distant recurrences were secondary endpoints. Outcomes were analyzed according to margin status (positive, close (≤2 mm), or negative), location of the closest margin (superficial, deep, or both), nuclear grade, necrosis, receptor status, type of mastectomy, and receipt of hormonal therapy. Results: The primary cohort consisted of 142 patients who did not receive postmastectomy radiation therapy (PMRT). For those patients, the median follow-up time was 7.6 years (range, 0.6-13.0 years). Twenty-one patients (15%) had a positive margin, and 23 patients (16%) had a close (≤2 mm) margin. The deep margin was close in 14 patients and positive in 6 patients. The superficial margin was close in 13 patients and positive in 19 patients. One patient experienced an isolated invasive chest wall recurrence, and 1 patient had simultaneous chest wall, regional nodal, and distant metastases. The crude rates of chest wall recurrence were 2/142 (1.4%) for all patients, 1/21 (4.8%) for those with positive margins, 1/23 (4.3%) for those with close margins, and 0/98 for patients with negative margins. PMRT was given as part of the initial treatment to 3 patients, 1 of whom had an isolated chest wall recurrence. Conclusions: Mastectomy for pure DCIS resulted in a low rate of local or distant recurrences. Even with positive or close mastectomy margins, the rates of chest wall recurrences were so low that PMRT is likely not warranted.

  20. Positive anterior margins in breast conserving surgery: Does it matter? A systematic review of the literature.

    PubMed

    Ang, Su C; Tapia, Grace; Davidson, Emily J; Kahramangil, Bora; Mak, Cindy; Carmalt, Hugh; Warrier, Sanjay

    2016-06-01

    Positive margins are associated with an increased risk of ipsilateral breast tumor recurrence (IBTR); therefore re-excision of positive margins is recommended. Involvement of anatomically non-breast margins, such as anterior margins, has been associated to a lower risk of IBTR than radial margins. Although many surgeons do not re-excise positive anterior margins (PAM); there is no consensus regarding this approach. The objective of this study is to find evidence that assesses this practice. A systemic literature review was performed through six databases from January 1995 to July 2014. Studies that discussed anatomical location of involved margins in BCS were included. Six studies were identified evaluating PAM. One study reported a 2.5% rate of IBTR in patients with non-negative margins treated with radiotherapy (of which 23% had a PAM). Another study showed 4% of residual disease after re-excision of PAM, but did not report IBTR rates. A later observational study reported that 87.5% of positive anterior and posterior margins were re-excised. One survey from America and one from the UK showed that 47% and 71% of surgeons would not re-excise PAM, respectively. A later survey in the UK reported that 43.8% of surgeons would not re-excise PAM in DCIS, whilst 29.2% would not for invasive carcinoma. Common surgical practices to not re-excise PAM contradict current guidelines that recommend obtaining negative margins to reduce the risk of IBTR. However, there is little evidence detailing the relationship between PAM and IBTR rates. Low residual disease after re-excision of PAM supports the limited benefit of re-excise this margin; however further studies are required to evaluate this topic. PMID:27060552

  1. Achievement Goals and Discrete Achievement Emotions: A Theoretical Model and Prospective Test

    ERIC Educational Resources Information Center

    Pekrun, Reinhard; Elliot, Andrew J.; Maier, Markus A.

    2006-01-01

    A theoretical model linking achievement goals to discrete achievement emotions is proposed. The model posits relations between the goals of the trichotomous achievement goal framework and 8 commonly experienced achievement emotions organized in a 2 (activity/outcome focus) x 2 (positive/negative valence) taxonomy. Two prospective studies tested…

  2. The Influence of Poverty on Achievement

    ERIC Educational Resources Information Center

    Tienken, Christopher H.

    2012-01-01

    Without a doubt, poverty has a negative influence on student achievement, especially when achievement is measured by state-mandated standardized tests. However, some bureaucrats, such as state commissioners of education and even state governors, continue to downplay the influence of poverty on student achievement. New Jersey's Governor Chris…

  3. Silenced, Silence, Silent: Motherhood in the Margins

    ERIC Educational Resources Information Center

    Carpenter, Lorelei; Austin, Helena

    2007-01-01

    This project explores the experiences of women who mother children with ADHD. The authors use the metaphor of the text and the margin. The text is the "motherhood myth" that describes a particular sort of "good" mothering. The margin is the space beyond that text. This marginal space is inhabited by some or all of the mothers they spoke with, some…

  4. The clinical significance of marginal fit.

    PubMed

    Larson, Thomas D

    2012-01-01

    Clinical evaluation of restoration acceptability includes marginal adaptation, restoration and preservation of anatomic form, color match, cavosurface discoloration, and presence of marginal caries. This paper will review what is known about marginal fit of all materials relative to their acceptable fit. Some explanation will be given of how material properties affect marginal fit, what the expected longevity of different materials is relative to marginal fit, and how marginal fit affects development of secondary or marginal caries. Marginal fit is assumed to affect restoration longevity by either encouraging or discouraging microleakage and development of secondary or marginal caries. Marginal fit and its effect on the health of the gingival tissues have been reviewed in an earlier paper on polishing and will not be reviewed here. Is there some correlation between marginal fit of the various materials used in restorative dentistry and this assumption? This paper will review the literature found on Medline and present the science behind the clinical significance of marginal fit utilizing in vitro studies where necessary and in vivo studies whenever possible. Numerous authors replicating these studies are used to improve reliability and replicability. PMID:22439529

  5. Diminishing Marginal Utility in Economics Textbooks

    ERIC Educational Resources Information Center

    Dittmer, Timothy

    2005-01-01

    Many introductory microeconomics textbook authors derive the law of demand from the assumption of diminishing marginal utility. Authors of intermediate and graduate textbooks derive demand from diminishing marginal rate of substitution and ordinal preferences. These approaches are not interchangeable; diminishing marginal utility for all goods is…

  6. 17 CFR 31.18 - Margin calls.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 1 2010-04-01 2010-04-01 false Margin calls. 31.18 Section 31....18 Margin calls. (a) No leverage transaction merchant shall liquidate a leverage contract because of a margin deficiency without effecting personal contact with the leverage customer. If a...

  7. 17 CFR 31.18 - Margin calls.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 17 Commodity and Securities Exchanges 1 2011-04-01 2011-04-01 false Margin calls. 31.18 Section 31....18 Margin calls. (a) No leverage transaction merchant shall liquidate a leverage contract because of a margin deficiency without effecting personal contact with the leverage customer. If a...

  8. Surgical Margins and the Risk of Local-Regional Recurrence After Mastectomy Without Radiation Therapy

    SciTech Connect

    Childs, Stephanie K.; Chen Yuhui; Duggan, Margaret M.; Golshan, Mehra; Pochebit, Stephen; Wong, Julia S.; Bellon, Jennifer R.

    2012-12-01

    Purpose: Although positive surgical margins are generally associated with a higher risk of local-regional recurrence (LRR) for most solid tumors, their significance after mastectomy remains unclear. We sought to clarify the influence of the mastectomy margin on the risk of LRR. Methods and Materials: The retrospective cohort consisted of 397 women who underwent mastectomy and no radiation for newly diagnosed invasive breast cancer from 1998-2005. Time to isolated LRR and time to distant metastasis (DM) were evaluated by use of cumulative-incidence analysis and competing-risks regression analysis. DM was considered a competing event for analysis of isolated LRR. Results: The median follow-up was 6.7 years (range, 0.5-12.8 years). The superficial margin was positive in 41 patients (10%) and close ({<=}2 mm) in 56 (14%). The deep margin was positive in 23 patients (6%) and close in 34 (9%). The 5-year LRR and DM rates for all patients were 2.4% (95% confidence interval, 0.9-4.0) and 3.5% (95% confidence interval, 1.6-5.3) respectively. Fourteen patients had an LRR. Margin status was significantly associated with time to isolated LRR (P=.04); patients with positive margins had a 5-year LRR of 6.2%, whereas patients with close margins and negative margins had 5-year LRRs of 1.5% and 1.9%, respectively. On univariate analysis, positive margins, positive nodes, lymphovascular invasion, grade 3 histology, and triple-negative subtype were associated with significantly higher rates of LRR. When these factors were included in a multivariate analysis, only positive margins and triple-negative subtype were associated with the risk of LRR. Conclusions: Patients with positive mastectomy margins had a significantly higher rate of LRR than those with a close or negative margin. However, the absolute risk of LRR in patients with a positive surgical margin in this series was low, and therefore the benefit of postmastectomy radiation in this population with otherwise favorable

  9. Three-dimensional marginal separation

    NASA Technical Reports Server (NTRS)

    Duck, Peter W.

    1988-01-01

    The three dimensional marginal separation of a boundary layer along a line of symmetry is considered. The key equation governing the displacement function is derived, and found to be a nonlinear integral equation in two space variables. This is solved iteratively using a pseudo-spectral approach, based partly in double Fourier space, and partly in physical space. Qualitatively, the results are similar to previously reported two dimensional results (which are also computed to test the accuracy of the numerical scheme); however quantitatively the three dimensional results are much different.

  10. Managing margins through physician engagement.

    PubMed

    Sears, Nicholas J

    2012-07-01

    Hospitals should take the following steps as they seek to engage physicians in an enterprisewide effort to effectively manage margins: Consider physicians' daily professional practice requirements and demands for time in balancing patient care and administrative duties. Share detailed transactional supply data with physicians to give them a behind-the-scenes look at the cost of products used for procedures. Institute physician-led management and monitoring of protocol compliance and shifts in utilization to promote clinical support for change. Select a physician champion to provide the framework for managing initiatives with targeted, efficient communication. PMID:22788036

  11. Continental margin tectonics - Forearc processes

    SciTech Connect

    Lundberg, N.; Reed, D.L. )

    1991-01-01

    Recent studies of convergent plate margins and the structural development of forearc terranes are summarized in a critical review of U.S. research from the period 1987-1990. Topics addressed include the geometry of accretionary prisms (Coulomb wedge taper and vertical motion in response to tectonic processes), offscraping vs underplating or subduction, the response to oblique convergence, fluids in forearc settings, the thermal framework and the effects of fluid advection, and serpentinite seamounts. Also included is a comprehensive bibliography for the period.

  12. Determination of pyrotechnic functional margin

    NASA Technical Reports Server (NTRS)

    Bement, Laurence J.; Schimmel, Morry L.

    1993-01-01

    Following the failure of a previously qualified pyrotechnically actuated pin puller design, an investigation led to a redesign and requalification. The emphasis of the second qualification was placed on determining the functional margin of the pin puller by comparing the energy deliverable by the pyrotechnic cartridge to the energy required to accomplish the function. Also determined were the effects of functional variables. This paper describes the failure investigation, the test methods employed and the results of the evaluation, and provides a recommended approach to assure the successful functioning of pyrotechnic devices.

  13. Determination of pyrotechnic functional margin

    NASA Technical Reports Server (NTRS)

    Bement, Laurence J.; Schimmel, Morry L.

    1992-01-01

    Following the failure of a previously qualified pyrotechnically actuated pin puller design, an investigation led to a redesign and requalification. The emphasis of the second qualification was placed on determining the functional margin of the pin puller by comparing the energy deliverable by the pyrotechnic cartridge to the energy required to accomplish the function. Also determined were the effects of functional variables. This paper describes the failure investigation, the test methods employed and the results of the evaluation, and provides a recommended approach to assure the successful functioning of pyrotechnic devices.

  14. Polarized negative ions

    SciTech Connect

    Haeberli, W.

    1981-04-01

    This paper presents a survey of methods, commonly in use or under development, to produce beams of polarized negative ions for injection into accelerators. A short summary recalls how the hyperfine interaction is used to obtain nuclear polarization in beams of atoms. Atomic-beam sources for light ions are discussed. If the best presently known techniques are incorporated in all stages of the source, polarized H/sup -/ and D/sup -/ beams in excess of 10 ..mu..A can probably be achieved. Production of polarized ions from fast (keV) beams of polarized atoms is treated separately for atoms in the H(25) excited state (Lamb-Shift source) and atoms in the H(1S) ground state. The negative ion beam from Lamb-Shift sources has reached a plateau just above 1 ..mu..A, but this beam current is adequate for many applications and the somewhat lower beam current is compensated by other desirable characteristics. Sources using fast polarized ground state atoms are in a stage of intense development. The next sections summarize production of polarized heavy ions by the atomic beam method, which is well established, and by optical pumping, which has recently been demonstrated to yield very large nuclear polarization. A short discussion of proposed ion sources for polarized /sup 3/He/sup -/ ions is followed by some concluding remarks.

  15. Marginal Lands: Concept, Assessment and Management

    SciTech Connect

    Kang, Shujiang; Post, Wilfred M; West, Tristram O.; Bandaru, Vara Prasad; Izaurralde, Dr. R. Cesar; Wang, Dali; Nichols, Dr Jeff A

    2013-01-01

    Marginal lands have received wide attention for their potential to improve food security and support bioenergy production. However, environmental, ecosystem service, and sustainability concerns have been widely raised over the use of marginal land. Knowledge of the extent, location, and quality of marginal lands as well as their assessment and management are limited and diverse. This paper provides a review of the historical development of marginal concept, its application and assessment. Limitations and priority research needs of marginal land assessment and management were discussed.

  16. The margitron: a generalized perceptron with margin.

    PubMed

    Panagiotakopoulos, Constantinos; Tsampouka, Petroula

    2011-03-01

    We identify the classical perceptron algorithm with margin as a member of a broader family of large margin classifiers, which we collectively call the margitron. The margitron, (despite its) sharing the same update rule with the perceptron, is shown in an incremental setting to converge in a finite number of updates to solutions possessing any desirable fraction of the maximum margin. We also report on experiments comparing the margitron with decomposition support vector machines, cutting-plane algorithms, and gradient descent methods on hard margin tasks involving linear kernels which are equivalent to 2-norm soft margin. Our results suggest that the margitron is very competitive. PMID:21216709

  17. Leukocyte margination at arteriole shear rate

    PubMed Central

    Takeishi, Naoki; Imai, Yohsuke; Nakaaki, Keita; Yamaguchi, Takami; Ishikawa, Takuji

    2014-01-01

    Abstract We numerically investigated margination of leukocytes at arteriole shear rate in straight circular channels with diameters ranging from 10 to 22 μm. Our results demonstrated that passing motion of RBCs effectively induces leukocyte margination not only in small channels but also in large channels. A longer time is needed for margination to occur in a larger channel, but once a leukocyte has marginated, passing motion of RBCs occurs continuously independent of the channel diameter, and leukocyte margination is sustained for a long duration. We also show that leukocytes rarely approach the wall surface to within a microvillus length at arteriole shear rate. PMID:24907300

  18. Marginally Relevant Topics in Conformal Field Theories

    NASA Astrophysics Data System (ADS)

    Cleary, Kevin Francis

    We consider a set of topics in conformal field theory. We provide an example of a 4D theory that exhibits the Contino-Pomarol-Rattazzi mechanism, where breaking conformal symmetry by an almost marginal operator leads to a light pseudo-Goldstone boson, the dilaton, and a parametrically suppressed contribution to vacuum energy. We consider SUSY QCD at the edge of the conformal window and break conformal symmetry by weakly gauging a subgroup of the flavor symmetry. Using Seiberg duality we show that for a range of parameters the singlet meson in the dual theory reaches the unitarity bound, however, this theory does not have a stable vacuum. We stabilize the vacuum with soft breaking terms, compute the mass of the dilaton, and determine the range of parameters where the leading contribution to the dilaton mass is from the almost marginal coupling. We also weigh in on a widely held belief that increasing bounds on the gluino mass, which feeds down to the stop mass through renormalization group running, are making a light stop increasingly unlikely. Here we present a counter-example. We examine the case of the Minimal Composite Supersymmetric Standard Model which has a light composite stop. The large anomalous dimension of the stop from strong dynamics pushes the stop mass toward a quasi-fixed point in the infrared, which is smaller than standard estimates by a factor of a large logarithm. The gluino can be about three times heavier than the stop, which is comparable to hierarchy achieved with supersoft Dirac gluino masses. Thus, in this class of models, a heavy gluino is not necessarily indicative of a heavy stop.

  19. Dynamics of the continental margins

    SciTech Connect

    Not Available

    1990-11-01

    On 18--20 June 1990, over 70 oceanographers conducting research in the ocean margins of North America attended a workshop in Virginia Beach, Virginia. The purpose of the workshop was to provide the Department of Energy with recommendations for future research on the exchange of energy-related materials between the coastal and interior ocean and the relationship between the ocean margins and global change. The workshop was designed to optimize the interaction of scientists from specific research disciplines (biology, chemistry, physics and geology) as they developed hypotheses, research questions and topics and implementation plans. The participants were given few restraints on the research they proposed other than realistic time and monetary limits. The interdisciplinary structure of the meeting promoted lively discussion and creative research plans. The meeting was divided into four working groups based on lateral, vertical, air/sea and sediment/water processes. Working papers were prepared and distributed before the meeting. During the meeting the groups revised the papers and added recommendations that appear in this report, which was reviewed by an Executive Committee.

  20. Social jetlag, academic achievement and cognitive performance: Understanding gender/sex differences.

    PubMed

    Díaz-Morales, Juan F; Escribano, Cristina

    2015-01-01

    Adolescents in high school suffer from circadian misalignment, undersleeping on weekdays and oversleeping on weekends. Since high schools usually impose early schedules, adolescents suffer from permanent social jetlag (SJL) and thus are a suitable population to study the effects of SJL on both academic and cognitive performance. In this study, 796 adolescents aged 12-16 years reported information about their sleep habits, morningness-eveningness (M-E), cognitive abilities and grade point average (GPA). Time in bed on both weekdays and weekends was not related to cognitive abilities, and only time in bed on weekdays was related to academic achievement. SJL was negatively related to academic achievement, cognitive abilities (except for vocabulary and verbal fluency abilities) and general cognitive ability (g), whereas M-E was slightly positively related to academic achievement and marginally negatively related to inductive reasoning. Results separated by sex/gender indicated that SJL may be more detrimental to girls' performance, as it was negatively related to a greater number of cognitive abilities and GPA. PMID:26061587

  1. Meningitis - gram-negative

    MedlinePlus

    Gram-negative meningitis ... Acute bacterial meningitis can be caused by Gram-negative bacteria. Meningococcal and H. influenzae meningitis are caused by Gram-negative bacteria and are covered in detail in other articles. This article ...

  2. Plasmonics without negative dielectrics

    NASA Astrophysics Data System (ADS)

    Della Giovampaola, Cristian; Engheta, Nader

    2016-05-01

    Plasmonic phenomena are exhibited in light-matter interaction involving materials whose real parts of permittivity functions attain negative values at operating wavelengths. However, such materials usually suffer from dissipative losses, thus limiting the performance of plasmon-based optical devices. Here, we utilize an alternative methodology that mimics a variety of plasmonic phenomena by exploiting the well-known structural dispersion of electromagnetic modes in bounded guided-wave structures filled with only materials with positive permittivity. A key issue in the design of such structures is prevention of mode coupling, which can be achieved by implementing thin metallic wires at proper interfaces. This method, which is more suitable for lower frequencies, allows designers to employ conventional dielectrics and highly conductive metals for which the loss is low at these frequencies, while achieving plasmonic features. We demonstrate, numerically and analytically, that this platform can provide surface plasmon polaritons, local plasmonic resonance, plasmonic cloaking, and epsilon-near-zero-based tunneling using conventional positive-dielectric materials.

  3. Northeast Atlantic Igneous Province volcanic margin development

    NASA Astrophysics Data System (ADS)

    Mjelde, R.; Breivik, A. J.; Faleide, J. I.

    2009-04-01

    Early Eocene continental breakup in the NE Atlantic Volcanic Province (NAIP) was associated with voluminous extrusive and intrusive magmatism, and initial seafloor spreading produced anomalously thick oceanic crust. Recent publications based on crustal-scale wide-angle seismic data show that there is a positive correlation between igneous crustal thickness (H) and average P-wave velocity (Vp) on all investigated margins in the NAIP. Vp can be used as a proxy for crustal composition, which can be related to the mode of mantle melting. A positive H-Vp correlation indicates that excessive mantle melting the first few million years after breakup was driven by an initial increased temperature that cools off as seafloor spreading develops, consistent with a mantle plume model. Variations in mantle composition can explain excess magmatism, but will generate a negative H-Vp correlation. Active mantle convection may increase the flux of mantle rocks through the melting zone above the rate of passive corner flow, which can also produce excessive magmatism. This would produce little H-Vp correlation, and place the curve lower than the passive flow melting curve in the diagram. We have compiled earlier published results with our own analyses of published and unpublished data from different groups to look for systematic variations in the mantle melting mode along the NAIP margins. Earlier studies (Holbrook et al., 2002, White et al, 2008) on the southeast Greenland conjugate system, indicate that the thick igneous crust of the southern NAIP (SE Greenland ? Hatton Bank) was dominated by increased mantle temperature only, while magmatism closer to the southern side of and including the Greenland-Iceland-Færøy Ridge (GIFR) was created by combined temperature increase and active mantle convection. Recent publications (Breivik et al., 2008, White et al, 2008) north of the GIFR for the Norway Basin segment, indicate temperature dominated magmatism between the Jan Mayen Fracture

  4. Impact of intraoperative specimen mammography on margins in breast-conserving surgery

    PubMed Central

    Hisada, Tomoka; Sawaki, Masataka; Ishiguro, Junko; Adachi, Yayoi; Kotani, Haruru; Yoshimura, Akiyo; Hattori, Masaya; Yatabe, Yasushi; Iwata, Hiroji

    2016-01-01

    A positive resection margin is one of the most significant risk factors for local breast cancer recurrence following breast-conserving surgery (BCS). Intraoperative specimen mammography (SMMG) is routinely used to evaluate the surgical margin at our institution. The aim of the present study was to assess the adequacy of SMMG for margin assessment. The patient cohort included 174 women who underwent BCS in 2006. The sensitivity and specificity of SMMG were assessed by comparing the margins assessed by histological and radiological methods. It was also examined whether the rate of positive histological margins was decreased by re-excision following SMMG evaluation. A total of 23 false-negatives and 6 false-positives were determined by SMMG. The sensitivity and specificity of SMMG margin assessment for patients with primary breast cancer were 20.6 and 94.6%, respectively. The positive predictive value was 50% and the negative predictive value was 82.2%. A subgroup analysis revealed that the sensitivity and specificity of SMMG in cases with ductal carcinoma in situ (DCIS) were higher compared with those in invasive ductal carcinoma. Furthermore, the positive histological margin rate was not affected by re-excision. Although the general usefulness of intraoperative SMMG was not proven, this procedure may be useful in specific cases, particularly those with DCIS and those diagnosed by stereotactic biopsy. A prospective study with exact criteria and a standard procedure is required. PMID:27588192

  5. Influence of surgical margins on overall survival after resection of intrahepatic cholangiocarcinoma

    PubMed Central

    Tang, Haowen; Lu, Wenping; Li, Bingmin; Meng, Xuan; Dong, Jiahong

    2016-01-01

    Abstract Background: Surgical resection is shown to present the best chance of cure in the treatment of intrahepatic cholangiocarcinoma (ICC). However, the appropriate length of the negative margin remains unclear. The aim of the present meta-analysis was to investigate whether a clear margin of 10 mm or more (≥10 mm) conferred any survival benefit over a margin of less than 10 mm (<10 mm) in patients with resected ICC. Methods: The meta-analysis was conducted in adherence with the PRISMA guidelines. PubMed, Web of Science, EMBASE, and the Cochrane Library were systematically searched to identify eligible studies published in English from the initiation of the databases to February 2016. Overall survival rates were pooled by using the hazard ratio and the corresponding 95% confidence interval (CI). Random-effect models were utilized because of between-study heterogeneity. Results: Six studies (eight cohorts) reporting on 712 patients were analyzed: 269 (37.80%) were in the 10 mm or more negative margin group, and 443 (62.20%) were in the less than 10 mm negative margin group. The pooled hazard ratio for the less than 10 mm group was found to be 1.59 (95% CI: 1.09–2.32) when this group was compared with the 10 mm or more group (reference), with moderate between-study heterogeneity (I2 = 45.30%, P = 0.07). Commensurate results were identified by sensitivity analysis. Conclusion: The result of this meta-analysis suggests a long-term survival (overall survival) advantage for negative margins of 10 mm or more in comparison with negative margins less than 10 mm for patients undergoing surgical resection of ICC. PMID:27583880

  6. Graded Achievement, Tested Achievement, and Validity

    ERIC Educational Resources Information Center

    Brookhart, Susan M.

    2015-01-01

    Twenty-eight studies of grades, over a century, were reviewed using the argument-based approach to validity suggested by Kane as a theoretical framework. The review draws conclusions about the meaning of graded achievement, its relation to tested achievement, and changes in the construct of graded achievement over time. "Graded…

  7. Magsat magnetic anomaly contrast across Labrador Sea passive margins

    NASA Technical Reports Server (NTRS)

    Bradley, Lauren M.; Frey, Herbert

    1991-01-01

    Many passive margins not complicated by nearby anomalous crustal structure have satellite elevation crustal magnetic anomaly contrasts across them that are recognizable in reduced-to-pole versions of the Magsat and POGO data. In the Labrador Sea region this contrast is particularly well developed with strong positive anomalies overlying the continental crust of Greenland and eastern Canada and prominent negative anomalies situated over the Labrador Sea and Baffin Bay. In this work, forward modeling of the large-scale crustal bodies in this region (continental, oceanic, passive margin, several anomalous structures) was used to show that the Magsat anomaly contrast is due simply to the change in crustal susceptibility and thickness at the continental/oceanic crustal transition. Because the thickness varies more than the average susceptibility from continental to oceanic crust, the strong anomaly contrast is essentially an edge effect due mostly to the change in crustal structure.

  8. Plasma 1-carbon metabolites and academic achievement in 15-yr-old adolescents.

    PubMed

    Nilsson, Torbjörn K; Hurtig-Wennlöf, Anita; Sjöström, Michael; Herrmann, Wolfgang; Obeid, Rima; Owen, Jennifer R; Zeisel, Steven

    2016-04-01

    Academic achievement in adolescents is correlated with 1-carbon metabolism (1-CM), as folate intake is positively related and total plasma homocysteine (tHcy) negatively related to academic success. Because another 1-CM nutrient, choline is essential for fetal neurocognitive development, we hypothesized that choline and betaine could also be positively related to academic achievement in adolescents. In a sample of 15-yr-old children (n= 324), we measured plasma concentrations of homocysteine, choline, and betaine and genotyped them for 2 polymorphisms with effects on 1-CM, methylenetetrahydrofolate reductase (MTHFR) 677C>T, rs1801133, and phosphatidylethanolamineN-methyltransferase (PEMT), rs12325817 (G>C). The sum of school grades in 17 major subjects was used as an outcome measure for academic achievement. Lifestyle and family socioeconomic status (SES) data were obtained from questionnaires. Plasma choline was significantly and positively associated with academic achievement independent of SES factors (paternal education and income, maternal education and income, smoking, school) and of folate intake (P= 0.009,R(2)= 0.285). With the addition of thePEMTrs12325817 polymorphism, the association value was only marginally changed. Plasma betaine concentration, tHcy, and theMTHFR677C>T polymorphism did not affect academic achievement in any tested model involving choline. Dietary intake of choline is marginal in many adolescents and may be a public health concern.-Nilsson, T. K., Hurtig-Wennlöf, A., Sjöström, M., Herrmann, W., Obeid, R., Owen, J. R., Zeisel, S. Plasma 1-carbon metabolites and academic achievement in 15-yr-old adolescents. PMID:26728177

  9. A Directed Acyclic Graph-Large Margin Distribution Machine Model for Music Symbol Classification.

    PubMed

    Wen, Cuihong; Zhang, Jing; Rebelo, Ana; Cheng, Fanyong

    2016-01-01

    Optical Music Recognition (OMR) has received increasing attention in recent years. In this paper, we propose a classifier based on a new method named Directed Acyclic Graph-Large margin Distribution Machine (DAG-LDM). The DAG-LDM is an improvement of the Large margin Distribution Machine (LDM), which is a binary classifier that optimizes the margin distribution by maximizing the margin mean and minimizing the margin variance simultaneously. We modify the LDM to the DAG-LDM to solve the multi-class music symbol classification problem. Tests are conducted on more than 10000 music symbol images, obtained from handwritten and printed images of music scores. The proposed method provides superior classification capability and achieves much higher classification accuracy than the state-of-the-art algorithms such as Support Vector Machines (SVMs) and Neural Networks (NNs). PMID:26985826

  10. A Directed Acyclic Graph-Large Margin Distribution Machine Model for Music Symbol Classification

    PubMed Central

    Wen, Cuihong; Zhang, Jing; Rebelo, Ana; Cheng, Fanyong

    2016-01-01

    Optical Music Recognition (OMR) has received increasing attention in recent years. In this paper, we propose a classifier based on a new method named Directed Acyclic Graph-Large margin Distribution Machine (DAG-LDM). The DAG-LDM is an improvement of the Large margin Distribution Machine (LDM), which is a binary classifier that optimizes the margin distribution by maximizing the margin mean and minimizing the margin variance simultaneously. We modify the LDM to the DAG-LDM to solve the multi-class music symbol classification problem. Tests are conducted on more than 10000 music symbol images, obtained from handwritten and printed images of music scores. The proposed method provides superior classification capability and achieves much higher classification accuracy than the state-of-the-art algorithms such as Support Vector Machines (SVMs) and Neural Networks (NNs). PMID:26985826

  11. Assessment of seismic margin calculation methods

    SciTech Connect

    Kennedy, R.P.; Murray, R.C.; Ravindra, M.K.; Reed, J.W.; Stevenson, J.D.

    1989-03-01

    Seismic margin review of nuclear power plants requires that the High Confidence of Low Probability of Failure (HCLPF) capacity be calculated for certain components. The candidate methods for calculating the HCLPF capacity as recommended by the Expert Panel on Quantification of Seismic Margins are the Conservative Deterministic Failure Margin (CDFM) method and the Fragility Analysis (FA) method. The present study evaluated these two methods using some representative components in order to provide further guidance in conducting seismic margin reviews. It is concluded that either of the two methods could be used for calculating HCLPF capacities. 21 refs., 9 figs., 6 tabs.

  12. Tectonic signatures on active margins

    NASA Astrophysics Data System (ADS)

    Hogarth, Leah Jolynn

    High-resolution Compressed High-Intensity Radar Pulse (CHIRP) surveys offshore of La Jolla in southern California and the Eel River in northern California provide the opportunity to investigate the role of tectonics in the formation of stratigraphic architecture and margin morphology. Both study sites are characterized by shore-parallel tectonic deformation, which is largely observed in the structure of the prominent angular unconformity interpreted as the transgressive surface. Based on stratal geometry and acoustic character, we identify three sedimentary sequences offshore of La Jolla: an acoustically laminated estuarine unit deposited during early transgression, an infilling or "healing-phase" unit formed during the transgression, and an upper transparent unit. The estuarine unit is confined to the canyon edges in what may have been embayments during the last sea-level rise. The healing-phase unit appears to infill rough areas on the transgressive surface that may be related to relict fault structures. The upper transparent unit is largely controlled by long-wavelength tectonic deformation due to the Rose Canyon Fault. This unit is also characterized by a mid-shelf (˜40 m water depth) thickness high, which is likely a result of hydrodynamic forces and sediment grain size. On the Eel margin, we observe three distinct facies: a seaward-thinning unit truncated by the transgressive surface, a healing-phase unit confined to the edges of a broad structural high, and a highly laminated upper unit. The seaward-thinning wedge of sediment below the transgressive surface is marked by a number of channels that we interpret as distributary channels based on their morphology. Regional divergence of the sequence boundary and transgressive surface with up to ˜8 m of sediment preserved across the interfluves suggests the formation of subaerial accommodation during the lowstand. The healing-phase, much like that in southern California, appears to infill rough areas in the

  13. Do the Teachers' Grading Practices Affect Student Achievement?

    ERIC Educational Resources Information Center

    Bonesronning, Hans

    2004-01-01

    The present paper explores empirically the relationship between teacher grading and student achievement. The hypothesis is that the teachers can manipulate student effort, and hence student achievement, by choosing the proper grading practices. The grading model is analogous to a labor supply model, where the teachers can set the marginal returns…

  14. SU-E-J-188: Theoretical Estimation of Margin Necessary for Markerless Motion Tracking

    SciTech Connect

    Patel, R; Block, A; Harkenrider, M; Roeske, J

    2015-06-15

    Purpose: To estimate the margin necessary to adequately cover the target using markerless motion tracking (MMT) of lung lesions given the uncertainty in tracking and the size of the target. Methods: Simulations were developed in Matlab to determine the effect of tumor size and tracking uncertainty on the margin necessary to achieve adequate coverage of the target. For simplicity, the lung tumor was approximated by a circle on a 2D radiograph. The tumor was varied in size from a diameter of 0.1 − 30 mm in increments of 0.1 mm. From our previous studies using dual energy markerless motion tracking, we estimated tracking uncertainties in x and y to have a standard deviation of 2 mm. A Gaussian was used to simulate the deviation between the tracked location and true target location. For each size tumor, 100,000 deviations were randomly generated, the margin necessary to achieve at least 95% coverage 95% of the time was recorded. Additional simulations were run for varying uncertainties to demonstrate the effect of the tracking accuracy on the margin size. Results: The simulations showed an inverse relationship between tumor size and margin necessary to achieve 95% coverage 95% of the time using the MMT technique. The margin decreased exponentially with target size. An increase in tracking accuracy expectedly showed a decrease in margin size as well. Conclusion: In our clinic a 5 mm expansion of the internal target volume (ITV) is used to define the planning target volume (PTV). These simulations show that for tracking accuracies in x and y better than 2 mm, the margin required is less than 5 mm. This simple simulation can provide physicians with a guideline estimation for the margin necessary for use of MMT clinically based on the accuracy of their tracking and the size of the tumor.

  15. Analysis of the Impact of Intraoperative Margin Assessment with Adjunctive Use of MarginProbe versus Standard of Care on Tissue Volume Removed

    PubMed Central

    Rivera, Ronald J.; Holmes, Dennis R.; Tafra, Lorraine

    2012-01-01

    Breast conserving surgery has been accepted as the optimal local therapy for women with early breast cancer, emphasizing the necessity to balance oncologic goals with patient satisfaction and cosmetic outcomes. In the move to enhance a surgeon's ability to achieve histologically clear margins intraoperatively at the initial surgery, the MarginProbe (Dune Medical Devices, Caesarea, Israel) has emerged as an effective tool to accomplish that task. Based on previously reported success using the device, we assessed cosmesis and tissue resection volumes among participants in a randomized-controlled trial comparing the standard of care lumpectomy performed with and without the MarginProbe. The use of the MarginProbe device resulted in a 57% reduction in reexcision rates compared to the control group with a small increase in tissue volume removed at the primary lumpectomy. When total tissue volumes removed were analyzed, the device and control groups were still very similar after normalization to bra cup size. We concluded that the MarginProbe is an effective device to assist surgeons in determining margin status intraoperatively while allowing for better patient cosmetic outcomes due to the smaller volumes of tissue resected and the reduction in patient referrals for second surgeries due to positive margins. PMID:23326653

  16. Attitudes and achievement of Bruneian science students

    NASA Astrophysics Data System (ADS)

    Dhindsa, Harkirat S.; Chung, Gilbert

    2003-08-01

    The aim of this study was to evaluate attitudes towards and achievement in science of Form 3 students studying in single-sex and coeducational schools in Brunei. The results demonstrated significant differences in attitudes towards and achievement in science of male and female students in single-sex schools and students in coeducational schools. These differences were at moderate level. In single-sex schools, the girls achieved moderately better in science than the boys despite their attitudes were only marginally better than the boys. However, there were no gender differences in attitudes towards and achievement in science of students in coeducational schools. The attitudes towards and achievement in science of girls in single-sex schools were moderately better than those of girls in coeducational schools. Whereas the attitudes towards and achievement in science of boys in single-sex schools were only marginally better than the boys in coeducational schools. However, further research to investigate (a) if these differences are repeated at other levels as well as in other subjects, and (b) the extent to which school type contributed towards these differences is recommended.

  17. Storm tracks near marginal stability

    NASA Astrophysics Data System (ADS)

    Ambaum, Maarten; Novak, Lenka

    2015-04-01

    The variance of atmospheric storm tracks is characterised by intermittent bursts of activity interspersed with relatively quiescent periods. Most of the poleward heat transport by storm tracks is due to a limited number of strong heat flux events, which occur in a quasi-periodic fashion. This behaviour is in contradiction with the usual conceptual model of the storm tracks, which relies on high growth rate background flows which then spawn weather systems that grow in an exponential or non-normal fashion. Here we present a different conceptual model of the atmospheric storm tracks which is built on the observation that, when including diabatic and other dissipative effects, the storm track region is in fact most of the time marginally stable. The ensuing model is a nonlinear oscillator, very similar to Volterra-Lotka predator-prey models. We demonstrate the extensions of this model to a stochastically driven nonlinear oscillator. The model produces quasi-periodic behaviour dominated by intermittent heat flux events. Perhaps most surprisingly, we will show strong evidence from re-analysis data for our conceptual model: the re-analysis data produces a phase-space plot that is very similar indeed to the phase-space plot for our nonlinear oscillator model.

  18. Constructions of Difference and Deficit, a Case Study: Nicaraguan Families and Children on the Margins in Costa Rica

    ERIC Educational Resources Information Center

    Purcell-Gates, Victoria

    2014-01-01

    This analysis examines the nexus of marginalization and education, particularly the literacy potential and achievement of young children from socially and politically marginalized communities. Drawing on data from a study of literacy practice among Nicaraguan immigrants in Costa Rica and the schooling of the Nicaraguan children in Costa Rican…

  19. Debating Values: Race, Class and Academic Achievement

    ERIC Educational Resources Information Center

    Milton, Penny

    2008-01-01

    The relationships among race, class and academic achievement are complex, yet have been well documented in Canada for the last thirty years. Generations of students have experienced them--lowered expectations for achievement, gross generalizations about parents' backgrounds and aspirations, negative stereotypes of communities, and curricula that…

  20. Stratigraphic signature of lithospheric deformation style in post-rift passive margin basins

    NASA Astrophysics Data System (ADS)

    Rouby, Delphine; Huismans, Ritske; Robin, Cecile; Braun, Jean; Granjeon, Didier

    2016-04-01

    We revise commonly accepted models explaining long-term stratigraphic trends along Atlantic-type passive margins by including the impact of complex lithosphere deformation at depth and it's coupling with surface processes. To achieve this, we simulated the evolution of a passive margin basin using a cascade of three modeling tools: a thermo-mechanical model of the syn-rift stretching of the lithosphere, a flexural and thermal model of the post-rift stage that includes coupling with surface processes and, finally, a stratigraphic model of the associated sedimentary basin architecture. We compare two necking styles that lead to different margin geometries: wide and narrow margins that form by heterogeneous stretching. Wide margins, forming thinner and wider sedimentary wedges, show significantly larger aggradation component and longer preservation duration, in more continental/proximal depositional facies. Narrow margins are characterized by enhanced erosion and by-pass during transgression. Through a parametric analysis we constrain the relative contribution of lithosphere deformation and surface processes on the stratigraphic trends and show that both may contribute equally to the stratigraphic architecture. For example, enhanced erosion in narrow margins impacts the volume of sediments delivered to the basin, which, in turn, significantly increases the subsidence. Our simulations also underline the importance of the assumed sediment transport length, which controls whether the main depocentres remain in the necking zone or reach the more distal parts of the margin.

  1. Tumor margin detection using optical biopsy techniques

    NASA Astrophysics Data System (ADS)

    Zhou, Yan; Liu, Cheng-hui; Li, Jiyou; Li, Zhongwu; Zhou, Lixin; Chen, Ke; Pu, Yang; He, Yong; Zhu, Ke; Li, Qingbo; Alfano, Robert R.

    2014-03-01

    The aim of this study is to use the Resonance Raman (RR) and fluorescence spectroscopic technique for tumor margin detection with high accuracy based on native molecular fingerprints of breast and gastrointestinal (GI) tissues. This tumor margins detection method utilizes advantages of RR spectroscopic technique in situ and in real-time to diagnose tumor changes providing powerful tools for clinical guiding intraoperative margin assessments and postoperative treatments. The tumor margin detection procedures by RR spectroscopy were taken by scanning lesion from center or around tumor region in ex-vivo to find the changes in cancerous tissues with the rim of normal tissues using the native molecular fingerprints. The specimens used to analyze tumor margins include breast and GI carcinoma and normal tissues. The sharp margin of the tumor was found by the changes of RR spectral peaks within 2 mm distance. The result was verified using fluorescence spectra with 300 nm, 320 nm and 340 nm excitation, in a typical specimen of gastric cancerous tissue within a positive margin in comparison with normal gastric tissues. This study demonstrates the potential of RR and fluorescence spectroscopy as new approaches with labeling free to determine the intraoperative margin assessment.

  2. Marginalization in Random Nonlinear Neural Networks

    NASA Astrophysics Data System (ADS)

    Vasudeva Raju, Rajkumar; Pitkow, Xaq

    2015-03-01

    Computations involved in tasks like causal reasoning in the brain require a type of probabilistic inference known as marginalization. Marginalization corresponds to averaging over irrelevant variables to obtain the probability of the variables of interest. This is a fundamental operation that arises whenever input stimuli depend on several variables, but only some are task-relevant. Animals often exhibit behavior consistent with marginalizing over some variables, but the neural substrate of this computation is unknown. It has been previously shown (Beck et al. 2011) that marginalization can be performed optimally by a deterministic nonlinear network that implements a quadratic interaction of neural activity with divisive normalization. We show that a simpler network can perform essentially the same computation. These Random Nonlinear Networks (RNN) are feedforward networks with one hidden layer, sigmoidal activation functions, and normally-distributed weights connecting the input and hidden layers. We train the output weights connecting the hidden units to an output population, such that the output model accurately represents a desired marginal probability distribution without significant information loss compared to optimal marginalization. Simulations for the case of linear coordinate transformations show that the RNN model has good marginalization performance, except for highly uncertain inputs that have low amplitude population responses. Behavioral experiments, based on these results, could then be used to identify if this model does indeed explain how the brain performs marginalization.

