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

PubMed

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.

Intraoperative ultrasound control of surgical margins during partial nephrectomy.

PubMed

Alharbi, Feras M; Chahwan, Charles K; Le Gal, Sophie G; Guleryuz, Kerem M; Tillou, Xavier P; Doerfler, Arnaud P

2016-01-01

To evaluate a simple and fast technique to ensure negative surgical margins on partial nephrectomies, while correlating margin statuses with the final pathology report. This study was conducted for patients undergoing partial nephrectomy (PN) with T1-T2 renal tumors from January 2010 to the end of December 2015. Before tumor removal, intraoperative ultrasound (US) localization was performed. After tumor removal and before performing hemostasis of the kidney, the specimens were placed in a saline solution and a US was performed to evaluate if the tumor's capsule were intact, and then compared to the final pathology results. In 177 PN(s) (147 open procedures and 30 laparoscopic procedures) were performed on 147 patients. Arterial clamping was done for 32 patients and the mean warm ischemia time was 19 ± 6 min. The mean US examination time was 41 ± 7 s. The US analysis of surgical margins was negative in 172 cases, positive in four, and in only one case it was not possible to conclude. The final pathology results revealed one false positive surgical margin and one false negative surgical margin, while all other margins were in concert with US results. The mean tumor size was 3.53 ± 1.43 cm, and the mean surgical margin was 2.8 ± 1.5 mm. The intraoperative US control of resection margins in PN is a simple, efficient, and effective method for ensuring negative surgical margins with a small increase in warm ischemia time and can be conducted by the operating urologist.

Relationships between meaning in life, social and achievement events, and positive and negative affect in daily life.

PubMed

Machell, Kyla A; Kashdan, Todd B; Short, Jerome L; Nezlek, John B

2015-06-01

Research on meaning in life has generally focused on global meaning judgments. This study examined how people's daily experiences, represented by events that occur in daily life, influence their perceived sense of meaning on a daily basis. One hundred sixty-two college students completed daily reports for 2 weeks. We examined the relationships among daily social and achievement events, daily positive and negative affect, and daily meaning in life. In addition, we tested the possible moderating influence of depressive symptoms on these relationships. Positive daily social and achievement events were related to greater daily meaning, above and beyond the contributions of daily positive and negative affect. Negative social and achievement events were related to less daily meaning, and negative achievement events covaried with daily meaning above and beyond positive and negative affect. Depression moderated the relationships between positive events and meaning, such that people who reported more depressive symptoms had greater increases in daily meaning in response to positive social and achievement events than individuals who reported fewer symptoms. These findings suggest the important role that daily events may play in fluctuations in people's affective experiences and sense of meaning in life. © 2014 Wiley Periodicals, Inc.

Participation, Financial Support and the Marginal Student

ERIC Educational Resources Information Center

Davies, Peter; Mangan, Jean; Hughes, Amanda

2009-01-01

This paper examines differences between the decision-making of marginal and nonmarginal students about participation in higher education (HE). We distinguish between two kinds of marginality: being "borderline" on account of prior achievements in school and being "unsure" after taking prior achievement into account. We identify a significant…

Tumor response and negative distal resection margins of rectal cancer after hyperthermochemoradiation therapy.

PubMed

Tsutsumi, Soichi; Tabe, Yuichi; Fujii, Takaaki; Yamaguchi, Satoru; Suto, Toshinaga; Yajima, Reina; Morita, Hiroki; Kato, Toshihide; Shioya, Mariko; Saito, Jun-Ichi; Asao, Takayuki; Nakano, Takashi; Kuwano, Hiroyuki

2011-11-01

The safety of regional hyperthermia has been tested in locally advanced rectal cancer. The aim of this study was to assess the effects of shorter distal margins on local control and survival in rectal cancer patients who were treated with preoperative hyperthermochemoradiation therapy (HCRT) and underwent rectal resection by using the total mesorectal excision (TME) method. Ninety-three patients with rectal adenocarcinoma who received neoadjuvant HCRT (total radiation: 50 Gy) were included in this study. Surgery was performed 8 weeks after HCRT, and each resected specimen was evaluated histologically. Length of distal surgical margins, status of circumferential margins, pathological response, and tumor node metastasis stage were examined for their effects on recurrence and survival. Fifty-eight (62.4%) patients had tumor regression, and 20 (21.5%) had a pathological complete response. Distal margin length ranged from 1 to 55 mm (median, 21 mm) and did not correlate with local recurrence (p=0.57) or survival (p=0.75) by univariate analysis. Kaplan-Meier estimates of recurrence-free survival and local recurrence for the <10 mm versus ≥10 mm groups were not significantly different. Positive circumferential margins and failure of tumors to respond were unfavorable factors in survival. Distal resection margins that are shorter than 10 mm but are not positive appear to be equivalent to longer margins in patients who undergo HCRT followed by rectal resection with TME. To improve the down-staging rate, additional studies are needed.

Understanding the Role of Negative Emotions in Adult Learning and Achievement: A Social Functional Perspective

PubMed Central

Fitness, Julie

2018-01-01

The role of emotions in adult learning and achievement has received increasing attention in recent years. However, much of the emphasis has been on test anxiety, rather than the wider spectrum of negative emotions such as sadness, grief, boredom and anger. This paper reports findings of a qualitative study exploring the experience and functionality of negative emotions at university. Thirty-six academic staff and students from an Australian university were interviewed about emotional responses to a range of learning events. Data analysis was informed by a prototype approach to emotion research. Four categories of discrete negative emotions (anger, sadness, fear, boredom) were considered by teachers and students to be especially salient in learning, with self-conscious emotions (guilt, embarrassment, shame) mentioned by more students than staff. While negative emotions were frequently viewed as detrimental to motivation, performance and learning, they were also construed under some circumstances as beneficial. The findings are discussed in relation to the value of social functional approaches for a better understanding of the diverse roles of negative emotions in learning and achievement. PMID:29461487

Understanding the Role of Negative Emotions in Adult Learning and Achievement: A Social Functional Perspective.

PubMed

Rowe, Anna D; Fitness, Julie

2018-02-20

The role of emotions in adult learning and achievement has received increasing attention in recent years. However, much of the emphasis has been on test anxiety, rather than the wider spectrum of negative emotions such as sadness, grief, boredom and anger. This paper reports findings of a qualitative study exploring the experience and functionality of negative emotions at university. Thirty-six academic staff and students from an Australian university were interviewed about emotional responses to a range of learning events. Data analysis was informed by a prototype approach to emotion research. Four categories of discrete negative emotions (anger, sadness, fear, boredom) were considered by teachers and students to be especially salient in learning, with self-conscious emotions (guilt, embarrassment, shame) mentioned by more students than staff. While negative emotions were frequently viewed as detrimental to motivation, performance and learning, they were also construed under some circumstances as beneficial. The findings are discussed in relation to the value of social functional approaches for a better understanding of the diverse roles of negative emotions in learning and achievement.

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

PubMed

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.

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

A novel approach emphasising intra-operative superficial margin enhancement of head-neck tumours with narrow-band imaging in transoral robotic surgery.

PubMed

Vicini, C; Montevecchi, F; D'Agostino, G; DE Vito, A; Meccariello, G

2015-06-01

The primary goal of surgical oncology is to obtain a tumour resection with disease-free margins. Transoral robotic surgery (TORS) for surgical treatment of head-neck cancer is commensurate with standard treatments. However, the likelihood of positive margins after TORS is up to 20.2% in a recent US survey. The aim of this study is to evaluate the efficacy and the feasibility of narrow-band imaging (NBI) during TORS in order to improve the ability to achieve disease-free margins during tumour excision. The present study was conducted at the ENT, Head- Neck Surgery and Oral Surgery Unit, Department of Special Surgery, Morgagni Pierantoni Hospital, Azienda USL Romagna. From March 2008 to January 2015, 333 TORS were carried out for malignant and benign diseases. For the present study, we retrospectively evaluated 58 biopsy-proven squamous cell carcinoma patients who underwent TORS procedures. Patients were divided into 2 groups: (1) 32 who underwent TORS and intra-operative NBI evaluation (NBI-TORS); (2) 21 who underwent TORS with standard intra-operative white-light imaging (WLITORS). Frozen section analysis of margins on surgical specimens showed a higher rate of negative superficial lateral margins in the NBI-TORS group compared with the WLI-TORS group (87.9% vs. 57.9%, respectively, p = 0.02). The sensitivity and specificity of intra-operative use of NBI, respectively, were 72.5% and 66.7% with a negative predictive value of 87.9%. Tumour margin enhancement provided by NBI associated with magnification and 3-dimensional view of the surgical field might increase the capability to achieve an oncologically-safe resection in challenging anatomical areas where minimal curative resection is strongly recommended for function preservation.

[Resection margins in conservative breast cancer surgery].

PubMed

Medina Fernández, Francisco Javier; Ayllón Terán, María Dolores; Lombardo Galera, María Sagrario; Rioja Torres, Pilar; Bascuñana Estudillo, Guillermo; Rufián Peña, Sebastián

2013-01-01

Conservative breast cancer surgery is facing a new problem: the potential tumour involvement of resection margins. This eventuality has been closely and negatively associated with disease-free survival. Various factors may influence the likelihood of margins being affected, mostly related to the characteristics of the tumour, patient or surgical technique. In the last decade, many studies have attempted to find predictive factors for margin involvement. However, it is currently the new techniques used in the study of margins and tumour localisation that are significantly reducing reoperations in conservative breast cancer surgery. Copyright © 2012 AEC. Published by Elsevier Espana. All rights reserved.

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…

An Integrative Cultural Model to better situate marginalized science students in postsecondary science education

NASA Astrophysics Data System (ADS)

Labouta, Hagar Ibrahim; Adams, Jennifer Dawn; Cramb, David Thomas

2018-03-01

In this paper we reflect on the article "I am smart enough to study postsecondary science: a critical discourse analysis of latecomers' identity construction in an online forum", by Phoebe Jackson and Gale Seiler (Cult Stud Sci Educ. https://doi.org/10.1007/s11422-017-9818-0). In their article, the authors did a significant amount of qualitative analysis of a discussion on an online forum by four latecomer students with past negative experiences in science education. The students used this online forum as an out-of-class resource to develop a cultural model based on their ability to ask questions together with solidarity as a new optimistic way to position themselves in science. In this forum, we continue by discussing the identity of marginalized science students in relation to resources available in postsecondary science classes. Recent findings on a successful case of a persistent marginalized science student in spite of prior struggles and failures are introduced. Building on their model and our results, we proposed a new cultural model, emphasizing interaction between inside and outside classroom resources which can further our understanding of the identity of marginalized science students. Exploring this cultural model could better explain drop-outs or engagement of marginalized science students to their study. We, then, used this model to reflect on both current traditional and effective teaching and learning practices truncating or re-enforcing relationships of marginalized students with the learning environment. In this way, we aim to further the discussion initiated by Jackson and Seiler and offer possible frameworks for future research on the interactions between marginalized students with past low achievements and other high and mid achieving students, as well as other interactions between resources inside and outside science postsecondary classrooms.

A Classroom Game on a Negative Externality Correcting Tax: Revenue Return, Regressivity, and the Double Dividend

ERIC Educational Resources Information Center

Duke, Joshua M.; Sassoon, David M.

2017-01-01

The concept of negative externality is central to the teaching of environmental economics, but corrective taxes are almost always regressive. How exactly might governments return externality-correcting tax revenue to overcome regressivity and not alter marginal incentives? In addition, there is a desire to achieve a double dividend in the use of…

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

Role of specimen US for predicting resection margin status in breast conserving therapy.

PubMed

Moschetta, M; Telegrafo, M; Introna, T; Coi, L; Rella, L; Ranieri, V; Cirili, A; Stabile Ianora, A A; Angelelli, G

2015-01-01

To assess the diagnostic accuracy of specimen ultrasound (US) for predicting resection margin status in women undergoing breast conserving therapy for US-detected cancer, having the histological findings as the reference standard. A total of 132 consecutive patients (age range, 34-87 years; mean, 51 years) underwent breast-conserving surgery for US-detected invasive breast cancer. All surgical specimens underwent US examination. The presence of lesion within the specimen and its distance from the specimen margins were assessed considering a threshold distance between the lesion and specimen margins of 10 mm. US findings were then compared with the pathological ones and specimen US. Sensitivity, specificity, diagnostic accuracy, positive (PPV) and negative predictive values (NPV) for predicting histological margin status were evaluated, having the histological findings as the reference standard. The histological examination detected invasive ductal carcinoma in 96/132 (73%) cases, invasive lobular carcinoma in 32/132 (24%), mucinous carcinoma in 4/132 (3%). The pathological margin analysis revealed 96/132 (73%) negative margins and 36 (27%) close/positive margins. US examination detected all 132 breast lesions within the surgical specimens. 110 (83%) negative margins and 22 (17%) positive margins were found on US. Sensitivity, specificity, diagnostic accuracy, PPV and NPV of 44%, 94%, 80%, 73% and 82%, respectively, were found for specimen US. Specimen US represents a time and cost saving imaging tool for evaluating the presence of US detected-breast lesion within surgical specimen and for predicting the histological margin status.

Whipple Resection: Concordance Between Frozen Section And Permanent Section Diagnosis Of Surgical Margins.

PubMed

Bilal, Muhammad; Tariq, Hina; Mamoon, Nadira

2018-01-01

Margin assessment is done in Whipple procedures which are usually performed to resect tumours of head of pancreas and ampullary/periampullary region. Aims and objective of the study are to determine the concordance between frozen sections (FS) and permanent sections (PS) of surgical margins in Whipple resections. It is a retrospective study, from January 2008 to January 2015 (07 years). It includes the specimen with malignancy in final report and for which FS of pancreatic and/or CBD margin(s) were requested. Data was retrieved from Laboratory information system (LIS) database. Of the 41 bile duct margins in cases of ampullary tumours, 03 were positive on FS as well as PS, 35 were negative on FS as well as on PS. Results showed 100% sensitivity, 92.1% specificity, 50% PPV and 100% NPV. Results of 36 pancreatic margins in cases of ampullary showed 100% sensitivity, 97.1% specificity, 50% PPV and 100% NPV. In pancreatic carcinoma cases, none of CBD margins were reported as positive on FS, 02 margins reported as negative were found positive on PS, while 17 were negative on FS as well as PS. Results showed 100% specificity and 89.5% NPV. Of the 27 pancreatic margins tested in pancreatic tumours 100% sensitivity, 94.1% specificity, 88.9% PPV and 100% NPV was found. Factors such as absent prior tissue diagnosis and/or inflammatory processes make margin diagnosis difficult. However, a high concordance was observed between our FS and PS diagnosis.

Partial nephrectomy for renal tumors: lack of correlation between margin status and local recurrence.

PubMed

Antic, Tatjana; Taxy, Jerome B

2015-05-01

To evaluate the relationship between a positive resection margin in partial nephrectomy (PN) and local recurrence. From January 2005 through December 2012, there were 473 PNs in 466 patients at the University of Chicago. A positive margin was defined as tumor extending to the inked specimen edge, either the parenchymal interface or the peripheral fibroadipose tissue. A local recurrence was defined as an ipsilateral tumor of identical histologic type. Renal cell carcinoma (RCC) accounted for 406 tumors: 243 clear cell RCCs (CRCCs), 77 papillary RCCs (PRCCs), and 47 chromophobe RCCs (CHRCCs). Sixty-one RCCs had positive margins: 43 CRCCs, six PRCCs, nine CHRCCs, and three miscellaneous cell types. Of the 61 positive margins, four CRCCs (all originally multifocal) had a local recurrence, two of which occurred in the same patient. One translocation RCC also recurred. Six cases with negative resection margins had a recurrence. A literature review of 3,803 cases, including our study, shows positive margins in 173, of which 13 recurred; however, 39 with negative margins also recurred. A positive margin in PN seldom correlates with a local recurrence. However, protection from recurrence is not ensured by a negative margin. Copyright© by the American Society for Clinical Pathology.

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

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

PubMed

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

2016-06-01

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. 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. 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). 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.

Role of specimen US for predicting resection margin status in breast conserving therapy

PubMed Central

MOSCHETTA, M.; TELEGRAFO, M.; INTRONA, T.; COI, L.; RELLA, L.; RANIERI, V.; CIRILLI, A.; IANORA, A.A. STABILE; ANGELELLI, G.

2015-01-01

Aim To assess the diagnostic accuracy of specimen ultrasound (US) for predicting resection margin status in women undergoing breast conserving therapy for US-detected cancer, having the histological findings as the reference standard. Patients and methods A total of 132 consecutive patients (age range, 34–87 years; mean, 51 years) underwent breast-conserving surgery for US-detected invasive breast cancer. All surgical specimens underwent US examination. The presence of lesion within the specimen and its distance from the specimen margins were assessed considering a threshold distance between the lesion and specimen margins of 10 mm. US findings were then compared with the pathological ones and specimen US. Sensitivity, specificity, diagnostic accuracy, positive (PPV) and negative predictive values (NPV) for predicting histological margin status were evaluated, having the histological findings as the reference standard. Results The histological examination detected invasive ductal carcinoma in 96/132 (73%) cases, invasive lobular carcinoma in 32/132 (24%), mucinous carcinoma in 4/132 (3%). The pathological margin analysis revealed 96/132 (73%) negative margins and 36 (27%) close/positive margins. US examination detected all 132 breast lesions within the surgical specimens. 110 (83%) negative margins and 22 (17%) positive margins were found on US. Sensitivity, specificity, diagnostic accuracy, PPV and NPV of 44%, 94%, 80%, 73% and 82%, respectively, were found for specimen US. Conclusions Specimen US represents a time and cost saving imaging tool for evaluating the presence of US detected-breast lesion within surgical specimen and for predicting the histological margin status. PMID:26712255

Intra-surgical total and re-constructible pathological prostate examination for safer margins and nerve preservation (Istanbul preserve).

PubMed

Öbek, Can; Saglican, Yesim; Ince, Umit; Argun, Omer Burak; Tuna, Mustafa Bilal; Doganca, Tunkut; Tufek, Ilter; Keskin, Selcuk; Kural, Ali Riza

2018-04-01

To demonstrate a novel frozen section analysis technique during robot assisted radical prostatectomy with 2 distinct advantages: evaluation of the entire circumference and easier reconstruction for whole mount evaluation. Istanbul Preserve was performed on patients who underwent robotic prostatectomy with nerve sparing between 10/2014 and 7/2016. Gland was sectioned at 3-4mm intervals from apex to bladder neck. Entire tissue representing margins (except for the most anterior portion) was circumferentially excised and microscopically analyzed. In margin positivity, approach was individualized based on extent of positive margin and Gleason pattern. A matched cohort was established for comparison. Retrospective analysis of a prospectively maintained database was performed. Impact of FSA on PSM rate was primarily assessed. Data on 170 patients was analyzed. Positive surgical margin was reported in 56(33%) on frozen section. Neurovascular bundle was partially or totally resected in 79% and 18%. Conversion of positive margin to negative was achieved in 85%. Overall positive margin rate decreased from 22.5% to 7.5%. Nerve sparing increased from 87% to 93%. Location of positive margin at frozen was at the neurovascular bundle area in 39%; thus Istanbul Preserve detected 61% additional margin positivity compared to other techniques. Reconstruction for whole mount was easy. Istanbul Preserve is a novel technique for intraoperative FSA during RARP allowing for microscopic examination of the entire prostate for margin status and easy re-construction for whole mount examination. It guarantees safer margins together with increased rate of nerve sparing. Copyright © 2017 Elsevier Inc. All rights reserved.

Safety margins in the implementation of planetary quarantine requirements

NASA Technical Reports Server (NTRS)

Schalkowsky, S.; Jacoby, I.

1972-01-01

The formulation of planetary quarantine requirements, and their implementation as determined by a risk allocation model, is discussed. The model defines control safety margins with particular emphasis on utility in achieving the desired minimization of excessive margins, and their effect on implementation procedures.

Defining the surgical margins of adenoid cystic carcinoma and their impact on outcome: An international collaborative study.

PubMed

Amit, Moran; Na'ara, Shorook; Trejo-Leider, Leonor; Ramer, Naomi; Burstein, David; Yue, Ma; Miles, Brett; Yang, Xinjie; Lei, Delin; Bjoerndal, Kristine; Godballe, Christian; Mücke, Thomas; Wolff, Klaus-Dietrich; Eckardt, André M; Copelli, Chiara; Sesenna, Enrico; Patel, Snehal; Ganly, Ian; Gil, Ziv

2017-05-01

The mainstay of treatment in adenoid cystic carcinoma (ACC) of the head and neck is surgical resection with negative margins. The purpose of this study was to define the margin status that associates with survival outcomes of ACC of the head and neck. We conducted univariate and multivariate analyses of international data. Data of 507 patients with ACC of the head and neck were analyzed; negative margins defined as ≥5 mm were detected in 253 patients (50%). On multivariate analysis, the hazard ratios (HRs) of positive margin status were 2.68 (95% confidence interval [CI], 1.2-6.2; p = .04) and 2.63 (95% CI, 1.1-6.3; p = .03) for overall survival (OS) and disease-specific survival (DSS), respectively. Close margins had no significant impact on outcome, with HRs of 1.1 (95% CI, 0.4-3.0; p = .12) and 1.07 (95% CI, 0.3-3.4; p = .23) for OS and DSS, respectively, relative with negative margins. In head and neck ACC, positive margins are associated with the worst outcome. Negative or close margins are associated with improved outcome, regardless of the distance from the tumor. © 2017 Wiley Periodicals, Inc. Head Neck 39: 1008-1014, 2017. © 2017 Wiley Periodicals, Inc.

Concordance of gross surgical and final fixed margins in vulvar intraepithelial neoplasia 3 and vulvar cancer.

PubMed

DeSimone, Christopher P; Crisp, Meredith P; Ueland, Frederick R; DePriest, Paul D; van Nagell, John R; Lele, Subodh M; Modesitt, Susan C

2006-08-01

To prospectively evaluate the concordance of initial surgical vulvar margins and final fixed margins and to determine the amount of microscopic pathology of grossly negative margins in women with vulvar intraepithelial neoplasia (VIN) 3 or vulvar carcinoma. Women with VIN 3 or vulvar carcinoma undergoing surgical excision were identified. Prior to excision, acetic acid was used to highlight the lesions, and 2 sutures were placed, 1 at the edge of gross disease and another 1 cm distal from the first. After specimen removal and fixation, the distance between sutures and microscopic involvement of VIN was determined. Twenty-seven women were enrolled; however, only 19 had final fixed specimens that could be accurately measured. The median fixed distance of the vulvar margin was 0.85 cm (mean, 0.83; SD, 0.19) as compared to the gross, 1-cm margin (p = 0.001). Three subjects (16%) had microscopic involvement by VIN 3 in the grossly negative epithelium between the 2 sutures, but none had a positive peripheral margin. The gross surgical margin after vulvar resection is reduced by 15% when measured in its final fixed state, and a grossly negative 1-cm margin will seldom harbor significant disease.

Informing practice regarding marginalization: the application of the Koci Marginality Index.

PubMed

Koci, Anne Floyd; McFarlane, Judith; Nava, Angeles; Gilroy, Heidi; Maddoux, John

2012-12-01

The 49th World Health Assembly of the World Health Organization (WHO) declared violence as the leading worldwide public health problem with a focus on the increase in the incidence of injuries to women. Violence against women is an international epidemic with specific instruments required to measure the impact on women's functioning. This article describes the application of the Koci Marginality Index (KMI), a 5-item scale to measure marginality, to the baseline data of a seven-year prospective study of 300 abused women: 150 first time users of a shelter and 150 first time applicants for a protection order from the justice system. Validity and reliability of the Koci Marginality Index and its usefulness for best clinical practice and for policy decisions for abused women's health are discussed. The 49th World Health Assembly of the World Health Organization (WHO) declared violence as the leading worldwide public health problem and focused on the increase in the incidence of injuries to women (Krug et al., 2002 ). Violence against women in the form of intimate partner violence (IPV) is costly in terms of dollars and health. In the United States in 2003, estimated costs of IPV approached $8.3 billion (Centers for Disease Control and Prevention [CDC], 2011). Outcomes related to severity of IPV vary but in 2003 victims suffering severe IPV lost nearly 8 million days of paid work, and greater than 5 million days of household productivity annually (CDC, 2011). Besides the evident financial cost of IPV, research confirms that exposure to IPV impacts a woman's health immediately and in the long-term (Breiding, Black, & Ryan, 2008 ; Campbell, 2002 ; CDC, 2011). Such sequela adversely affect the health of women and may increase their marginalization, a concept akin to isolation that may further increase negative effects on health outcomes. Immigrant women are at high risk for IPV (Erez, 2002 ) and those without documentation are at higher risk for marginalization (Montalvo

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

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

PubMed Central

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

2015-01-01

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 phosphatidylethanolamine N-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, R2 = 0.285). With the addition of the PEMT rs12325817 polymorphism, the association value was only marginally changed. Plasma betaine concentration, tHcy, and the MTHFR 677C>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

Real-time transrectal ultrasound guidance during laparoscopic radical prostatectomy: impact on surgical margins.

PubMed

Ukimura, Osamu; Magi-Galluzzi, Cristina; Gill, Inderbir S

2006-04-01

We evaluated whether intraoperative real-time TRUS navigation during LRP can decrease the incidence of positive surgical margins. Since March 2001, 294 patients with clinically organ confined prostate cancer undergoing LRP have been retrospectively divided into 2 groups, including group 1-217 who underwent LRP without TRUS from March 2001 to February 2003 and group 2-77 who have undergone LRP with TRUS since March 2003. Various baseline parameters were similar between the groups. Before March 2001 the senior surgeon had already performed more than 50 cases of LRP, thus, gaining reasonable familiarity with the technique. Compared to group 1, group 2 had a significantly decreased rate of positive surgical margins in patients with pT3 disease (57% vs 18%, p = 0.002). Positive margin rates also decreased in our overall experience (29% vs 9%, p = 0.0002). Intraoperative TRUS correctly predicted pT2 and pT3 disease in 85% and 86% of patients, respectively. Of the 54 TRUS visualized hypoechoic lesions at sites corresponding to biopsy proven cancer extracapsular extension was suspected in 31, leading to a real-time recommendation of calibrated wider, site specific dissection to achieve negative surgical margins. Intraoperative TRUS monitoring during LRP allows individualized, precise dissection tailored to the specific prostate contour anatomy, thus, compensating for the muted tactile feedback of laparoscopy. In what is to our knowledge the initial experience real-time TRUS guidance significantly decreased the incidence of positive surgical margins during LRP. In the future this concept of rectum based, intraoperative real-time navigation may facilitate a more sophisticated performance of radical prostatectomy.

Length of positive surgical margin after radical prostatectomy as a predictor of biochemical recurrence.

PubMed

Shikanov, Sergey; Song, Jie; Royce, Cassandra; Al-Ahmadie, Hikmat; Zorn, Kevin; Steinberg, Gary; Zagaja, Gregory; Shalhav, Arieh; Eggener, Scott

2009-07-01

Length and location of positive surgical margins are independent predictors of biochemical recurrence after open radical prostatectomy. We assessed their impact on biochemical recurrence in a large robotic prostatectomy series. Data were collected prospectively from 1,398 men undergoing robotic radical prostatectomy for clinically localized prostate cancer from 2003 to 2008 at a single institution. The associations of preoperative prostate specific antigen, pathological Gleason score, pathological stage and positive surgical margin parameters (location, length and focality) with biochemical recurrence rate were evaluated. Margin status and length were measured by a single uropathologist. Biochemical recurrence was defined as serum prostate specific antigen greater than 0.1 ng/ml on 2 consecutive tests. Cox regression models were constructed to evaluate predictors of biochemical recurrence. Of 1,398 consecutive patients who underwent robotic prostatectomy positive margins were present in 243 (17%) (11% of pathological T2 and 41% of T3). Preoperative prostate specific antigen, pathological stage, Gleason score, margin status, and margin length as a continuous and categorical variable (less than 1, 1 to 3, more than 3 mm) were independent predictors of biochemical recurrence. Patients with negative margins and those with a positive margin less than 1 mm had similar rates of biochemical recurrence (log rank test p = 0.18). Surgical margin location was not independently associated with biochemical recurrence. Margin status and length are independent predictors of biochemical recurrence following robotic radical prostatectomy. Although longer followup and validation studies are necessary for confirmation, patients with a positive margin less than 1 mm appear to have similar recurrence rates as those with negative margins.

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

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

Patel, R; Block, A; Harkenrider, M

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,more » 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.« less

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. © 2014 The Authors. Child Development © 2014 Society for Research in Child Development, Inc.

Positive surgical margins in robot-assisted partial nephrectomy: a multi-institutional analysis of oncologic outcomes (leave no tumor behind).

PubMed

Khalifeh, Ali; Kaouk, Jihad H; Bhayani, Sam; Rogers, Craig; Stifelman, Michael; Tanagho, Youssef S; Kumar, Ramesh; Gorin, Michael A; Sivarajan, Ganesh; Samarasekera, Dinesh; Allaf, Mohamad E

2013-11-01

Expanding indications for robot-assisted partial nephrectomy raise major oncologic concerns for positive surgical margins. Previous reports showed no correlation between positive surgical margins and oncologic outcomes. We report a multi-institutional experience with the oncologic outcomes of positive surgical margins on robot-assisted partial nephrectomy. Pathological and clinical followup data were reviewed from an institutional review board approved, prospectively maintained joint database from 5 institutions. Tumors with malignant pathology were isolated and statistically analyzed for demographics and oncologic followup. The log rank test was used to compare recurrence-free and metastasis-free survival between patients with positive and negative surgical margins. The proportional hazards method was used to assess the influence of multiple factors, including positive surgical margins, on recurrence and metastasis. A total of 943 robot-assisted partial nephrectomies for malignant tumors were successfully completed. Of the patients 21 (2.2%) had positive surgical margins on final pathological assessment, resulting in 2 groups, including the 21 with positive surgical margins and 922 with negative surgical margins. Positive surgical margin cases had higher recurrence and metastasis rates (p<0.001). As projected by the Kaplan-Meier method in the population as a whole at followup out to 63.6 months, 5-year recurrence-free and metastasis-free survival was 94.8% and 97.5%, respectively. There was a statistically significant difference in recurrence-free and metastasis-free survival between patients with positive and negative surgical margins (log rank test<0.001), which favored negative surgical margins. Positive surgical margins showed an 18.4-fold higher HR for recurrence when adjusted for multiple tumors, tumor size, tumor growth pattern and pathological stage. Positive surgical margins on final pathological evaluation increase the HR of recurrence and metastasis. In

gp49B-mediated negative regulation of antibody production by memory and marginal zone B cells.

PubMed

Fukao, Saori; Haniuda, Kei; Nojima, Takuya; Takai, Toshiyuki; Kitamura, Daisuke

2014-07-15

The rapid Ab responses observed after primary and secondary immunizations are mainly derived from marginal zone (MZ) and memory B cells, respectively, but it is largely unknown how these responses are negatively regulated. Several inhibitory receptors have been identified and their roles have been studied, but mainly on follicular B cells and much less so on MZ B, and never on memory B cells. gp49B is an Ig superfamily member that contains two ITIMs in its cytoplasmic tail, and it has been shown to negatively regulate mast cell, macrophage, and NK cell responses. In this study, we demonstrate that gp49B is preferentially expressed on memory and MZ B cells. We show that gp49B(-/-) mice produce more IgM after a primary immunization and more IgM and IgG1 after a secondary immunization than gp49B(+/+) mice in T cell-dependent immune responses. Memory and MZ B cells from gp49B(-/-) mice also produce more Abs upon in vitro stimulation with CD40 than those from gp49B(+/+) mice. The in vitro IgM production by MZ B cells from gp49B(+/+), but not gp49B(-/-), mice is suppressed by interaction with a putative gp49B ligand, the integrin αvβ3 heterodimer. In addition, gp49B(-/-) mice exhibited exaggerated IgE production in the memory recall response. These results suggest that plasma cell development from memory and MZ B cells, as well as subsequent Ab production, are suppressed via gp49B. In memory B cells, this suppression also prevents excessive IgE production, thus curtailing allergic diseases. Copyright © 2014 by The American Association of Immunologists, Inc.

Resection margin and recurrence-free survival after liver resection of colorectal metastases.

PubMed

Muratore, Andrea; Ribero, Dario; Zimmitti, Giuseppe; Mellano, Alfredo; Langella, Serena; Capussotti, Lorenzo

2010-05-01

Optimal margin width is uncertain because of conflicting results from recent studies using overall survival as the end-point. After recurrence, re-resection and aggressive chemotherapy heavily affect survival time; the potential confounding effect of such factors has not been investigated. Use of recurrence-free survival (RFS) may overcome this limitation. The aim of this study is to evaluate the impact of width of resection margin on RFS and site of recurrence after hepatic resection for colorectal metastases (CRM). From a prospectively maintained institutional database (1/1999-12/2007) we identified 314 patients undergone hepatectomy for CRM (1/1999-12/2007) with detailed pathologic analysis of the surgical margin and complete follow-up imaging studies documenting disease status and site of recurrence, which was categorized as: resection margin (M(arg)), other intra-hepatic ((other)IH), lung (L) or other extra-hepatic ((other)EH). Recurrence-free estimation was the survival end-point. Median follow-up was 56.5 months. Two hundred and fifteen patients (68.8%) recurred at 288 sites after a mean of 15.5 months. A positive resection margin was associated with an increased risk of M(arg) recurrence (P < 0.001). The presence of >or=2 metastases was the only factor increasing the risk of positive margins (P < 0.05). The width of the negative resection margin (>or=1 cm versus >1 cm) was not a prognostic factor of worse RFS (30.2% versus 37.3%, P = 0.6). Node status of the primary tumour, and size and number of CRM were independent predictors of RFS. Tumour biology and not the width of the negative resection margin affect RFS.

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

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.

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

Examining the margins: a concept analysis of marginalization.

PubMed

Vasas, Elyssa B

2005-01-01

The aim of this analysis is to explore the concept of social marginalization for the purpose of concept development. Specifically, the article intends to clarify the relationship between health disparities and marginalization and generate knowledge about working with people who are socially marginalized. Concept development evolved from the critical analysis of relevant literature generated through searches of nursing and social science databases. Literature was organized thematically and themes related to marginalization as a social process were included and analyzed. The article explores the challenges of using marginalization as an independent concept and suggests areas for future inquiry and research.

Reinforcing marginality? Maternal health interventions in rural Nicaragua.

PubMed

Kvernflaten, Birgit

2017-06-23

To achieve Millennium Development Goal 5 on maternal health, many countries have focused on marginalized women who lack access to care. Promoting facility-based deliveries to ensure skilled birth attendance and emergency obstetric care has become a main measure for preventing maternal deaths, so women who opt for home births are often considered 'marginal' and in need of targeted intervention. Drawing upon ethnographic data from Nicaragua, this paper critically examines the concept of marginality in the context of official efforts to increase institutional delivery amongst the rural poor, and discusses lack of access to health services among women living in peripheral areas as a process of marginalization. The promotion of facility birth as the new norm, in turn, generates a process of 're-marginalization', whereby public health officials morally disapprove of women who give birth at home, viewing them as non-compliers and a problem to the system. In rural Nicaragua, there is a discrepancy between the public health norm and women's own preferences and desires for home birth. These women live at the margins also in spatial and societal terms, and must relate to a health system they find incapable of providing good, appropriate care. Strong public pressure for institutional delivery makes them feel distressed and pressured. Paradoxically then, the aim of including marginal groups in maternal health programmes engenders resistance to facility birth.

Marginal Maidens and Educational Policy for Women's Institutions.

ERIC Educational Resources Information Center

Connor, Kathleen M.

Unfavorable world and national economic and social trends of recent years have been paralleled by a reduced commitment to social services for marginalized peoples, including educational programs for women inmates. The potential negative results for future levels of delinquency and crime cannot be precisely calculated, according to sociologists and…

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. Copyright © 2016 Elsevier Ltd. All rights reserved.

Invasive vulvar carcinoma and the question of the surgical margin.

PubMed

Palaia, Innocenza; Bellati, Filippo; Calcagno, Marco; Musella, Angela; Perniola, Giorgia; Panici, Pierluigi B

2011-08-01

To assess the discrepancy between width of surgical margin measured with the naked eye/ruler by a surgeon before removing an invasive vulvar carcinoma, and width of margin measured under microscope by pathologist after fixation of the resected lesion with formalin. Potential relationships between discrepancy and disease recurrence were also investigated. This prospective study was conducted with resected lesions from 86 women who underwent surgery for primary/recurrent invasive vulvar carcinoma. After the surgeon removed the lesions surrounded by 1-2-cm margins, the pathologist determined margin width at the 4 cardinal points of 86 lesions (for a total of 344 margin assessments), first macroscopically and then under the microscope. A safety margin of 0.8 cm on microscopic view was achieved in 83% of cases (112 of 135) when the macroscopic measurement was 1cm, in 91% of cases (58 of 64) when it was 1.5 cm, and 98% of cases (105 of 107) when it was 2 cm. There was a small discrepancy between the surgeon's intent and the microscopic margin measurement, mostly related to tissue shrinkage. A 1-cm surgical margin corresponded to a 0.8-cm margin in microscopic view (the "safe margin") in most cases. Copyright © 2011 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

[Health expenditures, income inequality, and the marginalization index in Mexico's health system].

PubMed

Pinzón Florez, Carlos Eduardo; Reveiz, Ludovic; Idrovo, Alvaro J; Reyes Morales, Hortensia

2014-01-01

Evaluate the effect of the relationship among public health expenditures, income inequality, and the marginalization index on maternal and child mortality in Mexico, to determine the effect of these factors on health system performance from a technical efficiency perspective. An ecological study of 32 Mexican states. Correlations were estimated between maternal and infant mortality and public health expenditures in total per capita, federal per capita, and state per capita for the years 2000, 2005, and 2010 (Gini coefficient and marginalization index). Linear regressions were used to explore the association of these variables with health indicators in the state systems. Negative correlations were observed for the marginalization index and Gini coefficient with regard to life expectancy at birth (-0.62 and -0.28 respectively). Furthermore, there was a positive correlation of 0.59 between the marginalization index and infant mortality (P <0.05). Multiple linear regression models revealed a negative effect of the marginalization index and Gini coefficient on health out-comes. Federal funding had a positive effect on system performance in terms of health indicators. Health system reform in Mexico has had a positive impact on the country's health indicators; federal financial investment seems to be effective in this regard. Social determinants have an important effect on health system performance, and analysis using multisectoral and multidisciplinary approaches are needed in addressing them.

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.

Comparison of histologic margin status in low-grade cutaneous and subcutaneous canine mast cell tumours examined by radial and tangential sections.

PubMed

Dores, C B; Milovancev, M; Russell, D S

2018-03-01

Radial sections are widely used to estimate adequacy of excision in canine cutaneous mast cell tumours (MCTs); however, this sectioning technique estimates only a small fraction of total margin circumference. This study aimed to compare histologic margin status in grade II/low grade MCTs sectioned using both radial and tangential sectioning techniques. A total of 43 circumferential margins were evaluated from 21 different tumours. Margins were first sectioned radially, followed by tangential sections. Tissues were examined by routine histopathology. Tangential margin status differed in 10 of 43 (23.3%) margins compared with their initial status on radial section. Of 39 margins, 9 (23.1%) categorized as histologic tumour-free margin (HTFM) >0 mm were positive on tangential sectioning. Tangential sections detected a significantly higher proportion of positive margins relative to radial sections (exact 2-tailed P-value = .0215). The HTFM was significantly longer in negative tangential margins than positive tangential margins (mean 10.1 vs 3.2 mm; P = .0008). A receiver operating characteristic curve comparing HTFM and tangentially negative margins found an area under the curve of 0.83 (95% confidence interval: 0.71-0.96). Although correct classification peaked at the sixth cut-point of HTFM ≥1 mm, radial sections still incorrectly classified 50% of margins as lacking tumour cells. Radial sections had 100% specificity for predicting negative tangential margins at a cut-point of 10.9 mm. These data indicate that for low grade MCTs, HTFMs >0 mm should not be considered completely excised, particularly when HTFM is <10.9 mm. This will inform future studies that use HTFM and overall excisional status as dependent variables in multivariable prognostic models. © 2017 John Wiley & Sons Ltd.

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

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

Childs, Stephanie K.; Chen, Yu-Hui; Duggan, Margaret M.

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 ofmore » 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.« less

Metaphors and the Pejorative Framing of Marginalized Groups: Implications for Social Work Education

ERIC Educational Resources Information Center

O'Brien, Gerald V.

2009-01-01

Although the importance of metaphors is described in the social work literature, few articles or books in the profession have considered the role of metaphors in social policy, especially in providing a negative frame within which marginalized groups can be considered. This negative framing naturally supports aversive social policies designed to…

Effect of Margin Designs on the Marginal Adaptation of Zirconia Copings.

PubMed

Habib, Syed Rashid; Al Ajmi, Mohammed Ginan; Al Dhafyan, Mohammed; Jomah, Abdulrehman; Abualsaud, Haytham; Almashali, Mazen

2017-09-01

The aim of this in vitro study was to investigate the effect of Shoulder versus Chamfer margin design on the marginal adaptation of zirconia (Zr) copings. 40 extracted molar teeth were mounted in resin and prepared for zirconia crowns with two margin preparation designs (20=Shoulder and 20=Chamfer). The copings were manufactured by Cercon® (DeguDent GmbH, Germany) using the CAD/CAM system for each tooth. They were tried on each tooth, cemented, thermocycled, re-embedded in resin and were subsequently cross sectioned centrally into two equal mesial and distal halves. They were examined under electron microscope at 200 X magnification and the measurements were recorded at 5 predetermined points in micrometers (µm). The o verall mean marginal gap for the two groups was found to be 206.98+42.78µm with Shoulder margin design (Marginal Gap=199.50+40.72µm) having better adaptation compared to Chamfer (Marginal Gap=214.46+44.85µm). The independent-samples t-test showed a statistically non-significant difference (p=.113) between the means of marginal gap for Shoulder and Chamfer margin designs and the measurements were recorded at 5 predetermined points for the two groups. The Chamfer margin design appeared to offer the same adaptation results as the Shoulder margin design.

The Variability in Surgical Margin Reporting in Limb Salvage Surgery for Sarcoma

PubMed Central

Hoang, Kevin; Gao, Yubo; Miller, Benjamin J.

2015-01-01

Background Surgical margins are a standard reported measurement in tumor surgery that has implications for functional outcome, local control, and overall survival. There is no single accepted classification, and it is unclear what form or margin reporting predominates in the sarcoma literature. Methods We performed a PubMed literature search to identify articles that reported surgical margins and oncologic outcomes in limb salvage surgery for sarcoma from 1980 to 2013. We recorded the margin classification, specialty of the journal, specialty of the author, and location of the authors' institution. Results We found that 159/448 (35%) of articles included in the study did not report surgical margins. Of the 289 papers that did include data on margins, 160 (55%) of articles used Enneking's classification. There has been an increase over time in the proportion of articles reporting surgical margins by the residual tumor (R) classification and the proportion of articles reporting margins dichotomously as “positive” or “negative.” Conclusions We did not find a common method for reporting margins in the limb salvage sarcoma literature. Of most concern was over 1/3 of clinical reports of oncologic outcomes did not include margin status, which substantially compromises any conclusions that readers may infer about treatment success, local recurrence, or survival. We believe there should be renewed efforts to encourage use of a common surgical margin reporting system that is simple, reproducible, and prognostic. PMID:26361463

Prevalence and predictive factors for the detection of carcinoma in cavity margin performed at the time of breast lumpectomy.

PubMed

Tengher-Barna, Iulia; Hequet, Delphine; Reboul-Marty, Jeanne; Frassati-Biaggi, Annonciade; Seince, Nathalie; Rodrigues-Faure, Anabela; Uzan, Michèle; Ziol, Marianne

2009-02-01

Margin resection status is a major risk factor for the development of local recurrence in breast conservation therapy for carcinoma. Tumor bed excision sent as separate orientated cavity margins represents a tool to verify the completeness of the carcinoma resection. We aimed to (1) determine the prevalence of positive cavity margin and its influence on subsequent surgical treatment and (2) identify potential predictive factors for positive cavity margins. From 2003 to 2006, 107 (57 years; 30-88) consecutive patients who underwent a lumpectomy for carcinoma with four orientated cavity margins for carcinoma were selected. Preoperative clinical, radiological and histological data, perioperative macroscopic characteristics and definitive histological analysis results were recorded. Lumpectomy or cavity margins were considered as positive when the distance from carcinoma to the margin was less than or equal to 3 mm. Histological examination of cavity margins showed carcinoma in 38 patients (35%), therefore modifying subsequent surgical therapy in 33 cases. Examination of the cavity margins led (1) to avoiding surgical re-excision in 20 cases (lumpectomy margins were positive and the cavity margins negative), (2) to performing a mastectomy or a re-excision in 13 cases (carcinoma was detected in the cavity margins although the lumpectomy margins were negative or tumor size was superior to 3 cm). Between preoperative and perioperative parameters, US scan and macroscopic size of the tumor were predictive factors for positive cavity margins whereas characteristics of the carcinoma determined on biopsy samples and macroscopic status of the lumpectomy margins were not. Our study confirms that the systematic practice of cavity margin resection avoids surgical re-excision and reduces the likelihood of underestimating the extent of the tumor.

Staged margin-controlled excision (SMEX) for lentigo maligna melanoma in situ.

PubMed

Beveridge, Julie; Taher, Muba; Zhu, Jay; Mahmood, Muhammad N; Salopek, Thomas G

2018-06-24

No consensus exists regarding the best surgical strategy to achieve clear surgical margins while minimizing tissue excision when definitely excising lentigo maligna melanoma in situ (LM). The staged margin controlled excision (SMEX) technique is a modification of the spaghetti technique that allows surgeons to minimize margins and ensure complete excision of LM. Our objectives were twofold: a) to evaluate the effectiveness of SMEX for treatment of LM and b) detail the SMEX technique. A retrospective chart review of adult patients who underwent the SMEX technique for treatment of LM from 2011 to 2016 was conducted. Twenty-four patients were identified with predominantly facial lesions. The mean defect size was 12.1 cm 2 . A mean number of two SMEX procedures, with an average margin of 9 mm, were required to obtain complete excision of the LM. Using SMEX, we achieved 100% clearance of LM over a median follow up period of 18 months, with a range of 1-63 months. SMEX offers a reliable surgical excision method that ensures complete excision of LM in a cosmetically sensitive manner. The recurrence outcomes of SMEX are comparable, if not better, than those of alternative excision techniques in the literature. © 2018 Wiley Periodicals, Inc.

Early Oral Tongue Squamous Cell Carcinoma: Sampling of Margins From Tumor Bed and Worse Local Control.

PubMed

Maxwell, Jessica H; Thompson, Lester D R; Brandwein-Gensler, Margaret S; Weiss, Bernhard G; Canis, Martin; Purgina, Bibianna; Prabhu, Arpan V; Lai, Chi; Shuai, Yongli; Carroll, William R; Morlandt, Anthony; Duvvuri, Umamaheswar; Kim, Seungwon; Johnson, Jonas T; Ferris, Robert L; Seethala, Raja; Chiosea, Simion I

2015-12-01

Positive margins are associated with poor prognosis among patients with oral tongue squamous cell carcinoma (SCC). However, wide variation exists in the margin sampling technique. To determine the effect of the margin sampling technique on local recurrence (LR) in patients with stage I or II oral tongue SCC. A retrospective study was conducted from January 1, 1986, to December 31, 2012, in 5 tertiary care centers following tumor resection and elective neck dissection in 280 patients with pathologic (p)T1-2 pN0 oral tongue SCC. Analysis was conducted from June 1, 2013, to January 20, 2015. In group 1 (n = 119), tumor bed margins were not sampled. In group 2 (n = 61), margins were examined from the glossectomy specimen, found to be positive or suboptimal, and revised with additional tumor bed margins. In group 3 (n = 100), margins were primarily sampled from the tumor bed without preceding examination of the glossectomy specimen. The margin status (both as a binary [positive vs negative] and continuous [distance to the margin in millimeters] variable) and other clinicopathologic parameters were compared across the 3 groups and correlated with LR. Local recurrence. Age, sex, pT stage, lymphovascular or perineural invasion, and adjuvant radiation treatment were similar across the 3 groups. The probability of LR-free survival at 3 years was 0.9 and 0.8 in groups 1 and 3, respectively (P = .03). The frequency of positive glossectomy margins was lowest in group 1 (9 of 117 [7.7%]) compared with groups 2 and 3 (28 of 61 [45.9%] and 23 of 95 [24.2%], respectively) (P < .001). Even after excluding cases with positive margins, the median distance to the closest margin was significantly narrower in group 3 (2 mm) compared with group 1 (3 mm) (P = .008). The status (positive vs negative) of margins obtained from the glossectomy specimen correlated with LR (P = .007), while the status of tumor bed margins did not. The status of the tumor bed margin was 24% sensitive (95

Effect of the plane of surgery achieved on local recurrence in patients with operable rectal cancer: a prospective study using data from the MRC CR07 and NCIC-CTG CO16 randomised clinical trial.

PubMed

Quirke, Phil; Steele, Robert; Monson, John; Grieve, Robert; Khanna, Subhash; Couture, Jean; O'Callaghan, Chris; Myint, Arthur Sun; Bessell, Eric; Thompson, Lindsay C; Parmar, Mahesh; Stephens, Richard J; Sebag-Montefiore, David

2009-03-07

Local recurrence rates in operable rectal cancer are improved by radiotherapy (with or without chemotherapy) and surgical techniques such as total mesorectal excision. However, the contributions of surgery and radiotherapy to outcomes are unclear. We assessed the effect of the involvement of the circumferential resection margin and the plane of surgery achieved. In this prospective study, the plane of surgery achieved and the involvement of the circumferential resection margin were assessed by local pathologists, using a standard pathological protocol in 1156 patients with operable rectal cancer from the CR07 and NCIC-CTG CO16 trial, which compared short-course (5 days) preoperative radiotherapy and selective postoperative chemoradiotherapy, between March, 1998, and August, 2005. All analyses were by intention to treat. This trial is registered, number ISRCTN 28785842. 128 patients (11%) had involvement of the circumferential resection margin, and the plane of surgery achieved was classified as good (mesorectal) in 604 (52%), intermediate (intramesorectal) in 398 (34%), and poor (muscularis propria plane) in 154 (13%). We found that both a negative circumferential resection margin and a superior plane of surgery achieved were associated with low local recurrence rates. Hazard ratio (HR) was 0.32 (95% CI 0.16-0.63, p=0.0011) with 3-year local recurrence rates of 6% (5-8%) and 17% (10-26%) for patients who were negative and positive for circumferential resection margin, respectively. For plane of surgery achieved, HRs for mesorectal and intramesorectal groups compared with the muscularis propria group were 0.32 (0.16-0.64) and 0.48 (0.25-0.93), respectively. At 3 years, the estimated local recurrence rates were 4% (3-6%) for mesorectal, 7% (5-11%) for intramesorectal, and 13% (8-21%) for muscularis propria groups. The benefit of short-course preoperative radiotherapy did not differ in the three plane of surgery groups (p=0.30 for trend). Patients in the short

Breast-conservative surgery followed by radiofrequency ablation of margins decreases the need for a second surgical procedure for close or positive margins.

PubMed

Rubio, Isabel T; Landolfi, Stefania; Molla, Meritxell; Cortes, Javier; Xercavins, Jordi

2014-10-01

Excision of breast cancer followed by radiofrequency ablation (eRFA) is a technique designed to increase negative margins in breast-conservative surgical procedures. The objective of this study is to analyze the impact of eRFA in avoiding a second surgical procedure for close or positive margins after a breast-conservative surgical procedure. From February 2008 to May 2010, 20 patients were included. After lumpectomy, the eRFA was performed in the lumpectomy cavity, and biopsies from each margin from the radial ablated cavity walls were obtained. Biopsy samples were assessed for tumor viability. eRFA was successful in 19 of 20 patients. In all patients, the devitalized tissue extended beyond a 5- to 10-mm radial depth of the biopsy sample. Overall, 6 patients (31%) had margins < 2 mm, 4 of them with < 1 mm margin. All 6 of these patients had no tumor viability according to analysis of biopsy samples stained with 2,3,5-triphenyltetrazolium chloride. At a median follow-up of 46 months, no local recurrence had been found. This study supports the feasibility of eRFA treatment. In our study, the eRFA method has spared 31% of patients from undergoing a re-excision surgical procedure, and it may, in the long-term, reduce local recurrences. Copyright © 2014 Elsevier Inc. All rights reserved.

