Sample records for marginal increment analysis

  1. Product Quality Modelling Based on Incremental Support Vector Machine

    NASA Astrophysics Data System (ADS)

    Wang, J.; Zhang, W.; Qin, B.; Shi, W.

    2012-05-01

    Incremental Support vector machine (ISVM) is a new learning method developed in recent years based on the foundations of statistical learning theory. It is suitable for the problem of sequentially arriving field data and has been widely used for product quality prediction and production process optimization. However, the traditional ISVM learning does not consider the quality of the incremental data which may contain noise and redundant data; it will affect the learning speed and accuracy to a great extent. In order to improve SVM training speed and accuracy, a modified incremental support vector machine (MISVM) is proposed in this paper. Firstly, the margin vectors are extracted according to the Karush-Kuhn-Tucker (KKT) condition; then the distance from the margin vectors to the final decision hyperplane is calculated to evaluate the importance of margin vectors, where the margin vectors are removed while their distance exceed the specified value; finally, the original SVs and remaining margin vectors are used to update the SVM. The proposed MISVM can not only eliminate the unimportant samples such as noise samples, but also can preserve the important samples. The MISVM has been experimented on two public data and one field data of zinc coating weight in strip hot-dip galvanizing, and the results shows that the proposed method can improve the prediction accuracy and the training speed effectively. Furthermore, it can provide the necessary decision supports and analysis tools for auto control of product quality, and also can extend to other process industries, such as chemical process and manufacturing process.

  2. Program budgeting and marginal analysis: a case study in chronic airflow limitation.

    PubMed

    Crockett, A; Cranston, J; Moss, J; Scown, P; Mooney, G; Alpers, J

    1999-01-01

    Program budgeting and marginal analysis is a method of priority-setting in health care. This article describes how this method was applied to the management of a disease-specific group, chronic airflow limitation. A sub-program flow chart clarified the major cost drivers. After assessment of the technical efficiency of the sub-programs and careful and detailed analysis, incremental and decremental wish lists of activities were established. Program budgeting and marginal analysis provides a framework for rational resource allocation. The nurturing of a vigorous program management group, with members representing all participants in the process (including patients/consumers), is the key to a successful outcome.

  3. Craniocaudal Safety Margin Calculation Based on Interfractional Changes in Tumor Motion in Lung SBRT Assessed With an EPID in Cine Mode

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

    Ueda, Yoshihiro, E-mail: ueda-yo@mc.pref.osaka.jp; Miyazaki, Masayoshi; Nishiyama, Kinji

    2012-07-01

    Purpose: To evaluate setup error and interfractional changes in tumor motion magnitude using an electric portal imaging device in cine mode (EPID cine) during the course of stereotactic body radiation therapy (SBRT) for non-small-cell lung cancer (NSCLC) and to calculate margins to compensate for these variations. Materials and Methods: Subjects were 28 patients with Stage I NSCLC who underwent SBRT. Respiratory-correlated four-dimensional computed tomography (4D-CT) at simulation was binned into 10 respiratory phases, which provided average intensity projection CT data sets (AIP). On 4D-CT, peak-to-peak motion of the tumor (M-4DCT) in the craniocaudal direction was assessed and the tumor centermore » (mean tumor position [MTP]) of the AIP (MTP-4DCT) was determined. At treatment, the tumor on cone beam CT was registered to that on AIP for patient setup. During three sessions of irradiation, peak-to-peak motion of the tumor (M-cine) and the mean tumor position (MTP-cine) were obtained using EPID cine and in-house software. Based on changes in tumor motion magnitude ( Increment M) and patient setup error ( Increment MTP), defined as differences between M-4DCT and M-cine and between MTP-4DCT and MTP-cine, a margin to compensate for these variations was calculated with Stroom's formula. Results: The means ({+-}standard deviation: SD) of M-4DCT and M-cine were 3.1 ({+-}3.4) and 4.0 ({+-}3.6) mm, respectively. The means ({+-}SD) of Increment M and Increment MTP were 0.9 ({+-}1.3) and 0.2 ({+-}2.4) mm, respectively. Internal target volume-planning target volume (ITV-PTV) margins to compensate for Increment M, Increment MTP, and both combined were 3.7, 5.2, and 6.4 mm, respectively. Conclusion: EPID cine is a useful modality for assessing interfractional variations of tumor motion. The ITV-PTV margins to compensate for these variations can be calculated.« less

  4. 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 margins. At each time point, the system was linearized about the current operating point using Simulink's built-in solver. Each linearized system in time was evaluated for its rigid-body gain margin (high frequency gain margin), rigid-body phase margin, and aero gain margin (low frequency gain margin) for each control axis. Using the stability margins derived from the baseline linearization approach, the time domain derived stability margins were determined by executing time domain simulations in which axis-specific incremental gain and phase adjustments were made to the nominal system about the expected neutral stability point at specific flight times. The baseline stability margin time histories were used to shift the system gain to various values around the zero margin point such that a precise amount of expected gain margin was maintained throughout flight. When assessing the gain margins, the gain was applied starting at the time point under consideration, thereafter following the variation in the margin found in the linear analysis. When assessing the rigid-body phase margin, a constant time delay was applied to the system starting at the time point under consideration. If the baseline stability margins were correctly determined via the linear analysis, the time domain simulation results should contain unstable behavior at certain gain and phase values. Examples will be shown from repeated simulations with variable added gain and phase lag. Faithfulness of margins calculated from the linear analysis to the nonlinear system will be demonstrated.

  5. 41 CFR 302-17.5 - Definitions and discussion of terms.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    .... (See § 302-17.8(d).) (i) Marginal tax rate (MTR). The tax rate (for example, 33 percent) applicable to a specific increment of income. The Federal, Puerto Rico, and State marginal tax rates to be used in...) for instructions on local marginal tax rate determinations.) (j) Combined marginal tax rate (CMTR). A...

  6. Effect of the insertion and polymerization technique in composite resin restorations: analysis of marginal gap by atomic force microscopy.

    PubMed

    da Silva, Marcos Aurélio Bomfim; de Oliveira, Guilherme José Pimentel Lopes; Tonholo, Josealdo; Júnior, José Ginaldo da Silva; Santos, Lucineide de Melo; Dos Reis, José Ivo Limeira

    2010-12-01

    This in vitro study evaluated the marginal gap at the composite tooth/resin interface in class V cavities under the influence of two insertion techniques and a curing system by means of atomic force microscopy (AFM). Forty enamel and dentin cavities were prepared on the buccal surface in bovine teeth with quadratic forms measuring 2 mm × 2 mm and depth of 1.5 mm. The teeth were then divided into four groups: group A, 10 cavities were restored in one increment, light cured by halogen light; group B, 10 cavities filled with bulk filling, light cured by the light emitting diodes (LED); group C, 10 cavities were restored by the incremental technique, light cured by halogen light; group D, 10 cavities were restored by the incremental technique, light cured by the LED. The teeth underwent the polishing procedure and were analyzed by AFM for tooth/restoration interface evaluation. The data were compared between groups using the nonparametric Kruskall-Wallis and Mann-Whitney tests (p < 0.05). The results showed a statistically significant difference between groups A and B and groups A and C. It was concluded that no insertion and polymerization technique was able to completely seal the cavity.

  7. Modeling the temporal periodicity of growth increments based on harmonic functions

    PubMed Central

    Morales-Bojórquez, Enrique; González-Peláez, Sergio Scarry; Bautista-Romero, J. Jesús; Lluch-Cota, Daniel Bernardo

    2018-01-01

    Age estimation methods based on hard structures require a process of validation to confirm the periodical pattern of growth marks. Among such processes, one of the most used is the marginal increment ratio (MIR), which was stated to follow a sinusoidal cycle in a population. Despite its utility, in most cases, its implementation has lacked robust statistical analysis. Accordingly, we propose a modeling approach for the temporal periodicity of growth increments based on single and second order harmonic functions. For illustrative purposes, the MIR periodicities for two geoduck species (Panopea generosa and Panopea globosa) were modeled to identify the periodical pattern of growth increments in the shell. This model identified an annual periodicity for both species but described different temporal patterns. The proposed procedure can be broadly used to objectively define the timing of the peak, the degree of symmetry, and therefore, the synchrony of band deposition of different species on the basis of MIR data. PMID:29694381

  8. The Marginal Costs of Instruction.

    ERIC Educational Resources Information Center

    Hoenack, Stephen A.; And Others

    1986-01-01

    A study of instructional costs in a large university focuses on graduate education, draws inferences about the economic costs of incremental or marginal enrollments, and examines how the costs facing faculty differ from those incurred by the administration and the state legislature. (MSE)

  9. Operational and financial impact of physician screening in the ED.

    PubMed

    Soremekun, Olanrewaju A; Biddinger, Paul D; White, Benjamin A; Sinclair, Julia R; Chang, Yuchiao; Carignan, Sarah B; Brown, David F M

    2012-05-01

    Physician screening is one of many front-end interventions being implemented to improve emergency department (ED) efficiency. We aimed to quantify the operational and financial impact of this intervention at an urban tertiary academic center. We conducted a 2-year before-after analysis of a physician screening system at an urban tertiary academic center with 90 000 annual visits. Financial impact consisted of the ED and inpatient revenue generated from the incremental capacity and the reduction in left without being seen (LWBS) rates. The ED and inpatient margin contribution as well as capital expenditure were based on available published data. We summarized the financial impact using net present value of future cash flows performing sensitivity analysis on the assumptions. Operational outcome measures were ED length of stay and percentage of LWBS. During the first year, we estimate the contribution margin of the screening system to be $2.71 million and the incremental operational cost to be $1.86 million. Estimated capital expenditure for the system was $1 200 000. The NPV of this investment was $2.82 million, and time to break even from the initial investment was 13 months. Operationally, despite a 16.7% increase in patient volume and no decrease in boarding hours, there was a 7.4% decrease in ED length of stay and a reduction in LWBS from 3.3% to 1.8%. In addition to improving operational measures, the implementation of a physician screening program in the ED allowed for an incremental increase in patient care capacity leading to an overall positive financial impact. Copyright © 2012 Elsevier Inc. All rights reserved.

  10. [Medical and economic evaluation of donated blood screening for hepatitis C and non-A, non-B, non-C hepatitis].

    PubMed

    Vergnon, P; Colin, C; Jullien, A M; Bory, E; Excoffier, S; Matillon, Y; Trepo, C

    1996-01-01

    The aim of this study was to evaluate the cost of hepatitis C and non-A non-B non-C screening strategy in donated blood, currently used in French transfusion centres and to assess the effect in the blood transfusion centres according to the prevalence of the disease and the intrinsec values of tests. This screening strategy was based on alanine aminotransferase assay, and HBc and HCV antibodies detection. In 1993, a survey was conducted in 26 French transfusion centers to estimate the costs of the screening strategy currently used. Average expenditure on diagnostic sets, equipment, staff and administration charges for hepatitis C and non-A non-B non-C screening were calculated. From these results, we estimated the cost of the previous strategy which did not involve HCV antibody testing, so as to determine the incremental cost between the two strategies. We used clinical decision analysis and sensitivity analysis to estimate the incremental cost-effectiveness ratio with data gathered from the literature and examine the impact on blood transfusion centre. Implemented for 100,000 volunteer blood donations, the incremental cost of the new strategy was FF 2,566,111 (1992) and the marginal effectiveness was 180 additional infected donations detected. The sensitivity analysis showed the major influence of infection prevalence in donated blood on the incremental cost-effectiveness ratio: the lower the prevalence, the higher the cost-effectiveness ratio per contaminated blood product avoided.

  11. In vitro assessment of polymerization procedures in Class II restorations: sealing, FTIR, and microhardness evaluations.

    PubMed

    Tassery, H; de Donato, P; Barrès, O; Déjou, J

    2001-01-01

    This study was undertaken to evaluate several polymerization and filling procedures (incremental, bulk, light-tip, soft-cured, plasma devices) in Class II restorations through (1) a sealing evaluation of restorations filled with Tetric Ceram (TC) and Bisfil 2B (B2B, self-cured composite used as a control), (2) a FTIR analysis measuring the variations of the degree of conversion in terms of area unit ratio of the relevant resin composites and (3) a microhardness test to corroborate the FTIR analysis. The length of the tracer penetration was measured from the gingival margin up to the cavity wall with an episcope on sectioned teeth. A ceramic mould, simulating a Class II, was filled according to the different groups and the samples were analyzed with a Bruker IFS 55 spectrometer on ultrathin sections (3 mu). The results were analyzed in terms of area unit ratio and total exposed energy. Under the same conditions, a microhardness test was run with a Frank Weihem machine. The results of the sealing evaluation for light-tip, incremental and self-cured techniques did not differ. The plasma procedure failed in this evaluation as the bottom increment was not polymerized. The smallest area unit ratio (the best degree of conversion) was observed in 2 groups: one, the combination of the light-tip and soft process, and two, the self-cured resin composite (B2B). The distance at which the plasma procedure failed to cure the resin composite was between 3.5 and 4.5 mm. The microhardness test confirmed the FTIR analysis except for the group G2 (TC + light-tip). As also shown by FTIR analysis, no difference between the two relevant levels was observed with the hardness test. The dentin marginal sealing efficiency of Tetric Ceram restorations was increased with the light-tip technique, but was not better than the self-cured resin composite (B2B). For Tetric Ceram, the combination of the light-tip and soft process leads to a higher degree of conversion than the other groups. There is no linear relationship between the degree of conversion, the microhardness and the total exposed energy. The combination of the soft polymerization and the light-tip device might be an alternative restorative technique to the current incremental technique.

  12. Incremental Criterion Validity of the WJ-III COG Clinical Clusters: Marginal Predictive Effects beyond the General Factor

    ERIC Educational Resources Information Center

    McGill, Ryan J.

    2015-01-01

    The current study examined the incremental validity of the clinical clusters from the Woodcock-Johnson III Tests of Cognitive Abilities (WJ-III COG) for predicting scores on the Woodcock-Johnson III Tests of Achievement (WJ-III ACH). All participants were children and adolescents (N = 4,722) drawn from the nationally representative WJ-III…

  13. Marginal Emissions Factors for Electricity Generation in the Midcontinent ISO.

    PubMed

    Thind, Maninder P S; Wilson, Elizabeth J; Azevedo, Inês L; Marshall, Julian D

    2017-12-19

    Environmental consequences of electricity generation are often determined using average emission factors. However, as different interventions are incrementally pursued in electricity systems, the resulting marginal change in emissions may differ from what one would predict based on system-average conditions. Here, we estimate average emission factors and marginal emission factors for CO 2 , SO 2 , and NO x from fossil and nonfossil generators in the Midcontinent Independent System Operator (MISO) region during years 2007-2016. We analyze multiple spatial scales (all MISO; each of the 11 MISO states; each utility; each generator) and use MISO data to characterize differences between the two emission factors (average; marginal). We also explore temporal trends in emissions factors by hour, day, month, and year, as well as the differences that arise from including only fossil generators versus total generation. We find, for example, that marginal emission factors are generally higher during late-night and early morning compared to afternoons. Overall, in MISO, average emission factors are generally higher than marginal estimates (typical difference: ∼20%). This means that the true environmental benefit of an energy efficiency program may be ∼20% smaller than anticipated if one were to use average emissions factors. Our analysis can usefully be extended to other regions to support effective near-term technical, policy and investment decisions based on marginal rather than only average emission factors.

  14. Avoided electricity subsidy payments can finance substantial appliance efficiency incentive programs: Case study of Mexico

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

    Leventis, Greg; Gopal, Anand; Rue du Can, Stephane de la

    Numerous countries use taxpayer funds to subsidize residential electricity for a variety of socioeconomic objectives. These subsidies lower the value of energy efficiency to the consumer while raising it for the government. Further, while it would be especially helpful to have stringent Minimum Energy Performance Standards (MEPS) for appliances and buildings in this environment, they are hard to strengthen without imposing a cost on ratepayers. In this secondbest world, where the presence of subsidies limits the government’s ability to strengthen standards, we find that avoided subsidies are a readily available source of financing for energy efficiency incentive programs. Here, wemore » introduce the LBNL Energy Efficiency Revenue Analysis (LEERA) model to estimate the appliance efficiency improvements that can be achieved in Mexico by the revenue neutral financing of incentive programs from avoided subsidy payments. LEERA uses the detailed techno-economic analysis developed by LBNL for the Super-efficient Equipment and Appliance Deployment (SEAD) Initiative to calculate the incremental costs of appliance efficiency improvements. We analyze Mexico’s tariff structures and the long-run marginal cost of supply to calculate the marginal savings for the government from appliance efficiency. We find that avoided subsidy payments alone can finance incentive programs that cover the full incremental cost of refrigerators that are 27% more efficient and TVs that are 32% more efficient than baseline models. We find less substantial market transformation potential for room ACs primarily because AC energy savings occur at less subsidized tariffs.« less

  15. Economic analysis: randomized placebo-controlled clinical trial of erlotinib in advanced non-small cell lung cancer.

    PubMed

    Bradbury, Penelope A; Tu, Dongsheng; Seymour, Lesley; Isogai, Pierre K; Zhu, Liting; Ng, Raymond; Mittmann, Nicole; Tsao, Ming-Sound; Evans, William K; Shepherd, Frances A; Leighl, Natasha B

    2010-03-03

    The NCIC Clinical Trials Group conducted the BR.21 trial, a randomized placebo-controlled trial of erlotinib (an epidermal growth factor receptor tyrosine kinase inhibitor) in patients with previously treated advanced non-small cell lung cancer. This trial accrued patients between August 14, 2001, and January 31, 2003, and found that overall survival and quality of life were improved in the erlotinib arm than in the placebo arm. However, funding restrictions limit access to erlotinib in many countries. We undertook an economic analysis of erlotinib treatment in this trial and explored different molecular and clinical predictors of outcome to determine the cost-effectiveness of treating various populations with erlotinib. Resource utilization was determined from individual patient data in the BR.21 trial database. The trial recruited 731 patients (488 in the erlotinib arm and 243 in the placebo arm). Costs arising from erlotinib treatment, diagnostic tests, outpatient visits, acute hospitalization, adverse events, lung cancer-related concomitant medications, transfusions, and radiation therapy were captured. The incremental cost-effectiveness ratio was calculated as the ratio of incremental cost (in 2007 Canadian dollars) to incremental effectiveness (life-years gained). In exploratory analyses, we evaluated the benefits of treatment in selected subgroups to determine the impact on the incremental cost-effectiveness ratio. The incremental cost-effectiveness ratio for erlotinib treatment in the BR.21 trial population was $94,638 per life-year gained (95% confidence interval = $52,359 to $429,148). The major drivers of cost-effectiveness included the magnitude of survival benefit and erlotinib cost. Subgroup analyses revealed that erlotinib may be more cost-effective in never-smokers or patients with high EGFR gene copy number. With an incremental cost-effectiveness ratio of $94 638 per life-year gained, erlotinib treatment for patients with previously treated advanced non-small cell lung cancer is marginally cost-effective. The use of molecular predictors of benefit for targeted agents may help identify more or less cost-effective subgroups for treatment.

  16. Preliminary Evaluation of a Regional Atmospheric Chemical Data Assimilation System for Environmental Surveillance

    PubMed Central

    Lee, Pius; Liu, Yang

    2014-01-01

    We report the progress of an ongoing effort by the Air Resources Laboratory, NOAA to build a prototype regional Chemical Analysis System (ARLCAS). The ARLCAS focuses on providing long-term analysis of the three dimensional (3D) air-pollutant concentration fields over the continental U.S. It leverages expertise from the NASA Earth Science Division-sponsored Air Quality Applied Science Team (AQAST) for the state-of-science knowledge in atmospheric and data assimilation sciences. The ARLCAS complies with national operational center requirement protocols and aims to have the modeling system to be maintained by a national center. Meteorology and chemistry observations consist of land-, air- and space-based observed and quality-assured data. We develop modularized testing to investigate the efficacies of the various components of the ARLCAS. The sensitivity testing of data assimilation schemes showed that with the increment of additional observational data sets, the accuracy of the analysis chemical fields also increased incrementally in varying margins. The benefit is especially noted for additional data sets based on a different platform and/or a different retrieval algorithm. We also described a plan to apply the analysis chemical fields in environmental surveillance at the Centers for Disease Control and Prevention. PMID:25514141

  17. Preliminary evaluation of a regional atmospheric chemical data assimilation system for environmental surveillance.

    PubMed

    Lee, Pius; Liu, Yang

    2014-12-01

    We report the progress of an ongoing effort by the Air Resources Laboratory, NOAA to build a prototype regional Chemical Analysis System (ARLCAS). The ARLCAS focuses on providing long-term analysis of the three dimensional (3D) air-pollutant concentration fields over the continental U.S. It leverages expertise from the NASA Earth Science Division-sponsored Air Quality Applied Science Team (AQAST) for the state-of-science knowledge in atmospheric and data assimilation sciences. The ARLCAS complies with national operational center requirement protocols and aims to have the modeling system to be maintained by a national center. Meteorology and chemistry observations consist of land-, air- and space-based observed and quality-assured data. We develop modularized testing to investigate the efficacies of the various components of the ARLCAS. The sensitivity testing of data assimilation schemes showed that with the increment of additional observational data sets, the accuracy of the analysis chemical fields also increased incrementally in varying margins. The benefit is especially noted for additional data sets based on a different platform and/or a different retrieval algorithm. We also described a plan to apply the analysis chemical fields in environmental surveillance at the Centers for Disease Control and Prevention.

  18. Imaging Analysis of Hepatoblastoma Resectability Across Neoadjuvant Chemotherapy

    PubMed Central

    Murphy, Andrew J.; Ayers, Gregory D.; Hilmes, Melissa A.; Mukherjee, Kaushik; Wilson, Kevin J.; Allen, Wade M.; Fernandez-Pineda, Israel; Shinall, Myrick C.; Zhao, Zhiguo; Furman, Wayne L.; McCarville, Mary Beth; Davidoff, Andrew M.; Lovvorn, Harold N.

    2013-01-01

    Purpose Hepatoblastomas often require neoadjuvant chemotherapy to facilitate partial hepatectomy, which necessitates freedom of tumor borders from the confluence of hepatic veins (COHV), portal vein bifurcation (PVB), and retrohepatic inferior vena cava (IVC). This study aimed to clarify the effect of incremental neoadjuvant cycles on the AHEP0731 protocol criteria of hepatoblastoma resectability. Methods Hepatoblastoma responses to neoadjuvant chemotherapy were analyzed among patients (n=23) treated at two children’s hospitals between 1996 and 2010. Using digital imaging data, ellipsoid and point-based models were created to measure tumor volume regression and respective distances from tumor borders nearest to the COHV, PVB, and IVC. Results Hepatoblastoma volumes regressed with incremental neoadjuvant chemotherapy cycles (p<0.001). Although tumor borders regressed away from the COHV (p=0.008), on average only 1.1mm was gained. No change from tumor borders to the PVB was detected (p=0.102). Distances from tumor borders to the IVC remained stable at one hospital (p=0.612), but increased only 0.15mm every 10 days of therapy at the other (p=0.002). Neoadjuvant chemotherapy induced slightly more tumors to meet the threshold vascular margin of 1cm (baseline to completion): COHV, 11 (47.8%) to 17 (73.9%; p=0.058); PVB, 11 (47.8%) to 15 (65.2%; p=0.157); IVC, 4 (17.4%) to 10 (43.5%; p=0.034). No differences were detected in demographic or disease-specific characteristics between patients who did or did not achieve this 1cm margin after conclusion of chemotherapy. Conclusion Hepatoblastoma volumes regress significantly with increasing neoadjuvant chemotherapy cycles. However, tumors often remain anchored to the major hepatic vasculature, showing marginal improvement in resectability criteria. PMID:23845613

  19. Modeling and Analysis of Wholesale Electricity Market Design. Understanding the Missing Money Problem. December 2013 - January 2015

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

    Papalexopoulos, A.; Hansen, C.; Perrino, D.

    This project examined the impact of renewable energy sources, which have zero incremental energy costs, on the sustainability of conventional generation. This “missing money” problem refers to market outcomes in which infra-marginal energy revenues in excess of operations and maintenance (O&M) costs are systematically lower than the amortized costs of new entry for a marginal generator. The problem is caused by two related factors: (1) conventional generation is dispatched less, and (2) the price that conventional generation receives for its energy is lower. This lower revenue stream may not be sufficient to cover both the variable and fixed costs ofmore » conventional generation. In fact, this study showed that higher wind penetrations in the Electric Reliability Council of Texas (ERCOT) system could cause many conventional generators to become uneconomic.« less

  20. Geographical and epidemiological analysis of oncological incidence in paediatric and adolescent ages in a municipality of North-Western Italy: Vercelli, years 2002-2009.

    PubMed

    Salerno, C; Berchialla, P; Palin, L A; Barasolo, E; Fossale, P G; Marciani, P

    2017-01-01

    This study of the geographical incidence on the oncological mortality in young age (0-44 years) in the City of Vercelli, was aimed to address the concerns of the population and the request of municipal administrators. A detailed and sophisticated study for a City of medium-small size is due for the presence of various sources of pressure, such as a MSW incinerator just a few kilometres from the city and an intensive agricultural activity that characterizes the entire area. The study is based on the census analysis of the population, and of the hospital admission cards, and it considers epidemiological standardized estimators and spatial analysis through Bayesian models, as well. Both approaches highlight Major risks for the area south of the city for major tumours such as total cancer in women (SIR / SMR significant excess of about 50%), colorectal (mean increments SMR / SIR between 3 and 4 times), ovary (mean increments SMR / SIR between 3:04 and times), and nervous system (increases 3 times for both indicators). These results deserve further studies through inferential case-control and cohort analysis, given the marginal role of the possible occupational hazards in the aetiology of juvenile cancer disorders.

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

    Ronald J. MacDonald; Charles M. Boyer; Joseph H. Frantz Jr

    Stripper gas and oil well operators frequently face a dilemma regarding maximizing production from low-productivity wells. With thousands of stripper wells in the United States covering extensive acreage, it is difficult to identify easily and efficiently marginal or underperforming wells. In addition, the magnitude of reviewing vast amounts of data places a strain on an operator's work force and financial resources. Schlumberger DCS, in cooperation with the National Energy Technology Laboratory (NETL) and the U.S. Department of Energy (DOE), has created software and developed in-house analysis methods to identify remediation potential in stripper wells relatively easily. This software is referredmore » to as Stripper Well Analysis Remediation Methodology (SWARM). SWARM was beta-tested with data pertaining to two gas fields located in northwestern Pennsylvania and had notable results. Great Lakes Energy Partners, LLC (Great Lakes) and Belden & Blake Corporation (B&B) both operate wells in the first field studied. They provided data for 729 wells, and we estimated that 41 wells were candidates for remediation. However, for reasons unbeknownst to Schlumberger these wells were not budgeted for rework by the operators. The second field (Cooperstown) is located in Crawford, Venango, and Warren counties, Pa and has more than 2,200 wells operated by Great Lakes. This paper discusses in depth the successful results of a candidate recognition study of this area. We compared each well's historical production with that of its offsets and identified 339 underperformers before considering remediation costs, and 168 economically viable candidates based on restimulation costs of $50,000 per well. From this data, we prioritized a list based on the expected incremental recoverable gas and 10% discounted net present value (NPV). For this study, we calculated the incremental gas by subtracting the volumes forecasted after remediation from the production projected at its current configuration. Assuming that remediation efforts increased production from the 168 marginal wells to the average of their respective offsets, approximately 6.4 Bscf of gross incremental gas with a NPV approximating $4.9 million after investment, would be made available to the domestic market. Seventeen wells have successfully been restimulated to date and have already obtained significant production increases. At the time of this report, eight of these wells had enough post-rework production data available to forecast the incremental gas and verify the project's success. This incremental gas is estimated at 615 MMscf. The outcome of the other ten wells will be determined after more post-refrac production data becomes available. Plans are currently underway for future restimulations. The success of this project has shown the value of this methodology to recognize underperforming wells quickly and efficiently in fields containing hundreds or thousands of wells. This contributes considerably to corporate net income and domestic natural gas and/or oil reserves.« less

  2. One Hundred Ways to be Non-Fickian - A Rigorous Multi-Variate Statistical Analysis of Pore-Scale Transport

    NASA Astrophysics Data System (ADS)

    Most, Sebastian; Nowak, Wolfgang; Bijeljic, Branko

    2015-04-01

    Fickian transport in groundwater flow is the exception rather than the rule. Transport in porous media is frequently simulated via particle methods (i.e. particle tracking random walk (PTRW) or continuous time random walk (CTRW)). These methods formulate transport as a stochastic process of particle position increments. At the pore scale, geometry and micro-heterogeneities prohibit the commonly made assumption of independent and normally distributed increments to represent dispersion. Many recent particle methods seek to loosen this assumption. Hence, it is important to get a better understanding of the processes at pore scale. For our analysis we track the positions of 10.000 particles migrating through the pore space over time. The data we use come from micro CT scans of a homogeneous sandstone and encompass about 10 grain sizes. Based on those images we discretize the pore structure and simulate flow at the pore scale based on the Navier-Stokes equation. This flow field realistically describes flow inside the pore space and we do not need to add artificial dispersion during the transport simulation. Next, we use particle tracking random walk and simulate pore-scale transport. Finally, we use the obtained particle trajectories to do a multivariate statistical analysis of the particle motion at the pore scale. Our analysis is based on copulas. Every multivariate joint distribution is a combination of its univariate marginal distributions. The copula represents the dependence structure of those univariate marginals and is therefore useful to observe correlation and non-Gaussian interactions (i.e. non-Fickian transport). The first goal of this analysis is to better understand the validity regions of commonly made assumptions. We are investigating three different transport distances: 1) The distance where the statistical dependence between particle increments can be modelled as an order-one Markov process. This would be the Markovian distance for the process, where the validity of yet-unexplored non-Gaussian-but-Markovian random walks start. 2) The distance where bivariate statistical dependence simplifies to a multi-Gaussian dependence based on simple linear correlation (validity of correlated PTRW/CTRW). 3) The distance of complete statistical independence (validity of classical PTRW/CTRW). The second objective is to reveal characteristic dependencies influencing transport the most. Those dependencies can be very complex. Copulas are highly capable of representing linear dependence as well as non-linear dependence. With that tool we are able to detect persistent characteristics dominating transport even across different scales. The results derived from our experimental data set suggest that there are many more non-Fickian aspects of pore-scale transport than the univariate statistics of longitudinal displacements. Non-Fickianity can also be found in transverse displacements, and in the relations between increments at different time steps. Also, the found dependence is non-linear (i.e. beyond simple correlation) and persists over long distances. Thus, our results strongly support the further refinement of techniques like correlated PTRW or correlated CTRW towards non-linear statistical relations.

  3. 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.

  4. [Evaluating cost/equity in the Colombian health system, 1998-2005].

    PubMed

    Eslava-Schmalbach, Javier; Barón, Gilberto; Gaitán-Duarte, Hernando; Alfonso, Helman; Agudelo, Carlos; Sánchez, Carolina

    2008-01-01

    An economic analysis of cost-equity (from society's viewpoint) for evaluating the impact of Law 100/93 in Colombia between 1998 and 2005. An economic analysis compared costs and equity in health in Colombia between 1998 and 2005. Data was taken from the Colombian Statistics' Administration Department ( Departamento Administrativo Nacional de Estadistica - DANE) and from national demographic and health surveys carried out in 2000 and 2005. Information regarding costs was taken from the National Health Accounts' System. Inequity in Health was considered in line with the Inequity in Health Index (IHI). Incremental and average cost-equity analysis covered three sub-periods; 1998-1999 (during which time per capita gross internal product became reduced in Colombia ), 2000-2001 (during which time total health expense became reduced) and 2001 -2005. An unstable tendency for inequity in health becoming reduced during the period was revealed. There was an inverse relationship between IHI and public health spending and a direct relationship between out-of-pocket spending on health and equity in health (Spearman, p<0.05). The second period had the best incremental cost-equity ratio. Fluctuations in IHI and marginal cost-equity during the periods being analysed suggested that health spending depended on equity in health in Colombia during the period being studied.

  5. Structural development of the onshore Otway passive margin (Australia): the interaction of rotating syn-sedimentary faults

    NASA Astrophysics Data System (ADS)

    Tanner, David C.; Ziesch, Jennifer; Krawczyk, Charlotte M.

    2017-04-01

    Within the context of long-term CO2 storage integrity, we interpreted the faults within the 2.2 km thick, syn-rift, Late Cretaceous to Recent sediments below the CO2CRC Otway Project site in Australia using a detailed interpretation of a 3-D reflection seismic cube (32.3 km×14.35 km × 4100 ms TWT). All the faults in the onshore Otway passive margin basin in this area were active to varying degrees during sedimentation, between ca. 120 and 50 Ma, before they died out. From analysis of fault juxtaposition and fault tip-line propagation maps, as well as analysis of individual stratigraphic thickness maps, we determine the direction and incremental amount of syn-sedimentary movement on each fault. Thickening of the hanging-walls of the faults occurred, as is typical for syn-sedimentary faults. However, we also determine that substantial local footwall thinning took place. Although the syn-sedimentary behaviour of the faults was constantly maintained until 50 Ma, there were two main phases of footwall thinning, separated by a quiescent phase. We postulate that these phases of footwall thinning represent rotation of the fault blocks that correlate with prograding sediment pulses within the passive margin. The rotation of the fault blocks occurred simultaneously, i.e., they could only rotate if they interacted.

  6. 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.

  7. Cognitive Skill and Traditional Trance Hypnotic Inductions: A Within-Subjects Comparison.

    ERIC Educational Resources Information Center

    Vickery, Anne R.; And Others

    1985-01-01

    Compared a traditional trance hypnotic induction and a cognitive skill induction using a within-subjects design with college students (N=40). The skill induction enhanced responses to suggestions and produced marginally significant increments in behavioral responses when preceded by the trance induction, but there were no significant differences…

  8. DETERMINING THE "MARGIN OF INCREMENTAL EXPOSURE": AN APPROACH TO ASSESSING NON-CANCER HEALTH EFFECTS OF DIOXINS

    EPA Science Inventory

    U.S. Environmental Protection Agency (EPA) guidance issued in April 1994 for performing screening level risk analyses of emissions from facilities that burn hazardous waste does not address the evaluation of non-cancer health effects from dioxin emissions. Historically, EPA has ...

  9. Do different vertical positions of maxillary central incisors influence smile esthetics perception?

    PubMed

    Menezes, Erica Bretas Cabral; Bittencourt, Marcos Alan Vieira; Machado, Andre Wilson

    2017-01-01

    The purpose of this study was to determine the perception of smile esthetics among orthodontists and layperson, with respect to different maxillary central incisors vertical positions in full-face and close-up smile analyses. Frontal photographs of the smiles of two adult women were used. Images were altered to create a symmetrical image with the gingival margin levels of the maxillary canines matching the central incisors and a 1.0-mm central-to-lateral incisal step. Later, the images were altered in order to create six different central incisor vertical positions in 0.5-mm increments. The images were randomly assembled in an album, which was given to 114 judges, 57 orthodontists and 57 laypersons, who were asked to evaluate the attractiveness of the images using the visual analog scale. The data collected were statistically analyzed by means of 1-way analysis of variance with the Tukey post-hoc test and the Student t test. The highest rated smiles showed two notable characteristics: a) the central incisor gingival margins matched or were 0.5 mm below the line of the canine gingival margins and; b) the central-to-lateral incisal step was 1.0 to 1.5 mm. The worst smiles showed two notable characteristics: a) the central incisor gingival margins were 1.0 mm above or 1.5 mm below the canine gingival margins and; b) no step between the centrals and laterals or a 2.5-mm step. The vertical position of the maxillary central incisors significantly affected the perception of the smile esthetics, whereas slightly extruded central incisors were more esthetically preferred than intruded.

  10. Cost-effectiveness of a primary care treatment program for depression in low-income women in Santiago, Chile.

    PubMed

    Araya, Ricardo; Flynn, Terry; Rojas, Graciela; Fritsch, Rosemarie; Simon, Greg

    2006-08-01

    The authors compared the incremental cost-effectiveness of a stepped-care, multicomponent program with usual care for the treatment of depressed women in primary care in Santiago, Chile. A cost-effectiveness study was conducted of a previous randomized controlled trial involving 240 eligible women with DSM-IV major depression who were selected from a consecutive sample of adult women attending primary care clinics. The patients were randomly allocated to usual care or a multicomponent stepped-care program led by a nonmedical health care worker. Depression-free days and health care costs derived from local sources were assessed after 3 and 6 months. A health service perspective was used in the economic analysis. Complete data were determined for 80% of the randomly assigned patients. After we adjusted for initial severity, women receiving the stepped-care program had a mean of 50 additional depression-free days over 6 months relative to patients allocated to usual care. The stepped-care program was marginally more expensive than usual care (an extra 216 Chilean pesos per depression-free day). There was a 90% probability that the incremental cost of obtaining an extra depression-free day with the intervention would not exceed 300 pesos (1.04 US dollars). The stepped-care program was significantly more effective and marginally more expensive than usual care for the treatment of depressed women in primary care. Small investments to improve depression appear to yield larger gains in poorer environments. Simple and inexpensive treatment programs tested in developing countries might provide good study models for developed countries.

  11. An Economic Study of the Investment Effects of Education in Agriculture. Final Report.

    ERIC Educational Resources Information Center

    Persons, Edgar A.; And Others

    To determine the absolute economic return to adult farm business management education, the diminishing marginal return effect from added increments of education, and benefit-cost ratio of the educational program for participants and the sponsoring community, data were collected from 3,578 farm business records representing farmers enrolled in farm…

  12. Incremental costs of introducing jet injection technology for delivery of routine childhood vaccinations: comparative analysis from Brazil, India, and South Africa.

    PubMed

    Griffiths, Ulla K; Santos, Andreia C; Nundy, Neeti; Jacoby, Erica; Matthias, Dipika

    2011-01-29

    Disposable-syringe jet injectors (DSJIs) have the potential to deliver vaccines safely and affordably to millions of children around the world. We estimated the incremental costs of transitioning from needles and syringes to delivering childhood vaccines with DSJIs in Brazil, India, and South Africa. Two scenarios were assessed: (1) DSJI delivery of all vaccines at current dose and depth; (2) a change to intradermal (ID) delivery with DSJIs for hepatitis B and yellow fever vaccines, while the other vaccines are delivered by DSJIs at current dose and depth. The main advantage of ID delivery is that only a small fraction of the standard dose may be needed to obtain an immune response similar to that of subcutaneous or intramuscular injection. Cost categories included were vaccines, injection equipment, waste management, and vaccine transport. Some delivery cost items, such as training and personnel were excluded as were treatment cost savings caused by a reduction in diseases transmitted due to unsafe injections. In the standard dose and depth scenario, the incremental costs of introducing DSJIs per fully vaccinated child amount to US$ 0.57 in Brazil, US$ 0.65 in India and US$ 1.24 in South Africa. In the ID scenario, there are cost savings of US$ 0.11 per child in Brazil, and added costs of US$ 0.45 and US$ 0.76 per child in India and South Africa, respectively. The most important incremental cost item is jet injector disposable syringes. The incremental costs should be evaluated against other vaccine delivery technologies that can deliver the same benefits to patients, health care workers, and the community. DSJIs deserve consideration by global and national decision-makers as a means to expand access to ID delivery and to enhance safety at marginal additional cost. Copyright © 2010 Elsevier Ltd. All rights reserved.

  13. Endovascular abdominal aortic aneurysm repair is more profitable than open repair based on contribution margin per day.

    PubMed

    Rosenberg, Barry L; Comstock, Matthew C; Butz, David A; Taheri, Paul A; Williams, David M; Upchurch, Gilbert R

    2005-03-01

    Earlier studies have reported that endovascular abdominal aortic aneurysm (EAAA) repair yields lower total profit margins than open AAA (OAAA) repair. This study compared EAAA versus OAAA based on contribution margin per day, which may better measure profitability of new clinical technologies. Contribution margin equals revenue less variable direct costs (VDCs). VDCs capture incremental resources tied directly to individual patients' activity (eg, invoice price of endograft device, nursing labor). Overhead costs factor into total margin, but not contribution margin. The University of Michigan Health System's cost accounting system was used to extract fiscal year 2002-2003 information on revenue, total margin, contribution margin, and duration of stay for Medicare patients with principal diagnosis of AAA (ICD-9 code 441.4). OAAA had revenues of $37,137 per case versus $28,960 for EAAA, similar VDCs per case, and thus higher contribution margin per case ($24,404 for OAAA vs $13,911 for EAAA, P < .001). However, OAAA had significantly longer mean duration of stay per case (10.2 days vs 2.2 days, P < .001). Therefore, mean contribution margin per day was $2948 for OAAA, but $8569 for EAAA ( P < .001). On the basis of contribution margin per day, EAAA repair dominates OAAA repair. The shorter duration of stay with EAAA allows higher throughput, fuller overhead amortization, better use of scarce inpatient beds, and higher health system profits. Surgeons must understand overhead allocation to devices, especially when new technologies cut duration of stay markedly.

  14. Do different vertical positions of maxillary central incisors influence smile esthetics perception?

    PubMed Central

    Menezes, Erica Bretas Cabral; Bittencourt, Marcos Alan Vieira; Machado, Andre Wilson

    2017-01-01

    ABSTRACT INTRODUCTION: The purpose of this study was to determine the perception of smile esthetics among orthodontists and layperson, with respect to different maxillary central incisors vertical positions in full-face and close-up smile analyses. METHODS: Frontal photographs of the smiles of two adult women were used. Images were altered to create a symmetrical image with the gingival margin levels of the maxillary canines matching the central incisors and a 1.0-mm central-to-lateral incisal step. Later, the images were altered in order to create six different central incisor vertical positions in 0.5-mm increments. The images were randomly assembled in an album, which was given to 114 judges, 57 orthodontists and 57 laypersons, who were asked to evaluate the attractiveness of the images using the visual analog scale. The data collected were statistically analyzed by means of 1-way analysis of variance with the Tukey post-hoc test and the Student t test. RESULTS: The highest rated smiles showed two notable characteristics: a) the central incisor gingival margins matched or were 0.5 mm below the line of the canine gingival margins and; b) the central-to-lateral incisal step was 1.0 to 1.5 mm. The worst smiles showed two notable characteristics: a) the central incisor gingival margins were 1.0 mm above or 1.5 mm below the canine gingival margins and; b) no step between the centrals and laterals or a 2.5-mm step. CONCLUSION: The vertical position of the maxillary central incisors significantly affected the perception of the smile esthetics, whereas slightly extruded central incisors were more esthetically preferred than intruded. PMID:28658361

  15. Influence of the vertical position of maxillary central incisors on the perception of smile esthetics among orthodontists and laypersons.

    PubMed

    Machado, Andre Wilson; McComb, Ryan W; Moon, Won; Gandini, Luiz Gonzaga

    2013-12-01

    The purpose of this study was to determine the perception of smile esthetics among orthodontists and laypeople with respect to different upper central incisor vertical positions in a frontal smile analysis. A frontal close-up smile photo of an adult Caucasian woman was selected. The patient had healthy upper anterior dentition and had no history of orthodontic treatment. Images were altered in order to create six different central incisor vertical positions in 0.5-mm increments. All images were assessed in three different views: full smile, gingival close-up excluding incisal edges, and incisal close-up excluding gingival margins. Images were randomly assembled in an album, which was given to 120 judges: 60 orthodontists and 60 laypersons. Each rater was asked to evaluate the attractiveness of the images using the visual analog scale. The data collected were then statistically analyzed. The highest rated smiles showed two notable characteristics: the central-to-lateral incisal step was 1.5 mm; and the central incisor gingival margins matched the laterals, and both were 0.5 mm below the line of the canine gingival margins. The least attractive smile was the one with no step between the centrals and laterals, and with the central incisor gingival margins 1.0 mm above the canine gingival margins. The results of this study indicate that slightly extruded upper central incisors are more esthetically preferred than intruded. The upper central incisors are the key determinant in evaluating smile esthetics, and thus, the assessment of their ideal vertical positioning is an aspect of paramount importance. © 2013 Wiley Periodicals, Inc.

  16. A new universal simplified adhesive: 18-month clinical evaluation.

    PubMed

    Perdigão, J; Kose, C; Mena-Serrano, A P; De Paula, E A; Tay, L Y; Reis, A; Loguercio, A D

    2014-01-01

    To evaluate the 18-month clinical performance of a multimode adhesive (Scotchbond Universal Adhesive, SU, 3M ESPE, St Paul, MN, USA) in noncarious cervical lesions (NCCLs) using two evaluation criteria. Thirty-nine patients participated in this study. Two-hundred restorations were assigned to four groups: ERm, etch-and-rinse + moist dentin; ERd, etch-and-rinse + dry dentin; Set, selective enamel etching; and SE, self-etch. The composite resin, Filtek Supreme Ultra (3M ESPE), was placed incrementally. The restorations were evaluated at baseline, and at 18 months, using both the World Dental Federation (FDI) and the United States Public Health Service (USPHS) criteria. Statistical analyses were performed using Friedman repeated-measures analysis of variance by rank and McNemar test for significance in each pair (α=0.05). Five restorations (SE: 3; Set: 1; and ERm: 1) were lost after 18 months (p>0.05 for either criteria). Marginal staining occurred in four and 10% of the restorations evaluated (p>0.05), respectively, for USPHS and FDI criteria. Nine restorations were scored as bravo for marginal adaptation using the USPHS criteria and 38%, 40%, 36%, and 44% for groups ERm, ERd, Set, and SE, respectively, when the FDI criteria were applied (p>0.05). However, when semiquantitative scores (or SQUACE) for marginal adaptation were used, SE resulted in a significantly greater number of restorations, with more than 30% of the total length of the interface showing marginal discrepancy (28%) in comparison with the other groups (8%, 6%, and 8%, respectively, for ERm, ERd, and Set). The clinical retention of the multimode adhesive at 18 months does not depend on the bonding strategy. The only differences between strategies were found for the parameter marginal adaptation, for which the FDI criteria were more sensitive than the USPHS criteria.

  17. Risk, Robustness and Water Resources Planning Under Uncertainty

    NASA Astrophysics Data System (ADS)

    Borgomeo, Edoardo; Mortazavi-Naeini, Mohammad; Hall, Jim W.; Guillod, Benoit P.

    2018-03-01

    Risk-based water resources planning is based on the premise that water managers should invest up to the point where the marginal benefit of risk reduction equals the marginal cost of achieving that benefit. However, this cost-benefit approach may not guarantee robustness under uncertain future conditions, for instance under climatic changes. In this paper, we expand risk-based decision analysis to explore possible ways of enhancing robustness in engineered water resources systems under different risk attitudes. Risk is measured as the expected annual cost of water use restrictions, while robustness is interpreted in the decision-theoretic sense as the ability of a water resource system to maintain performance—expressed as a tolerable risk of water use restrictions—under a wide range of possible future conditions. Linking risk attitudes with robustness allows stakeholders to explicitly trade-off incremental increases in robustness with investment costs for a given level of risk. We illustrate the framework through a case study of London's water supply system using state-of-the -art regional climate simulations to inform the estimation of risk and robustness.

  18. Time Domain Stability Margin Assessment Method

    NASA Technical Reports Server (NTRS)

    Clements, Keith

    2017-01-01

    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.

  19. Time-Domain Stability Margin Assessment

    NASA Technical Reports Server (NTRS)

    Clements, Keith

    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.

  20. The marginal cost of public funds with an aging population.

    PubMed

    Wildasin, D E

    1991-05-01

    "As populations in the United States and other advanced economies grow older, the burden of social security and health care financing is expected to rise markedly. Payroll, income, and other taxes on working populations are projected to rise accordingly. The marginal welfare cost to workers of social security and other public expenditures is analyzed within the context of a two-period life cycle model. By relaxing separability assumptions that have become common in the literature, the theoretical structure properly incorporates the effect of these public expenditures on labor supply. Comparative statics results indicate that changing age structure is likely to raise the marginal welfare to workers of social security, education, and other public expenditures. Illustrative calculations for the United States confirm this result, suggesting that the cost to workers of incremental social security benefits may easily double by 2025-2050." excerpt

  1. Techno-Economic Assessment of Recycling BOF Offgas Cleaning System Solid Wastes by Using Zinc-Free Scrap

    NASA Astrophysics Data System (ADS)

    Ma, Naiyang

    High zinc concentration in basic oxygen furnace (BOF) steelmaking offgas (OG) cleaning system solid wastes is one of the main barriers for recycling of the solid wastes in sintering — blast furnace ironmaking process. One of the possible solutions is to utilize zinc-free scrap in BOF steelmaking so that the BOF OG solid wastes will not be contaminated with zinc and can be recycled through sintering — blast furnace ironmaking. This paper describes a model for helping to decide whether to use zinc-free scrap in a BOF process. A model computing marginal price increment of zinc-free scrap is developed. The marginal price increment is proportional to value change of the BOF OG solid wastes after and before using zinc-free scrap, to ratio of BOF solid waste rate to purchased galvanized scrap rate, and to price of galvanized scrap. Due to the variations of consumption rate of purchased galvanized scrap and home galvanized scrap, iron ore price, landfill cost, and price of purchased galvanized scrap, using zinc-free scrap in a BOF process might be economically feasible for some ironmaking and steelmaking plants or in some particular market circumstances.

  2. Time Domain Stability Margin Assessment of the NASA Space Launch System GN&C Design for Exploration Mission One

    NASA Technical Reports Server (NTRS)

    Clements, Keith; Wall, John

    2017-01-01

    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.

  3. Time Domain Stability Margin Assessment of the NS Space Launch System GN&C Design for Exploration Mission One

    NASA Technical Reports Server (NTRS)

    Clements, Keith; Wall, John

    2017-01-01

    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.

  4. Basal area growth, carbon isotope discrimination, and intrinsic ...

    EPA Pesticide Factsheets

    Many hectares of intensively managed Douglas-fir (Pseudotsuga menziesii Mirb. Franco) stands in western North America are fertilized with nitrogen to increase growth rates. Understanding the mechanisms of response facilitates prioritization of stands for treatment. The objective of this study was to test the hypothesis that the short-term basal area growth response to a single application of 224 kg N ha-1 as urea was associated with reduced stable carbon isotope discrimination (∆13C) and increased intrinsic water use efficiency (iWUE) in a 20-yr-old plantation of Douglas-fir in the Oregon Coast Range, USA. Increment cores were measured to estimate earlywood, latewood, and total basal area increment over a time series from 1997 to 2015. Stable carbon isotope discrimination and iWUE were estimated using earlywood and latewood stable carbon isotope concentrations in tree-ring holocellulose starting seven years before fertilization in early 2009 and ending seven years after treatment. A highly significant interaction effect between fertilization treatment and year was found for total basal area growth and earlywood basal area increment. Fertilized trees showed significant total basal area growth and earlywood basal area increment in the first (2009) and second (2010) growing seasons after fertilization in 2009. A marginally significant fertilization effect was found for latewood basal area increment only in the first growing season after treatment. A significant i

  5. The association between socio-demographic marginalization and plasma glucose levels at diagnosis of gestational diabetes.

    PubMed

    Sampson, L; Dasgupta, K; Ross, N A

    2014-12-01

    We examined the association between socio-demographic marginalization and plasma glucose levels at diagnosis of gestational diabetes in a multi-ethnic and socio-economically diverse patient group. Medical charts at a Toronto gestational diabetes clinic were reviewed for women with a recorded pregnancy between 1 March 2006 and 26 April 2011. One-hour 50-g glucose challenge test values and postal code data were abstracted. Postal codes were merged with 2006 Canadian census data to compute neighbourhood-level ethnic concentration (% recent immigrants, % visible minorities) and material deprivation (% low education, % low income, single-parent households). We compared women in the highest neighbourhood quintiles for both ethnic concentration and material deprivation with all other women to explore an association between marginalization and diagnostic glucose levels. Multivariate regression models of glucose challenge test values and insulin prescription were adjusted for age, prior gestational diabetes, parity and diabetes family history. Among 531 patients with complete glucose challenge test data (mean 11.94 mmol/l, sd 1.83), those in the most marginalized neighbourhoods had 0.43 mmol/l higher glucose challenge test values (95% CI 0.08-0.78) compared with the rest of the study population. Other factors associated with higher glucose challenge test values were prior gestational diabetes (0.59 mmol/l increment, 95% CI 0.19-0.99) and diabetes family history (0.32 mmol/l increment, 95% CI -0.01 to 0.66). Each additional 1 mmol/l glucose challenge test result was associated with an increased likelihood of being prescribed insulin (odds ratio 1.33, 95% CI 1.17-1.51). Women living in the most materially deprived and ethnically concentrated neighbourhoods have higher glucose levels at diagnosis of gestational diabetes. They may need close monitoring for timely initiation of insulin. © 2014 The Authors. Diabetic Medicine © 2014 Diabetes UK.

  6. Reassessment of spiny dogfish Squalus acanthias age and growth using vertebrae and dorsal-fin spines.

    PubMed

    Bubley, W J; Kneebone, J; Sulikowski, J A; Tsang, P C W

    2012-04-01

    Male and female spiny dogfish Squalus acanthias were collected in the western North Atlantic Ocean in the Gulf of Maine between July 2006 and June 2009. Squalus acanthias ranged from 25 to 102 cm stretch total length and were caught during all months of the year except January. Age estimates derived from banding patterns visible in both the vertebrae and second dorsal-fin spines were compared. Vertebral growth increments were visualized using a modified histological staining technique, which was verified as appropriate for obtaining age estimates. Marginal increment analysis of vertebrae verified the increment periodicity, suggesting annual band deposition. Based on increased precision and accuracy of age estimates, as well as more biologically realistic parameters generated in growth models, the current study found that vertebrae provided a more reliable and accurate means of estimating age in S. acanthias than the second dorsal-fin spine. Age estimates obtained from vertebrae ranged from <1 year-old to 17 years for male and 24 years for female S. acanthias. The two-parameter von Bertalanffy growth model fit to vertebrae-derived age estimates produced parameters of L∞ = 94·23 cm and k = 0·11 for males and L∞ = 100·76 cm and k = 0·12 for females. While these growth parameters differed from those previously reported for S. acanthias in the western North Atlantic Ocean, the causes of such differences were beyond the scope of the current study and remain to be determined. © 2011 The Authors. Journal of Fish Biology © 2011 The Fisheries Society of the British Isles.

  7. Hepatic Resection for Colorectal Liver Metastases: A Cost-Effectiveness Analysis

    PubMed Central

    Beard, Stephen M.; Holmes, Michael; Price, Charles; Majeed, Ali W.

    2000-01-01

    Objective To analyze the cost-effectiveness of resection for liver metastases compared with standard nonsurgical cytotoxic treatment. Summary Background Data The efficacy of hepatic resection for metastases from colorectal cancer has been debated, despite reported 5-year survival rates of 20% to 40%. Resection is confined to specialized centers and is not widely available, perhaps because of lack of appropriate expertise, resources, or awareness of its efficacy. The cost-effectiveness of resection is important from the perspective of managed care in the United States and for the commissioning of health services in the United Kingdom. Methods A simple decision-based model was developed to evaluate the marginal costs and health benefits of hepatic resection. Estimates of resectability for liver metastases were taken from UK-reported case series data. The results of 100 hepatic resections conducted in Sheffield from 1997 to 1999 were used for the cost calculation of liver resection. Survival data from published series of resections were compiled to estimate the incremental cost per life-year gained (LYG) because of the short period of follow-up in the Sheffield series. Results Hepatic resection for colorectal liver metastases provides an estimated marginal benefit of 1.6 life-years (undiscounted) at a marginal cost of £6,742. If 17% of patients have only palliative resections, the overall cost per LYG is approximately £5,236 (£5,985 with discounted benefits). If potential benefits are extended to include 20-year survival rates, these figures fall to approximately £1,821 (£2,793 with discounted benefits). Further univariate sensitivity analysis of key model parameters showed the cost per LYG to be consistently less than £15,000. Conclusion In this model, hepatic resection appears highly cost-effective compared with nonsurgical treatments for colorectal-related liver metastases. PMID:11088071

  8. Economic analysis of alternative nutritional management of dual-purpose cow herds in central coastal Veracruz, Mexico.

    PubMed

    Absalón-Medina, Victor Antonio; Nicholson, Charles F; Blake, Robert W; Fox, Danny Gene; Juárez-Lagunes, Francisco I; Canudas-Lara, Eduardo G; Rueda-Maldonado, Bertha L

    2012-08-01

    Market information was combined with predicted input-output relationships in an economic analysis of alternative nutritional management for dual-purpose member herds of the Genesis farmer organization of central coastal Veracruz, Mexico. Cow productivity outcomes for typical management and alternative feeding scenarios were obtained from structured sets of simulations in a companion study of productivity limitations and potentials using the Cornell Net Carbohydrate and Protein System model (Version 6.0). Partial budgeting methods and sensitivity analysis were used to identify economically viable alternatives based on expected change in milk income over feed cost (change in revenues from milk sales less change in feed costs). Herd owners in coastal Veracruz have large economic incentives, from $584 to $1,131 in predicted net margin, to increase milk sales by up to 74% across a three-lactation cow lifetime by improving diets based on good quality grass and legume forages. This increment is equal to, or exceeds, in value the total yield from at least one additional lactation per cow lifetime. Furthermore, marginal rates of return (change in milk income over feed costs divided by change in variable costs when alternative practices are used) of 3.3 ± 0.8 indicate clear economic incentives to remove fundamental productivity vulnerabilities due to chronic energy deficits and impeded growth of immature cows under typical management. Sensitivity analyses indicate that the economic outcomes are robust for a variety of market conditions.

  9. Flight investigation of the effect of tail boom strakes on helicopter directional control

    NASA Technical Reports Server (NTRS)

    Kelly, Henry L.; Crowell, Cynthia A.; Yenni, Kenneth R.; Lance, Michael B.

    1993-01-01

    A joint U.S. Army/NASA flight investigation was conducted utilizing a single-rotor helicopter to determine the effectiveness of horizontally mounted tail boom strakes on directional controllability and tail rotor power during low-speed, crosswind operating conditions. Three configurations were investigated: (1) baseline (strakes off), (2) single strake (strake at upper shoulder on port side of boom), and (3) double strake (upper strake plus a lower strake on same side of boom). The strakes were employed as a means to separate airflow over the tail boom and change fuselage yawing moments in a direction to improve the yaw control margin and reduce tail rotor power. Crosswind data were obtained in 5-knot increments of airspeed from 0 to 35 knots and in 30 deg increments of wind azimuth from 0 deg to 330 deg. At the most critical wind azimuth and airspeed in terms of tail rotor power, the strakes improved the pedal margin by 6 percent of total travel and reduced tail rotor power required by 17 percent. The increase in yaw control and reduction in tail rotor power offered by the strakes can expand the helicopter operating envelope in terms of gross weight and altitude capability. The strakes did not affect the flying qualities of the vehicle at airspeeds between 35 and 100 knots.

  10. Effect of flowable composite liner and glass ionomer liner on class II gingival marginal adaptation of direct composite restorations with different bonding strategies.

    PubMed

    Aggarwal, Vivek; Singla, Mamta; Yadav, Suman; Yadav, Harish

    2014-05-01

    The purpose of the present study was to comparatively evaluate the effect of flowable composite resin liner and resin modified glass ionomer liner on gingival marginal adaptation of class II cavities restored using three bonding agents (Single Bond 3M ESPE, One Coat Self Etching Bond Coltene Whaledent; Adper Easy Bond Self-Etch Adhesive 3M ESPE) and respective composite resins, under cyclic loading. The marginal adaptation was evaluated in terms of 'continuous margin' (CM) at the gingival margin. Ninety class II cavities with margins extending 1mm below the cement-enamel junction were prepared in extracted mandibular third molars. The samples were divided into three groups: no liner placement; 0.5-1mm thick flowable resin liner placement (Filtek Z350 XT flowable resin) on gingival floor and; light cure glass ionomer (Ketac N100) liner. The groups were further subdivided into three sub-groups on the basis of the bonding agents used. Cavities were restored with composite resins (Z350 for Single Bond and Adper Easy Bond; and Synergy D6 Universal, for One Coat Self Etching Bond) in 2mm increments and the samples were mechanically loaded (60N, 1,50,000 cycles). Marginal adaptation was evaluated using a low vacuum scanning electron microscope. Statistical analysis was done with two way ANOVA with Holm-Sidak's correction for multiple comparisons. Placement of flowable composite liner significantly improved the CM values of Single Bond (78±11%) and One Coat Self Etching Bond (77±9%) compared with no liner group, but the values of CM of Adper Easy Bond were not improved (61±12%). Placement of glass ionomer liner significantly improved the values of CM in all the sub-groups (78±9%, 72±10% and 77±10% for Single Bond, One Coat Self Etching Bond & Adper Easy Bond respectively) compared with no liner group. Placement of liners improved the values of 'continuous margin' in the gingival floor of the proximal cavities restored with composite resins using different bonding agent. Placement of flowable composite liner or glass ionomer liner will improve the marginal integrity of composite restorations using etch-and-rinse and two bottle-two step self etch adhesives. To improve the marginal integrity of a single bottle adhesive, glass ionomer liner should be applied. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Influence of maxillary canine gingival margin asymmetries on the perception of smile esthetics among orthodontists and laypersons.

    PubMed

    Correa, Bruna Dieder; Vieira Bittencourt, Marcos Alan; Machado, Andre Wilson

    2014-01-01

    Our objective was to determine the perception of smile esthetics among orthodontists and laypeople with respect to asymmetries in the maxillary canines' gingival margins in full-face and close-up smile analyses. Full-face and close-up photographs of the frontal smiles of 4 subjects (2 women, 2 men) were used. The images were digitally altered to create a symmetrical image with the gingival margin levels of the maxillary canines matching the central incisors. From this new image, 5 stages of alterations were made in the gingival margin of the right canine in 0.5-mm increments. Final full-face and close-up images of the smiles were assessed by 50 orthodontists and 50 laypeople, who indicated the level of attractiveness of each smile on visual analog scales. The data collected were statistically analyzed by means of 1-way analysis of variance with the Tukey post-hoc test and the unpaired Student t test. In general, the most attractive smiles for the orthodontists were those without asymmetries and the one with a 0.5-mm asymmetry, whereas laypersons could not detect an asymmetry up to 1.5 mm (P <0.05). For both groups of raters, the lowest scores were assigned for the smiles with asymmetries of 2.0 and 2.5 mm (P <0.05). When opinions of orthodontists and laypersons were compared, in most situations a statistically significant difference was found, with orthodontists more sensitive in detecting deviations (P <0.001). Moreover, there was no significant difference (P >0.05) between the full-face and close-up assessments of the smiles. It can be concluded that the perceptions of unilateral asymmetries in the gingival margin levels of the maxillary canines were 1.0 mm for orthodontists and 1.5 to 2.0 mm for laypersons. Copyright © 2014 American Association of Orthodontists. Published by Mosby, Inc. All rights reserved.

  12. Resource Management and Contingencies in Aerospace Concurrent Engineering

    NASA Technical Reports Server (NTRS)

    Karpati, Gabe; Hyde, Tupper; Peabody, Hume; Garrison, Matthew

    2012-01-01

    significant concern in designing complex systems implementing new technologies is that while knowledge about the system is acquired incrementally, substantial financial commitments, even make-or-break decisions, must be made upfront, essentially in the unknown. One practice that helps in dealing with this dichotomy is the smart embedding of contingencies and margins in the design to serve as buffers against surprises. This issue presents itself in full force in the aerospace industry, where unprecedented systems are formulated and committed to as a matter of routine. As more and more aerospace mission concepts are generated by concurrent design laboratories, it is imperative that such laboratories apply well thought-out contingency and margin structures to their designs. The first part of this publication provides an overview of resource management techniques and standards used in the aerospace industry. That is followed by a thought provoking treatise on margin policies. The expose presents the actual flight telemetry data recorded by the thermal discipline during several recent NASA Goddard Space Flight Center missions. The margins actually achieved in flight are compared against pre-flight predictions, and the appropriateness and the ramifications of having designed with rigid margins to bounding stacked worst case conditions are assessed. The second half of the paper examines the particular issues associated with the application of contingencies and margins in the concurrent engineering environment. In closure, a discipline-by-discipline disclosure of the contingency and margin policies in use at the Integrated Design Center at NASA s Goddard Space Flight Center is made.

  13. The cost-effectiveness of targeted or universal screening for vasa praevia at 18-20 weeks of gestation in Ontario.

    PubMed

    Cipriano, L E; Barth, W H; Zaric, G S

    2010-08-01

    To estimate the cost-effectiveness of targeted and universal screening for vasa praevia at 18-20 weeks of gestation in singleton and twin pregnancies. Cost-utility analysis based on a decision-analytic model comparing relevant strategies and life-long outcomes for mother and infant(s). Ontario, Canada. A cohort of pregnant women in 1 year. We constructed a decision-analytic model to estimate the lifetime incremental costs and benefits of screening for vasa praevia. Inputs were estimated from the literature. Costs were collected from the London Health Sciences Centre, the Ontario Health Insurance Program, and other sources. We used one-way, scenario and probabilistic sensitivity analysis to determine the robustness of the results. Incremental costs, life expectancy, quality-adjusted life-years (QALY) and incremental cost-effectiveness ratio (ICER). Universal transvaginal ultrasound screening of twin pregnancies has an ICER of $5488 per QALY-gained. Screening all singleton pregnancies with the risk factors low-lying placentas, in vitro fertilisation (IVF) conception, accessory placental lobes, or velamentous cord insertion has an ICER of $15,764 per QALY-gained even though identifying some of these risk factors requires routine use of colour Doppler during transabdominal examinations. Screening women with a marginal cord insertion costs an additional $27,603 per QALY-gained. Universal transvaginal screening for vasa praevia in singleton pregnancies costs $579,164 per QALY compared with targeted screening. Compared with current practice, screening all twin pregnancies for vasa praevia with transvaginal ultrasound is cost-effective. Among the alternatives considered, the use of colour Doppler at all transabdominal ultrasound examinations of singleton pregnancies and targeted use of transvaginal ultrasound for IVF pregnancies or when the placenta has been found to be associated with one or more risk factors is cost-effective. Universal screening of singleton pregnancies is not cost-effective compared with targeted screening.

  14. Plutons: Simmer between 350° and 500°C for 10 million years, then serve cold (Invited)

    NASA Astrophysics Data System (ADS)

    Coleman, D. S.; Davis, J.

    2009-12-01

    The growing recognition that continental plutons are assembled incrementally over millions of years requires reexamination of the thermal histories of intrusive rocks. With the exception of the suggestion that pluton magma chambers can be revitalized by mafic input at their deepest structural levels, most aspects of modern pluton petrology are built on the underlying assumption that silicic plutons intrude as discrete thermal packages that undergo subsequent monotonic decay back to a steady-state geothermal gradient. The recognition that homogeneous silicic plutons are constructed over timescales too great to be single events necessitates rethinking pluton intrusion mechanisms, textures, thermochronology, chemical evolution and links to volcanic rocks. Three-dimensional thermal modeling of sheeted (horizontal and vertical) incremental pluton assembly (using HEAT3D by Wohletz, 2007) yields several results that are largely independent of intrusive geometry and may help understand bothersome field and laboratory results from plutonic rocks. 1) All increments cool quickly below hornblende closure temperature. However, late increments are emplaced into walls warmed by earlier increments, and they cycle between hornblende and biotite closure temperatures, a range in which fluid-rich melts are likely to be present. These conditions persist until the increments are far from the region of new magma flux, or the addition of increments stops. These observations are supported by Ar thermochronology and may explain why heterogeneous early marginal intrusive phases often grade into younger homogeneous interior map units. 2) Early increments become the contact metamorphic wall rocks of later increments. This observation suggests that much of the contact metamorphism associated with a given volume of plutonic rock is “lost” via textural modification of early increments during intrusion of later increments. Johnson and Glazner (CMP, in press) argue that mappable variations in pluton texture can result from textural modification during thermal cycling associated with incremental assembly. 3) The thermal structure of the model pluton evolves toward roughly spheroidal isotherms even though the pluton is assembled from thin tabular sheets. The zone of melt-bearing rock and the shape of intrapluton contact metamorphic isograds bear little resemblance to the increments from which the pluton was built. Consequently, pluton contacts mapped by variations in texture that reflect the thermal cycling inherent to incremental assembly will inevitably be “blob” or diapir-like, but will yield little insight into magma intrusion geometry. 4) Although models yield large regions of melt-bearing rock, the melt fraction is low and the melt-bearing volume at any time is small compared to the total volume of the pluton. This observation raises doubts about the connections between zoned silicic plutons and large ignimbrite eruptions.

  15. How to Assess the Value of Medicines?

    PubMed Central

    Simoens, Steven

    2010-01-01

    This study aims to discuss approaches to assessing the value of medicines. Economic evaluation assesses value by means of the incremental cost-effectiveness ratio (ICER). Health is maximized by selecting medicines with increasing ICERs until the budget is exhausted. The budget size determines the value of the threshold ICER and vice versa. Alternatively, the threshold value can be inferred from pricing/reimbursement decisions, although such values vary between countries. Threshold values derived from the value-of-life literature depend on the technique used. The World Health Organization has proposed a threshold value tied to the national GDP. As decision makers may wish to consider multiple criteria, variable threshold values and weighted ICERs have been suggested. Other approaches (i.e., replacement approach, program budgeting and marginal analysis) have focused on improving resource allocation, rather than maximizing health subject to a budget constraint. Alternatively, the generalized optimization framework and multi-criteria decision analysis make it possible to consider other criteria in addition to value. PMID:21607066

  16. How to assess the value of medicines?

    PubMed

    Simoens, Steven

    2010-01-01

    This study aims to discuss approaches to assessing the value of medicines. Economic evaluation assesses value by means of the incremental cost-effectiveness ratio (ICER). Health is maximized by selecting medicines with increasing ICERs until the budget is exhausted. The budget size determines the value of the threshold ICER and vice versa. Alternatively, the threshold value can be inferred from pricing/reimbursement decisions, although such values vary between countries. Threshold values derived from the value-of-life literature depend on the technique used. The World Health Organization has proposed a threshold value tied to the national GDP. As decision makers may wish to consider multiple criteria, variable threshold values and weighted ICERs have been suggested. Other approaches (i.e., replacement approach, program budgeting and marginal analysis) have focused on improving resource allocation, rather than maximizing health subject to a budget constraint. Alternatively, the generalized optimization framework and multi-criteria decision analysis make it possible to consider other criteria in addition to value.

  17. Cenozoic Source-to-Sink of the African margin of the Equatorial Atlantic

    NASA Astrophysics Data System (ADS)

    Rouby, Delphine; Chardon, Dominique; Huyghe, Damien; Guillocheau, François; Robin, Cecile; Loparev, Artiom; Ye, Jing; Dall'Asta, Massimo; Grimaud, Jean-Louis

    2016-04-01

    The objective of the Transform Source to Sink Project (TS2P) is to link the dynamics of the erosion of the West African Craton to the offshore sedimentary basins of the African margin of the Equatorial Atlantic at geological time scales. This margin, alternating transform and oblique segments from Guinea to Nigeria, shows a strong structural variability in the margin width, continental geology and relief, drainage networks and subsidence/accumulation patterns. We analyzed this system combining onshore geology and geomorphology as well as offshore sub-surface data. Mapping and regional correlation of dated lateritic paleo-landscape remnants allows us to reconstruct two physiographic configurations of West Africa during the Cenozoic. We corrected those reconstitutions from flexural isostasy related to the subsequent erosion. These geometries show that the present-day drainage organization stabilized by at least 29 Myrs ago (probably by 34 Myr) revealing the antiquity of the Senegambia, Niger and Volta catchments toward the Atlantic as well as of the marginal upwarp currently forming a continental divide. The drainage rearrangement that lead to this drainage organization was primarily enhanced by the topographic growth of the Hoggar swell and caused a major stratigraphic turnover along the Equatorial margin of West Africa. Elevation differences between paleo-landscape remnants give access to the spatial and temporal distribution of denudation for 3 time-increments since 45 Myrs. From this, we estimate the volumes of sediments and associated lithologies exported by the West African Craton toward different segments of the margin, taking into account the type of eroded bedrock and the successive drainage reorganizations. We compare these data to Cenozoic accumulation histories in the basins and discuss their stratigraphic expression according to the type of margin segment they are preserved in.

  18. Sealing of minimally invasive Class II fillings (slot) using an adhesive patch: sealant margin extension for prevention.

    PubMed

    Schmidlin, Patrick R; Seemann, Rainer; Filli, Tilla; Attin, Thomas; Imfeld, Thomas

    2007-01-01

    A laboratory study was performed to assess the potential of an adhesive patch to seal small, unbeveled, Class II, box-only (slot) composite fillings. After minimal access cavity preparation with an 80 pm diamond bur, 40 box-only Class II cavities were prepared mesially and distally in 20 extracted human molars using a u-shaped PCS insert (EMS). One cavity per tooth was adhesively filled with a hybrid composite material in one increment. A patch, acting as an adhesive matrice, was applied to the other cavity of each tooth to seal the restoration. The margin of the patch was located in areas easily accessible to oral hygiene measures and self-cleaning. All the teeth were subjected to thermo-mechanical stress in a computer-controlled masticator device. In 10 teeth, caries was induced in a microbial-based artificial mouth model and quantitatively determined by confocal laser scanning microscopy. Microleakage was assessed in the other 10 teeth in two planar sections after immersion in 0.5% basic fuchsin solution. The results showed no demineralization at the filling margins protected with the patch. Microleakage was observed in one sample only and was limited to the enamel. In contrast, the margins of fillings without the patch application showed a mean demineralization depth of 146 +/- 42 microm and dye penetration into the dentin in five sections. This innovative approach to sealing restorative margins with an adhesive patch results in less leakage and filling margin demineralization and merits further investigation.

  19. Comparative wood anatomy of root and stem of Citharexylum myrianthum (Verbenaceae)

    Treesearch

    Carmen Regina Marcati; Leandro Roberto Longo; Alex Wiedenhoeft; Claudia Franca Barros

    2014-01-01

    Root and stem wood anatomy of C. myrianthum (Verbenaceae) from a semideciduous seasonal forest in Botucatu municipality (22º52’20”S and 48º26’37”W), São Paulo state, Brazil, were studied. Growth increments demarcated by semi-ring porosity and marginal bands of axial parenchyma were observed in the wood of both root and stem. Many qualitative features...

  20. Cost-Utility of Competing Strategies to Prevent Endoscopic Transmission of Carbapenem-Resistant Enterobacteriaceae

    PubMed Central

    Almario, Christopher V.; May, Folasade P.; Shaheen, Nicholas J.; Murthy, Rekha; Gupta, Kapil; Jamil, Laith H.; Lo, Simon K.; Spiegel, Brennan M.R.

    2015-01-01

    OBJECTIVES Prior reports have linked patient transmission of carbapenem-resistant Enterobacteriaceae (CRE, or “superbug”) to endoscopes used during endoscopic retrograde cholangiopancreatography (ERCP). We performed a decision analysis to measure the cost-effectiveness of four competing strategies for CRE risk management. METHODS We used decision analysis to calculate the cost-effectiveness of four approaches to reduce the risk of CRE transmission among patients presenting to the hospital for symptomatic common bile duct stones. The strategies included: (1) perform ERCP followed by U.S. Food and Drug Administration (FDA)-recommended endoscope reprocessing procedures; (2) perform ERCP followed by “endoscope culture and hold”; (3) perform ERCP followed by ethylene oxide (EtO) sterilization of the endoscope; and (4) stop performing ERCP in lieu of laparoscopic cholecystectomy (LC) with common bile duct exploration (CBDE). Our outcome was incremental cost per quality-adjusted life year (QALY) gained. RESULTS In the base-case scenario, ERCP with FDA-recommended endoscope reprocessing was the most cost-effective strategy. Both the ERCP with culture and hold ($4,228,170/QALY) and ERCP with EtO sterilization ($50,572,348/QALY) strategies had unacceptable incremental costs per QALY gained. LC with CBDE was dominated, being both more costly and marginally less effective versus the alternatives. In sensitivity analysis, ERCP with culture and hold became the most cost-effective approach when the pretest probability of CRE exceeded 24%. CONCLUSIONS In institutions with a low CRE prevalence, ERCP with FDA-recommended reprocessing is the most cost-effective approach for mitigating CRE transmission risk. Only in settings with an extremely high CRE prevalence did ERCP with culture and hold become cost-effective. PMID:26526083

  1. 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

  2. Pedestrian paths: why path-dependence theory leaves health policy analysis lost in space.

    PubMed

    Brown, Lawrence D

    2010-08-01

    Path dependence, a model first advanced to explain puzzles in the diffusion of technology, has lately won allegiance among analysts of the politics of public policy, including health care policy. Though the central premise of the model--that past events and decisions shape options for innovation in the present and future--is indisputable (indeed path dependence is, so to speak, too shallow to be false), the approach, at least as applied to health policy, suffers from ambiguities that undercut its claims to illuminate policy projects such as managed care, on which this article focuses. Because path dependence adds little more than marginal value to familiar images of the politics of policy--incrementalism, for one--analysts might do well to put it on the back burner and pursue instead "thick descriptions" that help them to distinguish different degrees of openness to exogenous change among diverse policy arenas.