  3. 17 CFR 242.403 - Required margin.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Required margin. 242.403 Section 242.403 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION (CONTINUED) REGULATIONS M, SHO, ATS, AC, AND NMS AND CUSTOMER MARGIN REQUIREMENTS FOR SECURITY FUTURES Customer...

  4. 12 CFR 220.4 - Margin account.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... exceptions and special provisions. (2) Short sale against the box. A short sale “against the box” shall be treated as a long sale for the purpose of computing the equity and the required margin. (3) When-issued...) of this section as the amount to be added to the required margin in respect of short sales shall...

  5. Marginal Costing Techniques for Higher Education.

    ERIC Educational Resources Information Center

    Allen, Richard; Brinkman, Paul

    The techniques for calculating marginal costs in higher education are examined in detail. Marginal costs, as defined in economics, is the change in total cost associated with producing one additional unit of output. In higher education, the most frequently selected unit of output is a full-time-equivalent student or, alternatively, a student…

  6. Negative-ion states

    SciTech Connect

    Compton, R.N.

    1982-01-01

    In this brief review, we discuss some of the properties of atomic and molecular negative ions and their excited states. Experiments involving photon reactions with negative ions and polar dissociation are summarized. 116 references, 14 figures.

  7. Effect of Margin Design and Processing Steps on Marginal Adaptation of Captek Restorations

    PubMed Central

    Shih, Amy; Flinton, Robert; Vaidyanathan, Jayalakshmi; Vaidyanathan, Tritala

    2011-01-01

    This study examined the effect of four margin designs on marginal adaptation of Captek crowns during selected processing steps. Twenty-four Captek crowns were fabricated, six each of four margin designs: shoulder (Group A), chamfer (Group B), chamfer with bevel (Group C), and shoulder with bevel (Group D). Marginal discrepancies between crowns and matching dies were measured at selected points for each sample at the coping stage (Stage 1), following porcelain application (Stage 2) and cementation (Stage 3). Digital imaging methods were used to measure marginal gap. The results indicate decreasing trend of margin gap as a function of margin design in the order A>B>C>D. Between processing steps, the trend was in the order Stage 3 < Stage 1 < Stage 2. Porcelain firing had no significant effect on marginal adaptation, but cementation decreased the marginal gap. Generally, the margin gap in Captek restorations were in all cases less than the reported acceptable range of margin gaps for ceramometal restorations. These results are clinically favorable outcomes and may be associated with the ductility and burnishability of matrix phase in Captek metal coping margins. PMID:21991488

  8. Negative ion generator

    DOEpatents

    Stinnett, R.W.

    1984-05-08

    A negative ion generator is formed from a magnetically insulated transmission line having a coating of graphite on the cathode for producing negative ions and a plurality of apertures on the opposed anode for the release of negative ions. Magnetic insulation keeps electrons from flowing from the cathode to the anode. A transverse magnetic field removes electrons which do escape through the apertures from the trajectory of the negative ions. 8 figs.

  9. Negative ion generator

    DOEpatents

    Stinnett, Regan W.

    1984-01-01

    A negative ion generator is formed from a magnetically insulated transmission line having a coating of graphite on the cathode for producing negative ions and a plurality of apertures on the opposed anode for the release of negative ions. Magnetic insulation keeps electrons from flowing from the cathode to the anode. A transverse magnetic field removes electrons which do escape through the apertures from the trajectory of the negative ions.

  10. [Negative symptoms: which antipsychotics?].

    PubMed

    Maurel, M; Belzeaux, R; Adida, M; Azorin, J-M

    2015-12-01

    Treating negative symptoms of schizophrenia is a major issue and a challenge for the functional and social prognosis of the disease, to which they are closely linked. First- and second-generation antipsychotics allow a reduction of all negative symptoms. The hope of acting directly on primary negative symptoms with any antipsychotic is not supported by the literature. However, the effectiveness of first- and second-generation antipsychotics is demonstrated on secondary negative symptoms. PMID:26776390

  11. Sentential Negation in English

    ERIC Educational Resources Information Center

    Mowarin, Macaulay

    2009-01-01

    This paper undertakes a detailed analysis of sentential negation in the English language with Chomsky's Government-Binding theory of Transformational Grammar as theoretical model. It distinguishes between constituent and sentential negation in English. The essay identifies the exact position of Negation phrase in an English clause structure. It…

  12. A new bivariate negative binomial regression model

    NASA Astrophysics Data System (ADS)

    Faroughi, Pouya; Ismail, Noriszura

    2014-12-01

    This paper introduces a new form of bivariate negative binomial (BNB-1) regression which can be fitted to bivariate and correlated count data with covariates. The BNB regression discussed in this study can be fitted to bivariate and overdispersed count data with positive, zero or negative correlations. The joint p.m.f. of the BNB1 distribution is derived from the product of two negative binomial marginals with a multiplicative factor parameter. Several testing methods were used to check overdispersion and goodness-of-fit of the model. Application of BNB-1 regression is illustrated on Malaysian motor insurance dataset. The results indicated that BNB-1 regression has better fit than bivariate Poisson and BNB-2 models with regards to Akaike information criterion.

  13. Margin and complication rates in clampless partial nephrectomy: a comparison of open, laparoscopic and robotic surgeries.

    PubMed

    Mearini, Luigi; Nunzi, Elisabetta; Vianello, Alberto; Di Biase, Manuel; Porena, Massimo

    2016-06-01

    In performing partial nephrectomy (PN), surgeons focus on complete removal of tumor, preservation of renal function, the absence of major perioperative complications, expressed by the formula margin, ischemia and complication (MIC). The aim of current study was to perform a single-institution comparison of clampless open (OPN), laparoscopic (LPN) or robot-assisted (RAPN) PN as well as to evaluate pre-, intra- and postoperative factors that may influence achievement of ideal MIC. All consecutive clampless OPN, LPN or RAPN performed by experienced surgeons between 2006 and 2015 were included in the analysis. MIC was defined as negative surgical margin plus zero-ischemia plus absence of any grade ≥3 complications according to Clavien-Dindo classification. Bivariate and multivariate logistic regression models were fitted to predict the MIC. Odds ratios with 95 % confidence intervals were calculated. 80 patients underwent OPN, 66 LPN and 31 RAPN, and both groups had similar characteristics. The MIC rate was 67.5, 86.3 and 83.3 % in the OPN, LPN and RAPN groups, respectively (p = 0.016). At logistic regression analysis, surgical approach (p = 0.03) and operative time (p = 0.008) were independent predictors of the MIC rate. When stratified according to the surgical approach, preoperative aspects and dimensions used for an anatomical classification (PADUA) score, LPN, RAPN and operative time were independent predictors of MIC rate (p = 0.0488, p = 0.0494, p = 0.0479 and p = 0.0108, respectively). Clampless LPN and RAPN have an efficacy and safety profile that is on par with OPN, offering the additional benefits of a reduced operative time, blood loss, on demand ischemia and rate of high-grade complications. PMID:27083923

  14. Negative refraction without absorption via quantum coherence

    NASA Astrophysics Data System (ADS)

    Fang, Ai-Ping; Ge, Wenchao; Wang, Meng; Li, Fu-li; Zubairy, M. Suhail

    2016-02-01

    Negative refraction of a probe field is studied in a dense gas consisting of cascade-type four-level atoms. By coupling the magnetic component of the probe field to a Λ scheme with initially prepared coherence in the two lower levels, strong negative permeability with minimal absorption can be obtained. The permittivity of the gas to the electric component of the probe field can be made negative by taking into account the local field effect of the dense atoms. Strong negative refraction with zero absorption can be achieved in a wide range of parameters in our scheme. A possible experimental realization is also discussed.

  15. Investigation of a negative i-line resist with the CORE-2564 laser writer

    NASA Astrophysics Data System (ADS)

    Grenon, Brian J.; Sprout, Donna M.; Aaskov, William A.; Buck, Peter D.

    1994-12-01

    The process of record for mask fabrication on CORE pattern generators has been OCG-895i positive resist. This process has demonstrated excellent performance in a production environment, however it is recognized that having both negative and positive resist process capability would significantly improve the flexibility of most mask fabricators. The CORE exposure wavelength of 363.8 nm is close enough to i-line (365 nm) to provide the opportunity to use many of the i-line resists developed for wafer lithography. Negative acting resists sensitive at i-line are now becoming available. The most popular chemistry for this application has been acid catalyzed chemical amplification. These formulations typically contain a novolak resin, an acid generator, and a melamine crosslinking agent. The chemistry of such formulations has been previously described. An evaluation of OCG LMB-7011, an acid catalyzed chemically amplified negative i-line resist, has been conducted with the CORE-2564. This resist can be processed similarly to OCG-895i in standard mask process equipment, except that a post exposure bake is required to crosslink the exposed resist. With wet chrome etching, this resist exhibits exposure latitude similar or better than OCG-895i, benefiting from the fact that over-exposure is required to compensate for etch undercut when using a negative resist. Sub-micron resolution has been achieved with good linearity. CD control is marginal, due to a strong CD sensitivity to PEB temperature. A modified PEB process demonstrates improved CD control.

  16. New insights on shear margin gravitational evolution through time. The case of the equatorial margins

    NASA Astrophysics Data System (ADS)

    Loncke, L.; Basile, C.; Gaullier, V.; Maillard, A.; Patriat, M.; Sage, F.; Roest, W.

    2009-04-01

    30% of passive margins in the world correspond to shear margins. Unlike divergent margins, those margins present a very sharp ocean-continent boundary which is expressed by steep surface slopes and complex rift structures. In addition of tilted blocks, wrench and strike-slip faults frequently deform the continental crust. High marginal ridges, rising 1-3 km over the adjacent margin typically form along the continental side of the margin. The best known example of transform margin is the Côte d'Ivoire-Ghana margin, highly investigated in the 1980's. New observations along the French-Guiana shear margin (GUYAPLAC survey, 2003) have evidenced massive early (immediately after rifting) and late collapses of the margin. These collapses concern huge volumes: remobilized masses that reach nearly 15000 km3 have been identified in the abyssal plain. No marginal ridge has been observed there. These observations have been compared to results published for the Surinam prolongation of this shear segment (Gouyet, 1988; Erbacher et al., 2004). There also, collapses and slope instabilities are evident, though part of a marginal ridge remains present. Finally, published data from the western Côte d'Ivoire transform margin (De Caprona, 1992) show wide collapses, some deep-seated, and other shallow. Sinking of entire parts of shear margins by gravity collapses appears thus rather common. These observations show that the post-rift gravity collapse of shear margins has been largely underestimated, and has even not been considered in evolutional models of transform margins, despite the fact this has important implications on the geometry and balance of those margins. On the basis of these observations, we propose a tentative scenario for the equatorial Atlantic shear margin gravitational evolution. References: Gouyet, S., 1988. Evolution tectono-sédimentaire des marges guyannaise et Nord-Brésilienne au cours de l'ouverture de l'Atlantique Sud. PhD Thesis, univ Pau et des pays de l

  17. Perceived marginalization and aggression: a longitudinal study with low-educated adolescents.

    PubMed

    Issmer, Christian; Wagner, Ulrich

    2015-03-01

    Social exclusion can evoke aggression. In the past two decades research has demonstrated this effect both for interpersonal and societal forms of exclusion. In addition, recent violent uprisings, like the London riots in August 2011, have been linked to social exclusion in the media. However, so far there is a lack of longitudinal studies which examine the aggression-enhancing effect of societal-level exclusion (i.e., marginalization) in disadvantaged groups. This research investigates the impact of perceived marginalization on aggression in a sample of N = 181 adolescents with a low educational background by means of a two-wave longitudinal study. The results of structural equation analyses are consistent with the hypothesis that perceived marginalization enhances aggression, and that this effect is mediated by the extent of negative societal meta-stereotypes. Furthermore, the reverse path from aggression to perceptions of marginalization is also significant. We discuss the implications of these findings and highlight practical consequences. PMID:24889808

  18. Cenozoic ice volume and margin erosion

    SciTech Connect

    Miller, K.C.; Fairbanks, R.G.; Mountain, G.S.

    1985-01-01

    Cenozoic benthic foraminiferal oxygen isotopic data indicates that the world was glaciated in the early Oligocene, middle Oligocene, latest Oligocene, and middle Miocene to Recent, but are insufficient to resolve if the world was ice free at other times. The authors relate Oligocene and younger intervals of ice growth to continental margin erosional events. Relationships between eustasy and continental margin sedimentation are controversial. Coastal onlap is indirectly linked with rising sea level, occurring either when subsidence exceeds the rate of sea level fall or during sea-level rise. Although chronostratigraphic breaks are often local in origin, inter-regional unconformities result from eustatic lowerings. Strong evidence for eustatic lowerings is provided by the incision of canyons on margins. Chronostratigraphic breaks and canyons have noted on the US and Irish margins near the lower/upper Oligocene and middle/upper Miocene boundaries. These periods of margin erosion are temporally linked with oxygen isotopic evidence for ice growth, with erosion correlating with the greatest rate of ice growth. If the Eocene was ice free, there may have been mechanistic differences between Eocene erosion and Oligocene to Recent glacio-eustatic erosion. The authors present seismic stratigraphic evidence from the New Jersey margin that indicates contrasting styles of margin erosion between the Lower Tertiary and Upper Tertiary.

  19. Temporal Variation in Population Size of European Bird Species: Effects of Latitude and Marginality of Distribution

    PubMed Central

    Cuervo, José J.; Møller, Anders P.

    2013-01-01

    In the Northern Hemisphere, global warming has been shown to affect animal populations in different ways, with southern populations in general suffering more from increased temperatures than northern populations of the same species. However, southern populations are also often marginal populations relative to the entire breeding range, and marginality may also have negative effects on populations. To disentangle the effects of latitude (possibly due to global warming) and marginality on temporal variation in population size, we investigated European breeding bird species across a latitudinal gradient. Population size estimates were regressed on years, and from these regressions we obtained the slope (a proxy for population trend) and the standard error of the estimate (SEE) (a proxy for population fluctuations). The possible relationships between marginality or latitude on one hand and slopes or SEE on the other were tested among populations within species. Potentially confounding factors such as census method, sampling effort, density-dependence, habitat fragmentation and number of sampling years were controlled statistically. Population latitude was positively related to regression slopes independent of marginality, with more positive slopes (i.e., trends) in northern than in southern populations. The degree of marginality was positively related to SEE independent of latitude, with marginal populations showing larger SEE (i.e., fluctuations) than central ones. Regression slopes were also significantly related to our estimate of density-dependence and SEE was significantly affected by the census method. These results are consistent with a scenario in which southern and northern populations of European bird species are negatively affected by marginality, with southern populations benefitting less from global warming than northern populations, thus potentially making southern populations more vulnerable to extinction. PMID:24147048

  20. 12 CFR 220.12 - Supplement: margin requirements.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 3 2010-01-01 2010-01-01 false Supplement: margin requirements. 220.12 Section... SYSTEM CREDIT BY BROKERS AND DEALERS (REGULATION T) § 220.12 Supplement: margin requirements. The required margin for each security position held in a margin account shall be as follows: (a) Margin...

  1. 12 CFR 220.12 - Supplement: margin requirements.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 3 2011-01-01 2011-01-01 false Supplement: margin requirements. 220.12 Section... SYSTEM CREDIT BY BROKERS AND DEALERS (REGULATION T) § 220.12 Supplement: margin requirements. The required margin for each security position held in a margin account shall be as follows: (a) Margin...

  2. Dynamics and Correlations among Soft Excitations in Marginally Stable Glasses

    NASA Astrophysics Data System (ADS)

    Yan, Le; Baity-Jesi, Marco; Müller, Markus; Wyart, Matthieu

    2015-06-01

    Marginal stability is the notion that stability is achieved, but only barely so. This property constrains the ensemble of configurations explored at low temperature in a variety of systems, including spin, electron, and structural glasses. A key feature of marginal states is a (saturated) pseudogap in the distribution of soft excitations. We examine how such pseudogaps appear dynamically by studying the Sherrington-Kirkpatrick (SK) spin glass. After revisiting and correcting the multi-spin-flip criterion for local stability, we show that stationarity along the hysteresis loop requires soft spins to be frustrated among each other, with a correlation diverging as C (λ )˜1 /λ , where λ is the stability of the more stable spin. We explain how this arises spontaneously in a marginal system and develop an analogy between the spin dynamics in the SK model and random walks in two dimensions. We discuss analogous frustrations among soft excitations in short range glasses and how to detect them experimentally. We also show how these findings apply to hard sphere packings.

  3. Dynamics and Correlations among Soft Excitations in Marginally Stable Glasses.

    PubMed

    Yan, Le; Baity-Jesi, Marco; Müller, Markus; Wyart, Matthieu

    2015-06-19

    Marginal stability is the notion that stability is achieved, but only barely so. This property constrains the ensemble of configurations explored at low temperature in a variety of systems, including spin, electron, and structural glasses. A key feature of marginal states is a (saturated) pseudogap in the distribution of soft excitations. We examine how such pseudogaps appear dynamically by studying the Sherrington-Kirkpatrick (SK) spin glass. After revisiting and correcting the multi-spin-flip criterion for local stability, we show that stationarity along the hysteresis loop requires soft spins to be frustrated among each other, with a correlation diverging as C(λ)∼1/λ, where λ is the stability of the more stable spin. We explain how this arises spontaneously in a marginal system and develop an analogy between the spin dynamics in the SK model and random walks in two dimensions. We discuss analogous frustrations among soft excitations in short range glasses and how to detect them experimentally. We also show how these findings apply to hard sphere packings. PMID:26197008

  4. Cosmology with negative absolute temperatures

    NASA Astrophysics Data System (ADS)

    Vieira, J. P. P.; Byrnes, Christian T.; Lewis, Antony

    2016-08-01

    Negative absolute temperatures (NAT) are an exotic thermodynamical consequence of quantum physics which has been known since the 1950's (having been achieved in the lab on a number of occasions). Recently, the work of Braun et al. [1] has rekindled interest in negative temperatures and hinted at a possibility of using NAT systems in the lab as dark energy analogues. This paper goes one step further, looking into the cosmological consequences of the existence of a NAT component in the Universe. NAT-dominated expanding Universes experience a borderline phantom expansion (w < ‑1) with no Big Rip, and their contracting counterparts are forced to bounce after the energy density becomes sufficiently large. Both scenarios might be used to solve horizon and flatness problems analogously to standard inflation and bouncing cosmologies. We discuss the difficulties in obtaining and ending a NAT-dominated epoch, and possible ways of obtaining density perturbations with an acceptable spectrum.

  5. Negative Ion Density Fronts

    SciTech Connect

    Igor Kaganovich

    2000-12-18

    Negative ions tend to stratify in electronegative plasmas with hot electrons (electron temperature Te much larger than ion temperature Ti, Te > Ti ). The boundary separating a plasma containing negative ions, and a plasma, without negative ions, is usually thin, so that the negative ion density falls rapidly to zero-forming a negative ion density front. We review theoretical, experimental and numerical results giving the spatio-temporal evolution of negative ion density fronts during plasma ignition, the steady state, and extinction (afterglow). During plasma ignition, negative ion fronts are the result of the break of smooth plasma density profiles during nonlinear convection. In a steady-state plasma, the fronts are boundary layers with steepening of ion density profiles due to nonlinear convection also. But during plasma extinction, the ion fronts are of a completely different nature. Negative ions diffuse freely in the plasma core (no convection), whereas the negative ion front propagates towards the chamber walls with a nearly constant velocity. The concept of fronts turns out to be very effective in analysis of plasma density profile evolution in strongly non-isothermal plasmas.

  6. Radiofrequency ablation technique eradicating palpebral margin neoplasm

    PubMed Central

    Jiang, Tian-Yu; Wang, Xing-Lin; Suo, Wei; He, Qing-Hua; Xiao, Hong-Yu

    2011-01-01

    AIM To report the study on radiofrequency ablation technique for eradication of palpebral margin neoplasm and its clinical effects. METHODS One hundred and six cases with the palpebral margin neoplasm were performed surgical removal with radiofrequency ablation technique. The 1-2 months postoperative follow-up was investigated and the lost cases were excluded from statistics. The continuing follow-up lasted about 6-16months. RESULTS One hundred cases underwent one treatment and 6 cases underwent two treatments. Six cases were missed. All the cases followed up healed well without pigmentation or scar left, nor eyelash loss or palpebral margin deformation. No case was recurrent. CONCLUSION Radiofrequency ablation has significant efficiency in eradicating the palpebral margin neoplasm. PMID:22553639

  7. 17 CFR 31.18 - Margin calls.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... after contact is effected in which to respond to a margin call. Twenty-four hours, excluding Saturdays... contract for a period of 5 business days at the then prevailing bid price in the case of a long...

  8. 17 CFR 31.18 - Margin calls.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... after contact is effected in which to respond to a margin call. Twenty-four hours, excluding Saturdays... contract for a period of 5 business days at the then prevailing bid price in the case of a long...

  9. 17 CFR 31.18 - Margin calls.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... after contact is effected in which to respond to a margin call. Twenty-four hours, excluding Saturdays... contract for a period of 5 business days at the then prevailing bid price in the case of a long...

  10. Importance of surgical margins in rectal cancer.

    PubMed

    Mukkai Krishnamurty, Devi; Wise, Paul E

    2016-03-01

    Distal resection margin (DRM) and circumferential resection margin (CRM) are two important considerations in rectal cancer management. Although guidelines recommend a 2 cm DRM, studies have shown that a shorter DRM is adequate, especially in patients receiving neoadjuvant chemoradiation. Standardization of total mesorectal excision has greatly improved quality of CRM. Although more patients are undergoing sphincter-saving procedures, abdominoperineal resection is indicated for very distal tumors, and pelvic exenteration is often necessary for tumors involving pelvic organs. PMID:27094456

  11. Marginal accuracy of temporary composite crowns.

    PubMed

    Tjan, A H; Tjan, A H; Grant, B E

    1987-10-01

    An in vitro study was conducted to quantitatively compare the marginal adaptation of temporary crowns made from Protemp material with those made from Scutan, Provisional, and Trim materials. A direct technique was used to make temporary restorations on prepared teeth with an impression as a matrix. Protem, Trim, and Provisional materials produced temporary crowns of comparable accuracy. Crowns made from Scutan material had open margins. PMID:2959770

  12. Statistical Analysis of Thermal Analysis Margin

    NASA Technical Reports Server (NTRS)

    Garrison, Matthew B.

    2011-01-01

    NASA Goddard Space Flight Center requires that each project demonstrate a minimum of 5 C margin between temperature predictions and hot and cold flight operational limits. The bounding temperature predictions include worst-case environment and thermal optical properties. The purpose of this work is to: assess how current missions are performing against their pre-launch bounding temperature predictions and suggest any possible changes to the thermal analysis margin rules

  13. Parameter margins for stabilized conservative multilinear systems

    NASA Technical Reports Server (NTRS)

    Warren, Wayne; Wie, Bong

    1991-01-01

    Simple and elegant derivations of recent results concerning the computation of infinity-norm real-parameter margins for stabilized, mass-spring dynamical systems with the masses and the spring constraints as uncertain parameters are presented. The authors introduce the concept of critical frequency and gain for stabilized conservative systems whose uncertain parameters do not necessarily appear multilinearly in the numerator and denominator of the plant transfer function. An approach to parameter margin computation is presented.

  14. Inverse Modelling of Continental Margins and Sedimentary Basins

    NASA Astrophysics Data System (ADS)

    Edwards, G. R.; White, N.; Haines, J.

    2004-12-01

    The wealth of data available from the hydrocarbon industry provides us with detailed information about the subsidence histories of extensional sedimentary basins and passive margins. This resource is often exploited in forward models of basin and margin evolution although little attempt has been made to invert such data. We are interested in developing an inverse methodology in order to constrain the spatial and temporal variation of strain rate in these regions. Any inversion scheme which searches the possible movements of the lithosphere over geological time requires a fast forward model at its heart. We present a new kinematic model for use in such an inversion. Our finite-difference model is capable of simulating the thermal and subsidence effects of basins and margins that have undergone differential stretching with both depth and distance across the stretching area. Speed is achieved by a modular design and optimisation of the code for the architecture on which it is running. The model can simulate fifty million years of extension in around a second on a desktop computer. Currently there is much interest in cold continental margins such as the Newfoundland/Iberia system where crust has been thinned to zero but lithospheric mantle has been exhumed without extension. We believe this is not possible without differential thinning and will be testing this hypothesis with our new model. The inversion scheme is also being used to investigate flanks of actively rifting regions, such as those around Lake Baikal and the Albertine rift, and older extensional systems such as those in the Northern North sea.

  15. The basins on the Argentine continental margin

    SciTech Connect

    Urien, C.M.

    1996-08-01

    After the stabilization of the central Gondwana Craton, orogenic belts were accreted, as a result of convergence events and an extensive passive margin developed in southwestern Gondwana. Thermal subsidence in Parana, Karoo-Ventania basins and the Late Paleozoic-Early Mesozoic rifts, were modified by the Gondwana breakup and the South Atlantic opening. Early Paleozoic marine transgressions deposited the Table Mountain Group in Ventania. In southwestern Patagonia foreland clastics were deposited. Magmatic arcs and marine units indicate a tectonic trough was formed, alternating with continental sequences, over Late Paleozoic metamorphics and intrusives, resulting from plastered terrains along the Gondwana margin. In Patagonia, Permo-Carboniferous continental and glacio marine clastics infill the basins, while in Ventania, paralic sequences, grade from neritic to continental to the northeast, extending beneath the continental margin. The Triassic-Jurassic rift basins progressed onto regional widespread acid lavas and were infilled by lagoonal organic-rich sequences. Early drift phase built basins transverse to the margin, with fluvio-lacustrine sequences: Salado, Colorado, Valdes-Rawson, San Julian and North Malvinas intracratonic basins, which underwent transtensional faulting. Post-Oxfordian to Neocomian brackish sequences, onlapped the conjugate basins during the margin`s drift, with petroleum systems, as in Austral and Malvinas. In the Valanginian, basic extrusions commenced to form on the continental border, heralding the oceanic phase. Due to thermal subsidence, offlaping sediments prograded onto the remaining half-grabens. Several petroleum systems, proven and hypothetical, are identified in this region.

  16. The addiction to negativity.

    PubMed

    Lane, R C; Hull, J W; Foehrenbach, L M

    1991-01-01

    In this paper, we have described a type of resistance that has attracted increasing psychoanalytic attention in recent years. Patients exposed to intense negativity during early life may develop an addiction to negative experience as adolescents and adults, and this may constitute a central organizing feature of their personality. In almost all patients, however, some moments of negativity may be observed. We have traced the developmental origins of an attachment to negativity, drawing especially on psychoanalytic investigations of preoedipal pathology. Manifestations and derivatives of early negativity include anhedonia, attachment to physical pain, fear of success, masochism, deprivation of self and others, and negative voyeurism. In discussing the dynamic functions of negativity, we place particular emphasis on two motives: the patient's desires for revenge against early objects that have been a source of deprivation and frustration; and the defensive function of negativity in helping to express as well as ward off dangerous wishes to merge with the object. Deviant forms of autoerotism are likely to be used by these patients to deal with the reactivation of early experiences of neglect and rejection. When negativity is used as a defense or method of relating to others it can lead to a severe disruption of the psychotherapeutic relationship. We have reviewed suggestions for the management of extreme negativity in treatment. Resolution of the therapist's countertransference reactions, especially induced feelings of frustration, rage, and helplessness, is crucial. Emphasis also has been placed on the patient's desires for revenge against self and object, and the manner in which these may be understood and eventually resolved. Only when patient and therapist begin to investigate the adaptive functions of extreme negativity can this pathological symptom be resolved and the patient's awareness of self and sense of autonomy be enhanced. PMID:1763149

  17. 17 CFR 41.47 - Withdrawal of margin.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... after such withdrawal is sufficient to satisfy the required margin for the security futures and related... PRODUCTS Customer Accounts and Margin Requirements § 41.47 Withdrawal of margin. (a) By the...

  18. Comparing Science Achievement Constructs: Targeted and Achieved

    ERIC Educational Resources Information Center

    Ferrara, Steve; Duncan, Teresa

    2011-01-01

    This article illustrates how test specifications based solely on academic content standards, without attention to other cognitive skills and item response demands, can fall short of their targeted constructs. First, the authors inductively describe the science achievement construct represented by a statewide sixth-grade science proficiency test.…

  19. Varieties of Achievement Motivation.

    ERIC Educational Resources Information Center

    Kukla, Andre; Scher, Hal

    1986-01-01

    A recent article by Nicholls on achievement motivation is criticized on three points: (1) definitions of achievement motives are ambiguous; (2) behavioral consequences predicted do not follow from explicit theoretical assumptions; and (3) Nicholls's account of the relation between his theory and other achievement theories is factually incorrect.…

  20. Motivation and School Achievement.

    ERIC Educational Resources Information Center

    Maehr, Martin L.; Archer, Jennifer

    Addressing the question, "What can be done to promote school achievement?", this paper summarizes the literature on motivation relating to classroom achievement and school effectiveness. Particular attention is given to how values, ideology, and various cultural patterns impinge on classroom performance and serve to enhance motivation to achieve.…

  1. PASS and Reading Achievement.

    ERIC Educational Resources Information Center

    Kirby, John R.

    Two studies examined the effectiveness of the PASS (Planning, Attention, Simultaneous, and Successive cognitive processes) theory of intelligence in predicting reading achievement scores of normally achieving children and distinguishing children with reading disabilities from normally achieving children. The first study dealt with predicting…

  2. The Evolution of Negation.

    ERIC Educational Resources Information Center

    Croft, William

    1991-01-01

    Discusses a method for extrapolation of diachronic processes from synchronic states, the dynamicization of synchronic typologies, to propose a hitherto unobserved historical source for markers of verbal negation, namely irregular negative existential predicate forms. Explanations are proposed for the occurrence of the attested processes in this…

  3. Learning from Negative Morality.

    ERIC Educational Resources Information Center

    Oser, Fritz K.

    1996-01-01

    Identifies and discusses the elements and applications of learning from negative morality. Negative morality refers to the experience of learning from mistakes thereby creating a body of personal knowledge about "what not to do." This knowledge not only protects individuals but steers them to the right behavior. (MJP)

  4. On Negative Mass

    NASA Astrophysics Data System (ADS)

    Belletête, Jonathan; Paranjape, M. B.

    2013-06-01

    The Schwarzschild solution to the matter free, spherically symmetric Einstein equations has one free parameter, the mass. But the mass can be of any sign. What is the meaning of the negative mass solutions? The answer to this question for the case of a pure Schwarzschild negative mass black solution is still elusive, however, in this essay, we will consider negative mass solutions within a Schwarzschild-de Sitter geometry. We show that there exist reasonable configurations of matter, bubbles of distributions of matter, that satisfy the dominant energy condition everywhere, that are nonsingular and well behaved everywhere, but correspond to the negative mass Schwarzschild-de Sitter geometry outside the matter distribution. These negative mass bubbles could occur as the end state of a quantum tunneling transition.

  5. The geodynamics of the Levant margin

    NASA Astrophysics Data System (ADS)

    Ben-Avraham, Z.

    2006-12-01

    The Levant continental margin, offshore Israel, Lebanon and Syria, is usually defined as a passive margin that was formed through rifting processes. During the formation two major continental fragments are assumed to separate from the northern edge of the Afro-Arabian plate to form the Levant basin: the Tauride and Eratosthenes blocks. Today an oceanic crust and, in places, a very thin continental crust are present between the Levant margin and Eratosthenes seamount. The margin can be divided into two distinct provinces that are separated by the Carmel Structure, which extends from seawards to the northwest across the continental shelf and slope. The preservation of segmentation, both in the shallow and in the deep structure, insinuates that the two segments were formed through different continental breakup processes, which continue to dictate the style of sediment accumulation. The nature and development of the continental margin offshore Israel were the subject of numerous studies, which suggest that the southern Levant segment (south of the Carmel Structure) was formed through continental rifting processes. In contrast, the northern segment, from the Carmel structure northwards and offshore southern Lebanon, was hardly studied before. Recent studies however indicate that the northern segment shows a strong similarity to classical transform margins in the world. In view of the new classification of the northern Levant margin a modified scenario is suggested for: (a) the initial stages in which the Levant margin was formed; and (b) the present day structural differences between the two segments of the margin. At present, the northern Levant continental margin is being reactivated by transpressional faulting of the marine continuation of the Carmel fault which bends northward at the base of the continental slope due to the rheological discontinuity in this region. This fault system coincides with the sharp continental-oceanic crustal transition, and acts as an

  6. Adrenocortical Carcinoma: Impact of Surgical Margin Status on Long-Term Outcomes

    PubMed Central

    Margonis, Georgios Antonios; Kim, Yuhree; Prescott, Jason D.; Tran, Thuy B.; Postlewait, Lauren M.; Maithel, Shishir K.; Wang, Tracy S.; Evans, Douglas B.; Hatzaras, Ioannis; Shenoy, Rivfka; Phay, John E.; Keplinger, Kara; Fields, Ryan C.; Jin, Linda X.; Weber, Sharon M.; Salem, Ahmed; Sicklick, Jason K.; Gad, Shady; Yopp, Adam C.; Mansour, John C.; Duh, Quan-Yang; Seiser, Natalie; Solorzano, Carmen C.; Kiernan, Colleen M.; Votanopoulos, Konstantinos I.; Levine, Edward A.; Poultsides, George A.; Pawlik, Timothy M.

    2016-01-01

    Background The influence of surgical margin status on long-term outcomes of patients undergoing adrenal resection for ACC remains not well defined. We studied the impact of surgical tumor margin status on recurrence-free survival (RFS) and overall survival (OS) of patients undergoing resection for ACC. Methods A total of 165 patients who underwent adrenal resection for ACC and met inclusion criteria were identified form a multi-institutional database. Clinicopathological data, pathologic margin status, and long-term outcomes were assessed. Patients were stratified into two groups based on margin status: R0 (margin >1 mm) versus R1. Results R0 resection was achieved in 126 patients (76.4 %), whereas 39 patients (23.6 %) had an R1 resection. Median and 5-year OS for patients undergoing R0 resection were 96.3 months and 64.8 % versus 25.1 months and 33.8 % for patients undergoing an R1 resection (both p < 0.001). On multivariable analysis, surgical margin status was an independent predictor of worse OS (hazard ratio [HR] 2.22, 95 % confidence interval [CI] 1.03–4.77; p = 0.04). The incidence of recurrence also differed between the two groups; 5-year RFS was 30.3 % among patients with an R0 resection versus 13.8 % among patients who had an R1 resection (p = 0.03). Lymph node metastasis (N1) was an independent predictor of RFS (HR 2.70, 95 % CI 1.04–6.99; p = 0.04). Conclusions A positive margin after ACC resection was associated with worse long-term survival. Patient selection and an emphasis on surgical technique to achieve R0 margins are pivotal to optimizing the best chance for long-term outcome among patients with ACC. PMID:26286195

  7. Effect of two prophylaxis methods on marginal gap of Cl Vresin-modified glass-ionomer restorations

    PubMed Central

    Kimyai, Soodabeh; Pournaghi-Azar, Fatemeh; Daneshpooy, Mehdi; Abed Kahnamoii, Mehdi; Davoodi, Farnaz

    2016-01-01

    Background. This study evaluated the effect of two prophylaxis techniques on the marginal gap of CI V resin-modified glass-ionomer restorations. Methods. Standard Cl V cavities were prepared on the buccal surfaces of 48 sound bovine mandibular incisors in this in vitro study. After restoration of the cavities with GC Fuji II LC resin-modified glass-ionomer, the samples were randomly assigned to 3 groups of 16. In group 1, the prophylactic procedures were carried out with rubber cup and pumice powder and in group 2 with air-powder polishing device (APD). In group 3 (control), the samples did not undergo any prophylactic procedures. Then the marginal gaps were measured. Two-way ANOVA was used to compare marginal gaps at the occlusal and gingival margins between the groups. Post hoc Tukey test was used for two-by-two comparisons. Statistical significance was set at P < 0.05. Results. There were significant differences in the means of marginal gaps in terms of prophylactic techniques (P < 0.001), with significantly larger marginal gaps in the APD group compared to the pumice and rubber cup group, which in turn exhibited significantly larger marginal gaps compared to the control group (P < 0.0005). In addition, the means of marginal gaps were significant in terms of the margin type (P < 0.001), with significantly larger gaps at gingival margins compared to the occlusal margins (P < 0.0005). Conclusion. The prophylactic techniques used in this study had a negative effect on the marginal gaps of Cl V resin-modified glass-ionomer restorations. PMID:27092211

  8. Effect of two prophylaxis methods on marginal gap of Cl Vresin-modified glass-ionomer restorations.

    PubMed

    Kimyai, Soodabeh; Pournaghi-Azar, Fatemeh; Daneshpooy, Mehdi; Abed Kahnamoii, Mehdi; Davoodi, Farnaz

    2016-01-01

    Background. This study evaluated the effect of two prophylaxis techniques on the marginal gap of CI V resin-modified glass-ionomer restorations. Methods. Standard Cl V cavities were prepared on the buccal surfaces of 48 sound bovine mandibular incisors in this in vitro study. After restoration of the cavities with GC Fuji II LC resin-modified glass-ionomer, the samples were randomly assigned to 3 groups of 16. In group 1, the prophylactic procedures were carried out with rubber cup and pumice powder and in group 2 with air-powder polishing device (APD). In group 3 (control), the samples did not undergo any prophylactic procedures. Then the marginal gaps were measured. Two-way ANOVA was used to compare marginal gaps at the occlusal and gingival margins between the groups. Post hoc Tukey test was used for two-by-two comparisons. Statistical significance was set at P < 0.05. Results. There were significant differences in the means of marginal gaps in terms of prophylactic techniques (P < 0.001), with significantly larger marginal gaps in the APD group compared to the pumice and rubber cup group, which in turn exhibited significantly larger marginal gaps compared to the control group (P < 0.0005). In addition, the means of marginal gaps were significant in terms of the margin type (P < 0.001), with significantly larger gaps at gingival margins compared to the occlusal margins (P < 0.0005). Conclusion. The prophylactic techniques used in this study had a negative effect on the marginal gaps of Cl V resin-modified glass-ionomer restorations. PMID:27092211

  9. Probabilistic objective functions for margin-less IMRT planning

    NASA Astrophysics Data System (ADS)

    Bohoslavsky, Román; Witte, Marnix G.; Janssen, Tomas M.; van Herk, Marcel

    2013-06-01

    We present a method to implement probabilistic treatment planning of intensity-modulated radiation therapy using custom software plugins in a commercial treatment planning system. Our method avoids the definition of safety-margins by directly including the effect of geometrical uncertainties during optimization when objective functions are evaluated. Because the shape of the resulting dose distribution implicitly defines the robustness of the plan, the optimizer has much more flexibility than with a margin-based approach. We expect that this added flexibility helps to automatically strike a better balance between target coverage and dose reduction for surrounding healthy tissue, especially for cases where the planning target volume overlaps organs at risk. Prostate cancer treatment planning was chosen to develop our method, including a novel technique to include rotational uncertainties. Based on population statistics, translations and rotations are simulated independently following a marker-based IGRT correction strategy. The effects of random and systematic errors are incorporated by first blurring and then shifting the dose distribution with respect to the clinical target volume. For simplicity and efficiency, dose-shift invariance and a rigid-body approximation are assumed. Three prostate cases were replanned using our probabilistic objective functions. To compare clinical and probabilistic plans, an evaluation tool was used that explicitly incorporates geometric uncertainties using Monte-Carlo methods. The new plans achieved similar or better dose distributions than the original clinical plans in terms of expected target coverage and rectum wall sparing. Plan optimization times were only about a factor of two higher than in the original clinical system. In conclusion, we have developed a practical planning tool that enables margin-less probability-based treatment planning with acceptable planning times, achieving the first system that is feasible for clinical

  10. Marginal Hepatectomy in the Rat

    PubMed Central

    Madrahimov, Nodir; Dirsch, Olaf; Broelsch, Christoph; Dahmen, Uta

    2006-01-01

    Objective: Based on the 3-dimensional visualization of vascular supply and drainage, a vessel-oriented resection technique was optimized. The new surgical technique was used to determine the maximal reduction in liver mass enabling a 50% 1-week survival rate. Background Data: Determination of the minimal liver mass is necessary in clinical as well as in experimental liver surgery. In rats, survival seems to depend on the surgical technique applied. Extended hepatectomy with removal of 90% of the liver mass was long regarded as a lethal model. Introduction of a vessel-oriented approach enabled long-term survival in this model. Methods: The lobar and vascular anatomy of rat livers was visualized by plastination of the whole organ, respectively, by corrosion casts of the portal vein, hepatic artery and liver veins. The three-dimensional models were used to extract the underlying anatomic structure. In 90% partial hepatectomy, the liver parenchyma was clamped close to the base of the respective liver lobes (left lateral, median and right, liver lobe). Piercing sutures were placed through the liver parenchyma, so that the stem of portal vein and the accompanying hepatic artery but also the hepatic vein were included. Results: A 1-week survival rate of 100% was achieved after 90% hepatectomy. Extending the procedure to 95% resection by additional removal of the upper caudate lobe led to a 1-week survival rate of 66%; 97% partial hepatectomy, accomplished by additional resection of the lower caudate lobe only leaving the paracaval parts of the liver behind, resulted in 100% lethality within 4 days. Conclusions: Using a anatomically based, vessel-oriented, parenchyma-preserving surgical technique in 95% liver resections led to long-term survival. This represents the maximal reduction of liver mass compatible with survival. PMID:16794393

  11. The Achievement Impacts of Arkansas Open-Enrollment Charter Schools

    ERIC Educational Resources Information Center

    Mills, Jonathan N.