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. Copyright © 2012 Elsevier Ltd. All rights reserved.

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. © 2014 The British Psychological Society.

Early graft dysfunction and mortality rate in marginal donor liver transplantation.

PubMed

Sarkut, Pmar; Gülcü, Bariş; Işçimen, Remzi; Kiyici, Murat; Türker, Gürkan; Topal, Naile Bolca; Ozen, Yilmaz; Kaya, Ekrem

2014-01-01

To determine the effect of marginal donor livers on mortality and graft survival in liver transplantation (LT) recipients. Donors with any 1 of following were considered marginal donors: age ≥65 years, sodium level ≥ 165 mmol/L and cold ischemia time ≥ 12 h. Donors were classified according to the donor risk index (DRI) < 1.7 and ≥ 1.7. The transplant recipients' model for end-stage liver disease (MELD) scores were considered low if < 20 and high if ≥ 20. Early graft dysfunction (EGD) and mortality rate were evaluated. During the study period 47 patients underwent cadaveric LT. The mean age of the donors and recipients was 45 years (range: 5-72 years) and 46 years (range: 4-66 years), respectively. In all, there were 15 marginal donors and 18 donors with a DRI > 1.7. In total, 4 LT patients that received livers from marginal donors and 5 that received livers from donors with a DRI ≥ 1.7 had EGD. Among the recipients of marginal livers, 5 died, versus 4 of the recipients of standard livers. There was no significant difference in EGD or mortality rate between the patients that received livers from marginal donors or those with a DRI ≥ 1.7 and patients that received standard donor livers. Marginal and DRI ≥ 1.7 donors negatively affected LT outcomes, but not significantly.

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

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).

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

Early Oral Tongue Squamous Cell Carcinoma Sampling of Margins From Tumor Bed and Worse Local Control

PubMed Central

Maxwell, Jessica H.; Thompson, Lester D. R.; Brandwein-Gensler, Margaret S.; Weiss, Bernhard G.; Canis, Martin; Purgina, Bibianna; Prabhu, Arpan V.; Lai, Chi; Shuai, Yongli; Carroll, William R.; Morlandt, Anthony; Duvvuri, Umamaheswar; Kim, Seungwon; Johnson, Jonas T.; Ferris, Robert L.; Seethala, Raja; Chiosea, Simion I.

2017-01-01

IMPORTANCE Positive margins are associated with poor prognosis among patients with oral tongue squamous cell carcinoma (SCC). However, wide variation exists in the margin sampling technique. OBJECTIVE To determine the effect of the margin sampling technique on local recurrence (LR) in patients with stage I or II oral tongue SCC. DESIGN, SETTING, AND PARTICIPANTS A retrospective study was conducted from January 1, 1986, to December 31, 2012, in 5 tertiary care centers following tumor resection and elective neck dissection in 280 patients with pathologic (p)T1-2 pN0 oral tongue SCC. Analysis was conducted from June 1, 2013, to January 20, 2015. INTERVENTIONS In group 1 (n = 119), tumor bed margins were not sampled. In group 2 (n = 61), margins were examined from the glossectomy specimen, found to be positive or suboptimal, and revised with additional tumor bed margins. In group 3 (n = 100), margins were primarily sampled from the tumor bed without preceding examination of the glossectomy specimen. The margin status (both as a binary [positive vs negative] and continuous [distance to the margin in millimeters] variable) and other clinicopathologic parameters were compared across the 3 groups and correlated with LR. MAIN OUTCOMES AND MEASURES Local recurrence. RESULTS Age, sex, pT stage, lymphovascular or perineural invasion, and adjuvant radiation treatment were similar across the 3 groups. The probability of LR-free survival at 3 years was 0.9 and 0.8 in groups 1 and 3, respectively (P = .03). The frequency of positive glossectomy margins was lowest in group 1 (9 of 117 [7.7%]) compared with groups 2 and 3 (28 of 61 [45.9%] and 23 of 95 [24.2%], respectively) (P < .001). Even after excluding cases with positive margins, the median distance to the closest margin was significantly narrower in group 3 (2 mm) compared with group 1 (3 mm) (P = .008). The status (positive vs negative) of margins obtained from the glossectomy specimen correlated with LR (P = .007), while

Significance of lobular intraepithelial neoplasia at margins of breast conservation specimens: a report of 38 cases and literature review

PubMed Central

2010-01-01

Background Presence of lobular intraepithelial neoplasia (LIN) is not routinely reported as part of margin assessment in breast conservation therapy (BCT) as in ductal carcinoma in situ (DCIS). With new emerging evidence of LIN as possible precursor lesion, the hypothesis is that LIN at the margin may increase the risk of local recurrence with BCT. The aim is to determine whether there is an increase incidence of recurrence when LIN is found at surgical margins on BCT. Methods We retrospectively reviewed a total of 1,334 BCT at a single institution in a 10 year period. Inclusion criteria are positive margin with LIN from primary BCT containing invasive and/or in situ carcinoma with comparison to the negative control group who had similar diseases with negative margin for LIN. Results We identified 38 cases (2.8%) with LIN either lobular carcinoma in situ/atypical lobular hyperplasia (LCIS/ALH) at a margin on initial BCT with 36% recurrence rate. Of the 38 cases: 5 (13%) were lost to follow-up, 12 (32%) had no further procedures performed and 21 (55%) had re-excision. Out of 21 patients who had re-excisions, 12 (57%) had residual invasive carcinoma or DCIS, three (14%) had pleomorphic LCIS and 4 (19%) showed residual classic type LCIS. 71% had significant residual disease (local recurrence) and 29% had no residual disease. A negative control group consisted of 38 cases. We found two patients with bone or brain metastasis and one local recurrence. Clinical follow up periods range from 1 to 109 months. Conclusions LIN found at a margin on BCT showed a significant recurrent ipsilateral disease. Our study supports the view that LIN seen at the margin may play a role in recurrence. PMID:20727142

PTV margin determination in conformal SRT of intracranial lesions

PubMed Central

Parker, Brent C.; Shiu, Almon S.; Maor, Moshe H.; Lang, Frederick F.; Liu, H. Helen; White, R. Allen; Antolak, John A.

2002-01-01

The planning target volume (PTV) includes the clinical target volume (CTV) to be irradiated and a margin to account for uncertainties in the treatment process. Uncertainties in miniature multileaf collimator (mMLC) leaf positioning, CT scanner spatial localization, CT‐MRI image fusion spatial localization, and Gill‐Thomas‐Cosman (GTC) relocatable head frame repositioning were quantified for the purpose of determining a minimum PTV margin that still delivers a satisfactory CTV dose. The measured uncertainties were then incorporated into a simple Monte Carlo calculation for evaluation of various margin and fraction combinations. Satisfactory CTV dosimetric criteria were selected to be a minimum CTV dose of 95% of the PTV dose and at least 95% of the CTV receiving 100% of the PTV dose. The measured uncertainties were assumed to be Gaussian distributions. Systematic errors were added linearly and random errors were added in quadrature assuming no correlation to arrive at the total combined error. The Monte Carlo simulation written for this work examined the distribution of cumulative dose volume histograms for a large patient population using various margin and fraction combinations to determine the smallest margin required to meet the established criteria. The program examined 5 and 30 fraction treatments, since those are the only fractionation schemes currently used at our institution. The fractionation schemes were evaluated using no margin, a margin of just the systematic component of the total uncertainty, and a margin of the systematic component plus one standard deviation of the total uncertainty. It was concluded that (i) a margin of the systematic error plus one standard deviation of the total uncertainty is the smallest PTV margin necessary to achieve the established CTV dose criteria, and (ii) it is necessary to determine the uncertainties introduced by the specific equipment and procedures used at each institution since the uncertainties may vary

Prospective Analysis of Surgical Bone Margins After Partial Foot Amputation in Diabetic Patients Admitted With Moderate to Severe Foot Infections.

PubMed

Schmidt, Brian M; McHugh, Jonathan B; Patel, Rajiv M; Wrobel, James S

2018-04-01

Osteomyelitis is common in diabetic foot infections and medical management can lead to poor outcomes. Surgical management involves sending histopathologic and microbiologic specimens which guides future intervention. We examined the effect of obtainment of surgical margins in patients undergoing forefoot amputations to identify patient characteristics associated with outcomes. Secondary aims included evaluating interobserver reliability of histopathologic data at both the distal-to and proximal-to surgical bone margin. Data were prospectively collected on 72 individuals and was pooled for analysis. Standardized method to retrieve intraoperative bone margins was established. A univariate analysis was performed. Negative outcomes, including major lower extremity amputation, wound dehiscence, reulceration, reamputation, or death were recorded. Viable proximal margins were obtained in 63 out of 72 cases (87.5%). Strong interobserver reliability of histopathology was recorded. Univariate analysis demonstrated preoperative platelets, albumin, probe-to-bone testing, absolute toe pressures, smaller wound surface area were associated with obtaining viable margins. Residual osteomyelitis resulted in readmission 2.6 times more often and more postoperative complications. Certain patients were significantly different in the viable margin group versus dirty margin group. High interobserver reliability was demonstrated. Obtainment of viable margins resulted in reduced rates of readmission and negative outcomes. Prognostic, Level I: Prospective.

Adapter molecule Grb2-associated binder 1 is specifically expressed in marginal zone B cells and negatively regulates thymus-independent antigen-2 responses.

PubMed

Itoh, Shousaku; Itoh, Motoyuki; Nishida, Keigo; Yamasaki, Satoru; Yoshida, Yuichi; Narimatsu, Masahiro; Park, Sung Joo; Hibi, Masahiko; Ishihara, Katsuhiko; Hirano, Toshio

2002-05-15

Grb2-associated binder 1 (Gab1) is a member of the Gab/daughter of sevenless family of adapter molecules involved in the signal transduction pathways of a variety of growth factors, cytokines, and Ag receptors. To know the role for Gab1 in hematopoiesis and immune responses in vivo, we analyzed radiation chimeras reconstituted with fetal liver (FL) cells of Gab1(-/-) mice, because Gab1(-/-) mice are lethal to embryos. Transfer of Gab1(-/-) FL cells of 14.5 days post-coitum rescued lethally irradiated mice, indicating that Gab1 is not essential for hematopoiesis. Although mature T and B cell subsets developed normally in the peripheral lymphoid organs, reduction of pre-B cells and increase of myeloid cells in the Gab1(-/-) FL chimeras suggested the regulatory roles for Gab1 in hematopoiesis. The chimera showed augmented IgM and IgG1 production to thymus-independent (TI)-2 Ag, although they showed normal responses for thymus-dependent and TI-1 Ags, indicating its negative role specific to TI-2 response. Gab1(-/-) splenic B cells stimulated with anti-delta-dextran plus IL-4 plus IL-5 showed augmented IgM and IgG1 production in vitro that was corrected by the retrovirus-mediated transfection of the wild-type Gab1 gene, clearly demonstrating the cell-autonomous, negative role of Gab1. Furthermore, we showed that the negative role of Gab1 required its Src homology 2-containing tyrosine phosphatase-2 binding sites. Cell fractionation analysis revealed that nonfollicular B cells were responsible for the augmented Ab production in vitro. Consistent with these results, the Gab1 gene was expressed in marginal zone B cells but not follicular B cells. These results indicated that Gab1 is a unique negative regulator specific for TI-2 responses.

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,…

Marginalized Student Access to Technology Education

NASA Astrophysics Data System (ADS)

Kurtcu, Wanda M.

The purpose of this paper is to investigate how a teacher can disrupt an established curriculum that continues the cycle of inequity of access to science, technology, engineering, and math (STEM) curriculum by students in alternative education. For this paper, I will focus on the technology components of the STEM curriculum. Technology in the United States, if not the world economy, is developing at a rapid pace. Many areas of day to day living, from applying for a job to checking one's bank account online, involve a component of science and technology. The 'gap' in technology education is emphasized between the 'haves and have-nots', which is delineated along socio-economic lines. Marginalized students in alternative education programs use this equipment for little else than remedial programs and credit recovery. This level of inequity further widens in alternative education programs and affects the achievement of marginalized students in credit recovery or alternative education classes instead of participation technology classes. For the purposes of this paper I focus on how can I decrease the inequity of student access to 21st century technology education in an alternative education program by addressing the established curriculum of the program and modifying structural barriers of marginalized student access to a technology focused curriculum.

The marginal fit of lithium disilicate crowns: Press vs. CAD/CAM.

PubMed

Azar, Basel; Eckert, Steve; Kunkela, Josef; Ingr, Tomaš; Mounajjed, Radek

2018-01-01

This study aimed to compare the vertical marginal gap of teeth restored with lithium disilicate crowns fabricated using CAD/CAM or by pressed ceramic approach. Twenty mandibular third molar teeth were collected after surgical extractions and prepared to receive full veneer crowns. Teeth were optically scanned and lithium disilicate blocks were used to fabricate crowns using CAD/CAM technique. Polyvinyl siloxane impressions of the prepared teeth were made and monolithic pressed lithium disilicate crowns were fabricated. The marginal gap was measured using optical microscope at 200× magnification (Keyence VHX-5000, Japan). Statistical analysis was performed using Wilcoxon test. The lithium disilicate pressed crowns had significantly smaller (p = 0.006) marginal gaps (38 ± 12 μm) than the lithium disilicate CAD/CAM crowns (45 ± 12 μm). This research indicates that lithium disilicate crowns fabricated with the press technique have measurably smaller marginal gaps compared with those fabricated with CAD/CAM technique within in vitro environments. The marginal gaps achieved by the crowns across all groups were within a clinically acceptable range.

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

PubMed Central

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

2015-01-01

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

Computer-aided marginal artery detection on computed tomographic colonography

NASA Astrophysics Data System (ADS)

Wei, Zhuoshi; Yao, Jianhua; Wang, Shijun; Liu, Jiamin; Summers, Ronald M.

2012-03-01

Computed tomographic colonography (CTC) is a minimally invasive technique for colonic polyps and cancer screening. The marginal artery of the colon, also known as the marginal artery of Drummond, is the blood vessel that connects the inferior mesenteric artery with the superior mesenteric artery. The marginal artery runs parallel to the colon for its entire length, providing the blood supply to the colon. Detecting the marginal artery may benefit computer-aided detection (CAD) of colonic polyp. It can be used to identify teniae coli based on their anatomic spatial relationship. It can also serve as an alternative marker for colon localization, in case of colon collapse and inability to directly compute the endoluminal centerline. This paper proposes an automatic method for marginal artery detection on CTC. To the best of our knowledge, this is the first work presented for this purpose. Our method includes two stages. The first stage extracts the blood vessels in the abdominal region. The eigenvalue of Hessian matrix is used to detect line-like structures in the images. The second stage is to reduce the false positives in the first step. We used two different masks to exclude the false positive vessel regions. One is a dilated colon mask which is obtained by colon segmentation. The other is an eroded visceral fat mask which is obtained by fat segmentation in the abdominal region. We tested our method on a CTC dataset with 6 cases. Using ratio-of-overlap with manual labeling of the marginal artery as the standard-of-reference, our method yielded true positive, false positive and false negative fractions of 89%, 33%, 11%, respectively.

Overactive bladder is a negative predictor of achieving continence after robot-assisted radical prostatectomy.

PubMed

Yamada, Yuta; Fujimura, Tetsuya; Fukuhara, Hiroshi; Sugihara, Toru; Miyazaki, Hideyo; Nakagawa, Tohru; Kume, Haruki; Igawa, Yasuhiko; Homma, Yukio

2017-10-01

To investigate predictors of continence outcomes after robot-assisted radical prostatectomy. Clinical records of 272 patients who underwent robot-assisted radical prostatectomy were investigated. Preoperative Overactive Bladder Symptom Score, International Prostate Symptom Score and clinicopathological factors were investigated, and relationships between factors and recovery of continence after robot-assisted radical prostatectomy were assessed. The presence of overactive bladder was defined as having urgency for more than once a week and having ≥3 points according to the Overactive Bladder Symptom Score. Age (≤66 years) was significantly associated with continence within 6 months after robot-assisted radical prostatectomy (P = 0.033). The absence of overactive bladder and lower Overactive Bladder Symptom Score (<3) were significantly associated with recovery of continence within 12 months after surgery (both variables P = 0.009). In terms of achieving recovery of continence after robot-assisted radical prostatectomy, Kaplan-Meier curves showed earlier recovery in "age ≤66 years," "prostate weight ≤40 g" and "overactive bladder symptom score <3" (P = 0.0072, 0.0172 and 0.0140, respectively). Multivariate analysis showed that the presence of overactive bladder was an independent negative predictor for recovery of continence within 12 months after surgery (P = 0.019). The presence of baseline overactive bladder seems to represent an independent negative predictor for recovery of continence at 12 months after robot-assisted radical prostatectomy. © 2017 The Japanese Urological Association.

Normal flora of conjunctiva and lid margin, as well as its antibiotic sensitivity, in patients undergoing cataract surgery at Phramongkutklao Hospital.

PubMed

Ratnumnoi, Ravee; Keorochana, Narumon; Sontisombat, Chavalit

2017-01-01

This study aimed to evaluate the normal flora of conjunctiva and lid margin, as well as its antibiotic sensitivity. This was a prospective cross-sectional study. A prospective study was conducted on 120 patients who underwent cataract surgery at the Phramongkutklao Hospital from September 2014 to October 2014. Conjunctival and lid margin swabs were obtained from patients before they underwent cataract surgery. These swabs were used to inoculate blood agar and chocolate agar plates for culturing. After growth of the normal flora, the antibiotic sensitivity method using tobramycin, moxifloxacin, levofloxacin, and cefazolin was applied. Normal flora of conjunctiva and lid margin, along with its antibiotic sensitivity, from patients who underwent cataract surgery was assessed. A total of 120 eyes were included in this study, and bacterial isolation rates were identified. Five bacteria from the lid margin were cultured, namely, coagulase-negative staphylococcus (58.33%), Streptococcus spp. (2.5%), Corynebacterium (1.67%), Micrococcus spp. (1.67%), and Staphylococcus aureus (0.83%). Two bacteria from the conjunctiva were cultured, namely, coagulase-negative staphylococcus (30%) and Streptococcus spp. (0.83%). Results of antibiotic sensitivity test showed that all isolated bacteria are sensitive to cefazolin 100%, tobramycin 98.67%, levofloxacin 100%, and moxifloxacin 100%. Coagulase-negative staphylococci are the most common bacteria isolated from conjunctiva and lid margin.

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…

Impact of organ shape variations on margin concepts for cervix cancer ART.

PubMed

Seppenwoolde, Yvette; Stock, Markus; Buschmann, Martin; Georg, Dietmar; Bauer-Novotny, Kwei-Yuang; Pötter, Richard; Georg, Petra

2016-09-01

Target and organ movement motivate adaptive radiotherapy for cervix cancer patients. We investigated the dosimetric impact of margin concepts with different levels of complexity on both organ at risk (OAR) sparing and PTV coverage. Weekly CT and daily CBCT scans were delineated for 10 patients. The dosimetric impact of organ shape variations were evaluated for four (isotropic) margin concepts: two static PTVs (PTV 6mm and PTV 15mm ), a PTV based on ITV of the planning CT and CBCTs of the first treatment week (PTV ART ITV ) and an adaptive PTV based on a library approach (PTV ART Library ). Using static concepts, OAR doses increased with large margins, while smaller margins compromised target coverage. ART PTVs resulted in comparable target coverage and better sparing of bladder (V40Gy: 15% and 7% less), rectum (V40Gy: 18 and 6cc less) and bowel (V40Gy: 106 and 15cc less) compared to PTV 15mm . Target coverage evaluation showed that for elective fields a static 5mm margin sufficed. PTV ART Library achieved the best dosimetric results. However when weighing clinical benefit against workload, ITV margins based on repetitive movement evaluation during the first week also provide improvements over static margin concepts. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

NRC Continental Margins Workshop

NASA Astrophysics Data System (ADS)

Katsouros, Mary Hope

The Ocean Studies Board of the National Research Council is organizing a workshop, “Continental Margins: Evolution of Passive Continental Margins and Active Marginal Processes,” to stimulate discussion and longterm planning in the scientific community about the evolution of all types of continental margins. We want to coordinate academic, industry, and government agency efforts in this field, and to enhance communication between sea-based and land-based research programs.The continental margins constitute the only available record of the long-term dynamic interaction of oceanic and continental lithosphere. Of great interest are the unique structures and thick sedimentary sequences associated with this interaction. A major focus of the workshop will be to define strategies for exploring and understanding the continental margins in three dimensions and through geologic time. The workshop will be divided into 7 working groups, each concentrating on a major issue in continental margins research. A background document is being prepared summarizing recent research in specific continental margin fields and identifying key scientific and technical issues.

Marginality, Credibility, and Impression Management: The Asian Sociologist in America.

ERIC Educational Resources Information Center

Unnithan, N. Prabha

1988-01-01

Relates personal experiences of a sociologist of Asian origin in an effort to illustrate problems inherent in the process of becoming accepted as an academic sociologist. Identifies important themes of marginality, credibility, and impression management. Points out ways in which the Asian sociologists can go about achieving credibility. (KO)

On the existence of black holes in distorted Schwarzschild spacetime using marginally trapped surfaces

NASA Astrophysics Data System (ADS)

Pilkington, Terry

The classical definition of a black hole in terms of an event horizon relies on global properties of the spacetime. Realistic black holes have matter distributions surrounding them, which negates the asymptotic flatness needed for an event horizon. Using the (quasi-)local concept of marginally trapped surfaces, we investigate the Schwarzschild spacetime distorted by an axisymmetric matter distribution. We determine that it is possible to locate a future outer trapping horizon for a given foliation within certain value ranges of multipole moments. Furthermore, we show that there are no marginally trapped surfaces for arbitrary values of the multipole moment magnitudes. KEYWORDS: SCHWARZSCHILD; BLACK HOLE; DISTORTED SPACETIME; MARGINALLY TRAPPED SURFACE; FUTURE OUTER TRAPPING HORIZON

Staged marginal contoured and central excision technique in the surgical management of perianal Paget's disease.

PubMed

Möller, Mecker G; Lugo-Baruqui, Jose Alejandro; Milikowski, Clara; Salgado, Christopher J

2014-04-01

Extramammary Paget's disease (EMPD) is an adenocarcinoma of the apocrine glands with unknown exact prevalence and obscure etiology. It has been divided into primary EMPD and secondary EMPD, in which an internal malignancy is usually associated. Treatment for primary EMPD usually consists of wide lesion excision with negative margins. Multiple methods have been proposed to obtain free-margin status of the disease. These include visible border lesion excision, punch biopsies, and micrographic and frozen-section surgery, with different results but still high recurrence rates. The investigators propose a method consisting of a staged contoured marginal excision using "en face" permanent pathologic analysis preceding the steps of central excision of the lesion and the final reconstruction of the surgical defect. Advantages of this method include adequate margin control allowing final reconstruction and tissue preservation, while minimizing patient discomfort. The staged contoured marginal and central excision technique offers a new alternative to the armamentarium for surgical oncologists for the management of EMPD in which margin control is imperative for control of recurrence rates. Copyright © 2014 Elsevier Inc. All rights reserved.

Diagnosing clean margins through Raman spectroscopy in human and animal mammary tumour surgery: a short review

PubMed Central

Birtoiu, I. A.; Rizea, C.; Togoe, D.; Munteanu, R. M.; Micsa, C.; Rusu, M. I.; Tautan, M.; Braic, L.; Scoicaru, L. O.; Parau, A.; Becherescu-Barbu, N. D.; Udrea, M. V.; Tonetto, A.; Notonier, R.

2016-01-01

Breast cancer frequency in human and other mammal female populations has worryingly increased lately. The acute necessity for taxonomy of the aetiological factors along with seeking for new diagnostic tools and therapy procedures aimed at reducing mortality have yielded in an intense research effort worldwide. Surgery is a regular method to counteract extensive development of breast cancer and prevent metastases provided that negative surgical margins are achieved. This highly technical challenge requires fast, extremely sensitive and selective discrimination between malignant and benign tissues even down to molecular level. The particular advantages of Raman spectroscopy, such as high chemical specificity, and the ability to measure raw samples and optical responses in the visible or near-infrared spectral range, have recently recommended it as a means with elevated potential in precise diagnostic in oncology surgery. This review spans mainly the latter 10 years of exceptional efforts of scientists implementing Raman spectroscopy as a nearly real-time diagnostic tool for clean margins assessment in mastectomy and lumpectomy. Although greatly contributing to medical discoveries for the wealth of humanity, animals as patients have benefitted less from advances in surgery diagnostic using Raman spectroscopy. This work also dedicates a few lines to applications of surface enhanced Raman spectroscopy in veterinary oncological surgery. PMID:27920899

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.

Revealing nonclassicality beyond Gaussian states via a single marginal distribution.

PubMed

Park, Jiyong; Lu, Yao; Lee, Jaehak; Shen, Yangchao; Zhang, Kuan; Zhang, Shuaining; Zubairy, Muhammad Suhail; Kim, Kihwan; Nha, Hyunchul

2017-01-31

A standard method to obtain information on a quantum state is to measure marginal distributions along many different axes in phase space, which forms a basis of quantum-state tomography. We theoretically propose and experimentally demonstrate a general framework to manifest nonclassicality by observing a single marginal distribution only, which provides a unique insight into nonclassicality and a practical applicability to various quantum systems. Our approach maps the 1D marginal distribution into a factorized 2D distribution by multiplying the measured distribution or the vacuum-state distribution along an orthogonal axis. The resulting fictitious Wigner function becomes unphysical only for a nonclassical state; thus the negativity of the corresponding density operator provides evidence of nonclassicality. Furthermore, the negativity measured this way yields a lower bound for entanglement potential-a measure of entanglement generated using a nonclassical state with a beam-splitter setting that is a prototypical model to produce continuous-variable (CV) entangled states. Our approach detects both Gaussian and non-Gaussian nonclassical states in a reliable and efficient manner. Remarkably, it works regardless of measurement axis for all non-Gaussian states in finite-dimensional Fock space of any size, also extending to infinite-dimensional states of experimental relevance for CV quantum informatics. We experimentally illustrate the power of our criterion for motional states of a trapped ion, confirming their nonclassicality in a measurement-axis-independent manner. We also address an extension of our approach combined with phase-shift operations, which leads to a stronger test of nonclassicality, that is, detection of genuine non-Gaussianity under a CV measurement.

Revealing nonclassicality beyond Gaussian states via a single marginal distribution

PubMed Central

Park, Jiyong; Lu, Yao; Lee, Jaehak; Shen, Yangchao; Zhang, Kuan; Zhang, Shuaining; Zubairy, Muhammad Suhail; Kim, Kihwan; Nha, Hyunchul

2017-01-01

A standard method to obtain information on a quantum state is to measure marginal distributions along many different axes in phase space, which forms a basis of quantum-state tomography. We theoretically propose and experimentally demonstrate a general framework to manifest nonclassicality by observing a single marginal distribution only, which provides a unique insight into nonclassicality and a practical applicability to various quantum systems. Our approach maps the 1D marginal distribution into a factorized 2D distribution by multiplying the measured distribution or the vacuum-state distribution along an orthogonal axis. The resulting fictitious Wigner function becomes unphysical only for a nonclassical state; thus the negativity of the corresponding density operator provides evidence of nonclassicality. Furthermore, the negativity measured this way yields a lower bound for entanglement potential—a measure of entanglement generated using a nonclassical state with a beam-splitter setting that is a prototypical model to produce continuous-variable (CV) entangled states. Our approach detects both Gaussian and non-Gaussian nonclassical states in a reliable and efficient manner. Remarkably, it works regardless of measurement axis for all non-Gaussian states in finite-dimensional Fock space of any size, also extending to infinite-dimensional states of experimental relevance for CV quantum informatics. We experimentally illustrate the power of our criterion for motional states of a trapped ion, confirming their nonclassicality in a measurement-axis–independent manner. We also address an extension of our approach combined with phase-shift operations, which leads to a stronger test of nonclassicality, that is, detection of genuine non-Gaussianity under a CV measurement. PMID:28077456

In vitro analysis of the marginal adaptation and discrepancy of stainless steel crowns

PubMed Central

Mulder, Riaan; Medhat, Rasha; Mohamed, Nadia

2018-01-01

Abstract Aim: The purpose of the study was to assess the marginal adaptation and discrepancy of SSC’s. Differences in adaptation and discrepancy between the four surfaces (mesial, lingual, distal, and buccal) were evaluated. Methods: The placement of stainless steel crowns were completed on a phantom head in accordance with the clinical technique. The ideal tooth preparation was made and this ‘master tooth’ duplicated to achieve a sample size of 15. The stainless steel crowns were placed, trimmed, and cemented as per the clinical technique. The cemented stainless crowns were analyzed under 100× stereomicroscope magnification. The marginal adaptation and discrepancy of each specimen was measured every 2 µm. Results: All the specimens showed marginal adaptation and discrepancy. The lingual margin had a significantly better adaptation (p < .0001) over the other surfaces. The buccal surface was the only surface that had an appropriate supra-CEJ level with a significance of p < .0001. Conclusion: The marginal discrepancies occur during the trimming procedure and assessment of the gingival approximation of the SSC margin. The inspection of stainless steel crown adaptation and discrepancy is an essential clinical step. PMID:29536024

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

Marginal adaptation, fracture load and macroscopic failure mode of adhesively luted PMMA-based CAD/CAM inlays.

PubMed

Ender, Andreas; Bienz, Stefan; Mörmann, Werner; Mehl, Albert; Attin, Thomas; Stawarczyk, Bogna

2016-02-01

To evaluate marginal adaptation, fracture load and failure types of CAD/CAM polymeric inlays. Standardized prepared human molars (48) were divided into four groups (n=12): (A) PCG (positive control group); adhesively luted glass-ceramic inlays, (B) TRX; CAD/CAM polymeric inlays luted using a self-adhesive resin cement, (C) TAC; CAD/CAM polymeric inlays luted using a conventional resin cement, and (D) NCG (negative control group); direct-filled resin-based composite restorations. All specimens were subjected to a chewing simulator. Before and after chewing fatigue, marginal adaptation was assessed at two interfaces: (1) between dental hard tissues and luting cement and (2) between luting cement and restoration. Thereafter, the specimens were loaded and the fracture loads, as well as the failure types, were determined. The data were analysed using three- and one-way ANOVA with post hoc Scheffé test, two sample Student's t-test (p<0.05). Before and after chewing fatigue, marginal adaptation for interface 1 showed significantly better results for TRX and PCG than for TAC (p=0.001-0.02) and NCG (p=0.001-0.047). For interface 2, marginal adaptation for TAC was significantly inferior to TRX (p<0.001) and PCG (p<0.001). Chewing fatigue had a negative impact on the marginal adaptation of TAC and NCG. No significant differences in fracture load were found between all tested groups. Self-adhesive luted polymeric CAD/CAM inlays showed similar marginal adaptation and fracture load values compared to adhesively luted glass-ceramic inlays. Copyright © 2015 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

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…

Effect of casting atmosphere on the marginal deficiency and misfit of Ni-Cr alloys with and without beryllium.

PubMed

da Silva, Leandro J; Leal, Monica B; Valente, Mariana L C; de Castro, Denise T; Pagnano, Valéria O; Dos Reis, Andréa C; Bezzon, Osvaldo L

2017-07-01

The marginal adaptation of prosthetic crowns is still a significant clinical problem. The purpose of this in vitro study was to evaluate the marginal deficiency and misfit of Ni-Cr alloys with and without beryllium under different casting conditions. Four casting conditions were selected: flame-torch, induction/argon, induction/vacuum, and induction/air; and 2 alloys were used, Ni-Cr-Be and Ni-Cr. For each group, 10 metal specimens were prepared. Silicone indirect impressions and analysis of the degree of rounding were used to evaluate the marginal deficiencies of metal copings, and a standardized device for the setting pressure associated with optical microscopy was used to analyze the marginal misfit. Results were evaluated with 2-way ANOVA (α=.05), followed by the Tukey honest significant difference post hoc test, and the Pearson correlation test (α=.05). Alloy (P<.001) and casting technique (P<.001) were shown to affect marginal deficiencies. The Ni-Cr cast using the torch technique showed the highest marginal deficiency, and the Ni-Cr-Be cast in a controlled argon atmosphere showed the lowest (P<.001). Alloy (P=.472) and casting techniques (P=.206) did not affect the marginal misfit, but significant differences were found in the interaction (P=.001); the lowest misfit was achieved using the Ni-Cr-Be, and the highest misfit occurred with the molten Ni-Cr, using the cast torch technique. No correlation was found between deficiency and marginal misfit (r=.04, P=.69). The interactions demonstrated that the alloy containing beryllium that was cast in an argon atmosphere led to reduced marginal deficiency. Improved marginal adaptation can be achieved for the same alloy by using the torch technique. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

Automatic Identification & Classification of Surgical Margin Status from Pathology Reports Following Prostate Cancer Surgery

PubMed Central

D’Avolio, Leonard W.; Litwin, Mark S.; Rogers, Selwyn O.; Bui, Alex A. T.

2007-01-01

Prostate cancer removal surgeries that result in tumor found at the surgical margin, otherwise known as a positive surgical margin, have a significantly higher chance of biochemical recurrence and clinical progression. To support clinical outcomes assessment a system was designed to automatically identify, extract, and classify key phrases from pathology reports describing this outcome. Heuristics and boundary detection were used to extract phrases. Phrases were then classified using support vector machines into one of three classes: ‘positive (involved) margins,’ ‘negative (uninvolved) margins,’ and ‘not-applicable or definitive.’ A total of 851 key phrases were extracted from a sample of 782 reports produced between 1996 and 2006 from two major hospitals. Despite differences in reporting style, at least 1 sentence containing a diagnosis was extracted from 780 of the 782 reports (99.74%). Of the 851 sentences extracted, 97.3% contained diagnoses. Overall accuracy of automated classification of extracted sentences into the three categories was 97.18%. PMID:18693818

Risk factors for positive margins in conservative surgery for breast cancer after neoadjuvant chemotherapy.

PubMed

Bouzón, Alberto; Acea, Benigno; García, Alejandra; Iglesias, Ángela; Mosquera, Joaquín; Santiago, Paz; Seoane, Teresa

2016-01-01

Breast conservative surgery after neoadjuvant chemotherapy intends to remove any residual tumor with negative margins. The purpose of this study was to analyze the preoperative clinical-pathological factors influencing the margin status after conservative surgery in breast cancer patients receiving neoadjuvant chemotherapy. A retrospective study of 91 breast cancer patients undergoing neoadjuvant chemotherapy (92 breast lesions) during the period 2006 to 2013. A Cox regression analysis to identify baseline tumor characteristics associated with positive margins after breast conservative surgery was performed. Of all cases, 71 tumors were initially treated with conservative surgery after neoadjuvant chemotherapy. Pathologic exam revealed positive margins in 16 of the 71 cases (22.5%). The incidence of positive margins was significantly higher in cancers with initial size >5cm (P=.021), in cancers with low tumor grade (P=.031), and in patients with hormone receptor-positive cancer (P=.006). After a median follow-up of 45.2 months, 7 patients of the 71 treated with conservative surgery had disease recurrence (9.8%). There was no significant difference in terms of disease-free survival according to the margin status (P=.596). A baseline tumor size >5cm, low tumor grade and hormone receptor-positive status increase the risk for surgical margin involvement in breast conservative surgery after neoadjuvant chemotherapy. Copyright © 2016 AEC. Publicado por Elsevier España, S.L.U. All rights reserved.

Promoting Student Academic Achievement through Faculty Development about Inclusive Teaching

ERIC Educational Resources Information Center

Schmid, Megan E.; Gillian-Daniel, Donald L.; Kraemer, Sara; Kueppers, Mark

2016-01-01

The achievement gap, disparities in the academic achievement of marginalized students (e.g., underrepresented minority, first generation in their family to attend college, and low socio-economic status undergraduate students) relative to their non-minority peers is a pervasive problem in higher education. It impacts student access to the major and…

Limited Margin Radiation Therapy for Children and Young Adults With Ewing Sarcoma Achieves High Rates of Local Tumor Control

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

Talleur, Aimee C.; Navid, Fariba; Spunt, Sheri L.

Purpose: To determine the rate of local failure using focal conformal, limited margin radiation therapy (RT) and dose escalation for tumors ≥8 cm (greatest dimension at diagnosis) in children and young adults with Ewing sarcoma (EWS). Methods and Materials: Eligible patients with EWS were treated on a phase 2 institutional trial of focal conformal, limited margin RT using conformal or intensity modulated techniques. The treatment volume incorporated a 1-cm constrained margin around the gross tumor. Unresected tumors, <8 cm at diagnosis, received a standard dose of 55.8 Gy and tumors ≥8 cm, an escalated dose to 64.8 Gy. Patients with microscopic residual disease after resectionmore » received adjuvant RT to 50.4 Gy. Adjuvant brachytherapy was permitted in selected patients. Results: Forty-five patients were enrolled: 26 with localized and 19 with metastatic disease. Median (range) age, tumor size, and follow-up were 13.0 years (2.9-24.7 years), 9.0 cm (2.4-17.0 cm), and 54.5 months (1.9-122.2 months), respectively. All patients received systemic chemotherapy. The median (range) RT dose for all patients was 56.1 Gy (45-65.5 Gy). Seventeen patients received adjuvant, 16 standard-dose, and 12 escalated-dose RT. Failures included 1 local, 10 distant, and 1 local/distant. The estimated 10-year cumulative incidence of local failure was 4.4% ± 3.1%, with no statistical difference seen between RT treatment groups and no local failures in the escalated-dose RT treatment group. Conclusions: Treatment with focal conformal, limited margin RT, including dose escalation for larger tumors, provides favorable local tumor control in EWS.« less

Metrics help rural hospitals achieve world-class performance.

PubMed

Goodspeed, Scott W

2006-01-01

This article describes the emerging trend of using metrics in rural hospitals to achieve world-class performance. This trend is a response to the fact that rural hospitals have small patient volumes yet must maintain a profit margin in order to fulfill their mission to the community. The conceptual idea for this article is based largely on Robert Kaplan and David Norton's Balanced Scorecard articles in the Harvard Business Review. The ideas also come from the experiences of the 60-plus rural hospitals that are using the Balanced Scorecard and their implementation of metrics to influence performance and behavior. It is indeed possible for rural hospitals to meet and exceed the unique needs of patients and physicians (customers), to achieve healthy profit margins, and to be the rural hospital of choice that employees are proud to work for.

Marginal Matter

NASA Astrophysics Data System (ADS)

van Hecke, Martin

2013-03-01

All around us, things are falling apart. The foam on our cappuccinos appears solid, but gentle stirring irreversibly changes its shape. Skin, a biological fiber network, is firm when you pinch it, but soft under light touch. Sand mimics a solid when we walk on the beach but a liquid when we pour it out of our shoes. Crucially, a marginal point separates the rigid or jammed state from the mechanical vacuum (freely flowing) state - at their marginal points, soft materials are neither solid nor liquid. Here I will show how the marginal point gives birth to a third sector of soft matter physics: intrinsically nonlinear mechanics. I will illustrate this with shock waves in weakly compressed granular media, the nonlinear rheology of foams, and the nonlinear mechanics of weakly connected elastic networks.

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

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

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 plantmore » 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.« less

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

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…

The impact of frozen sections on final surgical margins in squamous cell carcinoma of the oral cavity and lips: a retrospective analysis over an 11 years period

PubMed Central

2011-01-01

Background Taking intraoperative frozen sections (FS) is a widely used procedure in oncologic surgery. However so far no evidence of an association of FS analysis and premalignant changes in the surgical margin exists. Therefore, the aim of this study was to evaluate the impact of FS on different categories of the final margins of squamous cell carcinoma (SCC) of the oral cavity and lips. Methods FS, pT-stage, grading, and tumor localization of 178 patients with SCC of the oral cavity and lips were compared by uni- and multivariate analysis in patients with positive, dysplastic and negative surgical margin status. Results Performed on 111 patients (62.4%), intraoperative FS did not have any statistically significant influence on final margin status, independent of whether it was positive (p = 0.40), dysplastic (p = 0.70), or negative (p = 0.70). Positive surgical margins in permanent sections were significantly associated with pT4-tumors (OR 5.61, p = 0.001). The chance for negative margins in permanent sections was significantly higher in tumors located in the tongue (OR 4.70, p = 0.01). Conclusions Our data suggests that intraoperative FS in SCC can be useful in selected cases. However it is not advisable as a routine approach. PMID:22208692

The Versatile Lid Crease Approach to Upper Eyelid Margin Rotation.

PubMed

Cruz, Antonio A V; Akaishi, Patricia M S; Al-Dufaileej, Mohammed; Galindo-Ferreiro, Alicia

2015-01-01

Lid margin rotational procedures have been used to correct cicatricial trachomatous entropion since the 19(th) century. There are two basic types of surgeries used for lid margin rotation. The first type is based on through-and-through approach combining tarsotomy and the use of sutures on the anterior lamella. The second type of surgery was suggested by Trabut, who proposed a tarsal advancement by posterior approach. We demonstrate that using a lid crease incision combines the basic mechanisms of the anterior and posterior approaches and in addition, addresses a variety of lid problems commonly found in the aged population with cicatricial entropion. After tarsal plate exposure, a tarsotomy through conjunctiva is performed as described by Trabut. Then, instead of using external sutures secured by bolsters, internal absorbable sutures can be used to simultaneously advance the distal tarsal fragment and exert strong tension on the marginal orbicularis muscle. Sixty lids of 40 patients underwent surgery with a lid crease incision. The follow-up ranged from 1 to 12 months (mean 3.0 months ± 2.71). Forty percent of the patients (24 lids) had more than 3 months of follow-up. Adequate margin rotation was achieved in all lids but one that showed a medial eyelash touching the cornea.

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

Trainees do not negatively impact the institutional learning curve for robotic prostatectomy as characterized by operative time, estimated blood loss, and positive surgical margin rate.

PubMed

Schroeck, Florian R; de Sousa, Chiquita A Palha; Kalman, Ross A; Kalia, Maitri S; Pierre, Sean A; Haleblian, George E; Sun, Leon; Moul, Judd W; Albala, David M

2008-04-01

We evaluated the learning curves and perioperative outcomes of an experienced laparoscopic surgeon and his trainees to assess our structured teaching program. We retrieved 383 patients undergoing robot-assisted laparoscopic prostatectomy (RALP) from our database. Trainees completed a structured teaching program and were categorized as early (days 0 to 232), mid (days 566 to 797), and late (days 825 to 1218) according to the time period in which they were working with the mentor. We compared operative times, estimated blood loss (EBL), and positive surgical margin (PSM) rates between the trainees and the mentor (Mann-Whitney and Chi-square test). Association of EBL, body mass index (BMI), and prostate weight with operative time was evaluated in multivariate linear regression analysis. Median operative times of the early, mid, and late trainees (258, 220, and 200 minutes) significantly decreased and were similar to the corresponding senior surgeon's (254, 242, and 180 minutes). Operative times decreased with lower BMI, EBL, and prostate weight (P = 0.006, P <0.001, and P <0.001, respectively). Overall, EBL (150 mL vs. 150 mL, P = 0.215) and PSM rates (20% vs. 18.6%, P = 0.741) did not differ between the mentor and the trainees. A structured teaching program for RALP is effective and trainees are able to adopt the increased efficiency and skills of their mentor. Lower BMI, EBL, and prostate weight were associated with shorter operative times. Trainees performing the procedure did not negatively affect EBL and positive surgical margin rate.

Prospect theory does not describe the feedback-related negativity value function.

PubMed

Sambrook, Thomas D; Roser, Matthew; Goslin, Jeremy

2012-12-01

Humans handle uncertainty poorly. Prospect theory accounts for this with a value function in which possible losses are overweighted compared to possible gains, and the marginal utility of rewards decreases with size. fMRI studies have explored the neural basis of this value function. A separate body of research claims that prediction errors are calculated by midbrain dopamine neurons. We investigated whether the prospect theoretic effects shown in behavioral and fMRI studies were present in midbrain prediction error coding by using the feedback-related negativity, an ERP component believed to reflect midbrain prediction errors. Participants' stated satisfaction with outcomes followed prospect theory but their feedback-related negativity did not, instead showing no effect of marginal utility and greater sensitivity to potential gains than losses. Copyright © 2012 Society for Psychophysiological Research.

Critical Consciousness: A Key to Student Achievement

ERIC Educational Resources Information Center

El-Amin, Aaliyah; Seider, Scott; Graves, Daren; Tamerat, Jalene; Clark, Shelby; Soutter, Madora; Johannsen, Jamie; Malhotra, Saira

2017-01-01

Research has suggested that critical consciousness--the ability to recognize and analyze systems of inequality and the commitment to take action against these systems--can be a gateway to academic motivation and achievement for marginalized students. To explore this approach, the authors studied five urban schools that include critical…

Marginal kidney donor

PubMed Central

Gopalakrishnan, Ganesh; Gourabathini, Siva Prasad

2007-01-01

Renal transplantation is the treatment of choice for a medically eligible patient with end stage renal disease. The number of renal transplants has increased rapidly over the last two decades. However, the demand for organs has increased even more. This disparity between the availability of organs and waitlisted patients for transplants has forced many transplant centers across the world to use marginal kidneys and donors. We performed a Medline search to establish the current status of marginal kidney donors in the world. Transplant programs using marginal deceased renal grafts is well established. The focus is now on efforts to improve their results. Utilization of non-heart-beating donors is still in a plateau phase and comprises a minor percentage of deceased donations. The main concern is primary non-function of the renal graft apart from legal and ethical issues. Transplants with living donors outnumbered cadaveric transplants at many centers in the last decade. There has been an increased use of marginal living kidney donors with some acceptable medical risks. Our primary concern is the safety of the living donor. There is not enough scientific data available to quantify the risks involved for such donation. The definition of marginal living donor is still not clear and there are no uniform recommendations. The decision must be tailored to each donor who in turn should be actively involved at all levels of the decision-making process. In the current circumstances, our responsibility is very crucial in making decisions for either accepting or rejecting a marginal living donor. PMID:19718332

Geology of continental margins

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

Not Available

With continued high interest in offshore petroleum exploration, the 1977 AAPG Short Course presents the latest interpretations of new data bearing on the geology and geophysics of continental margins. Seven well-known earth scientists have organized an integrated program covering major topics involved in the development of ocean basins and continental margins with emphasis on the slopes and rises. The discussion of plate tectonics and evolution of continental margins is followed by presentations on the stratigraphy and structure of pull-apart and compressional margins. Prospective petroleum source rocks, their organic content, rate of burial, and distribution on slopes and rises of differentmore » margin types is covered. Prospective reservoir rock patterns are related to depositional processes and to the sedimentary and structural histories for different types of continental margins. Finally, the seismic recognition of depositional facies on slopes and rises for different margin types with varying rates of sediment supply during eustatic sea-level changes are discussed. The course with this syllabus offers an invaluable opportunity for explorationists to refresh their understanding of the geology associated with an important petroleum frontier. In addition, the course sets forth a technical frame of reference for the case-histoy papers to be presented later in the AAPG Research Symposium on the Petroleum Potential of Slopes, Rises, and Plateaus.« less

Mohs micrographic surgery in dermatofibrosarcoma protuberans allows tumour clearance with smaller margins and greater preservation of healthy tissue compared with conventional surgery: a study of 74 primary cases.

PubMed

Serra-Guillén, C; Llombart, B; Nagore, E; Guillén, C; Requena, C; Traves, V; Kindem, S; Alcalá, R; Rivas, N; Sanmartín, O

2015-01-01

Dermatofibrosarcoma protuberans (DFSP) is an uncommon skin tumour with aggressive local growth. Whether DFSP should be treated with conventional surgery (CS) or Mohs micrographic surgery (MMS) has long been a topic of debate. To calculate, in a large series of DFSP treated by MMS, the minimum margin that would have been needed to achieve complete clearance by CS. Secondly, to calculate the percentage of healthy tissue that was preserved by MMS rather than CS with 2- and 3-cm margins. The minimum margin was calculated by measuring the largest distance from the visible edge of the tumour to the edge of the definitive surgical defect. Tumour and surgical defect areas for hypothetical CS with 2- and 3-cm margins were calculated using AutoCAD for Windows. A mean minimum margin of 1·34 cm was required to achieve complete clearance for the 74 tumours analysed. The mean percentages of skin spared using MMS rather than CS with 2- and 3-cm margins were 49·4% and 67·9%, respectively. MMS can achieve tumour clearance with smaller margins and greater preservation of healthy tissue than CS. © 2014 British Association of Dermatologists.

The marginal fit of E.max Press and E.max CAD lithium disilicate restorations: A critical review.

PubMed

Mounajjed, Radek; M Layton, Danielle; Azar, Basel

2016-12-01

This critical review aimed to assess the vertical marginal gap that was present when E.max lithium disilicate-based restoration (Press and CAD) are fabricated in-vitro. Published articles reporting vertical marginal gap measurements of in-vitro restorations that had been fabricated from E.Max lithium disilicate were sought with an electronic search of MEDLINE (PubMed) and hand search of selected dental journals. The outcomes were reviewed qualitatively. The majority of studies that compared the marginal fit of E.max press and E.max CAD restorations, found that the E.max lithium disilicate restorations fabricated with the press technique had significantly smaller marginal gaps than those fabricated with CAD technique. This research indicates that E.max lithium disilicate restorations fabricated with the press technique have measurably smaller marginal gaps when compared with those fabricated with CAD techniques within in-vitro environments. The marginal gaps achieved by the restorations across all groups were within a clinically acceptable range.

What is the best surgical margin for a Basal cell carcinoma: a meta-analysis of the literature.

PubMed

Gulleth, Yusuf; Goldberg, Nelson; Silverman, Ronald P; Gastman, Brian R

2010-10-01

Current management of basal cell carcinoma is surgical excision. Most resections use predetermined surgical margins. The basis of ideal resection margins is almost completely from retrospective data and mainly from small case series. This article presents a systematic analysis from a large pool of data to provide a better basis of determining ideal surgical margin. A systematic analysis was performed on data from 89 articles from a larger group of 973 articles selected from the PubMed database. Relevant inclusion and exclusion criteria were applied to all articles reviewed and the data were entered into a database for statistical analysis. The total number of lesions analyzed was 16,066; size ranged from 3 to 30 mm (mean, 11.7 ± 5.9 mm). Surgical margins ranged from 1 to 10 mm (mean, 3.9 ± 1.4 mm). Negative surgical margins ranged 45 to 100 percent (mean, 86 ± 12 percent). Recurrence rates for 5-, 4-, 3-, and 2-mm surgical margins were 0.39, 1.62, 2.56, and 3.96 percent, respectively. Pooled data for incompletely excised margins have an average recurrence rate of 27 percent. A 3-mm surgical margin can be safely used for nonmorpheaform basal cell carcinoma to attain 95 percent cure rates for lesions 2 cm or smaller. A positive pathologic margin has an average recurrence rate of 27 percent.

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.

Indigenous women's voices: marginalization and health.

PubMed

Dodgson, Joan E; Struthers, Roxanne

2005-10-01

Marginalization may affect health care delivery. Ways in which indigenous women experienced marginalization were examined. Data from 57 indigenous women (18 to 65 years) were analyzed for themes. Three themes emerged: historical trauma as lived marginalization, biculturalism experienced as marginalization, and interacting within a complex health care system. Experienced marginalization reflected participants' unique perspective and were congruent with previous research. It is necessary for health care providers to assess the detrimental impact of marginalization on the health status of individuals and/or communities.

Relationships between negative affect and academic achievement among secondary school students: the mediating effects of habituated exercise.