  3. Age and growth of the round stingray Urotrygon rogersi, a particularly fast-growing and short-lived elasmobranch.

    PubMed

    Mejía-Falla, Paola A; Cortés, Enric; Navia, Andrés F; Zapata, Fernando A

    2014-01-01

    We examined the age and growth of Urotrygon rogersi on the Colombian coast of the Eastern Tropical Pacific Ocean by directly estimating age using vertebral centra. We verified annual deposition of growth increments with marginal increment analysis. Eight growth curves were fitted to four data sets defined on the basis of the reproductive cycle (unadjusted or adjusted for age at first band) and size variables (disc width or total length). Model performance was evaluated using Akaike's Information Criterion (AIC), AIC weights and multi-model inference criteria. A two-phase growth function with adjusted age provided the best description of growth for females (based on five parameters, DW∞  =  20.1 cm, k  =  0.22 yr⁻¹) and males (based on four and five parameters, DW(∞)  =  15.5 cm, k  =  0.65 yr⁻¹). Median maturity of female and male U. rogersi is reached very fast (mean ± SE  =  1.0 ± 0.1 year). This is the first age and growth study for a species of the genus Urotrygon and results indicate that U. rogersi attains a smaller maximum size and has a shorter lifespan and lower median age at maturity than species of closely related genera. These life history traits are in contrast with those typically reported for other elasmobranchs.

  4. 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

    Purpose: A dosimetric margin (DM) is the margin in a specified direction between a structure and a specified isodose surface, corresponding to a prescription or tolerance dose. The dosimetric margin distribution (DMD) is the distribution of DMs over all directions. Given a geometric uncertainty model, representing inter- or intrafraction setup uncertainties or internal organ motion, the DMD can be used to calculate coverage Q, which is the probability that a realized target or organ-at-risk (OAR) dose metric D{sub v} exceeds the corresponding prescription or tolerance dose. Postplanning coverage evaluation quantifies the percentage of uncertainties for which target and OAR structuresmore » meet their intended dose constraints. The goal of the present work is to evaluate coverage probabilities for 28 prostate treatment plans to determine DMD sampling parameters that ensure adequate accuracy for postplanning coverage estimates. Methods: Normally distributed interfraction setup uncertainties were applied to 28 plans for localized prostate cancer, with prescribed dose of 79.2 Gy and 10 mm clinical target volume to planning target volume (CTV-to-PTV) margins. Using angular or isotropic sampling techniques, dosimetric margins were determined for the CTV, bladder and rectum, assuming shift invariance of the dose distribution. For angular sampling, DMDs were sampled at fixed angular intervals {omega} (e.g., {omega}=1 deg., 2 deg., 5 deg., 10 deg., 20 deg.). Isotropic samples were uniformly distributed on the unit sphere resulting in variable angular increments, but were calculated for the same number of sampling directions as angular DMDs, and accordingly characterized by the effective angular increment {omega}{sub eff}. In each direction, the DM was calculated by moving the structure in radial steps of size {delta}(=0.1,0.2,0.5,1 mm) until the specified isodose was crossed. Coverage estimation accuracy {Delta}Q was quantified as a function of the sampling parameters {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

  5. 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

    A dosimetric margin (DM) is the margin in a specified direction between a structure and a specified isodose surface, corresponding to a prescription or tolerance dose. The dosimetric margin distribution (DMD) is the distribution of DMs over all directions. Given a geometric uncertainty model, representing inter- or intrafraction setup uncertainties or internal organ motion, the DMD can be used to calculate coverage Q, which is the probability that a realized target or organ-at-risk (OAR) dose metric D, exceeds the corresponding prescription or tolerance dose. Postplanning coverage evaluation quantifies the percentage of uncertainties for which target and OAR structures meet their intended dose constraints. The goal of the present work is to evaluate coverage probabilities for 28 prostate treatment plans to determine DMD sampling parameters that ensure adequate accuracy for postplanning coverage estimates. Normally distributed interfraction setup uncertainties were applied to 28 plans for localized prostate cancer, with prescribed dose of 79.2 Gy and 10 mm clinical target volume to planning target volume (CTV-to-PTV) margins. Using angular or isotropic sampling techniques, dosimetric margins were determined for the CTV, bladder and rectum, assuming shift invariance of the dose distribution. For angular sampling, DMDs were sampled at fixed angular intervals w (e.g., w = 1 degree, 2 degrees, 5 degrees, 10 degrees, 20 degrees). Isotropic samples were uniformly distributed on the unit sphere resulting in variable angular increments, but were calculated for the same number of sampling directions as angular DMDs, and accordingly characterized by the effective angular increment omega eff. In each direction, the DM was calculated by moving the structure in radial steps of size delta (=0.1, 0.2, 0.5, 1 mm) until the specified isodose was crossed. Coverage estimation accuracy deltaQ was quantified as a function of the sampling parameters omega or omega eff and delta. The 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.

  6. Implementing Kernel Methods Incrementally by Incremental Nonlinear Projection Trick.

    PubMed

    Kwak, Nojun

    2016-05-20

    Recently, the nonlinear projection trick (NPT) was introduced enabling direct computation of coordinates of samples in a reproducing kernel Hilbert space. With NPT, any machine learning algorithm can be extended to a kernel version without relying on the so called kernel trick. However, NPT is inherently difficult to be implemented incrementally because an ever increasing kernel matrix should be treated as additional training samples are introduced. In this paper, an incremental version of the NPT (INPT) is proposed based on the observation that the centerization step in NPT is unnecessary. Because the proposed INPT does not change the coordinates of the old data, the coordinates obtained by INPT can directly be used in any incremental methods to implement a kernel version of the incremental methods. The effectiveness of the INPT is shown by applying it to implement incremental versions of kernel methods such as, kernel singular value decomposition, kernel principal component analysis, and kernel discriminant analysis which are utilized for problems of kernel matrix reconstruction, letter classification, and face image retrieval, respectively.

  7. Cost-effectiveness analysis of malaria rapid diagnostic tests for appropriate treatment of malaria at the community level in Uganda.

    PubMed

    Hansen, Kristian S; Ndyomugyenyi, Richard; Magnussen, Pascal; Lal, Sham; Clarke, Siân E

    2017-06-01

    In Sub-Saharan Africa, malaria remains a major cause of morbidity and mortality among children under 5, due to lack of access to prompt and appropriate diagnosis and treatment. Many countries have scaled-up community health workers (CHWs) as a strategy towards improving access. The present study was a cost-effectiveness analysis of the introduction of malaria rapid diagnostic tests (mRDTs) performed by CHWs in two areas of moderate-to-high and low malaria transmission in rural Uganda. CHWs were trained to perform mRDTs and treat children with artemisinin-based combination therapy (ACT) in the intervention arm while CHWs offered treatment based on presumptive diagnosis in the control arm. Data on the proportion of children with fever 'appropriately treated for malaria with ACT' were captured from a randomised trial. Health sector costs included: training of CHWs, community sensitisation, supervision, allowances for CHWs and provision of mRDTs and ACTs. The opportunity costs of time utilised by CHWs were estimated based on self-reporting. Household costs of subsequent treatment-seeking at public health centres and private health providers were captured in a sample of households. mRDTs performed by CHWs was associated with large improvements in appropriate treatment of malaria in both transmission settings. This resulted in low incremental costs for the health sector at US$3.0 per appropriately treated child in the moderate-to-high transmission area. Higher incremental costs at US$13.3 were found in the low transmission area due to lower utilisation of CHW services and higher programme costs. Incremental costs from a societal perspective were marginally higher. The use of mRDTs by CHWs improved the targeting of ACTs to children with malaria and was likely to be considered a cost-effective intervention compared to a presumptive diagnosis in the moderate-to-high transmission area. In contrast to this, in the low transmission area with low attendance, RDT use by CHWs was not a low cost intervention. © The Author 2017. Published by Oxford University Press in association with The London School of Hygiene and Tropical Medicine.

  8. Cost-effectiveness analysis of malaria rapid diagnostic tests for appropriate treatment of malaria at the community level in Uganda

    PubMed Central

    Ndyomugyenyi, Richard; Magnussen, Pascal; Lal, Sham; Clarke, Siân E

    2017-01-01

    Abstract In Sub-Saharan Africa, malaria remains a major cause of morbidity and mortality among children under 5, due to lack of access to prompt and appropriate diagnosis and treatment. Many countries have scaled-up community health workers (CHWs) as a strategy towards improving access. The present study was a cost-effectiveness analysis of the introduction of malaria rapid diagnostic tests (mRDTs) performed by CHWs in two areas of moderate-to-high and low malaria transmission in rural Uganda. CHWs were trained to perform mRDTs and treat children with artemisinin-based combination therapy (ACT) in the intervention arm while CHWs offered treatment based on presumptive diagnosis in the control arm. Data on the proportion of children with fever ‘appropriately treated for malaria with ACT’ were captured from a randomised trial. Health sector costs included: training of CHWs, community sensitisation, supervision, allowances for CHWs and provision of mRDTs and ACTs. The opportunity costs of time utilised by CHWs were estimated based on self-reporting. Household costs of subsequent treatment-seeking at public health centres and private health providers were captured in a sample of households. mRDTs performed by CHWs was associated with large improvements in appropriate treatment of malaria in both transmission settings. This resulted in low incremental costs for the health sector at US$3.0 per appropriately treated child in the moderate-to-high transmission area. Higher incremental costs at US$13.3 were found in the low transmission area due to lower utilisation of CHW services and higher programme costs. Incremental costs from a societal perspective were marginally higher. The use of mRDTs by CHWs improved the targeting of ACTs to children with malaria and was likely to be considered a cost-effective intervention compared to a presumptive diagnosis in the moderate-to-high transmission area. In contrast to this, in the low transmission area with low attendance, RDT use by CHWs was not a low cost intervention. PMID:28453718

  9. Minimal Residual Disease Evaluation in Childhood Acute Lymphoblastic Leukemia: An Economic Analysis

    PubMed Central

    Gajic-Veljanoski, O.; Pham, B.; Pechlivanoglou, P.; Krahn, M.; Higgins, Caroline; Bielecki, Joanna

    2016-01-01

    Background Minimal residual disease (MRD) testing by higher performance techniques such as flow cytometry and polymerase chain reaction (PCR) can be used to detect the proportion of remaining leukemic cells in bone marrow or peripheral blood during and after the first phases of chemotherapy in children with acute lymphoblastic leukemia (ALL). The results of MRD testing are used to reclassify these patients and guide changes in treatment according to their future risk of relapse. We conducted a systematic review of the economic literature, cost-effectiveness analysis, and budget-impact analysis to ascertain the cost-effectiveness and economic impact of MRD testing by flow cytometry for management of childhood precursor B-cell ALL in Ontario. Methods A systematic literature search (1998–2014) identified studies that examined the incremental cost-effectiveness of MRD testing by either flow cytometry or PCR. We developed a lifetime state-transition (Markov) microsimulation model to quantify the cost-effectiveness of MRD testing followed by risk-directed therapy to no MRD testing and to estimate its marginal effect on health outcomes and on costs. Model input parameters were based on the literature, expert opinion, and data from the Pediatric Oncology Group of Ontario Networked Information System. Using predictions from our Markov model, we estimated the 1-year cost burden of MRD testing versus no testing and forecasted its economic impact over 3 and 5 years. Results In a base-case cost-effectiveness analysis, compared with no testing, MRD testing by flow cytometry at the end of induction and consolidation was associated with an increased discounted survival of 0.0958 quality-adjusted life-years (QALYs) and increased discounted costs of $4,180, yielding an incremental cost-effectiveness ratio (ICER) of $43,613/QALY gained. After accounting for parameter uncertainty, incremental cost-effectiveness of MRD testing was associated with an ICER of $50,249/QALY gained. In the budget-impact analysis, the 1-year cost expenditure for MRD testing by flow cytometry in newly diagnosed patients with precursor B-cell ALL was estimated at $340,760. We forecasted that the province would have to pay approximately $1.3 million over 3 years and $2.4 million over 5 years for MRD testing by flow cytometry in this population. Conclusions Compared with no testing, MRD testing by flow cytometry in newly diagnosed patients with precursor B-cell ALL represents good value for money at commonly used willingness-to-pay thresholds of $50,000/QALY and $100,000/QALY. PMID:27099644

  10. Minimal Residual Disease Evaluation in Childhood Acute Lymphoblastic Leukemia: An Economic Analysis.

    PubMed

    2016-01-01

    Minimal residual disease (MRD) testing by higher performance techniques such as flow cytometry and polymerase chain reaction (PCR) can be used to detect the proportion of remaining leukemic cells in bone marrow or peripheral blood during and after the first phases of chemotherapy in children with acute lymphoblastic leukemia (ALL). The results of MRD testing are used to reclassify these patients and guide changes in treatment according to their future risk of relapse. We conducted a systematic review of the economic literature, cost-effectiveness analysis, and budget-impact analysis to ascertain the cost-effectiveness and economic impact of MRD testing by flow cytometry for management of childhood precursor B-cell ALL in Ontario. A systematic literature search (1998-2014) identified studies that examined the incremental cost-effectiveness of MRD testing by either flow cytometry or PCR. We developed a lifetime state-transition (Markov) microsimulation model to quantify the cost-effectiveness of MRD testing followed by risk-directed therapy to no MRD testing and to estimate its marginal effect on health outcomes and on costs. Model input parameters were based on the literature, expert opinion, and data from the Pediatric Oncology Group of Ontario Networked Information System. Using predictions from our Markov model, we estimated the 1-year cost burden of MRD testing versus no testing and forecasted its economic impact over 3 and 5 years. In a base-case cost-effectiveness analysis, compared with no testing, MRD testing by flow cytometry at the end of induction and consolidation was associated with an increased discounted survival of 0.0958 quality-adjusted life-years (QALYs) and increased discounted costs of $4,180, yielding an incremental cost-effectiveness ratio (ICER) of $43,613/QALY gained. After accounting for parameter uncertainty, incremental cost-effectiveness of MRD testing was associated with an ICER of $50,249/QALY gained. In the budget-impact analysis, the 1-year cost expenditure for MRD testing by flow cytometry in newly diagnosed patients with precursor B-cell ALL was estimated at $340,760. We forecasted that the province would have to pay approximately $1.3 million over 3 years and $2.4 million over 5 years for MRD testing by flow cytometry in this population. Compared with no testing, MRD testing by flow cytometry in newly diagnosed patients with precursor B-cell ALL represents good value for money at commonly used willingness-to-pay thresholds of $50,000/QALY and $100,000/QALY.

  11. Procedural Portfolio Planning in Plastic Surgery, Part 1: Strategic Changes in Clinical Practice to Increase Physician Revenue, Improve Operative Throughput, and Maintain Patient Satisfaction.

    PubMed

    Hultman, Charles Scott

    2016-06-01

    Portfolio planning in health care represents the strategic prioritization of services that permits an organization to better achieve its goals of margin and mission. Because of recent volatility in the economy, declining reimbursement, and rising costs of providing care, such strategic planning has become increasingly important if physicians want to remain leaders in health care. This project assesses the financial impact of procedural portfolio planning on an academic plastic surgery practice from the physician's perspective. We tracked the top 50 procedures, defined as total charges per CPT code, that were performed in our baseline year, for 6 providers in a stable plastic surgery practice. At the end of the first year, we implemented 3 types of strategic changes: growth of areas with high contribution margin (laser resurfacing of burn scars), curtailment of high-risk procedures with negative contribution margin (panniculectomy in smokers), and improved efficiency of mission-critical services with high resource consumption (free-flap breast reconstruction). During the 2-year study period, we had no turnover in faculty, did not pursue any formal marketing, did not change our surgical fees or billing system, provided care independent of payer mix, and maintained our commitment to indigent care. Outcome measures included procedural charges and revenue, collection rates, work relative value units, operating room times, idle times (room time less case time), receipts/minute in operating room, uncompensated charity care, and patient satisfaction (Press-Gainey scores). Before the study period, annual incremental growth in our practice was 1% to 2%, in terms of charges and receipts. After implementation of the portfolio planning project, the financial position of our division improved significantly, with patient satisfaction rates increasing from 85.5% to 94.1% and charity care remaining constant at US $400,000 per year. Encounters, work relative value units, charges, and receipts all increased by 16% to 27%, with receipts/minute increasing from US $5.60 per minute to US $7.28 per minute. Interestingly, but not surprisingly, highest margin cases did not correspond with highest volume or highest revenue cases; portfolio analysis helped us to align these parameters, without sacrificing patient satisfaction or commitment to indigent care. The highest receipt/minute procedure was laser ablation of vascular lesions (US $23.87), whereas one of the lowest receipt/minute cases was muscle free flap (US $3.07). Procedural portfolio analysis is a powerful tool that can guide strategy and positively impact the financial position and clinical value of the services provided by an academic plastic surgery practice. Identifying high margin procedures allows the surgeon to focus marketing efforts, target areas of future growth, and optimize the blend of margin and mission.

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

    Kristine Barrett; Shannon Bragg-Sitton

    The Advanced Light Water Reactor (LWR) Nuclear Fuel Development Research and Development (R&D) Pathway encompasses strategic research focused on improving reactor core economics and safety margins through the development of an advanced fuel cladding system. To achieve significant operating improvements while remaining within safety boundaries, significant steps beyond incremental improvements in the current generation of nuclear fuel are required. Fundamental improvements are required in the areas of nuclear fuel composition, cladding integrity, and the fuel/cladding interaction to allow power uprates and increased fuel burn-up allowance while potentially improving safety margin through the adoption of an “accident tolerant” fuel system thatmore » would offer improved coping time under accident scenarios. With a development time of about 20 – 25 years, advanced fuel designs must be started today and proven in current reactors if future reactor designs are to be able to use them with confidence.« less

  13. Evaluation of the incremental cost to the National Health Service of prescribing analogue insulin

    PubMed Central

    Holden, Sarah E; Poole, Chris D; Morgan, Christopher Ll

    2011-01-01

    Introduction Insulin analogues have become increasingly popular despite their greater cost compared with human insulin. The aim of this study was to calculate the incremental cost to the National Health Service (NHS) of prescribing analogue insulin preparations instead of their human insulin alternatives. Methods Open-source data from the four UK prescription pricing agencies from 2000 to 2009 were analysed. Cost was adjusted for inflation and reported in UK pounds at 2010 prices. Results Over the 10-year period, the NHS spent a total of £2732 million on insulin. The total annual cost increased from £156 million to £359 million, an increase of 130%. The annual cost of analogue insulin increased from £18.2 million (12% of total insulin cost) to £305 million (85% of total insulin cost), whereas the cost of human insulin decreased from £131 million (84% of total insulin cost) to £51 million (14% of total insulin cost). If it is assumed that all patients using insulin analogues could have received human insulin instead, the overall incremental cost of analogue insulin was £625 million. Conclusion Given the high marginal cost of analogue insulin, adherence to prescribing guidelines recommending the preferential use of human insulin would have resulted in considerable financial savings over the period. PMID:22021891

  14. Steeply-dipping extension fractures in the Newark basin, New Jersey

    USGS Publications Warehouse

    Herman, G.C.

    2009-01-01

    Late Triassic and Early Jurassic bedrock in the Newark basin is pervasively fractured as a result of Mesozoic rifting of the east-central North American continental margin. Tectonic rifting imparted systematic sets of steeply-dipping, en ??chelon, Mode I, extension fractures in basin strata including ordinary joints and veins. These fractures are arranged in transitional-tensional arrays resembling normal dip-slip shear zones. They contributed to crustal stretching, sagging, and eventual faulting of basin rift deposits. Extension fractures display progressive linkage and spatial clustering that probably controlled incipient fault growth. They cluster into three prominent strike groups correlated to early, intermediate, and late-stage tectonic events reflecting about 50- 60?? of counterclockwise rotation of incremental stretching directions. Finite strain analyses show that extension fractures allowed the stretching of basin strata by a few percent, and these fractures impart stratigraphic dips up to a few degrees in directions opposing fracture dips. Fracture groups display three-dimensional spatial variability but consistent geometric relations. Younger fractures locally cut across and terminate against older fractures having more complex vein-cement morphologies and bed-normal folds from stratigraphic compaction. A fourth, youngest group of extension fractures occur sporadically and strike about E-W in obliquely inverted crustal blocks. A geometric analysis of overlapping fracture sets shows how fracture groups result from incremental rotation of an extending tectonic plate, and that old fractures can reactivate with oblique slip components in the contemporary, compressive stress regime. ?? 2008 Elsevier Ltd. All rights reserved.

  15. Westward-directed Grenvillian thrusting on the western margin of Fennoscandia: evidence from syn-kinematic pegmatites.

    NASA Astrophysics Data System (ADS)

    Henderson, I.

    2004-12-01

    Magmatism is often described as being syn-kinematic where one or more increments of intrusion punctuate deformation with successive generations of injections being progressively deformed. Recent studies have also demonstrated that there is a strong link between sites of concentrated magmatism and crustal deformation zones. Pegmatite formation in the Mesoproterozoic of south Norway has always been considered as post-kinematic in nature relative to Sveconorwegian (Grenvillian) deformation (1.13Ga to ~0.85Ga) during accretion of the SW margin of Baltica. We present structural data demonstrating that the pegmatites are kinematically related to fold geometries associated with peak metamorphism and form an integral part of the deformation episode associated with terrane accretion. Undeformed pegmatites are emplaced in sub-horizontal fractures suggesting that the maximum compressive stress was sub-horizontal. The pegmatites display a systematic deformation pattern that is consistent with deformation in the limbs of the isoclinal folds in the country rock into which they intrude. The sense of shear of deformation kinematics on the pegmatites reverse across the isoclinal fold limbs suggesting that the pegmatites are syn-deformational and that they have been injected into fractures intrinsically linked to the fold development. Pegmatites are also deformed into asymmetric anticlinal folds above thrust structures and are cut by thrust structures. We also present data which demonstrates that the style of deformation changes with proximity to the major terrane-bounding thrust structure and that the pegmatites demonstrate classic imbricate style geometries on a regional scale related to regional transpression. This evidence suggests that the pegmatites are syn-deformational and were injected into thrust-related fractures and that the pegmatites are structurally related to Sveconorwegian fold geometries associated with peak metamorphism at approximately 1.14Ga. Deformation was progressive and incremental with longer periods of ductile deformation at low strain rate punctuated by shorter periods of fracturing and pegmatite injection at high strain rate. The pegmatites also, therefore, delineate the orogenic event responsible for overthrusting of the Bamble Terrane with the underlying Telemark Terrane during crustal accretion on the western margin of Fennoscandia. We also present preliminary Re-Os data from some of these pegmatites to date the exact timing of thrusting. This work therefore implies an intimate spatial and temporal relationship between deformation and magmatism during crustal accretion on the western margin of Fennoscandia.

  16. Higher mortgages, lower energy bills: The real economics of buying an energy-efficient home

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

    Mills, E.

    1987-02-01

    To measure the actual costs and benefits of buying an energy- efficient home, it is necessary to employ a cash-flow model that accounts for mortgage interest and other charges associated with the incremental costs of conservation measures. The ability to make payments gradually over the term of a mortgage, energy savings, and tax benefits contribute to increased cost effectiveness. Conversely, financial benefits are reduced by interest payments, insurance, taxes, and various fees linked to the (higher) sale price of an energy-efficient home. Accounting for these factors can yield a strikingly different picture from those given by commonly used ''engineering'' indicators,more » such as simple payback time, internal rate of return, or net present value (NPV), which are based solely on incremental costs and energy savings. This analysis uses actual energy savings data and incremental construction costs to evaluate the mortgage cash flow for 79 of the 144 energy-efficient homes constructed in Minnesota under the Energy-Efficient Housing Demonstration Program (EEHDP) initiated in 1980 by the Minnesota Housing Finance Agency. Using typical lending terms and fees, we find that the mean mortgage-NPV derived from the homeowners' real cash flow (including construction and financing costs) is 20% lower than the standard engineering-NPV of the conservation investment: $7981 versus $9810. For eight homes, the mortgage-NPV becomes negative once we account for the various mortgage-related effects. Sensitivities to interest rates, down payment, loan term, and marginal tax rate are included to illustrate the often large impact of alternative assumptions about these parameters. The most dramatic effect occurs when the loan term is reduced from 30 to 15 years and the mortgage NPV falls to -$925. We also evaluate the favorable Federal Home Administration (FHA) terms actually applied to the EEHDP homes. 8 refs., 4 figs., 3 tabs.« less

  17. Environmental and ammonoid faunal changes related to Albian Bay of Biscay opening: Insights from the northern margin of the Basque-Cantabrian Basin

    NASA Astrophysics Data System (ADS)

    Agirrezabala, Luis M.; López-Horgue, Mikel A.

    2017-12-01

    The opening and ocean floor spreading of the Bay of Biscay began in the earliest Albian. The integrative study of the Albian sedimentary record and its ammonoid fauna (around 250 specimens) from the northern margin of the Basque-Cantabrian Basin indicates that environmental changes, occurred as a consequence of the Bay of Biscay opening, triggered significant ammonoid bioevents. Main bioevents are diversity changes in the ammonoid associations, occurrence of large forms (diameter up to 0.45 m) and the incursion of elements from other basins. Time-correlation of faulting pulses with ammonoid bioevents indicates that transtensive tectonics was ultimately the major control on the marine environmental conditions such as depth, sea bottom physiography, seaways, sedimentary systems and sea-water chemistry. The pulsating faulting during the Albian led to the increment of the subsidence rate, the deepening and widening of the margin and the progressive increase in the oceanic circulation between the margin and the nascent Bay of Biscay and North Atlantic. In addition, Albian synsedimentary faults constituted conduits for ascending magmas and hydrocarbon-rich hydrothermal fluids, which expelled to the seafloor, causing changes in the sediments, the sea-water chemistry (fertilization) and biota. The integration of sedimentological and palaeontological data has given the basis for a conceptual model of the ammonoid habitats.

  18. Petrology and age of volcanic-arc rocks from the continental margin of the Bering Sea: implications for Early Eocene relocation of plate boundaries

    USGS Publications Warehouse

    Davis, A.S.; Pickthorn, L.-B.G.; Vallier, T.L.; Marlow, M. S.

    1989-01-01

    Eocene volcanic flow and dike rocks from the Beringian margin have arc characteristics, implying a convergent history for this region during the early Tertiary. Chemical and mineralogical compositions are similar to those of modern Aleutian-arc lavas. They also resemble volcanic-arc compositions from western mainland Alaska, although greater chemical diversity and a stronger continental influence are observed in the Alaskan mainland rocks. Early Eocene ages of 54.4-50.2 Ma for the Beringian samples are well constrained by conventional K-Ar ages of nine plagioclase separates and by concordant 40Ar/39Ar incremental heating and total-fusion experiments. A concordant U-Pb zircon age of 53 Ma for the quartz-diorite dike is in good agreement with the K-Ar data. Plate motion studies of the North Pacific Ocean indicate more northerly directed subduction prior to the Tertiary and a continuous belt of arc-type volcanism extending from Siberia, along the Beringian margin, into mainland Alaska. Around 56 Ma (chron 25-24), subduction changed to a more westerly direction and subduction-related volcanism ceased for most of mainland Alaska. The increasingly oblique angle of convergence should have ended subduction along the Beringian margin as well. However, consistent ages of 54-50 Ma indicate a final pulse in arc-type magmatism during this period of plate adjustment. -from Authors

  19. Three-Phase AC Optimal Power Flow Based Distribution Locational Marginal Price: Preprint

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

    Yang, Rui; Zhang, Yingchen

    2017-05-17

    Designing market mechanisms for electricity distribution systems has been a hot topic due to the increased presence of smart loads and distributed energy resources (DERs) in distribution systems. The distribution locational marginal pricing (DLMP) methodology is one of the real-time pricing methods to enable such market mechanisms and provide economic incentives to active market participants. Determining the DLMP is challenging due to high power losses, the voltage volatility, and the phase imbalance in distribution systems. Existing DC Optimal Power Flow (OPF) approaches are unable to model power losses and the reactive power, while single-phase AC OPF methods cannot capture themore » phase imbalance. To address these challenges, in this paper, a three-phase AC OPF based approach is developed to define and calculate DLMP accurately. The DLMP is modeled as the marginal cost to serve an incremental unit of demand at a specific phase at a certain bus, and is calculated using the Lagrange multipliers in the three-phase AC OPF formulation. Extensive case studies have been conducted to understand the impact of system losses and the phase imbalance on DLMPs as well as the potential benefits of flexible resources.« less

  20. The SIMS trial: adjustable anchored single-incision mini-slings versus standard tension-free midurethral slings in the surgical management of female stress urinary incontinence. A study protocol for a pragmatic, multicentre, non-inferiority randomised controlled trial

    PubMed Central

    Abdel-Fattah, Mohamed; MacLennan, Graeme; Kilonzo, Mary; Assassa, R Phil; McCormick, Kirsty; Davidson, Tracey; McDonald, Alison; N’Dow, James; Wardle, Judith; Norrie, John

    2017-01-01

    Introduction Single-incision mini-slings (SIMS) represent the third generation of midurethral slings. They have been developed with the aim of offering a true ambulatory procedure for treatment of female stress urinary incontinence (SUI) with reduced morbidity and earlier recovery while maintaining similar efficacy to standard midurethral slings (SMUS). The aim of this study is to determine the clinical and cost-effectiveness of adjustable anchored SIMS compared with tension-free SMUS in the surgical management of female SUI, with 3-year follow-up. Methods and analysis A pragmatic, multicentre, non-inferiority randomised controlled trial. Primary outcome measure The primary outcome measure is the patient-reported success rate measured by the Patient Global Impression of Improvement at 12 months. The primary economic outcome will be incremental cost per quality-adjusted life year gained at 12 months. Secondary outcome measures The secondary outcomes measures include adverse events, objective success rates, impact on other lower urinary tract symptoms, health-related quality of life profile and sexual function, and reoperation rates for SUI. Secondary economic outcomes include National Health Service and patient primary and secondary care resource use and costs, incremental cost-effectiveness and incremental net benefit. Statistical analysis The statistical analysis of the primary outcome will be by intention-to-treat and also a per-protocol analysis. Results will be displayed as estimates and 95% CIs. CIs around observed differences will then be compared with the prespecified non-inferiority margin. Secondary outcomes will be analysed similarly. Ethics and dissemination The North of Scotland Research Ethics Committee has approved this study (13/NS/0143). The dissemination plans include HTA monograph, presentation at international scientific meetings and publications in high-impact, open-access journals. The results will be included in the updates of the National Institute for Health and Care Excellence and the European Association of Urology guidelines; these two specific guidelines directly influence practice in the UK and worldwide specialists, respectively. In addition, plain English-language summary of the main findings/results will be presented for relevant patient organisations. Trial registration number ISRCTN93264234. The SIMS study is currently recruiting in 20 UK research centres. The first patient was randomised on 4 February 2014, with follow-up to be completed at the end of February 2020. PMID:28801396

  1. Incremental soil sampling root water uptake, or be great through others

    USDA-ARS?s Scientific Manuscript database

    Ray Allmaras pursued several research topics in relation to residue and tillage research. He looked for new tools to help explain soil responses to tillage, including disk permeameters and image analysis. The incremental sampler developed by Pikul and Allmaras allowed small-depth increment, volumetr...

  2. Sugar-sweetened beverage consumption and genetic predisposition to obesity in 2 Swedish cohorts.

    PubMed

    Brunkwall, Louise; Chen, Yan; Hindy, George; Rukh, Gull; Ericson, Ulrika; Barroso, Inês; Johansson, Ingegerd; Franks, Paul W; Orho-Melander, Marju; Renström, Frida

    2016-09-01

    The consumption of sugar-sweetened beverages (SSBs), which has increased substantially during the last decades, has been associated with obesity and weight gain. Common genetic susceptibility to obesity has been shown to modify the association between SSB intake and obesity risk in 3 prospective cohorts from the United States. We aimed to replicate these findings in 2 large Swedish cohorts. Data were available for 21,824 healthy participants from the Malmö Diet and Cancer study and 4902 healthy participants from the Gene-Lifestyle Interactions and Complex Traits Involved in Elevated Disease Risk Study. Self-reported SSB intake was categorized into 4 levels (seldom, low, medium, and high). Unweighted and weighted genetic risk scores (GRSs) were constructed based on 30 body mass index [(BMI) in kg/m(2)]-associated loci, and effect modification was assessed in linear regression equations by modeling the product and marginal effects of the GRS and SSB intake adjusted for age-, sex-, and cohort-specific covariates, with BMI as the outcome. In a secondary analysis, models were additionally adjusted for putative confounders (total energy intake, alcohol consumption, smoking status, and physical activity). In an inverse variance-weighted fixed-effects meta-analysis, each SSB intake category increment was associated with a 0.18 higher BMI (SE = 0.02; P = 1.7 × 10(-20); n = 26,726). In the fully adjusted model, a nominal significant interaction between SSB intake category and the unweighted GRS was observed (P-interaction = 0.03). Comparing the participants within the top and bottom quartiles of the GRS to each increment in SSB intake was associated with 0.24 (SE = 0.04; P = 2.9 × 10(-8); n = 6766) and 0.15 (SE = 0.04; P = 1.3 × 10(-4); n = 6835) higher BMIs, respectively. The interaction observed in the Swedish cohorts is similar in magnitude to the previous analysis in US cohorts and indicates that the relation of SSB intake and BMI is stronger in people genetically predisposed to obesity.

  3. Development of the Nonstationary Incremental Analysis Update Algorithm for Sequential Data Assimilation System

    NASA Astrophysics Data System (ADS)

    Ham, Yoo-Geun; Song, Hyo-Jong; Jung, Jaehee; Lim, Gyu-Ho

    2017-04-01

    This study introduces a altered version of the incremental analysis updates (IAU), called the nonstationary IAU (NIAU) method, to enhance the assimilation accuracy of the IAU while retaining the continuity of the analysis. Analogous to the IAU, the NIAU is designed to add analysis increments at every model time step to improve the continuity in the intermittent data assimilation. Still, unlike the IAU, the NIAU method applies time-evolved forcing employing the forward operator as rectifications to the model. The solution of the NIAU is better than that of the IAU, of which analysis is performed at the start of the time window for adding the IAU forcing, in terms of the accuracy of the analysis field. It is because, in the linear systems, the NIAU solution equals that in an intermittent data assimilation method at the end of the assimilation interval. To have the filtering property in the NIAU, a forward operator to propagate the increment is reconstructed with only dominant singular vectors. An illustration of those advantages of the NIAU is given using the simple 40-variable Lorenz model.

  4. 75 FR 13610 - Office of New Reactors; Interim Staff Guidance on Implementation of a Seismic Margin Analysis for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-22

    ... Staff Guidance on Implementation of a Seismic Margin Analysis for New Reactors Based on Probabilistic... Seismic Margin Analysis for New Reactors Based on Probabilistic Risk Assessment,'' (Agencywide Documents.../COL-ISG-020 ``Implementation of a Seismic Margin Analysis for New Reactors Based on Probabilistic Risk...

  5. Growth hormone regimens in Australia: analysis of the first 3 years of treatment for idiopathic growth hormone deficiency and idiopathic short stature.

    PubMed

    Hughes, Ian P; Harris, Mark; Choong, Catherine S; Ambler, Geoff; Cutfield, Wayne; Hofman, Paul; Cowell, Chris T; Werther, George; Cotterill, Andrew; Davies, Peter S W

    2012-07-01

    To investigate response to growth hormone (GH) in the first, second and third years of treatment for all idiopathic GH-deficient (GHD) and idiopathic short stature (ISS) patients in Australia. Eligibility for subsidized GH treatment in Australia is determined on auxological criteria for the indication of Short Stature and Slow Growth (SSSG), which includes ISS (SSSG-ISS). The biochemical GHD (BGHD, peak GH < 10 mU/l) and SSSG indications are treated similarly: starting dose of 4·5 mg/m(2)/week with provision for incremental dosing. Some ISS patients were specifically diagnosed with familial short stature (SSSG-FSS). Responses for each year of treatment for BGHD, SSSG-ISS and SSSG-FSS cohorts were compared in relation to influencing variables and with international benchmarks. The effect of incremental dosing was assessed. Australian BGHD, SSSG-ISS and SSSG-FSS patients who had completed 1, 2, or 3 years of treatment and were currently receiving GH. Growth hormone dose, change in height-standard deviation score (ΔSDS) and growth velocity (GV). First-year response was 2-3 times greater than that in subsequent years: ΔSDS(1st year) = 0·92, 0·50 and 0·46 for BGHD, SSSG-ISS and SSSG-FSS, respectively. Responses were similar to international reports and inversely related to age at commencement of GH. First-year GV-for-age for BGHD patients was similar to international standards for idiopathic GHD. However, girls had an inferior response to boys when treatment commenced at <6 years of age. First-year GV-for-age for SSSG-ISS/FSS patients was less than ISS standards. Dose increments attenuated the first- to second-year decline in response to BGHD but marginally improved the responses for SSSG-ISS/FSS. The Australian auxology-based GH programme produces comparable responses to international programmes. A lower starting dose is offset by the initiation of treatment at younger ages. Incremental dosing does not appear optimal. A first-year dose of 6·4-6·9 mg/m(2)/week for GHD and 8·9 mg/m(2)/week for ISS with early commencement of GH treatment may be most efficacious. © 2012 Blackwell Publishing Ltd.

  6. Aerobic exercise for vasomotor menopausal symptoms: A cost-utility analysis based on the Active Women trial.

    PubMed

    Goranitis, Ilias; Bellanca, Leana; Daley, Amanda J; Thomas, Adele; Stokes-Lampard, Helen; Roalfe, Andrea K; Jowett, Sue

    2017-01-01

    To compare the cost-utility of two exercise interventions relative to a control group for vasomotor menopausal symptoms. Economic evaluation taking a UK National Health Service and Personal Social Services perspective and a societal perspective. Primary care. Peri- and postmenopausal women who have not used hormone therapy in the past 3 months and experience ≥ 5 episodes of vasomotor symptoms daily. An individual and a social support-based exercise intervention were evaluated. The former (Exercise-DVD), aimed to prompt exercise with purpose-designed DVD and written materials, whereas the latter (Exercise-Social support) with community exercise social support groups. Costs and outcomes associated with these interventions were compared to those of a control group, who could only have an exercise consultation. An incremental cost-utility analysis was undertaken using bootstrapping to account for the uncertainty around cost-effectiveness point-estimates. Cost per quality-adjusted life-year (QALY). Data for 261 women were available for analysis. Exercise-DVD was the most expensive and least effective intervention. Exercise-Social support was £52 (CIs: £18 to £86) and £18 (CIs: -£68 to £105) more expensive per woman than the control group at 6 and 12 months post-randomisation and led to 0.006 (CIs: -0.002 to 0.014) and 0.013 (CIs: -0.01 to 0.036) more QALYs, resulting in an incremental cost-effectiveness ratio of £8,940 and £1,413 per QALY gained respectively. Exercise-Social support had 80%-90% probability of being cost-effective in the UK context. A societal perspective of analysis and a complete-case analysis led to similar findings. Exercise-Social support resulted in a small gain in health-related quality of life at a marginal additional cost in a context where broader wellbeing and long-term gains associated with exercise and social participation were not captured. Community exercise social support groups are very likely to be cost-effective in the management of vasomotor menopausal symptoms.

  7. Aerobic exercise for vasomotor menopausal symptoms: A cost-utility analysis based on the Active Women trial

    PubMed Central

    Goranitis, Ilias; Bellanca, Leana; Daley, Amanda J.; Thomas, Adele; Stokes-Lampard, Helen; Roalfe, Andrea K.

    2017-01-01

    Objective To compare the cost-utility of two exercise interventions relative to a control group for vasomotor menopausal symptoms. Design Economic evaluation taking a UK National Health Service and Personal Social Services perspective and a societal perspective. Setting Primary care. Population Peri- and postmenopausal women who have not used hormone therapy in the past 3 months and experience ≥ 5 episodes of vasomotor symptoms daily. Methods An individual and a social support-based exercise intervention were evaluated. The former (Exercise-DVD), aimed to prompt exercise with purpose-designed DVD and written materials, whereas the latter (Exercise-Social support) with community exercise social support groups. Costs and outcomes associated with these interventions were compared to those of a control group, who could only have an exercise consultation. An incremental cost-utility analysis was undertaken using bootstrapping to account for the uncertainty around cost-effectiveness point-estimates. Main outcome measure Cost per quality-adjusted life-year (QALY). Results Data for 261 women were available for analysis. Exercise-DVD was the most expensive and least effective intervention. Exercise-Social support was £52 (CIs: £18 to £86) and £18 (CIs: -£68 to £105) more expensive per woman than the control group at 6 and 12 months post-randomisation and led to 0.006 (CIs: -0.002 to 0.014) and 0.013 (CIs: -0.01 to 0.036) more QALYs, resulting in an incremental cost-effectiveness ratio of £8,940 and £1,413 per QALY gained respectively. Exercise-Social support had 80%-90% probability of being cost-effective in the UK context. A societal perspective of analysis and a complete-case analysis led to similar findings. Conclusions Exercise-Social support resulted in a small gain in health-related quality of life at a marginal additional cost in a context where broader wellbeing and long-term gains associated with exercise and social participation were not captured. Community exercise social support groups are very likely to be cost-effective in the management of vasomotor menopausal symptoms. PMID:28949974

  8. 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.

  9. 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.

  10. [Effect of techniques of composite resin insertion and polymerization on microleakage and microhardness].

    PubMed

    Amaral, Cristiane Mariote; Castro, Ana Karina Barbieri Bedran de; Pimenta, Luiz André Freire; Ambrosano, Glaucia Maria Boni

    2002-01-01

    The aim of this study was to evaluate the influence of techniques of composite resin polymerization and insertion on microleakage and microhardness. One hundred and eighty class II cavities were prepared in bovine teeth and assigned to six groups: G1 - bulk filling + conventional polymerization; G2 - bucco-lingual increments + conventional polymerization; G3 - bulk filling + soft-start polymerization; G4 - bucco-lingual increments + soft-start polymerization; G5 - bulk filling + progressive polymerization; G6 - bucco-lingual increments + progressive polymerization. All cavities were restored with the Z100/Single Bond system (3M). After thermocycling, the samples were immersed in 2% methylene blue dye solution for 4 hours. Half of the samples were embedded in polystyrene resin, and Knoop microhardness was measured. The Kruskal-Wallis test did not reveal statistical differences (p > 0.05) between the polymerization and insertion techniques as to microleakage. Regarding microhardness, the two-way ANOVA and the Tukey test did not reveal statistical differences between the restorative techniques (p > 0.05), but progressive polymerization (G5 and G6) was associated with smaller Knoop microhardness values (p < 0.05): G = 144.11; G2 = 143.89; G3 = 141.14; G4 = 142.79; G5 = 132.15; G6 = 131.67. It was concluded that the evaluated polymerization and insertion techniques did not affect marginal microleakage, but a decrease in microhardness occurred when progressive polymerization was carried out.

  11. A Parallel and Incremental Approach for Data-Intensive Learning of Bayesian Networks.

    PubMed

    Yue, Kun; Fang, Qiyu; Wang, Xiaoling; Li, Jin; Liu, Weiyi

    2015-12-01

    Bayesian network (BN) has been adopted as the underlying model for representing and inferring uncertain knowledge. As the basis of realistic applications centered on probabilistic inferences, learning a BN from data is a critical subject of machine learning, artificial intelligence, and big data paradigms. Currently, it is necessary to extend the classical methods for learning BNs with respect to data-intensive computing or in cloud environments. In this paper, we propose a parallel and incremental approach for data-intensive learning of BNs from massive, distributed, and dynamically changing data by extending the classical scoring and search algorithm and using MapReduce. First, we adopt the minimum description length as the scoring metric and give the two-pass MapReduce-based algorithms for computing the required marginal probabilities and scoring the candidate graphical model from sample data. Then, we give the corresponding strategy for extending the classical hill-climbing algorithm to obtain the optimal structure, as well as that for storing a BN by pairs. Further, in view of the dynamic characteristics of the changing data, we give the concept of influence degree to measure the coincidence of the current BN with new data, and then propose the corresponding two-pass MapReduce-based algorithms for BNs incremental learning. Experimental results show the efficiency, scalability, and effectiveness of our methods.

  12. Shifting policy responses to domestic violence in the Netherlands and Spain (1980-2009).

    PubMed

    Roggeband, Conny

    2012-07-01

    This article seeks to understand differences in the evolution of policies to combat domestic violence against women in the Netherlands and Spain. Although policy change is often viewed as incremental change toward more progressive policies, the two countries studied here reflect opposing dynamics. The Netherlands moved from being a pioneering country to one that gradually marginalized the policy issue, whereas Spain, in contrast, recently developed innovative and far-reaching policies after a long period of low to moderate state responses. The case study points to the central role of frame negotiation, left-wing governments, and strong feminist mobilization.

  13. Significance and outcome of nuclear anaplasia and mitotic index in prostatic adenocarcinomas.

    PubMed

    Kır, Gozde; Sarbay, Billur Cosan; Gumus, Eyup

    2016-10-01

    The Gleason grading system measures architectural differentiation and disregards nuclear atypia and the cell proliferation index. Several studies have reported that nuclear grade and mitotic index (MI) are prognostically useful. This study included 232 radical prostatectomy specimens. Nuclear anaplasia (NA) was determined on the basis of nucleomegali (at least 20µm); vesicular chromatin; eosinophilic macronucleoli, nuclear lobulation, and irregular thickened nuclear membranei. The proportion of area of NA was recorded in each tumor in 10% increments. The MI was defined as the number of mitotic figures in 10 consecutive high-power fields (HPF). In univariate analysis, significant differences included associations between biochemical prostate-specific antigen recurrence (BCR) and Gleason score, extraprostatic extension, positive surgical margin, the presence of high-pathologic stage, NA≥10% of tumor area, MI≥3/10 HPF, and preoperative prostate-specific antigen. In a stepwise Cox regression model, a positive surgical margin, the presence of a NA≥10% of tumor area, and a MI of≥3/10 HPF were independent predictors of BCR after radical prostatectomy. NA≥10% of tumor area appeared to have a stronger association with outcome than MI≥3/10 HPF, as still associated with BCR when Gleason score was in the model. The results of our study showed that, in addition to the conventional Gleason grading system, NA, and MI are useful prognostic parameters while evaluating long-term prognosis in prostatic adenocarcinoma. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Precipitable water vapor budget associated with MJO represented in newly-released JRA-55 reanalysis data

    NASA Astrophysics Data System (ADS)

    Yokoi, S.

    2013-12-01

    The Japan Meteorological Agency (JMA) recently released a new reanalysis dataset JRA-55 with the use of a JMA operational prediction model and 4D-VAR data assimilation. To evaluate merit in utilizing the JRA-55 dataset to investigate dynamics of the tropical intraseasonal variability (ISV) including the Madden-Julian Oscillation (MJO), this study examines ISV-scale precipitable water vapor (PWV) budget over the period 1989-2012. The ISV-scale PWV anomaly related to the boreal-winter MJO propagates eastward along with precipitation, consistent with the SSM/I PWV product. Decomposition of the PWV tendency into that simulated by the model and the analysis increment estimated by the data assimilation reveals that the model makes the PWV anomaly move eastward. On the other hand, the analysis increment exhibits positive values over the area where the PWV anomaly is positive, indicating that the model tends to damp the MJO signal. Note that the analysis increment over the Maritime Continent has comparable magnitude to the model tendency. The positive analysis increment may mainly be caused by an excess of precipitation anomaly with respect to the magnitude of PWV anomaly. In addition to the boreal-winter MJO, this study also examines the PWV budget associated with northward-propagating ISV during the boreal summer and find similar relationship between the PWV anomaly and analysis increment.

  15. Constructing increment-decrement life tables.

    PubMed

    Schoen, R

    1975-05-01

    A life table model which can recognize increments (or entrants) as well as decrements has proven to be of considerable value in the analysis of marital status patterns, labor force participation patterns, and other areas of substantive interest. Nonetheless, relatively little work has been done on the methodology of increment-decrement (or combined) life tables. The present paper reviews the general, recursive solution of Schoen and Nelson (1974), develops explicit solutions for three cases of particular interest, and compares alternative approaches to the construction of increment-decrement tables.

  16. CF6 jet engine performance deterioration results

    NASA Technical Reports Server (NTRS)

    Lewis, R. J.; Humerickhouse, C. E.; Paas, J. E.

    1978-01-01

    The use of the performance baseline from the flight planning manual as a reference to measure changes in cruise fuel flow rates was discussed. For the CF6-6D engine, the introduction of design changes for performance and durability reasons was seen to introduce an average increment relative to this baseline of 3.2% WFM increase at Nl, 2.5% Fn increase at Nl, 0.8% specific fuel consumption (SFC) increase at Fn, and 7 C EGT increase at Nl, while maintaining sufficient SFC margin of the delivered airplane. The effect of revenue service deterioration and performance restoration relative to the reference was shown to be an adder on top of these design effects. A schematic of typical CF6-6D performance through revenue service and airline maintenance is presented in terms of percent cruise SFC relative to an airline datum point (average level upon entering revenue service). The typical changes in SFC margin are shown for airline revenue service through for installations and refurbishments.

  17. Economic evaluation of distribution system smart grid investments

    DOE PAGES

    Onen, Ahmet; Cheng, Danling; Broadwater, Robert P.; ...

    2014-12-31

    This paper investigates economic benefits of smart grid automation investments. A system consisting of 7 substations and 14 feeders is used in the evaluation. Here benefits that can be quantified in terms of dollar savings are considered, termed “hard dollar” benefits. Smart Grid investment evaluations to be considered include investments in improved efficiency, more cost effective use of existing system capacity with automated switches, and coordinated control of capacitor banks and voltage regulators. These Smart Grid evaluations are sequentially ordered, resulting in a series of incremental hard dollar benefits. Hard dollar benefits come from improved efficiency, delaying large capital equipmentmore » investments, shortened storm restoration times, and reduced customer energy use. Analyses used in the evaluation involve hourly power flow analysis over multiple years and Monte Carlo simulations of switching operations during storms using a reconfiguration for restoration algorithm. The economic analysis uses the time varying value of the Locational Marginal Price. Algorithms used include reconfiguration for restoration involving either manual or automated switches and coordinated control involving two modes of control. Field validations of phase balancing and capacitor design results are presented. The evaluation shows that investments in automation can improve performance while at the same time lowering costs.« less

  18. Cost-effectiveness of condom uterine balloon tamponade to control severe postpartum hemorrhage in Kenya.

    PubMed

    Mvundura, Mercy; Kokonya, Donald; Abu-Haydar, Elizabeth; Okoth, Eunice; Herrick, Tara; Mukabi, James; Carlson, Lucas; Oguttu, Monica; Burke, Thomas

    2017-05-01

    To evaluate the cost-effectiveness of condom uterine balloon tamponade (UBT) for control of severe postpartum hemorrhage (PPH) due to uterine atony versus standard PPH care in Kenya. A cross-sectional analysis was conducted using cost data collected from 30 facilities in Western Kenya from April 15 to July 16, 2015. Effectiveness data were derived from the published literature. The modeling analysis was performed from the health-system perspective for a cohort of women who gave birth in 2015. Sensitivity analyses tested the robustness of model estimates. Costs were in 2015 US dollars. Compared with standard care with no uterine packing, condom UBT could prevent 1255 hospital transfers, 430 hysterectomies, and 44 maternal deaths. At $5 or $15 per UBT device, the incremental cost per disability-adjusted life year (DALY) averted was $26 or $40, respectively. If uterine packing was assumed to be done with standard care, the cost per DALY averted was $164 when the UBT price was $5 and $199 when the price was $15. Condom UBT was a highly cost-effective intervention for controlling severe PPH. This finding remained robust even when key model inputs were varied by wide margins. © 2017 International Federation of Gynecology and Obstetrics.

  19. 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.

  20. Something old, something new, something borrowed, something blue: a framework for the marriage of health econometrics and cost-effectiveness analysis.

    PubMed

    Hoch, Jeffrey S; Briggs, Andrew H; Willan, Andrew R

    2002-07-01

    Economic evaluation is often seen as a branch of health economics divorced from mainstream econometric techniques. Instead, it is perceived as relying on statistical methods for clinical trials. Furthermore, the statistic of interest in cost-effectiveness analysis, the incremental cost-effectiveness ratio is not amenable to regression-based methods, hence the traditional reliance on comparing aggregate measures across the arms of a clinical trial. In this paper, we explore the potential for health economists undertaking cost-effectiveness analysis to exploit the plethora of established econometric techniques through the use of the net-benefit framework - a recently suggested reformulation of the cost-effectiveness problem that avoids the reliance on cost-effectiveness ratios and their associated statistical problems. This allows the formulation of the cost-effectiveness problem within a standard regression type framework. We provide an example with empirical data to illustrate how a regression type framework can enhance the net-benefit method. We go on to suggest that practical advantages of the net-benefit regression approach include being able to use established econometric techniques, adjust for imperfect randomisation, and identify important subgroups in order to estimate the marginal cost-effectiveness of an intervention. Copyright 2002 John Wiley & Sons, Ltd.

  1. Aerodynamic Analyses and Database Development for Ares I Vehicle First Stage Separation

    NASA Technical Reports Server (NTRS)

    Pamadi, Bandu N.; Pei, Jing; Pinier, Jeremy T.; Klopfer, Goetz H.; Holland, Scott D.; Covell, Peter F.

    2011-01-01

    This paper presents the aerodynamic analysis and database development for first stage separation of Ares I A106 crew launch vehicle configuration. Separate 6-DOF databases were created for the first stage and upper stage and each database consists of three components: (a) isolated or freestream coefficients, (b) power-off proximity increments, and (c) power-on proximity increments. The isolated and power-off incremental databases were developed using data from 1% scaled model tests in AEDC VKF Tunnel A. The power-on proximity increments were developed using OVERFLOW CFD solutions. The database also includes incremental coefficients for one BDM and one USM failure scenarios.

  2. Incremental analysis of large elastic deformation of a rotating cylinder

    NASA Technical Reports Server (NTRS)

    Buchanan, G. R.

    1976-01-01

    The effect of finite deformation upon a rotating, orthotropic cylinder was investigated using a general incremental theory. The incremental equations of motion are developed using the variational principle. The governing equations are derived using the principle of virtual work for a body with initial stress. The governing equations are reduced to those for the title problem and a numerical solution is obtained using finite difference approximations. Since the problem is defined in terms of one independent space coordinate, the finite difference grid can be modified as the incremental deformation occurs without serious numerical difficulties. The nonlinear problem is solved incrementally by totaling a series of linear solutions.

  3. Cost-effectiveness of rituximab (MabThera) in diffuse large B-cell lymphoma in The Netherlands.

    PubMed

    Groot, M T; Lugtenburg, P J; Hornberger, J; Huijgens, P C; Uyl-de Groot, C A

    2005-03-01

    To determine the incremental cost-effectiveness ratio (ICER) of cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) vs. CHOP plus rituximab (R-CHOP) in diffuse large B-cell lymphoma (DLBCL) patients in the Netherlands. A state transition model was developed to estimate the clinical course, costs and quality of life of patients with stage II, III or IV DLBCL receiving initial treatment with CHOP or R-CHOP to arrive at the ICER. The base year for the cost analysis was 2002 and was performed from the societal perspective. Only direct medical costs were included. The time horizon of the model was 15 yr and both costs and effects were discounted at 4%. Sensitivity analyses were performed to determine the effect of varying base-line assumptions of the model. The incremental gain in quality adjusted life years (QALYs) was 0.88 in both the younger and the older patient groups. The costs were 12 343 higher in the younger group of patients and 15 860 in the older patients. This resulted in an ICER of 13 983 for the younger and 17 933 for the older patients per QALY gained. These results were sensitive to the time horizon of the model, other variations had a marginal impact on the outcome. The addition of rituximab to standard therapy for DLBCL results in a gain of 0.88 QALYs. The ICER of 13 983 for younger and 17 933 for older patients per QALY gained should, seen in the light of disease severity, be considered acceptable by most policy makers in priority setting for budget allocation.

  4. The cost-effectiveness of hepatic venous pressure gradient monitoring in the prevention of recurrent variceal hemorrhage.

    PubMed

    Targownik, Laura E; Spiegel, Brennan M R; Dulai, Gareth S; Karsan, Hetal A; Gralnek, Ian M

    2004-07-01

    Recurrent variceal hemorrhage is common following an initial bleed in patients with cirrhosis. The current standard of care for secondary prophylaxis is endoscopic band ligation (EBL). Combination of beta-blocker and nitrate therapy, guided by hepatic venous pressure gradient (HVPG) monitoring, is a novel alternative strategy. We sought to determine the cost-effectiveness of these competing strategies. Decision analysis with Markov modeling was used to calculate the cost-effectiveness of three competing strategies: (1) EBL; (2) beta-blocker and nitrate therapy without HVPG monitoring (HVPG-); and (3) beta-blocker and nitrate therapy with HVPG monitoring (HVPG+). Patients in the HVPG+ strategy who failed to achieve an HVPG decline from medical therapy were offered EBL. Cost estimates were from a third-party payer perspective. The main outcome measure was the cost per recurrent variceal hemorrhage prevented. Under base-case conditions, the HVPG+ strategy was the most effective yet most expensive approach, followed by EBL and HVPG-. Compared to the EBL strategy, the HVPG+ strategy cost an incremental 5,974 dollars per recurrent bleed prevented. In a population with 100% compliance with all therapies, the incremental cost of HVPG-versus EBL fell to 5,270 dollars per recurrent bleed prevented. The model results were sensitive to the cost of EBL, the cost of HVPG monitoring, and the probability of medical therapy producing an adequate HVPG decline. Compared to EBL for the secondary prophylaxis of variceal rebleeding, combination medical therapy guided by HVPG monitoring is more effective and only marginally more expensive.

  5. Estimating the Depth of Stratigraphic Units from Marine Seismic Profiles Using Nonstationary Geostatistics

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

    Chihi, Hayet; Galli, Alain; Ravenne, Christian

    2000-03-15

    The object of this study is to build a three-dimensional (3D) geometric model of the stratigraphic units of the margin of the Rhone River on the basis of geophysical investigations by a network of seismic profiles at sea. The geometry of these units is described by depth charts of each surface identified by seismic profiling, which is done by geostatistics. The modeling starts by a statistical analysis by which we determine the parameters that enable us to calculate the variograms of the identified surfaces. After having determined the statistical parameters, we calculate the variograms of the variable Depth. By analyzingmore » the behavior of the variogram we then can deduce whether the situation is stationary and if the variable has an anisotropic behavior. We tried the following two nonstationary methods to obtain our estimates: (a) The method of universal kriging if the underlying variogram was directly accessible. (b) The method of increments if the underlying variogram was not directly accessible. After having modeled the variograms of the increments and of the variable itself, we calculated the surfaces by kriging the variable Depth on a small-mesh estimation grid. The two methods then are compared and their respective advantages and disadvantages are discussed, as well as their fields of application. These methods are capable of being used widely in earth sciences for automatic mapping of geometric surfaces or for variables such as a piezometric surface or a concentration, which are not 'stationary,' that is, essentially, possess a gradient or a tendency to develop systematically in space.« less

  6. Need for a marginal methodology in assessing natural gas system methane emissions in response to incremental consumption.

    PubMed

    Mac Kinnon, Michael; Heydarzadeh, Zahra; Doan, Quy; Ngo, Cuong; Reed, Jeff; Brouwer, Jacob

    2018-05-17

    Accurate quantification of methane emissions from the natural gas system is important for establishing greenhouse gas inventories and understanding cause and effect for reducing emissions. Current carbon intensity methods generally assume methane emissions are proportional to gas throughput so that increases in gas consumption yield linear increases in emitted methane. However, emissions sources are diverse and many are not proportional to throughput. Insights into the causal drivers of system methane emissions, and how system-wide changes affect such drivers are required. The development of a novel cause-based methodology to assess marginal methane emissions per unit of fuel consumed is introduced. The carbon intensities of technologies consuming natural gas are critical metrics currently used in policy decisions for reaching environmental goals. For example, the low-carbon fuel standard in California uses carbon intensity to determine incentives provided. Current methods generally assume methane emissions from the natural gas system are completely proportional to throughput. The proposed cause-based marginal emissions method will provide a better understanding of the actual drivers of emissions to support development of more effective mitigation measures. Additionally, increasing the accuracy of carbon intensity calculations supports the development of policies that can maximize the environmental benefits of alternative fuels, including reducing greenhouse gas emissions.

  7. Adiabatic elimination of inertia of the stochastic microswimmer driven by α -stable noise

    NASA Astrophysics Data System (ADS)

    Noetel, Joerg; Sokolov, Igor M.; Schimansky-Geier, Lutz

    2017-10-01

    We consider a microswimmer that moves in two dimensions at a constant speed and changes the direction of its motion due to a torque consisting of a constant and a fluctuating component. The latter will be modeled by a symmetric Lévy-stable (α -stable) noise. The purpose is to develop a kinetic approach to eliminate the angular component of the dynamics to find a coarse-grained description in the coordinate space. By defining the joint probability density function of the position and of the orientation of the particle through the Fokker-Planck equation, we derive transport equations for the position-dependent marginal density, the particle's mean velocity, and the velocity's variance. At time scales larger than the relaxation time of the torque τϕ, the two higher moments follow the marginal density and can be adiabatically eliminated. As a result, a closed equation for the marginal density follows. This equation, which gives a coarse-grained description of the microswimmer's positions at time scales t ≫τϕ , is a diffusion equation with a constant diffusion coefficient depending on the properties of the noise. Hence, the long-time dynamics of a microswimmer can be described as a normal, diffusive, Brownian motion with Gaussian increments.

  8. Adiabatic elimination of inertia of the stochastic microswimmer driven by α-stable noise.

    PubMed

    Noetel, Joerg; Sokolov, Igor M; Schimansky-Geier, Lutz

    2017-10-01

    We consider a microswimmer that moves in two dimensions at a constant speed and changes the direction of its motion due to a torque consisting of a constant and a fluctuating component. The latter will be modeled by a symmetric Lévy-stable (α-stable) noise. The purpose is to develop a kinetic approach to eliminate the angular component of the dynamics to find a coarse-grained description in the coordinate space. By defining the joint probability density function of the position and of the orientation of the particle through the Fokker-Planck equation, we derive transport equations for the position-dependent marginal density, the particle's mean velocity, and the velocity's variance. At time scales larger than the relaxation time of the torque τ_{ϕ}, the two higher moments follow the marginal density and can be adiabatically eliminated. As a result, a closed equation for the marginal density follows. This equation, which gives a coarse-grained description of the microswimmer's positions at time scales t≫τ_{ϕ}, is a diffusion equation with a constant diffusion coefficient depending on the properties of the noise. Hence, the long-time dynamics of a microswimmer can be described as a normal, diffusive, Brownian motion with Gaussian increments.

  9. The availability and marginal costs of dependent employer-sponsored health insurance.

    PubMed

    Miller, G Edward; Vistnes, Jessica; Buettgens, Matthew; Dubay, Lisa

    2017-01-21

    In this study, we examine differences by firm size in the availability of dependent coverage and the incremental cost of such coverage. We use data from the Medical Expenditure Panel Survey - Insurance Component (MEPS-IC) to show that among employees eligible for single coverage, dependent coverage was almost always available for employees in large firms (100 or more employees) but not in smaller firms, particularly those with fewer than 10 employees. In addition, when dependent coverage was available, eligible employees in smaller firms were more likely than employees in large firms to face two situations that represented the extremes of the incremental cost distribution: (1) they paid nothing for single or family coverage or (2) they paid nothing for single coverage but faced a high contribution for family coverage. These results suggest that firm size may be an important factor in policy assessments, such as analyses of the financial implications for families excluded from subsidized Marketplace coverage due to affordable offers of single coverage or of potential rollbacks to public coverage for children.

  10. Size, Stability and Incremental Budgeting Outcomes in Public Universities.

    ERIC Educational Resources Information Center

    Schick, Allen G.; Hills, Frederick S.

    1982-01-01

    Examined the influence of relative size in the analysis of total dollar and workforce budgets, and changes in total dollar and workforce budgets when correlational/regression methods are used. Data suggested that size dominates the analysis of total budgets, and is not a factor when discretionary dollar increments are analyzed. (JAC)

  11. A new universal simplified adhesive: 6-month clinical evaluation.

    PubMed

    Mena-Serrano, Alexandra; Kose, Carlos; De Paula, Eloisa Andrade; Tay, Lidia Yileng; Reis, Alessandra; Loguercio, Alessandro D; Perdigão, Jorge

    2013-02-01

    Multimode adhesives, which can be used as etch-and-rinse or as self-etch adhesives, have been recently introduced without clinical data to back their use. To evaluate the 6-month clinical performance of Scotchbond Universal Adhesive (SU; 3M ESPE, St. Paul, MN, USA) in noncarious cervical lesions (NCCLs) using two evaluation criteria. Thirty-nine patients participated in this study. Two hundred restorations were assigned to four groups: SU-TEm: etch-and-rinse + moist dentin; SU-TEd: etch-and-rinse + dry dentin; SU-SEet: selective enamel etching; and SU-SE: self-etch. The composite resin Filtek Supreme Ultra (3M ESPE) was placed incrementally. The restorations were evaluated at baseline and after 6 months using both the World Dental Federation (FDI) and the United States Public Health Service (USPHS) criteria. Statistical analyses were performed with Friedman repeated measures analysis of variance by rank and McNemar test for significance in each pair (α = 0.05). Only four restorations (SU-SE: 3 and SU-TEm: 1) were lost after 6 months (p > 0.05 for either criteria). Marginal discoloration occurred in one restoration in the SU-SE group (p > 0.05 for either criteria). Only 2/200 restorations were scored as bravo for marginal adaptation using the USPHS criteria (one for SU-SE and one for SU-SEet, p > 0.05). However, when using the FDI criteria, the percentage of bravo scores for marginal adaptation at 6 months were 32%, 36%, 42%, and 46% for groups SU-TEm, SU-TEd, SU-SEet, and SU-SE, respectively (p > 0.05). The clinical behavior of the multimode adhesive does not depend on the bonding strategy at 6 months. The FDI evaluation criteria are more sensitive than the USPHS criteria. At 6 months, the clinical behavior of the new multimode adhesive Scotchbond Universal was found to be reliable when used in noncarious cervical lesions and may not depend on the bonding strategy employed. © 2012 Wiley Periodicals, Inc.

  12. Inventory-based sensitivity analysis of the Large Tree Diameter Growth Submodel of the Southern Variant of the FVS

    Treesearch

    Giorgio Vacchiano; John D. Shaw; R. Justin DeRose; James N. Long

    2008-01-01

    Diameter increment is an important variable in modeling tree growth. Most facets of predicted tree development are dependent in part on diameter or diameter increment, the most commonly measured stand variable. The behavior of the Forest Vegetation Simulator (FVS) largely relies on the performance of the diameter increment model and the subsequent use of predicted dbh...

  13. Analysis and application of two-current-source circuit as a signal conditioner for resistive sensors

    NASA Astrophysics Data System (ADS)

    Idzkowski, Adam; Gołębiowski, Jerzy; Walendziuk, Wojciech

    2017-05-01

    The article presents the analysis of metrological properties of a two-current-source supplied circuit. It includes such data as precise and simplified equations for two circuit output voltages in the function of relative resistance increments of sensors. Moreover, graphs showing nonlinearity coefficients of both output voltages for two resistance increments varying widely are presented. Graphs of transfer resistances, depending on relative increments of sensors resistance were also created. The article also contains a description of bridge-based circuit realization with the use of a computer and a data acquisition (DAQ) card. Laboratory measurement of the difference and sum of relative resistance increments of two resistance decade boxes were carried out indirectly with the use of the created measurement system. Measurement errors were calculated and included in the article, as well.

  14. Martingales, nonstationary increments, and the efficient market hypothesis

    NASA Astrophysics Data System (ADS)

    McCauley, Joseph L.; Bassler, Kevin E.; Gunaratne, Gemunu H.

    2008-06-01

    We discuss the deep connection between nonstationary increments, martingales, and the efficient market hypothesis for stochastic processes x(t) with arbitrary diffusion coefficients D(x,t). We explain why a test for a martingale is generally a test for uncorrelated increments. We explain why martingales look Markovian at the level of both simple averages and 2-point correlations. But while a Markovian market has no memory to exploit and cannot be beaten systematically, a martingale admits memory that might be exploitable in higher order correlations. We also use the analysis of this paper to correct a misstatement of the ‘fair game’ condition in terms of serial correlations in Fama’s paper on the EMH. We emphasize that the use of the log increment as a variable in data analysis generates spurious fat tails and spurious Hurst exponents.

  15. Space-time quantitative source apportionment of soil heavy metal concentration increments.

    PubMed

    Yang, Yong; Christakos, George; Guo, Mingwu; Xiao, Lu; Huang, Wei

    2017-04-01

    Assessing the space-time trends and detecting the sources of heavy metal accumulation in soils have important consequences in the prevention and treatment of soil heavy metal pollution. In this study, we collected soil samples in the eastern part of the Qingshan district, Wuhan city, Hubei Province, China, during the period 2010-2014. The Cd, Cu, Pb and Zn concentrations in soils exhibited a significant accumulation during 2010-2014. The spatiotemporal Kriging technique, based on a quantitative characterization of soil heavy metal concentration variations in terms of non-separable variogram models, was employed to estimate the spatiotemporal soil heavy metal distribution in the study region. Our findings showed that the Cd, Cu, and Zn concentrations have an obvious incremental tendency from the southwestern to the central part of the study region. However, the Pb concentrations exhibited an obvious tendency from the northern part to the central part of the region. Then, spatial overlay analysis was used to obtain absolute and relative concentration increments of adjacent 1- or 5-year periods during 2010-2014. The spatial distribution of soil heavy metal concentration increments showed that the larger increments occurred in the center of the study region. Lastly, the principal component analysis combined with the multiple linear regression method were employed to quantify the source apportionment of the soil heavy metal concentration increments in the region. Our results led to the conclusion that the sources of soil heavy metal concentration increments should be ascribed to industry, agriculture and traffic. In particular, 82.5% of soil heavy metal concentration increment during 2010-2014 was ascribed to industrial/agricultural activities sources. Using STK and SOA to obtain the spatial distribution of heavy metal concentration increments in soils. Using PCA-MLR to quantify the source apportionment of soil heavy metal concentration increments. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Cost-effectiveness of an Evidence-Based Childhood Asthma Intervention in Real-World Primary Care Settings.

    PubMed

    Dor, Avi; Luo, Qian; Gerstein, Maya Tuchman; Malveaux, Floyd; Mitchell, Herman; Markus, Anne Rossier

    We present an incremental cost-effectiveness analysis of an evidence-based childhood asthma intervention (Community Healthcare for Asthma Management and Prevention of Symptoms [CHAMPS]) to usual management of childhood asthma in community health centers. Data used in the analysis include household surveys, Medicaid insurance claims, and community health center expenditure reports. We combined our incremental cost-effectiveness analysis with a difference-in-differences multivariate regression framework. We found that CHAMPS reduced symptom days by 29.75 days per child-year and was cost-effective (incremental cost-effectiveness ratio: $28.76 per symptom-free days). Most of the benefits were due to reductions in direct medical costs. Indirect benefits from increased household productivity were relatively small.

  17. A manned Mars mission concept with artificial gravity

    NASA Technical Reports Server (NTRS)

    Davis, Hubert P.

    1986-01-01

    A series of simulated manned Mars missions was analyzed by a computer model. Numerous mission opportunities and mission modes were investigated. Sensitivity trade studies were performed of the vehicle all-up mass and propulsion stage sizes as a function of various levels of conservatism in mission velocity increment margins, payload mass and propulsive stage characteristics. The longer duration but less energetic type of conjunction class mission is emphasized. The specific mission opportunity reviewed was for a 1997 departure. From the trade study results, a three and one-half stage vehicle concept evolved, utilizing a Trans-Mars Injection (TMI) first stage derived from the Space Shuttle External Tank (ET).

  18. Cost Effectiveness of Alectinib vs. Crizotinib in First-Line Anaplastic Lymphoma Kinase-Positive Advanced Non-Small-Cell Lung Cancer.

    PubMed

    Carlson, Josh J; Suh, Kangho; Orfanos, Panos; Wong, William

    2018-04-01

    The recently completed ALEX trial demonstrated that alectinib improved progression-free survival, and delayed time to central nervous system progression compared with crizotinib in patients with anaplastic lymphoma kinase-positive non-small-cell lung cancer. However, the long-term clinical and economic impact of using alectinib vs. crizotinib has not been evaluated. The objective of this study was to determine the potential cost utility of alectinib vs. crizotinib from a US payer perspective. A cost-utility model was developed using partition survival methods and three health states: progression-free, post-progression, and death. ALEX trial data informed the progression-free and overall survival estimates. Costs included drug treatments and supportive care (central nervous system and non-central nervous system). Utility values were obtained from trial data and literature. Sensitivity analyses included one-way and probabilistic sensitivity analyses. Treatment with alectinib vs. crizotinib resulted in a gain of 0.91 life-years, 0.87 quality-adjusted life-years, and incremental costs of US$34,151, resulting in an incremental cost-effectiveness ratio of US$39,312/quality-adjusted life-year. Drug costs and utilities in the progression-free health state were the main drivers of the model in the one-way sensitivity analysis. From the probabilistic sensitivity analysis, alectinib had a 64% probability of being cost effective at a willingness-to-pay threshold of US$100,000/quality adjusted life-year. Alectinib increased time in the progression-free state and quality-adjusted life-years vs. crizotinib. The marginal cost increase was reflective of longer treatment durations in the progression-free state. Central nervous system-related costs were considerably lower with alectinib. Our results suggest that compared with crizotinib, alectinib may be a cost-effective therapy for treatment-naïve patients with anaplastic lymphoma kinase-positive non-small-cell lung cancer.

  19. Using Analysis Increments (AI) to Estimate and Correct Systematic Errors in the Global Forecast System (GFS) Online

    NASA Astrophysics Data System (ADS)

    Bhargava, K.; Kalnay, E.; Carton, J.; Yang, F.

    2017-12-01

    Systematic forecast errors, arising from model deficiencies, form a significant portion of the total forecast error in weather prediction models like the Global Forecast System (GFS). While much effort has been expended to improve models, substantial model error remains. The aim here is to (i) estimate the model deficiencies in the GFS that lead to systematic forecast errors, (ii) implement an online correction (i.e., within the model) scheme to correct GFS following the methodology of Danforth et al. [2007] and Danforth and Kalnay [2008, GRL]. Analysis Increments represent the corrections that new observations make on, in this case, the 6-hr forecast in the analysis cycle. Model bias corrections are estimated from the time average of the analysis increments divided by 6-hr, assuming that initial model errors grow linearly and first ignoring the impact of observation bias. During 2012-2016, seasonal means of the 6-hr model bias are generally robust despite changes in model resolution and data assimilation systems, and their broad continental scales explain their insensitivity to model resolution. The daily bias dominates the sub-monthly analysis increments and consists primarily of diurnal and semidiurnal components, also requiring a low dimensional correction. Analysis increments in 2015 and 2016 are reduced over oceans, which is attributed to improvements in the specification of the SSTs. These results encourage application of online correction, as suggested by Danforth and Kalnay, for mean, seasonal and diurnal and semidiurnal model biases in GFS to reduce both systematic and random errors. As the error growth in the short-term is still linear, estimated model bias corrections can be added as a forcing term in the model tendency equation to correct online. Preliminary experiments with GFS, correcting temperature and specific humidity online show reduction in model bias in 6-hr forecast. This approach can then be used to guide and optimize the design of sub-grid scale physical parameterizations, more accurate discretization of the model dynamics, boundary conditions, radiative transfer codes, and other potential model improvements which can then replace the empirical correction scheme. The analysis increments also provide guidance in testing new physical parameterizations.

  20. Longitudinal Aerodynamic Modeling of the Adaptive Compliant Trailing Edge Flaps on a GIII Airplane and Comparisons to Flight Data

    NASA Technical Reports Server (NTRS)

    Smith, Mark S.; Bui, Trong T.; Garcia, Christian A.; Cumming, Stephen B.

    2016-01-01

    A pair of compliant trailing edge flaps was flown on a modified GIII airplane. Prior to flight test, multiple analysis tools of various levels of complexity were used to predict the aerodynamic effects of the flaps. Vortex lattice, full potential flow, and full Navier-Stokes aerodynamic analysis software programs were used for prediction, in addition to another program that used empirical data. After the flight-test series, lift and pitching moment coefficient increments due to the flaps were estimated from flight data and compared to the results of the predictive tools. The predicted lift increments matched flight data well for all predictive tools for small flap deflections. All tools over-predicted lift increments for large flap deflections. The potential flow and Navier-Stokes programs predicted pitching moment coefficient increments better than the other tools.

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

    NASA Technical Reports Server (NTRS)

    Nguyen, Nhan T.; Boskovic, Jovan D.

    2008-01-01

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

  2. 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.