    2013-01-01

    This article examines the impacts of Arkansas charter schools on the academic achievement of participating students. Our findings are that charter schools have small but statistically significant, negative impacts on student achievements for both math and literacy. Such negative effects, however, tend to decline with the number of years of charter…

  12. The impact of use of an intraoperative margin assessment device on re-excision rates.

    PubMed

    Sebastian, Molly; Akbari, Stephanie; Anglin, Beth; Lin, Erin H; Police, Alice M

    2015-01-01

    Historically there has been a high rate of surgical interventions to obtain clear margins for breast cancer patients undergoing breast conserving local therapy. An intraoperative margin assessment tool (MarginProbe) has been approved for use in the US since 2013. This study is the first compilation of data from routine use of the device, to assess the impact of device utilization on re-excision rates. We present a retrospective, observational, review from groups of consecutive patients, before and after the implementation of intraoperative use of the device during lumpectomy procedures. Lesions were localized by standard methods. The intraoperative margin assessment device was used on all circumferential margins of the main specimen, but not on any additional shavings. A positive reading by the device led to an additional shaving of the corresponding cavity location. Specimens were also, when feasible, imaged intra-operatively by X-ray, and additional shavings were taken if needed based on clinical assessment. For each surgeon, historical re-excision rates were established based on a consecutive set of patients from a time period proximal to initiation of use of the device. From March 2013 to April 2014 the device was routinely used by 4 surgeons in 3 centers. In total, 165 cases lumpectomy cases were performed. Positive margins resulted in additional re-excision procedures in 9.7% (16/165) of the cases. The corresponding historical set from 2012 and 2013 consisted of 186 Lumpectomy cases, in which additional re-excision procedures were performed in 25.8% (48/186) of the cases. The reduction in the rate of re-excision procedures was significant 62% (P < 0.0001). Use of an intraoperative margin assessment device contributes to achieving clear margins and reducing re-excision procedures. As in some cases positive margins were found on shavings, future studies of interest may include an analysis of the effect of using the device on the shavings intra

  13. Negative refraction using Raman transitions and chirality

    SciTech Connect

    Sikes, D. E.; Yavuz, D. D.

    2011-11-15

    We present a scheme that achieves negative refraction with low absorption in far-off resonant atomic systems. The scheme utilizes Raman resonances and does not require the simultaneous presence of an electric-dipole transition and a magnetic-dipole transition near the same wavelength. We show that two interfering Raman tran-sitions coupled to a magnetic-dipole transition can achieve a negative index of refraction with low absorption through magnetoelectric cross-coupling. We confirm the validity of the analytical results with exact numerical simulations of the density matrix. We also discuss possible experimental implementations of the scheme in rare-earth metal atomic systems.

  14. Negative refraction using Raman transitions and chirality

    NASA Astrophysics Data System (ADS)

    Sikes, D. E.; Yavuz, D. D.

    2011-11-01

    We present a scheme that achieves negative refraction with low absorption in far-off resonant atomic systems. The scheme utilizes Raman resonances and does not require the simultaneous presence of an electric-dipole transition and a magnetic-dipole transition near the same wavelength. We show that two interfering Raman tran-sitions coupled to a magnetic-dipole transition can achieve a negative index of refraction with low absorption through magnetoelectric cross-coupling. We confirm the validity of the analytical results with exact numerical simulations of the density matrix. We also discuss possible experimental implementations of the scheme in rare-earth metal atomic systems.

  15. Predicting Rifted Continental Margin Subsidence History From Satellite Gravity Derived Crustal Thinning: Application to North Atlantic Margins

    NASA Astrophysics Data System (ADS)

    Hurst, N. W.; Kusznir, N. J.; Roberts, A. M.; White, R. S.

    2004-05-01

    3D spectral inversion of satellite derived gravity anomaly data (Smith and Sandwell 1997) and bathymetry data (Gebco 2003) has been used to determine oceanic and continental margin crustal thickness for the North Atlantic between 50 and 70 degrees N. The inverse technique incorporates a correction for the large negative thermal gravity anomaly present in the oceanic and stretched continental lithosphere. This correction can be determined using ocean isochron data for oceanic lithosphere, and margin rift age and beta stretching estimates derived iteratively from crustal basement thickness determined from the gravity inversion for the stretched continental lithosphere. A correction for the gravity anomaly contribution from sediments may be determined using thickness estimates derived from seismic reflection MCS data. Density depth variation within sediments is predicted assuming compaction. Crustal thicknesses determined using a thermal gravity correction derived from ocean isochron data give crustal thicknesses that are consistent with seismic observations. The resulting basement thickness determined from gravity inversion for the thinned continental margin lithosphere may be used to produce estimates of crustal thinning and stretching. Flexural backstripping and reverse post-breakup thermal subsidence modelling may be used to restore present 2D (or 3D) stratigraphic cross sections to earlier post-breakup times. Thermal subsidence arises from the cooling of stretched continental lithosphere and the recently formed oceanic lithosphere, and may be predicted from beta stretching factor (McKenzie 1978) and rift age. Beta stretching factors derived from gravity anomaly inversion have been used to predict reverse thermal subsidence for N Atlantic rifted margins. The resulting palaeo-bathymetric restorations show emergence of the Hatton Bank and NE Faroes rifted margins in early post-breakup times. The predicted palaeo-bathymetries are consistent with palaeo

  16. Dynamically variable negative stiffness structures

    PubMed Central

    Churchill, Christopher B.; Shahan, David W.; Smith, Sloan P.; Keefe, Andrew C.; McKnight, Geoffrey P.

    2016-01-01

    Variable stiffness structures that enable a wide range of efficient load-bearing and dexterous activity are ubiquitous in mammalian musculoskeletal systems but are rare in engineered systems because of their complexity, power, and cost. We present a new negative stiffness–based load-bearing structure with dynamically tunable stiffness. Negative stiffness, traditionally used to achieve novel response from passive structures, is a powerful tool to achieve dynamic stiffness changes when configured with an active component. Using relatively simple hardware and low-power, low-frequency actuation, we show an assembly capable of fast (<10 ms) and useful (>100×) dynamic stiffness control. This approach mitigates limitations of conventional tunable stiffness structures that exhibit either small (<30%) stiffness change, high friction, poor load/torque transmission at low stiffness, or high power active control at the frequencies of interest. We experimentally demonstrate actively tunable vibration isolation and stiffness tuning independent of supported loads, enhancing applications such as humanoid robotic limbs and lightweight adaptive vibration isolators. PMID:26989771

  17. Dynamically variable negative stiffness structures.

    PubMed

    Churchill, Christopher B; Shahan, David W; Smith, Sloan P; Keefe, Andrew C; McKnight, Geoffrey P

    2016-02-01

    Variable stiffness structures that enable a wide range of efficient load-bearing and dexterous activity are ubiquitous in mammalian musculoskeletal systems but are rare in engineered systems because of their complexity, power, and cost. We present a new negative stiffness-based load-bearing structure with dynamically tunable stiffness. Negative stiffness, traditionally used to achieve novel response from passive structures, is a powerful tool to achieve dynamic stiffness changes when configured with an active component. Using relatively simple hardware and low-power, low-frequency actuation, we show an assembly capable of fast (<10 ms) and useful (>100×) dynamic stiffness control. This approach mitigates limitations of conventional tunable stiffness structures that exhibit either small (<30%) stiffness change, high friction, poor load/torque transmission at low stiffness, or high power active control at the frequencies of interest. We experimentally demonstrate actively tunable vibration isolation and stiffness tuning independent of supported loads, enhancing applications such as humanoid robotic limbs and lightweight adaptive vibration isolators. PMID:26989771

  18. Kriging without negative weights

    SciTech Connect

    Szidarovszky, F.; Baafi, E.Y.; Kim, Y.C.

    1987-08-01

    Under a constant drift, the linear kriging estimator is considered as a weighted average of n available sample values. Kriging weights are determined such that the estimator is unbiased and optimal. To meet these requirements, negative kriging weights are sometimes found. Use of negative weights can produce negative block grades, which makes no practical sense. In some applications, all kriging weights may be required to be nonnegative. In this paper, a derivation of a set of nonlinear equations with the nonnegative constraint is presented. A numerical algorithm also is developed for the solution of the new set of kriging equations.

  19. Negative birefringent polyimide films

    NASA Technical Reports Server (NTRS)

    Harris, Frank W. (Inventor); Cheng, Stephen Z. D. (Inventor)

    1994-01-01

    A negative birefringent film, useful in liquid crystal displays, and a method for controlling the negative birefringence of a polyimide film is disclosed which allows the matching of an application to a targeted amount of birefringence by controlling the degree of in-plane orientation of the polyimide by the selection of functional groups within both the diamine and dianhydride segments of the polyimide which affect the polyimide backbone chain rigidity, linearity, and symmetry. The higher the rigidity, linearity and symmetry of the polyimide backbone, the larger the value of the negative birefringence of the polyimide film.

  20. Collapse of modern carbonate platform margins

    SciTech Connect

    Mullins, H.T.; Hine, A.C.; Gardulski, A.

    1985-01-01

    Modern carbonate platform margins in the Florida-Bahama region have been viewed as depositional or constructional features. However, recent studies have shown that carbonate escarpments, such as the Blake-Bahama and West Florida Escarpments, are erosional in origin where the platform margins have a scalloped or horse-shoe shape. Seismic reflection data from one of these crescentic features along the west Florida platform margin indicate that it originated by large scale gravity collapse (slump). This collapse structure extends for at least 120 km along the margin and has removed about 350 m of strata as young as early Neogene. Although at least three generations of slope failure are recognized, catastrophic collapse appears to have occurred in the mid-Miocene. Gravitational instability due to high rates of sediment accumulation may have been the triggering mechanism. These data suggest that submarine slumping is an important process in the retreat of limestone escarpments and in the generation of carbonate megabreccia debris flows. Scalloped platform margins occur on satellite images of northern Exuma Sound and Columbus Basin in the Bahamas. The authors suggest that large-scale submarine slumping can cause elongation of structurally controlled intraplatform basins (Exuma South), and produce anomalous horse-shoe shaped basins (Columbus Basin) by mega-collapse processes.

  1. Ferritin associates with marginal band microtubules

    SciTech Connect

    Infante, Anthony A.; Infante, Dzintra; Chan, M.-C.; How, P.-C.; Kutschera, Waltraud; Linhartova, Irena; Muellner, Ernst W.; Wiche, Gerhard; Propst, Friedrich . E-mail: friedrich.propst@univie.ac.at

    2007-05-01

    We characterized chicken erythrocyte and human platelet ferritin by biochemical studies and immunofluorescence. Erythrocyte ferritin was found to be a homopolymer of H-ferritin subunits, resistant to proteinase K digestion, heat stable, and contained iron. In mature chicken erythrocytes and human platelets, ferritin was localized at the marginal band, a ring-shaped peripheral microtubule bundle, and displayed properties of bona fide microtubule-associated proteins such as tau. Red blood cell ferritin association with the marginal band was confirmed by temperature-induced disassembly-reassembly of microtubules. During erythrocyte differentiation, ferritin co-localized with coalescing microtubules during marginal band formation. In addition, ferritin was found in the nuclei of mature erythrocytes, but was not detectable in those of bone marrow erythrocyte precursors. These results suggest that ferritin has a function in marginal band formation and possibly in protection of the marginal band from damaging effects of reactive oxygen species by sequestering iron in the mature erythrocyte. Moreover, our data suggest that ferritin and syncolin, a previously identified erythrocyte microtubule-associated protein, are identical. Nuclear ferritin might contribute to transcriptional silencing or, alternatively, constitute a ferritin reservoir.

  2. Theory of margination in confined multicomponent suspensions

    NASA Astrophysics Data System (ADS)

    Henriquez Rivera, Rafael; Sinha, Kushal; Graham, Michael

    2015-11-01

    In blood flow, leukocytes and platelets tend to segregate near the vessel walls; this is known as margination. Margination of leukocytes and platelets is important in physiological processes, medical diagnostics and drug delivery. A mechanistic theory is developed to describe flow-induced segregation in confined multicomponent suspensions of deformable particles such as blood. The theory captures the essential features of margination by describing it in terms of two key competing processes in these systems at low Reynolds number: wall-induced migration and hydrodynamic pair collisions. The theory also includes the effect of physical properties of the deformable particles and molecular diffusion. Several regimes of segregation are identified, depending on the value of a ``margination parameter'' M. Moreover, there is a critical value of M below which a sharp ``drainage transition'' occurs: one component is completely depleted from the bulk flow to the vicinity of the walls. Direct hydrodynamic simulations also display this transition in suspensions where the components differ in size or flexibility. The developed mechanistic theory leads to substantial insight into the origins of margination and will help in guiding development of new technologies involving multicomponent suspensions. This work was supported by NSF grant CBET-1436082.

  3. Sound Absorption of a 2DOF Resonant Liner with Negative Bias Flow

    NASA Technical Reports Server (NTRS)

    Ahuja, K. K.; Cataldi, P.; Gaeta, R. J., Jr.

    2000-01-01

    This report describes an experimental study conducted to determine the effect of negative bias flow on the sound absorption of a two degree-of-freedom liner. The backwall for the liner was designed to act as a double-Helmholtz resonator so as to act as a hard wall at all frequencies except at its resonant frequencies. The effect of bias flow is investigated for a buried septum porosity of 2% and 19.5% for bias flow orifice Mach numbers up to 0.311. The bias flow appears to modify the resistance and reactance of the backwall alone at lower frequencies up to about 2 kHz, with marginal effects at higher frequencies. Absorption coefficients close to unity are achieved for a frequency range of 500 - 4000 Hz for the overall liner for a septum porosity of 2% and orifice Mach number of 0.128. Insertion loss tests performed in a flow duct facility for grazing flow Mach numbers up to 0.2 and septum Mach numbers up to 0.15 showed that negative bias flow can increase insertion loss by as much as 10 dB at frequencies in the range of 500 D 1400 Hz compared to no grazing flow. The effectiveness of the negative bias flow is diminished as the grazing flow velocity is increased.

  4. Centrifugal Compressor Surge Margin Improved With Diffuser Hub Surface Air Injection

    NASA Technical Reports Server (NTRS)

    Skoch, Gary J.

    2002-01-01

    Aerodynamic stability is an important parameter in the design of compressors for aircraft gas turbine engines. Compression system instabilities can cause compressor surge, which may lead to the loss of an aircraft. As a result, engine designers include a margin of safety between the operating line of the engine and the stability limit line of the compressor. The margin of safety is typically referred to as "surge margin." Achieving the highest possible level of surge margin while meeting design point performance objectives is the goal of the compressor designer. However, performance goals often must be compromised in order to achieve adequate levels of surge margin. Techniques to improve surge margin will permit more aggressive compressor designs. Centrifugal compressor surge margin improvement was demonstrated at the NASA Glenn Research Center by injecting air into the vaned diffuser of a 4:1-pressure-ratio centrifugal compressor. Tests were performed using injector nozzles located on the diffuser hub surface of a vane-island diffuser in the vaneless region between the impeller trailing edge and the diffuser-vane leading edge. The nozzle flow path and discharge shape were designed to produce an air stream that remained tangent to the hub surface as it traveled into the diffuser passage. Injector nozzles were located near the leading edge of 23 of the 24 diffuser vanes. One passage did not contain an injector so that instrumentation located in that passage would be preserved. Several orientations of the injected stream relative to the diffuser vane leading edge were tested over a range of injected flow rates. Only steady flow (nonpulsed) air injection was tested. At 100 percent of the design speed, a 15-percent improvement in the baseline surge margin was achieved with a nozzle orientation that produced a jet that was bisected by the diffuser vane leading edge. Other orientations also improved the baseline surge margin. Tests were conducted at speeds below the

  5. Negative electrode composition

    DOEpatents

    Kaun, Thomas D.; Chilenskas, Albert A.

    1982-01-01

    A secondary electrochemical cell and a negative electrode composition for use therewith comprising a positive electrode containing an active material of a chalcogen or a transiton metal chalcogenide, a negative electrode containing a lithium-aluminum alloy and an amount of a ternary alloy sufficient to provide at least about 5 percent overcharge capacity relative to a negative electrode solely of the lithium-aluminum alloy, the ternary alloy comprising lithium, aluminum, and iron or cobalt, and an electrolyte containing lithium ions in contact with both of the positive and the negative electrodes. The ternary alloy is present in the electrode in the range of from about 5 percent to about 50 percent by weight of the electrode composition and may include lithium-aluminum-nickel alloy in combination with either the ternary iron or cobalt alloys. A plurality of series connected cells having overcharge capacity can be equalized on the discharge side without expensive electrical equipment.

  6. Logo and Negative Numbers.

    ERIC Educational Resources Information Center

    Strawn, Candace A.

    1998-01-01

    Describes LOGO's turtle graphics capabilities based on a sixth-grade classroom's activities with negative numbers and Logo programming. A sidebar explains LOGO and offers suggestions to teachers for using LOGO effectively. (LRW)

  7. Atomic negative ions

    SciTech Connect

    Brage, T.

    1991-01-01

    We review some of the recent progress in the studies of alkaline-earth, negative ions. Computations of autodetachment rates, electron affinities and transition wavelengths are discussed and some new and improved results are given.

  8. Atomic negative ions

    SciTech Connect

    Brage, T.

    1991-12-31

    We review some of the recent progress in the studies of alkaline-earth, negative ions. Computations of autodetachment rates, electron affinities and transition wavelengths are discussed and some new and improved results are given.

  9. Interaction of 2-Gy Equivalent Dose and Margin Status in Perioperative High-Dose-Rate Brachytherapy

    SciTech Connect

    Martinez-Monge, Rafael; Cambeiro, Mauricio; Moreno, Marta; Gaztanaga, Miren; San Julian, Mikel; Alcalde, Juan; Jurado, Matias

    2011-03-15

    Purpose: To determine patient, tumor, and treatment factors predictive of local control (LC) in a series of patients treated with either perioperative high-dose-rate brachytherapy (PHDRB) alone (Group 1) or with PHDRB combined with external-beam radiotherapy (EBRT) (Group 2). Patient and Methods: Patients (n = 312) enrolled in several PHDRB prospective Phase I-II studies conducted at the Clinica Universidad de Navarra were analyzed. Treatment with PHDRB alone, mainly because of prior irradiation, was used in 126 patients to total doses of 32 Gy/8 b.i.d. or 40 Gy/10 b.i.d. treatments after R0 or R1 resections. Treatment with PHDRB plus EBRT was used in 186 patients to total doses of 16 Gy/4 b.i.d. or 24 Gy/6 b.i.d. treatments after R0 or R1 resections along with 45 Gy of EBRT with or without concomitant chemotherapy. Results: No dose-margin interaction was observed in Group 1 patients. In Group 2 patients there was a significant interaction between margin status and 2-Gy equivalent (Eq2Gy) dose (p = 0.002): (1) patients with negative margins had 9-year LC of 95.7% at Eq2Gy = 62.9Gy; (2) patients with close margins of >1 mm had 9-year LC of 92.4% at Eq2Gy = 72.2Gy, and (3) patients with positive/close <1-mm margins had 9-year LC of 68.0% at Eq2Gy = 72.2Gy. Conclusions: Two-gray equivalent doses {>=}70 Gy may compensate the effect of close margins {>=}1 mm but do not counterbalance the detrimental effect of unfavorable (positive/close <1 mm) resection margins. No dose-margin interaction is observed in patients treated at lower Eq2Gy doses {<=}50 Gy with PHDRB alone.

  10. Negative affixes in medical English.

    PubMed

    Dzuganova, B

    2006-01-01

    Many medical terms have negative meaning expressed by means of a negative prefix or suffix. The most frequently used negative prefixes are: a-, dis-, in-, non-, and un-. There is only one negative suffix -less (Ref. 15). PMID:17125069

  11. Diminishing Marginal Returns and the Production of Education: An International Analysis

    ERIC Educational Resources Information Center

    Harris, Douglas N.

    2007-01-01

    Diminishing marginal returns (DMR) to school inputs could explain a wide variety of findings in the research literature. One important example is the influential finding by Heyneman and Loxley that school inputs are the 'predominant influence' on achievement in developing nations, where input levels are low, even though the same school inputs have…

  12. Risk Informed Margins Management as part of Risk Informed Safety Margin Characterization

    SciTech Connect

    Curtis Smith

    2014-06-01

    The ability to better characterize and quantify safety margin is important to improved decision making about Light Water Reactor (LWR) design, operation, and plant life extension. A systematic approach to characterization of safety margins and the subsequent margin management options represents a vital input to the licensee and regulatory analysis and decision making that will be involved. In addition, as research and development in the LWR Sustainability (LWRS) Program and other collaborative efforts yield new data, sensors, and improved scientific understanding of physical processes that govern the aging and degradation of plant SSCs needs and opportunities to better optimize plant safety and performance will become known. To support decision making related to economics, readability, and safety, the Risk Informed Safety Margin Characterization (RISMC) Pathway provides methods and tools that enable mitigation options known as risk informed margins management (RIMM) strategies.

  13. Raising the Achievement of Low-Performing Students. Policy Brief.

    ERIC Educational Resources Information Center

    Goodwin, Bryan

    This brief synthesizes seven papers commissioned for a series of meetings convened by Mid-Continent Research for Education and Learning to discuss raising the achievement of low-performing students. The purpose of the brief is to identify some causes of the low performance of marginalized students, and then offer research-based solutions for what…

  14. School Counselors: Closing Achievement Gaps and Writing Results Reports

    ERIC Educational Resources Information Center

    Hartline, Julie; Cobia, Debra

    2012-01-01

    Charged with closing the achievement gap for marginalized students, school counselors need to be able to identify gaps, develop interventions, evaluate effectiveness, and share results. This study examined 100 summary results reports submitted by school counselors after having received four days of training on the ASCA National Model. Findings…

  15. [Evaluation of safe resection margins in rectal carcinoma].

    PubMed

    Hovorková, E; Hadži-Nikolov, D; Ferko, A; Örhalmi, J; Chobola, M; Ryška, A

    2014-02-01

    The fact that surgically well performed total mesorectal excision with negative circumferential resection margin represents one of the most important prognostic factors in colorectal carcinoma is already well known. These parameters significantly affect the incidence of local tumour recurrence as well as distant metastasis, and are thus related to the duration of patient survival. The surgeons task is to perform mesorectal excision as completely as possible, i.e., to remove the rectum with an intact cylinder of mesorectal fat. The approach of the pathologist to evaluation of total mesorectal excision specimens differs greatly from that of resection specimens from other parts of the large bowel. Besides evaluation of the usual parameters for colon cancer staging, it is essential to assess certain additional factors specific to rectal carcinomas, namely tumour distance from circumferential (radial) resection margins and the quality of the mesorectal excision. In order to accurately evaluate these parameters, knowledge of a wide range of clinical data is indispensable (results of preoperative imaging, intraoperative findings). For objective evaluation of these parameters it is necessary to introduce standardized procedures for resection specimen processing and macro and microscopic examination. This approach is based mainly on standardized macroscopic photo-documentation of the integrity of the mesorectal surface. Parallel transverse sections of the resection specimens are made with targeted tissue sampling for histological examination. It is essential to have close cooperation between surgeons and pathologists within a multidisciplinary team enabling mutual feedback. PMID:24702293

  16. Marginal deformations of nonrelativistic field theories

    NASA Astrophysics Data System (ADS)

    Mallayev, Davron; Vázquez-Poritz, Justin F.; Zhang, Zhibai

    2014-11-01

    We construct the supergravity duals of marginal deformations of a (0, 2) Landau-Ginsburg theory that describes the supersymmetric lowest Landau level. These deformations preserve supersymmetry and it is proposed that they are associated with the introduction of a phase in the (0, 2) superpotential. We also consider marginal deformations of various field theories that exhibit Schrödinger symmetry and Lifshitz scaling. This includes countably infinite examples with dynamical exponent z =2 based on the Sasaki-Einstein spaces Yp ,q and Lp ,q ,r, as well as an example with general dynamical exponent z ≥1 .

  17. Algorithms for computing the multivariable stability margin

    NASA Technical Reports Server (NTRS)

    Tekawy, Jonathan A.; Safonov, Michael G.; Chiang, Richard Y.

    1989-01-01

    Stability margin for multiloop flight control systems has become a critical issue, especially in highly maneuverable aircraft designs where there are inherent strong cross-couplings between the various feedback control loops. To cope with this issue, we have developed computer algorithms based on non-differentiable optimization theory. These algorithms have been developed for computing the Multivariable Stability Margin (MSM). The MSM of a dynamical system is the size of the smallest structured perturbation in component dynamics that will destabilize the system. These algorithms have been coded and appear to be reliable. As illustrated by examples, they provide the basis for evaluating the robustness and performance of flight control systems.

  18. 17 CFR 242.405 - Withdrawal of margin.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... account after such withdrawal is sufficient to satisfy the required margin for the security futures and...) REGULATIONS M, SHO, ATS, AC, AND NMS AND CUSTOMER MARGIN REQUIREMENTS FOR SECURITY FUTURES Customer Margin Requirements for Security Futures § 242.405 Withdrawal of margin. (a) By the customer. Except as...

  19. 17 CFR 41.47 - Withdrawal of margin.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 17 Commodity and Securities Exchanges 1 2011-04-01 2011-04-01 false Withdrawal of margin. 41.47... PRODUCTS Customer Accounts and Margin Requirements § 41.47 Withdrawal of margin. (a) By the customer... deposited as margin for positions in an account may be withdrawn, provided that the equity in the...

  20. 17 CFR 242.405 - Withdrawal of margin.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 17 Commodity and Securities Exchanges 3 2011-04-01 2011-04-01 false Withdrawal of margin. 242.405...) REGULATIONS M, SHO, ATS, AC, AND NMS AND CUSTOMER MARGIN REQUIREMENTS FOR SECURITY FUTURES Customer Margin Requirements for Security Futures § 242.405 Withdrawal of margin. (a) By the customer. Except as...

  1. Heritability of Creative Achievement

    ERIC Educational Resources Information Center

    Piffer, Davide; Hur, Yoon-Mi

    2014-01-01

    Although creative achievement is a subject of much attention to lay people, the origin of individual differences in creative accomplishments remain poorly understood. This study examined genetic and environmental influences on creative achievement in an adult sample of 338 twins (mean age = 26.3 years; SD = 6.6 years). Twins completed the Creative…

  2. Confronting the Achievement Gap

    ERIC Educational Resources Information Center

    Gardner, David

    2007-01-01

    This article talks about the large achievement gap between children of color and their white peers. The reasons for the achievement gap are varied. First, many urban minorities come from a background of poverty. One of the detrimental effects of growing up in poverty is receiving inadequate nourishment at a time when bodies and brains are rapidly…

  3. States Address Achievement Gaps.

    ERIC Educational Resources Information Center

    Christie, Kathy

    2002-01-01

    Summarizes 2 state initiatives to address the achievement gap: North Carolina's report by the Advisory Commission on Raising Achievement and Closing Gaps, containing an 11-point strategy, and Kentucky's legislation putting in place 10 specific processes. The North Carolina report is available at www.dpi.state.nc.us.closingthegap; Kentucky's…

  4. Wechsler Individual Achievement Test.

    ERIC Educational Resources Information Center

    Taylor, Ronald L.

    1999-01-01

    This article describes the Wechsler Individual Achievement Test, a comprehensive measure of achievement for individuals in grades K-12. Eight subtests assess mathematics reasoning, spelling, reading comprehension, numerical operations, listening comprehension, oral expression, and written expression. Its administration, standardization,…

  5. Inverting the Achievement Pyramid

    ERIC Educational Resources Information Center

    White-Hood, Marian; Shindel, Melissa

    2006-01-01

    Attempting to invert the pyramid to improve student achievement and increase all students' chances for success is not a new endeavor. For decades, educators have strategized, formed think tanks, and developed school improvement teams to find better ways to improve the achievement of all students. Currently, the No Child Left Behind Act (NCLB) is…

  6. Achievement Test Program.

    ERIC Educational Resources Information Center

    Ohio State Dept. of Education, Columbus. Trade and Industrial Education Service.

    The Ohio Trade and Industrial Education Achievement Test battery is comprised of seven basic achievement tests: Machine Trades, Automotive Mechanics, Basic Electricity, Basic Electronics, Mechanical Drafting, Printing, and Sheet Metal. The tests were developed by subject matter committees and specialists in testing and research. The Ohio Trade and…

  7. General Achievement Trends: Maryland

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  8. General Achievement Trends: Arkansas

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  9. General Achievement Trends: Idaho

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  10. General Achievement Trends: Nebraska

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  11. General Achievement Trends: Colorado

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  12. General Achievement Trends: Iowa

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  13. General Achievement Trends: Hawaii

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  14. General Achievement Trends: Kentucky

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  15. General Achievement Trends: Florida

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  16. General Achievement Trends: Texas

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  17. General Achievement Trends: Oregon

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  18. General Achievement Trends: Virginia

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  19. Honoring Student Achievement

    ERIC Educational Resources Information Center

    Education Digest: Essential Readings Condensed for Quick Review, 2004

    2004-01-01

    Is the concept of "honor roll" obsolete? The honor roll has always been a way for schools to recognize the academic achievement of their students. But does it motivate students? In this article, several elementary school principals share their views about honoring student achievement. Among others, Virginia principal Nancy Moga said that students…

  20. Aiming at Achievement.

    ERIC Educational Resources Information Center

    Martinez, Paul

    The Raising Quality and Achievement Program is a 3-year initiative to support further education (FE) colleges in the United Kingdom in their drive to improve students' achievement and the quality of provision. The program offers the following: (1) quality information and advice; (2) onsite support for individual colleges; (3) help with…

  1. Achieving Perspective Transformation.

    ERIC Educational Resources Information Center

    Nowak, Jens

    Perspective transformation is a consciously achieved state in which the individual's perspective on life is transformed. The new perspective serves as a vantage point for life's actions and interactions, affecting the way life is lived. Three conditions are basic to achieving perspective transformation: (1) "feeling" experience, i.e., getting in…

  2. Achieving Public Schools

    ERIC Educational Resources Information Center

    Abowitz, Kathleen Knight

    2011-01-01

    Public schools are functionally provided through structural arrangements such as government funding, but public schools are achieved in substance, in part, through local governance. In this essay, Kathleen Knight Abowitz explains the bifocal nature of achieving public schools; that is, that schools are both subject to the unitary Public compact of…

  3. General Achievement Trends: Tennessee

    ERIC Educational Resources Information Center

    Center on Education Policy, 2009

    2009-01-01

    This general achievement trends profile includes information that the Center on Education Policy (CEP) and the Human Resources Research Organization (HumRRO) obtained from states from fall 2008 through April 2009. Included herein are: (1) Bullet points summarizing key findings about achievement trends in that state at three performance…

  4. Achievement-Based Resourcing.

    ERIC Educational Resources Information Center

    Fletcher, Mike; And Others

    1992-01-01

    This collection of seven articles examines achievement-based resourcing (ABR), the concept that the funding of educational institutions should be linked to their success in promoting student achievement, with a focus on the application of ABR to postsecondary education in the United Kingdom. The articles include: (1) "Introduction" (Mick…

  5. Geochemical discrimination of siliciclastic sediments from active and passive margin settings

    NASA Astrophysics Data System (ADS)

    Verma, Surendra P.; Armstrong-Altrin, John S.

    2016-03-01

    Discrimination of active and passive margins is important from both academic and economic aspects. This can only be successfully achieved, however, if there are major compositional differences among sediments derived from different continental margins. A worldwide database of active and passive margin settings was established from published major and trace element geochemical data of Neogene to Quaternary siliciclastic sediments. These data were used to evaluate the performance of existing discrimination diagrams, which were shown to work unsatisfactorily with success values of mostly between 0% and 30%. Because these diagrams were not based on a statistically coherent methodology, we proposed two new discriminant functions from linear discriminant analysis of multinormally distributed isometric log-transformed ratios of major and combined major and trace elements. These new diagrams showed very high percent success values of about 87%-97% and 84%-86% for the active and passive margins, respectively, for the original database. Excellent performance of the multidimensional diagrams and related discriminant functions was confirmed from 11 test studies involving Quaternary to Holocene siliciclastic sediments from known tectonic margins. The expected result of an active or passive margin was obtained, with most samples plotting correctly in the respective field.

  6. Estimated limits of IMRT dose escalation using varied planning target volume margins

    NASA Astrophysics Data System (ADS)

    Goulet, Christopher C.; Herman, Michael G.; Hillman, David W.; Davis, Brian J.

    2008-07-01

    To estimate the limits of dose escalation for prostate cancer as a function of planning target volume (PTV) margins, the maximum achievable dose (MAD) was determined through iterative plan optimizations from data sets of 18 patients until the dose constraints for rectum, bladder and PTV could no longer be met. PTV margins of 10, 5 and 3 mm yielded a mean MAD of 83.0 Gy (range, 73.8-108.0 Gy), 113.1 Gy (range, 90.0-151.2 Gy) and 135.9 Gy (range, 102.6-189.0 Gy), respectively. All comparisons of MAD among margin groups were statistically significant (P < 0.001). Comparison of prostate volumes of 30-50 mL (n = 8) with volumes of 51-70 mL (n = 7) and 71-105 mL (n = 3) showed an inverse relationship with MAD. Decreases in PTV margin significantly decreased the PTV overlap of the rectum (P < 0.001 for all margin comparisons). With decreases in the PTV margin and maintenance of identical dose constraints, doses well above those currently prescribed for treatment of localized prostate cancer appear feasible. However, the dose escalation suggested by these findings is a theoretical estimate, and additional dose constraints will likely be necessary to limit toxicity to normal tissue.

  7. On the Evolution of Glaciated Continental Margins

    NASA Astrophysics Data System (ADS)

    Sverre Laberg, Jan; Rydningen, Tom Arne; Safronova, Polina A.; Forwick, Matthias

    2016-04-01

    Glaciated continental margins, continental margins where a grounded ice sheet repeatedly has been at or near the shelf break, are found at both northern and southern high-latitudes. Their evolution are in several aspects different from their low-latitude counterparts where eustatic sea-level variations possess a fundamental control on their evolution and where fluvial systems provide the main sediment input. From studies of the Norwegian - Barents Sea - Svalbard and NE Greenland continental margins we propose the following factors as the main control on the evolution of glaciated continental margins: 1) Pre-glacial relief controlling the accommodation space, 2) Ice sheet glaciology including the location of fast-flowing ice streams where source area morphology exerts a fundamental control, 3) Composition of the glacigenic sediments where the clay content in previous studies have been found to be important, and 4) Sea-level controlled both by eustacy and isostacy. From three case studies, 1) the western Barents Sea, 2) part of the North Norwegian (Troms), and 3) the Mid-Norwegian margin, the influence on these factors for the sea-floor morphology, sedimentary processes of the continental slope - deep sea and continental margin architecture are discussed. The pre-glacial relief of the mid-Norwegian and Troms margins relates to the onset of rifting and plate break-up from the early Cenozoic while for the SW Barents Sea, plate shear was followed by rifting. A wide zone of extended continental crust occurs offshore mid-Norway while this zone is much narrower offshore Troms leading to a more pronounced pre-glacial relief. Regarding sediment delivery and ice sheet glaciology the western Barents Sea exemplifies very high sediment input corresponding to an estimated average erosion of the source area of ~0.4 mm/yr (SW Barents Sea), much of which is related to subglacial erosion of Mesozoic - Cenozoic sedimentary rocks from large paleo-ice streams. The mid-Norwegian margin

  8. A novel framework to classify marginal land for sustainable biomass feedstock production.

    PubMed

    Gopalakrishnan, Gayathri; Cristina Negri, M; Snyder, Seth W

    2011-01-01

    To achieve food and energy security, sustainable bioenergy has become an important goal for many countries. The use of marginal lands to produce energy crops is one strategy for achieving this goal, but what is marginal land? Current definitions generally focus on a single criterion, primarily agroeconomic profitability. Herein, we present a framework that incorporates multiple criteria including profitability of current land use, soil health indicators (erosion, flooding, drainage, or high slopes), and environmental degradation resulting from contamination of surface water or groundwater resources. We tested this framework for classifying marginal land in the state of Nebraska and estimated the potential for using marginal land to produce biofuel crops. Our results indicate that approximately 1.6 million ha, or 4 million acres, of land (approximately 8% of total land area) could be classified as marginal on the basis of at least two criteria. Second-generation lignocellulosic bioenergy crops such as switchgrass ( Panicum virgatum L.), miscanthus (Miscanthus giganteus), native prairie grasses, and short-rotation woody crops could be grown on this land in redesigned landscapes that meet energy and environmental needs, without significant impacts on food or feed production. Calculating tradeoffs between the economics of redesigned landscapes and current practices at the field scale is the next step for determining functional designs for integrating biofuel feedstock production into current land management practices. PMID:21869522

  9. The Negative "Aspects" of Children's Writing.

    ERIC Educational Resources Information Center

    Gale, Irma F.; Boisvert, Louis

    This study of the negative side of children's writing utilized an experimental group and a control group equalized according to sex and the results of the language sub-tests of the Stanford Achievement Tests. Students wrote two 1,000 word composition samples, one during the first month of the study and one during the ninth month. The purposes of…

  10. Association between Emotional Variables and School Achievement

    ERIC Educational Resources Information Center

    Randler, Christoph

    2009-01-01

    Recent psychological studies highlight emotional aspects, and they show an important role within individual learning processes. Hereby, positive emotions were supposed to positively influence learning and achievement processes and negative ones do the contrary. In this study, an educational unit "ecosystem lake" was used during which achievement…

  11. Active Learning Strategies and Vocabulary Achievement

    ERIC Educational Resources Information Center

    Griffith, John R.

    2015-01-01

    Using a quantitative method of data collection, this research explored the question: Do active learning strategies used in grades 5 and 6 affect student vocabulary achievement in a positive or negative direction? In their research, Wolfe (2001), Headley, et al., (1995), Freiberg, et al., (1992), and Brunner (2009) emphasize the importance of…

  12. Advanced patterning approaches based on negative-tone development (NTD) process for further extension of 193nm immersion lithography

    NASA Astrophysics Data System (ADS)

    Shirakawa, Michihiro; Inoue, Naoki; Furutani, Hajime; Yamamoto, Kei; Goto, Akiyoshi; Fujita, Mitsuhiro

    2015-03-01

    Two approaches which achieve the further evolution of NTD (Negative Tone Development) process are shown in this article. One is ACCEL (Advanced Chemical Contrast Enhancement Layer) process that can improve the lithography performance and the other is DTD (Dual Tone Development) process that can shrink patterning pitch below the limit of single exposure process. ACCEL is an additionally provided layer which is coated on a surface of NTD resist film before exposure and removed by NTD developer. ACCEL can enhance the acid distribution and dissolution contrast of the NTD resist. In fact, lithography performances such as exposure latitude (EL) and DOF improved dramatically by applying ACCEL compared to the NTD resist without ACCEL. We consider that suppression of excessive acid diffusion and material transfer between the resist layer and the ACCEL layer are the causes of the contrast enhancement. DTD process is one of the simplest pitch shrink method which is achieved by repeating PTD and NTD process. Feasibility study of DTD patterning has been demonstrated so far. However, Exposure latitude margin and CDU performance were not sufficient for applying DTD to HVM. We developed the novel DTD specific resist under a new concept, and 32 nm half pitch (hp) contact hole (CH) pattern was successfully formed with enough margins. DTD line and space (L/S) patterning are also demonstrated and 24 nm hp L/S pattern can be resolved. k1 factors of DTD CH and L/S patterns reach to 0.20 and 0.15, respectively.

  13. Image Guidance-Based Target Volume Margin Expansion in IMRT of Head and Neck Cancer.

    PubMed

    Srivastava, Shiv P; Cheng, Chee-Wai; Das, Indra J

    2016-02-01

    This study quantifies the setup uncertainties to optimize the planning target volume (PTV) margin based on daily image guidance, its dosimetric impact, and radiobiological implication for intensity-modulated radiation therapy (IMRT) in head and neck cancer. Ten patients were retrospectively chosen who had been treated with IMRT and with daily image-guided radiation therapy (IGRT). The daily setup errors of the 10 patients from on-board imaging for the entire treatment were analyzed. Planning target volumes were generated by expanding the clinical target volumes (CTVs) with 0 to 10 mm margins. The IMRT plans with the same dose-volume constraints were created in an Eclipse treatment planning system. The effect of volume expansion was analyzed with biological indices such as tumor control probability, normal tissue complication probability (NTCP), and equivalent uniform dose. Analysis of 906 daily setup corrections using daily IGRT showed that 98% of the daily setups are within ± 5 mm. The relative increase in PTV-CTV volume from 0 to 10 mm margins provides nearly 4-fold volume increase and is linearly related to monitor unit (MU). The increase in MU is about 5%/mm margin increase. The relative increase in NTCP of parotids from 5 to 10 mm margins is 3.2 ± 1.15. Increase in PTV margin increases extra tissue volume with a corresponding increase in MU for treatment and NTCP values. Even a small margin increase (eg, 1 mm) may result in increase of more than 20% in relative extra volume and 15% in NTCP value of organs at risk (OARs). With image guidance, the setup uncertainty could be achieved within ± 5 mm for 98% of the treatments, and a margin <5 mm for PTV may seem desirable to reduce the extra tissue irradiated, but at the expense of a more demanding setup accuracy. PMID:25432930

  14. Magnetic Resonance Imaging-Defined Treatment Margins in Iodine-125 Prostate Brachytherapy

    SciTech Connect

    Crook, Juanita; Patil, Nikhilesh; Ma, Clement; McLean, Michael; Borg, Jette

    2010-07-15

    Purpose: Low-dose-rate prostate brachytherapy achieves a very high and effective intraprostatic dose. Implant quality parameters concentrate on the dose received by the prostate (D90, V100) but not that received by the periprostatic tissue. We calculated implant quality parameters, D90 and V100, for the magnetic resonance imaging (MRI)-defined prostate plus 2, 3, and 5 mm. Methods and Materials: A total of 131 men with early-stage prostate cancer treated with iodine-125 brachytherapy represent all those treated with brachytherapy monotherapy in our institution in 2005. Postplan assessment was performed at 1 month using magnetic resonance (MR)-computed tomography (CT) fusion. The prostate V100 and D90 were calculated with 2-, 3-, and 5-mm margins. Results were compared with those in 8 patients with biopsy-proven local failure occurring in an experience of more than 1,100 implants. Results: Mean prostate V100 (SD) and D90 (SD) were 95.6% (4.1) and 117.2% (12.7). For prostate plus a 2-mm margin the D90 was 107.9% (14.3) and for a 3-mm margin 96.0 % (14.0). For prostate plus a 5-mm margin, the D90 was only 78.4% (11.0). The 8 patients experiencing local failure, despite adequate implants, had a lower mean V100 of 91.2% (SD, 2.8; p = 0.0008) and D90 of 103.7% (SD, 8.3; p = 0.002) and significantly inferior margin coverage. Conclusions: Satisfactory coverage of a 2-mm and 3-mm periprostatic margin is obtained with the described planning approach. Coverage falls off significantly by 5 mm. The 8 patients who experienced local failure had significantly lower doses than the margin cohort. Although the V100 and D90 would be considered acceptable, the fall-off in margin coverage was observed by 3 mm.