PubMed

Hashim, Hairul A; Freddy, Golok; Rosmatunisah, Ali

2012-09-01

The current study was undertaken to examine the associations between self-determination, exercise habit, anxiety, depression, stress, and academic achievement among adolescents aged 13 and 14 years in eastern Malaysia. The sample consisted of 750 secondary school students (mean age = 13.4 years, SD = 0.49). Participants completed self-report measures of exercise behavioral regulation, negative affect, and exercise habit strength. Midyear exam results were used as an indicator of academic performance. Structural equation modeling was used to analyze the data. The results of structural equation modeling revealed a close model fit for the hypothesized model, which indicates that higher levels of self-determination were positively associated with habituated exercise behavior. In turn, exercise habit strength fostered academic achievement and buffered the debilitative effect of stress, depression, and anxiety on student academic performance. The analysis of model invariance revealed a nonsignificant difference between male and female subjects. The findings support the notion that habituated exercise fosters academic performance. In addition, we found that habituated exercise buffers the combined effects of stress, anxiety and depression on academic performance. The finding also supports the roles of self-determination in promoting exercise habituation.

Margin-maximizing feature elimination methods for linear and nonlinear kernel-based discriminant functions.

PubMed

Aksu, Yaman; Miller, David J; Kesidis, George; Yang, Qing X

2010-05-01

Feature selection for classification in high-dimensional spaces can improve generalization, reduce classifier complexity, and identify important, discriminating feature "markers." For support vector machine (SVM) classification, a widely used technique is recursive feature elimination (RFE). We demonstrate that RFE is not consistent with margin maximization, central to the SVM learning approach. We thus propose explicit margin-based feature elimination (MFE) for SVMs and demonstrate both improved margin and improved generalization, compared with RFE. Moreover, for the case of a nonlinear kernel, we show that RFE assumes that the squared weight vector 2-norm is strictly decreasing as features are eliminated. We demonstrate this is not true for the Gaussian kernel and, consequently, RFE may give poor results in this case. MFE for nonlinear kernels gives better margin and generalization. We also present an extension which achieves further margin gains, by optimizing only two degrees of freedom--the hyperplane's intercept and its squared 2-norm--with the weight vector orientation fixed. We finally introduce an extension that allows margin slackness. We compare against several alternatives, including RFE and a linear programming method that embeds feature selection within the classifier design. On high-dimensional gene microarray data sets, University of California at Irvine (UCI) repository data sets, and Alzheimer's disease brain image data, MFE methods give promising results.

Early Childhood Lead Exposure and Academic Achievement: Evidence From Detroit Public Schools, 2008–2010

PubMed Central

Baker, Harolyn W.; Tufts, Margaret; Raymond, Randall E.; Salihu, Hamisu; Elliott, Michael R.

2013-01-01

Objectives. We assessed the long-term effect of early childhood lead exposure on academic achievement in mathematics, science, and reading among elementary and junior high school children. Methods. We linked early childhood blood lead testing surveillance data from the Detroit Department of Health and Wellness Promotion to educational testing data from the Detroit, Michigan, public schools. We used the linked data to investigate the effect of early childhood lead exposure on academic achievement among school-aged children, both marginally and adjusted for grade level, gender, race, language, maternal education, and socioeconomic status. Results. High blood lead levels before age 6 years were strongly associated with poor academic achievement in grades 3, 5, and 8. The odds of scoring less than proficient for those whose blood lead levels were greater than 10 micrograms per deciliter were more than twice the odds for those whose blood lead levels were less than 1 micrograms per deciliter after adjustment for potential confounders. Conclusions. Early childhood lead exposure was negatively associated with academic achievement in elementary and junior high school, after adjusting for key potential confounders. The control of lead poisoning should focus on primary prevention of lead exposure in children and development of special education programs for students with lead poisoning. PMID:23327265

Margin Status Remains an Important Determinant of Survival after Surgical Resection of Colorectal Liver Metastases in the Era of Modern Chemotherapy

PubMed Central

Andreou, Andreas; Aloia, Thomas A.; Brouquet, Antoine; Dickson, Paxton V.; Zimmitti, Giuseppe; Maru, Dipen M.; Kopetz, Scott; Loyer, Evelyne M.; Curley, Steven A.; Abdalla, Eddie K.; Vauthey, Jean-Nicolas

2013-01-01

Objective To determine the impact of surgical margin status on overall survival (OS) of patients undergoing hepatectomy for colorectal liver metastases (CLM) after modern preoperative chemotherapy. Summary Background Data In the era of effective chemotherapy for CLM, the association between surgical margin status and survival has become controversial. Methods Clinicopathologic data and outcomes for 378 patients treated with modern preoperative chemotherapy and hepatectomy were analyzed. The effect of positive margins on OS was analyzed in relation to pathologic and computed tomography-based morphologic response to chemotherapy. Results Fifty-two of 378 resections (14%) were R1 resections (tumor-free margin < 1 mm). The 5-year OS rates for patients with R0 resection (margin ≥ 1 mm) and R1 resection were 55% and 26%, respectively (P=0.017). Multivariate analysis identified R1 resection (P=0.03) and minor pathologic response to chemotherapy (P=0.002) as the 2 factors independently associated with worse survival. The survival benefit associated with negative margins (R0 vs. R1 resection) was greater in patients with suboptimal morphologic response (5-year OS rate: 62% vs. 11%, P=0.007) than in patients with optimal response (3-year OS rate: 92% vs. 88%, P=0.917) and greater in patients with minor pathologic response (5-year OS rate: 46% vs. 0%, P=0.002) than in patients with major response (5-year OS rate: 63% vs. 67%, P=0.587). Conclusions In the era of modern chemotherapy, negative margins remain an important determinant of survival and should be the primary goal of surgical therapy. The impact of positive margins is most pronounced in patients with suboptimal response to systemic therapy. PMID:23426338

Margin status remains an important determinant of survival after surgical resection of colorectal liver metastases in the era of modern chemotherapy.

PubMed

Andreou, Andreas; Aloia, Thomas A; Brouquet, Antoine; Dickson, Paxton V; Zimmitti, Giuseppe; Maru, Dipen M; Kopetz, Scott; Loyer, Evelyne M; Curley, Steven A; Abdalla, Eddie K; Vauthey, Jean-Nicolas

2013-06-01

To determine the impact of surgical margin status on overall survival (OS) of patients undergoing hepatectomy for colorectal liver metastases after modern preoperative chemotherapy. In the era of effective chemotherapy for colorectal liver metastases, the association between surgical margin status and survival has become controversial. Clinicopathologic data and outcomes for 378 patients treated with modern preoperative chemotherapy and hepatectomy were analyzed. The effect of positive margins on OS was analyzed in relation to pathologic and computed tomography-based morphologic response to chemotherapy. Fifty-two of 378 resections (14%) were R1 resections (tumor-free margin <1 mm). The 5-year OS rates for patients with R0 resection (margin ≥1 mm) and R1 resection were 55% and 26%, respectively (P = 0.017). Multivariate analysis identified R1 resection (P = 0.03) and a minor pathologic response to chemotherapy (P = 0.002) as the 2 factors independently associated with worse survival. The survival benefit associated with negative margins (R0 vs R1 resection) was greater in patients with suboptimal morphologic response (5-year OS rate: 62% vs 11%; P = 0.007) than in patients with optimal response (3-year OS rate: 92% vs 88%; P = 0.917) and greater in patients with a minor pathologic response (5-year OS rate: 46% vs 0%; P = 0.002) than in patients with a major response (5-year OS rate: 63% vs 67%; P = 0.587). In the era of modern chemotherapy, negative margins remain an important determinant of survival and should be the primary goal of surgical therapy. The impact of positive margins is most pronounced in patients with suboptimal response to systemic therapy.

Fluorophore-conjugated antibodies for imaging and resection of GI tumors

NASA Astrophysics Data System (ADS)

Bouvet, Michael; Hoffman, Robert M.

2016-03-01

Negative surgical margins are critical to prevent recurrence in cancer surgery. This is because with current technology in many cases negative margins are impossible due the inability of the surgeon to detect the margin. Our laboratory has developed fluorophore-labeled monoclonal antibodies to aid in cancer visualization in orthotopic nude mouse models of human gastrointestinal (GI) cancer in order to achieve negative margins in fluorescence-guided surgery (FGS). The technologies described herein have the potential to change the paradigm of surgical oncology to engender significantly improved outcomes.

[Organ-limited prostate cancer with positive resection margins. Importance of adjuvant radiation therapy].

PubMed

Porres, D; Pfister, D; Brehmer, B; Heidenreich, A

2012-09-01

For pT3 prostate cancer with positive resection margins, the importance of postoperative radiation therapy is confirmed by a high level of evidence. However, for the pT2,R1 situation prospective, randomized studies concerning this question are lacking. Despite better local tumor control in the pT2 stage the PSA recurrence rate lies between 25% and 40% and positive margins are an independent factor for recurrence. Retrospective studies suggest a positive effect of adjuvant or salvage radiation for the oncological outcome in the pT2,R1 situation. On the other hand the side effects profile, with a potentially negative influence of postoperative continence and various delayed toxicities, is not insignificant despite modern radiation techniques and in the era of ultrasensitive PSA analysis should be considered in the risk-benefit assessment. As long as the optimal initiation of postoperative radiation therapy is unclear, the assessment of indications for adjuvant or salvage radiation for organ-limited prostate cancer with positive resection margins should be made after an individual patient consultation and under consideration of the recurrence risk factors, such as the Gleason grade and the localization and extent of the resection margins.

Frozen Section Evaluation of Margin Status in Primary Squamous Cell Carcinomas of the Head and Neck: A Correlation Study of Frozen Section and Final Diagnoses.

PubMed

Layfield, Eleanor M; Schmidt, Robert L; Esebua, Magda; Layfield, Lester J

2018-06-01

Frozen section is routinely used for intraoperative margin evaluation in carcinomas of the head and neck. We studied a series of frozen sections performed for margin status of head and neck tumors to determine diagnostic accuracy. All frozen sections for margin control of squamous carcinomas of the head and neck were studied from a 66 month period. Frozen and permanent section diagnoses were classified as negative or malignant. Correlation of diagnoses was performed to determine accuracy. One thousand seven hundred and ninety-six pairs of frozen section and corresponding permanent section diagnoses were obtained. Discordances were found in 55 (3.1%) pairs. In 35 pairs (1.9%), frozen section was reported as benign, but permanent sections disclosed carcinoma. In 21 cases, the discrepancy was due to sampling and in the remaining cases it was an interpretive error. In 20 cases (1.1%), frozen section was malignant, but the permanent section was interpreted as negative. Frozen section is an accurate method for evaluation of operative margins for head and neck carcinomas with concordance between frozen and permanent results of 97%. Most errors are false negative results with the majority of these being due to sampling issues.

The importance of familia for Latina/o college students: examining the role of familial support in intragroup marginalization.

PubMed

Llamas, Jasmín D; Morgan Consoli, Melissa

2012-10-01

Intragroup marginalization refers to the perceived interpersonal distancing by members of the heritage culture when an individual exhibits cultural characteristics of the dominant group. This study expands understanding of the college experience of Latina/o students by examining relationships between intragroup marginalization, college adjustment, resilience, and thriving in a sample of 181 Latina/o college students, ranging from freshman to graduate students. In addition, the role of familial social support is explored to determine any possible mediating effects on the relationship between intragroup marginalization, college adjustment, resilience, and thriving. Findings revealed that intragroup marginalization predicted college adjustment, resilience, and thriving. Familial social support was found to mediate the relationship between intragroup marginalization and thriving. This research highlights the negative impact of intragroup marginalization for Latina/o students, as well as the role of familial support in thriving. The results also shed light on the Latina/o college experience as a means to improving Latina/o students' college outcomes. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

Intraoperative narrow band imaging better delineates superficial resection margins during transoral laser microsurgery for early glottic cancer.

PubMed

Garofolo, Sabrina; Piazza, Cesare; Del Bon, Francesca; Mangili, Stefano; Guastini, Luca; Mora, Francesco; Nicolai, Piero; Peretti, Giorgio

2015-04-01

The high rate of positive margins after transoral laser microsurgery (TLM) remains a matter of debate. This study investigates the effect of intraoperative narrow band imaging (NBI) examination on the incidence of positive superficial surgical margins in early glottic cancer treated by TLM. Between January 2012 and October 2013, 82 patients affected by Tis-T1a glottic cancer were treated with TLM by type I or II cordectomies. Intraoperative NBI evaluation was performed using 0-degree and 70-degree rigid telescopes. Surgical specimens were oriented by marking the superior edge with black ink and sent to a dedicated pathologist. Comparison between the rate of positive superficial margins in the present cohort and in a matched historical control group treated in the same way without intraoperative NBI was calculated by chi-square test. At histopathological examination, all surgical margins were negative in 70 patients, whereas 7 had positive deep margins, 2 close, and 3 positive superficial margins. The rate of positive superficial margins was thus 3.6% in the present group and 23.7% in the control cohort (P<.001). Routine use of intraoperative NBI increases the accuracy of neoplastic superficial spreading evaluation during TLM for early glottic cancer. © The Author(s) 2014.

What Happens to the Fish's Achievement in a Little Pond? A Simultaneous Analysis of Class-Average Achievement Effects on Achievement and Academic Self-Concept

ERIC Educational Resources Information Center

Stäbler, Franziska; Dumont, Hanna; Becker, Michael; Baumert, Jürgen

2017-01-01

Empirical studies have demonstrated that students who are taught in a group of students with higher average achievement benefit in terms of their achievement. However, there is also evidence showing that being surrounded by high-achieving students has a negative effect on students' academic self-concept, also known as the big-fish--little-pond…

Anomalous Subsidence at Rifted Continental Margins: Distinguishing Mantle Dynamic Topography from Anomalous Oceanic Crustal Thickness

NASA Astrophysics Data System (ADS)

Cowie, L.; Kusznir, N. J.

2012-12-01

It has been proposed that some continental rifted margins have anomalous subsidence histories and that at breakup they were elevated at shallower bathymetries than the isostatic response of classical rift models (McKenzie 1978) would predict. The existence of anomalous syn or post breakup subsidence of this form would have important implications for our understanding of the geodynamics of continental breakup and rifted continental margin formation, margin subsidence history and the evolution of syn and post breakup depositional systems. We have investigated three rifted continental margins; the Gulf of Aden, Galicia Bank and the Gulf of Lions, to determine whether the oceanic crust in the ocean-continent transition of these margins has present day anomalous subsidence and if so, whether it is caused by mantle dynamic topography or anomalous oceanic crustal thickness. Residual depth anomalies (RDA) corrected for sediment loading, using flexural backstripping and decompaction, have been calculated by comparing observed and age predicted oceanic bathymetries in order to identify anomalous oceanic bathymetry and subsidence at these margins. Age predicted bathymetric anomalies have been calculated using the thermal plate model predictions from Crosby & McKenzie (2009). Non-zero sediment corrected RDAs may result from anomalous oceanic crustal thickness with respect to the global average, or from mantle dynamic uplift. Positive RDAs may result from thicker than average oceanic crust or mantle dynamic uplift; negative RDAs may result from thinner than average oceanic crust or mantle dynamic subsidence. Gravity inversion incorporating a lithosphere thermal gravity anomaly correction and sediment thickness from 2D seismic data has been used to determine Moho depth and oceanic crustal basement thickness. The reference Moho depths used in the gravity inversion have been calibrated against seismic refraction Moho depths. The gravity inversion crustal basement thicknesses

Positive Margins by Oropharyngeal Subsite in Transoral Robotic Surgery for T1/T2 Squamous Cell Carcinoma.

PubMed

Persky, Michael J; Albergotti, William G; Rath, Tanya J; Kubik, Mark W; Abberbock, Shira; Geltzeiler, Mathew; Kim, Seungwon; Duvvuri, Umamaheswar; Ferris, Robert L

2018-04-01

Objective To compare positive margin rates between the 2 most common subsites of oropharyngeal transoral robotic surgery (TORS), the base of tongue (BOT) and the tonsil, as well as identify preoperative imaging characteristics that predispose toward positive margins. Study Design Case series with chart review. Setting Tertiary care referral center. Subjects and Methods We compared the final and intraoperative positive margin rate between TORS resections for tonsil and BOT oropharyngeal squamous cell carcinoma (OPSCC), as well as the effect of margins on treatment. A blinded neuroradiologist examined the preoperative imaging of BOT tumors to measure their dimensions and patterns of spread and provided a prediction of final margin results. Results Between January 2010 and May 2016, a total of 254 patients underwent TORS for OPSCC. A total of 140 patients who underwent TORS for T1/T2 OPSCC met inclusion criteria. A final positive margin is significantly more likely for BOT tumors than tonsil tumors (19.6% vs 4.5%, respectively, P = .004) and likewise for intraoperative margins of BOT and tonsil tumors (35.3% vs 12.4%, respectively; P = .002). A positive final margin is 10 times more likely to receive chemoradiation compared to a negative margin, controlling for extracapsular spread and nodal status (odds ratio, 9.6; 95% confidence interval, 1.6-59.6; P = .02). Preoperative imaging characteristics and subjective radiologic examination of BOT tumors did not correlate with final margin status. Conclusion Positive margins are significantly more likely during TORS BOT resections compared to tonsil resections. More research is needed to help surgeons predict which T1/T2 tumors will be difficult to completely extirpate.

Marginal Lands: Concept, Assessment and Management

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

Kang, Shujiang; Post, Wilfred M; West, Tristram O.

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.

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…

Spectrally Encoded Confocal Microscopy (SECM) for Diagnosing of Breast Cancer in Excision and Margin Specimens

PubMed Central

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

2016-01-01

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 intra-operatively. 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 sub-cellular resolution and accurately determine margin status intra-operatively. In this paper, in order to test feasibility of using SECM for intra-operative 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 a 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 intra-operative margin assessment tool for guiding breast cancer excisions. PMID:26779830

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

Based 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.

Achievement orientation and fear of success in Asian American college students.

PubMed

Lew, A S; Allen, R; Papouchis, N; Ritzler, B

1998-01-01

One hundred eighty-five Asian American undergraduates participated in a study designed to examine the relationships among gender, acculturation, achievement orientation, and fear of academic success. Acculturation was modestly correlated with achievement orientation. Endorsement of Asian and Anglo values were significantly related to individual-oriented achievement. Marginal significance, however, was obtained for endorsement of Asian values and beliefs to social-oriented achievement. These findings suggest that persons with a bicultural identity tend to adopt a multifaceted achievement style. Achievement orientation, in turn, predicted fear of academic success, with gender and perceived discrepancies from parental achievement values contributing minimal additional variance. Social-oriented achievement was related to high fear of academic success, whereas an individualistic orientation buffered against such conflicts.

Comparing vaccines: a systematic review of the use of the non-inferiority margin in vaccine trials.

PubMed

Donken, R; de Melker, H E; Rots, N Y; Berbers, G; Knol, M J

2015-03-17

Non-inferiority (NI) randomized controlled trials (RCTs) aim to demonstrate that a new treatment is no worse than a comparator that has already shown its efficacy over placebo within a pre-specified margin. However, clear guidelines on how the NI margin should be determined are lacking for vaccine trials. A difference (seroprevalence/risk) of 10% or a geometric mean titre/concentration (GMT) ratio of 1.5 or 2.0 in antibody levels is implicitly recommended for vaccine trials. We aimed to explore which NI margins were used in vaccine RCTs and how they were determined. A systematic search for NI vaccine RCTs yielded 177 eligible articles. Data were extracted from these articles using a standardized form and included general characteristics and characteristics specific for NI trials. Relations between the study characteristics and the NI margin used were explored. Among the 143 studies using an NI margin based on difference (n=136 on immunogenicity, n=2 on efficacy and n=5 on safety), 66% used a margin of 10%, 23% used margins lower than 10% (range 1-7.5%) and 11% used margins larger than 10% (range 11.5-25%). Of the 103 studies using a NI margin based on the GMT ratio, 50% used a margin of 0.67/1.5 and 49% used 0.5/2.0. As observed, 85% of the studies did not discuss the method of margin determination; and 19% of the studies lacked a confidence interval or p-value for non-inferiority. Most NI vaccine RCTs used an NI margin of 10% for difference or a GMT ratio of 1.5 or 2.0 without a clear rationale. Most articles presented enough information for the reader to make a judgement about the NI margin used and the conclusions. The reporting on the design, margins used and results of NI vaccine trials could be improved; more explicit guidelines may help to achieve this end. Copyright © 2015 Elsevier Ltd. All rights reserved.

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.

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…

Marginal abatement cost curves for NOx that account for ...

EPA Pesticide Factsheets

A marginal abatement cost curve (MACC) traces out the relationship between the quantity of pollution abated and the marginal cost of abating each additional unit. In the context of air quality management, MACCs typically are developed by sorting end-of-pipe controls by their respective cost effectiveness. Alternative measures, such as renewable electricity, energy efficiency, and fuel switching (RE/EE/FS), are not considered as it is difficult to quantify their abatement potential. In this paper, we demonstrate the use of an energy system model to develop a MACC for nitrogen oxides (NOx) that incorporates both end-of-pipe controls and these alternative measures. We decompose the MACC by sector, and evaluate the cost-effectiveness of RE/EE/FS relative to end-of-pipe controls. RE/EE/FS are shown to produce considerable emission reductions after end-of-pipe controls have been exhausted. Furthermore, some RE/EE/FS are shown to be cost-competitive with end-of-pipe controls. Demonstrate how the MARKAL energy system model can be used to evaluate the potential role of renewable electricity, energy efficiency and fuel switching (RE/EE/FS) in achieving NOx reductions. For this particular analysis, we show that RE/EE/FSs are able to increase the quantity of NOx reductions available for a particular marginal cost (ranging from $5k per ton to $40k per ton) by approximately 50%.

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…

Decoding the Margins: What Can the Fractal Geometry of Basaltic Flow Margins Tell Us?

NASA Astrophysics Data System (ADS)

Schaefer, E. I.; Hamilton, C.; Neish, C.; Beard, S. P.; Bramson, A. M.; Sori, M.; Rader, E. L.

2016-12-01

Studying lava flows on other planetary bodies is essential to characterizing eruption styles and constraining the bodies' thermal evolution. Although planetary basaltic flows are common, many key features are not resolvable in orbital imagery. We are thus developing a technique to characterize basaltic flow type, sub-meter roughness, and sediment mantling from these data. We will present the results from upcoming fieldwork at Craters of the Moon National Monument and Preserve with FINESSE (August) and at Hawai'i Volcanoes National Park (September). We build on earlier work that showed that basaltic flow margins are approximately fractal [Bruno et al., 1992; Gaonac'h et al., 1992] and that their fractal dimensions (D) have distinct `a`ā and pāhoehoe ranges under simple conditions [Bruno et al., 1994]. Using a differential GPS rover, we have recently shown that the margin of Iceland's 2014 Holuhraun flow exhibits near-perfect (R2=0.9998) fractality for ≥24 km across dm to km scales [Schaefer et al., 2016]. This finding suggests that a fractal-based technique has significant potential to characterize flows at sub-resolution scales. We are simultaneously seeking to understand how margin fractality can be modified. A preliminary result for an `a'ā flow in Hawaii's Ka'ū Desert suggests that although aeolian mantling obscures the original flow margin, the apparent margin (i.e., sediment-lava interface) remains fractal [Schaefer et al., 2015]. Further, the apparent margin's D is likely significantly modified from that of the original margin. Other factors that we are exploring include erosion, transitional flow types, and topographic confinement. We will also rigorously test the intriguing possibility that margin D correlates with the sub-meter Hurst exponent H of the flow surface, a common metric of roughness scaling [e.g., Shepard et al., 2001]. This hypothesis is based on geometric arguments [Turcotte, 1997] and is qualitatively consistent with all results so far.

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. Copyright © 2015 John Wiley & Sons, Ltd.

Geophysical constraints on geodynamic processes at convergent margins: A global perspective

NASA Astrophysics Data System (ADS)

Artemieva, Irina; Thybo, Hans; Shulgin, Alexey

2016-04-01

convergence rate. (4) Local isostasy is not satisfied at the convergent margins as evidenced by strong free air gravity anomalies of positive and negative signs. However, near-isostatic equilibrium may exist in broad zones of distributed deformation such as Tibet. (5) No systematic patterns are recognized in heat flow data due to strong heterogeneity of measured values which are strongly affected by hydrothermal circulation, magmatic activity, crustal faulting, horizontal heat transfer, and also due to low number of heat flow measurements across many margins. (6) Low upper mantle Vs seismic velocities beneath the convergent margins are restricted to the upper 150 km and may be related to mantle wedge melting which is confined to shallow mantle levels. Artemieva, I.M., Thybo, H., and Shulgin, A., 2015. Geophysical constraints on geodynamic processes at convergent margins: A global perspective. Gondwana Research, http://dx.doi.org/10.1016/j.gr.2015.06.010

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

PubMed

Hadjiosif, Alkis M; Smith, Maurice A

2015-06-17

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. Copyright © 2015 the authors 0270-6474/15/359106-16$15.00/0.

Assessment of margins in resection specimens for head and neck malignancies.

PubMed

Janjua, Omer Sefvan; Ahmed, Waseem; Qureshi, Sana Mehmood; Khan, Tariq Sarfaraz; Ahmed, Ashfaq; Alamgir, Wajiha

2013-04-01

To determine the relative frequency of clear, close and involved margins in resection specimens for head and neck malignancies. An observational study. The Department of Oral and Maxillofacial Surgery, Armed Forces Institute of Dentistry, Rawalpindi and the Department of Histopathology, Armed Forces Institute of Pathology, Rawalpindi, from January 2008 to December 2010. Tumour registers and computer data bases in the department of Histopathology of Armed Forces Institute of Pathology, Rawalpindi, were analyzed for the cases of malignancies involving head and neck region that were sent for histopathological analysis after resection in the last three years. Histopathology reports were obtained. The data regarding age, gender, site, type of malignancy and margin status (clear, close or involved) was recorded on specially designed proformas for the study and later on analyzed by using SPSS version 17.0. Results were expressed. A total of 319 cases were registered in the study duration. The age of the patients ranged from 22-90 years (mean 59.5 + 14.1 years). Male to female ratio was 1.53:1. One hundred and thirty six (42.6%) were squamous cell carcinoma (SCC), 163 were basal cell carcinomas (BCC, 51.0%); the rest included 18 salivary gland malignancies (5.7%) and one carcino-sarcoma (0.31%) and chondrosarcoma each. All margins were found clear in 137 patients (42.9%); involved in 168 cases (52.7%) and close in 14 cases (4.4%). Margin clearance could not be achieved in more than 50% cases, this can lead to poor prognosis. Hence, methods should be adopted to improve the margin clearance in various head and neck malignancies.

Fast growing research on negative emissions

NASA Astrophysics Data System (ADS)

Minx, Jan C.; Lamb, William F.; Callaghan, Max W.; Bornmann, Lutz; Fuss, Sabine

2017-03-01

Generating negative emissions by removing carbon dioxide from the atmosphere is a key requirement for limiting global warming to well below 2 °C, or even 1.5 °C, and therefore for achieving the long-term climate goals of the recent Paris Agreement. Despite being a relatively young topic, negative emission technologies (NETs) have attracted growing attention in climate change research over the last decade. A sizeable body of evidence on NETs has accumulated across different fields that is by today too large and too diverse to be comprehensively tracked by individuals. Yet, understanding the size, composition and thematic structure of this literature corpus is a crucial pre-condition for effective scientific assessments of NETs as, for example, required for the new special report on the 1.5 °C by the Intergovernmental Panel on Climate Change (IPCC). In this paper we use scientometric methods and topic modelling to identify and characterize the available evidence on NETs as recorded in the Web of Science. We find that the development of the literature on NETs has started later than for climate change as a whole, but proceeds more quickly by now. A total number of about 2900 studies have accumulated between 1991 and 2016 with almost 500 new publications in 2016. The discourse on NETs takes place in distinct communities around energy systems, forests as well as biochar and other soil carbon options. Integrated analysis of NET portfolios—though crucial for understanding how much NETs are possible at what costs and risks—are still in their infancy and do not feature as a theme across the literature corpus. Overall, our analysis suggests that NETs research is relatively marginal in the wider climate change discourse despite its importance for global climate policy.

Dermatofibrosarcoma protuberans of the vulva: margins assessment and reconstructive options - a report of two cases.

PubMed

Bertolli, Eduardo; Bretchbuhl, Eduard Renè; Camarço, William Ricardo; Campagnari, Mariane; Molina, André Sapata; Baiocchi, Glauco; Macedo, Mariana Petaccia; Pinto, Clovis Antonio; Cunha, Isabela Werneck; Neto, João Pedreira

2014-12-29

Dermatofibrosarcoma Protuberans (DFSP) of the vulva is rare and oncologic surgery with free margins may lead to severe functional damage, requiring multidisciplinary approach regarding resection, margin assessment and reconstruction.Case Report: Two cases of DFSP in vulva were treated in a single institution. A 28-year-old patient with an incisional biopsy in the vulvar region revealing DFSP underwent a partial vulvectomy with clitoris preservation. Pathological studies revealed free margins and reconstructive surgery was performed. This patient is disease free in a 40 months follow up. The other, a 57-year-old patient was also referred after an incomplete resection of a DFSP in the vulvar region. A 1-cm margim resection followed by Complete Circumferential and Peripheral Deep Margin Assessment (CCPDMA) was performed. Although the upper lateral margin was positive, it was possible to perform another wide local excision with preservation of the clitoris and primary closure. DFSP of the vulva requires an accurate evaluation of margins, resections following oncological principles and reconstruction. Although being a very challenging lesion that usually implies difficult surgical management, if treated in a multidisciplinary environment, with surgical oncologists, experienced dermatopathologists and reconstructive surgeons can achieve good results. Even in difficult cases that presents with large lesions and compromising challenging areas, a complete oncologic resection can be performed minimizing functional damage for the patient.

Marginal Accuracy and Internal Fit of 3-D Printing Laser-Sintered Co-Cr Alloy Copings.

PubMed

Kim, Myung-Joo; Choi, Yun-Jung; Kim, Seong-Kyun; Heo, Seong-Joo; Koak, Jai-Young

2017-01-23

Laser sintered technology has been introduced for clinical use and can be utilized more widely, accompanied by the digitalization of dentistry and the development of direct oral scanning devices. This study was performed with the aim of comparing the marginal accuracy and internal fit of Co-Cr alloy copings fabricated by casting, CAD/CAM (Computer-aided design/Computer-assisted manufacture) milled, and 3-D laser sintered techniques. A total of 36 Co-Cr alloy crown-copings were fabricated from an implant abutment. The marginal and internal fit were evaluated by measuring the weight of the silicone material, the vertical marginal discrepancy using a microscope, and the internal gap in the sectioned specimens. The data were statistically analyzed by One-way ANOVA (analysis of variance), a Scheffe's test, and Pearson's correlation at the significance level of p = 0.05, using statistics software. The silicone weight was significantly low in the casting group. The 3-D laser sintered group showed the highest vertical discrepancy, and marginal-, occlusal-, and average- internal gaps ( p < 0.05). The CAD/CAM milled group revealed a significantly high axial internal gap. There are moderate correlations between the vertical marginal discrepancy and the internal gap variables ( r = 0.654), except for the silicone weight. In this study, the 3-D laser sintered group achieved clinically acceptable marginal accuracy and internal fit.

Marginal Accuracy and Internal Fit of 3-D Printing Laser-Sintered Co-Cr Alloy Copings

PubMed Central

Kim, Myung-Joo; Choi, Yun-Jung; Kim, Seong-Kyun; Heo, Seong-Joo; Koak, Jai-Young

2017-01-01

Laser sintered technology has been introduced for clinical use and can be utilized more widely, accompanied by the digitalization of dentistry and the development of direct oral scanning devices. This study was performed with the aim of comparing the marginal accuracy and internal fit of Co-Cr alloy copings fabricated by casting, CAD/CAM (Computer-aided design/Computer-assisted manufacture) milled, and 3-D laser sintered techniques. A total of 36 Co-Cr alloy crown-copings were fabricated from an implant abutment. The marginal and internal fit were evaluated by measuring the weight of the silicone material, the vertical marginal discrepancy using a microscope, and the internal gap in the sectioned specimens. The data were statistically analyzed by One-way ANOVA (analysis of variance), a Scheffe’s test, and Pearson’s correlation at the significance level of p = 0.05, using statistics software. The silicone weight was significantly low in the casting group. The 3-D laser sintered group showed the highest vertical discrepancy, and marginal-, occlusal-, and average- internal gaps (p < 0.05). The CAD/CAM milled group revealed a significantly high axial internal gap. There are moderate correlations between the vertical marginal discrepancy and the internal gap variables (r = 0.654), except for the silicone weight. In this study, the 3-D laser sintered group achieved clinically acceptable marginal accuracy and internal fit. PMID:28772451

Reproducing normative and marginalized masculinities: adolescent male popularity and the outcast.

PubMed

Phillips, Debby A

2005-09-01

Every day, in professional work and in our personal lives, we reproduce by words and behaviors particular understandings of life and how it works. This includes understandings about what is 'normal' and 'not normal' masculinity and who are 'normal' and 'not normal' boys and men. Being marginalized or outcast from the norm is rarely a free choice. The language that constructs normal and abnormal is not innocent and does not simply arrive in our minds transparently reflected in our behavior or in our client advice or student education. Examining words and behaviors from adolescent boys and from media sources, this research explores the role of cultural discourses in producing normative and marginalized masculinities. It builds upon recent scholarship that questions cultural prescriptions for masculinity and traditional male norms. Feminist, poststructural, psychoanalytic discourse analysis and multiple methods were used to explore links between cultural discourses of masculinity and performativity of masculinity. Practices of heterosexuality, homophobia, athleticism, economic privilege, toughness, and violence provided pathways toward achieving and/or maintaining status as the hegemonic masculine norm in adolescence. 'Popularity' signified the norm and 'outcasts' from the norm signified marginalized masculinities.

Achievement Emotions and Academic Performance: Longitudinal Models of Reciprocal Effects.

PubMed

Pekrun, Reinhard; Lichtenfeld, Stephanie; Marsh, Herbert W; Murayama, Kou; Goetz, Thomas

2017-09-01

A reciprocal effects model linking emotion and achievement over time is proposed. The model was tested using five annual waves of the Project for the Analysis of Learning and Achievement in Mathematics (PALMA) longitudinal study, which investigated adolescents' development in mathematics (Grades 5-9; N = 3,425 German students; mean starting age = 11.7 years; representative sample). Structural equation modeling showed that positive emotions (enjoyment, pride) positively predicted subsequent achievement (math end-of-the-year grades and test scores), and that achievement positively predicted these emotions, controlling for students' gender, intelligence, and family socioeconomic status. Negative emotions (anger, anxiety, shame, boredom, hopelessness) negatively predicted achievement, and achievement negatively predicted these emotions. The findings were robust across waves, achievement indicators, and school tracks, highlighting the importance of emotions for students' achievement and of achievement for the development of emotions. © 2017 The Authors. Child Development © 2017 Society for Research in Child Development, Inc.

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 Margin...

Changes in ice-margin processes and sediment routing during ice-sheet advance across a marginal moraine

USGS Publications Warehouse

Knight, P.G.; Jennings, C.E.; Waller, R.I.; Robinson, Z.P.

2007-01-01

Advance of part of the margin of the Greenland ice sheet across a proglacial moraine ridge between 1968 and 2002 caused progressive changes in moraine morphology, basal ice formation, debris release, ice-marginal sediment storage, and sediment transfer to the distal proglacial zone. When the ice margin is behind the moraine, most of the sediment released from the glacier is stored close to the ice margin. As the margin advances across the moraine the potential for ice-proximal sediment storage decreases and distal sediment flux is augmented by reactivation of moraine sediment. For six stages of advance associated with distinctive glacial and sedimentary processes we describe the ice margin, the debris-rich basal ice, debris release from the glacier, sediment routing into the proglacial zone, and geomorphic processes on the moraine. The overtopping of a moraine ridge is a significant glaciological, geomorphological and sedimentological threshold in glacier advance, likely to cause a distinctive pulse in distal sediment accumulation rates that should be taken into account when glacial sediments are interpreted to reconstruct glacier fluctuations. ?? 2007 Swedish Society for Anthropology and Geography.

Rural Transient Children and School Achievement: An Australian Perspective.

ERIC Educational Resources Information Center

Birch, Ian; Lally, Mike

1994-01-01

Among 336 students aged 4-8 in 4 rural Australian schools, transient students scored marginally lower on ability tests than their residentially stable peers. However, teachers gave more weight to family background and support, as opposed to disruption of schooling, as influencing children's adjustment to change and school achievement. (LP)

Optic nerve gliomas: role of Ki-67 staining of tumour and margins in predicting long-term outcome.

PubMed

Yeung, Sonia N; White, Valerie A; Nimmo, Michael; Rootman, Jack

2011-08-01

Although optic nerve gliomas (ONGs) are generally slow-growing with a good prognosis, factors for identifying cases that may pursue a more aggressive course are not well established. The authors investigated cell proliferation markers for prognostic significance in a series of resected ONGs. Twelve cases of resected ONG were identified out of a total of 38 examined at the authors' institution between 1981 and 2008. Clinical data were reviewed. Ki-67 and p53 immunohistochemical staining was performed on the tumour mass and the proximal resection margin. All of the tumours were low-grade pilocytic astrocytomas. Six patients were suspected to have histologically positive proximal resection margins. Ki-67 labelling indices (LI) ranged from 0.3% to 5.9% (mean 2.4%) for the tumour mass and from 0 to 2.1% (mean 0.9%) for the proximal resection margins. One patient had evidence of progression 25 months after subtotal surgical resection. The Ki-67 LI of the proximal resection margin in this case was similar to the main tumour value. The other six patients with histologically negative proximal resection margins all had lower relative proliferation indices at the resection margin when compared with the tumour mass and are currently stable with no evidence of progression. Routine histological examination of resection margins may be difficult to interpret in the setting of reactive gliosis. A resection margin with a Ki-67 LI similar to the tumour bulk value may have an adjunctive role in identifying cases with the potential for growth thereby facilitating the decision-making process for future management and surveillance.

Extensional Fault Evolution and its Flexural Isostatic Response During Iberia-Newfoundland Rifted Margin Formation

NASA Astrophysics Data System (ADS)

Gómez-Romeu, J.; Kusznir, N.; Manatschal, G.; Roberts, A.

2017-12-01

During the formation of magma-poor rifted margins, upper lithosphere thinning and stretching is achieved by extensional faulting, however, there is still debate and uncertainty how faults evolve during rifting leading to breakup. Seismic data provides an image of the present-day structural and stratigraphic configuration and thus initial fault geometry is unknown. To understand the geometric evolution of extensional faults at rifted margins it is extremely important to also consider the flexural response of the lithosphere produced by fault displacement resulting in footwall uplift and hangingwall subsidence. We investigate how the flexural isostatic response to extensional faulting controls the structural development of rifted margins. To achieve our aim, we use a kinematic forward model (RIFTER) which incorporates the flexural isostatic response to extensional faulting, crustal thinning, lithosphere thermal loads, sedimentation and erosion. Inputs for RIFTER are derived from seismic reflection interpretation and outputs of RIFTER are the prediction of the structural and stratigraphic consequences of recursive sequential faulting and sedimentation. Using RIFTER we model the simultaneous tectonic development of the Iberia-Newfoundland conjugate rifted margins along the ISE01-SCREECH1 and TGS/LG12-SCREECH2 seismic lines. We quantitatively test and calibrate the model against observed target data restored to breakup time. Two quantitative methods are used to obtain this target data: (i) gravity anomaly inversion which predicts Moho depth and continental lithosphere thinning and (ii) reverse post-rift subsidence modelling to give water and Moho depths at breakup time. We show that extensional faulting occurs on steep ( 60°) normal faults in both proximal and distal parts of rifted margins. Extensional faults together with their flexural isostatic response produce not only sub-horizontal exhumed footwall surfaces (i.e. the rolling hinge model) and highly rotated (60�

Post-fire ecohydrological conditions at peatland margins in different hydrogeological settings of the Boreal Plain

NASA Astrophysics Data System (ADS)

Lukenbach, M. C.; Hokanson, K. J.; Devito, K. J.; Kettridge, N.; Petrone, R. M.; Mendoza, C. A.; Granath, G.; Waddington, J. M.

2017-05-01

In the Boreal Plain of Canada, the margins of peatland ecosystems that regulate solute and nutrient fluxes between peatlands and adjacent mineral uplands are prone to deep peat burning. Whether post-fire carbon accumulation is able to offset large carbon losses associated with the deep burning at peatland margins is unknown. For this reason, we examined how post-fire hydrological conditions (i.e. water table depth and periodicity, soil tension, and surface moisture content) and depth of burn were associated with moss recolonization at the peatland margins of three sites. We then interpreted these findings using a hydrogeological systems approach, given the importance of groundwater in determining conditions in the soil-plant-atmosphere continuum in peatlands. Peatland margins dominated by local groundwater flow from adjacent peatland middles were characterized by dynamic hydrological conditions that, when coupled with lowered peatland margin surface elevations due to deep burning, produced two common hydrological states: 1) flooding during wet periods and 2) rapid water table declines during dry periods. These dynamic hydrological states were unfavorable to peatland moss recolonization and bryophytes typical of post-fire recovery in mineral uplands became established. In contrast, at a peatland margin where post-fire hydrological conditions were moderated by larger-scale groundwater flow, flooding and rapid water table declines were infrequent and, subsequently, greater peatland-dwelling moss recolonization was observed. We argue that peatland margins poorly connected to larger-scale groundwater flow are not only prone to deep burning but also lags in post-fire moss recovery. Consequently, an associated reduction in post-fire peat accumulation may occur and negatively affect the net carbon sink status and ecohydrological and biogeochemical function of these peatlands.

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…

Splenic marginal zone lymphoma.

PubMed

Piris, Miguel A; Onaindía, Arantza; Mollejo, Manuela

Splenic marginal zone lymphoma (SMZL) is an indolent small B-cell lymphoma involving the spleen and bone marrow characterized by a micronodular tumoral infiltration that replaces the preexisting lymphoid follicles and shows marginal zone differentiation as a distinctive finding. SMZL cases are characterized by prominent splenomegaly and bone marrow and peripheral blood infiltration. Cells in peripheral blood show a villous cytology. Bone marrow and peripheral blood characteristic features usually allow a diagnosis of SMZL to be performed. Mutational spectrum of SMZL identifies specific findings, such as 7q loss and NOTCH2 and KLF2 mutations, both genes related with marginal zone differentiation. There is a striking clinical variability in SMZL cases, dependent of the tumoral load and performance status. Specific molecular markers such as 7q loss, p53 loss/mutation, NOTCH2 and KLF2 mutations have been found to be associated with the clinical variability. Distinction from Monoclonal B-cell lymphocytosis with marginal zone phenotype is still an open issue that requires identification of precise and specific thresholds with clinical meaning. Copyright © 2016 Elsevier Ltd. All rights reserved.

The sociocultural model of eating disorders in Mexican American women: behavioral acculturation and cognitive marginalization as moderators.

PubMed

Warren, Cortney S; Castillo, Linda G; Gleaves, David H

2010-01-01

White American cultural values of appearance are implicated in the development of body dissatisfaction. This study examined whether the relationships between awareness of White American appearance ideals, internalization of such ideals, and body dissatisfaction are moderated by behavioral acculturation and attitudinal marginalization in a sample of 94 Mexican American women. Results indicated that behavioral acculturation moderated the relationship between awareness and internalization and cognitive marginalization moderated the relationship between internalization and body dissatisfaction. Body size was positively correlated with body dissatisfaction and negatively correlated with behavioral acculturation. These findings have important implications for clinical practice and research with Mexican American women.

How does achievement motivation influence mental effort mobilization? Physiological evidence of deteriorative effects of negative affects on the level of engagement.

PubMed

Capa, Rémi L; Audiffren, Michel

2009-12-01

We tested whether the effect of achievement motivation on effort is modulated by two possible factors of the motivational intensity theory (Wright and Kirby, 2001): perceived difficulty and maximally justified effort. Approach-driven (N=16) and avoidance-driven (N=16) participants were first instructed to perform a reaction time task to the best of their abilities. Next, the participants were instructed to consistently beat their performance standard established in the first condition. Approach-driven participants showed a stronger decrease of midfrequency band of heart rate variability, which was used as an index of mental effort, than avoidance-driven participants in the second instruction condition. Moreover, avoidance-driven participants showed a higher corrugator supercilii reactivity, which was used as an index of negative affects, than approach-driven participants in the second instruction condition. No difference of perceived difficulty between groups was observed. Results suggested that avoidance-driven participants developed negative affects in the second instruction condition decreasing the maximally justified effort and their level of engagement.

Re-appraisal of the Magma-rich versus Magma-poor Paradigm at Rifted Margins: consequences for breakup processes

NASA Astrophysics Data System (ADS)

Tugend, J.; Gillard, M.; Manatschal, G.; Nirrengarten, M.; Harkin, C. J.; Epin, M. E.; Sauter, D.; Autin, J.; Kusznir, N. J.; McDermott, K.

2017-12-01

Rifted margins are often classified based on their magmatic budget only. Magma-rich margins are commonly considered to have excess decompression melting at lithospheric breakup compared with steady state seafloor spreading while magma-poor margins have suppressed melting. New observations derived from high quality geophysical data sets and drill-hole data have revealed the diversity of rifted margin architecture and variable distribution of magmatism. Recent studies suggest, however, that rifted margins have more complex and polyphase tectono-magmatic evolutions than previously assumed and cannot be characterized based on the observed volume of magma alone. We compare the magmatic budget related to lithospheric breakup along two high-resolution long-offset deep reflection seismic profiles across the SE-Indian (magma-poor) and Uruguayan (magma-rich) rifted margins. Resolving the volume of magmatic additions is difficult. Interpretations are non-unique and several of them appear plausible for each case involving variable magmatic volumes and mechanisms to achieve lithospheric breakup. A supposedly 'magma-poor' rifted margin (SE-India) may show a 'magma-rich' lithospheric breakup whereas a 'magma-rich' rifted margin (Uruguay) does not necessarily show excess magmatism at lithospheric breakup compared with steady-state seafloor spreading. This questions the paradigm that rifted margins can be subdivided in either magma-poor or magma-rich margins. The Uruguayan and other magma-rich rifted margins appear characterized by an early onset of decompression melting relative to crustal breakup. For the converse, where the onset of decompression melting is late compared with the timing of crustal breakup, mantle exhumation can occur (e.g. SE-India). Our work highlights the difficulty in determining a magmatic budget at rifted margins based on seismic reflection data alone, showing the limitations of margin classification based solely on magmatic volumes. The timing of

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-operatively.

Excision margins and sentinel lymph node status as prognostic factors in thick melanoma of the head and neck: A retrospective analysis.

PubMed

Ruskin, Olivia; Sanelli, Alexandra; Herschtal, Alan; Webb, Angela; Dixon, Ben; Pohl, Miklos; Donahoe, Simon; Spillane, John; Henderson, Michael A; Gyorki, David E

2016-09-01

Recommended margins for thick cutaneous melanoma (Breslow thickness >4 mm; T4) have decreased over recent decades. Optimal margins and the role of sentinel node biopsy (SNB) in thick head and neck melanoma remain controversial. A single-center review was conducted of patients treated between 2002 and 2012 assessing the impact of excision margins and sentinel lymph node status on locoregional recurrence and melanoma-specific survival (MSS). One hundred eight patients were identified. Median age was 71.1 years and median Breslow thickness was 6.0 mm. Median follow-up was 40 months. Locoregional recurrence occurred in 27% and there was no significant reduction in recurrence with margins ≥2 cm (p = .17). Increasing margins did not improve survival (p = .58). Fifty-nine patients (55%) underwent SNB, of which 27% were positive. There was a trend toward longer survival for patients who were sentinel lymph node-negative (p = .097). Wider margins do not significantly improve locoregional recurrence or MSS. Sentinel lymph node involvement reflects a poor prognosis. © 2016 Wiley Periodicals, Inc. Head Neck 38: 1373-1379, 2016. © 2016 Wiley Periodicals, Inc.

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

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

Wakai, Nobuhide, E-mail: wakai@naramed-u.ac.jp; Sumida, Iori; Otani, Yuki

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 indexmore » (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

Marginalized zero-altered models for longitudinal count data.

PubMed

Tabb, Loni Philip; Tchetgen, Eric J Tchetgen; Wellenius, Greg A; Coull, Brent A

2016-10-01

Count data often exhibit more zeros than predicted by common count distributions like the Poisson or negative binomial. In recent years, there has been considerable interest in methods for analyzing zero-inflated count data in longitudinal or other correlated data settings. A common approach has been to extend zero-inflated Poisson models to include random effects that account for correlation among observations. However, these models have been shown to have a few drawbacks, including interpretability of regression coefficients and numerical instability of fitting algorithms even when the data arise from the assumed model. To address these issues, we propose a model that parameterizes the marginal associations between the count outcome and the covariates as easily interpretable log relative rates, while including random effects to account for correlation among observations. One of the main advantages of this marginal model is that it allows a basis upon which we can directly compare the performance of standard methods that ignore zero inflation with that of a method that explicitly takes zero inflation into account. We present simulations of these various model formulations in terms of bias and variance estimation. Finally, we apply the proposed approach to analyze toxicological data of the effect of emissions on cardiac arrhythmias.

Marginalized zero-altered models for longitudinal count data

PubMed Central

Tabb, Loni Philip; Tchetgen, Eric J. Tchetgen; Wellenius, Greg A.; Coull, Brent A.

2015-01-01

Count data often exhibit more zeros than predicted by common count distributions like the Poisson or negative binomial. In recent years, there has been considerable interest in methods for analyzing zero-inflated count data in longitudinal or other correlated data settings. A common approach has been to extend zero-inflated Poisson models to include random effects that account for correlation among observations. However, these models have been shown to have a few drawbacks, including interpretability of regression coefficients and numerical instability of fitting algorithms even when the data arise from the assumed model. To address these issues, we propose a model that parameterizes the marginal associations between the count outcome and the covariates as easily interpretable log relative rates, while including random effects to account for correlation among observations. One of the main advantages of this marginal model is that it allows a basis upon which we can directly compare the performance of standard methods that ignore zero inflation with that of a method that explicitly takes zero inflation into account. We present simulations of these various model formulations in terms of bias and variance estimation. Finally, we apply the proposed approach to analyze toxicological data of the effect of emissions on cardiac arrhythmias. PMID:27867423

The marginal band system in nymphalid butterfly wings.

PubMed

Taira, Wataru; Kinjo, Seira; Otaki, Joji M

2015-01-01

Butterfly wing color patterns are highly complex and diverse, but they are believed to be derived from the nymphalid groundplan, which is composed of several color pattern systems. Among these pattern systems, the marginal band system, including marginal and submarginal bands, has rarely been studied. Here, we examined the color pattern diversity of the marginal band system among nymphalid butterflies. Marginal and submarginal bands are usually expressed as a pair of linear bands aligned with the wing margin. However, a submarginal band can be expressed as a broken band, an elongated oval, or a single dot. The marginal focus, usually a white dot at the middle of a wing compartment along the wing edge, corresponds to the pupal edge spot, one of the pupal cuticle spots that signify the locations of color pattern organizing centers. A marginal band can be expressed as a semicircle, an elongated oval, or a pair of eyespot-like structures, which suggest the organizing activity of the marginal focus. Physical damage at the pupal edge spot leads to distal dislocation of the submarginal band in Junonia almana and in Vanessa indica, suggesting that the marginal focus functions as an organizing center for the marginal band system. Taken together, we conclude that the marginal band system is developmentally equivalent to other symmetry systems. Additionally, the marginal band is likely a core element and the submarginal band a paracore element of the marginal band system, and both bands are primarily specified by the marginal focus organizing center.

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. Published by Elsevier B.V.

Geomorphology of the Iberian Continental Margin

NASA Astrophysics Data System (ADS)

Maestro, Adolfo; López-Martínez, Jerónimo; Llave, Estefanía; Bohoyo, Fernando; Acosta, Juan; Hernández-Molina, F. Javier; Muñoz, Araceli; Jané, Gloria

2013-08-01

The submarine features and processes around the Iberian Peninsula are the result of a complex and diverse geological and oceanographical setting. This paper presents an overview of the seafloor geomorphology of the Iberian Continental Margin and the adjacent abyssal plains. The study covers an area of approximately 2.3 million km2, including a 50 to 400 km wide band adjacent to the coastline. The main morphological characteristics of the seafloor features on the Iberian continental shelf, continental slope, continental rise and the surrounding abyssal plains are described. Individual seafloor features existing on the Iberian Margin have been classified into three main groups according to their origin: tectonic and/or volcanic, depositional and erosional. Major depositional and erosional features around the Iberian Margin developed in late Pleistocene-Holocene times and have been controlled by tectonic movements and eustatic fluctuations. The distribution of the geomorphological features is discussed in relation to their genetic processes and the evolution of the margin. The prevalence of one or several specific processes in certain areas reflects the dominant morphotectonic and oceanographic controlling factors. Sedimentary processes and the resulting depositional products are dominant on the Valencia-Catalán Margin and in the northern part of the Balearic Promontory. Strong tectonic control is observed in the geomorphology of the Betic and the Gulf of Cádiz margins. The role of bottom currents is especially evident throughout the Iberian Margin. The Galicia, Portuguese and Cantabrian margins show a predominance of erosional features and tectonically-controlled linear features related to faults.