  3. Theater Medical Information Program Joint Increment 2 (TMIP J Inc 2)

    DTIC Science & Technology

    2016-03-01

    Acquisition Executive DoD - Department of Defense DoDAF - DoD Architecture Framework FD - Full Deployment FDD - Full Deployment Decision FY...the Full Deployment Decision ( FDD ), the TMIP-J Increment 2 Economic Analysis was approved on December 6, 2013. The USD(AT&L) signed an Acquisition...Decision Memorandum (ADM) on December 23, 2013 approving FDD for TMIP-J Increment 2 and establishing the Full Deployment Objective and Threshold dates as

  4. Cost-Effectiveness of Endovascular Stroke Therapy: A Patient Subgroup Analysis From a US Healthcare Perspective.

    PubMed

    Kunz, Wolfgang G; Hunink, M G Myriam; Sommer, Wieland H; Beyer, Sebastian E; Meinel, Felix G; Dorn, Franziska; Wirth, Stefan; Reiser, Maximilian F; Ertl-Wagner, Birgit; Thierfelder, Kolja M

    2016-11-01

    Endovascular therapy in addition to standard care (EVT+SC) has been demonstrated to be more effective than SC in acute ischemic large vessel occlusion stroke. Our aim was to determine the cost-effectiveness of EVT+SC depending on patients' initial National Institutes of Health Stroke Scale (NIHSS) score, time from symptom onset, Alberta Stroke Program Early CT Score (ASPECTS), and occlusion location. A decision model based on Markov simulations estimated lifetime costs and quality-adjusted life years (QALYs) associated with both strategies applied in a US setting. Model input parameters were obtained from the literature, including recently pooled outcome data of 5 randomized controlled trials (ESCAPE [Endovascular Treatment for Small Core and Proximal Occlusion Ischemic Stroke], EXTEND-IA [Extending the Time for Thrombolysis in Emergency Neurological Deficits-Intra-Arterial], MR CLEAN [Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands], REVASCAT [Randomized Trial of Revascularization With Solitaire FR Device Versus Best Medical Therapy in the Treatment of Acute Stroke Due to Anterior Circulation Large Vessel Occlusion Presenting Within 8 Hours of Symptom Onset], and SWIFT PRIME [Solitaire With the Intention for Thrombectomy as Primary Endovascular Treatment]). Probabilistic sensitivity analysis was performed to estimate uncertainty of the model results. Net monetary benefits, incremental costs, incremental effectiveness, and incremental cost-effectiveness ratios were derived from the probabilistic sensitivity analysis. The willingness-to-pay was set to $50 000/QALY. Overall, EVT+SC was cost-effective compared with SC (incremental cost: $4938, incremental effectiveness: 1.59 QALYs, and incremental cost-effectiveness ratio: $3110/QALY) in 100% of simulations. In all patient subgroups, EVT+SC led to gained QALYs (range: 0.47-2.12), and mean incremental cost-effectiveness ratios were considered cost-effective. However, subgroups with ASPECTS ≤5 or with M2 occlusions showed considerably higher incremental cost-effectiveness ratios ($14 273/QALY and $28 812/QALY, respectively) and only reached suboptimal acceptability in the probabilistic sensitivity analysis (75.5% and 59.4%, respectively). All other subgroups had acceptability rates of 90% to 100%. EVT+SC is cost-effective in most subgroups. In patients with ASPECTS ≤5 or with M2 occlusions, cost-effectiveness remains uncertain based on current data. © 2016 American Heart Association, Inc.

  5. A literature review to evaluate the economic value of ranolazine for the symptomatic treatment of chronic angina pectoris.

    PubMed

    Vellopoulou, Katerina; Kourlaba, Georgia; Maniadakis, Nikos; Vardas, Panagiotis

    2016-05-15

    To conduct a systematic review of the evidence regarding the economic value of ranolazine relative to standard-of-care (SOC) for the treatment of symptomatic chronic stable angina (CSA). Electronic databases were searched using relevant keywords. The identified studies were independently reviewed by two investigators against pre-determined inclusion and exclusion criteria. Their data were extracted using a relevant form and consequently were synthesized. Studies were also evaluated using the Quality of Health Economic Studies scale. The main outcomes considered were the cost and effectiveness for each comparator and the incremental cost per quality-adjusted-life year (QALY) gained. Six studies were included in the review. Five of these assessed the cost-utility of ranolazine added to SOC, compared to SOC alone, using decision trees or Markov models whereas one was a retrospective cost evaluation study. The analysis was conducted from a payer perspective in five studies and from a societal perspective in one study with the time horizon varying between six months and a year. The incremental cost-effectiveness ratio (ICER), ranged from €4000 to €15,000 per QALY gained. Ranolazine appears to be dominant or cost-effective, mainly due to its ability to decrease angina-related hospitalizations and also due to a marginal improvement in quality of life. The acquisition cost of ranolazine was the variable with the greatest impact upon the ICER. The existing evidence, although limited, indicates that ranolazine may be a dominant or cost-effective therapy option, for the treatment of patients with symptomatic CSA. Further research is required to evaluate the cost-effectiveness of ranolazine. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  6. Nasal Sculpting: Calculated and Predictable Tip Elevation With Cephalic Trim

    PubMed Central

    Redstone, Jeremiah S.; Nguyen, Jonathan; North, Durham Alan; Hazani, Ron; Drury, Brad; Yoder, Eric M.; Cooperman, Ross D.; Yoder, Virginia; Little, Jarrod A.; Florman, Larry D.; Wilhelmi, Bradon J.

    2015-01-01

    Background: Rhinoplasty techniques to affect nasal tip rotation are well described. Cephalic alar trim is a powerful method for achieving tip elevation. Previous studies and texts provide aesthetic guidelines for nasolabial angles. Often, surgeon experience determines the degree of lower lateral cartilage resection to achieve optimal results. This study analyzes the change in tip elevation with measured resections of the lower lateral cartilages. This can aid the surgeon in accurately predicting the effect of cephalic alar trim on tip elevation. Methods: Ten fresh cadaveric dissections were performed to determine the change in nasolabial angles after cephalic trim of the lower lateral cartilage. Closed rhinoplasty technique was performed using marginal and intercartilaginous incisions to expose the lower lateral cartilage. Caliper measurements of the lower lateral cartilage were recorded. Serial cephalic trim was performed in 25% increments. True lateral photographs were obtained before and after each serial excision. Nasolabial angle measurements were obtained using a digital goniometer for digital photo analysis. Results: Four female and 6 male cadavers were evaluated. The mean initial nasolabial angle was 106° ± 2°. The mean lower lateral cartilage width was 9.45 ± 1.38 mm. Serial 25% reductions in lower lateral cartilage height resulted in a mean total nasolabial angle change of 7.4°, 12.9°, and 19.6°, respectively. The mean incremental change in the nasolabial angle was 6.47° ± 1.25°. Conclusion: The nasolabial angle is an essential aesthetic feature. Cephalic trim is a key maneuver in affecting the nasolabial angle. A 25% lower lateral cartilage cephalic trim correlates with an average change in the nasolabial angle of 6.47°. Knowledge of the cephalic trim to nasolabial angle relationship aids in achieving desired tip elevation. PMID:26171091

  7. Computerized margin and texture analyses for differentiating bacterial pneumonia and invasive mucinous adenocarcinoma presenting as consolidation.

    PubMed

    Koo, Hyun Jung; Kim, Mi Young; Koo, Ja Hwan; Sung, Yu Sub; Jung, Jiwon; Kim, Sung-Han; Choi, Chang-Min; Kim, Hwa Jung

    2017-01-01

    Radiologists have used margin characteristics based on routine visual analysis; however, the attenuation changes at the margin of the lesion on CT images have not been quantitatively assessed. We established a CT-based margin analysis method by comparing a target lesion with normal lung attenuation, drawing a slope to represent the attenuation changes. This approach was applied to patients with invasive mucinous adenocarcinoma (n = 40) or bacterial pneumonia (n = 30). Correlations among multiple regions of interest (ROIs) were obtained using intraclass correlation coefficient (ICC) values. CT visual assessment, margin and texture parameters were compared for differentiating the two disease entities. The attenuation and margin parameters in multiple ROIs showed excellent ICC values. Attenuation slopes obtained at the margins revealed a difference between invasive mucinous adenocarcinoma and pneumonia (P<0.001), and mucinous adenocarcinoma produced a sharply declining attenuation slope. On multivariable logistic regression analysis, pneumonia had an ill-defined margin (odds ratio (OR), 4.84; 95% confidence interval (CI), 1.26-18.52; P = 0.02), ground-glass opacity (OR, 8.55; 95% CI, 2.09-34.95; P = 0.003), and gradually declining attenuation at the margin (OR, 12.63; 95% CI, 2.77-57.51, P = 0.001). CT-based margin analysis method has a potential to act as an imaging parameter for differentiating invasive mucinous adenocarcinoma and bacterial pneumonia.

  8. 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.

  9. 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.

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

    Yang, Rui; Zhang, Yingchen

    Designing market mechanisms for electricity distribution systems has been a hot topic due to the increased presence of smart loads and distributed energy resources (DERs) in distribution systems. The distribution locational marginal pricing (DLMP) methodology is one of the real-time pricing methods to enable such market mechanisms and provide economic incentives to active market participants. Determining the DLMP is challenging due to high power losses, the voltage volatility, and the phase imbalance in distribution systems. Existing DC Optimal Power Flow (OPF) approaches are unable to model power losses and the reactive power, while single-phase AC OPF methods cannot capture themore » phase imbalance. To address these challenges, in this paper, a three-phase AC OPF based approach is developed to define and calculate DLMP accurately. The DLMP is modeled as the marginal cost to serve an incremental unit of demand at a specific phase at a certain bus, and is calculated using the Lagrange multipliers in the three-phase AC OPF formulation. Extensive case studies have been conducted to understand the impact of system losses and the phase imbalance on DLMPs as well as the potential benefits of flexible resources.« less

  11. 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.

  12. Insights into the origins of drumbeat earthquakes, periodic low frequency seismicity, and plug degradation from multi-instrument monitoring at Tungurahua volcano, Ecuador, April 2015

    NASA Astrophysics Data System (ADS)

    Bell, Andrew; Hernandez, Stephen; Gaunt, Elizabeth; Mothes, Patricia; Hidalgo, Silvana; Ruiz, Mario

    2016-04-01

    Highly-periodic repeating 'drumbeat' earthquakes have been reported from several andesitic and dacitic volcanoes. Physical models for the origin of drumbeat earthquakes incorporate, to different extents, the incremental upward movement of viscous magma. However, the roles played by stick-slip friction, brittle failure, and fluid flow, and the relations between drumbeat earthquakes and other low-frequency seismic signals, remain controversial. Here we report the results of analysis of three weeks of geophysical data recorded during an unrest episode at Tungurahua, an andesitic stratovolcano in Ecuador, during April 2015, by the monitoring network of the Instituto Geofisico of Ecuador. Combined seismic, geodetic, infrasound, and gas monitoring has provided new insights into the origins of periodic low-frequency seismic signals, conduit processes, and the nature of current unrest. Over the three-week period, the relative seismic amplitude (RSAM) correlated closely with short-term deformation rates and gas fluxes. However, the characteristics of the seismic signals, as recorded at a short-period station closest to the summit crater, changed considerably with time. Initially high RSAM and gas fluxes, with modest ash emissions, were associated with continuous and 'pulsed' tremor signals (amplitude modulated, with 30-100 second periods). As activity levels decreased over several days, tremor episodes became increasingly intermittent, and short-lived bursts of low-frequency earthquakes with quasiperiodic inter-event times were observed. Following one day of quiescence, the onset of pronounced low frequency drumbeat earthquakes signalled the resumption of elevated unrest, initially with mean inter-event times of 32 seconds, and later increasing to 74 seconds and longer, with periodicity progressively breaking down over several days. A reduction in RSAM was then followed by one week of persistent, quasiperiodic, longer-duration emergent low-frequency pulses, including 'double events'. The unrest finished with a series of minor explosions and ash emissions, and a reduction in RSAM. None of the seismic events were associated with significant infrasound or ground-coupled acoustic waves. The persistent and steadily evolving periodicity of seismic signals, and contemporaneous inflation-deflation tilt cycle, suggest that incremental upward movement of a viscous magma plug determines the system periodicity, likely controlled by the balance between magma ascent rate, magma compressibility beneath the plug, and resisting forces at the plug margin. However, relations between a range of observations, including waveform similarity, periodicity, and amplitudes of contemporaneous discrete and continuous signals, suggest that the detected seismic signals are predominantly generated by gas flow that is largely decoupled from the magma ascent rate. Signals are generated by both continuous flow through longer-lived pathways, and by gas pulses passing through transient pathways generated by slip at the plug margins. The nature and amplitude of signals is therefore a product of the rate of gas flux and the evolving state of the degassing pathway, controlled in part by degradation and healing of the plug margins.

  13. Developing a stability assessment method for power electronics-based microgrids

    NASA Astrophysics Data System (ADS)

    Austin, Peter M.

    Modern microgrids with microsources and energy storage are dependent on power electronics for control and regulation. Under certain circumstances power electronics can be destabilizing to the system due to an effect called negative incremental impedance. A careful review of the theory and literature on the subject is presented. This includes stability criteria for both AC and DC systems, as well as a discussion on the limitations posed by the analysis. A method to integrate stability assessment with higher-level microgrid architectural design is proposed. Crucial to this is impedance characterization of individual components, which was accomplished through simulation. DC and AC impedance measurement blocks were created in Matlab simulink to automate the process. A detailed switching-level model of a DC microgrid was implemented in simulink, including wind turbine microsource, battery storage, and three phase inverter. Maximum power point tracking (MPPT) was included to maximize the efficiency of the turbine and was implemented through three rectifier alternatives and control schemes. The stability characteristics of each was compared in the final analysis. Impedance data was collected individually from the components and used to assess stability in the system as a whole. The results included the assessment of stability, margin, and unstable operating points to demonstrate the feasibility of the proposed approach.

  14. Close Margins Less Than 2 mm Are Not Associated With Higher Risks of 10-Year Local Recurrence and Breast Cancer Mortality Compared With Negative Margins in Women Treated With Breast-Conserving Therapy.

    PubMed

    Tyler, Susan; Truong, Pauline T; Lesperance, Mary; Nichol, Alan; Baliski, Chris; Warburton, Rebecca; Tyldesley, Scott

    2018-03-13

    The 2014 Society of Surgical Oncology-American Society for Radiation Oncology consensus suggested "no ink on tumor" is a sufficient surgical margin for invasive breast cancer treated with breast-conserving surgery (BCS). Whether close margins <2 mm are associated with inferior outcomes remains controversial. This study evaluated 10-year outcomes by margin status in a population-based cohort treated with BCS and adjuvant radiation therapy (RT). The subjects were 10,863 women with invasive cancer categorized as pT1 to T3, any N, and M0 referred from 2001 to 2011, an era in which the institutional policy was to re-excise close or positive margins, except in select cases. All women underwent BCS and whole-breast RT with or without boost RT. Local recurrence (LR) and breast cancer-specific survival (BCSS) were examined using competing-risk analysis in cohorts with negative (≥2 mm; n = 9241, 85%), close (<2 mm; n = 1310, 12%), or positive (tumor touching ink; n = 312, 3%) margins. Multivariable analysis and matched-pair analysis were performed. The median follow-up period was 8 years. Systemic therapy was used in 87% of patients. Boost RT was used in 34.1%, 76.9%, and 79.5% of patients with negative, close, and positive margins, respectively. In the negative, close, and positive margin cohorts, the 10-year cumulative incidence of LR was 1.8%, 2.0%, and 1.1%, respectively (P = .759). Corresponding BCSS estimates were 93.9%, 91.8%, and 87.9%, respectively (P < .001). On multivariable analysis, close margins were not associated with increased LR (hazard ratio, 1.25; 95% confidence interval 0.79-1.97; P = .350) or reduced BCSS (hazard ratio, 1.25; 95% confidence interval 0.98-1.58, P = .071) relative to negative margins. On matched-pair analysis, close margin cases had similar LR (P = .114) and BCSS (P = .100) to negative margin controls. Select cases with close or positive margins in this population-based analysis had similar LR and BCSS to cases with negative margins. While these findings do not endorse omitting re-excision for all cases, the data support a policy of accepting carefully selected cases with close margins for adjuvant RT without re-excision. Copyright © 2018 Elsevier Inc. All rights reserved.

  15. The Prognostic Value of Varying Definitions of Positive Resection Margin in Patients with Colorectal Cancer Liver Metastases.

    PubMed

    Wang, Jane; Margonis, Georgios Antonios; Amini, Neda; Andreatos, Nikolaos; Yuan, Chunhui; Damaskos, Christos; Antoniou, Efstathios; Garmpis, Nikolaos; Buettner, Stefan; Barbon, Carlotta; Deshwar, Amar; He, Jin; Burkhart, Richard; Pawlik, Timothy M; Wolfgang, Christopher L; Weiss, Matthew J

    2018-04-09

    Varying definitions of resection margin clearance are currently employed among patients with colorectal cancer liver metastases (CRLM). Specifically, a microscopically positive margin (R1) has alternatively been equated with an involved margin (margin width = 0 mm) or a margin width < 1 mm. Consequently, patients with a margin width of 0-1 mm (sub-mm) are inconsistently classified in either the R0 or R1 categories, thus obscuring the prognostic implications of sub-mm margins. Six hundred thirty-three patients who underwent resection of CRLM were identified. Both R1 definitions were alternatively employed and multivariable analysis was used to determine the predictive power of each definition, as well as the prognostic implications of a sub-mm margin. Five hundred thirty-nine (85.2%) patients had a margin width ≥ 1 mm, 42 had a sub-mm margin width, and 52 had an involved margin (0 mm). A margin width ≥ 1 mm was associated with improved survival vs. a sub-mm margin (65 vs. 36 months; P = 0.03) or an involved margin (65 vs. 33 months; P < 0.001). No significant difference in survival was detected between patients with involved vs. sub-mm margins (P = 0.31). A sub-mm margin and an involved margin were both independent predictors of worse OS (HR 1.66, 1.04-2.67; P = 0.04, and HR 2.14, 1.46-3.16; P < 0.001, respectively) in multivariable analysis. Importantly, after combining the two definitions, patients with either an involved margin or a sub-mm margin were associated with worse OS in multivariable analysis (HR 1.94, 1.41-2.65; P < 0.001). Patients with involved or sub-mm margins demonstrated a similar inferior OS vs. patients with a margin width > 1 mm. Consequently, a uniform definition of R1 as a margin width < 1 mm should perhaps be employed by future studies.

  16. Wind resource quality affected by high levels of renewables

    DOE PAGES

    Diakov, Victor

    2015-06-17

    For solar photovoltaic (PV) and wind resources, the capacity factor is an important parameter describing the quality of the resource. As the share of variable renewable resources (such as PV and wind) on the electric system is increasing, so does curtailment (and the fraction of time when it cannot be avoided). At high levels of renewable generation, curtailments effectively change the practical measure of resource quality from capacity factor to the incremental capacity factor. The latter accounts only for generation during hours of no curtailment and is directly connected with the marginal capital cost of renewable generators for a givenmore » level of renewable generation during the year. The Western U.S. wind generation is analyzed hourly for a system with 75% of annual generation from wind, and it is found that the value for the system of resources with equal capacity factors can vary by a factor of 2, which highlights the importance of using the incremental capacity factor instead. Finally, the effect is expected to be more pronounced in smaller geographic areas (or when transmission limitations imposed) and less pronounced at lower levels of renewable energy in the system with less curtailment.« less

  17. Cost-effectiveness of quantitative fecal lactoferrin assay for diagnosis of symptomatic patients with ileal pouch-anal anastomosis.

    PubMed

    Parsi, Mansour A; Ellis, Jeffrey J; Lashner, Bret A

    2008-08-01

    To assess cost-effectiveness of fecal lactoferrin (FL) as the initial diagnostic approach to symptomatic patients with ileal pouch-anal anastomosis (IPAA). Four competing strategies [empiric metronidazole therapy (txMTZ), initial pouch endoscopy with biopsy (testBiop), initial FL assay followed by metronidazole therapy (testFL+MTZ), and initial FL assay followed by pouch endoscopy and biopsy (testFL+Biop)] were modeled in a decision tree. In the base-case, the average cost per patient was $241 for testFL+MTZ, $251 for txMTZ, $405 for testFL+Biop, and $431 for testBiop. The testBiop strategy had greater effectiveness compared with txMTZ but at an incremental cost of $158 per day. The txMTZ strategy was slightly more costly and minimally more effective than testFL+MTZ with an incremental cost effectiveness of just over $12 per day. However, the testFL+MTZ strategy was associated with a 31% absolute reduction in antibiotic exposure compared with the txMTZ strategy. Compared with empiric metronidazole therapy, FL before treatment with metronidazole is less costly with less exposure to antibiotics and less need for endoscopy, with only marginal decrease in effectiveness.

  18. The SIMS trial: adjustable anchored single-incision mini-slings versus standard tension-free midurethral slings in the surgical management of female stress urinary incontinence. A study protocol for a pragmatic, multicentre, non-inferiority randomised controlled trial.

    PubMed

    Abdel-Fattah, Mohamed; MacLennan, Graeme; Kilonzo, Mary; Assassa, R Phil; McCormick, Kirsty; Davidson, Tracey; McDonald, Alison; N'Dow, James; Wardle, Judith; Norrie, John

    2017-08-11

    Single-incision mini-slings (SIMS) represent the third generation of midurethral slings. They have been developed with the aim of offering a true ambulatory procedure for treatment of female stress urinary incontinence (SUI) with reduced morbidity and earlier recovery while maintaining similar efficacy to standard midurethral slings (SMUS). The aim of this study is to determine the clinical and cost-effectiveness of adjustable anchored SIMS compared with tension-free SMUS in the surgical management of female SUI, with 3-year follow-up. A pragmatic, multicentre, non-inferiority randomised controlled trial. The primary outcome measure is the patient-reported success rate measured by the Patient Global Impression of Improvement at 12 months. The primary economic outcome will be incremental cost per quality-adjusted life year gained at 12 months. The secondary outcomes measures include adverse events, objective success rates, impact on other lower urinary tract symptoms, health-related quality of life profile and sexual function, and reoperation rates for SUI. Secondary economic outcomes include National Health Service and patient primary and secondary care resource use and costs, incremental cost-effectiveness and incremental net benefit. The statistical analysis of the primary outcome will be by intention-to-treat and also a per-protocol analysis. Results will be displayed as estimates and 95% CIs. CIs around observed differences will then be compared with the prespecified non-inferiority margin. Secondary outcomes will be analysed similarly. The North of Scotland Research Ethics Committee has approved this study (13/NS/0143). The dissemination plans include HTA monograph, presentation at international scientific meetings and publications in high-impact, open-access journals. The results will be included in the updates of the National Institute for Health and Care Excellence and the European Association of Urology guidelines; these two specific guidelines directly influence practice in the UK and worldwide specialists, respectively. In addition, plain English-language summary of the main findings/results will be presented for relevant patient organisations. ISRCTN93264234. The SIMS study is currently recruiting in 20 UK research centres. The first patient was randomised on 4 February 2014, with follow-up to be completed at the end of February 2020. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

  19. A passive gust alleviation system for a light aircraft

    NASA Technical Reports Server (NTRS)

    Roesch, P.; Harlan, R. B.

    1975-01-01

    A passive aeromechanical gust alleviation system was examined for application to a Cessna 172. The system employs small auxiliary wings to sense changes in angle of attack and to drive the wing flaps to compensate the resulting incremental lift. The flaps also can be spring loaded to neutralize the effects of variations in dynamic pressure. Conditions for gust alleviation are developed and shown to introduce marginal stability if both vertical and horizontal gusts are compensated. Satisfactory behavior is realized if only vertical gusts are absorbed; however, elevator control is effectively negated by the system. Techniques to couple the elevator and flaps are demonstrated to restore full controllability without sacrifice of gust alleviation.

  20. Abutment Disconnection/Reconnection Affects Peri-implant Marginal Bone Levels: A Meta-Analysis.

    PubMed

    Koutouzis, Theofilos; Gholami, Fatemeh; Reynolds, John; Lundgren, Tord; Kotsakis, Georgios A

    Preclinical and clinical studies have shown that marginal bone loss can be secondary to repeated disconnection and reconnection of abutments that affect the peri-implant mucosal seal. The aim of this systematic review and meta-analysis was to evaluate the impact of abutment disconnections/reconnections on peri-implant marginal bone level changes. To address this question, two reviewers independently performed an electronic search of three major databases up to October 2015 complemented by manual searches. Eligible articles were selected on the basis of prespecified inclusion and exclusion criteria after a two-phase search strategy and assessed for risk of bias. A random-effects meta-analysis was performed for marginal bone loss. The authors initially identified 392 titles and abstracts. After evaluation, seven controlled clinical studies were included. Qualitative assessment of the articles revealed a trend toward protective marginal bone level preservation for implants with final abutment placement (FAP) at the time of implant placement compared with implants for which there were multiple abutment placements (MAP). The FAP group exhibited a marginal bone level change ranging from 0.08 to 0.34 mm, whereas the MAP group exhibited a marginal bone level change ranging from 0.09 to 0.55 mm. Meta-analysis of the seven studies reporting on 396 implants showed significantly greater bone loss in cases of multiple abutment disconnections/reconnections. The weighted mean difference in marginal bone loss was 0.19 mm (95% confidence interval, 0.06-0.32 mm), favoring bone preservation in the FAP group. Within the limitations of this meta-analysis, abutment disconnection and reconnection significantly affected peri-implant marginal bone levels. These findings pave the way for revisiting current restorative protocols at the restorative treatment planning stage to prevent incipient marginal bone loss.

  1. Incremental heating of Bishop Tuff sanidine reveals preeruptive radiogenic Ar and rapid remobilization from cold storage

    NASA Astrophysics Data System (ADS)

    Andersen, Nathan L.; Jicha, Brian R.; Singer, Brad S.; Hildreth, Wes

    2017-11-01

    Accurate and precise ages of large silicic eruptions are critical to calibrating the geologic timescale and gauging the tempo of changes in climate, biologic evolution, and magmatic processes throughout Earth history. The conventional approach to dating these eruptive products using the 40Ar/39Ar method is to fuse dozens of individual feldspar crystals. However, dispersion of fusion dates is common and interpretation is complicated by increasingly precise data obtained via multicollector mass spectrometry. Incremental heating of 49 individual Bishop Tuff (BT) sanidine crystals produces 40Ar/39Ar dates with reduced dispersion, yet we find a 16-ky range of plateau dates that is not attributable to excess Ar. We interpret this dispersion to reflect cooling of the magma reservoir margins below ˜475 °C, accumulation of radiogenic Ar, and rapid preeruption remobilization. Accordingly, these data elucidate the recycling of subsolidus material into voluminous rhyolite magma reservoirs and the effect of preeruptive magmatic processes on the 40Ar/39Ar system. The youngest sanidine dates, likely the most representative of the BT eruption age, yield a weighted mean of 764.8 ± 0.3/0.6 ka (2σ analytical/full uncertainty) indicating eruption only ˜7 ky following the Matuyama‑Brunhes magnetic polarity reversal. Single-crystal incremental heating provides leverage with which to interpret complex populations of 40Ar/39Ar sanidine and U-Pb zircon dates and a substantially improved capability to resolve the timing and causal relationship of events in the geologic record.

  2. Incremental heating of Bishop Tuff sanidine reveals preeruptive radiogenic Ar and rapid remobilization from cold storage.

    PubMed

    Andersen, Nathan L; Jicha, Brian R; Singer, Brad S; Hildreth, Wes

    2017-11-21

    Accurate and precise ages of large silicic eruptions are critical to calibrating the geologic timescale and gauging the tempo of changes in climate, biologic evolution, and magmatic processes throughout Earth history. The conventional approach to dating these eruptive products using the 40 Ar/ 39 Ar method is to fuse dozens of individual feldspar crystals. However, dispersion of fusion dates is common and interpretation is complicated by increasingly precise data obtained via multicollector mass spectrometry. Incremental heating of 49 individual Bishop Tuff (BT) sanidine crystals produces 40 Ar/ 39 Ar dates with reduced dispersion, yet we find a 16-ky range of plateau dates that is not attributable to excess Ar. We interpret this dispersion to reflect cooling of the magma reservoir margins below ∼475 °C, accumulation of radiogenic Ar, and rapid preeruption remobilization. Accordingly, these data elucidate the recycling of subsolidus material into voluminous rhyolite magma reservoirs and the effect of preeruptive magmatic processes on the 40 Ar/ 39 Ar system. The youngest sanidine dates, likely the most representative of the BT eruption age, yield a weighted mean of 764.8 ± 0.3/0.6 ka (2σ analytical/full uncertainty) indicating eruption only ∼7 ky following the Matuyama-Brunhes magnetic polarity reversal. Single-crystal incremental heating provides leverage with which to interpret complex populations of 40 Ar/ 39 Ar sanidine and U-Pb zircon dates and a substantially improved capability to resolve the timing and causal relationship of events in the geologic record.

  3. [Planning of esthetic oral rehabilitation according to correlative analysis of clinical and morphological features of the marginal gingiva].

    PubMed

    Stafeev, A A; Zinov'ev, G I; Drozdov, D D

    2015-01-01

    The orthopedic restoration and related to its clinical stages (preparation, gingival retraction, impression) is often associated with complications which arise from the marginal gingiva. The technology of indirect ceramic restoration requires an assessment of the clinical and morphological parameters of periodontal tissues. The study outlines correlation between the type of periodontal histhology and inflammatory and degenerative complications that has been established after the analysis of morphofunctional state of periodontal tissue. Results of clinical studies and correlation analysis of clinical and morphological parameters of marginal gingiva has shown that important parameter influencing the choice of manufacturing technology are the position of restoration margin relatively to marginal gingiva and periodontal morphotype.

  4. Retroactive Operations: On "Increments" in Mandarin Chinese Conversations

    ERIC Educational Resources Information Center

    Lim, Ni Eng

    2014-01-01

    Conversation Analysis (CA) has established repair (Schegloff, Jefferson & Sacks 1977; Schegloff 1979; Kitzinger 2013) as a conversational mechanism for managing contingencies of talk-in-interaction. In this dissertation, I look at a particular sort of "repair" termed TCU-continuations (or otherwise known increments in other…

  5. Aerodynamic Analyses and Database Development for Ares I Vehicle First Stage Separation

    NASA Technical Reports Server (NTRS)

    Pamadi, Bandu N.; Pei, Jing; Pinier, Jeremy T.; Holland, Scott D.; Covell, Peter F.; Klopfer, Goetz, H.

    2012-01-01

    This paper presents the aerodynamic analysis and database development for the first stage separation of the Ares I A106 Crew Launch Vehicle configuration. Separate databases were created for the first stage and upper stage. Each database consists of three components: isolated or free-stream coefficients, power-off proximity increments, and power-on proximity increments. The power-on database consists of three parts, all plumes firing at nominal conditions, the one booster deceleration motor out condition, and the one ullage settling motor out condition. The isolated and power-off incremental databases were developed using wind tunnel test data. The power-on proximity increments were developed using CFD solutions.

  6. Economic Implications of Widespread Expansion of Frozen Section Margin Analysis to Guide Surgical Resection in Women With Breast Cancer Undergoing Breast-Conserving Surgery.

    PubMed

    Boughey, Judy C; Keeney, Gary L; Radensky, Paul; Song, Christine P; Habermann, Elizabeth B

    2016-04-01

    In the current health care environment, cost effectiveness is critically important in policy setting and care of patients. This study performed a health economic analysis to assess the implications to providers and payers of expanding the use of frozen section margin analysis to minimize reoperations for patients undergoing breast cancer lumpectomy. A health care economic impact model was built to assess annual costs associated with breast lumpectomy procedures with and without frozen section margin analysis to avoid reoperation. If frozen section margin analysis is used in 20% of breast lumpectomies and under a baseline assumption that 35% of initial lumpectomies without frozen section analysis result in reoperations, the potential annual cost savings are $18.2 million to payers and $0.4 million to providers. Under the same baseline assumption, if 100% of all health care facilities adopted the use of frozen section margin analysis for breast lumpectomy procedures, the potential annual cost savings are $90.9 million to payers and $1.8 million to providers. On the basis of 10,000 simulations, use of intraoperative frozen section margin analysis yields cost saving for payers and is cost neutral to slightly cost saving for providers. This economic analysis indicates that widespread use of frozen section margin evaluation intraoperatively to guide surgical resection in breast lumpectomy cases and minimize reoperations would be beneficial to cost savings not only for the patient but also for payers and, in most cases, for providers. Copyright © 2016 by American Society of Clinical Oncology.

  7. Polymerization shrinkage stresses in different restorative techniques for non-carious cervical lesions.

    PubMed

    de Oliveira Correia, Ayla Macyelle; Tribst, João Paulo Mendes; de Souza Matos, Felipe; Platt, Jeffrey A; Caneppele, Taciana Marco Ferraz; Borges, Alexandre Luiz Souto

    2018-06-20

    This study evaluated the effect of different restorative techniques for non-carious cervical lesions (NCCL) on polymerization shrinkage stress of resins using three-dimensional (3D) finite element analysis (FEA). 3D-models of a maxillary premolar with a NCCL restored with different filling techniques (bulk filling and incremental) were generated to be compared by nonlinear FEA. The bulk filling technique was used for groups B (NCCL restored with Filtek™ Bulk Fill) and C (Filtek™ Z350 XT). The incremental technique was subdivided according to mode of application: P (2 parallel increments of the Filtek™ Z350 XT), OI (2 oblique increments of the Filtek™ Z350 XT, with incisal first), OIV (2 oblique increments of the Filtek™ Z350 XT, with incisal first and increments with the same volume), OG (2 oblique increments of the Filtek™ Z350 XT, with gingival first) and OGV (2 oblique increments of the Filtek™ Z350 XT, with gingival first and increments with the same volume), resulting in 7 models. All materials were considered isotropic, elastic and linear. The results were expressed in maximum principal stress (MPS). The tension stress distribution was influenced by the restorative technique. The lowest stress concentration occurred in group B followed by OG, OGV, OI, OIV, P and C; the incisal interface was more affected than the gingival. The restoration of NCCLs with bulk fill composite resulted in lower shrinkage stress in the gingival and incisal areas, followed by incremental techniques with the initial increment placed on the gingival wall. The non-carious cervical lesions (NCCLs) restored with bulk fill composite have a more favorable biomechanical behavior. Copyright © 2018. Published by Elsevier Ltd.

  8. A method for identifying EMI critical circuits during development of a large C3

    NASA Astrophysics Data System (ADS)

    Barr, Douglas H.

    The circuit analysis methods and process Boeing Aerospace used on a large, ground-based military command, control, and communications (C3) system are described. This analysis was designed to help identify electromagnetic interference (EMI) critical circuits. The methodology used the MIL-E-6051 equipment criticality categories as the basis for defining critical circuits, relational database technology to help sort through and account for all of the approximately 5000 system signal cables, and Macintosh Plus personal computers to predict critical circuits based on safety margin analysis. The EMI circuit analysis process systematically examined all system circuits to identify which ones were likely to be EMI critical. The process used two separate, sequential safety margin analyses to identify critical circuits (conservative safety margin analysis, and detailed safety margin analysis). These analyses used field-to-wire and wire-to-wire coupling models using both worst-case and detailed circuit parameters (physical and electrical) to predict circuit safety margins. This process identified the predicted critical circuits that could then be verified by test.

  9. Cost-effectiveness analysis of germ-line BRCA testing in women with breast cancer and cascade testing in family members of mutation carriers.

    PubMed

    Tuffaha, Haitham W; Mitchell, Andrew; Ward, Robyn L; Connelly, Luke; Butler, James R G; Norris, Sarah; Scuffham, Paul A

    2018-01-04

    PurposeTo evaluate the cost-effectiveness of BRCA testing in women with breast cancer, and cascade testing in family members of BRCA mutation carriers.MethodsA cost-effectiveness analysis was conducted using a cohort Markov model from a health-payer perspective. The model estimated the long-term benefits and costs of testing women with breast cancer who had at least a 10% pretest BRCA mutation probability, and the cascade testing of first- and second-degree relatives of women who test positive.ResultsCompared with no testing, BRCA testing of affected women resulted in an incremental cost per quality-adjusted life-year (QALY) gained of AU$18,900 (incremental cost AU$1,880; incremental QALY gain 0.10) with reductions of 0.04 breast and 0.01 ovarian cancer events. Testing affected women and cascade testing of family members resulted in an incremental cost per QALY gained of AU$9,500 compared with testing affected women only (incremental cost AU$665; incremental QALY gain 0.07) with additional reductions of 0.06 breast and 0.01 ovarian cancer events.ConclusionBRCA testing in women with breast cancer is cost-effective and is associated with reduced risk of cancer and improved survival. Extending testing to cover family members of affected women who test positive improves cost-effectiveness beyond restricting testing to affected women only.GENETICS in MEDICINE advance online publication, 4 January 2018; doi:10.1038/gim.2017.231.

  10. Analysis of Trajectory Parameters for Probe and Round-Trip Missions to Venus

    NASA Technical Reports Server (NTRS)

    Dugan, James F., Jr.; Simsic, Carl R.

    1960-01-01

    For one-way transfers between Earth and Venus, charts are obtained that show velocity, time, and angle parameters as functions of the eccentricity and semilatus rectum of the Sun-focused vehicle conic. From these curves, others are obtained that are useful in planning one-way and round-trip missions to Venus. The analysis is characterized by circular coplanar planetary orbits, successive two-body approximations, impulsive velocity changes, and circular parking orbits at 1.1 planet radii. For round trips the mission time considered ranges from 65 to 788 days, while wait time spent in the parking orbit at Venus ranges from 0 to 467 days. Individual velocity increments, one-way travel times, and departure dates are presented for round trips requiring the minimum total velocity increment. For both single-pass and orbiting Venusian probes, the time span available for launch becomes appreciable with only a small increase in velocity-increment capability above the minimum requirement. Velocity-increment increases are much more effective in reducing travel time for single-pass probes than they are for orbiting probes. Round trips composed of a direct route along an ellipse tangent to Earth's orbit and an aphelion route result in the minimum total velocity increment for wait times less than 100 days and mission times ranging from 145 to 612 days. Minimum-total-velocity-increment trips may be taken along perihelion-perihelion routes for wait times ranging from 300 to 467 days. These wait times occur during missions lasting from 640 to 759 days.

  11. Toward disentangling the effect of hydrologic and nitrogen source changes from 1992 to 2001 on incremental nitrogen yield in the contiguous United States

    NASA Astrophysics Data System (ADS)

    Alam, Md Jahangir; Goodall, Jonathan L.

    2012-04-01

    The goal of this research was to quantify the relative impact of hydrologic and nitrogen source changes on incremental nitrogen yield in the contiguous United States. Using nitrogen source estimates from various federal data bases, remotely sensed land use data from the National Land Cover Data program, and observed instream loadings from the United States Geological Survey National Stream Quality Accounting Network program, we calibrated and applied the spatially referenced regression model SPARROW to estimate incremental nitrogen yield for the contiguous United States. We ran different model scenarios to separate the effects of changes in source contributions from hydrologic changes for the years 1992 and 2001, assuming that only state conditions changed and that model coefficients describing the stream water-quality response to changes in state conditions remained constant between 1992 and 2001. Model results show a decrease of 8.2% in the median incremental nitrogen yield over the period of analysis with the vast majority of this decrease due to changes in hydrologic conditions rather than decreases in nitrogen sources. For example, when we changed the 1992 version of the model to have nitrogen source data from 2001, the model results showed only a small increase in median incremental nitrogen yield (0.12%). However, when we changed the 1992 version of the model to have hydrologic conditions from 2001, model results showed a decrease of approximately 8.7% in median incremental nitrogen yield. We did, however, find notable differences in incremental yield estimates for different sources of nitrogen after controlling for hydrologic changes, particularly for population related sources. For example, the median incremental yield for population related sources increased by 8.4% after controlling for hydrologic changes. This is in contrast to a 2.8% decrease in population related sources when hydrologic changes are included in the analysis. Likewise we found that median incremental yield from urban watersheds increased by 6.8% after controlling for hydrologic changes—in contrast to the median incremental nitrogen yield from cropland watersheds, which decreased by 2.1% over the same time period. These results suggest that, after accounting for hydrologic changes, population related sources became a more significant contributor of nitrogen yield to streams in the contiguous United States over the period of analysis. However, this study was not able to account for the influence of human management practices such as improvements in wastewater treatment plants or Best Management Practices that likely improved water quality, due to a lack of data for quantifying the impact of these practices for the study area.

  12. International Space Station Increment-4/5 Microgravity Environment Summary Report

    NASA Technical Reports Server (NTRS)

    Jules, Kenol; Hrovat, Kenneth; Kelly, Eric; McPherson, Kevin; Reckart, Timothy

    2003-01-01

    This summary report presents the results of some of the processed acceleration data measured aboard the International Space Station during the period of December 2001 to December 2002. Unlike the past two ISS Increment reports, which were increment specific, this summary report covers two increments: Increments 4 and 5, hereafter referred to as Increment-4/5. Two accelerometer systems were used to measure the acceleration levels for the activities that took place during Increment-4/5. Due to time constraint and lack of precise timeline information regarding some payload operations and station activities, not a11 of the activities were analyzed for this report. The National Aeronautics and Space Administration sponsors the Microgravity Acceleration Measurement System and the Space Acceleration Microgravity System to support microgravity science experiments which require microgravity acceleration measurements. On April 19, 2001, both the Microgravity Acceleration Measurement System and the Space Acceleration Measurement System units were launched on STS-100 from the Kennedy Space Center for installation on the International Space Station. The Microgravity Acceleration Measurement System supports science experiments requiring quasi-steady acceleration measurements, while the Space Acceleration Measurement System unit supports experiments requiring vibratory acceleration measurement. The International Space Station Increment-4/5 reduced gravity environment analysis presented in this report uses acceleration data collected by both sets of accelerometer systems: The Microgravity Acceleration Measurement System, which consists of two sensors: the low-frequency Orbital Acceleration Research Experiment Sensor Subsystem and the higher frequency High Resolution Accelerometer Package. The low frequency sensor measures up to 1 Hz, but is routinely trimmean filtered to yield much lower frequency acceleration data up to 0.01 Hz. This filtered data can be mapped to arbitrary locations for characterizing the quasi-steady environment for payloads and the vehicle. The high frequency sensor is used to characterize the vibratory environment up to 100 Hz at a single measurement location. The Space Acceleration Measurement System, which deploys high frequency sensors, measures vibratory acceleration data in the range of 0.01 to 400 Hz at multiple measurement locations. This summary report presents analysis of some selected quasi-steady and vibratory activities measured by these accelerometers during Increment- 4/5 from December 2001 to December 2002.

  13. The role of adjuvant treatment in early-stage oral cavity squamous cell carcinoma: An international collaborative study.

    PubMed

    Fridman, Eran; Na'ara, Shorook; Agarwal, Jaiprakash; Amit, Moran; Bachar, Gideon; Villaret, Andrea Bolzoni; Brandao, Jose; Cernea, Claudio R; Chaturvedi, Pankaj; Clark, Jonathan; Ebrahimi, Ardalan; Fliss, Dan M; Jonnalagadda, Sashikanth; Kohler, Hugo F; Kowalski, Luiz P; Kreppel, Matthias; Liao, Chun-Ta; Patel, Snehal G; Patel, Raj P; Robbins, K Thomas; Shah, Jatin P; Shpitzer, Thomas; Yen, Tzu-Chen; Zöller, Joachim E; Gil, Ziv

    2018-05-14

    Up to half of patients with oral cavity squamous cell carcinoma (OCSCC) have stage I to II disease. When adequate resection is attained, no further treatment is needed; however, re-resection or radiotherapy may be indicated for patients with positive or close margins. This multicenter study evaluated the outcomes and role of adjuvant treatment in patients with stage I to II OCSCC. Overall survival (OS), disease-specific survival, local-free survival, and disease-free survival rates were calculated with Kaplan-Meier analysis. Of 1257 patients with T1-2N0M0 disease, 33 (2.6%) had positive margins, and 205 (16.3%) had close margins. The 5-year OS rate was 80% for patients with clear margins, 52% for patients with close margins, and 63% for patients with positive margins (P < .0001). In a multivariate analysis, age, depth of invasion, and margins were independent predictors of outcome. Close margins were associated with a >2-fold increase in the risk of recurrence (P < .0001). The multivariate analysis revealed that adjuvant treatment significantly improved the outcomes of patients with close/positive margins (P = .002 to .03). Patients with stage I to II OCSCC and positive/close margins have poor long-term outcomes. For this population, adjuvant treatment may be associated with improved survival. Cancer 2018. © 2018 American Cancer Society. © 2018 American Cancer Society.

  14. 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 preliminary evidence of the positive clinical effect of multiparametric MR imaging-directed IFS analysis for patients who undergo prostatectomy. © RSNA, 2014.

  15. Equity and Entrepreneurialism: The Impact of Tax Increment Financing on School Finance.

    ERIC Educational Resources Information Center

    Weber, Rachel

    2003-01-01

    Describes tax increment financing (TIF), an entrepreneurial strategy with significant fiscal implications for overlapping taxing jurisdictions that provide these functions. Statistical analysis of TIF's impact on the finances of one Illinois county's school districts indicates that municipal use of TIF depletes the property tax revenues of schools…

  16. Changes in the Economic Value of Variable Generation at High Penetration Levels: A Pilot Case Study of California

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

    Mills, Andrew; Wiser, Ryan

    2012-05-18

    We estimate the long-run economic value of variable renewable generation with increasing penetration using a unique investment and dispatch model that captures long-run investment decisions while also incorporating detailed operational constraints and hourly time resolution over a full year. High time resolution and the incorporation of operational constraints are important for estimating the economic value of variable generation, as is the use of a modeling framework that accommodates new investment decisions. The model is herein applied with a case study that is loosely based on California in 2030. Increasing amounts of wind, photovoltaics (PV), and concentrating solar power (CSP) with and without thermal energy storage (TES) are added one at a time. The marginal economic value of these renewable energy sources is estimated and then decomposed into capacity value, energy value, day-ahead forecast error cost, and ancillary services. The marginal economic value, as defined here, is primarily based on the combination of avoided capital investment cost and avoided variable fuel and operations and maintenance costs from other power plants in the power system. Though the model only captures a subset of the benefits and costs of renewable energy, it nonetheless provides unique insights into how the value of that subset changes with technology and penetration level. Specifically, in this case study implementation of the model, the marginal economic value of all three solar options is found to exceed the value of a flat-block of power (as well as wind energy) by \\more » $$20--30/MWh at low penetration levels, largely due to the high capacity value of solar at low penetration. Because the value of CSP per unit of energy is found to be high with or without thermal energy storage at low penetration, we find little apparent incremental value to thermal storage at low solar penetration in the present case study analysis. The marginal economic value of PV and CSP without thermal storage is found to drop considerably (by more than \\$$70/MWh) as the penetration of solar increases toward 30\\percent on an energy basis. This is due primarily to a steep drop in capacity value followed by a decrease in energy value. In contrast, the value of CSP with thermal storage drops much less dramatically as penetration increases. As a result, at solar penetration levels above 10\\percent, CSP with thermal storage is found to be considerably more valuable relative to PV and CSP without thermal storage. The marginal economic value of wind is found to be largely driven by energy value, and is lower than solar at low penetration. The marginal economic value of wind drops at a relatively slower rate with penetration, however. As a result, at high penetration, the value of wind can exceed the value of PV and CSP without thermal storage. Though some of these findings may be somewhat unique to the specific case study presented here, the results: (1) highlight the importance of an analysis framework that addresses long-term investment decisions as well as short-term dispatch and operational constraints, (2) can help inform long-term decisions about renewable energy procurement and supporting infrastructure, and (3) point to areas where further research is warranted.« less

  17. Cost-effectiveness analysis of once-yearly injection of zoledronic acid for the treatment of osteoporosis in Japan.

    PubMed

    Moriwaki, K; Mouri, M; Hagino, H

    2017-06-01

    Model-based economic evaluation was performed to assess the cost-effectiveness of zoledronic acid. Although zoledronic acid was dominated by alendronate, the incremental quality-adjusted life year (QALY) was quite small in extent. Considering the advantage of once-yearly injection of zoledronic acid in persistence, zoledronic acid might be a cost-effective treatment option compared to once-weekly oral alendronate. The purpose of this study was to estimate the cost-effectiveness of once-yearly injection of zoledronic acid for the treatment of osteoporosis in Japan. A patient-level state-transition model was developed to predict the outcome of patients with osteoporosis who have experienced a previous vertebral fracture. The efficacy of zoledronic acid was derived from a published network meta-analysis. Lifetime cost and QALYs were estimated for patients who had received zoledronic acid, alendronate, or basic treatment alone. The incremental cost-effectiveness ratio (ICER) of zoledronic acid was estimated. For patients 70 years of age, zoledronic acid was dominated by alendronate with incremental QALY of -0.004 to -0.000 and incremental cost of 430 USD to 493 USD. Deterministic sensitivity analysis indicated that the relative risk of hip fracture and drug cost strongly affected the cost-effectiveness of zoledronic acid compared to alendronate. Scenario analysis considering treatment persistence showed that the ICER of zoledronic acid compared to alendronate was estimated to be 47,435 USD, 27,018 USD, and 10,749 USD per QALY gained for patients with a T-score of -2.0, -2.5, or -3.0, respectively. Although zoledronic acid is dominated by alendronate, the incremental QALY is quite small in extent. Considering the advantage of annual zoledronic acid treatment in compliance and persistence, zoledronic acid may be a cost-effective treatment option compared to alendronate.

  18. 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.

  19. Cost-effectiveness of a motivational intervention for alcohol-involved youth in a hospital emergency department.

    PubMed

    Neighbors, Charles J; Barnett, Nancy P; Rohsenow, Damaris J; Colby, Suzanne M; Monti, Peter M

    2010-05-01

    Brief interventions in the emergency department targeting risk-taking youth show promise to reduce alcohol-related injury. This study models the cost-effectiveness of a motivational interviewing-based intervention relative to brief advice to stop alcohol-related risk behaviors (standard care). Average cost-effectiveness ratios were compared between conditions. In addition, a cost-utility analysis examined the incremental cost of motivational interviewing per quality-adjusted life year gained. Microcosting methods were used to estimate marginal costs of motivational interviewing and standard care as well as two methods of patient screening: standard emergency-department staff questioning and proactive outreach by counseling staff. Average cost-effectiveness ratios were computed for drinking and driving, injuries, vehicular citations, and negative social consequences. Using estimates of the marginal effect of motivational interviewing in reducing drinking and driving, estimates of traffic fatality risk from drinking-and-driving youth, and national life tables, the societal costs per quality-adjusted life year saved by motivational interviewing relative to standard care were also estimated. Alcohol-attributable traffic fatality risks were estimated using national databases. Intervention costs per participant were $81 for standard care, $170 for motivational interviewing with standard screening, and $173 for motivational interviewing with proactive screening. The cost-effectiveness ratios for motivational interviewing were more favorable than standard care across all study outcomes and better for men than women. The societal cost per quality-adjusted life year of motivational interviewing was $8,795. Sensitivity analyses indicated that results were robust in terms of variability in parameter estimates. This brief intervention represents a good societal investment compared with other commonly adopted medical interventions.

  20. Using discharge data to reduce structural deficits in a hydrological model with a Bayesian inference approach and the implications for the prediction of critical source areas

    NASA Astrophysics Data System (ADS)

    Frey, M. P.; Stamm, C.; Schneider, M. K.; Reichert, P.

    2011-12-01

    A distributed hydrological model was used to simulate the distribution of fast runoff formation as a proxy for critical source areas for herbicide pollution in a small agricultural catchment in Switzerland. We tested to what degree predictions based on prior knowledge without local measurements could be improved upon relying on observed discharge. This learning process consisted of five steps: For the prior prediction (step 1), knowledge of the model parameters was coarse and predictions were fairly uncertain. In the second step, discharge data were used to update the prior parameter distribution. Effects of uncertainty in input data and model structure were accounted for by an autoregressive error model. This step decreased the width of the marginal distributions of parameters describing the lower boundary (percolation rates) but hardly affected soil hydraulic parameters. Residual analysis (step 3) revealed model structure deficits. We modified the model, and in the subsequent Bayesian updating (step 4) the widths of the posterior marginal distributions were reduced for most parameters compared to those of the prior. This incremental procedure led to a strong reduction in the uncertainty of the spatial prediction. Thus, despite only using spatially integrated data (discharge), the spatially distributed effect of the improved model structure can be expected to improve the spatially distributed predictions also. The fifth step consisted of a test with independent spatial data on herbicide losses and revealed ambiguous results. The comparison depended critically on the ratio of event to preevent water that was discharged. This ratio cannot be estimated from hydrological data only. The results demonstrate that the value of local data is strongly dependent on a correct model structure. An iterative procedure of Bayesian updating, model testing, and model modification is suggested.

  1. Strategies for the prevention of perinatal hepatitis B transmission in a marginalized population on the Thailand-Myanmar border: a cost-effectiveness analysis.

    PubMed

    Devine, Angela; Harvey, Rebecca; Min, Aung Myat; Gilder, Mary Ellen T; Paw, Moo Koh; Kang, Joy; Watts, Isabella; Hanboonkunupakarn, Borimas; Nosten, François; McGready, Rose

    2017-08-09

    Data on the cost effectiveness of hepatitis B virus (HBV) screening and vaccination strategies for prevention of vertical transmission of HBV in resource limited settings is sparse. A decision tree model of HBV prevention strategies utilised data from a cohort of 7071 pregnant women on the Thailand-Myanmar border using a provider perspective. All options included universal HBV vaccination for newborns in three strategies: (1) universal vaccination alone; (2) universal vaccination with screening of women during antenatal visits with rapid diagnostic test (RDT) plus HBV immune globulin (HBIG) administration to newborns of HBV surface antigen positive women; and (3) universal vaccination with screening of women during antenatal visits plus HBIG administration to newborns of women testing HBV e antigen positive by confirmatory test. At the time of the study, the HBIG after confirmatory test strategy was used. The costs in United States Dollars (US$), infections averted and incremental cost effectiveness ratios (ICERs) were calculated and sensitivity analyses were conducted. A willingness to pay threshold of US$1200 was used. The universal HBV vaccination was the least costly option at US$4.33 per woman attending the clinic. The HBIG after (RDT) strategy had an ICER of US$716.78 per infection averted. The HBIG after confirmatory test strategy was not cost-effective due to extended dominance. The one-way sensitivity analysis showed that while the transmission parameters and cost of HBIG had the biggest impact on outcomes, the HBIG after confirmatory test only became a cost-effective option when a low test cost was used or a high HBIG cost was used. The probabilistic sensitivity analysis showed that HBIG after RDT had an 87% likelihood of being cost-effective as compared to vaccination only at a willingness to pay threshold of US$1200. HBIG following confirmatory test is not a cost-effective strategy for preventing vertical transmission of HBV in the Thailand-Myanmar border population. By switching to HBIG following rapid diagnostic test, perinatal infections will be reduced by nearly one third. This strategy may be applicable to similar settings for marginalized populations where the confirmatory test is not logistically possible.

  2. The balanced scorecard: an incremental approach model to health care management.

    PubMed

    Pineno, Charles J

    2002-01-01

    The balanced scorecard represents a technique used in strategic management to translate an organization's mission and strategy into a comprehensive set of performance measures that provide the framework for implementation of strategic management. This article develops an incremental approach for decision making by formulating a specific balanced scorecard model with an index of nonfinancial as well as financial measures. The incremental approach to costs, including profit contribution analysis and probabilities, allows decisionmakers to assess, for example, how their desire to meet different health care needs will cause changes in service design. This incremental approach to the balanced scorecard may prove to be useful in evaluating the existence of causality relationships between different objective and subjective measures to be included within the balanced scorecard.

  3. Complexity of the heart rhythm after heart transplantation by entropy of transition network for RR-increments of RR time intervals between heartbeats.

    PubMed

    Makowiec, Danuta; Struzik, Zbigniew; Graff, Beata; Wdowczyk-Szulc, Joanna; Zarczynska-Buchnowiecka, Marta; Gruchala, Marcin; Rynkiewicz, Andrzej

    2013-01-01

    Network models have been used to capture, represent and analyse characteristics of living organisms and general properties of complex systems. The use of network representations in the characterization of time series complexity is a relatively new but quickly developing branch of time series analysis. In particular, beat-to-beat heart rate variability can be mapped out in a network of RR-increments, which is a directed and weighted graph with vertices representing RR-increments and the edges of which correspond to subsequent increments. We evaluate entropy measures selected from these network representations in records of healthy subjects and heart transplant patients, and provide an interpretation of the results.

  4. The effect of narrow-band noise maskers on increment detection1

    PubMed Central

    Messersmith, Jessica J.; Patra, Harisadhan; Jesteadt, Walt

    2010-01-01

    It is often assumed that listeners detect an increment in the intensity of a pure tone by detecting an increase in the energy falling within the critical band centered on the signal frequency. A noise masker can be used to limit the use of signal energy falling outside of the critical band, but facets of the noise may impact increment detection beyond this intended purpose. The current study evaluated the impact of envelope fluctuation in a noise masker on thresholds for detection of an increment. Thresholds were obtained for detection of an increment in the intensity of a 0.25- or 4-kHz pedestal in quiet and in the presence of noise of varying bandwidth. Results indicate that thresholds for detection of an increment in the intensity of a pure tone increase with increasing bandwidth for an on-frequency noise masker, but are unchanged by an off-frequency noise masker. Neither a model that includes a modulation-filter-bank analysis of envelope modulation nor a model based on discrimination of spectral patterns can account for all aspects of the observed data. PMID:21110593

  5. SRWC bioenergy productivity and economic feasibility on marginal lands.

    PubMed

    Ghezehei, Solomon B; Shifflett, Shawn D; Hazel, Dennis W; Nichols, Elizabeth Guthrie

    2015-09-01

    Evolving bioenergy markets necessitate consideration of marginal lands for woody biomass production worldwide particularly the southeastern U.S., a prominent wood pellet exporter to Europe. Growing short rotation woody crops (SRWCs) on marginal lands minimizes concerns about using croplands for bioenergy production and reinforces sustainability of wood supply to existing and growing global biomass markets. We estimated mean annual aboveground green biomass increments (MAIs) and assessed economic feasibility of various operationally established (0.5 ha-109 ha) SRWC stands on lands used to mitigate environmental liabilities of municipal wastewater, livestock wastewater and sludge, and subsurface contamination by petroleum and pesticides. MAIs (Mg ha(-1) yr(-1)) had no consistent relationship with stand density or age. Non-irrigated Populus, Plantanus occidentalis L. and Pinus taeda L. stands produced 2.4-12.4 Mg ha(-1) yr(-1). Older, irrigated Taxodium distchum L., Fraxinus pennsylvanica L., and coppiced P. occidentalis stands had higher MAIs (10.6-21.3 Mg ha(-1) yr(-1)) than irrigated Liquidambar styraciflua L. and non-coppiced, irrigated P. occidentalis (8-18 Mg ha(-1) yr(-1)). Natural hardwood MAIs at 20-60 years were less than hardwood and P. taeda productivities at 5-20 years. Unlike weed control, irrigation and coppicing improved managed hardwood productivity. Rotation length affected economic outcomes although the returns were poor due to high establishment and maintenance costs, low productivities and low current stumpage values, which are expected to quickly change with development of robust global markets. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Toward Capturing Momentary Changes of Heart Rate Variability by a Dynamic Analysis Method

    PubMed Central

    Zhang, Haoshi; Zhu, Mingxing; Zheng, Yue; Li, Guanglin

    2015-01-01

    The analysis of heart rate variability (HRV) has been performed on long-term electrocardiography (ECG) recordings (12~24 hours) and short-term recordings (2~5 minutes), which may not capture momentary change of HRV. In this study, we present a new method to analyze the momentary HRV (mHRV). The ECG recordings were segmented into a series of overlapped HRV analysis windows with a window length of 5 minutes and different time increments. The performance of the proposed method in delineating the dynamics of momentary HRV measurement was evaluated with four commonly used time courses of HRV measures on both synthetic time series and real ECG recordings from human subjects and dogs. Our results showed that a smaller time increment could capture more dynamical information on transient changes. Considering a too short increment such as 10 s would cause the indented time courses of the four measures, a 1-min time increment (4-min overlapping) was suggested in the analysis of mHRV in the study. ECG recordings from human subjects and dogs were used to further assess the effectiveness of the proposed method. The pilot study demonstrated that the proposed analysis of mHRV could provide more accurate assessment of the dynamical changes in cardiac activity than the conventional measures of HRV (without time overlapping). The proposed method may provide an efficient means in delineating the dynamics of momentary HRV and it would be worthy performing more investigations. PMID:26172953

  7. Incremental development and prototyping in current laboratory software development projects: Preliminary analysis

    NASA Technical Reports Server (NTRS)

    Griesel, Martha Ann

    1988-01-01

    Several Laboratory software development projects that followed nonstandard development processes, which were hybrids of incremental development and prototyping, are being studied. Factors in the project environment leading to the decision to use a nonstandard development process and affecting its success are analyzed. A simple characterization of project environment based on this analysis is proposed, together with software development approaches which have been found effective for each category. These approaches include both documentation and review requirements.

  8. Restoration of shoulder biomechanics according to degree of repair completion in a cadaveric model of massive rotator cuff tear: importance of margin convergence and posterior cuff fixation.

    PubMed

    Oh, Joo Han; McGarry, Michelle H; Jun, Bong Jae; Gupta, Akash; Chung, Kyung Chil; Hwang, James; Lee, Thay Q

    2012-11-01

    Complete repair in massive rotator cuff tear may not be possible, allowing for only partial repair. However, the effect of partial repair on glenohumeral biomechanics has not been evaluated. Therefore, the purpose of this study was to compare the rotational range of motion (ROM), glenohumeral kinematics, and gap formation at the repaired tendon edge following massive cuff tear and repair according to the degree of repair completion. Posterior fixation will restore the altered biomechanics of massive rotator cuff tear. Controlled laboratory study. Eight cadaveric shoulders were tested at 0°, 30°, and 60° of abduction in the scapular plane. Muscle loading was applied based on physiological muscle cross-sectional area ratios. Maximum internal (MaxIR) and external rotations (MaxER) were measured. Humeral head apex (HHA) position and gap formation at the repaired tendon edge were measured using a MicroScribe from MaxIR to MaxER in 30° increments. Testing was performed for intact, massive cuff tear, complete repair, and 4 types of partial repair. A repeated-measures analysis of variance was used to determine significant differences. Massive tear significantly increased ROM and shifted HHA superiorly in MaxIR at all abduction angles (P < .05). The complete repair restored ROM to intact (P < .05), while all partial repairs did not. Abnormal HHA elevation due to massive tear was restored by all repairs (P < .05). Release of the anterior single row alone and release of the marginal convergence significantly increased gap formation at the anterior tendon edge (P < .05). This study emphasizes the importance of anterior fixation in massive cuff tear to restore rotational range of motion and decrease gap formation at the repaired tendon edge and of posterior fixation to restore abnormal glenohumeral kinematics due to massive cuff tear. If complete repair of massive cuff tear is not possible, posterior cuff (infraspinatus) repair is necessary to restore abnormal glenohumeral kinematics, and margin convergence anteriorly is recommended to decrease gap formation of the repaired tendon edge, which may provide a better biomechanical environment for healing.

  9. A new technique for the characterization of chaff elements

    NASA Astrophysics Data System (ADS)

    Scholfield, David; Myat, Maung; Dauby, Jason; Fesler, Jonathon; Bright, Jonathan

    2011-07-01

    A new technique for the experimental characterization of electromagnetic chaff based on Inverse Synthetic Aperture Radar is presented. This technique allows for the characterization of as few as one filament of chaff in a controlled anechoic environment allowing for stability and repeatability of experimental results. This approach allows for a deeper understanding of the fundamental phenomena of electromagnetic scattering from chaff through an incremental analysis approach. Chaff analysis can now begin with a single element and progress through the build-up of particles into pseudo-cloud structures. This controlled incremental approach is supported by an identical incremental modeling and validation process. Additionally, this technique has the potential to produce considerable savings in financial and schedule cost and provides a stable and repeatable experiment to aid model valuation.

  10. The Decremental Protocol as an Alternative Protocol to Measure Maximal Oxygen Consumption in Athletes.

    PubMed

    Taylor, Katrina; Seegmiller, Jeffrey; Vella, Chantal A

    2016-11-01

    To determine whether a decremental protocol could elicit a higher maximal oxygen consumption (VO 2 max) than an incremental protocol in trained participants. A secondary aim was to examine whether cardiac-output (Q) and stroke-volume (SV) responses differed between decremental and incremental protocols in this sample. Nineteen runners/triathletes were randomized to either the decremental or incremental group. All participants completed an initial incremental VO 2 max test on a treadmill, followed by a verification phase. The incremental group completed 2 further incremental tests. The decremental group completed a second VO 2 max test using the decremental protocol, based on their verification phase. The decremental group then completed a final incremental test. During each test, VO 2 , ventilation, and heart rate were measured, and cardiac variables were estimated with thoracic bioimpedance. Repeated-measures analysis of variance was conducted with an alpha level set at .05. There were no significant main effects for group (P = .37) or interaction (P = .10) over time (P = .45). VO 2 max was similar between the incremental (57.29 ± 8.94 mL · kg -1 · min -1 ) and decremental (60.82 ± 8.49 mL · kg -1 · min -1 ) groups over time. Furthermore, Q and SV were similar between the incremental (Q 22.72 ± 5.85 L/min, SV 119.64 ± 33.02 mL/beat) and decremental groups (Q 20.36 ± 4.59 L/min, SV 109.03 ± 24.27 mL/beat) across all 3 trials. The findings suggest that the decremental protocol does not elicit higher VO 2 max than an incremental protocol but may be used as an alternative protocol to measure VO 2 max in runners and triathletes.

  11. Dental caries increments and related factors in children with type 1 diabetes mellitus.

    PubMed

    Siudikiene, J; Machiulskiene, V; Nyvad, B; Tenovuo, J; Nedzelskiene, I

    2008-01-01

    The aim of this study was to analyse possible associations between caries increments and selected caries determinants in children with type 1 diabetes mellitus and their age- and sex-matched non-diabetic controls, over 2 years. A total of 63 (10-15 years old) diabetic and non-diabetic pairs were examined for dental caries, oral hygiene and salivary factors. Salivary flow rates, buffer effect, concentrations of mutans streptococci, lactobacilli, yeasts, total IgA and IgG, protein, albumin, amylase and glucose were analysed. Means of 2-year decayed/missing/filled surface (DMFS) increments were similar in diabetics and their controls. Over the study period, both unstimulated and stimulated salivary flow rates remained significantly lower in diabetic children compared to controls. No differences were observed in the counts of lactobacilli, mutans streptococci or yeast growth during follow-up, whereas salivary IgA, protein and glucose concentrations were higher in diabetics than in controls throughout the 2-year period. Multivariable linear regression analysis showed that children with higher 2-year DMFS increments were older at baseline and had higher salivary glucose concentrations than children with lower 2-year DMFS increments. Likewise, higher 2-year DMFS increments in diabetics versus controls were associated with greater increments in salivary glucose concentrations in diabetics. Higher increments in active caries lesions in diabetics versus controls were associated with greater increments of dental plaque and greater increments of salivary albumin. Our results suggest that, in addition to dental plaque as a common caries risk factor, diabetes-induced changes in salivary glucose and albumin concentrations are indicative of caries development among diabetics. Copyright 2008 S. Karger AG, Basel.

  12. Route profile analysis system and method

    DOEpatents

    Mullenhoff, Donald J.; Wilson, Stephen W.

    1986-01-01

    A system for recording terrain profile information is disclosed. The system accurately senses incremental distances traveled by a vehicle along with vehicle inclination, recording both with elapsed time. The incremental distances can subsequently be differentiated with respect to time to obtain acceleration. The acceleration can then be used by the computer to correct the sensed inclination.

  13. Route profile analysis system and method

    DOEpatents

    Mullenhoff, D.J.; Wilson, S.W.

    1982-07-29

    A system for recording terrain profile information is disclosed. The system accurately senses incremental distances traveled by a vehicle along with vehicle inclination, recording both with elapsed time. The incremental distances can subsequently be differentiated with respect to time to obtain acceleration. The computer acceleration can then be used to correct the sensed inclination.

  14. The Trait Emotional Intelligence Questionnaire: Internal Structure, Convergent, Criterion, and Incremental Validity in an Italian Sample

    ERIC Educational Resources Information Center

    Andrei, Federica; Smith, Martin M.; Surcinelli, Paola; Baldaro, Bruno; Saklofske, Donald H.

    2016-01-01

    This study investigated the structure and validity of the Italian translation of the Trait Emotional Intelligence Questionnaire. Data were self-reported from 227 participants. Confirmatory factor analysis supported the four-factor structure of the scale. Hierarchical regressions also demonstrated its incremental validity beyond demographics, the…

  15. Incremental dynamical downscaling for probabilistic analysis based on multiple GCM projections

    NASA Astrophysics Data System (ADS)

    Wakazuki, Y.

    2015-12-01

    A dynamical downscaling method for probabilistic regional scale climate change projections was developed to cover an uncertainty of multiple general circulation model (GCM) climate simulations. The climatological increments (future minus present climate states) estimated by GCM simulation results were statistically analyzed using the singular vector decomposition. Both positive and negative perturbations from the ensemble mean with the magnitudes of their standard deviations were extracted and were added to the ensemble mean of the climatological increments. The analyzed multiple modal increments were utilized to create multiple modal lateral boundary conditions for the future climate regional climate model (RCM) simulations by adding to an objective analysis data. This data handling is regarded to be an advanced method of the pseudo-global-warming (PGW) method previously developed by Kimura and Kitoh (2007). The incremental handling for GCM simulations realized approximated probabilistic climate change projections with the smaller number of RCM simulations. Three values of a climatological variable simulated by RCMs for a mode were used to estimate the response to the perturbation of the mode. For the probabilistic analysis, climatological variables of RCMs were assumed to show linear response to the multiple modal perturbations, although the non-linearity was seen for local scale rainfall. Probability of temperature was able to be estimated within two modes perturbation simulations, where the number of RCM simulations for the future climate is five. On the other hand, local scale rainfalls needed four modes simulations, where the number of the RCM simulations is nine. The probabilistic method is expected to be used for regional scale climate change impact assessment in the future.

  16. Evaluation of an emergency department-based enrollment program for uninsured children.

    PubMed

    Mahajan, Prashant; Stanley, Rachel; Ross, Kevin W; Clark, Linda; Sandberg, Keisha; Lichtenstein, Richard

    2005-03-01

    We evaluate the effectiveness of an emergency department (ED)-based outreach program in increasing the enrollment of uninsured children. The study involved placing a full-time worker trained to enroll uninsured children into Medicaid or the State Children's Health Insurance Program in an inner-city academic children's hospital ED. Analysis was carried out for outpatient ED visits by insurance status, average revenue per patient from uninsured and insured children, proportion of patients enrolled in Medicaid and State Children's Health Insurance Program through this program, estimated incremental revenue from new enrollees, and program-specific incremental costs. A cost-benefit analysis and breakeven analysis was conducted to determine the impact of this intervention on ED revenues. Five thousand ninety-four uninsured children were treated during the 10 consecutive months assessed, and 4,667 were treated during program hours. One thousand eight hundred and three applications were filed, giving a program penetration rate of 39%. Eighty-four percent of applications filed were resolved (67% of these were Medicaid). Average revenue from each outpatient ED visit for Medicaid was US135.68 dollars, other insurance was US210.43 dollars, and uninsured was US15.03 dollars. Estimated incremental revenue for each uninsured patient converted to Medicaid was US120.65 dollars. Total annualized incremental revenue was US224,474 dollars, and the net incremental revenue, after accounting for program costs, was US157,414 dollars per year. A program enrolling uninsured children at an inner-city pediatric ED into government insurance was effective and generated revenue that paid for program costs.

  17. Evaluation of auxiliary power subsystems for gas engine heat pumps, phase 2

    NASA Astrophysics Data System (ADS)

    Rasmussen, R. W.; Wahlstedt, D. A.; Planer, N.; Fink, J.; Persson, E.

    1988-12-01

    The need to determine the practical, technical and economic viability for a stand-alone Gas Engine Heat Pump (GEHP) system capable of generating its own needed electricity is addressed. Thirty-eight reasonable design configurations were conceived based upon small-sized power conversion equipment that is either commercially available or close to emerging on the market. Nine of these configurations were analyzed due to their potential for low first cost, high conversion efficiency, availability or simplicity. It was found that electric consumption can be reduced by over 60 percent through the implementation of high efficiency, brushless, permanent magnet motors as fan and pump drivers. Of the nine selected configurations employing variable-speed fans, two were found to have simple incremental payback periods of 4.2 to 16 years, depending on the U.S. city chosen for analysis. Although the auxiliary power subsystem option is only marginally attractive from an economic standpoint, the increased gas load provided to the local gas utility may be sufficient to encourage further development. The ability of the system to operate completely disconnected from the electric power source may be a feature of high merit.

  18. Optimal approach for complete liver tumor ablation using radiofrequency ablation: a simulation study.

    PubMed

    Givehchi, Sogol; Wong, Yin How; Yeong, Chai Hong; Abdullah, Basri Johan Jeet

    2018-04-01

    To investigate the effect of radiofrequency ablation (RFA) electrode trajectory on complete tumor ablation using computational simulation. The RFA of a spherical tumor of 2.0 cm diameter along with 0.5 cm clinical safety margin was simulated using Finite Element Analysis software. A total of 86 points inside one-eighth of the tumor volume along the axial, sagittal and coronal planes were selected as the target sites for electrode-tip placement. The angle of the electrode insertion in both craniocaudal and orbital planes ranged from -90° to +90° with 30° increment. The RFA electrode was simulated to pass through the target site at different angles in combination of both craniocaudal and orbital planes before being advanced to the edge of the tumor. Complete tumor ablation was observed whenever the electrode-tip penetrated through the epicenter of the tumor regardless of the angles of electrode insertion in both craniocaudal and orbital planes. Complete tumor ablation can also be achieved by placing the electrode-tip at several optimal sites and angles. Identification of the tumor epicenter on the central slice of the axial images is essential to enhance the success rate of complete tumor ablation during RFA procedures.

  19. One-millimeter cancer-free margin is curative for colorectal liver metastases: a propensity score case-match approach.

    PubMed

    Hamady, Zaed Z R; Lodge, J Peter A; Welsh, Fenella K; Toogood, Giles J; White, Alan; John, Timothy; Rees, Myrddin

    2014-03-01

    To investigate the influence of clear surgical resection margin width on disease recurrence rate after intentionally curative resection of colorectal liver metastases. There is consensus that a histological positive resection margin is a predictor of disease recurrence after resection of colorectal liver metastases. The dispute, however, over the width of cancer-free resection margin required is ongoing. Analysis of observational prospectively collected data for 2715 patients who underwent primary resection of colorectal liver metastases from 2 major hepatobiliary units in the United Kingdom. Histological cancer-free resection margin was classified as positive (if cancer cells present at less than 1 mm from the resection margin) or negative (if the distance between the cancer and the margin is 1 mm or more). The negative margin was further classified according to the distance from the tumor in millimeters. Predictors of disease-free survival were analyzed in univariate and multivariate analyses. A case-match analysis by a propensity score method was undertaken to reduce bias. A 1-mm cancer-free resection margin was sufficient to achieve 33% 5-year overall disease-free survival. Extra margin width did not add disease-free survival advantage (P > 0.05). After the propensity case-match analysis, there is no statistical difference in disease-free survival between patients with negative narrow and wider margin clearance [hazard ratio (HR) 1.0; 95% (confidence interval) CI: 0.9-1.2; P = 0.579 at 5-mm cutoff and HR 1.1; 95% CI: 0.96-1.3; P = 0.149 at 10-mm cutoff]. Patients with extrahepatic disease and positive lymph node primary tumor did not have disease-free survival advantage despite surgical margin clearance (9 months for <1-mm vs 12 months for ≥1-mm margin clearance; P = 0.062). One-mm cancer-free resection margin achieved in patients with colorectal liver metastases should now be considered the standard of care.

  20. How to revive breakthrough innovation in the pharmaceutical industry.

    PubMed

    Munos, Bernard H; Chin, William W

    2011-06-29

    Over the past 20 years, pharmaceutical companies have implemented conservative management practices to improve the predictability of therapeutics discovery and success rates of drug candidates. This approach has often yielded compounds that are only marginally better than existing therapies, yet require larger, longer, and more complex trials. To fund them, companies have shifted resources away from drug discovery to late clinical development; this has hurt innovation and amplified the crisis brought by the expiration of patents on many best-selling drugs. Here, we argue that more breakthrough therapeutics will reach patients only if the industry ceases to pursue "safe" incremental innovation, re-engages in high-risk discovery research, and adopts collaborative innovation models that allow sharing of knowledge and costs among collaborators.

  1. Cost effectiveness analysis of immunotherapy in patients with grass pollen allergic rhinoconjunctivitis in Germany.

    PubMed

    Westerhout, K Y; Verheggen, B G; Schreder, C H; Augustin, M

    2012-01-01

    An economic evaluation was conducted to assess the outcomes and costs as well as cost-effectiveness of the following grass-pollen immunotherapies: OA (Oralair; Stallergenes S.A., Antony, France) vs GRZ (Grazax; ALK-Abelló, Hørsholm, Denmark), and ALD (Alk Depot SQ; ALK-Abelló) (immunotherapy agents alongside symptomatic medication) and symptomatic treatment alone for grass pollen allergic rhinoconjunctivitis. The costs and outcomes of 3-year treatment were assessed for a period of 9 years using a Markov model. Treatment efficacy was estimated using an indirect comparison of available clinical trials with placebo as a common comparator. Estimates for immunotherapy discontinuation, occurrence of asthma, health state utilities, drug costs, resource use, and healthcare costs were derived from published sources. The analysis was conducted from the insurant's perspective including public and private health insurance payments and co-payments by insurants. Outcomes were reported as quality-adjusted life years (QALYs) and symptom-free days. The uncertainty around incremental model results was tested by means of extensive deterministic univariate and probabilistic multivariate sensitivity analyses. In the base case analysis the model predicted a cost-utility ratio of OA vs symptomatic treatment of €14,728 per QALY; incremental costs were €1356 (95%CI: €1230; €1484) and incremental QALYs 0.092 (95%CI: 0.052; 0.140). OA was the dominant strategy compared to GRZ and ALD, with estimated incremental costs of -€1142 (95%CI: -€1255; -€1038) and -€54 (95%CI: -€188; €85) and incremental QALYs of 0.015 (95%CI: -0.025; 0.056) and 0.027 (95%CI: -0.022; 0.075), respectively. At a willingness-to-pay threshold of €20,000, the probability of OA being the most cost-effective treatment was predicted to be 79%. Univariate sensitivity analyses show that incremental outcomes were moderately sensitive to changes in efficacy estimates. The main study limitation was the requirement of an indirect comparison involving several steps to assess relative treatment effects. The analysis suggests OA to be cost-effective compared to GRZ and ALD, and a symptomatic treatment. Sensitivity analyses showed that uncertainty surrounding treatment efficacy estimates affected the model outcomes.