  15. Keeping Academically Marginal Youth in School.

    ERIC Educational Resources Information Center

    Alpert, Geoffrey; Dunham, Roger

    1986-01-01

    From among factors theoretically considered relevant to preventing school dropouts, empirical procedures identified five variables that predicted most of the variance among marginal youth: (1) extent of misbehavior in school; (2) belief in school's relevance to employment; (3) feelings of success in school; (4) parental monitoring of behavior; (5)…

  16. Late quaternary sequence stratigraphy, South Florida margin

    SciTech Connect

    Locker, S.D.; Hine, A.C.

    1995-12-01

    Late Quaternary sea-level change and the Florida Current have combined to produce a progradational shelf-slope margin along the western portion of the south Florida Platform facing the Straits of Florida. Analysis of high resolution seismic reflection profiles suggest at least eight 5th order late Quaternary sequences downlap onto the Pourtales Terrace at 250 m water depth. Along most of the south Florida margin, this Late Quaternary section is very thin, and only where significant accumulations occur can the stratigraphic patterns produced by sea-level change be clearly observed. Recognition of systems tracts and their boundaries from high-resolution seismic data is important for prediction of sedimentary facies and stratigraphic development of margins. Many south Florida seismic boundaries can be fit to the Exxon sequence stratigraphy model. Others appear to reflect the added effect of bottom-current erosion that complicates the signal produced by sea-level change. Overall, the sea-level signal appears to dominate the stratigraphic record, especially from the 2-dimensional perspective of dip-oriented seismic profiles. However, the 3-dimensional geometry of deposits are strongly influenced by along slope accumulation patterns controlled by the Florida Current. This study provides new insight on the importance of both geostrophic boundary currents and sea-level change in controlling stratigraphic development of a carbonate platform margin. Similar anomalously thick slope deposits in ancient sequences may indicate similar controls on accumulation and could lend to predictions of related paleo-platform configurations.

  17. Second Language Learners' Use of Marginal Glosses

    ERIC Educational Resources Information Center

    O'Donnell, Mary E.

    2012-01-01

    The use of marginal reading glosses by 18 second language (L2) learners is examined through a quantitative and qualitative analysis of audiotaped think-aloud protocols. How these readers interact with the glosses is identified and divided into five categories or gloss interactions. Examples from each are presented. The primary research question…

  18. 12 CFR 220.4 - Margin account.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Banking FEDERAL RESERVE SYSTEM (CONTINUED) BOARD OF GOVERNORS OF THE FEDERAL RESERVE SYSTEM CREDIT BY... requirement under this part shall be unavailable to satisfy any other requirement. (d) Liquidation in lieu of... liquidation is required, whichever is less. If the margin deficiency created or increased is $1000 or less,...

  19. 5TH BIOTECHNOLOGICAL INVESTIGATIONS OCEAN MARGINS PROGRAM

    SciTech Connect

    DR. ARTURO MASSOL, PROGRAM CHAIR; DR. ROSA BUXEDA, PROGRAM CO-CHAIR

    2004-01-08

    BI-OMP supports DOE's mission in Climate Change Research. The program provides the fundamental understanding of the linkages between carbon and nitrogen cycles in ocean margins. Researchers are providing a mechanistic understanding of these cycles, using the tools of modern molecular biology. The models that will allow policy makers to determine safe levels of greenhouse gases for the Earth System.

  20. On the marginal stability of upwind schemes

    NASA Astrophysics Data System (ADS)

    Gressier, J.; Moschetta, J.-M.

    Following Quirk's analysis of Roe's scheme, general criteria are derived to predict the odd-even decoupling. This analysis is applied to Roe's scheme, EFM Pullin's scheme, EIM Macrossan's scheme and AUSM Liou's scheme. Strict stability is shown to be desirable to avoid most of these flaws. Finally, the link between marginal stability and accuracy on shear waves is established.

  1. RISK-INFORMED SAFETY MARGIN CHARACTERIZATION

    SciTech Connect

    Nam Dinh; Ronaldo Szilard

    2009-07-01

    The concept of safety margins has served as a fundamental principle in the design and operation of commercial nuclear power plants (NPPs). Defined as the minimum distance between a system’s “loading” and its “capacity”, plant design and operation is predicated on ensuring an adequate safety margin for safety-significant parameters (e.g., fuel cladding temperature, containment pressure, etc.) is provided over the spectrum of anticipated plant operating, transient and accident conditions. To meet the anticipated challenges associated with extending the operational lifetimes of the current fleet of operating NPPs, the United States Department of Energy (USDOE), the Idaho National Laboratory (INL) and the Electric Power Research Institute (EPRI) have developed a collaboration to conduct coordinated research to identify and address the technological challenges and opportunities that likely would affect the safe and economic operation of the existing NPP fleet over the postulated long-term time horizons. In this paper we describe a framework for developing and implementing a Risk-Informed Safety Margin Characterization (RISMC) approach to evaluate and manage changes in plant safety margins over long time horizons.

  2. Young People Speaking Back from the Margins

    ERIC Educational Resources Information Center

    Smyth, John

    2010-01-01

    The diminished educational opportunities and subsequent life chances of many marginalized young people have been dramatic, even to the point of being catastrophic. But they are not hapless victims, nor are they passive recipients of deficit categories like "at riskness", placed upon them by the media, politicians, agencies, and some academics.…

  3. Japan's Winning Margins. Management, Training, and Education.

    ERIC Educational Resources Information Center

    Lorriman, John; Kenjo, Takashi

    This book explains the fundamental reasons for Japan's astonishing commercial success in relation to its Western competitors. Chapter 1 is an introduction. Chapter 2 discusses implications of Japanese history for education, training, and management. Chapter 3 looks at the first winning margin--education. It covers the following: Japan's long…

  4. Confronting the Marginalization of Culturally Responsive Pedagogy

    ERIC Educational Resources Information Center

    Sleeter, Christine E.

    2012-01-01

    Globally, over the last two decades, attention to culturally responsive, multicultural approaches to teaching have largely been supplanted by standardized curricula and pedagogy that derive from neoliberal business models of school reform. In this essay, I discuss three factors that contribute to the marginalization of culturally responsive…

  5. 12 CFR 48.9 - Margin requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ..., in retail forex transactions must collect from each retail forex customer an amount of margin not less than: (1) Two percent of the notional value of the retail forex transaction for major currency pairs and 5 percent of the notional value of the retail forex transaction for all other currency...

  6. 12 CFR 240.9 - Margin requirements

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... required. A banking institution engaging, or offering to engage, in retail forex transactions must collect from each retail forex customer an amount of margin not less than: (1) Two percent of the notional value of the retail forex transaction for major currency pairs and 5 percent of the notional value...

  7. 12 CFR 349.9 - Margin requirements.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... depository institution engaging, or offering to engage, in retail forex transactions must collect from each retail forex customer an amount of margin not less than: (1) Two percent of the notional value of the retail forex transaction for major currency pairs and 5 percent of the notional value of the retail...

  8. 12 CFR 349.9 - Margin requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... depository institution engaging, or offering to engage, in retail forex transactions must collect from each retail forex customer an amount of margin not less than: (1) Two percent of the notional value of the retail forex transaction for major currency pairs and 5 percent of the notional value of the retail...

  9. 12 CFR 48.9 - Margin requirements.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., in retail forex transactions must collect from each retail forex customer an amount of margin not less than: (1) Two percent of the notional value of the retail forex transaction for major currency pairs and 5 percent of the notional value of the retail forex transaction for all other currency...

  10. 12 CFR 349.9 - Margin requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... depository institution engaging, or offering to engage, in retail forex transactions must collect from each retail forex customer an amount of margin not less than: (1) Two percent of the notional value of the retail forex transaction for major currency pairs and 5 percent of the notional value of the retail...

  11. 12 CFR 48.9 - Margin requirements.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ..., in retail forex transactions must collect from each retail forex customer an amount of margin not less than: (1) Two percent of the notional value of the retail forex transaction for major currency pairs and 5 percent of the notional value of the retail forex transaction for all other currency...

  12. Negative pressure wound therapy.

    PubMed

    Thompson, James T; Marks, Malcolm W

    2007-10-01

    Negative pressure wound therapy has become an increasingly important part of wound management. Over the last decade, numerous uses for this method of wound management have been reported, ranging from acute and chronic wounds, to closure of open sternal and abdominal wounds, to assistance with skin grafts. The biophysics behind the success of this treatment largely have focused on increased wound blood flow, increased granulation tissue formation, decreased bacterial counts, and stimulation of wound healing pathways through shear stress mechanisms. The overall success of negative pressure wound therapy has led to a multitude of clinical applications, which are discussed in this article. PMID:17967622

  13. [Achievement of therapeutic objectives].

    PubMed

    Mantilla, Teresa

    2014-07-01

    Therapeutic objectives for patients with atherogenic dyslipidemia are achieved by improving patient compliance and adherence. Clinical practice guidelines address the importance of treatment compliance for achieving objectives. The combination of a fixed dose of pravastatin and fenofibrate increases the adherence by simplifying the drug regimen and reducing the number of daily doses. The good tolerance, the cost of the combination and the possibility of adjusting the administration to the patient's lifestyle helps achieve the objectives for these patients with high cardiovascular risk. PMID:25043543

  14. Evolution of Northeast Atlantic magmatic continental margins

    NASA Astrophysics Data System (ADS)

    England, Richard; Cornwell, David; Ramsden, Alice

    2014-05-01

    One of the major problems interpreting the evolution of magmatic continental margins such as those which dominate the Irish, UK and Norwegian margins of the NE Atlantic is that the structure which should record the pre-magmatic evolution of the rift and which potentially influences the character of the rifting process is partially or completely obscured by thick basalt lava flows and sills. A limited number of deep reflection seismic profiles acquired with tuned seismic sources have penetrated the basalts and provide an image of the pre-magmatic structure, otherwise the principle data are lower resolution wide-angle/refraction profiles and potential field models which have greater uncertainties associated with them. In order to sidestep the imaging contraints we have examined the Ethiopian ñ Afar rift system to try to understand the rifting process. This magmatic rift system provides, along its length, a series of ësnapshotsí into the possible tectonic evolution of a magmatic continental margin which are associated with different amounts of extension. The Main Ethiopian rift contains an embryonic magmatic passive margin dominated by faulting at the margins of the rift and en-echlon magmatic zones at the centre. Further north toward Afar the rift becomes infilled with extensive lava flows fed from fissure systems in the widening rift zone. Deep seismic profiles crossing the NE Atlantic margins reveal ocean dipping reflector sequences (ODRS) of basaltic lavas overlying extended crust and lower crustal sill complexes of intruded igneous rock, often referred to as underplate, which extend back beneath the continental margin. The ODRS show a variety of morphologies and settings but frequently occur in fault bounded rift structures along the margins. We suggest, by analogy to the observations that can be made in the Ethiopia Afar rift that these fault bounded basins largely form at the embryonic rift stage and are then partially or completely filled with lavas fed

  15. Gas hydrates of outer continental margins

    SciTech Connect

    Kvenvolden, K.A. )

    1990-05-01

    Gas hydrates are crystalline substances in which a rigid framework of water molecules traps molecules of gas, mainly methane. Gas-hydrate deposits are common in continental margin sediment in all major oceans at water depths greater than about 300 m. Thirty-three localities with evidence for gas-hydrate occurrence have been described worldwide. The presence of these gas hydrates has been inferred mainly from anomalous lacoustic reflectors seen on marine seismic records. Naturally occurring marine gas hydrates have been sampled and analyzed at about tensites in several regions including continental slope and rise sediment of the eastern Pacific Ocean and the Gulf of Mexico. Except for some Gulf of Mexico gas hydrate occurrences, the analyzed gas hydrates are composed almost exclusively of microbial methane. Evidence for the microbial origin of methane in gas hydrates includes (1) the inverse relation between methane occurence and sulfate concentration in the sediment, (2) the subparallel depth trends in carbon isotopic compositions of methane and bicarbonate in the interstitial water, and (3) the general range of {sup 13}C depletion ({delta}{sub PDB}{sup 13}C = {minus}90 to {minus}60 {per thousand}) in the methane. Analyses of gas hydrates from the Peruvian outer continental margin in particular illustrate this evidence for microbially generated methane. The total amount of methane in gas hydrates of continental margins is not known, but estimates of about 10{sup 16} m{sup 3} seem reasonable. Although this amount of methane is large, it is not yet clear whether methane hydrates of outer continental margins will ever be a significant energy resource; however, these gas hydrates will probably constitute a drilling hazard when outer continental margins are explored in the future.

  16. Convergent Margin Structure and a Unifying Concept

    NASA Astrophysics Data System (ADS)

    von Huene, R.; Ranero, C. R.; Scholl, D. W.

    2008-12-01

    Marine observations of the past decade resolve 3 domains of different mechanics in space that probably respond differently from each other during an earthquake cycle. Accretion is common along thickly (>1 km) sedimented trenches and slowly (<50km/myr) converging margins. Erosion is common where convergence is greater which also reduces trench sediment thickness by rapid subduction. However erosion and accretion can be coeval, for instance, subducted seamounts erode the upper plate as adjacent sediment accretes. Trench sediment abundance appears to be a master control of tectonic erosion or accretion. Subducting plate relief and bending, fluid systems, input plate temperature, and material differences seem less important. From recent observations a unifying framework concept to aid interpretations of both accreting and eroding margins is proposed. Over a long term (Ma) the subduction channel accepts a finite amount of material. The excess amount will accrete and a shortage of trench sediment enhances erosion (Cloos and Shreve, 1988). If conditions remain consistent over ~1 Ma periods, the margin configuration becomes typically accretionary or erosional. In each margin segment the short term inter plate friction and material strength changes during the earthquake cycle as proposed by Wang and Hu, 2006. Mechanics probably changes locally during the cycle as well. K. Wang, Y. Hu, Accretionary prisms in subduction earthquake cycles: the theory of dynamic Coulomb wedge, J. Geophys. Res. 111 (2006) B06410, doi:10.1029/2005JB004094. Cloos, M., and R.L. Shreve, (1988), Subduction channel model of prism accretion, melange formation, sediment subduction, and subduction erosion at convergent plate margins: 2. Implications and discussion, Pageoph, v. 129, n. ¾ 501-545

  17. Predicting Achievement and Motivation.

    ERIC Educational Resources Information Center

    Uguroglu, Margaret; Walberg, Herbert J.

    1986-01-01

    Motivation and nine other factors were measured for 970 students in grades five through eight in a study of factors predicting achievement and predicting motivation. Results are discussed. (Author/MT)

  18. Attractiveness and School Achievement

    ERIC Educational Resources Information Center

    Salvia, John; And Others

    1977-01-01

    The purpose of this study was to ascertain the relationship between rated attractiveness and two measures of school performance. Attractive children received significantly higher report cards and, to some degree, higher achievement test scores than their unattractive peers. (Author)

  19. Student Achievement and Motivation

    ERIC Educational Resources Information Center

    Flammer, Gordon H.; Mecham, Robert C.

    1974-01-01

    Compares the lecture and self-paced methods of instruction on the basis of student motivation and achieveme nt, comparing motivating and demotivating factors in each, and their potential for motivation and achievement. (Authors/JR)

  20. Subsets of Women With Close or Positive Margins After Breast-Conserving Surgery With High Local Recurrence Risk Despite Breast Plus Boost Radiotherapy

    SciTech Connect

    Lupe, Krystine; Truong, Pauline T.; Alexander, Cheryl; Lesperance, Mary; Speers, Caroline; Tyldesley, Scott

    2011-11-15

    Purpose: (1) To examine the effect of surgical margin status on local recurrence (LR) and survival following breast-conserving therapy; (2) To identify subsets with close or positive margins with high LR risk despite whole breast radiotherapy (RT) plus boost. Methods and Materials: Subjects were 2,264 women with pT1-3, any N, M0 invasive breast cancer, treated with breast-conserving surgery and whole breast {+-} boost RT. Five-year Kaplan-Meier (KM) LR, breast cancer-specific and overall survival (BCSS and OS) were compared between cohorts with negative (n = 1,980), close (n = 222), and positive (n = 62) margins. LR rates were analyzed according to clinicopathologic characteristics. Multivariable Cox regression modeling and matched analysis of close/positive margin cases and negative margin controls were performed. Results: Median follow-up was 5.2 years. Boost RT was used in 92% of patients with close or positive margins. Five-year KM LR rates in the negative, close and positive margin cohorts were 1.3%, 4.0%, and 5.2%, respectively (p = 0.001). BCSS and OS were similar in the three margin subgroups. In the close/positive margin cohort, LR rates were 10.2% with age <45 years, 11.8% with Grade III, 11.3% with lymphovascular invasion (LVI), and 26.3% with {>=}4 positive nodes. Corresponding rates in the negative margin cohort were 2.3%, 2.4%, 1.0%, and 2.4%, respectively. On Cox regression analysis of the entire cohort, close or positive margin, Grade III histology, {>=}4 positive nodes, and lack of systemic therapy were significantly associated with higher LR risk. When close/positive margin cases were matched to negative margin controls, the difference in 5-year LR remained significant (4.25% vs. 0.7%, p < 0.001). Conclusions: On univariable analysis, subsets with close or positive margins, in combination with age <45 years, Grade III, LVI, and {>=}4 positive nodes, have 5-year LR >10% despite whole breast plus boost RT. These patients should be considered for

  1. [Negative pressure wound therapy - review].

    PubMed

    Gudmundsdottir, Ingibjorg; Steingrimsson, Steinn; Valsdottir, Elsa; Gudbjartsson, Tomas

    2014-04-01

    Negative pressure wound therapy (NPWT) is a new therapeutic option in wound healing and was first described in its present form in 1997. A vacuum source is used to create sub-atmospheric pressure in the local wound environment to promote healing. This is achieved by connecting a vacuum pump to a tube that is threaded into a wound gauze or foam filler dressing covered with a drape. This concept in wound treatment has been shown to be useful in treating different wound infections, including diabetic wounds as well as complex infections of the abdomen and thorax. NPWT has been used in Iceland for over a decade and its use is steadily increasing. This review describes the indications and outcome of NPWT and is aimed at a broad group of doctors and nurses where recent Icelandic studies on the subject are covered. PMID:24713539

  2. Marginally specified generalized linear mixed models: a robust approach.

    PubMed

    Mills, J E; Field, C A; Dupuis, D J

    2002-12-01

    Longitudinal data modeling is complicated by the necessity to deal appropriately with the correlation between observations made on the same individual. Building on an earlier nonrobust version proposed by Heagerty (1999, Biometrics 55, 688-698), our robust marginally specified generalized linear mixed model (ROBMS-GLMM) provides an effective method for dealing with such data. This model is one of the first to allow both population-averaged and individual-specific inference. As well, it adopts the flexibility and interpretability of generalized linear mixed models for introducing dependence but builds a regression structure for the marginal mean, allowing valid application with time-dependent (exogenous) and time-independent covariates. These new estimators are obtained as solutions of a robustified likelihood equation involving Huber's least favorable distribution and a collection of weights. Huber's least favorable distribution produces estimates that are resistant to certain deviations from the random effects distributional assumptions. Innovative weighting strategies enable the ROBMS-GLMM to perform well when faced with outlying observations both in the response and covariates. We illustrate the methodology with an analysis of a prospective longitudinal study of laryngoscopic endotracheal intubation, a skill that numerous health-care professionals are expected to acquire. The principal goal of our research is to achieve robust inference in longitudinal analyses. PMID:12495126

  3. Seismic margin assessment of evolutionary light water reactors

    SciTech Connect

    Ali, S.A.; Bagchi, G.

    1996-12-01

    The objectives of the US Nuclear Regulatory Commission (NRC) staff`s review of the evolutionary light water reactors (ELWR) probabilistic risk assessment (PRA) are drawn from 10 CFR Part 52, the Commission`s Severe Reactor Accident Policy Statement regarding future designs and existing plants, the Commission`s Safety Goal Policy Statement, The Commission approved positions concerning the analyses of external and events contained in SECY-93-087, and NRC interest in the use of PRA to help improve future reactor designs. In general, these objectives have been achieved by the ELWR PRAs and the NRC staff`s review. The staff`s applicable regulation for the analysis of external events for the ELWR PRAs is as follows. The probabilistic risk assessment required by 10 CFR 52.47(a)(1)(v) must include an assessment of internal and external events. For external events, simplified probabilistic methods and margins methods may be used to assess the capacity of the standard design to withstand the effects of events such as fires and earthquakes. Traditional probabilistic techniques should be used to evaluate internal floods. For earthquakes, a seismic margin analysis must consider the effects of earthquakes with accelerations approximately one and two-thirds the acceleration of the safe-shutdown earthquake (SSE).

  4. When is Transplantation with a "Marginal Kidney" Justifiable?

    PubMed

    Rouchi, Alireza Heidary; Mahdavi-Mazdeh, Mitra

    2016-01-01

    The ability of kidney transplantation to improve quality of life has made this therapeutic modality the treatment of choice among renal replacement therapies; however, the continuing organ shortage has forced the use of marginal kidneys as a supplementary source of allografts. It has been repeatedly suggested that failed kidney transplant recipients have greater morbidity and mortality compared with dialysis patients with no renal transplant history. Achieving an optimal balance between the advantages of kidney transplant and disadvantages of allografts with marginal quality is a topic of controversy in transplant medicine. The major and potentially life-threatening complications of immunosuppressive therapies and shorter lifespan following graft failure necessitate a reappraisal of kidney transplant programs from expanded-criteria deceased donors, which can neither necessarily give dialysis patients a better quality of life nor a significant survival benefit, especially in settings with additional diminished graft survival due to HLA-mismatch. It should be offered just to those with short life expectancy and with HLA-matching. The last item is very important in countries without mandatory HLA-matching protocols for kidney transplantation programs. PMID:27457730

  5. The Negative Repetition Effect

    ERIC Educational Resources Information Center

    Mulligan, Neil W.; Peterson, Daniel J.

    2013-01-01

    A fundamental property of human memory is that repetition enhances memory. Peterson and Mulligan (2012) recently documented a surprising "negative repetition effect," in which participants who studied a list of cue-target pairs twice recalled fewer targets than a group who studied the pairs only once. Words within a pair rhymed, and…

  6. [Chemotherapies of negative schizophrenia].

    PubMed

    Petit, M; Dollfus, S

    1991-01-01

    Five years ago, Goldberg claimed that negative symptoms of schizophrenia do respond to neuroleptics. This apparent discovery is, in fact, a very common way of thinking for European schools of psychiatry, specially the French one guided by Delay and Deniker. Initially focused on reserpine and some alerting phenothiazines such as thioproperazine, this opinion has been extended to benzamides in the 1970s. The analysis of the publications devoted to this point indicates that several drugs are actually considered as potent disinhibitors (i.e. active on negative symptoms of schizophrenia): Phenothiazines: As shown in the controlled studies by Itil (1971), Poirier-Littré (1988), fluphenazine and pipotiazine improve the BPRS anergia factor and the SANS score. Butyrophenones: The first description of the "imipramine like" effect of trifluperidol by Janssen (1959) initiated the studies by Gallant (1960), Fox (1963). They compared trifluperidol at low doses versus haloperidol and chlorpromazine at medium and high doses, BPRS anergia factor improved only at low doses. Diphenylbutylpiperidines (DPBP): Meltzer's review (1986) concluded to the efficacy of such drugs on negative symptoms appearing as a specific biochemical relationship effect. A definite analysis about doses leads to a very different interpretation: DPBP low doses and only low doses improved negative symptoms as much as some low doses of phenothiazines. On the opposite, DPBP, phenothiazines and butyrophenones high doses are inefficient.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:1683624

  7. Raising Achievement through Inclusion

    ERIC Educational Resources Information Center

    Persson, Elisabeth

    2013-01-01

    In 2007, Swedish authorities introduced open publication of comparisons of students' results at the end of compulsory school. In this study, we investigated a municipality that had succeeded in breaking a negative trend from a bottom position in the ranking in 2007 to a top position in 2010, apparently through inclusive practices. The purpose…

  8. Microwave gain medium with negative refractive index

    NASA Astrophysics Data System (ADS)

    Ye, Dexin; Chang, Kihun; Ran, Lixin; Xin, Hao

    2014-12-01

    Artificial effective media are attractive because of the fantastic applications they may enable, such as super lensing and electromagnetic invisibility. However, the inevitable loss due to their strongly dispersive nature is one of the fundamental challenges preventing such applications from becoming a reality. In this study, we demonstrate an effective gain medium based on negative resistance, to overcompensate the loss of a conventional passive metamaterial, meanwhile keeping its original negative-index property. Energy conservation-based theory, full-wave simulation and experimental measurement show that a fabricated sample consisting of conventional sub-wavelength building blocks with embedded microwave tunnel diodes exhibits a band-limited Lorentzian dispersion simultaneously with a negative refractive index and a net gain. Our work provides experimental evidence to the assertion that a stable net gain in negative-index gain medium is achievable, proposing a potential solution for the critical challenge current metamateiral technology faces in practical applications.

  9. Spectrally encoded confocal microscopy for diagnosing breast cancer in excision and margin specimens.

    PubMed

    Brachtel, Elena F; Johnson, Nicole B; Huck, Amelia E; Rice-Stitt, Travis L; Vangel, Mark G; Smith, Barbara L; Tearney, Guillermo J; Kang, Dongkyun

    2016-04-01

    A large percentage of breast cancer patients treated with breast conserving surgery need to undergo multiple surgeries due to positive margins found during post-operative margin assessment. Carcinomas could be removed completely during the initial surgery and additional surgery avoided if positive margins can be determined intraoperatively. Spectrally encoded confocal microscopy (SECM) is a high-speed reflectance confocal microscopy technology that has a potential to rapidly image the entire surgical margin at subcellular resolution and accurately determine margin status intraoperatively. In this study, in order to test the feasibility of using SECM for intraoperative margin assessment, we have evaluated the diagnostic accuracy of SECM for detecting various types of breast cancers. Forty-six surgically removed breast specimens were imaged with an SECM system. Side-by-side comparison between SECM and histologic images showed that SECM images can visualize key histomorphologic patterns of normal/benign and malignant breast tissues. Small (500 μm × 500 μm) spatially registered SECM and histologic images (n=124 for each) were diagnosed independently by three pathologists with expertise in breast pathology. Diagnostic accuracy of SECM for determining malignant tissues was high, average sensitivity of 0.91, specificity of 0.93, positive predictive value of 0.95, and negative predictive value of 0.87. Intra-observer agreement and inter-observer agreement for SECM were also high, 0.87 and 0.84, respectively. Results from this study suggest that SECM may be developed into an intraoperative margin assessment tool for guiding breast cancer excisions. PMID:26779830

  10. Clinical significance of surgical margin status in patients subjected to radical prostatectomy.

    PubMed

    Dobruch, Jakub; Nyk, Lukasz; Skrzypczyk, Michał; Chłosta, Piotr; Dzik, Tomasz; Borówka, Andrzej

    2012-01-01

    The aim of this study is to evaluate the clinical value of positive surgical margins (PSM) in patients subjected to radical prostatectomy (RP). The data of men who were subjected to RP from the 1st of January, 2001 to the 30th of May, 2010 were analyzed. Specimens with PSM were again evaluated to confirm the presence of positive margins. PSM were found in 64 (25%) out of 255 analyzed patients. Out of all clinical features, only biopsy Gleason score and clinical stage of the disease were found to be predictive of PSM. Biochemical recurrence (BR) was found in 42 (16.5%) men, among them 17 (26.6%) had PSM and 25 (13.1%) had negative margins. The risk of BR in those with "focal" PSM (<3 mm) did not differ from the risk of BR observed in patients without PSM. In contrast, the likelihood of BR was significantly greater in cases of PSM in which maximum longitude exceeded 3 mm. Reevaluation of the PSM specimens revealed equivocal margins status in six cases. PSM are not inevitably associated with BR. The risk of failure is influenced by their length. Reevaluation of the prostate specimen may lead to surgical margins status modification. PMID:24578961

  11. Potential negative ecological effects of corridors.

    PubMed

    Haddad, Nick M; Brudvig, Lars A; Damschen, Ellen I; Evans, Daniel M; Johnson, Brenda L; Levey, Douglas J; Orrock, John L; Resasco, Julian; Sullivan, Lauren L; Tewksbury, Josh J; Wagner, Stephanie A; Weldon, Aimee J

    2014-10-01

    Despite many studies showing that landscape corridors increase dispersal and species richness for disparate taxa, concerns persist that corridors can have unintended negative effects. In particular, some of the same mechanisms that underlie positive effects of corridors on species of conservation interest may also increase the spread and impact of antagonistic species (e.g., predators and pathogens), foster negative effects of edges, increase invasion by exotic species, increase the spread of unwanted disturbances such as fire, or increase population synchrony and thus reduce persistence. We conducted a literature review and meta-analysis to evaluate the prevalence of each of these negative effects. We found no evidence that corridors increase unwanted disturbance or non-native species invasion; however, these have not been well-studied concerns (1 and 6 studies, respectively). Other effects of corridors were more often studied and yielded inconsistent results; mean effect sizes were indistinguishable from zero. The effect of edges on abundances of target species was as likely to be positive as negative. Corridors were as likely to have no effect on antagonists or population synchrony as they were to increase those negative effects. We found 3 deficiencies in the literature. First, despite studies on how corridors affect predators, there are few studies of related consequences for prey population size and persistence. Second, properly designed studies of negative corridor effects are needed in natural corridors at scales larger than those achievable in experimental systems. Third, studies are needed to test more targeted hypotheses about when corridor-mediated effects on invasive species or disturbance may be negative for species of management concern. Overall, we found no overarching support for concerns that construction and maintenance of habitat corridors may result in unintended negative consequences. Negative edge effects may be mitigated by widening

  12. Negative refraction and superconductivity

    NASA Astrophysics Data System (ADS)

    Amariti, Antonio; Forcella, Davide; Mariotti, Alberto; Siani, Massimo

    2011-10-01

    We discuss exotic properties of charged hydrodynamical systems, in the broken superconducting phase, probed by electromagnetic waves. Motivated by general arguments from hydrodynamics, we observe that negative refraction, namely the propagation in opposite directions of the phase velocities and of the energy flux, is expected for low enough frequencies. We corroborate this general idea by analyzing a holographic superconductor in the AdS/CFT correspondence, where the response functions can be explicitly computed. We study the dual gravitational theory both in the probe and in the backreacted case. We find that, while in the first case the refractive index is positive at every frequency, in the second case there is negative refraction at low enough frequencies. This is in agreement with hydrodynamic considerations.

  13. Think (Gram) negative!

    PubMed Central

    2010-01-01

    The increasing prevalence of multiresistant Gram-negative bacteria of the Enterobacteriaceae family in Europe is a worrisome phenomenon. Extended spectrum betalactamase-producing Escherichia coli strains are widespread in the community and are frequently imported into the hospital. Of even more concern is the spread of carbapenem-resistant strains of Klebsiella spp. from regions where they are already endemic. Antibiotic use is a main driver of antibiotic resistance, which again increases broad spectrum antibiotic use, resulting in a vicious circle that is difficult to interrupt. The present commentary highlights important findings of a surveillance study of antimicrobial use and resistance in German ICUs over 8 years with a focus on Gram-negative resistance. PMID:20587087

  14. Numerical simulation of platelet margination in microcirculation

    NASA Astrophysics Data System (ADS)

    Zhao, Hong; Shaqfeh, Eric

    2009-11-01

    The adhesion of platelets to vascular walls is the first step in clotting. This process critically depends on the preferential concentration of platelets near walls. The presence of red blood cells, which are the predominant blood constituents, is known to affect the steady state platelet concentration and the dynamic platelet margination, but the underlying mechanism is not well understood to-day. We use a direct numerical simulation to study the platelet margination process, with particular emphasis on the Stokesian hydrodynamic interactions among red cells, platelets, and vessel walls. Well-known mechanical models are used for the shearing and bending stiffness of red cell membranes, and the stiffer platelets are modeled as rigid discoids. A boundary integral formulation is used to solve the flow field, where the numerical solution procedure is accelerated by a parallel O(N N) smooth particle-mesh Ewald method. The effects of red cell hematocrit and deformability will be discussed.

  15. Earthquakes at North Atlantic passive margins

    SciTech Connect

    Gregersen, S. ); Basham, P.W. )

    1989-01-01

    The main focus of this volume is the earthquakes that occur at and near the continental margins on both sides of the North Atlantic. The book, which contains the proceedings of the NATO workshop on Causes and Effects of Earthquakes at Passive Margins and in Areas of Postglacial Rebound on Both Sides of the North Atlantic, draws together the fields of geophysics, geology and geodesy to address the stress and strain in the Earth's crust. The resulting earthquakes produced on ancient geological fault zones and the associated seismic hazards these pose to man are also addressed. Postglacial rebound in North America and Fennoscandia is a minor source of earthquakes today, during the interglacial period, but evidence is presented to suggest that the ice sheets suppressed earthquake strain while they were in place, and released this strain as a pulse of significant earthquakes after the ice melted about 9000 years ago.

  16. The initiation of orogenic margin reverse faulting

    NASA Astrophysics Data System (ADS)

    Bailey, R. C.

    2002-04-01

    Laboratory values of rock friction coefficients suggest that reverse faulting should be very difficult to initiate by simple horizontal compression of the crust. Values of stresses required by Andersonian faulting may be an order of magnitude higher than those actually present in orogenic margins. A simple stress balance calculation shows that the effect of the excess lithostatic pressure under an elevated orogen, if transmitted laterally through a crustal ductile layer to the orogenic margin, is to provide sufficient hydraulic lift under the orogen flanks to initiate reverse faulting by direct lift, even with rock friction coefficients of order 0.8. The required orogenic elevation above surrounding ``normal'' lithosphere is about one fifth of the thickness of the brittle crust of the orogen. This elevation may be as small as 2 km in tectonically active regions. The mechanism works even in the absence of regional lithospheric compressive stresses.

  17. The multifaceted West Greenland passive margin

    NASA Astrophysics Data System (ADS)

    Breuer, Sonja; Damm, Volkmar; Block, Martin; Schreckenberger, Bernd; Heyde, Ingo; Nelson, Catherine; Kouwe, Wim

    2013-04-01

    The Baffin Bay located between Greenland and Canada, is the northward extension of the Labrador Sea. The Davis Strait High separates these two marine basins. The evolution of these basins is closely linked, and is as well affiliated to the opening of the North Atlantic Ocean. The opening history started in the Cretaceous with the formation of several terrestrial rift basins with a block-faulted, metamorphic Precambrian basement. The further opening of the Baffin Bay coincides with the volcanic activity (60.9-52.5 Ma) along the West Greenland margin (Storey et al., 1998). The subsequent seafloor spreading in the Baffin Bay is linked to the Labrador Sea by the Ungava Fault Zone (UFZ), which is the most prominent transform fault in this region. Two main problems are still unsolved: 1) There are clear indications for normal seafloor spreading in the Baffin Bay like the seaward dipping reflectors (SDRs) on the Canadian side (Skaarup et al., 2006) and on the Greenland side based on our data. On the other hand, associated magnetic spreading anomalies are not yet discovered in the Baffin Bay or are not formed. These findings may either point to slow or ultraslow spreading or underlying strongly extended continental crust and/or serpentinised mantle. 2) The Greenlandic margin is much wider than the Canadian. In addition, a breakup unconformity can only be traced on the Greenland side and is not reported for the Canadian side. Which process causes this asymmetric margin and differences in shelf width? Is it a result of asymmetric spreading or connected to volcanic activity during breakup processes? In summer 2008, a marine geoscientific expedition (MSM09/03) was conducted with the research vessel "Maria S. Merian" in the Davis Strait and southern Baffin Bay. Approximately 1800 km of multichannel reflection seismic data were acquired. To supplement the database, a subsequent marine geoscientific expedition ARK-XXV/3 with RV POLARSTERN in summer 2010 was conducted. In our

  18. Systematic mapping of the Spanish continental margin

    NASA Astrophysics Data System (ADS)

    Acosta, Juan; Muñoz, Araceli; Uchupi, Elazar

    2012-07-01

    For economic, environmental, recreational, military, and political reasons it is critical for coastal states to have up-to-date information on their marine margins. Spain began to acquire such data 17 years ago. From 1995 to the present, the Spanish Oceanographic Institute (IEO), a research organization of the state, has carried out a systematic geological and geophysical study of the Spanish margins. Among these projects are (1) the hydrographic and oceanographic study of the Spanish Exclusive Economic Zone (EEZ) that was implemented by the Navy Hydrographic Institute (IHM); (2) the Espace Project, a study of the Spanish continental shelf; and (3) the Capesme Project, which created fisheries maps of the Mediterranean Sea. The latter two projects were carried out in collaboration with the Secretariat General of the Sea (SGM).

  19. Marginal breaking of conformal SUSY QCD

    NASA Astrophysics Data System (ADS)

    Cleary, Kevin F.; Terning, John

    2016-07-01

    We provide an example of a 4D theory that exhibits the Contino-Pomarol-Rattazzi mechanism, where breaking conformal symmetry by an almost marginal operator leads to a light pseudo-Goldstone boson, the dilaton, and a parametrically suppressed contribution to vacuum energy. We consider SUSY QCD at the edge of the conformal window and break conformal symmetry by weakly gauging a subgroup of the flavor symmetry. Using Seiberg duality we show that for a range of parameters the singlet meson in the dual theory reaches the unitarity bound, however, this theory does not have a stable vacuum. We stabilize the vacuum with soft breaking terms, compute the mass of the dilaton, and determine the range of parameters where the leading contribution to the dilaton mass is from the almost marginal coupling.

  20. Stepwise Signal Extraction via Marginal Likelihood

    PubMed Central

    Du, Chao; Kao, Chu-Lan Michael

    2015-01-01

    This paper studies the estimation of stepwise signal. To determine the number and locations of change-points of the stepwise signal, we formulate a maximum marginal likelihood estimator, which can be computed with a quadratic cost using dynamic programming. We carry out extensive investigation on the choice of the prior distribution and study the asymptotic properties of the maximum marginal likelihood estimator. We propose to treat each possible set of change-points equally and adopt an empirical Bayes approach to specify the prior distribution of segment parameters. Detailed simulation study is performed to compare the effectiveness of this method with other existing methods. We demonstrate our method on single-molecule enzyme reaction data and on DNA array CGH data. Our study shows that this method is applicable to a wide range of models and offers appealing results in practice. PMID:27212739

  1. Negative Emissions Technology

    NASA Astrophysics Data System (ADS)

    Day, Danny

    2006-04-01

    Although `negative emissions' of carbon dioxide need not, in principle, involve use of biological processes to draw carbon out of the atmosphere, such `agricultural' sequestration' is the only known way to remove carbon from the atmosphere on time scales comparable to the time scale for anthropogenic increases in carbon emissions. In order to maintain the `negative emissions' the biomass must be used in such a way that the resulting carbon dioxide is separated and permanently sequestered. Two options for sequestration are in the topsoil and via geologic carbon sequestration. The former has multiple benefits, but the latter also is needed. Thus, although geologic carbon sequestration is viewed skeptically by some environmentalists as simply a way to keep using fossil fuels---it may be a key part of reversing accelerating climate forcing if rapid climate change is beginning to occur. I will first review the general approach of agricultural sequestration combined with use of resulting biofuels in a way that permits carbon separation and then geologic sequestration as a negative emissions technology. Then I discuss the process that is the focus of my company---the EPRIDA cycle. If deployed at a sufficiently large scale, it could reverse the increase in CO2 concentrations. I also estimate of benefits --carbon and other---of large scale deployment of negative emissions technologies. For example, using the EPRIDA cycle by planting and soil sequestering carbon in an area abut In 3X the size of Texas would remove the amount of carbon that is being accumulated worldwide each year. In addition to the atmospheric carbon removal, the EPRIDA approach also counters the depletion of carbon in the soil---increasing topsoil and its fertility; reduces the excess nitrogen in the water by eliminating the need for ammonium nitrate fertilizer and reduces fossil fuel reliance by providing biofuel and avoiding natural gas based fertilizer production.

  2. Marginal Bidding: An Application of the Equimarginal Principle to Bidding in TAC SCM

    NASA Astrophysics Data System (ADS)

    Greenwald, Amy; Naroditskiy, Victor; Odean, Tyler; Ramirez, Mauricio; Sodomka, Eric; Zimmerman, Joe; Cutler, Clark

    We present a fast and effective bidding strategy for the Trading Agent Competition in Supply Chain Management (TAC SCM). In TAC SCM, manufacturers compete to procure computer parts from suppliers (the procurement problem), and then sell assembled computers to customers in reverse auctions (the bidding problem). This paper is concerned only with bidding, in which an agent must decide how many computers to sell and at what prices to sell them. We propose a greedy solution, Marginal Bidding, inspired by the Equimarginal Principle, which states that revenue is maximized among possible uses of a resource when the return on the last unit of the resource is the same across all areas of use. We show experimentally that certain variations of Marginal Bidding can compute bids faster than our ILP solution, which enables Marginal Bidders to consider future demand as well as current demand, and hence achieve greater revenues when knowledge of the future is valuable.

  3. An Artificial Immune Univariate Marginal Distribution Algorithm

    NASA Astrophysics Data System (ADS)

    Zhang, Qingbin; Kang, Shuo; Gao, Junxiang; Wu, Song; Tian, Yanping

    Hybridization is an extremely effective way of improving the performance of the Univariate Marginal Distribution Algorithm (UMDA). Owing to its diversity and memory mechanisms, artificial immune algorithm has been widely used to construct hybrid algorithms with other optimization algorithms. This paper proposes a hybrid algorithm which combines the UMDA with the principle of general artificial immune algorithm. Experimental results on deceptive function of order 3 show that the proposed hybrid algorithm can get more building blocks (BBs) than the UMDA.