Counterstereotypic Identity among High-Achieving Black Students

ERIC Educational Resources Information Center

Harpalani, Vinay

2017-01-01

This article examines how racial stereotypes affect achievement and identity formation among low income, urban Black adolescents. Specifically, the major question addressed is: how do high-achieving Black students succeed academically despite negative stereotypes of their intellectual abilities? Results indicate that high-achieving Black youth,…

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.

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…

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.

MARGINS: Toward a novel science plan

NASA Astrophysics Data System (ADS)

Mutter, John C.

A science plan to study continental margins has been in the works for the past 3 years, with almost 200 Earth scientists from a wide variety of disciplines gathering at meetings and workshops. Most geological hazards and resources are found at continental margins, yet our understanding of the processes that shape the margins is meager.In formulating this MARGINS research initiative, fundamental issues concerning our understanding of basic Earth-forming processes have arisen. It is clear that a business-as-usual approach will not solve the class of problems defined by the MARGINS program; the solutions demand approaches different from those used in the past. In many cases, a different class of experiment will be required, one that is well beyond the capability of individual principle investigators to undertake on their own. In most cases, broadly based interdisciplinary studies will be needed.

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.

Circumferential resection margin positivity after preoperative chemoradiotherapy based on magnetic resonance imaging for locally advanced rectal cancer: implication of boost radiotherapy to the involved mesorectal fascia.

PubMed

Kim, Kyung Hwan; Park, Min Jung; Lim, Joon Seok; Kim, Nam Kyu; Min, Byung Soh; Ahn, Joong Bae; Kim, Tae Il; Kim, Ho Geun; Koom, Woong Sub

2016-04-01

To identify patients who are at a higher risk of pathologic circumferential resection margin involvement using preoperative magnetic resonance imaging. Between October 2008 and November 2012, 165 patients with locally advanced rectal cancer (cT4 or cT3 with <2 mm distance from tumour to mesorectal fascia) who received preoperative chemoradiotherapy were analysed. The morphologic patterns on post-chemoradiotherapy magnetic resonance imaging were categorized into five patterns from Pattern A (most-likely negative pathologic circumferential resection margin) to Pattern E (most-likely positive pathologic circumferential resection margin). In addition, the location of mesorectal fascia involvement was classified as lateral, posterior and anterior. The diagnostic accuracy of the morphologic criteria was calculated using receiver operating characteristic curve analysis. Pathologic circumferential resection margin involvement was identified in 17 patients (10.3%). The diagnostic accuracy of predicting pathologic circumferential resection margin involvement was 0.73 using the five-scale magnetic resonance imaging pattern. The sensitivity, specificity, positive predictive value and negative predictive value for predicting pathologic circumferential resection margin involvement were 76.5, 65.5, 20.3 and 96.0%, respectively, when cut-off was set between Patterns C and D. On multivariate logistic regression, the magnetic resonance imaging patterns D and E (P= 0.005) and posterior or lateral mesorectal fascia involvement (P= 0.017) were independently associated with increased probability of pathologic circumferential resection margin involvement. The rate of pathologic circumferential resection margin involvement was 30.0% when the patient had Pattern D or E with posterior or lateral mesorectal fascia involvement. Patients who are at a higher risk of pathologic circumferential resection margin involvement can be identified using preoperative magnetic resonance imaging although

Extreme hepatic resections for the treatment of advanced hepatoblastoma: Are planned close margins an acceptable approach?

PubMed

Fonseca, Adriana; Gupta, Abha; Shaikh, Furqan; Ramphal, Raveena; Ng, Vicky; McGilvray, Ian; Gerstle, J Ted

2018-02-01

Orthotopic liver transplantation (OLT) is considered the standard for children with hepatoblastoma (HB) in whom complete surgical resection is not possible. However, OLT is not always available or feasible. To describe the outcome of children with HB who were initially deemed unresectable and underwent complex hepatectomy with planned close margins, and ultimately avoided OLT. Demographic data, surgical and pathologic details, and survival information were collected from children treated for HB between January 2010 to December 2015. Among six children (median age 12 months (3-41 months)), PRETEXT classification was III (n = 2), III/IV (n = 1), and IV (n = 3). Patients received a median of six cycles (range 4-7) of platinum-based induction chemotherapy; five received doxorubicin. Experienced pediatric surgeons performed extended right and left hepatectomy in five and one patients, respectively, with assistance of an experienced liver transplant surgeon (n = 4). Microscopic margins were positive (n = 2) and negative but close (n = 4; 2-5 mm). Two patients required vascular reconstruction of the vena cava. At median follow-up of 3.3 years (1.7-4.6 years), there was no evidence of local recurrence. One patient had recurrence of pulmonary disease 3 months after surgery. Patients with advanced HB treated with complex surgical resections with positive or close negative margins had good outcomes without OLT. We suggest that planned positive or close microscopic margins in highly selected HB patients may spare the morbidity of OLT and offer an alternative for those ineligible for OLT. Our experience illustrates the importance of a multidisciplinary team specialized in the management of liver tumors. © 2017 Wiley Periodicals, Inc.

Face recognition using total margin-based adaptive fuzzy support vector machines.

PubMed

Liu, Yi-Hung; Chen, Yen-Ting

2007-01-01

This paper presents a new classifier called total margin-based adaptive fuzzy support vector machines (TAF-SVM) that deals with several problems that may occur in support vector machines (SVMs) when applied to the face recognition. The proposed TAF-SVM not only solves the overfitting problem resulted from the outlier with the approach of fuzzification of the penalty, but also corrects the skew of the optimal separating hyperplane due to the very imbalanced data sets by using different cost algorithm. In addition, by introducing the total margin algorithm to replace the conventional soft margin algorithm, a lower generalization error bound can be obtained. Those three functions are embodied into the traditional SVM so that the TAF-SVM is proposed and reformulated in both linear and nonlinear cases. By using two databases, the Chung Yuan Christian University (CYCU) multiview and the facial recognition technology (FERET) face databases, and using the kernel Fisher's discriminant analysis (KFDA) algorithm to extract discriminating face features, experimental results show that the proposed TAF-SVM is superior to SVM in terms of the face-recognition accuracy. The results also indicate that the proposed TAF-SVM can achieve smaller error variances than SVM over a number of tests such that better recognition stability can be obtained.

Advancing land-terminating ice margin in North Greenland - characteristics, evolution, and first field measurements

NASA Astrophysics Data System (ADS)

Steiner, J. F.; Prinz, R.; Abermann, J.

2017-12-01

More than 40% of the ice sheet in North Greenland terminate on land, however the characteristics of this ice margin and response to a changing climate have so far received little attention. While land-terminating ice cliffs are a feature commonly found and studied in other regions, detailed investigations in Greenland were only carried out more than six decades ago in the Thule area (Red Rock, Northwest Greenland). These studies showed a continuous advance at one location over multiple years, while the local mass balance was reported negative. The purpose of our study is to revisit the location previously studied and extend the analysis to the complete Northern ice margin employing newly available high-resolution digital terrain models (Arctic DEM). First results show that the advance at Red Rock is indeed long-term, continuing unabated today at rates of up to several meter per year. Similar magnitudes were found for large other stretches along the ice margin. With our study we aim to show (a) the main characteristics of the land-terminating ice margin in Northern Greenland, namely its slope and aspect distribution and comparison to spatial datasets of flow velocity and mass balance and (b) to provide further explanations of physical processes driving the advance. We have therefore mapped the complete ice margin and present the first results of this analysis. First field work provides new data on energy fluxes and ice temperatures at the Red Rock site as well as high resolution DEMs obtained with the use of UAVs.

Extreme marginalization: addiction and other mental health disorders, stigma, and imprisonment

PubMed Central

Kreek, Mary Jeanne

2013-01-01

Major well-defined medical problems that are, in part, the unfortunate outcome of a negative social environment may include specific addictive diseases and other mental health disorders, in particular the affective disorders of anxiety, depression, social phobia, and post-traumatic stress syndrome. This overview touches on the topic of extreme marginalization associated with addiction and other mental health disorders, along with arrest, imprisonment, and parole. All of these are characterized by lasting stigma that hauntingly continues to impact upon each person suffering from any of these problems. PMID:21884162

Deep-sea environment and biodiversity of the West African Equatorial margin

NASA Astrophysics Data System (ADS)

Sibuet, Myriam; Vangriesheim, Annick

2009-12-01

The long-term BIOZAIRE multidisciplinary deep-sea environmental program on the West Equatorial African margin organized in partnership between Ifremer and TOTAL aimed at characterizing the benthic community structure in relation with physical and chemical processes in a region of oil and gas interest. The morphology of the deep Congo submarine channel and the sedimentological structures of the deep-sea fan were established during the geological ZAIANGO project and helped to select study sites ranging from 350 to 4800 m water depth inside or near the channel and away from its influence. Ifremer conducted eight deep-sea cruises on board research vessels between 2000 and 2005. Standardized methods of sampling together with new technologies such as the ROV Victor 6000 and its associated instrumentation were used to investigate this poorly known continental margin. In addition to the study of sedimentary environments more or less influenced by turbidity events, the discovery of one of the largest cold seeps near the Congo channel and deep coral reefs extends our knowledge of the different habitats of this margin. This paper presents the background, objectives and major results of the BIOZAIRE Program. It highlights the work achieved in the 16 papers in this special issue. This synthesis paper describes the knowledge acquired at a regional and local scale of the Equatorial East Atlantic margin, and tackles new interdisciplinary questions to be answered in the various domains of physics, chemistry, taxonomy and ecology to better understand the deep-sea environment in the Gulf of Guinea.

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

PubMed

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

2016-01-01

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. 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. 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). 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.

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

Optomotor-blind negatively regulates Drosophila eye development by blocking Jak/STAT signaling.

PubMed

Tsai, Yu-Chen; Grimm, Stefan; Chao, Ju-Lan; Wang, Shih-Chin; Hofmeyer, Kerstin; Shen, Jie; Eichinger, Fred; Michalopoulou, Theoni; Yao, Chi-Kuang; Chang, Chih-Hsuan; Lin, Shih-Han; Sun, Y Henry; Pflugfelder, Gert O

2015-01-01

Organ formation requires a delicate balance of positive and negative regulators. In Drosophila eye development, wingless (wg) is expressed at the lateral margins of the eye disc and serves to block retinal development. The T-box gene optomotor-blind (omb) is expressed in a similar pattern and is regulated by Wg. Omb mediates part of Wg activity in blocking eye development. Omb exerts its function primarily by blocking cell proliferation. These effects occur predominantly in the ventral margin. Our results suggest that the primary effect of Omb is the blocking of Jak/STAT signaling by repressing transcription of upd which encodes the Jak receptor ligand Unpaired.

Optomotor-Blind Negatively Regulates Drosophila Eye Development by Blocking Jak/STAT Signaling

PubMed Central

Tsai, Yu-Chen; Grimm, Stefan; Chao, Ju-Lan; Wang, Shih-Chin; Hofmeyer, Kerstin; Shen, Jie; Eichinger, Fred; Michalopoulou, Theoni; Yao, Chi-Kuang; Chang, Chih-Hsuan; Lin, Shih-Han; Sun, Y. Henry; Pflugfelder, Gert O.

2015-01-01

Organ formation requires a delicate balance of positive and negative regulators. In Drosophila eye development, wingless (wg) is expressed at the lateral margins of the eye disc and serves to block retinal development. The T-box gene optomotor-blind (omb) is expressed in a similar pattern and is regulated by Wg. Omb mediates part of Wg activity in blocking eye development. Omb exerts its function primarily by blocking cell proliferation. These effects occur predominantly in the ventral margin. Our results suggest that the primary effect of Omb is the blocking of Jak/STAT signaling by repressing transcription of upd which encodes the Jak receptor ligand Unpaired. PMID:25781970

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…

The Setting Time of Polyether Impression Materials after Contact with Conventional and Experimental Gingival Margin Displacement Agents.

PubMed

Nowakowska, Danuta; Raszewski, Zbigniew; Ziętek, Marek; Saczko, Jolanta; Kulbacka, Julita; Więckiewicz, Włodzimierz

2018-02-01

The compatibility of chemical gingival margin displacement agents with polyether impression materials has not been determined. The aim of this study was to evaluate the setting time of polyether impression elastomers after contact with conventional and experimental gingival displacement agents. The study compared the setting time of two polyether impression materials: medium body (Impregum Penta Soft) and light body (Impregum Garant L DuoSoft) after contact with 10 gingival displacement agents, including 5 conventional astringents (10%, 20%, and 25% aluminum chloride, 25% aluminum sulfate, and 15.5% ferric sulfate) and 5 experimental adrenergics (0.1% and 0.01% HCl-epinephrine, 0.05% HCl-tetrahydrozoline, 0.05% HCl-oxymetazoline, and 10% HCl-phenylephrine). As many as 120 specimens (60 light body and 60 medium body) were mixed with 20 μl of each of 10 gingival displacement agents, and the time to achieve maximum viscosity was measured with a viscometer. The setting times of these specimens were compared with the control group of 12 specimens, which were polymerized without contact with the displacement agents. The experiments were performed in two environments: 23°C and 37°C (± 0.1°C). Individual and average polymerization time compatibility indices (PTCI) were calculated. Data were analyzed by 2-way ANOVA (α = 0.05). The evaluated chemical displacement agents from both groups changed the setting time of light- and medium-body PE. The negative individual PTCI values achieved astringent (20% aluminum chloride) with two PE in both temperature environments. The average PTCI values of the experimental displacement agents at laboratory and intraoral temperatures were significantly higher than the conventional agents. The present findings suggest that experimental retraction agents can be recommended clinically as gingival margin displacement agents with minimal effects on the setting time of medium- and light-body polyether impression materials; however, direct

A mediation analysis of achievement motives, goals, learning strategies, and academic achievement.

PubMed

Diseth, Age; Kobbeltvedt, Therese

2010-12-01

Previous research is inconclusive regarding antecedents and consequences of achievement goals, and there is a need for more research in order to examine the joint effects of different types of motives and learning strategies as predictors of academic achievement. To investigate the relationship between achievement motives, achievement goals, learning strategies (deep, surface, and strategic), and academic achievement in a hierarchical model. Participants were 229 undergraduate students (mean age: 21.2 years) of psychology and economics at the University of Bergen, Norway. Variables were measured by means of items from the Achievement Motives Scale (AMS), the Approaches and Study Skills Inventory for Students, and an achievement goal scale. Correlation analysis showed that academic achievement (examination grade) was positively correlated with performance-approach goal, mastery goal, and strategic learning strategies, and negatively correlated with performance-avoidance goal and surface learning strategy. A path analysis (structural equation model) showed that achievement goals were mediators between achievement motives and learning strategies, and that strategic learning strategies mediated the relationship between achievement goals and academic achievement. This study integrated previous findings from several studies and provided new evidence on the direct and indirect effects of different types of motives and learning strategies as predictors of academic achievement.

Pathology of nodal marginal zone lymphomas.

PubMed

Pileri, Stefano; Ponzoni, Maurilio

Nodal marginal zone B cell lymphomas (NMZLs) are a rare group of lymphoid disorders part of the spectrum of marginal zone B-cell lymphomas, which encompass splenic marginal one B-cell lymphoma (SMZL) and extra nodal marginal zone of B-cell lymphoma (EMZL), often of MALT-type. Two clinicopathological forms of NMZL are recognized: adult-type and pediatric-type, respectively. NMZLs show overlapping features with other types of MZ, but distinctive features as well. In this review, we will focus on the salient distinguishing features of NMZL mostly under morphological/immunophenotypical/molecular perspectives in views of the recent acquisitions and forthcoming updated 2016 WHO classification of lymphoid malignancies. Copyright © 2016 Elsevier Ltd. All rights reserved.

Hierarchical Marginal Land Assessment for Land Use Planning

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

Kang, Shujiang; Post, Wilfred M; Wang, Dali

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,more » 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.« less

Instagram #instasad?: exploring associations among instagram use, depressive symptoms, negative social comparison, and strangers followed.

PubMed

Lup, Katerina; Trub, Leora; Rosenthal, Lisa

2015-05-01

As the use and influence of social networking continues to grow, researchers have begun to explore its consequences for psychological well-being. Some research suggests that Facebook use can have negative consequences for well-being. Instagram, a photo-sharing social network created in 2010, has particular characteristics that may make users susceptible to negative consequences. This study tested a theoretically grounded moderated meditation model of the association between Instagram use and depressive symptoms through the mechanism of negative social comparison, and moderation by amount of strangers one follows. One hundred and seventeen 18-29 year olds completed online questionnaires containing demographics, frequency of Instagram use, amount of strangers followed on Instagram, the Center for Epidemiological Resources Scale for Depression, and the Social Comparison Rating Scale. Instagram use was marginally positively associated with depressive symptoms, and positive social comparison was significantly negatively associated with depressive symptoms. Amount of strangers followed moderated the associations of Instagram use with social comparison (significantly) and depressive symptoms (marginally), and further significantly moderated the indirect association of Instagram use with depressive symptoms through social comparison. Findings generally suggest that more frequent Instagram use has negative associations for people who follow more strangers, but positive associations for people who follow fewer strangers, with social comparison and depressive symptoms. Implications of negative associations of social networking for people who follow strangers and the need for more research on Instagram use given its increasing popularity are explored.

Kinematic Reconstruction of the Costa Rican Margin: Evidence for Discontinuities in Deformation Across the Margin

NASA Astrophysics Data System (ADS)

Gose, B.; Bangs, N. L.; McIntosh, K. D.

2016-12-01

Recently acquired 3D seismic reflection data shows that both in-sequence and out-of sequence faults makeup the interior structure of the Costa Rican convergent margin. Recent studies have found evidence for a phase of accretion that led to the formation of a series of thrust-bounded folds that are easily observable within the margin-wedge fabric. Along a primary 2D transect through the center of the 3D survey, faults partition the outer 23km of the margin into 8 fault-bounded segments that can be divided into two characteristic zones, those closest to the trench (S1-S3) and those furthest (S4-S8) separated by a slope break 10 km from the trench (Fig 1). To better understand the observed structure, each segment was characterized as a fault-propagation fold and geometrically modeled using Paradigm's Geosec 2D software. Kinematic flexural slip modules were applied in order to perform bed-length balancing and generate a geologic reconstruction of the margin. Results show the section of the margin spanning from 3-23km from the deformation front has experienced 27.5% shortening, assuming the interpreted horizons were initially flat and continuous. The individual values for percent shortening are not consistent across the margin but distributed into two zones each with progressively increasing strain in the landward direction. Zone 2 (landward) begins with a percent shortening for S8 at 22% and linearly decreases to 2% shortening as you move seaward to S4. The Zone 1-2 boundary is marked by a slope break coinciding with an increase in percent shortening (S3,15%) followed by less shortening seaward (9%, 8%). Shortening and the associated strain is focused at the landward side of the two zones, within S3 and S8. We conclude that the Costa Rican margin has some degree of mechanical partitioning, with a notable discontinuity in strain patterns occurring 10 km from the trench.

Transient Stability Output Margin Estimation Based on Energy Function Method

NASA Astrophysics Data System (ADS)

Miwa, Natsuki; Tanaka, Kazuyuki

In this paper, a new method of estimating critical generation margin (CGM) in power systems is proposed from the viewpoint of transient stability diagnostic. The proposed method has the capability to directly compute the stability limit output for a given contingency based on transient energy function method (TEF). Since CGM can be directly obtained by the limit output using estimated P-θ curves and is easy to understand, it is more useful rather than conventional critical clearing time (CCT) of energy function method. The proposed method can also estimate CGM as its negative value that means unstable in present load profile, then negative CGM can be directly utilized as generator output restriction. The proposed method is verified its accuracy and fast solution ability by applying to simple 3-machine model and IEEJ EAST10-machine standard model. Furthermore the useful application to severity ranking of transient stability for a lot of contingency cases is discussed by using CGM.

17 CFR 242.405 - Withdrawal of margin.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 17 Commodity and Securities Exchanges 3 2010-04-01 2010-04-01 false Withdrawal of margin. 242.405 Section 242.405 Commodity and Securities Exchanges SECURITIES AND EXCHANGE COMMISSION (CONTINUED) REGULATIONS M, SHO, ATS, AC, AND NMS AND CUSTOMER MARGIN REQUIREMENTS FOR SECURITY FUTURES Customer Margin...

Identity Texts and Academic Achievement: Connecting the Dots in Multilingual School Contexts

ERIC Educational Resources Information Center

Cummins, Jim; Hu, Shirley; Markus, Paula; Kristiina Montero, M.

2015-01-01

The construct of "identity text" conjoins notions of identity affirmation and literacy engagement as equally relevant to addressing causes of underachievement among low socioeconomic status, multilingual, and marginalized group students. Despite extensive empirical evidence supporting the impact on academic achievement of both identity…

Mathematics anxiety and mathematics achievement

NASA Astrophysics Data System (ADS)

Sherman, Brian F.; Wither (Post.), David P.

2003-09-01

This paper is a distillation of the major result from the 1998 Ph.D. thesis of the late David Wither. It details a longitudinal study over five years of the relationship between mathematics anxiety and mathematics achievement. It starts from the already well documented negative correlation between the two, and seeks to establish one of the three hypotheses—that mathematics anxiety causes an impairment of mathematics achievement; that lack of mathematics achievement causes mathematics anxiety; or that there is a third underlying cause of the two.

Evolution of Devonian carbonate-shelf margin, Nevada

USGS Publications Warehouse

Morrow, J.R.; Sandberg, C.A.

2008-01-01

The north-trending, 550-km-long Nevada segment of the Devonian carbonate-shelf margin, which fringed western North America, evidences the complex interaction of paleotectonics, eustasy, biotic changes, and bolide impact-related influences. Margin reconstruction is complicated by mid-Paleozoic to Paleogene compressional tectonics and younger extensional and strike-slip faulting. Reports published during the past three decades identify 12 important events that influenced development of shelf-margin settings; in chronological order, these are: (1) Early Devonian inheritance of Silurian stable shelf inargin, (2) formation of Early to early Middle 'Devonian shelf-margin basins, (3) propradation of later Middle Devonian shelf margin, (4) late Middle Devonian Taghanic ondap and continuing long-term Frasnian transgression, (5) initiation of latest Middle Devonian to early Frasnian proto-Antler orogenic forebulge, (6) mid-Frasnian Alamo Impact, (7) accelerated development of proto-Antler forebulge and backbulge Pilot basin, (8) global late Frasnian sentichatovae sea-level rise, (9) end-Frasnian sea-level fluctuations and ensuing mass extinction, (10) long-term Famennian regression and continept-wide erosion, (11) late Famennian emergence: of Ahtler orogenic highlands, and (12) end-Devonian eustatic sea-level fall. Although of considerable value for understanding facies relationships and geometries, existing standard carbonate platform-margin models developed for passive settings else-where do not adequately describe the diverse depositional and, structural settings along the Nevada Devonian platform margin. Recent structural and geochemical studies suggest that the Early to Middle Devonian-shelf-margin basins may have been fault-bound and controlled by inherited Precambrian structure. Subsequently, the migrating latest Middle to Late Devonian Antler orogenic forebulge exerted a dominant control on shelf-margin position, morphology, and sedimentation. ??Geological Society of

17 CFR 41.45 - Required margin.

Code of Federal Regulations, 2010 CFR

2010-04-01

...) Offsetting positions. Notwithstanding the margin levels specified in paragraph (b)(1) of this section, a self-regulatory authority may set the required initial or maintenance margin level for an offsetting position...

Paying a Premium: How Patient Complexity Affects Costs and Profit Margins

PubMed Central

Taheri, Paul A.; Butz, David A.; Greenfield, Lazar J.

1999-01-01

Objective and Background Tertiary medical centers continue to be under extreme pressure to deliver high-complexity care, but paradoxically there is considerable pressure within these institutions to reduce their emphasis on tertiary care and refocus their efforts to develop a more community-like practice. The genesis of this pressure is the perceived profitability of routine surgical activity when compared with more complex care. The purpose of this study is to assess how the total cost and profit (loss) margin can vary for an entire trauma service. The authors also evaluate payments for specific trauma-related diagnostic-related groups (DRGs) and analyze how hospital margins were affected based on mortality outcome. Materials and Methods The authors analyzed the actual cost of all trauma discharges (n = 692) at their level I trauma center for fiscal year 1997. Data were obtained from the trauma registry and the hospital cost accounting system. Total cost was defined as the sum of the variable, fixed, and indirect costs associated with each patient. Margin was defined as expected payments minus total cost. The entire population and all DRGs with 10 or more patients were stratified based on survival outcome, Injury Severity Score, insurance status, and length of stay. The mean total costs for survivors and nonsurvivors within these various categories and their margins were evaluated. Results The profit margin on nonsurvivors was $5898 greater than for survivors, even though the mean total cost for nonsurvivors was $28,821 greater. Within the fixed fee arrangement, approximately 44% of transfers had a negative margin. Both survivors and nonsurvivors become increasingly profitable out to 20 days and subsequently become unprofitable beyond 21 days, but nonsurvivors were more profitable than survivors. Conclusions There is a wide variance in both the costs and margins within trauma-related DRGs. The DRG payment system disproportionately reimburses providers for

Sci—Thur PM: Planning and Delivery — 04: Respiratory margin derivation and verification in partial breast irradiation

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

Quirk, S; Conroy, L; Smith, WL

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 (2–20more » 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.« less

Flow and Performance Calculations of Axial Compressor near Stall Margin

NASA Astrophysics Data System (ADS)

Hwang, Yoojun; Kang, Shin-Hyoung

2010-06-01

Three-dimensional flows through a Low Speed Research Axial Compressor were numerically conducted in order to estimate the performance through unsteady and steady-state simulations. The first stage with the inlet guide vane was investigated at the design point to confirm that the rotor blade induced periodicity exists. Special attention was paid to the flow near the stall condition to inspect the flow behavior in the vicinity of the stall margin. The performance predicted under the steady-state assumption is in good agreement with the measured data. However, the steady-state calculations induce more blockage through the blade passage. Flow separations on the blade surface and end-walls are reduced when unsteady simulation is conducted. The negative jet due to the wake of the rotor blade periodically distorts the boundary layer on the surface of the stator blade and improves the performance of the compressor in terms of the pressure rise. The advantage of the unsteadiness increases as the flow rate reduces. In addition, the rotor tip leakage flow is forced downstream by the unsteadiness. Consequently, the behavior contributes to extending the range of operation by preventing the leakage flow from proceeding upstream near the stall margin.

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…

The Continental Margins Program in Georgia

USGS Publications Warehouse

Cocker, M.D.; Shapiro, E.A.

1999-01-01

From 1984 to 1993, the Georgia Geologic Survey (GGS) participated in the Minerals Management Service-funded Continental Margins Program. Geological and geophysical data acquisition focused on offshore stratigraphic framework studies, phosphate-bearing Miocene-age strata, distribution of heavy minerals, near-surface alternative sources of groundwater, and development of a PC-based Coastal Geographic Information System (GIS). Seven GGS publications document results of those investigations. In addition to those publications, direct benefits of the GGS's participation include an impetus to the GGS's investigations of economic minerals on the Georgia coast, establishment of a GIS that includes computer hardware and software, and seeds for additional investigations through the information and training acquired as a result of the Continental Margins Program. These addtional investigations are quite varied in scope, and many were made possible because of GIS expertise gained as a result of the Continental Margins Program. Future investigations will also reap the benefits of the Continental Margins Program.From 1984 to 1993, the Georgia Geologic Survey (GGS) participated in the Minerals Management Service-funded Continental Margins Program. Geological and geophysical data acquisition focused on offshore stratigraphic framework studies, phosphate-bearing Miocene-age strata, distribution of heavy minerals, near-surface alternative sources of groundwater, and development of a PC-based Coastal Geographic Information System (GIS). Seven GGS publications document results of those investigations. In addition to those publications, direct benefits of the GGS's participation include an impetus to the GGS's investigations of economic minerals on the Georgia coast, establishment of a GIS that includes computer hardware and software, and seeds for additional investigations through the information and training acquired as a result of the Continental Margins Program. These additional

Is Alcohol Consumption Associated with Poor Academic Achievement in University Students?

PubMed Central

El Ansari, Walid; Stock, Christiane; Mills, Claire

2013-01-01

Background: We assessed associations between educational achievement and alcohol consumption. Methods: We employed five alcohol consumption measures (length of time of and amount consumed during most recent drinking occasion, frequency of alcohol consumption, heavy episodic drinking, problem drinking); and three educational achievement indicators (students’ subjective importance of achieving good grades, students’ appraisal of their academic performance in comparison with peers, students’ actual module mark). Results: Males were positively associated with all five alcohol consumption measures. Age was negatively associated with three alcohol consumption measures. While students´ importance of good grades was negatively associated with three alcohol consumption measures, academic performance in comparison with peers was negatively associated with heavy episodic drinking. Actual module mark was not associated with any alcohol consumption measure. Conclusions: Alcohol consumption showed negative associations with motivation for and subjectively achieved academic performance. University alcohol prevention activities might have positive impact on students’ academic success. PMID:24319558

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

Biofuel development, food security and the use of marginal land in China.

PubMed

Qiu, Huanguang; Huang, Jikun; Keyzer, Michiel; van Veen, Wim; Rozelle, Scott; Fisher, Guenther; Ermolieva, Tatiana

2011-01-01

With concerns of energy shortages, China, like the United States, European Union, and other countries, is promoting the development of biofuels. However, China also faces high future demand for food and feed, and so its bioenergy program must try to strike a balance between food and fuel. The goals of this paper are to provide an overview of China's current bioethanol program, identify the potential for using marginal lands for feedstock production, and measure the likely impacts of China's bioethanol development on the nation's future food self-sufficiency. Our results indicate that the potential to use marginal land for bioethanol feedstock production is limited. Applying a modeling approach based on highly disaggregated data by region, our analysis shows that the target of 10 million t of bioethanol by 2020 seems to be a prudent target, causing no major disturbances in China's food security. But the expansion of bioethanol may increase environmental pressures due to the higher levels of fertilizer use. This study shows also that if China were able to cultivate 45% of its required bioethanol feedstock on new marginal land, it would further limit negative effects of the bioethanol program on the domestic and international economy, but at the expense of having to apply another 750 thousand t of fertilizer. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

Results of Upfront Therapy for Marginal Zone Lymphoma.

PubMed

Ortega, José L; Cabanillas, Fernando; Rivera, Noridza; Tirado-Gomez, Maribel; Hallman, Deana; Pardo, Wandaly I; Bruno, Margarita

2017-12-01

Marginal zone lymphomas (MZLs) are indolent disorders composed of 3 subtypes: extranodal marginal zone lymphoma (MALT), splenic marginal zone lymphoma (SMZL), and nodal marginal zone lymphoma (NMZL). Early-stage MALT is treated with radiotherapy or antibiotics, and advanced MALT and NMZL are managed with either watch and wait or chemotherapy. SMZLs are treated with splenectomy or rituximab. However, because these approaches have failed to cure patients with SMZL and NMZL, we have systematically used upfront chemotherapy for them, as well as for advanced MALT. We report the outcomes of this approach. A total of 44 patients with MZL were identified from our database and divided into 2 groups. Group 1 (22 with early-stage MALT) patients received either radiotherapy (n = 17) or antibiotics with or without surgery (n = 5). Group 2 included 9 patients with advanced MALT, 9 with SMZL, and 4 with NMZL. Group 2 was treated with FND-R (fludarabine 25 mg/m 2 on days 1 to 3, mitoxantrone 10 mg/m 2 on day 1, dexamethasone 20 mg on days 1 to 5, and rituximab 375 mg/m 2 on day 1; n = 14) or CHOP-R (cyclophosphamide 750 mg/m 2 on day 1, doxorubicin 50 mg/m 2 on day 1, vincristine 2 mg intravenous push on day 1, prednisone 100 mg/m 2 orally on days 1 to 5, rituximab 375 mg/m 2 on day 1; n = 8), followed by maintenance rituximab for 70%. All patients achieved complete remission, and only 2 patients in group 1 had developed a relapse at 70 and 75 months. Both relapses were stage I MALT that had initially been treated with radiotherapy. Both were salvaged with FND-R and remained free of disease at 27 and 39 months after the relapse. At 10 years, the failure-free survival for the 44 patients was 80% and the overall survival was 100%. None of the patients in group 2 developed a relapse. The long-term toxicities have been acceptable. The excellent responses using upfront chemotherapy for MZL suggests that this disorder is curable. Our results should be confirmed in a prospective trial

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

Max-margin weight learning for medical knowledge network.

PubMed

Jiang, Jingchi; Xie, Jing; Zhao, Chao; Su, Jia; Guan, Yi; Yu, Qiubin

2018-03-01

The application of medical knowledge strongly affects the performance of intelligent diagnosis, and method of learning the weights of medical knowledge plays a substantial role in probabilistic graphical models (PGMs). The purpose of this study is to investigate a discriminative weight-learning method based on a medical knowledge network (MKN). We propose a training model called the maximum margin medical knowledge network (M 3 KN), which is strictly derived for calculating the weight of medical knowledge. Using the definition of a reasonable margin, the weight learning can be transformed into a margin optimization problem. To solve the optimization problem, we adopt a sequential minimal optimization (SMO) algorithm and the clique property of a Markov network. Ultimately, M 3 KN not only incorporates the inference ability of PGMs but also deals with high-dimensional logic knowledge. The experimental results indicate that M 3 KN obtains a higher F-measure score than the maximum likelihood learning algorithm of MKN for both Chinese Electronic Medical Records (CEMRs) and Blood Examination Records (BERs). Furthermore, the proposed approach is obviously superior to some classical machine learning algorithms for medical diagnosis. To adequately manifest the importance of domain knowledge, we numerically verify that the diagnostic accuracy of M 3 KN is gradually improved as the number of learned CEMRs increase, which contain important medical knowledge. Our experimental results show that the proposed method performs reliably for learning the weights of medical knowledge. M 3 KN outperforms other existing methods by achieving an F-measure of 0.731 for CEMRs and 0.4538 for BERs. This further illustrates that M 3 KN can facilitate the investigations of intelligent healthcare. Copyright © 2018 Elsevier B.V. All rights reserved.

A quantitative analysis of transtensional margin width

NASA Astrophysics Data System (ADS)

Jeanniot, Ludovic; Buiter, Susanne J. H.

2018-06-01

Continental rifted margins show variations between a few hundred to almost a thousand kilometres in their conjugated widths from the relatively undisturbed continent to the oceanic crust. Analogue and numerical modelling results suggest that the conjugated width of rifted margins may have a relationship to their obliquity of divergence, with narrower margins occurring for higher obliquity. We here test this prediction by analysing the obliquity and rift width for 26 segments of transtensional conjugate rifted margins in the Atlantic and Indian Oceans. We use the plate reconstruction software GPlates (http://www.gplates.org) for different plate rotation models to estimate the direction and magnitude of rifting from the initial phases of continental rifting until breakup. Our rift width corresponds to the distance between the onshore maximum topography and the last identified continental crust. We find a weak positive correlation between the obliquity of rifting and rift width. Highly oblique margins are narrower than orthogonal margins, as expected from analogue and numerical models. We find no relationships between rift obliquities and rift duration nor the presence or absence of Large Igneous Provinces (LIPs).

Analysis of surgical margins in oral cancer using in situ fluorescence spectroscopy.

PubMed

Francisco, Ana Lucia Noronha; Correr, Wagner Rafael; Pinto, Clóvis Antônio Lopes; Gonçalves Filho, João; Chulam, Thiago Celestino; Kurachi, Cristina; Kowalski, Luiz Paulo

2014-06-01

Oral cancer is a public health problem with high prevalence in the population. Local tumor control is best achieved by complete surgical resection with adequate margins. A disease-free surgical margin correlates with a lower rate of local recurrence and a higher rate of disease-free survival. Fluorescence spectroscopy is a noninvasive diagnostic tool that can aid in real-time cancer detection. The technique, which evaluates the biochemical composition and structure of tissue fluorescence, is relatively simple, fast and, accurate. This study aimed to compare oral squamous cell carcinoma lesions to surgical margins and the mucosa of healthy volunteers by fluorescence spectroscopy. The sample consisted of 56 individuals, 28 with oral squamous cell carcinoma and 28 healthy volunteers with normal oral mucosa. Thirty six cases (64.3%) were male and the mean age was 60.9 years old. The spectra were classified and compared to histopathology to determine fluorescence efficiency for diagnostic discrimination of tumors. In the analysis of the other cases we observed discrimination between normal mucosa, injury and margins. At two-year follow up, three individuals had local recurrence, and in two cases investigation fluorescence in the corresponding area showed qualitative differences in spectra between the recurrence area and the area without recurrence at the same anatomical site in the same patient. In situ analysis of oral mucosa showed the potential of fluorescence spectroscopy as a diagnostic tool that can aid in discrimination of altered mucosa and normal mucosa. Copyright © 2014 Elsevier Ltd. All rights reserved.

Negative refraction using Raman transitions and chirality

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

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.

Marginality principle

USDA-ARS?s Scientific Manuscript database

Soil is a fragile resource supplying many goods and services. Given the diversity of soil across the world and within a landscape, there are many different capacities among soils to provide the basic soil functions. Marginality of soils is a difficult process to define because the metrics to define ...

The Effects of a Teacher In-Service on Low-Achieving Grade 7 and 8 Mathematics Students

ERIC Educational Resources Information Center

Ross, John A.; Xu, YunMei; Ford, John

2008-01-01

Previous research (e.g., Woodward & Baxter, 1997) found that Standards-based mathematics teaching provides marginal or no benefits for low achievers, in contrast with positive effects for middle and high ability students. A randomized quasi-experiment in 52 Canadian schools found that low achieving grade 7 and 8 students who received support…

DVH- and NTCP-based dosimetric comparison of different longitudinal margins for VMAT-IMRT of esophageal cancer.

PubMed

Münch, S; Oechsner, M; Combs, S E; Habermehl, D

2017-08-15

To cover the microscopic tumor spread in squamous cell carcinoma of the esophagus (SCC), longitudinal margins of 3-4 cm are used for radiotherapy (RT) protocols. However, smaller margins of 2-3 cm might be reasonable when advanced diagnostic imaging is integrated into target volume delineation. Purpose of this study was to compare the dose distribution and deposition to the organs at risk (OAR) for different longitudinal margins using a DVH- and NTCP-based approach. Ten patients with SCC of the middle or lower third were retrospectively selected. Three planning target volumes (PTV) with longitudinal margins of 4 cm, 3 cm and 2 cm and an axial margin of 1.5 cm to the gross target volume (GTV) were defined for each patient. For each PTV two treatment plans with total doses of 41.4 Gy (neoadjuvant treatment) and 50.4 Gy (definite treatment) were calculated. Dose to the lungs, heart, myelon and liver were then evaluated and compared between different PTVs. When using a longitudinal margin of 3 cm instead of 4 cm, all dose parameters (Dmin, Dmean, Dmedian and V5-V35), except Dmax could be significantly reduced for the lungs. Regarding the heart, a significant reduction was seen for Dmean and V5, but not for Dmin, Dmax, Dmedian and V10-V35. When comparing a longitudinal margin of 4 cm to a longitudinal margin of 2 cm, a significant difference was calculated for Dmin, Dmean, Dmedian and V5-V35 of the lungs and for Dmax, Dmean and V5-V35 of the heart. Nevertheless, no difference was seen for median heart dose. An additional dose reduction for V10 of the heart was achieved for definite treatment plans when using a longitudinal margin of 3 cm. The NTCP-based risk of pneumonitis was significantly reduced by a margin reduction to 2 cm for neoadjuvant and definite treatment plans. Reduction of longitudinal margins from 4 cm to 3 cm can significantly reduce the dose to lungs and Dmean of the heart. Despite clinical benefit and oncologic outcome remain unclear

Methylation patterns in marginal zone lymphoma.

PubMed

Arribas, Alberto J; Bertoni, Francesco

Promoter DNA methylation is a major regulator of gene expression and transcription. The identification of methylation changes is important for understanding disease pathogenesis, for identifying prognostic markers and can drive novel therapeutic approaches. In this review we summarize the current knowledge regarding DNA methylation in MALT lymphoma, splenic marginal zone lymphoma, nodal marginal zone lymphoma. Despite important differences in the study design for different publications and the existence of a sole large and genome-wide methylation study for splenic marginal zone lymphoma, it is clear that DNA methylation plays an important role in marginal zone lymphomas, in which it contributes to the inactivation of tumor suppressors but also to the expression of genes sustaining tumor cell survival and proliferation. Existing preclinical data provide the rationale to target the methylation machinery in these disorders. Copyright © 2016 Elsevier Ltd. All rights reserved.

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…

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…

Continental transform margins : state of art and future milestones

NASA Astrophysics Data System (ADS)

Basile, Christophe

2010-05-01

Transform faults were defined 45 years ago as ‘a new class of fault' (Wilson, 1965), and transform margins were consequently individualized as a new class of continental margins. While transform margins represent 20 to 25 % of the total length of continent-ocean transitions, they were poorly studied, especially when compared with the amount of data, interpretations, models and conceptual progress accumulated on divergent or convergent continental margins. The best studied examples of transform margins are located in the northern part of Norway, south of South Africa, in the gulf of California and on both sides of the Equatorial Atlantic. Here is located the Côte d'Ivoire - Ghana margin, where the more complete data set was acquired, based on numerous geological and geophysical cruises, including ODP Leg 159. The first models that encompassed the structure and evolution of transform margins were mainly driven by plate kinematic reconstructions, and evidenced the diachronic end of tectonic activity and the non-cylindrical character of these margins, with a decreasing strike-slip deformation from the convex to the concave divergent-transform intersections. Further thermo-mechanical models were more specifically designed to explain the vertical displacements along transform margins, and especially the occurrence of high-standing marginal ridges. These thermo-mechanical models involved either heat transfer from oceanic to continental lithospheres across the transform faults or tectonically- or gravity-driven mass transfer in the upper crust. These models were far from fully fit observations, and were frequently dedicated to specific example, and not easily generalizable. Future work on transform continental margins may be expected to fill some scientific gaps, and the definition of working directions can benefit from the studies dedicated to other types of margins. At regional scale the structural and sedimentological variability of transform continental margins has

Comparative Associations Between Achieved Bicultural Identity, Achieved Ego Identity, and Achieved Religious Identity and Adaptation Among Australian Adolescent Muslims.

PubMed

Abu-Rayya, Hisham M; Abu-Rayya, Maram H; White, Fiona A; Walker, Richard

2018-04-01

This study examined the comparative roles of biculturalism, ego identity, and religious identity in the adaptation of Australian adolescent Muslims. A total of 504 high school Muslim students studying at high schools in metropolitan Sydney and Melbourne, Australia, took part in this study which required them to complete a self-report questionnaire. Analyses indicated that adolescent Muslims' achieved religious identity seems to play a more important role in shaping their psychological and socio-cultural adaptation compared to adolescents' achieved bicultural identity. Adolescents' achieved ego identity tended also to play a greater role in their psychological and socio-cultural adaptation than achieved bicultural identity. The relationships between the three identities and negative indicators of psychological adaptation were consistently indifferent. Based on these findings, we propose that the three identity-based forces-bicultural identity development, religious identity attainment, and ego identity formation-be amalgamated into one framework in order for researchers to more accurately examine the adaptation of Australian adolescent Muslims.

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…

Radiotherapy boost dose-escalation for invasive breast cancer after breast-conserving surgery: 2093 patients treated with a prospective margin-directed policy.

PubMed

Livi, Lorenzo; Meattini, Icro; Franceschini, Davide; Saieva, Calogero; Meacci, Fiammetta; Marrazzo, Livia; Gerlain, Elena; Desideri, Isacco; Scotti, Vieri; Nori, Jacopo; Sanchez, Luis Jose; Orzalesi, Lorenzo; Bonomo, Pierluigi; Greto, Daniela; Bianchi, Simonetta; Biti, Giampaolo

2013-08-01

To investigate the outcome of invasive early breast cancer patients that underwent breast-conserving surgery and adjuvant radiotherapy (RT), treated with a prospective margin-directed institutional policy for RT boost dose, based on final margins status (FMS). A total of 2093 patients were treated between 2000 and 2008. 10 Gy boost was prescribed in case of FMS>5mm; 16 Gy boost with FMS between 2 and 5mm; 20 Gy boost in case of FMS<2mm or positive. After a median follow up of 5.2 years, we recorded 41 local relapse (LR, 2%). Concerning LR free survival, age at diagnosis, nuclear grade, hormonal status, T-stage, adjuvant hormonal therapy and adjuvant chemotherapy emerged as significant parameters (p-values from log rank test <0.05). FMS, that directed the RT boost dose, did not have significant impact on LRFS (p=0.46). LR rates were 2.3% for FMS<2mm, 2.6% for 2-5mm FMS and 1.8% for FMS>5mm. At multivariate analysis, higher nuclear grade (p=0.045), triple negative subtype (p=0.036) and higher T-stage (p=0.02) resulted as the independent predictors of LR occurrence. Our experience showed that a margin-directed policy of RT boost dose-escalation seems to reduce the negative impact of FMS on LR, but it is not able to overcome the unfavorable effect of higher nuclear grade, higher T stage and triple negative subtype. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

US refining margin trend: austerity continues

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

Not Available

Should crude oil prices hold near current levels in 1988, US refining margins might improve little, if at all. If crude oil prices rise, margins could blush pink or worse. If they drop, US refiners would still probably not see much margin improvement. In fact, if crude prices fall, they could set off another free fall in products markets and threaten refiner survival. Volatility in refined products markets and low product demand growth are the underlying reasons for caution or pessimism as the new year approaches. Recent directional patterns in refining margins are scrutinized in this issue. This issue alsomore » contains the following: (1) the ED refining netback data for the US Gulf and West Coasts, Rotterdam, and Singapore for late November, 1987; and (2) the ED fuel price/tax series for countries of the Eastern Hemisphere, November, 1987 edition. 4 figures, 6 tables.« less

Updated evidence-based clinical practice guidelines for the diagnosis and management of melanoma: definitive excision margins for primary cutaneous melanoma.

PubMed

Sladden, Michael J; Nieweg, Omgo E; Howle, Julie; Coventry, Brendon J; Thompson, John F

2018-02-19

Definitive management of primary cutaneous melanoma consists of surgical excision of the melanoma with the aim of curing the patient. The melanoma is widely excised together with a safety margin of surrounding skin and subcutaneous tissue, after the diagnosis and Breslow thickness have been established by histological assessment of the initial excision biopsy specimen. Sentinel lymph node biopsy should be discussed for melanomas ≥ 1 mm thickness (≥ 0.8 mm if other high risk features) in which case lymphoscintigraphy must be performed before wider excision of the primary melanoma site. The 2008 evidence-based clinical practice guidelines for the management of melanoma (http://www.cancer.org.au/content/pdf/HealthProfessionals/ClinicalGuidelines/ClinicalPracticeGuidelines-ManagementofMelanoma.pdf) are currently being revised and updated in a staged process by a multidisciplinary working party established by Cancer Council Australia. The guidelines for definitive excision margins for primary melanomas have been revised as part of this process. Main recommendations: The recommendations for definitive wide local excision of primary cutaneous melanoma are: melanoma in situ: 5-10 mm margins invasive melanoma (pT1) ≤ 1.0 mm thick: 1 cm margins invasive melanoma (pT2) 1.01-2.00 mm thick: 1-2 cm margins invasive melanoma (pT3) 2.01-4.00 mm thick: 1-2 cm margins invasive melanoma (pT4) > 4.0 mm thick: 2 cm margins Changes in management as a result of the guideline: Based on currently available evidence, excision margins for invasive melanoma have been left unchanged compared with the 2008 guidelines. However, melanoma in situ should be excised with 5-10 mm margins, with the aim of achieving complete histological clearance. Minimum clearances from all margins should be assessed and stated. Consideration should be given to further excision if necessary; positive or close histological margins are unacceptable.

Sparse non-negative matrix factorizations via alternating non-negativity-constrained least squares for microarray data analysis.

PubMed

Kim, Hyunsoo; Park, Haesun

2007-06-15

Many practical pattern recognition problems require non-negativity constraints. For example, pixels in digital images and chemical concentrations in bioinformatics are non-negative. Sparse non-negative matrix factorizations (NMFs) are useful when the degree of sparseness in the non-negative basis matrix or the non-negative coefficient matrix in an NMF needs to be controlled in approximating high-dimensional data in a lower dimensional space. In this article, we introduce a novel formulation of sparse NMF and show how the new formulation leads to a convergent sparse NMF algorithm via alternating non-negativity-constrained least squares. We apply our sparse NMF algorithm to cancer-class discovery and gene expression data analysis and offer biological analysis of the results obtained. Our experimental results illustrate that the proposed sparse NMF algorithm often achieves better clustering performance with shorter computing time compared to other existing NMF algorithms. The software is available as supplementary material.

Increasing Educational Achievement via Self Concept Change.

ERIC Educational Resources Information Center

Scheirer, Mary Ann; Kraut, Robert E.

1979-01-01

Literature linking self-concept and achievement, and evaluation research on educational programs to improve self-concept are analyzed in terms of several self-concept theories. Evidence for a causal connection between self-concept and achievement is negative. Researchers have failed to explore other theoretical approaches to educational change.…

Mandibular marginal contouring in oriental aesthetic surgery: refined surgical concept and operative procedure.

PubMed

Satoh, Kaneshige; Mitsukawa, Nobuyuki

2014-05-01

In aesthetic mandibular contouring surgery, which is often conducted in Asians, the operative procedure is thought to deliver a more aesthetic mandibular shape by means of contouring conducted as a whole from the ramus to the symphysis. The authors describe the refined concept and operative procedures of mandibular marginal contouring. For the 7-year period from 2004 to 2011, mandibular marginal contouring has been used in 57 consecutive series of Japanese subjects. Patient ages ranged from 18 to 33 years, and the subjects included 15 men and 42 women. The surgery was carried out by cutting off the protruding deformed mandibular margin from the ramus to the symphysis. In 53 of 57 cases, the focus was on angle contouring. Concomitant genioplasty by horizontal osteotomy of the chin was conducted in 42 of 57 cases (recession, advancement, shortening, elongation, and correction of the shift variously). In 22 materials exhibiting bulk around the mandibular, the ramus to the body was excised sagittally and thinned. In all the patients, mandibular marginal contouring from the ramus to the symphysis was completed. Partial masseter muscle resection was conducted in 11 of 57 cases. Mandibular contouring effectively achieved a highly satisfactory result in all cases. The upper portion of the peripheral branch of the trunk of the mental nerve was dissected by an electric scalpel in 1 case but sutured immediately using an 8-0 nylon stitch. Transient palsy of the mental nerve was noticed in a few cases but subsided in 1 to 2 months. No particular complications were encountered. No secondary revision was required in this series. In mandibular angle plasty, mandibular marginal contouring from the ramus to the symphysis should be carried out by cutting off the angle keeping in mind the entire mandibular shape. This concept and the procedure can deliver greater patient satisfaction.

Margin estimation and disturbances of irradiation field in layer-stacking carbon-ion beams for respiratory moving targets.

PubMed

Tajiri, Shinya; Tashiro, Mutsumi; Mizukami, Tomohiro; Tsukishima, Chihiro; Torikoshi, Masami; Kanai, Tatsuaki

2017-11-01

Carbon-ion therapy by layer-stacking irradiation for static targets has been practised in clinical treatments. In order to apply this technique to a moving target, disturbances of carbon-ion dose distributions due to respiratory motion have been studied based on the measurement using a respiratory motion phantom, and the margin estimation given by the square root of the summation Internal margin2+Setup margin2 has been assessed. We assessed the volume in which the variation in the ratio of the dose for a target moving due to respiration relative to the dose for a static target was within 5%. The margins were insufficient for use with layer-stacking irradiation of a moving target, and an additional margin was required. The lateral movement of a target converts to the range variation, as the thickness of the range compensator changes with the movement of the target. Although the additional margin changes according to the shape of the ridge filter, dose uniformity of 5% can be achieved for a spherical target 93 mm in diameter when the upward range variation is limited to 5 mm and the additional margin of 2.5 mm is applied in case of our ridge filter. Dose uniformity in a clinical target largely depends on the shape of the mini-peak as well as on the bolus shape. We have shown the relationship between range variation and dose uniformity. In actual therapy, the upper limit of target movement should be considered by assessing the bolus shape. © The Author 2017. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.