  2. MEDIAN-BASED INCREMENTAL COST-EFFECTIVENESS RATIOS WITH CENSORED DATA

    PubMed Central

    Bang, Heejung; Zhao, Hongwei

    2016-01-01

    Cost-effectiveness is an essential part of treatment evaluation, in addition to effectiveness. In the cost-effectiveness analysis, a measure called the incremental cost-effectiveness ratio (ICER) is widely utilized, and the mean cost and the mean (quality-adjusted) life years have served as norms to summarize cost and effectiveness for a study population. Recently, the median-based ICER was proposed for complementary or sensitivity analysis purposes. In this paper, we extend this method when some data are censored. PMID:26010599

  3. Using Data Assimilation Diagnostics to Assess the SMAP Level-4 Soil Moisture Product

    NASA Technical Reports Server (NTRS)

    Reichle, Rolf; Liu, Qing; De Lannoy, Gabrielle; Crow, Wade; Kimball, John; Koster, Randy; Ardizzone, Joe

    2018-01-01

    The Soil Moisture Active Passive (SMAP) mission Level-4 Soil Moisture (L4_SM) product provides 3-hourly, 9-km resolution, global estimates of surface (0-5 cm) and root-zone (0-100 cm) soil moisture and related land surface variables from 31 March 2015 to present with approx.2.5-day latency. The ensemble-based L4_SM algorithm assimilates SMAP brightness temperature (Tb) observations into the Catchment land surface model. This study describes the spatially distributed L4_SM analysis and assesses the observation-minus-forecast (O-F) Tb residuals and the soil moisture and temperature analysis increments. Owing to the climatological rescaling of the Tb observations prior to assimilation, the analysis is essentially unbiased, with global mean values of approx. 0.37 K for the O-F Tb residuals and practically zero for the soil moisture and temperature increments. There are, however, modest regional (absolute) biases in the O-F residuals (under approx. 3 K), the soil moisture increments (under approx. 0.01 cu m/cu m), and the surface soil temperature increments (under approx. 1 K). Typical instantaneous values are approx. 6 K for O-F residuals, approx. 0.01 (approx. 0.003) cu m/cu m for surface (root-zone) soil moisture increments, and approx. 0.6 K for surface soil temperature increments. The O-F diagnostics indicate that the actual errors in the system are overestimated in deserts and densely vegetated regions and underestimated in agricultural regions and transition zones between dry and wet climates. The O-F auto-correlations suggest that the SMAP observations are used efficiently in western North America, the Sahel, and Australia, but not in many forested regions and the high northern latitudes. A case study in Australia demonstrates that assimilating SMAP observations successfully corrects short-term errors in the L4_SM rainfall forcing.

  4. Global Assessment of the SMAP Level-4 Soil Moisture Product Using Assimilation Diagnostics

    NASA Technical Reports Server (NTRS)

    Reichle, Rolf; Liu, Qing; De Lannoy, Gabrielle; Crow, Wade; Kimball, John; Koster, Randy; Ardizzone, Joe

    2018-01-01

    The Soil Moisture Active Passive (SMAP) mission Level-4 Soil Moisture (L4_SM) product provides 3-hourly, 9-km resolution, global estimates of surface (0-5 cm) and root-zone (0-100 cm) soil moisture and related land surface variables from 31 March 2015 to present with approx. 2.5-day latency. The ensemble-based L4_SM algorithm assimilates SMAP brightness temperature (Tb) observations into the Catchment land surface model. This study describes the spatially distributed L4_SM analysis and assesses the observation-minus-forecast (O-F) Tb residuals and the soil moisture and temperature analysis increments. Owing to the climatological rescaling of the Tb observations prior to assimilation, the analysis is essentially unbiased, with global mean values of approx. 0.37 K for the O-F Tb residuals and practically zero for the soil moisture and temperature increments. There are, however, modest regional (absolute) biases in the O-F residuals (under approx. 3 K), the soil moisture increments (under approx. 0.01 cu m/cu m), and the surface soil temperature increments (under approx. 1 K). Typical instantaneous values are approx. 6 K for O-F residuals, approx. 0.01 (approx. 0.003) cu m/cu m for surface (root-zone) soil moisture increments, and approx. 0.6 K for surface soil temperature increments. The O-F diagnostics indicate that the actual errors in the system are overestimated in deserts and densely vegetated regions and underestimated in agricultural regions and transition zones between dry and wet climates. The O-F auto-correlations suggest that the SMAP observations are used efficiently in western North America, the Sahel, and Australia, but not in many forested regions and the high northern latitudes. A case study in Australia demonstrates that assimilating SMAP observations successfully corrects short-term errors in the L4_SM rainfall forcing.

  5. Why and how did Israel adopt activity-based hospital payment? The Procedure-Related Group incremental reform.

    PubMed

    Brammli-Greenberg, Shuli; Waitzberg, Ruth; Perman, Vadim; Gamzu, Ronni

    2016-10-01

    Historically, Israel paid its non-profit hospitals on a perdiem (PD) basis. Recently, like other OECD countries, Israel has moved to activity-based payments. While most countries have adopted a diagnostic related group (DRG) payment system, Israel has chosen a Procedure-Related Group (PRG) system. This differs from the DRG system because it classifies patients by procedure rather than diagnosis. In Israel, the PRG system was found to be more feasible given the lack of data and information needed in the DRG classification system. The Ministry of Health (MoH) chose a payment scheme that depends only on inhouse creation of PRG codes and costing, thus avoiding dependence on hospital data. The PRG tariffs are priced by a joint Health and Finance Ministry commission and updated periodically. Moreover, PRGs are believed to achieve the same main efficiency objectives as DRGs: increasing the volume of activity, shortening unnecessary hospitalization days, and reducing the gaps between the costs and prices of activities. The PRG system is being adopted through an incremental reform that started in 2002 and was accelerated in 2010. The Israeli MoH involved the main players in the hospital market in the consolidation of this potentially controversial reform in order to avoid opposition. The reform was implemented incrementally in order to preserve the balance of resource allocation and overall expenditures of the system, thus becoming budget neutral. Yet, as long as gaps remain between marginal costs and prices of procedures, PRGs will not attain all their objectives. Moreover, it is still crucial to refine PRG rates to reflect the severity of cases, in order to tackle incentives for selection of patients within each procedure. Copyright © 2016 The Author(s). Published by Elsevier Ireland Ltd.. All rights reserved.

  6. Lines of Evidence–Incremental Markings in Molar Enamel of Soay Sheep as Revealed by a Fluorochrome Labeling and Backscattered Electron Imaging Study

    PubMed Central

    Kierdorf, Horst; Kierdorf, Uwe; Frölich, Kai; Witzel, Carsten

    2013-01-01

    We studied the structural characteristics and periodicities of regular incremental markings in sheep enamel using fluorochrome injections for vital labeling of forming enamel and backscattered electron imaging in the scanning electron microscope. Microscopic analysis of mandibular first molars revealed the presence of incremental markings with a daily periodicity (laminations) that indicated successive positions of the forming front of interprismatic enamel. In addition to the laminations, incremental markings with a sub-daily periodicity were discernible both in interprismatic enamel and in enamel prisms. Five sub-daily increments were present between two consecutive laminations. Backscattered electron imaging revealed that each sub-daily growth increment consisted of a broader and more highly mineralized band and a narrower and less mineralized band (line). The sub-daily markings in the prisms of sheep enamel morphologically resembled the (daily) prisms cross striations seen in primate enamel. Incremental markings with a supra-daily periodicity were not observed in sheep enamel. Based on the periodicity of the incremental markings, maximum mean daily apposition rates of 17.0 µm in buccal enamel and of 13.4 µm in lingual enamel were recorded. Enamel extension rates were also high, with maximum means of 180 µm/day and 217 µm/day in upper crown areas of buccal and lingual enamel, respectively. Values in more cervical crown portions were markedly lower. Our results are in accordance with previous findings in other ungulate species. Using the incremental markings present in primate enamel as a reference could result in a misinterpretation of the incremental markings in ungulate enamel. Thus, the sub-daily growth increments in the prisms of ungulate enamel might be mistaken as prism cross striations with a daily periodicity, and the laminations misidentified as striae of Retzius with a supra-daily periodicity. This would lead to a considerable overestimation of crown formation times in ungulate teeth. PMID:24040293

  7. International Space Station Increment Operations Services

    NASA Astrophysics Data System (ADS)

    Michaelis, Horst; Sielaff, Christian

    2002-01-01

    The Industrial Operator (IO) has defined End-to-End services to perform efficiently all required operations tasks for the Manned Space Program (MSP) as agreed during the Ministerial Council in Edinburgh in November 2001. Those services are the result of a detailed task analysis based on the operations processes as derived from the Space Station Program Implementation Plans (SPIP) and defined in the Operations Processes Documents (OPD). These services are related to ISS Increment Operations and ATV Mission Operations. Each of these End-to-End services is typically characterised by the following properties: It has a clearly defined starting point, where all requirements on the end-product are fixed and associated performance metrics of the customer are well defined. It has a clearly defined ending point, when the product or service is delivered to the customer and accepted by him, according to the performance metrics defined at the start point. The implementation of the process might be restricted by external boundary conditions and constraints mutually agreed with the customer. As far as those are respected the IO has the free choice to select methods and means of implementation. The ISS Increment Operations Service (IOS) activities required for the MSP Exploitation program cover the complete increment specific cycle starting with the support to strategic planning and ending with the post increment evaluation. These activities are divided into sub-services including the following tasks: - ISS Planning Support covering the support to strategic and tactical planning up to the generation - Development &Payload Integration Support - ISS Increment Preparation - ISS Increment Execution These processes are tight together by the Increment Integration Management, which provides the planning and scheduling of all activities as well as the technical management of the overall process . The paper describes the entire End-to-End ISS Increment Operations service and the implementation to support the Columbus Flight 1E related increment and subsequent ISS increments. Special attention is paid to the implications caused by long term operations on hardware, software and operations personnel.

  8. Contact stresses in meshing spur gear teeth: Use of an incremental finite element procedure

    NASA Technical Reports Server (NTRS)

    Hsieh, Chih-Ming; Huston, Ronald L.; Oswald, Fred B.

    1992-01-01

    Contact stresses in meshing spur gear teeth are examined. The analysis is based upon an incremental finite element procedure that simultaneously determines the stresses in the contact region between the meshing teeth. The teeth themselves are modeled by two dimensional plain strain elements. Friction effects are included, with the friction forces assumed to obey Coulomb's law. The analysis assumes that the displacements are small and that the tooth materials are linearly elastic. The analysis procedure is validated by comparing its results with those for the classical two contacting semicylinders obtained from the Hertz method. Agreement is excellent.

  9. Statistically Controlling for Confounding Constructs Is Harder than You Think

    PubMed Central

    Westfall, Jacob; Yarkoni, Tal

    2016-01-01

    Social scientists often seek to demonstrate that a construct has incremental validity over and above other related constructs. However, these claims are typically supported by measurement-level models that fail to consider the effects of measurement (un)reliability. We use intuitive examples, Monte Carlo simulations, and a novel analytical framework to demonstrate that common strategies for establishing incremental construct validity using multiple regression analysis exhibit extremely high Type I error rates under parameter regimes common in many psychological domains. Counterintuitively, we find that error rates are highest—in some cases approaching 100%—when sample sizes are large and reliability is moderate. Our findings suggest that a potentially large proportion of incremental validity claims made in the literature are spurious. We present a web application (http://jakewestfall.org/ivy/) that readers can use to explore the statistical properties of these and other incremental validity arguments. We conclude by reviewing SEM-based statistical approaches that appropriately control the Type I error rate when attempting to establish incremental validity. PMID:27031707

  10. Volatilities, Traded Volumes, and Price Increments in Derivative Securities

    NASA Astrophysics Data System (ADS)

    Kim, Kyungsik; Lim, Gyuchang; Kim, Soo Yong; Scalas, Enrico

    2007-03-01

    We apply the detrended fluctuation analysis (DFA) to the statistics of the Korean treasury bond (KTB) futures from which the logarithmic increments, volatilities, and traded volumes are estimated over a specific time lag. For our case, the logarithmic increment of futures prices has no long-memory property, while the volatility and the traded volume exhibit the existence of long-memory property. To analyze and calculate whether the volatility clustering is due to the inherent higher-order correlation not detected by applying directly the DFA to logarithmic increments of the KTB futures, it is of importance to shuffle the original tick data of futures prices and to generate the geometric Brownian random walk with the same mean and standard deviation. It is really shown from comparing the three tick data that the higher-order correlation inherent in logarithmic increments makes the volatility clustering. Particularly, the result of the DFA on volatilities and traded volumes may be supported the hypothesis of price changes.

  11. Volatilities, traded volumes, and the hypothesis of price increments in derivative securities

    NASA Astrophysics Data System (ADS)

    Lim, Gyuchang; Kim, SooYong; Scalas, Enrico; Kim, Kyungsik

    2007-08-01

    A detrended fluctuation analysis (DFA) is applied to the statistics of Korean treasury bond (KTB) futures from which the logarithmic increments, volatilities, and traded volumes are estimated over a specific time lag. In this study, the logarithmic increment of futures prices has no long-memory property, while the volatility and the traded volume exhibit the existence of the long-memory property. To analyze and calculate whether the volatility clustering is due to a inherent higher-order correlation not detected by with the direct application of the DFA to logarithmic increments of KTB futures, it is of importance to shuffle the original tick data of future prices and to generate a geometric Brownian random walk with the same mean and standard deviation. It was found from a comparison of the three tick data that the higher-order correlation inherent in logarithmic increments leads to volatility clustering. Particularly, the result of the DFA on volatilities and traded volumes can be supported by the hypothesis of price changes.

  12. Cost-Effectiveness of a Specialized Oral Nutritional Supplementation for Malnourished Older Adult Patients in Spain

    PubMed Central

    Martínez Llinàs, Diana; Goates, Scott; Sanz Barriuso, Rebeca; Sanz-Paris, Alejandro

    2018-01-01

    Malnutrition has been related to prolonged hospital stays, and to increases in readmission and mortality rates. In the NOURISH (Nutrition effect On Unplanned Readmissions and Survival in Hospitalized patients) study, administering a high protein oral nutritional supplement (ONS) containing beta-hydroxy-beta-methylbutyrate (HP-HMB) to hospitalised older adult patients led to a significant improvement in survival compared with a placebo treatment. The aim of this study was to determine whether HP-HMB would be cost-effective in Spain. We performed a cost-effectiveness analysis from the perspective of the Spanish National Health System using time horizons of 90 days, 180 days, 1 year, 2 years, 5 years and lifetime. The difference in cost between patients treated with HP-HMB and placebo was €332.75. With the 90 days time horizon, the difference in life years gained (LYG) between both groups was 0.0096, resulting in an incremental cost-effectiveness ratio (ICER) of €34,700.62/LYG. With time horizons of 180 days, 1 year, 2 years, 5 years and lifetime, the respective ICERs were €13,711.68, €3377.96, €2253.32, €1127.34 and €563.84/LYG. This analysis suggests that administering HP-HMB to older adult patients admitted to Spanish hospitals during hospitalisation and after discharge could be a cost-effective intervention that would improve survival with a reduced marginal cost. PMID:29470402

  13. Inverse Analysis to Formability Design in a Deep Drawing Process

    NASA Astrophysics Data System (ADS)

    Buranathiti, Thaweepat; Cao, Jian

    Deep drawing process is an important process adding values to flat sheet metals in many industries. An important concern in the design of a deep drawing process generally is formability. This paper aims to present the connection between formability and inverse analysis (IA), which is a systematical means for determining an optimal blank configuration for a deep drawing process. In this paper, IA is presented and explored by using a commercial finite element software package. A number of numerical studies on the effect of blank configurations to the quality of a part produced by a deep drawing process were conducted and analyzed. The quality of the drawing processes is numerically analyzed by using an explicit incremental nonlinear finite element code. The minimum distance between elemental principal strains and the strain-based forming limit curve (FLC) is defined as tearing margin to be the key performance index (KPI) implying the quality of the part. The initial blank configuration has shown that it plays a highly important role in the quality of the product via the deep drawing process. In addition, it is observed that if a blank configuration is not greatly deviated from the one obtained from IA, the blank can still result a good product. The strain history around the bottom fillet of the part is also observed. The paper concludes that IA is an important part of the design methodology for deep drawing processes.

  14. The cost-effectiveness of immediate treatment or watch and wait with deferred chemotherapy for advanced asymptomatic follicular lymphoma.

    PubMed

    Prettyjohns, Matthew; Hoskin, Peter; McNamara, Christopher; Linch, David

    2018-01-01

    Recent evidence has shown that immediate treatment with rituximab induction, with and without maintenance, substantially reduces the need for further treatment in patients with advanced asymptomatic follicular lymphoma. This analysis estimates the cost-effectiveness of immediate treatment approaches in comparison to a watch and wait approach from the perspective of the UK National Health Service. A Markov decision model was developed to estimate the cost-effectiveness of treatment strategies in patients with asymptomatic follicular lymphoma. The model was populated using effectiveness data from a systematic literature review with the key clinical data sourced from a randomised trial, in which the treatment strategies were compared. Costs were estimated using UK national sources. In comparison to watchful waiting, both rituximab strategies were found to be more effective and cost saving. In comparison to rituximab induction, the addition of rituximab maintenance marginally increased effectiveness but substantially increased costs, resulting in an incremental cost-effectiveness ratio (ICER) of £69 406 per quality-adjusted life year (QALY). In probabilistic sensitivity analysis, rituximab induction was found to have a 68% probability of being cost-effective at a threshold of £20 000 per QALY. In conclusion, active treatment with rituximab induction is a cost-effective strategy to adopt in patients with asymptomatic follicular lymphoma. © 2017 John Wiley & Sons Ltd.

  15. Fast online replanning for interfraction rotation correction in prostate radiotherapy.

    PubMed

    Kontaxis, Charis; Bol, Gijsbert H; Kerkmeijer, Linda G W; Lagendijk, Jan J W; Raaymakers, Bas W

    2017-10-01

    To enable fast online replanning for prostate radiotherapy with the inclusion of interfraction rotations and translations and investigate the possibility for margin reduction via this regime. Online daily replanning for a 35-fraction treatment for five prostate cases is simulated while accounting for anatomical transformations derived from fiducial marker data available in our clinic. Two online replanning strategies were simulated, compensating for: (a) rotation-only in combination with a couch shift and (b) both translation and rotation without a couch shift. They were compared against our current clinical protocol consisting of a single offline plan used over all fractions with daily couch repositioning (translations only). For every patient, the above methods were generated for several planning margins (0-8 mm with 2 mm increments) in order to assess the performance of online replanning in terms of target coverage and investigate the possible dosimetric benefit for the organs at risk. The daily DVHs for each treatment strategy were used for evaluation and the non tumor integral dose (NTID) for the different margins was calculated in order to quantify the overall reduction of the delivered energy to the patient. Our system is able to generate a daily automated prostate plan in less than 2 min. For every patient, the daily treatment plans produce similar dose distributions to the original approved plan (average CTV D99 relative difference: 0.2%). The inclusion of both shifts and rotations can be effectively compensated via replanning among all planning margins (average CTV D99 difference: 0.01 Gy between the two replanning regimes). Online replanning is able to maintain target coverage among all margins, while - as expected - the conventional treatment plan is increasingly affected by the interfraction rotations as the margins shrink (average CTV D99 decrease: 0.2 Gy at 8 mm to 2.9 Gy at 0 mm margin). The possible gain in total delivered energy to the patient was quantified by the decreased NTID ranging from 12.6% at 6 mm to 32.9% at 0 mm. We demonstrate that fast daily replanning can be utilized to account for daily rotations and translations based on the daily positioning protocol. A daily plan can be generated from scratch in less than 2 min making it suitable for online application. Given the large magnitude of prostate rotation around the LR axis, online correction for daily rotations can be beneficial even for the clinical 8 mm margin and could be utilized for treatments with small margin reduction mainly limited then by anatomical deformations and intrafraction motion. Our online replanning pipeline can be used in future treatments with online MR guidance that can lead to further safe reduction of the planning margins. © 2017 The Authors. Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

  16. Anterior Aortic Plane Systolic Excursion: A Novel Indicator of Transplant-Free Survival in Systemic Light-Chain Amyloidosis.

    PubMed

    Ochs, Marco M; Riffel, Johannes; Kristen, Arnt V; Hegenbart, Ute; Schönland, Stefan; Hardt, Stefan E; Katus, Hugo A; Mereles, Derliz; Buss, Sebastian J

    2016-12-01

    Anterior aortic plane systolic excursion (AAPSE) was evaluated in the present pilot study as a novel echocardiographic indicator of transplant-free survival in patients with systemic light-chain amyloidosis. Eighty-nine patients with light-chain amyloidosis were included in the post-hoc analysis. A subgroup of 54 patients with biopsy-proven cardiac amyloid infiltration were compared with 41 healthy individuals to evaluate the discriminative ability of echocardiographic findings. AAPSE is defined as the systolic excursion of the anterior aortic margin. To quantify AAPSE, the M-mode cursor was placed on the aortic valve plane in parasternal long-axis view at end-diastole. Index echocardiography had been performed before chemotherapy. Median follow-up duration was 2.4 years. The primary combined end point was heart transplantation or overall death. Mean AAPSE was 14 ± 2 mm in healthy individuals (mean age=57 ± 10 years; 56% men; BMI=25 ± 4 kg/m 2 ). AAPSE < 11 mm separated patients from age-, gender-, and BMI-matched control subjects with 93% sensitivity and 97% specificity. Median transplant-free survival of patients with AAPSE < 5 mm was 0.7 versus 4.8 years (P = .0001). AAPSE was an independent indicator of transplant-free survival in multivariate Cox regression (echocardiographic model: hazard ratio=0.72 [P = .03]; biomarker model: hazard ratio=0.62 [P = .0001]). Sequential regression analysis suggested incremental power of AAPSE as a marker of transplant-free survival. An ejection fraction-based model with an overall χ 2 value of 22.8 was improved by the addition of log NT-proBNP (χ 2  = 32.6, P < .005), troponin-T (χ 2  = 39.6, P < .01), and AAPSE (χ 2  = 54.0, P < .0001). AAPSE is suggested as an indicator of transplant-free survival in patients with systemic light-chain amyloidosis. AAPSE provided significant incremental value to established staging models. Copyright © 2016 American Society of Echocardiography. Published by Elsevier Inc. All rights reserved.

  17. Lithosphere structure and subsidence evolution of the conjugate S-African and Argentine margins

    NASA Astrophysics Data System (ADS)

    Dressel, Ingo; Scheck-Wenderoth, Magdalena; Cacace, Mauro; Götze, Hans-Jürgen; Franke, Dieter

    2016-04-01

    The bathymetric evolution of the South Atlantic passive continental margins is a matter of debate. Though it is commonly accepted that passive margins experience thermal subsidence as a result of lithospheric cooling as well as load induced subsidence in response to sediment deposition it is disputed if the South Atlantic passive margins were affected by additional processes affecting the subsidence history after continental breakup. We present a subsidence analysis along the SW African margin and offshore Argentina and restore paleobathymetries to assess the subsidence evolution of the margin. These results are discussed with respect to mechanisms behind margin evolution. Therefore, we use available information about the lithosphere-scale present-day structural configuration of these margins as a starting point for the subsidence analysis. A multi 1D backward modelling method is applied to separate individual subsidence components such as the thermal- as well as the load induced subsidence and to restore paleobathymetries for the conjugate margins. The comparison of the restored paleobathymetries shows that the conjugate margins evolve differently: Continuous subsidence is obtained offshore Argentina whereas the subsidence history of the SW African margin is interrupted by phases of uplift. This differing results for both margins correlate also with different structural configurations of the subcrustal mantle. In the light of these results we discuss possible implications for uplift mechanisms.

  18. Optimal tree increment models for the Northeastern United Statesq

    Treesearch

    Don C. Bragg

    2003-01-01

    used the potential relative increment (PRI) methodology to develop optimal tree diameter growth models for the Northeastern United States. Thirty species from the Eastwide Forest Inventory Database yielded 69,676 individuals, which were then reduced to fast-growing subsets for PRI analysis. For instance, only 14 individuals from the greater than 6,300-tree eastern...

  19. Optimal Tree Increment Models for the Northeastern United States

    Treesearch

    Don C. Bragg

    2005-01-01

    I used the potential relative increment (PRI) methodology to develop optimal tree diameter growth models for the Northeastern United States. Thirty species from the Eastwide Forest Inventory Database yielded 69,676 individuals, which were then reduced to fast-growing subsets for PRI analysis. For instance, only 14 individuals from the greater than 6,300-tree eastern...

  20. High-resolution analysis of stem increment and sap flow for loblolly pine trees attacked by southern pine beetle

    Treesearch

    Stan D. Wullschleger; Samuel B. McLaughlin; Matthew P. Ayres

    2004-01-01

    Manual and automated dendrometers, and thermal dissipation probes were used to measure stem increment and sap flow for loblolly pine (Pinus taeda L.) trees attacked by southern pine beetle (Dendroctonus frontalis Zimm.) in east Tennessee, USA. Seasonal-long measurements with manual dendrometers indicated linear increases in stem...

  1. Mathematic analysis of incremental packing density with detachable coils: does that last coil matter much?

    PubMed

    Taussky, P; Kallmes, D F; Cloft, H

    2012-05-01

    Higher packing attenuation of coils in cerebral aneurysms is associated with a decreased recurrence rate. However, geometric relationships suggest that an additional coil may have very little effect on packing attenuation as aneurysm size increases. We mathematically evaluated the relationship between aneurysm size and incremental packing attenuation for coils currently available.

  2. On the Accuracy and Parallelism of GPGPU-Powered Incremental Clustering Algorithms.

    PubMed

    Chen, Chunlei; He, Li; Zhang, Huixiang; Zheng, Hao; Wang, Lei

    2017-01-01

    Incremental clustering algorithms play a vital role in various applications such as massive data analysis and real-time data processing. Typical application scenarios of incremental clustering raise high demand on computing power of the hardware platform. Parallel computing is a common solution to meet this demand. Moreover, General Purpose Graphic Processing Unit (GPGPU) is a promising parallel computing device. Nevertheless, the incremental clustering algorithm is facing a dilemma between clustering accuracy and parallelism when they are powered by GPGPU. We formally analyzed the cause of this dilemma. First, we formalized concepts relevant to incremental clustering like evolving granularity. Second, we formally proved two theorems. The first theorem proves the relation between clustering accuracy and evolving granularity. Additionally, this theorem analyzes the upper and lower bounds of different-to-same mis-affiliation. Fewer occurrences of such mis-affiliation mean higher accuracy. The second theorem reveals the relation between parallelism and evolving granularity. Smaller work-depth means superior parallelism. Through the proofs, we conclude that accuracy of an incremental clustering algorithm is negatively related to evolving granularity while parallelism is positively related to the granularity. Thus the contradictory relations cause the dilemma. Finally, we validated the relations through a demo algorithm. Experiment results verified theoretical conclusions.

  3. Structure of analysis-minus-observation misfits within a global ocean reanalysis system: implications for atmospheric reanalyses

    NASA Astrophysics Data System (ADS)

    Carton, James; Chepurin, Gennady

    2017-04-01

    While atmospheric reanalyses do not ingest data from the subsurface ocean they must produce fluxes consistent with, for example, ocean storage and divergence of heat transport. Here we present a test of the consistency of two different atmospheric reanalyses with 2.5 million global ocean temperature observations during the data-rich eight year period 2007-2014. The examination is carried out by using atmospheric reanalysis variables to drive the SODA3 ocean reanalysis system, and then collecting and analyzing the temperature analysis increments (observation misfits). For the widely used MERRA2 and ERA-Int atmospheric reanalyses the temperature analysis increments reveal inconsistencies between those atmospheric fluxes and the ocean observations in the range of 10-30 W/m2. In the interior basins excess heat during a single assimilation cycle is stored primarily locally within the mixed layer, a simplification of the heat budget that allows us to identify the source of the error as the specified net surface heat flux. Along the equator the increments are primarily confined to thermocline depths indicating the primary source of the error is dominated by heat transport divergence. The error in equatorial heat transport divergence, in turn, can be traced to errors in the strength of the equatorial trade winds. We test our conclusions by introducing modifications of the atmospheric reanalyses based on analysis of ocean temperature analysis increments and repeating the ocean reanalysis experiments using the modified surface fluxes. Comparison of the experiments reveals that the modified fluxes reduce the misfit to ocean observations as well as the differences between the different atmospheric reanalyses.

  4. Functional data analysis on ground reaction force of military load carriage increment

    NASA Astrophysics Data System (ADS)

    Din, Wan Rozita Wan; Rambely, Azmin Sham

    2014-06-01

    Analysis of ground reaction force on military load carriage is done through functional data analysis (FDA) statistical technique. The main objective of the research is to investigate the effect of 10% load increment and to find the maximum suitable load for the Malaysian military. Ten military soldiers age 31 ± 6.2 years, weigh 71.6 ± 10.4 kg and height of 166.3 ± 5.9 cm carrying different military load range from 0% body weight (BW) up to 40% BW participated in an experiment to gather the GRF and kinematic data using Vicon Motion Analysis System, Kirstler force plates and thirty nine body markers. The analysis is conducted in sagittal, medial lateral and anterior posterior planes. The results show that 10% BW load increment has an effect when heel strike and toe-off for all the three planes analyzed with P-value less than 0.001 at 0.05 significant levels. FDA proves to be one of the best statistical techniques in analyzing the functional data. It has the ability to handle filtering, smoothing and curve aligning according to curve features and points of interest.

  5. Dips, ramps, and rolls- Evidence for paleotopographic and syn-depositional fault control on the Western Kentucky No. 4 coal bed, tradewater formation (Bolsovian) Illinois Basin

    USGS Publications Warehouse

    Greb, S.F.; Eble, C.F.; Williams, D.A.; Nelson, W.J.

    2001-01-01

    The Western Kentucky No. 4 coal is a high-volatile B to high-volatile C bituminous coal that has been heavily mined along the southern margin of the Western Kentucky Coal Field. The seam has a reputation for rolling floor elevation. Elongate trends of floor depressions are referred to as "dips" and "rolls" by miners. Some are relatively narrow and straight to slightly curvilinear in plan view, with generally symmetric to slightly asymmetric cross-sections. Others are broader and asymmetric in section, with sharp dips on one limb and gradual, ramp-like dips on the other. Some limbs change laterally from gradual dip, to sharp dip, to offset of the coal. Lateral changes in the rate of floor elevation dip are often associated with changes in coal thickness, and in underground mines, changes in floor elevation are sometimes associated with roof falls and haulage problems. In order to test if coal thickness changes within floor depressions were associated with changes in palynology, petrography and coal quality, the coal was sampled at a surface mine across a broad. ramp-like depression that showed down-dip coal thickening. Increment samples of coal from a thick (150 cm), down-ramp and thinner (127 cm), up-ramp position at one surface mine correlate well between sample sites (a distance of 60 m) except for a single increment. The anomalous increment (31 cm) in the lower-middle part of the thick coal bed contained 20% more Lycospora orbicula spores. The rolling floor elevations noted in the study mines are inferred to have been formed as a result of pre-peat paleotopographic depressions, syn-depositional faulting, fault-controlled pre-peat paleotopography, and from compaction beneath post-depositional channels and slumps. Although the association of thick coal with linear trends and inferred faults has been used in other basins to infer syn-depositional faulting, changes in palynology within increment samples of the seam along a structural ramp in this study provide subtle evidence of faulting within a specific increment of the coal itself. The sudden increase in L. orbicula (produced by Paralycopodites) in a single increment of a down-ramp sample of the Western Kentucky No. 4 coal records the reestablishment of a rheotrophic mire following a sudden change in edaphic conditions. Paralycopodites was a colonizing lycopod, which in this case became locally abundant after the peat was well established along a fault with obvious growth during peat accumulation. Because many coal-mire plants were susceptible to sudden edaphic changes as might accompany faulting or flooding, changes in palynology would be expected in coals affected by syn-depositional faulting. ?? 2001 Elsevier Science B.V. All rights reserved.

  6. SELECTION AND TREATMENT OF STRIPPER GAS WELLS FOR PRODUCTION ENHANCEMENT IN THE MID-CONTINENT

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

    Scott Reeves

    2003-08-01

    Stripper gas wells are an important source of domestic energy supply and under constant threat of permanent loss (shut-in) due to marginal economics. In 1998, 192 thousand stripper gas wells produced over a Tcf of gas, at an average rate of less than 16 Mcfd. This represents about 57% of all producing gas wells in the onshore lower-48 states, yet only 8% of production. Reserves of stripper gas wells are estimated to be only 1.6 Tcf, or slightly over 1% of the onshore lower-48 total (end of year 1996 data). Obviously, stripper gas wells are at the very margin of economic sustenance. As the demand for natural gas in the U.S. grows to the forecasted estimate of over 30 Tcf annually by the year 2010, supply from current conventional sources is expected to decline. Therefore, an important need exists to fully exploit known domestic resources of natural gas, including those represented by stripper gas wells. The overall objectives of this project are to develop an efficient and low-cost methodology to broadly categorize the well performance characteristics for a stripper gas field, identify the high-potential candidate wells for remediation, and diagnose the specific causes for well underperformance. With this capability, stripper gas well operators can more efficiently and economically produce these resources and maximize these gas reserves. A further objective is to identify/develop, evaluate and test ''new and novel,'' economically viable remediation options. Finally, it is the objective of this project that all the methods and technologies developed in this project, while being tested in the Mid-Continent, be widely applicable to stripper gas wells of all types across the country. The project activities during the reporting period were: (1) Compiled information and results of field activities that Oneok has conducted in relation to the project. Field activities have included performing six pressure transient tests, and implementing six workovers, four of which were Gas-Gun treatments. (2) Results indicate that the candidate selection methodology was marginally successful based on the pressure transient test results, but highly successful based on the workovers. For the selected candidate wells that were worked over, incremental reserve costs were $$1.00/Mcf. (3) Based on the combined results, the accuracy of the candidate selection methodology tested under this project is unclear. Generally, however, the technique should provide better-than-average candidate selections.« less

  7. 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 topics, about 80% of the studies revealed that there was no correlation between the two methods. For the correlation quantitative marginal analysis/clinical outcome, data were compared to the clinical outcome of 11 selected clinical studies. In only 2 out of the 11 studies (18%) did the clinical outcome match the prognosis based on the laboratory tests; the remaining studies did not show any correlation. When pooling data on 20 adhesive systems, no correlation was found between the percentage of continuous margin of restorations placed in extracted premolars and the percentage of teeth that showed no retention loss in clinical studies, no discoloured margins, acceptable margins, or absence of secondary caries. With regard to the correlation of dye penetration and clinical studies, no sufficient number of studies was found that matched the inclusion criteria. However, literature data suggest that there is no correlation between microleakage data as measured in the laboratory and clinical parameters. The results of bond strength tests did not correlate with laboratory tests that evaluated the marginal seal of restorations such as microleakage or gap analysis. The quantitative marginal analysis of Class V fillings in the laboratory was unable to predict the performance of the same materials in vivo. Therefore, microleakage tests or the quantitative marginal analysis should be abandoned and research should focus on laboratory tests that are validated with regard to their ability to satisfactorily predict the clinical performance of restorative materials.

  8. Cost-utility analysis of screening for diabetic retinopathy in Japan: a probabilistic Markov modeling study.

    PubMed

    Kawasaki, Ryo; Akune, Yoko; Hiratsuka, Yoshimune; Fukuhara, Shunichi; Yamada, Masakazu

    2015-02-01

    To evaluate the cost-effectiveness for a screening interval longer than 1 year detecting diabetic retinopathy (DR) through the estimation of incremental costs per quality-adjusted life year (QALY) based on the best available clinical data in Japan. A Markov model with a probabilistic cohort analysis was framed to calculate incremental costs per QALY gained by implementing a screening program detecting DR in Japan. A 1-year cycle length and population size of 50,000 with a 50-year time horizon (age 40-90 years) was used. Best available clinical data from publications and national surveillance data was used, and a model was designed including current diagnosis and management of DR with corresponding visual outcomes. One-way and probabilistic sensitivity analyses were performed considering uncertainties in the parameters. In the base-case analysis, the strategy with a screening program resulted in an incremental cost of 5,147 Japanese yen (¥; US$64.6) and incremental effectiveness of 0.0054 QALYs per person screened. The incremental cost-effectiveness ratio was ¥944,981 (US$11,857) per QALY. The simulation suggested that screening would result in a significant reduction in blindness in people aged 40 years or over (-16%). Sensitivity analyses suggested that in order to achieve both reductions in blindness and cost-effectiveness in Japan, the screening program should screen those aged 53-84 years, at intervals of 3 years or less. An eye screening program in Japan would be cost-effective in detecting DR and preventing blindness from DR, even allowing for the uncertainties in estimates of costs, utility, and current management of DR.

  9. [A new technique for ensuring negative surgical margins during partial nephrectomy: the ex vivo ultrasound control].

    PubMed

    Desmonts, A; Tillou, X; Le Gal, S; Secco, M; Orczyk, C; Bensadoun, H; Doerfler, A

    2013-10-01

    To evaluate the feasibility and the efficiency of intraoperative ex vivo ultrasound of resection margins in patients undergoing partial nephrectomy by urologist. Patients undergoing partial nephrectomy from July 2010 to November 2012 for T1-T2 renal tumors were included in analysis. Tumor margin status was immediately determined by ex vivo ultrasound done by the surgeon himself. Results were compared with margin status on definitive pathological evaluation. A total of 26 men and 15 women with a median age of 61 (30-82) years old were included in analysis. Intraoperative ex vivo ultrasound revealed negative surgical margins in 38 cases and positive margins in two. Final pathological results revealed negative margins in all except one case. Ultrasound sensitivity and specificity were 100% and 97%, respectively. Mean ultrasound duration was 1minute±1. Mean tumor and margin sizes were 3.4±1.8cm and 2.38±1.76mm, respectively. Intraoperative ex vivo ultrasound of resection margins in patients undergoing partial nephrectomy by a urologist seemed to be feasible, efficient and easy. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  10. Meta-analysis of studies with bivariate binary outcomes: a marginal beta-binomial model approach

    PubMed Central

    Chen, Yong; Hong, Chuan; Ning, Yang; Su, Xiao

    2018-01-01

    When conducting a meta-analysis of studies with bivariate binary outcomes, challenges arise when the within-study correlation and between-study heterogeneity should be taken into account. In this paper, we propose a marginal beta-binomial model for the meta-analysis of studies with binary outcomes. This model is based on the composite likelihood approach, and has several attractive features compared to the existing models such as bivariate generalized linear mixed model (Chu and Cole, 2006) and Sarmanov beta-binomial model (Chen et al., 2012). The advantages of the proposed marginal model include modeling the probabilities in the original scale, not requiring any transformation of probabilities or any link function, having closed-form expression of likelihood function, and no constraints on the correlation parameter. More importantly, since the marginal beta-binomial model is only based on the marginal distributions, it does not suffer from potential misspecification of the joint distribution of bivariate study-specific probabilities. Such misspecification is difficult to detect and can lead to biased inference using currents methods. We compare the performance of the marginal beta-binomial model with the bivariate generalized linear mixed model and the Sarmanov beta-binomial model by simulation studies. Interestingly, the results show that the marginal beta-binomial model performs better than the Sarmanov beta-binomial model, whether or not the true model is Sarmanov beta-binomial, and the marginal beta-binomial model is more robust than the bivariate generalized linear mixed model under model misspecifications. Two meta-analyses of diagnostic accuracy studies and a meta-analysis of case-control studies are conducted for illustration. PMID:26303591

  11. Clinical and semiquantitative marginal analysis of four tooth-coloured inlay systems at 3 years.

    PubMed

    Gladys, S; Van Meerbeek, B; Inokoshi, S; Willems, G; Braem, M; Lambrechts, P; Vanherle, G

    1995-12-01

    The marginal quality of four tooth-coloured inlay systems was clinically investigated and subjected to computer-aided semiquantitative marginal analysis under scanning electron microscopy (SEM) after 3 years of clinical service. Three of the restoration types were made using the Cerec CAD-CAM apparatus: one was milled from preformed glass ceramic blocks, and the two other inlay types were milled from preformed porcelain blocks. The fourth system was based on an experimental indirect resin composite inlay system. Each inlay type was luted with a different luting resin composite. The clinical evaluation was performed with a mirror and explorer by two clinicians separately, and the marginal analysis was conducted microscopically on replicas (SEM x 200). After 3 years in situ, all the restorations were clinically acceptable. No recurrent caries was observed. Marginal analysis under SEM detected a high percentage of submargination for all four systems, which suggests that their respective resin composite luting agents were all subject to wear. The percentage of marginal fractures on the enamel side as well as on the inlay side did not increase dramatically compared to the 6-month results. The first recall after 6 months of clinical service indicated how tooth-coloured inlays behave at their margins. The 3-year results confirmed the early findings, indicating that wear of resin composite lutes is important and present in all systems. The two ceramic materials showed a similar behaviour at the margins. The resin composite inlay performed better at the inlay site than at the enamel site.

  12. [Economic impact of nosocomial bacteraemia. A comparison of three calculation methods].

    PubMed

    Riu, Marta; Chiarello, Pietro; Terradas, Roser; Sala, Maria; Castells, Xavier; Knobel, Hernando; Cots, Francesc

    2016-12-01

    The excess cost associated with nosocomial bacteraemia (NB) is used as a measurement of the impact of these infections. However, some authors have suggested that traditional methods overestimate the incremental cost due to the presence of various types of bias. The aim of this study was to compare three assessment methods of NB incremental cost to correct biases in previous analyses. Patients who experienced an episode of NB between 2005 and 2007 were compared with patients grouped within the same All Patient Refined-Diagnosis-Related Group (APR-DRG) without NB. The causative organisms were grouped according to the Gram stain, and whether bacteraemia was caused by a single or multiple microorganisms, or by a fungus. Three assessment methods are compared: stratification by disease; econometric multivariate adjustment using a generalised linear model (GLM); and propensity score matching (PSM) was performed to control for biases in the econometric model. The analysis included 640 admissions with NB and 28,459 without NB. The observed mean cost was €24,515 for admissions with NB and €4,851.6 for controls (without NB). Mean incremental cost was estimated at €14,735 in stratified analysis. Gram positive microorganism had the lowest mean incremental cost, €10,051. In the GLM, mean incremental cost was estimated as €20,922, and adjusting with PSM, the mean incremental cost was €11,916. The three estimates showed important differences between groups of microorganisms. Using enhanced methodologies improves the adjustment in this type of study and increases the value of the results. Copyright © 2015 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosas y Microbiología Clínica. All rights reserved.

  13. 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

  14. High-resolution sclerochronological analysis of the bivalve mollusk Saxidomus gigantea from Alaska and British Columbia: techniques for revealing environmental archives and archaeological seasonality

    USGS Publications Warehouse

    Hallman, Nadine; Burchell, Meghan; Schone, Bernd R.; Irvine, Gail V.; Maxwell, David

    2009-01-01

    The butter clam, Saxidomus gigantea, is one of the most commonly recovered bivalves from archaeological shell middens on the Pacific Coast of North America. This study presents the results of the sclerochronology of modern specimens of S. gigantea, collected monthly from Pender Island (British Columbia), and additional modern specimens from the Dundas Islands (BC) and Mink and Little Takli Islands (Alaska). The methods presented can be used as a template to interpret local environmental conditions and increase the precision of seasonality estimates in shellfish using sclerochronology and oxygen isotope analysis. This method can also identify, with a high degree of accuracy, the date of shell collection to the nearest fortnightly cycle, the time of day the shell was collected and the approximate tidal elevation (i.e., approx. water depth and distance from the shoreline) from which the shell was collected. Life-history traits of S. gigantea were analyzed to understand the timing of growth line formation, the duration of the growing season, the growth rate, and the reliability of annual increments. We also examine the influence of the tidal regime and freshwater mixing in estuarine locations and how these variables can affect both incremental structures and oxygen isotope values. The results of the sclerochronological analysis show that there is a latitudinal trend in shell growth that needs to be considered when using shells for seasonality studies. Oxygen isotope analysis reveals clear annual cycles with the most positive values corresponding to the annual winter growth lines, and the most negative values corresponding to high temperatures during the summer. Intra-annual increment widths demonstrate clear seasonal oscillations with broadest increments in summer and very narrow increments or no growth during the winter months. This study provides new insights into the biology, geochemistry and seasonal growth of S. gigantea, which are crucial for paleoclimate reconstructions and interpreting seasonality patterns of past human collection.

  15. Are financial incentives cost-effective to support smoking cessation during pregnancy?

    PubMed

    Boyd, Kathleen A; Briggs, Andrew H; Bauld, Linda; Sinclair, Lesley; Tappin, David

    2016-02-01

    To investigate the cost-effectiveness of up to £400 worth of financial incentives for smoking cessation in pregnancy as an adjunct to routine health care. Cost-effectiveness analysis based on a Phase II randomized controlled trial (RCT) and a cost-utility analysis using a life-time Markov model. The RCT was undertaken in Glasgow, Scotland. The economic analysis was undertaken from the UK National Health Service (NHS) perspective. A total of 612 pregnant women randomized to receive usual cessation support plus or minus financial incentives of up to £400 vouchers (US $609), contingent upon smoking cessation. Comparison of usual support and incentive interventions in terms of cotinine-validated quitters, quality-adjusted life years (QALYs) and direct costs to the NHS. The incremental cost per quitter at 34-38 weeks pregnant was £1127 ($1716).This is similar to the standard look-up value derived from Stapleton & West's published ICER tables, £1390 per quitter, by looking up the Cessation in Pregnancy Incentives Trial (CIPT) incremental cost (£157) and incremental 6-month quit outcome (0.14). The life-time model resulted in an incremental cost of £17 [95% confidence interval (CI) = -£93, £107] and a gain of 0.04 QALYs (95% CI = -0.058, 0.145), giving an ICER of £482/QALY ($734/QALY). Probabilistic sensitivity analysis indicates uncertainty in these results, particularly regarding relapse after birth. The expected value of perfect information was £30 million (at a willingness to pay of £30 000/QALY), so given current uncertainty, additional research is potentially worthwhile. Financial incentives for smoking cessation in pregnancy are highly cost-effective, with an incremental cost per quality-adjusted life years of £482, which is well below recommended decision thresholds. © 2015 Society for the Study of Addiction.

  16. Heart failure disease management programs: a cost-effectiveness analysis.

    PubMed

    Chan, David C; Heidenreich, Paul A; Weinstein, Milton C; Fonarow, Gregg C

    2008-02-01

    Heart failure (HF) disease management programs have shown impressive reductions in hospitalizations and mortality, but in studies limited to short time frames and high-risk patient populations. Current guidelines thus only recommend disease management targeted to high-risk patients with HF. This study applied a new technique to infer the degree to which clinical trials have targeted patients by risk based on observed rates of hospitalization and death. A Markov model was used to assess the incremental life expectancy and cost of providing disease management for high-risk to low-risk patients. Sensitivity analyses of various long-term scenarios and of reduced effectiveness in low-risk patients were also considered. The incremental cost-effectiveness ratio of extending coverage to all patients was $9700 per life-year gained in the base case. In aggregate, universal coverage almost quadrupled life-years saved as compared to coverage of only the highest quintile of risk. A worst case analysis with simultaneous conservative assumptions yielded an incremental cost-effectiveness ratio of $110,000 per life-year gained. In a probabilistic sensitivity analysis, 99.74% of possible incremental cost-effectiveness ratios were <$50,000 per life-year gained. Heart failure disease management programs are likely cost-effective in the long-term along the whole spectrum of patient risk. Health gains could be extended by enrolling a broader group of patients with HF in disease management.

  17. Methodology for Sensitivity Analysis, Approximate Analysis, and Design Optimization in CFD for Multidisciplinary Applications

    NASA Technical Reports Server (NTRS)

    Taylor, Arthur C., III; Hou, Gene W.

    1996-01-01

    An incremental iterative formulation together with the well-known spatially split approximate-factorization algorithm, is presented for solving the large, sparse systems of linear equations that are associated with aerodynamic sensitivity analysis. This formulation is also known as the 'delta' or 'correction' form. For the smaller two dimensional problems, a direct method can be applied to solve these linear equations in either the standard or the incremental form, in which case the two are equivalent. However, iterative methods are needed for larger two-dimensional and three dimensional applications because direct methods require more computer memory than is currently available. Iterative methods for solving these equations in the standard form are generally unsatisfactory due to an ill-conditioned coefficient matrix; this problem is overcome when these equations are cast in the incremental form. The methodology is successfully implemented and tested using an upwind cell-centered finite-volume formulation applied in two dimensions to the thin-layer Navier-Stokes equations for external flow over an airfoil. In three dimensions this methodology is demonstrated with a marching-solution algorithm for the Euler equations to calculate supersonic flow over the High-Speed Civil Transport configuration (HSCT 24E). The sensitivity derivatives obtained with the incremental iterative method from a marching Euler code are used in a design-improvement study of the HSCT configuration that involves thickness. camber, and planform design variables.

  18. FRED: a program development tool

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

    Shilling, J.

    1985-09-01

    The structured, screen-based editor FRED is introduced. FRED provides incremental parsing and semantic analysis. The parsing is based on an LL(1) top-down algorithm which has been modified to provide follow-the-cursor parsing and soft templates. The languages accepted by the editor are LL(1) languages with the addition of the Unknown and preferred production non-terminal classes. The semantic analysis is based on the incremental update of attribute grammar equations. We briefly describe the interface between FRED and an automated reference librarian system that is under development.

  19. Atmospheric response to Saharan dust deduced from ECMWF reanalysis increments

    NASA Astrophysics Data System (ADS)

    Kishcha, P.; Alpert, P.; Barkan, J.; Kirchner, I.; Machenhauer, B.

    2003-04-01

    This study focuses on the atmospheric temperature response to dust deduced from a new source of data - the European Reanalysis (ERA) increments. These increments are the systematic errors of global climate models, generated in reanalysis procedure. The model errors result not only from the lack of desert dust but also from a complex combination of many kinds of model errors. Over the Sahara desert the dust radiative effect is believed to be a predominant model defect which should significantly affect the increments. This dust effect was examined by considering correlation between the increments and remotely-sensed dust. Comparisons were made between April temporal variations of the ERA analysis increments and the variations of the Total Ozone Mapping Spectrometer aerosol index (AI) between 1979 and 1993. The distinctive structure was identified in the distribution of correlation composed of three nested areas with high positive correlation (> 0.5), low correlation, and high negative correlation (<-0.5). The innermost positive correlation area (PCA) is a large area near the center of the Sahara desert. For some local maxima inside this area the correlation even exceeds 0.8. The outermost negative correlation area (NCA) is not uniform. It consists of some areas over the eastern and western parts of North Africa with a relatively small amount of dust. Inside those areas both positive and negative high correlations exist at pressure levels ranging from 850 to 700 hPa, with the peak values near 775 hPa. Dust-forced heating (cooling) inside the PCA (NCA) is accompanied by changes in the static stability of the atmosphere above the dust layer. The reanalysis data of the European Center for Medium Range Weather Forecast(ECMWF) suggests that the PCA (NCA) corresponds mainly to anticyclonic (cyclonic) flow, negative (positive) vorticity, and downward (upward) airflow. These facts indicate an interaction between dust-forced heating /cooling and atmospheric circulation. The April correlation results are supported by the analysis of vertical distribution of dust concentration, derived from the 24-hour dust prediction system at Tel Aviv University (website: http://earth.nasa.proj.ac.il/dust/current/). For other months the analysis is more complicated because of the essential increasing of humidity along with the northward progress of the ITCZ and the significant impact on the increments.

  20. A hierarchical structure for automatic meshing and adaptive FEM analysis

    NASA Technical Reports Server (NTRS)

    Kela, Ajay; Saxena, Mukul; Perucchio, Renato

    1987-01-01

    A new algorithm for generating automatically, from solid models of mechanical parts, finite element meshes that are organized as spatially addressable quaternary trees (for 2-D work) or octal trees (for 3-D work) is discussed. Because such meshes are inherently hierarchical as well as spatially addressable, they permit efficient substructuring techniques to be used for both global analysis and incremental remeshing and reanalysis. The global and incremental techniques are summarized and some results from an experimental closed loop 2-D system in which meshing, analysis, error evaluation, and remeshing and reanalysis are done automatically and adaptively are presented. The implementation of 3-D work is briefly discussed.

  1. Discriminant and Incremental Validity of Self-Concept and Academic Self-Efficacy: A Meta-Analysis

    ERIC Educational Resources Information Center

    Huang, Chiungjung

    2012-01-01

    Two studies examined the discriminant and incremental validity of self-concept and academic self-efficacy. Study 1, which meta-analysed 64 studies comprising 74 independent samples (N = 24,773), found a strong mean correlation of 0.43 between self-concept and academic self-efficacy. The domains of self-concept and self-efficacy, and the domain…

  2. Exploiting Outage and Error Probability of Cooperative Incremental Relaying in Underwater Wireless Sensor Networks

    PubMed Central

    Nasir, Hina; Javaid, Nadeem; Sher, Muhammad; Qasim, Umar; Khan, Zahoor Ali; Alrajeh, Nabil; Niaz, Iftikhar Azim

    2016-01-01

    This paper embeds a bi-fold contribution for Underwater Wireless Sensor Networks (UWSNs); performance analysis of incremental relaying in terms of outage and error probability, and based on the analysis proposition of two new cooperative routing protocols. Subject to the first contribution, a three step procedure is carried out; a system model is presented, the number of available relays are determined, and based on cooperative incremental retransmission methodology, closed-form expressions for outage and error probability are derived. Subject to the second contribution, Adaptive Cooperation in Energy (ACE) efficient depth based routing and Enhanced-ACE (E-ACE) are presented. In the proposed model, feedback mechanism indicates success or failure of data transmission. If direct transmission is successful, there is no need for relaying by cooperative relay nodes. In case of failure, all the available relays retransmit the data one by one till the desired signal quality is achieved at destination. Simulation results show that the ACE and E-ACE significantly improves network performance, i.e., throughput, when compared with other incremental relaying protocols like Cooperative Automatic Repeat reQuest (CARQ). E-ACE and ACE achieve 69% and 63% more throughput respectively as compared to CARQ in hard underwater environment. PMID:27420061

  3. Tissue preservation with mass spectroscopic analysis: Implications for cancer diagnostics.

    PubMed

    Hall, O Morgan; Peer, Cody J; Figg, William D

    2018-05-17

    Surgical intervention is a common treatment modality for localized cancer. Post-operative analysis involves evaluation of surgical margins to assess whether all malignant tissue has been resected because positive surgical margins lead to a greater likelihood of recurrence. Secondary treatments are utilized to minimize the negative effects of positive surgical margins. Recently, in Science Translational Medicine, Zhang et al describe a new mass spectroscopic technique that could potentially decrease the likelihood of positive surgical margins. Their nondestructive in vivo tissue sampling leads to a highly accurate and rapid cancer diagnosis with great precision between healthy and malignant tissue. This new tool has the potential to improve surgical margins and accelerate cancer diagnostics by analyzing biomolecular signatures of various tissues and diseases.

  4. Systems Engineering and Integration (SE and I)

    NASA Technical Reports Server (NTRS)

    Chevers, ED; Haley, Sam

    1990-01-01

    The issue of technology advancement and future space transportation vehicles is addressed. The challenge is to develop systems which can be evolved and improved in small incremental steps where each increment reduces present cost, improves, reliability, or does neither but sets the stage for a second incremental upgrade that does. Future requirements are interface standards for commercial off the shelf products to aid in the development of integrated facilities; enhanced automated code generation system slightly coupled to specification and design documentation; modeling tools that support data flow analysis; and shared project data bases consisting of technical characteristics cast information, measurement parameters, and reusable software programs. Topics addressed include: advanced avionics development strategy; risk analysis and management; tool quality management; low cost avionics; cost estimation and benefits; computer aided software engineering; computer systems and software safety; system testability; and advanced avionics laboratories - and rapid prototyping. This presentation is represented by viewgraphs only.

  5. Read margin analysis of crossbar arrays using the cell-variability-aware simulation method

    NASA Astrophysics Data System (ADS)

    Sun, Wookyung; Choi, Sujin; Shin, Hyungsoon

    2018-02-01

    This paper proposes a new concept of read margin analysis of crossbar arrays using cell-variability-aware simulation. The size of the crossbar array should be considered to predict the read margin characteristic of the crossbar array because the read margin depends on the number of word lines and bit lines. However, an excessively high-CPU time is required to simulate large arrays using a commercial circuit simulator. A variability-aware MATLAB simulator that considers independent variability sources is developed to analyze the characteristics of the read margin according to the array size. The developed MATLAB simulator provides an effective method for reducing the simulation time while maintaining the accuracy of the read margin estimation in the crossbar array. The simulation is also highly efficient in analyzing the characteristic of the crossbar memory array considering the statistical variations in the cell characteristics.

  6. Tree litter and forest understorey vegetation: a conceptual framework to understand the effects of tree litter on a perennial geophyte, Anemone nemorosa.

    PubMed

    Baltzinger, Marie; Archaux, Frédéric; Dumas, Yann

    2012-05-01

    Litter is a key factor in structuring plant populations, through positive or negative interactions. The litter layer forms a mechanical barrier that is often strongly selective against individuals lacking hypocotyle plasticity. Litter composition also interacts with plant growth by providing beneficial nutrients or, inversely, by allowing harmful allelopathic leaching. As conspicuous litter fall accumulation is often observed under deciduous forests, interactions between tree litter and understorey plant populations are worthy of study. In a 1-year ex-situ experiment, the effects of tree litter on the growth of Anemone nemorosa, a small perennial forest geophyte, were investigated. Three 'litter quantity' treatments were defined, representative of forest floor litter (199, 356·5 and 514 g m(-2)), which were crossed with five 'litter composition' treatments (Quercus petraea, Fagus sylvatica, Carpinus betulus, Q. petraea + F. sylvatica and Q. petraea + C. betulus), plus a no-litter control. Path analysis was then used to investigate the pathways linking litter characteristics and components of adult plant growth. As expected, the heavier the litter, the longer the petiole; rhizome growth, however, was not depreciated by the litter-induced petiole lengthening. Both rhizome mass increment and number of initiated buds marginally increased with the amount of litter. Rhizome mass increment was in fact determined primarily by leaf area and leaf life span, neither of which was unequivocally correlated with any litter characteristics. However, the presence of litter significantly increased leafing success: following a late frost event, control rhizomes growing in the absence of litter experienced higher leaf mortality before leaf unfolding. The study questions the role of litter as a physical or chemical barrier to ground vegetation; to better understand this role, there is a need for ex-situ, longer-term experiments coupled with in-situ observations in the forest.

  7. Tree litter and forest understorey vegetation: a conceptual framework to understand the effects of tree litter on a perennial geophyte, Anemone nemorosa

    PubMed Central

    Baltzinger, Marie; Archaux, Frédéric; Dumas, Yann

    2012-01-01

    Background and Aims Litter is a key factor in structuring plant populations, through positive or negative interactions. The litter layer forms a mechanical barrier that is often strongly selective against individuals lacking hypocotyle plasticity. Litter composition also interacts with plant growth by providing beneficial nutrients or, inversely, by allowing harmful allelopathic leaching. As conspicuous litter fall accumulation is often observed under deciduous forests, interactions between tree litter and understorey plant populations are worthy of study. Methods In a 1-year ex-situ experiment, the effects of tree litter on the growth of Anemone nemorosa, a small perennial forest geophyte, were investigated. Three ‘litter quantity’ treatments were defined, representative of forest floor litter (199, 356·5 and 514 g m−2), which were crossed with five ‘litter composition’ treatments (Quercus petraea, Fagus sylvatica, Carpinus betulus, Q. petraea + F. sylvatica and Q. petraea + C. betulus), plus a no-litter control. Path analysis was then used to investigate the pathways linking litter characteristics and components of adult plant growth. Key Results As expected, the heavier the litter, the longer the petiole; rhizome growth, however, was not depreciated by the litter-induced petiole lengthening. Both rhizome mass increment and number of initiated buds marginally increased with the amount of litter. Rhizome mass increment was in fact determined primarily by leaf area and leaf life span, neither of which was unequivocally correlated with any litter characteristics. However, the presence of litter significantly increased leafing success: following a late frost event, control rhizomes growing in the absence of litter experienced higher leaf mortality before leaf unfolding. Conclusions The study questions the role of litter as a physical or chemical barrier to ground vegetation; to better understand this role, there is a need for ex-situ, longer-term experiments coupled with in-situ observations in the forest. PMID:22419760

  8. Cost-Effectiveness of Surgery, Stereotactic Body Radiation Therapy, and Systemic Therapy for Pulmonary Oligometastases

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

    Lester-Coll, Nataniel H., E-mail: nataniel.lester-coll@yale.edu; Rutter, Charles E.; Bledsoe, Trevor J.

    Introduction: Pulmonary oligometastases have conventionally been managed with surgery and/or systemic therapy. However, given concerns about the high cost of systemic therapy and improvements in local treatment of metastatic cancer, the optimal cost-effective management of these patients is unclear. Therefore, we sought to assess the cost-effectiveness of initial management strategies for pulmonary oligometastases. Methods and Materials: A cost-effectiveness analysis using a Markov modeling approach was used to compare average cumulative costs, quality adjusted life years (QALYs), and incremental cost-effectiveness ratios (ICERs) among 3 initial disease management strategies: video-assisted thoracic surgery (VATS) wedge resection, stereotactic body radiation therapy (SBRT), and systemicmore » therapy among 5 different cohorts of patient disease: (1) melanoma; (2) non-small cell lung cancer adenocarcinoma without an EGFR mutation (NSCLC AC); (3) NSCLC with an EGFR mutation (NSCLC EGFRm AC); (4) NSCLC squamous cell carcinoma (NSCLC SCC); and (5) colon cancer. One-way sensitivity analyses and probabilistic sensitivity analyses were performed to analyze uncertainty with regard to model parameters. Results: In the base case, SBRT was cost effective for melanoma, with costs/net QALYs of $467,787/0.85. In patients with NSCLC, the most cost-effective strategies were SBRT for AC ($156,725/0.80), paclitaxel/carboplatin for SCC ($123,799/0.48), and erlotinib for EGFRm AC ($147,091/1.90). Stereotactic body radiation therapy was marginally cost-effective for EGFRm AC compared to erlotinib with an incremental cost-effectiveness ratio of $126,303/QALY. For colon cancer, VATS wedge resection ($147,730/2.14) was the most cost-effective strategy. Variables with the greatest influence in the model were erlotinib-associated progression-free survival (EGFRm AC), toxicity (EGFRm AC), cost of SBRT (NSCLC SCC), and patient utilities (all histologies). Conclusions: Video-assisted thoracic surgery wedge resection or SBRT can be cost-effective in select patients with pulmonary oligometastases, depending on histology, efficacy, and tolerability of treatment and patient preferences.« less

  9. Implications of resin-based composite (RBC) restoration on cuspal deflection and microleakage score in molar teeth: Placement protocol and restorative material.

    PubMed

    McHugh, Lauren E J; Politi, Ioanna; Al-Fodeh, Rami S; Fleming, Garry J P

    2017-09-01

    To assess the cuspal deflection of standardised large mesio-occluso-distal (MOD) cavities in third molar teeth restored using conventional resin-based composite (RBC) or their bulk fill restorative counterparts compared with the unbound condition using a twin channel deflection measuring gauge. Following thermocycling, the cervical microleakage of the restored teeth was assessed to determine marginal integrity. Standardised MOD cavities were prepared in forty-eight sound third molar teeth and randomly allocated to six groups. Restorations were placed in conjunction with (and without) a universal bonding system and resin restorative materials were irradiated with a light-emitting-diode light-curing-unit. The dependent variable was the restoration protocol, eight oblique increments for conventional RBCs or two horizontal increments for the bulk fill resin restoratives. The cumulative buccal and palatal cuspal deflections from a twin channel deflection measuring gauge were summed, the restored teeth thermally fatigued, immersed in 0.2% basic fuchsin dye for 24h, sectioned and examined for cervical microleakage score. The one-way analysis of variance (ANOVA) identified third molar teeth restored using conventional RBC materials had significantly higher mean total cuspal deflection values compared with bulk fill resin restorative restoration (all p<0.0001). For the conventional RBCs, Admira Fusion (bonded) third molar teeth had significantly the lowest microleakage scores (all p<0.001) while the Admira Fusion x-tra (bonded) bulk fill resin restored teeth had significantly the lowest microleakage scores compared with Tetric EvoCeram Bulk Fill (bonded and non-bonded) teeth (all p<0.001). Not all conventional RBCs or bulk fill resin restoratives behave in a similar manner when used to restore standardised MOD cavities in third molar teeth. It would appear that light irradiation of individual conventional RBCs or bulk fill resin restoratives may be problematic such that material selection is vital in the absence of clinical data. Copyright © 2017 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  10. Evaluation of margins in head and neck squamous cell carcinoma from the surgeon's perspective.

    PubMed

    Baumeister, Philipp; Baumüller, Konstantin; Harréus, Ulrich; Reiter, Maximilian; Welz, Christian

    2018-05-01

    The surgeon's evaluation of resection status based on frozen section analysis during operation and pathological examination of resected specimens often differ. For this study, we recapitulated the surgeon's perspective during an operation, accordingly classified the evaluation of margins by the surgeon, and analyzed its impact on the outcome compared with the pathological results. This was a retrospective analysis. As data sources, paper-based and digital patient files, as well as the Munich Cancer Registry database were used. Three hundred ninety-six cases were included in this analysis. Only the evaluation of margins by the surgeon influenced local control, and the pathological results influenced disease-free survival (DFS). Surprisingly, margins of >5 mm of normal tissue to cancer growth led to local control and overall survival (OS) significantly worse than 1 to 5-mm resections. The evaluation of margins by the surgeon is of significant importance for local control and OS. It is largely based on frozen section analysis, which, therefore, should be used whenever possible. © 2018 Wiley Periodicals, Inc.

  11. A new universal simplified adhesive: 36-Month randomized double-blind clinical trial.

    PubMed

    Loguercio, Alessandro D; de Paula, Eloisa Andrade; Hass, Viviane; Luque-Martinez, Issis; Reis, Alessandra; Perdigão, Jorge

    2015-09-01

    It is still debatable which technique should be used with universal adhesives, either etch-and-rinse (wet or dry) or self-etch strategy (with or without selective enamel etching). To evaluate the 36-month clinical performance of Scotchbond Universal Adhesive (SU, 3M ESPE) in non-carious cervical lesions (NCCLs) using two evaluation criteria. Thirty-nine patients participated in this study. Two-hundred restorations were assigned to four groups: ERm: etch-and-rinse+moist dentin; ERd: etch-and-rinse+dry dentin; Set: selective enamel etching; and SE: self-etch. The same composite resin was inserted for all restorations in up to 3 increments. The restorations were evaluated at baseline and at 6-, 18-, and 36-months using both the FDI and the USPHS criteria. Statistical analyses were performed with Friedman repeated measures ANOVA by rank and McNemar test for significance in each pair (α=0.05). Eight restorations (ERm: 1; ERd: 1; Set: 1 and SE: 5) were lost after 36 months, but only significant for SE when compared with baseline (p=0.02 for either criteria). Marginal staining occurred in 6.8% of the restorations (groups ERm, ERd, and Set) and 17.5% of the restorations (group SE), with significant difference for each group when compared with baseline using the FDI criteria (p<0.04), while statistical significance was reached only for SE when compared with baseline using the USPHS criteria (p<0.03). Twenty-eight and 49 restorations were scored as bravo for marginal adaptation using the USPHS and FDI criteria, respectively, with significant difference for each group when compared with baseline (p<0.05). While there was no statistical difference among bonding strategies when a universal adhesive was used, there were signs of degradation when the universal adhesive was applied in SE mode. The FDI criteria remain more sensitive than the USPHS criteria, especially for the criteria marginal staining and marginal adaptation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Multi-Reanalysis Comparison of Variability in Analysis Increment of Column-Integrated Water Vapor Associated with Madden-Julian Oscillation

    NASA Astrophysics Data System (ADS)

    Yokoi, S.

    2014-12-01

    This study conducts a comparison of three reanalysis products (JRA-55, JRA-25, and ERA-Interim) in representation of Madden-Julian Oscillation (MJO), focusing on column-integrated water vapor (CWV) that is considered as an essential variable for discussing MJO dynamics. Besides the analysis fields of CWV, which exhibit spatio-temporal distributions that are quite similar to satellite observations, CWV tendency simulated by forecast models and analysis increment calculated by data assimilation are examined. For JRA-55, it is revealed that, while its forecast model is able to simulate eastward propagation of the CWV anomaly, it tends to weaken the amplitude, and data assimilation process sustains the amplitude. The multi-reanalysis comparison of the analysis increment further reveals that this weakening bias is probably caused by excessively weak cloud-radiative feedback represented by the model. This bias in the feedback strength makes anomalous moisture supply by the vertical advection term in the CWV budget equation too insensitive to precipitation anomaly, resulting in reduction of the amplitude of CWV anomaly. ERA-Interim has a nearly opposite feature; the forecast model represents excessively strong feedback and unrealistically strengthens the amplitude, while the data assimilation weakens it. These results imply the necessity of accurate representation of the cloud-radiative feedback strength for a short-term MJO forecast, and may be evidence to support the argument that this feedback is essential for the existence of MJO. Furthermore, this study demonstrates that the multi-reanalysis comparison of the analysis increment will provide useful information for identifying model biases and, potentially, for estimating parameters that are difficult to estimate solely from observation data, such as gross moist stability.

  13. On the Accuracy and Parallelism of GPGPU-Powered Incremental Clustering Algorithms

    PubMed Central

    He, Li; Zheng, Hao; Wang, Lei

    2017-01-01

    Incremental clustering algorithms play a vital role in various applications such as massive data analysis and real-time data processing. Typical application scenarios of incremental clustering raise high demand on computing power of the hardware platform. Parallel computing is a common solution to meet this demand. Moreover, General Purpose Graphic Processing Unit (GPGPU) is a promising parallel computing device. Nevertheless, the incremental clustering algorithm is facing a dilemma between clustering accuracy and parallelism when they are powered by GPGPU. We formally analyzed the cause of this dilemma. First, we formalized concepts relevant to incremental clustering like evolving granularity. Second, we formally proved two theorems. The first theorem proves the relation between clustering accuracy and evolving granularity. Additionally, this theorem analyzes the upper and lower bounds of different-to-same mis-affiliation. Fewer occurrences of such mis-affiliation mean higher accuracy. The second theorem reveals the relation between parallelism and evolving granularity. Smaller work-depth means superior parallelism. Through the proofs, we conclude that accuracy of an incremental clustering algorithm is negatively related to evolving granularity while parallelism is positively related to the granularity. Thus the contradictory relations cause the dilemma. Finally, we validated the relations through a demo algorithm. Experiment results verified theoretical conclusions. PMID:29123546

  14. Incremental k-core decomposition: Algorithms and evaluation

    DOE PAGES

    Sariyuce, Ahmet Erdem; Gedik, Bugra; Jacques-SIlva, Gabriela; ...

    2016-02-01

    A k-core of a graph is a maximal connected subgraph in which every vertex is connected to at least k vertices in the subgraph. k-core decomposition is often used in large-scale network analysis, such as community detection, protein function prediction, visualization, and solving NP-hard problems on real networks efficiently, like maximal clique finding. In many real-world applications, networks change over time. As a result, it is essential to develop efficient incremental algorithms for dynamic graph data. In this paper, we propose a suite of incremental k-core decomposition algorithms for dynamic graph data. These algorithms locate a small subgraph that ismore » guaranteed to contain the list of vertices whose maximum k-core values have changed and efficiently process this subgraph to update the k-core decomposition. We present incremental algorithms for both insertion and deletion operations, and propose auxiliary vertex state maintenance techniques that can further accelerate these operations. Our results show a significant reduction in runtime compared to non-incremental alternatives. We illustrate the efficiency of our algorithms on different types of real and synthetic graphs, at varying scales. Furthermore, for a graph of 16 million vertices, we observe relative throughputs reaching a million times, relative to the non-incremental algorithms.« less

  15. Meta-analysis of studies with bivariate binary outcomes: a marginal beta-binomial model approach.

    PubMed

    Chen, Yong; Hong, Chuan; Ning, Yang; Su, Xiao

    2016-01-15

    When conducting a meta-analysis of studies with bivariate binary outcomes, challenges arise when the within-study correlation and between-study heterogeneity should be taken into account. In this paper, we propose a marginal beta-binomial model for the meta-analysis of studies with binary outcomes. This model is based on the composite likelihood approach and has several attractive features compared with the existing models such as bivariate generalized linear mixed model (Chu and Cole, 2006) and Sarmanov beta-binomial model (Chen et al., 2012). The advantages of the proposed marginal model include modeling the probabilities in the original scale, not requiring any transformation of probabilities or any link function, having closed-form expression of likelihood function, and no constraints on the correlation parameter. More importantly, because the marginal beta-binomial model is only based on the marginal distributions, it does not suffer from potential misspecification of the joint distribution of bivariate study-specific probabilities. Such misspecification is difficult to detect and can lead to biased inference using currents methods. We compare the performance of the marginal beta-binomial model with the bivariate generalized linear mixed model and the Sarmanov beta-binomial model by simulation studies. Interestingly, the results show that the marginal beta-binomial model performs better than the Sarmanov beta-binomial model, whether or not the true model is Sarmanov beta-binomial, and the marginal beta-binomial model is more robust than the bivariate generalized linear mixed model under model misspecifications. Two meta-analyses of diagnostic accuracy studies and a meta-analysis of case-control studies are conducted for illustration. Copyright © 2015 John Wiley & Sons, Ltd.

  16. Predicting success of methotrexate treatment by pretreatment HCG level and 24-hour HCG increment.

    PubMed

    Levin, Gabriel; Saleh, Narjes A; Haj-Yahya, Rani; Matan, Liat S; Avi, Benshushan

    2018-04-01

    To evaluate β-human chorionic gonadotropin (β-HCG) level and its 24-hour increment as predictors of successful methotrexate treatment for ectopic pregnancy. Data were retrospectively reviewed from women with ectopic pregnancy who were treated by single-dose methotrexate (50 mg/m 2 ) at a university hospital in Jerusalem, Israel, between January 1, 2000, and June 30, 2015. Serum β-HCG before treatment and its percentage increment in the 24 hours before treatment were compared between treatment success and failure groups. Sixty-nine women were included in the study. Single-dose methotrexate treatment was successful for 44 (63.8%) women. Both mean β-HCG level and its 24-hour increment were lower for women with successful treatment than for those with failed treatment (respectively, 1224 IU\\L vs 2362 IU\\L, P=0.018; and 13.5% vs 29.6%, P=0.009). Receiver operator characteristic curve analysis yielded cutoff values of 1600 IU\\L and 14% increment with a positive predictive value of 75% and 82%, respectively, for treatment success. β-HCG level and its 24-hour increment were independent predictors of treatment outcome by logistic regression (both P<0.01). A β-HCG increment of less than 14% in the 24 hours before single-dose methotrexate and serum β-HCG of less than 1600 IU\\L were found to be good predictors of treatment success. © 2017 International Federation of Gynecology and Obstetrics.

  17. Predicting height increment of young-growth red fir in California and southern Oregon

    Treesearch

    K. Leroy Dolph

    1992-01-01

    An equation is given to estimate 10-year height increment for young-growth red fir trees in California and southern Oregon. The independent variables are the individual tree, stand, and site characteristics significantly related to a tree's height growth. Data used to develop the equation came from stem analysis of 492 trees sampled from 56 stands in the study...

  18. Survey of Attitudinal Acceptance of a Children's Incremental Dental Care Program by Parents, Teachers and School Administrators. Final Report.

    ERIC Educational Resources Information Center

    Guess, L. Lynn; And Others

    This report presents an analysis of the attitudes of parents, teachers, and school administrators to the Chattanooga Incremental Dental Care Program. This project provided dental care in the public elementary schools at specific intervals of time to specific age groups in order to establish and maintain a state of oral health. Dental services were…

  19. Investigating Forest Inventory and Analysis-collected tree-ring data from Utah as a proxy for historical climate

    Treesearch

    R. Justin DeRose; W. Shih-Yu (Simon) Wang; John D. Shaw

    2012-01-01

    Increment cores collected as part of the periodic inventory in the Intermountain West were examined for their potential to represent growth and be a proxy for climate (precipitation) over a large region (Utah). Standardized and crossdated time-series created from pinyon pine (n=249) and Douglas-fir (n=274) increment cores displayed spatiotemporal patterns in growth...