  4. Neotectonics in the northern equatorial Brazilian margin

    NASA Astrophysics Data System (ADS)

    Rossetti, Dilce F.; Souza, Lena S. B.; Prado, Renato; Elis, Vagner R.

    2012-08-01

    An increasing volume of publications has addressed the role of tectonics in inland areas of northern Brazil during the Neogene and Quaternary, despite its location in a passive margin. Hence, northern South America plate in this time interval might have not been as passive as usually regarded. This proposal needs further support, particularly including field data. In this work, we applied an integrated approach to reveal tectonic structures in Miocene and late Quaternary strata in a coastal area of the Amazonas lowland. The investigation, undertaken in Marajó Island, mouth of the Amazonas River, consisted of shallow sub-surface geophysical data including vertical electric sounding and ground penetrating radar. These methods were combined with morphostructural analysis and sedimentological/stratigraphic data from shallow cores and a few outcrops. The results revealed two stratigraphic units, a lower one with Miocene age, and an upper one of Late Pleistocene-Holocene age. An abundance of faults and folds were recorded in the Miocene deposits and, to a minor extent, in overlying Late Pleistocene-Holocene strata. In addition to characterize these structures, we discuss their origin, considering three potential mechanisms: Andean tectonics, gravity tectonics related to sediment loading in the Amazon Fan, and rifting at the continental margin. Amongst these hypotheses, the most likely is that the faults and folds recorded in Marajó Island reflect tectonics associated with the history of continental rifting that gave rise to the South Atlantic Ocean. This study supports sediment deposition influenced by transpression and transtension associated with strike-slip divergence along the northern Equatorial Brazilian margin in the Miocene and Late Pleistocene-Holocene. This work records tectonic evidence only for the uppermost few ten of meters of this sedimentary succession. However, available geological data indicate a thickness of up to 6 km, which is remarkably thick for

  5. Analyzing marginal cases in differential shotgun proteomics

    PubMed Central

    Carvalho, Paulo C.; Fischer, Juliana S. G.; Perales, Jonas; Yates, John R.; Barbosa, Valmir C.; Bareinboim, Elias

    2011-01-01

    Summary: We present an approach to statistically pinpoint differentially expressed proteins that have quantitation values near the quantitation threshold and are not identified in all replicates (marginal cases). Our method uses a Bayesian strategy to combine parametric statistics with an empirical distribution built from the reproducibility quality of the technical replicates. Availability:The software is freely available for academic use at http://pcarvalho.com/patternlab. Contact: paulo@pcarvalho.com Supplementary information: Supplementary data are available at Bioinformatics online. PMID:21075743

  6. The negative repetition effect.

    PubMed

    Mulligan, Neil W; Peterson, Daniel J

    2013-09-01

    A fundamental property of human memory is that repetition enhances memory. Peterson and Mulligan (2012) recently documented a surprising negative repetition effect, in which participants who studied a list of cue-target pairs twice recalled fewer targets than a group who studied the pairs only once. Words within a pair rhymed, and across pairs, the target words were drawn from a small set of categories. In the repetition condition, the pairs were initially presented in a random order and then presented a 2nd time blocked by the category of the target words. In the single presentation condition, the pairs were presented only in the blocked order. Participants in the former condition recalled fewer target words on a free recall test despite having seen the word pairs twice (the negative repetition effect). This phenomenon is explored in a series of 5 experiments assessing 3 theoretical accounts of the effect. The experiments demonstrate that the negative repetition effect generalizes over multiple encoding conditions (reading and generative encoding), over different memory tests (free and cued recall), and over delay (5 min and 2 days). The results argue against a retrieval account and a levels-of-processing account but are consistent with the item-specific-relational account, the account upon which the effect was initially predicated. PMID:23421508

  7. The effect of wide resection margin in patients with intrahepatic cholangiocarcinoma

    PubMed Central

    Ma, Ka Wing; Cheung, Tan To; She, Wong Hoi; Chok, Kenneth S.H.; Chan, Albert Chi Yan; Ng, Irene Oi Lin; Chan, See Ching; Lo, Chung Mau

    2016-01-01

    Abstract Introduction: Prognosis of intrahepatic cholangiocarcinoma (ICC) remained poor despite the multitude advancement of medical care. Resection margin status is one of the few modifiable factors that a surgeon could possibly manipulate to alter the disease outcome. However, the significance of margin status and margin width is still controversial. This study serves to further elucidate the role of them. Method: This is a retrospective cohort from the Queen Mary Hospital, The University of Hong Kong. Consecutive patients diagnosed to have ICC and with surgical resection performed in curative intent were retrieved, while patients with cholangiohepatocellular carcinoma, Klaskin tumor, tumor of extrahepatic bile duct, and uncertain tumor pathology were excluded. Results: From 1991 to 2013, there were 107 patients underwent hepatectomy for ICC. Gender predilection was not observed with 58 males and 49 females, median age of the patients was 61. The median tumor size was 6 cm and most of them (43%) were moderately differentiated adenocarcinoma. Clear resection margin were achieved in 95 patients (88.8%) and the median margin width was 0.5 cm. The hospital length of stay and operative mortality were 11 days and 3%, respectively. The disease-free survival and overall survival were 17.5 and 25.1 months, respectively. Multivariate analysis showed that margin width was an independent factor associated with disease-free survival (P = 0.015, 95% confidence interval [CI] 0.4–0.9). Subgroup analysis in patients with solitary tumor showed that margin width is an independent factor affecting overall survival (P = 0.048; odds ratio: 0.577; 95% CI: 0.334–0.996). Discriminant analysis showed that the overall survival increased from 36 to 185 months when margin width was >0.9 cm (P = 0.025) in patients with solitary tumor. Conclusion: Aggressive resection to achieve resection margin of at least 1 cm maximizes chance of cure in patients with early ICC. PMID:27428200

  8. On Bayesian estimation of marginal structural models.

    PubMed

    Saarela, Olli; Stephens, David A; Moodie, Erica E M; Klein, Marina B

    2015-06-01

    The purpose of inverse probability of treatment (IPT) weighting in estimation of marginal treatment effects is to construct a pseudo-population without imbalances in measured covariates, thus removing the effects of confounding and informative censoring when performing inference. In this article, we formalize the notion of such a pseudo-population as a data generating mechanism with particular characteristics, and show that this leads to a natural Bayesian interpretation of IPT weighted estimation. Using this interpretation, we are able to propose the first fully Bayesian procedure for estimating parameters of marginal structural models using an IPT weighting. Our approach suggests that the weights should be derived from the posterior predictive treatment assignment and censoring probabilities, answering the question of whether and how the uncertainty in the estimation of the weights should be incorporated in Bayesian inference of marginal treatment effects. The proposed approach is compared to existing methods in simulated data, and applied to an analysis of the Canadian Co-infection Cohort. PMID:25677103

  9. Ocean Margins Programs, Phase I research summaries

    SciTech Connect

    Verity, P.

    1994-08-01

    During FY 1992, the DOE restructured its regional coastal-ocean programs into a new Ocean Margins Program (OMP), to: Quantify the ecological and biogeochemical processes and mechanisms that affect the cycling, flux, and storage of carbon and other biogenic elements at the land/ocean interface; Define ocean-margin sources and sinks in global biogeochemical cycles, and; Determine whether continental shelves are quantitatively significant in removing carbon dioxide from the atmosphere and isolating it via burial in sediments or export to the interior ocean. Currently, the DOE Ocean Margins Program supports more than 70 principal and co-principal investigators, spanning more than 30 academic institutions. Research funded by the OMP amounted to about $6.9M in FY 1994. This document is a collection of abstracts summarizing the component projects of Phase I of the OMP. This phase included both research and technology development, and comprised projects of both two and three years duration. The attached abstracts describe the goals, methods, measurement scales, strengths and limitations, and status of each project, and level of support. Keywords are provided to index the various projects. The names, addresses, affiliations, and major areas of expertise of the investigators are provided in appendices.

  10. Origin and Dynamics of Depositionary Forearc Margins

    NASA Astrophysics Data System (ADS)

    Vannucchi, Paola; Morgan, Jason

    2015-04-01

    Depositionary forearcs are built by terrigenous sediments that never reach the axis of a trench. It has been usually thought that at subduction zones, terrigenous sediments shed from the continent drape the upper plate slope, accumulate in aprons or forearc basins, and can easily reach the trench as turbidites or mass slope deposits. Here we propose a new framework for forearc evolution that focuses on the potential feedbacks between subduction tectonics, sedimentation and geomorphology that take place during an extreme event of subduction erosion, such as the onset of subduction of a major aseismic ridge. There subduction erosion has the potential to rapidly remove the upper plate basement, and replace it from above by rapidly redeposited sediments. This feedback can lead to the creation of "depositionary forearcs", a forearc structure that extends the traditional division of forearcs into accretionary vs. erosive subduction margins, and which emphasizes the dynamic evolution processes at these margins. We need to further recognize that subduction forearcs are usually shaped by interactions between slow long term processes and severe punctuated events reflecting the sudden influences of large-scale morphological variations in the incoming plate. Both types of processes contribute to the large-scale morphology of the forearc, with sudden events associated with a replacive depositionary mode that can suddenly create a sub-section of a typical forearc margin.

  11. Observation and Analysis of Resistive Instabilities in Negative Central Shear in DIII-D Discharges with L-Mode Edge

    SciTech Connect

    Jayakumar, R.J.; Austin, M.E.; Brennan, D.P.; Chu, M.S.; Luce, T.C.; Strait, E.J.; Turnbull, A.D.

    2002-07-01

    In DIII-D plasmas with L-mode edge and negative central shear (q{sub axis}-q{sub min} {approx}0.3 to 0.5), an interchange-like instability has been observed [1]. The instability and a subsequent tearing mode cause reduction of the core electron temperature and plasma rotation, and therefore the instability affects discharge evolution and the desired high performance is not achieved. Stability analyses indicate robust ideal stability, while the Resistive Interchange Mode criterion is marginal and the instability appears to be localized initially. Based on this, we believe that the mode is, most likely, a Resistive Interchange Mode. The amplitude of the instability is correlated with the location of the q{sub min} surface and inversely with the fast-ion pressure. There is indication that the interchange-like instability may be ''seeding'' the tearing mode that sometimes follows the interchange-like instability.

  12. Explorations in achievement motivation

    NASA Technical Reports Server (NTRS)

    Helmreich, Robert L.

    1982-01-01

    Recent research on the nature of achievement motivation is reviewed. A three-factor model of intrinsic motives is presented and related to various criteria of performance, job satisfaction and leisure activities. The relationships between intrinsic and extrinsic motives are discussed. Needed areas for future research are described.

  13. Achieving health care affordability.

    PubMed

    Payson, Norman C

    2002-10-01

    Not all plans are jumping headlong into the consumer-centric arena. In this article, the CEO of Oxford Health Plans discusses how advanced managed care can achieve what other consumer-centric programs seek to do--provide affordable, quality health care. PMID:12391815

  14. Issues in Achievement Testing.

    ERIC Educational Resources Information Center

    Baker, Eva L.

    This booklet is intended to help school personnel, parents, students, and members of the community understand concepts and research relating to achievement testing in public schools. The paper's sections include: (1) test use with direct effects on students (test of certification, selection, and placement); (2) test use with indirect effects on…

  15. Achieving Peace through Education.

    ERIC Educational Resources Information Center

    Clarken, Rodney H.

    While it is generally agreed that peace is desirable, there are barriers to achieving a peaceful world. These barriers are classified into three major areas: (1) an erroneous view of human nature; (2) injustice; and (3) fear of world unity. In a discussion of these barriers, it is noted that although the consciousness and conscience of the world…

  16. Achieving All Our Ambitions

    ERIC Educational Resources Information Center

    Hartley, Tricia

    2009-01-01

    National learning and skills policy aims both to build economic prosperity and to achieve social justice. Participation in higher education (HE) has the potential to contribute substantially to both aims. That is why the Campaign for Learning has supported the ambition to increase the proportion of the working-age population with a Level 4…

  17. Intelligence and Educational Achievement

    ERIC Educational Resources Information Center

    Deary, Ian J.; Strand, Steve; Smith, Pauline; Fernandes, Cres

    2007-01-01

    This 5-year prospective longitudinal study of 70,000+ English children examined the association between psychometric intelligence at age 11 years and educational achievement in national examinations in 25 academic subjects at age 16. The correlation between a latent intelligence trait (Spearman's "g"from CAT2E) and a latent trait of educational…

  18. SALT and Spelling Achievement.

    ERIC Educational Resources Information Center

    Nelson, Joan

    A study investigated the effects of suggestopedic accelerative learning and teaching (SALT) on the spelling achievement, attitudes toward school, and memory skills of fourth-grade students. Subjects were 20 male and 28 female students from two self-contained classrooms at Kennedy Elementary School in Rexburg, Idaho. The control classroom and the…

  19. NCLB: Achievement Robin Hood?

    ERIC Educational Resources Information Center

    Bracey, Gerald W.

    2008-01-01

    In his "Wall Street Journal" op-ed on the 25th of anniversary of "A Nation At Risk", former assistant secretary of education Chester E. Finn Jr. applauded the report for turning U.S. education away from equality and toward achievement. It was not surprising, then, that in mid-2008, Finn arranged a conference to examine the potential "Robin Hood…

  20. INTELLIGENCE, PERSONALITY AND ACHIEVEMENT.

    ERIC Educational Resources Information Center

    MUIR, R.C.; AND OTHERS

    A LONGITUDINAL DEVELOPMENTAL STUDY OF A GROUP OF MIDDLE CLASS CHILDREN IS DESCRIBED, WITH EMPHASIS ON A SEGMENT OF THE RESEARCH INVESTIGATING THE RELATIONSHIP OF ACHIEVEMENT, INTELLIGENCE, AND EMOTIONAL DISTURBANCE. THE SUBJECTS WERE 105 CHILDREN AGED FIVE TO 6.3 ATTENDING TWO SCHOOLS IN MONTREAL. EACH CHILD WAS ASSESSED IN THE AREAS OF…

  1. School Students' Science Achievement

    ERIC Educational Resources Information Center

    Shymansky, James; Wang, Tzu-Ling; Annetta, Leonard; Everett, Susan; Yore, Larry D.

    2013-01-01

    This paper is a report of the impact of an externally funded, multiyear systemic reform project on students' science achievement on a modified version of the Third International Mathematics and Science Study (TIMSS) test in 33 small, rural school districts in two Midwest states. The systemic reform effort utilized a cascading leadership strategy…

  2. Advancing Student Achievement

    ERIC Educational Resources Information Center

    Walberg, Herbert J.

    2010-01-01

    For the last half century, higher spending and many modern reforms have failed to raise the achievement of students in the United States to the levels of other economically advanced countries. A possible explanation, says Herbert Walberg, is that much current education theory is ill informed about scientific psychology, often drawing on fads and…

  3. Essays on Educational Achievement

    ERIC Educational Resources Information Center

    Ampaabeng, Samuel Kofi

    2013-01-01

    This dissertation examines the determinants of student outcomes--achievement, attainment, occupational choices and earnings--in three different contexts. The first two chapters focus on Ghana while the final chapter focuses on the US state of Massachusetts. In the first chapter, I exploit the incidence of famine and malnutrition that resulted to…

  4. Increasing Male Academic Achievement

    ERIC Educational Resources Information Center

    Jackson, Barbara Talbert

    2008-01-01

    The No Child Left Behind legislation has brought greater attention to the academic performance of American youth. Its emphasis on student achievement requires a closer analysis of assessment data by school districts. To address the findings, educators must seek strategies to remedy failing results. In a mid-Atlantic district of the Unites States,…

  5. Setting and Achieving Objectives.

    ERIC Educational Resources Information Center

    Knoop, Robert

    1986-01-01

    Provides basic guidelines which school officials and school boards may find helpful in negotiating, establishing, and managing objectives. Discusses characteristics of good objectives, specific and directional objectives, multiple objectives, participation in setting objectives, feedback on goal process and achievement, and managing a school…

  6. Schools Achieving Gender Equity.

    ERIC Educational Resources Information Center

    Revis, Emma

    This guide is designed to assist teachers presenting the Schools Achieving Gender Equity (SAGE) curriculum for vocational education students, which was developed to align gender equity concepts with the Kentucky Education Reform Act (KERA). Included in the guide are lesson plans for classes on the following topics: legal issues of gender equity,…

  7. Iowa Women of Achievement.

    ERIC Educational Resources Information Center

    Ohrn, Deborah Gore, Ed.

    1993-01-01

    This issue of the Goldfinch highlights some of Iowa's 20th century women of achievement. These women have devoted their lives to working for human rights, education, equality, and individual rights. They come from the worlds of politics, art, music, education, sports, business, entertainment, and social work. They represent Native Americans,…

  8. Achievements or Disasters?

    ERIC Educational Resources Information Center

    Goodwin, MacArthur

    2000-01-01

    Focuses on policy issues that have affected arts education in the twentieth century, such as: interest in discipline-based arts education, influence of national arts associations, and national standards and coordinated assessment. States that whether the policy decisions are viewed as achievements or disasters are for future determination. (CMK)

  9. Minority Achievement Report.

    ERIC Educational Resources Information Center

    Prince George's Community Coll., Largo, MD. Office of Institutional Research and Analysis.

    This report summarizes the achievements of Prince George's Community College (PGCC) with regard to minority outcomes. Table 1 summarizes the undergraduate enrollment trends for African Americans as well as total minorities from fall 1994 through fall 1998. Both the headcount number of African American students and the proportion of African…

  10. Appraising Reading Achievement.

    ERIC Educational Resources Information Center

    Ediger, Marlow

    To determine quality sequence in pupil progress, evaluation approaches need to be used which guide the teacher to assist learners to attain optimally. Teachers must use a variety of procedures to appraise student achievement in reading, because no one approach is adequate. Appraisal approaches might include: (1) observation and subsequent…

  11. Flexible Control of Safety Margins for Action Based on Environmental Variability

    PubMed Central

    Hadjiosif, Alkis M.

    2015-01-01

    To reduce the risk of slip, grip force (GF) control includes a safety margin above the force level ordinarily sufficient for the expected load force (LF) dynamics. The current view is that this safety margin is based on the expected LF dynamics, amounting to a static safety factor like that often used in engineering design. More efficient control could be achieved, however, if the motor system reduces the safety margin when LF variability is low and increases it when this variability is high. Here we show that this is indeed the case by demonstrating that the human motor system sizes the GF safety margin in proportion to an internal estimate of LF variability to maintain a fixed statistical confidence against slip. In contrast to current models of GF control that neglect the variability of LF dynamics, we demonstrate that GF is threefold more sensitive to the SD than the expected value of LF dynamics, in line with the maintenance of a 3-sigma confidence level. We then show that a computational model of GF control that includes a variability-driven safety margin predicts highly asymmetric GF adaptation between increases versus decreases in load. We find clear experimental evidence for this asymmetry and show that it explains previously reported differences in how rapidly GFs and manipulatory forces adapt. This model further predicts bizarre nonmonotonic shapes for GF learning curves, which are faithfully borne out in our experimental data. Our findings establish a new role for environmental variability in the control of action. PMID:26085634

  12. Radial gravitational gliding on passive margins

    NASA Astrophysics Data System (ADS)

    Cobbold, P. R.; Szatmari, P.

    1991-03-01

    Gravitational gliding of uppermost sediments down a passive margin is possible if there is a basal layer of evaporite or other soft material to allow detachment. In examples from the Gulf of Mexico and the Brazilian margin, gliding has produced three main structural domains: an uppermost domain of downdip extension; an intermediate domain of rigid gliding; and a lowermost domain of downdip contraction. Domain boundaries are established by changes in slope. In this paper, we examine three kinds of gravitational gliding, depending on the paths followed by material particles. In ideal parallel gliding, particle paths are parallel straight lines, trending downslope. This should occur where the margin is perfectly straight. In ideal radial gliding, particle paths are radii of a circle and the margin is shaped like a circular cone. Natural margins will not have ideal shapes; but divergent gliding will tend to occur off coastal salients; convergent gliding, off coastal re-entrants. A simple kinematic model based on ductile behaviour illustrates some essential features of radial gliding. Changes in radius during divergent gliding produce strike-parallel extension; during convergent gliding, they produce strike-parallel contraction. Vertical strains also differ. Divergent gliding produces an uppermost domain of strong vertical thinning, balanced by extensions in all horizontal directions. Similarly, convergent gliding produces a lowermost domain of strong vertical thickening, balanced by contractions in all horizontal directions. These deformed states cannot be restored by simple techniques based on section balancing. We have done three experiments using analogue materials: sand, to model the brittle behaviour of sediments; silicone putty, to model the ductile behaviour of basal layers of evaporite. The experiments were properly scaled to account for gravitational forces. Experiment I reproduced convergent gliding above a basement with a conical upper surface. Strike

  13. Negated bio-events: analysis and identification

    PubMed Central

    2013-01-01

    Background Negation occurs frequently in scientific literature, especially in biomedical literature. It has previously been reported that around 13% of sentences found in biomedical research articles contain negation. Historically, the main motivation for identifying negated events has been to ensure their exclusion from lists of extracted interactions. However, recently, there has been a growing interest in negative results, which has resulted in negation detection being identified as a key challenge in biomedical relation extraction. In this article, we focus on the problem of identifying negated bio-events, given gold standard event annotations. Results We have conducted a detailed analysis of three open access bio-event corpora containing negation information (i.e., GENIA Event, BioInfer and BioNLP’09 ST), and have identified the main types of negated bio-events. We have analysed the key aspects of a machine learning solution to the problem of detecting negated events, including selection of negation cues, feature engineering and the choice of learning algorithm. Combining the best solutions for each aspect of the problem, we propose a novel framework for the identification of negated bio-events. We have evaluated our system on each of the three open access corpora mentioned above. The performance of the system significantly surpasses the best results previously reported on the BioNLP’09 ST corpus, and achieves even better results on the GENIA Event and BioInfer corpora, both of which contain more varied and complex events. Conclusions Recently, in the field of biomedical text mining, the development and enhancement of event-based systems has received significant interest. The ability to identify negated events is a key performance element for these systems. We have conducted the first detailed study on the analysis and identification of negated bio-events. Our proposed framework can be integrated with state-of-the-art event extraction systems. The

  14. Robust Flutter Margin Analysis that Incorporates Flight Data

    NASA Technical Reports Server (NTRS)

    Lind, Rick; Brenner, Martin J.

    1998-01-01

    An approach for computing worst-case flutter margins has been formulated in a robust stability framework. Uncertainty operators are included with a linear model to describe modeling errors and flight variations. The structured singular value, mu, computes a stability margin that directly accounts for these uncertainties. This approach introduces a new method of computing flutter margins and an associated new parameter for describing these margins. The mu margins are robust margins that indicate worst-case stability estimates with respect to the defined uncertainty. Worst-case flutter margins are computed for the F/A-18 Systems Research Aircraft using uncertainty sets generated by flight data analysis. The robust margins demonstrate flight conditions for flutter may lie closer to the flight envelope than previously estimated by p-k analysis.

  15. A 2 X 2 achievement goal framework.

    PubMed

    Elliot, A J; McGregor, H A

    2001-03-01

    A 2 x 2 achievement goal framework comprising mastery-approach, mastery-avoidance, performance-approach, and performance-avoidance goals was proposed and tested in 3 studies. Factor analytic results supported the independence of the 4 achievement goal constructs. The goals were examined with respect to several important antecedents (e.g., motive dispositions, implicit theories, socialization histories) and consequences (e.g., anticipatory test anxiety, exam performance, health center visits), with particular attention allocated to the new mastery-avoidance goal construct. The results revealed distinct empirical profiles for each of the achievement goals; the pattern for mastery-avoidance goals was, as anticipated, more negative than that for mastery-approach goals and more positive than that for performance-avoidance goals. Implications of the present work for future theoretical development in the achievement goal literature are discussed. PMID:11300582

  16. Fitness and survival in fragmented populations of Narthecium ossifragum at the species' range margin

    NASA Astrophysics Data System (ADS)

    Tsaliki, Marina; Diekmann, Martin

    2009-05-01

    Decreasing population size and increasing isolation may lead to reduced plant fitness. These effects of habitat fragmentation may especially apply to populations close to the margin of their geographical range, where populations generally are often smaller and more isolated, and the environment is less favourable than at the range centre. In this context we studied north-west German range-margin populations of Narthecium ossifragum (L.) HUDS., a clonal, perennial herb typical for acidic and nutrient-poor wet heathlands. We asked whether plant fitness and reproduction of the range-margin populations were affected by population size and habitat quality, and whether any changes in population size over the past 10-20 years were related to past population size and habitat quality. Population size varied between 60 and 100.000 individuals and was highly positively related to shoot density. Larger (and denser) populations formed more flowers and fruits, but fewer seeds. Soil water content had a strong positive effect on seed production and seed mass, and the latter also increased with increasing soil phosphorus content. Relative light intensity showed a positive impact on shoot density and, hence, population size. Compared to British range centre populations, the populations at the German range margin formed more, but smaller seeds that failed to germinate both in the field and in laboratory experiments. Despite the lack of sexual reproduction, population sizes generally had not decreased during the past two decades, most likely due to successful clonal growth. The change in population size of Narthecium, however, was negatively related to the present soil phosphorus content, indicating that an increased supply of nutrients and a decrease in light availability may have a negative effect on population dynamics. The results imply that fragmented and small range-margin populations not necessarily are doomed to extinction, provided that the habitat quality remains suitable

  17. Carbonate comparison of west Florida continental margin with margins of eastern United States

    SciTech Connect

    Doyle, L.J.

    1986-05-01

    Temperate carbonate margins may have as many similarities to clastic margins as to other carbonate systems. An example is the west Florida continental margin north of Florida Bay, a vast area of more than 150,000 km/sup 2/. The facies of this area differ from those of other Holocene carbonates, such as the Bahama Banks, the Great Barrier Reef, and the Caribbean and Pacific bioherms. The west Florida margin is analogous to the predominantly clastic southeastern US in both physiology and sedimentary processes. The shelf facies is a veneer of carbonate sand, primarily molluscan shell fragments, with low sedimentation rates. It is similar to the southeastern US sand veneer with the clastic component removed. Like the US system, the west Florida shelf has a ridge and swale topography replete with sedimentary structures, such as sand waves, with a series of drainage systems incised into its surface at lower stands of sea level. On the outer edge, it is commonly bounded by outcrops with considerable positive relief. The upper slope of the west Florida margin is a calcilutite, a Holocene chalk deposit accumulating at rates of tens of centimeters/1000 years, comparable to the clastic lutite depositional rates of the eastern US continental slope, and two orders of magnitude higher than deep-sea oozes of similar composition. These relatively high rates are probably caused by fines pumped from and across the coarser shelf-sand sheets in both systems.

  18. Optimization of leaf margins for lung stereotactic body radiotherapy using a flattening filter-free beam

    SciTech Connect

    Wakai, Nobuhide; Sumida, Iori; Otani, Yuki; Suzuki, Osamu; Seo, Yuji; Isohashi, Fumiaki; Yoshioka, Yasuo; Ogawa, Kazuhiko; Hasegawa, Masatoshi

    2015-05-15

    Purpose: The authors sought to determine the optimal collimator leaf margins which minimize normal tissue dose while achieving high conformity and to evaluate differences between the use of a flattening filter-free (FFF) beam and a flattening-filtered (FF) beam. Methods: Sixteen lung cancer patients scheduled for stereotactic body radiotherapy underwent treatment planning for a 7 MV FFF and a 6 MV FF beams to the planning target volume (PTV) with a range of leaf margins (−3 to 3 mm). Forty grays per four fractions were prescribed as a PTV D95. For PTV, the heterogeneity index (HI), conformity index, modified gradient index (GI), defined as the 50% isodose volume divided by target volume, maximum dose (Dmax), and mean dose (Dmean) were calculated. Mean lung dose (MLD), V20 Gy, and V5 Gy for the lung (defined as the volumes of lung receiving at least 20 and 5 Gy), mean heart dose, and Dmax to the spinal cord were measured as doses to organs at risk (OARs). Paired t-tests were used for statistical analysis. Results: HI was inversely related to changes in leaf margin. Conformity index and modified GI initially decreased as leaf margin width increased. After reaching a minimum, the two values then increased as leaf margin increased (“V” shape). The optimal leaf margins for conformity index and modified GI were −1.1 ± 0.3 mm (mean ± 1 SD) and −0.2 ± 0.9 mm, respectively, for 7 MV FFF compared to −1.0 ± 0.4 and −0.3 ± 0.9 mm, respectively, for 6 MV FF. Dmax and Dmean for 7 MV FFF were higher than those for 6 MV FF by 3.6% and 1.7%, respectively. There was a positive correlation between the ratios of HI, Dmax, and Dmean for 7 MV FFF to those for 6 MV FF and PTV size (R = 0.767, 0.809, and 0.643, respectively). The differences in MLD, V20 Gy, and V5 Gy for lung between FFF and FF beams were negligible. The optimal leaf margins for MLD, V20 Gy, and V5 Gy for lung were −0.9 ± 0.6, −1.1 ± 0.8, and −2.1 ± 1.2 mm, respectively, for 7 MV FFF compared

  19. Project ACHIEVE final report

    SciTech Connect

    1997-06-13

    Project ACHIEVE was a math/science academic enhancement program aimed at first year high school Hispanic American students. Four high schools -- two in El Paso, Texas and two in Bakersfield, California -- participated in this Department of Energy-funded program during the spring and summer of 1996. Over 50 students, many of whom felt they were facing a nightmare future, were given the opportunity to work closely with personal computers and software, sophisticated calculators, and computer-based laboratories -- an experience which their regular academic curriculum did not provide. Math and science projects, exercises, and experiments were completed that emphasized independent and creative applications of scientific and mathematical theories to real world problems. The most important outcome was the exposure Project ACHIEVE provided to students concerning the college and technical-field career possibilities available to them.

  20. Principals' Perceived Supervisory Behaviors Regarding Marginal Teachers in Two States

    ERIC Educational Resources Information Center

    Range, Bret; Hewitt, Paul; Young, Suzie

    2014-01-01

    This descriptive study used an online survey to determine how principals in two states viewed the supervision of marginal teachers. Principals ranked their own evaluation of the teacher as the most important factor when identifying marginal teachers and relied on informal methods to diagnose marginal teaching. Female principals rated a majority of…

  1. 17 CFR 23.703 - Investment of segregated margin.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 17 Commodity and Securities Exchanges 1 2014-04-01 2014-04-01 false Investment of segregated... Transactions § 23.703 Investment of segregated margin. (a) Margin that is segregated pursuant to an election... commercial arrangement, in writing, regarding the investment of such Margin, and the related allocation...

  2. 17 CFR 260.7a-19 - Margin for binding.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Margin for binding. 260.7a-19...) GENERAL RULES AND REGULATIONS, TRUST INDENTURE ACT OF 1939 Formal Requirements § 260.7a-19 Margin for... and documents filed as a part thereof, shall have a back or stitching margin of at least 11/2...

  3. 17 CFR 260.7a-19 - Margin for binding.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 17 Commodity and Securities Exchanges 3 2011-04-01 2011-04-01 false Margin for binding. 260.7a-19...) GENERAL RULES AND REGULATIONS, TRUST INDENTURE ACT OF 1939 Formal Requirements § 260.7a-19 Margin for... and documents filed as a part thereof, shall have a back or stitching margin of at least 11/2...

  4. 46 CFR 171.015 - Location of margin line.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Location of margin line. 171.015 Section 171.015... PERTAINING TO VESSELS CARRYING PASSENGERS General § 171.015 Location of margin line. (a) A vessel with a... (FP) and the after perpendicular (AP) is at least 12 inches (30.5 cm), the margin line must be...

  5. 46 CFR 171.015 - Location of margin line.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 46 Shipping 7 2011-10-01 2011-10-01 false Location of margin line. 171.015 Section 171.015... PERTAINING TO VESSELS CARRYING PASSENGERS General § 171.015 Location of margin line. (a) A vessel with a... (FP) and the after perpendicular (AP) is at least 12 inches (30.5 cm), the margin line must be...

  6. Simulation Based on Ion Propulsion Rocket System with Using Negative ion - Negative Ion Pair Techniques

    NASA Astrophysics Data System (ADS)

    Sathiyavel, C.

    2016-07-01

    Ion propulsion rocket system is expected to become popular with the development of ion-ion pair techniques because of their stimulated of low propellant, Design of Thrust range is 1N with low electric power and high efficiency. A Negative ion-Negative ion pair of ion propulsion rocket system is proposed in this work .Negative Ion Based Rocket system consists of three parts 1.ionization chamber 2. Repulsion force and ion accelerator 3. Exhaust of Nozzle. The Negative ions from electro negatively gas are produced by attachment of the gas ,such as chlorine with electron emitted from a Electron gun ionization chamber. The formulate of large stable negative ion is achievable in chlorine gas with respect to electron affinity (∆E). The electron affinity is a measure of the energy change when an electron is added to a neutral atom to form a negative ion. When a neutral chlorine atom in the gaseous form picks up an electron to form a Cl- ion, it releases energy of 349 kJ/mol or 3.6 ev/atom. It is said to have an electron affinity of -349 kJ/mol ,the negative sign indicating that energy is released during this process .The mechanisms of attachment involve the formation of intermediate states. In that reason for , the highly repulsive force created between the same negative ions. The distance between same negative ions is important for the evaluate of the rocket thrust and is also determined by the exhaust velocity of the propellant. The mass flow rate of propellant is achieved by the ratio of total mass of the propellant (Kg) needed for operation to time period(s). Accelerate the Negative ions to a high velocity in the thrust vector direction with a significantly intense Magnetic field and the exhaust of negative ions through Nozzle. The simulation of the ion propulsion system has been carried out by MATLAB. By comparing the simulation results with the theoretical and previous results, we have found that the proposed method is achieved of thrust value with estimated

  7. Precessional control of Sr ratios in marginal basins during the Messinian Salinity Crisis?

    NASA Astrophysics Data System (ADS)

    Topper, R. P. M.; Lugli, S.; Manzi, V.; Roveri, M.; Meijer, P. Th.

    2014-05-01

    on 87Sr/86Sr data of the Primary Lower Gypsum (PLG) deposits in the Vena del Gesso basin—a marginal basin of the Mediterranean during the Messinian Salinity Crisis—a correlation between 87Sr/86Sr values and precessional forcing has recently been proposed but not yet confirmed. In this study, a box model is set up to represent the Miocene Mediterranean deep basin and a connected marginal basin. Measurements of 87Sr/86Sr in the Vena del Gesso and estimated salinity extrema are used to constrain model results. In an extensive analysis with this model, we assess whether coeval 87Sr/86Sr and salinity fluctuations could have been forced by precession-driven changes in the fresh water budget. A comprehensive set of the controlling parameters is examined to assess the conditions under which precession-driven 87Sr/86Sr variations occur and to determine the most likely setting for PLG formation. Model results show that precession-driven 87Sr/86Sr and salinity fluctuations in marginal basins are produced in settings within a large range of marginal basin sizes, riverine strontium characteristics, amplitudes of precessional fresh water budget variation, and average fresh water budgets of both the marginal and deep basin. PLG deposition most likely occurred when the Atlantic-Mediterranean connection was restricted, and the average fresh water budget in the Mediterranean was significantly less negative than at present day. Considering the large range of settings in which salinities and 87Sr/86Sr fluctuate on a precessional timescale, 87Sr/86Sr variations are expected to be a common feature in PLG deposits in marginal basins of the Mediterranean.

  8. Medical and Social Determinants of Subsequent Labour Market Marginalization in Young Hospitalized Suicide Attempters

    PubMed Central

    Niederkrotenthaler, Thomas; Tinghög, Petter; Goldman-Mellor, Sidra; Wilcox, Holly C.; Gould, Madelyn; Mittendorfer-Rutz, Ellenor

    2016-01-01

    Background Individuals with a history of suicide attempt have a high risk for subsequent labour market marginalization. This study aimed at assessing the effect of individual and parental factors on different measures of marginalization. Methods Prospective cohort study based on register linkage of 5 649 individuals who in 1994 were 16–30 years old, lived in Sweden and were treated in inpatient care for suicide attempt during 1992–1994. Hazard ratios (HRs) for labour market marginalization defined as long-term unemployment (>180 days), sickness absence (>90 days), or disability pension in 1995–2010 were calculated with Cox regression. Results Medical risk factors, particularly any earlier diagnosed specific mental disorders (e.g., schizophrenia: HR 5.4 (95% CI: 4.2, 7.0), personality disorders: HR 3.9, 95% CI: 3.1, 4.9), repetitive suicide attempts (HR 1.6, 95% CI: 1.4, 1.9) were associated with a higher relative risk of disability pension. Individual medical factors were of smaller importance for long-term sickness absence, and of only marginal relevance to long-term unemployment. Country of birth outside Europe had an opposite effect on disability pension (HR 0.6, 95% CI: 0.4, 0.8) and long-term unemployment (HR 1.5, 95% CI: 1.3, 1.8). Female sex was positively correlated with long-term sickness absence (HR 1.6, 95% CI: 1.4, 1.7), and negatively associated with long-term unemployment (HR: 0.8, 95% CI: 0.7, 0.9). Conclusions As compared to disability pension, long-term sickness absence and unemployment was more strongly related to socio-economic variables. Marginalization pathways seemed to vary with migration status and sex. These findings may contribute to the development of intervention strategies which take the individual risk for marginalization into account. PMID:26784886

  9. Negative-stiffness-mechanism vibration isolation systems

    NASA Astrophysics Data System (ADS)

    Platus, David L.

    1992-02-01

    A new type of vibration isolation system offers significant improvement in performance compared with current state-of-the-art systems. The system uses negative-stiffness mechanisms to cancel the stiffness of a spring suspension. Reduction in stiffness magnifies the damping inherent in the system creating a practical means for achieving high hysteretic damping. The result is a simple, compact 6-DOF passive isolation system capable of system resonant frequencies below 0.2 Hz and first isolator resonances above 100 Hz. Resonant transmissibilities below 1.4 can be achieved with transmissibilities at the higher frequencies close to that of the ideal undamped system. The negative-stiffness mechanisms can cancel the stiffness of power cables, hoses or other lines connected to payloads. This paper develops the theory, describes typical configurations and summarizes test data with prototype systems.

  10. Passive margin formation, Timor Sea, Australia

    SciTech Connect

    Hillis, R.R. )

    1990-06-01

    Recent ODP data show that sea-floor spreading began in the Argo Abyssal Plain in the earliest Cretaceous, and not the Callovian-Oxfordian as had previously been believed. These data are now consistent with the Callovian-Valanginian rifting observed on seismic records over the adjacent continental shelf (Vulcan subbasin, western Timor Sea). Tectonic subsidence plots have been constructed for well, extrapolated well, and significant off-well (seismically based) locations in the Vulcan subbasin and adjacent highs. The fully corrected plots show relatively little tectonic subsidence during the Callovian-Valanginian rift phase, even in the depocenter of the Swan Graben, where the Callovian-Valanginian interval reaches its maximum thickness. This is atypical for a passive margin basin. Assuming an extensional origin for the margin, the absence of tectonic subsidence is considered to indicate that continental rifting in the area was wet (accompanied by major volcanic activity). Recent studies have shown that extensive volcanism may occur where rift zones cut through regions of anomalously hot mantle (100-200{degree}C above normal). The addition to the crust of igneous material, the density of which has been modified by adiabatic decompression, inhibits syn-rift subsidence. A wet rifting model also has implications for the origin of the nearby marginal plateaux such as the Scott Plateau. Their relatively thick crust and lack of subsidence may be due to igneous underplating associated with wet rifting. As such the plateaux may be regarded as transitional between oceanic and continental crust. The post-Valanginian Cretaceous subsidence of the Vulcan subbasin and adjacent areas is consistent with typical post-rift thermal subsidence, the predicted exponentially decaying subsidence history for a wet rift being indistinguishable from that of a dry rift.

  11. Academic Achievement Despite Child Maltreatment: A Longitudinal Study

    ERIC Educational Resources Information Center

    Coohey, Carol; Renner, Lynette M.; Hua, Lei; Zhang, Ying J.; Whitney, Stephen D.

    2011-01-01

    Purpose: Although researchers have concluded that child maltreatment has a negative effect on children's learning and academic achievement, not all children are negatively affected by maltreatment, and some children seem to succeed academically despite being maltreated. Drawing on risk and resilience theory, we examined a broad range of potential…

  12. Unitary-process discrimination with error margin

    SciTech Connect

    Hashimoto, T.; Hayashi, A.; Horibe, M.; Hayashi, M.

    2010-06-15

    We investigate a discrimination scheme between unitary processes. By introducing a margin for the probability of an erroneous guess, this scheme interpolates the two standard discrimination schemes: minimum-error and unambiguous discrimination. We present solutions for two cases. One is the case of two unitary processes with general prior probabilities. The other is the case with a group symmetry: The processes comprise a projective representation of a finite group. In the latter case, we found that unambiguous discrimination is a kind of 'all or nothing': The maximum success probability is either 0 or 1. We also thoroughly analyze how entanglement with an auxiliary system improves discrimination performance.

  13. Deep Structures of The Angola Margin

    NASA Astrophysics Data System (ADS)

    Moulin, M.; Contrucci, I.; Olivet, J.-L.; Aslanian, D.; Géli, L.; Sibuet, J.-C.