Toward real-time tumor margin identification in image-guided robotic brain tumor resection

NASA Astrophysics Data System (ADS)

Hu, Danying; Jiang, Yang; Belykh, Evgenii; Gong, Yuanzheng; Preul, Mark C.; Hannaford, Blake; Seibel, Eric J.

2017-03-01

For patients with malignant brain tumors (glioblastomas), a safe maximal resection of tumor is critical for an increased survival rate. However, complete resection of the cancer is hard to achieve due to the invasive nature of these tumors, where the margins of the tumors become blurred from frank tumor to more normal brain tissue, but in which single cells or clusters of malignant cells may have invaded. Recent developments in fluorescence imaging techniques have shown great potential for improved surgical outcomes by providing surgeons intraoperative contrast-enhanced visual information of tumor in neurosurgery. The current near-infrared (NIR) fluorophores, such as indocyanine green (ICG), cyanine5.5 (Cy5.5), 5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX (PpIX), are showing clinical potential to be useful in targeting and guiding resections of such tumors. Real-time tumor margin identification in NIR imaging could be helpful to both surgeons and patients by reducing the operation time and space required by other imaging modalities such as intraoperative MRI, and has the potential to integrate with robotically assisted surgery. In this paper, a segmentation method based on the Chan-Vese model was developed for identifying the tumor boundaries in an ex-vivo mouse brain from relatively noisy fluorescence images acquired by a multimodal scanning fiber endoscope (mmSFE). Tumor contours were achieved iteratively by minimizing an energy function formed by a level set function and the segmentation model. Quantitative segmentation metrics based on tumor-to-background (T/B) ratio were evaluated. Results demonstrated feasibility in detecting the brain tumor margins at quasi-real-time and has the potential to yield improved precision brain tumor resection techniques or even robotic interventions in the future.

Marginal Bone Loss Around Early-Loaded SLA and SLActive Implants: Radiological Follow-Up Evaluation Up to 6.5 Years.

PubMed

Şener-Yamaner, Işil Damla; Yamaner, Gökhan; Sertgöz, Atilla; Çanakçi, Cenk Fatih; Özcan, Mutlu

2017-08-01

The aim of this study was to compare marginal bone loss around early-loaded SLA and SLActive tissue-level implants (Straumann Dental Implants; Institut Straumann AG, Basel, Switzerland) after a mean of 81-month follow-up period. One hundred seven SLA and 68 SLActive implants were placed in 55 patients and loaded with final restoration after 8 and 3 weeks of healing time, respectively. Marginal bone loss around implants was determined radiographically at initial and after a mean observation time ranging between 20 and 81 months. The effect of location (mandible vs maxilla), smoking habit, sex, implant length and diameter, and the type of prosthesis on the marginal bone loss was evaluated. The overall cumulative survival rate was 98.2% being 99% for SLA implants and 97% for SLActive implants. After 20-month follow-up period, mean marginal bone loss values for the SLA and SLActive implants were 0.24 and 0.17 mm, respectively. After 81 months, mean marginal bone loss for the SLA and SLActive implants reached 0.71 and 0.53 mm, respectively. Marginal bone loss was affected by the length and type of implant and patients' smoking habit after a mean observation time of 20 months. However, none of the parameters had any significant effect on the marginal bone loss after a follow-up period of 81 months. With both SLA and SLActive implants, successful clinical results could be achieved up to 6.5 years of follow-up period.

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…

Evolved dispersal strategies at range margins

PubMed Central

Dytham, Calvin

2009-01-01

Dispersal is a key component of a species's ecology and will be under different selection pressures in different parts of the range. For example, a long-distance dispersal strategy suitable for continuous habitat at the range core might not be favoured at the margin, where the habitat is sparse. Using a spatially explicit, individual-based, evolutionary simulation model, the dispersal strategies of an organism that has only one dispersal event in its lifetime, such as a plant or sessile animal, are considered. Within the model, removing habitat, increasing habitat turnover, increasing the cost of dispersal, reducing habitat quality or altering vital rates imposes range limits. In most cases, there is a clear change in the dispersal strategies across the range, although increasing death rate towards the margin has little impact on evolved dispersal strategy across the range. Habitat turnover, reduced birth rate and reduced habitat quality all increase evolved dispersal distances at the margin, while increased cost of dispersal and reduced habitat density lead to lower evolved dispersal distances at the margins. As climate change shifts suitable habitat poleward, species ranges will also start to shift, and it will be the dispersal capabilities of marginal populations, rather than core populations, that will influence the rate of range shifting. PMID:19324810

Prognostic significance of positive circumferential resection margin in esophageal cancer: a systematic review and meta-analysis.

PubMed

Wu, Jie; Chen, Qi-Xun; Teng, Li-song; Krasna, Mark J

2014-02-01

To assess the prognostic significance of positive circumferential resection margin on overall survival in patients with esophageal cancer, a systematic review and meta-analysis was performed. Studies were identified from PubMed, EMBASE, and Web of Science. Survival data were extracted from eligible studies to compare overall survival in patients with a positive circumferential resection margin with patients having a negative circumferential resection margin according to the Royal College of Pathologists (RCP) criteria and the College of American Pathologists (CAP) criteria. Survival data were pooled with hazard ratios (HRs) and their corresponding 95% confidence intervals (CIs). A random-effects model meta-analysis on overall survival was performed. The pooled HRs for survival were 1.510 (95% CI, 1.329-1.717; p<0.001) and 2.053 (95% CI, 1.597-2.638; p<0.001) according to the RCP and CAP criteria, respectively. Positive circumferential resection margin was associated with worse survival in patients with T3 stage disease according to the RCP (HR, 1.381; 95% CI, 1.028-1.584; p=0.001) and CAP (HR, 2.457; 95% CI, 1.902-3.175; p<0.001) criteria, respectively. Positive circumferential resection margin was associated with worse survival in patients receiving neoadjuvant therapy according to the RCP (HR, 1.676; 95% CI, 1.023-2.744; p=0.040) and CAP (HR, 1.847; 95% CI, 1.226-2.78; p=0.003) criteria, respectively. Positive circumferential resection margin is associated with poor prognosis in patients with esophageal cancer, particularly in patients with T3 stage disease and patients receiving neoadjuvant therapy. Copyright © 2014 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Characterizing entanglement with global and marginal entropic measures

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

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 statesmore » cannot be discriminated by the majorization criterion.« less

Mental Depreciation and Marginal Decision Making

PubMed

Heath; Fennema

1996-11-01

We propose that individuals practice "mental depreciation," that is, they implicitly spread the fixed costs of their expenses over time or use. Two studies explore how people spread fixed costs on durable goods. A third study shows that depreciation can lead to two distinct errors in marginal decisions: First, people sometimes invest too much effort to get their money's worth from an expense (e.g., they may use a product a lot to spread the fixed expense across more uses). Second, people sometimes invest too little effort to get their money's worth: When people add a portion of the fixed cost to the current costs, their perceived marginal (i.e., incremental) costs exceed their true marginal costs. In response, they may stop investing because their perceived costs surpass the marginal benefits they are receiving. The latter effect is supported by two field studies that explore real board plan decisions by university students.

The Acoustic Signature of Glaciated Margins

NASA Astrophysics Data System (ADS)

Newton, A. M. W.; Huuse, M.

2016-12-01

As climate warms it has become increasingly clear that, in order to fully understand how it might evolve in the future, we need to look for examples of how climate has changed in the past. The Late Cenozoic history of the Arctic Ocean and its surrounding seas has been dominated by glacial-interglacials cycles. This has resulted in major environmental changes in relative sea levels, ice volumes, sea ice conditions, and ocean circulation as marine and terrestrially-based ice sheets waxed and waned. In this work, the acoustic signatures of several glaciated margins in the Northern Hemisphere are investigated and compared. This includes: NW Greenland, West Greenland, East Greenland, mid-Norway, Northern Norway, and the North Sea. These shelf successions preserve a geomorphological record of multiple glaciations and are imaged using seismic reflection data. To date, the majority of work in these areas has tended to focus on the most recent glaciations, which are well known. Here, the focus of the work is to look at the overall stratigraphic setting and how it influences (and is influenced by) the evolution of ice sheets throughout the glacial succession. Landform records are imaged using seismic data to provide a long-term insight into the styles of glaciation on each margin and what relation this may have had on climate, whilst the stratigraphic architectures across each site demonstrate how the inherited geology and tectonic setting can provide a fundamental control on the ice sheet and depositional styles. For example, Scoresby Sund is characterised by significant aggradation that is likely related to subsidence induced by lithospheric cooling rather than rapid glacial deposition, whilst the subsidence of the mid-Norwegian margin can be related to rapid glacial deposition and trapping of sediments behind inversion structures such as the Helland-Hansen Arch. The insights from this multi-margin study allow for regional, basin-wide, glaciological records to be developed

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.

Prediction of margin involvement and local recurrence after skin-sparing and simple mastectomy.

PubMed

Al-Himdani, S; Timbrell, S; Tan, K T; Morris, J; Bundred, N J

2016-07-01

Skin-sparing mastectomy (SSM) facilitates immediate breast reconstruction. We investigated locoregional recurrence rates after SSM compared with simple mastectomy and the factors predicting oncological failure. Patients with early breast cancer that underwent mastectomy between 2000 and 2005 at a single institution were studied to ascertain local and systemic recurrence rates between groups. Kaplan-Meier curves and log-rank test were used to evaluate disease-free survival. Patients (n = 577) underwent simple mastectomy (80%) or SSM (20%). Median follow up was 80 months. Patients undergoing SSM were of younger average age, less often had involved lymph nodes (22% vs 44%, p < 0.001), more often had DCIS present (79% vs 53%, p < 0.001) and involved margins (29% vs 15%, p = 0.001). Involved surgical margins were associated with large size (p = 0.001). The 8-year local recurrence (LR) rates were 7.9% for SSM and 5% for simple mastectomy respectively (p = 0.35). Predictors of locoregional recurrence were lymph node involvement (HR 8.0, for >4 nodes, p < 0.001) and involved surgical margins (HR 3.3, p = 0.002). In node negative patients, SSM was a predictor of locoregional recurrence (HR 4.8 [1.1, 19.9], p = 0.033). Delayed reconstruction is more appropriate for node positive early breast cancer after post-mastectomy radiotherapy. Re-excision of involved margins is essential to prevent local recurrence after mastectomy. Copyright © 2016 Elsevier Ltd, BASO ~ the Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.

Robust and Fragile Mathematical Identities: A Framework for Exploring Racialized Experiences and High Achievement among Black College Students

ERIC Educational Resources Information Center

McGee, Ebony O.

2015-01-01

I introduce the construct of fragile and robust identities for the purpose of exploring the experiences that influenced the mathematical and racial identities of high-achieving Black college students in mathematics and engineering. These students maintained high levels of academic achievement in these fields while enduring marginalization,…

Negative emissions technologies and carbon capture and storage to achieve the Paris Agreement commitments.

PubMed

Haszeldine, R Stuart; Flude, Stephanie; Johnson, Gareth; Scott, Vivian

2018-05-13

How will the global atmosphere and climate be protected? Achieving net-zero CO 2 emissions will require carbon capture and storage (CCS) to reduce current GHG emission rates, and negative emissions technology (NET) to recapture previously emitted greenhouse gases. Delivering NET requires radical cost and regulatory innovation to impact on climate mitigation. Present NET exemplars are few, are at small-scale and not deployable within a decade, with the exception of rock weathering, or direct injection of CO 2 into selected ocean water masses. To keep warming less than 2°C, bioenergy with CCS (BECCS) has been modelled but does not yet exist at industrial scale. CCS already exists in many forms and at low cost. However, CCS has no political drivers to enforce its deployment. We make a new analysis of all global CCS projects and model the build rate out to 2050, deducing this is 100 times too slow. Our projection to 2050 captures just 700 Mt CO 2  yr -1 , not the minimum 6000 Mt CO 2  yr -1 required to meet the 2°C target. Hence new policies are needed to incentivize commercial CCS. A first urgent action for all countries is to commercially assess their CO 2 storage. A second simple action is to assign a Certificate of CO 2 Storage onto producers of fossil carbon, mandating a progressively increasing proportion of CO 2 to be stored. No CCS means no 2°C.This article is part of the theme issue 'The Paris Agreement: understanding the physical and social challenges for a warming world of 1.5°C above pre-industrial levels'. © 2018 The Author(s).

Negative emissions technologies and carbon capture and storage to achieve the Paris Agreement commitments

NASA Astrophysics Data System (ADS)

Haszeldine, R. Stuart; Flude, Stephanie; Johnson, Gareth; Scott, Vivian

2018-05-01

How will the global atmosphere and climate be protected? Achieving net-zero CO2 emissions will require carbon capture and storage (CCS) to reduce current GHG emission rates, and negative emissions technology (NET) to recapture previously emitted greenhouse gases. Delivering NET requires radical cost and regulatory innovation to impact on climate mitigation. Present NET exemplars are few, are at small-scale and not deployable within a decade, with the exception of rock weathering, or direct injection of CO2 into selected ocean water masses. To keep warming less than 2°C, bioenergy with CCS (BECCS) has been modelled but does not yet exist at industrial scale. CCS already exists in many forms and at low cost. However, CCS has no political drivers to enforce its deployment. We make a new analysis of all global CCS projects and model the build rate out to 2050, deducing this is 100 times too slow. Our projection to 2050 captures just 700 Mt CO2 yr-1, not the minimum 6000 Mt CO2 yr-1 required to meet the 2°C target. Hence new policies are needed to incentivize commercial CCS. A first urgent action for all countries is to commercially assess their CO2 storage. A second simple action is to assign a Certificate of CO2 Storage onto producers of fossil carbon, mandating a progressively increasing proportion of CO2 to be stored. No CCS means no 2°C. This article is part of the theme issue `The Paris Agreement: understanding the physical and social challenges for a warming world of 1.5°C above pre-industrial levels'.

Edge Effects along a Seagrass Margin Result in an Increased Grazing Risk on Posidonia australis Transplants.

PubMed

Statton, John; Gustin-Craig, Samuel; Dixon, Kingsley W; Kendrick, Gary A

2015-01-01

A key issue in habitat restoration are the changes in ecological processes that occur when fragments of habitat are lost, resulting in the persistence of habitat-degraded margins. Margins often create or enhance opportunities for negative plant-herbivore interactions, preventing natural or assisted re-establishment of native vegetation into the degraded area. However, at some distance from the habitat margin these negative interactions may relax. Here, we posit that the intensity of species interactions in a fragmented Posidonia australis seagrass meadow may be spatially dependent on proximity to the seagrass habitat edge, whereby the risk of grazing is high and the probability of survival of seagrass transplants is low. To test this, transplants were planted 2 m within the meadow, on the meadow edge at 0m, and at 2m, 10m, 30m, 50m and 100m distance from the edge of the seagrass meadow into the unvegetated sand sheet. There was an enhanced grazing risk 0-10m from the edge, but decreased sharply with increasing distances (>30m). Yet, the risk of grazing was minimal inside the seagrass meadow, indicating that grazers may use the seagrass meadow for refuge but are not actively grazing within it. The relationship between short-term herbivory risk and long-term survival was not straightforward, suggesting that other environmental filters are also affecting survival of P. australis transplants within the study area. We found that daily probability of herbivory was predictable and operating over a small spatial scale at the edge of a large, intact seagrass meadow. These findings highlight the risk from herbivory can be high, and a potential contributing factor to seagrass establishment in restoration programs.

Quantitative measurement of marginal disintegration of ceramic inlays.

PubMed

Hayashi, Mikako; Tsubakimoto, Yuko; Takeshige, Fumio; Ebisu, Shigeyuki

2004-01-01

The objectives of this study include establishing a method for quantitative measurement of marginal change in ceramic inlays and clarifying their marginal disintegration in vivo. An accurate CCD optical laser scanner system was used for morphological measurement of the marginal change of ceramic inlays. The accuracy of the CCD measurement was assessed by comparing it with microscopic measurement. Replicas of 15 premolars restored with Class II ceramic inlays at the time of placement and eight years after restoration were used for morphological measurement by means of the CCD laser scanner system. Occlusal surfaces of the restored teeth were scanned and cross-sections of marginal areas were computed with software. Marginal change was defined as the area enclosed by two profiles obtained by superimposing two cross-sections of the same location at two different times and expressing the maximum depth and mean area of the area enclosed. The accuracy of this method of measurement was 4.3 +/- 3.2 microm in distance and 2.0 +/- 0.6% in area. Quantitative marginal changes for the eight-year period were 10 x 10 microm in depth and 50 x 10(3) microm2 in area at the functional cusp area and 7 x 10 microm in depth and 28 x 10(3) microm2 in area at the non-functional cusp area. Marginal disintegration at the functional cusp area was significantly greater than at the non-functional cusp area (Wilcoxon signed-ranks test, p < 0.05). This study constitutes a quantitative measurement of in vivo deterioration in marginal adaptation of ceramic inlays and indicates that occlusal force may accelerate marginal disintegration.

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.

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.

Personality traits and achievement motives: theoretical and empirical relations between the NEO Personality Inventory-Revised and the Achievement Motives Scale.

PubMed

Diseth, Age; Martinsen, Øyvind

2009-04-01

Theoretical and empirical relations between personality traits and motive dispositions were investigated by comparing scores of 315 undergraduate psychology students on the NEO Personality Inventory-Revised and the Achievement Motives Scale. Analyses showed all NEO Personality Inventory-Revised factors except agreeableness were significantly correlated with the motive for success and the motive to avoid failure. A structural equation model showed that motive for success was predicted by Extraversion, Openness, Conscientiousness, and Neuroticism (negative relation), and motive to avoid failure was predicted by Neuroticism and Openness (negative relation). Although both achievement motives were predicted by several personality factors, motive for success was most strongly predicted by Openness, and motive to avoid failure was most strongly predicted by neuroticism. These findings extended previous research on the relations of personality traits and achievement motives and provided a basis for the discussion of motive dispositions in personality. The results also added to the construct validity of the Achievement Motives Scale.

Gender and Education for All: Progress and Problems in Achieving Gender Equity

ERIC Educational Resources Information Center

Chisamya, Grace; DeJaeghere, Joan; Kendall, Nancy; Khan, Marufa Aziz

2012-01-01

The paper explores the effects of rapid increases in gender parity in primary schooling in Bangladesh and Malawi on gender inequities in schools and communities. Based on an analysis of comparative case studies of marginalized communities, we argue that educational initiatives focused on achieving gender parity provide limited evidence that girls'…

Intercultural Education and Academic Achievement: A Framework for School-Based Policies in Multilingual Schools

ERIC Educational Resources Information Center

Cummins, Jim

2015-01-01

The paper reviews quantitative and qualitative research evidence regarding the relationship between intercultural education and academic achievement among students from socially marginalized communities. Intercultural education is conceptualized as including a focus both on generating understanding and respect for diverse cultural traditions and…

Thrombotic microangiopathy in marginal kidneys after sirolimus use.

PubMed

Pellé, Gaëlle; Xu, Ychen; Khoury, Noujoud; Mougenot, Béatrice; Rondeau, Eric

2005-12-01

The increasing shortage of cadaver donor kidneys has prompted the use of expanded or marginal donor kidneys, ie, from older donors or those with a history of hypertension or diabetes. These marginal kidneys may be especially susceptible to calcineurin inhibitor (CNI)-mediated vasoconstriction and nephrotoxicity. Recipients of renal transplants from marginal donors therefore require non-nephrotoxic immunosuppression. Some investigators have proposed using sirolimus, a novel and potent immunosuppressant, instead of CNIs. Moreover, another complication of solid-organ transplantation is thrombotic microangiopathy (TMA), which affects 3% to 14% of patients on immunosuppression therapy treated with CNIs. Therefore, it was suggested that CNIs may be substituted by sirolimus in patients with posttransplantation CNI-induced TMA. We report 3 patients who received marginal cadaveric kidneys and were administered maintenance immunosuppression with sirolimus, prednisone, and mycophenolate mofetil. They each developed de novo TMA despite never having been previously administered a CNI. In these cases, TMA occurred in marginal kidneys with possible endothelial injury before transplantation. Sirolimus may have prevented recovery from these injuries and thus may have promoted TMA in these marginal kidneys. The risk for such a vascular complication should be kept in mind in patients who receive marginal kidneys and are administered sirolimus, even when sirolimus is used without CNIs.

Overlapping illusions by transformation optics without any negative refraction material.

PubMed

Sun, Fei; He, Sailing

2016-01-11

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.

Reconstructing Rodinia by Fitting Neoproterozoic Continental Margins

USGS Publications Warehouse

Stewart, John H.

2009-01-01

Reconstructions of Phanerozoic tectonic plates can be closely constrained by lithologic correlations across conjugate margins by paleontologic information, by correlation of orogenic belts, by paleomagnetic location of continents, and by ocean floor magmatic stripes. In contrast, Proterozoic reconstructions are hindered by the lack of some of these tools or the lack of their precision. To overcome some of these difficulties, this report focuses on a different method of reconstruction, namely the use of the shape of continents to assemble the supercontinent of Rodinia, much like a jigsaw puzzle. Compared to the vast amount of information available for Phanerozoic systems, such a limited approach for Proterozoic rocks, may seem suspect. However, using the assembly of the southern continents (South America, Africa, India, Arabia, Antarctica, and Australia) as an example, a very tight fit of the continents is apparent and illustrates the power of the jigsaw puzzle method. This report focuses on Neoproterozoic rocks, which are shown on two new detailed geologic maps that constitute the backbone of the study. The report also describes the Neoproterozoic, but younger or older rocks are not discussed or not discussed in detail. The Neoproterozoic continents and continental margins are identified based on the distribution of continental-margin sedimentary and magmatic rocks that define the break-up margins of Rodinia. These Neoproterozoic continental exposures, as well as critical Neo- and Meso-Neoproterozoic tectonic features shown on the two new map compilations, are used to reconstruct the Mesoproterozoic supercontinent of Rodinia. This approach differs from the common approach of using fold belts to define structural features deemed important in the Rodinian reconstruction. Fold belts are difficult to date, and many are significantly younger than the time frame considered here (1,200 to 850 Ma). Identifying Neoproterozoic continental margins, which are primarily

Sensitivity of postplanning target and OAR coverage estimates to dosimetric margin distribution sampling parameters.

PubMed

Xu, Huijun; Gordon, J James; Siebers, Jeffrey V

2011-02-01

accuracy of coverage estimates depends on angular and radial DMD sampling parameters omega or omega eff and delta, as well as the employed sampling technique. Target deltaQ/ < l% and OAR /deltaQ/ < 3% can be achieved with sampling parameters omega or omega eef = 20 degrees, delta =1 mm. Better accuracy (target /deltaQ < 0.5% and OAR /deltaQ < approximately 1%) can be achieved with omega or omega eff = 10 degrees, delta = 0.5 mm. As the number of sampling points decreases, the isotropic sampling method maintains better accuracy than fixed angular sampling. Coverage estimates for post-planning evaluation are essential since coverage values of targets and OARs often differ from the values implied by the static margin-based plans. Finer sampling of the DMD enables more accurate assessment of the effect of geometric uncertainties on coverage estimates prior to treatment. DMD sampling with omega or omega eff = 10 degrees and delta = 0.5 mm should be adequate for planning purposes.

Comparison of Marginal Circumference of Two Different Pre-Crimped Stainless Steel Crowns for Primary Molars After Re-Crimping.

PubMed

Afshar, Hossein; Ghandehari, Mehdi; Soleimani, Banafsheh

2015-12-01

It is not clear what type of pre-crimped crown is more successful in achieving greater marginal adaptation following re-crimping. This study aimed to assess the changes in the circumference of 3M ESPE and MIB pre-crimped stainless steel crowns (SSCs) for the primary maxillary and mandibular first and second molars following re-crimping. This was an in-vitro, experimental study. Initial photographs were obtained from the margins of 3M and MIB SSCs for the upper and lower primary molars using a digital camera. Crown margins were crimped by applying 0.2N force using 114 and 137 pliers. Post-crimping photographs were also obtained and the changes in crown circumference after crimping were calculated using AutoCad software. The percentage of reduction in the circumference of crowns for each tooth was statistically analyzed based on the type of crown using student t-test. The effect of crown design and the associated teeth on the decreased circumference percentage was statistically analyzed by two-sided ANOVA. The percentage of reduction in lower E SSC circumference was 3.71±0.39% in MIB and 6.29±0.62% in 3M crowns. These values were 3.55±0.55% and 7.15±1.13% for the lower Ds, and 3.95±0.43 and 6.24±0.85% for the upper Ds, respectively. For the upper Es, these values were found to be 3.12±0.65% and 5.14±0.94%, respectively. For each tooth, a significant difference was found between MIB and 3M SSCs in terms of the percentage of reduction in crown circumference following crimping. The magnitude of this reduction was smaller in MIB compared to 3M SSCs (P<0.001). Considering the significant reduction in the marginal circumference of precrimped SSCs following re-crimping, it appears that this manipulation must be necessarily performed for MIB and 3M pre-crimped SSCs. By using 3M SSCs, higher marginal adaptation can be achieved following crimping.

Facial expression primes and implicit regulation of negative emotion.

PubMed

Yoon, HeungSik; Kim, Shin Ah; Kim, Sang Hee

2015-06-17

An individual's responses to emotional information are influenced not only by the emotional quality of the information, but also by the context in which the information is presented. We hypothesized that facial expressions of happiness and anger would serve as primes to modulate subjective and neural responses to subsequently presented negative information. To test this hypothesis, we conducted a functional MRI study in which the brains of healthy adults were scanned while they performed an emotion-rating task. During the task, participants viewed a series of negative and neutral photos, one at a time; each photo was presented after a picture showing a face expressing a happy, angry, or neutral emotion. Brain imaging results showed that compared with neutral primes, happy facial primes increased activation during negative emotion in the dorsal anterior cingulated cortex and the right ventrolateral prefrontal cortex, which are typically implicated in conflict detection and implicit emotion control, respectively. Conversely, relative to neutral primes, angry primes activated the right middle temporal gyrus and the left supramarginal gyrus during the experience of negative emotion. Activity in the amygdala in response to negative emotion was marginally reduced after exposure to happy primes compared with angry primes. Relative to neutral primes, angry facial primes increased the subjectively experienced intensity of negative emotion. The current study results suggest that prior exposure to facial expressions of emotions modulates the subsequent experience of negative emotion by implicitly activating the emotion-regulation system.

The Meandering Margin of the Meteorological Moist Tropics

NASA Astrophysics Data System (ADS)

Mapes, Brian E.; Chung, Eui Seok; Hannah, Walter M.; Masunaga, Hirohiko; Wimmers, Anthony J.; Velden, Christopher S.

2018-01-01

Bimodally distributed column water vapor (CWV) indicates a well-defined moist regime in the Tropics, above a margin value near 48 kg m-2 in current climate (about 80% of column saturation). Maps reveal this margin as a meandering, sinuous synoptic contour bounding broad plateaus of the moist regime. Within these plateaus, convective storms of distinctly smaller convective and mesoscales occur sporadically. Satellite data composites across the poleward most margin reveal its sharpness, despite the crude averaging: precipitation doubles within 100 km, marked by both enhancement and deepening of cloudiness. Transported patches and filaments of the moist regime cause consequential precipitation events within and beyond the Tropics. Distinguishing synoptic flows that cross the margin from flows that move the margin is made possible by a novel satellite-based Lagrangian CWV tendency estimate. Climate models do not reliably reproduce the observed bimodal distribution, so studying the moist mode's maintenance processes and the margin-zone air mass transformations, guided by the Lagrangian tendency product, might importantly constrain model moist process treatments.

Continental margin sedimentation: From sediment transport to sequence stratigraphy

USGS Publications Warehouse

Nittrouer, Charles A.; 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

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…

Margins in breast conserving surgery: The financial cost & potential savings associated with the new margin guidelines.

PubMed

Singer, Lauren; Brown, Eric; Lanni, Thomas

2016-08-01

In this study, we compare the indications for re-excision, the findings of additional tumor in the re-excision specimen as they relate to margin status, and costs associated with re-excision based on recent new consensus statements. A retrospective analysis was performed on 462 patients with invasive breast carcinoma who underwent at least one lumpectomy between January 2011 and December 2013. Postoperative data was analyzed based on where additional disease was found, as it relates to the margin status of the initial lumpectomy and the additional direct costs associated with additional procedures. Of the 462 patients sampled, 149 underwent a re-excision surgery (32.2%). Four patients underwent mastectomy as their second operation. In the 40 patients with additional disease found on re-excision, 36 (90.0%) of them had a positive margin on their initial lumpectomy. None of the four mastectomy patients had residual disease. The mean cost of the initial lumpectomy for all 462 patients was $2118.01 plus an additional $1801.92 for those who underwent re-excision. A positive margin was most predictive of finding residual tumor on re-excision as would be expected. Using old criteria only 0.07% (4/61) of patients who had undergone re-excision with a 'clear' margin, had additional tumor found, at a total cost of $106,354.11. Thus, the new consensus guidelines will lead to less overall cost, at no clinical risk to patients while reducing a patient's surgical risk and essentially eliminating delays in adjuvant care. Copyright © 2016 Elsevier Ltd. All rights reserved.

A tunable acoustic metamaterial with double-negativity driven by electromagnets

PubMed Central

Chen, Zhe; Xue, Cheng; Fan, Li; Zhang, Shu-yi; Li, Xiao-juan; Zhang, Hui; Ding, Jin

2016-01-01

With the advance of the research on acoustic metamaterials, the limits of passive metamaterials have been observed, which prompts the studies concerning actively tunable metamaterials with adjustable characteristic frequency bands. In this work, we present a tunable acoustic metamaterial with double-negativity composed of periodical membranes and side holes, in which the double-negativity pass band can be controlled by an external direct-current voltage. The tension and stiffness of the periodically arranged membranes are actively controlled by electromagnets producing additional stresses, and thus, the transmission and phase velocity of the metamaterial can be adjusted by the driving voltage of the electromagnets. It is demonstrated that a tiny direct-current voltage of 6V can arise a shift of double-negativity pass band by 40% bandwidth, which exhibits that it is an easily controlled and highly tunable acoustic metamaterial, and furthermore, the metamaterial marginally causes electromagnetic interference to the surroundings. PMID:27443196

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

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.

[Spatio-temporal distribution of carabids and spiders between semi-natural field margin and the adjacent crop fields in agricultural landscape].

PubMed

Zhang, Xu Zhu; Han, Yin; Yu, Zhen Rong; Liu, Yun Hui

2017-06-18

This study was conducted before and after harvesting of wheat and maize in a typical agricultural landscape of the North China Plain. We investigated the diversity of two important natural enemy groups, carabids and spiders, using pitfall traps at crop field margin with different vegetation structures and their neighboring crop field. Throughout the comparison of the spatial and temporal distribution of the diversity of carabids and spiders in field margin and neighboring field, and the investigation of the relationship between arthropod communities and vegetation structure, this study aimed to understand the role of semi-natural field margin in biodiversity conservation of different natural enemy taxa. Results showed that the abundance of spiders was significantly higher in field margin than in neighboring fields over the entire period. No significant difference of the diversity of carabids in field margin and crop field was observed, but the community composition was different. Number of spider families increased in field margin but deceased in crop field after harvesting, indicating a migration activity between field and field margin. Vegetation structure in the field margin had different association with carabids than with spiders, with diversity of dominant carabid species positively associated with herb coverage and negatively with wood coverage, while the diversity of spider family Linyphiidae was positively associated with herb coverage only. Semi-natural habitat benefited the conservation of the diversity of arthropod natural enemies in crop field via promoting their dispersal to crop field, while such impacts differed from different vegetation structures and varied from target beneficial natural enemy communities. Future studies should focus on in-depth understanding of the food and habitat source requirement of different natural enemy taxa, and hence to design suitable semi-natural habitats to maintain a high diversity of natural enemy communities.

Academic Self-Handicapping and Achievement: A Meta-Analysis

ERIC Educational Resources Information Center

Schwinger, Malte; Wirthwein, Linda; Lemmer, Gunnar; Steinmayr, Ricarda

2014-01-01

Self-handicapping represents a frequently used strategy for regulating the threat to self-esteem elicited by the fear of failing in academic achievement settings. Several studies have documented negative associations between self-handicapping and different educational outcomes, inter alia academic achievement. However, studies on the relation…

Consequences of environmental and biological variances for range margins: a spatially explicit theoretical model

NASA Astrophysics Data System (ADS)

Malanson, G. P.; DeRose, R. J.; Bekker, M. F.

2016-12-01

The consequences of increasing climatic variance while including variability among individuals and populations are explored for range margins of species with a spatially explicit simulation. The model has a single environmental gradient and a single species then extended to two species. Species response to the environment is a Gaussian function with a peak of 1.0 at their peak fitness on the gradient. The variance in the environment is taken from the total variance in the tree ring series of 399 individuals of Pinus edulis in FIA plots in the western USA. The variability is increased by a multiplier of the standard deviation for various doubling times. The variance of individuals in the simulation is drawn from these same series. Inheritance of individual variability is based on the geographic locations of the individuals. The variance for P. edulis is recomputed as time-dependent conditional standard deviations using the GARCH procedure. Establishment and mortality are simulated in a Monte Carlo process with individual variance. Variance for P. edulis does not show a consistent pattern of heteroscedasticity. An obvious result is that increasing variance has deleterious effects on species persistence because extreme events that result in extinctions cannot be balanced by positive anomalies, but even less extreme negative events cannot be balanced by positive anomalies because of biological and spatial constraints. In the two species model the superior competitor is more affected by increasing climatic variance because its response function is steeper at the point of intersection with the other species and so the uncompensated effects of negative anomalies are greater for it. These theoretical results can guide the anticipated need to mitigate the effects of increasing climatic variability on P. edulis range margins. The trailing edge, here subject to increasing drought stress with increasing temperatures, will be more affected by negative anomalies.

Circumferential resection margin (CRM) positivity after MRI assessment and adjuvant treatment in 189 patients undergoing rectal cancer resection.

PubMed

Simpson, G S; Eardley, N; McNicol, F; Healey, P; Hughes, M; Rooney, P S

2014-05-01

The management of rectal cancer relies on accurate MRI staging. Multi-modal treatments can downstage rectal cancer prior to surgery and may have an effect on MRI accuracy. We aim to correlate the findings of MRI staging of rectal cancer with histological analysis, the effect of neoadjuvant therapy on this and the implications of circumferential resection margin (CRM) positivity following neoadjuvant therapy. An analysis of histological data and radiological staging of all cases of rectal cancer in a single centre between 2006 and 2011 were conducted. Two hundred forty-one patients had histologically proved rectal cancer during the study period. One hundred eighty-two patients underwent resection. Median age was 66.6 years, and male to female ratio was 13:5. R1 resection rate was 11.1%. MRI assessments of the circumferential resection margin in patients without neoadjuvant radiotherapy were 93.6 and 88.1% in patients who underwent neoadjuvant radiotherapy. Eighteen patients had predicted positive margins following chemoradiotherapy, of which 38.9% had an involved CRM on histological analysis. MRI assessment of the circumferential resection margin in rectal cancer is associated with high accuracy. Neoadjuvant chemoradiotherapy has a detrimental effect on this accuracy, although accuracy remains high. In the presence of persistently predicted positive margins, complete resection remains achievable but may necessitate a more radical approach to resection.

Sarcopenia Is Negatively Related to High Gravitational Impacts Achieved From Day-to-day Physical Activity.

PubMed

Hartley, April; Gregson, Celia L; Hannam, Kimberly; Deere, Kevin C; Clark, Emma M; Tobias, Jon H

2018-04-17

Sarcopenia has been associated with reduced physical activity (PA). We aimed to determine if sarcopenia, and specific components of muscle size, function, and physical performance, are associated with high impacts achieved during habitual PA, as these are related to bone strength in community-dwelling older women. Participants were older women from the Cohort of Skeletal Health in Bristol and Avon. We defined sarcopenia using the EWGSOP criteria. Lower limb peak muscle power and force were assessed using Jumping Mechanography (JM). High vertical impacts were assessed by tri-axial accelerometry (at least 1.5g above gravity). Cross-sectional associations were analyzed by linear regression, adjusting for age, height and weight (or fat mass for models including appendicular lean mass index), comorbidities, smoking, alcohol, and Index of Multiple Deprivation. Our analyses included 380 participants, with mean age 76.7 (SD 3.0) years; 242 (64%) also completed JM. In age-adjusted analysis, a negative relationship was observed between severity of sarcopenia and high, but not medium or low, impacts (p = .03 for trend). Regarding components of sarcopenia underlying this relationship, multivariable analyses revealed that gait speed (β 1.47 [95% CI 1.14, 1.89], [β-1] reflects the proportionate increase in high impacts per SD increase in exposure) and peak force (1.40 [1.07, 1.84]) were independently associated with high impacts. Older women with sarcopenia experienced fewer bone-strengthening high impacts than those with presarcopenia or without sarcopenia. To increase bone strengthening activity in older women, interventions need to improve both lower limb muscle force and walking speed.

Ultrasound-ultrasound image overlay fusion improves real-time control of radiofrequency ablation margin in the treatment of hepatocellular carcinoma.

PubMed

Minami, Yasunori; Minami, Tomohiro; Hagiwara, Satoru; Ida, Hiroshi; Ueshima, Kazuomi; Nishida, Naoshi; Murakami, Takamichi; Kudo, Masatoshi

2018-05-01

To assess the clinical feasibility of US-US image overlay fusion with evaluation of the ablative margin in radiofrequency ablation (RFA) for hepatocellular carcinoma (HCC). Fifty-three patients with 68 HCCs measuring 0.9-4.0 cm who underwent RFA guided by US-US overlay image fusion were included in this retrospective study. By an overlay of pre-/postoperative US, the tumor image could be projected onto the ablative hyperechoic zone. Therefore, the ablative margin three-dimensionally could be shown during the RFA procedure. US-US image overlay was compared to dynamic CT a few days after RFA for assessment of early treatment response. Accuracy of graded response was calculated, and the performance of US-US image overlay fusion was compared with that of CT using a Kappa agreement test. Technically effective ablation was achieved in a single session, and 59 HCCs (86.8 %) succeeded in obtaining a 5-mm margin on CT. The response with US-US image overlay correctly predicted early CT evaluation with an accuracy of 92.6 % (63/68) (k = 0.67; 95 % CI: 0.39-0.95). US-US image overlay fusion can be proposed as a feasible guidance in RFA with a safety margin and predicts early response of treatment assessment with high accuracy. • US-US image overlay fusion visualizes the ablative margin during RFA procedure. • Visualizing the margin during the procedure can prompt immediate complementary treatment. • US image fusion correlates with the results of early evaluation CT.

Colorado Basin Structure and Rifting, Argentine passive margin

NASA Astrophysics Data System (ADS)

Autin, Julia; Scheck-Wenderoth, Magdalena; Loegering, Markus; Anka, Zahie; Vallejo, Eduardo; Rodriguez, Jorge; Marchal, Denis; Reichert, Christian; di Primio, Rolando

2010-05-01

The Argentine margin presents a strong segmentation with considerable strike-slip movements along the fracture zones. We focus on the volcanic segment (between the Salado and Colorado transfer zones), which is characterized by seaward dipping reflectors (SDR) all along the ocean-continent transition [e.g. Franke et al., 2006; Gladczenko et al., 1997; Hinz et al., 1999]. The segment is structured by E-W trending basins, which differs from the South African margin basins and cannot be explained by classical models of rifting. Thus the study of the relationship between the basins and the Argentine margin itself will allow the understanding of their contemporary development. Moreover the comparison of the conjugate margins suggests a particular evolution of rifting and break-up. We firstly focus on the Colorado Basin, which is thought to be the conjugate of the well studied Orange Basin [Hirsch et al., 2009] at the South African margin [e.g. Franke et al., 2006]. This work presents results of a combined approach using seismic interpretation and structural, isostatic and thermal modelling highlighting the structure of the crust. The seismic interpretation shows two rift-related discordances: one intra syn-rift and the break-up unconformity. The overlying sediments of the sag phase are less deformed (no sedimentary wedges) and accumulated before the generation of oceanic crust. The axis of the Colorado Basin trends E-W in the western part, where the deepest pre-rift series are preserved. In contrast, the basin axis turns to a NW-SE direction in its eastern part, where mainly post-rift sediments accumulated. The most distal part reaches the margin slope and opens into the oceanic basin. The general basin direction is almost orthogonal to the present-day margin trend. The most frequent hypothesis explaining this geometry is that the Colorado Basin is an aborted rift resulting from a previous RRR triple junction [e.g. Franke et al., 2002]. The structural interpretation

Post-resection mucosal margin shrinkage in oral cancer: quantification and significance.

PubMed

Mistry, Rajesh C; Qureshi, Sajid S; Kumaran, C

2005-08-01

The importance of tumor free margins in outcome of cancer surgery is well known. Often the pathological margins are reported to be significantly smaller than the in situ margins. This discrepancy is due to margin shrinkage the quantum of which has not been studied in patients with oral cancers. To quantify the shrinkage of mucosal margin following excision for carcinoma of the oral tongue and buccal mucosa. Mucosal margins were measured prior to resection and half an hour after excision in 27 patients with carcinoma of the tongue and buccal mucosa. The mean margin shrinkage was assessed and the variables affecting the quantum of shrinkage analyzed. The mean shrinkage from the in situ to the post resection margin status was 22.7% (P < 0.0001). The mean shrinkage of the tongue margins was 23.5%, compared to 21.2% for buccal mucosa margins. The mean shrinkage in T1/T2 tumors (25.6%) was significantly more than in T3/T4 (9.2%, P < 0.011). There is significant shrinkage of mucosal margins after surgery. Hence this should be considered and appropriate margins should be taken at initial resection to prevent the agony of post-operative positive surgical margins. Copyright 2005 Wiley-Liss, Inc.

Effect of dual-cure composite resin as restorative material on marginal adaptation of class 2 restorations.

PubMed

Bortolotto, Tissiana; Melian, Karla; Krejci, Ivo

2013-10-01

The present study attempted to find a simple direct adhesive restorative technique for the restoration of Class 2 cavities. A self-etch adhesive system with a dual-cured core buildup composite resin (paste 1 + paste 2) was evaluated in its ability to restore proximo-occlusal cavities with margins located on enamel and dentin. The groups were: A, cavity filling (cf) with paste 1 (light-curing component) by using a layering technique; B, cf by mixing both pastes, bulk insertion, and dual curing; and C, cf by mixing both pastes, bulk insertion, and chemical curing. Two control groups (D, negative, bulk; and E, positive, layering technique) were included by restoring cavities with a classic three-step etch-and-rinse adhesive and a universal restorative composite resin. SEM margin analysis was performed before and after thermomechanical loading in a chewing simulator. Percentages (mean ± SD) of "continuous margins" were improved by applying the material in bulk and letting it self cure (54 ± 6) or dual cure (59 ± 9), and no significant differences were observed between these two groups and the positive control (44 ± 19). The present study showed that the dual-cured composite resin tested has the potential to be used as bulk filling material for Class 2 restorations. When used as filling materials, dual-cure composite resins placed in bulk can provide marginal adaptation similar to light-cured composites applied with a complex stratification technique.

The Seismicity of Two Hyperextended Margins

NASA Astrophysics Data System (ADS)

Redfield, Tim; Terje Osmundsen, Per

2013-04-01

A seismic belt marks the outermost edge of Scandinavia's proximal margin, inboard of and roughly parallel to the Taper Break. A similar near- to onshore seismic belt runs along its inner edge, roughly parallel to and outboard of the asymmetric, seaward-facing escarpment. The belts converge at both the northern and southern ends of Scandinavia, where crustal taper is sharp and the proximal margin is narrow. Very few seismic events have been recorded on the intervening, gently-tapering Trøndelag Platform. Norway's distribution of seismicity is systematically ordered with respect to 1) the structural templates of high-beta extension that shaped the thinning gradient during Late Jurassic or Early Cretaceous time, and 2) the topographically resurgent Cretaceous-Cenozoic "accommodation phase" family of escarpments that approximate the innermost limit of crustal thinning [See Redfield and Osmundsen (2012) for diagrams, definitions, discussion, and supporting citations.] Landwards from the belt of earthquake epicenters that mark the Taper Break the crust consistently thickens, and large fault arrays tend to sole out at mid crustal levels. Towards the sea the crystalline continental crust is hyperextended, pervasively faulted, and generally very thin. Also, faulting and serpentinization may have affected the uppermost parts of the distal margin's lithospheric mantle. Such contrasting structural conditions may generate a contrasting stiffness: for a given stress, more strain can be accommodated in the distal margin than in the less faulted proximal margin. By way of comparison, inboard of the Taper Break on the gently-tapered Trøndelag Platform, faulting was not penetrative. There, similar structural conditions prevail and proximal margin seismicity is negligible. Because stress concentration can occur where material properties undergo significant contrast, the necking zone may constitute a natural localization point for post-thinning phase earthquakes. In Scandinavia

Marginally outer trapped surfaces and symmetries

NASA Astrophysics Data System (ADS)

Carrasco, Alberto; Mars, Marc

2009-05-01

We study properties of outermost marginally outer trapped surfaces in slices of space-times possessing certain symmetries, like isometries, homotheties or conformal Killings. In particular, we find restrictions on these surfaces for the vector field generating the symmetry. As an application we give a result of non-existence of outermost marginally outer trapped surfaces in accelerated Friedmann-Lemaître-Roberson-Walker spacetimes.

Multi-modality photoacoustic tomography, ultrasound, and light sheet microscopy for volumetric tumor margin detection

NASA Astrophysics Data System (ADS)

Sangha, Gurneet S.; Hu, Bihe; Bolus, Daniel; Wang, Mei; Skidmore, Shelby J.; Sholl, Andrew B.; Brown, J. Quincy; Goergen, Craig J.

2018-02-01

Current methods for breast tumor margin detection are invasive, time consuming, and typically result in a reoperative rate of over 25%. This marks a clear clinical need to develop improved tools to intraoperatively differentiate negative versus positive tumor margins. Here, we utilize photoacoustic tomography (PAT), ultrasound (US), and inverted Selective Plane Illumination Microscopy (iSPIM) to assess breast tumor margins in eight human breast biopsies. Our PAT/US system consists of a tunable Nd:YAG laser (NT 300, EKSPLA) coupled with a 40MHz central frequency US probe (Vevo2100, FUJIFILM Visual Sonics). This system allows for the delivery of 10Hz, 5ns pulses with fluence of 40mJ/cm2 to the tissue with PAT and US axial resolutions of 125μm and 40μm, respectively. For this study, we used a linear stepper motor to acquire volumetric PAT/US images of the breast biopsies using 1100nm light to identify bloodrich "tumor" regions and 1210nm light to identify lipid-rich "healthy" regions. iSPIM (Applied Scientific Instrumentation) is an advanced microscopy technique with lateral resolution of 1.5μm and axial resolution of 7μm. We used 488nm laser excitation and acridine orange as a general comprehensive histology stain. Our results show that PAT/US can be used to identify lipid-rich regions, dense areas of arterioles and arteries, and other internal structures such as ducts. iSPIM images correlate well with histopathology slides and can verify nuclear features, cell type and density, stromal features, and microcalcifications. Together, this multimodality approach has the potential to improve tumor margin detection with a high degree of sensitivity and specificity.

A meta-analysis of self-reported achievement goals and nonself-report performance across three achievement domains (work, sports, and education).

PubMed

Van Yperen, Nico W; Blaga, Monica; Postmes, Tom

2014-01-01

During the past three decades, the achievement goal approach to achievement motivation has emerged as an influential area of research, and is dedicated to understanding the reasons behind the individual's drive to achieve competence and performance. However, the current literature on achievement goals is segmented rather than integrated. That is, citations across the three major and distinct achievement domains (work, education, and sports) are more the exception than the rule and similarities and differences between findings for the different achievement domains have yet to be tested. The purpose of the present study was to examine the relationships between self-reported achievement goals and nonself-report performance through meta-analysis, and the moderating potential of achievement domain. Identifying achievement domain as moderator improves our understanding to which contexts we can (not) generalize conclusions to, it helps to understand seemingly inconsistent findings, and opens avenues for future research on the underlying processes. Because the achievement goal (AG) measure used in a study is partially confounded with achievement domain, we examined the moderating role of this variable as well. Our findings suggest that - overall - approach goals (either mastery or performance) were associated positively with performance attainment, whereas avoidance goals (either mastery or performance) were associated negatively with performance attainment. These relationships were moderated by achievement domain. For example, relative to the education or work domain, in the sports domain, we did not observe negative correlations between avoidance goals and performance. The absence of statistical moderation due to AG measure suggests that the observed moderation of achievement domain cannot be explained by the AG measure utilized. We suggest further steps to integrate the achievement goal literature, and accordingly, to broaden and deepen understanding of performance

A Meta-Analysis of Self-Reported Achievement Goals and Nonself-Report Performance across Three Achievement Domains (Work, Sports, and Education)

PubMed Central

Van Yperen, Nico W.; Blaga, Monica; Postmes, Tom

2014-01-01

During the past three decades, the achievement goal approach to achievement motivation has emerged as an influential area of research, and is dedicated to understanding the reasons behind the individual’s drive to achieve competence and performance. However, the current literature on achievement goals is segmented rather than integrated. That is, citations across the three major and distinct achievement domains (work, education, and sports) are more the exception than the rule and similarities and differences between findings for the different achievement domains have yet to be tested. The purpose of the present study was to examine the relationships between self-reported achievement goals and nonself-report performance through meta-analysis, and the moderating potential of achievement domain. Identifying achievement domain as moderator improves our understanding to which contexts we can (not) generalize conclusions to, it helps to understand seemingly inconsistent findings, and opens avenues for future research on the underlying processes. Because the achievement goal (AG) measure used in a study is partially confounded with achievement domain, we examined the moderating role of this variable as well. Our findings suggest that – overall – approach goals (either mastery or performance) were associated positively with performance attainment, whereas avoidance goals (either mastery or performance) were associated negatively with performance attainment. These relationships were moderated by achievement domain. For example, relative to the education or work domain, in the sports domain, we did not observe negative correlations between avoidance goals and performance. The absence of statistical moderation due to AG measure suggests that the observed moderation of achievement domain cannot be explained by the AG measure utilized. We suggest further steps to integrate the achievement goal literature, and accordingly, to broaden and deepen understanding of

Creating double negative index materials using the Babinet principle with one metasurface

NASA Astrophysics Data System (ADS)

Zhang, Lei; Koschny, Thomas; Soukoulis, C. M.

2013-01-01

Metamaterials are patterned metallic structures which permit access to a novel electromagnetic response, negative index of refraction, impossible to achieve with naturally occurring materials. Using the Babinet principle, the complementary split ring resonator (SRR) is etched in a metallic plate to provide negative ɛ, with perpendicular direction. Here we propose a new design, etched in a metallic plate to provide negative magnetic permeability μ, with perpendicular direction. The combined electromagnetic response of this planar metamaterial, where the negative μ comes from the aperture and the negative ɛ from the remainder of the continuous metallic plate, allows achievement of a double negative index metamaterial (NIM) with only one metasurface and strong transmission. These designs can be used to fabricate NIMs at microwave and optical wavelengths and three-dimensional metamaterials.

Tectono-magmatic evolution at distal magma-poor rifted margins: insights of the lithospheric breakup at the Australia-Antarctica margins.