  20. Stability analysis of fuzzy parametric uncertain systems.

    PubMed

    Bhiwani, R J; Patre, B M

    2011-10-01

    In this paper, the determination of stability margin, gain and phase margin aspects of fuzzy parametric uncertain systems are dealt. The stability analysis of uncertain linear systems with coefficients described by fuzzy functions is studied. A complexity reduced technique for determining the stability margin for FPUS is proposed. The method suggested is dependent on the order of the characteristic polynomial. In order to find the stability margin of interval polynomials of order less than 5, it is not always necessary to determine and check all four Kharitonov's polynomials. It has been shown that, for determining stability margin of FPUS of order five, four, and three we require only 3, 2, and 1 Kharitonov's polynomials respectively. Only for sixth and higher order polynomials, a complete set of Kharitonov's polynomials are needed to determine the stability margin. Thus for lower order systems, the calculations are reduced to a large extent. This idea has been extended to determine the stability margin of fuzzy interval polynomials. It is also shown that the gain and phase margin of FPUS can be determined analytically without using graphical techniques. Copyright © 2011 ISA. Published by Elsevier Ltd. All rights reserved.

  1. Utilizing Flight Data to Update Aeroelastic Stability Estimates

    NASA Technical Reports Server (NTRS)

    Lind, Rick; Brenner, Marty

    1997-01-01

    Stability analysis of high performance aircraft must account for errors in the system model. A method for computing flutter margins that incorporates flight data has been developed using robust stability theory. This paper considers applying this method to update flutter margins during a post-flight or on-line analysis. Areas of modeling uncertainty that arise when using flight data with this method are investigated. The amount of conservatism in the resulting flutter margins depends on the flight data sets used to update the model. Post-flight updates of flutter margins for an F/A-18 are presented along with a simulation of on-line updates during a flight test.

  2. Engineering analysis division internal note. OFT-1 margin assessment. [results of analysis to determine space shuttle subsystem margins for orbital flight test

    NASA Technical Reports Server (NTRS)

    Austin, L. D., Jr.

    1977-01-01

    The results are documented of an analysis conducted to determine space shuttle vehicle (SSV) subsystem margins for the reference flight profile for the first orbital flight test (OFT-1). In general, the results show increased margins for the OFT-1 indicators when compared to Mission 3A resutls. The inclusion of element and wing aerodynamic variations on OFT-1, in combination with winds and systems dispersions, resulted in the forward Z (FTO1) attach load indicator exceeding specified limits. The inboard and outboard elevon hinge moment margins (9 percent and 3 percent, respectively) on OFT-1 reflect values consistent with the load relief requirements dictated by elevon hinge moment variations. All other structural load indicators for OFT-1 had margins in excess of 10 percent. The SSV first stage stagnation heating indicators for OFT-1 were about 45 percent less than for Mission 3A. The hydraulic systems demands for both missions were essentially the same. The results also show OFT-1 performance requirements from the consideration of winds and dispersions to be approximately 3,300 lbs greater than Mission 3A.

  3. Incremental and comparative health care expenditures for head and neck cancer in the United States.

    PubMed

    Dwojak, Sunshine M; Bhattacharyya, Neil

    2014-10-01

    Determine the incremental costs associated with head and neck cancer (HNCa) and compare the costs with other common cancers. Cross-sectional analysis of a healthcare expenditure database. The Medical Expenditure Panel Survey is a national survey of US households. All cases of HNCa were extracted for 2006, 2008, and 2010. The incremental expenditures associated with HNCa were determined by comparing the healthcare expenditures of individuals with HNCa to the population without cancer, controlling for age, sex, education, insurance status, marital status, geographic region, and comorbidities. Healthcare expenditures for HNCa were then compared to individuals with lung cancer and colon cancer to determine relative healthcare expenditures. An estimated 264,713 patients (annualized) with HNCa were identified. The mean annual healthcare expenditures per individual for HNCa were $23,408 ± $3,397 versus $3,860 ± $52 for those without cancer. The mean adjusted incremental cost associated with HNCa was $15,852 ± $3,297 per individual (P < .001). Within this incremental cost, there was an increased incremental outpatient services cost of $3,495 ± $1,044 (P = .001) and an increased incremental hospital inpatient cost of $6,783 ± $2,894 (P = .020) associated with HNCa. The annual healthcare expenditures per individual fell in between those for lung cancer ($25,267 ± $2,375, P = .607) and colon cancer ($16,975 ± $1,291, P = .055). Despite its lower relative incidence, HNCa is associated with a significant incremental increase in annual healthcare expenditures per individual, which is comparable to or higher than other common cancers. In aggregate, the estimated annual costs associated with HNCa are $4.20 billion. © 2014 The American Laryngological, Rhinological and Otological Society, Inc.

  4. Evaluation of marginal fit of two all-ceramic copings with two finish lines

    PubMed Central

    Subasi, Gulce; Ozturk, Nilgun; Inan, Ozgur; Bozogullari, Nalan

    2012-01-01

    Objectives: This in-vitro study investigated the marginal fit of two all-ceramic copings with 2 finish line designs. Methods: Forty machined stainless steel molar die models with two different margin designs (chamfer and rounded shoulder) were prepared. A total of 40 standardized copings were fabricated and divided into 4 groups (n=10 for each finish line-coping material). Coping materials tested were IPS e.max Press and Zirkonzahn; luting agent was Variolink II. Marginal fit was evaluated after cementation with a stereomicroscope (Leica MZ16). Two-way analysis of variance and Tukey-HSD test were performed to assess the influence of each finish line design and ceramic type on the marginal fit of 2 all-ceramic copings (α =.05). Results: Two-way analysis of variance revealed no statistically significant differences for marginal fit relative to finish lines (P=.362) and ceramic types (P=.065). Conclusion: Within the limitations of this study, both types of all-ceramic copings demonstrated that the mean marginal fit was considered acceptable for clinical application (⩽120 μm). PMID:22509119

  5. Animation and radiobiological analysis of 3D motion in conformal radiotherapy.

    PubMed

    MacKay, R I; Graham, P A; Moore, C J; Logue, J P; Sharrock, P J

    1999-07-01

    To allow treatment plans to be evaluated against the range of expected organ motion and set up error anticipated during treatment. Planning tools have been developed to allow concurrent animation and radiobiological analysis of three dimensional (3D) target and organ motion in conformal radiotherapy. Surfaces fitted to structures outlined on CT studies are projected onto pre-treatment images or onto megavoltage images collected during the patient treatment. Visual simulation of tumour and normal tissue movement is then performed by the application of three dimensional affine transformations, to the selected surface. Concurrent registration of the surface motion with the 3D dose distribution allows calculation of the change in dose to the volume. Realistic patterns of motion can be applied to the structure to simulate inter-fraction motion and set-up error. The biologically effective dose for the structure is calculated for each fraction as the surface moves over the course of the treatment and is used to calculate the normal tissue complication probability (NTCP) or tumour control probability (TCP) for the moving structure. The tool has been used to evaluate conformal therapy plans against set up measurements recorded during patient treatments. NTCP and TCP were calculated for a patient whose set up had been corrected after systematic deviations from plan geometry were measured during treatment, the effect of not making the correction were also assessed. TCP for the moving tumour was reduced if inadequate margins were set for the treatment. Modelling suggests that smaller margins could have been set for the set up corrected during the course of the treatment. The NTCP for the rectum was also higher for the uncorrected set up due to a more rectal tissue falling in the high dose region. This approach provides a simple way for clinical users to utilise information incrementally collected throughout the whole of a patient's treatment. In particular it is possible to test the robustness of a patient plan against a range of possible motion patterns. The methods described represent a move from the inspection of static pre-treatment plans to a review of the dynamic treatment.

  6. The Role of Margin in Link Design and Optimization

    NASA Technical Reports Server (NTRS)

    Cheung, K.

    2015-01-01

    Link analysis is a system engineering process in the design, development, and operation of communication systems and networks. Link models that are mathematical abstractions representing the useful signal power and the undesirable noise and attenuation effects (including weather effects if the signal path transverses through the atmosphere) that are integrated into the link budget calculation that provides the estimates of signal power and noise power at the receiver. Then the link margin is applied which attempts to counteract the fluctuations of the signal and noise power to ensure reliable data delivery from transmitter to receiver. (Link margin is dictated by the link margin policy or requirements.) A simple link budgeting approach assumes link parameters to be deterministic values typically adopted a rule-of-thumb policy of 3 dB link margin. This policy works for most S- and X-band links due to their insensitivity to weather effects. But for higher frequency links like Ka-band, Ku-band, and optical communication links, it is unclear if a 3 dB link margin would guarantee link closure. Statistical link analysis that adopted the 2-sigma or 3-sigma link margin incorporates link uncertainties in the sigma calculation. (The Deep Space Network (DSN) link margin policies are 2-sigma for downlink and 3-sigma for uplink.) The link reliability can therefore be quantified statistically even for higher frequency links. However in the current statistical link analysis approach, link reliability is only expressed as the likelihood of exceeding the signal-to-noise ratio (SNR) threshold that corresponds to a given bit-error-rate (BER) or frame-error-rate (FER) requirement. The method does not provide the true BER or FER estimate of the link with margin, or the required signalto-noise ratio (SNR) that would meet the BER or FER requirement in the statistical sense. In this paper, we perform in-depth analysis on the relationship between BER/FER requirement, operating SNR, and coding performance curve, in the case when the channel coherence time of link fluctuation is comparable or larger than the time duration of a codeword. We compute the "true" SNR design point that would meet the BER/FER requirement by taking into account the fluctuation of signal power and noise power at the receiver, and the shape of the coding performance curve. This analysis yields a number of valuable insights on the design choices of coding scheme and link margin for the reliable data delivery of a communication system - space and ground. We illustrate the aforementioned analysis using a number of standard NASA error-correcting codes.

  7. Abutment design for implant-supported indirect composite molar crowns: reliability and fractography.

    PubMed

    Bonfante, Estevam Augusto; Suzuki, Marcelo; Lubelski, William; Thompson, Van P; de Carvalho, Ricardo Marins; Witek, Lukasz; Coelho, Paulo G

    2012-12-01

    To investigate the reliability of titanium abutments veneered with indirect composites for implant-supported crowns and the possibility to trace back the fracture origin by qualitative fractographic analysis. Large base (LB) (6.4-mm diameter base, with a 4-mm high cone in the center for composite retention), small base (SB-4) (5.2-mm base, 4-mm high cone), and small base with cone shortened to 2 mm (SB-2) Ti abutments were used. Each abutment received incremental layers of indirect resin composite until completing the anatomy of a maxillary molar crown. Step-stress accelerated-life fatigue testing (n = 18 each) was performed in water. Weibull curves with use stress of 200 N for 50,000 and 100,000 cycles were calculated. Probability Weibull plots examined the differences between groups. Specimens were inspected in light-polarized and scanning electron microscopes for fractographic analysis. Use level probability Weibull plots showed Beta values of 0.27 for LB, 0.32 for SB-4, and 0.26 for SB-2, indicating that failures were not influenced by fatigue and damage accumulation. The data replotted as Weibull distribution showed no significant difference in the characteristic strengths between LB (794 N) and SB-4 abutments (836 N), which were both significantly higher than SB-2 (601 N). Failure mode was cohesive within the composite for all groups. Fractographic markings showed that failures initiated at the indentation area and propagated toward the margins of cohesively failed composite. Reliability was not influenced by abutment design. Qualitative fractographic analysis of the failed indirect composite was feasible. © 2012 by the American College of Prosthodontists.

  8. Cost-effectiveness of WHO-Recommended Algorithms for TB Case Finding at Ethiopian HIV Clinics.

    PubMed

    Adelman, Max W; McFarland, Deborah A; Tsegaye, Mulugeta; Aseffa, Abraham; Kempker, Russell R; Blumberg, Henry M

    2018-01-01

    The World Health Organization (WHO) recommends active tuberculosis (TB) case finding and a rapid molecular diagnostic test (Xpert MTB/RIF) to detect TB among people living with HIV (PLHIV) in high-burden settings. Information on the cost-effectiveness of these recommended strategies is crucial for their implementation. We conducted a model-based cost-effectiveness analysis comparing 2 algorithms for TB screening and diagnosis at Ethiopian HIV clinics: (1) WHO-recommended symptom screen combined with Xpert for PLHIV with a positive symptom screen and (2) current recommended practice algorithm (CRPA; based on symptom screening, smear microscopy, and clinical TB diagnosis). Our primary outcome was US$ per disability-adjusted life-year (DALY) averted. Secondary outcomes were additional true-positive diagnoses, and false-negative and false-positive diagnoses averted. Compared with CRPA, combining a WHO-recommended symptom screen with Xpert was highly cost-effective (incremental cost of $5 per DALY averted). Among a cohort of 15 000 PLHIV with a TB prevalence of 6% (900 TB cases), this algorithm detected 8 more true-positive cases than CRPA, and averted 2045 false-positive and 8 false-negative diagnoses compared with CRPA. The WHO-recommended algorithm was marginally costlier ($240 000) than CRPA ($239 000). In sensitivity analysis, the symptom screen/Xpert algorithm was dominated at low Xpert sensitivity (66%). In this model-based analysis, combining a WHO-recommended symptom screen with Xpert for TB diagnosis among PLHIV was highly cost-effective ($5 per DALY averted) and more sensitive than CRPA in a high-burden, resource-limited setting.

  9. Magma interaction in the root of an arc batholith

    NASA Astrophysics Data System (ADS)

    Chapman, T.; Robbins, V.; Clarke, G. L.; Daczko, N. R.; Piazolo, S.

    2016-12-01

    Fiordland, New Zealand, preserves extensive Cretaceous arc plutons, emplaced into parts of the Delamerian/Ross Orogen. Dioritic to gabbroic material emplaced at mid to lower crustal levels are exposed in the Malaspina Pluton (c. 1.2 GPa) and the Breaksea Orthogneiss (c. 1.8 GPa). Distinct magmatic pulses can be mapped in both of these plutons consistent with cycles of melt advection. Relationships are consistent with predictions from lower crustal processing zones (MASH and hot zones) considered important in the formation of Cordilleran margins. Metamorphic garnet growth is enhanced along magmatic contacts, such as where hornblende gabbronorite is cut by garnet-clinopyroxene-bearing diorite. Such features are consistent with cycles of incremental emplacement, younger magma having induced localised garnet granulite metamorphism in wall rock of older material. Temperature estimates and microstructures preserved in garnet granulite are consistent with sub-solidus, water-poor conditions in both the Malaspina and Breaksea Orthogneiss. The extent and conditions of the metamorphism implies conditions and duration was incapable of partially melting older wall rock material. The nature of interactions in intermediate to basic compositions are assessed in terms of magma genesis in the Cretaceous batholith. Most of the upper crustal felsic I-type magmatism along the margin being controlled by high-pressure garnet-clinopyroxene fractionation.

  10. Bayesian inference based on stationary Fokker-Planck sampling.

    PubMed

    Berrones, Arturo

    2010-06-01

    A novel formalism for bayesian learning in the context of complex inference models is proposed. The method is based on the use of the stationary Fokker-Planck (SFP) approach to sample from the posterior density. Stationary Fokker-Planck sampling generalizes the Gibbs sampler algorithm for arbitrary and unknown conditional densities. By the SFP procedure, approximate analytical expressions for the conditionals and marginals of the posterior can be constructed. At each stage of SFP, the approximate conditionals are used to define a Gibbs sampling process, which is convergent to the full joint posterior. By the analytical marginals efficient learning methods in the context of artificial neural networks are outlined. Offline and incremental bayesian inference and maximum likelihood estimation from the posterior are performed in classification and regression examples. A comparison of SFP with other Monte Carlo strategies in the general problem of sampling from arbitrary densities is also presented. It is shown that SFP is able to jump large low-probability regions without the need of a careful tuning of any step-size parameter. In fact, the SFP method requires only a small set of meaningful parameters that can be selected following clear, problem-independent guidelines. The computation cost of SFP, measured in terms of loss function evaluations, grows linearly with the given model's dimension.

  11. Professionalism in global, personalized cancer care: restoring authenticity and integrity.

    PubMed

    Surbone, Antonella

    2013-01-01

    Personalized medicine is revolutionizing cancer care and creating new expectations among oncologists and patients. At present the benefit is still marginal, however, and must be understood as incremental. In addition, cultural and resource disparities limit the sustainability of new cancer therapies on a global scale. Adequate instruments are needed to enable our exercise of sound and honest judgment in distinguishing breakthrough treatments from those that yield only marginal or doubtful improvements, and to develop strategies for formulation and correct application of balanced guidelines for sustainable cancer care. Professionalism requires that the acquisition of knowledge and skills go hand in hand with moral education in the intellectual virtues of humility, perseverance, adaptability, communicativeness, and commitment to resist self-deception or conflicts of interest. Hidden curricula undermine the moral values of medicine: these must be understood and uncovered. We should possess a special body of knowledge, skills, and values that allow us to change our practices when appropriate and to be stewards of society's limited resources through proper communication with our patients and families. In the era of personalized oncology and global issues of sustainability, professional authenticity and integrity in cancer clinical practice are key to bridging the gaps between true and false expectations of patients and the public.

  12. Cost-effectiveness analysis of entecavir versus lamivudine in the first-line treatment of Australian patients with chronic hepatitis B.

    PubMed

    Arnold, Elizabeth; Yuan, Yong; Iloeje, Uchenna; Cook, Greg

    2008-01-01

    Chronic hepatitis B (CHB) virus infection is a major global healthcare problem. The recent introduction of entecavir in Australia for the treatment of CHB patients in the naive treatment setting has triggered significant optimism with regards to improved clinical outcomes for CHB patients. To estimate, from an Australian healthcare perspective, the cost effectiveness of entecavir 0.5 mg/day versus lamivudine 100 mg/day in the treatment of CHB patients naive to nucleos(t)ide therapy. A cost-utility analysis to project the clinical and economic outcomes associated with CHB disease and treatment was conducted by developing two decision-tree models specific to hepatitis B e antigen-positive (HBeAg+ve) and HBeAg-ve CHB patient subsets. This analysis was constructed using the Australian payer perspective of direct costs and outcomes, with indirect medical costs and lost productivity not being included. The study population comprised a hypothetical cohort of 1000 antiviral treatment-naive CHB patients who received either entecavir 0.5 mg/day or lamivudine 100 mg/day at model entry. The population of patients used in this analysis was representative of those patients likely to receive initial antiviral therapy in clinical practice in Australia. The long-term cost effectiveness of entecavir compared with lamivudine in the first-line treatment of CHB patients was expressed as an incremental cost per life-year gained (LYG) or QALY gained. Results revealed that the availability of entecavir 0.5 mg/day as part of the Australian hepatologist's treatment armamentarium should result in significantly lower future rates of compensated cirrhosis (CC), decompensated cirrhosis (DC), and hepatocellular carcinoma (HCC) events (i.e. 54 fewer cases of CC, seven fewer cases of DC, and 20 fewer cases of HCC over the model's timeframe for HBeAg+ve CHB patients, and 69 fewer cases of CC, eight fewer cases of DC and 25 fewer cases of HCC over the model's timeframe for HBeAg-ve CHB patients). Compared with lamivudine 100 mg/day, entecavir 0.5 mg/day generated an estimated incremental cost per LYG of Australian dollars ($A, year 2006 values) 5046 and an estimated incremental cost per QALY of $A5952 in the HBeAg+ve CHB patient population, an estimated incremental cost per LYG of $A7063 and an estimated incremental cost per QALY of $A8003 in the HBeAg-ve CHB patient population, and an overall estimated incremental cost per LYG of $A5853 and an estimated incremental cost per QALY of $A6772 in the general CHB population. The availability of entecavir in Australian clinical practice should make long-term suppression of hepatitis B virus replication increasingly attainable, resulting in fewer CHB sequelae, at an acceptable financial cost.

  13. Impact of Resection Margin Distance on Survival of Pancreatic Cancer: A Systematic Review and Meta-Analysis

    PubMed Central

    Kim, Kyung Su; Kwon, Jeanny; Kim, Kyubo; Chie, Eui Kyu

    2017-01-01

    Purpose While curative resection is the only chance of cure in pancreatic cancer, controversies exist about the impact of surgical margin status on survival. Non-standardized pathologic report and different criteria on the R1 status made it difficult to implicate adjuvant therapy after resection based on the margin status. We evaluated the influence of resection margins on survival by meta-analysis. Materials and Methods We thoroughly searched electronic databases of PubMed, EMBASE, and Cochrane Library. We included studies reporting survival outcomes with different margin status: involved margin (R0 mm), margin clearance with ≤ 1 mm (R0-1 mm), and margin with > 1 mm (R>1 mm). Hazard ratio (HR) for overall survival was extracted, and a random-effects model was used for pooled analysis. Results A total of eight retrospective studies involving 1,932 patients were included. Pooled HR for overall survival showed that patients with R>1 mm had reduced risk of death than those with R0-1 mm (HR, 0.74; 95% confidence interval [CI], 0.61 to 0.88; p=0.001). In addition, patients with R0-1 mm had reduced risk of death than those with R0 mm (HR, 0.81; 95% CI, 0.72 to 0.91; p < 0.001). There was no heterogeneity between the included studies (I2 index, 42% and 0%; p=0.10 and p=0.82, respectively). Conclusion Our results suggest that stratification of the patients based on margin status is warranted in the clinical trials assessing the role of adjuvant treatment for pancreatic cancer. PMID:27561314

  14. Validity of the alcohol purchase task: a meta-analysis.

    PubMed

    Kiselica, Andrew M; Webber, Troy A; Bornovalova, Marina A

    2016-05-01

    Behavioral economists assess alcohol consumption as a function of unit price. This method allows construction of demand curves and demand indices, which are thought to provide precise numerical estimates of risk for alcohol problems. One of the more commonly used behavioral economic measures is the Alcohol Purchase Task (APT). Although the APT has shown promise as a measure of risk for alcohol problems, the construct validity and incremental utility of the APT remain unclear. This paper presents a meta-analysis of the APT literature. Sixteen studies were included in the meta-analysis. Studies were gathered via searches of the PsycInfo, PubMed, Web of Science and EconLit research databases. Random-effects meta-analyses with inverse variance weighting were used to calculate summary effect sizes for each demand index-drinking outcome relationship. Moderation of these effects by drinking status (regular versus heavy drinkers) was examined. Additionally, tests of the incremental utility of the APT indices in predicting drinking problems above and beyond measuring alcohol consumption were performed. The APT indices were correlated in the expected directions with drinking outcomes, although many effects were small in size. These effects were typically not moderated by the drinking status of the samples. Additionally, the intensity metric demonstrated incremental utility in predicting alcohol use disorder symptoms beyond measuring drinking. The Alcohol Purchase Task appears to have good construct validity, but limited incremental utility in estimating risk for alcohol problems. © 2015 Society for the Study of Addiction.

  15. Analysis of vertical marginal discrepancy in feldspathic porcelain crowns manufactured with different CAD/CAM systems: Closed and open.

    PubMed

    Kricheldorf, Fabio; Bueno, Cleuber Rodrigo de Souza; Amaral, Wilson da Silva; Junior, Joel Ferreira Santiago; Filho, Hugo Nary

    2018-01-01

    The objective of this study is to compare the marginal adaptation of feldspathic porcelain crowns using two computer-aided design/computer-aided manufacturing systems, one of them is open and the other is closed. Twenty identical titanium abutments were divided into two groups: open system (OS), where ceramic crowns were created using varied equipment and software, and closed system (CS), where ceramic crowns were created using the CEREC system. Through optical microscopy analysis, we assess the marginal adaptation of the prosthetic interfaces. The data were subjected to the distribution of normality and variance. The t -test was used for the analysis of the comparison factor between the groups, and the one-way ANOVA was used to compare the variance of crown analysis regions within the group. A significance level of 5% was considered for the analyses. There was a significant difference between the systems ( P = 0.007), with the CS group having the higher mean (23.75 μm ± 3.05) of marginal discrepancy when compared to the open group (17.94 μm ± 4.77). Furthermore, there were no differences in marginal discrepancy between the different points between the groups ( P ≥ 0.05). The studied groups presented results within the requirements set out in the literature. However, the OS used presented better results in marginal adaptation.

  16. 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

  17. Multiscale Characterization of the Probability Density Functions of Velocity and Temperature Increment Fields

    NASA Astrophysics Data System (ADS)

    DeMarco, Adam Ward

    The turbulent motions with the atmospheric boundary layer exist over a wide range of spatial and temporal scales and are very difficult to characterize. Thus, to explore the behavior of such complex flow enviroments, it is customary to examine their properties from a statistical perspective. Utilizing the probability density functions of velocity and temperature increments, deltau and deltaT, respectively, this work investigates their multiscale behavior to uncover the unique traits that have yet to be thoroughly studied. Utilizing diverse datasets, including idealized, wind tunnel experiments, atmospheric turbulence field measurements, multi-year ABL tower observations, and mesoscale models simulations, this study reveals remarkable similiarities (and some differences) between the small and larger scale components of the probability density functions increments fields. This comprehensive analysis also utilizes a set of statistical distributions to showcase their ability to capture features of the velocity and temperature increments' probability density functions (pdfs) across multiscale atmospheric motions. An approach is proposed for estimating their pdfs utilizing the maximum likelihood estimation (MLE) technique, which has never been conducted utilizing atmospheric data. Using this technique, we reveal the ability to estimate higher-order moments accurately with a limited sample size, which has been a persistent concern for atmospheric turbulence research. With the use robust Goodness of Fit (GoF) metrics, we quantitatively reveal the accuracy of the distributions to the diverse dataset. Through this analysis, it is shown that the normal inverse Gaussian (NIG) distribution is a prime candidate to be used as an estimate of the increment pdfs fields. Therefore, using the NIG model and its parameters, we display the variations in the increments over a range of scales revealing some unique scale-dependent qualities under various stability and ow conditions. This novel approach can provide a method of characterizing increment fields with the sole use of only four pdf parameters. Also, we investigate the capability of the current state-of-the-art mesoscale atmospheric models to predict the features and highlight the potential for use for future model development. With the knowledge gained in this study, a number of applications can benefit by using our methodology, including the wind energy and optical wave propagation fields.

  18. The Space Station decision - Incremental politics and technological choice

    NASA Technical Reports Server (NTRS)

    Mccurdy, Howard E.

    1990-01-01

    Using primary documents and interviews with participants, this book describes the events that led up to the 1984 decision that NASA should build a permanently occupied, international space station in low earth orbit. The role that civil servants in NASA played in initiating the program is highlighted. The trail of the Space Station proposal as its advocates devised strategies to push it through the White House policy review process is followed. The critical analysis focuses on the way in which 'incrementalism' (the tendency of policy makers to introduce incremental changes once projects are under way) operated in connection with the Space Station program. The book calls for a commitment to a long-range space policy.

  19. Effects of health empowerment intervention on resilience of adolescents in a tribal area: A study using the Solomon four-groups design.

    PubMed

    Sarkar, Kaushik; Dasgupta, Aparajita; Sinha, Multipada; Shahbabu, Bhaskar

    2017-10-01

    Resilience prevents the emergence of stress-related mental health problems among adolescents. Adolescents in tribal areas of India are more prone to develop such problems. The primary objective was to determine the effect of combined life skills-based health empowerment intervention on the resilience of school-going adolescents in a tribal area. The secondary objectives were to determine the effect of the intervention on internal health locus of control and self-determination and to compare the effect of intervention on resilience between non-tribal and tribal adolescents. We conducted this quasi-experimental study using a Solomon four-group design among 742 adolescents in two schools of Purulia, West Bengal, India. Students of the pretested group were examined for resilience using the Child Youth Resilience Measurement scale. A life skills education-based health empowerment intervention was administered among students of the experimental group. Post-test data on resilience, self-determination, internal health locus of control and pathological behaviour was obtained 3 months after the completion of intervention. A multi-level general linear mixed model was constructed to determine the effect of intervention on resilience. Resilience was less among tribal adolescents at baseline. The intervention significantly improved resilience [β Adjusted  = 11.19 (95% CI = 10.55, 11.83], with a greater increase for tribal adolescents [β tribal-nontribal  = 1.53 (95% CI = 0.03, 3.03)]. The intervention also significantly improved internal health locus of control (marginal mean increment 1.38 ± 0.05), self-determination (marginal mean increment 3.71 ± 0.09) and reduced pathological behaviour of the adolescents. Our study informed the current health policy that the existing life skills education-based programme should be reviewed and modified to include generic life skills, and the life skills education-based programme should be coupled with developmental interventions aimed at improving adult education and family climate for optimum effect on mental health and health behaviour of adolescents. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Independent Component Analysis of Textures

    NASA Technical Reports Server (NTRS)

    Manduchi, Roberto; Portilla, Javier

    2000-01-01

    A common method for texture representation is to use the marginal probability densities over the outputs of a set of multi-orientation, multi-scale filters as a description of the texture. We propose a technique, based on Independent Components Analysis, for choosing the set of filters that yield the most informative marginals, meaning that the product over the marginals most closely approximates the joint probability density function of the filter outputs. The algorithm is implemented using a steerable filter space. Experiments involving both texture classification and synthesis show that compared to Principal Components Analysis, ICA provides superior performance for modeling of natural and synthetic textures.

  1. 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)

  2. Effects of general fatigue induced by incremental maximal exercise test on gait stability and variability of healthy young subjects.

    PubMed

    Vieira, Marcus Fraga; de Sá E Souza, Gustavo Souto; Lehnen, Georgia Cristina; Rodrigues, Fábio Barbosa; Andrade, Adriano O

    2016-10-01

    The purpose of this study was to determine whether general fatigue induced by incremental maximal exercise test (IMET) affects gait stability and variability in healthy subjects. Twenty-two young healthy male subjects walked in a treadmill at preferred walking speed for 4min prior (PreT) the test, which was followed by three series of 4min of walking with 4min of rest among them. Gait variability was assessed using walk ratio (WR), calculated as step length normalized by step frequency, root mean square (RMSratio) of trunk acceleration, standard deviation of medial-lateral trunk acceleration between strides (VARML), coefficient of variation of step frequency (SFCV), length (SLCV) and width (SWCV). Gait stability was assessed using margin of stability (MoS) and local dynamic stability (λs). VARML, SFCV, SLCV and SWCV increased after the test indicating an increase in gait variability. MoS decreased and λs increased after the test, indicating a decrease in gait stability. All variables showed a trend to return to PreT values, but the 20-min post-test interval appears not to be enough for a complete recovery. The results showed that general fatigue induced by IMET alters negatively the gait, and an interval of at least 20min should be considered for injury prevention in tasks with similar demands. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Addiction, agency, and the politics of self-control: doing harm reduction in a heroin users' group.

    PubMed

    Gowan, Teresa; Whetstone, Sarah; Andic, Tanja

    2012-04-01

    Our 2007-2009 ethnography describes and analyses the practice of harm reduction in a heroin users' group in the midwestern United States. While dominant addiction interventions conceptualize the addict as powerless - either through moral or physical weakness - this group contested such "commonsense," treating illicit drug use as one of many ways that modern individuals attempt to "fill the void." Insisting on the destigmatization of addiction and the normalization of illicit drug use, the group helped its members work on incremental steps toward self-management. Although "Connection Points" had very limited resources to improve the lives of its members, our work suggests that the users' group did much to restore self-respect, rational subjectivity, and autonomy to a group historically represented as incapable of reason and self-control. As the users cohered as a community, they developed a critique of the oppressions suffered by "junkies," discussed their rights and entitlements, and even planned the occasional political action. Engaging with literature on the cultural construction of agency and responsibility, we consider, but ultimately complicate, the conceptualization of needle exchange as a "neoliberal" form of population management. Within the context of the United States' War on Drugs, the group's work on destigmatization, health education, and the practice of incremental control showed the potential for reassertions of social citizenship within highly marginal spaces. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Projecting the impact of a nationwide school plain water access intervention on childhood obesity: a cost-benefit analysis.

    PubMed

    An, R; Xue, H; Wang, L; Wang, Y

    2017-09-22

    This study aimed to project the societal cost and benefit of an expansion of a water access intervention that promotes lunchtime plain water consumption by placing water dispensers in New York school cafeterias to all schools nationwide. A decision model was constructed to simulate two events under Markov chain processes - placing water dispensers at lunchtimes in school cafeterias nationwide vs. no action. The incremental cost pertained to water dispenser purchase and maintenance, whereas the incremental benefit was resulted from cases of childhood overweight/obesity prevented and corresponding lifetime direct (medical) and indirect costs saved. Based on the decision model, the estimated incremental cost of the school-based water access intervention is $18 per student, and the corresponding incremental benefit is $192, resulting in a net benefit of $174 per student. Subgroup analysis estimates the net benefit per student to be $199 and $149 among boys and girls, respectively. Nationwide adoption of the intervention would prevent 0.57 million cases of childhood overweight, resulting in a lifetime cost saving totalling $13.1 billion. The estimated total cost saved per dollar spent was $14.5. The New York school-based water access intervention, if adopted nationwide, may have a considerably favourable benefit-cost portfolio. © 2017 World Obesity Federation.

  5. Stable Isotope Analysis of Extant Lamnoid Shark Centra: A New Tool in Age Determination?

    NASA Astrophysics Data System (ADS)

    Labs, J.

    2003-12-01

    The oxygen isotopes of fourteen vertebral centra from ten extant lamnoid sharks (including Carcharodon carcharias [great white], Isurus paucus [longfin mako], and Isurus oxyrinchus [shortfin mako]) were sampled and measured along the growth axis to determine the periodicity of incremental growth represented in the centra. As part of the internal (endochondral) skeleton, shark centra are composed initially of hyaline cartilage, which then secondarily ossifies during ontogeny forming calcified hydroxyapatite bone. The incremental growth of shark centra forms definite growth rings, with darker denser portions being deposited during slower growth times (i.e., winter) and lighter portions being deposited during more rapid growth (i.e., summer). Thus, shark centra, whether they are extant or extinct, are characterized by clearly delineated incremental growth couplets. The problem with this general rule is that there are several factors in which the growth of these couplets can vary depending upon physical environment (including temperature and water depth), food availability, and stress. The challenge for paleobiological interpretations is how to interpret the periodicity of this growth. It can generally be assumed that these bands are annual, but it is uncertain the extent to which exceptions to the rule occur. Stable isotopic analysis provides the potential to independently determine the periodicity of the growth increments and ultimately the ontogenetic age of an individual.

  6. Using Hand Grip Force as a Correlate of Longitudinal Acceleration Comfort for Rapid Transit Trains

    PubMed Central

    Guo, Beiyuan; Gan, Weide; Fang, Weining

    2015-01-01

    Longitudinal acceleration comfort is one of the essential metrics used to evaluate the ride comfort of train. The aim of this study was to investigate the effectiveness of using hand grip force as a correlate of longitudinal acceleration comfort of rapid transit trains. In the paper, a motion simulation system was set up and a two-stage experiment was designed to investigate the role of the grip force on the longitudinal comfort of rapid transit trains. The results of the experiment show that the incremental grip force was linearly correlated with the longitudinal acceleration value, while the incremental grip force had no correlation with the direction of the longitudinal acceleration vector. The results also show that the effects of incremental grip force and acceleration duration on the longitudinal comfort of rapid transit trains were significant. Based on multiple regression analysis, a step function model was established to predict the longitudinal comfort of rapid transit trains using the incremental grip force and the acceleration duration. The feasibility and practicably of the model was verified by a field test. Furthermore, a comparative analysis shows that the motion simulation system and the grip force based model were valid to support the laboratory studies on the longitudinal comfort of rapid transit trains. PMID:26147730

  7. An incremental strategy for calculating consistent discrete CFD sensitivity derivatives

    NASA Technical Reports Server (NTRS)

    Korivi, Vamshi Mohan; Taylor, Arthur C., III; Newman, Perry A.; Hou, Gene W.; Jones, Henry E.

    1992-01-01

    In this preliminary study involving advanced computational fluid dynamic (CFD) codes, an incremental formulation, also known as the 'delta' or 'correction' form, is presented for solving the very large sparse systems of linear equations which are associated with aerodynamic sensitivity analysis. For typical problems in 2D, a direct solution method can be applied to these linear equations which are associated with aerodynamic sensitivity analysis. For typical problems in 2D, a direct solution method can be applied to these linear equations in either the standard or the incremental form, in which case the two are equivalent. Iterative methods appear to be needed for future 3D applications; however, because direct solver methods require much more computer memory than is currently available. Iterative methods for solving these equations in the standard form result in certain difficulties, such as ill-conditioning of the coefficient matrix, which can be overcome when these equations are cast in the incremental form; these and other benefits are discussed. The methodology is successfully implemented and tested in 2D using an upwind, cell-centered, finite volume formulation applied to the thin-layer Navier-Stokes equations. Results are presented for two laminar sample problems: (1) transonic flow through a double-throat nozzle; and (2) flow over an isolated airfoil.

  8. 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.

  9. Effect of respiratory muscle training on exercise performance in healthy individuals: a systematic review and meta-analysis.

    PubMed

    Illi, Sabine K; Held, Ulrike; Frank, Irène; Spengler, Christina M

    2012-08-01

    Two distinct types of specific respiratory muscle training (RMT), i.e. respiratory muscle strength (resistive/threshold) and endurance (hyperpnoea) training, have been established to improve the endurance performance of healthy individuals. We performed a systematic review and meta-analysis in order to determine the factors that affect the change in endurance performance after RMT in healthy subjects. A computerized search was performed without language restriction in MEDLINE, EMBASE and CINAHL and references of original studies and reviews were searched for further relevant studies. RMT studies with healthy individuals assessing changes in endurance exercise performance by maximal tests (constant load, time trial, intermittent incremental, conventional [non-intermittent] incremental) were screened and abstracted by two independent investigators. A multiple linear regression model was used to identify effects of subjects' fitness, type of RMT (inspiratory or combined inspiratory/expiratory muscle strength training, respiratory muscle endurance training), type of exercise test, test duration and type of sport (rowing, running, swimming, cycling) on changes in performance after RMT. In addition, a meta-analysis was performed to determine the effect of RMT on endurance performance in those studies providing the necessary data. The multiple linear regression analysis including 46 original studies revealed that less fit subjects benefit more from RMT than highly trained athletes (6.0% per 10 mL · kg⁻¹ · min⁻¹ decrease in maximal oxygen uptake, 95% confidence interval [CI] 1.8, 10.2%; p = 0.005) and that improvements do not differ significantly between inspiratory muscle strength and respiratory muscle endurance training (p = 0.208), while combined inspiratory and expiratory muscle strength training seems to be superior in improving performance, although based on only 6 studies (+12.8% compared with inspiratory muscle strength training, 95% CI 3.6, 22.0%; p = 0.006). Furthermore, constant load tests (+16%, 95% CI 10.2, 22.9%) and intermittent incremental tests (+18.5%, 95% CI 10.8, 26.3%) detect changes in endurance performance better than conventional incremental tests (both p < 0.001) with no difference between time trials and conventional incremental tests (p = 0.286). With increasing test duration, improvements in performance are greater (+0.4% per minute test duration, 95% CI 0.1, 0.6%; p = 0.011) and the type of sport does not influence the magnitude of improvements (all p > 0.05). The meta-analysis, performed on eight controlled trials revealed a significant improvement in performance after RMT, which was detected by constant load tests, time trials and intermittent incremental tests, but not by conventional incremental tests. RMT improves endurance exercise performance in healthy individuals with greater improvements in less fit individuals and in sports of longer durations. The two most common types of RMT (inspiratory muscle strength and respiratory muscle endurance training) do not differ significantly in their effect, while combined inspiratory/expiratory strength training might be superior. Improvements are similar between different types of sports. Changes in performance can be detected by constant load tests, time trials and intermittent incremental tests only. Thus, all types of RMT can be used to improve exercise performance in healthy subjects but care must be taken regarding the test used to investigate the improvements.

  10. Sociobehavioral Factors Associated with Caries Increment: A Longitudinal Study from 24 to 36 Months Old Children in Thailand

    PubMed Central

    Peltzer, Karl; Mongkolchati, Aroonsri; Satchaiyan, Gamon; Rajchagool, Sunsanee; Pimpak, Taksin

    2014-01-01

    The aim of this study is to investigate sociobehavioral risk factors from the prenatal period until 36 months of age, and the caries increment from 24 to 36 months of the child in Thailand. The data utilized in this study come from the prospective cohort study of Thai children (PCTC) from prenatal to 36 months of the child in Mueang Nan district, Northern Thailand. The total sample size recruited was 783 infants. The sample size with dental caries data was 603 and 597, at 24 months and at 36 months, respectively. The sample size of having two assessment points with a dental examination (at 24 months and at 36 months) was 597. Results indicate that the caries increment was 52.9%, meaning from 365 caries free children at 24 months 193 had developed dental caries at 36 months. The prevalence of dental caries was 34.2% at 24 months (n = 206) and 68.5% at 36 months of age (n = 409). In bivariate analysis, higher education of the mother, lower household income, bottle feeding of the infant, frequent sweet candy consumptions, and using rain or well water as drinking water were associated with dental caries increment, while in multivariate conditional logistic regression analysis lower household income, higher education of the mother, and using rain or well water as drinking water remained associated with dental caries increment. In conclusion, a very significant increase in caries development was observed, and oral health may be influenced by sociobehavioural risk factors. PMID:25329535

  11. Incremental cost of postacute care in nursing homes.

    PubMed

    Spector, William D; Limcangco, Maria Rhona; Ladd, Heather; Mukamel, Dana

    2011-02-01

    To determine whether the case mix index (CMI) based on the 53-Resource Utilization Groups (RUGs) captures all the cross-sectional variation in nursing home (NH) costs or whether NHs that have a higher percent of Medicare skilled care days (%SKILLED) have additional costs. DATA AND SAMPLE: Nine hundred and eighty-eight NHs in California in 2005. Data are from Medicaid cost reports, the Minimum Data Set, and the Economic Census. We estimate hybrid cost functions, which include in addition to outputs, case mix, ownership, wages, and %SKILLED. Two-stage least-square (2SLS) analysis was used to deal with the potential endogeneity of %SKILLED and CMI. On average 11 percent of NHs days were due to skilled care. Based on the 2SLS model, %SKILLED is associated with costs even when controlling for CMI. The marginal cost of a one percentage point increase in %SKILLED is estimated at U.S.$70,474 or about 1.2 percent of annual costs for the average cost facility. Subanalyses show that the increase in costs is mainly due to additional expenses for nontherapy ancillaries and rehabilitation. The 53-RUGs case mix does not account completely for all the variation in actual costs of care for postacute patients in NHs. © Health Research and Educational Trust.

  12. Incremental Cost of Postacute Care in Nursing Homes

    PubMed Central

    Spector, William D; Limcangco, Maria Rhona; Ladd, Heather; Mukamel, Dana A

    2011-01-01

    Objectives To determine whether the case mix index (CMI) based on the 53-Resource Utilization Groups (RUGs) captures all the cross-sectional variation in nursing home (NH) costs or whether NHs that have a higher percent of Medicare skilled care days (%SKILLED) have additional costs. Data and Sample Nine hundred and eighty-eight NHs in California in 2005. Data are from Medicaid cost reports, the Minimum Data Set, and the Economic Census. Research Design We estimate hybrid cost functions, which include in addition to outputs, case mix, ownership, wages, and %SKILLED. Two-stage least-square (2SLS) analysis was used to deal with the potential endogeneity of %SKILLED and CMI. Results On average 11 percent of NHs days were due to skilled care. Based on the 2SLS model, %SKILLED is associated with costs even when controlling for CMI. The marginal cost of a one percentage point increase in %SKILLED is estimated at U.S.$70,474 or about 1.2 percent of annual costs for the average cost facility. Subanalyses show that the increase in costs is mainly due to additional expenses for nontherapy ancillaries and rehabilitation. Conclusion The 53-RUGs case mix does not account completely for all the variation in actual costs of care for postacute patients in NHs. PMID:21029085

  13. Nutritional Risk is Associated with Chronic Musculoskeletal Pain in Community-dwelling Older Persons: The PAINEL Study.

    PubMed

    Bárbara Pereira Costa, Aline; Andrade Carneiro Machado, Luciana; Marcos Domingues Dias, João; Keller Coelho de Oliveira, Adriana; Ude Viana, Joana; da Silva, Sílvia Lanziotti Azevedo; Gonçalves Pereira Couto, Flávia; Lustosa Torres, Juliana; Mendes, Liliane P; Correa Dias, Rosangela

    2016-01-01

    Malnutrition is a risk factor for noncommunicable diseases related to ageing, and it can also contribute to musculoskeletal health. This study investigated whether nutritional risk is associated with chronic musculoskeletal pain in community-dwelling older persons. Nutritional risk was assessed by the DETERMINE Checklist. Chronic musculoskeletal pain was defined as the presence of pain in the past six months that did not disappear for at least 30 consecutive days. Multivariate logistic regression including confounding variables was used for the analysis. The sample was comprised of 383 participants (age 75.6 ± SD 6.1); the majority were at moderate-to-high nutritional risk (69%) and approximately one third presented chronic musculoskeletal pain (30%). The nutritional risk score was independently associated with chronic musculoskeletal pain: adding one unit in the risk score produces an 11% increment in the odds of presenting pain (OR 1.109, 95% CI 1.022-1.204). Individuals classified into moderate- or high-risk categories also had substantially higher odds (∼90%) of presenting chronic musculoskeletal pain when compared to those in the low-risk category, although our findings were only marginally significant. This is the first study to demonstrate the association between nutritional risk and chronic musculoskeletal pain above and beyond the contributed effects from relevant confounders.

  14. A novel method to quantify and compare anatomical shape: application in cervix cancer radiotherapy

    NASA Astrophysics Data System (ADS)

    Oh, Seungjong; Jaffray, David; Cho, Young-Bin

    2014-06-01

    Adaptive radiation therapy (ART) had been proposed to restore dosimetric deficiencies during treatment delivery. In this paper, we developed a technique of Geometric reLocation for analyzing anatomical OBjects' Evolution (GLOBE) for a numerical model of tumor evolution under radiation therapy and characterized geometric changes of the target using GLOBE. A total of 174 clinical target volumes (CTVs) obtained from 32 cervical cancer patients were analyzed. GLOBE consists of three main steps; step (1) deforming a 3D surface object to a sphere by parametric active contour (PAC), step (2) sampling a deformed PAC on 642 nodes of icosahedron geodesic dome for reference frame, and step (3) unfolding 3D data to 2D plane for convenient visualization and analysis. The performance was evaluated with respect to (1) convergence of deformation (iteration number and computation time) and (2) accuracy of deformation (residual deformation). Based on deformation vectors from planning CTV to weekly CTVs, target specific (TS) margins were calculated on each sampled node of GLOBE and the systematic (Σ) and random (σ) variations of the vectors were calculated. Population based anisotropic (PBA) margins were generated using van Herk's margin recipe. GLOBE successfully modeled 152 CTVs from 28 patients. Fast convergence was observed for most cases (137/152) with the iteration number of 65 ± 74 (average ± STD) and the computation time of 13.7 ± 18.6 min. Residual deformation of PAC was 0.9 ± 0.7 mm and more than 97% was less than 3 mm. Margin analysis showed random nature of TS-margin. As a consequence, PBA-margins perform similarly to ISO-margins. For example, PBA-margins for 90% patients' coverage with 95% dose level is close to 13 mm ISO-margins in the aspect of target coverage and OAR sparing. GLOBE demonstrates a systematic analysis of tumor motion and deformation of patients with cervix cancer during radiation therapy and numerical modeling of PBA-margin on 642 locations of CTV surface.

  15. A Numerical Process Control Method for Circular-Tube Hydroforming Prediction

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

    Johnson, Kenneth I.; Nguyen, Ba Nghiep; Davies, Richard W.

    2004-03-01

    This paper describes the development of a solution control method that tracks the stresses, strains and mechanical behavior of a tube during hydroforming to estimate the proper axial feed (end-feed) and internal pressure loads through time. The analysis uses the deformation theory of plasticity and Hill?s criterion to describe the plastic flow. Before yielding, the pressure and end-feed increments are estimated based on the initial tube geometry, elastic properties and yield stress. After yielding, the pressure increment is calculated based on the tube geometry at the previous solution increment and the current hoop stress increment. The end-feed increment is computedmore » from the increment of the axial plastic strain. Limiting conditions such as column buckling (of long tubes), local axi-symmetric wrinkling of shorter tubes, and bursting due to localized wall thinning are considered. The process control method has been implemented in the Marc finite element code. Hydroforming simulations using this process control method were conducted to predict the load histories for controlled expansion of 6061-T4 aluminum tubes within a conical die shape and under free hydroforming conditions. The predicted loading paths were transferred to the hydroforming equipment to form the conical and free-formed tube shapes. The model predictions and experimental results are compared for deformed shape, strains and the extent of forming at rupture.« less

  16. Wavelet Filtering to Reduce Conservatism in Aeroservoelastic Robust Stability Margins

    NASA Technical Reports Server (NTRS)

    Brenner, Marty; Lind, Rick

    1998-01-01

    Wavelet analysis for filtering and system identification was used to improve the estimation of aeroservoelastic stability margins. The conservatism of the robust stability margins was reduced with parametric and nonparametric time-frequency analysis of flight data in the model validation process. Nonparametric wavelet processing of data was used to reduce the effects of external desirableness and unmodeled dynamics. Parametric estimates of modal stability were also extracted using the wavelet transform. Computation of robust stability margins for stability boundary prediction depends on uncertainty descriptions derived from the data for model validation. F-18 high Alpha Research Vehicle aeroservoelastic flight test data demonstrated improved robust stability prediction by extension of the stability boundary beyond the flight regime.

  17. Cost-Effectiveness Analysis of Regorafenib for Metastatic Colorectal Cancer

    PubMed Central

    Goldstein, Daniel A.; Ahmad, Bilal B.; Chen, Qiushi; Ayer, Turgay; Howard, David H.; Lipscomb, Joseph; El-Rayes, Bassel F.; Flowers, Christopher R.

    2015-01-01

    Purpose Regorafenib is a standard-care option for treatment-refractory metastatic colorectal cancer that increases median overall survival by 6 weeks compared with placebo. Given this small incremental clinical benefit, we evaluated the cost-effectiveness of regorafenib in the third-line setting for patients with metastatic colorectal cancer from the US payer perspective. Methods We developed a Markov model to compare the cost and effectiveness of regorafenib with those of placebo in the third-line treatment of metastatic colorectal cancer. Health outcomes were measured in life-years and quality-adjusted life-years (QALYs). Drug costs were based on Medicare reimbursement rates in 2014. Model robustness was addressed in univariable and probabilistic sensitivity analyses. Results Regorafenib provided an additional 0.04 QALYs (0.13 life-years) at a cost of $40,000, resulting in an incremental cost-effectiveness ratio of $900,000 per QALY. The incremental cost-effectiveness ratio for regorafenib was > $550,000 per QALY in all of our univariable and probabilistic sensitivity analyses. Conclusion Regorafenib provides minimal incremental benefit at high incremental cost per QALY in the third-line management of metastatic colorectal cancer. The cost-effectiveness of regorafenib could be improved by the use of value-based pricing. PMID:26304904

  18. Comparative analysis of age dynamics of average values of body dimensions in children from birth to 7 years.

    PubMed

    Deryabin, Vasily E; Krans, Valentina M; Fedotova, Tatiana K

    2005-07-01

    Mean values of different body dimensions in different age cohorts of children make it possible to learn a lot about their dynamic changes. Their comparative analysis, as is usually practiced, in fact leads to a simple description of changes in measurement units (mm or cm) at the average level of some body dimension during a shorter or longer period of time. To estimate comparative intensity of the growth process of different body dimensions, the authors use the analogue of Mahalanobis distance, the so-called Kullback divergence (1967), which does not demand stability of dispersion or correlation coefficients of dimensions in compared cohorts of children. Most of the dimensions, excluding skinfolds, demonstrate growth dynamics with gradually reducing increments from birth to 7 years. Body length has the highest integrative increment, leg length about 94% of body length, body mass 77%, and trunk and extremities circumferences 56%. Skinfolds have a non-monotonic pattern of accumulated standardized increments with some increase until 1-2 years of age.

  19. Tolerance of image enhancement brightness and contrast in lateral cephalometric digital radiography for Steiner analysis

    NASA Astrophysics Data System (ADS)

    Rianti, R. A.; Priaminiarti, M.; Syahraini, S. I.

    2017-08-01

    Image enhancement brightness and contrast can be adjusted on lateral cephalometric digital radiographs to improve image quality and anatomic landmarks for measurement by Steiner analysis. To determine the limit value for adjustments of image enhancement brightness and contrast in lateral cephalometric digital radiography for Steiner analysis. Image enhancement brightness and contrast were adjusted on 100 lateral cephalometric radiography in 10-point increments (-30, -20, -10, 0, +10, +20, +30). Steiner analysis measurements were then performed by two observers. Reliabilities were tested by the Interclass Correlation Coefficient (ICC) and significance tested by ANOVA or the Kruskal Wallis test. No significant differences were detected in lateral cephalometric analysis measurements following adjustment of the image enhancement brightness and contrast. The limit value of adjustments of the image enhancement brightness and contrast associated with incremental 10-point changes (-30, -20, -10, 0, +10, +20, +30) does not affect the results of Steiner analysis.

  20. Sensitivity of finite helical axis parameters to temporally varying realistic motion utilizing an idealized knee model.

    PubMed

    Johnson, T S; Andriacchi, T P; Erdman, A G

    2004-01-01

    Various uses of the screw or helical axis have previously been reported in the literature in an attempt to quantify the complex displacements and coupled rotations of in vivo human knee kinematics. Multiple methods have been used by previous authors to calculate the axis parameters, and it has been theorized that the mathematical stability and accuracy of the finite helical axis (FHA) is highly dependent on experimental variability and rotation increment spacing between axis calculations. Previous research has not addressed the sensitivity of the FHA for true in vivo data collection, as required for gait laboratory analysis. This research presents a controlled series of experiments simulating continuous data collection as utilized in gait analysis to investigate the sensitivity of the three-dimensional finite screw axis parameters of rotation, displacement, orientation and location with regard to time step increment spacing, utilizing two different methods for spatial location. Six-degree-of-freedom motion parameters are measured for an idealized rigid body knee model that is constrained to a planar motion profile for the purposes of error analysis. The kinematic data are collected using a multicamera optoelectronic system combined with an error minimization algorithm known as the point cluster method. Rotation about the screw axis is seen to be repeatable, accurate and time step increment insensitive. Displacement along the axis is highly dependent on time step increment sizing, with smaller rotation angles between calculations producing more accuracy. Orientation of the axis in space is accurate with only a slight filtering effect noticed during motion reversal. Locating the screw axis by a projected point onto the screw axis from the mid-point of the finite displacement is found to be less sensitive to motion reversal than finding the intersection of the axis with a reference plane. A filtering effect of the spatial location parameters was noted for larger time step increments during periods of little or no rotation.

  1. Cost-Utility Analysis of Cochlear Implantation in Australian Adults.

    PubMed

    Foteff, Chris; Kennedy, Steven; Milton, Abul Hasnat; Deger, Melike; Payk, Florian; Sanderson, Georgina

    2016-06-01

    Sequential and simultaneous bilateral cochlear implants are emerging as appropriate treatment options for Australian adults with sensory deficits in both cochleae. Current funding of Australian public hospitals does not provide for simultaneous bilateral cochlear implantation (CI) as a separate surgical procedure. Previous cost-effectiveness studies of sequential and simultaneous bilateral CI assumed 100% of unilaterally treated patients' transition to a sequential bilateral CI. This assumption does not place cochlear implantation in the context of the generally treated population. When mutually exclusive treatment options exist, such as unilateral CI, sequential bilateral CI, and simultaneous bilateral CI, the mean costs of the treated populations are weighted in the calculation of incremental cost-utility ratios. The objective was to evaluate the cost-utility of bilateral hearing aids (HAs) compared with unilateral, sequential, and simultaneous bilateral CI in Australian adults with bilateral severe to profound sensorineural hearing loss. Cost-utility analysis of secondary sources input to a Markov model. Australian health care perspective, lifetime horizon with costs and outcomes discounted 5% annually. Bilateral HAs as treatment for bilateral severe to profound sensorineural hearing loss compared with unilateral, sequential, and simultaneous bilateral CI. Incremental costs per quality adjusted life year (AUD/QALY). When compared with bilateral hearing aids the incremental cost-utility ratio for the CI treatment population was AUD11,160/QALY. The incremental cost-utility ratio was weighted according to the number of patients treated unilaterally, sequentially, and simultaneously, as these were mutually exclusive treatment options. No peer-reviewed articles have reported the incremental analysis of cochlear implantation in a continuum of care for surgically treated populations with bilateral severe to profound sensorineural hearing loss. Unilateral, sequential, and simultaneous bilateral CI were cost-effective when compared with bilateral hearing aids. Technologies that reduce the total number of visits for a patient could introduce additional cost efficiencies into clinical practice.

  2. Cost-effectiveness of histamine receptor-2 antagonist versus proton pump inhibitor for stress ulcer prophylaxis in critically ill patients*.

    PubMed

    MacLaren, Robert; Campbell, Jon

    2014-04-01

    To examine the cost-effectiveness of using histamine receptor-2 antagonist or proton pump inhibitor for stress ulcer prophylaxis. Decision analysis model examining costs and effectiveness of using histamine receptor-2 antagonist or proton pump inhibitor for stress ulcer prophylaxis. Costs were expressed in 2012 U.S. dollars from the perspective of the institution and included drug regimens and the following outcomes: clinically significant stress-related mucosal bleed, ventilator-associated pneumonia, and Clostridium difficile infection. Effectiveness was the mortality risk associated with these outcomes and represented by survival. Costs, occurrence rates, and mortality probabilities were extracted from published data. A simulation model. A mixed adult ICU population. Histamine receptor-2 antagonist or proton pump inhibitor for 9 days of stress ulcer prophylaxis therapy. Output variables were expected costs, expected survival rates, incremental cost, and incremental survival rate. Univariate sensitivity analyses were conducted to determine the drivers of incremental cost and incremental survival. Probabilistic sensitivity analysis was conducted using second-order Monte Carlo simulation. For the base case analysis, the expected cost of providing stress ulcer prophylaxis was $6,707 with histamine receptor-2 antagonist and $7,802 with proton pump inhibitor, resulting in a cost saving of $1,095 with histamine receptor-2 antagonist. The associated mortality probabilities were 3.819% and 3.825%, respectively, resulting in an absolute survival benefit of 0.006% with histamine receptor-2 antagonist. The primary drivers of incremental cost and survival were the assumptions surrounding ventilator-associated pneumonia and bleed. The probabilities that histamine receptor-2 antagonist was less costly and provided favorable survival were 89.4% and 55.7%, respectively. A secondary analysis assuming equal rates of C. difficile infection showed a cost saving of $908 with histamine receptor-2 antagonists, but the survival benefit of 0.0167% favored proton pump inhibitors. Histamine receptor-2 antagonist therapy appears to reduce costs with survival benefit comparable to proton pump inhibitor therapy for stress ulcer prophylaxis. Ventilator-associated pneumonia and bleed are the variables most affecting these outcomes. The uncertainty in the findings justifies a prospective trial.

  3. Gingival microleakage of class V composite restorations with fiber inserts.

    PubMed

    Ahmed, Walaa; El-Badrawy, Wafa; Kulkarni, Gajanan; Prakki, Anuradha; El-Mowafy, Omar

    2013-07-01

    This study investigated the effect of different fiber inserts (glass and polyethylene), bonding agents, and resin composites on the gingival margin microleakage of class V composite restorations. Sixty premolars were sterilized and mounted in acrylic resin bases. Class V cavities were prepared buccally and lingually, 1 mm below the cementoenamel junction, comprising 12 groups (n = 10). In the experimental groups fiber inserts were cut and placed at the gingival seat, while the control groups had no inserts. Combinations of two composite materials, Filtek-Z250 and Filtek-LS (3M-ESPE), and four bonding agents, Clearfil SE bond (Kuraray) (C), Scotch Bond Multipurpose (3M-ESPE) (SB), Prime and Bond NT (Dentsply) (PB), and Filtek-LS (3M-ESPE) (LS) were used. Restorations were incrementally inserted and polymerized for 40s. Specimens were then stored in distilled water for 7 days and thermocycled for 500 cycles. Teeth surfaces were sealed with nail polish except for 1 mm around restoration margins and immersed in 2% red procion dye. Teeth were then sectioned buccolingually and dye penetration was assessed with five-point scale. Data were statistically-analyzed by Kruskal-Wallis, ANOVA and Tukey's tests (α = 5%). Mean microleakage scores varied from 0.40 (Groups C, C with polyethylene, LS, LS with polyethylene) to 1.50 (SB). Different bonding agents led to differences in microleakage scores where C and LS showed significantly lower microleakage than PB. SB had highest mean microleakage score, however, incorporation of fibers resulted in significant reduction in microleakage. Class V resin composite restorations bonded with a total-etch adhesive had a significant reduction in mean microleakage scores when glass or polyethylene fibers were placed at the gingival cavo-surface margin. In contrast, for two self-etch adhesive systems, the incorporation of fibers had no significant effect on mean microleakage scores.

  4. Effect of aluminum chloride hemostatic agent on microleakage of class V composite resin restorations bonded with all-in-one adhesive

    PubMed Central

    Mohammadi, Narmin; Bahari, Mahmood; Pournaghi-Azar, Fatemeh; Mozafari, Aysan

    2012-01-01

    Objectives: Since hemostatic agents can induce changes on enamel and dentin surfaces and influence composite resin adhesion, the aim of the present study was to evaluate the effect of the aluminum chloride hemostatic agent on the gingival margin microleakage of class V (Cl V) composite resin restorations bonded with all-in-one adhesive. Study design: Cl V cavities were prepared on the buccal surfaces of 60 sound bovine permanent incisors. Gingival margins of the cavities were placed 1.5 mm apical to the cemento-enamel junction (CEJ). The teeth were randomly divided into two groups of 30. In group 1, the cavities were restored without the application of a hemostatic agent; in group 2, the cavities were restored after the application of the hemostatic agent. In both groups all-in-one adhesive and Z250 composite resin were used to restore the cavities with the incremental technique. After finishing and polishing, the samples underwent a thermocycling procedure, followed by immersion in 2% basic fuschin solution for 24 hours. The samples were sectioned and gingival microleakage was evaluated under a stereomicroscope. The non-parametric Mann-Whitney U test was used to compare microleakage between the two groups. Statistical significance was defined at P<0.05. Results: A statistically significant difference was observed in microleakage between the two groups (P<0.001). Conclusions: Contamination of Cl V composite resin restorations bonded with all-in-one adhesive with aluminum chloride hemostatic agent significantly increases restoration gingival margin microleakage. Key words:All-in-one adhesive resin, composite resin restoration, hemostatic agent, microleakage. PMID:22322497

  5. Evaluation of marginal failures of dental composite restorations by acoustic emission analysis.

    PubMed

    Gu, Ja-Uk; Choi, Nak-Sam

    2013-01-01

    In this study, a nondestructive method based on acoustic emission (AE) analysis was developed to evaluate the marginal failure states of dental composite restorations. Three types of ring-shaped substrates, which were modeled after a Class I cavity, were prepared from polymethyl methacrylate, stainless steel, and human molar teeth. A bonding agent and a composite resin were applied to the ring-shaped substrates and cured by light exposure. At each time-interval measurement, the tooth substrate presented a higher number of AE hits than polymethyl methacrylate and steel substrates. Marginal disintegration estimations derived from cumulative AE hits and cumulative AE energy parameters showed that a signification portion of marginal gap formation was already realized within 1 min at the initial light-curing stage. Estimation based on cumulative AE energy gave a higher level of marginal failure than that based on AE hits. It was concluded that the AE analysis method developed in this study was a viable approach in predicting the clinical survival of dental composite restorations efficiently within a short test period.

  6. Street Sex Work: Re/Constructing Discourse from Margin to Center

    ERIC Educational Resources Information Center

    McCracken, Jill Linnette

    2009-01-01

    Newspaper media create interpretations of marginalized groups that require rhetorical analysis so that we can better understand these representations. This article focuses on how newspaper articles create interpretations of sex work that affect both the marginalized and mainstream communities. My ethnographic case study argues that the material…

  7. On Time Delay Margin Estimation for Adaptive Control and Optimal Control Modification

    NASA Technical Reports Server (NTRS)

    Nguyen, Nhan T.

    2011-01-01

    This paper presents methods for estimating time delay margin for adaptive control of input delay systems with almost linear structured uncertainty. The bounded linear stability analysis method seeks to represent an adaptive law by a locally bounded linear approximation within a small time window. The time delay margin of this input delay system represents a local stability measure and is computed analytically by three methods: Pade approximation, Lyapunov-Krasovskii method, and the matrix measure method. These methods are applied to the standard model-reference adaptive control, s-modification adaptive law, and optimal control modification adaptive law. The windowing analysis results in non-unique estimates of the time delay margin since it is dependent on the length of a time window and parameters which vary from one time window to the next. The optimal control modification adaptive law overcomes this limitation in that, as the adaptive gain tends to infinity and if the matched uncertainty is linear, then the closed-loop input delay system tends to a LTI system. A lower bound of the time delay margin of this system can then be estimated uniquely without the need for the windowing analysis. Simulation results demonstrates the feasibility of the bounded linear stability method for time delay margin estimation.

  8. Robust Stability Analysis of the Space Launch System Control Design: A Singular Value Approach

    NASA Technical Reports Server (NTRS)

    Pei, Jing; Newsome, Jerry R.

    2015-01-01

    Classical stability analysis consists of breaking the feedback loops one at a time and determining separately how much gain or phase variations would destabilize the stable nominal feedback system. For typical launch vehicle control design, classical control techniques are generally employed. In addition to stability margins, frequency domain Monte Carlo methods are used to evaluate the robustness of the design. However, such techniques were developed for Single-Input-Single-Output (SISO) systems and do not take into consideration the off-diagonal terms in the transfer function matrix of Multi-Input-Multi-Output (MIMO) systems. Robust stability analysis techniques such as H(sub infinity) and mu are applicable to MIMO systems but have not been adopted as standard practices within the launch vehicle controls community. This paper took advantage of a simple singular-value-based MIMO stability margin evaluation method based on work done by Mukhopadhyay and Newsom and applied it to the SLS high-fidelity dynamics model. The method computes a simultaneous multi-loop gain and phase margin that could be related back to classical margins. The results presented in this paper suggest that for the SLS system, traditional SISO stability margins are similar to the MIMO margins. This additional level of verification provides confidence in the robustness of the control design.

  9. 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.

  10. Bounded Linear Stability Analysis - A Time Delay Margin Estimation Approach for Adaptive Control

    NASA Technical Reports Server (NTRS)

    Nguyen, Nhan T.; Ishihara, Abraham K.; Krishnakumar, Kalmanje Srinlvas; Bakhtiari-Nejad, Maryam

    2009-01-01

    This paper presents a method for estimating time delay margin for model-reference adaptive control of systems with almost linear structured uncertainty. The bounded linear stability analysis method seeks to represent the conventional model-reference adaptive law by a locally bounded linear approximation within a small time window using the comparison lemma. The locally bounded linear approximation of the combined adaptive system is cast in a form of an input-time-delay differential equation over a small time window. The time delay margin of this system represents a local stability measure and is computed analytically by a matrix measure method, which provides a simple analytical technique for estimating an upper bound of time delay margin. Based on simulation results for a scalar model-reference adaptive control system, both the bounded linear stability method and the matrix measure method are seen to provide a reasonably accurate and yet not too conservative time delay margin estimation.

  11. Approach for Estimating Exposures and Incremental Health ...

    EPA Pesticide Factsheets

    Approach for Estimating Exposures and Incremental Health Effects from Lead During Renovation, Repair, and Painting Activities in Public and Commercial Buildings” (Technical Approach Document). Also available for public review and comment are two supplementary documents: the detailed appendices for the Technical Approach Document and a supplementary report entitled “Developing a Concentration-Response Function for Pb Exposure and Cardiovascular Disease-Related Mortality.” Together, these documents describes an analysis for estimating exposures and incremental health effects created by renovations of public and commercial buildings (P&CBs). This analysis could be used to identify and evaluate hazards from renovation, repair, and painting activities in P&CBs. A general overview of how this analysis can be used to inform EPA’s hazard finding is described in the Framework document that was previously made available for public comment (79 FR 31072; FRL9910-44). The analysis can be used in any proposed rulemaking to estimate the reduction in deleterious health effects that would result from any proposed regulatory requirements to mitigate exposure from P&CB renovation activities. The Technical Approach Document describes in detail how the analyses under this approach have been performed and presents the results – expected changes in blood lead levels and health effects due to lead exposure from renovation activities.

  12. Meta-Analysis of Incremental Rehearsal Using Phi Coefficients to Compare Single-Case and Group Designs

    ERIC Educational Resources Information Center

    Burns, Matthew K.; Zaslofsky, Anne F.; Kanive, Rebecca; Parker, David C.

    2012-01-01

    The current study meta-analyzed single-case design (SCD) and group research regarding incremental rehearsal (IR). We used phi to meta-analyze data from 19 IR studies. Data from the SCD studies resulted in a nonoverlap of all pairs (NAP) score of 98.9% (95% CI = 97.6-100%), which resulted in a weighted phi of 0.77 (95% CI = 0.69-0.83). The group…

  13. Supplier Relationship Management at Army Life Cycle Management Commands: Gap Analysis of Best Practices

    DTIC Science & Technology

    2012-01-01

    307–308) define kaizen as “continuous, incremental improvement of an activity to create more value with less muda.” They define muda as “any activity...approaches, kaizen events, Six Sigma, total quality management (TQM) for continuous improvement, kaikaku,6 process reengineering for discontinuous...them fix problems and develop capabilities. These efforts may include kaizen (i.e., continuous, incremental improvement) events, process mapping, work

  14. OCT structure, COB location and magmatic type of the SE Brazilian & S Angolan margins from integrated quantitative analysis of deep seismic reflection and gravity anomaly data

    NASA Astrophysics Data System (ADS)

    Cowie, L.; Kusznir, N. J.; Horn, B.

    2013-12-01

    Knowledge of ocean-continent transition (OCT) structure, continent-ocean boundary (COB) location and magmatic type are of critical importance for understanding rifted continental margin formation processes and in evaluating petroleum systems in deep-water frontier oil and gas exploration. The OCT structure, COB location and magmatic type of the SE Brazilian and S Angolan rifted continental margins are much debated; exhumed and serpentinised mantle have been reported at these margins. Integrated quantitative analysis using deep seismic reflection data and gravity inversion have been used to determine OCT structure, COB location and magmatic type for the SE Brazilian and S Angolan margins. Gravity inversion has been used to determine Moho depth, crustal basement thickness and continental lithosphere thinning. Residual Depth Anomaly (RDA) analysis has been used to investigate OCT bathymetric anomalies with respect to expected oceanic bathymetries and subsidence analysis has been used to determine the distribution of continental lithosphere thinning. These techniques have been validated on the Iberian margin for profiles IAM9 and ISE-01. In addition a joint inversion technique using deep seismic reflection and gravity anomaly data has been applied to the ION-GXT BS1-575 SE Brazil and ION-GXT CS1-2400 S Angola. The joint inversion method solves for coincident seismic and gravity Moho in the time domain and calculates the lateral variations in crustal basement densities and velocities along profile. Gravity inversion, RDA and subsidence analysis along the S Angolan ION-GXT CS1-2400 profile has been used to determine OCT structure and COB location. Analysis suggests that exhumed mantle, corresponding to a magma poor margin, is absent beneath the allochthonous salt. The thickness of earliest oceanic crust, derived from gravity and deep seismic reflection data is approximately 7km. The joint inversion predicts crustal basement densities and seismic velocities which are slightly less than expected for 'normal' oceanic crust. The difference between the sediment corrected RDA and that predicted from gravity inversion crustal thickness variation implies that this margin is experiencing ~300m of anomalous uplift attributed to mantle dynamic uplift. Gravity inversion, RDA and subsidence analysis have also been used to determine OCT structure and COB location along the ION-GXT BS1-575 profile, crossing the Sao Paulo Plateau and Florianopolis Ridge of the SE Brazilian margin. Gravity inversion, RDA and subsidence analysis predict the COB to be located SE of the Florianopolis Ridge. Analysis shows no evidence for exhumed mantle on this margin profile. The joint inversion technique predicts normal oceanic basement seismic velocities and densities and beneath the Sao Paulo Plateau and Florianopolis Ridge predicts crustal basement thicknesses between 10-15km. The Sao Paulo Plateau and Florianopolis Ridge are separated by a thin region of crustal basement beneath the salt interpreted as a regional transtensional structure. Sediment corrected RDAs and gravity derived 'synthetic' RDAs are of a similar magnitude on oceanic crust, implying negligible mantle dynamic topography.

  15. CO2 laser versus cold steel margin analysis following endoscopic excision of glottic cancer

    PubMed Central

    2014-01-01

    Objective To compare the suitability of CO2 laser with steel instruments for margin excision in transoral laser microsurgery. Methods Prospective randomized blinded study. Patients with glottic cancer undergoing laser resection were randomized to margin excision by either steel instruments or CO2 laser. Margins were analyzed for size, interpretability and degree of artifact by a pathologist who was blinded to technique. Results 45 patients were enrolled in the study with 226 total margins taken. 39 margins taken by laser had marked artifact and 0 were uninterpretable. 20 margins taken by steel instruments had marked artifact, and 2 were uninterpretable. Controlling for margin size, the laser technique was associated with increasing degrees of margin artifact (p = 0.210), but there was no difference in crude rates of uninterpretability (p = 0.24). Conclusion Laser margin excision is associated with a greater degree of artifact than steel instrument excision, but was not associated with higher rate of uninterpretability. PMID:24502856

  16. A primer on marginal effects-part II: health services research applications.

    PubMed

    Onukwugha, E; Bergtold, J; Jain, R

    2015-02-01

    Marginal analysis evaluates changes in a regression function associated with a unit change in a relevant variable. The primary statistic of marginal analysis is the marginal effect (ME). The ME facilitates the examination of outcomes for defined patient profiles or individuals while measuring the change in original units (e.g., costs, probabilities). The ME has a long history in economics; however, it is not widely used in health services research despite its flexibility and ability to provide unique insights. This article, the second in a two-part series, discusses practical issues that arise in the estimation and interpretation of the ME for a variety of regression models often used in health services research. Part one provided an overview of prior studies discussing ME followed by derivation of ME formulas for various regression models relevant for health services research studies examining costs and utilization. The current article illustrates the calculation and interpretation of ME in practice and discusses practical issues that arise during the implementation, including: understanding differences between software packages in terms of functionality available for calculating the ME and its confidence interval, interpretation of average marginal effect versus marginal effect at the mean, and the difference between ME and relative effects (e.g., odds ratio). Programming code to calculate ME using SAS, STATA, LIMDEP, and MATLAB are also provided. The illustration, discussion, and application of ME in this two-part series support the conduct of future studies applying the concept of marginal analysis.

  17. Implicit personality theory in evaluation of brand extensions.

    PubMed

    Flaherty, K E; Pappas, J M

    2000-06-01

    Transference, the extent to which consumers transfer their opinions of a parent brand to a new extension, is critical to the success of any brand-extension strategy. Past research has shown that transference is a complex process that varies among persons depending upon an implicit personality theory, entity versus incremental. In a laboratory experiment analysis of ratings for 100 21-yr.-old undergraduates of attitude, perceived fit and risk, prior product involvement, and implicit personality theory (entity versus incremental) the influence of consumers' implicit personality theory on transference was considered within the brand-extension context. As expected, the amount of transference differed between those espousing entity and incremental theories. "Entity theorists" were much more likely to transfer feelings associated with the parent brand to the new extension than were "incremental theorists" who did not rely on prior brand information when forming evaluations of a new extension. This effect did not occur when perceived fit between the parent brand and the extension was high.

  18. The cost effectiveness of intracyctoplasmic sperm injection (ICSI).

    PubMed

    Hollingsworth, Bruce; Harris, Anthony; Mortimer, Duncan

    2007-12-01

    To estimate the incremental cost effectiveness of ICSI, and total costs for the population of Australia. Treatment effects for three patient groups were drawn from a published systematic review and meta-analysis of trials comparing fertilisation outcomes for ICSI. Incremental costs derived from resource-based costing of ICSI and existing practice comparators for each patient group. Incremental cost per live birth for patients unsuited to IVF is estimated between A$8,500 and 13,400. For the subnormal semen indication, cost per live birth could be as low as A$3,600, but in the worst case scenario, there would just be additional incremental costs of A$600 per procedure. Multiplying out the additional costs of ICSI over the relevant target populations in Australia gives potential total financial implications of over A$31 million per annum. While there are additional benefits from ICSI procedure, particularly for those with subnormal sperm, the additional cost for the health care system is substantial.

  19. The Potential Impact of CO2 and Air Temperature Increases on Krummholz's Transformation into Arborescent Form in the Southern Siberian Mountains

    NASA Technical Reports Server (NTRS)

    Kharuk, V. I.; Dvinskaya, M. L.; Im, S. T.; Ranson, K. J.

    2011-01-01

    Trees in the southern Siberian Mountains forest-tundra ecotone have considerably increased their radial and apical growth increments during the last few decades. This leads to the widespread vertical transformation of mat and prostrate krummholz forms of larch (Larix sibirica Ledeb) and Siberian pine (Pinus sibirica Du Tour). An analysis of the radial growth increments showed that these transformations began in the mid-1980s. Larch showed a greater resistance to the harsh alpine environment and attained a vertical growth form in areas where Siberian pine is still krummholz. Upper larch treeline is about 10 m higher than Siberian pine treeline. Observed apical and radial growth increment increases were correlated with CO2 concentration (r = 0.83-0.87), summer temperatures (r = 0.55-0.64), and "cold period" (i.e. September-May) air temperatures (r = 0.36-0.37). Positive correlation between growth increments and winter precipitation was attributed to snow cover protection for trees during wintertime.