    1 Ifremer Centre de Brest, DRO/Géosciences Marines, B.P. 70, 29280 Plouzané cedex (France) mmoulin@ifremer.fr/Fax : 33 2 98 22 45 49 2 Université de Bretagne Occidentale, Institut Universitaire Europeen de la Mer, Place Nicolas Copernic, 29280 Plouzane (France) 3 Total Fina Elf, DGEP/GSR/PN -GEOLOGIE, 2,place de la Coupole-La Defense 6, 92078 Paris la Defense Cedex Deep reflection and refraction seismic data were collected in April 2000 on the West African margin, offshore Angola, within the framework of the Zaiango Joint Project, conducted by Ifremer and Total Fina Elf Production. Vertical multichannel reflection seismic data generated by a « single-bubble » air gun array array (Avedik et al., 1993) were recorded on a 4.5 km long, digital streamer, while refraction and wide angle reflection seismic data were acquired on OBSs (Ocean Bottom Seismometers). Despite the complexity of the margin (5 s TWT of sediment, salt tectonics), the combination of seismic reflection and refraction methods results in an image and a velocity model of the ground structures below the Aptian salt layer. Three large seismic units appear in the reflection seismic section from the deep part on the margin under the base of salt. The upper seismic unit is layered with reflectors parallel to the base of the salt ; it represents unstructured sediments, filling a basin. The middle unit is seismically transparent. The lower unit is characterized by highly energetic reflectors. According to the OBS refraction data, these two units correspond to the continental crust and the base of the high energetic unit corresponds to the Moho. The margin appears to be divided in 3 domains, from east to west : i) a domain with an unthinned, 30 km thick, continental crust ; ii) a domain located between the hinge line and the foot of the continental slope, where the crust thins sharply, from 30 km to less than 7 km, this domain is underlain by an anormal layer with velocities comprising between 7,2 and 7

  14. Remote sensing of the marginal ice zone during Marginal Ice Zone Experiment (MIZEX) 83

    NASA Technical Reports Server (NTRS)

    Shuchman, R. A.; Campbell, W. J.; Burns, B. A.; Ellingsen, E.; Farrelly, B. A.; Gloersen, P.; Grenfell, T. C.; Hollinger, J.; Horn, D.; Johannessen, J. A.

    1984-01-01

    The remote sensing techniques utilized in the Marginal Ice Zone Experiment (MIZEX) to study the physical characteristics and geophysical processes of the Fram Strait Region of the Greenland Sea are described. The studies, which utilized satellites, aircraft, helicopters, and ship and ground-based remote sensors, focused on the use of microwave remote sensors. Results indicate that remote sensors can provide marginal ice zone characteristics which include ice edge and ice boundary locations, ice types and concentration, ice deformation, ice kinematics, gravity waves and swell (in the water and the ice), location of internal wave fields, location of eddies and current boundaries, surface currents and sea surface winds.

  15. Negative Entropy of Life

    NASA Astrophysics Data System (ADS)

    Goradia, Shantilal

    2015-10-01

    We modify Newtonian gravity to probabilistic quantum mechanical gravity to derive strong coupling. If this approach is valid, we should be able to extend it to the physical body (life) as follows. Using Boltzmann equation, we get the entropy of the universe (137) as if its reciprocal, the fine structure constant (ALPHA), is the hidden candidate representing the negative entropy of the universe which is indicative of the binary information as its basis (http://www.arXiv.org/pdf/physics0210040v5). Since ALPHA relates to cosmology, it must relate to molecular biology too, with the binary system as the fundamental source of information for the nucleotides of the DNA as implicit in the book by the author: ``Quantum Consciousness - The Road to Reality.'' We debate claims of anthropic principle based on the negligible variation of ALPHA and throw light on thermodynamics. We question constancy of G in multiple ways.

  16. Negative Optical Torque

    NASA Astrophysics Data System (ADS)

    Chen, Jun; Ng, Jack; Ding, Kun; Fung, Kin Hung; Lin, Zhifang; Chan, C. T.

    2014-09-01

    Light carries angular momentum, and as such it can exert torques on material objects. Applications of these opto-mechanical effects were limited initially due to their smallness in magnitude, but later becomes powerful and versatile after the invention of laser. Novel and practical approaches for harvesting light for particle rotation have since been demonstrated, where the structure is always subjected to a positive optical torque along a certain axis if the incident angular momentum has a positive projection on the same axis. We report here an interesting phenomenon of ``negative optical torque'', meaning that incoming photons carrying angular momentum rotate an object in the opposite sense. Surprisingly this can be realized quite straightforwardly in simple planar structures. Field retardation is a necessary condition and discrete rotational symmetry of material object plays an important role. The optimal conditions are explored and explained.

  17. Negative ion source

    DOEpatents

    Leung, K.N.; Ehlers, K.W.

    1982-08-06

    An ionization vessel is divided into an ionizing zone and an extraction zone by a magnetic filter. The magnetic filter prevents high-energy electrons from crossing from the ionizing zone to the extraction zone. A small positive voltage impressed on a plasma grid, located adjacent an extraction grid, positively biases the plasma in the extraction zone to thereby prevent positive ions from migrating from the ionizing zone to the extraction zone. Low-energy electrons, which would ordinarily be dragged by the positive ions into the extraction zone, are thereby prevented from being present in the extraction zone and being extracted along with negative ions by the extraction grid. Additional electrons are suppressed from the output flux using ExB drift provided by permanent magnets and the extractor grid electrical field.

  18. Negative ion source

    DOEpatents

    Leung, K.N.; Ehlers, K.W.

    1984-12-04

    An ionization vessel is divided into an ionizing zone and an extraction zone by a magnetic filter. The magnetic filter prevents high-energy electrons from crossing from the ionizing zone to the extraction zone. A small positive voltage impressed on a plasma grid, located adjacent an extraction grid, positively biases the plasma in the extraction zone to thereby prevent positive ions from migrating from the ionizing zone to the extraction zone. Low-energy electrons, which would ordinarily be dragged by the positive ions into the extraction zone, are thereby prevented from being present in the extraction zone and being extracted along with negative ions by the extraction grid. Additional electrons are suppressed from the output flux using ExB drift provided by permanent magnets and the extractor grid electrical field. 14 figs.

  19. Negative ion source

    DOEpatents

    Leung, Ka-Ngo; Ehlers, Kenneth W.

    1984-01-01

    An ionization vessel is divided into an ionizing zone and an extraction zone by a magnetic filter. The magnetic filter prevents high-energy electrons from crossing from the ionizing zone to the extraction zone. A small positive voltage impressed on a plasma grid, located adjacent an extraction grid, positively biases the plasma in the extraction zone to thereby prevent positive ions from migrating from the ionizing zone to the extraction zone. Low-energy electrons, which would ordinarily be dragged by the positive ions into the extraction zone, are thereby prevented from being present in the extraction zone and being extracted along with negative ions by the extraction grid. Additional electrons are suppressed from the output flux using ExB drift provided by permanent magnets and the extractor grid electrical field.

  20. Negative Optical Torque

    PubMed Central

    Chen, Jun; Ng, Jack; Ding, Kun; Fung, Kin Hung; Lin, Zhifang; Chan, C. T.

    2014-01-01

    Light carries angular momentum, and as such it can exert torques on material objects. Applications of these opto-mechanical effects were limited initially due to their smallness in magnitude, but later becomes powerful and versatile after the invention of laser. Novel and practical approaches for harvesting light for particle rotation have since been demonstrated, where the structure is always subjected to a positive optical torque along a certain axis if the incident angular momentum has a positive projection on the same axis. We report here an interesting phenomenon of “negative optical torque”, meaning that incoming photons carrying angular momentum rotate an object in the opposite sense. Surprisingly this can be realized quite straightforwardly in simple planar structures. Field retardation is a necessary condition and discrete rotational symmetry of material object plays an important role. The optimal conditions are explored and explained. PMID:25226863

  1. Do `negative' temperatures exist?

    NASA Astrophysics Data System (ADS)

    Lavenda, B. H.

    1999-06-01

    A modification of the second law is required for a system with a bounded density of states and not the introduction of a `negative' temperature scale. The ascending and descending branches of the entropy versus energy curve describe particle and hole states, having thermal equations of state that are given by the Fermi and logistic distributions, respectively. Conservation of energy requires isentropic states to be isothermal. The effect of adiabatically reversing the field is entirely mechanical because the only difference between the two states is their energies. The laws of large and small numbers, leading to the normal and Poisson approximations, characterize statistically the states of infinite and zero temperatures, respectively. Since the heat capacity also vanishes in the state of maximum disorder, the third law can be generalized in systems with a bounded density of states: the entropy tends to a constant as the temperature tends to either zero or infinity.

  2. Characterizing entanglement with global and marginal entropic measures

    SciTech Connect

    Adesso, Gerardo; Illuminati, Fabrizio; De Siena, Silvio

    2003-12-01

    We qualify the entanglement of arbitrary mixed states of bipartite quantum systems by comparing global and marginal mixednesses quantified by different entropic measures. For systems of two qubits we discriminate the class of maximally entangled states with fixed marginal mixednesses, and determine an analytical upper bound relating the entanglement of formation to the marginal linear entropies. This result partially generalizes to mixed states the quantification of entanglement with marginal mixednesses holding for pure states. We identify a class of entangled states that, for fixed marginals, are globally more mixed than product states when measured by the linear entropy. Such states cannot be discriminated by the majorization criterion.

  3. Achieving Magnet status.

    PubMed

    Ellis, Beckie; Gates, Judy

    2005-01-01

    Magnet has become the gold standard for nursing excellence. It is the symbol of effective and safe patient care. It evaluates components that inspire safe care, including employee satisfaction and retention, professional education, and effective interdisciplinary collaboration. In an organization whose mission focuses on excellent patient care, Banner Thunderbird Medical Center found that pursuing Magnet status was clearly the next step. In this article, we will discuss committee selection, education, team building, planning, and the discovery process that define the Magnet journey. The road to obtaining Magnet status has permitted many opportunities to celebrate our achievements. PMID:16056158

  4. Ireland's Atlantic Margin: An Investigation of the Structure of Magma-rich and Magma-poor Margins using Gravity, Magnetic and Seismic Data

    NASA Astrophysics Data System (ADS)

    Rippington, S.; Warner, J.; Rands, J.; Herbert, H.

    2014-12-01

    Ireland and its continental shelves are located in a structurally complex part of the European North Atlantic Margin. The northern part of the margin (e.g. the Rockall Basin) is considered to be magma-rich, whereas the southern part of the margin (e.g. the Porcupine Basin) is relatively magma-poor. Despite this fundamental difference, the Rockall and Porcupine regions have much in common: both have a dominant structural grain inherited from the Caledonian Orogeny, and were variably deformed by Variscan compression and multiple phases of extension and rifting. Rifting culminated in continental breakup between the North American and European plates in the Paleogene. Following continental breakup, both regions were further deformed by phases of Cenozoic compression, which have been attributed to many different causes, including the Alpine Orogeny. Hydrocarbon exploration in the region has met with limited success. This is in part due to the complex structure of the margin, and a number of persisting questions regarding the location, age, and nature of potential source and reservoir rocks, and the timing and evolution of structural traps. This study aims to re-evaluate the structural framework that underpins hydrocarbon exploration in the region. The study is based on a compilation of georeferenced maps and cross-sections, a newly merged set of marine gravity and aeromagnetic data, as well as published seismic and public domain data gravity and magnetic data, all of which are integrated in GIS. The integration of seismic and potential field data allows us to use the strengths of these different geophysical methods to investigate the crustal architecture from the seabed to the Moho. Quantitative interpretation of the crust is achieved by 2D gravity and magnetic modelling along key B.I.R.P.S seismic lines in the Rockall and Porcupine basins. These models are used to highlight similarities and differences between these areas and to suggest how the structure of the Irish

  5. Radiofrequency ablation during continuous saline infusion can extend ablation margins

    PubMed Central

    Ishikawa, Toru; Kubota, Tomoyuki; Horigome, Ryoko; Kimura, Naruhiro; Honda, Hiroki; Iwanaga, Akito; Seki, Keiichi; Honma, Terasu; Yoshida, Toshiaki

    2013-01-01

    AIM: To determine whether fluid injection during radiofrequency ablation (RFA) can increase the coagulation area. METHODS: Bovine liver (1-2 kg) was placed on an aluminum tray with a return electrode affixed to the base, and the liver was punctured by an expandable electrode. During RFA, 5% glucose; 50% glucose; or saline fluid was infused continuously at a rate of 1.0 mL/min through the infusion line connected to the infusion port. The area and volume of the thermocoagulated region of bovine liver were determined after RFA. The Joule heat generated was determined from the temporal change in output during the RFA experiment. RESULTS: No liquid infusion was 17.3 ± 1.6 mL, similar to the volume of a 3-cm diameter sphere (14.1 mL). Mean thermocoagulated volume was significantly larger with continuous infusion of saline (29.3 ± 3.3 mL) than with 5% glucose (21.4 ± 2.2 mL), 50% glucose (16.5 ± 0.9 mL) or no liquid infusion (17.3 ± 1.6 mL). The ablated volume for RFA with saline was approximately 1.7-times greater than for RFA with no liquid infusion, representing a significant difference between these two conditions. Total Joule heat generated during RFA was highest with saline, and lowest with 50% glucose. CONCLUSION: RFA with continuous saline infusion achieves a large ablation zone, and may help inhibit local recurrence by obtaining sufficient ablation margins. RFA during continuous saline infusion can extend ablation margins, and may be prevent local recurrence. PMID:23483097

  6. The Power of Perception: Mediating the Impact of Poverty on Student Achievement

    ERIC Educational Resources Information Center

    Dell'Angelo, Tabitha

    2016-01-01

    Race and class often marginalize students in impoverished urban neighborhoods, and this reality is evident in consistently low student achievement in many of the schools in these neighborhoods. This study examines how a teacher's sense of agency can help mediate the detrimental impact of poverty on student achievement. Teachers in a large…

  7. 19. Print from copy negative (original glass plate negative in ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    19. Print from copy negative (original glass plate negative in Tippecanoe County Historical Society.) Original photo dated May 7, 1893. View north, south side. - Big Four Depot, 10 South Second Street, Lafayette, Tippecanoe County, IN

  8. Hierarchical Marginal Land Assessment for Land Use Planning

    SciTech Connect

    Kang, Shujiang; Post, Wilfred M; Wang, Dali; Nichols, Dr Jeff A; Bandaru, Vara Prasad

    2013-01-01

    Marginal land provides an alternative potential for food and bioenergy production in the face of limited land resources; however, effective assessment of marginal lands is not well addressed. Concerns over environmental risks, ecosystem services and sustainability for marginal land have been widely raised. The objective of this study was to develop a hierarchical marginal land assessment framework for land use planning and management. We first identified major land functions linking production, environment, ecosystem services and economics, and then classified land resources into four categories of marginal land using suitability and limitations associated with major management goals, including physically marginal land, biologically marginal land, environmental-ecological marginal land, and economically marginal land. We tested this assessment framework in south-western Michigan, USA. Our results indicated that this marginal land assessment framework can be potentially feasible on land use planning for food and bioenergy production, and balancing multiple goals of land use management. We also compared our results with marginal land assessment from the Conservation Reserve Program (CRP) and land capability classes (LCC) that are used in the US. The hierarchical assessment framework has advantages of quantitatively reflecting land functions and multiple concerns. This provides a foundation upon which focused studies can be identified in order to improve the assessment framework by quantifying high-resolution land functions associated with environment and ecosystem services as well as their criteria are needed to improve the assessment framework.

  9. Economic Recovery of Oil Trapped at Fan Margins Using High Angle Wells and Multiple Hydraulic Fractures

    SciTech Connect

    Mike L. Laue

    1998-02-05

    This project attempts to demonstrate the effectivensss of exploiting thin-layered, low energy deposits at the distal margin of a propagating turbinite complex through u se of hydraulically fractgured horizontal of high-angle wells. TGhe combinaton of a horizontal or high-angle weoo and hydraulic fracturing will allow greater pay exposure than can be achieved with conventional vertical wells while maintaining vertical communication between thin interbedded layers and the wellbore.

  10. Economic Recovery of Oil Trapped at Fan Margins Using High Angle Wells and Multiple Hydraulic Fractures

    SciTech Connect

    Mike L. Laue

    1997-05-08

    This project attempts to demonstrate the effectiveness of exploiting thin-layered, low-energy deposits at the distal margin of a propagating turbidite complex through the use of hydraulically-fractured horizontal or high-angle wells. The combination of a horizontal or high-angled well and hydraulic fracturing will allow greater pay exposure than can be achieved with conventional vertical wells while maintaining vertical communication between thininterbedded layers and the well bore.

  11. Economic Recovery of Oil Trapped at Fan Margins Using High Angle Wells and Multiple Hydraulic Fractures

    SciTech Connect

    Laue, M.L.

    1999-11-01

    This project attempts to demonstrate the effectiveness of exploiting thin-layered, low-energy deposits at the distal margin of a prograding turbidite complex through the use of hydraulically fractured horizontal or high-angle wells. The combination of a horizontal or high-angle well and hydraulic fracturing will allow greater pay exposure than can be achieved with conventional vertical wells while maintaining vertical communication between thin interbedded layers and the wellbore.

  12. Detailed surveys of offshore Peru margin

    SciTech Connect

    Hussong, D.M.; Taylor, B.; Kulm, L.D.; Hilde, T.W.C.

    1986-07-01

    The complex and highly variable structure of the submarine continental margin of central Peru is revealed by geophysical surveys and geologic sampling completed in 1985. The surveys were conducted in preparation for deep scientific drilling to be undertaken by the Ocean Drilling Program in November-December 1986. More than 11,000 km/sup 2/ of sea floor were mapped using the SeaMARC II side-scan sonar and bathymetry system; 1500 km of multichannel seismic reflection profiles and 4000 km of single-channel seismic data were shot; and many coring, dredging, and heat-flow stations were obtained. The data permit construction of detailed three-dimensional geologic maps of the region. These maps show that the ancient metamorphic rocks of South America extend close to the trench axis and apparently have undergone a history of truncation and subsidence related to the subduction of the Nazca oceanic plate. Adjacent segments of the Peru forearc have dramatically different structure and appear to have had differing tectonic histories. The margin is disrupted by extensive (primarily tensional) faulting; the larger faults extend perpendicular to the strike of the trench and often serve as conduits for diapirs and mud volcanoes. Living chemosynthetic clams were dredged from 3800-m depth along one of these fault trends, suggesting that active fluid venting occurs at depth on the continental wall of the Peru Trench.

  13. On recent developments in marginal separation theory

    PubMed Central

    Braun, S.; Scheichl, S.

    2014-01-01

    Thin aerofoils are prone to localized flow separation at their leading edge if subjected to moderate angles of attack α. Although ‘laminar separation bubbles’ at first do not significantly alter the aerofoil performance, they tend to ‘burst’ if α is increased further or if perturbations acting upon the flow reach a certain intensity. This then either leads to global flow separation (stall) or triggers the laminar–turbulent transition process within the boundary layer flow. This paper addresses the asymptotic analysis of the early stages of the latter phenomenon in the limit as the characteristic Reynolds number , commonly referred to as marginal separation theory. A new approach based on the adjoint operator method is presented that enables the fundamental similarity laws of marginal separation theory to be derived and the analysis to be extended to higher order. Special emphasis is placed on the breakdown of the flow description, i.e. the formation of finite-time singularities (a manifestation of the bursting process), and on its resolution being based on asymptotic arguments. The passage to the subsequent triple-deck stage is described in detail, which is a prerequisite for carrying out a future numerical treatment of this stage in a proper way. Moreover, a composite asymptotic model is developed in order for the inherent ill-posedness of the Cauchy problems associated with the current flow description to be resolved. PMID:24936013

  14. Review and Assessment of JPL's Thermal Margins

    NASA Technical Reports Server (NTRS)

    Siebes, G.; Kingery, C.; Farguson, C.; White, M.; Blakely, M.; Nunes, J.; Avila, A.; Man, K.; Hoffman, A.; Forgrave, J.

    2012-01-01

    JPL has captured its experience from over four decades of robotic space exploration into a set of design rules. These rules have gradually changed into explicit requirements and are now formally implemented and verified. Over an extended period of time, the initial understanding of intent and rationale for these rules has faded and rules are now frequently applied without further consideration. In the meantime, mission classes and their associated risk postures have evolved, coupled with resource constraints and growing design diversity, bringing into question the current "one size fits all" thermal margin approach. This paper offers a systematic review of the heat flow path from an electronic junction to the eventual heat rejection to space. This includes the identification of different regimes along this path and the associated requirements. The work resulted in a renewed understanding of the intent behind JPL requirements for hot thermal margins and a framework for relevant considerations, which in turn enables better decision making when a deviation to these requirements is considered.

  15. Financial incentives for marginal oil and gas production

    SciTech Connect

    Terzian, G.A.; Enright, J.M.; Brashear, J.P.

    1995-12-31

    Congress and the Administration are considering Federal tax incentives to improve the economics of marginal oil and gas wells. The effectiveness of these will depend on the specific provisions of the incentive, primarily whether they can be used by the large percentage of marginal well operators in AMT or without taxable income. Comprehensive assessment of Federal marginal well incentives requires a methodology that accounts for the diversity of marginal production operations. This paper presents a marginal well database, model, and methodology designed specifically to assess the costs and benefits of Federal tax incentives for marginal wells. Selected results are presented, along with general conclusions about Federal marginal well tax incentives based on numerous analyses.

  16. A computational model for estimating tumor margins in complementary tactile and 3D ultrasound images

    NASA Astrophysics Data System (ADS)

    Shamsil, Arefin; Escoto, Abelardo; Naish, Michael D.; Patel, Rajni V.

    2016-03-01

    Conventional surgical methods are effective for treating lung tumors; however, they impose high trauma and pain to patients. Minimally invasive surgery is a safer alternative as smaller incisions are required to reach the lung; however, it is challenging due to inadequate intraoperative tumor localization. To address this issue, a mechatronic palpation device was developed that incorporates tactile and ultrasound sensors capable of acquiring surface and cross-sectional images of palpated tissue. Initial work focused on tactile image segmentation and fusion of position-tracked tactile images, resulting in a reconstruction of the palpated surface to compute the spatial locations of underlying tumors. This paper presents a computational model capable of analyzing orthogonally-paired tactile and ultrasound images to compute the surface circumference and depth margins of a tumor. The framework also integrates an error compensation technique and an algebraic model to align all of the image pairs and to estimate the tumor depths within the tracked thickness of a palpated tissue. For validation, an ex vivo experimental study was conducted involving the complete palpation of 11 porcine liver tissues injected with iodine-agar tumors of varying sizes and shapes. The resulting tactile and ultrasound images were then processed using the proposed model to compute the tumor margins and compare them to fluoroscopy based physical measurements. The results show a good negative correlation (r = -0.783, p = 0.004) between the tumor surface margins and a good positive correlation (r = 0.743, p = 0.009) between the tumor depth margins.

  17. Interactions of CUP-SHAPED COTYLEDON and SPATULA Genes Control Carpel Margin Development in Arabidopsis thaliana

    PubMed Central

    Nahar, Most. Altaf-Un; Ishida, Tetsuya; Smyth, David R; Tasaka, Masao; Aida, Mitsuhiro

    2012-01-01

    A characteristic feature of flowering plants is the fusion of carpels, which results in the formation of an enclosed gynoecium. In Arabidopsis thaliana, the gynoecium is formed by the fusion of two carpels along their margins, which also act as a meristematic site for the formation of internal structures such as ovules, the septum and transmitting tract. How gene interactions coordinate the fusion and differentiation of the marginal structures during gynoecium development is largely unknown. It was previously shown that the SPATULA (SPT) gene is required for carpel fusion, whereas overexpression of the CUP-SHAPED COTYLEDON genes CUC1 and CUC2 prevents it. Here we provide evidence that SPT promotes carpel fusion in the apical gynoecium partly through the negative regulation of CUC1 and CUC2 expression. In spt, transcripts of both CUC genes accumulated ectopically, and addition of cuc1 and cuc2 mutations to spt suppressed the split phenotype of carpels specifically along their lateral margins. In the basal gynoecium, on the other hand, all three genes promoted the formation of margin-derived structures, as revealed by the synergistic interactions of spt with each of the cuc mutations. Our results suggest that differential interactions among SPT, CUC1 and CUC2 direct the formation of domain-specific structures of the Arabidopsis gynoecium. PMID:22514090

  18. Negative Expertise: Comparing Differently Tenured Elder Care Nurses' Negative Knowledge

    ERIC Educational Resources Information Center

    Gartmeier, Martin; Lehtinen, Erno; Gruber, Hans; Heid, Helmut

    2011-01-01

    Negative expertise is conceptualised as the professional's ability to avoid errors during practice due to certain cognitive agencies. In this study, negative knowledge (i.e. knowledge about what is wrong in a certain context and situation) is conceptualised as one such agency. This study compares and investigates the negative knowledge of elder…

  19. Investigating Continental Margins: An Activity to Help Students Better Understand the Continental Margins of North America

    ERIC Educational Resources Information Center

    Poli, Maria-Serena; Capodivacca, Marco

    2011-01-01

    Continental margins are an important part of the ocean floor. They separate the land above sea level from the deep ocean basins below and occupy about 11% of Earth's surface. They are also economically important, as they harbor both mineral resources and some of the most valuable fisheries in the world. In this article students investigate North…

  20. Singular perturbation margin and generalised gain margin for nonlinear time-invariant systems

    NASA Astrophysics Data System (ADS)

    Yang, Xiaojing; Zhu, J. Jim

    2016-03-01

    In this paper, singular perturbation margin (SPM) and generalised gain margin (GGM) are proposed as the classical phase margin and gain margin like stability metrics for nonlinear systems established from the view of the singular perturbation and the regular perturbation, respectively. The problem of SPM and GGM assessment of a nonlinear nominal system is formulated. The SPM and GGM formulations are provided as the functions of radius of attraction (ROA), which is introduced as a conservative measure of the domain of attraction (DOA). Furthermore, the ROA constrained SPM and GGM analysis are processed through two stages: (1) the SPM and GGM assessment for nonlinear systems at the equilibrium point, based on the SPM and GGM equilibrium theorems, including time-invariant and time-varying cases (Theorem 5.3, Theorem 5.2, Theorem 5.4 and Theorem 5.5); (2) the establishment of the relationship between the SPM or GGM and the ROA for nonlinear time-invariant systems through the construction of the Lyapunov function for the singularly perturbed model (Theorem 6.1 and Section 6.2.3).

  1. Talking (and Not Talking) about Race, Social Class and Dis/Ability: Working Margin to Margin

    ERIC Educational Resources Information Center

    Ferri, Beth A.; Connor, David J.

    2014-01-01

    In this article we examine some of the omnipresent yet unacknowledged discourses of social and economic disadvantage and dis/ability within schools in the US. First, we document ways that social class, race, and dis/ability function within schools to further disadvantage and exclude already marginalized students. Next, we show how particular ways…

  2. Negative obstacle detection by thermal signature

    NASA Technical Reports Server (NTRS)

    Matthies, Larry; Rankin, A.

    2003-01-01

    Detecting negative obstacles (ditches, potholes, and other depressions) is one of the most difficult problems in perception for autonomous, off-road navigation. Past work has largely relied on range imagery, because that is based on the geometry of the obstacle, is largely insensitive to illumination variables, and because there have not been other reliable alternatives. However, the visible aspect of negative obstacles shrinks rapidly with range, making them impossible to detect in time to avoid them at high speed. To relive this problem, we show that the interiors of negative obstacles generally remain warmer than the surrounding terrain throughout the night, making thermal signature a stable property for night-time negative obstacle detection. Experimental results to date have achieved detection distances 45% greater by using thermal signature than by using range data alone. Thermal signature is the first known observable with potential to reveal a deep negative obstacle without actually seeing far into it. Modeling solar illumination has potential to extend the usefulness of thermal signature through daylight hours.

  3. Partitioning of deformation along a reactivated rifted margin: example of the northern Ligurian margin.

    NASA Astrophysics Data System (ADS)

    Sage, Françoise; Beslier, Marie-Odile; Gaullier, Virginie; Larroque, Christophe; Dessa, Jean-Xavier; Mercier de Lepinay, Bernard; Corradi, Nicola; Migeon, Sébastien; Katz, Hélène; Ruiz Constan, Ana

    2013-04-01

    The northern Ligurian margin, of Oligo-Miocene age, is currently undergoing compression related to microplate motions and/or to gravity spreading of the Alpine chain located immediately north of it. Active thrust faults and folds have previously been identified below the margin, together with a global uplift of the continental edge, since at least the Messinian. The seismicity that goes with the present-day margin contraction (e.g. Mw 6.9, 1887/02/23) extends to the axis of the adjacent oceanic basin (e.g. ML 6.0, 1963/07/19; ML 5.4, 2011/07/07). However, we do not know of any recent or active crustal contractional structure within this oceanic domain. In this study, we use new 12-channel high-resolution seismic data (FABLES seismic cruise, 2012, R/V Tethys II) in order to image the sedimentary cover of the Ligurian oceanic basin, up to ~3km below the seabed, including the Plio-Quaternary and the Messinian sediment down to the bottom of the Messinian salt layer. Because the Messinian event is well dated (5.96-5.32 Ma) and well identified in the seismic data, it forms a clear marker that we use to characterize the recent deformation related to both mobile salt motion and crustal tectonics. About 50 km south of the margin offshore of Italy, we identify huge and complex salt walls that elongate SW-NE. Such salt walls, which cannot be explained by salt tectonics only, are interpreted as evidence of deep-seated crustal deformation. They form en echelon structures that are well expressed in the seabed morphology, and do not correspond to any significant vertical throw at the base of the salt layer. This suggests that within the deep basin, mainly strike-slip faulting accommodates long-term crustal deformation. It thus offers a contrast with the margin where deformation is mainly marked by shortening and reverse faulting, with vertical throws of several hundred meters. This discrepancy in the tectonic styles between the margin and the adjacent oceanic basin suggests some

  4. Adolescent Health Behavior, Contentment in School, and Academic Achievement

    ERIC Educational Resources Information Center

    Kristjansson, Alfgeir Logi; Sigfusdottir, Inga Dora; Allegrante, John P.; Helgason, Asgeir R.

    2009-01-01

    Objectives: To examine the association between health behavior indicators, school contentment, and academic achievement. Methods: Structural equation modeling with 5810 adolescents. Results: Our model explained 36% of the variance in academic achievement and 24% in school contentment. BMI and sedentary lifestyle were negatively related to school…

  5. Parenting Styles and Academic Achievement: A Cross-Cultural Study.

    ERIC Educational Resources Information Center

    Leung, Kwok; Lau, Sing; Lam, Wai-Lim

    1998-01-01

    Investigated relationships between parenting style and adolescents' academic achievement in Hong Kong, United States, and Australia. Found cultural differences in general and academic authoritarianism and general authoritativeness. Academic achievement was negatively related to academic authoritarianism and was positively related to general…

  6. Does Recreational Computer Use Affect High School Achievement?

    ERIC Educational Resources Information Center

    Bowers, Alex J.; Berland, Matthew

    2013-01-01

    Historically, the relationship between student academic achievement and use of computers for fun and video gaming has been described from a multitude of perspectives, from positive, to negative, to neutral. However, recent research has indicated that computer use and video gaming may be positively associated with achievement, yet these studies…

  7. Recognizing outstanding achievements

    NASA Astrophysics Data System (ADS)

    Speiss, Fred

    One function of any professional society is to provide an objective, informed means for recognizing outstanding achievements in its field. In AGU's Ocean Sciences section we have a variety of means for carrying out this duty. They include recognition of outstanding student presentations at our meetings, dedication of special sessions, nomination of individuals to be fellows of the Union, invitations to present Sverdrup lectures, and recommendations for Macelwane Medals, the Ocean Sciences Award, and the Ewing Medal.Since the decision to bestow these awards requires initiative and judgement by members of our section in addition to a deserving individual, it seems appropriate to review the selection process for each and to urge you to identify those deserving of recognition.

  8. Achieving closure at Fernald

    SciTech Connect

    Bradburne, John; Patton, Tisha C.

    2001-02-25

    When Fluor Fernald took over the management of the Fernald Environmental Management Project in 1992, the estimated closure date of the site was more than 25 years into the future. Fluor Fernald, in conjunction with DOE-Fernald, introduced the Accelerated Cleanup Plan, which was designed to substantially shorten that schedule and save taxpayers more than $3 billion. The management of Fluor Fernald believes there are three fundamental concerns that must be addressed by any contractor hoping to achieve closure of a site within the DOE complex. They are relationship management, resource management and contract management. Relationship management refers to the interaction between the site and local residents, regulators, union leadership, the workforce at large, the media, and any other interested stakeholder groups. Resource management is of course related to the effective administration of the site knowledge base and the skills of the workforce, the attraction and retention of qualified a nd competent technical personnel, and the best recognition and use of appropriate new technologies. Perhaps most importantly, resource management must also include a plan for survival in a flat-funding environment. Lastly, creative and disciplined contract management will be essential to effecting the closure of any DOE site. Fluor Fernald, together with DOE-Fernald, is breaking new ground in the closure arena, and ''business as usual'' has become a thing of the past. How Fluor Fernald has managed its work at the site over the last eight years, and how it will manage the new site closure contract in the future, will be an integral part of achieving successful closure at Fernald.

  9. Coagulase-Negative Staphylococci

    PubMed Central

    Heilmann, Christine; Peters, Georg

    2014-01-01

    SUMMARY The definition of the heterogeneous group of coagulase-negative staphylococci (CoNS) is still based on diagnostic procedures that fulfill the clinical need to differentiate between Staphylococcus aureus and those staphylococci classified historically as being less or nonpathogenic. Due to patient- and procedure-related changes, CoNS now represent one of the major nosocomial pathogens, with S. epidermidis and S. haemolyticus being the most significant species. They account substantially for foreign body-related infections and infections in preterm newborns. While S. saprophyticus has been associated with acute urethritis, S. lugdunensis has a unique status, in some aspects resembling S. aureus in causing infectious endocarditis. In addition to CoNS found as food-associated saprophytes, many other CoNS species colonize the skin and mucous membranes of humans and animals and are less frequently involved in clinically manifested infections. This blurred gradation in terms of pathogenicity is reflected by species- and strain-specific virulence factors and the development of different host-defending strategies. Clearly, CoNS possess fewer virulence properties than S. aureus, with a respectively different disease spectrum. In this regard, host susceptibility is much more important. Therapeutically, CoNS are challenging due to the large proportion of methicillin-resistant strains and increasing numbers of isolates with less susceptibility to glycopeptides. PMID:25278577

  10. Improved negative ion source

    DOEpatents

    Delmore, J.E.

    1984-05-01

    A method and apparatus for providing a negative ion source accelerates electrons away from a hot filament electron emitter into a region of crossed electric and magnetic fields arranged in a magnetron configuration. During a portion of the resulting cycloidal path, the electron velocity is reduced below its initial value. The electron accelerates as it leaves the surface at a rate of only slightly less than if there were no magnetic field, thereby preventing a charge buildup at the surface of the emitter. As the electron traverses the cycloid, it is decelerated during the second, third, and fourth quadrants, then reaccelerated as it approaches the end of the fourth quadrant to regain its original velocity. The minimum velocity occurs during the fourth quadrant, and corresponds to an electron temperature of 200 to 500/sup 0/C for the electric and magnetic fields commonly encountered in the ion sources of magnetic sector mass spectrometers. An ion source using the above-described thermalized electrons is also disclosed.

  11. Coagulase-negative staphylococci.

    PubMed

    Becker, Karsten; Heilmann, Christine; Peters, Georg

    2014-10-01

    The definition of the heterogeneous group of coagulase-negative staphylococci (CoNS) is still based on diagnostic procedures that fulfill the clinical need to differentiate between Staphylococcus aureus and those staphylococci classified historically as being less or nonpathogenic. Due to patient- and procedure-related changes, CoNS now represent one of the major nosocomial pathogens, with S. epidermidis and S. haemolyticus being the most significant species. They account substantially for foreign body-related infections and infections in preterm newborns. While S. saprophyticus has been associated with acute urethritis, S. lugdunensis has a unique status, in some aspects resembling S. aureus in causing infectious endocarditis. In addition to CoNS found as food-associated saprophytes, many other CoNS species colonize the skin and mucous membranes of humans and animals and are less frequently involved in clinically manifested infections. This blurred gradation in terms of pathogenicity is reflected by species- and strain-specific virulence factors and the development of different host-defending strategies. Clearly, CoNS possess fewer virulence properties than S. aureus, with a respectively different disease spectrum. In this regard, host susceptibility is much more important. Therapeutically, CoNS are challenging due to the large proportion of methicillin-resistant strains and increasing numbers of isolates with less susceptibility to glycopeptides. PMID:25278577

  12. Engine Development Design Margins Briefing Charts

    NASA Technical Reports Server (NTRS)

    Bentz, Chuck

    2006-01-01

    New engines experience durability problems after entering service. The most prevalent and costly is the hot section, particularly the high-pressure turbine. The origin of durability problems can be traced back to: 1) the basic aero-mechanical design systems, assumptions, and design margins used by the engine designers, 2) the available materials systems, and 3) to a large extent, aggressive marketing in a highly competitive environment that pushes engine components beyond the demonstrated capability of the basic technology available for the hardware designs. Unfortunately the user must operate the engine in the service environment in order to learn the actual thrust loading and the time at max effort take-off conditions used in service are needed to determine the hot section life. Several hundred thousand hours of operational service will be required before the demonstrated reliability of a fleet of engines or the design deficiencies of the engine hot section parts can be determined. Also, it may take three to four engine shop visits for heavy maintenance on the gas path hardware to establish cost effective build standards. Spare parts drive the oerator's engine maintenance costs but spare parts also makes lots of money for the engine manufacturer during the service life of an engine. Unless competition prevails for follow-on engine buys, there is really no motivation for an OEM to spend internal money to improve parts durability and reduce earnings derived from a lucrative spare parts business. If the hot section life is below design goals or promised values, the OEM migh argue that the engine is being operated beyond its basic design intent. On the other hand, the airframer and the operator will continue to remind the OEM that his engine was selected based on a lot of promises to deliver spec thrust with little impact on engine service life if higher thrust is used intermittently. In the end, a standoff prevails and nothing gets fixed. This briefing will propose

  13. Negative Pressure Wound Therapy

    PubMed Central

    2006-01-01

    Executive Summary Objective This review was conducted to assess the effectiveness of negative pressure wound therapy. Clinical Need: Target Population and Condition Many wounds are difficult to heal, despite medical and nursing care. They may result from complications of an underlying disease, like diabetes; or from surgery, constant pressure, trauma, or burns. Chronic wounds are more often found in elderly people and in those with immunologic or chronic diseases. Chronic wounds may lead to impaired quality of life and functioning, to amputation, or even to death. The prevalence of chronic ulcers is difficult to ascertain. It varies by condition and complications due to the condition that caused the ulcer. There are, however, some data on condition-specific prevalence rates; for example, of patients with diabetes, 15% are thought to have foot ulcers at some time during their lives. The approximate community care cost of treating leg ulcers in Canada, without reference to cause, has been estimated at upward of $100 million per year. Surgically created wounds can also become chronic, especially if they become infected. For example, the reported incidence of sternal wound infections after median sternotomy is 1% to 5%. Abdominal surgery also creates large open wounds. Because it is sometimes necessary to leave these wounds open and allow them to heal on their own (secondary intention), some may become infected and be difficult to heal. Yet, little is known about the wound healing process, and this makes treating wounds challenging. Many types of interventions are used to treat wounds. Current best practice for the treatment of ulcers and other chronic wounds includes debridement (the removal of dead or contaminated tissue), which can be surgical, mechanical, or chemical; bacterial balance; and moisture balance. Treating the cause, ensuring good nutrition, and preventing primary infection also help wounds to heal. Saline or wet-to-moist dressings are reported as

  14. Sound Absorption of a 2DOF Resonant Liner with Negative Bias Flow

    NASA Technical Reports Server (NTRS)

    Ahuja, K. K.; Cataldi, P.; Gaeta, R. J., Jr.; Jones, Mike (Technical Monitor)

    2000-01-01

    This report describes an experimental study conducted to determine the effect of negative bias flow on the sound absorption of a two degree-of-freedom liner. The backwall for the liner was designed to act as a double-Helmholtz resonator so as to act as a hard wall at all frequencies except at its resonant frequencies. All normal incident impedance data presented herein was acquired in an impedance tube. The effect of bias flow is investigated for a buried septum porosity of 2% and 19.5% for bias flow orifice mach numbers up to 03 11. As a porous backwall is needed for the flow to pass through, the effect of bias flow on this backwall all had to be evaluated first. The bias flow appears to modify the resistance and reactance of the backwall alone at lower frequencies up to about 2 kHz, with marginal effects at higher frequencies. Absorption coefficients close to unity are achieved for a frequency range of 500-4000 Hz for the overall liner for a septum porosity of 2% and orifice mach number of 0.128. Insertion loss tests performed in a flow duct facility for grazing flow Mach numbers up to 0.2 and septum mach numbers up to 0.15 showed that negative bias flow can increase insertion loss by as much as 10 dB at frequencies in the range of 500 - 1400 Hz compared to no grazing flow. The effectiveness of the negative bias flow is diminished as the grazing flow velocity is increased.