NASA Astrophysics Data System (ADS)

Gillard, Morgane; Autin, Julia; Manatschal, Gianreto

2015-04-01

The discovery of large domains of hyper-extended continental crust and exhumed mantle along many present-day magma-poor rifted margins questions the processes that play during the lithospheric breakup and the onset of seafloor spreading. In particular, the amount of magma and its relation to tectonic structures is yet little understood. Trying to find answers to these questions asks to work at the most distal parts of rifted margins where the transition from rifting to steady state seafloor spreading occurred. The Australian-Antarctic conjugated margins provide an excellent study area. Indeed, the central sector of the Great Australian Bight/Wilkes Land developed in a magma-poor probably ultra-slow setting and displays a complex and not yet well understood Ocean-Continent Transition (OCT). This distal area is well imaged by numerous high quality seismic lines covering the whole OCT and the steady-state oceanic crust. The deformation recorded in the sedimentary units along these margins highlights a migration of the deformation toward the ocean and a clear polyphase evolution. In particular, the observation that each tectono-sedimentary unit downlaps oceanwards onto the basement suggests that final rifting is associated with the creation of new depositional ground under conditions that are not yet those of a steady state oceanic crust. These observations lead to a model of evolution for these distal margins implying the development of multiple detachment systems organizing out-of-sequence, each new detachment fault developing into the previously exhumed basement. This spatial and temporal organization of fault systems leads to a final symmetry of exhumed domains at both conjugated margins. Magma appears to gradually increase during the margin development and is particularly present in the more distal domain where we can observe clear magma/fault interactions. We propose that the evolution of such rifted margins is linked to cycles of delocalisation

Flexible scintillator autoradiography for tumor margin inspection using 18F-FDG

NASA Astrophysics Data System (ADS)

Vyas, K. N.; Grootendorst, M.; Mertzanidou, T.; Macholl, S.; Stoyanov, D.; Arridge, S. R.; Tuch, D. S.

2018-03-01

Autoradiography potentially offers high molecular sensitivity and spatial resolution for tumor margin estimation. However, conventional autoradiography requires sectioning the sample which is destructive and labor-intensive. Here we describe a novel autoradiography technique that uses a flexible ultra-thin scintillator which conforms to the sample surface. Imaging with the flexible scintillator enables direct, high-resolution and high-sensitivity imaging of beta particle emissions from targeted radiotracers. The technique has the potential to identify positive tumor margins in fresh unsectioned samples during surgery, eliminating the processing time demands of conventional autoradiography. We demonstrate the feasibility of the flexible autoradiography approach to directly image the beta emissions from radiopharmaceuticals using lab experiments and GEANT-4 simulations to determine i) the specificity for 18F compared to 99mTc-labeled tracers ii) the sensitivity to detect signal from various depths within the tissue. We found that an image resolution of 1.5 mm was achievable with a scattering background and we estimate a minimum detectable activity concentration of 0.9 kBq/ml for 18F. We show that the flexible autoradiography approach has high potential as a technique for molecular imaging of tumor margins using 18F-FDG in a tumor xenograft mouse model imaged with a radiation-shielded EMCCD camera. Due to the advantage of conforming to the specimen, the flexible scintillator showed significantly better image quality in terms of tumor signal to whole-body background noise compared to rigid and optimally thick CaF2:Eu and BC400. The sensitivity of the technique means it is suitable for clinical translation.

Edge Effects along a Seagrass Margin Result in an Increased Grazing Risk on Posidonia australis Transplants

PubMed Central

Statton, John; Gustin-Craig, Samuel; Dixon, Kingsley W.; Kendrick, Gary A.

2015-01-01

A key issue in habitat restoration are the changes in ecological processes that occur when fragments of habitat are lost, resulting in the persistence of habitat-degraded margins. Margins often create or enhance opportunities for negative plant-herbivore interactions, preventing natural or assisted re-establishment of native vegetation into the degraded area. However, at some distance from the habitat margin these negative interactions may relax. Here, we posit that the intensity of species interactions in a fragmented Posidonia australis seagrass meadow may be spatially dependent on proximity to the seagrass habitat edge, whereby the risk of grazing is high and the probability of survival of seagrass transplants is low. To test this, transplants were planted 2 m within the meadow, on the meadow edge at 0m, and at 2m, 10m, 30m, 50m and 100m distance from the edge of the seagrass meadow into the unvegetated sand sheet. There was an enhanced grazing risk 0-10m from the edge, but decreased sharply with increasing distances (>30m). Yet, the risk of grazing was minimal inside the seagrass meadow, indicating that grazers may use the seagrass meadow for refuge but are not actively grazing within it. The relationship between short-term herbivory risk and long-term survival was not straightforward, suggesting that other environmental filters are also affecting survival of P. australis transplants within the study area. We found that daily probability of herbivory was predictable and operating over a small spatial scale at the edge of a large, intact seagrass meadow. These findings highlight the risk from herbivory can be high, and a potential contributing factor to seagrass establishment in restoration programs. PMID:26465926

Cenozoic ice sheet history from East Antarctic Wilkes Land continental margin sediments

USGS Publications Warehouse

Escutia, C.; De Santis, L.; Donda, F.; Dunbar, R.B.; Cooper, A. K.; Brancolini, Giuliano; Eittreim, S.L.

2005-01-01

regime during the Pliocene-Pleistocene, when most sediment delivered to the margin is trapped in the outer shelf and slope-forming steep prograding wedges. During the warmer but still polar, Holocene, biogenic sediment accumulates quickly in deep inner-shelf basins during the high-stand intervals. These sediments contain an ultrahigh resolution (annual to millennial) record of climate variability. Validation of our inferences about the nature and timing of Wilkes Land glacial sequences can be achieved by deep sampling (i.e., using IODP-type techniques). The most complete record of the long-term history of glaciation in this margin can be obtained by sampling both (1) the shelf, which contains the direct (presence or no presence of ice) but low-resolution record of glaciation, and (2) the rise, which contains the distal (cold vs. warm) but more complete record of glaciation. The Wilkes Land margin is the only known Antarctic margin where the presumed "onset" of glaciation unconformity (WL-U3) can be traced from shelf to the abyssal plain, allowing links between the proximal and the distal records of glaciation to be established. Additionally, the eastern segment of the Wilkes Land margin may be more sensitive to climate change because the East Antarctic Ice Sheet (EAIS) is grounded below sea level. Therefore, the Wilkes Land margin is not only an ideal location to obtain the long-term EAIS history but also to obtain the shorter-term record of ice sheet fluctuations at times that the East Antarctic Ice Sheet is thought to have been more stable (after 15 Ma-recent). ?? 2004 Elsevier B.V. All rights reserved.

A simulation study of spectral Čerenkov luminescence imaging for tumour margin estimation

NASA Astrophysics Data System (ADS)

Calvert, Nick; Helo, Yusef; Mertzanidou, Thomy; Tuch, David S.; Arridge, Simon R.; Stoyanov, Danail

2017-03-01

Breast cancer is the most common cancer in women in the world. Breast-conserving surgery (BCS) is a standard surgical treatment for breast cancer with the key objective of removing breast tissue, maintaining a negative surgical margin and providing a good cosmetic outcome. A positive surgical margin, meaning the presence of cancerous tissues on the surface of the breast specimen after surgery, is associated with local recurrence after therapy. In this study, we investigate a new imaging modality based on Cerenkov luminescence imaging (CLI) for the purpose of detecting positive surgical margins during BCS. We develop Monte Carlo (MC) simulations using the Geant4 nuclear physics simulation toolbox to study the spectrum of photons emitted given 18F-FDG and breast tissue properties. The resulting simulation spectra show that the CLI signal contains information that may be used to estimate whether the cancerous cells are at a depth of less than 1 mm or greater than 1 mm given appropriate imaging system design and sensitivity. The simulation spectra also show that when the source is located within 1 mm of the surface, the tissue parameters are not relevant to the model as the spectra do not vary significantly. At larger depths, however, the spectral information varies significantly with breast optical parameters, having implications for further studies and system design. While promising, further studies are needed to quantify the CLI response to more accurately incorporate tissue specific parameters and patient specific anatomical details.

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…

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…

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. Copyright © 2015 Elsevier B.V. All rights reserved.

M-Isomap: Orthogonal Constrained Marginal Isomap for Nonlinear Dimensionality Reduction.

PubMed

Zhang, Zhao; Chow, Tommy W S; Zhao, Mingbo

2013-02-01

Isomap is a well-known nonlinear dimensionality reduction (DR) method, aiming at preserving geodesic distances of all similarity pairs for delivering highly nonlinear manifolds. Isomap is efficient in visualizing synthetic data sets, but it usually delivers unsatisfactory results in benchmark cases. This paper incorporates the pairwise constraints into Isomap and proposes a marginal Isomap (M-Isomap) for manifold learning. The pairwise Cannot-Link and Must-Link constraints are used to specify the types of neighborhoods. M-Isomap computes the shortest path distances over constrained neighborhood graphs and guides the nonlinear DR through separating the interclass neighbors. As a result, large margins between both interand intraclass clusters are delivered and enhanced compactness of intracluster points is achieved at the same time. The validity of M-Isomap is examined by extensive simulations over synthetic, University of California, Irvine, and benchmark real Olivetti Research Library, YALE, and CMU Pose, Illumination, and Expression databases. The data visualization and clustering power of M-Isomap are compared with those of six related DR methods. The visualization results show that M-Isomap is able to deliver more separate clusters. Clustering evaluations also demonstrate that M-Isomap delivers comparable or even better results than some state-of-the-art DR algorithms.

17 CFR 242.404 - Type, form and use of margin.

Code of Federal Regulations, 2010 CFR

2010-04-01

... (CONTINUED) REGULATIONS M, SHO, ATS, AC, AND NMS AND CUSTOMER MARGIN REQUIREMENTS FOR SECURITY FUTURES Customer Margin Requirements for Security Futures § 242.404 Type, form and use of margin. (a) When margin... (§§ 242.400 through 242.406), provided that: (i) The customer waives any right to redeem the shares...

Complex shaped boron carbides from negative additive manufacturing

DOE PAGES

Lu, Ryan; Chandrasekaran, Swetha; Du Frane, Wyatt L.; ...

2018-03-13

In this paper, complex shaped boron carbide with carbon (B 4C/C) at near-full densities were achieved for the first time using negative additive manufacturing techniques via gelcasting. Negative additive manufacturing involves 3D printing of sacrificial molds used for casting negative copies. B 4C powder distributions and rheology of suspensions were optimized to successfully cast complex shapes. In addition to demonstrating scalability of these complex geometries, hierarchically meso-porous structures were also shown to be possible from this technique. Resorcinol-Formaldehyde (RF) polymer was selected as the gelling agent and can also pyrolyze into a carbon aerogel network to act as the sinteringmore » aid for B 4C. Finally, due to the highly effective distribution of in situ carbon for the B 4C matrix, near-full sintered density of 97–98% of theoretical maximum density was achieved.« less

Complex shaped boron carbides from negative additive manufacturing

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

Lu, Ryan; Chandrasekaran, Swetha; Du Frane, Wyatt L.

In this paper, complex shaped boron carbide with carbon (B 4C/C) at near-full densities were achieved for the first time using negative additive manufacturing techniques via gelcasting. Negative additive manufacturing involves 3D printing of sacrificial molds used for casting negative copies. B 4C powder distributions and rheology of suspensions were optimized to successfully cast complex shapes. In addition to demonstrating scalability of these complex geometries, hierarchically meso-porous structures were also shown to be possible from this technique. Resorcinol-Formaldehyde (RF) polymer was selected as the gelling agent and can also pyrolyze into a carbon aerogel network to act as the sinteringmore » aid for B 4C. Finally, due to the highly effective distribution of in situ carbon for the B 4C matrix, near-full sintered density of 97–98% of theoretical maximum density was achieved.« less

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

Multiple outer-reef tracts along the south Florida bank margin: Outlier reefs, a new windward-margin model

USGS Publications Warehouse

Lidz, Barbara H.; Hine, A.C.; Shinn, Eugene A.; Kindinger, Jack G.

1991-01-01

High-resolution seismic-reflection profiles off the lower Florida Keys reveal a multiple outlier-reef tract system ~0.5 to 1.5 km sea-ward of the bank margin. The system is characterized by a massive, outer main reef tract of high (28 m) unburied relief that parallels the margin and at least two narrower, discontinuous reef tracts of lower relief between the main tract and the shallow bank-margin reefs. The outer tract is ~0.5 to 1 km wide and extends a distance of ~57 km. A single pass divides the outer tract into two main reefs. The outlier reefs developed on antecedent, low-gradient to horizontal offbank surfaces, interpreted to be Pleistocene beaches that formed terracelike features. Radiocarbon dates of a coral core from the outer tract confirm a pre-Holocene age. These multiple outlier reefs represent a new windward-margin model that presents a significant, unique mechanism for progradation of carbonate platforms during periods of sea-level fluctuation. Infilling of the back-reef terrace basins would create new terraced promontories and would extend or "step" the platform seaward for hundreds of metres. Subsequent outlier-reef development would produce laterally accumulating sequences.

Second-year medical students' motivational beliefs, emotions, and achievement.

PubMed

Artino, Anthony R; La Rochelle, Jeffery S; Durning, Steven J

2010-12-01

A challenge for medical educators is to better understand the personal factors that lead to individual success in medical school and beyond. Recently, educational researchers in fields outside medicine have acknowledged the importance of motivation and emotion in students' learning and performance. These affective factors have received less emphasis in the medical education literature. This longitudinal study examined the relations between medical students' motivational beliefs (task value and self-efficacy), achievement emotions (enjoyment, anxiety and boredom) and academic achievement. Second-year medical students (n=136) completed motivational beliefs and achievement emotions surveys following their first and second trimesters, respectively. Academic achievement was operationalised as students' average course examination grades and national board shelf examination scores. The results largely confirmed the hypothesised relations between beliefs, emotions and achievement. Structural equation modelling revealed that task value beliefs were positively associated with course-related enjoyment (standardised regression coefficient [β] = 0.59) and were negatively related to boredom (β= -0.25), whereas self-efficacy beliefs were negatively associated with course-related anxiety only (β = -0.47). Furthermore, student enjoyment was positively associated with national board shelf examination score (β = 0.31), whereas anxiety and boredom were both negatively related to course examination grade (β= -0.36 and -0.27, respectively). The overall structural model accounted for considerable variance in each of the achievement outcomes: R(2) = 0.20 and 0.14 for the course examination grade and national board shelf examination score, respectively. This study suggests that medical students' motivational beliefs and achievement emotions are important contributors to their academic achievement. These results have implications for medical educators striving to understand the

Exploring the Margin Recipe for Online Adaptive Radiation Therapy for Intermediate-Risk Prostate Cancer: An Intrafractional Seminal Vesicles Motion Analysis

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

Sheng, Yang, E-mail: Yang.Sheng@duke.edu; Medical Physics Graduate Program, Duke University, Durham, North Carolina; Li, Taoran

Purpose: To provide a benchmark for seminal vesicle (SV) margin selection to account for intrafractional motion and to investigate the effectiveness of 2 motion surrogates in predicting intrafractional SV coverage. Methods and Materials: Fifteen prostate patients were studied. Each patient had 5 pairs (1 patient had 4 pairs) of pretreatment and posttreatment cone beam CTs (CBCTs). Each pair of CBCTs was registered on the basis of prostate fiducial markers. All pretreatment SVs were expanded with 1-, 2-, 3-, 4-, 5-, and 8-mm isotropic margins to form a series of planning target volumes, and their intrafractional coverage to the posttreatment SVmore » determined the “ground truth” for exact coverage. Two motion surrogates, the center of mass (COM) and the border of contour, were evaluated by the use of Pearson product-moment correlation coefficient and exponential fitting for predicting SV underdosage. Action threshold of each surrogate was calculated. The margin for each surrogate was calculated according to a traditional margin recipe. Results: Ninety-five percent posttreatment SV coverage was achieved in 9%, 53%, 73%, 86%, 95%, and 97% of fractions with 1-, 2-, 3-, 4-, 5-, and 8-mm margins, respectively. The 5-mm margins provided 95% intrafractional SV coverage in over 90% of fractions. The correlation between the COM and border was weak, moderate, and strong in the left-right (L-R), anterior-posterior (A-P), and superior-inferior (S-I) directions, respectively. Exponential fitting gave the underdosage threshold of 4.5 and 7.0 mm for the COM and border. The Van Herk margin recipe recommended 0-, 0.5-, and 0.8-mm margins in the L-R, A-P, and S-I directions based on the COM, and 1.2-, 3.9-, and 2.5-mm margins based on the border. Conclusions: Five-millimeter isotropic margins for the SV constitute the minimum required to mitigate the intrafractional motion. Both the COM and the border are acceptable predictors for SV underdosage with 4.5- and 7.0-mm action

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.

Passive margin evolution, initiation of subduction and the Wilson cycle

NASA Astrophysics Data System (ADS)

Cloetingh, S. A. P. L.; Wortel, M. J. R.; Vlaar, N. J.

1984-10-01

We have constructed finite element models at various stages of passive margin evolution, in which we have incorporated the system of forces acting on the margin, depth-dependent rheological properties and lateral variations across the margin. We have studied the interrelations between age-dependent forces, geometry and rheology, to decipher their net effect on the state of stress at passive margins. Lithospheric flexure induced by sediment loading dominates the state of stress at passive margins. This study has shown that if after a short evolution of the margin (time span a few tens of million years) subduction has not yet started, continued aging of the passive margin alone does not result in conditions more favourable for transformation into an active margin. Although much geological evidence is available in support of the key role small ocean basins play in orogeny and ophiolite emplacement, evolutionary frameworks of the Wilson cycle usually are cast in terms of opening and closing of wide ocean basins. We propose a more limited role for large oceans in the Wilson cycle concept.

Worst-Case Flutter Margins from F/A-18 Aircraft Aeroelastic Data

NASA Technical Reports Server (NTRS)

Lind, Rick; Brenner, Marty

1997-01-01

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, micron, computes a stability margin which 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 micron margins are robust margins which indicate worst-case stability estimates with respect to the defined uncertainty. Worst-case flutter margins are computed for the F/A-18 SRA 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.

Positive and Negative Impacts of Oil Palm Expansion in Indonesia and the Prospect to Achieve Sustainable Palm Oil

NASA Astrophysics Data System (ADS)

Shahputra, M. A.; Zen, Z.

2018-02-01

The aim of the study is to deepen understanding the role of palm oil on Indonesian economy, poverty elevation and to investigate the positive and negative impacts of oil palm expansion, due to the burden of GHG emissions; and prospect to be more sustainable palm oil industry. The statistics show that average rural poverty tends to be lower and Gross Regional Product tends to be higher in provinces which have greater levels of oil palm cultivation. Indonesian oil palm will grow from 10.6 in 2013 to 13.7 million ha by 2020. This will release 135.59 million tons of CO2 if nothing is done to mitigate BAU emissions. Unless there are sustained efforts to redirect development and expansion of oil palm, plantation growth will continue to encroach on intact forest and peat land.. In fact Indonesia has large areas of degraded land, an estimated total 19,144,000 ha is available for planting oil palm and other crops. A large-scale expansion program driven by estate companies needs to be accompanied by effective smallholder development program in order to achieve the best outcome for local farmers and avoid the conflicts.

Surgical treatment of advanced pellucid marginal degeneration.

PubMed

Rasheed, K; Rabinowitz, Y S

2000-10-01

To determine the efficacy of simultaneous peripheral crescentic lamellar keratoplasty (LK) and central penetrating keratoplasty (PK) for advanced pellucid marginal degeneration (PMD). Retrospective, noncomparative, interventional case series. Five patients with advanced PMD. Simultaneous peripheral crescentic LK and central PK followed by selective suture removal and astigmatic keratotomy in the postoperative period. These included interval of time required for visual rehabilitation, best spectacle-corrected visual acuity achieved, and amount of corneal astigmatism, as measured by videokeratography. Measuring the change in corneal astigmatism by videokeratography over the subsequent follow-up period after spectacle correction had been prescribed assessed stability of the achieved refraction. Visual acuity results were 20/40 in three eyes, 20/80 in one eye, and 20/400 in one eye. The latter two had decreased acuity from posterior subcapsular cataract formation, which may have been caused by topical steroid use. The time required for visual rehabilitation ranged from 5.13 to 10.93 (mean, 9.92) months, and the amount of corneal astigmatism at the end of this period ranged from 0.3 diopters (D) to 5.3 D. A tendency for an increase in "with the rule astigmatism" after the rehabilitation period was noted. Two patients had elevations of intraocular pressure that responded to reduction in topical steroid dose. The short-term results with this technique are excellent in that it provides early and stable visual rehabilitation in patients with advanced PMD. Low to moderate levels of postkeratoplasty astigmatism were achieved in all the eyes treated. The usual tendency of an increase in "against the rule astigmatism" that occurs when PK alone is done for PMD was eliminated.

Sensitivity of postplanning target and OAR coverage estimates to dosimetric margin distribution sampling parameters

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

Xu Huijun; Gordon, J. James; Siebers, Jeffrey V.

2011-02-15

{omega} or {omega}{sub eff} and {delta}. Results: The accuracy of coverage estimates depends on angular and radial DMD sampling parameters {omega} or {omega}{sub eff} and {delta}, as well as the employed sampling technique. Target |{Delta}Q|<1% and OAR |{Delta}Q|<3% can be achieved with sampling parameters {omega} or {omega}{sub eff}=20 deg., {delta}=1 mm. Better accuracy (target |{Delta}Q|<0.5% and OAR |{Delta}Q|<{approx}1%) can be achieved with {omega} or {omega}{sub eff}=10 deg., {delta}=0.5 mm. As the number of sampling points decreases, the isotropic sampling method maintains better accuracy than fixed angular sampling. Conclusions: Coverage estimates for post-planning evaluation are essential since coverage values of targets and OARs often differ from the values implied by the static margin-based plans. Finer sampling of the DMD enables more accurate assessment of the effect of geometric uncertainties on coverage estimates prior to treatment. DMD sampling with {omega} or {omega}{sub eff}=10 deg. and {delta}=0.5 mm should be adequate for planning purposes.« less

Single-Center Experience Using Marginal Liver Grafts in Korea.

PubMed

Park, P-J; Yu, Y-D; Yoon, Y-I; Kim, S-R; Kim, D-S

2018-05-01

Liver transplantation (LT) is an established therapeutic modality for patients with end-stage liver disease. The use of marginal donors has become more common worldwide due to the sharp increase in recipients, with a consequent shortage of suitable organs. We analyzed our single-center experience over the last 8 years in LT to evaluate the outcomes of using so-called "marginal donors." We retrospectively analyzed the database of all LTs performed at our institution from 2009 to 2017. Only patients undergoing deceased-donor LTs were analyzed. Marginal grafts were defined as livers from donors >60 years of age, livers from donors with serum sodium levels >155 mEq, graft steatosis >30%, livers with cold ischemia time ≥12 hours, livers from donors who were hepatitis B or C virus positive, livers recovered from donation after cardiac death, and livers split between 2 recipients. Patients receiving marginal grafts (marginal group) were compared with patients receiving standard grafts (standard group). A total of 106 patients underwent deceased-donor LT. There were 55 patients in the standard group and 51 patients in the marginal group. There were no significant differences in terms of age, sex, Model for End-Stage Liver Disease score, underlying liver disease, presence of hepatocellular carcinoma, and hospital stay between the 2 groups. Although the incidence of acute cellular rejection, cytomegalovirus infection, and postoperative complications was similar between the 2 groups, the incidence of early allograft dysfunction was higher in the marginal group. With a median follow-up of 26 months, the 1-, 3-, and 5-year overall and graft (death-censored) survivals in the marginal group were 85.5%, 75%, and 69.2% and 85.9%, 83.6%, and 77.2%, respectively. Patient overall survival and graft survival (death-censored) were significantly lower in the marginal group (P = .023 and P = .048, respectively). On multivariate analysis, receiving a marginal graft (hazard ratio [HR

Role of Adjuvant Therapy for Node-Negative Lung Cancer Invading the Chest Wall.

PubMed

Gao, Sarah J; Corso, Christopher D; Blasberg, Justin D; Detterbeck, Frank C; Boffa, Daniel J; Decker, Roy H; Kim, Anthony W

2017-03-01

The present study investigated the effect of adjuvant chemotherapy and radiation on survival among patients undergoing chest wall resection for T3N0 non-small cell lung cancer (NSCLC). Patients with T3N0 NSCLC who underwent chest wall resection were identified in the National Cancer Data Base in 2004 to 2012. The cohort was divided into patients who had received adjuvant chemotherapy, radiation therapy, chemoradiation therapy, or no adjuvant treatment. Kaplan-Meier and log-rank tests were used to compare overall survival, and a bootstrapped Cox proportional hazards model was used to determine the significant contributors to survival. A subset analysis was performed with stratification by margin status and tumor size. Of 759 patients identified, 42.0% underwent surgery alone, 23.3% underwent surgery followed by chemotherapy, 22.3% underwent surgery followed by chemoradiation therapy, and 12.3% underwent surgery followed by radiotherapy alone. Tumors > 4 cm benefited from adjuvant chemotherapy and radiation therapy in the multivariable analysis, and those ≤ 4 cm benefited only from adjuvant chemotherapy. The subgroup analysis by margin status identified that margin-positive patients with tumors > 4 cm benefited significantly from either adjuvant chemoradiation therapy or radiation therapy alone. T3N0 NSCLC with chest wall invasion requires unique management compared with other stage IIB tumors. An important determinant of management is tumor size, with tumors ≤ 4 cm benefiting from adjuvant chemotherapy and tumors > 4 cm benefiting from adjuvant chemotherapy if margin negative and adjuvant chemoradiation therapy or radiotherapy if margin positive. Copyright © 2016 Elsevier Inc. All rights reserved.

Training for assessment of negative symptoms of schizophrenia across languages and cultures: comparison of the NSA-16 with the PANSS Negative Subscale and Negative Symptom factor.

PubMed

Daniel, David G; Alphs, Larry; Cazorla, Pilar; Bartko, John J; Panagides, John

2011-07-01

The 16-item Negative Symptom Assessment scale (NSA-16) has been validated in English-speaking raters. We analyzed the level of agreement achieved among raters of different nationalities using the NSA-16 and the Positive and Negative Syndrome Scale (PANSS) negative subscale and Marder negative factor. Raters participating in two international trials were trained in the use of each instrument through lectures and feedback on their ratings of at least one videotaped interview of a schizophrenic patient. Overall and regional (North America, Western Europe, Eastern Europe, South/Central America, and Australia and South Africa combined) kappa values were calculated and mean total scores were compared (1-way analysis of variance) by region for each instrument. In addition, within-scales variance was calculated by item to help identify negative symptoms that were particularly challenging to obtain agreement on across cultures. In the combined group of international raters, the kappa values for ratings of the NSA-16, PANSS negative subscale, and Marder negative factors were 0.89, 0.84, and 0.82, respectively. Kappa values calculated by geographic region ranged from 0.87 to 0.94 for the NSA-16 compared with 0.82 to 0.86 for the PANSS negative subscale and 0.79 to 0.87 for the PANSS Marder negative factor. Despite cultural and linguistic differences among raters, standardizing measurement of negative symptoms in international clinical trials is possible using available rating scales: NSA-16, PANSS negative subscale, and Marder negative subscale. Agreement among raters was at least as high using the NSA-16 as using the PANSS instruments.

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.

Exploring the Subtleties of Inverse Probability Weighting and Marginal Structural Models.

PubMed

Breskin, Alexander; Cole, Stephen R; Westreich, Daniel

2018-05-01

Since being introduced to epidemiology in 2000, marginal structural models have become a commonly used method for causal inference in a wide range of epidemiologic settings. In this brief report, we aim to explore three subtleties of marginal structural models. First, we distinguish marginal structural models from the inverse probability weighting estimator, and we emphasize that marginal structural models are not only for longitudinal exposures. Second, we explore the meaning of the word "marginal" in "marginal structural model." Finally, we show that the specification of a marginal structural model can have important implications for the interpretation of its parameters. Each of these concepts have important implications for the use and understanding of marginal structural models, and thus providing detailed explanations of them may lead to better practices for the field of epidemiology.

A comparison of the marginal adaptation of cathode-arc vapor-deposited titanium and cast base metal copings

PubMed Central

Wu, JC; Lai, LC; Sheets, CG; Earthman, J; Newcomb, R

2011-01-01

Statement of problem A new fabrication process has been developed where a titanium coping, which has a gold colored titanium nitride outer layer can be reliably fused to porcelain, but the marginal adaptation characteristics are still undetermined. Purpose The primary purpose of this study is to compare the rate of Clinically Acceptable Marginal Adaptation (CAMA-defined as a marginal gap mean ≤60 μm) of cathode-arc vapor-deposited titanium with the CAMA rate for the cast base metal copings. In addition, the study will evaluate the marginal gap scores themselves to assess their mean difference between the two study groups. Finally, the study will present two analyses of group differences in variability to support the contention that the titanium copings perform more consistently than their base metal counterparts. Material and methods Thirty-seven cathode-arc vapor-deposited titanium copings and 40 cast base metal copings were evaluated by computer-based image analysis using an optical microscope. The conventional lost wax technique was used to fabricate the 40 cast base metal copings that were 0.3 mm thick. The titanium copings were 0.3 mm thick and were formed by a collection of atomic titanium vapor onto a refractory die duplicate in a high vacuum chamber. Fifty vertical marginal gap measurements were collected from each of the 77 copings and the mean of these measurements was computed to form a gap score for each coping. Next, the gap score was compared to the 60 μm criterion to classify each coping as to whether it did or did not achieve Clinically Acceptable Marginal Adaption (CAMA). A comparison of the CAMA rates for each type of coping was used to address the primary purpose of this study. In addition, the gap scores themselves were used to test the (one-sided) hypothesis that the mean of the titanium gap scores is smaller than the mean of the base metal gap scores. Finally, the assertion that the titanium copings provide more consistency in their

Sarcopenia Is Negatively Related to High Gravitational Impacts Achieved From Day-to-day Physical Activity

PubMed Central

Hartley, April; Gregson, Celia L; Hannam, Kimberly; Deere, Kevin C; Clark, Emma M; Tobias, Jon H

2018-01-01

Abstract Background Sarcopenia has been associated with reduced physical activity (PA). We aimed to determine if sarcopenia, and specific components of muscle size, function, and physical performance, are associated with high impacts achieved during habitual PA, as these are related to bone strength in community-dwelling older women. Methods Participants were older women from the Cohort of Skeletal Health in Bristol and Avon. We defined sarcopenia using the EWGSOP criteria. Lower limb peak muscle power and force were assessed using Jumping Mechanography (JM). High vertical impacts were assessed by tri-axial accelerometry (at least 1.5g above gravity). Cross-sectional associations were analyzed by linear regression, adjusting for age, height and weight (or fat mass for models including appendicular lean mass index), comorbidities, smoking, alcohol, and Index of Multiple Deprivation. Results Our analyses included 380 participants, with mean age 76.7 (SD 3.0) years; 242 (64%) also completed JM. In age-adjusted analysis, a negative relationship was observed between severity of sarcopenia and high, but not medium or low, impacts (p = .03 for trend). Regarding components of sarcopenia underlying this relationship, multivariable analyses revealed that gait speed (β 1.47 [95% CI 1.14, 1.89], [β-1] reflects the proportionate increase in high impacts per SD increase in exposure) and peak force (1.40 [1.07, 1.84]) were independently associated with high impacts. Conclusions Older women with sarcopenia experienced fewer bone-strengthening high impacts than those with presarcopenia or without sarcopenia. To increase bone strengthening activity in older women, interventions need to improve both lower limb muscle force and walking speed. PMID:29182712

Polystyrene negative resist for high-resolution electron beam lithography

PubMed Central

2011-01-01

We studied the exposure behavior of low molecular weight polystyrene as a negative tone electron beam lithography (EBL) resist, with the goal of finding the ultimate achievable resolution. It demonstrated fairly well-defined patterning of a 20-nm period line array and a 15-nm period dot array, which are the densest patterns ever achieved using organic EBL resists. Such dense patterns can be achieved both at 20 and 5 keV beam energies using different developers. In addition to its ultra-high resolution capability, polystyrene is a simple and low-cost resist with easy process control and practically unlimited shelf life. It is also considerably more resistant to dry etching than PMMA. With a low sensitivity, it would find applications where negative resist is desired and throughput is not a major concern. PMID:21749679

Seismic analysis of clinoform depositional sequences and shelf-margin trajectories in Lower Cretaceous (Albian) strata, Alaska North Slope

USGS Publications Warehouse

Houseknecht, D.W.; Bird, K.J.; Schenk, C.J.

2009-01-01

Lower Cretaceous strata beneath the Alaska North Slope include clinoform depositional sequences that filled the western Colville foreland basin and overstepped the Beaufort rift shoulder. Analysis of Albian clinoform sequences with two-dimensional (2D) seismic data resulted in the recognition of seismic facies inferred to represent lowstand, transgressive and highstand systems tracts. These are stacked to produce shelf-margin trajectories that appear in low-resolution seismic data to alternate between aggradational and progradational. Higher-resolution seismic data reveal shelf-margin trajectories that are more complex, particularly in net-aggradational areas, where three patterns commonly are observed: (1) a negative (downward) step across the sequence boundary followed by mostly aggradation in the lowstand systems tract (LST), (2) a positive (upward) step across the sequence boundary followed by mostly progradation in the LST and (3) an upward backstep across a mass-failure d??collement. These different shelf-margin trajectories are interpreted as (1) fall of relative sea level below the shelf edge, (2) fall of relative sea level to above the shelf edge and (3) mass-failure removal of shelf-margin sediment. Lowstand shelf margins mapped using these criteria are oriented north-south in the foreland basin, indicating longitudinal filling from west to east. The shelf margins turn westward in the north, where the clinoform depositional system overstepped the rift shoulder, and turn eastward in the south, suggesting progradation of depositional systems from the ancestral Brooks Range into the foredeep. Lowstand shelf-margin orientations are consistently perpendicular to clinoform-foreset-dip directions. Although the Albian clinoform sequences of the Alaska North Slope are generally similar in stratal geometry to clinoform sequences elsewhere, they are significantly thicker. Clinoform-sequence thickness ranges from 600-1000 m in the north to 1700-2000 m in the south

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

Effect of posterior crown margin placement on gingival health.

PubMed

Reitemeier, Bernd; Hänsel, Kristina; Walter, Michael H; Kastner, Christian; Toutenburg, Helge

2002-02-01

The clinical impact of posterior crown margin placement on gingival health has not been thoroughly quantified. This study evaluated the effect of posterior crown margin placement with multivariate analysis. Ten general dentists reviewed 240 patients with 480 metal-ceramic crowns in a prospective clinical trial. The alloy was randomly selected from 2 high gold, 1 low gold, and 1 palladium alloy. Variables were the alloy used, oral hygiene index score before treatment, location of crown margins at baseline, and plaque index and sulcus bleeding index scores recorded for restored and control teeth after 1 year. The effect of crown margin placement on sulcular bleeding and plaque accumulation was analyzed with regression models (P<.05). The probability of plaque at 1 year increased with increasing oral hygiene index score before treatment. The lingual surfaces demonstrated the highest probability of plaque. The risk of bleeding at intrasulcular posterior crown margins was approximately twice that at supragingival margins. Poor oral hygiene before treatment and plaque also were associated with sulcular bleeding. Facial sites exhibited a lower probability of sulcular bleeding than lingual surfaces. Type of alloy did not influence sulcular bleeding. In this study, placement of crown margins was one of several parameters that affected gingival health.

Resection margin influences survival after pancreatoduodenectomy for distal cholangiocarcinoma.

PubMed

Chua, Terence C; Mittal, Anubhav; Arena, Jenny; Sheen, Amy; Gill, Anthony J; Samra, Jaswinder S

2017-06-01

Distal cholangiocarcinoma remains a rare cancer associated with a dismal outcome. There is a lack of effective treatment options and where disease is amendable to resection, surgery affords the best potential for long-term survival. The aim of this study was to examine the survival outcomes and prognostic factors of patients undergoing pancreatoduodenectomy for distal cholangiocarcinoma. Between January 2004 to May 2016, patients who had undergone pancreatoduodenectomy with histologically proven distal cholangiocarcinoma were identified. Clinicopathologic data and survival outcomes were reported. Pancreatoduodenectomy alone was performed in 20 patients (71%) and eight patients (29%) required concomitant vascular resection. The major complication rate was 43% (n = 12). Nineteen patients (68%) had node positive disease. Eighteen patients (64%) had R0 resection. The median survival was 36 months (95%CI 9.7 to 63.8) and 5-year survival rate was 24%. Univariate analysis identified ASA (P < 0.001), tumor grade (P = 0.009) and margin status (P = 0.042) as prognostic factors associated with survival. Long-term survival may be achieved in selected patients undergoing pancreatoduodenectomy for distal cholangiocarcinoma, especially in patients who achieved an R0 resection. Copyright © 2016 Elsevier Inc. All rights reserved.

Incidence and location of positive surgical margin among open, laparoscopic and robot-assisted radical prostatectomy in prostate cancer patients: a single institutional analysis.

PubMed

Koizumi, Atsushi; Narita, Shintaro; Nara, Taketoshi; Takayama, Koichiro; Kanda, Sohei; Numakura, Kazuyuki; Tsuruta, Hiroshi; Maeno, Atsushi; Huang, Mingguo; Saito, Mitsuru; Inoue, Takamitsu; Tsuchiya, Norihiko; Satoh, Shigeru; Nanjo, Hiroshi; Habuchi, Tomonori

2018-06-19

To evaluate the positive surgical margin rates and locations in radical prostatectomy among three surgical approaches, including open radical prostatectomy, laparoscopic radical prostatectomy and robot-assisted radical prostatectomy. We retrospectively reviewed clinical outcomes at our institution of 450 patients who received radical prostatectomy. Multiple surgeons were involved in the three approaches, and a single pathologist conducted the histopathological diagnoses. Positive surgical margin rates and locations among the three approaches were statistically assessed, and the risk factors of positive surgical margin were analyzed. This study included 127, 136 and 187 patients in the open radical prostatectomy, laparoscopic radical prostatectomy and robot-assisted radical prostatectomy groups, respectively. The positive surgical margin rates were 27.6% (open radical prostatectomy), 18.4% (laparoscopic radical prostatectomy) and 13.4% (robot-assisted radical prostatectomy). In propensity score-matched analyses, the positive surgical margin rate in the robot-assisted radical prostatectomy was significantly lower than that in the open radical prostatectomy, whereas there was no significant difference in the positive surgical margin rates between robot-assisted radical prostatectomy and laparoscopic radical prostatectomy. In the multivariable analysis, PSA level at diagnosis and surgical approach (open radical prostatectomy vs robot-assisted radical prostatectomy) were independent risk factors for positive surgical margin. The apex was the most common location of positive surgical margin in the open radical prostatectomy and laparoscopic radical prostatectomy groups, whereas the bladder neck was the most common location in the robot-assisted radical prostatectomy group. The significant difference of positive surgical margin locations continued after the propensity score adjustment. Robot-assisted radical prostatectomy may potentially achieve the lowest positive

Comparison of Marginal Circumference of Two Different Pre-Crimped Stainless Steel Crowns for Primary Molars After Re-Crimping

PubMed Central

Afshar, Hossein; Ghandehari, Mehdi; Soleimani, Banafsheh

2015-01-01

Objectives: It is not clear what type of pre-crimped crown is more successful in achieving greater marginal adaptation following re-crimping. This study aimed to assess the changes in the circumference of 3M ESPE and MIB pre-crimped stainless steel crowns (SSCs) for the primary maxillary and mandibular first and second molars following re-crimping. Materials and Methods: This was an in-vitro, experimental study. Initial photographs were obtained from the margins of 3M and MIB SSCs for the upper and lower primary molars using a digital camera. Crown margins were crimped by applying 0.2N force using 114 and 137 pliers. Post-crimping photographs were also obtained and the changes in crown circumference after crimping were calculated using AutoCad software. The percentage of reduction in the circumference of crowns for each tooth was statistically analyzed based on the type of crown using student t-test. The effect of crown design and the associated teeth on the decreased circumference percentage was statistically analyzed by two-sided ANOVA. Results: The percentage of reduction in lower E SSC circumference was 3.71±0.39% in MIB and 6.29±0.62% in 3M crowns. These values were 3.55±0.55% and 7.15±1.13% for the lower Ds, and 3.95±0.43 and 6.24±0.85% for the upper Ds, respectively. For the upper Es, these values were found to be 3.12±0.65% and 5.14±0.94%, respectively. For each tooth, a significant difference was found between MIB and 3M SSCs in terms of the percentage of reduction in crown circumference following crimping. The magnitude of this reduction was smaller in MIB compared to 3M SSCs (P<0.001). Conclusion: Considering the significant reduction in the marginal circumference of precrimped SSCs following re-crimping, it appears that this manipulation must be necessarily performed for MIB and 3M pre-crimped SSCs. By using 3M SSCs, higher marginal adaptation can be achieved following crimping. PMID:27559353

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.

'Marginal' BY Draconis stars

NASA Technical Reports Server (NTRS)

Bopp, Bernard W.

1987-01-01

Spectroscopic observations of 52 dK-dM stars, obtained at 640-665 nm (with spectral resolution 70-90 pm) using CCD detectors on the coude-feed telescope at KPNO since 1982, are reported. Data for four stars found to have diluted absorption or weak emission above continuum at H-alpha are presented in tables and spectra and discussed in detail. These objects (Gliese numbers 256, 425A, 900, and 907.1) are shown to be 'marginal' BY Dra stars, single objects of age 2.5-3 Gyr with activity and rotational velocity (3-5 km/s) between those of normal dM stars and those of true BY Dra stars. An explanation based on evolution from the BY Dra stage through marginal BY Dra to inactive dM is proposed.

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…

Applied Time Domain Stability Margin Assessment for Nonlinear Time-Varying Systems

NASA Technical Reports Server (NTRS)

Kiefer, J. M.; Johnson, M. D.; Wall, J. H.; Dominguez, A.

2016-01-01

The baseline stability margins for NASA's Space Launch System (SLS) launch vehicle were generated via the classical approach of linearizing the system equations of motion and determining the gain and phase margins from the resulting frequency domain model. To improve the fidelity of the classical methods, the linear frequency domain approach can be extended by replacing static, memoryless nonlinearities with describing functions. This technique, however, does not address the time varying nature of the dynamics of a launch vehicle in flight. An alternative technique for the evaluation of the stability of the nonlinear launch vehicle dynamics along its trajectory is to incrementally adjust the gain and/or time delay in the time domain simulation until the system exhibits unstable behavior. This technique has the added benefit of providing a direct comparison between the time domain and frequency domain tools in support of simulation validation. This technique was implemented by using the Stability Aerospace Vehicle Analysis Tool (SAVANT) computer simulation to evaluate the stability of the SLS system with the Adaptive Augmenting Control (AAC) active and inactive along its ascent trajectory. The gains for which the vehicle maintains apparent time-domain stability defines the gain margins, and the time delay similarly defines the phase margin. This method of extracting the control stability margins from the time-domain simulation is relatively straightforward and the resultant margins can be compared to the linearized system results. The sections herein describe the techniques employed to extract the time-domain margins, compare the results between these nonlinear and the linear methods, and provide explanations for observed discrepancies. The SLS ascent trajectory was simulated with SAVANT and the classical linear stability margins were evaluated at one second intervals. The linear analysis was performed with the AAC algorithm disabled to attain baseline stability

Realistic respiratory motion margins for external beam partial breast irradiation

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

Conroy, Leigh; Quirk, Sarah; Department of Physics and Astronomy, University of Calgary, Calgary, Alberta T2N 1N4

Purpose: Respiratory margins for partial breast irradiation (PBI) have been largely based on geometric observations, which may overestimate the margin required for dosimetric coverage. In this study, dosimetric population-based respiratory margins and margin formulas for external beam partial breast irradiation are determined. Methods: Volunteer respiratory data and anterior–posterior (AP) dose profiles from clinical treatment plans of 28 3D conformal radiotherapy (3DCRT) PBI patient plans were used to determine population-based respiratory margins. The peak-to-peak amplitudes (A) of realistic respiratory motion data from healthy volunteers were scaled from A = 1 to 10 mm to create respiratory motion probability density functions. Dosemore » profiles were convolved with the respiratory probability density functions to produce blurred dose profiles accounting for respiratory motion. The required margins were found by measuring the distance between the simulated treatment and original dose profiles at the 95% isodose level. Results: The symmetric dosimetric respiratory margins to cover 90%, 95%, and 100% of the simulated treatment population were 1.5, 2, and 4 mm, respectively. With patient set up at end exhale, the required margins were larger in the anterior direction than the posterior. For respiratory amplitudes less than 5 mm, the population-based margins can be expressed as a fraction of the extent of respiratory motion. The derived formulas in the anterior/posterior directions for 90%, 95%, and 100% simulated population coverage were 0.45A/0.25A, 0.50A/0.30A, and 0.70A/0.40A. The differences in formulas for different population coverage criteria demonstrate that respiratory trace shape and baseline drift characteristics affect individual respiratory margins even for the same average peak-to-peak amplitude. Conclusions: A methodology for determining population-based respiratory margins using real respiratory motion patterns and dose profiles in the AP

A boosted negative bit-line SRAM with write-assisted cell in 45 nm CMOS technology

NASA Astrophysics Data System (ADS)

Bhatnagar, Vipul; Kumar, Pradeep; Pandey, Neeta; Pandey, Sujata

2018-02-01

A new 11 T SRAM cell with write-assist is proposed to improve operation at low supply voltage. In this technique, a negative bit-line voltage is applied to one of the write bit-lines, while a boosted voltage is applied to the other write bit-line where transmission gate access is used in proposed 11 T cell. Supply voltage to one of the inverters is interrupted to weaken the feedback. Improved write feature is attributed to strengthened write access devices and weakened feedback loop of cell at the same time. Amount of boosting required for write performance improvement is also reduced due to feedback weakening, solving the persistent problem of half-selected cells and reliability reduction of access devices with the other suggested boosted and negative bit-line techniques. The proposed design improves write time by 79%, 63% and slower by 52% with respect to LP 10 T, WRE 8 T and 6 T cells respectively. It is found that write margin for the proposed cell is improved by about 4×, 2.4× and 5.37× compared to WRE8 T, LP10 T and 6 T respectively. The proposed cell with boosted negative bit line (BNBL) provides 47%, 31%, and 68.4% improvement in write margin with respect to no write-assist, negative bit line (NBL) and boosted bit line (BBL) write-assist respectively. Also, new sensing circuit with replica bit-line is proposed to give a more precise timing of applying boosted voltages for improved results. All simulations are done on TSMC 45 nm CMOS technology.

17 CFR 41.47 - Withdrawal of margin.

Code of Federal Regulations, 2010 CFR

2010-04-01

... PRODUCTS Customer Accounts and Margin Requirements § 41.47 Withdrawal of margin. (a) By the customer... positions in the account under this Regulation (Subpart E, §§ 41.42 through 41.49). (b) By the security...) Interest charged on credit maintained in the account; (3) Communication or shipping charges with respect to...

Achieving excellence in the management of accounts receivable.

PubMed

Ladewig, T L; Hecht, B A

1993-09-01

Recent changes in healthcare reimbursement rules and practices have made the task of accounts receivable management a particularly demanding one for most financial managers. One multihospital system, after pursuing numerous strategies to reduce its accounts receivable with only marginal levels of success, launched a systemwide initiative to share both the positive and the negative accounts receivable management experiences of each department at each hospital in the system with all patient accounting staff. The objective of the initiative was to use the lessons learned from those experiences to attain excellence in accounts receivable management throughout the system. The ultimate success of the initiative is detailed in the following article.

The crustal structure of the southern Argentine margin

NASA Astrophysics Data System (ADS)

Becker, Katharina; Franke, Dieter; Schnabel, Michael; Schreckenberger, Bernd; Heyde, Ingo; Krawczyk, Charlotte M.

2012-06-01

Multichannel reflection seismic profiles, combined with gravimetric and magnetic data provide insight into the crustal structure of the southernmost Argentine margin, at the transition from a rifted to a transform margin and outline the extent of the North Falkland Graben. Based on these data, we establish a regional stratigraphic model for the post-rift sediments, comprising six marker horizons with a new formation in the Barremian/Lower Cretaceous. Our observations support that a N-S trending subsidiary branch of the North Falkland Graben continues along the continental shelf and slope to the Argentine basin. During the rift phase, a wide shelf area was affected by the E-W extension, subsequently forming the North Falkland Graben and the subsidiary branch along which finally breakup occurred. We propose the division of the margin in two segments: a N-S trending rifted margin and an E-W trending transform margin. This is further underpinned by crustal scale gravity modelling. Three different tectono-dynamic processes shaped the study area. (1) The Triassic/Early Jurassic extensional phase resulting in the formation of the North Falkland Graben and additional narrower rift grabens ended synchronously with the breakup of the South Atlantic in the early Valanginian. (2) Extensional phase related to the opening of the South Atlantic. (3) The transform margin was active in the study area from about Hauterivian times and activity lasted until late Cretaceous/early Cenozoic. Both, the rifted margin and the transform margin are magma-poor. Very limited structures may have a volcanic origin but are suggested to be post-rift. The oceanic crust was found to be unusually thin, indicating a deficit in magma supply during formation. These findings in combination with the proposed breakup age in the early Valanginian that considerably predates the formation of the Paraná-Etendeka continental flood basalt provinces in Brazil and Namibia question the influence of the Tristan da

Catastrophic Bleeding From a Marginal Ulcer After Gastric Bypass

PubMed Central

Sidani, Shafik; Akkary, Ehab

2013-01-01

Marginal ulceration at the gastrojejunal anastomosis is a common complication following Roux-Y gastric bypass (RYGB). Hemodynamically significant hemorrhagic marginal ulcers are usually treated either endoscopically or surgically. We describe a unique case of life-threatening hemorrhagic marginal ulcer eroding into the main splenic artery. This condition was initially managed with angiographic embolization, followed by surgical intervention. PMID:23743389

Comparative analysis of two measurement methods for marginal fit in metal-ceramic and zirconia posterior FPDs.

PubMed

Gonzalo, Esther; Suárez, María J; Serrano, Benjamin; Lozano, José F L

2009-01-01

The purpose of this study was to compare two measurement methods for the external marginal fit of zirconia posterior fixed partial dentures (FPDs) fabricated using computer-aided design/manufacturing technology and metal-ceramic posterior FPDs fabricated using the conventional lost-wax technique. The null hypothesis was that there would be no differences between the measurement methods. Forty standardized steel specimens were prepared to receive posterior three-unit FPDs. Specimens were divided into four groups (n = 10): (1) metal-ceramic, (2) Procera Bridge Zirconia, (3) Lava AllCeramic System, and (4) Vita In-Ceram YZ 2000. All FPDs were luted with glass-ionomer cement (Ketac Cem EasyMix, 3M ESPE). Two measurement methods were used to analyze marginal fit: an image analysis (IA) program and a scanning electron microscope (SEM) (JEOL JSM-6400) with magnifications of 340 and 31,000, respectively. Marginal fit was measured at the same point on each abutment. Significant interaction was observed between measurement method and material (P = .0019). Therefore, the measurement method is not independent of the restoration material. Differences among groups were observed for IA (P = .0001) and SEM (P = .0013). Significant differences were observed for the Procera (P = .0050) and metal-ceramic (P = .0039) specimen groups when both measurement methods were evaluated separately. Accuracy of fit achieved by the four groups analyzed was within the range of clinical acceptance, yielding Procera Bridge Zirconia to have the best marginal fit using both measurement methods.

The Ills of Marginality: New Perspectives on Health in South Asia.

PubMed

Ecks, Stefan; Sax, William S

2005-12-01

Social marginality and ill health can form an unholy dyad: firstly, groups who suffer from chronic or infectious diseases often find themselves pushed to the margins. Secondly, people who are already on the edge of society tend to suffer more from illness than those at the centre. In development discourse, marginal people are defined as those who are 'not yet' on the same level as the developed mainstream and are in urgent need of aid from the centre. The papers in this special issue take a different approach by insisting that marginality is a radically relational concept: the centre and its margins constitute each other, and the boundaries between them are constantly shifting. The papers show that there are many types of marginality (based on geography, class, caste, sex/gender, ethnicity, etc.), and that each of them has different effects on the health of a particular group. Yet instead of speaking of a plurality of unrelated 'group identities', marginality preserves a sharp sense of unequal power relations between groups. The specific ethnographic contribution to the study of marginality comes from its attention to the point of view of marginal people. This is of critical importance since marginality puts health most under stress when it is clearly and steadily perceived in everyday life. This, in turn, makes it possible to show that living on the margins is not always and everywhere bad for health. While all of the papers present South Asian case studies, the insights and questions are relevant for the study of the ills of marginality in a global perspective.