  20. Effect of resealing on microleakage of resin composite restorations in relationship to margin design and composite type

    PubMed Central

    Antonson, Sibel A.; Yazici, A. Ruya; Okte, Zeynep; Villalta, Patricia; Antonson, Donald E.; Hardigan, Patrick C.

    2012-01-01

    Objective: To determine the relationship between margin preparation design and resin-composite type on microleakage with or without re-application of surface-penetrating sealant. Methods: Class-I resin-composite restorations were completed for 128 extracted human molars. Half of the margins were beveled, the other half, butt-joint. Half of each group was restored with Filtek-Supreme (FS), the other half with Esthet-X (EX) using their respective adhesive systems. Margins were etched and sealed with a surface-penetrating sealant, Fortify. The samples were stored in water 24h, and thermocycled (5,000 cycles, 5°C–55°C). Then, samples were abraded using a toothbrush machine (6,000 strokes). Half of the restorations from each sealant group (n=16) were resealed, and the other half had no further treatment. Thermocycling and tooth brushing were repeated. The samples were sealed with nail polish, immersed in methylene-blue for 8h, sectioned, and magnified digital photographs were taken. Three examiners assessed dye penetration. A 2×2×2 multi-layered Chi-Square analysis, using Cochran-Mantel-Haenszel test was conducted for statistical analysis. Results: No difference was observed between sealed and resealed FS and EX restorations with butt-joint margins. In beveled margins, resealing caused significantly less microleakage (P<.01). No differences were found between restorations either sealed or resealed with bevel margins. In butt-joint margins, at the leakage level deeper than 2/3 of the preparation depth, resealed FS showed less microleakage than EX resealed restorations (P<.01). Conclusion: Resealing reduced microleakage in bevel margins, however, in butt-joint margins resealing did not affect the leakage. A significant statistical relationship exists between and within resealing, margin preparation design, type of composite, and microleakage. PMID:23077418

  1. Optimum Component Design in N-Stage Series Systems to Maximize the Reliability Under Budget Constraint

    DTIC Science & Technology

    2003-03-01

    27 2.8.5 Marginal Analysis Method...Figure 11 Improved Configuration of Figure 10; Increases Basic System Reliability..... 26 Figure 12 Example of marginal analysis ...View of Main Book of Software ............................................................... 51 Figure 20 The View of Data Worksheet

  2. Estimation Of TMDLs And Margin Of Safety Under Conditions Of Uncertainty

    EPA Science Inventory

    In TMDL development, an adequate margin of safety (MOS) is required in the calculation process to provide a cushion needed because of uncertainties in the data and analysis. Current practices, however, rarely factor analysis' uncertainty in TMDL development and the MOS is largel...

  3. Metabolic syndrome and the risk of adverse cardiovascular events after an acute coronary syndrome.

    PubMed

    Cavallari, Ilaria; Cannon, Christopher P; Braunwald, Eugene; Goodrich, Erica L; Im, KyungAh; Lukas, Mary Ann; O'Donoghue, Michelle L

    2018-05-01

    Background The incremental prognostic value of assessing the metabolic syndrome has been disputed. Little is known regarding its prognostic value in patients after an acute coronary syndrome. Design and methods The presence of metabolic syndrome (2005 International Diabetes Federation) was assessed at baseline in SOLID-TIMI 52, a trial of patients within 30 days of acute coronary syndrome (median follow-up 2.5 years). The primary endpoint was major coronary events (coronary heart disease death, myocardial infarction or urgent coronary revascularization). Results At baseline, 61.6% ( n = 7537) of patients met the definition of metabolic syndrome, 34.7% (n = 4247) had diabetes and 29.3% had both ( n = 3584). The presence of metabolic syndrome was associated with increased risk of major coronary events (adjusted hazard ratio (adjHR) 1.29, p < 0.0001) and recurrent myocardial infarction (adjHR 1.30, p < 0.0001). Of the individual components of the definition, only diabetes (adjHR 1.48, p < 0.0001) or impaired fasting glucose (adjHR 1.21, p = 0.002) and hypertension (adjHR 1.46, p < 0.0001) were associated with the risk of major coronary events. In patients without diabetes, metabolic syndrome was numerically but not significantly associated with the risk of major coronary events (adjHR 1.13, p = 0.06). Conversely, diabetes was a strong independent predictor of major coronary events in the absence of metabolic syndrome (adjHR 1.57, p < 0.0001). The presence of both diabetes and metabolic syndrome identified patients at highest risk of adverse outcomes but the incremental value of metabolic syndrome was not significant relative to diabetes alone (adjHR 1.07, p = 0.54). Conclusions After acute coronary syndrome, diabetes is a strong and independent predictor of adverse outcomes. Assessment of the metabolic syndrome provides only marginal incremental value once the presence or absence of diabetes is established.

  4. Is Patent “Evergreening” Restricting Access to Medicine/Device Combination Products?

    PubMed Central

    Beall, Reed F.; Nickerson, Jason W.; Kaplan, Warren A.; Attaran, Amir

    2016-01-01

    Background Not all new drug products are truly new. Some are the result of marginal innovation and incremental patenting of existing products, but in such a way that confers no major therapeutic improvement. This phenomenon, pejoratively known as “evergreening”, can allow manufacturers to preserve market exclusivity, but without significantly bettering the standard of care. Other studies speculate that evergreening is especially problematic for medicine/device combination products, because patents on the device component may outlast expired patents on the medicine component, and thereby keep competing, possibly less-expensive generic products off the market. Materials and Methods We focused on four common conditions that are often treated by medicine/device product combinations: asthma and chronic obstructive pulmonary disease (COPD), diabetes, and severe allergic reactions. The patent data for a sample of such products (n = 49) for treating these conditions was extracted from the United States Food and Drug Administration’s Orange Book. Additional patent-related data (abstracts, claims, etc) were retrieved using LexisNexis TotalPatent. Comparisons were then made between each product’s device patents and medicine patents. Results Unexpired device patents exist for 90 percent of the 49 medicine/device product combinations studied, and were the only sort of unexpired patent for 14 products. Overall, 55 percent of the 235 patents found by our study were device patents. Comparing the last-to-expire device patent to that of the last-to-expire active ingredient patent, the median additional years of patent protection afforded by device patents was 4.7 years (range: 1.3–15.2 years). Conclusion Incremental, patentable innovation in devices to extend the overall patent protection of medicine/device product combinations is very common. Whether this constitutes “evergreening” depends on whether these incremental innovations and the years of extra patent protection they confer are proportionately matched by therapeutic improvements in the standard of care, which is highly debatable. PMID:26910128

  5. The value of male human papillomavirus vaccination in preventing cervical cancer and genital warts in a low-resource setting.

    PubMed

    Sharma, M; Sy, S; Kim, J J

    2016-05-01

    To estimate health benefits and incremental cost-effectiveness of human papillomavirus (HPV) vaccination of pre-adolescent boys and girls compared with girls alone for preventing cervical cancer and genital warts. Model-based economic evaluation. Southern Vietnam. Males and females aged ≥9 years. We simulated dynamic HPV transmission to estimate cervical cancer and genital warts cases. Models were calibrated to epidemiological data from south Vietnam. Incremental cost-effectiveness ratios (ICERs): cost per quality-adjusted life-year (QALY). Vaccinating girls alone was associated with reductions in lifetime cervical cancer risk ranging from 20 to 56.9% as coverage varied from 25 to 90%. Adding boys to the vaccination programme yielded marginal incremental benefits (≤3.6% higher absolute cervical cancer risk reduction), compared with vaccinating girls alone at all coverages. At ≤25 international dollars (I$) per vaccinated adolescent (I$5 per dose), HPV vaccination of boys was below the threshold of Vietnam's per-capita GDP (I$2800), with ICERs ranging from I$734 per QALY at 25% coverage to I$2064 per QALY for 90% coverage. Including health benefits from averting genital warts yielded more favourable ICERs, and vaccination of boys at I$10/dose became cost-effective at or below 75% coverage. Using a lower cost-effectiveness threshold of 50% of Vietnam's GDP (I$1400), vaccinating boys was no longer attractive at costs above I$5 per dose regardless of coverage. Vaccination of boys may be cost-effective at low vaccine costs, but provides little benefit over vaccinating girls only. Focusing on achieving high vaccine coverage of girls may be more efficient for southern Vietnam and similar low-resource settings. Limited cervical cancer reduction from including boys in HPV vaccination of girls in low-resource settings. © 2015 Royal College of Obstetricians and Gynaecologists.

  6. Is Patent "Evergreening" Restricting Access to Medicine/Device Combination Products?

    PubMed

    Beall, Reed F; Nickerson, Jason W; Kaplan, Warren A; Attaran, Amir

    2016-01-01

    Not all new drug products are truly new. Some are the result of marginal innovation and incremental patenting of existing products, but in such a way that confers no major therapeutic improvement. This phenomenon, pejoratively known as "evergreening", can allow manufacturers to preserve market exclusivity, but without significantly bettering the standard of care. Other studies speculate that evergreening is especially problematic for medicine/device combination products, because patents on the device component may outlast expired patents on the medicine component, and thereby keep competing, possibly less-expensive generic products off the market. We focused on four common conditions that are often treated by medicine/device product combinations: asthma and chronic obstructive pulmonary disease (COPD), diabetes, and severe allergic reactions. The patent data for a sample of such products (n = 49) for treating these conditions was extracted from the United States Food and Drug Administration's Orange Book. Additional patent-related data (abstracts, claims, etc) were retrieved using LexisNexis TotalPatent. Comparisons were then made between each product's device patents and medicine patents. Unexpired device patents exist for 90 percent of the 49 medicine/device product combinations studied, and were the only sort of unexpired patent for 14 products. Overall, 55 percent of the 235 patents found by our study were device patents. Comparing the last-to-expire device patent to that of the last-to-expire active ingredient patent, the median additional years of patent protection afforded by device patents was 4.7 years (range: 1.3-15.2 years). Incremental, patentable innovation in devices to extend the overall patent protection of medicine/device product combinations is very common. Whether this constitutes "evergreening" depends on whether these incremental innovations and the years of extra patent protection they confer are proportionately matched by therapeutic improvements in the standard of care, which is highly debatable.

  7. Methodology for sensitivity analysis, approximate analysis, and design optimization in CFD for multidisciplinary applications

    NASA Technical Reports Server (NTRS)

    Taylor, Arthur C., III; Hou, Gene W.

    1993-01-01

    In this study involving advanced fluid flow codes, an incremental iterative formulation (also known as the delta or correction form) together with the well-known spatially-split approximate factorization algorithm, is presented for solving the very large sparse systems of linear equations which are associated with aerodynamic sensitivity analysis. For smaller 2D problems, a direct method can be applied to solve these linear equations in either the standard or the incremental form, in which case the two are equivalent. Iterative methods are needed for larger 2D and future 3D applications, however, because direct methods require much more computer memory than is currently available. Iterative methods for solving these equations in the standard form are generally unsatisfactory due to an ill-conditioning of the coefficient matrix; this problem can be overcome when these equations are cast in the incremental form. These and other benefits are discussed. The methodology is successfully implemented and tested in 2D using an upwind, cell-centered, finite volume formulation applied to the thin-layer Navier-Stokes equations. Results are presented for two sample airfoil problems: (1) subsonic low Reynolds number laminar flow; and (2) transonic high Reynolds number turbulent flow.

  8. Evaluation of the marginal fit of single-unit, complete-coverage ceramic restorations fabricated after digital and conventional impressions: A systematic review and meta-analysis.

    PubMed

    Tsirogiannis, Panagiotis; Reissmann, Daniel R; Heydecke, Guido

    2016-09-01

    In existing published reports, some studies indicate the superiority of digital impression systems in terms of the marginal accuracy of ceramic restorations, whereas others show that the conventional method provides restorations with better marginal fit than fully digital fabrication. Which impression method provides the lowest mean values for marginal adaptation is inconclusive. The findings from those studies cannot be easily generalized, and in vivo studies that could provide valid and meaningful information are limited in the existing publications. The purpose of this study was to systematically review existing reports and evaluate the marginal fit of ceramic single-tooth restorations after either digital or conventional impression methods by combining the available evidence in a meta-analysis. The search strategy for this systematic review of the publications was based on a Population, Intervention, Comparison, and Outcome (PICO) framework. For the statistical analysis, the mean marginal fit values of each study were extracted and categorized according to the impression method to calculate the mean value, together with the 95% confidence intervals (CI) of each category, and to evaluate the impact of each impression method on the marginal adaptation by comparing digital and conventional techniques separately for in vitro and in vivo studies. Twelve studies were included in the meta-analysis from the 63 identified records after database searching. For the in vitro studies, where ceramic restorations were fabricated after conventional impressions, the mean value of the marginal fit was 58.9 μm (95% CI: 41.1-76.7 μm), whereas after digital impressions, it was 63.3 μm (95% CI: 50.5-76.0 μm). In the in vivo studies, the mean marginal discrepancy of the restorations after digital impressions was 56.1 μm (95% CI: 46.3-65.8 μm), whereas after conventional impressions, it was 79.2 μm (95% CI: 59.6-98.9 μm) No significant difference was observed regarding the marginal discrepancy of single-unit ceramic restorations fabricated after digital or conventional impressions. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  9. "Doing School": A New Unit of Analysis for Schools Serving Marginalized Students

    ERIC Educational Resources Information Center

    Atkinson, Helen

    2009-01-01

    This study asserts a new unit of analysis for school reform that goes beyond the mental representations of individuals, beyond the isolated lesson, and beyond the confines of a school building. I argue that the special case of expanding time and space as a method of engagement for marginalized students requires that the unit of analysis change to…

  10. 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.

  11. Profitability analysis in the hospital industry.

    PubMed Central

    Cleverley, W O

    1978-01-01

    Measures of marginal profit are derived for the two payment classes--cost payers and charge payers--that the hospital industry must consider in profitability analysis, i.e., prediction of the excess of revenue over expenses. Two indexes of profitability, use when payment mix is constant and when it is nonconstant, respectively, are derived from the two marginal profit measures, and one of them is shown to be a modification of the contribution margin, the conventional measure of profitability used in general industry. All three measures--the contribution margin and the two new indexes of profitability--are used to estimate changes in net income resulting from changes in patient volume with and without accompanying changes in payment mix. The conventional measure yields large overestimates of expected excess revenue. PMID:632101

  12. TU-AB-303-06: Does Online Adaptive Radiation Therapy Mean Zero Margin for Intermediate-Risk Prostate Cancer? An Intra-Fractional Seminal Vesicles Motion Analysis

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

    Sheng, Y; Li, T; Lee, W

    Purpose: To provide benchmark for seminal vesicles (SVs) margin selection to account for intra-fractional motion; and to investigate the effectiveness of two motion surrogates in predicting intra-fractional SV underdosage. Methods: 9 prostate SBRT patients were studied; each has five pairs of pre-treatment and post-treatment cone-beam CTs (CBCTs). Each pair of CBCTs was registered based on fiducial markers in the prostate. To provide “ground truth” for coverage evaluation, all pre-treatment SVs were expanded with isotropic margin of 1,2,3,5 and 8mm, and their overlap with post-treatment SVs were used to quantify intra-fractional coverage. Two commonly used motion surrogates, the center-of-mass (COM) andmore » the border of contour (the most distal points in SI/AP/LR directions) were evaluated using Receiver-Operating Characteristic (ROC) analyses for predicting SV underdosage due to intra-fractional motion. Action threshold of determining underdosage for each surrogate was calculated by selecting the optimal balancing between sensitivity and specificity. For comparison, margin for each surrogate was also calculated based on traditional margin recipe. Results: 90% post-treatment SV coverage can be achieved in 47%, 82%, 91%, 98% and 98% fractions for 1,2,3,5 and 8mm margins. 3mm margin ensured the 90% intra-fractional SV coverage in 90% fractions when prostate was aligned. The ROC analysis indicated the AUC for COM and border were 0.88 and 0.72. The underdosage threshold was 2.9mm for COM and 4.1mm for border. The Van Herk’s margin recipe recommended 0.5, 0 and 1.8mm margin in LR, AP and SI direction based on COM and for border, the corresponding margin was 2.1, 4.5 and 3mm. Conclusion: 3mm isotropic margin is the minimum required to mitigate the intra-fractional SV motion when prostate is aligned. ROC analysis reveals that both COM and border are acceptable predictors for SV underdosage with 2.9mm and 4.1mm action threshold. Traditional margin calculation is less reliable for this application. This work is partially supported a master research grant from Varian Medical Systems.« less

  13. Mexican Americans in Higher Education: Cultural Adaptation and Marginalization as Predictors of College Persistence Intentions and Life Satisfaction

    ERIC Educational Resources Information Center

    Ojeda, Lizette; Castillo, Linda G.; Rosales Meza, Rocío; Piña-Watson, Brandy

    2014-01-01

    This study examined how college persistence intentions and life satisfaction influenced by acculturation, enculturation, White marginalization, and Mexican American marginalization among 515 Mexican American college students. The utility of a path analysis model was supported. Enculturation positively predicted persistence and life satisfaction.…

  14. 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

  15. OCT structure, COB location and magmatic type of the S Angolan & SE Brazilian margins from integrated quantitative analysis of deep seismic reflection and gravity anomaly data

    NASA Astrophysics Data System (ADS)

    Cowie, Leanne; Kusznir, Nick; Horn, Brian

    2014-05-01

    Integrated quantitative analysis using deep seismic reflection data and gravity inversion have been applied to the S Angolan and SE Brazilian margins to determine OCT structure, COB location and magmatic type. Knowledge of these margin parameters are of critical importance for understanding rifted continental margin formation processes and in evaluating petroleum systems in deep-water frontier oil and gas exploration. The OCT structure, COB location and magmatic type of the S Angolan and SE Brazilian rifted continental margins are much debated; exhumed and serpentinised mantle have been reported at these margins. Gravity anomaly inversion, incorporating a lithosphere thermal gravity anomaly correction, has been used to determine Moho depth, crustal basement thickness and continental lithosphere thinning. Residual Depth Anomaly (RDA) analysis has been used to investigate OCT bathymetric anomalies with respect to expected oceanic bathymetries and subsidence analysis has been used to determine the distribution of continental lithosphere thinning. These techniques have been validated for profiles Lusigal 12 and ISE-01 on the Iberian margin. In addition a joint inversion technique using deep seismic reflection and gravity anomaly data has been applied to the ION-GXT BS1-575 SE Brazil and ION-GXT CS1-2400 S Angola deep seismic reflection lines. The joint inversion method solves for coincident seismic and gravity Moho in the time domain and calculates the lateral variations in crustal basement densities and velocities along the seismic profiles. Gravity inversion, RDA and subsidence analysis along the ION-GXT BS1-575 profile, which crosses the Sao Paulo Plateau and Florianopolis Ridge of the SE Brazilian margin, predict the COB to be located SE of the Florianopolis Ridge. Integrated quantitative analysis shows no evidence for exhumed mantle on this margin profile. The joint inversion technique predicts oceanic crustal thicknesses of between 7 and 8 km thickness with normal oceanic basement seismic velocities and densities. Beneath the Sao Paulo Plateau and Florianopolis Ridge, joint inversion predicts crustal basement thicknesses between 10-15km with high values of basement density and seismic velocities under the Sao Paulo Plateau which are interpreted as indicating a significant magmatic component within the crustal basement. The Sao Paulo Plateau and Florianopolis Ridge are separated by a thin region of crustal basement beneath the salt interpreted as a regional transtensional structure. Sediment corrected RDAs and gravity derived "synthetic" RDAs are of a similar magnitude on oceanic crust, implying negligible mantle dynamic topography. Gravity inversion, RDA and subsidence analysis along the S Angolan ION-GXT CS1-2400 profile suggests that exhumed mantle, corresponding to a magma poor margin, is absent..The thickness of earliest oceanic crust, derived from gravity and deep seismic reflection data, is approximately 7km consistent with the global average oceanic crustal thicknesses. The joint inversion predicts a small difference between oceanic and continental crustal basement density and seismic velocity, with the change in basement density and velocity corresponding to the COB independently determined from RDA and subsidence analysis. The difference between the sediment corrected RDA and that predicted from gravity inversion crustal thickness variation implies that this margin is experiencing approximately 500m of anomalous uplift attributed to mantle dynamic uplift.

  16. 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.

  17. Cost-effectiveness of available treatment options for patients suffering from severe COPD in the UK: a fully incremental analysis.

    PubMed

    Hertel, Nadine; Kotchie, Robert W; Samyshkin, Yevgeniy; Radford, Matthew; Humphreys, Samantha; Jameson, Kevin

    2012-01-01

    Frequent exacerbations which are both costly and potentially life-threatening are a major concern to patients with chronic obstructive pulmonary disease (COPD), despite the availability of several treatment options. This study aimed to assess the lifetime costs and outcomes associated with alternative treatment regimens for patients with severe COPD in the UK setting. A Markov cohort model was developed to predict lifetime costs, outcomes, and cost-effectiveness of various combinations of a long-acting muscarinic antagonist (LAMA), a long-acting beta agonist (LABA), an inhaled corticosteroid (ICS), and roflumilast in a fully incremental analysis. Patients willing and able to take ICS, and those refusing or intolerant to ICS were analyzed separately. Efficacy was expressed as relative rate ratios of COPD exacerbation associated with alternative treatment regimens, taken from a mixed treatment comparison. The analysis was conducted from the UK National Health Service (NHS) perspective. Parameter uncertainty was explored using one-way and probabilistic sensitivity analysis. Based on the results of the fully incremental analysis a cost-effectiveness frontier was determined, indicating those treatment regimens which represent the most cost-effective use of NHS resources. For ICS-tolerant patients the cost-effectiveness frontier suggested LAMA as initial treatment. Where patients continue to exacerbate and additional therapy is required, LAMA + LABA/ICS can be a cost-effective option, followed by LAMA + LABA/ICS + roflumilast (incremental cost-effectiveness ratio [ICER] versus LAMA + LABA/ICS: £16,566 per quality-adjusted life-year [QALY] gained). The ICER in ICS-intolerant patients, comparing LAMA + LABA + roflumilast versus LAMA + LABA, was £13,764/QALY gained. The relative rate ratio of exacerbations was identified as the primary driver of cost-effectiveness. The treatment algorithm recommended in UK clinical practice represents a cost-effective approach for the management of COPD. The addition of roflumilast to the standard of care regimens is a clinical and cost-effective treatment option for patients with severe COPD, who continue to exacerbate despite existing bronchodilator therapy.

  18. An indirect comparison and cost per responder analysis of adalimumab, methotrexate and apremilast in the treatment of methotrexate-naïve patients with psoriatic arthritis.

    PubMed

    Betts, Keith A; Griffith, Jenny; Friedman, Alan; Zhou, Zheng-Yi; Signorovitch, James E; Ganguli, Arijit

    2016-01-01

    Apremilast was recently approved for the treatment of active psoriatic arthritis (PsA). However, no studies compare apremilast with methotrexate or biologic therapies, so its relative comparative efficacy remains unknown. This study compared the response rates and incremental costs per responder associated with methotrexate, apremilast, and biologics for the treatment of active PsA. A systematic literature review was performed to identify phase 3 randomized controlled clinical trials of approved biologics, methotrexate, and apremilast in the methotrexate-naïve PsA population. Using Bayesian methods, a network meta-analysis was conducted to indirectly compare rates of achieving a ≥20% improvement in American College of Rheumatology component scores (ACR20). The number needed to treat (NNT) and the incremental costs per ACR20 responder (2014 US$) relative to placebo were estimated for each of the therapies. Three trials (MIPA for methotrexate, PALACE-4 for apremilast, and ADEPT for adalimumab) met all inclusion criteria. The NNTs relative to placebo were 2.63 for adalimumab, 6.69 for apremilast, and 8.31 for methotrexate. Among methotrexate-naïve PsA patients, the 16 week incremental costs per ACR20 responder were $3622 for methotrexate, $26,316 for adalimumab, and $45,808 for apremilast. The incremental costs per ACR20 responder were $222,488 for apremilast vs. methotrexate. Among methotrexate-naive PsA patients, adalimumab was found to have the lowest NNT for one additional ACR20 response and methotrexate was found to have the lowest incremental costs per ACR20 responder. There was no statistical evidence of greater efficacy for apremilast vs. methotrexate. A head-to-head trial between apremilast and methotrexate is recommended to confirm this finding.

  19. Cost-effectiveness analysis of low-molecular-weight heparin versus aspirin thromboprophylaxis in patients newly diagnosed with multiple myeloma.

    PubMed

    Chalayer, Emilie; Bourmaud, Aurélie; Tinquaut, Fabien; Chauvin, Franck; Tardy, Bernard

    2016-09-01

    The aim of this study was to assess the cost-effectiveness of low molecular weight heparin versus aspirin as primary thromboprophylaxis throughout chemotherapy for newly diagnosed multiple myeloma patients treated with protocols including thalidomide from the perspective of French health care providers. We used a modeling approach combining data from the only randomized trial evaluating the efficacy of the two treatments and secondary sources for costs, and utility values. We performed a decision-tree analysis and our base case was a hypothetical cohort of 10,000 patients. A bootstrap resampling technique was used. The incremental cost-effectiveness ratio was calculated using estimated quality-adjusted life years as the efficacy outcome. Incremental costs and effectiveness were estimated for each strategy and the incremental cost-effectiveness ratio was calculated. One-way sensitivity analyses were performed. The number of quality-adjusted life years was estimated to be 0.300 with aspirin and 0.299 with heparin. The estimated gain with aspirin was therefore approximately one day. Over 6months, the mean total cost was € 1518 (SD=601) per patient in the heparin arm and € 273 (SD=1019) in the aspirin arm. This resulted in an incremental cost of € 1245 per patient treated with heparin. The incremental cost-effectiveness ratio for the aspirin versus heparin strategy was calculated to be - 687,398 € (95% CI, -13,457,369 to -225,385). Aspirin rather than heparin thromboprophylaxis, during the first six months of chemotherapy for myeloma, is associated with significant cost savings per patient and also with an unexpected slight increase in quality of life. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Fast Fourier Transform Spectral Analysis Program

    NASA Technical Reports Server (NTRS)

    Daniel, J. A., Jr.; Graves, M. L.; Hovey, N. M.

    1969-01-01

    Fast Fourier Transform Spectral Analysis Program is used in frequency spectrum analysis of postflight, space vehicle telemetered trajectory data. This computer program with a digital algorithm can calculate power spectrum rms amplitudes and cross spectrum of sampled parameters at even time increments.

  1. A comparative analysis of primary and secondary Gleason pattern predictive ability for positive surgical margins after radical prostatectomy.

    PubMed

    Sfoungaristos, S; Kavouras, A; Kanatas, P; Polimeros, N; Perimenis, P

    2011-01-01

    To compare the predictive ability of primary and secondary Gleason pattern for positive surgical margins in patients with clinically localized prostate cancer and a preoperative Gleason score ≤ 6. A retrospective analysis of the medical records of patients undergone a radical prostatectomy between January 2005 and October 2010 was conducted. Patients' age, prostate volume, preoperative PSA, biopsy Gleason score, the 1st and 2nd Gleason pattern were entered a univariate and multivariate analysis. The 1st and 2nd pattern were tested for their ability to predict positive surgical margins using receiver operating characteristic curves. Positive surgical margins were noticed in 56 cases (38.1%) out of 147 studied patients. The 2nd pattern was significantly greater in those with positive surgical margins while the 1st pattern was not significantly different between the 2 groups of patients. ROC analysis revealed that area under the curve was 0.53 (p=0.538) for the 1st pattern and 0.60 (p=0.048) for the 2nd pattern. Concerning the cases with PSA <10 ng/ml, it was also found that only the 2nd pattern had a predictive ability (p=0.050). When multiple logistic regression analysis was conducted it was found that the 2nd pattern was the only independent predictor. The second Gleason pattern was found to be of higher value than the 1st one for the prediction of positive surgical margins in patients with preoperative Gleason score ≤ 6 and this should be considered especially when a neurovascular bundle sparing radical prostatectomy is planned, in order not to harm the oncological outcome.

  2. GIS-based multicriteria overlay analysis in soil-suitability evaluation for cotton (Gossypium spp.): A case study in the black soil region of Central India

    NASA Astrophysics Data System (ADS)

    Walke, N.; Obi Reddy, G. P.; Maji, A. K.; Thayalan, S.

    2012-04-01

    In this study an attempt was made to characterize the soils of the Ringanbodi watershed, Nagpur district, Maharashtra, Central India, for soil-suitability evaluation for cotton using geographic information system (GIS)-based multicriteria overlay analysis techniques. The study shows that 8 soil series and 16 soil series associations in the study area and soils were classified into three orders, i.e., Entisol, Inceptisol, and Vertisol. The analysis reveals that the soil associations E-F, F-G, G-H, and H-G are "moderately suitable" (S2), D-E are "marginally to moderately suitable," and C-D are marginally (S3) suitable. However, soils B-C are "not suitable" to "marginally suitable" (N2-S3) and A-B are "unsuitable" (N2) for cultivation of cotton. The area analysis shows that for a cotton crop an area about 966.7 ha (49.1%) of TGA is moderately suitable and classified as S2. An area about 469.9 ha (23.8%) of TGA is marginal to moderately suitable (S3-S2). The marginally suitable soils for cotton are classified as S3 and cover an area about 35.2 ha (1.8%) of TGA. However, a 172.3 ha (8.7%) area is not suitable (N2) to marginally suitable (S3) and a 326.9 (16.6%) area is not suitable (N2) for cotton because of uncorrectable factors like soil depth, slope, etc. The study demonstrated that GIS-based multicriteria overlay analysis of soil thematic parameters will be of immense help in soil-suitability evaluation for cotton.

  3. Effect of comprehensive cardiac telerehabilitation on one-year cardiovascular rehospitalization rate, medical costs and quality of life: A cost-effectiveness analysis.

    PubMed

    Frederix, Ines; Hansen, Dominique; Coninx, Karin; Vandervoort, Pieter; Vandijck, Dominique; Hens, Niel; Van Craenenbroeck, Emeline; Van Driessche, Niels; Dendale, Paul

    2016-05-01

    Notwithstanding the cardiovascular disease epidemic, current budgetary constraints do not allow for budget expansion of conventional cardiac rehabilitation programmes. Consequently, there is an increasing need for cost-effectiveness studies of alternative strategies such as telerehabilitation. The present study evaluated the cost-effectiveness of a comprehensive cardiac telerehabilitation programme. This multi-centre randomized controlled trial comprised 140 cardiac rehabilitation patients, randomized (1:1) to a 24-week telerehabilitation programme in addition to conventional cardiac rehabilitation (intervention group) or to conventional cardiac rehabilitation alone (control group). The incremental cost-effectiveness ratio was calculated based on intervention and health care costs (incremental cost), and the differential incremental quality adjusted life years (QALYs) gained. The total average cost per patient was significantly lower in the intervention group (€2156 ± €126) than in the control group (€2720 ± €276) (p = 0.01) with an overall incremental cost of €-564.40. Dividing this incremental cost by the baseline adjusted differential incremental QALYs (0.026 QALYs) yielded an incremental cost-effectiveness ratio of €-21,707/QALY. The number of days lost due to cardiovascular rehospitalizations in the intervention group (0.33 ± 0.15) was significantly lower than in the control group (0.79 ± 0.20) (p = 0.037). This paper shows the addition of cardiac telerehabilitation to conventional centre-based cardiac rehabilitation to be more effective and efficient than centre-based cardiac rehabilitation alone. These results are useful for policy makers charged with deciding how limited health care resources should best be allocated in the era of exploding need. © The European Society of Cardiology 2015.

  4. Comparison of Multifrequency Bioelectrical Impedance vs. Dual-Energy X-ray Absorptiometry for Assessing Body Composition Changes After Participation in a 10-Week Resistance Training Program.

    PubMed

    Schoenfeld, Brad J; Nickerson, Brett S; Wilborn, Colin D; Urbina, Stacie L; Hayward, Sara B; Krieger, James; Aragon, Alan A; Tinsley, Grant M

    2018-06-20

    Schoenfeld, BJ, Nickerson, BS, Wilborn, CD, Urbina, SL, Hayward, SB, Krieger, J, Aragon, AA, and Tinsley, G. Comparison of multifrequency bioelectrical impedance vs. dual-energy x-ray absorptiometry for assessing body composition changes after participation in a 10-week resistance training program. J Strength Cond Res XX(X): 000-000, 2018-The purpose of this study was to assess the ability of multifrequency bioelectrical impedance analysis (MF-BIA) to determine alterations in total and segmental body composition across a 10-week resistance training (RT) program in comparison with the criterion reference dual-energy X-ray absorptiometry (DXA). Twenty-one young male volunteers (mean ± SD; age = 22.9 ± 3.0 years; height = 175.5 ± 5.9 cm; body mass = 82.9 ± 13.6 kg; body mass index = 26.9 ± 3.6) performed an RT program that included exercises for all major muscle groups. Body composition was assessed using both methods before and after the intervention; change scores were determined by subtracting pre-test values from post-test values for percent body fat ([INCREMENT]%BF), fat mass ([INCREMENT]FM), and fat-free mass ([INCREMENT]FFM). Mean changes were not significantly different when comparing MF-BIA with DXA for [INCREMENT]%BF (-1.05 vs. -1.28%), [INCREMENT]FM (-1.13 vs. -1.19 kg), and FFM (0.10 vs. 0.37 kg, respectively). Both methods showed strong agreement for [INCREMENT]%BF (r = 0.75; standard error of the estimate [SEE] = 1.15%), [INCREMENT]FM (r = 0.84; SEE 1.0 kg), and [INCREMENT]FFM (r = 0.71; SEE of 1.5 kg). The 2 methods were poor predictors of each other in regards to changes in segmental measurements. Our data indicate that MF-BIA is an acceptable alternative for tracking changes in FM and FFM during a combined diet and exercise program in young, athletic men, but segmental lean mass measurements must be interpreted with circumspection.

  5. Cervical and Incisal Marginal Discrepancy in Ceramic Laminate Veneering Materials: A SEM Analysis

    PubMed Central

    Ranganathan, Hemalatha; Ganapathy, Dhanraj M.; Jain, Ashish R.

    2017-01-01

    Context: Marginal discrepancy influenced by the choice of processing material used for the ceramic laminate veneers needs to be explored further for better clinical application. Aims: This study aimed to evaluate the amount of cervical and incisal marginal discrepancy associated with different ceramic laminate veneering materials. Settings and Design: This was an experimental, single-blinded, in vitro trial. Subjects and Methods: Ten central incisors were prepared for laminate veneers with 2 mm uniform reduction and heavy chamfer finish line. Ceramic laminate veneers fabricated over the prepared teeth using four different processing materials were categorized into four groups as Group I - aluminous porcelain veneers, Group II - lithium disilicate ceramic veneers, Group III - lithium disilicate-leucite-based veneers, Group IV - zirconia-based ceramic veneers. The cervical and incisal marginal discrepancy was measured using a scanning electron microscope. Statistical Analysis Used: ANOVA and post hoc Tukey honest significant difference (HSD) tests were used for statistical analysis. Results: The cervical and incisal marginal discrepancy for four groups was Group I - 114.6 ± 4.3 μm, 132.5 ± 6.5 μm, Group II - 86.1 ± 6.3 μm, 105.4 ± 5.3 μm, Group III - 71.4 ± 4.4 μm, 91.3 ± 4.7 μm, and Group IV - 123.1 ± 4.1 μm, 142.0 ± 5.4 μm. ANOVA and post hoc Tukey HSD tests observed a statistically significant difference between the four test specimens with regard to cervical marginal discrepancy. The cervical and incisal marginal discrepancy scored F = 243.408, P < 0.001 and F = 180.844, P < 0.001, respectively. Conclusion: This study concluded veneers fabricated using leucite reinforced lithium disilicate exhibited the least marginal discrepancy followed by lithium disilicate ceramic, aluminous porcelain, and zirconia-based ceramics. The marginal discrepancy was more in the incisal region than in the cervical region in all the groups. PMID:28839415

  6. Economic analysis of basiliximab in renal transplantation.

    PubMed

    Keown, P A; Balshaw, R; Krueger, H; Baladi, J F

    2001-06-15

    Basiliximab is a chimeric monoclonal directed against the alpha-chain of the interleukin-2 receptor. International studies have shown that it is highly effective in preventing acute rejection in patients receiving Neoral, and causes no measurable incremental toxicity, but its economic value remains unknown. This study employed an economic model to examine the potential economic benefit of basiliximab. Parameter estimates were derived from a randomized, prospective, double-blind study conducted in 21 renal transplant centers in seven countries in which 380 adult primary allograft recipients were randomized within center to receive basiliximab (20 mg i.v.) on days 0 and 4 or placebo in addition to dual immunosuppression with Neoral and steroids. Key clinical events included primary hospitalization, immunosuppressive drug use, patient and graft survival, graft rejection, treatment of rejection, dialysis, and repeat hospitalization. Health resources were valued via a comprehensive electronic cost dictionary, based upon a detailed economic evaluation of renal transplantation in Canada. Medication costs were calculated from hospital pharmacy acquisition costs; basiliximab was assessed a zero cost. The average estimated cost per patient for the first year after transplant was $55,393 (Canadian dollars) for placebo and $50,839 for basiliximab, rising to $141,690 and $130,592, respectively, after 5 years. A principal component of the cost in both groups was accrued during the initial transplant hospitalization ($14,663 for standard therapy and $14,099 for basiliximab). An additional $15,852 and $14,130 was attributable to continued care, graft loss, and dialysis in the two groups, whereas follow-up hospitalization consumed an additional $15,538 for placebo and $13,916 for basiliximab. The mean incremental cost of dialysis was $5,397 for placebo compared with $3,821 for basiliximab, whereas incremental costs of graft loss were $2,548 compared with $2,295 in the two treatment groups. The principal costs associated with repeat admission to the transplant ward and the general ward were marginally higher for placebo ($7,395 vs. $6,300 and $5,986 vs. $4,625). Treatment of acute rejection and maintenance immunosuppressive drug use were associated with only limited savings as a result of basiliximab (savings <$200 each). Sensitivity analysis indicated that the most influential parameters affecting the savings as a result of using basiliximab were a reduction in the duration of initial and repeat hospitalization followed by the reduced risks of acute rejection and graft loss. Before accounting for the cost of the therapy itself, basiliximab produces an estimated economic saving of $4,554 during the first year after transplant, of which $3,344 is attributable to the reduced costs of graft dysfunction, including graft loss and dialysis ($1,722) and follow-up hospitalizations ($1,622). When marketed, basiliximab is expected to cost approximately $3,000 per course (two doses of 20 mg), resulting in a net first-year saving of $1,554. Under these circumstances, basiliximab can be considered a dominant therapy in renal transplantation.

  7. Do other-reports of counterproductive work behavior provide an incremental contribution over self-reports? A meta-analytic comparison.

    PubMed

    Berry, Christopher M; Carpenter, Nichelle C; Barratt, Clare L

    2012-05-01

    Much of the recent research on counterproductive work behaviors (CWBs) has used multi-item self-report measures of CWB. Because of concerns over self-report measurement, there have been recent calls to collect ratings of employees' CWB from their supervisors or coworkers (i.e., other-raters) as alternatives or supplements to self-ratings. However, little is still known about the degree to which other-ratings of CWB capture unique and valid incremental variance beyond self-report CWB. The present meta-analysis investigates a number of key issues regarding the incremental contribution of other-reports of CWB. First, self- and other-ratings of CWB were moderately to strongly correlated with each other. Second, with some notable exceptions, self- and other-report CWB exhibited very similar patterns and magnitudes of relationships with a set of common correlates. Third, self-raters reported engaging in more CWB than other-raters reported them engaging in, suggesting other-ratings capture a narrower subset of CWBs. Fourth, other-report CWB generally accounted for little incremental variance in the common correlates beyond self-report CWB. Although many have viewed self-reports of CWB with skepticism, the results of this meta-analysis support their use in most CWB research as a viable alternative to other-reports. (PsycINFO Database Record (c) 2012 APA, all rights reserved).

  8. Combining Accuracy and Efficiency: An Incremental Focal-Point Method Based on Pair Natural Orbitals.

    PubMed

    Fiedler, Benjamin; Schmitz, Gunnar; Hättig, Christof; Friedrich, Joachim

    2017-12-12

    In this work, we present a new pair natural orbitals (PNO)-based incremental scheme to calculate CCSD(T) and CCSD(T0) reaction, interaction, and binding energies. We perform an extensive analysis, which shows small incremental errors similar to previous non-PNO calculations. Furthermore, slight PNO errors are obtained by using T PNO = T TNO with appropriate values of 10 -7 to 10 -8 for reactions and 10 -8 for interaction or binding energies. The combination with the efficient MP2 focal-point approach yields chemical accuracy relative to the complete basis-set (CBS) limit. In this method, small basis sets (cc-pVDZ, def2-TZVP) for the CCSD(T) part are sufficient in case of reactions or interactions, while some larger ones (e.g., (aug)-cc-pVTZ) are necessary for molecular clusters. For these larger basis sets, we show the very high efficiency of our scheme. We obtain not only tremendous decreases of the wall times (i.e., factors >10 2 ) due to the parallelization of the increment calculations as well as of the total times due to the application of PNOs (i.e., compared to the normal incremental scheme) but also smaller total times with respect to the standard PNO method. That way, our new method features a perfect applicability by combining an excellent accuracy with a very high efficiency as well as the accessibility to larger systems due to the separation of the full computation into several small increments.

  9. Incremental Costs and Cost Effectiveness of Intensive Treatment in Individuals with Type 2 Diabetes Detected by Screening in the ADDITION-UK Trial: An Update with Empirical Trial-Based Cost Data.

    PubMed

    Laxy, Michael; Wilson, Edward C F; Boothby, Clare E; Griffin, Simon J

    2017-12-01

    There is uncertainty about the cost effectiveness of early intensive treatment versus routine care in individuals with type 2 diabetes detected by screening. To derive a trial-informed estimate of the incremental costs of intensive treatment as delivered in the Anglo-Danish-Dutch Study of Intensive Treatment in People with Screen-Detected Diabetes in Primary Care-Europe (ADDITION) trial and to revisit the long-term cost-effectiveness analysis from the perspective of the UK National Health Service. We analyzed the electronic primary care records of a subsample of the ADDITION-Cambridge trial cohort (n = 173). Unit costs of used primary care services were taken from the published literature. Incremental annual costs of intensive treatment versus routine care in years 1 to 5 after diagnosis were calculated using multilevel generalized linear models. We revisited the long-term cost-utility analyses for the ADDITION-UK trial cohort and reported results for ADDITION-Cambridge using the UK Prospective Diabetes Study Outcomes Model and the trial-informed cost estimates according to a previously developed evaluation framework. Incremental annual costs of intensive treatment over years 1 to 5 averaged £29.10 (standard error = £33.00) for consultations with general practitioners and nurses and £54.60 (standard error = £28.50) for metabolic and cardioprotective medication. For ADDITION-UK, over the 10-, 20-, and 30-year time horizon, adjusted incremental quality-adjusted life-years (QALYs) were 0.014, 0.043, and 0.048, and adjusted incremental costs were £1,021, £1,217, and £1,311, resulting in incremental cost-effectiveness ratios of £71,232/QALY, £28,444/QALY, and £27,549/QALY, respectively. Respective incremental cost-effectiveness ratios for ADDITION-Cambridge were slightly higher. The incremental costs of intensive treatment as delivered in the ADDITION-Cambridge trial were lower than expected. Given UK willingness-to-pay thresholds in patients with screen-detected diabetes, intensive treatment is of borderline cost effectiveness over a time horizon of 20 years and more. Copyright © 2017. Published by Elsevier Inc.

  10. 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 surgical margin rate among three surgical approaches. The bladder neck was the most common location of positive surgical margin in robot-assisted radical prostatectomy and apex in open radical prostatectomy and laparoscopic radical prostatectomy. Although robot-assisted radical prostatectomy may contribute to the reduction of positive surgical margin, dissection of the bladder neck requires careful attention to avoid positive surgical margins.

  11. Analysis of Tube Free Hydroforming using an Inverse Approach with FLD-based Adjustment of Process Parameters

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

    Nguyen, Ba Nghiep; Johnson, Kenneth I.; Khaleel, Mohammad A.

    2003-04-01

    This paper employs an inverse approach (IA) formulation for the analysis of tubes under free hydroforming conditions. The IA formulation is derived from that of Guo et al. established for flat sheet hydroforming analysis using constant strain triangular membrane elements. At first, an incremental analysis of free hydroforming for a hot-dip galvanized (HG/Z140) DP600 tube is performed using the finite element Marc code. The deformed geometry obtained at the last converged increment is then used as the final configuration in the inverse analysis. This comparative study allows us to assess the predicting capability of the inverse analysis. The results willmore » be compared with the experimental values determined by Asnafi and Skogsgardh. After that, a procedure based on a forming limit diagram (FLD) is proposed to adjust the process parameters such as the axial feed and internal pressure. Finally, the adjustment process is illustrated through a re-analysis of the same tube using the inverse approach« less

  12. 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.

  13. Influence of Manufacturing Methods of Implant-Supported Crowns on External and Internal Marginal Fit: A Micro-CT Analysis.

    PubMed

    Moris, Izabela C M; Monteiro, Silas Borges; Martins, Raíssa; Ribeiro, Ricardo Faria; Gomes, Erica A

    2018-01-01

    To evaluate the influence of different manufacturing methods of single implant-supported metallic crowns on the internal and external marginal fit through computed microtomography. Forty external hexagon implants were divided into 4 groups ( n = 8), according to the manufacturing method: GC, conventional casting; GI, induction casting; GP, plasma casting; and GCAD, CAD/CAM machining. The crowns were attached to the implants with insertion torque of 30 N·cm. The external (vertical and horizontal) marginal fit and internal fit were assessed through computed microtomography. Internal and external marginal fit data ( μ m) were submitted to a one-way ANOVA and Tukey's test ( α = .05). Qualitative evaluation of the images was conducted by using micro-CT. The statistical analysis revealed no significant difference between the groups for vertical misfit ( P = 0.721). There was no significant difference ( P > 0.05) for the internal and horizontal marginal misfit in the groups GC, GI, and GP, but it was found for the group GCAD ( P ≤ 0.05). Qualitative analysis revealed that most of the samples of cast groups exhibited crowns underextension while the group GCAD showed overextension. The manufacturing method of the crowns influenced the accuracy of marginal fit between the prosthesis and implant. The best results were found for the crowns fabricated through CAD/CAM machining.

  14. Excess Capacity in China’s Power Systems: A Regional Analysis

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

    Lin, Jiang; Liu, Xu; Karl, Fredrich

    2016-11-01

    This paper examines China’s regional electricity grids using a reliability perspective, which is commonly measured in terms of a reserve margin. Our analysis shows that at the end of 2014, the average reserve margin for China as a whole was roughly 28%, almost twice as high as a typical planning reserve margin in the U.S. However, this national average masks huge variations in reserve margins across major regional power grid areas: the northeastern region has the highest reserve margin of over 60%, followed by the northwestern region at 49%, and the southern grid area at 35%. In this analysis, wemore » also examined future reserve margins for regional electricity grids in China under two scenarios: 1) a low scenario of national annual electricity consumption growth rates of 1.5% between 2015 and 2020 and 1.0% between 2020 and 2025, and 2) a high scenario of annual average growth rates of 3.0% and 2.0%, respectively. Both scenarios suggest that the northeastern, northwestern, and southern regions have significant excess generation capacity, and that this excess capacity situation will continue over the next decade without regulatory intervention. The northern and central regions could have sufficient generation capacity to 2020, but may require additional resources in a higher growth scenario. The eastern region requires new resources by 2020 in both scenarios.« less

  15. Complex Physiological Response of Norway Spruce to Atmospheric Pollution - Decreased Carbon Isotope Discrimination and Unchanged Tree Biomass Increment.

    PubMed

    Čada, Vojtěch; Šantrůčková, Hana; Šantrůček, Jiří; Kubištová, Lenka; Seedre, Meelis; Svoboda, Miroslav

    2016-01-01

    Atmospheric pollution critically affects forest ecosystems around the world by directly impacting the assimilation apparatus of trees and indirectly by altering soil conditions, which subsequently also leads to changes in carbon cycling. To evaluate the extent of the physiological effect of moderate level sulfate and reactive nitrogen acidic deposition, we performed a retrospective dendrochronological analysis of several physiological parameters derived from periodic measurements of carbon stable isotope composition ((13)C discrimination, intercellular CO2 concentration and intrinsic water use efficiency) and annual diameter increments (tree biomass increment, its inter-annual variability and correlation with temperature, cloud cover, precipitation and Palmer drought severity index). The analysis was performed in two mountain Norway spruce (Picea abies) stands of the Bohemian Forest (Czech Republic, central Europe), where moderate levels of pollution peaked in the 1970s and 1980s and no evident impact on tree growth or link to mortality has been reported. The significant influence of pollution on trees was expressed most sensitively by a 1.88‰ reduction of carbon isotope discrimination (Δ(13)C). The effects of atmospheric pollution interacted with increasing atmospheric CO2 concentration and temperature. As a result, we observed no change in intercellular CO2 concentrations (Ci), an abrupt increase in water use efficiency (iWUE) and no change in biomass increment, which could also partly result from changes in carbon partitioning (e.g., from below- to above-ground). The biomass increment was significantly related to Δ(13)C on an individual tree level, but the relationship was lost during the pollution period. We suggest that this was caused by a shift from the dominant influence of the photosynthetic rate to stomatal conductance on Δ(13)C during the pollution period. Using biomass increment-climate correlation analyses, we did not identify any clear pollution-related change in water stress or photosynthetic limitation (since biomass increment did not become more sensitive to drought/precipitation or temperature/cloud cover, respectively). Therefore, we conclude that the direct effect of moderate pollution on stomatal conductance was likely the main driver of the observed physiological changes. This mechanism probably caused weakening of the spruce trees and increased sensitivity to other stressors.

  16. Complex Physiological Response of Norway Spruce to Atmospheric Pollution – Decreased Carbon Isotope Discrimination and Unchanged Tree Biomass Increment

    PubMed Central

    Čada, Vojtěch; Šantrůčková, Hana; Šantrůček, Jiří; Kubištová, Lenka; Seedre, Meelis; Svoboda, Miroslav

    2016-01-01

    Atmospheric pollution critically affects forest ecosystems around the world by directly impacting the assimilation apparatus of trees and indirectly by altering soil conditions, which subsequently also leads to changes in carbon cycling. To evaluate the extent of the physiological effect of moderate level sulfate and reactive nitrogen acidic deposition, we performed a retrospective dendrochronological analysis of several physiological parameters derived from periodic measurements of carbon stable isotope composition (13C discrimination, intercellular CO2 concentration and intrinsic water use efficiency) and annual diameter increments (tree biomass increment, its inter-annual variability and correlation with temperature, cloud cover, precipitation and Palmer drought severity index). The analysis was performed in two mountain Norway spruce (Picea abies) stands of the Bohemian Forest (Czech Republic, central Europe), where moderate levels of pollution peaked in the 1970s and 1980s and no evident impact on tree growth or link to mortality has been reported. The significant influence of pollution on trees was expressed most sensitively by a 1.88‰ reduction of carbon isotope discrimination (Δ13C). The effects of atmospheric pollution interacted with increasing atmospheric CO2 concentration and temperature. As a result, we observed no change in intercellular CO2 concentrations (Ci), an abrupt increase in water use efficiency (iWUE) and no change in biomass increment, which could also partly result from changes in carbon partitioning (e.g., from below- to above-ground). The biomass increment was significantly related to Δ13C on an individual tree level, but the relationship was lost during the pollution period. We suggest that this was caused by a shift from the dominant influence of the photosynthetic rate to stomatal conductance on Δ13C during the pollution period. Using biomass increment-climate correlation analyses, we did not identify any clear pollution-related change in water stress or photosynthetic limitation (since biomass increment did not become more sensitive to drought/precipitation or temperature/cloud cover, respectively). Therefore, we conclude that the direct effect of moderate pollution on stomatal conductance was likely the main driver of the observed physiological changes. This mechanism probably caused weakening of the spruce trees and increased sensitivity to other stressors. PMID:27375659

  17. Relating annual increments of the endangered Blanding's turtle plastron growth to climate

    PubMed Central

    Richard, Monik G; Laroque, Colin P; Herman, Thomas B

    2014-01-01

    This research is the first published study to report a relationship between climate variables and plastron growth increments of turtles, in this case the endangered Nova Scotia Blanding's turtle (Emydoidea blandingii). We used techniques and software common to the discipline of dendrochronology to successfully cross-date our growth increment data series, to detrend and average our series of 80 immature Blanding's turtles into one common chronology, and to seek correlations between the chronology and environmental temperature and precipitation variables. Our cross-dated chronology had a series intercorrelation of 0.441 (above 99% confidence interval), an average mean sensitivity of 0.293, and an average unfiltered autocorrelation of 0.377. Our master chronology represented increments from 1975 to 2007 (33 years), with index values ranging from a low of 0.688 in 2006 to a high of 1.303 in 1977. Univariate climate response function analysis on mean monthly air temperature and precipitation values revealed a positive correlation with the previous year's May temperature and current year's August temperature; a negative correlation with the previous year's October temperature; and no significant correlation with precipitation. These techniques for determining growth increment response to environmental variables should be applicable to other turtle species and merit further exploration. PMID:24963390

  18. Relating annual increments of the endangered Blanding's turtle plastron growth to climate.

    PubMed

    Richard, Monik G; Laroque, Colin P; Herman, Thomas B

    2014-05-01

    This research is the first published study to report a relationship between climate variables and plastron growth increments of turtles, in this case the endangered Nova Scotia Blanding's turtle (Emydoidea blandingii). We used techniques and software common to the discipline of dendrochronology to successfully cross-date our growth increment data series, to detrend and average our series of 80 immature Blanding's turtles into one common chronology, and to seek correlations between the chronology and environmental temperature and precipitation variables. Our cross-dated chronology had a series intercorrelation of 0.441 (above 99% confidence interval), an average mean sensitivity of 0.293, and an average unfiltered autocorrelation of 0.377. Our master chronology represented increments from 1975 to 2007 (33 years), with index values ranging from a low of 0.688 in 2006 to a high of 1.303 in 1977. Univariate climate response function analysis on mean monthly air temperature and precipitation values revealed a positive correlation with the previous year's May temperature and current year's August temperature; a negative correlation with the previous year's October temperature; and no significant correlation with precipitation. These techniques for determining growth increment response to environmental variables should be applicable to other turtle species and merit further exploration.

  19. 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.

  20. A study of the mutational landscape of pediatric-type follicular lymphoma and pediatric nodal marginal zone lymphoma.

    PubMed

    Ozawa, Michael G; Bhaduri, Aparna; Chisholm, Karen M; Baker, Steven A; Ma, Lisa; Zehnder, James L; Luna-Fineman, Sandra; Link, Michael P; Merker, Jason D; Arber, Daniel A; Ohgami, Robert S

    2016-10-01

    Pediatric-type follicular lymphoma and pediatric marginal zone lymphoma are two of the rarest B-cell lymphomas. These lymphomas occur predominantly in the pediatric population and show features distinct from their more common counterparts in adults: adult-type follicular lymphoma and adult-type nodal marginal zone lymphoma. Here we report a detailed whole-exome deep sequencing analysis of a cohort of pediatric-type follicular lymphomas and pediatric marginal zone lymphomas. This analysis revealed a recurrent somatic variant encoding p.Lys66Arg in the transcription factor interferon regulatory factor 8 (IRF8) in 3 of 6 cases (50%) of pediatric-type follicular lymphoma. This specific point mutation was not detected in pediatric marginal zone lymphoma or in adult-type follicular lymphoma. Additional somatic point mutations in pediatric-type follicular lymphoma were observed in genes involved in transcription, intracellular signaling, and cell proliferation. In pediatric marginal zone lymphoma, no recurrent mutation was identified; however, somatic point mutations were observed in genes involved in cellular adhesion, cytokine regulatory elements, and cellular proliferation. A somatic variant in AMOTL1, a recurrently mutated gene in splenic marginal zone lymphoma, was also identified in a case of pediatric marginal zone lymphoma. The overall non-synonymous mutational burden was low in both pediatric-type follicular lymphoma and pediatric marginal zone lymphoma (4.6 mutations per exome). Altogether, these findings support a distinctive genetic basis for pediatric-type follicular lymphoma and pediatric marginal zone lymphoma when compared with adult subtypes and to one another. Moreover, identification of a recurrent point mutation in IRF8 provides insight into a potential driver mutation in the pathogenesis of pediatric-type follicular lymphoma with implications for novel diagnostic or therapeutic strategies.

  1. A study of the mutational landscape of pediatric-type follicular lymphoma and pediatric nodal marginal zone lymphoma

    PubMed Central

    Ozawa, Michael G; Bhaduri, Aparna; Chisholm, Karen M; Baker, Steven A; Ma, Lisa; Zehnder, James L; Luna-Fineman, Sandra; Link, Michael P; Merker, Jason D; Arber, Daniel A; Ohgami, Robert S

    2016-01-01

    Pediatric-type follicular lymphoma and pediatric marginal zone lymphoma are two of the rarest B-cell lymphomas. These lymphomas occur predominantly in the pediatric population and show features distinct from their more common counterparts in adults: adult-type follicular lymphoma and adult-type nodal marginal zone lymphoma. Here we report a detailed whole-exome deep sequencing analysis of a cohort of pediatric-type follicular lymphomas and pediatric marginal zone lymphomas. This analysis revealed a recurrent somatic variant encoding p.Lys66Arg in the transcription factor interferon regulatory factor 8 (IRF8) in 3 of 6 cases (50%) of pediatric-type follicular lymphoma. This specific point mutation was not detected in pediatric marginal zone lymphoma or in adult-type follicular lymphoma. Additional somatic point mutations in pediatric-type follicular lymphoma were observed in genes involved in transcription, intracellular signaling, and cell proliferation. In pediatric marginal zone lymphoma, no recurrent mutation was identified; however, somatic point mutations were observed in genes involved in cellular adhesion, cytokine regulatory elements, and cellular proliferation. A somatic variant in AMOTL1, a recurrently mutated gene in splenic marginal zone lymphoma, was also identified in a case of pediatric marginal zone lymphoma. The overall non-synonymous mutational burden was low in both pediatric-type follicular lymphoma and pediatric marginal zone lymphoma (4.6 mutations per exome). Altogether, these findings support a distinctive genetic basis for pediatric-type follicular lymphoma and pediatric marginal zone lymphoma when compared with adult subtypes and to one another. Moreover, identification of a recurrent point mutation in IRF8 provides insight into a potential driver mutation in the pathogenesis of pediatric-type follicular lymphoma with implications for novel diagnostic or therapeutic strategies. PMID:27338637

  2. Marginal and Random Intercepts Models for Longitudinal Binary Data with Examples from Criminology

    ERIC Educational Resources Information Center

    Long, Jeffrey D.; Loeber, Rolf; Farrington, David P.

    2009-01-01

    Two models for the analysis of longitudinal binary data are discussed: the marginal model and the random intercepts model. In contrast to the linear mixed model (LMM), the two models for binary data are not subsumed under a single hierarchical model. The marginal model provides group-level information whereas the random intercepts model provides…

  3. Marginal lands for biocontrol and ecosystem services: Where to enhance and what do we put there?

    USDA-ARS?s Scientific Manuscript database

    Analysis of the Coastal Plain of Georgia, USA identified over 300,000 hectares of marginal land. There is a potential to grow other non-commodity native plants in marginal areas that have the potential to improve the diversity of the landscape and promote ecosystem services. Bioenergy feedstocks are...

  4. 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…

  5. Cost-Value Analysis and the SAVE: A Work in Progress, But an Option for Localised Decision Making?

    PubMed

    Karnon, Jonathan; Partington, Andrew

    2015-12-01

    Cost-value analysis aims to address the limitations of the quality-adjusted life-year (QALY) by incorporating the strength of public concerns for fairness in the allocation of scarce health care resources. To date, the measurement of value has focused on equity weights to reflect societal preferences for the allocation of QALY gains. Another approach is to use a non-QALY-based measure of value, such as an outcome 'equivalent to saving the life of a young person' (a SAVE). This paper assesses the feasibility and validity of using the SAVE as a measure of value for the economic evaluation of health care technologies. A web-based person trade-off (PTO) survey was designed and implemented to estimate equivalent SAVEs for outcome events associated with the progression and treatment of early-stage breast cancer. The estimated equivalent SAVEs were applied to the outputs of an existing decision analytic model for early breast cancer. The web-based PTO survey was undertaken by 1094 respondents. Validation tests showed that 68 % of eligible responses revealed consistent ordering of responses and 32 % displayed ordinal transitivity, while 37 % of respondents showing consistency and ordinal transitivity approached cardinal transitivity. Using consistent and ordinally transitive responses, the mean incremental cost per SAVE gained was £ 3.72 million. Further research is required to improve the validity of the SAVE, which may include a simpler web-based survey format or a face-to-face format to facilitate more informed responses. A validated method for estimating equivalent SAVEs is unlikely to replace the QALY as the globally preferred measure of outcome, but the SAVE may provide a useful alternative for localized decision makers with relatively small, constrained budgets-for example, in programme budgeting and marginal analysis.

  6. Cost-Effectiveness Analysis of the Self-Management Program for Thai Patients with Metabolic Syndrome.

    PubMed

    Sakulsupsiri, Anut; Sakthong, Phantipa; Winit-Watjana, Win

    2016-05-01

    Lifestyle modification programs are partly evaluated for their usefulness. This study aimed to assess the cost-effectiveness and healthy lifestyle persistence of a self-management program (SMP) for patients with metabolic syndrome (MetS) in Thai health care settings. A cost-effectiveness analysis was performed on the basis of an intervention study of 90 patients with MetS randomly allocated to the SMP and control groups. A Markov model with the Difference-in-Difference method was used to predict the lifetime costs from a societal perspective and quality-adjusted life-years (QALYs), of which 95% confidence intervals (CIs) were estimated by bootstrapping. The cost-effectiveness analysis, along with healthy lifestyle persistence, was performed using the discount rate of 3% per annum. Parameter uncertainties were identified using one-way and probabilistic sensitivity analyses. The lifetime costs tended to decrease in both groups. The SMP could save lifetime costs (-2310 baht; 95% CI -5960 to 1400) and gain QALYs (0.0098; 95% CI -0.0003 to 0.0190), compared with ordinary care. The probability of cost-effectiveness was 99.4% from the Monte-Carlo simulation, and the program was deemed cost-effective at dropout rates below 69% per year as determined by the threshold of 160,000 baht per QALY gained. The cost of macrovascular complications was the most influencing variable for the overall incremental cost-effectiveness ratio. The SMP provided by the health care settings is marginally cost-effective, and the persistence results support the implementation of the program to minimize the complications and economic burden of patients with MetS. Copyright © 2016 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

  7. Dose-response relationship between dietary magnesium intake, serum magnesium concentration and risk of hypertension: a systematic review and meta-analysis of prospective cohort studies.

    PubMed

    Han, Hedong; Fang, Xin; Wei, Xin; Liu, Yuzhou; Jin, Zhicao; Chen, Qi; Fan, Zhongjie; Aaseth, Jan; Hiyoshi, Ayako; He, Jia; Cao, Yang

    2017-05-05

    The findings of prospective cohort studies are inconsistent regarding the association between dietary magnesium intake and serum magnesium concentration and the risk of hypertension. We aimed to review the evidence from prospective cohort studies and perform a dose-response meta-analysis to investigate the relationship between dietary magnesium intake and serum magnesium concentrations and the risk of hypertension. We searched systematically PubMed, EMBASE and the Cochrane Library databases from October 1951 through June 2016. Prospective cohort studies reporting effect estimates with 95% confidence intervals (CIs) for hypertension in more than two categories of dietary magnesium intake and/or serum magnesium concentrations were included. Random-effects models were used to combine the estimated effects. Nine articles (six on dietary magnesium intake, two on serum magnesium concentration and one on both) of ten cohort studies, including 20,119 cases of hypertension and 180,566 participates, were eligible for inclusion in the meta-analysis. We found an inverse association between dietary magnesium intake and the risk of hypertension [relative risk (RR) = 0.92; 95% CI: 0.86, 0.98] comparing the highest intake group with the lowest. A 100 mg/day increment in magnesium intake was associated with a 5% reduction in the risk of hypertension (RR = 0.95; 95% CI: 0.90, 1.00). The association of serum magnesium concentration with the risk of hypertension was marginally significant (RR = 0.91; 95% CI: 0.80, 1.02). Current evidence supports the inverse dose-response relationship between dietary magnesium intake and the risk of hypertension. However, the evidence about the relationship between serum magnesium concentration and hypertension is limited.

  8. Fish consumption and CHD mortality: an updated meta-analysis of seventeen cohort studies.

    PubMed

    Zheng, Jusheng; Huang, Tao; Yu, Yinghua; Hu, Xiaojie; Yang, Bin; Li, Duo

    2012-04-01

    Results of studies on fish consumption and CHD mortality are inconsistent. The present updated meta-analysis was conducted to investigate the up-to-date pooling effects. A random-effects model was used to pool the risk estimates. Generalized least-squares regression and restricted cubic splines were used to assess the possible dose-response relationship. Subgroup analyses were conducted to examine the sources of heterogeneity. PubMed and ISI Web of Science databases up to September 2010 were searched and secondary referencing qualified for inclusion in the study. Seventeen cohorts with 315,812 participants and average follow-up period of 15·9 years were identified. Compared with the lowest fish intake (<1 serving/month or 1-3 servings/month), the pooled relative risk (RR) of fish intake on CHD mortality was 0·84 (95% CI 0·75, 0·95) for low fish intake (1 serving/week), 0·79 (95% CI 0·67, 0·92) for moderate fish intake (2-4 servings/week) and 0·83 (95% CI 0·68, 1·01) for high fish intake (>5 servings/week). The dose-response analysis indicated that every 15 g/d increment of fish intake decreased the risk of CHD mortality by 6% (RR = 0·94; 95% CI 0·90, 0·98). The method of dietary assessment, gender and energy adjustment affected the results remarkably. Our results indicate that either low (1 serving/week) or moderate fish consumption (2-4 servings/week) has a significantly beneficial effect on the prevention of CHD mortality. High fish consumption (>5 servings/week) possesses only a marginally protective effect on CHD mortality, possibly due to the limited studies included in this group.

  9. Vasa previa screening strategies: a decision and cost-effectiveness analysis.

    PubMed

    Sinkey, R G; Odibo, A O

    2018-05-22

    The aim of this study is to perform a decision and cost-effectiveness analysis comparing four screening strategies for the antenatal diagnosis of vasa previa among singleton pregnancies. A decision-analytic model was constructed comparing vasa previa screening strategies. Published probabilities and costs were applied to four transvaginal screening scenarios which occurred at the time of mid-trimester ultrasound: no screening, ultrasound-indicated screening, screening pregnancies conceived by in vitro fertilization (IVF), and universal screening. Ultrasound-indicated screening was defined as performing a transvaginal ultrasound at the time of routine anatomy ultrasound in response to one of the following sonographic findings associated with an increased risk of vasa previa: low-lying placenta, marginal or velamentous cord insertion, or bilobed or succenturiate lobed placenta. The primary outcome was cost per quality adjusted life years (QALY) in U.S. dollars. The analysis was from a healthcare system perspective with a willingness to pay (WTP) threshold of $100,000 per QALY selected. One-way and multivariate sensitivity analyses (Monte-Carlo simulation) were performed. This decision-analytic model demonstrated that screening pregnancies conceived by IVF was the most cost-effective strategy with an incremental cost effectiveness ratio (ICER) of $29,186.50 / QALY. Ultrasound-indicated screening was the second most cost-effective with an ICER of $56,096.77 / QALY. These data were robust to all one-way and multivariate sensitivity analyses performed. Within our baseline assumptions, transvaginal ultrasound screening for vasa previa appears to be most cost-effective when performed among IVF pregnancies. However, both IVF and ultrasound-indicated screening strategies fall within contemporary willingness-to-pay thresholds, suggesting that both strategies may be appropriate to apply in clinical practice. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  10. Joint protection and hand exercises for hand osteoarthritis: an economic evaluation comparing methods for the analysis of factorial trials

    PubMed Central

    Oppong, Raymond; Nicholls, Elaine; Whitehurst, David G. T.; Hill, Susan; Hammond, Alison; Hay, Elaine M.; Dziedzic, Krysia

    2015-01-01

    Objectives. Evidence regarding the cost-effectiveness of joint protection and hand exercises for the management of hand OA is not well established. The primary aim of this study is to assess the cost-effectiveness (cost-utility) of these management options. In addition, given the absence of consensus regarding the conduct of economic evaluation alongside factorial trials, we compare different analytical methodologies. Methods. A trial-based economic evaluation to assess the cost-utility of joint protection only, hand exercises only and joint protection plus hand exercises compared with leaflet and advice was undertaken over a 12 month period from a UK National Health Service perspective. Patient-level mean costs and mean quality-adjusted life years (QALYs) were calculated for each trial arm. Incremental cost-effectiveness ratios (ICERs) were estimated and cost-effectiveness acceptability curves were constructed. The base case analysis used a within-the-table analysis methodology. Two further methods were explored: the at-the-margins approach and a regression-based approach with or without an interaction term. Results. Mean costs (QALYs) were £58.46 (s.d. 0.662) for leaflet and advice, £92.12 (s.d. 0.659) for joint protection, £64.51 (s.d. 0.681) for hand exercises and £112.38 (s.d. 0.658) for joint protection plus hand exercises. In the base case, hand exercises were the cost-effective option, with an ICER of £318 per QALY gained. Hand exercises remained the most cost-effective management strategy when adopting alternative methodological approaches. Conclusion. This is the first trial evaluating the cost-effectiveness of occupational therapy-supported approaches to self-management for hand OA. Our findings showed that hand exercises were the most cost-effective option. PMID:25339642

  11. Negative Stress Margins - Are They Real?

    NASA Technical Reports Server (NTRS)

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

    2011-01-01

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

  12. Numerical Analysis of Laminated, Orthotropic Composite Structures

    DTIC Science & Technology

    1975-11-01

    the meridian plane. In the first model , a nine degree-of-freedom, straight sided, tri- angular element was used. In this element, the three...E ■ 13.79 GPa v«. ■ «25» 6.. ■ 4.82 GPa ns its V . « .25, G. « 4.82 GPa nt nt vst * ,4S» 6st * 1*379 6P...means zero values of axial accelera- tion, and angular acceleration and velocity for each load increment) NLINC (Number of load increments with time

  13. Public Key Infrastructure (PKI) Increment 2 Root Cause Analysis (RCA) for Performance Assessments and Root Cause Analyses (PARCA)

    DTIC Science & Technology

    2015-05-01

    for issuing this critical change:  Inability to achieve PKI Increment 2 Full Deployment Decision ( FDD ) within five years of program initiation...March 1, 2014 deadline), and  Delay of over one year in the original FDD estimate provided to the Congress (1 March 2014 deadline). The proximate...to support a 1 March 2014 FDD .” The Director, Performance Assessments and Root Cause Analyses (PARCA), asked the Institute for Defense Analyses

  14. Analysis of Marine Corps Renewable Energy Planning to Meet Installation Energy Security Requirements

    DTIC Science & Technology

    2013-12-03

    experimentation eventually gives way to the era of ferment . A few new technologies break through in the industry and are applied to a growing number of niche...experimentation and ferment eventually give way to an era of incremental change, where the industry down-selects to the most successful and efficient...clearly in the later part of the era of incremental change. Most renewables, however, are only just now moving into the second phase, the era of ferment

  15. Warfighter Information Network - Tactical (WIN-T) Increment 2: Second Follow-on Operational Test and Evaluation

    DTIC Science & Technology

    2015-05-01

    HNW line-of-sight network is mounted on a 10-meter telescoping mast located just aft of the TCN’s cab. The flat plate Range Throughput Extension Kit... TAC – Tactical Command Post ATH – At-the-Halt PoP – Point of Presence SNE – Soldier Network Extension NOSC – Network Operations & Security...Survivability/Lethality Analysis Directorate (ARL/SLAD) conducted a Cooperative Vulnerability and Penetration Assessment on WIN-T Increment 2. The Army

  16. Posaconazole vs fluconazole or itraconazole for prevention of invasive fungal diseases in patients with acute myeloid leukemia or myelodysplastic syndrome: a cost-effectiveness analysis in an Asian teaching hospital.

    PubMed

    Chan, Thomas S Y; Marcella, Stephen W; Gill, Harinder; Hwang, Yu-Yan; Kwong, Yok-Lam

    2016-01-01

    Posaconazole is superior to fluconazole/itraconazole in preventing invasive fungal diseases (IFDs) in neutropenic patients. Whether the higher cost of posaconazole is offset by decreases in IFDs in a given institute requires cost-effective analysis encompassing the spectrum of IFDs and socioeconomic factors specific to that geographic area. This study performed a cost-effective analysis of posaconazole prophylaxis for IFDs in an Asian teaching hospital, employing decision modeling and data of IFDs and medication costs specific to the institute, in neutropenic patients with acute myeloid leukemia (AML) or myelodysplastic syndrome (MDS). In the cost-effectiveness analysis, the higher cost of posaconazole was partially offset by a reduction in the cost of treating IFDs that were prevented, resulting in an incremental cost of 125,954 Hong Kong dollars/16,148 USD per IFD avoided. Over a lifetime horizon, assuming same case fatality rate of IFDs in both groups, use of posaconazole results in 0.07 discounted life years saved. This corresponds to an incremental cost of 116,023 HKD/14,875 USD per life year saved. This incremental cost per life year saved in posaconazole prophylaxis fulfilled the World Health Organization defined threshold for cost-effectiveness. Posaconazole prophylaxis was cost-effective in Hong Kong.

  17. Effect of applied voltage and inter-pulse delay in spark-assisted LIBS

    NASA Astrophysics Data System (ADS)

    Robledo-Martinez, A.; Sobral, H.; Garcia-Villarreal, A.

    2018-06-01

    We report the results obtained in an investigation on the effect of the time delay between the laser and electrical pulses in a spark-assisted laser-induced breakdown spectroscopy (LIBS) experiment. The electrical discharge is produced by the discharge of a charged coaxial cable. This arrangement produces a fast unipolar current pulse (500 ns) that applies high power ( 600 kW) to the laser ablation plasma. The delay between the laser pulse and the electric pulse can be controlled at will in order to find the optimal time in terms of enhancement of the emitted lines. It was found that the application of the high voltage pulse enhances the ionic lines emitted by up to two orders of magnitude. An additional enhancement by a factor of 2-4 can be obtained delaying the application of the electric pulse by a time of 0.6-20 μs. In the tests it was noticed that the ionic lines were found to be clearly responsive to increments in the applied electric energy while the neutral lines did so marginally. Our results show that the intensification of the lines is mainly due to reheating of the ablation plasma as the application of the electrical pulse increments the temperature of the ablation plasma by about 50%. It is demonstrated that the present technique is an efficient way of intensifying the lines emitted without incurring in additional damage to the sample.

  18. Quantification of tumor fluorescence during intraoperative optical cancer imaging.

    PubMed

    Judy, Ryan P; Keating, Jane J; DeJesus, Elizabeth M; Jiang, Jack X; Okusanya, Olugbenga T; Nie, Shuming; Holt, David E; Arlauckas, Sean P; Low, Phillip S; Delikatny, E James; Singhal, Sunil

    2015-11-13

    Intraoperative optical cancer imaging is an emerging technology in which surgeons employ fluorophores to visualize tumors, identify tumor-positive margins and lymph nodes containing metastases. This study compares instrumentation to measure tumor fluorescence. Three imaging systems (Spectropen, Glomax, Flocam) measured and quantified fluorescent signal-to-background ratios (SBR) in vitro, murine xenografts, tissue phantoms and clinically. Evaluation criteria included the detection of small changes in fluorescence, sensitivity of signal detection at increasing depths and practicality of use. In vitro, spectroscopy was superior in detecting incremental differences in fluorescence than luminescence and digital imaging (Ln[SBR] = 6.8 ± 0.6, 2.4 ± 0.3, 2.6 ± 0.1, p = 0.0001). In fluorescent tumor cells, digital imaging measured higher SBRs than luminescence (6.1 ± 0.2 vs. 4.3 ± 0.4, p = 0.001). Spectroscopy was more sensitive than luminometry and digital imaging in identifying murine tumor fluorescence (SBR = 41.7 ± 11.5, 5.1 ± 1.8, 4.1 ± 0.9, p = 0.0001), and more sensitive than digital imaging at detecting fluorescence at increasing depths (SBR = 7.0 ± 3.4 vs. 2.4 ± 0.5, p = 0.03). Lastly, digital imaging was the most practical and least time-consuming. All methods detected incremental differences in fluorescence. Spectroscopy was the most sensitive for small changes in fluorescence. Digital imaging was the most practical considering its wide field of view, background noise filtering capability, and sensitivity to increasing depth.