  15. Conservatives, liberals, and "the negative".

    PubMed

    Charney, Evan

    2014-06-01

    The authors connect conservatism with aversion to negativity via the tendentious use of the language of threats to characterize conservatism, but not liberalism. Their reliance upon an objective conception of the negative ignores the fact that much of the disagreement between liberals and conservatives is over whether or not one and the same state of affairs is negative or positive. PMID:24970432

  16. Negativity bias and basic values.

    PubMed

    Schwartz, Shalom H

    2014-06-01

    Basic values explain more variance in political attitudes and preferences than other personality and sociodemographic variables. The values most relevant to the political domain are those likely to reflect the degree of negativity bias. Value conflicts that represent negativity bias clarify differences between what worries conservatives and liberals and suggest that relations between ideology and negativity bias are linear. PMID:24970450

  17. Prediction and diagnosis of clinical outcomes affecting restoration margins.

    PubMed

    Dennison, J B; Sarrett, D C

    2012-04-01

    The longevity of dental restorations is largely dependent on the continuity at the interface between the restorative material and adjacent tooth structure (the restoration margin). Clinical decisions on restoration repair or replacement are usually based upon the weakest point along that margin interface. Physical properties of a restorative material, such as polymerisation shrinkage, water sorption, solubility, elastic modulus and shear strength, all have an effect on stress distribution and can significantly affect margin integrity. This review will focus on two aspects of margin deterioration in the oral environment: the in vitro testing of margin seal using emersion techniques to simulate the oral environment and to predict clinical margin failure and the relationship between clinically observable microleakage and secondary caries. The many variables associated with in vitro testing of marginal leakage and the interpretation of the data are presented in detail. The most recent studies of marginal leakage mirror earlier methodology and lack validity and reliability. The lack of standardised testing procedures makes it impossible to compare studies or to predict the clinical performance of adhesive materials. Continual repeated in vitro studies contribute little to the science in this area. Clinical evidence is cited to refute earlier conclusions that clinical microleakage (penetrating margin discoloration) leads to caries development and is an indication for restoration replacement. Margin defects, without visible evidence of soft dentin on the wall or base of the defect, should be monitored, repaired or resealed, in lieu of total restoration replacement. PMID:22066463

  18. Achievement Goals and Achievement Emotions: A Meta-Analysis

    ERIC Educational Resources Information Center

    Huang, Chiungjung

    2011-01-01

    This meta-analysis synthesized 93 independent samples (N = 30,003) in 77 studies that reported in 78 articles examining correlations between achievement goals and achievement emotions. Achievement goals were meaningfully associated with different achievement emotions. The correlations of mastery and mastery approach goals with positive achievement…

  19. Overlapping illusions by transformation optics without any negative refraction material

    PubMed Central

    Sun, Fei; He, Sailing

    2016-01-01

    A novel method to achieve an overlapping illusion without any negative refraction index material is introduced with the help of the optic-null medium (ONM) designed by an extremely stretching spatial transformation. Unlike the previous methods to achieve such an optical illusion by transformation optics (TO), our method can achieve a power combination and reshape the radiation pattern at the same time. Unlike the overlapping illusion with some negative refraction index material, our method is not sensitive to the loss of the materials. Other advantages over existing methods are discussed. Numerical simulations are given to verify the performance of the proposed devices. PMID:26751285

  20. MARGINAL EXPENSE OIL WELL WIRELESS SURVEILLANCE MEOWS

    SciTech Connect

    Mason M. Medizade; John R. Ridgely; Donald G. Nelson

    2004-11-01

    A marginal expense oil well wireless surveillance system to monitor system performance and production from rod-pumped wells in real time from wells operated by Vaquero Energy in the Edison Field, Main Area of Kern County in California has been successfully designed and field tested. The surveillance system includes a proprietary flow sensor, a programmable transmitting unit, a base receiver and receiving antenna, and a base station computer equipped with software to interpret the data. First, the system design is presented. Second, field data obtained from three wells is shown. Results of the study show that an effective, cost competitive, real-time wireless surveillance system can be introduced to oil fields across the United States and the world.

  1. JGR and marginal ice zone processes

    NASA Astrophysics Data System (ADS)

    As a follow-up to the special sessions on marginal ice zone (MIZ) processes at the AGU 1981 Fall Meeting in San Francisco and to sessions scheduled for the upcoming AGU/ASLO Meeting in San Antonio, a collection of papers on MIZ research is planned for the Journal of Geophysical Research.Tentative titles for manuscripts should be sent as soon as possible to Robin D. Muench, Coordinator JGR/MIZ Issue, SAI/Northwest, 13400B Northrup Way #36, Bellevue, WA 98005. Finished manuscripts, due April 1, 1982, should be sent directly to A.D. Kirwan, Jr., coeditor of JGR, Oceans and Atmospheres, Department of Marine Science, University of South Florida, 140 Seventh Ave. South, St. Petersburg, FL 33701. Authors are requested to specify that manuscripts are for the special MIZ issue.

  2. HIDUTYDRV Code, A Fuel Product Margin Tool

    SciTech Connect

    Krammen, Michael A.; Karoutas, Zeses E.; Grill, Steven F.; Sutharshan, Balendra

    2007-07-01

    HIDUTYDRV is a computer code currently used in core design to model the best estimate steady-state fuel rod corrosion performance for Westinghouse's CE-design 14x14 and 16x16 fuel. The fuel rod oxide thickness, sub-cooled nucleate boiling (referred to as mass evaporation or steaming), and fuel duty indices can be predicted for individual rods or up to every fuel rod in the quarter core at every nuclear fuel management depletion time-step as a function of axial elevation within the core. Best estimate operating margins for fuel components whose performance depends on the local power and thermal hydraulic conditions are candidates for analysis with HIDUTYDRV. HIDUTYDRV development will focus on fuel component parameters associated with known leakers for addressing INPO goals to eliminate fuel leakers by 2010. (authors)

  3. The intensive margin of technology adoption--Experimental evidence on improved cooking stoves in rural Senegal.

    PubMed

    Bensch, Gunther; Peters, Jörg

    2015-07-01

    Today, almost 3 billion people in developing countries rely on biomass as primary cooking fuel, with profound negative implications for their well-being. Improved biomass cooking stoves are alleged to counteract these adverse effects. This paper evaluates take-up and impacts of low-cost improved stoves through a randomized controlled trial. The randomized stove is primarily designed to curb firewood consumption, but not smoke emissions. Nonetheless, we find considerable effects not only on firewood consumption, but also on smoke exposure and, consequently, smoke-related disease symptoms. The reduced smoke exposure results from behavioural changes in terms of increased outside cooking and a reduction in cooking time. We conclude that in order to assess the effectiveness of a technology-oriented intervention, it is critical to not only account for the incidence of technology adoption - the extensive margin - but also for the way the new technology is used - the intensive margin. PMID:25841214

  4. Localized Deformation along an Inverted Rifted Margin: Example of the Northern Ligurian Margin, Western Mediterranean

    NASA Astrophysics Data System (ADS)

    SAGE, F.; Beslier, M.; Mercier De Lepinay, B. F.; Béthoux, N.; Gaullier, V.; Larroque, C.; Corradi, N.; Schenini, L.; Dessa, J.; Bigot, A.; Migeon, S.; Ruiz-Constán, A.

    2013-12-01

    Along rifted margins, continental edges are heterogeneous systems that juxtapose lithospheres with different nature, mechanical behavior and structural inheritance. In this study, we focus on the northern Ligurian margin to examine how such complex systems might deform when they are submitted to a compressive stress field. The northern Ligurian margin, of Oligo-Miocene age, has been undergoing contraction over at least the past ~ 6 Ma. Active thrust faults and folds responsible for the regional uplift of the continental edge have previously been identified below the margin. Although seismicity extends as far as the axis of the basin, no recent or active crustal compressional structure has been identified so far in the oceanic domain. We used new 12-channel high-resolution seismic data (FABLES cruise, 2012) and other seismic reflexion lines from the last decades to image the sedimentary cover in the Ligurian oceanic basin, down to the bottom of the Messinian salt layer ~ 3 km below the seafloor. Because the Messinian event is well dated over the Mediterranean (5.96-5.32 Ma) and well identified in the seismic data, it forms a clear marker characterizing the recent deformation related to both salt and crustal tectonics. Noticeable deformation within the oceanic domain is restricted to large, SW-NE elongated salt walls located 10 to 40 km from the margin toe, over a 70-km length. The salt walls have a specific structure and arrangement that cannot result from salt tectonics only. We thus interpret them as resulting from combined deep-seated crustal and thin-skinned deformations. However, although the salt walls are well expressed in the seafloor morphology, their seismic images do not reveal any significant vertical throw across their trace, and they gradually disappear toward the SW. We thus interpret the salt walls as strike-slip structures with possibly very moderate compression. Overall, the post-Messinian deformation taken along these features is likely moderate

  5. Meaning-Making and Motivation in Urban Zones of Marginalization: Mapping the Ecocultural Context of Educational Goals

    ERIC Educational Resources Information Center

    Eksner, H. Julia

    2015-01-01

    This article explores how achievement motivation is framed by the larger context of the devaluation of educational capital that is currently underway in urban centers in Europe. The article elucidates the shared cultural meaning working-class German Turkish youths living in urban marginalized zones in Berlin, Germany create about the decreasing…

  6. Fabrication of isolated gates by negative-tone process and resolution enhancement technology

    NASA Astrophysics Data System (ADS)

    Morikawa, Ryoko; Uchida, Noboru; Watanabe, Minoru; Yabe, Sachiko; Machida, Satoshi; Taguchi, Takashi

    2000-07-01

    Interesting characteristics of a negative-tone process have been reported: enlargement of photolithographic margins of isolated line, reduction of optical proximity effect, greater dry etching selectivity. A possibility of fabrication of isolated gates of 0.13micrometers class logic device by the combination of negative-tone process and resolution enhancement technology (RET), was investigated in the KrF lithography. Photolithographic margins of 0.13micrometers isolated line were evaluated by simulation and experiment as well. Parameters are mask type, the transparency of attenuated PSM, mask-pattern size, and coherence factor. The condition defined by the optimal combination of attenuated PSM, mask-pattern size, and coherence factor. The condition defined by the optimal combination of attenuated PSM and a small coherence factor value at NA equals 0.60 increased the photolithographic margins of 0.13 micrometers isolated line. The margins evaluate under the optimal condition exceeded either of the values obtained in the negative-tone process without RET, and in positive-tone process with attenuated PSM and annular illumination. The effect of residue could be neglected in the isolate line under the optimal condition. The common window of 0.13micrometers isolate line and 0.18micrometers L/S, and that of 0.13micrometers isolated line and 0.20micrometers L/S, both increased under the optimal condition. The margins of 0.13micrometers isolated line further increased when NA was 0.68.

  7. Entrepreneur achievement. Liaoning province.

    PubMed

    Zhao, R

    1994-03-01

    This paper reports the successful entrepreneurial endeavors of members of a 20-person women's group in Liaoning Province, China. Jing Yuhong, a member of the Family Planning Association at Shileizi Village, Dalian City, provided the basis for their achievements by first building an entertainment/study room in her home to encourage married women to learn family planning. Once stocked with books, magazines, pamphlets, and other materials on family planning and agricultural technology, dozens of married women in the neighborhood flocked voluntarily to the room. Yuhong also set out to give these women a way to earn their own income as a means of helping then gain greater equality with their husbands and exert greater control over their personal reproductive and social lives. She gave a section of her farming land to the women's group, loaned approximately US$5200 to group members to help them generate income from small business initiatives, built a livestock shed in her garden for the group to raise marmots, and erected an awning behind her house under which mushrooms could be grown. The investment yielded $12,000 in the first year, allowing each woman to keep more than $520 in dividends. Members then soon began going to fairs in the capital and other places to learn about the outside world, and have successfully ventured out on their own to generate individual incomes. Ten out of twenty women engaged in these income-generating activities asked for and got the one-child certificate. PMID:12287775

  8. Formation and evolution of magma-poor margins, an example of the West Iberia margin

    NASA Astrophysics Data System (ADS)

    Perez-Gussinye, Marta; Andres-Martinez, Miguel; Morgan, Jason P.; Ranero, Cesar R.; Reston, Tim

    2016-04-01

    The West Iberia-Newfoundland (WIM-NF) conjugate margins have been geophysically and geologically surveyed for the last 30 years and have arguably become a paradigm for magma-poor extensional margins. Here we present a coherent picture of the WIM-NF rift to drift evolution that emerges from these observations and numerical modeling, and point out important differences that may exist with other magma-poor margins world-wide. The WIM-NF is characterized by a continental crust that thins asymmetrically and a wide and symmetric continent-ocean transition (COT) interpreted to consist of exhumed and serpentinised mantle with magmatic products increasing oceanward. The architectural evolution of these margins is mainly dominated by cooling under very slow extension velocities (<~6 mm/yr half-rate) and a lower crust that most probably was not extremely weak at the start of rifting. These conditions lead to a system where initially deformation is distributed over a broad area and the upper, lower crust and lithosphere are decoupled. As extension progresses upper, lower, crust and mantle become tightly coupled and deformation localizes due to strengthening and cooling during rifting. Coupling leads to asymmetric asthenospheric uplift and weakening of the hanginwall of the active fault, where a new fault forms. This continued process leads to the formation of an array of sequential faults that dip and become younger oceanward. Here we show that these processes acting in concert: 1) reproduce the margin asymmetry observed at the WIM-NF, 2) explain the fault geometry evolution from planar, to listric to detachment like by having one common Andersonian framework, 3) lead to the symmetric exhumation of mantle with little magmatism, and 4) explain the younging of the syn-rift towards the basin centre and imply that unconformities separating syn- and post-rift may be diachronous and younger towards the ocean. Finally, we show that different lower crustal rheologies lead to different

  9. Rift migration explains continental margin asymmetry and crustal hyper-extension.

    PubMed

    Brune, Sascha; Heine, Christian; Pérez-Gussinyé, Marta; Sobolev, Stephan V

    2014-01-01

    When continents break apart, continental crust and lithosphere are thinned until break-up is achieved and an oceanic basin is formed. The most remarkable and least understood structures associated with this process are up to 200 km wide areas of hyper-extended continental crust, which are partitioned between conjugate margins with pronounced asymmetry. Here we show, using high-resolution thermo-mechanical modelling, that hyper-extended crust and margin asymmetry are produced by steady state rift migration. We demonstrate that rift migration is accomplished by sequential, oceanward-younging, upper crustal faults, and is balanced through lower crustal flow. Constraining our model with a new South Atlantic plate reconstruction, we demonstrate that larger extension velocities may account for southward increasing width and asymmetry of these conjugate magma-poor margins. Our model challenges conventional ideas of rifted margin evolution, as it implies that during rift migration large amounts of material are transferred from one side of the rift zone to the other. PMID:24905463

  10. A regulatory perspective on choice of margin and statistical inference issue in non-inferiority trials.

    PubMed

    Hung, H M James; Wang, Sue-Jane; O'Neill, Robert

    2005-02-01

    Without a placebo arm, any non-inferiority inference involving assessment of the placebo effect under the active control trial setting is difficult. The statistical risk for falsely concluding non-inferiority cannot be evaluated unless the constancy assumption approximately holds that the effect of the active control under the historical trial setting where the control effect can be assessed carries to the noninferiority trial setting. The constancy assumption cannot be checked because of missing the placebo arm in the non-inferiority trial. Depending on how serious the violation of the assumption is thought to be, one may need to seek an alternative design strategy that includes a cushion for a very conservative non-inferiority analysis or shows superiority of the experimental treatment over the control. Determination of the non-inferiority margin depends on what objective the non-inferiority analysis is intended to achieve. The margin can be a fixed margin or a margin functionally defined. Between-trial differences always exist and need to be properly considered. PMID:16395994

  11. Rift migration explains continental margin asymmetry and crustal hyper-extension

    PubMed Central

    Brune, Sascha; Heine, Christian; Pérez-Gussinyé, Marta; Sobolev, Stephan V.

    2014-01-01

    When continents break apart, continental crust and lithosphere are thinned until break-up is achieved and an oceanic basin is formed. The most remarkable and least understood structures associated with this process are up to 200 km wide areas of hyper-extended continental crust, which are partitioned between conjugate margins with pronounced asymmetry. Here we show, using high-resolution thermo-mechanical modelling, that hyper-extended crust and margin asymmetry are produced by steady state rift migration. We demonstrate that rift migration is accomplished by sequential, oceanward-younging, upper crustal faults, and is balanced through lower crustal flow. Constraining our model with a new South Atlantic plate reconstruction, we demonstrate that larger extension velocities may account for southward increasing width and asymmetry of these conjugate magma-poor margins. Our model challenges conventional ideas of rifted margin evolution, as it implies that during rift migration large amounts of material are transferred from one side of the rift zone to the other. PMID:24905463

  12. The Homogeneity of School Achievement.

    ERIC Educational Resources Information Center

    Cahan, Sorel

    Since the measurement of school achievement involves the administration of achievement tests to various grades on various subjects, both grade level and subject matter contribute to within-school achievement variations. To determine whether achievement test scores vary most among different fields within a grade level, or within fields among…

  13. HEPEX - achievements and challenges!

    NASA Astrophysics Data System (ADS)

    Pappenberger, Florian; Ramos, Maria-Helena; Thielen, Jutta; Wood, Andy; Wang, Qj; Duan, Qingyun; Collischonn, Walter; Verkade, Jan; Voisin, Nathalie; Wetterhall, Fredrik; Vuillaume, Jean-Francois Emmanuel; Lucatero Villasenor, Diana; Cloke, Hannah L.; Schaake, John; van Andel, Schalk-Jan

    2014-05-01

    HEPEX is an international initiative bringing together hydrologists, meteorologists, researchers and end-users to develop advanced probabilistic hydrological forecast techniques for improved flood, drought and water management. HEPEX was launched in 2004 as an independent, cooperative international scientific activity. During the first meeting, the overarching goal was defined as: "to develop and test procedures to produce reliable hydrological ensemble forecasts, and to demonstrate their utility in decision making related to the water, environmental and emergency management sectors." The applications of hydrological ensemble predictions span across large spatio-temporal scales, ranging from short-term and localized predictions to global climate change and regional modeling. Within the HEPEX community, information is shared through its blog (www.hepex.org), meetings, testbeds and intercompaison experiments, as well as project reportings. Key questions of HEPEX are: * What adaptations are required for meteorological ensemble systems to be coupled with hydrological ensemble systems? * How should the existing hydrological ensemble prediction systems be modified to account for all sources of uncertainty within a forecast? * What is the best way for the user community to take advantage of ensemble forecasts and to make better decisions based on them? This year HEPEX celebrates its 10th year anniversary and this poster will present a review of the main operational and research achievements and challenges prepared by Hepex contributors on data assimilation, post-processing of hydrologic predictions, forecast verification, communication and use of probabilistic forecasts in decision-making. Additionally, we will present the most recent activities implemented by Hepex and illustrate how everyone can join the community and participate to the development of new approaches in hydrologic ensemble prediction.

  14. Fractal geometry of some Martian lava flow margins: Alba Patera

    NASA Technical Reports Server (NTRS)

    Kauhanen, K.

    1993-01-01

    Fractal dimension for a few lava flow margins on the gently sloping flanks of Alba Patera were measured using the structured walk method. Fractal behavior was observed at scales ranging from 20 to 100 pixels. The upper limit of the linear part of log(margin length) vs. log(scale) profile correlated well to the margin length. The lower limit depended on resolution and flow properties.

  15. Bounded Linear Stability Margin Analysis of Nonlinear Hybrid Adaptive Control

    NASA Technical Reports Server (NTRS)

    Nguyen, Nhan T.; Boskovic, Jovan D.

    2008-01-01

    This paper presents a bounded linear stability analysis for a hybrid adaptive control that blends both direct and indirect adaptive control. Stability and convergence of nonlinear adaptive control are analyzed using an approximate linear equivalent system. A stability margin analysis shows that a large adaptive gain can lead to a reduced phase margin. This method can enable metrics-driven adaptive control whereby the adaptive gain is adjusted to meet stability margin requirements.

  16. 17 CFR 41.46 - Type, form and use of margin.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 17 Commodity and Securities Exchanges 1 2011-04-01 2011-04-01 false Type, form and use of margin... FUTURES PRODUCTS Customer Accounts and Margin Requirements § 41.46 Type, form and use of margin. (a) When margin is required. Margin is required to be deposited whenever the required margin for security...

  17. Margins in Skin Excision Biopsies: Principles and Guidelines

    PubMed Central

    Ranjan, Richa; Singh, Lavleen; Arava, Sudheer K; Singh, Manoj Kumar

    2014-01-01

    Skin biopsies are usually undertaken to confirm a clinical diagnosis, to remove a lesion, and to determine the adequacy of excised tissue margin. A surgical margin is technically defined as the “edge” of the tissue removed. The term is especially pertinent when the tissue excised is suspected of being involved by a malignant process. One of the most important predictive and prognostic factors of a malignant lesion is whether the margins of the resected specimen are involved by the tumor or not. The purpose of this review is to provide an insight into grossing of a skin biopsy specimen with emphasis on techniques and reporting of excision biopsy margins. PMID:25484385

  18. Frequency-scanning marginal oscillator for ion cyclotron resonance spectroscopy

    NASA Astrophysics Data System (ADS)

    Kemper, Paul R.; Bowers, Michael T.

    1982-07-01

    A number of ion cyclotron resonance applications have arisen in the past few years which require a frequency-scanned detection system. Since the traditional marginal oscillator detector has always been a fixed-frequency detector, alternative detection techniques such as bridge circuit detectors have become widely used. In this paper we present an alternative to the bridge detector, namely, a frequency-scanning marginal oscillator. Requirements and modifications necessary to convert a marginal oscillator to frequency scanning operation are discussed in detail and the necessary circuit diagrams presented. Finally, a theoretical comparison is made between bridge circuit and marginal oscillator sensitivities.

  19. Plate tectonic evolution of circum-Antarctic passive margins

    SciTech Connect

    Scotese, C.R.; Lawver, L.A.; Sclater, J.G.; Mayes, C.L.; Norton, I.; Royer, J.

    1987-05-01

    Passive margins that formed during the Late Jurassic and Cretaceous account for approximately 80% of the 15,000-km circumference of Antarctica. There are no passive margins younger than Late Cretaceous. Approximately 28% of these margins are Late Jurassic in age, 24% are Early Cretaceous in age, and the remaining 48% formed during the Late Cretaceous. The tectonic style of the rifting events that formed these margins varies considerably along the perimeter of Antarctica. In several areas the initiation of sea-floor spreading was preceded by a long period of extension and predrift stretching (Wilkes Land). Along other portions of the margin, rifting proceeded rapidly with little evidence for a lengthy phase of pre-drift extension (Queen Maud Land). Though extension is the dominant tectonic style, there is evidence for large-scale strike-slip movement associated with the early phases of continental breakup along the coasts of Crown Princess Martha Land and Victoria Land. Except for a short segment of the margin between the West Antarctic peninsula and Marie Byrdland, the Antarctic passive margins have not been affected by subsequent subduction-related compressive deformation. This presentation will review the plate tectonic evolution of the Circum-Antarctic passive margins during five time intervals: Early Jurassic, Late Jurassic, Early Cretaceous, mid-Cretaceous, and latest Cretaceous. A map illustrating the relative amounts of extension along the margin of Antarctica will be presented, and a computer animation illustrating the breakup of Gondwana from an Antarctic perspective will be shown.

  20. Theoretical aspects of an electricity marginal cost model

    SciTech Connect

    Oyama, T.

    1986-01-01

    A separable programming model has been built to estimate electricity marginal costs. The model can be solved by applying linear programming techniques, hence marginal costs are obtained from shadow prices of model's optimal solution. In order to obtain more accurate and more detailed composition of electricity marginal costs, shadow prices are mathematically explained rigorously from model's structural points of view. Theoretical aspects of our electricity marginal cost model are investigated by applying theory of linear programming. Furthermore, various types of mathematical expression are also shown with their interpretation in the real power system.

  1. Theoretical aspects of an electricity marginal cost model

    SciTech Connect

    Oyama, T.

    1987-05-01

    A separable programming model has been built to estimate electricity marginal costs. The model can be solved by applying linear programming techniques, hence marginal costs are obtained from shadow prices of model's optimal solution. In order to obtain more accurate and more detailed composition of electricity marginal costs, shadow prices are mathematically explained rigorously from model's structural points of view. Theoretical aspects of our electricity marginal cost model are investigated by applying theory of linear programming. Furthermore, various types of mathematical expression are also shown with their interpretation in the real power system.

  2. Comparative biogeochemistry-ecosystem-human interactions on dynamic continental margins

    NASA Astrophysics Data System (ADS)

    Levin, Lisa A.; Liu, Kon-Kee; Emeis, Kay-Christian; Breitburg, Denise L.; Cloern, James; Deutsch, Curtis; Giani, Michele; Goffart, Anne; Hofmann, Eileen E.; Lachkar, Zouhair; Limburg, Karin; Liu, Su-Mei; Montes, Enrique; Naqvi, Wajih; Ragueneau, Olivier; Rabouille, Christophe; Sarkar, Santosh Kumar; Swaney, Dennis P.; Wassman, Paul; Wishner, Karen F.

    2015-01-01

    The oceans' continental margins face strong and rapid change, forced by a combination of direct human activity, anthropogenic CO2-induced climate change, and natural variability. Stimulated by discussions in Goa, India at the IMBER IMBIZO III, we (1) provide an overview of the drivers of biogeochemical variation and change on margins, (2) compare temporal trends in hydrographic and biogeochemical data across different margins, (3) review ecosystem responses to these changes, (4) highlight the importance of margin time series for detecting and attributing change and (5) examine societal responses to changing margin biogeochemistry and ecosystems. We synthesize information over a wide range of margin settings in order to identify the commonalities and distinctions among continental margin ecosystems. Key drivers of biogeochemical variation include long-term climate cycles, CO2-induced warming, acidification, and deoxygenation, as well as sea level rise, eutrophication, hydrologic and water cycle alteration, changing land use, fishing, and species invasion. Ecosystem responses are complex and impact major margin services. These include primary production, fisheries production, nutrient cycling, shoreline protection, chemical buffering, and biodiversity. Despite regional differences, the societal consequences of these changes are unarguably large and mandate coherent actions to reduce, mitigate and adapt to multiple stressors on continental margins.

  3. Comparative biogeochemistry-ecosystem-human interactions on dynamic continental margins

    USGS Publications Warehouse

    Levin, Lisa A.; Liu, Kon-Kee; Emeis, Kay-Christian; Breitburg, Denise L.; Cloern, James; Deutsch, Curtis; Giani, Michele; Goffart, Anne; Hofmann, Eileen E.; Lachkar, Zouhair; Limburg, Karin; Liu, Su-Mei; Montes, Enrique; Naqvi, Wajih; Ragueneau, Olivier; Rabouille, Christophe; Sarkar, Santosh Kumar; Swaney, Dennis P.; Wassman, Paul; Wishner, Karen F.

    2014-01-01

    The ocean’s continental margins face strong and rapid change, forced by a combination of direct human activity, anthropogenic CO2-induced climate change, and natural variability. Stimulated by discussions in Goa, India at the IMBER IMBIZO III, we (1) provide an overview of the drivers of biogeochemical variation and change on margins, (2) compare temporal trends in hydrographic and biogeochemical data across different margins (3) review ecosystem responses to these changes, (4) highlight the importance of margin time series for detecting and attributing change and (5) examine societal responses to changing margin biogeochemistry and ecosystems. We synthesize information over a wide range of margin settings in order to identify the commonalities and distinctions among continental margin ecosystems. Key drivers of biogeochemical variation include long-term climate cycles, CO2-induced warming, acidification, and deoxygenation, as well as sea level rise, eutrophication, hydrologic and water cycle alteration, changing land use, fishing, and species invasion. Ecosystem responses are complex and impact major margin services including primary production, fisheries production, nutrient cycling, shoreline protection, chemical buffering, and biodiversity. Despite regional differences, the societal consequences of these changes are unarguably large and mandate coherent actions to reduce, mitigate and adapt to multiple stressors on continental margins.

  4. Revealing quantum correlation by negativity of the Wigner function

    NASA Astrophysics Data System (ADS)

    Taghiabadi, Razieh; Akhtarshenas, Seyed Javad; Sarbishaei, Mohsen

    2016-05-01

    We analyze two two-mode continuous variable separable states with the same marginal states. We adopt the definition of classicality in the form of well-defined positive Wigner function describing the state and find that although the states possess positive local Wigner functions, they exhibit negative Wigner functions for the global states. Using the negativity of Wigner function as an indicator of nonclassicality, we show that despite these states possess different negativities of the Wigner function, they do not reveal this difference as phase space nonclassicalities such as negativity of the Mandel Q parameter or quadrature squeezing. We then concentrate on quantum correlation of these states and show that quantum discord and local quantum uncertainty, as two well-defined measures of quantum correlation, manifest the difference between negativity of the Wigner functions. The non-Gaussianity of these states is also examined and show that the difference in behavior of their non-Gaussianity is the same as the difference between negativity of their Wigner functions. We also investigate the influence of correlation rank criterion and find that when the states can be produced locally from classical states, the Wigner functions cannot reveal their quantum correlations.

  5. Linking margin morphology to sedimentary processes along the US East Coast passive continental margin

    NASA Astrophysics Data System (ADS)

    Brothers, D. S.; ten Brink, U. S.; Andrews, B.; Twichell, D.

    2010-12-01

    The morphology of the US East Coast continental slope and rise has a surprising amount of along-margin variation. Multibeam bathymetry datasets that cover the slope and rise from Cape Hatteras to Georges Bank provide a unique opportunity to analyze both first-order and higher-order morphologies, including submarine canyons, landslides, slumps and sedimentary bedforms. Using the morphological characterization coupled with seismic and core data, we hope to better understand how ancient and modern sedimentary processes control the shape of the margin. As a first step, the margin bathymetry was subdivided into 20 shelf-perpendicular regions from which several statistical parameters were analyzed. Within each region, the slope gradient was computed separately for down-slope and across-slope aspect directions. Distribution curves in each region for down- and across-slope gradients and seafloor roughness as functions of depth were grouped according to their statistical similarities. Four basic groups emerge and each approximately corresponds to known regions of Quaternary glacial, fluvial, current-controlled and gravity-driven sedimentary transport. In the second part of the study, published lithologic and chronostratigraphic frameworks of this margin were used to examine the relationship between seafloor morphology and the underlying geology. Along the upper continental rise, thick Quaternary deposits appear to have a strong influence on the short- and long-wavelength variation in rise topography, revealing a complex interplay between down-slope and along-slope sediment transport. Despite the close correlation between continental slope morphology and Quaternary environmental conditions, initial results suggest that the underlying, older, stratigraphy also plays a primary role. Along the continental slope, Quaternary processes appear to control the relief of slope-confined canyons and other short-wavelength (<5 km) topography, but the first order morphology of the slope

  6. Environment, agriculture, and settlement patterns in a marginal Polynesian landscape

    PubMed Central

    Kirch, P. V.; Hartshorn, A. S.; Chadwick, O. A.; Vitousek, P. M.; Sherrod, D. R.; Coil, J.; Holm, L.; Sharp, W. D.

    2004-01-01

    Beginning ca. A.D. 1400, Polynesian farmers established permanent settlements along the arid southern flank of Haleakala Volcano, Maui, Hawaiian Islands; peak population density (43-57 persons per km2) was achieved by A.D. 1700-1800, and it was followed by the devastating effects of European contact. This settlement, based on dryland agriculture with sweet potato as a main crop, is represented by >3,000 archaeological features investigated to date. Geological and environmental factors are the most important influence on Polynesian farming and settlement practices in an agriculturally marginal landscape. Interactions between lava flows, whose ages range from 3,000 to 226,000 years, and differences in rainfall create an environmental mosaic that constrained precontact Polynesian farming practices to a zone defined by aridity at low elevation and depleted soil nutrients at high elevation. Within this productive zone, however, large-scale agriculture was concentrated on older, tephra-blanketed lava flows; younger flows were reserved for residential sites, small ritual gardens, and agricultural temples. PMID:15210963

  7. APOBEC3 enzymes restrict marginal zone B cells

    PubMed Central

    Beck-Engeser, Gabriele B.; Winkelmann, Rebecca; Wheeler, Matthew L.; Shansab, Maryam; Yu, Philipp; Wünsche, Sarah; Walchhütter, Anja; Metzner, Mirjam; Vettermann, Christian; Eilat, Dan; DeFranco, Anthony; Jäck, Hans-Martin; Wabl, Matthias

    2016-01-01

    In general, a long-lasting immune response to viruses is achieved when they are infectious and replication-competent. In the mouse, the neutralizing antibody response to Friend murine leukemia virus is contributed by an allelic form of the enzyme Apobec3 (abbreviated A3). This is counterintuitive, because A3 directly controls viremia before the onset of adaptive anti-viral immune responses. It suggests that A3 also affects the antibody response directly. Here we studied the relative size of cell populations of the adaptive immune system as a function of A3 activity. We created a transgenic mouse that expresses all seven human A3 enzymes (hA3) and compared it to wild-type and mouse A3 (mA3)-deficient mice. A3 enzymes decreased the number of marginal zone (MZ) B cells, but not the number of follicular B or T cells. When mA3 was knocked out, the retroelement hitchhiker-1 and sialyl transferases encoded by genes close to it were overexpressed three and two orders of magnitude, respectively. We suggest that A3 shifts the balance, from the fast antibody response mediated by MZ B cells with little affinity maturation, to a more sustained germinal center B-cell response, which drives affinity maturation and, thereby, a better neutralizing response. PMID:25501566

  8. Environment, agriculture, and settlement patterns in a marginal Polynesian landscape

    USGS Publications Warehouse

    Kirch, P.V.; Hartshorn, A.S.; Chadwick, O.A.; Vitousek, P.M.; Sherrod, D.R.; Coil, J.; Holm, L.; Sharp, W.D.

    2004-01-01

    Beginning ca. A.D. 1400, Polynesian farmers established permanent settlements along the arid southern flank of Haleakala Volcano, Maui, Hawaiian Islands; peak population density (43-57 persons per km2) was achieved by A.D. 1700-1800, and it was followed by the devastating effects of European contact. This settlement, based on dryland agriculture with sweet potato as a main crop, is represented by >3,000 archaeological features investigated to date. Geological and environmental factors are the most important influence on Polynesian farming and settlement practices in an agriculturally marginal landscape. Interactions between lava flows, whose ages range from 3,000 to 226,000 years, and differences in rainfall create an environmental mosaic that constrained precontact Polynesian farming practices to a zone defined by aridity at low elevation and depleted soil nutrients at high elevation. Within this productive zone, however, large-scale agriculture was concentrated on older, tephra-blanketed lava flows; younger flows were reserved for residential sites, small ritual gardens, and agricultural temples.

  9. Morphology of turbidite systems within an active continental margin (the Palomares Margin, western Mediterranean)

    NASA Astrophysics Data System (ADS)

    Perez-Hernandez, S.; Comas, M. C.; Escutia, C.

    2014-08-01

    The Palomares Margin, an NNE-SSW segment of the South Iberian Margin located between the Alboran and the Algerian-Balearic basins, is dissected by two major submarine canyon systems: the Gata (in the South) and the Alías-Almanzora (in the North). New swath bathymetry, side-scan sonar images, accompanied by 5 kHz and TOPAS subbottom profiles, allow us to recognize these canyons as Mediterranean examples of medium-sized turbidite systems developed in a tectonically active margin. The Gata Turbidite System is confined between residual basement seamounts and exhibits incised braided channels that feed a discrete deep-sea fan, which points to a dominantly coarse-grained turbiditic system. The Alías-Almanzora Turbidite System, larger and less confined, is a good example of nested turbiditic system within the canyon. Concentric sediment waves characterize the Alías-Almanzora deep-sea fan, and the size and acoustic character of these bedforms suggest a fine-grained turbidite system. Both canyons are deeply entrenched on a narrow continental shelf and terminate at the base of the continental slope as channels that feed deep sea fans. While the Alías-Almanzora Turbidite System is the offshore continuation of seasonal rivers, the Gata Turbidite System is exclusively formed by headward erosion along the continental slope. In both cases, left-lateral transpressive deformation influences their location, longitudinal profiles, incision at the upper sections, and canyon bending associated with specific fault segments.

  10. Development-related PcG target in the apex 4 controls leaf margin architecture in Arabidopsis thaliana.

    PubMed

    Engelhorn, Julia; Reimer, Julia J; Leuz, Iris; Göbel, Ulrike; Huettel, Bruno; Farrona, Sara; Turck, Franziska

    2012-07-01

    In a reverse genetics screen based on a group of genes enriched for development-related Polycomb group targets in the apex (DPAs), we isolated DPA4 as a novel regulator of leaf margin shape. T-DNA insertion lines in the DPA4 locus display enhanced leaf margin serrations and enlarged petals, whereas overexpression of DPA4 results in smooth margins. DPA4 encodes a putative RAV (Related to ABI3/VP1) transcriptional repressor and is expressed in the lateral organ boundary region and in the sinus of leaf serrations. DPA4 expression domains overlap with those of the known leaf shape regulator CUP-SHAPED COTYLEDON 2 (CUC2) and we provide evidence that DPA4 negatively regulates CUC2 expression independently of MIR164A, an established regulator of CUC2. Taken together, the data suggest DPA4 as a newly identified player in the signalling network that controls leaf serrations in Arabidopsis thaliana. PMID:22675210

  11. Can Convective Instability of a Thickened Passive Margin Help Initiate Subduction?

    NASA Astrophysics Data System (ADS)

    Jull, M.; Kelemen, P. B.

    2001-12-01

    A fundamental part of plate tectonic theory is that plates are generated at spreading ridges and consumed at subduction zones. High density phase changes in the subducting slab help to pull the plate into the convecting mantle. McKenzie (1977) formulated expressions for the driving and resisting forces at a subduction zone and showed that at least 130 km of slab, moving at a rate of at least 1.3 cm/yr, would be required to subduct before the process would be self-sustaining. It was unclear from this work, or in more recent studies, how subduction is initiated in the first place. We propose that initiation of subduction at a passive margin may be aided by convective instability of a thickened igneous crustal section that was emplaced during initial rifting of the margin, such as is observed along much of the eastern boundary of the North Atlantic. We performed calculations of subsolidus phase equilibria of mafic and ultramafic lower crustal compositions that show that at the base of the crust at a thickened passive margin, high density phase transitions cause the density of the crust to exceed that of the underlying mantle at sub-Moho pressures by 50-100 kg3. Following recent work on convective instability of dense lower crust (Jull and Kelemen, JGR, 2001), we propose that colder temperatures at passive margins inhibit rapid convective removal of dense lower crust, and that initially only the deeper, ductile portions of the crust flow downwards via diffusion creep, allowing the density instability to continue. This results in subsidence and related sedimentation, which cause more and more of the lower crust to reach pressures where high density mineral phases form. Using a two-dimensional finite element model for the development of a convective instability, we evaluate this idea and determine the timescales and range of temperatures and pressures at which a thickened passive margin can produce a significant negative buoyancy force on the plate margin. A key

  12. Sci—Thur PM: Planning and Delivery — 04: Respiratory margin derivation and verification in partial breast irradiation

    SciTech Connect

    Quirk, S; Conroy, L; Smith, WL

    2014-08-15

    Partial breast irradiation (PBI) following breast-conserving surgery is emerging as an effective means to achieve local control and reduce irradiated breast volume. Patients are planned on a static CT image; however, treatment is delivered while the patient is free-breathing. Respiratory motion can degrade plan quality by reducing target coverage and/or dose homogeneity. A variety of methods can be used to determine the required margin for respiratory motion in PBI. We derive geometric and dosimetric respiratory 1D margin. We also verify the adequacy of the typical 5 mm respiratory margin in 3D by evaluating plan quality for increasing respiratory amplitudes (2–20 mm). Ten PBI plans were used for dosimetric evaluation. A database of volunteer respiratory data, with similar characteristics to breast cancer patients, was used for this study. We derived a geometric 95%-margin of 3 mm from the population respiratory data. We derived a dosimetric 95%-margin of 2 mm by convolving 1D dose profiles with respiratory probability density functions. The 5 mm respiratory margin is possibly too large when 1D coverage is assessed and could lead to unnecessary normal tissue irradiation. Assessing margins only for coverage may be insufficient; 3D dosimetric assessment revealed degradation in dose homogeneity is the limiting factor, not target coverage. Hotspots increased even for the smallest respiratory amplitudes, while target coverage only degraded at amplitudes greater than 10 mm. The 5 mm respiratory margin is adequate for coverage, but due to plan quality degradation, respiratory management is recommended for patients with respiratory amplitudes greater than 10 mm.

  13. Image-guided radiotherapy of the prostate using daily CBCT: the feasibility and likely benefit of implementing a margin reduction

    PubMed Central

    Benson, R J; Fairfoul, J; Cook, J; Huddart, R; Poynter, A

    2014-01-01

    Objective: To investigate whether planning target volume (PTV) margins may be safely reduced in radiotherapy of localized prostate cancer incorporating daily online tube potential-cone beam CT (CBCT) image guidance and the anticipated benefit in predicted rectal toxicity. Methods: The prostate-only clinical target volume (CTV2) and rectum were delineated on 1 pre-treatment CBCT each week in 18 randomly selected patients. By transposing these contours onto the original plan, dose–volume histograms (DVHs) for CTV2 and the rectum were each calculated and combined, for each patient, to produce a single mean DVH representative of the dose delivered over the treatment course. Plans were reoptimized using reduced CTV2 to PTV2 margins and the consequent radiobiological impact modelled by the tumour control probability (TCP) and normal tissue complication probability (NTCP) of the rectum. Results: All CBCT images were deemed of sufficient quality to identify the CTV and rectum. No loss of TCP was observed when plans using the standard 5-mm CTV2 to PTV2 margin of the centre were reoptimized with a 4- or 3-mm margin. Margin reduction was associated with a significant decrease in rectal NTCP (5–4 mm; p < 0.05 and 5–3 mm; p < 0.01). Conclusion: Using daily online image guidance with CBCT, a reduction in CTV2 to PTV2 margins to 3 mm is achievable without compromising tumour control. The consequent sparing of surrounding normal tissues is associated with reduced anticipated rectal toxicity. Advances in knowledge: Margin reduction is feasible and potentially beneficial. Centres with image-guided radiotherapy capability should consider assessing whether margin reduction is possible within their institutes. PMID:25354015

  14. New Exploration of Kerguelen Plateau Margins

    NASA Astrophysics Data System (ADS)

    Vially, R.; Roest, W. R.; Loubrieu, B.; Courreges, E.; Lecomte, J.; Patriat, M.; Pierre, D.; Schaming, M.; Schmitz, J.