Time Safety Margin: Theory and Practice

DTIC Science & Technology

2016-09-01

Basic Dive Recovery Terminology The Simplest Definition of TSM: Time Safety Margin is the time to directly travel from the worst-case vector to an...Safety Margin (TSM). TSM is defined as the time in seconds to directly travel from the worst case vector (i.e. worst case combination of parameters...invoked by this AFI, base recovery planning and risk management upon the calculated TSM. TSM is the time in seconds to di- rectly travel from the worst case

Gas hydrates of outer continental margins

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

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 ofmore » 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.« less

Economics of plant production on marginal sites in the state Mecklenburg-Vorpommern

NASA Astrophysics Data System (ADS)

Ziesemer, Andrea; Andreas, Gurgel; Ines, Bull

2017-04-01

Marginal sites are defined by economics. It is not possible to produce any profit there under given conditions of markets and policy even when management is optimized. In the state Mecklenburg-Vorpommern, a portion of nearly 20 % of arable land is characterized by such conditions. There are often to find sandy sites below 28 soil points with low storage capacity and irregular water supply. Animal husbandry as a type of agricultural upgrading has a more important role in the south and southwest of the state than in the regions with better soil quality. The percentage of Maize was already in 2003 twice as high in the regions with more marginal sites. After implementation of the Renewable Energy Act many enterprises started built biogas plants. In 2010, the portion of maize was raised to 20 %. The increase of Maize was combined with a reduction of growing other fodder crops, rye and also by reducing set-aside areas. The scale of the cash crops Rape (16%), Wheat (15 %) and barley (9 %) stayed the same. The yields and production processes of several selected farms in Mecklenburg-Vorpommern were analyzed for the years 2011 to 2016. The farms reached 6.6 tons per hectare of wheat and 6.1 tons per hectare of barley on soils below 28 soil points. Hybrid rye achieved 5.4 tons per hectare and rape 3.0. Maize was especially dependent on water supply and made between 30 and 35 tons per hectare. The big problem in these regions is caused by high production costs in cropping. More than a half of the costs is required for seeds, fertilization and crop protection. However, the remaining revenues are not adequate for paying work and fix costs as an evaluation of farms in Mecklenburg-Vorpommern shows. It is not a valid option to set more land that is arable aside in regions with much marginal sites because cropping is a strategic investment there. Therefore, it is important to make effort on crop rotations and optimization of production intensities to decrease costs per unit and to

30 CFR 204.3 - What alternatives are available for marginal properties?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What alternatives are available for marginal... MINERALS REVENUE MANAGEMENT ALTERNATIVES FOR MARGINAL PROPERTIES General Provisions § 204.3 What alternatives are available for marginal properties? If you have production from a marginal property, MMS and...

Margination of Stiffened Red Blood Cells Regulated By Vessel Geometry.

PubMed

Chen, Yuanyuan; Li, Donghai; Li, Yongjian; Wan, Jiandi; Li, Jiang; Chen, Haosheng

2017-11-10

Margination of stiffened red blood cells has been implicated in many vascular diseases. Here, we report the margination of stiffened RBCs in vivo, and reveal the crucial role of the vessel geometry in the margination by calculations when the blood is seen as viscoelastic fluid. The vessel-geometry-regulated margination is then confirmed by in vitro experiments in microfluidic devices, and it establishes new insights to cell sorting technology and artificial blood vessel fabrication.

Post-breakup faulting of the outer Vøring Margin

NASA Astrophysics Data System (ADS)

Planke, S.; Millett, J.; Jerram, D. A.; Maharjan, D.; Hafeez, A.; Abdelmalak, M. M.; Zastrozhnov, D.; Faleide, J. I.

2017-12-01

Tectonic activity on passive margins may continue for a long time after the main phase of continental breakup. On the southern Vøring Margin, offshore Norway, new high-quality 3D seismic data reveal the presence of extensive normal faults offsetting the Top basalt horizon, along with overlying lower Eocene age sediments. We have completed a detailed seismic interpretation of the new data using a combination of conventional seismic horizon interpretation and igneous seismic geomorphological techniques. The seismic data have been tied to scientific and industry wells to constrain the age of the interpreted horizons and the age and duration of the faulting. The Top basalt horizon displays a dominantly subaerial lava field, on the Vøring Marginal High, with well-defined lava flow morphologies including inflated flow lobes and surface pressure ridges. The prominent kilometer-high Vøring Escarpment was developed when landward flowing lava met the ocean, developing an extensive foreset bedded hyaloclastite delta. Later, a pitted surface was developed in the west during lava emplacement in a wet environment during subsidence of the central rift valley. Earliest Eocene sediments were subsequently deposited on the marginal high. Well-defined northeast trending faults are imaged on the marginal high, cutting across the escarpment. Spacing of the faults is ca. 400-500 m, and offsets are typically of ca. 30-50 m, often defining graben structures. The faults further offset the overlying earliest Eocene sequences in a number of examples. Based on the well ties, faulting mainly took place 5-10 m.y. after continental breakup near the Paleocene-Eocene boundary. Our hypothesis is that the faulting is related to strain partitioning across the developing Vøring Transform Margin. Plate tectonic constraints show that there was an active continent-continent transform in this region also for 10-15 m.y. after breakup. The transform margin is a linear, northwest trending structure, with

Self-Concept Mediates the Relation between Achievement and Emotions in Mathematics

ERIC Educational Resources Information Center

Van der Beek, Jojanneke P. J.; Van der Ven, Sanne H. G.; Kroesbergen, Evelyn H.; Leseman, Paul P. M.

2017-01-01

Background: Mathematics achievement is related to positive and negative emotions. Pekrun's control-value theory of achievement emotions suggests that students' self-concept (i.e., self-appraisal of ability) may be an important mediator of the relation between mathematics achievement and emotions. Aims: The aims were (1) to investigate the…

Role of tumour-free margin distance for loco-regional control in vulvar cancer-a subset analysis of the Arbeitsgemeinschaft Gynäkologische Onkologie CaRE-1 multicenter study.

PubMed

Woelber, Linn; Griebel, Lis-Femke; Eulenburg, Christine; Sehouli, Jalid; Jueckstock, Julia; Hilpert, Felix; de Gregorio, Nikolaus; Hasenburg, Annette; Ignatov, Atanas; Hillemanns, Peter; Fuerst, Sophie; Strauss, Hans-Georg; Baumann, Klaus H; Thiel, Falk C; Mustea, Alexander; Meier, Werner; Harter, Philipp; Wimberger, Pauline; Hanker, Lars Christian; Schmalfeldt, Barbara; Canzler, Ulrich; Fehm, Tanja; Luyten, Alexander; Hellriegel, Martin; Kosse, Jens; Heiss, Christoph; Hantschmann, Peer; Mallmann, Peter; Tanner, Berno; Pfisterer, Jacobus; Richter, Barbara; Neuser, Petra; Mahner, Sven

2016-12-01

A tumour-free pathological resection margin of ≥8 mm is considered state-of-the-art. Available evidence is based on heterogeneous cohorts. This study was designed to clarify the relevance of the resection margin for loco-regional control in vulvar cancer. AGO-CaRE-1 is a large retrospective study. Patients (n = 1618) with vulvar cancer ≥ FIGO stage IB treated at 29 German gynecologic-cancer-centres 1998-2008 were included. This subgroup analysis focuses on solely surgically treated node-negative patients with complete tumour resection (n = 289). Of the 289 analysed patients, 141 (48.8%) had pT1b, 140 (48.4%) pT2 and 8 (2.8%) pT3 tumours. One hundred twenty-five (43.3%) underwent complete vulvectomy, 127 (43.9%) partial vulvectomy and 37 (12.8%) radical local excision. The median minimal resection margin was 5 mm (1 mm-33 mm); all patients received groin staging, in 86.5% with full dissection. Median follow-up was 35.1 months. 46 (15.9%) patients developed recurrence, thereof 34 (11.8%) at the vulva, after a median of 18.3 months. Vulvar recurrence rates were 12.6% in patients with a margin <8 mm and 10.2% in patients with a margin ≥8 mm. When analysed as a continuous variable, the margin distance had no statistically significant impact on local recurrence (HR per mm increase: 0.930, 95% CI: 0.849-1.020; p = 0.125). Multivariate analyses did also not reveal a significant association between the margin and local recurrence neither when analysed as continuous variable nor categorically based on the 8 mm cutoff. Results were consistent when looking at disease-free-survival and time-to-recurrence at any site (HR per mm increase: 0.949, 95% CI: 0.864-1.041; p = 0.267). The need for a minimal margin of 8 mm could not be confirmed in the large and homogeneous node-negative cohort of the AGO-CaRE database. Copyright © 2016 Elsevier Ltd. All rights reserved.

Adolescent Mental Health, Behavior Problems, and Academic Achievement

PubMed Central

McLeod, Jane D.; Uemura, Ryotaro; Rohrman, Shawna

2013-01-01

Prior research on the association of mental health and behavior problems with academic achievement is limited because it does not consider multiple problems simultaneously, take co-occurring problems into account, and control for academic aptitude. We addressed these limitations using data from the National Longitudinal Study of Adolescent Health (N = 6,315). We estimated the associations of depression, attention problems, delinquency, and substance use with two indicators of academic achievement (high school GPA and highest degree received) with controls for academic aptitude. Attention problems, delinquency, and substance use were significantly associated with diminished achievement, but depression was not. Combinations of problems involving substance use were especially consequential. Our results demonstrate that the social consequences of mental health problems are not the inevitable result of diminished functional ability but, rather, reflect negative social responses. These results also encourage a broader perspective on mental health by demonstrating that behavior problems heighten the negative consequences of more traditional forms of distress. PMID:23197485

In vitro marginal fit of three all-ceramic crown systems.

PubMed

Yeo, In-Sung; Yang, Jae-Ho; Lee, Jai-Bong

2003-11-01

Studies on marginal discrepancies of single restorations using various systems and materials have resulted in statistical inferences that are ambiguous because of small sample sizes and limited numbers of measurements per specimen. The purpose of this study was to compare the marginal adaptation of single anterior restorations made using different systems. The in vitro marginal discrepancies of 3 different all-ceramic crown systems (Celay In-Ceram, conventional In-Ceram, and IPS Empress 2 layering technique), and a control group of metal ceramic restorations were evaluated and compared by measuring the gap dimension between the crowns and the prepared tooth at the marginal opening. The crowns were made for 1 extracted maxillary central incisor prepared with a 1-mm shoulder margin and 6-degree tapered walls by milling. Thirty crowns per system were fabricated. Crown measurements were recorded with an optical microscope, with an accuracy of +/-0.1 microm, at 50 points spaced approximately 400 microm along the circumferential margin. The criterion of 120 microm was used as the maximum clinically acceptable marginal gap. Mean gap dimensions and standard deviations were calculated for marginal opening. The data were analyzed with a 1-way analysis of variance (alpha=.05). Mean gap dimensions and standard deviations at the marginal opening for the incisor crowns were 87 +/- 34 microm for control, 83 +/- 33 microm for Celay In-Ceram, 112 +/- 55 microm for conventional In-Ceram, and 46 +/- 16 microm for the IPS Empress 2 layering technique. Significant differences were found among the crown groups (P<.05). Compared with the control group, the IPS Empress 2 group had significantly smaller marginal discrepancies (P<.05), and the conventional In-Ceram group exhibited significantly greater marginal discrepancies (P<.05). There was no significant difference between the Celay In-Ceram and the control group. Within the limitations of this study, the marginal discrepancies were all

Identifying technology innovations for marginalized smallholders-A conceptual approach.

PubMed

Malek, Mohammad Abdul; Gatzweiler, Franz W; Von Braun, Joachim

2017-05-01

This paper adds a contribution in the existing literature in terms of theoretical and conceptual background for the identification of idle potentials of marginal rural areas and people by means of technological and institutional innovations. The approach follows ex-ante assessment for identifying suitable technology and institutional innovations for marginalized smallholders in marginal areas-divided into three main parts (mapping, surveying and evaluating) and several steps. Finally, it contributes to the inclusion of marginalized smallholders by an improved way of understanding the interactions between technology needs, farming systems, ecological resources and poverty characteristics in the different segments of the poor, and to link these insights with productivity enhancing technologies.

Sedimentary Flux to Passive Margins From Inversion of Drainage Patterns: Examples from Africa

NASA Astrophysics Data System (ADS)

Lodhia, Bhavik Harish; Roberts, Gareth G.; Fraser, Alastair

2017-04-01

-loaded subsidence that cannot be attributed to extension, thermal subsidence, salt-tectonics or glacio-eustasy. Stratigraphy mapped across the margin shows that this anomalous subsidence affected an area larger than 500 by 500 km. We suggest that this anomalous subsidence was caused by Neogene dynamic drawdown. Conversion of the Schaeffer & Lebedev (2013) velocity model to temperature and simple isostatic calculations indicate that negative buoyancy anomalies directly beneath the Mauritanian margin generate up to 500 m of drawdown today. Measured ocean-age depth residuals and calculated subsidence histories suggest that dynamic uplift of the Cape Verde swell and dynamic drawdown in the east generated a gradient in dynamic support during the last 25 Ma.

Analysis of System Margins on Missions Utilizing Solar Electric Propulsion

NASA Technical Reports Server (NTRS)

Oh, David Y.; Landau, Damon; Randolph, Thomas; Timmerman, Paul; Chase, James; Sims, Jon; Kowalkowski, Theresa

2008-01-01

NASA's Jet Propulsion Laboratory has conducted a study focused on the analysis of appropriate margins for deep space missions using solar electric propulsion (SEP). The purpose of this study is to understand the links between disparate system margins (power, mass, thermal, etc.) and their impact on overall mission performance and robustness. It is determined that the various sources of uncertainty and risk associated with electric propulsion mission design can be summarized into three relatively independent parameters 1) EP Power Margin, 2) Propellant Margin and 3) Duty Cycle Margin. The overall relationship between these parameters and other major sources of uncertainty is presented. A detailed trajectory analysis is conducted to examine the impact that various assumptions related to power, duty cycle, destination, and thruster performance including missed thrust periods have on overall performance. Recommendations are presented for system margins for deep space missions utilizing solar electric propulsion.

IS NSVS 5066754 A NEAR-CONTACT OR A MARGINAL CONTACT BINARY?

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

Samec, Ronald G.; Nyaude, Ropafadzo; Caton, Daniel B.

BVR{sub cIc} light curves of NSVS 5066754 were taken on 2014 May at Dark Sky Observatory in North Carolina. This variable is a solar-type eclipsing binary ( T 1 ∼ 5750 K) with a period of only 0.3751689(1) days. It appeared to be one of the shortest periods in Shaw’s list of near-contact binaries. The Binary Maker fits and our Wilson–Devinney solutions show that the binary could have both semidetached and marginal contact binary configurations. Five new times of minimum light were calculated, along with two minima determined from archived All Sky Automated Survey observations. From these minima and the discovery epoch, amore » quadratic ephemeris was determined. Thus, a magnetic braking scenario is possible. Both semidetached and contact models were explored. A marginal contact solution had the best sum of square residuals. It gave a mass ratio of ∼0.5, and a component temperature difference of ∼360 K, albeit somewhat large for a contact binary. Two substantial cool spots were determined in this solution with 37° and 28° radii and t-factors or 0.94 and 0.78 respectively. The fill-out is very shallow, ∼106%. It may have recently achieved contact.« less

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.

Extranodal Marginal Zone Lymphoma: No Longer Just a Sidekick.

PubMed

Kamdar, Manali K; Smith, Sonali M

2017-06-10

The Oncology Grand Rounds series is designed to place original reports published in the Journal into clinical context. A case presentation is followed by a description of diagnostic and management challenges, a review of the relevant literature, and a summary of the authors' suggested management approaches. The goal of this series is to help readers better understand how to apply the results of key studies, including those published in Journal of Clinical Oncology, to patients seen in their own clinical practice. A 51-year-old healthy female with good performance status presented for gynecologic surgery for a benign condition. A preprocedure chest x-ray showed a right lower lobe infiltrate. A subsequent computed tomography (CT) scan of the chest with contrast revealed a large consolidative right lower lobe mass with surrounding inflammation ( Fig 1A ). Bronchoscopy with biopsy revealed a low-grade lymphoma with the following immunophenotype: CD45 + , CD20 + , BCL2 + , CD10 negative, CD5 negative, cyclin D1 negative, and Ki-67 index of less than 5%. Morphology and immunohistochemistry were most consistent with pulmonary extranodal marginal zone lymphoma (ENMZL; Fig 2 ). The patient was asymptomatic and denied fevers, sweats, weight loss, shortness of breath or dyspnea on exertion, or cough. Her history was notable for exposure to parrots over several months before presentation. Complete staging with a CT of the chest, abdomen, and pelvis with contrast redemonstrated disease that was localized to the chest with mild compression of the pulmonary vasculature but no other evidence of lymphoma. She was referred to discuss management of stage I AE pulmonary ENMZL lymphoma.

Prediction of large negative shaded-side spacecraft potentials

NASA Technical Reports Server (NTRS)

Prokopenko, S. M. L.; Laframboise, J. G.

1977-01-01

A calculation by Knott, for the floating potential of a spherically symmetric synchronous-altitude satellite in eclipse, was adapted to provide simple calculations of upper bounds on negative potentials which may be achieved by electrically isolated shaded surfaces on spacecraft in sunlight. Large (approximately 60 percent) increases in predicted negative shaded-side potentials are obtained. To investigate effective potential barrier or angular momentum selection effects due to the presence of less negative sunlit-side or adjacent surface potentials, these expressions were replaced by the ion random current, which is a lower bound for convex surfaces when such effects become very severe. Further large increases in predicted negative potentials were obtained, amounting to a doubling in some cases.

Stroke: a Hidden Danger of Margin Trading in Stock Markets.

PubMed

Lin, Shu-Hui; Wang, Chien-Ho; Liu, Tsai-Ching; Chen, Chin-Shyan

2015-10-01

Using 10-year population data from 2000 through 2009 in Taiwan, this is the first paper to analyze the relationship between margin trading in stock markets and stroke hospitalizations. The results show that 3 and 6 days after an increase of margin trading in the Taiwan stock markets are associated with greater stoke hospitalizations. In general, a 1 % increase in total margin trading positions is associated with an increment of 2.5 in the total number of stroke hospitalizations, where the mean number of hospital admissions is 233 cases a day. We further examine the effects of margin trading by gender and age groups and find that the effects of margin trading are significant for males and those who are 45-74 years old only. In summary, buying stocks with money you do not have is quite risky, especially if the prices of those stocks fall past a certain level or if there is a sudden and severe drop in the stock market. There is also a hidden danger to one's health from margin trading. A person should be cautious before conducting margin trading, because while it can be quite profitable, danger always lurks just around the corner.

Uplift history of a transform continental margin revealed by the stratigraphic record: The case of the Agulhas transform margin along the Southern African Plateau

NASA Astrophysics Data System (ADS)

Baby, Guillaume; Guillocheau, François; Boulogne, Carl; Robin, Cécile; Dall'Asta, Massimo

2018-04-01

The south and southeast coast of southern Africa (from 28°S to 33°S) forms a high-elevated transform passive margin bounded to the east by the Agulhas-Falkland Fracture Zone (AFFZ). We analysed the stratigraphic record of the Outeniqua and Durban (Thekwini) Basins, located on the African side of the AFFZ, to determine the evolution of these margins from the rifting stage to present-day. The goal was to reconstruct the strike-slip evolution of the Agulhas Margin and the uplift of the inland high-elevation South African Plateau. The Agulhas transform passive margin results from four successive stages: Rifting stage, from Late Triassic to Early Cretaceous ( 200?-134 Ma), punctuated by three successive rifting episodes related to the Gondwana breakup; Wrench stage (134-131 Ma), evidenced by strike- and dip-slip deformations increasing toward the AFFZ; Active transform margin stage (131-92 Ma), during which the Falkland/Malvinas Plateau drifts away along the AFFZ, with an uplift of the northeastern part of the Outeniqua Basin progressively migrating toward the west; Thermal subsidence stage (92-0 Ma), marked by a major change in the configuration of the margin (onset of the shelf-break passive margin morphology). Two main periods of uplift were documented during the thermal subsidence stage of the Agulhas Margin: (1) a 92 Ma short-lived margin-scale uplift, followed by a second one at 76 Ma located along the Outeniqua Basin and; (2) a long-lasting uplift from 40 to 15 Ma limited to the Durban (Thekwini) Basin. This suggests that the South African Plateau is an old Upper Cretaceous relief (90-70 Ma) reactivated during Late Eocene to Early Miocene times (40-15 Ma).

The Ebro margin study, northwestern Mediterranean Sea - an introduction

USGS Publications Warehouse

Maldonado, A.; Hans, Nelson C.

1990-01-01

The Ebro continental margin from the coast to the deep sea off northeastern Spain was selected for a multidisciplinary project because of the abundant Ebro River sediment supply, Pliocene and Quaternary progradation, and margin development in a restricted basin where a variety of controlling factors could be evaluated. The nature of this young passive margin for the last 5 m.y. was investigated with particular emphasis on marine circulation, sediment dynamics, sediment geochemistry, depositional facies, seismic stratigraphy, geotechnical properties, geological hazards and human influences. These studies show the importance of marine circulation, variation in sediment supply, sea-level oscillation and tectonic setting for the understanding of modern and ancient margin depositional processes and growth patterns. ?? 1990.

Marginal oil fields, profitable oil at low reserves: How?

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

Agiza, M.N.; Shaheen, S.E.; Barawi, S.A.

1995-12-31

Fields with recoverable reserves of about five million barrels of oil are considered in Egypt as marginal fields. Economics of Egyptian marginal oil fields depend on non-traditional approaches followed in developing and operating such fields. The actual exploration, development and operating expenses and state fiscal terms were used to evaluate the sensitivity of the economic parameters of such marginal fields. The operator net present value (NPV) and internal rate of return (IRR) beside the government take are presented for different parameters used. The purpose is to make acceptable profits out of the marginal oil fields, for the mutual benefits ofmore » both the country and the investors.« less

Society of Surgical Oncology–American Society for Radiation Oncology Consensus Guideline on Margins for Breast-Conserving Surgery With Whole-Breast Irradiation in Stages I and II Invasive Breast Cancer

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

Moran, Meena S.; Schnitt, Stuart J.; Giuliano, Armando E.

Purpose: To convene a multidisciplinary panel of breast experts to examine the relationship between margin width and ipsilateral breast tumor recurrence (IBTR) and develop a guideline for defining adequate margins in the setting of breast conserving surgery and adjuvant radiation therapy. Methods and Materials: A multidisciplinary consensus panel used a meta-analysis of margin width and IBTR from a systematic review of 33 studies including 28,162 patients as the primary evidence base for consensus. Results: Positive margins (ink on invasive carcinoma or ductal carcinoma in situ) are associated with a 2-fold increase in the risk of IBTR compared with negative margins.more » This increased risk is not mitigated by favorable biology, endocrine therapy, or a radiation boost. More widely clear margins than no ink on tumor do not significantly decrease the rate of IBTR compared with no ink on tumor. There is no evidence that more widely clear margins reduce IBTR for young patients or for those with unfavorable biology, lobular cancers, or cancers with an extensive intraductal component. Conclusions: The use of no ink on tumor as the standard for an adequate margin in invasive cancer in the era of multidisciplinary therapy is associated with low rates of IBTR and has the potential to decrease re-excision rates, improve cosmetic outcomes, and decrease health care costs.« less

Extensional fault geometry and its flexural isostatic response during the formation of the Iberia - Newfoundland conjugate rifted margins

NASA Astrophysics Data System (ADS)

Gómez-Romeu, Júlia; Kusznir, Nick; Manatschal, Gianreto; Roberts, Alan

2017-04-01

Despite magma-poor rifted margins having been extensively studied for the last 20 years, the evolution of extensional fault geometry and the flexural isostatic response to faulting remain still debated topics. We investigate how the flexural isostatic response to faulting controls the structural development of the distal part of rifted margins in the hyper-extended domain and the resulting sedimentary record. In particular we address an important question concerning the geometry and evolution of extensional faults within distal hyper-extended continental crust; are the seismically observed extensional fault blocks in this region allochthons from the upper plate or are they autochthons of the lower plate? In order to achieve our aim we focus on the west Iberian rifted continental margin along the TGS and LG12 seismic profiles. Our strategy is to use a kinematic forward model (RIFTER) to model the tectonic and stratigraphic development of the west Iberia margin along TGS-LG12 and quantitatively test and calibrate the model against breakup paleo-bathymetry, crustal basement thickness and well data. RIFTER incorporates the flexural isostatic response to extensional faulting, crustal thinning, lithosphere thermal loads, sedimentation and erosion. The model predicts the structural and stratigraphic consequences of recursive sequential faulting and sedimentation. The target data used to constrain model predictions consists of two components: (i) gravity anomaly inversion is used to determine Moho depth, crustal basement thickness and continental lithosphere thinning and (ii) reverse post-rift subsidence modelling consisting of flexural backstripping, decompaction and reverse post-rift thermal subsidence modelling is used to give paleo-bathymetry at breakup time. We show that successful modelling of the structural and stratigraphic development of the TGS-LG12 Iberian margin transect also requires the simultaneous modelling of the Newfoundland conjugate margin, which we

Margins in extra-abdominal desmoid tumors: a comparative analysis.

PubMed

Leithner, Andreas; Gapp, Markus; Leithner, Katharina; Radl, Roman; Krippl, Peter; Beham, Alfred; Windhager, Reinhard

2004-06-01

The main treatment of extra-abdominal desmoid tumors remains surgery, but recurrence rates up to 80% are reported. The impact of microscopic surgical margin status according to the Enneking classification system is discussed controversially. Therefore, the authors screened the published literature for reliable data on the importance of a wide or radical excision of extra-abdominal desmoid tumors. All studies with more than ten patients, a surgical treatment only, and margin status stated were included. Only 12 out of 49 identified studies fulfilled the inclusion criteria. One hundred fifty-two primary tumors were excised with wide or radical microscopic surgical margins, while in 260 cases a marginal or intralesional excision was performed. In the first group 41 patients (27%) and in the second one 187 patients (72%) developed a recurrence. Therefore, microscopic surgical margin status according to the Enneking classification system is a significant prognostic factor (P < 0.001). The data of this review underline the strategy of a wide or radical local excision as the treatment of choice. Furthermore, as a large number of studies had to be excluded from this analysis, exact microscopic surgical margin status should be provided in future studies in order to allow comparability. . Copyright 2004 Wiley-Liss, Inc.

Volcanic passive margins: another way to break up continents

PubMed Central

Geoffroy, L.; Burov, E. B.; Werner, P.

2015-01-01

Two major types of passive margins are recognized, i.e. volcanic and non-volcanic, without proposing distinctive mechanisms for their formation. Volcanic passive margins are associated with the extrusion and intrusion of large volumes of magma, predominantly mafic, and represent distinctive features of Larges Igneous Provinces, in which regional fissural volcanism predates localized syn-magmatic break-up of the lithosphere. In contrast with non-volcanic margins, continentward-dipping detachment faults accommodate crustal necking at both conjugate volcanic margins. These faults root on a two-layer deformed ductile crust that appears to be partly of igneous nature. This lower crust is exhumed up to the bottom of the syn-extension extrusives at the outer parts of the margin. Our numerical modelling suggests that strengthening of deep continental crust during early magmatic stages provokes a divergent flow of the ductile lithosphere away from a central continental block, which becomes thinner with time due to the flow-induced mechanical erosion acting at its base. Crustal-scale faults dipping continentward are rooted over this flowing material, thus isolating micro-continents within the future oceanic domain. Pure-shear type deformation affects the bulk lithosphere at VPMs until continental breakup, and the geometry of the margin is closely related to the dynamics of an active and melting mantle. PMID:26442807

Volcanic passive margins: another way to break up continents.

PubMed

Geoffroy, L; Burov, E B; Werner, P

2015-10-07

Two major types of passive margins are recognized, i.e. volcanic and non-volcanic, without proposing distinctive mechanisms for their formation. Volcanic passive margins are associated with the extrusion and intrusion of large volumes of magma, predominantly mafic, and represent distinctive features of Larges Igneous Provinces, in which regional fissural volcanism predates localized syn-magmatic break-up of the lithosphere. In contrast with non-volcanic margins, continentward-dipping detachment faults accommodate crustal necking at both conjugate volcanic margins. These faults root on a two-layer deformed ductile crust that appears to be partly of igneous nature. This lower crust is exhumed up to the bottom of the syn-extension extrusives at the outer parts of the margin. Our numerical modelling suggests that strengthening of deep continental crust during early magmatic stages provokes a divergent flow of the ductile lithosphere away from a central continental block, which becomes thinner with time due to the flow-induced mechanical erosion acting at its base. Crustal-scale faults dipping continentward are rooted over this flowing material, thus isolating micro-continents within the future oceanic domain. Pure-shear type deformation affects the bulk lithosphere at VPMs until continental breakup, and the geometry of the margin is closely related to the dynamics of an active and melting mantle.

NF-κB deregulation in splenic marginal zone lymphoma.

PubMed

Spina, Valeria; Rossi, Davide

2016-08-01

Splenic marginal zone lymphoma is a rare mature B-cell malignancy involving the spleen, bone marrow and blood. Over the past years, the rapid expansion of sequencing technologies allowing the genome-wide assessment of genomic, epigenetic and transcriptional changes has revolutionized our understanding of the biological basis of splenic marginal zone lymphoma by providing a comprehensive and unbiased view of the genes/pathways that are deregulated in this disease. NF-κB is a family of transcription factors that plays critical roles in development, survival, and activation of B lymphocytes. Consistent with the physiological involvement of NF-κB signalling in proliferation and commitment of mature B-cells to the marginal zone of the spleen, many oncogenic mutations involved in constitutive activation of the NF-κB pathway were recently identified in splenic marginal zone lymphoma. This review describes the progress in understanding the mechanism of NF-κB activation in splenic marginal zone lymphoma, including molecular, epigenetic and post-transcriptional modifications of NF-κB genes and of upstream pathways, and discusses how information gained from these efforts has provided new insights on potential targets of diagnostic, prognostic and therapeutic relevance for splenic marginal zone lymphoma. Copyright © 2016. Published by Elsevier Ltd.

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)

Short (≤ 1 mm) positive surgical margin and risk of biochemical recurrence after radical prostatectomy.

PubMed

Shikanov, Sergey; Marchetti, Pablo; Desai, Vikas; Razmaria, Aria; Antic, Tatjana; Al-Ahmadie, Hikmat; Zagaja, Gregory; Eggener, Scott; Brendler, Charles; Shalhav, Arieh

2013-04-01

WHAT'S KNOWN ON THE SUBJECT? AND WHAT DOES THE STUDY ADD?: It has been suggested that a very short positive margin does not confer additional risk of BCR after radical prostatectomy. This study shows that even very short PSM is associated with increased risk of BCR. To re-evaluate, in a larger cohort with longer follow-up, our previously reported finding that a positive surgical margin (PSM) ≤ 1 mm may not confer an additional risk for biochemical recurrence (BCR) compared with a negative surgical margin (NSM). Margin status and length were evaluated in 2866 men treated with radical prostatectomy (RP) for clinically localized prostate cancer at our institution from 1994 to 2009. We compared the BCR-free survival probability of men with NSMs, a PSM ≤ 1 mm, and a PSM < 1 mm using the Kaplan-Meier method and a Cox regression model adjusted for preoperative prostate-specific antigen (PSA) level, age, pathological stage and pathological Gleason score (GS). Compared with a NSM, a PSM ≤ 1 mm was associated with 17% lower 3-year BCR-free survival for men with pT3 and GS ≥ 7 tumours and a 6% lower 3-year BCR-free survival for men with pT2 and GS ≤ 6 tumours (log-rank P < 0.001 for all). In the multivariate model, a PSM ≤ 1 mm was associated with a probability of BCR twice as high as that for a NSM (hazard ratio [HR] 2.2), as were a higher PSA level (HR 1.04), higher pathological stage (HR 2.7) and higher pathological GS (HR 3.7 [all P < 0.001]). In men with non-organ-confined or high grade prostate cancer, a PSM ≤ 1 mm has a significant adverse impact on BCR rates. © 2012 The Authors. BJU International © 2012 BJU International.

Immunohistochemical analysis of the novel marginal zone B-cell marker IRTA1 in malignant lymphoma.

PubMed

Ikeda, Jun-Ichiro; Kohara, Masaharu; Tsuruta, Yoko; Nojima, Satoshi; Tahara, Shinichiro; Ohshima, Kenji; Kurashige, Masako; Wada, Naoki; Morii, Eiichi

2017-01-01

Marginal zone lymphoma (MZL) is a low-grade B-cell lymphoma derived from marginal zone B cells. Because of a lack of specific immunohistochemical markers, MZL is mainly diagnosed based on the cytological appearance and growth pattern of the tumor. Marginal zone B cells were recently shown to selectively express immunoglobulin superfamily receptor translocation-associated 1 (IRTA1), but the antibody used in that study is not commercially available. We therefore investigated the IRTA1 expression in nonneoplastic lymphoid tissues and 261 malignant lymphomas, examining the ability of a commercially available antibody to accurately diagnose MZL. Among 37 MZLs, 23 of 25 extranodal MZLs of mucosa-associated lymphoid tissue (MALT lymphomas), 3 of 6 splenic MZLs and 3 of 6 nodal MZLs were positive for IRTA1. Among the 98 diffuse large B-cell lymphomas, 33 were positive for IRTA1, including 1 of 38 follicular lymphomas, and all precursor B-lymphoblastic (2/2) and T-lymphoblastic (7/7) leukemia/lymphomas. Other mature B-cell and T-cell lymphomas, and Hodgkin lymphoma were negative for IRTA1. In MALT lymphoma, positive cells were detected mainly in intraepithelial and subepithelial marginal zone B cells. In 1 case of grade 3 follicular lymphoma, IRTA1 was also expressed in the area of large cell transformation. When tumors were classified as germinal center B cell-like (GCB) or non-GCB using the algorithm of Hans, positive expression of IRTA1 was correlated significantly with non-GCB diffuse large B-cell lymphomas (P < .05). These results demonstrated the ability of the commercially available IRTA1 antibody to distinguish MALT lymphoma from other low-grade B-cell lymphomas. Copyright © 2016 Elsevier Inc. All rights reserved.

[Banff score changes in kidneys from marginal donors].

PubMed

Borda, Bernadett; Szederkényi, Edit; Ottlakán, Aurél; Kemény, Éva; Szabó, Viktor; Hódi, Zoltán; Lázár, György

2016-02-21

Despite an increase in the number of cadaver donors and the number of overall organ transplantations, the dramatic increase in the waiting list makes it necessary to reconsider donor criteria. The authors examined whether differences could exist in the function and/or morphology of transplanted kidneys originated from marginal and ideal donors one and five years after transplantation. Kidney function and histopathologic findings were analysed and compared one and 5 years after transplantation in 97 patients having marginal donor kidneys and 178 patients who received ideal donor kidneys. Serum creatinine level was significantly higher (p = 0.0001) and estimated glomerular filtration rate was significantly lower (p = 0.003) in patients having marginal donor kidneys as compared to those with ideal donor kidneys 5 years after transplantation. Morphological changes in the transplanted kidneys such as tubulitis (p = 0.014) and interstitial inflammation (p = 0.025) were significantly more frequently present in patients with marginal donor kidneys than in those with ideal donor kidneys one year after transplantation. Despite an absence of differences in kidney function one year after kidney transplantation between patients having marginal and ideal donor kidneys, morphologic differences in the transplanted kidneys can be detected between the two groups of patients.

Influence of Different Ceramic Systems on Marginal Misfit.

PubMed

Vargas, S P; Neves, A C C; Vitti, R; Amaral, M; Henrique, M N; Silva-Concílio, L R

2017-09-01

the aim of this study was to evaluate the marginal misfit at the interface between a ceramic coping and its abutment. Twenty-four specimens were made with solid abutments. The specimens were divided into 3 groups according to the ceramic system (n = 8): Lava (zirconia), IPS e.max Press (lithium disilicate), and IPS Empress Esthetic (leucite). All copings were cemented with resin luting agent (RelyX U200) and the marginal misfit were evaluated at 3 different times: initial, after cementation, and after mechanical cycling using a linear measuring microscope (Measuring Microscope STM-Olympus) at a magnification of 40x. All specimens were subjected to mechanical cycling (1 million cycles) by an universal testing machine (Instron 8800). The results were statistically analyzed using Analysis of Variance and Student's t-test (α = 0.05). all groups showed an increase in the marginal misfit after cementation. The lithium disilicate group demonstrated the lowest interacial gap values at each evaluation (p = 0.001). The zirconia and leucite groups showed similar interfacial gap values (initial, p = 0.244; and post cementation, p = 0.751). the cementation increase the marginal misfit, but the mechanical cycling did not influence the marginal misfit of the ceramics systems evaluated. Copyright© 2017 Dennis Barber Ltd.

Subjective Well-Being, Test Anxiety, Academic Achievement: Testing for Reciprocal Effects.

PubMed

Steinmayr, Ricarda; Crede, Julia; McElvany, Nele; Wirthwein, Linda

2015-01-01

In the context of adolescents' subjective well-being (SWB), research has recently focused on a number of different school variables. The direction of the relationships between adolescents' SWB, academic achievement, and test anxiety is, however, still open although reciprocal causation has been hypothesized. The present study set out to investigate to what extent SWB, academic achievement, and test anxiety influence each other over time. A sample of N = 290 11th grade students (n = 138 female; age: M = 16.54 years, SD = 0.57) completed measures of SWB and test anxiety in the time span of 1 year. Grade point average (GPA) indicated students' academic achievement. We analyzed the reciprocal relations using cross-lagged structural equation modeling. The model fit was satisfactory for all computed models. Results indicated that the worry component of test anxiety negatively and GPA positively predicted changes in the cognitive component of SWB (life satisfaction). Worry also negatively predicted changes in the affective component of SWB. Moreover, worry negatively predicted changes in students' GPA. Directions for future research and the differential predictive influences of academic achievement and test anxiety on adolescents' SWB are discussed with regard to potential underlying processes.

Subjective Well-Being, Test Anxiety, Academic Achievement: Testing for Reciprocal Effects

PubMed Central

Steinmayr, Ricarda; Crede, Julia; McElvany, Nele; Wirthwein, Linda

2016-01-01

In the context of adolescents’ subjective well-being (SWB), research has recently focused on a number of different school variables. The direction of the relationships between adolescents’ SWB, academic achievement, and test anxiety is, however, still open although reciprocal causation has been hypothesized. The present study set out to investigate to what extent SWB, academic achievement, and test anxiety influence each other over time. A sample of N = 290 11th grade students (n = 138 female; age: M = 16.54 years, SD = 0.57) completed measures of SWB and test anxiety in the time span of 1 year. Grade point average (GPA) indicated students’ academic achievement. We analyzed the reciprocal relations using cross-lagged structural equation modeling. The model fit was satisfactory for all computed models. Results indicated that the worry component of test anxiety negatively and GPA positively predicted changes in the cognitive component of SWB (life satisfaction). Worry also negatively predicted changes in the affective component of SWB. Moreover, worry negatively predicted changes in students’ GPA. Directions for future research and the differential predictive influences of academic achievement and test anxiety on adolescents’ SWB are discussed with regard to potential underlying processes. PMID:26779096

37 CFR 1.52 - Language, paper, writing, margins, compact disc specifications.

Code of Federal Regulations, 2010 CFR

2010-07-01

... cm (3/4 inch), a left side margin of at least 2.5 cm (1 inch), a right side margin of at least 2.0 cm... brackets should appear to the right of the left margin as the first item in each paragraph, before the... elements, and should not be independently numbered. If a nontext element extends to the left margin, it...

Study of a safety margin system for powered-lift STOL aircraft

NASA Technical Reports Server (NTRS)

Heffley, R. K.; Jewell, W. F.

1978-01-01

A study was conducted to explore the feasibility of a safety margin system for powered-lift aircraft which require a backside piloting technique. The objective of the safety margin system was to present multiple safety margin criteria as a single variable which could be tracked manually or automatically and which could be monitored for the purpose of deriving safety margin status. The study involved a pilot-in-the-loop analysis of several safety margin system concepts and a simulation experiment to evaluate those concepts which showed promise of providing a good solution. A system was ultimately configured which offered reasonable compromises in controllability, status information content, and the ability to regulate the safety margin at some expense of the allowable low speed flight path envelope.

Supervised linear dimensionality reduction with robust margins for object recognition

NASA Astrophysics Data System (ADS)

Dornaika, F.; Assoum, A.

2013-01-01

Linear Dimensionality Reduction (LDR) techniques have been increasingly important in computer vision and pattern recognition since they permit a relatively simple mapping of data onto a lower dimensional subspace, leading to simple and computationally efficient classification strategies. Recently, many linear discriminant methods have been developed in order to reduce the dimensionality of visual data and to enhance the discrimination between different groups or classes. Many existing linear embedding techniques relied on the use of local margins in order to get a good discrimination performance. However, dealing with outliers and within-class diversity has not been addressed by margin-based embedding method. In this paper, we explored the use of different margin-based linear embedding methods. More precisely, we propose to use the concepts of Median miss and Median hit for building robust margin-based criteria. Based on such margins, we seek the projection directions (linear embedding) such that the sum of local margins is maximized. Our proposed approach has been applied to the problem of appearance-based face recognition. Experiments performed on four public face databases show that the proposed approach can give better generalization performance than the classic Average Neighborhood Margin Maximization (ANMM). Moreover, thanks to the use of robust margins, the proposed method down-grades gracefully when label outliers contaminate the training data set. In particular, we show that the concept of Median hit was crucial in order to get robust performance in the presence of outliers.

Fabrication of a micromold using negative PMER

NASA Astrophysics Data System (ADS)

Kwon, Young A.; Chae, Kyoung-Soo; Jeoung, Dae S.; Kim, Jong Y.; Moon, Sung

2001-10-01

We fabricated a micro mold using UV-lithography process with a novel mold material, negative PMER. Negative PMER(TOK, PMER N-CA3000) is a chemically amplified negative tone photoresist on a novolak resin base. It can be processed using standard equipment such as standard spin coater, baking with ovens or hotplates, and immersion development tools. Good quality resist patterns of up to 36μm thickness were achieved by means of this equipment in a short time. The conditions of this process were pre-exposure bake of 110 degree(s)C/12min, exposure dose of 675mJ/cm2 post-exposure bake of 100 degree(s)C/9min, and development for 10min.

Marginal adaptation of composite resins under two adhesive techniques.

PubMed

Dačić, Stefan; Veselinović, Aleksandar M; Mitić, Aleksandar; Nikolić, Marija; Cenić, Milica; Dačić-Simonović, Dragica

2016-11-01

In the present research, different adhesive techniques were used to set up fillings with composite resins. After the application of etch and rinse or self etch adhesive technique, marginal adaptation of composite fillings was estimated by the length of margins without gaps, and by the microretention of resin in enamel and dentin. The study material consisted of 40 extracted teeth. Twenty Class V cavities were treated with 35% phosphorous acid and restored after rinsing by Adper Single Bond 2 and Filtek Ultimate-ASB/FU 3M ESPE composite system. The remaining 20 cavities were restored by Adper Easy One-AEO/FU 3M ESPE composite system. Marginal adaptation of composite fillings was examined using a scanning electron microscope (SEM). The etch and rinse adhesive technique showed a significantly higher percentage of margin length without gaps (in enamel: 92.5%, in dentin: 57.3%), compared with the self-etch technique with lower percentage of margin length without gaps, in enamel 70.4% (p < .001), and in dentin-22.6% (p < .05). In the first technique, microretention was composed of adhesive and hybrid layers as well as resin tugs in interprismatic spaces of enamel, while the dentin microretention was composed of adhesive and hybrid layers with resin tugs in dentin canals. In the second technique, resin tugs were rarely seen and a microgap was dominant along the border of restoration margins. The SEM analysis showed a better marginal adaptation of composite resin to enamel and dentin with better microretention when the etch and rinse adhesive procedure was applied. © 2016 Wiley Periodicals, Inc.

Influence of margin segmentation and anomalous volcanism upon the break-up of the Hatton Bank rifted margin, west of the UK

NASA Astrophysics Data System (ADS)

Elliott, G. M.; Parson, L. M.

2007-12-01

The Hatton Bank margin, flanking the Iceland Basin is a widely cited example of a volcanic rifted margin. Prior to this study insights into the break-up history of the margin have been limited to profiles in the north and south, yet whilst valuable, the along margin tectono-magmatic variability has not been revealed. Over 5660 line km of high quality reflection seismic profiles with supplementary multibeam bathymetry were collected to support the UK's claim to Hatton region under the United Nations Convention on Law of the Sea (UNCLOS). Integration of this new data with existing profiles, allowed the margin to be divided into three segments, each of which are flanked by oceanic crust with a smooth upper surface and internal dipping reflectors. The southernmost segment is characterised by a series of inner and outer seaward dipping reflector (SDR) packages, which are separated by an outer high feature. The outer SDR are truncated by Endymion Spur, a chain of steep sided, late stage volcanic cones linked with necks. The central sector has no inner SDR package and is characterised by the presence of a highly intruded continental block, the Hatton Bank Block (HBB). The northern sector is adjacent to Lousy Bank, with a wider region of SDR recognised than to the south and a high amount of volcanic cones imaged. The variations in the distribution of the SDR's along the margin, the presence of the HBB and Endymion Spur all suggest that the break-up process was not uniform alongstrike. The division of the margin into three sectors reveals that structural segmentation played an important role in producing the variations along the margin. Break- up initiated in the south and progressed north producing the SDR packages witnessed, when the HBB was encountered the focus of break-up moved seaward of the block. The northern sector was closer to the Iceland Hotspot and hence a greater amount of volcanism is encountered. The smooth oceanic basement also indicates a high thermal flux

[The economic margins of activities of a bovine practitioner on dairy farms].

PubMed

van Genugten, A J M; van Haaften, J A; Hogeveen, H

2011-11-01

Because of lower margins and market liberalisation veterinarians and farmers are increasingly negotiating rates. Therefore, the margins of veterinarians are under pressure. In addition, the sales if drugs, performance of operations or giving of advice are more and more separated. These developments give veterinarians uncertainty about the profitability of their activities for dairy farmers. Not much is known about margins on veterinary activities on dairy farms. Moreover, it is interesting to see how much margins of the bovine practitioner differ between veterinary practises and dairy farms. In this study, invoices for bovine activities of 14 veterinary practises were combined with milk production registration data of the dairy farms of these practices. This way, the gross margin per bovine practitioner could be studied for the different veterinary practise. Moreover the relation between gross margin and specification of the veterinary practise could be studied. Finally, the gross margin per dairy farm and the factors that influenced this gross margin were studied. The most important result was the observation that the gross margin per bovine practitioner was dependent on the number of dairy farms per practitioner, the margin on drugs and the region of the veterinary practise. The size of the veterinary practise, the share of the dairy farming within the practise and the source of the gross margin (drugs, time or operations) did not influence the gross margin. Variables that explained the gross margin per dairy farm were, amongst others, the number of dairy cows, the milk production level of the farms and participation in PIR-DAP (a system to support the veterinarians herd health and management program). There is no relation of gross margin per dairy farm and the veterinary practise or region.

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)

Athletics and Academic Achievement in Latino Youth: A Cautionary Tale

ERIC Educational Resources Information Center

Chen, Wei; Harklau, Linda

2017-01-01

Participation in extracurricular activities has been associated with enhanced academic achievement in Latino youth. Based on a longitudinal case study of one immigrant adolescent, this article finds that athletic participation is in itself neither a wholly positive or negative influence on Latino school achievement. Rather, effects of…

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…

Why are hyperactivity and academic achievement related?

PubMed

Saudino, Kimberly J; Plomin, Robert

2007-01-01

Although a negative association between hyperactivity and academic achievement is well documented, little is known about the genetic and/or environmental mechanisms responsible for the association. The present study explored links between parent and teacher ratings of hyperactive behavior problems and teacher-assessed achievement in a sample of 1,876 twin pairs (mean age 7.04 years). The results did not differ across rater, nor were there significant differences between males or females or for twins in the same or different classrooms. Hyperactivity was significantly correlated with achievement. Multivariate model-fitting analyses revealed significant genetic and nonshared environmental covariance between the two phenotypes. In addition, bivariate heritabilities were substantial, indicating that the phenotypic correlations between hyperactivity and achievement were largely mediated by genetic influences.

Double negative acoustic metastructure for attenuation of acoustic emissions

NASA Astrophysics Data System (ADS)

Kumar, Sanjay; Bhushan, Pulak; Prakash, Om; Bhattacharya, Shantanu

2018-03-01

Acoustic metamaterials hold great potential for attenuation of low frequency acoustic emissions. However, a fundamental challenge is achieving high transmission loss over a broad frequency range. In this work, we report a double negative acoustic metastructure for absorption of low frequency acoustic emissions in an aircraft. This is achieved by utilizing a periodic array of hexagonal cells interconnected with a neck and mounted with an elastic membrane on both ends. An average transmission loss of 56 dB under 500 Hz and an overall absorption of over 48% have been realized experimentally. The negative mass density is derived from the dipolar resonances created as a result of the in-phase movement of the membranes. Further, the negative bulk modulus is ascribed to the combined effect of out-of-phase acceleration of the membranes and the Helmholtz resonator. The proposed metastructure enables absorption of low frequency acoustic emissions with improved functionality that is highly desirable for varied applications.

Rapid transfer alignment of an inertial navigation system using a marginal stochastic integration filter

NASA Astrophysics Data System (ADS)

Zhou, Dapeng; Guo, Lei

2018-01-01

This study aims to address the rapid transfer alignment (RTA) issue of an inertial navigation system with large misalignment angles. The strong nonlinearity and high dimensionality of the system model pose a significant challenge to the estimation of the misalignment angles. In this paper, a 15-dimensional nonlinear model for RTA has been exploited, and it is shown that the functions for the model description exhibit a conditionally linear substructure. Then, a modified stochastic integration filter (SIF) called marginal SIF (MSIF) is developed to incorporate into the nonlinear model, where the number of sample points is significantly reduced but the estimation accuracy of SIF is retained. Comparisons between the MSIF-based RTA and the previously well-known methodologies are carried out through numerical simulations and a van test. The results demonstrate that the newly proposed method has an obvious accuracy advantage over the extended Kalman filter, the unscented Kalman filter and the marginal unscented Kalman filter. Further, the MSIF achieves a comparable performance to SIF, but with a significantly lower computation load.

Quantifying Safety Margin Using the Risk-Informed Safety Margin Characterization (RISMC)

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

Grabaskas, David; Bucknor, Matthew; Brunett, Acacia

2015-04-26

The Risk-Informed Safety Margin Characterization (RISMC), developed by Idaho National Laboratory as part of the Light-Water Reactor Sustainability Project, utilizes a probabilistic safety margin comparison between a load and capacity distribution, rather than a deterministic comparison between two values, as is usually done in best-estimate plus uncertainty analyses. The goal is to determine the failure probability, or in other words, the probability of the system load equaling or exceeding the system capacity. While this method has been used in pilot studies, there has been little work conducted investigating the statistical significance of the resulting failure probability. In particular, it ismore » difficult to determine how many simulations are necessary to properly characterize the failure probability. This work uses classical (frequentist) statistics and confidence intervals to examine the impact in statistical accuracy when the number of simulations is varied. Two methods are proposed to establish confidence intervals related to the failure probability established using a RISMC analysis. The confidence interval provides information about the statistical accuracy of the method utilized to explore the uncertainty space, and offers a quantitative method to gauge the increase in statistical accuracy due to performing additional simulations.« less

Lack of independent significance of a close (<1 mm) circumferential resection margin involvement in esophageal and junctional cancer.