  19. Self-supervised online metric learning with low rank constraint for scene categorization.

    PubMed

    Cong, Yang; Liu, Ji; Yuan, Junsong; Luo, Jiebo

    2013-08-01

    Conventional visual recognition systems usually train an image classifier in a bath mode with all training data provided in advance. However, in many practical applications, only a small amount of training samples are available in the beginning and many more would come sequentially during online recognition. Because the image data characteristics could change over time, it is important for the classifier to adapt to the new data incrementally. In this paper, we present an online metric learning method to address the online scene recognition problem via adaptive similarity measurement. Given a number of labeled data followed by a sequential input of unseen testing samples, the similarity metric is learned to maximize the margin of the distance among different classes of samples. By considering the low rank constraint, our online metric learning model not only can provide competitive performance compared with the state-of-the-art methods, but also guarantees convergence. A bi-linear graph is also defined to model the pair-wise similarity, and an unseen sample is labeled depending on the graph-based label propagation, while the model can also self-update using the more confident new samples. With the ability of online learning, our methodology can well handle the large-scale streaming video data with the ability of incremental self-updating. We evaluate our model to online scene categorization and experiments on various benchmark datasets and comparisons with state-of-the-art methods demonstrate the effectiveness and efficiency of our algorithm.

  20. Cost-Effectiveness Analysis: a proposal of new reporting standards in statistical analysis

    PubMed Central

    Bang, Heejung; Zhao, Hongwei

    2014-01-01

    Cost-effectiveness analysis (CEA) is a method for evaluating the outcomes and costs of competing strategies designed to improve health, and has been applied to a variety of different scientific fields. Yet, there are inherent complexities in cost estimation and CEA from statistical perspectives (e.g., skewness, bi-dimensionality, and censoring). The incremental cost-effectiveness ratio that represents the additional cost per one unit of outcome gained by a new strategy has served as the most widely accepted methodology in the CEA. In this article, we call for expanded perspectives and reporting standards reflecting a more comprehensive analysis that can elucidate different aspects of available data. Specifically, we propose that mean and median-based incremental cost-effectiveness ratios and average cost-effectiveness ratios be reported together, along with relevant summary and inferential statistics as complementary measures for informed decision making. PMID:24605979

  1. Incremental Principal Component Analysis Based Outlier Detection Methods for Spatiotemporal Data Streams

    NASA Astrophysics Data System (ADS)

    Bhushan, A.; Sharker, M. H.; Karimi, H. A.

    2015-07-01

    In this paper, we address outliers in spatiotemporal data streams obtained from sensors placed across geographically distributed locations. Outliers may appear in such sensor data due to various reasons such as instrumental error and environmental change. Real-time detection of these outliers is essential to prevent propagation of errors in subsequent analyses and results. Incremental Principal Component Analysis (IPCA) is one possible approach for detecting outliers in such type of spatiotemporal data streams. IPCA has been widely used in many real-time applications such as credit card fraud detection, pattern recognition, and image analysis. However, the suitability of applying IPCA for outlier detection in spatiotemporal data streams is unknown and needs to be investigated. To fill this research gap, this paper contributes by presenting two new IPCA-based outlier detection methods and performing a comparative analysis with the existing IPCA-based outlier detection methods to assess their suitability for spatiotemporal sensor data streams.

  2. Comparative assessment of marginal accuracy of grade II titanium and Ni–Cr alloy before and after ceramic firing: An in vitro study

    PubMed Central

    Patil, Abhijit; Singh, Kishan; Sahoo, Sukant; Suvarna, Suraj; Kumar, Prince; Singh, Anupam

    2013-01-01

    Objective: The aims of the study are to assess the marginal accuracy of base metal and titanium alloy casting and to evaluate the effect of repeated ceramic firing on the marginal accuracy of base metal and titanium alloy castings. Materials and Methods: Twenty metal copings were fabricated with each casting material. Specimens were divided into 4 groups of 10 each representing base metal alloys castings without (Group A) and with metal shoulder margin (Group B), titanium castings without (Group C) and with metal shoulder margin (Group D). The measurement of fit of the metal copings was carried out before the ceramic firing at four different points and the same was followed after porcelain build-up. Results: Significant difference was found when Ni–Cr alloy samples were compared with Grade II titanium samples both before and after ceramic firings. The titanium castings with metal shoulder margin showed highest microgap among all the materials tested. Conclusions: Based on the results that were found and within the limitations of the study design, it can be concluded that there is marginal discrepancy in the copings made from Ni–Cr and Grade II titanium. This marginal discrepancy increased after ceramic firing cycles for both Ni–Cr and Grade II titanium. The comparative statistical analysis for copings with metal-collar showed maximum discrepancy for Group D. The comparative statistical analysis for copings without metal-collar showed maximum discrepancy for Group C. PMID:24926205

  3. Can Aerosol Direct Radiative Effects Account for Analysis Increments of Temperature in the Tropical Atlantic?

    NASA Technical Reports Server (NTRS)

    da Silva, Arlindo M.; Alpert, Pinhas

    2016-01-01

    In the late 1990's, prior to the launch of the Terra satellite, atmospheric general circulation models (GCMs) did not include aerosol processes because aerosols were not properly monitored on a global scale and their spatial distributions were not known well enough for their incorporation in operational GCMs. At the time of the first GEOS Reanalysis (Schubert et al. 1993), long time series of analysis increments (the corrections to the atmospheric state by all available meteorological observations) became readily available, enabling detailed analysis of the GEOS-1 errors on a global scale. Such analysis revealed that temperature biases were particularly pronounced in the Tropical Atlantic region, with patterns depicting a remarkable similarity to dust plumes emanating from the African continent as evidenced by TOMS aerosol index maps. Yoram Kaufman was instrumental encouraging us to pursue this issue further, resulting in the study reported in Alpert et al. (1998) where we attempted to assess aerosol forcing by studying the errors of a the GEOS-1 GCM without aerosol physics within a data assimilation system. Based on this analysis, Alpert et al. (1998) put forward that dust aerosols are an important source of inaccuracies in numerical weather-prediction models in the Tropical Atlantic region, although a direct verification of this hypothesis was not possible back then. Nearly 20 years later, numerical prediction models have increased in resolution and complexity of physical parameterizations, including the representation of aerosols and their interactions with the circulation. Moreover, with the advent of NASA's EOS program and subsequent satellites, atmospheric aerosols are now monitored globally on a routine basis, and their assimilation in global models are becoming well established. In this talk we will reexamine the Alpert et al. (1998) hypothesis using the most recent version of the GEOS-5 Data Assimilation System with assimilation of aerosols. We will explicitly calculate the impact of aerosols on the temperature analysis increments in the tropical Atlantic and assess the extent to which inclusion of atmospheric aerosols have reduced these increments.

  4. CFD Assessment of Aerodynamic Degradation of a Subsonic Transport Due to Airframe Damage

    NASA Technical Reports Server (NTRS)

    Frink, Neal T.; Pirzadeh, Shahyar Z.; Atkins, Harold L.; Viken, Sally A.; Morrison, Joseph H.

    2010-01-01

    A computational study is presented to assess the utility of two NASA unstructured Navier-Stokes flow solvers for capturing the degradation in static stability and aerodynamic performance of a NASA General Transport Model (GTM) due to airframe damage. The approach is to correlate computational results with a substantial subset of experimental data for the GTM undergoing progressive losses to the wing, vertical tail, and horizontal tail components. The ultimate goal is to advance the probability of inserting computational data into the creation of advanced flight simulation models of damaged subsonic aircraft in order to improve pilot training. Results presented in this paper demonstrate good correlations with slope-derived quantities, such as pitch static margin and static directional stability, and incremental rolling moment due to wing damage. This study further demonstrates that high fidelity Navier-Stokes flow solvers could augment flight simulation models with additional aerodynamic data for various airframe damage scenarios.

  5. Dynamics of seismogenic volcanic extrusion at Mount St Helens in 2004-05

    USGS Publications Warehouse

    Iverson, R.M.; Dzurisin, D.; Gardner, C.A.; Gerlach, T.M.; LaHusen, R.G.; Lisowski, M.; Major, J.J.; Malone, S.D.; Messerich, J.A.; Moran, S.C.; Pallister, J.S.; Qamar, A.I.; Schilling, S.P.; Vallance, J.W.

    2006-01-01

    The 2004-05 eruption of Mount St Helens exhibited sustained, near-equilibrium behaviour characterized by relatively steady extrusion of a solid dacite plug and nearly periodic shallow earthquakes. Here we present a diverse data set to support our hypothesis that these earthquakes resulted from stick-slip motion along the margins of the plug as it was forced incrementally upwards by ascending, solidifying, gas-poor magma. We formalize this hypothesis with a dynamical model that reveals a strong analogy between behaviour of the magma-plug system and that of a variably damped oscillator. Modelled stick-slip oscillations have properties that help constrain the balance of forces governing the earthquakes and eruption, and they imply that magma pressure never deviated much from the steady equilibrium pressure. We infer that the volcano was probably poised in a near-eruptive equilibrium state long before the onset of the 2004-05 eruption. ??2006 Nature Publishing Group.

  6. Comparing cost-effectiveness of X-Stop with minimally invasive decompression in lumbar spinal stenosis: a randomized controlled trial.

    PubMed

    Lønne, Greger; Johnsen, Lars Gunnar; Aas, Eline; Lydersen, Stian; Andresen, Hege; Rønning, Roar; Nygaard, Øystein P

    2015-04-15

    Randomized clinical trial with 2-year follow-up. To compare the cost-effectiveness of X-stop to minimally invasive decompression in patients with symptomatic lumbar spinal stenosis. Lumbar spinal stenosis is the most common indication for operative treatment in elderly. Although surgery is more costly than nonoperative treatment, health outcomes for more than 2 years were shown to be significantly better. Surgical treatment with minimally invasive decompression is widely used. X-stop is introduced as another minimally invasive technique showing good results compared with nonoperative treatment. We enrolled 96 patients aged 50 to 85 years, with symptoms of neurogenic intermittent claudication within 250-m walking distance and 1- or 2-level lumbar spinal stenosis, randomized to either minimally invasive decompression or X-stop. Quality-adjusted life-years were based on EuroQol EQ-5D. The hospital unit costs were estimated by means of the top-down approach. Each cost unit was converted into a monetary value by dividing the overall cost by the amount of cost units produced. The analysis of costs and health outcomes is presented by the incremental cost-effectiveness ratio. The study was terminated after a midway interim analysis because of significantly higher reoperation rate in the X-stop group (33%). The incremental cost for X-stop compared with minimally invasive decompression was &OV0556;2832 (95% confidence interval: 1886-3778), whereas the incremental health gain was 0.11 quality-adjusted life-year (95% confidence interval: -0.01 to 0.23). Based on the incremental cost and effect, the incremental cost-effectiveness ratio was &OV0556;25,700. The majority of the bootstrap samples displayed in the northeast corner of the cost-effectiveness plane, giving a 50% likelihood that X-stop is cost-effective at the extra cost of &OV0556;25,700 (incremental cost-effectiveness ratio) for a quality-adjusted life-year. The significantly higher cost of X-stop is mainly due to implant cost and the significantly higher reoperation rate. 2.

  7. International Space Station Increment-2 Quick Look Report

    NASA Technical Reports Server (NTRS)

    Jules, Kenol; Hrovat, Kenneth; Kelly, Eric

    2001-01-01

    The objective of this quick look report is to disseminate the International Space Station (ISS) Increment-2 reduced gravity environment preliminary analysis in a timely manner to the microgravity scientific community. This report is a quick look at the processed acceleration data collected by the Microgravity Acceleration Measurement System (MAMS) during the period of May 3 to June 8, 2001. The report is by no means an exhaustive examination of all the relevant activities, which occurred during the time span mentioned above for two reasons. First, the time span being considered in this report is rather short since the MAMS was not active throughout the time span being considered to allow a detailed characterization. Second, as the name of the report implied, it is a quick look at the acceleration data. Consequently, a more comprehensive report, the ISS Increment-2 report, will be published following the conclusion of the Increment-2 tour of duty. NASA sponsors the MAMS and the Space Acceleration Microgravity System (SAMS) to support microgravity science experiments, which require microgravity acceleration measurements. On April 19, 2001, both the MAMS and the SAMS units were launched on STS-100 from the Kennedy Space Center for installation on the ISS. The MAMS unit was flown to the station in support of science experiments requiring quasisteady acceleration data measurements, while the SAMS unit was flown to support experiments requiring vibratory acceleration data measurement. Both acceleration systems are also used in support of the vehicle microgravity requirements verification. The ISS reduced gravity environment analysis presented in this report uses mostly the MAMS acceleration data measurements (the Increment-2 report will cover both systems). The MAMS has two sensors. The MAMS Orbital Acceleration Research Experiment Sensor Subsystem, which is a low frequency range sensor (up to 1 Hz), is used to characterize the quasi-steady environment for payloads and vehicle. The MAMS High Resolution Acceleration Package is used to characterize the ISS vibratory environment up to 100 Hz. This quick look report presents some selected quasi-steady and vibratory activities recorded by the MAMS during the ongoing ISS Increment-2 tour of duty.

  8. Progression-free survival/time to progression as a potential surrogate for overall survival in HR+, HER2- metastatic breast cancer.

    PubMed

    Forsythe, Anna; Chandiwana, David; Barth, Janina; Thabane, Marroon; Baeck, Johan; Tremblay, Gabriel

    2018-01-01

    Several recent randomized controlled trials (RCTs) in hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) metastatic breast cancer (MBC) have demonstrated significant improvements in progression-free survival (PFS); however, few have reported improvement in overall survival (OS). The surrogacy of PFS or time to progression (TTP) for OS has not been formally investigated in HR+, HER2- MBC. A systematic literature review of RCTs in HR+, HER2- MBC was conducted to identify studies that reported both median PFS/TTP and OS. The correlation between PFS/TTP and OS was evaluated using Pearson's product-moment correlation and Spearman's rank correlation. Subgroup analyses were performed to explore possible reasons for heterogeneity. Errors-in-variables weighted least squares regression (LSR) was used to model incremental OS months as a function of incremental PFS/TTP months. An exploratory analysis investigated the impact of three covariates (chemotherapy vs hormonal/targeted therapy, PFS vs TTP, and first-line therapy vs second-line therapy or greater) on OS prediction. The lower 95% prediction band was used to determine the minimum incremental PFS/TTP months required to predict OS benefit (surrogate threshold effect [STE]). Forty studies were identified. There was a statistically significant correlation between median PFS/TTP and OS (Pearson =0.741, P =0.000; Spearman =0.650, P =0.000). These results proved consistent for chemotherapy and hormonal/targeted therapy. Univariate LSR analysis yielded an R 2 of 0.354 with 1 incremental PFS/TTP month corresponding to 1.13 incremental OS months. Controlling the type of treatment (chemotherapy vs hormonal/targeted therapy), line of therapy (first vs subsequent), and progression measure (PFS vs TTP) led to an improved R 2 of 0.569 with 1 PFS/TTP month corresponding to 0.78 OS months. The STE for OS benefit was 5-6 months of incremental PFS/TTP. We demonstrated a significant association between PFS/TTP and OS, which may justify the use of PFS/TTP as a surrogate for OS benefit in HR+, HER2- MBC.

  9. Writing Stories, Rewriting Identities: Using Journalism Education and Mobile Technologies to Empower Marginalized High School Students

    ERIC Educational Resources Information Center

    Cybart-Persenaire, Alena; Literat, Ioana

    2018-01-01

    This study examines the impact that producing a print newspaper using cell phones had on marginalized students in a high school journalism classroom. Analysis of data from participant observation, artifact analysis and student interviews revealed that a) students negotiated cell phone use for educational purposes, despite school bans on such…

  10. Investigation of the Dominant Factors Influencing the ERA15 Temperature Increments at the Subtropical and Temperate Belts with a Focus over the Eastern Mediterranean Region

    NASA Astrophysics Data System (ADS)

    Alpert, Pinhas; Hirsch-Eshkol, Tali; Baharad, Anat

    2015-04-01

    A Stepwise Multi Regression-based statistics was employed for prioritizing the influence of several factors, both anthropogenic and natural, on the ERA15 temperature increments. The 5 factors which are defined as predictors are;topography, aerosol index (TOMS-AI), atmospheric vertical velocity along with two anthropogenic factors population density and land use changes (LUCI and NDVI trends). The seismic hazard assessment factor was also chosen as the "dummy variable", for validity. Special focus was given to the land use change factor, which was based on two different data sets; HITE data of historical land use/ land cover data and of NDVI trends during 1982- 1991. The Increment Analysis Updates of temperature (IAU(T)), the predicted data, was obtained from the ERA15 (1979-1993) reanalysis. The research consists of both spatial and vertical analyses as well as potential synergies of the selected variables. The spatial geographic analysis is divided into three categories; (a) Coarse region (b) Sub regions analysis and (c) A "small cell" of 4°X4° analysis. It is shown that the following three factors;Topography, TOMS-AI and NDVI are statistically significant (at p<0.05 level) in being the most effective predictors of IAU(T), especially at the 700mb level during March - June. In contrast, the 850mb presents the weakest contribution to IAU(T)probably due to contradictive influence of the various variables at this level. The land use as expressed by the NDVI trends factor, shows a very clear dependency with height, i.e. decreasing, and is one of the most influential factors over the Eastern Mediterranean, which explains up to 20% of the temperature increments in January at 700mb. Moreover, its influence is significant (p<0.05) through all research stages and the different combinations of the multiple regression runs. A major finding not quantified earlier. Reference: T. Hirsch-Eshkol, A. Baharad and P. Alpert, "Investigation of the dominant factors influencing the ERA15 temperature increments at the subtropical and temperate belts with a focus over the Eastern Mediterranean region", Land, 3, 1015-1036; doi:10.3390/land3031015, 2014.

  11. Tooth brushing frequency and risk of new carious lesions.

    PubMed

    Holmes, Richard D

    2016-12-01

    Data sourcesMedline, Embase, CINHAL and the Cochrane databases.Study selectionTwo reviewers selected studies, and case-control, prospective cohort, retrospective cohort and experimental trials evaluating the effect of toothbrushing frequency on the incidence or increment of new carious lesions were considered.Data extraction and synthesisTwo reviewers undertook data abstraction independently using pre-piloted forms. Study quality was assessed using a quality assessment tool for quantitative studies developed by the Effective Public Health Practice Project (EPHPP). Meta-analysis of caries outcomes was carried out using RefMan and meta-regressions undertaken to assess the influence of sample size, follow-up period, caries diagnosis level and study methodological quality.ResultsThirty-three studies were included of which 13 were considered to be methodologically strong, 14 moderate and six weak. Twenty-five studies contributed to the quantitative analysis. Compared with frequent brushers, self-reported infrequent brushers demonstrated a higher incidence of carious lesions, OR=1.50 (95%CI: 1.34 -1.69). The odds of having carious lesions differed little when subgroup analysis was conducted to compare the incidence between ≥2 times/d vs <2 times/d; OR=1.45; (95%CI; 1.21 - 1.74) and ≥1 time/d vs <1 time/d brushers OR=1.56; (95%CI; 1.37 - 1.78). Brushing <2 times/day significantly caused an increment of carious lesions compared with ≥2/day brushing, standardised mean difference [SMD] =0.34; (95%CI; 0.18 - 0.49). Overall, infrequent brushing was associated with an increment of carious lesions, SMD= 0.28; (95%CI; 0.13 - 0.44). Meta-analysis conducted with the type of dentition as subgroups found the effect of infrequent brushing on incidence and increment of carious lesions was higher in deciduous, OR=1.75; (95%CI; 1.49 - 2.06) than permanent dentition OR=1.39; (95% CI: 1.29 -1.49). Meta-regression indicated that none of the included variables influenced the effect estimate.ConclusionsIndividuals who state that they brush their teeth infrequently are at greater risk for the incidence or increment of new carious lesions than those brushing more frequently. The effect is more pronounced in the deciduous than in the permanent dentition. A few studies indicate that this effect is independent of the presence of fluoride in toothpaste.

  12. Flight-determined stability analysis of multiple-input-multiple-output control systems

    NASA Technical Reports Server (NTRS)

    Burken, John J.

    1992-01-01

    Singular value analysis can give conservative stability margin results. Applying structure to the uncertainty can reduce this conservatism. This paper presents flight-determined stability margins for the X-29A lateral-directional, multiloop control system. These margins are compared with the predicted unscaled singular values and scaled structured singular values. The algorithm was further evaluated with flight data by changing the roll-rate-to-aileron command-feedback gain by +/- 20 percent. Minimum eigenvalues of the return difference matrix which bound the singular values are also presented. Extracting multiloop singular values from flight data and analyzing the feedback gain variations validates this technique as a measure of robustness. This analysis can be used for near-real-time flight monitoring and safety testing.

  13. Flight-determined stability analysis of multiple-input-multiple-output control systems

    NASA Technical Reports Server (NTRS)

    Burken, John J.

    1992-01-01

    Singular value analysis can give conservative stability margin results. Applying structure to the uncertainty can reduce this conservatism. This paper presents flight-determined stability margins for the X-29A lateral-directional, multiloop control system. These margins are compared with the predicted unscaled singular values and scaled structured singular values. The algorithm was further evaluated with flight data by changing the roll-rate-to-aileron-command-feedback gain by +/- 20 percent. Also presented are the minimum eigenvalues of the return difference matrix which bound the singular values. Extracting multiloop singular values from flight data and analyzing the feedback gain variations validates this technique as a measure of robustness. This analysis can be used for near-real-time flight monitoring and safety testing.

  14. 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

  15. Cost-effectiveness of salpingotomy and salpingectomy in women with tubal pregnancy (a randomized controlled trial).

    PubMed

    Mol, F; van Mello, N M; Strandell, A; Jurkovic, D; Ross, J A; Yalcinkaya, T M; Barnhart, K T; Verhoeve, H R; Graziosi, G C; Koks, C A; Mol, B W; Ankum, W M; van der Veen, F; Hajenius, P J; van Wely, M

    2015-09-01

    Is salpingotomy cost effective compared with salpingectomy in women with tubal pregnancy and a healthy contralateral tube? Salpingotomy is not cost effective over salpingectomy as a surgical procedure for tubal pregnancy, as its costs are higher without a better ongoing pregnancy rate while risks of persistent trophoblast are higher. Women with a tubal pregnancy treated by salpingotomy or salpingectomy in the presence of a healthy contralateral tube have comparable ongoing pregnancy rates by natural conception. Salpingotomy bears the risk of persistent trophoblast necessitating additional medical or surgical treatment. Repeat ectopic pregnancy occurs slightly more often after salpingotomy compared with salpingectomy. Both consequences imply potentially higher costs after salpingotomy. We performed an economic evaluation of salpingotomy compared with salpingectomy in an international multicentre randomized controlled trial in women with a tubal pregnancy and a healthy contralateral tube. Between 24 September 2004 and 29 November 2011, women were allocated to salpingotomy (n = 215) or salpingectomy (n = 231). Fertility follow-up was done up to 36 months post-operatively. We performed a cost-effectiveness analysis from a hospital perspective. We compared the direct medical costs of salpingotomy and salpingectomy until an ongoing pregnancy occurred by natural conception within a time horizon of 36 months. Direct medical costs included the surgical treatment of the initial tubal pregnancy, readmissions including reinterventions, treatment for persistent trophoblast and interventions for repeat ectopic pregnancy. The analysis was performed according to the intention-to-treat principle. Mean direct medical costs per woman in the salpingotomy group and in the salpingectomy group were €3319 versus €2958, respectively, with a mean difference of €361 (95% confidence interval €217 to €515). Salpingotomy resulted in a marginally higher ongoing pregnancy rate by natural conception compared with salpingectomy leading to an incremental cost-effectiveness ratio €40 982 (95% confidence interval -€130 319 to €145 491) per ongoing pregnancy. Since salpingotomy resulted in more additional treatments for persistent trophoblast and interventions for repeat ectopic pregnancy, the incremental cost-effectiveness ratio was not informative. Costs of any subsequent IVF cycles were not included in this analysis. The analysis was limited to the perspective of the hospital. However, a small treatment benefit of salpingotomy might be enough to cover the costs of subsequent IVF. This uncertainty should be incorporated in shared decision-making. Whether salpingotomy should be offered depends on society's willingness to pay for an additional child. Netherlands Organisation for Health Research and Development, Region Västra Götaland Health & Medical Care Committee. ISRCTN37002267. © The Author 2015. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  16. Circulating levels of C-reactive protein, interleukin-6 and tumor necrosis factor-α and risk of colorectal adenomas: a meta-analysis.

    PubMed

    Zhang, Xiaoqian; Liu, Shanglong; Zhou, Yanbing

    2016-09-27

    Results from publications on inflammatory markers of C-reactive protein (CRP), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) and risk of colorectal adenomas are not consistent. A meta-analysis was conducted to explore the above-mentioned associations. Relevant studies were identified by a search of Embase, Medline and PubMed through February 2016. A random effect model was adopted to combine study-specific odds ratio (OR) and 95% confidence interval (95% CI). Between-study heterogeneity and publications bias were assessed. Dose-response relationships were assessed by restricted cubic splines. Nineteen observational studies were included. For highest vs. lowest levels, results from this meta-analysis did not support an association between circulating levels of CRP [OR (95% CI): 1.15 (0.94-1.40)], IL-6 [1.17 (0.94-1.46)] and TNF-α [0.99 (0.75-1.31)] and risk of colorectal adenomas, respectively. The findings were supported by sensitivity analysis and subgroup analysis. In dose-response analysis, the risk of colorectal adenomas increased by 2% [1.02 (0.97-1.08)] for each 1 mg/L increment in circulation CRP levels, 9% [1.09 (0.91-1.31)] for each 1 ng/L increment in circulation IL-6 levels, and 6% [1.06 (0.93-1.21)] for each 1 pg/mL increment in circulation TNF-α levels. Moderate between-study heterogeneity was found. No evidence of publication bias was found. Circulation levels of CRP, IL-6 and TNF-α might be not useful biomarkers for identifying colorectal adenomas, respectively.

  17. An Analysis of Cost Analysis Methods Used during Contract Evaluation and Source Selection in Government Contracting.

    DTIC Science & Technology

    1986-12-01

    optimal value can be stated as, Marginal Productivity of Marginal Productivity of Good A Good B " Price of Good A Price of Good B This...contractor proposed production costs could be used. _11 i4 W Vi..:. II. CONTRACT PROPOSAL EVALUATION A. PRICE ANALYSIS Price analysis, in its broadest sense...enters the market with a supply function represented by line S2, then the new price will be reestablished at price OP2 and quantity OQ2. Price

  18. Positive Surgical Margins in Favorable-Stage Differentiated Thyroid Cancer.

    PubMed

    Mercado, Catherine E; Drew, Peter A; Morris, Christopher G; Dziegielewski, Peter T; Mendenhall, William M; Amdur, Robert J

    2018-04-16

    The significance of positive margin in favorable-stage well-differentiated thyroid cancer is controversial. We report outcomes of positive-margin patients with a matched-pair comparison to a negative-margin group. A total of 25 patients with classic-histology papillary or follicular carcinoma, total thyroidectomy +/- node dissection, stage T1-3N0-1bM0, positive surgical margin at primary site, adjuvant radioactive iodine (I-131), and age older than 18 years were treated between 2003 and 2013. Endpoints were clinical and biochemical (thyroglobulin-only) recurrence-free survival. Matched-pair analysis involved a 1:1 match with negative-margin cases matched for overall stage and I-131 dose. Recurrence-free survival in positive-margin patients was 71% at 10 years. No patient was successfully salvaged with additional treatment. Only 1 patient died of thyroid cancer. Recurrence-free survival at 10 years was worse with a positive (71%) versus negative (90%) margin (P=0.140). Cure with a microscopically positive margin was suboptimal (71%) despite patients having classic-histology papillary and follicular carcinoma, favorable stage, and moderate-dose I-131 therapy.

  19. 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

  20. 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.

  1. Improved Design of Tunnel Supports : Volume 3 : Finite Element Analysis of the Peachtree Center Station in Atlanta

    DOT National Transportation Integrated Search

    1980-06-01

    Volume 3 contains the application of the three-dimensional (3-D) finite element program, Automatic Dynamic Incremental Nonlinear Analysis (ADINA), which was designed to replace the traditional 2-D plane strain analysis, to a specific location. The lo...

  2. Cost-effectiveness analysis of gemcitabine, S-1 and gemcitabine plus S-1 for treatment of advanced pancreatic cancer based on GEST study.

    PubMed

    Zhou, Jing; Zhao, Rongce; Wen, Feng; Zhang, Pengfei; Tang, Ruilei; Du, Zedong; He, Xiaofeng; Zhang, Jian; Li, Qiu

    2015-04-01

    Gemcitabine (GEM) alone, S-1 alone and gemcitabine plus S-1 (GS) have shown a marginal clinical benefit for the treatment of advanced pancreatic cancer. However, there is no clearly defined optimal cost-effectiveness treatment. The objective of this study was to assess the cost-effectiveness of GEM alone, S-1 alone and GS for the treatment of advanced pancreatic cancer based on GEST study for public payers. A decision model compared GEM alone, S-1 alone and GS. Primary base case data were identified using the GEST study and the literatures. Costs were estimated from West China Hospital, Sichuan University, China, and incremental cost-effectiveness ratios (ICERs) were calculated. Survival benefits were reported in quality-adjusted life-months (QALMs). Sensitive analyses were performed by varying potentially modifiable parameters of the model. The base case analysis showed that the GEM cost $21,912 and yielded survival of 6.93 QALMs, S-1 cost $19,371 and yielded survival of 7.90 QALMs and GS cost $22,943 and yielded survival of 7.46 QALMs in the entire treatment. The one-way sensitivity analyses showed that the ICER of S-1 was driven mostly by the S-1 group utility score of stable state compared with GEM, and the GEM group utility score of progressed state played a key role on the ICER of GS compared with GEM. S-1 represents an attractive cost-effective treatment for advanced pancreatic cancer, given the favorable cost per QALM and improvement in clinical efficacy, especially the limited available treatment options.

  3. Cost-Effectiveness of Haemorrhoidal Artery Ligation versus Rubber Band Ligation for the Treatment of Grade II-III Haemorrhoids: Analysis Using Evidence from the HubBLe Trial.

    PubMed

    Alshreef, Abualbishr; Wailoo, Allan J; Brown, Steven R; Tiernan, James P; Watson, Angus J M; Biggs, Katie; Bradburn, Mike; Hind, Daniel

    2017-09-01

    Haemorrhoids are a common condition, with nearly 30,000 procedures carried out in England in 2014/15, and result in a significant quality-of-life burden to patients and a financial burden to the healthcare system. This study examined the cost effectiveness of haemorrhoidal artery ligation (HAL) compared with rubber band ligation (RBL) in the treatment of grade II-III haemorrhoids. This analyses used data from the HubBLe study, a multicentre, open-label, parallel group, randomised controlled trial conducted in 17 acute UK hospitals between September 2012 and August 2015. A full economic evaluation, including long-term cost effectiveness, was conducted from the UK National Health Service (NHS) perspective. Main outcomes included healthcare costs, quality-adjusted life-years (QALYs) and recurrence. Cost-effectiveness results were presented in terms of incremental cost per QALY gained and cost per recurrence avoided. Extrapolation analysis for 3 years beyond the trial follow-up, two subgroup analyses (by grade of haemorrhoids and recurrence following RBL at baseline), and various sensitivity analyses were undertaken. In the primary base-case within-trial analysis, the incremental total mean cost per patient for HAL compared with RBL was £1027 (95% confidence interval [CI] £782-£1272, p < 0.001). The incremental QALYs were 0.01 QALYs (95% CI -0.02 to 0.04, p = 0.49). This generated an incremental cost-effectiveness ratio (ICER) of £104,427 per QALY. In the extrapolation analysis, the estimated probabilistic ICER was £21,798 per QALY. Results from all subgroup and sensitivity analyses did not materially change the base-case result. Under all assessed scenarios, the HAL procedure was not cost effective compared with RBL for the treatment of grade II-III haemorrhoids at a cost-effectiveness threshold of £20,000 per QALY; therefore, economically, its use in the NHS should be questioned.

  4. The role of tectonic inheritance in the morphostructural evolution of the Galicia continental margin and adjacent abyssal plains from digital bathymetric model (DBM) analysis (NW Spain)

    NASA Astrophysics Data System (ADS)

    Maestro, A.; Jané, G.; Llave, E.; López-Martínez, J.; Bohoyo, F.; Druet, M.

    2018-06-01

    The identification of recent major tectonic structures in the Galicia continental margin and adjacent abyssal plains was carried out by means of a quantitative analysis of the linear structures having bathymetric expression on the seabed. It was possible to identify about 5800 lineaments throughout the entire study area, of approximately 271,500 km2. Most lineaments are located in the Charcot and Coruña highs, in the western sector of the Galicia Bank, in the area of the Marginal Platforms and in the northern sector of the margin. Analysis of the lineament orientations shows a predominant NE-SW direction and three relative maximum directions: NW-SE, E-W and N-S. The total length of the lineaments identified is over 44,000 km, with a mode around 5000 m and an average length of about 7800 m. In light of different tectonic studies undertaken in the northwestern margin of the Iberian Peninsula, we establish that the lineaments obtained from analysis of the digital bathymetric model of the Galicia continental margin and adjacent abyssal plains would correspond to fracture systems. In general, the orientation of lineaments corresponds to main faults, tectonic structures following the directions of ancient faults that resulted from late stages of the Variscan orogeny and Mesozoic extension phases related to Triassic rifting and Upper Jurassic to Early Cretaceous opening of the North Atlantic Ocean. The N-S convergence between Eurasian and African plates since Palaeogene times until the Miocene, and NW-SE convergence from Neogene to present, reactivated the Variscan and Mesozoic fault systems and related physiography.

  5. Loss of Coolant Accident (LOCA) / Emergency Core Coolant System (ECCS Evaluation of Risk-Informed Margins Management Strategies for a Representative Pressurized Water Reactor (PWR)

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

    Szilard, Ronaldo Henriques

    A Risk Informed Safety Margin Characterization (RISMC) toolkit and methodology are proposed for investigating nuclear power plant core, fuels design and safety analysis, including postulated Loss-of-Coolant Accident (LOCA) analysis. This toolkit, under an integrated evaluation model framework, is name LOCA toolkit for the US (LOTUS). This demonstration includes coupled analysis of core design, fuel design, thermal hydraulics and systems analysis, using advanced risk analysis tools and methods to investigate a wide range of results.

  6. Evaluation of marginal and internal adaptation of hybrid and nanoceramic systems with microcomputed tomography: An in vitro study.

    PubMed

    Yildirim, Güler; Uzun, Ismail H; Keles, Ali

    2017-08-01

    The accuracy of recently introduced chairside computer-aided design and computer-aided manufacturing (CAD-CAM) blocks is not well established, and marginal integrity and internal adaptation are not known. The purpose of this in vitro study was to evaluate the marginal and internal adaptation of hybrid and nanoceramics using microcomputed tomography (μ-CT). The marginal and internal adaptation of 3 polymer-infiltrated ceramic-network (PICN) materials (Vita Enamic [VE]; Lava Ultimate [LU]; Vita Suprinity [VS]) were compared with lithium disilicate (IPS e.max.CAD, IPS). Ninety-six specimens (48 dies and 48 crowns) were prepared (n=12 each group) using a chairside CAD-CAM system. The restorations were scanned with μ-CT, with 160 measurements made for each crown, and used in 2-dimensional (2D) analysis. The marginal adaptation of marginal discrepancy (MD), absolute marginal discrepancy (AMD), internal adaptation of shoulder area (SA), axial space (AS), and occlusal space (OS) were compared using appropriate statistical analysis methods (α=.05). Cement volumes were compared using 3D analysis. The IPS blocks showed higher MD (130 μm), AMD (156 μm), SA (111 μm) (P<.05), AS (52 μm), and OS (192 μm) than the other blocks (P<.01). The adaptation values of VS were significantly lower than those of the IPS block (P<.05). The adaption values of the LU and VE blocks were significantly lower than those of others (P<.01) but were statistically similar to one another (P>.05). IPS had the largest cement space at 18 mm 3 (P<.01). The marginal and internal adaptation values were within a clinically acceptable range for all 3 hybrids and nanoceramics tested. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  7. Economic analysis of human papillomavirus triage, repeat cytology, and immediate colposcopy in management of women with minor cytological abnormalities in Sweden.

    PubMed

    Ostensson, Ellinor; Fröberg, Maria; Hjerpe, Anders; Zethraeus, Niklas; Andersson, Sonia

    2010-10-01

    To assess the cost-effectiveness of using human papillomavirus testing (HPV triage) in the management of women with minor cytological abnormalities in Sweden. An economic analysis based on a clinical trial, complemented with data from published meta-analyses on accuracy of HPV triage. The study takes perspective of the Swedish healthcare system. The Swedish population-based cervical cancer screening program. A decision analytic model was constructed to evaluate cost-effectiveness of HPV triage compared to repeat cytology and immediate colposcopy with biopsy, stratifying by index cytology (ASCUS = atypical squamous cells of undetermined significance, and LSIL = low-grade squamous intraepithelial lesion) and age (23-60 years, <30 years and ≥30 years). Costs, incremental cost, incremental effectiveness and incremental cost per additional high-grade lesion (CIN2+) detected. For women with ASCUS ≥30 years, HPV triage is the least costly alternative, whereas immediate colposcopy with biopsy provides the most effective option at an incremental cost-effectiveness ratio (ICER) of SEK 2,056 per additional case of CIN2+ detected. For LSIL (all age groups) and ASCUS (23-60 years and <30 years), HPV triage is dominated by immediate colposcopy and biopsy. Model results were sensitive to HPV test cost changes. With improved HPV testing techniques at lower costs, HPV triage can become a cost-effective alternative for follow-up of minor cytological abnormalities. Today, immediate colposcopy with biopsy is a cost-effective alternative compared to HPV triage and repeat cytology.

  8. Histomorphometric analysis of knee synovial membrane in dogs undergoing leg lengthening by classic Ilizarov method and rapid automatic distraction.

    PubMed

    Stupina, Tatyana A; Shchudlo, Mikhail M; Shchudlo, Natalia A; Stepanov, Mikhail A

    2013-10-01

    This pilot study aimed to test the theory that different lengthening methods affect the microscopic structure of knee joint synovium in diverse ways. This was a descriptive and analytical cross-sectional study of synovium carried out in two experimental models of canine leg lengthening using the Ilizarov fixator. Group 1 (n = 6) used manual gradual distraction most commonly used in clinical practice at one millimetre/day divided into four equal increments, 0.25 mm at each increment. Group 2 (n = 7) used an increased rate of automatic distraction at three millimetres/day divided in 120 increments, 0.025 mm at each increment. At the end of distraction and after fixator removal, the animals were euthanised. Control was via intact dogs. The thickness of the synovial lining layer, number of synovial cell rows, and numerical density of subsynovial microvessels were assessed in digital images for semiautomated computerised analysis of semi-thin sections stained with toluidine blue and methylene blue-basic fuchsin. Comparison of synovitis manifestation was made with grading scale. The vascular and nerve changes in the subsynovial layer were also compared. Group 1 developed marked synovitis, synovium hypervascularisation, degeneration of the nerve fibres in subsynovial nerves with the tendency to regeneration. Group 2 had moderate to mild degree of synovitis with progressive degenerative changes in subsynovial vessels and nerves. Both methods used are unfavourable for the state of the joint synovium, but modify it in different ways.

  9. Number needed to treat and costs per responder among biologic treatments for moderate-to-severe psoriasis: a network meta-analysis.

    PubMed

    Armstrong, April W; Betts, Keith A; Signorovitch, James E; Sundaram, Murali; Li, Junlong; Ganguli, Arijit X; Wu, Eric Q

    2018-04-23

    The clinical benefits of biologic therapies for moderate-to-severe psoriasis are well established, but wide variations exist in patient response. To determine the number needed to treat (NNT) to achieve a 75% and 90% reduction in the Psoriasis Area and Severity Index (PASI-75/90) with FDA-approved agents and evaluate the incremental cost per PASI-75 or PASI-90 responder. The relative probabilities of achieving PASI-75 and PASI-90, as well as NNTs, were estimated using a network meta-analysis. Costs (2017 USD) included drug acquisition and administration. The incremental cost per PASI-75 or PASI-90 responder for each treatment was estimated for the clinical trial period, and annually. Compared with supportive care, the NNT to achieve PASI-75 was 1.18 for ixekizumab, 1.29 for secukinumab 300 mg, 1.37 for infliximab, 1.48 for adalimumab, 1.53 for secukinumab 150 mg, 1.58 for ustekinumab, 2.25 for etanercept, and 3.71 for apremilast. The one-year incremental cost per PASI-75 responder relative to supportive care was $59,830 for infliximab, $88,775 for secukinumab 300 mg, $91,837 for adalimumab, $95,898 for ixekizumab, $97,363 for ustekinumab, $105,131 for secukinumab 150 mg, $129,665 for apremilast, and $159,328 for etanercept. Results were similar for PASI-90. The NNT and incremental cost per responder are meaningful ways to assess comparative effectiveness and cost effectiveness among psoriasis treatments.

  10. Use of high-frequency peak in spectral analysis of heart rate increment to improve screening of obstructive sleep apnoea.

    PubMed

    Poupard, Laurent; Court-Fortune, Isabelle; Pichot, Vincent; Chouchou, Florian; Barthélémy, Jean-Claude; Roche, Frédéric

    2011-12-01

    Several studies have correlated the ratio of the very low frequency power spectral density of heart rate increment (%VLFI) with obstructive sleep apnoea syndrome (OSAS). However, patients with impaired heart rate variability may exhibit large variations of heart rate increment (HRI) spectral pattern and alter the screening accuracy of the method. To overcome this limitation, the present study uses the high-frequency increment (HFI) peak in the HRI spectrum, which corresponds to the respiratory influence on RR variations over the frequency range 0.2 to 0.4 Hz. We evaluated 288 consecutive patients referred for snoring, observed nocturnal breathing cessation and/or daytime sleepiness. Patients were classified as OSAS if their apnoea plus hypopnoea index (AHI) during polysomnography exceeded 15 events per hour. Synchronized electrocardiogram Holter monitoring allowed HRI analysis. Using a %VLFI threshold >2.4% for identifying the presence of OSAS, sensitivity for OSAS was 74.9%, specificity 51%, positive predictive value 54.9% and negative predictive value 71.7% (33 false negative subjects). Using threshold for %VLFI >2.4% and HFI peak position >0.4 Hz, negative predictive value increased to 78.2% while maintaining specificity at 50.6%. Among 11 subjects with %VLFI <2.4% and HFI peak >0.4 Hz, nine demonstrated moderate to severe OSAS (AHI >30). HFI represents a minimal physiological criterion for applying %VLFI by ensuring that heart rate variations are band frequency limited.

  11. Assessment of Rainfall-induced Landslide Potential and Spatial Distribution

    NASA Astrophysics Data System (ADS)

    Chen, Yie-Ruey; Tsai, Kuang-Jung; Chen, Jing-Wen; Chiang, Jie-Lun; Hsieh, Shun-Chieh; Chue, Yung-Sheng

    2016-04-01

    Recently, due to the global climate change, most of the time the rainfall in Taiwan is of short duration but with high intensity. Due to Taiwan's steep terrain, rainfall-induced landslides often occur and lead to human causalities and properties loss. Taiwan's government has invested huge reconstruction funds to the affected areas. However, after rehabilitation they still face the risk of secondary sediment disasters. Therefore, this study assesses rainfall-induced (secondary) landslide potential and spatial distribution in watershed of Southern Taiwan under extreme climate change. The study areas in this research are Baolai and Jianshan villages in the watershed of the Laonongxi River Basin in the Southern Taiwan. This study focused on the 3 years after Typhoon Morakot (2009 to 2011). During this period, the study area experienced six heavy rainfall events including five typhoons and one heavy rainfall. The genetic adaptive neural network, texture analysis and GIS were implemented in the analysis techniques for the interpretation of satellite images and to obtain surface information and hazard log data and to analyze land use change. A multivariate hazards evaluation method was applied to quantitatively analyze the weights of various natural environmental and slope development hazard factors. Furthermore, this study established a slope landslide potential assessment model and depicted a slope landslide potential diagram by using the GIS platform. The interaction between (secondary) landslide mechanism, scale, and location was analyzed using association analysis of landslide historical data and regional environmental characteristics. The results of image classification before and after six heavy rainfall events show that the values of coefficient of agreement are at medium-high level. By multivariate hazards evaluation method, geology and the effective accumulative rainfall (EAR) are the most important factors. Slope, distance from fault, aspect, land disturbance, and elevation are the secondary important factors. Under the different rainfall, the greater the average of EAR, the more the landslide occurrence and area increments. The determination coefficients of trend lines on the charts of the average of EAR versus number and area of landslide increment are 0.83 and 0.92, respectively. The relations between landslide potential level, degree of land disturbance, and the ratio of number and area of landslide increment corresponding six heavy rainfall events are positive and the determination coefficients of trend lines are 0.82 and 0.72, respectively. The relation between the average of EAR and the area of landslide increment corresponding five heavy rainfall events (excluding Morakot) is positive and the determination coefficient of trend line is 0.98. Furthermore, the relation between the area increment of secondary landslide, average of EAR or the slope disturbance is positive. Under the same slope disturbance, the greater the EAR, the more the area increment of secondary landslide. Contrarily, under the same EAR, the greater the slope disturbance, the more the area increment of secondary landslide. The results of the analysis of this study can be a reference for the government for subsequent countermeasures for slope sediment disaster sensitive area to reduce the number of casualties and significantly reduce the social cost of post-disaster.

  12. Different CAD/CAM-processing routes for zirconia restorations: influence on fitting accuracy.

    PubMed

    Kohorst, Philipp; Junghanns, Janet; Dittmer, Marc P; Borchers, Lothar; Stiesch, Meike

    2011-08-01

    The aim of the present in vitro study was to evaluate the influence of different processing routes on the fitting accuracy of four-unit zirconia fixed dental prostheses (FDPs) fabricated by computer-aided design/computer-aided manufacturing (CAD/CAM). Three groups of zirconia frameworks with ten specimens each were fabricated. Frameworks of one group (CerconCAM) were produced by means of a laboratory CAM-only system. The other frameworks were made with different CAD/CAM systems; on the one hand by in-laboratory production (CerconCAD/CAM) and on the other hand by centralized production in a milling center (Compartis) after forwarding geometrical data. Frameworks were then veneered with the recommended ceramics, and marginal accuracy was determined using a replica technique. Horizontal marginal discrepancy, vertical marginal discrepancy, absolute marginal discrepancy, and marginal gap were evaluated. Statistical analyses were performed by one-way analysis of variance (ANOVA), with the level of significance chosen at 0.05. Mean horizontal discrepancies ranged between 22 μm (CerconCAM) and 58 μm (Compartis), vertical discrepancies ranged between 63 μm (CerconCAD/CAM) and 162 μm (CerconCAM), and absolute marginal discrepancies ranged between 94 μm (CerconCAD/CAM) and 181 μm (CerconCAM). The marginal gap varied between 72 μm (CerconCAD/CAM) and 112 μm (CerconCAM, Compartis). Statistical analysis revealed that, with all measurements, the marginal accuracy of the zirconia FDPs was significantly influenced by the processing route used (p < 0.05). Within the limitations of this study, all restorations showed a clinically acceptable marginal accuracy; however, the results suggest that the CAD/CAM systems are more precise than the CAM-only system for the manufacture of four-unit FDPs.

  13. Estimation of Inherent Safety Margins in Loaded Commercial Spent Nuclear Fuel Casks

    DOE PAGES

    Banerjee, Kaushik; Robb, Kevin R.; Radulescu, Georgeta; ...

    2016-06-15

    We completed a novel assessment to determine the unquantified and uncredited safety margins (i.e., the difference between the licensing basis and as-loaded calculations) available in as-loaded spent nuclear fuel (SNF) casks. This assessment was performed as part of a broader effort to assess issues and uncertainties related to the continued safety of casks during extended storage and transportability following extended storage periods. Detailed analyses crediting the actual as-loaded cask inventory were performed for each of the casks at three decommissioned pressurized water reactor (PWR) sites to determine their characteristics relative to regulatory safety criteria for criticality, thermal, and shielding performance.more » These detailed analyses were performed in an automated fashion by employing a comprehensive and integrated data and analysis tool—Used Nuclear Fuel-Storage, Transportation & Disposal Analysis Resource and Data System (UNF-ST&DARDS). Calculated uncredited criticality margins from 0.07 to almost 0.30 Δk eff were observed; calculated decay heat margins ranged from 4 to almost 22 kW (as of 2014); and significant uncredited transportation dose rate margins were also observed. The results demonstrate that, at least for the casks analyzed here, significant uncredited safety margins are available that could potentially be used to compensate for SNF assembly and canister structural performance related uncertainties associated with long-term storage and subsequent transportation. The results also suggest that these inherent margins associated with how casks are loaded could support future changes in cask licensing to directly or indirectly credit the margins. Work continues to quantify the uncredited safety margins in the SNF casks loaded at other nuclear reactor sites.« less

  14. Evaluation and comparison of the marginal adaptation of two different substructure materials.

    PubMed

    Karaman, Tahir; Ulku, Sabiha Zelal; Zengingul, Ali Ihsan; Guven, Sedat; Eratilla, Veysel; Sumer, Ebru

    2015-06-01

    In this study, we aimed to evaluate the amount of marginal gap with two different substructure materials using identical margin preparations. Twenty stainless steel models with a chamfer were prepared with a CNC device. Marginal gap measurements of the galvano copings on these stainless steel models and Co-Cr copings obtained by a laser-sintering method were made with a stereomicroscope device before and after the cementation process and surface properties were evaluated by scanning electron microscopy (SEM). A dependent t-test was used to compare the mean of the two groups for normally distributed data, and two-way variance analysis was used for more than two data sets. Pearson's correlation analysis was also performed to assess relationships between variables. According to the results obtained, the marginal gap in the galvano copings before cementation was measured as, on average, 24.47 ± 5.82 µm before and 35.11 ± 6.52 µm after cementation; in the laser-sintered Co-Cr structure, it was, on average, 60.45 ± 8.87 µm before and 69.33 ± 9.03 µm after cementation. A highly significant difference (P<.001) was found in marginal gap measurements of galvano copings and a significant difference (P<.05) was found in marginal gap measurements of the laser-sintered Co-Cr copings. According to the SEM examination, surface properties of laser sintered Co-Cr copings showed rougher structure than galvano copings. The galvano copings showed a very smooth surface. Marginal gaps values of both groups before and after cementation were within the clinically acceptable level. The smallest marginal gaps occurred with the use of galvano copings.

  15. Evaluation and comparison of the marginal adaptation of two different substructure materials

    PubMed Central

    Karaman, Tahir; Ulku, Sabiha Zelal; Zengingul, Ali Ihsan; Eratilla, Veysel; Sumer, Ebru

    2015-01-01

    PURPOSE In this study, we aimed to evaluate the amount of marginal gap with two different substructure materials using identical margin preparations. MATERIALS AND METHODS Twenty stainless steel models with a chamfer were prepared with a CNC device. Marginal gap measurements of the galvano copings on these stainless steel models and Co-Cr copings obtained by a laser-sintering method were made with a stereomicroscope device before and after the cementation process and surface properties were evaluated by scanning electron microscopy (SEM). A dependent t-test was used to compare the mean of the two groups for normally distributed data, and two-way variance analysis was used for more than two data sets. Pearson's correlation analysis was also performed to assess relationships between variables. RESULTS According to the results obtained, the marginal gap in the galvano copings before cementation was measured as, on average, 24.47 ± 5.82 µm before and 35.11 ± 6.52 µm after cementation; in the laser-sintered Co-Cr structure, it was, on average, 60.45 ± 8.87 µm before and 69.33 ± 9.03 µm after cementation. A highly significant difference (P<.001) was found in marginal gap measurements of galvano copings and a significant difference (P<.05) was found in marginal gap measurements of the laser-sintered Co-Cr copings. According to the SEM examination, surface properties of laser sintered Co-Cr copings showed rougher structure than galvano copings. The galvano copings showed a very smooth surface. CONCLUSION Marginal gaps values of both groups before and after cementation were within the clinically acceptable level. The smallest marginal gaps occurred with the use of galvano copings. PMID:26140178

  16. Positive surgical margins after robotic assisted radical prostatectomy: a multi-institutional study.

    PubMed

    Patel, Vipul R; Coelho, Rafael F; Rocco, Bernardo; Orvieto, Marcelo; Sivaraman, Ananthakrishnan; Palmer, Kenneth J; Kameh, Darien; Santoro, Luigi; Coughlin, Geoff D; Liss, Michael; Jeong, Wooju; Malcolm, John; Stern, Joshua M; Sharma, Saurabh; Zorn, Kevin C; Shikanov, Sergey; Shalhav, Arieh L; Zagaja, Gregory P; Ahlering, Thomas E; Rha, Koon H; Albala, David M; Fabrizio, Michael D; Lee, David I; Chauhan, Sanket

    2011-08-01

    Positive surgical margins are an independent predictive factor for biochemical recurrence after radical prostatectomy. We analyzed the incidence of and associative factors for positive surgical margins in a multi-institutional series of 8,418 robotic assisted radical prostatectomies. We analyzed the records of 8,418 patients who underwent robotic assisted radical prostatectomy at 7 institutions. Of the patients 323 had missing data on margin status. Positive surgical margins were categorized into 4 groups, including apex, bladder neck, posterolateral and multifocal. The records of 6,169 patients were available for multivariate analysis. The variables entered into the logistic regression models were age, body mass index, preoperative prostate specific antigen, biopsy Gleason score, prostate weight and pathological stage. A second model was built to identify predictive factors for positive surgical margins in the subset of patients with organ confined disease (pT2). The overall positive surgical margin rate was 15.7% (1,272 of 8,095 patients). The positive surgical margin rate for pT2 and pT3 disease was 9.45% and 37.2%, respectively. On multivariate analysis pathological stage (pT2 vs pT3 OR 4.588, p<0.001) and preoperative prostate specific antigen (4 or less vs greater than 10 ng/ml OR 2.918, p<0.001) were the most important independent predictive factors for positive surgical margins after robotic assisted radical prostatectomy. Increasing prostate weight was associated with a lower risk of positive surgical margins after robotic assisted radical prostatectomy (OR 0.984, p<0.001) and a higher body mass index was associated with a higher risk of positive surgical margins (OR 1.032, p<0.001). For organ confined disease preoperative prostate specific antigen was the most important factor that independently correlated with positive surgical margins (4 or less vs greater than 10 ng/ml OR 3.8, p<0.001). The prostatic apex followed by a posterolateral site was the most common location of positive surgical margins after robotic assisted radical prostatectomy. Factors that correlated with cancer aggressiveness, such as pathological stage and preoperative prostate specific antigen, were the most important factors independently associated with an increased risk of positive surgical margins after robotic assisted radical prostatectomy. Copyright © 2011 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  17. A Pilot Cost-Effectiveness Analysis of Treatments in Newly Diagnosed High-Grade Gliomas: The Example of 5-Aminolevulinic Acid Compared With White-Light Surgery

    PubMed Central

    Alves, Marta; Castel-Branco, Marta; Stummer, Walter

    2015-01-01

    BACKGROUND: High-grade gliomas are aggressive, incurable tumors characterized by extensive diffuse invasion of the normal brain parenchyma. Novel therapies at best prolong survival; their costs are formidable and benefit is marginal. Economic restrictions thus require knowledge of the cost-effectiveness of treatments. Here, we show the cost-effectiveness of enhanced resections in malignant glioma surgery using a well-characterized tool for intraoperative tumor visualization, 5-aminolevulinic acid (5-ALA). OBJECTIVE: To evaluate the cost-effectiveness of 5-ALA fluorescence-guided neurosurgery compared with white-light surgery in adult patients with newly diagnosed high-grade glioma, adopting the perspective of the Portuguese National Health Service. METHODS: We used a Markov model (cohort simulation). Transition probabilities were estimated with the use of data from 1 randomized clinical trial and 1 noninterventional prospective study. Utility values and resource use were obtained from published literature and expert opinion. Unit costs were taken from official Portuguese reimbursement lists (2012 values). The health outcomes considered were quality-adjusted life-years, life-years, and progression-free life-years. Extensive 1-way and probabilistic sensitivity analyses were performed. RESULTS: The incremental cost-effectiveness ratios are below €10 000 in all evaluated outcomes, being around €9100 per quality-adjusted life-year gained, €6700 per life-year gained, and €8800 per progression-free life-year gained. The probability of 5-ALA fluorescence-guided surgery cost-effectiveness at a threshold of €20000 is 96.0% for quality-adjusted life-year, 99.6% for life-year, and 98.8% for progression-free life-year. CONCLUSION: 5-ALA fluorescence-guided surgery appears to be cost-effective in newly diagnosed high-grade gliomas compared with white-light surgery. This example demonstrates cost-effectiveness analyses for malignant glioma surgery to be feasible on the basis of existing data. ABBREVIATIONS: 5-ALA, 5-aminolevulinic acid ICER, incremental cost-effectiveness ratio LY, life-year PFLY, progression-free life-year QALY, quality-adjusted life-year PMID:25714513

  18. Cost-effectiveness of an electronic clinical decision support system for improving quality of antenatal and childbirth care in rural Tanzania: an intervention study.

    PubMed

    Saronga, Happiness Pius; Duysburgh, Els; Massawe, Siriel; Dalaba, Maxwell Ayindenaba; Wangwe, Peter; Sukums, Felix; Leshabari, Melkizedeck; Blank, Antje; Sauerborn, Rainer; Loukanova, Svetla

    2017-08-07

    QUALMAT project aimed at improving quality of maternal and newborn care in selected health care facilities in three African countries. An electronic clinical decision support system was implemented to support providers comply with established standards in antenatal and childbirth care. Given that health care resources are limited and interventions differ in their potential impact on health and costs (efficiency), this study aimed at assessing cost-effectiveness of the system in Tanzania. This was a quantitative pre- and post- intervention study involving 6 health centres in rural Tanzania. Cost information was collected from health provider's perspective. Outcome information was collected through observation of the process of maternal care. Incremental cost-effectiveness ratios for antenatal and childbirth care were calculated with testing of four models where the system was compared to the conventional paper-based approach to care. One-way sensitivity analysis was conducted to determine whether changes in process quality score and cost would impact on cost-effectiveness ratios. Economic cost of implementation was 167,318 USD, equivalent to 27,886 USD per health center and 43 USD per contact. The system improved antenatal process quality by 4.5% and childbirth care process quality by 23.3% however these improvements were not statistically significant. Base-case incremental cost-effectiveness ratios of the system were 2469 USD and 338 USD per 1% change in process quality for antenatal and childbirth care respectively. Cost-effectiveness of the system was sensitive to assumptions made on costs and outcomes. Although the system managed to marginally improve individual process quality variables, it did not have significant improvement effect on the overall process quality of care in the short-term. A longer duration of usage of the electronic clinical decision support system and retention of staff are critical to the efficiency of the system and can reduce the invested resources. Realization of gains from the system requires effective implementation and an enabling healthcare system. Registered clinical trial at www.clinicaltrials.gov ( NCT01409824 ). Registered May 2009.

  19. 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.

  20. Vertical motions of passive margins of Greenland: influence of ice sheet, glacial erosion, and sediment transport

    NASA Astrophysics Data System (ADS)

    Souche, A.; Medvedev, S.; Hartz, E. H.

    2009-04-01

    The sub-ice topography of Greenland is characterized by a central depression below the sea level and by elevated (in some places significantly) margins. Whereas the central depression may be explained by significant load of the Greenland ice sheet, the origin of the peripheral relief remains unclear. We analyze the influence of formation of the ice sheet and carving by glacial erosion on the evolution of topography along the margins of Greenland. Our analysis shows that: (1) The heavy ice loading in the central part of Greenland and consecutive peripheral bulging has a negligible effect on amplitude of the uplifted Greenland margins. (2) First order estimates of uplift due to isostatic readjustment caused by glacial erosion and unloading in the fjord systems is up to 1.1 km. (3) The increase of accuracy of topographic data (comparing several data sets of resolution with grid size from 5 km to 50 m) results in increase of the isostatic response in the model. (4) The analysis of mass redistribution during erosion-sedimentation process and data on age of offshore sediments allows us to estimate the timing of erosion along the margins of Greenland. This ongoing analysis, however, requires careful account for the link between sources (localized glacial erosion) and sinks (offshore sedimentary basins around Greenland).

  1. Carpal tunnel syndrome, the search for a cost-effective surgical intervention: a randomised controlled trial.

    PubMed Central

    Lorgelly, Paula K.; Dias, Joseph J.; Bradley, Mary J.; Burke, Frank D.

    2005-01-01

    OBJECTIVE: There is insufficient evidence regarding the clinical and cost-effectiveness of surgical interventions for carpal tunnel syndrome. This study evaluates the cost, effectiveness and cost-effectiveness of minimally invasive surgery compared with conventional open surgery. PATIENTS AND METHODS: 194 sufferers (208 hands) of carpal tunnel syndrome were randomly assigned to each treatment option. A self-administered questionnaire assessed the severity of patients' symptoms and functional status pre- and postoperatively. Treatment costs were estimated from resource use and hospital financial data. RESULTS: Minimally invasive carpal tunnel decompression is marginally more effective than open surgery in terms of functional status, but not significantly so. Little improvement in symptom severity was recorded for either intervention. Minimally invasive surgery was found to be significantly more costly than open surgery. The incremental cost effectiveness ratio for functional status was estimated to be 197 UK pounds, such that a one percentage point improvement in functioning costs 197 UK pounds when using the minimally invasive technique. CONCLUSIONS: Minimally invasive carpal tunnel decompression appears to be more effective but more costly. Initial analysis suggests that the additional expense for such a small improvement in function and no improvement in symptoms would not be regarded as value-for-money, such that minimally invasive carpal tunnel release is unlikely to be considered a cost-effective alternative to the traditional open surgery procedure. PMID:15720906

  2. Are Early-Life Socioeconomic Conditions Directly Related to Birth Outcomes? Grandmaternal Education, Grandchild Birth Weight, and Associated Bias Analyses

    PubMed Central

    Huang, Jonathan Y.; Gavin, Amelia R.; Richardson, Thomas S.; Rowhani-Rahbar, Ali; Siscovick, David S.; Enquobahrie, Daniel A.

    2015-01-01

    Grandmaternal education may be related to grandchild birth weight (GBW) through maternal early-life development; however, conventional regression models may be endogenously confounded. Alternative models employing explicit structural assumptions may provide incrementally clearer evidence. We used data from the US National Longitudinal Study of Adolescent to Adult Health (1995–2009; 1,681 mother-child pairs) to estimate “direct effects” of grandmaternal educational level (less than high school, high school diploma or equivalent, or college degree) at the time of the mother's birth on GBW, adjusted for maternal life-course factors: maltreatment as a child, education and income as an adult, prepregnancy overweight, and prenatal smoking. Using conventional and marginal structural model (MSM) approaches, we estimated 54-g (95% confidence interval: −14.0, 122.1) and 87-g (95% confidence interval: 10.9, 162.5) higher GBWs per increase in educational level, respectively. The MSM allowed simultaneous mediation by and adjustment for prepregnancy overweight. Estimates were insensitive to alternate structural assumptions and mediator parameterizations. Bias analysis suggested that a single unmeasured confounder would have to have a strong influence on GBW (approximately 150 g) or be greatly imbalanced across exposure groups (approximately 25%) to completely explain the findings. Coupling an MSM with sensitivity analyses provides some evidence that maternal early-life socioeconomic environment is directly associated with offspring birth weight. PMID:26283086

  3. Clopidogrel versus aspirin in patients with recent ischemic stroke and established peripheral artery disease: an economic evaluation in a Chinese setting.

    PubMed

    Li, Te; Liu, Maobai; Ben, He; Xu, Zhenxing; Zhong, Han; Wu, Bin

    2015-06-01

    Clopidogrel or aspirin are indicated for patients with recent ischemic stroke (IS) or established peripheral artery disease (PAD). We compared the cost effectiveness of clopidogrel with that of aspirin in Chinese patients with recent IS or established PAD. A discrete-event simulation was developed to evaluate the economic implications of secondary prevention with clopidogrel versus aspirin. All available evidence was derived from clinical studies. Costs from a Chinese healthcare perspective in 2013 US dollars and quality-adjusted life-years (QALYs) were projected over patients' lifetimes. Uncertainties were addressed using sensitivity analyses. Compared with aspirin, clopidogrel yielded a marginally increased life expectancy by 0.46 and 0.21 QALYs at an incremental cost-effectiveness ratio of $US5246 and $US9890 per QALY in patients with recent IS and established PAD, respectively. One-way sensitivity analyses showed that the evaluation of patients with PAD and recent IS was robust except for the parameter of patient age. Given a willingness-to-pay of $US19,877 per QALY gained, clopidogrel had a probability of 90 and 68% of being cost effective in the recent IS or established PAD subgroups compared with aspirin, respectively. The analysis suggests that clopidogrel for secondary prevention is cost effective for patients with either PAD or recent IS in a Chinese setting in comparison with aspirin.

  4. Margin and sensitivity methods for security analysis of electric power systems

    NASA Astrophysics Data System (ADS)

    Greene, Scott L.

    Reliable operation of large scale electric power networks requires that system voltages and currents stay within design limits. Operation beyond those limits can lead to equipment failures and blackouts. Security margins measure the amount by which system loads or power transfers can change before a security violation, such as an overloaded transmission line, is encountered. This thesis shows how to efficiently compute security margins defined by limiting events and instabilities, and the sensitivity of those margins with respect to assumptions, system parameters, operating policy, and transactions. Security margins to voltage collapse blackouts, oscillatory instability, generator limits, voltage constraints and line overloads are considered. The usefulness of computing the sensitivities of these margins with respect to interarea transfers, loading parameters, generator dispatch, transmission line parameters, and VAR support is established for networks as large as 1500 buses. The sensitivity formulas presented apply to a range of power system models. Conventional sensitivity formulas such as line distribution factors, outage distribution factors, participation factors and penalty factors are shown to be special cases of the general sensitivity formulas derived in this thesis. The sensitivity formulas readily accommodate sparse matrix techniques. Margin sensitivity methods are shown to work effectively for avoiding voltage collapse blackouts caused by either saddle node bifurcation of equilibria or immediate instability due to generator reactive power limits. Extremely fast contingency analysis for voltage collapse can be implemented with margin sensitivity based rankings. Interarea transfer can be limited by voltage limits, line limits, or voltage stability. The sensitivity formulas presented in this thesis apply to security margins defined by any limit criteria. A method to compute transfer margins by directly locating intermediate events reduces the total number of loadflow iterations required by each margin computation and provides sensitivity information at minimal additional cost. Estimates of the effect of simultaneous transfers on the transfer margins agree well with the exact computations for a network model derived from a portion of the U.S grid. The accuracy of the estimates over a useful range of conditions and the ease of obtaining the estimates suggest that the sensitivity computations will be of practical value.

  5. Anomalous scaling of stochastic processes and the Moses effect

    NASA Astrophysics Data System (ADS)

    Chen, Lijian; Bassler, Kevin E.; McCauley, Joseph L.; Gunaratne, Gemunu H.

    2017-04-01

    The state of a stochastic process evolving over a time t is typically assumed to lie on a normal distribution whose width scales like t1/2. However, processes in which the probability distribution is not normal and the scaling exponent differs from 1/2 are known. The search for possible origins of such "anomalous" scaling and approaches to quantify them are the motivations for the work reported here. In processes with stationary increments, where the stochastic process is time-independent, autocorrelations between increments and infinite variance of increments can cause anomalous scaling. These sources have been referred to as the Joseph effect and the Noah effect, respectively. If the increments are nonstationary, then scaling of increments with t can also lead to anomalous scaling, a mechanism we refer to as the Moses effect. Scaling exponents quantifying the three effects are defined and related to the Hurst exponent that characterizes the overall scaling of the stochastic process. Methods of time series analysis that enable accurate independent measurement of each exponent are presented. Simple stochastic processes are used to illustrate each effect. Intraday financial time series data are analyzed, revealing that their anomalous scaling is due only to the Moses effect. In the context of financial market data, we reiterate that the Joseph exponent, not the Hurst exponent, is the appropriate measure to test the efficient market hypothesis.

  6. Incremental online learning in high dimensions.

    PubMed

    Vijayakumar, Sethu; D'Souza, Aaron; Schaal, Stefan

    2005-12-01

    Locally weighted projection regression (LWPR) is a new algorithm for incremental nonlinear function approximation in high-dimensional spaces with redundant and irrelevant input dimensions. At its core, it employs nonparametric regression with locally linear models. In order to stay computationally efficient and numerically robust, each local model performs the regression analysis with a small number of univariate regressions in selected directions in input space in the spirit of partial least squares regression. We discuss when and how local learning techniques can successfully work in high-dimensional spaces and review the various techniques for local dimensionality reduction before finally deriving the LWPR algorithm. The properties of LWPR are that it (1) learns rapidly with second-order learning methods based on incremental training, (2) uses statistically sound stochastic leave-one-out cross validation for learning without the need to memorize training data, (3) adjusts its weighting kernels based on only local information in order to minimize the danger of negative interference of incremental learning, (4) has a computational complexity that is linear in the number of inputs, and (5) can deal with a large number of-possibly redundant-inputs, as shown in various empirical evaluations with up to 90 dimensional data sets. For a probabilistic interpretation, predictive variance and confidence intervals are derived. To our knowledge, LWPR is the first truly incremental spatially localized learning method that can successfully and efficiently operate in very high-dimensional spaces.

  7. Anomalous scaling of stochastic processes and the Moses effect.

    PubMed

    Chen, Lijian; Bassler, Kevin E; McCauley, Joseph L; Gunaratne, Gemunu H

    2017-04-01

    The state of a stochastic process evolving over a time t is typically assumed to lie on a normal distribution whose width scales like t^{1/2}. However, processes in which the probability distribution is not normal and the scaling exponent differs from 1/2 are known. The search for possible origins of such "anomalous" scaling and approaches to quantify them are the motivations for the work reported here. In processes with stationary increments, where the stochastic process is time-independent, autocorrelations between increments and infinite variance of increments can cause anomalous scaling. These sources have been referred to as the Joseph effect and the Noah effect, respectively. If the increments are nonstationary, then scaling of increments with t can also lead to anomalous scaling, a mechanism we refer to as the Moses effect. Scaling exponents quantifying the three effects are defined and related to the Hurst exponent that characterizes the overall scaling of the stochastic process. Methods of time series analysis that enable accurate independent measurement of each exponent are presented. Simple stochastic processes are used to illustrate each effect. Intraday financial time series data are analyzed, revealing that their anomalous scaling is due only to the Moses effect. In the context of financial market data, we reiterate that the Joseph exponent, not the Hurst exponent, is the appropriate measure to test the efficient market hypothesis.

  8. Red and processed meat consumption and the risk of lung cancer: a dose-response meta-analysis of 33 published studies

    PubMed Central

    Xue, Xiu-Juan; Gao, Qing; Qiao, Jian-Hong; Zhang, Jie; Xu, Cui-Ping; Liu, Ju

    2014-01-01

    This meta-analysis was to summarize the published studies about the association between red/processed meat consumption and the risk of lung cancer. 5 databases were systematically reviewed, and random-effect model was used to pool the study results and to assess dose-response relationships. Results shown that six cohort studies and twenty eight case-control studies were included in this meat-analysis. The pooled Risk Radios (RR) for total red meat and processed meat were 1.44 (95% CI, 1.29-1.61) and 1.23 (95% CI, 1.10-1.37), respectively. Dose-response analysis revealed that for every increment of 120 grams red meat per day the risk of lung cancer increases 35% and for every increment of 50 grams red meat per day the risk of lung cancer increases 20%. The present dose-response meta-analysis suggested that both red and processed meat consumption showed a positive effect on lung cancer risk. PMID:25035778

  9. Derivation of improved load transformation matrices for launchers-spacecraft coupled analysis, and direct computation of margins of safety

    NASA Technical Reports Server (NTRS)

    Klein, M.; Reynolds, J.; Ricks, E.

    1989-01-01

    Load and stress recovery from transient dynamic studies are improved upon using an extended acceleration vector in the modal acceleration technique applied to structural analysis. Extension of the normal LTM (load transformation matrices) stress recovery to automatically compute margins of safety is presented with an application to the Hubble space telescope.

  10. Composite marginal quantile regression analysis for longitudinal adolescent body mass index data.

    PubMed

    Yang, Chi-Chuan; Chen, Yi-Hau; Chang, Hsing-Yi

    2017-09-20

    Childhood and adolescenthood overweight or obesity, which may be quantified through the body mass index (BMI), is strongly associated with adult obesity and other health problems. Motivated by the child and adolescent behaviors in long-term evolution (CABLE) study, we are interested in individual, family, and school factors associated with marginal quantiles of longitudinal adolescent BMI values. We propose a new method for composite marginal quantile regression analysis for longitudinal outcome data, which performs marginal quantile regressions at multiple quantile levels simultaneously. The proposed method extends the quantile regression coefficient modeling method introduced by Frumento and Bottai (Biometrics 2016; 72:74-84) to longitudinal data accounting suitably for the correlation structure in longitudinal observations. A goodness-of-fit test for the proposed modeling is also developed. Simulation results show that the proposed method can be much more efficient than the analysis without taking correlation into account and the analysis performing separate quantile regressions at different quantile levels. The application to the longitudinal adolescent BMI data from the CABLE study demonstrates the practical utility of our proposal. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  11. A triangular thin shell finite element: Nonlinear analysis. [structural analysis

    NASA Technical Reports Server (NTRS)

    Thomas, G. R.; Gallagher, R. H.

    1975-01-01

    Aspects of the formulation of a triangular thin shell finite element which pertain to geometrically nonlinear (small strain, finite displacement) behavior are described. The procedure for solution of the resulting nonlinear algebraic equations combines a one-step incremental (tangent stiffness) approach with one iteration in the Newton-Raphson mode. A method is presented which permits a rational estimation of step size in this procedure. Limit points are calculated by means of a superposition scheme coupled to the incremental side of the solution procedure while bifurcation points are calculated through a process of interpolation of the determinants of the tangent-stiffness matrix. Numerical results are obtained for a flat plate and two curved shell problems and are compared with alternative solutions.

  12. Electricity prices in a competitive environment: Marginal cost pricing of generation services and financial status of electric utilities. A preliminary analysis through 2015

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

    NONE

    1997-08-01

    The emergence of competitive markets for electricity generation services is changing the way that electricity is and will be priced in the United States. This report presents the results of an analysis that focuses on two questions: (1) How are prices for competitive generation services likely to differ from regulated prices if competitive prices are based on marginal costs rather than regulated {open_quotes}cost-of-service{close_quotes} pricing? (2) What impacts will the competitive pricing of generation services (based on marginal costs) have on electricity consumption patterns, production costs, and the financial integrity patterns, production costs, and the financial integrity of electricity suppliers? Thismore » study is not intended to be a cost-benefit analysis of wholesale or retail competition, nor does this report include an analysis of the macroeconomic impacts of competitive electricity prices.« less

  13. Comparison of a Traditional Probabilistic Risk Assessment Approach with Advanced Safety Analysis

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

    Smith, Curtis L; Mandelli, Diego; Zhegang Ma

    2014-11-01

    As part of the Light Water Sustainability Program (LWRS) [1], the purpose of the Risk Informed Safety Margin Characterization (RISMC) [2] Pathway research and development (R&D) is to support plant decisions for risk-informed margin management with the aim to improve economics, reliability, and sustain safety of current NPPs. In this paper, we describe the RISMC analysis process illustrating how mechanistic and probabilistic approaches are combined in order to estimate a safety margin. We use the scenario of a “station blackout” (SBO) wherein offsite power and onsite power is lost, thereby causing a challenge to plant safety systems. We describe themore » RISMC approach, illustrate the station blackout modeling, and contrast this with traditional risk analysis modeling for this type of accident scenario. We also describe our approach we are using to represent advanced flooding analysis.« less

  14. Serological testing versus other strategies for diagnosis of active tuberculosis in India: a cost-effectiveness analysis.

    PubMed

    Dowdy, David W; Steingart, Karen R; Pai, Madhukar

    2011-08-01

    Undiagnosed and misdiagnosed tuberculosis (TB) drives the epidemic in India. Serological (antibody detection) TB tests are not recommended by any agency, but widely used in many countries, including the Indian private sector. The cost and impact of using serology compared with other diagnostic techniques is unknown. Taking a patient cohort conservatively equal to the annual number of serological tests done in India (1.5 million adults suspected of having active TB), we used decision analysis to estimate costs and effectiveness of sputum smear microscopy (US$3.62 for two smears), microscopy plus automated liquid culture (mycobacterium growth indicator tube [MGIT], US$20/test), and serological testing (anda-tb ELISA, US$20/test). Data on test accuracy and costs were obtained from published literature. We adopted the perspective of the Indian TB control sector and an analysis frame of 1 year. Our primary outcome was the incremental cost per disability-adjusted life year (DALY) averted. We performed one-way sensitivity analysis on all model parameters, with multiway sensitivity analysis on variables to which the model was most sensitive. If used instead of sputum microscopy, serology generated an estimated 14,000 more TB diagnoses, but also 121,000 more false-positive diagnoses, 102,000 fewer DALYs averted, and 32,000 more secondary TB cases than microscopy, at approximately four times the incremental cost (US$47.5 million versus US$11.9 million). When added to high-quality sputum smears, MGIT culture was estimated to avert 130,000 incremental DALYs at an incremental cost of US$213 per DALY averted. Serology was dominated by (i.e., more costly and less effective than) MGIT culture and remained less economically favorable than sputum smear or TB culture in one-way and multiway sensitivity analyses. In India, sputum smear microscopy remains the most cost-effective diagnostic test available for active TB; efforts to increase access to quality-assured microscopy should take priority. In areas where high-quality microscopy exists and resources are sufficient, MGIT culture is more cost-effective than serology as an additional diagnostic test for TB. These data informed a recently published World Health Organization policy statement against serological tests.