    2008-12-01

    France ratified the United Nations Convention on the Law of the Sea in 1996, and has since undertaken an ambitious program of bathymetric and seismic data acquisition (EXTRAPLAC Program) to support claims for the extension of the legal continental shelf, in accordance with Article 76 of this convention. For this purpose, three oceanographic surveys took place on board of the R/V Marion Dufresne II on the Kerguelen Plateau, in Southern Indian Ocean: MD137-Kergueplac1 (February 2004), MD150-Kergueplac2 (October 2005) and MD165-Kergueplac3 (January 2008), operated by the French Polar Institute. Thus, more than 20 000 km of multibeam bathymetric, magnetic and gravimetric profiles, and almost 6 000 km of seismic profiles where acquired during a total of 62 days of survey in the study area. Ifremer's "rapid seismic" system was used, comprised of 4 guns and a 24 trace digital streamer, operated at speeds up to 10 knots. In addition to its use for the Extraplac Program, the data set issued from these surveys gives the opportunity to improve our knowledge of the structure of the Kerguelen Plateau and more particularly of its complex margins. In this poster, we will show the high resolution bathymetry (200 m) data set, that allows us to specify the irregular morphology of the sea floor in the north Kerguelen Plateau, characterised by ridges and volcanoes chains, radial to the plateau, that intersect the oceanic basin on the NE edge of the Kerguelen Plateau. We will also show magnetic and gravity data, which help us to understand the setting up of the oceanic plateau and the kinematics reconstructions. The seismic profiles show that the acoustic basement of the plateau is not much tectonised, and displays a very smooth texture, clearly contrasting it from typical oceanic basement. Both along the edge of the plateau as in the abyssal plain, sediments have variable thicknesses. The sediments on the margin of the plateau are up to 1200 meters thick and display irregular

  15. Toward laser cooling of negative lanthanum

    NASA Astrophysics Data System (ADS)

    Jordan, Elena; Cerchiari, Giovanni; Erlewein, Stefan; Kellerbauer, Alban; UNIC Team

    2016-05-01

    Anion laser cooling holds the potential to allow the production of ultracold ensembles of any negatively charged species by sympathetic cooling. It is a promising technique for cooling of antiprotons to a few mK and could clear the way for precision measurements on cold antihydrogen. Laser cooling of negative ions has never been achieved, since most species have no bound-bound electric dipole transitions. Negative lanthanum (La-) is one of the few anions with multiple electric dipole transitions. The bound-bound transition from the 3F2e ground state to the 3D1o excited state in La- has been proposed theoretically as a candidate for laser cooling. The potential laser cooling transition was identified using laser photodetachment spectroscopy and its excitation energy was measured. We have studied the aforementioned transition in a beam of La anions by high-resolution laser photodetachment spectroscopy. Seven of the nine expected hyperfine structure transitions have been resolved and the transition cross sections have been estimated from experimental observations. It was found that presently La- is the most promising candidate among the atomic anions. We plan to demonstrate the first direct laser cooling of negative ions in a linear radio frequency trap. We gratefully acknowledge support from the European Research Council (ERC).

  16. Sequential Monte Carlo tracking of the marginal artery by multiple cue fusion and random forest regression.

    PubMed

    Cherry, Kevin M; Peplinski, Brandon; Kim, Lauren; Wang, Shijun; Lu, Le; Zhang, Weidong; Liu, Jianfei; Wei, Zhuoshi; Summers, Ronald M

    2015-01-01

    Given the potential importance of marginal artery localization in automated registration in computed tomography colonography (CTC), we have devised a semi-automated method of marginal vessel detection employing sequential Monte Carlo tracking (also known as particle filtering tracking) by multiple cue fusion based on intensity, vesselness, organ detection, and minimum spanning tree information for poorly enhanced vessel segments. We then employed a random forest algorithm for intelligent cue fusion and decision making which achieved high sensitivity and robustness. After applying a vessel pruning procedure to the tracking results, we achieved statistically significantly improved precision compared to a baseline Hessian detection method (2.7% versus 75.2%, p<0.001). This method also showed statistically significantly improved recall rate compared to a 2-cue baseline method using fewer vessel cues (30.7% versus 67.7%, p<0.001). These results demonstrate that marginal artery localization on CTC is feasible by combining a discriminative classifier (i.e., random forest) with a sequential Monte Carlo tracking mechanism. In so doing, we present the effective application of an anatomical probability map to vessel pruning as well as a supplementary spatial coordinate system for colonic segmentation and registration when this task has been confounded by colon lumen collapse. PMID:25461335

  17. Geodynamic models of convergent margin tectonics: transition from rifted margin to overthrust belt and consequences for foreland-basin development

    SciTech Connect

    Stockmal, G.S.; Beaumont, C.; Boutilier, R.

    1986-02-01

    A quantitative geodynamic model for overthrusting of a passive continental margin during attempted continental subduction demonstrates the mechanical and thermal coupling between overthrust loads, the lithosphere, and the associated foreland basin. The model treated the lithosphere as a two-dimensional nonuniform elastic plate whose strength is controlled thermally. The thermal and flexural evolution of a margin is followed from initial rifting and passive-margin development, through overthrusting and foreland-basin deposition, to postdeformational erosion.

  18. Negative hydrogen ion production mechanisms

    SciTech Connect

    Bacal, M.; Wada, M.

    2015-06-15

    Negative hydrogen/deuterium ions can be formed by processes occurring in the plasma volume and on surfaces facing the plasma. The principal mechanisms leading to the formation of these negative ions are dissociative electron attachment to ro-vibrationally excited hydrogen/deuterium molecules when the reaction takes place in the plasma volume, and the direct electron transfer from the low work function metal surface to the hydrogen/deuterium atoms when formation occurs on the surface. The existing theoretical models and reported experimental results on these two mechanisms are summarized. Performance of the negative hydrogen/deuterium ion sources that emerged from studies of these mechanisms is reviewed. Contemporary negative ion sources do not have negative ion production electrodes of original surface type sources but are operated with caesium with their structures nearly identical to volume production type sources. Reasons for enhanced negative ion current due to caesium addition to these sources are discussed.

  19. Mechanical metamaterials with negative compressibility transitions

    NASA Astrophysics Data System (ADS)

    Nicolaou, Zachary G.; Motter, Adilson E.

    2012-07-01

    When tensioned, ordinary materials expand along the direction of the applied force. Here, we explore network concepts to design metamaterials exhibiting negative compressibility transitions, during which a material undergoes contraction when tensioned (or expansion when pressured). Continuous contraction of a material in the same direction of an applied tension, and in response to this tension, is inherently unstable. The conceptually similar effect we demonstrate can be achieved, however, through destabilizations of (meta)stable equilibria of the constituents. These destabilizations give rise to a stress-induced solid-solid phase transition associated with a twisted hysteresis curve for the stress-strain relationship. The strain-driven counterpart of negative compressibility transitions is a force amplification phenomenon, where an increase in deformation induces a discontinuous increase in response force. We suggest that the proposed materials could be useful for the design of actuators, force amplifiers, micromechanical controls, and protective devices.

  20. Mechanical metamaterials with negative compressibility transitions.

    PubMed

    Nicolaou, Zachary G; Motter, Adilson E

    2012-07-01

    When tensioned, ordinary materials expand along the direction of the applied force. Here, we explore network concepts to design metamaterials exhibiting negative compressibility transitions, during which a material undergoes contraction when tensioned (or expansion when pressured). Continuous contraction of a material in the same direction of an applied tension, and in response to this tension, is inherently unstable. The conceptually similar effect we demonstrate can be achieved, however, through destabilizations of (meta)stable equilibria of the constituents. These destabilizations give rise to a stress-induced solid-solid phase transition associated with a twisted hysteresis curve for the stress-strain relationship. The strain-driven counterpart of negative compressibility transitions is a force amplification phenomenon, where an increase in deformation induces a discontinuous increase in response force. We suggest that the proposed materials could be useful for the design of actuators, force amplifiers, micromechanical controls, and protective devices. PMID:22609557

  1. Mean-reversion in income over feed cost margins: evidence and implications for managing margin risk by US dairy producers.

    PubMed

    Bozic, M; Newton, J; Thraen, C S; Gould, B W

    2012-12-01

    With the increased volatility of feed prices, dairy farm managers are no longer concerned with managing only milk price volatility, but are considering the adoption of risk management programs that address income over feed cost (IOFC) margin risk. Successful margin risk management should be founded on an understanding of the behavior of IOFC margins. To that end, we have constructed forward IOFC margins using Class III milk, corn, and soybean meal futures prices. We focus on the characteristics of the term structure of forward IOFC margins, that is, the sequence of forward margins for consecutive calendar months, all observed on the same trading day. What is apparent from the shapes of these term structures is that both in times when margins were exceptionally high and in times when they were disastrously low, market participants expected that a reversal back to average margin levels would not come quickly, but rather would take up to 9 mo. Slopes of the forward margin term structure before and after most of the major swings in IOFC indicate these shocks were mostly unanticipated, whereas the time needed for recovery to normal margin levels was successfully predicted. This suggests that IOFC margins may exhibit slow mean-reverting, rather than predictable cyclical behavior, as is often suggested in the popular press. This finding can be exploited to design a successful catastrophic risk management program by initiating protection at 9 to 12 mo before futures contract maturity. As a case study, we analyzed risk management strategies for managing IOFC margins that used Livestock Gross Margin for Dairy Cattle insurance contracts and created 2 farm profiles. The first one represents dairy farms that grow most of their feed, whereas the second profile is designed to capture the risk exposure of dairy farms that purchase all their dairy herd, dry cow, and heifer feed. Our case study of this program encompasses the 2009 period, which was characterized by exceptionally

  2. Margin index: a useful tool for the breast surgeon?

    PubMed Central

    Edwards, Claire; Gao, Feng; Freedman, Gary M.; Margenthaler, Julie A.; Fisher, Carla

    2016-01-01

    Background In breast conservation surgery (BCS) for breast cancer, the appropriate surgical margin is controversial. Margin index, a mathematical relationship between tumor size and closest margin, has been shown to be predictive of the probability of residual cancer following BCS for early stage breast cancer. We applied this tool to the same population of patients at our institution to evaluate its ability to predict residual disease after BCS. Methods We retrospectively reviewed a prospectively maintained database of women undergoing BCS between 1980-2010 at the University of Pennsylvania. 246 women underwent re-excision due to close margins. Average margin index between groups with and without residual disease in the re-excision specimen was compared using Student's t-test. A receiver operating curve (ROC) was created using logistic regression to assess the overall diagnostic ability of the margin index on the presence or absence of residual disease. Results Of patients who underwent re-excision, 29% of patients had residual disease. We analyzed several cutoff values for margin index, but none proved to be significant predictors of residual disease. Average margin index was significantly higher for patients without residual disease compared to patients with residual invasive cancer but not for patients with residual DCIS. Conclusions In women undergoing BCS for early-stage breast cancer at our institution, margin index was not predictive of the presence of residual cancer on re-excision. We hypothesize that the predictive ability of margin index is likely limited by several factors including presence of DCIS and the location and extent of the close margin. PMID:24746949

  3. Geology of New England passive margin

    SciTech Connect

    Austin, J.A. Jr.; Uchupi, E.; Shaughnessy, D.R. III; Ballard, R.D.

    1980-01-01

    The New England continental margin began to develop in the Middle Triassic, when rifting of Precambrian/Paleozoic terrane produced a complex arrangement of horsts and grabens. During the Late Triassic-Early Jurassic, these grabens were filled with terrigenous clastics, volcanics, and evaporites. When plate separation took place and seafloor spreading began approximately 195 to 190 m.y.B.P., the newly formed continental edge was uplifted and eroded, truncating preexisting rift structures. As North America began to drift away from Africa, subsidence occurred along a series of normal faults now beneath the outer continental shelf. This hinge zone may represent the boundary between continental crust and a transitional zone of continental and oceanic crustal fragments. Atop the faulted and subsiding crustal platform, thick sediments were deposited. The lower part of the drift sequence is an evaporite-carbonate unit of Early-Middle Jurassic age, and the upper part is a clastic wedge of Middle Jurassic to Cenozoic age. More than 80% of these sediments are Jurassic. Their total thickness may be as much as 13 km beneath the southeastern part of Georges Bank.

  4. Understanding continental margin biodiversity: a new imperative.

    PubMed

    Levin, Lisa A; Sibuet, Myriam

    2012-01-01

    Until recently, the deep continental margins (200-4,000 m) were perceived as monotonous mud slopes of limited ecological or environmental concern. Progress in seafloor mapping and direct observation now reveals unexpected heterogeneity, with a mosaic of habitats and ecosystems linked to geomorphological, geochemical, and hydrographic features that influence biotic diversity. Interactions among water masses, terrestrial inputs, sediment diagenesis, and tectonic activity create a multitude of ecological settings supporting distinct communities that populate canyons and seamounts, high-stress oxygen minimum zones, and methane seeps, as well as vast reefs of cold corals and sponges. This high regional biodiversity is fundamental to the production of valuable fisheries, energy, and mineral resources, and performs critical ecological services (nutrient cycling, carbon sequestration, nursery and habitat support). It is under significant threat from climate change and human resource extraction activities. Serious actions are required to preserve the functions and services provided by the deep-sea settings we are just now getting to know. PMID:22457970

  5. Marginal marine evaporites, lower Cretaceous of Arkansas

    SciTech Connect

    Lock, B.E.; Darling, B.K.; Rex, I.D.

    1983-09-01

    The mixed evaporite/carbonate/terrigenous clastic sediments of the DeQueen formation, in southwestern Arkansas, were deposited at the landward margin of a broad shallow lagoon formed behind the Glen Rose reef. The lower part of the formation contains discontinuous beds of gypsum, ranging in thickness from a few centimeters to composite beds > 3 m (10 ft), and displaying mosaic structure with vertically oriented, elongate nodules. The upper part of the formation contains no gypsum beds, but halite pseudomorphs at the base of and within some of the thin limestones suggest the presence of supratidal brine pools. Several minor unconformities exist, of which one has a regional extent and is underlain by red-brown mudstones. Algal-mat lamination, lenticular gypsum pseudomorphs (an intrastratal growth form), and syneresis cracks occur in the limestones, and a supratidal environment is envisaged for a significant proportion of the time of deposition. The limestones generally have a restricted fauna of ostracods, bivalves, cerithid gastropods, serpulid worm, and miliolid Foraminifera, and range in texture from lime mudstones to grainstones. Some of the thinner bedded units are rippled, and some ripples were truncated during periods of emergence. The limestones are believed to represent periods of shallow water, slightly hypersaline to slightly hyposaline conditions of variable energy. The regressive trend displayed by these two divisions continued with deposition of the overlying formation. The uppermost 3 m (10 ft) of the DeQueen consists of mudstone with a thin marl at the top.

  6. Ice sheet margins and ice shelves

    NASA Technical Reports Server (NTRS)

    Thomas, R. H.

    1984-01-01

    The effect of climate warming on the size of ice sheet margins in polar regions is considered. Particular attention is given to the possibility of a rapid response to warming on the order of tens to hundreds of years. It is found that the early response of the polar regions to climate warming would be an increase in the area of summer melt on the ice sheets and ice shelves. For sufficiently large warming (5-10C) the delayed effects would include the breakup of the ice shelves by an increase in ice drainage rates, particularly from the ice sheets. On the basis of published data for periodic changes in the thickness and melting rates of the marine ice sheets and fjord glaciers in Greenland and Antarctica, it is shown that the rate of retreat (or advance) of an ice sheet is primarily determined by: bedrock topography; the basal conditions of the grounded ice sheet; and the ice shelf condition downstream of the grounding line. A program of satellite and ground measurements to monitor the state of ice sheet equilibrium is recommended.

  7. Selective Harvesting of Marginating-pulmonary Leukocytes.

    PubMed

    Shaashua, Lee; Sorski, Liat; Melamed, Rivka; Ben-Eliyahu, Shamgar

    2016-01-01

    Marginating-pulmonary (MP) leukocytes are leukocytes that adhere to the inner endothelium of the lung capillaries. MP-leukocytes were shown to exhibit unique composition and characteristics compared to leukocytes of other immune compartments. Evidence suggests higher cytotoxicity of natural killer cells, and a distinct pro- and anti-inflammatory profile of the MP-leukocyte population compared to circulating or splenic immunocytes. The method presented herein enables selective harvesting of MP-leukocytes by forced perfusion of the lungs in either mice or rats. In contrast to other methods used to extract lung-leukocytes, such as tissue grinding and biological degradation, this method exclusively yields leukocytes from the lung capillaries, uncontaminated with parenchymal, interstitial, and broncho-alveolar cells. In addition, the perfusion technique better preserves the integrity and the physiological milieu of MP-leukocytes, without inducing physiological responses due to tissue processing. This unique MP leukocyte population is strategically located to identify and react towards abnormal circulating cells, as all circulating malignant cells and infected cells are detained while passing through the lung capillaries, physically interacting with endothelial cells and resident leukocytes,. Thus, selective harvesting of MP-leukocytes and their study under various conditions may advance our understanding of their biological and clinical significance, specifically with respect to controlling circulating aberrant cells and lung-related diseases. PMID:27023665

  8. Statistical analysis of marginal count failure data.

    PubMed

    Karim, M R; Yamamoto, W; Suzuki, K

    2001-06-01

    Manufacturers want to assess the quality and reliability of their products. Specifically, they want to know the exact number of failures from the sales transacted during a particular month. Information available today is sometimes incomplete as many companies analyze their failure data simply comparing sales for a total month from a particular department with the total number of claims registered for that given month. This information--called marginal count data--is, thus, incomplete as it does not give the exact number of failures of the specific products that were sold in a particular month. In this paper we discuss nonparametric estimation of the mean numbers of failures for repairable products and the failure probabilities for nonrepairable products. We present a nonhomogeneous Poisson process model for repairable products and a multinomial model and its Poisson approximation for nonrepairable products. A numerical example is given and a simulation is carried out to evaluate the proposed methods of estimating failure probabilities under a number of possible situations. PMID:11458656

  9. Complex gas hydrate from the Cascadia margin.

    PubMed

    Lu, Hailong; Seo, Yu-taek; Lee, Jong-won; Moudrakovski, Igor; Ripmeester, John A; Chapman, N Ross; Coffin, Richard B; Gardner, Graeme; Pohlman, John

    2007-01-18

    Natural gas hydrates are a potential source of energy and may play a role in climate change and geological hazards. Most natural gas hydrate appears to be in the form of 'structure I', with methane as the trapped guest molecule, although 'structure II' hydrate has also been identified, with guest molecules such as isobutane and propane, as well as lighter hydrocarbons. A third hydrate structure, 'structure H', which is capable of trapping larger guest molecules, has been produced in the laboratory, but it has not been confirmed that it occurs in the natural environment. Here we characterize the structure, gas content and composition, and distribution of guest molecules in a complex natural hydrate sample recovered from Barkley canyon, on the northern Cascadia margin. We show that the sample contains structure H hydrate, and thus provides direct evidence for the natural occurrence of this hydrate structure. The structure H hydrate is intimately associated with structure II hydrate, and the two structures contain more than 13 different hydrocarbon guest molecules. We also demonstrate that the stability field of the complex gas hydrate lies between those of structure II and structure H hydrates, indicating that this form of hydrate is more stable than structure I and may thus potentially be found in a wider pressure-temperature regime than can methane hydrate deposits. PMID:17230188

  10. Seismic margins and calibration of piping systems

    SciTech Connect

    Shieh, L.C.; Tsai, N.C.; Yang, M.S.; Wong, W.L.

    1985-01-01

    The Seismic Safety Margins Research Program (SSMRP) is a US Nuclear Regulatory Commission-funded, multiyear program conducted by Lawrence Livermore National Laboratory (LLNL). Its objective is to develop a complete, fully coupled analysis procedure for estimating the risk of earthquake-induced radioactive release from a commercial nuclear power plant and to determine major contributors to the state-of-the-art seismic and systems analysis process and explicitly includes the uncertainties in such a process. The results will be used to improve seismic licensing requirements for nuclear power plants. In Phase I of SSMRP, the overall seismic risk assessment methodology was developed and assembled. The application of this methodology to the seismic PRA (Probabilistic Risk Assessment) at the Zion Nuclear Power Plant has been documented. This report documents the method deriving response factors. The response factors, which relate design calculated responses to best estimate values, were used in the seismic response determination of piping systems for a simplified seismic probablistic risk assessment. 13 references, 31 figures, 25 tables.

  11. Multicategory Large-Margin Unified Machines

    PubMed Central

    Zhang, Chong; Liu, Yufeng

    2013-01-01

    Hard and soft classifiers are two important groups of techniques for classification problems. Logistic regression and Support Vector Machines are typical examples of soft and hard classifiers respectively. The essential difference between these two groups is whether one needs to estimate the class conditional probability for the classification task or not. In particular, soft classifiers predict the label based on the obtained class conditional probabilities, while hard classifiers bypass the estimation of probabilities and focus on the decision boundary. In practice, for the goal of accurate classification, it is unclear which one to use in a given situation. To tackle this problem, the Large-margin Unified Machine (LUM) was recently proposed as a unified family to embrace both groups. The LUM family enables one to study the behavior change from soft to hard binary classifiers. For multicategory cases, however, the concept of soft and hard classification becomes less clear. In that case, class probability estimation becomes more involved as it requires estimation of a probability vector. In this paper, we propose a new Multicategory LUM (MLUM) framework to investigate the behavior of soft versus hard classification under multicategory settings. Our theoretical and numerical results help to shed some light on the nature of multicategory classification and its transition behavior from soft to hard classifiers. The numerical results suggest that the proposed tuned MLUM yields very competitive performance. PMID:24415909

  12. The Impact of Reading Achievement on Overall Academic Achievement

    ERIC Educational Resources Information Center

    Churchwell, Dawn Earheart

    2009-01-01

    This study examined the relationship between reading achievement and achievement in other subject areas. The purpose of this study was to determine if there was a correlation between reading scores as measured by the Standardized Test for the Assessment of Reading (STAR) and academic achievement in language arts, math, science, and social studies…

  13. Attitude Towards Physics and Additional Mathematics Achievement Towards Physics Achievement

    ERIC Educational Resources Information Center

    Veloo, Arsaythamby; Nor, Rahimah; Khalid, Rozalina

    2015-01-01

    The purpose of this research is to identify the difference in students' attitude towards Physics and Additional Mathematics achievement based on gender and relationship between attitudinal variables towards Physics and Additional Mathematics achievement with achievement in Physics. This research focused on six variables, which is attitude towards…

  14. Predicting Mathematics Achievement: The Influence of Prior Achievement and Attitudes

    ERIC Educational Resources Information Center

    Hemmings, Brian; Grootenboer, Peter; Kay, Russell

    2011-01-01

    Achievement in mathematics is inextricably linked to future career opportunities, and therefore, understanding those factors that influence achievement is important. This study sought to examine the relationships among attitude towards mathematics, ability and mathematical achievement. This examination was also supported by a focus on gender…

  15. 24. Duplicate negative of an historic negative. 'AERIAL VIEW OF ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    24. Duplicate negative of an historic negative. 'AERIAL VIEW OF AREA 'B' HOLSTON ORDNANCE WORKS.' 1944. #OCMH 4-12.2ASAV3 in Super Explosives Program RDX and Its Composition A, B, & C, Record Group No. 319, National Archives, Washington, D.C. - Holston Army Ammunition Plant, RDX-and-Composition-B Manufacturing Line 9, Kingsport, Sullivan County, TN

  16. Negative cooperativity in regulatory enzymes.

    PubMed

    Levitzki, A; Koshland, D E

    1969-04-01

    Negative cooperativity has been observed in CTP synthetase, an allosteric enzyme which contains a regulatory site. Thus, the same enzyme exhibits negative cooperativity for GTP (an effector) and glutamine (a substrate) and positive cooperativity for ATP and UTP (both substrates). In the process of the delineation of these phenomena, diagnostic procedures for negative cooperativity were developed. Application of these procedures to other enzymes indicates that negative cooperativity is a characteristic of many of them. These findings add strong support for the sequential model of subunit interactions which postulates that ligand-induced conformational changes are responsible for regulatory and cooperative phenomena in enzymes. PMID:5256410

  17. Negative ions of polyatomic molecules.

    PubMed Central

    Christophorou, L G

    1980-01-01

    In this paper general concepts relating to, and recent advances in, the study of negative ions of polyatomic molecules area discussed with emphasis on halocarbons. The topics dealt with in the paper are as follows: basic electron attachment processes, modes of electron capture by molecules, short-lived transient negative ions, dissociative electron attachment to ground-state molecules and to "hot" molecules (effects of temperature on electron attachment), parent negative ions, effect of density, nature, and state of the medium on electron attachment, electron attachment to electronically excited molecules, the binding of attached electrons to molecules ("electron affinity"), and the basic and the applied significance of negative-ion studies. PMID:7428744

  18. Intrinsic Negative Mass from Nonlinearity

    NASA Astrophysics Data System (ADS)

    Di Mei, F.; Caramazza, P.; Pierangeli, D.; Di Domenico, G.; Ilan, H.; Agranat, A. J.; Di Porto, P.; DelRe, E.

    2016-04-01

    We propose and provide experimental evidence of a mechanism able to support negative intrinsic effective mass. The idea is to use a shape-sensitive nonlinearity to change the sign of the mass in the leading linear propagation equation. Intrinsic negative-mass dynamics is reported for light beams in a ferroelectric crystal substrate, where the diffusive photorefractive nonlinearity leads to a negative-mass Schrödinger equation. The signature of inverted dynamics is the observation of beams repelled from strongly guiding integrated waveguides irrespective of wavelength and intensity and suggests shape-sensitive nonlinearity as a basic mechanism leading to intrinsic negative mass.

  19. Neurobiological background of negative symptoms.

    PubMed

    Galderisi, Silvana; Merlotti, Eleonora; Mucci, Armida

    2015-10-01

    Studies investigating neurobiological bases of negative symptoms of schizophrenia failed to provide consistent findings, possibly due to the heterogeneity of this psychopathological construct. We tried to review the findings published to date investigating neurobiological abnormalities after reducing the heterogeneity of the negative symptoms construct. The literature in electronic databases as well as citations and major articles are reviewed with respect to the phenomenology, pathology, genetics and neurobiology of schizophrenia. We searched PubMed with the keywords "negative symptoms," "deficit schizophrenia," "persistent negative symptoms," "neurotransmissions," "neuroimaging" and "genetic." Additional articles were identified by manually checking the reference lists of the relevant publications. Publications in English were considered, and unpublished studies, conference abstracts and poster presentations were not included. Structural and functional imaging studies addressed the issue of neurobiological background of negative symptoms from several perspectives (considering them as a unitary construct, focusing on primary and/or persistent negative symptoms and, more recently, clustering them into factors), but produced discrepant findings. The examined studies provided evidence suggesting that even primary and persistent negative symptoms include different psychopathological constructs, probably reflecting the dysfunction of different neurobiological substrates. Furthermore, they suggest that complex alterations in multiple neurotransmitter systems and genetic variants might influence the expression of negative symptoms in schizophrenia. On the whole, the reviewed findings, representing the distillation of a large body of disparate data, suggest that further deconstruction of negative symptomatology into more elementary components is needed to gain insight into underlying neurobiological mechanisms. PMID:25797499

  20. Towards intraoperative assessment of tumor margins in breast surgery using optical coherence elastography (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Kennedy, Brendan F.; Wijesinghe, Philip; Allen, Wes M.; Chin, Lixin; Latham, Bruce; Saunders, Christobel M.; Sampson, David D.

    2016-03-01

    Surgical excision of tumor is a critical factor in the management of breast cancer. The most common surgical procedure is breast-conserving surgery. The surgeon's goal is to remove the tumor and a rim of healthy tissue surrounding the tumor: the surgical margin. A major issue in breast-conserving surgery is the absence of a reliable tool to guide the surgeon in intraoperatively assessing the margin. A number of techniques have been proposed; however, the re-excision rate remains high and has been reported to be in the range 30-60%. New tools are needed to address this issue. Optical coherence elastography (OCE) shows promise as a tool for intraoperative tumor margin assessment in breast-conserving surgery. Further advances towards clinical translation are limited by long scan times and small fields of view. In particular, scanning over sufficient areas to assess the entire margin in an intraoperative timeframe has not been shown to be feasible. Here, we present a protocol allowing ~75% of the surgical margins to be assessed within 30 minutes. To achieve this, we have incorporated a 65 mm-diameter (internal), wide-aperture annular piezoelectric transducer, allowing the entire surface of the excised tumor mass to be automatically imaged in an OCT mosaic comprised of 10 × 10 mm tiles. As OCT is effective in identifying adipose tissue, our protocol uses the wide-field OCT to selectively guide subsequent local OCE scanning to regions of solid tissue which often present low contrast in OCT images. We present promising examples from freshly excised human breast tissue.

  1. Economic Recovery of Oil Trapped at Fan Margins Using High Angle Wells and Multiple Hydraulic Fractures

    SciTech Connect

    Mike L. Laue

    1997-05-30

    The distal fan margin in the northeast portion of the Yowlumne field contains significant reserves but is not economical to develop using vertical wells. Numerous interbedded shales and deteriorating rock properties limit producibility. In addition, extreme depths (13,000 ft) present a challenging environment for hydraulic fracturing and artificial lift. Lastly, a mature waterflood increases risk because of the uncertainty with size and location of flood fronts. This project attempts to demonstrate the effectiveness of exploiting the distal fan margin of this slope-basin clastic reservoir through the use of a high-angle well completed with multiple hydraulic-fracture treatments. The combination of a high-angle (or horizontal) well and hydraulic fracturing will allow greater pay exposure than can be achieved with conventional vertical wells while maintaining vertical communication between thin interbedded layers and the wellbore. The equivalent production rate and reserves of three vertical wells are anticipated at one-half to two-thirds the cost.

  2. Power systems locational marginal pricing in deregulated markets

    NASA Astrophysics Data System (ADS)

    Wang, Hui-Fung Francis

    Since the beginning of the 1990s, the electricity business is transforming from a vertical integrating business to a competitive market operations. The generation, transmission, distribution subsystem of an electricity utility are operated independently as Genco (generation subsystem), Transco (transmission subsystem), and Distco (distribution subsystem). This trend promotes more economical inter- and intra regional transactions to be made by the participating companies and the users of electricity to achieve the intended objectives of deregulation. There are various types of electricity markets that are implemented in the North America in the past few years. However, transmission congestion management becomes a key issue in the electricity market design as more bilateral transactions are traded across long distances competing for scarce transmission resources. It directly alters the traditional concept of energy pricing and impacts the bottom line, revenue and cost of electricity, of both suppliers and buyers. In this research, transmission congestion problem in a deregulated market environment is elucidated by implementing by the Locational Marginal Pricing (LMP) method. With a comprehensive understanding of the LMP method, new mathematical tools will aid electric utilities in exploring new business opportunities are developed and presented in this dissertation. The dissertation focuses on the development of concept of (LMP) forecasting and its implication to the market participants in deregulated market. Specifically, we explore methods of developing fast LMP calculation techniques that are differ from existing LMPs. We also explore and document the usefulness of the proposed LMP in determining electricity pricing of a large scale power system. The developed mathematical tools use of well-known optimization techniques such as linear programming that are support by several flow charts. The fast and practical security constrained unit commitment methods are the

  3. Lower body negative pressure, experiment M092

    NASA Technical Reports Server (NTRS)

    Johnson, R. L.; Nicogossian, A. E.; Jackson, M. M.; Hoffler, G. W.; Wolthuis, R. A.

    1973-01-01

    Evaluation of orthostatic intolerance has been achieved by the use of lower body negative pressure (LBNP). The LBNP technique, though independent of gravity, simulates its effect by exposing the legs and the lower abdomen to reduced ambient pressures. This LBNP experiment, conducted during the 56-day simulation of the Skylab environment, was designed to supply baseline information on cardiovascular responses to periodic orthostatic stress. Impaired orthostatic tolerance, manifested by the increased heart rate, diminished systolic and pulse pressure, and increased tendency to syncope in the upright position, or during LBNP, was not observed in this experiment.

  4. Continental margin sedimentation: from sediment transport to sequence stratigraphy

    USGS Publications Warehouse

    Nittrouer, Charles A., (Edited By); Austin, James A.; Field, Michael E.; Kravitz, Joseph H.; Syvitski, James P.M.; Wiberg, Patricia L.

    2007-01-01

    This volume on continental margin sedimentation brings together an expert editorial and contributor team to create a state-of-the-art resource. Taking a global perspective, the book spans a range of timescales and content, ranging from how oceans transport particles, to how thick rock sequences are formed on continental margins. - Summarizes and integrates our understanding of sedimentary processes and strata associated with fluvial dispersal systems on continental shelves and slopes - Explores timescales ranging from particle transport at one extreme, to deep burial at the other - Insights are presented for margins in general, and with focus on a tectonically active margin (northern California) and a passive margin (New Jersey), enabling detailed examination of the intricate relationships between a wide suite of sedimentary processes and their preserved stratigraphy - Includes observational studies which document the processes and strata found on particular margins, in addition to numerical models and laboratory experimentation, which provide a quantitative basis for extrapolation in time and space of insights about continental-margin sedimentation - Provides a research resource for scientists studying modern and ancient margins, and an educational text for advanced students in sedimentology and stratigraphy

  5. 46 CFR 171.015 - Location of margin line.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 46 Shipping 7 2013-10-01 2013-10-01 false Location of margin line. 171.015 Section 171.015 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) SUBDIVISION AND STABILITY SPECIAL RULES PERTAINING TO VESSELS CARRYING PASSENGERS General § 171.015 Location of margin line. (a) A vessel with...

  6. Power margin improvement for OFDMA-PON using hierarchical modulation.

    PubMed

    Cao, Pan; Hu, Xiaofeng; Zhuang, Zhiming; Zhang, Liang; Chang, Qingjiang; Yang, Qi; Hu, Rong; Su, Yikai

    2013-04-01

    We propose and experimentally demonstrate a hierarchical modulation scheme to improve power margin for orthogonal frequency division multiple access-passive optical networks (OFDMA-PONs). In a PON system, under the same launched optical power, optical network units (ONUs) have different power margins due to unequal distribution fiber lengths. The power margin of the PON system is determined by the ONU with the lowest power margin. In our proposed scheme, ONUs with long and short distribution fibers are grouped together, and downstream signals for the paired ONUs are mapped onto the same OFDM subcarriers using hierarchical modulation. In a pair of ONUs, part of the power margin of the ONU with short distribution fiber is re-allocated to the ONU with long distribution fiber. Therefore, the power margin of the ONU with the longest distribution fiber can be increased, leading to the power margin improvement of the PON system. Experimental results show that the hierarchical modulation scheme improves the power margin by 2.7 dB for an OFDMA-PON system, which can be used to support more users or extend transmission distance. PMID:23571916

  7. A risk-informed approach to safety margins analysis

    SciTech Connect

    Curtis Smith; Diego Mandelli

    2013-07-01

    The Risk Informed Safety Margins Characterization (RISMC) Pathway is a systematic approach developed to characterize and quantify safety margins of nuclear power plant structures, systems and components. The model has been tested on the Advanced Test Reactor (ATR) at Idaho National Lab.

  8. Particle margination and its implications on intravenous anticancer drug delivery.

    PubMed

    Carboni, Erik; Tschudi, Katherine; Nam, Jaewook; Lu, Xiuling; Ma, Anson W K

    2014-06-01

    "Margination" refers to the movement of particles in flow toward the walls of a channel. The term was first coined in physiology for describing the behavior of white blood cells (WBCs) and platelets in blood flow. The margination of particles is desirable for anticancer drug delivery because it results in the close proximity of drug-carrying particles to the endothelium, where they can easily diffuse into cancerous tumors through the leaky vasculature. Understanding the fundamentals of margination may further lead to the rational design of particles and allow for more specific delivery of anticancer drugs into tumors, thereby increasing patient comfort during cancer treatment. This paper reviews existing theoretical and experimental studies that focus on understanding margination. Margination is a complex phenomenon that depends on the interplay between inertial, hydrodynamic, electrostatic, lift, van der Waals, and Brownian forces. Parameters that have been explored thus far include the particle size, shape, density, stiffness, shear rate, and the concentration and aggregation state of red blood cells (RBCs). Many studies suggested that there exists an optimal particle size for margination to occur, and that nonspherical particles tend to marginate better than spherical particles. There are, however, conflicting views on the effects of particle density, stiffness, shear rate, and RBCs. The limitations of using the adhesion of particles to the channel walls in order to quantify margination propensity are explained, and some outstanding questions for future research are highlighted. PMID:24687242

  9. The Role of Intragroup Marginalization in Latino College Student Adjustment

    ERIC Educational Resources Information Center

    Castillo, Linda G.

    2009-01-01

    The purpose of this article is to examine how intragroup marginalization has a potential impact on Latino college students' psychological adjustment. The concept of intragroup marginalization in this context relates to the perceived rejection of students by persons of their heritage culture group in response to the students' acculturation efforts…

  10. Becoming Marginalized in a Middle School Physical Education Class.

    ERIC Educational Resources Information Center

    Smith, Barbara Tyree; Goc-Karp, Grace

    This study examined the effects of social competence, group formation, and group behavior on the marginalization of students in a 7th-grade physical education setting. Marginalized students are defined as those in the class, but not "of" the class. In addition, factors such as individual and team activity and teacher expectations help to explore…

  11. Marginal Pricing and Student Investment in Higher Education

    ERIC Educational Resources Information Center

    Hemelt, Steven W.; Stange, Kevin M.

    2016-01-01

    This paper examines the effect of marginal price on students' educational investments using rich administrative data on students at Michigan public universities. Marginal price refers to the amount colleges charge for each additional credit taken in a semester. Institutions differ in how they price credits above the full-time minimum (of 12…

  12. Helping Students on the Margin Succeed in Schools.

    ERIC Educational Resources Information Center

    Langenfeld, Michelle Schoen; Cumming, Brenda

    1996-01-01

    Addresses how Apple Valley High School (Minnesota) has been able to help marginal students succeed in school. The fundamental actions that contributed to the effectiveness of study-team efforts to help marginal students are discussed, and what has been learned through these efforts is considered. (GR)

  13. Coping with Marginalized Students Inclusion in EL Teacher Training

    ERIC Educational Resources Information Center

    Petkovska, Viktorija

    2015-01-01

    Marginalized groups present part of our reality which we would prefer to forget about. Yet, the humankind remains (un)aware of the simple fact that there is merely a very tiny red line between the central and marginalized parts: any of us can at one point in life simply, unwillingly and abruptly wake up on the other side of this line!!!…

  14. Managing Marginal School Employees: Applying Standards-Based Performance Measures

    ERIC Educational Resources Information Center

    Fields, Lynette; Reck, Brianne; Egley, Robert

    2006-01-01

    This book contains a collection of case studies that provide a variety of situations in managing or working with marginal employees in a school system. Managing Marginal School Employees will serve as a primary or companion text for administrator candidates or current administrators that include dilemmas for the student to think about, discuss,…

  15. Assessment of Biomass Resources from Marginal Lands in APEC Economies

    SciTech Connect

    Milbrandt, A.; Overend, R. P.

    2009-08-01

    The goal of this study is to examine the marginal lands in Asia-Pacific Economic Cooperation (APEC) economies and evaluate their biomass productivity potential. Twelve categories of marginal lands are identified using the Global Agro-Ecological Zones system of the United Nations Food and Agriculture Organization.

  16. Lorna Dee Cervantes: A Writer in the Margins.

    ERIC Educational Resources Information Center

    Connelly, Colette

    Chicana literary authors are sometimes thought to occupy the edges of two "texts," their own culture and the Anglo-American hegemony, where they are oppressed and marginalized by sexism and racism. In these margins, however, Chicana authors can dismantle stereotypes and construct new and empowering images of self. As an example of this kind of…

  17. Soil properties following reforestation or afforestation of marginal cropland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Reforestation or afforestation of marginal agricultural lands offers opportunities to sequester soil organic carbon (SOC) and improve the quality of degraded soils. The objectives of this study were to identify the extent and distribution of marginally productive cropland that was originally under f...

  18. Structure of the North American Atlantic Continental Margin.

    ERIC Educational Resources Information Center

    Klitgord, K. K.; Schlee, J. S.

    1986-01-01

    Offers explanations on the origin of the North American Atlantic continental margin. Provides an analysis and illustrations of structural and strategraphic elements of cross sections of the Atlantic continental margin. Also explains the operations and applications of seismic-relection profiles in studying ocean areas. (ML)

  19. Factors controlling structural style and magmatism in passive margins

    NASA Astrophysics Data System (ADS)

    Lu, Gang; Huismans, Ritske S.

    2015-04-01

    Comparing volcanic and non-volcanic passive margins, the distinct variability in geometry and subsidence history implies that the thermo-mechanical conditions vary at the time of rifting. Volcanic rifted margins (such as in the North Atlantic) show large magmatic activity and shallow water condition at the rift-drift transition, implying high geothermal gradients. For non-volcanic rifted margins where the initial thermal condition is potentially colder, it may develop in two end-member styles (Type I and Type II). Type-I margin with limited magmatism can be observed at Iberia-Newfoundland conjugate margins where the continental crustal thins across a narrow region and large tracts of continental mantle lithosphere are exposed at the seafloor. Type-II margin as observed in the ultra-wide central South Atlantic margins, in contrast, has normal magmatic activity and has a strongly thinned continental crust that span very wide regions (>250 km) below which the continental mantle lithosphere was removed. Here we perform thermo-mechanical finite element numerical experiments to investigate factors that are potentially important for the formation of volcanic and non-volcanic passive margins. Forward numerical models are used to predict the structural styles and characteristic magmatism associated with each of these end members. A number of parameters including different rheological stratifications and thermal gradients are tested and factors that control the degree of magmatism and structural style during rifting are focused.

  20. How to make offshore marginal fields work for everyone

    SciTech Connect

    Blandford, P.R.

    1995-12-31

    Marginal fields make positive impact on certain oil and gas companies` financial performances. These developments are integrated into the operator`s operational and philosophical mindset, so that they optimize return and establish a reasonable reserve base for the company. Having a portfolio of marginal field developments is definitely a part of the offshore business, and oil field suppliers and subcontractors will continue to develop technology and methods to ensure the fields are exploited. It goes without saying that the continued production of marginal fields helps a lot of consumers and the companies that make up the energy chain that gets it to them. There are marginal fields all over the world and the market can only grow as more and more of the resources decline and industrialization expands demand. The projections for 2020 state that fossil fuels will remain the major supply link to dependable and affordable energy, particularly as additional oil and gas infrastructures are built and installed. Likened to the commodity, oil and gas companies and the energy industry have slowly evolved to the point where they are making a difference for people worldwide. As long as there is product to produce, most companies and consumers do not really care what type of reservoir started it all. More often then not, it probably started out as a marginal prospect. The paper discusses the energy picture today, marginal field update, offshore marginal field geography, and independent and marginal field developments.