PubMed

O'Farrell, N J; Donohoe, C L; Muldoon, C; Costelloe, J M; King, S; Ravi, N; Reynolds, J V

2013-08-01

For rectal cancer, an involved circumferential resection margin (CRM), defined as tumor cells within 1 mm of the CRM, is of established prognostic significance. This definition for the esophagus, however, is controversial, with the UK Royal College of Pathologists (RCP) recommending the 1 mm definition, while the College of American Pathologists (CAP) advises that only tumor cells at the cut margin (0 mm) define an incomplete (R1) resection. The aim of this study was to compare the clinical significance of both definitions in patients with pT3 tumors. CAP- and RCP-defined CRM status in patients treated by surgery only or by multimodal therapy was recorded prospectively in a comprehensive database from May 2003 to May 2011. Kaplan-Meier survival curves were generated, and factors affecting survival were assessed by univariate and multivariate analysis. A total of 157 of 340 patients had pT3 esophageal tumors, with RCP-positive CRM in 60 %, and 18 % by CAP. There were no significant differences between RCP-positive CRM and negative margins for node-positive disease, local recurrence, and survival. CAP-positive CRM was associated with positive nodes (P = 0.036) and poorer survival (P = 0.023). Multivariate analysis revealed nodal invasion to be the only independent prognostic variable (P = 0.004). A CRM margin of <1 mm is common in pT3 esophageal tumors, a finding consistent with other reports. The <1 mm definition was not associated with node positivity, local recurrence, or survival, in contrast to actual involvement at the margin, suggesting lack of independent prognostic significance of the RCP definition and possible superiority of the CAP criteria for prospective registration of CRM.

Robot-assisted radical prostatectomy: Multiparametric MR imaging-directed intraoperative frozen-section analysis to reduce the rate of positive surgical margins.

PubMed

Petralia, Giuseppe; Musi, Gennaro; Padhani, Anwar R; Summers, Paul; Renne, Giuseppe; Alessi, Sarah; Raimondi, Sara; Matei, Deliu V; Renne, Salvatore L; Jereczek-Fossa, Barbara A; De Cobelli, Ottavio; Bellomi, Massimo

2015-02-01

To investigate whether use of multiparametric magnetic resonance (MR) imaging-directed intraoperative frozen-section (IFS) analysis during nerve-sparing robot-assisted radical prostatectomy reduces the rate of positive surgical margins. This retrospective analysis of prospectively acquired data was approved by an institutional ethics committee, and the requirement for informed consent was waived. Data were reviewed for 134 patients who underwent preoperative multiparametric MR imaging (T2 weighted, diffusion weighted, and dynamic contrast-material enhanced) and nerve-sparing robot-assisted radical prostatectomy, during which IFS analysis was used, and secondary resections were performed when IFS results were positive for cancer. Control patients (n = 134) matched for age, prostate-specific antigen level, and stage were selected from a pool of 322 patients who underwent nerve-sparing robot-assisted radical prostatectomy without multiparametric MR imaging and IFS analysis. Rates of positive surgical margins were compared by means of the McNemar test, and a multivariate conditional logistic regression model was used to estimate the odds ratio of positive surgical margins for patients who underwent MR imaging and IFS analysis compared with control subjects. Eighteen patients who underwent MR imaging and IFS analysis underwent secondary resections, and 13 of these patients were found to have negative surgical margins at final pathologic examination. Positive surgical margins were found less frequently in the patients who underwent MR imaging and IFS analysis than in control patients (7.5% vs 18.7%, P = .01). When the differences in risk factors are taken into account, patients who underwent MR imaging and IFS had one-seventh the risk of having positive surgical margins relative to control patients (adjusted odds ratio: 0.15; 95% confidence interval: 0.04, 0.61). The significantly lower rate of positive surgical margins compared with that in control patients provides

Intrafraction Prostate Translations and Rotations During Hypofractionated Robotic Radiation Surgery: Dosimetric Impact of Correction Strategies and Margins

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

Water, Steven van de, E-mail: s.vandewater@erasmusmc.nl; Valli, Lorella; Alma Mater Studiorum, Department of Physics and Astronomy, Bologna University, Bologna

Purpose: To investigate the dosimetric impact of intrafraction prostate motion and the effect of robot correction strategies for hypofractionated CyberKnife treatments with a simultaneously integrated boost. Methods and Materials: A total of 548 real-time prostate motion tracks from 17 patients were available for dosimetric simulations of CyberKnife treatments, in which various correction strategies were included. Fixed time intervals between imaging/correction (15, 60, 180, and 360 seconds) were simulated, as well as adaptive timing (ie, the time interval reduced from 60 to 15 seconds in case prostate motion exceeded 3 mm or 2° in consecutive images). The simulated extent of robot corrections was alsomore » varied: no corrections, translational corrections only, and translational corrections combined with rotational corrections up to 5°, 10°, and perfect rotational correction. The correction strategies were evaluated for treatment plans with a 0-mm or 3-mm margin around the clinical target volume (CTV). We recorded CTV coverage (V{sub 100%}) and dose-volume parameters of the peripheral zone (boost), rectum, bladder, and urethra. Results: Planned dose parameters were increasingly preserved with larger extents of robot corrections. A time interval between corrections of 60 to 180 seconds provided optimal preservation of CTV coverage. To achieve 98% CTV coverage in 98% of the treatments, translational and rotational corrections up to 10° were required for the 0-mm margin plans, whereas translational and rotational corrections up to 5° were required for the 3-mm margin plans. Rectum and bladder were spared considerably better in the 0-mm margin plans. Adaptive timing did not improve delivered dose. Conclusions: Intrafraction prostate motion substantially affected the delivered dose but was compensated for effectively by robot corrections using a time interval of 60 to 180 seconds. A 0-mm margin required larger extents of additional rotational corrections

Geomorphic characterization of the U.S. Atlantic continental margin

USGS Publications Warehouse

Brothers, Daniel S.; ten Brink, Uri S.; Andrews, Brian D.; Chaytor, Jason D.

2013-01-01

The increasing volume of multibeam bathymetry data collected along continental margins is providing new opportunities to study the feedbacks between sedimentary and oceanographic processes and seafloor morphology. Attempts to develop simple guidelines that describe the relationships between form and process often overlook the importance of inherited physiography in slope depositional systems. Here, we use multibeam bathymetry data and seismic reflection profiles spanning the U.S. Atlantic outer continental shelf, slope and rise from Cape Hatteras to New England to quantify the broad-scale, across-margin morphological variation. Morphometric analyses suggest the margin can be divided into four basic categories that roughly align with Quaternary sedimentary provinces. Within each category, Quaternary sedimentary processes exerted heavy modification of submarine canyons, landslide complexes and the broad-scale morphology of the continental rise, but they appear to have preserved much of the pre-Quaternary, across-margin shape of the continental slope. Without detailed constraints on the substrate structure, first-order morphological categorization the U.S. Atlantic margin does not provide a reliable framework for predicting relationships between form and process.

Intraoperative monitoring of marginal mandibular nerve during neck dissection.

PubMed

Tirelli, Giancarlo; Bergamini, Pier Riccardo; Scardoni, Alessandro; Gatto, Annalisa; Boscolo Nata, Francesca; Marcuzzo, Alberto Vito

2018-05-01

The purpose of this study was to assess the efficacy of intraoperative nerve integrity monitoring (NIM) to prevent marginal mandibular nerve injuries during neck dissection. This prospective study compared 36 patients undergoing NIM-assisted neck dissection from July 2014 to March 2015 to a cohort of 35 patients subjected to neck dissection over an identical period of time before the technique was introduced. We also assessed possible correlations between marginal mandibular nerve injuries and other factors, such as anthropometric measurements, presence of clinical neck metastases, type of neck dissection, and site of primary tumor. The incidence of marginal mandibular nerve paralyses was significantly lower among the group of patients undergoing NIM-assisted neck dissection (P = .021). There was no significant difference in the duration of the procedure, and the technique resulted in a limited increase of cost. No other factor seemed to influence the onset of marginal mandibular nerve palsy. In our opinion, NIM is a valuable aid for preventing marginal mandibular nerve injuries during neck dissection. © 2018 Wiley Periodicals, Inc.

How Distorted Thinking Influence Arab Children Academic Achievement in Israel?

ERIC Educational Resources Information Center

Gith, Emad

2018-01-01

The purpose of the current study was to examine the relation between the parents Cognitive Distortion and Arab children academic achievements in Israel. 52 fifth grade Arab Children and their parents from Israel were participated. The results indicated that parent's cognitive distortion related negatively to children academic achievements; there…

Analysis of Relationships among Burnout, Academic Achievement, and Self-Regulation

ERIC Educational Resources Information Center

Duru, Erdinç; Duru, Sibel; Balkis, Murat

2014-01-01

This study examined the relationships among burnout, academic achievement, and self-regulation with two structural models. The participants were 383 undergraduates with different majors in a university in the western part of Turkey. The results showed that academic achievement was negatively associated with three dimensions of burnout and was…

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 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 a...

Polar continental margins: Studies off East Greenland

NASA Astrophysics Data System (ADS)

Mienert, J.; Thiede, J.; Kenyon, N. H.; Hollender, F.-J.

The passive continental margin off east Greenland has been shaped by tectonic and sedimentary processes, and typical physiographic patterns have evolved over the past few million years under the influence of the late Cenozoic Northern Hemisphere glaciations. The Greenland ice shield has been particularly affected.GLORIA (Geological Long Range Inclined Asdic), the Institute of Oceanographic Sciences' (IOS) long-range, side-scan sonar, was used on a 1992 RV Livonia cruise to map large-scale changes in sedimentary patterns along the east Greenland continental margin. The overall objective of this research program was to determine the variety of large-scale seafloor processes to improve our understanding of the interaction between ice sheets, current regimes, and sedimentary processes. In cooperation with IOS and the RV Livonia, a high-quality set of seafloor data has been produced. GLORIA'S first survey of east Greenland's continental margin covered several 1000- × 50-km-wide swaths (Figure 1) and yielded an impressive sidescan sonar image of the complete Greenland Basin and margin (about 250,000 km2). A mosaic of the data was made at a scale of 1:375,000. The base map was prepared with a polar stereographic projection having a standard parallel of 71°.

Sustainable biomass production on Marginal Lands (SEEMLA)

NASA Astrophysics Data System (ADS)

Barbera, Federica; Baumgarten, Wibke; Pelikan, Vincent

2017-04-01

Sustainable biomass production on Marginal Lands (SEEMLA) The main objective of the H2020 funded EU project SEEMLA (acronym for Sustainable Exploitation of Biomass for Bioenergy from Marginal Lands in Europe) is the establishment of suitable innovative land-use strategies for a sustainable production of plant-based energy on marginal lands while improving general ecosystem services. The use of marginal lands (MagL) could contribute to the mitigation of the fast growing competition between traditional food production and production of renewable bio-resources on arable lands. SEEMLA focuses on the promotion of re-conversion of MagLs for the production of bioenergy through the direct involvement of farmers and forester, the strengthening of local small-scale supply chains, and the promotion of plantations of bioenergy plants on MagLs. Life cycle assessment is performed in order to analyse possible impacts on the environment. A soil quality rating tool is applied to define and classify MagL. Suitable perennial and woody bioenergy crops are selected to be grown in pilot areas in the partner countries Ukraine, Greece and Germany. SEEMLA is expected to contribute to an increasing demand of biomass for bioenergy production in order to meet the 2020 targets and beyond.

Evidence of a Differential Effect of Ability Grouping on the Reading Achievement Growth of Language-Minority Hispanics

ERIC Educational Resources Information Center

Robinson, Joseph P.

2008-01-01

Ability grouping is sometimes thought to exacerbate inequality by increasing achievement gaps; however, ability grouping may in fact benefit a fast growing and often marginalized student population: children from non-English-speaking home environments. The level-appropriate, small-group instruction received in reading ability groups may be…

Evaluation of the marginal fit of metal copings fabricated on three different marginal designs using conventional and accelerated casting techniques: an in vitro study.

PubMed

Vaidya, Sharad; Parkash, Hari; Bhargava, Akshay; Gupta, Sharad

2014-01-01

Abundant resources and techniques have been used for complete coverage crown fabrication. Conventional investing and casting procedures for phosphate-bonded investments require a 2- to 4-h procedure before completion. Accelerated casting techniques have been used, but may not result in castings with matching marginal accuracy. The study measured the marginal gap and determined the clinical acceptability of single cast copings invested in a phosphate-bonded investment with the use of conventional and accelerated methods. One hundred and twenty cast coping samples were fabricated using conventional and accelerated methods, with three finish lines: Chamfer, shoulder and shoulder with bevel. Sixty copings were prepared with each technique. Each coping was examined with a stereomicroscope at four predetermined sites and measurements of marginal gaps were documented for each. A master chart was prepared for all the data and was analyzed using Statistical Package for the Social Sciences version. Evidence of marginal gap was then evaluated by t-test. Analysis of variance and Post-hoc analysis were used to compare two groups as well as to make comparisons between three subgroups . Measurements recorded showed no statistically significant difference between conventional and accelerated groups. Among the three marginal designs studied, shoulder with bevel showed the best marginal fit with conventional as well as accelerated casting techniques. Accelerated casting technique could be a vital alternative to the time-consuming conventional casting technique. The marginal fit between the two casting techniques showed no statistical difference.

Marginal states in a cubic autocatalytic reaction

NASA Astrophysics Data System (ADS)

Das, Debojyoti; Ghosh, Pushpita; Ray, Deb Shankar

2011-09-01

Marginal steady state belongs to a special class of states in nonlinear dynamics. To realize this state we consider a cubic autocatalytic reaction A + 2B → 3B in a continuous-stirred-tank-reactor, where the flow rate of the reactant A can be controlled to manipulate the dynamical behavior of the open system. We demonstrate that when the flow rate is weakly noisy the autocatalytic reaction admits of a steady state which is marginal in nature and is surrounded by infinite number of periodic trajectories. When the uncatalyzed reaction A → B is included in the reaction scheme, there exists a marginal steady state which is a critical state corresponding to the point of transition between the flow branch and the equilibrium branch, similar to gas-liquid critical point of transition. This state loses its stability in the weak noise limit.

H. Pylori as a predictor of marginal ulceration: A nationwide analysis.

PubMed

Schulman, Allison R; Abougergi, Marwan S; Thompson, Christopher C

2017-03-01

Helicobacter pylori has been implicated as a risk factor for development of marginal ulceration following gastric bypass, although studies have been small and yielded conflicting results. This study sought to determine the relationship between H. pylori infection and development of marginal ulceration following bariatric surgery in a nationwide analysis. This was a retrospective cohort study using the 2012 Nationwide Inpatient Sample (NIS) database. Discharges with ICD-9-CM code indicating marginal ulceration and a secondary ICD-9-CM code for bariatric surgery were included. Primary outcome was incidence of marginal ulceration. A stepwise forward selection model was used to build the multivariate logistic regression model based on known risk factors. A P value of 0.05 was considered significant. There were 253,765 patients who met inclusion criteria. Prevalence of marginal ulceration was 3.90%. Of those patients found to have marginal ulceration, 31.20% of patients were H. pylori-positive. Final multivariate regression analysis revealed that H. pylori was the strongest independent predictor of marginal ulceration. H. pylori is an independent predictor of marginal ulceration using a large national database. Preoperative testing for and eradication of H. pylori prior to bariatric surgery may be an important preventive measure to reduce the incidence of ulcer development. © 2017 The Obesity Society.

Negative refraction imaging of acoustic metamaterial lens in the supersonic range

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

Han, Jianning; Wen, Tingdun; Key Laboratory of Electronic Testing Technology, North University of China, Taiyuan 030051

2014-05-15

Acoustic metamaterials with negative refraction index is the most promising method to overcome the diffraction limit of acoustic imaging to achieve ultrahigh resolution. In this paper, we use localized resonant phononic crystal as the unit cell to construct the acoustic negative refraction lens. Based on the vibration model of the phononic crystal, negative quality parameters of the lens are obtained while excited near the system resonance frequency. Simulation results show that negative refraction of the acoustic lens can be achieved when a sound wave transmiting through the phononic crystal plate. The patterns of the imaging field agree well with thatmore » of the incident wave, while the dispersion is very weak. The unit cell size in the simulation is 0.0005 m and the wavelength of the sound source is 0.02 m, from which we show that acoustic signal can be manipulated through structures with dimensions much smaller than the wavelength of incident wave.« less

International law poses problems for negative emissions research

NASA Astrophysics Data System (ADS)

Brent, Kerryn; McGee, Jeffrey; McDonald, Jan; Rohling, Eelco J.

2018-06-01

New international governance arrangements that manage environmental risk and potential conflicts of interests are needed to facilitate negative emissions research that is essential to achieving the large-scale CO2 removal implied by the Paris Agreement targets.

SU-F-J-17: Patient Localization Using MRI-Guided Soft Tissue for Head-And-Neck Radiotherapy: Indication for Margin Reduction and Its Feasibility

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

Qi, X; Yang, Y; Jack, N

Purpose: On-board MRI provides superior soft-tissue contrast, allowing patient alignment using tumor or nearby critical structures. This study aims to study H&N MRI-guided IGRT to analyze inter-fraction patient setup variations using soft-tissue targets and design appropriate CTV-to-PTV margin and clinical implication. Methods: 282 MR images for 10 H&N IMRT patients treated on a ViewRay system were retrospectively analyzed. Patients were immobilized using a thermoplastic mask on a customized headrest fitted in a radiofrequency coil and positioned to soft-tissue targets. The inter-fraction patient displacements were recorded to compute the PTV margins using the recipe: 2.5∑+0.7σ. New IMRT plans optimized on themore » revised PTVs were generated to evaluate the delivered dose distributions. An in-house dose deformation registration tool was used to assess the resulting dosimetric consequences when margin adaption is performed based on weekly MR images. The cumulative doses were compared to the reduced margin plans for targets and critical structures. Results: The inter-fraction displacements (and standard deviations), ∑ and σ were tabulated for MRI and compared to kVCBCT. The computed CTV-to-PTV margin was 3.5mm for soft-tissue based registration. There were minimal differences between the planned and delivered doses when comparing clinical and the PTV reduced margin plans: the paired t-tests yielded p=0.38 and 0.66 between the planned and delivered doses for the adapted margin plans for the maximum cord and mean parotid dose, respectively. Target V95 received comparable doses as planned for the reduced margin plans. Conclusion: The 0.35T MRI offers acceptable soft-tissue contrast and good spatial resolution for patient alignment and target visualization. Better tumor conspicuity from MRI allows soft-tissue based alignments with potentially improved accuracy, suggesting a benefit of margin reduction for H&N radiotherapy. The reduced margin plans (i.e., 2 mm

Correlation of breast tissue histology and optical signatures to improve margin assessment techniques

NASA Astrophysics Data System (ADS)

Kennedy, Stephanie; Caldwell, Matthew; Bydlon, Torre; Mulvey, Christine; Mueller, Jenna; Wilke, Lee; Barry, William; Ramanujam, Nimmi; Geradts, Joseph

2016-06-01

Optical spectroscopy is sensitive to morphological composition and has potential applications in intraoperative margin assessment. Here, we evaluate ex vivo breast tissue and corresponding quantified hematoxylin & eosin images to correlate optical scattering signatures to tissue composition stratified by patient characteristics. Adipose sites (213) were characterized by their cell area and density. All other benign and malignant sites (181) were quantified using a grid method to determine composition. The relationships between mean reduced scattering coefficient (<μs‧>), and % adipose, % collagen, % glands, adipocyte cell area, and adipocyte density were investigated. These relationships were further stratified by age, menopausal status, body mass index (BMI), and breast density. We identified a positive correlation between <μs‧> and % collagen and a negative correlation between <μs‧> and age and BMI. Increased collagen corresponded to increased <μs‧> variability. In postmenopausal women, <μs‧> was similar regardless of fibroglandular content. Contributions from collagen and glands to <μs‧> were independent and equivalent in benign sites; glands showed a stronger positive correlation than collagen to <μs‧> in malignant sites. Our data suggest that scattering could differentiate highly scattering malignant from benign tissues in postmenopausal women. The relationship between scattering and tissue composition will support improved scattering models and technologies to enhance intraoperative optical margin assessment.

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…

Microleakage of Four Dental Cements in Metal Ceramic Restorations With Open Margins.

PubMed

Eftekhar Ashtiani, Reza; Farzaneh, Babak; Azarsina, Mohadese; Aghdashi, Farzad; Dehghani, Nima; Afshari, Aisooda; Mahshid, Minu

2015-11-01

Fixed prosthodontics is a routine dental treatment and microleakage is a major cause of its failure. The aim of this study was to assess the marginal microleakage of four cements in metal ceramic restorations with adapted and open margins. Sixty sound human premolars were selected for this experimental study performed in Tehran, Iran and prepared for full-crown restorations. Wax patterns were formed leaving a 300 µm gap on one of the proximal margins. The crowns were cast and the samples were randomly divided into four groups based on the cement used. Copings were cemented using zinc phosphate cement (Fleck), Fuji Plus resin-modified glass ionomer, Panavia F2.0 resin cement, or G-Cem resin cement, according to the manufacturers' instructions. Samples were immersed in 2% methylene blue solution. After 24 hours, dye penetration was assessed under a stereomicroscope and analyzed using the respective software. Data were analyzed using ANOVA, paired t-tests, and Kruskal-Wallis, Wilcoxon, and Mann-Whitney tests. The least microleakage occurred in the Panavia F2.0 group (closed margin, 0.18 mm; open margin, 0.64 mm) and the maximum was observed in the Fleck group (closed margin, 1.92 mm; open margin, 3.32 mm). The Fleck group displayed significantly more microleakage compared to the Fuji Plus and Panavia F2.0 groups (P < 0.001) in both closed and open margins. In open margins, differences in microleakage between the Fuji Plus and G-Cem as well as between the G-Cem and Panavia F2.0 groups were significant (P < 0.001). In closed margins, only the G-Cem group displayed significantly more microleakage as compared to the Panavia F2.0 group (P < 0.05). Paired t-test results showed significantly more microleakage in open margins compared to closed margins, except in the Fuji Plus group (P = 0.539). Fuji Plus cement exhibited better sealing ability in closed and open margins compared to G-Cem and Fleck cements. When using G-Cem and Fleck cements for full metal ceramic

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…

Clustered marginalization of minorities during social transitions induced by co-evolution of behaviour and network structure

NASA Astrophysics Data System (ADS)

Schleussner, Carl-Friedrich; Donges, Jonathan F.; Engemann, Denis A.; Levermann, Anders

2016-08-01

Large-scale transitions in societies are associated with both individual behavioural change and restructuring of the social network. These two factors have often been considered independently, yet recent advances in social network research challenge this view. Here we show that common features of societal marginalization and clustering emerge naturally during transitions in a co-evolutionary adaptive network model. This is achieved by explicitly considering the interplay between individual interaction and a dynamic network structure in behavioural selection. We exemplify this mechanism by simulating how smoking behaviour and the network structure get reconfigured by changing social norms. Our results are consistent with empirical findings: The prevalence of smoking was reduced, remaining smokers were preferentially connected among each other and formed increasingly marginalized clusters. We propose that self-amplifying feedbacks between individual behaviour and dynamic restructuring of the network are main drivers of the transition. This generative mechanism for co-evolution of individual behaviour and social network structure may apply to a wide range of examples beyond smoking.

Clustered marginalization of minorities during social transitions induced by co-evolution of behaviour and network structure.

PubMed

Schleussner, Carl-Friedrich; Donges, Jonathan F; Engemann, Denis A; Levermann, Anders

2016-08-11

Large-scale transitions in societies are associated with both individual behavioural change and restructuring of the social network. These two factors have often been considered independently, yet recent advances in social network research challenge this view. Here we show that common features of societal marginalization and clustering emerge naturally during transitions in a co-evolutionary adaptive network model. This is achieved by explicitly considering the interplay between individual interaction and a dynamic network structure in behavioural selection. We exemplify this mechanism by simulating how smoking behaviour and the network structure get reconfigured by changing social norms. Our results are consistent with empirical findings: The prevalence of smoking was reduced, remaining smokers were preferentially connected among each other and formed increasingly marginalized clusters. We propose that self-amplifying feedbacks between individual behaviour and dynamic restructuring of the network are main drivers of the transition. This generative mechanism for co-evolution of individual behaviour and social network structure may apply to a wide range of examples beyond smoking.

PAX5 methylation detection by droplet digital PCR for ultra-sensitive deep surgical margins analysis of head and neck squamous cell carcinoma

PubMed Central

Hayashi, Masamichi; Guerrero-Preston, Rafael; Sidransky, David; Koch, Wayne M.

2015-01-01

Molecular deep surgical margin analysis has been shown to predict locoregional recurrences of head and neck squamous cell carcinoma (HNSCC). In order to improve the accuracy and versatility of the analysis, we used a highly tumor-specific methylation marker and highly sensitive detection technology to test DNA from surgical margins. Histologically cancer-negative deep surgical margin samples were prospectively collected from 82 eligible HNSCC surgeries by an imprinting procedure (n=75) and primary tissue collection (n=70). Bisulfite treated DNA from each sample was analyzed by both conventional quantitative methylation-specific polymerase chain reaction (QMSP) and QMSP by droplet digital PCR (ddQMSP) targeting PAX5 gene promoter methylation. The association between the presence of PAX5 methylation and locoregional recurrence free survival (LRFS) was evaluated. PAX5 methylation was found in 68.0% (51/75) of tumors in the imprint samples and 71.4% (50/70) in the primary tissue samples. Among cases which did not have postoperative radiation, (n=31 in imprint samples, n=29 in tissue samples), both conventional QMSP and ddQMSP revealed that PAX5 methylation positive margins was significantly associated with poor LRFS by univariate analysis. In particular, ddQMSP increased detection of the PAX5 marker from 29% to 71% in the non-radiated imprint cases. Also, PAX5 methylated imprint margins were an excellent predictor of poor LRFS (HR=3.89, 95%CI:1.19-17.52, P=0.023) by multivariate analysis. PAX5 methylation appears to be an excellent tumor-specific marker for molecular deep surgical margin analysis of HNSCC. Moreover, the ddQMSP assay displays increased sensitivity for methylation marker detection. PMID:26304463

Reappraisal with meta-analysis of bacteremia, endotoxemia, and mortality in gram-negative sepsis.

PubMed Central

Hurley, J C

1995-01-01

Among patients with suspected sepsis, endotoxemia is variably present in association with gram-negative bacteremia. A total of 738 patients with suspected sepsis from 11 studies could be classified into four groups: 131 (18%) patients had both endotoxemia and gram-negative bacteremia (group 1), 87 (12%) had only gram-negative bacteremia (group 2), and 143 (19%) had only endotoxemia (group 3); in 377 (51%) patients neither could be detected (group 4). By the statistical techniques of meta-analysis, the fatality risk for patients with either endotoxemia or gram-negative bacteremia or both was estimated with group-specific case fatality rates from these studies and expressed as an odds ratio (OR; 95% confidence interval [95% CI]) versus patients with these factors absent. This risk was increased marginally when endotoxemia was detected without gram-negative bacteremia (OR, 2.3; 95% CI, 1.3 to 4.0) or the converse (OR, 2.0; 95% CI, 1.0 to 3.8), in contrast to the striking increase when both endotoxemia and gram-negative bacteremia were detected (OR, 6.3; 95% CI, 4.0 to 10.0). Alone, neither endotoxemia nor gram-negative bacteremia is a strong predictor of outcome in patients with suspected sepsis. However, in combination, the two identify a subpopulation with a substantially increased risk of mortality. PMID:7615741

30 CFR 204.4 - What is a marginal property under this part?

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What is a marginal property under this part... REVENUE MANAGEMENT ALTERNATIVES FOR MARGINAL PROPERTIES General Provisions § 204.4 What is a marginal property under this part? (a) To qualify as a marginal property eligible for royalty prepayment or...

Microwave gain medium with negative refractive index.

PubMed

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

2014-12-19

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.

Systematic reviews: I. The correlation between laboratory tests on marginal quality and bond strength. II. The correlation between marginal quality and clinical outcome.

PubMed

Heintze, Siegward D

2007-01-01

An accepted principle in restorative dentistry states that restorations should be placed with the best marginal quality possible to avoid postoperative sensitivity, marginal discoloration, and secondary caries. Different laboratory methods claim to predict the clinical performance of restorative materials, for example, tests of bond strength and microleakage and gap analysis. The purpose of this review was twofold: (1) find studies that correlated the results of bond strength tests with either microleakage or gap analysis for the same materials, and (2) find studies that correlated the results of microleakage and/or gaps with the clinical parameters for the same materials. Furthermore, influencing factors on the results of the laboratory tests were reviewed and assessed. For the first question, searches for studies were conducted in the MEDLINE database and IADR/AADR abtracts online with specific search and inclusion criteria. The outcome for each study was assessed on the basis of the statistical test applied in the study, and finally the number of studies with or without correlation was compiled. For the second question, results of the quantitative marginal analysis of Class V restorations published by the University of Zürich with the same test protocol and prospective clinical trials were searched that investigated the same materials for at least 2 years in Class V cavities. Pearson correlation coefficients were calculated for pooled data of materials and clinical outcome parameters such as retention loss, marginal discoloration, marginal integrity, and secondary caries. For the correlation of dye penetration and clinical outcome, studies on Class V restorations published by the same research institute were searched in MEDLINE that examined the same adhesive systems as the selected clinical trials. For the correlation bond strength/microleakage, 30 studies were included into the review, and for the correlation bond strength/gap analysis 18 studies. For both

Influence of Cavity Margin Design and Restorative Material on Marginal Quality and Seal of Extended Class II Resin Composite Restorations In Vitro.

PubMed

Soliman, Sebastian; Preidl, Reinhard; Karl, Sabine; Hofmann, Norbert; Krastl, Gabriel; Klaiber, Bernd

2016-01-01

To investigate the influence of three cavity designs on the marginal seal of large Class II cavities restored with low-shrinkage resin composite limited to the enamel. One hundred twenty (120) intact human molars were randomly divided into 12 groups, with three different cavity designs: 1. undermined enamel, 2. box-shaped, and 3. proximal bevel. The teeth were restored with 1. an extra-low shrinkage (ELS) composite free of diluent monomers, 2. microhybrid composite (Herculite XRV), 3. nanohybrid composite (Filtek Supreme XTE), and 4. silorane-based composite (Filtek Silorane). After artificial aging by thermocycling and storage in physiological saline, epoxy resin replicas were prepared. To determine the integrity of the restorations' approximal margins, two methods were sequentially employed: 1. replicas were made of the 120 specimens and examined using SEM, and 2. the same 120 specimens were immersed in AgNO3 solution, and the dye penetration depth was observed with a light microscope. Statistical analysis was performed using the Kruskal-Wallis and the Dunn-Bonferroni tests. After bevel preparation, SEM observations showed that restorations did not exhibit a higher percentage of continuous margin (SEM-analysis; p>0.05), but more leakage was found than with the other cavity designs (p<0.05). The lowest percentage of continuous margin was observed in ELS restorations (p<0.05). More fractured margins were observed in the undermined enamel cavity design groups (p<0.05). Bevel preparation failed to improve margin quality in large Class II composite restorations and is no longer recommended. However, undermined enamel should be removed to prevent enamel fractures.

Holistic Approach Offers Potential to Quantify Mass Fluxes Across Continental Margins

NASA Astrophysics Data System (ADS)

Kuehl, Steven; Carter, Lionel; Gomez, Basil; Trustrum, Noel

Most humans live on and utilize the continental margin, the surface of which changes continually in response to environmental perturbations such as weather, climate change, tectonism, earthquakes, volcanism, sea level, and human settlement and land use. Part of the margin is above sea level and the rest is submarine, but these land and seascape components are contiguous, and material transport from source to sink occurs as a seamless cascade. The margin responds to environmental perturbations by changing the nature and magnitude of a variety of important functions, including the distribution of soil formation and erosion; biogeochemical functioning (especially the storage and release of water, limiting nutrients and contaminants); and the form and behavior of geomorphic components from hill slopes and floodplains through the coastal zone to the continental rise. While some areas of the margin are eroding-for example, hill slopes-others accumulate sediment, such as tectonic basins and continental slope and rise. These areas record the history of surface changes. A major goal of the Earth science community is to provide quantitative explanations and predictions of the effects of environmental perturbations on surface changes and preserved sedimentary strata of continental margins. In past decades, margins have been investigated piecemeal by researchers who have tended to focus on a particular segment from one disciplinary perspective while eschewing the broader perspective of the margin as an interconnected whole. Recognizing this shortcoming, the U.S. National Science Foundation (NSF) has initiated the MARGINS Source-to-Sink (S2S) program, which, for the first time, will attempt to understand the functioning of entire margin systems through dedicated observational and community modeling studies. Following input from the Earth science community, the Waipaoa Sedimentary System (WSS) of the North Island, New Zealand, was chosen as one of the focus sites for possible

The Cadiz margin study off Spain: An introduction

USGS Publications Warehouse

Nelson, C.H.; Maldonado, A.

1999-01-01

The Cadiz continental margin of the northeastern Gulf of Cadiz off Spain was selected for a multidisciplinary project because of the interplay of complex tectonic history between the Iberian and African plates, sediment supply from multiple sources, and unique Mediterranean Gateway inflow and outflow currents. The nature of this complex margin, particularly during the last 5 million years, was investigated with emphasis on tectonic history, stratigraphic sequences, marine circulation, contourite depositional facies, geotechnical properties, geologic hazards, and human influences such as dispersal of river contaminants. This study provides an integrated view of the tectonic, sediment supply and oceanographic factors that control depositional processes and growth patterns of the Cadiz and similar modem and ancient continental margins.

Undifferentiated negative affect and impulsivity in borderline personality and depressive disorders: A momentary perspective.

PubMed

Tomko, Rachel L; Lane, Sean P; Pronove, Lisa M; Treloar, Hayley R; Brown, Whitney C; Solhan, Marika B; Wood, Phillip K; Trull, Timothy J

2015-08-01

Individuals with borderline personality disorder (BPD) often report experiencing several negative emotions simultaneously, an indicator of "undifferentiated" negative affect. The current study examined the relationship between undifferentiated negative affect and impulsivity. Participants with a current BPD (n = 67) or depressive disorder (DD; n = 38) diagnosis carried an electronic diary for 28 days, reporting on emotions and impulsivity when randomly prompted (up to 6 times per day). Undifferentiated negative affect was quantified using momentary intraclass correlation coefficients, which indicated how consistently negative emotion items were rated across fear, hostility, and sadness subscales. Undifferentiated negative affect at the occasion-level, day-level, and across 28 days was used to predict occasion-level impulsivity. Multilevel modeling was used to test the hypothesis that undifferentiated negative emotion would be a significant predictor of momentary impulsivity above and beyond levels of overall negative affect. Undifferentiated negative affect at the occasion and day levels were significant predictors of occasion-level impulsivity, but undifferentiated negative affect across the 28-day study period was only marginally significant. Results did not differ depending on BPD or DD status, though individuals with BPD did report significantly greater momentary impulsivity and undifferentiated negative affect. Undifferentiated negative affect may increase risk for impulsivity among individuals with BPD and depressive disorders, and the current data suggest that this process can be relatively immediate as well as cumulative over the course of a day. This research supports the consideration of undifferentiated negative affect as a transdiagnostic construct, but one that may be particularly relevant for those with BPD. (c) 2015 APA, all rights reserved).

Undifferentiated Negative Affect and Impulsivity in Borderline Personality and Depressive Disorders: A Momentary Perspective

PubMed Central

Pronove, Lisa M.; Treloar, Hayley R.; Brown, Whitney C.; Solhan, Marika B.; Wood, Phillip K.; Trull, Timothy J.

2015-01-01

Individuals with borderline personality disorder (BPD) often report experiencing several negative emotions simultaneously, an indicator of “undifferentiated” negative affect. The current study examined the relationship between undifferentiated negative affect and impulsivity. Participants with a current BPD (n = 67) or depressive disorder (DD; n = 38) diagnosis carried an electronic diary for 28 days, reporting on emotions and impulsivity when randomly prompted (up to 6 times per day). Undifferentiated negative affect was quantified using momentary intraclass correlation coefficients, which indicated how consistently negative emotion items were rated across fear, hostility, and sadness subscales. Undifferentiated negative affect at the occasion-level, day-level, and across 28 days was used to predict occasion-level impulsivity. Multilevel modeling was used to test the hypothesis that undifferentiated negative emotion would be a significant predictor of momentary impulsivity above and beyond levels of overall negative affect. Undifferentiated negative affect at the occasion and day levels were significant predictors of occasion-level impulsivity, but undifferentiated negative affect across the 28-day study period was only marginally significant. Results did not differ depending on BPD or DD status, though BPD individuals did report significantly greater momentary impulsivity and undifferentiated negative affect. Undifferentiated negative affect may increase risk for impulsivity among individuals with BPD and depressive disorders, and the current data suggest that this process can be relatively immediate as well as cumulative over the course of a day. This research supports the consideration of undifferentiated negative affect as a transdiagnostic construct, but one that may be particularly relevant for those with BPD. PMID:26147324

MRI Evaluation of Resection Margins in Bone Tumour Surgery

PubMed Central

Traore, Sidi Yaya; Lecouvet, Frédéric; Galant, Christine

2014-01-01

In 12 patients operated on for bone sarcoma resection, a postoperative magnetic resonance imaging of the resection specimens was obtained in order to assess the surgical margins. Margins were classified according to MRI in R0, R1, and R2 by three independent observers: a radiologist and two orthopaedic surgeons. Final margin evaluation (R0, R1, and R2) was assessed by a confirmed pathologist. Agreement for margin evaluation between the pathologist and the radiologist was perfect (κ = 1). Agreement between the pathologist and an experienced orthopaedic surgeon was very good while it was fair between the pathologist and a junior orthopaedic surgeon. MRI should be considered as a tool to give quick information about the adequacy of margins and to help the pathologist to focus on doubtful areas and to spare time in specimen analysis. But it may not replace the pathological evaluation that gives additional information about tumor necrosis. This study shows that MRI extemporaneous analysis of a resection specimen may be efficient in bone tumor oncologic surgery, if made by an experienced radiologist with perfect agreement with the pathologist. PMID:24976785

Self-Esteem, Achievement Goals, and Self-Handicapping in College Physical Education.

PubMed

Chen, Zuosong; Sun, Kaihong; Wang, Kun

2017-01-01

This study aims to investigate the relationships among self-esteem, achievement goals, and self-handicapping and the potential mediating role of achievement goals in the relationship between self-esteem and self-handicapping in college physical education. The participants were 320 Chinese college students. Three validated scales were employed to assess participants' self-esteem, achievement goals, and self-handicapping in college physical education. Results showed that self-esteem had a negative effect on self-handicapping. Self-esteem had a positive effect on mastery goals, but had a negative effect on performance-avoidance goals. Mastery goals had a negative effect and performance-avoidance goals had a positive effect on self-handicapping. Moreover, mastery goals and performance-avoidance goals partially mediated the relationship between self-esteem and self-handicapping, and self-esteem had both direct and indirect effects on self-handicapping in college physical education. The findings indicate that improving individual's self-esteem and promoting mastery goals while reducing performance-avoidance goals may be relevant strategies to reduce self-handicapping in college physical education.

Positive Feelings towards the Learning of Mathematics for Low Achievers

ERIC Educational Resources Information Center

Tong, Cherng Luen; Leong, Yew Hoong; Quek, Khiok Seng

2013-01-01

A common area of difficulty and frustration for low achieving students is the operations involving negative numbers. The main objective of our innovations in this area with two classes of Year 7 low achieving students was to develop positive feelings towards mathematics, in particular of an appreciation for the "reasonableness" and clear…

Marginal revenue and length of stay in inpatient psychiatry.

PubMed

Pletscher, Mark

2016-09-01

This study examines the changes in marginal revenue during psychiatric inpatient stays in a large Swiss psychiatric hospital after the introduction of a mixed reimbursement system with tariff rates that vary over length of stay. A discrete time duration model with a difference-in-difference specification and time-varying coefficients is estimated to assess variations in policy effects over length of stay. Among patients whose costs are fully reimbursed by the mixed scheme, the model demonstrates a significant effect of marginal revenue on length of stay. No significant policy effects are found among patients for whom only health insurance rates are delivered as mixed tariffs and government contributions are made retrospectively. The results indicate that marginal revenue can affect length of stay in inpatient psychiatry facilities, but that the reduction in marginal revenue must be sufficiently large.

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…

Along-strike supply of volcanic rifted margins: Implications for plume-influenced rifting and sudden along-strike transitions between volcanic and non-volcanic rifted margins

NASA Astrophysics Data System (ADS)

Ranero, C. R.; Phipps Morgan, J.

2006-12-01

The existence of sudden along-strike transitions between volcanic and non-volcanic rifted margins is an important constraint for conceptual models of rifting and continental breakup. We think there is a promising indirect approach to infer the maximum width of the region of upwelling that exists beneath a rifted margin during the transition from rifting to seafloor-spreading. We infer this width of ~30km from the minimum length of the ridge-offsets that mark the limits of the `region of influence' of on-ridge plumes on the axial relief, axial morphology, and crustal thickness along the ridge and at the terminations of fossil volcanic rifted margins. We adopt Vogt's [1972] hypothesis for along-ridge asthenospheric flow in a narrow vertical slot beneath the axis of plume-influenced `macro-segments' and volcanic rifted margins. We find that: (1) There is a threshold distance to the lateral offsets that bound plume-influenced macrosegments; all such `barrier offsets' are greater than ~30km, while smaller offsets do not appear to be a barrier to along-axis flow. This pattern is seen in the often abrupt transitions between volcanic and non-volcanic rifted margins; these transitions coincide with >30km ridge offsets that mark the boundary between the smooth seafloor morphology and thick crust of a plume- influenced volcanic margin and a neighboring non-volcanic margin, as recorded in 180Ma rifting of the early N. Atlantic, the 42Ma rifting of the Kerguelen-Broken Ridge, and the 66Ma Seychelles-Indian rifting in the Indian Ocean. (2) A similar pattern is seen in the often abrupt transitions between `normal' and plume-influenced mid- ocean ridge segments, which is discussed in a companion presentation by Phipps Morgan and Ranero (this meeting). (3) The coexistance of adjacent volcanic and non-volcanic rifted margin segments is readily explained in this conceptual framework. If the volcanic margin macrosegment is plume-fed by hot asthenosphere along an axial ridge slot

Application of matrix singular value properties for evaluating gain and phase margins of multiloop systems. [stability margins for wing flutter suppression and drone lateral attitude control

NASA Technical Reports Server (NTRS)

Mukhopadhyay, V.; Newsom, J. R.

1982-01-01

A stability margin evaluation method in terms of simultaneous gain and phase changes in all loops of a multiloop system is presented. A universal gain-phase margin evaluation diagram is constructed by generalizing an existing method using matrix singular value properties. Using this diagram and computing the minimum singular value of the system return difference matrix over the operating frequency range, regions of guaranteed stability margins can be obtained. Singular values are computed for a wing flutter suppression and a drone lateral attitude control problem. The numerical results indicate that this method predicts quite conservative stability margins. In the second example if the eigenvalue magnitude is used instead of the singular value, as a measure of nearness to singularity, more realistic stability margins are obtained. However, this relaxed measure generally cannot guarantee global stability.

Impression management and achievement motivation: Investigating substantive links.

PubMed

Elliot, Andrew J; Aldhobaiban, Nawal; Murayama, Kou; Kobeisy, Ahmed; Gocłowska, Małgorzata A; Khyat, Aber

2018-02-01

In this research, we investigate impression management (IM) as a substantive personality variable by linking it to differentiated achievement motivation constructs, namely achievement motives (workmastery, competitiveness, fear of failure) and achievement goals (mastery-approach, mastery-avoidance, performance-approach, performance-avoidance). Study 1 revealed that IM was a positive predictor of workmastery and a negative predictor of competitiveness (with and without self-deceptive enhancement (SDE) controlled). Studies 2a and 2b revealed that IM was a positive predictor of mastery-approach goals and mastery-avoidance goals (without and, in Study 2b, with SDE controlled). These findings highlight the value of conceptualising and utilising IM as a personality variable in its own right and shed light on the nature of the achievement motive and achievement goal constructs. © 2016 International Union of Psychological Science.

Independent Predictors of Prognosis Based on Oral Cavity Squamous Cell Carcinoma Surgical Margins.

PubMed

Buchakjian, Marisa R; Ginader, Timothy; Tasche, Kendall K; Pagedar, Nitin A; Smith, Brian J; Sperry, Steven M

2018-05-01

Objective To conduct a multivariate analysis of a large cohort of oral cavity squamous cell carcinoma (OCSCC) cases for independent predictors of local recurrence (LR) and overall survival (OS), with emphasis on the relationship between (1) prognosis and (2) main specimen permanent margins and intraoperative tumor bed frozen margins. Study Design Retrospective cohort study. Setting Tertiary academic head and neck cancer program. Subjects and Methods This study included 426 patients treated with OCSCC resection between 2005 and 2014 at University of Iowa Hospitals and Clinics. Patients underwent excision of OCSCC with intraoperative tumor bed frozen margin sampling and main specimen permanent margin assessment. Multivariate analysis of the data set to predict LR and OS was performed. Results Independent predictors of LR included nodal involvement, histologic grade, and main specimen permanent margin status. Specifically, the presence of a positive margin (odds ratio, 6.21; 95% CI, 3.3-11.9) or <1-mm/carcinoma in situ margin (odds ratio, 2.41; 95% CI, 1.19-4.87) on the main specimen was an independent predictor of LR, whereas intraoperative tumor bed margins were not predictive of LR on multivariate analysis. Similarly, independent predictors of OS on multivariate analysis included nodal involvement, extracapsular extension, and a positive main specimen margin. Tumor bed margins did not independently predict OS. Conclusion The main specimen margin is a strong independent predictor of LR and OS on multivariate analysis. Intraoperative tumor bed frozen margins do not independently predict prognosis. We conclude that emphasis should be placed on evaluating the main specimen margins when estimating prognosis after OCSCC resection.

Development of a fine thermocouple-needle system for real-time feedback of thermal tumour ablation margin

PubMed Central

Ishizaka, H; Shiraishi, A; Awata, S; Shimizu, A; Hirasawa, S

2011-01-01

Thermal tumour ablation techniques such as radiofrequency (RF) ablation are applied for radical removal of local tumours as an easier, less invasive alternative to surgical resection. A serious drawback of thermal ablation, however, is that the ablation area cannot be accurately assessed during the procedure. To achieve real-time feedback and exact and safe ablation, a superfine thermocouple-needle system (TNS) comprising a 0.25-mm diameter thermocouple embedded in a 22-G, 15-cm-long needle was devised and efficacy was tested in vitro using porcine livers (n = 15) and in vivo using rabbit back muscles (n = 2) and livers (n = 3). A 17-gauge RF electrode with a 2 cm active tip was used for ablation. The TNS was inserted 1 cm from the active tip of the RF electrode and liver temperature around the electrode was measured concurrently. The RF current was cut off when the temperature reached 60°C or after 5 min at ≥50°C. Porcine livers and rabbit back muscles were then cut along a plane passing through the axes of the electrode and the TNS. In rabbit livers, contrast-enhanced CT was performed to evaluate ablation areas. Ablation areas in cut surfaces of porcine livers exhibited well-defined discoloured regions and the TNS tip precisely pinpointed the margin of the ablation area. Contrast-enhanced CT of rabbit livers showed the TNS tip accurately located at the margin of areas without contrast enhancement. These results indicate that the TNS can accurately show ablation margins and that placing the TNS tip at the intended ablation margin permits exact thermal ablation. PMID:21937618

Local control of brain metastases by stereotactic radiosurgery in relation to dose to the tumor margin.

PubMed

Vogelbaum, Michael A; Angelov, Lilyana; Lee, Shih-Yuan; Li, Liang; Barnett, Gene H; Suh, John H

2006-06-01

The maximal tolerated dose (MTD) for stereotactic radiosurgery (SRS) for brain tumors was established by the Radiation Therapy Oncology Group (RTOG) in protocol 90-05, which defined three dose groups based on the maximal tumor diameter. The goal in this retrospective study was to determine whether differences in doses to the margins of brain metastases affect the ability of SRS to achieve local control. Between 1997 and 2003, 202 patients harboring 375 tumors that met study entry criteria underwent SRS for treatment of one or multiple brain metastases. The median overall follow-up duration was 10.7 months (range 3-83 months). A dose of 24 Gy to the tumor margin had a significantly lower risk of local failure than 15 or 18 Gy (p = 0.0005; hazard ratio 0.277, confidence interval [CI] 0.134-0.573), whereas the 15- and 18-Gy groups were not significantly different from each other (p = 0.82) in this regard. The 1-year local control rate was 85% (95% CI 78-92%) in tumors treated with 24 Gy, compared with 49% (CI 30-68%) in tumors treated with 18 Gy and 45% (CI 23-67%) in tumors treated with 15 Gy. Overall patient survival was independent of dose to the tumor margin. Use of the RTOG 90-05 dosing scheme for brain metastases is associated with a variable local control rate. Tumors larger than 2 cm are less effectively controlled than smaller lesions, which can be safely treated with 24 Gy. Prospective evaluations of the relationship between dose to the tumor margin and local control should be performed to confirm these observations.

Small cell lymphocytic variant of marginal zone lymphoma: A distinct form of marginal zone lymphoma derived from naïve B cells as a cutaneous counterpart to the naïve marginal zone lymphoma of splenic origin.

PubMed

Magro, Cynthia M; Olson, Luke C

2018-02-21

Primary cutaneous marginal zone lymphoma most commonly represents an indolent form of cutaneous B cell lymphoma. However, epidermotropic marginal zone lymphoma, blastic marginal zone lymphoma and B cell dominant variants without isotype switching can be associated with extracutaneous dissemination. The presumptive cell of origin is a post germinal center B cell with plasmacytic features. In the extracutaneous setting, however, a naïve B cell origin has been proposed for a subset of marginal zone lymphomas, notably splenic marginal zone lymphoma. The author encountered 11 cases of atypical lymphocytic infiltration of the skin primarily occurring in older individuals with an upper arm and head and neck localization; there was a reproducible pattern of diffuse and nodular infiltration by small monomorphic-appearing B cells. Phenotypically, the infiltrate was one predominated by B cells exhibiting CD23 and IgD positivity without immunoreactivity for CD38 and there were either no plasma cells or only a few without light chain restriction. In cases presenting with a solitary lesion complete excision and/or radiation led to successful disease remission in all cases without recurrence or metastatic disease. Of three cases with multiple initial lesions, evidence of extracutaneous disease was seen in two cases and recurrence occurred in one case. No patients have died of lymphoma. Longer term follows up and additional cases are needed to determine if this subset of marginal zone lymphoma is associated with a worse prognosis. Copyright © 2018. Published by Elsevier Inc.

Deep sea sedimentation processes and geomorphology: Northwest Atlantic continental margin

NASA Astrophysics Data System (ADS)

Mosher, David; Campbell, Calvin; Gardner, Jim; Chaytor, Jason; Piper, David; Rebesco, Michele

2017-04-01

Deep-sea sedimentation processes impart a fundamental control on the morphology of the western North Atlantic continental margin from Blake Spur to Hudson Strait. This fact is illustrated by the variable patterns of cross-margin gradients that are based on extensive new multibeam echo-sounder data informed by subbottom profiler and seismic reflection data. Erosion by off-shelf sediment transport in turbidity currents creates gullies, canyons and channels and a steep upper slope. Amalgamation of these conduits produces singular channels and turbidite fan complexes on the lower slope, flattening slope-profile gradients. The effect is an exponentially decaying "graded" slope profile. Comparatively, sediment mass failure produces steeper upper slopes due to head scarp development and a wedging architecture to the lower slope as deposits thin in the downslope direction. This process results in either a "stepped" slope, and/or a significant downslope gradient change where MTDs pinch out. Large drift deposits created by geostrophic currents are developed all along the margin. Blake Ridge, Sackville Spur, and Hamilton Spur are large detached drifts on disparate parts of the margin. They form a linear "above grade" profile along their crests from the shelf to abyssal plain. Deeper portions of the US continental margin are dominated by the Chesapeake Drift and Hatteras Outer Ridge; both plastered elongate mounded drifts. Farther north, particularly on the Grand Banks margin, are plastered and separated drifts. These drifts form "stepped" slope profiles, where they onlap the margin. Trough-mouth fan complexes become more common along the margin with increasing latitude. Sediment deposition and retention, particularly those dominated by glacigenic debris flows, characterize these segments producing an "above grade" slope profile. Understanding these geomorphological consequences of deep sea sedimentation processes is important to extended continental shelf mapping in which

Marginal cost curves for water footprint reduction in irrigated agriculture: a policy and decision making guide for efficient water use in crop production

NASA Astrophysics Data System (ADS)