  15. Machine-learning-based calving prediction from activity, lying, and ruminating behaviors in dairy cattle.

    PubMed

    Borchers, M R; Chang, Y M; Proudfoot, K L; Wadsworth, B A; Stone, A E; Bewley, J M

    2017-07-01

    The objective of this study was to use automated activity, lying, and rumination monitors to characterize prepartum behavior and predict calving in dairy cattle. Data were collected from 20 primiparous and 33 multiparous Holstein dairy cattle from September 2011 to May 2013 at the University of Kentucky Coldstream Dairy. The HR Tag (SCR Engineers Ltd., Netanya, Israel) automatically collected neck activity and rumination data in 2-h increments. The IceQube (IceRobotics Ltd., South Queensferry, United Kingdom) automatically collected number of steps, lying time, standing time, number of transitions from standing to lying (lying bouts), and total motion, summed in 15-min increments. IceQube data were summed in 2-h increments to match HR Tag data. All behavioral data were collected for 14 d before the predicted calving date. Retrospective data analysis was performed using mixed linear models to examine behavioral changes by day in the 14 d before calving. Bihourly behavioral differences from baseline values over the 14 d before calving were also evaluated using mixed linear models. Changes in daily rumination time, total motion, lying time, and lying bouts occurred in the 14 d before calving. In the bihourly analysis, extreme values for all behaviors occurred in the final 24 h, indicating that the monitored behaviors may be useful in calving prediction. To determine whether technologies were useful at predicting calving, random forest, linear discriminant analysis, and neural network machine-learning techniques were constructed and implemented using R version 3.1.0 (R Foundation for Statistical Computing, Vienna, Austria). These methods were used on variables from each technology and all combined variables from both technologies. A neural network analysis that combined variables from both technologies at the daily level yielded 100.0% sensitivity and 86.8% specificity. A neural network analysis that combined variables from both technologies in bihourly increments was used to identify 2-h periods in the 8 h before calving with 82.8% sensitivity and 80.4% specificity. Changes in behavior and machine-learning alerts indicate that commercially marketed behavioral monitors may have calving prediction potential. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  16. Online and unsupervised face recognition for continuous video stream

    NASA Astrophysics Data System (ADS)

    Huo, Hongwen; Feng, Jufu

    2009-10-01

    We present a novel online face recognition approach for video stream in this paper. Our method includes two stages: pre-training and online training. In the pre-training phase, our method observes interactions, collects batches of input data, and attempts to estimate their distributions (Box-Cox transformation is adopted here to normalize rough estimates). In the online training phase, our method incrementally improves classifiers' knowledge of the face space and updates it continuously with incremental eigenspace analysis. The performance achieved by our method shows its great potential in video stream processing.

  17. Electricity Prices in a Competitive Environment: Marginal Cost Pricing

    EIA Publications

    1997-01-01

    Presents the results of an analysis that focuses on two questions: (1) How are prices for competitive generation services likely to differ from regulated prices if competitive prices are based on marginal costs rather than regulated cost-of-service pricing? (2) What impacts will the competitive pricing of generation services (based on marginal costs) have on electricity consumption patterns, production costs, and the financial integrity of electricity suppliers?

  18. Comparative Evaluation of Marginal Adaptation of BiodentineTM and Other Commonly Used Root End Filling Materials-An Invitro Study

    PubMed Central

    P.V., Ravichandra; Vemisetty, Harikumar; K., Deepthi; Reddy S, Jayaprada; D., Ramkiran; Krishna M., Jaya Nagendra; Malathi, Gita

    2014-01-01

    Aim: The purpose of this investigation was to evaluate the marginal adaptation of three root-end filling materials Glass ionomer cement, Mineral trioxide aggregate and BiodentineTM. Methodology: Thirty human single-rooted teeth were resected 3 mm from the apex. Root-end cavities were then prepared using an ultrasonic tip and filled with one of the following materials Glass ionomer cement (GIC), Mineral trioxide aggregate (MTA) and a bioactive cement BiodentineTM. The apical portions of the roots were then sectioned to obtain three 1 mm thick transversal sections. Confocal laser scanning microscopy (CLSM) was used to determine area of gaps and adaptation of the root-end filling materials with the dentin. The Post hoc test, a multiple comparison test was used for statistical data analysis. Results: Statistical analysis showed lowest marginal gaps (11143.42±967.753m2) and good marginal adaptation with BiodentineTM followed by MTA (22300.97±3068.883m2) and highest marginal gaps with GIC (33388.17±12155.903m2) which were statistically significant (p<0.0001). Conclusion: A new root end filling material BiodentineTM showed better marginal adaptation than commonly used root end filling materials PMID:24783148

  19. Marginal and Random Intercepts Models for Longitudinal Binary Data With Examples From Criminology.

    PubMed

    Long, Jeffrey D; Loeber, Rolf; Farrington, David P

    2009-01-01

    Two models for the analysis of longitudinal binary data are discussed: the marginal model and the random intercepts model. In contrast to the linear mixed model (LMM), the two models for binary data are not subsumed under a single hierarchical model. The marginal model provides group-level information whereas the random intercepts model provides individual-level information including information about heterogeneity of growth. It is shown how a type of numerical averaging can be used with the random intercepts model to obtain group-level information, thus approximating individual and marginal aspects of the LMM. The types of inferences associated with each model are illustrated with longitudinal criminal offending data based on N = 506 males followed over a 22-year period. Violent offending indexed by official records and self-report were analyzed, with the marginal model estimated using generalized estimating equations and the random intercepts model estimated using maximum likelihood. The results show that the numerical averaging based on the random intercepts can produce prediction curves almost identical to those obtained directly from the marginal model parameter estimates. The results provide a basis for contrasting the models and the estimation procedures and key features are discussed to aid in selecting a method for empirical analysis.

  20. Oral administration of kefiran exerts a bifidogenic effect on BALB/c mice intestinal microbiota.

    PubMed

    Hamet, M F; Medrano, M; Pérez, P F; Abraham, A G

    2016-01-01

    The activity of kefiran, the exopolysaccharide present in kefir grains, was evaluated on intestinal bacterial populations in BALB/c mice. Animals were orally administered with kefiran and Eubacteria, lactobacilli and bifidobacteria populations were monitored in faeces of mice at days 0, 2, 7, 14 and 21. Profiles obtained by Denaturing Gradient Gel Electrophoresis (DGGE) with primers for Eubacteria were compared by principal component analysis and clearly defined clusters, correlating with the time of kefiran consumption, were obtained. Furthermore, profile analysis of PCR products amplified with specific oligonucleotides for bifidobacteria showed an increment in the number of DGGE bands in the groups administered with kefiran. Fluorescent In Situ Hybridisation (FISH) with specific probes for bifidobacteria showed an increment of this population in faeces, in accordance to DGGE results. The bifidobacteria population was also studied on distal colon content after 0, 2 and 7 days of kefiran administration. Analysis of PCR products by DGGE with Eubacteria primers showed an increment in the number and intensity of bands with high GC content of mice administered with kefiran. Sequencing of DGGE bands confirmed that bifidobacteria were one of the bacterial populations modified by kefiran administration. DGGE profiles of PCR amplicons obtained by using Bifidobacterium or Lactobacillus specific primers confirmed that kefiran administration enhances bifidobacteria, however no changes were observed in Lactobacillus populations. The results of the analysis of bifidobacteria populations assessed on different sampling sites in a murine model support the use of this exopolysaccharide as a bifidogenic functional ingredient.

  1. Risk factors for mortality in patients undergoing hemodialysis: A systematic review and meta-analysis.

    PubMed

    Ma, Lijie; Zhao, Sumei

    2017-07-01

    No consensus exists regarding the factors influencing mortality in patients undergoing hemodialysis (HD). This meta-analysis aimed to evaluate the impact of various patient characteristics on the risk of mortality in such patients. PubMed, Embase, and Cochrane Central were searched for studies evaluating the risk factors for mortality in patients undergoing HD. The factors included age, gender, diabetes mellitus (DM), body mass index (BMI), previous cardiovascular disease (CVD), HD duration, hemoglobin, albumin, white blood cell, C-reactive protein (CRP), parathyroid hormone, total iron binding capacity (TIBC), iron, ln ferritin, adiponectin, apolipoprotein A1 (ApoA1), ApoA2, ApoA3, high-density lipoprotein (HDL), total cholesterol, hemoglobin A1c (HbA1c), serum phosphate, troponin T (TnT), and B-type natriuretic peptide (BNP). Relative risks with 95% confidence intervals were derived. Data were synthesized using the random-effects model. Age (per 1-year increment), DM, previous CVD, CRP (higher versus lower), ln ferritin, adiponectin (per 10.0μg/mL increment), HbA1c (higher versus lower), TnT, and BNP were associated with an increased risk of all-cause mortality. BMI (per 1kg/m 2 increment), hemoglobin (per 1d/dL increment), albumin (higher versus lower), TIBC, iron, ApoA2, and ApoA3 were associated with reduced risk of all-cause mortality. Age (per 1-year increment), gender (women versus men), DM, previous CVD, HD duration, ln ferritin, HDL, and HbA1c (higher versus lower) significantly increased the risk of cardiac death. Albumin (higher versus lower), TIBC, and ApoA2 had a beneficial impact on the risk of cardiac death. Multiple markers and factors influence the risk of mortality and cardiac death in patients undergoing HD. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Cross-correlation of instantaneous phase increments in pressure-flow fluctuations: Applications to cerebral autoregulation

    NASA Astrophysics Data System (ADS)

    Chen, Zhi; Hu, Kun; Stanley, H. Eugene; Novak, Vera; Ivanov, Plamen Ch.

    2006-03-01

    We investigate the relationship between the blood flow velocities (BFV) in the middle cerebral arteries and beat-to-beat blood pressure (BP) recorded from a finger in healthy and post-stroke subjects during the quasisteady state after perturbation for four different physiologic conditions: supine rest, head-up tilt, hyperventilation, and CO2 rebreathing in upright position. To evaluate whether instantaneous BP changes in the steady state are coupled with instantaneous changes in the BFV, we compare dynamical patterns in the instantaneous phases of these signals, obtained from the Hilbert transform, as a function of time. We find that in post-stroke subjects the instantaneous phase increments of BP and BFV exhibit well-pronounced patterns that remain stable in time for all four physiologic conditions, while in healthy subjects these patterns are different, less pronounced, and more variable. We propose an approach based on the cross-correlation of the instantaneous phase increments to quantify the coupling between BP and BFV signals. We find that the maximum correlation strength is different for the two groups and for the different conditions. For healthy subjects the amplitude of the cross-correlation between the instantaneous phase increments of BP and BFV is small and attenuates within 3-5 heartbeats. In contrast, for post-stroke subjects, this amplitude is significantly larger and cross-correlations persist up to 20 heartbeats. Further, we show that the instantaneous phase increments of BP and BFV are cross-correlated even within a single heartbeat cycle. We compare the results of our approach with three complementary methods: direct BP-BFV cross-correlation, transfer function analysis, and phase synchronization analysis. Our findings provide insight into the mechanism of cerebral vascular control in healthy subjects, suggesting that this control mechanism may involve rapid adjustments (within a heartbeat) of the cerebral vessels, so that BFV remains steady in response to changes in peripheral BP.

  3. Cross-correlation of instantaneous phase increments in pressure-flow fluctuations: applications to cerebral autoregulation.

    PubMed

    Chen, Zhi; Hu, Kun; Stanley, H Eugene; Novak, Vera; Ivanov, Plamen Ch

    2006-03-01

    We investigate the relationship between the blood flow velocities (BFV) in the middle cerebral arteries and beat-to-beat blood pressure (BP) recorded from a finger in healthy and post-stroke subjects during the quasisteady state after perturbation for four different physiologic conditions: supine rest, head-up tilt, hyperventilation, and CO2 rebreathing in upright position. To evaluate whether instantaneous BP changes in the steady state are coupled with instantaneous changes in the BFV, we compare dynamical patterns in the instantaneous phases of these signals, obtained from the Hilbert transform, as a function of time. We find that in post-stroke subjects the instantaneous phase increments of BP and BFV exhibit well-pronounced patterns that remain stable in time for all four physiologic conditions, while in healthy subjects these patterns are different, less pronounced, and more variable. We propose an approach based on the cross-correlation of the instantaneous phase increments to quantify the coupling between BP and BFV signals. We find that the maximum correlation strength is different for the two groups and for the different conditions. For healthy subjects the amplitude of the cross-correlation between the instantaneous phase increments of BP and BFV is small and attenuates within 3-5 heartbeats. In contrast, for post-stroke subjects, this amplitude is significantly larger and cross-correlations persist up to 20 heartbeats. Further, we show that the instantaneous phase increments of BP and BFV are cross-correlated even within a single heartbeat cycle. We compare the results of our approach with three complementary methods: direct BP-BFV cross-correlation, transfer function analysis, and phase synchronization analysis. Our findings provide insight into the mechanism of cerebral vascular control in healthy subjects, suggesting that this control mechanism may involve rapid adjustments (within a heartbeat) of the cerebral vessels, so that BFV remains steady in response to changes in peripheral BP.

  4. International Space Station Increment-2 Microgravity Environment Summary Report

    NASA Technical Reports Server (NTRS)

    Jules, Kenol; Hrovat, Kenneth; Kelly, Eric; McPherson, Kevin; Reckart, Timothy

    2002-01-01

    This summary report presents the results of some of the processed acceleration data, collected aboard the International Space Station during the period of May to August 2001, the Increment-2 phase of the station. Two accelerometer systems were used to measure the acceleration levels during activities that took place during the Increment-2 segment. However, not all of the activities were analyzed for this report due to time constraints, lack of precise information regarding some payload operations and other station activities. The National Aeronautics and Space Administration sponsors the Microgravity Acceleration Measurement System and the Space Acceleration Microgravity System to support microgravity science experiments, which require microgravity acceleration measurements. On April 19, 2001, both the Microgravity Acceleration Measurement System and the Space Acceleration Measurement System units were launched on STS-100 from the Kennedy Space Center for installation on the International Space Station. The Microgravity Acceleration Measurement System unit was flown to the station in support of science experiments requiring quasi-steady acceleration measurements, while the Space Acceleration Measurement System unit was flown to support experiments requiring vibratory acceleration measurement. Both acceleration systems are also used in support of vehicle microgravity requirements verification. The International Space Station Increment-2 reduced gravity environment analysis presented in this report uses acceleration data collected by both sets of accelerometer systems: 1) The Microgravity Acceleration Measurement System, which consists of two sensors: the Orbital Acceleration Research Experiment Sensor Subsystem, a low frequency range sensor (up to 1 Hz), is used to characterize the quasi-steady environment for payloads and the vehicle, and the High Resolution Accelerometer Package, which is used to characterize the vibratory environment up to 100 Hz. 2) The Space Acceleration Measurement System, which is a high frequency sensor, measures vibratory acceleration data in the range of 0.01 to 300 Hz. This summary report presents analysis of some selected quasisteady and vibratory activities measured by these accelerometers during Increment-2 from May to August 20, 2001.

  5. A unifying framework for marginalized random intercept models of correlated binary outcomes

    PubMed Central

    Swihart, Bruce J.; Caffo, Brian S.; Crainiceanu, Ciprian M.

    2013-01-01

    We demonstrate that many current approaches for marginal modeling of correlated binary outcomes produce likelihoods that are equivalent to the copula-based models herein. These general copula models of underlying latent threshold random variables yield likelihood-based models for marginal fixed effects estimation and interpretation in the analysis of correlated binary data with exchangeable correlation structures. Moreover, we propose a nomenclature and set of model relationships that substantially elucidates the complex area of marginalized random intercept models for binary data. A diverse collection of didactic mathematical and numerical examples are given to illustrate concepts. PMID:25342871

  6. A maximal incremental effort alters tear osmolarity depending on the fitness level in military helicopter pilots.

    PubMed

    Vera, Jesús; Jiménez, Raimundo; Madinabeitia, Iker; Masiulis, Nerijus; Cárdenas, David

    2017-10-01

    Fitness level modulates the physiological responses to exercise for a variety of indices. While intense bouts of exercise have been demonstrated to increase tear osmolarity (Tosm), it is not known if fitness level can affect the Tosm response to acute exercise. This study aims to compare the effect of a maximal incremental test on Tosm between trained and untrained military helicopter pilots. Nineteen military helicopter pilots (ten trained and nine untrained) performed a maximal incremental test on a treadmill. A tear sample was collected before and after physical effort to determine the exercise-induced changes on Tosm. The Bayesian statistical analysis demonstrated that Tosm significantly increased from 303.72 ± 6.76 to 310.56 ± 8.80 mmol/L after performance of a maximal incremental test. However, while the untrained group showed an acute Tosm rise (12.33 mmol/L of increment), the trained group experienced a stable Tosm physical effort (1.45 mmol/L). There was a significant positive linear association between fat indices and Tosm changes (correlation coefficients [r] range: 0.77-0.89), whereas the Tosm changes displayed a negative relationship with the cardiorespiratory capacity (VO2 max; r = -0.75) and performance parameters (r = -0.75 for velocity, and r = -0.67 for time to exhaustion). The findings from this study provide evidence that fitness level is a major determinant of Tosm response to maximal incremental physical effort, showing a fairly linear association with several indices related to fitness level. High fitness level seems to be beneficial to avoid Tosm changes as consequence of intense exercise. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Response of a Circular Tunnel Through Rock to a Harmonic Rayleigh Wave

    NASA Astrophysics Data System (ADS)

    Kung, Chien-Lun; Wang, Tai-Tien; Chen, Cheng-Hsun; Huang, Tsan-Hwei

    2018-02-01

    A factor that combines tunnel depth and incident wavelength has been numerically determined to dominate the seismic responses of a tunnel in rocks that are subjected to harmonic P- and S-waves. This study applies the dynamic finite element method to investigate the seismic response of shallow overburden tunnels. Seismically induced stress increments in the lining of a circular tunnel that is subjected to an incident harmonic R-wave are examined. The determination of R-wave considers the dominant frequency of acceleration history of the 1999 Chi-Chi earthquake measured near the site with damage to two case tunnels at specifically shallow depth. An analysis reveals that the normalized seismically induced axial, shear and flexural stress increments in the lining of a tunnel reach their respective peaks at the depth h/ λ = 0.15, where the ground motion that is generated by an incident of R-wave has its maximum. The tunnel radius has a stronger effect on seismically induced stress increments than does tunnel depth. A greater tunnel radius yields higher normalized seismically induced axial stress increments and lower normalized seismically induced shear and flexural stress increments. The inertia of the thin overburden layer above the tunnel impedes the propagation of the wave and affects the motion of the ground around the tunnel. With an extremely shallow overburden, such an effect can change the envelope of the normalized seismically induced stress increments from one with a symmetric four-petal pattern into one with a non-symmetric three-petal pattern. The simulated results may partially elucidate the spatial distributions of cracks that were observed in the lining of the case tunnels.

  8. Experimental and numerical study on optimization of the single point incremental forming of AINSI 304L stainless steel sheet

    NASA Astrophysics Data System (ADS)

    Saidi, B.; Giraud-Moreau, L.; Cherouat, A.; Nasri, R.

    2017-09-01

    AINSI 304L stainless steel sheets are commonly formed into a variety of shapes for applications in the industrial, architectural, transportation and automobile fields, it’s also used for manufacturing of denture base. In the field of dentistry, there is a need for personalized devises that are custom made for the patient. The single point incremental forming process is highly promising in this area for manufacturing of denture base. The single point incremental forming process (ISF) is an emerging process based on the use of a spherical tool, which is moved along CNC controlled tool path. One of the major advantages of this process is the ability to program several punch trajectories on the same machine in order to obtain different shapes. Several applications of this process exist in the medical field for the manufacturing of personalized titanium prosthesis (cranial plate, knee prosthesis...) due to the need of product customization to each patient. The objective of this paper is to study the incremental forming of AISI 304L stainless steel sheets for future applications in the dentistry field. During the incremental forming process, considerable forces can occur. The control of the forming force is particularly important to ensure the safe use of the CNC milling machine and preserve the tooling and machinery. In this paper, the effect of four different process parameters on the maximum force is studied. The proposed approach consists in using an experimental design based on experimental results. An analysis of variance was conducted with ANOVA to find the input parameters allowing to minimize the maximum forming force. A numerical simulation of the incremental forming process is performed with the optimal input process parameters. Numerical results are compared with the experimental ones.

  9. Regulatory Impact Analysis (RIA) for the Proposed Revisions to the Sulfur Dioxide National Ambient Air Quality Standards (NAAQS)

    EPA Pesticide Factsheets

    This Regulatory Impact Analysis (RIA) provides estimates of the incremental costs and monetized human health benefits of attaining a revised short‐term Sulfur Dioxide (SO2) NAAQS within the current monitoring network.

  10. Multimodal optical analysis discriminates freshly extracted human sample of gliomas, metastases and meningiomas from their appropriate controls

    NASA Astrophysics Data System (ADS)

    Zanello, Marc; Poulon, Fanny; Pallud, Johan; Varlet, Pascale; Hamzeh, H.; Abi Lahoud, Georges; Andreiuolo, Felipe; Ibrahim, Ali; Pages, Mélanie; Chretien, Fabrice; di Rocco, Federico; Dezamis, Edouard; Nataf, François; Turak, Baris; Devaux, Bertrand; Abi Haidar, Darine

    2017-02-01

    Delineating tumor margins as accurately as possible is of primordial importance in surgical oncology: extent of resection is associated with survival but respect of healthy surrounding tissue is necessary for preserved quality of life. The real-time analysis of the endogeneous fluorescence signal of brain tissues is a promising tool for defining margins of brain tumors. The present study aims to demonstrate the feasibility of multimodal optical analysis to discriminate fresh samples of gliomas, metastases and meningiomas from their appropriate controls. Tumor samples were studied on an optical fibered endoscope using spectral and fluorescence lifetime analysis and then on a multimodal set-up for acquiring spectral, one and two-photon fluorescence images, second harmonic generation signals and two-photon fluorescence lifetime datasets. The obtained data allowed us to differentiate healthy samples from tumor samples. These results confirmed the possible clinical relevance of this real-time multimodal optical analysis. This technique can be easily applied to neurosurgical procedures for a better delineation of surgical margins.

  11. Money well spent: a comparison of hospital operating margin for laparoscopic and open colectomies.

    PubMed

    Koopmann, M C; Harms, B A; Heise, C P

    2007-10-01

    Cost analysis after laparoscopic colectomy has been examined, although reports evaluating the effects of laparoscopy on hospital operating margin are lacking. We compared several cost/revenue measures, including hospital operating margin, between open and laparoscopic colectomies at an academic center. Our cost-accounting database was queried for laparoscopic partial (LPC) and total colectomies (LTC), and open partial (OPC) and total colectomies (OTC) to analyze net revenue, total costs, and total hospital operating margin over a 4-year period. Laparoscopic and open colectomy cases were compared, with mean operating margin as the primary outcome. From July, 2002 through May, 2006, 842 patients were included for analysis with 138 undergoing laparoscopic colectomy. Net revenue was higher in the LTC group compared with open (US dollars 30,300 vs US dollars 26,800 [P = .02]), and lower in the LPC group (US dollars 15,300 vs US dollars 21,300 open [P < .0001]). Total costs were reduced in both the LPC and LTC groups compared with open [US dollars 11,700 vs US dollars 17,600 [P < .0001] and US dollars 18,000 vs US dollars 19,400 [P = .0019], respectively). LPC resulted in a similar HOM (US dollars 3,602) compared with OPC (US dollars 3,647; P = .35). LTC resulted in a higher HOM (US dollars 12,300) compared with OTC (US dollars 7,400; P = .02). LTC generates a significantly higher hospital operating margin than an OTC, although the margins are similar for LPC and OPC.

  12. Matching the Statistical Model to the Research Question for Dental Caries Indices with Many Zero Counts.

    PubMed

    Preisser, John S; Long, D Leann; Stamm, John W

    2017-01-01

    Marginalized zero-inflated count regression models have recently been introduced for the statistical analysis of dental caries indices and other zero-inflated count data as alternatives to traditional zero-inflated and hurdle models. Unlike the standard approaches, the marginalized models directly estimate overall exposure or treatment effects by relating covariates to the marginal mean count. This article discusses model interpretation and model class choice according to the research question being addressed in caries research. Two data sets, one consisting of fictional dmft counts in 2 groups and the other on DMFS among schoolchildren from a randomized clinical trial comparing 3 toothpaste formulations to prevent incident dental caries, are analyzed with negative binomial hurdle, zero-inflated negative binomial, and marginalized zero-inflated negative binomial models. In the first example, estimates of treatment effects vary according to the type of incidence rate ratio (IRR) estimated by the model. Estimates of IRRs in the analysis of the randomized clinical trial were similar despite their distinctive interpretations. The choice of statistical model class should match the study's purpose, while accounting for the broad decline in children's caries experience, such that dmft and DMFS indices more frequently generate zero counts. Marginalized (marginal mean) models for zero-inflated count data should be considered for direct assessment of exposure effects on the marginal mean dental caries count in the presence of high frequencies of zero counts. © 2017 S. Karger AG, Basel.

  13. Matching the Statistical Model to the Research Question for Dental Caries Indices with Many Zero Counts

    PubMed Central

    Preisser, John S.; Long, D. Leann; Stamm, John W.

    2017-01-01

    Marginalized zero-inflated count regression models have recently been introduced for the statistical analysis of dental caries indices and other zero-inflated count data as alternatives to traditional zero-inflated and hurdle models. Unlike the standard approaches, the marginalized models directly estimate overall exposure or treatment effects by relating covariates to the marginal mean count. This article discusses model interpretation and model class choice according to the research question being addressed in caries research. Two datasets, one consisting of fictional dmft counts in two groups and the other on DMFS among schoolchildren from a randomized clinical trial (RCT) comparing three toothpaste formulations to prevent incident dental caries, are analysed with negative binomial hurdle (NBH), zero-inflated negative binomial (ZINB), and marginalized zero-inflated negative binomial (MZINB) models. In the first example, estimates of treatment effects vary according to the type of incidence rate ratio (IRR) estimated by the model. Estimates of IRRs in the analysis of the RCT were similar despite their distinctive interpretations. Choice of statistical model class should match the study’s purpose, while accounting for the broad decline in children’s caries experience, such that dmft and DMFS indices more frequently generate zero counts. Marginalized (marginal mean) models for zero-inflated count data should be considered for direct assessment of exposure effects on the marginal mean dental caries count in the presence of high frequencies of zero counts. PMID:28291962

  14. Texas curve margin of safety.

    DOT National Transportation Integrated Search

    2013-01-01

    This software can be used to assist with the assessment of margin of safety for a horizontal curve. It is intended for use by engineers and technicians responsible for safety analysis or management of rural highway pavement or traffic control devices...

  15. 77 FR 41109 - Margin Requirements for Uncleared Swaps for Swap Dealers and Major Swap Participants

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-12

    ... and specifically requests quantitative data and analysis on the comparative costs and benefits of the... quantitative impact study (``QIS'') to assess the costs and benefits of margin requirements. The results of the...

  16. Cost-effectiveness analysis of two treatment strategies for chronic hepatitis C before and after access to direct-acting antivirals in Spain.

    PubMed

    Turnes, Juan; Domínguez-Hernández, Raquel; Casado, Miguel Ángel

    To evaluate the cost-effectiveness of a strategy based on direct-acting antivirals (DAAs) following the marketing of simeprevir and sofosbuvir (post-DAA) versus a pre-direct-acting antiviral strategy (pre-DAA) in patients with chronic hepatitis C, from the perspective of the Spanish National Health System. A decision tree combined with a Markov model was used to estimate the direct health costs (€, 2016) and health outcomes (quality-adjusted life years, QALYs) throughout the patient's life, with an annual discount rate of 3%. The sustained virological response, percentage of patients treated or not treated in each strategy, clinical characteristics of the patients, annual likelihood of transition, costs of treating and managing the disease, and utilities were obtained from the literature. The cost-effectiveness analysis was expressed as an incremental cost-effectiveness ratio (incremental cost per QALY gained). A deterministic sensitivity analysis and a probabilistic sensitivity analysis were performed. The post-DAA strategy showed higher health costs per patient (€30,944 vs. €23,707) than the pre-DAA strategy. However, it was associated with an increase of QALYs gained (15.79 vs. 12.83), showing an incremental cost-effectiveness ratio of €2,439 per QALY. The deterministic sensitivity analysis and the probabilistic sensitivity analysis showed the robustness of the results, with the post-DAA strategy being cost-effective in 99% of cases compared to the pre-DAA strategy. Compared to the pre-DAA strategy, the post-DAA strategy is efficient for the treatment of chronic hepatitis C in Spain, resulting in a much lower cost per QALY than the efficiency threshold used in Spain (€30,000 per QALY). Copyright © 2017 Elsevier España, S.L.U., AEEH y AEG. All rights reserved.

  17. Performance analysis of ‘Perturb and Observe’ and ‘Incremental Conductance’ MPPT algorithms for PV system

    NASA Astrophysics Data System (ADS)

    Lodhi, Ehtisham; Lodhi, Zeeshan; Noman Shafqat, Rana; Chen, Fieda

    2017-07-01

    Photovoltaic (PV) system usually employed The Maximum power point tracking (MPPT) techniques for increasing its efficiency. The performance of the PV system perhaps boosts by controlling at its apex point of power, in this way maximal power can be given to load. The proficiency of a PV system usually depends upon irradiance, temperature and array architecture. PV array shows a non-linear style for V-I curve and maximal power point on V-P curve also varies with changing environmental conditions. MPPT methods grantees that a PV module is regulated at reference voltage and to produce entire usage of the maximal output power. This paper gives analysis between two widely employed Perturb and Observe (P&O) and Incremental Conductance (INC) MPPT techniques. Their performance is evaluated and compared through theoretical analysis and digital simulation on the basis of response time and efficiency under varying irradiance and temperature condition using Matlab/Simulink.

  18. On nonstationarity and antipersistency in global temperature series

    NASA Astrophysics Data System (ADS)

    KäRner, O.

    2002-10-01

    Statistical analysis is carried out for satellite-based global daily tropospheric and stratospheric temperature anomaly and solar irradiance data sets. Behavior of the series appears to be nonstationary with stationary daily increments. Estimating long-range dependence between the increments reveals a remarkable difference between the two temperature series. Global average tropospheric temperature anomaly behaves similarly to the solar irradiance anomaly. Their daily increments show antipersistency for scales longer than 2 months. The property points at a cumulative negative feedback in the Earth climate system governing the tropospheric variability during the last 22 years. The result emphasizes a dominating role of the solar irradiance variability in variations of the tropospheric temperature and gives no support to the theory of anthropogenic climate change. The global average stratospheric temperature anomaly proceeds like a 1-dim random walk at least up to 11 years, allowing good presentation by means of the autoregressive integrated moving average (ARIMA) models for monthly series.

  19. Thermal elastoplastic structural analysis of non-metallic thermal protection systems

    NASA Technical Reports Server (NTRS)

    Chung, T. J.; Yagawa, G.

    1972-01-01

    An incremental theory and numerical procedure to analyze a three-dimensional thermoelastoplastic structure subjected to high temperature, surface heat flux, and volume heat supply as well as mechanical loadings are presented. Heat conduction equations and equilibrium equations are derived by assuming a specific form of incremental free energy, entropy, stresses and heat flux together with the first and second laws of thermodynamics, von Mises yield criteria and Prandtl-Reuss flow rule. The finite element discretization using the linear isotropic three-dimensional element for the space domain and a difference operator corresponding to a linear variation of temperature within a small time increment for the time domain lead to systematic solutions of temperature distribution and displacement and stress fields. Various boundary conditions such as insulated surfaces and convection through uninsulated surface can be easily treated. To demonstrate effectiveness of the present formulation a number of example problems are presented.

  20. Structural and incremental validity of the Wechsler Adult Intelligence Scale-Fourth Edition with a clinical sample.

    PubMed

    Nelson, Jason M; Canivez, Gary L; Watkins, Marley W

    2013-06-01

    Structural and incremental validity of the Wechsler Adult Intelligence Scale-Fourth Edition (WAIS-IV; Wechsler, 2008a) was examined with a sample of 300 individuals referred for evaluation at a university-based clinic. Confirmatory factor analysis indicated that the WAIS-IV structure was best represented by 4 first-order factors as well as a general intelligence factor in a direct hierarchical model. The general intelligence factor accounted for the most common and total variance among the subtests. Incremental validity analyses indicated that the Full Scale IQ (FSIQ) generally accounted for medium to large portions of academic achievement variance. For all measures of academic achievement, the first-order factors combined accounted for significant achievement variance beyond that accounted for by the FSIQ, but individual factor index scores contributed trivial amounts of achievement variance. Implications for interpreting WAIS-IV results are discussed. (PsycINFO Database Record (c) 2013 APA, all rights reserved).

  1. The political contradictions of incremental innovation: lessons from pharmaceutical patent examination in Brazil.

    PubMed

    Shadlen, Kenneth C

    2011-01-01

    Neodevelopmental patent regimes aim to facilitate local actors’ access to knowledge and also encourage incremental innovations. The case of pharmaceutical patent examination in Brazil illustrates political contradictions between these objectives. Brazil’s patent law includes the Ministry of Health in the examination of pharmaceutical patent applications. Though widely celebrated as a health-oriented policy, the Brazilian experience has become fraught with tensions and subject to decreasing levels of both stability and enforcement. I show how one pillar of the neodevelopmental regime, the array of initiatives to encourage incremental innovations, has fostered the acquisition of innovative capabilities in the Brazilian pharmaceutical sector, and how these new capabilities have altered actors’ policy preferences and thus contributed to the erosion of the coalition in support of the other pillar of the neodevelopmental regime, the health-oriented approach to examining pharmaceutical patents. The analysis of capability-derived preference formation points to an endogenous process of coalitional change.

  2. CRITICAL THERMAL INCREMENTS FOR RHYTHMIC RESPIRATORY MOVEMENTS OF INSECTS

    PubMed Central

    Crozier, W. J.; Stier, T. B.

    1925-01-01

    The rhythm of abdominal respiratory movements in various insects, aquatic and terrestrial, is shown to possess critical increments 11,500± or 16,500± calories (Libellula, Dixippus, Anax). These are characteristic of processes involved in respiration, and definitely differ from the increment 12,200 calories which is found in a number of instances of (non-respiratory) rhythmic neuromuscular activities of insects and other arthropods. With grasshoppers (Melanoplus), normal or freshly decapitated, the critical increment is 7,900, again a value encountered in connection with some phenomena of gaseous exchange and agreeing well with the value obtained for CO2 output in Melanoplus. It is shown that by decapitation the temperature characteristic for abdominal rhythm, in Melanoplus, is changed to 16,500, then to 11,300—depending upon the time since decapitation; intermediate values do not appear. The frequency of the respiratory movements seems to be controlled by a metabolically distinct group of neurones. The bearing of these results upon the theory of functional analysis by means of temperature characteristics is discussed, and it is pointed out that a definite standpoint becomes available from which to attempt the specific control of vital processes. PMID:19872148

  3. CRITICAL THERMAL INCREMENTS FOR RHYTHMIC RESPIRATORY MOVEMENTS OF INSECTS.

    PubMed

    Crozier, W J; Stier, T B

    1925-01-20

    The rhythm of abdominal respiratory movements in various insects, aquatic and terrestrial, is shown to possess critical increments 11,500+/- or 16,500+/- calories (Libellula, Dixippus, Anax). These are characteristic of processes involved in respiration, and definitely differ from the increment 12,200 calories which is found in a number of instances of (non-respiratory) rhythmic neuromuscular activities of insects and other arthropods. With grasshoppers (Melanoplus), normal or freshly decapitated, the critical increment is 7,900, again a value encountered in connection with some phenomena of gaseous exchange and agreeing well with the value obtained for CO(2) output in Melanoplus. It is shown that by decapitation the temperature characteristic for abdominal rhythm, in Melanoplus, is changed to 16,500, then to 11,300-depending upon the time since decapitation; intermediate values do not appear. The frequency of the respiratory movements seems to be controlled by a metabolically distinct group of neurones. The bearing of these results upon the theory of functional analysis by means of temperature characteristics is discussed, and it is pointed out that a definite standpoint becomes available from which to attempt the specific control of vital processes.

  4. Variable diffusion in stock market fluctuations

    NASA Astrophysics Data System (ADS)

    Hua, Jia-Chen; Chen, Lijian; Falcon, Liberty; McCauley, Joseph L.; Gunaratne, Gemunu H.

    2015-02-01

    We analyze intraday fluctuations in several stock indices to investigate the underlying stochastic processes using techniques appropriate for processes with nonstationary increments. The five most actively traded stocks each contains two time intervals during the day where the variance of increments can be fit by power law scaling in time. The fluctuations in return within these intervals follow asymptotic bi-exponential distributions. The autocorrelation function for increments vanishes rapidly, but decays slowly for absolute and squared increments. Based on these results, we propose an intraday stochastic model with linear variable diffusion coefficient as a lowest order approximation to the real dynamics of financial markets, and to test the effects of time averaging techniques typically used for financial time series analysis. We find that our model replicates major stylized facts associated with empirical financial time series. We also find that ensemble averaging techniques can be used to identify the underlying dynamics correctly, whereas time averages fail in this task. Our work indicates that ensemble average approaches will yield new insight into the study of financial markets' dynamics. Our proposed model also provides new insight into the modeling of financial markets dynamics in microscopic time scales.

  5. Structured Case Analysis: Developing Critical Thinking Skills in a Marketing Case Course

    ERIC Educational Resources Information Center

    Klebba, Joanne M.; Hamilton, Janet G.

    2007-01-01

    Structured case analysis is a hybrid pedagogy that flexibly combines diverse instructional methods with comprehensive case analysis as a mechanism to develop critical thinking skills. An incremental learning framework is proposed that allows instructors to develop and monitor content-specific theory and the corresponding critical thinking skills.…

  6. Investigation of the nonlinear seismic behavior of knee braced frames using the incremental dynamic analysis method

    NASA Astrophysics Data System (ADS)

    Sheidaii, Mohammad Reza; TahamouliRoudsari, Mehrzad; Gordini, Mehrdad

    2016-06-01

    In knee braced frames, the braces are attached to the knee element rather than the intersection of beams and columns. This bracing system is widely used and preferred over the other commonly used systems for reasons such as having lateral stiffness while having adequate ductility, damage concentration on the second degree convenience of repairing and replacing of these elements after Earthquake. The lateral stiffness of this system is supplied by the bracing member and the ductility of the frame attached to the knee length is supplied through the bending or shear yield of the knee member. In this paper, the nonlinear seismic behavior of knee braced frame systems has been investigated using incremental dynamic analysis (IDA) and the effects of the number of stories in a building, length and the moment of inertia of the knee member on the seismic behavior, elastic stiffness, ductility and the probability of failure of these systems has been determined. In the incremental dynamic analysis, after plotting the IDA diagrams of the accelerograms, the collapse diagrams in the limit states are determined. These diagrams yield that for a constant knee length with reduced moment of inertia, the probability of collapse in limit states heightens and also for a constant knee moment of inertia with increasing length, the probability of collapse in limit states increases.

  7. Cost-effectiveness analysis of apatinib treatment for chemotherapy-refractory advanced gastric cancer.

    PubMed

    Chen, Hong-Dou; Zhou, Jing; Wen, Feng; Zhang, Peng-Fei; Zhou, Ke-Xun; Zheng, Han-Rui; Yang, Yu; Li, Qiu

    2017-02-01

    Apatinib, a third-line or later treatment for advanced gastric cancer (aGC), was shown to improve overall survival and progression-free survival (PFS) compared with placebo in the phase III trial. Given the modest benefit with high costs, we further evaluated the cost-effectiveness of apatinib for patients with chemotherapy-refractory aGC. A Markov model was developed to simulate the disease process of aGC (PFS, progressive disease, and death) and estimate the incremental cost-effectiveness ratio (ICER) of apatinib to placebo. The health outcomes and utility scores were derived from the phase III trial and previously published sources, respectively. Total costs were calculated from the perspective of the Chinese health-care payer. Sensitivity analysis was used to explore model uncertainties. Treatment with apatinib was estimated to provide an incremental 0.09 quality-adjusted life years (QALYs) at an incremental cost of $8113.86 compared with placebo, which resulted in an ICER of $90,154.00 per QALY. Sensitivity analysis showed that across the wide variation of parameters, the ICER exceeded the willingness-to-pay threshold of $23,700.00 per QALY which was three times the Gross Domestic Product per Capita in China. Apatinib is not a cost-effective option for patients with aGC who experienced failure of at least two lines chemotherapy in China. However, for its positive clinical value and subliminal demand, apatinib can provide a new therapeutic option.

  8. Effect of various putty-wash impression techniques on marginal fit of cast crowns.

    PubMed

    Nissan, Joseph; Rosner, Ofir; Bukhari, Mohammed Amin; Ghelfan, Oded; Pilo, Raphael

    2013-01-01

    Marginal fit is an important clinical factor that affects restoration longevity. The accuracy of three polyvinyl siloxane putty-wash impression techniques was compared by marginal fit assessment using the nondestructive method. A stainless steel master cast containing three abutments with three metal crowns matching the three preparations was used to make 45 impressions: group A = single-step technique (putty and wash impression materials used simultaneously), group B = two-step technique with a 2-mm relief (putty as a preliminary impression to create a 2-mm wash space followed by the wash stage), and group C = two-step technique with a polyethylene spacer (plastic spacer used with the putty impression followed by the wash stage). Accuracy was assessed using a toolmaker microscope to measure and compare the marginal gaps between each crown and finish line on the duplicated stone casts. Each abutment was further measured at the mesial, buccal, and distal aspects. One-way analysis of variance was used for statistical analysis. P values and Scheffe post hoc contrasts were calculated. Significance was determined at .05. One-way analysis of variance showed significant differences among the three impression techniques in all three abutments and at all three locations (P < .001). Group B yielded dies with minimal gaps compared to groups A and C. The two-step impression technique with 2-mm relief was the most accurate regarding the crucial clinical factor of marginal fit.

  9. Diagnostic reliability of the cervical vertebral maturation method and standing height in the identification of the mandibular growth spurt.

    PubMed

    Perinetti, Giuseppe; Contardo, Luca; Castaldo, Attilio; McNamara, James A; Franchi, Lorenzo

    2016-07-01

    To evaluate the capability of both cervical vertebral maturation (CVM) stages 3 and 4 (CS3-4 interval) and the peak in standing height to identify the mandibular growth spurt throughout diagnostic reliability analysis. A previous longitudinal data set derived from 24 untreated growing subjects (15 females and nine males,) detailed elsewhere were reanalyzed. Mandibular growth was defined as annual increments in Condylion (Co)-Gnathion (Gn) (total mandibular length) and Co-Gonion Intersection (Goi) (ramus height) and their arithmetic mean (mean mandibular growth [mMG]). Subsequently, individual annual increments in standing height, Co-Gn, Co-Goi, and mMG were arranged according to annual age intervals, with the first and last intervals defined as 7-8 years and 15-16 years, respectively. An analysis was performed to establish the diagnostic reliability of the CS3-4 interval or the peak in standing height in the identification of the maximum individual increments of each Co-Gn, Co-Goi, and mMG measurement at each annual age interval. CS3-4 and standing height peak show similar but variable accuracy across annual age intervals, registering values between 0.61 (standing height peak, Co-Gn) and 0.95 (standing height peak and CS3-4, mMG). Generally, satisfactory diagnostic reliability was seen when the mandibular growth spurt was identified on the basis of the Co-Goi and mMG increments. Both CVM interval CS3-4 and peak in standing height may be used in routine clinical practice to enhance efficiency of treatments requiring identification of the mandibular growth spurt.

  10. Cost effectiveness of an intensive blood glucose control policy in patients with type 2 diabetes: economic analysis alongside randomised controlled trial (UKPDS 41)

    PubMed Central

    Gray, Alastair; Raikou, Maria; McGuire, Alistair; Fenn, Paul; Stevens, Richard; Cull, Carole; Stratton, Irene; Adler, Amanda; Holman, Rury; Turner, Robert

    2000-01-01

    Objective To estimate the cost effectiveness of conventional versus intensive blood glucose control in patients with type 2 diabetes. Design Incremental cost effectiveness analysis alongside randomised controlled trial. Setting 23 UK hospital clinic based study centres. Participants 3867 patients with newly diagnosed type 2 diabetes (mean age 53 years). Interventions Conventional (primarily diet) glucose control policy versus intensive control policy with a sulphonylurea or insulin. Main outcome measures Incremental cost per event-free year gained within the trial period. Results Intensive glucose control increased trial treatment costs by £695 (95% confidence interval £555 to £836) per patient but reduced the cost of complications by £957 (£233 to £1681) compared with conventional management. If standard practice visit patterns were assumed rather than trial conditions, the incremental cost of intensive management was £478 (−£275 to £1232) per patient. The within trial event-free time gained in the intensive group was 0.60 (0.12 to 1.10) years and the lifetime gain 1.14 (0.69 to 1.61) years. The incremental cost per event-free year gained was £1166 (costs and effects discounted at 6% a year) and £563 (costs discounted at 6% a year and effects not discounted). Conclusions Intensive blood glucose control in patients with type 2 diabetes significantly increased treatment costs but substantially reduced the cost of complications and increased the time free of complications. PMID:10818026

  11. Histopathological Validation of the Surface-Intermediate-Base Margin Score for Standardized Reporting of Resection Technique during Nephron Sparing Surgery.

    PubMed

    Minervini, Andrea; Campi, Riccardo; Kutikov, Alexander; Montagnani, Ilaria; Sessa, Francesco; Serni, Sergio; Raspollini, Maria Rosaria; Carini, Marco

    2015-10-01

    The surface-intermediate-base margin score is a novel standardized reporting system of resection techniques during nephron sparing surgery. We validated the surgeon assessed surface-intermediate-base score with microscopic histopathological assessment of partial nephrectomy specimens. Between June and August 2014 data were prospectively collected from 40 consecutive patients undergoing nephron sparing surgery. The surface-intermediate-base score was assigned to all cases. The score specific areas were color coded with tissue margin ink and sectioned for histological evaluation of healthy renal margin thickness. Maximum, minimum and mean thickness of healthy renal margin for each score specific area grade (surface [S] = 0, S = 1 ; intermediate [I] or base [B] = 0, I or B = 1, I or B = 2) was reported. The Mann-Whitney U and Kruskal-Wallis tests were used to compare the thickness of healthy renal margin in S = 0 vs 1 and I or B = 0 vs 1 vs 2 grades, respectively. Maximum, minimum and mean thickness of healthy renal margin was significantly different among score specific area grades S = 0 vs 1, and I or B = 0 vs 1, 0 vs 2 and 1 vs 2 (p <0.001). The main limitations of the study are the low number of the I or B = 1 and I or B = 2 samples and the assumption that each microscopic slide reflects the entire score specific area for histological analysis. The surface-intermediate-base scoring method can be readily harnessed in real-world clinical practice and accurately mirrors histopathological analysis for quantification and reporting of healthy renal margin thickness removed during tumor excision. Copyright © 2015 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

  12. Constraints Imposed by Rift Inheritance on the Compressional Reactivation of a Hyperextended Margin: Mapping Rift Domains in the North Iberian Margin and in the Cantabrian Mountains

    NASA Astrophysics Data System (ADS)

    Cadenas, P.; Fernández-Viejo, G.; Pulgar, J. A.; Tugend, J.; Manatschal, G.; Minshull, T. A.

    2018-03-01

    The Alpine Pyrenean-Cantabrian orogen developed along the plate boundary between Iberia and Europe, involving the inversion of Mesozoic hyperextended basins along the southern Biscay margin. Thus, this margin represents a natural laboratory to analyze the control of structural rift inheritance on the compressional reactivation of a continental margin. With the aim to identify former rift domains and investigate their role during the subsequent compression, we performed a structural analysis of the central and western North Iberian margin, based on the interpretation of seismic reflection profiles and local constraints from drill-hole data. Seismic interpretations and published seismic velocity models enabled the development of crustal thickness maps that helped to constrain further the offshore and onshore segmentation. Based on all these constraints, we present a rift domain map across the central and western North Iberian margin, as far as the adjacent western Cantabrian Mountains. Furthermore, we provide a first-order description of the margin segmentation resulting from its polyphase tectonic evolution. The most striking result is the presence of a hyperthinned domain (e.g., Asturian Basin) along the central continental platform that is bounded to the north by the Le Danois High, interpreted as a rift-related continental block separating two distinctive hyperextended domains. From the analysis of the rift domain map and the distribution of reactivation structures, we conclude that the landward limit of the necking domain and the hyperextended domains, respectively, guide and localize the compressional overprint. The Le Danois block acted as a local buttress, conditioning the inversion of the Asturian Basin.

  13. 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.

  14. Finite Element Analysis of Magnetoelastic Plate Problems.

    DTIC Science & Technology

    1981-08-01

    deformation and in the incremental large deformation analysis, respectively. The classical Kirchhoff assumption of the undeformable normal to the midsurface is...current density , is constant across the thickness of the plate and is parallel to the midsurface of the plate; (2) the normal component of the

  15. The p-version of the finite element method in incremental elasto-plastic analysis

    NASA Technical Reports Server (NTRS)

    Holzer, Stefan M.; Yosibash, Zohar

    1993-01-01

    Whereas the higher-order versions of the finite elements method (the p- and hp-version) are fairly well established as highly efficient methods for monitoring and controlling the discretization error in linear problems, little has been done to exploit their benefits in elasto-plastic structural analysis. Aspects of incremental elasto-plastic finite element analysis which are particularly amenable to improvements by the p-version is discussed. These theoretical considerations are supported by several numerical experiments. First, an example for which an analytical solution is available is studied. It is demonstrated that the p-version performs very well even in cycles of elasto-plastic loading and unloading, not only as compared to the traditional h-version but also in respect to the exact solution. Finally, an example of considerable practical importance - the analysis of a cold-worked lug - is presented which demonstrates how the modeling tools offered by higher-order finite element techniques can contribute to an improved approximation of practical problems.

  16. The Energy Forum of Sri Lanka: Working toward appropriate expertise

    NASA Astrophysics Data System (ADS)

    Nieusma, Dean

    Taking my cue from the knowledge base and practices comprising appropriate technology development, and building on politics of expertise scholarship, this dissertation develops the concept of appropriate expertise: the combination of social and technical competences required to address marginalization through technological interventions. The dissertation asks what appropriate expertise looks like "on the ground" in the context of development as practiced by an exceptional group of technology designers from the Energy Forum of Sri Lanka: What design goals did they strive toward? What challenges did they face? What strategies did they employ? In an effort to answer these questions, the dissertation looks at how these designers interacted across a range of contexts with a broad spectrum of people and institutions, each with its own expertise to draw upon. In particular, it looks at how they situated their work in a highly contoured field of social power, where different types of expertise were used as resources for reinforcing or resisting existing power relations. I use the concept relations of expertise to denote the structure of expert interactions across multiple contexts of activity. Although this concept links to broad political-economic conditions that order varied expert practices, my analytic focus is at a different level: the situated experiences of expert practitioners. By starting with ground-level practices and understandings, I argue that creating new relations of expertise---that is, changing the nature of the interactions among experts and between experts and those they work with---is the key way my informants worked to legitimate marginalized perspectives and thereby empower marginalized social groups around technology-development practices. Appropriate expertise enables the creation of appropriate technologies, but it does more. It enables the creation of new relations of expertise, both through inspiring new forms of interpersonal interaction surrounding technology development and through incremental modification of existing decision-making structures to allow a more diverse group stakeholders to come together around technology decision making in the context of development.

  17. Prostate Localization on Daily Cone-Beam Computed Tomography Images: Accuracy Assessment of Similarity Metrics

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

    Kim, Jinkoo, E-mail: jkim3@hfhs.or; Hammoud, Rabih; Pradhan, Deepak

    2010-07-15

    Purpose: To evaluate different similarity metrics (SM) using natural calcifications and observation-based measures to determine the most accurate prostate and seminal vesicle localization on daily cone-beam CT (CBCT) images. Methods and Materials: CBCT images of 29 patients were retrospectively analyzed; 14 patients with prostate calcifications (calcification data set) and 15 patients without calcifications (no-calcification data set). Three groups of test registrations were performed. Test 1: 70 CT/CBCT pairs from calcification dataset were registered using 17 SMs (6,580 registrations) and compared using the calcification mismatch error as an endpoint. Test 2: Using the four best SMs from Test 1, 75 CT/CBCTmore » pairs in the no-calcification data set were registered (300 registrations). Accuracy of contour overlays was ranked visually. Test 3: For the best SM from Tests 1 and 2, accuracy was estimated using 356 CT/CBCT registrations. Additionally, target expansion margins were investigated for generating registration regions of interest. Results: Test 1-Incremental sign correlation (ISC), gradient correlation (GC), gradient difference (GD), and normalized cross correlation (NCC) showed the smallest errors ({mu} {+-} {sigma}: 1.6 {+-} 0.9 {approx} 2.9 {+-} 2.1 mm). Test 2-Two of the three reviewers ranked GC higher. Test 3-Using GC, 96% of registrations showed <3-mm error when calcifications were filtered. Errors were left/right: 0.1 {+-} 0.5mm, anterior/posterior: 0.8 {+-} 1.0mm, and superior/inferior: 0.5 {+-} 1.1 mm. The existence of calcifications increased the success rate to 97%. Expansion margins of 4-10 mm were equally successful. Conclusion: Gradient-based SMs were most accurate. Estimated error was found to be <3 mm (1.1 mm SD) in 96% of the registrations. Results suggest that the contour expansion margin should be no less than 4 mm.« less

  18. The effect of on-line position correction on the dose distribution in focal radiotherapy for bladder cancer

    PubMed Central

    van Rooijen, Dominique C; van de Kamer, Jeroen B; Pool, René; Hulshof, Maarten CCM; Koning, Caro CE; Bel, Arjan

    2009-01-01

    Background The purpose of this study was to determine the dosimetric effect of on-line position correction for bladder tumor irradiation and to find methods to predict and handle this effect. Methods For 25 patients with unifocal bladder cancer intensity modulated radiotherapy (IMRT) with 5 beams was planned. The requirement for each plan was that 99% of the target volume received 95% of the prescribed dose. Tumor displacements from -2.0 cm to 2.0 cm in each dimension were simulated, using 0.5 cm increments, resulting in 729 simulations per patient. We assumed that on-line correction for the tumor was applied perfectly. We determined the correlation between the change in D99% and the change in path length, which is defined here as the distance from the skin to the isocenter for each beam. In addition the margin needed to avoid underdosage was determined and the probability that an underdosage occurs in a real treatment was calculated. Results Adjustments for tumor displacement with perfect on-line position correction resulted in an altered dose distribution. The altered fraction dose to the target varied from 91.9% to 100.4% of the prescribed dose. The mean D99% (± SD) was 95.8% ± 1.0%. There was a modest linear correlation between the difference in D99% and the change in path length of the beams after correction (R2 = 0.590). The median probability that a systematic underdosage occurs in a real treatment was 0.23% (range: 0 - 24.5%). A margin of 2 mm reduced that probability to < 0.001% in all patients. Conclusion On-line position correction does result in an altered target coverage, due to changes in average path length after position correction. An extra margin can be added to prevent underdosage. PMID:19775479

  19. Microleakage of Posterior Composite Restorations with Fiber Inserts Using two Adhesives after ging

    PubMed Central

    Sharafeddin, F; Yousefi, H; Modiri, Sh; Tondari, A; Safaee Jahromi, SR

    2013-01-01

    Statement of Problem: Microleakage is one of the most frequent problems associated with resin composites, especially at the gingival margin of posterior restorations. Insertion of fibers in composite restorations can reduce the total amount of composite and help to decrease the shrinkage. Purpose: The aim of this study was to evaluate the effect of polyethylene fiber inserts on gingival microleakage of class II composite restorations using two different adhesive systems. Materials and Method: In this experimental study, class II cavities were prepared on 60 premolars. The gingival floor was located 1.0 mm below the CEJ. Dimension of each cavity were 3 mm buccolingually and 1.5 mm in axial depth. The specimens were divided into 4 groups according to the adhesive type and fiber insert (n=4). Single bond and Clearfill SE bond and Filtek p60 were used to restore the cavities. In groups without fiber inserts composite was adapted onto cavities using layering technique. For cavities with fiber inserts, 3 mm piece of fiber insert was placed onto the composite increment and cured. The specimens were stored in distilled water at 37oC for 6 months. All specimens were subjected to 3000 thermo-cycling. The tooth surfaces except for 1 mm around the restoration margins covered with two layers of nail varnish .The teeth were immersed in 2% Basic Fuchsin for 24 hours, then rinsed and sectioned mesiodistally. The microleakage was determined under a stereomicroscope (40X). Data were statistically analyzed by Kruskal-wallis and Mann-Whitney U tests (p< 0.05). Results: The Kruskal-Wallis test revealed no significant differences in mean microleakage scores among all groups (p= 0.281). Conclusion: Use of polyethylene fiber inserts and etch-and-rinse and self-etch adhesives had no effect on microleakage in class II resin composite restorations with gingival margins below the CEJ after 6- month water storage. PMID:24724129

  20. The role of HCG increment in the 48h prior to methotrexate treatment as a predictor for treatment success.

    PubMed

    Cohen, Aviad; Almog, Benny; Cohen, Yoni; Bibi, Guy; Rimon, Eli; Levin, Ishai

    2017-04-01

    To evaluate the role HCG change in the 48h prior to methotrexate treatment as a predictor for treatment success. Medical records of all women who were diagnosed with ectopic pregnancy between January 2001 and June 2013 were reviewed. Four hundred and nine patients received methotrexate due to ectopic pregnancy. The "single dose" methotrexate protocol with 50mg/m 2 was administered to patients with progressing ectopic pregnancy. HCG levels in days 1, 4 and 7 were used to evaluate methotrexate treatment success. The percentage of HCG change in the 48h prior to methotrexate treatment was compared between patients who were successfully treated and those who failed treatment with methotrexate. Single dose methotrexate was successful in 309 patients (75.4%, success group). The medians of HCG change in the 48h prior to methotrexate administration were significantly higher in the "failure group" (21% vs. 4%, p<0.01). In a logistic regression analysis, the of HCG percent increment prior to methotrexate administration was shown to be an independent predictor for treatment outcome. Receiver operator characteristic curve for HCG percent change was 0.751, at a cutoff value of HCG increment <12% the positive predictive value for treatment success reached 86%. Percentage of HCG increment in the 48h prior to methotrexate administration is an independent predictor for methotrexate treatment success. HCG increment <12% prior to methotrexate treatment is a good predictor for treatment success. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. The value of crossdating to retain high-frequency variability, climate signals, and extreme events in environmental proxies.

    PubMed

    Black, Bryan A; Griffin, Daniel; van der Sleen, Peter; Wanamaker, Alan D; Speer, James H; Frank, David C; Stahle, David W; Pederson, Neil; Copenheaver, Carolyn A; Trouet, Valerie; Griffin, Shelly; Gillanders, Bronwyn M

    2016-07-01

    High-resolution biogenic and geologic proxies in which one increment or layer is formed per year are crucial to describing natural ranges of environmental variability in Earth's physical and biological systems. However, dating controls are necessary to ensure temporal precision and accuracy; simple counts cannot ensure that all layers are placed correctly in time. Originally developed for tree-ring data, crossdating is the only such procedure that ensures all increments have been assigned the correct calendar year of formation. Here, we use growth-increment data from two tree species, two marine bivalve species, and a marine fish species to illustrate sensitivity of environmental signals to modest dating error rates. When falsely added or missed increments are induced at one and five percent rates, errors propagate back through time and eliminate high-frequency variability, climate signals, and evidence of extreme events while incorrectly dating and distorting major disturbances or other low-frequency processes. Our consecutive Monte Carlo experiments show that inaccuracies begin to accumulate in as little as two decades and can remove all but decadal-scale processes after as little as two centuries. Real-world scenarios may have even greater consequence in the absence of crossdating. Given this sensitivity to signal loss, the fundamental tenets of crossdating must be applied to fully resolve environmental signals, a point we underscore as the frontiers of growth-increment analysis continue to expand into tropical, freshwater, and marine environments. © 2016 John Wiley & Sons Ltd.

  2. Petrogenesis of the Zheduoshan Cenozoic granites in the eastern margin of Tibet: Constraints on the initial activity of the Xianshuihe Fault

    NASA Astrophysics Data System (ADS)

    Lai, Shao-cong; Zhao, Shao-wei

    2018-06-01

    The Zheduoshan Miocene granitic pluton is exposed at the eastern margin of Tibet and along the strike-slip Xianshuihe Fault, and is the product of syn-tectonic magmatism closely related to this fault. This paper is focused on the petrogenesis of different granitic lithological units in the Zheduoshan composite intrusion, and the results of geochronology and lithology show that the Zheduoshan Miocene granitic pluton is incremental assembly by three stages of granitic magma influx and growth, represented by fine-grain biotite granite at 18.0 Ma, corase-grain and porphyraceous biotite monzogranite at 16.0 Ma and medium-grain two-mica monzogranite at 14.0 Ma. Combining with the geochemical signatures, these granitic rocks have high intial 87Sr/86Sr ratios, enriched Nd and Hf isotopic compositions, revealing that the sources of these granitic rocks are metabasatic rocks for fine-grain biotite granite, greywackes for coarse-grain biotite monzogranite and medium-grain monzogranite. These granites have high Sr/Y ratios, revealing that these granitic magma form at high pressure condition. The Sr/Y ratios and calculated crystallization pressure gradually decreased, implying the pressure gradually decreasing with the formation of these three stages of granites, which is probably caused by the tectonic mechanism transition from compression to strike-slip extension during the generation of these granites at 18.0-14.4 Ma. This tectonic mechanism change implied the initial activity of Xianshuihe Fault at least before 14.4 Ma.

  3. Creating breakthroughs at 3M.

    PubMed

    von Hippel, E; Thomke, S; Sonnack, M

    1999-01-01

    Most senior managers want their product development teams to create break-throughs--new products that will allow their companies to grow rapidly and maintain high margins. But more often they get incremental improvements to existing products. That's partly because companies must compete in the short term. Searching for breakthroughs is expensive and time consuming; line extensions can help the bottom line immediately. In addition, developers simply don't know how to achieve breakthroughs, and there is usually no system in place to guide them. By the mid-1990s, the lack of such a system was a problem even for an innovative company like 3M. Then a project team in 3M's Medical-Surgical Markets Division became acquainted with a method for developing breakthrough products: the lead user process. The process is based on the fact that many commercially important products are initially thought of and even prototyped by "lead users"--companies, organizations, or individuals that are well ahead of market trends. Their needs are so far beyond those of the average user that lead users create innovations on their own that may later contribute to commercially attractive breakthroughs. The lead user process transforms the job of inventing breakthroughs into a systematic task of identifying lead users and learning from them. The authors explain the process and how the 3M project team successfully navigated through it. In the end, the team proposed three major new product lines and a change in the division's strategy that has led to the development of breakthrough products. And now several more divisions are using the process to break away from incrementalism.

  4. Marginal fit and photoelastic stress analysis of CAD-CAM and overcast 3-unit implant-supported frameworks.

    PubMed

    Presotto, Anna Gabriella Camacho; Bhering, Cláudia Lopes Brilhante; Mesquita, Marcelo Ferraz; Barão, Valentim Adelino Ricardo

    2017-03-01

    Several studies have shown the superiority of computer-assisted design and computer-assisted manufacturing (CAD-CAM) technology compared with conventional casting. However, an advanced technology exists for casting procedures (the overcasting technique), which may serve as an acceptable and affordable alternative to CAD-CAM technology for fabricating 3-unit implant-supported fixed dental prostheses (FDPs). The purpose of this in vitro study was to evaluate, using quantitative photoelastic analysis, the effect of the prosthetic framework fabrication method (CAD-CAM and overcasting) on the marginal fit and stress transmitted to implants. The correlation between marginal fit and stress was also investigated. Three-unit implant-supported FDP frameworks were made using the CAD-CAM (n=10) and overcasting (n=10) methods. The frameworks were waxed to simulate a mandibular first premolar (PM region) to first molar (M region) FDP using overcast mini-abutment cylinders. The wax patterns were overcast (overcast experimental group) or scanned to obtain the frameworks (CAD-CAM control group). All frameworks were fabricated from cobalt-chromium (CoCr) alloy. The marginal fit was analyzed according to the single-screw test protocol, obtaining an average value for each region (M and PM) and each framework. The frameworks were tightened for the photoelastic model with standardized 10-Ncm torque. Stress was measured by quantitative photoelastic analysis. The results were submitted to the Student t test, 2-way ANOVA, and Pearson correlation test (α=.05). The framework fabrication method (FM) and evaluation site (ES; M and PM regions) did not affect the marginal fit values (P=.559 for FM and P=.065 for ES) and stress (P=.685 for FM and P=.468 for ES) in the implant-supported system. Positive correlations between marginal fit and stress were observed (CAD-CAM: r=0.922; P<.001; overcast: r=0.908; P<.001). CAD-CAM and overcasting methods present similar marginal fit and stress values for 3-unit FDP frameworks. The decreased marginal fit of frameworks induces greater stress in the implant-supported system. Copyright © 2016 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  5. A table of intensity increments.

    DOT National Transportation Integrated Search

    1966-01-01

    Small intensity increments can be produced by adding larger intensity increments. A table is presented covering the range of small intensity increments from 0.008682 through 6.020 dB in 60 large intensity increments of 1 dB.

  6. Incremental Upgrade of Legacy Systems (IULS)

    DTIC Science & Technology

    2001-04-01

    analysis task employed SEI’s Feature-Oriented Domain Analysis methodology (see FODA reference) and included several phases: • Context Analysis • Establish...Legacy, new Host and upgrade system and software. The Feature Oriented Domain Analysis approach ( FODA , see SUM References) was used for this step...Feature-Oriented Domain Analysis ( FODA ) Feasibility Study (CMU/SEI-90-TR- 21, ESD-90-TR-222); Software Engineering Institute, Carnegie Mellon University

  7. Stereotactic Radiosurgery of the Postoperative Resection Cavity for Brain Metastases: Prospective Evaluation of Target Margin on Tumor Control

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

    Choi, Clara Y.H.; Chang, Steven D.; Gibbs, Iris C.

    2012-10-01

    Purpose: Given the neurocognitive toxicity associated with whole-brain irradiation (WBRT), approaches to defer or avoid WBRT after surgical resection of brain metastases are desirable. Our initial experience with stereotactic radiosurgery (SRS) targeting the resection cavity showed promising results. We examined the outcomes of postoperative resection cavity SRS to determine the effect of adding a 2-mm margin around the resection cavity on local failure (LF) and toxicity. Patients and Methods: We retrospectively evaluated 120 cavities in 112 patients treated from 1998-2009. Factors associated with LF and distant brain failure (DF) were analyzed using competing risks analysis, with death as a competingmore » risk. The overall survival (OS) rate was calculated by the Kaplan-Meier product-limit method; variables associated with OS were evaluated using the Cox proportional hazards and log rank tests. Results: The 12-month cumulative incidence rates of LF and DF, with death as a competing risk, were 9.5% and 54%, respectively. On univariate analysis, expansion of the cavity with a 2-mm margin was associated with decreased LF; the 12-month cumulative incidence rates of LF with and without margin were 3% and 16%, respectively (P=.042). The 12-month toxicity rates with and without margin were 3% and 8%, respectively (P=.27). On multivariate analysis, melanoma histology (P=.038) and number of brain metastases (P=.0097) were associated with higher DF. The median OS time was 17 months (range, 2-114 months), with a 12-month OS rate of 62%. Overall, WBRT was avoided in 72% of the patients. Conclusion: Adjuvant SRS targeting the resection cavity of brain metastases results in excellent local control and allows WBRT to be avoided in a majority of patients. A 2-mm margin around the resection cavity improved local control without increasing toxicity compared with our prior technique with no margin.« less

  8. Cervical and Incisal Marginal Discrepancy in Ceramic Laminate Veneering Materials: A SEM Analysis.

    PubMed

    Ranganathan, Hemalatha; Ganapathy, Dhanraj M; Jain, Ashish R

    2017-01-01

    Marginal discrepancy influenced by the choice of processing material used for the ceramic laminate veneers needs to be explored further for better clinical application. This study aimed to evaluate the amount of cervical and incisal marginal discrepancy associated with different ceramic laminate veneering materials. This was an experimental, single-blinded, in vitro trial. Ten central incisors were prepared for laminate veneers with 2 mm uniform reduction and heavy chamfer finish line. Ceramic laminate veneers fabricated over the prepared teeth using four different processing materials were categorized into four groups as Group I - aluminous porcelain veneers, Group II - lithium disilicate ceramic veneers, Group III - lithium disilicate-leucite-based veneers, Group IV - zirconia-based ceramic veneers. The cervical and incisal marginal discrepancy was measured using a scanning electron microscope. ANOVA and post hoc Tukey honest significant difference (HSD) tests were used for statistical analysis. The cervical and incisal marginal discrepancy for four groups was Group I - 114.6 ± 4.3 μm, 132.5 ± 6.5 μm, Group II - 86.1 ± 6.3 μm, 105.4 ± 5.3 μm, Group III - 71.4 ± 4.4 μm, 91.3 ± 4.7 μm, and Group IV - 123.1 ± 4.1 μm, 142.0 ± 5.4 μm. ANOVA and post hoc Tukey HSD tests observed a statistically significant difference between the four test specimens with regard to cervical marginal discrepancy. The cervical and incisal marginal discrepancy scored F = 243.408, P < 0.001 and F = 180.844, P < 0.001, respectively. This study concluded veneers fabricated using leucite reinforced lithium disilicate exhibited the least marginal discrepancy followed by lithium disilicate ceramic, aluminous porcelain, and zirconia-based ceramics. The marginal discrepancy was more in the incisal region than in the cervical region in all the groups.

  9. Comparison of hydrothermal activity between the Adriatic and the Red Sea rift margins

    NASA Astrophysics Data System (ADS)

    Ball, Philip; Incerpi, Nicolò; Birkle, Peter; Lacsamana, Elizabeth; Manatschal, Gianreto; Agar, Susan; Zhang, Shuo; Borsato, Ron

    2017-04-01

    Detailed field studies, and access to high-quality seismic reflection and refraction data have led to an improved understanding of the architecture and evolution of magma poor and magma rich margins. Associated with the spatial-temporal evolution of the rift, it is evident that there are evolving, extensive, fluid-rock interactions due to the infiltration of fluids within the sediment, basement and lithospheric mantle. Key questions therefore arise: What are the different fluid-rock reactions that can be typed to different geodynamic stages of the rift evolution? What are their compositions and how do they interact with their environment (basement, sediments, evaporites, hydrosphere, and magmatism)? What are the implications for the evolution of the margin rheology, thermal structure, depositional environments/organic matter maturity, and reservoir quality? The Adriatic paleo-rifted margin is preserved in both SE Switzerland and northern Italy. The field exposures provide a unique opportunity to study the fluid flow history of a hyperextended magma poor extensional margin. Analysis of breccias, cement veins and replacement minerals reveal that the margin records a complex, long-lasting history of dolomitization, calcification and silicification during the Jurassic rifting. The Red Sea by contrast is a young rifted margin. It differs from the paleo-Adriatic margin by several characteristics: volcanism is more evident, and syn-tectonic sediments, including evaporites (halite and anhydrite) are thicker. Several core and fluid samples are available from both onshore and offshore wells, which reveal rift-related hydrothermal alteration. In addition, we find evidence for the presence of an extreme dynamic hydraulic system with infiltration of surface water into sub-salt units during Late Pleistocene. In this study we present results from petrographic and geochemical analysis of basement and sedimentary rocks from Adriatic field-derived samples and core/subsurface fluid samples for the Eastern Red Sea margin. The results are presented using rift domain interpretations, thereby enabling the simple comparison of the observed hydrothermal alteration within a first-order (spatial temporal) rift geodynamic framework.

  10. A status report on the characterization of the microgravity environment of the International Space Station

    NASA Technical Reports Server (NTRS)

    Jules, Kenol; McPherson, Kevin; Hrovat, Kenneth; Kelly, Eric; Reckart, Timothy

    2004-01-01

    A primary objective of the International Space Station is to provide a long-term quiescent environment for the conduct of scientific research for a variety of microgravity science disciplines. Since continuous human presence on the space station began in November 2000 through the end of Increment-6, over 1260 hours of crew time have been allocated to research. However, far more research time has been accumulated by experiments controlled on the ground. By the end of the time period covered by this paper (end of Increment-6), the total experiment hours performed on the station are well over 100,000 hours (Expedition 6 Press Kit: Station Begins Third Year of Human Occupation, Boeing/USA/NASA, October 25, 2002). This paper presents the results of the on-going effort by the Principal Investigator Microgravity Services project, at NASA Glenn Research Center, in Cleveland, Ohio, to characterize the microgravity environment of the International Space Station in order to keep the microgravity scientific community apprised of the reduced gravity environment provided by the station for the performance of space experiments. This paper focuses on the station microgravity environment for Increments 5 and 6. During that period over 580 Gbytes of acceleration data were collected, out of which over 34,790 hours were analyzed. The results presented in this paper are divided into two sections: quasi-steady and vibratory. For the quasi-steady analysis, over 7794 hours of acceleration data were analyzed, while over 27,000 hours were analyzed for the vibratory analysis. The results of the data analysis are presented in this paper in the form of a grand summary for the period under consideration. For the quasi-steady acceleration response, results are presented in the form of a 95% confidence interval for the station during "normal microgravity mode operations" for the following three attitudes: local vertical local horizontal, X-axis perpendicular to the orbit plane and the Russian torque equilibrium attitude. The same analysis was performed for the station during "non-microgravity mode operations" to assess the station quasi-steady acceleration environment over a long period of time. The same type of analysis was performed for the vibratory, but a 95th percentile benchmark was used, which shows the overall acceleration magnitude during Increments 5 and 6. The results, for both quasi-steady and vibratory acceleration response, show that the station is not yet meeting the microgravity requirements during the microgravity mode operations. However, it should be stressed that the requirements apply only at assembly complete, whereas the results presented below apply up to the station's configuration at the end of Increment-6. c2004 Elsevier Ltd. All rights reserved.

  11. Circumferential fit assessment of CAD/CAM single crowns--a pilot investigation on a new virtual analytical protocol.

    PubMed

    Matta, Ragai E; Schmitt, Johannes; Wichmann, Manfred; Holst, Stefan

    2012-10-01

    Techniques currently applied to determine the marginal accuracy of dental crown restorations yield inadequate information. This investigation aimed to test a new virtual approach for determining the precision of fit of single-crown copings. Zirconia single crown copings were manufactured on 10 gypsum, single-tooth master casts with two different established computer-aided design/computer-assisted manufacture (CAD/CAM) systems (groups A and B). After cementation, the circumferential fit was assessed with an industrial noncontact scanner and virtual 3D analysis, following a triple-scan protocol. Marginal fit was determined by virtual sectioning; each abutment-coping complex was digitally sliced in 360 vertical sections (1 degree per section). Standardized measurement distances for analyzing the marginal fit (z, xy, xyz) were selected, and a crosshair alignment was utilized to determine whether crowns were horizontally and/or vertically too large or small. The Mann-Whitney test was applied to test for differences between groups. Significant differences in the xy direction (P = .008) were measured between groups. Group A showed a greater number of horizontally overextended margins and a higher frequency of xy distances greater than 150 Μm, in addition to a tendency for excessive z distances (P = .095). The mean marginal gap values were clinically acceptable in the present investigation; however, a full circumferential analysis revealed significant differences in marginal coping quality.

  12. A comparison between three different pit and fissure sealants with regard to marginal integrity.

    PubMed

    Fernandes, Kristlee Sabrin; Chalakkal, Paul; de Ataide, Ida de Noronha; Pavaskar, Rajdeep; Fernandes, Precylia Philo; Soni, Harleen

    2012-04-01

    THE AIM OF THIS STUDY IS TO COMPARE THE OCCURRENCE OF ENAMEL FRACTURES, SEALANT FRACTURES AND MARGINAL FISSURES AFTER PLACEMENT OF THREE SEALANTS: Helioseal F, Conseal F and Clinpro. Thirty individuals between 13 and 15 years of age, diagnosed with pit and fissure caries by visual and DIAGNOdent examination, were chosen for sealant placement on their mandibular molars. The sealants were placed at random, after which, impressions were made with polyvinyl siloxane and casts were fabricated. Dies were prepared, each of which were sputter coated with gold in order to be examined under a scanning electron microscope. The following morphologies were analyzed from dies from each of the sealant groups: Continuous margins, sealant fractures, marginal fissures and enamel fractures. After six months, they were recalled for impression making. Dies were prepared and microscopically analyzed as mentioned. Based on the time of evaluation, there were two groups: Initial group (soon after placement) and final group (after six months). Statistical analysis was done using the paired 't' test and One-way analysis of variance (ANOVA). Clinpro had the greatest fracture resistance, followed by Conseal F and Helioseal F. The occurrence of marginal fissure was found to be least with Clinpro.

  13. Sickness absence, marginality, and medically unexplained physical symptoms: a focus-group study of patients' experiences.

    PubMed

    Aamland, Aase; Werner, Erik L; Malterud, Kirsti

    2013-06-01

    Medically unexplained physical symptoms (MUPS) form a major cause of sickness absence. The purpose of this study was to explore factors which may influence further marginalization among patients with MUPS on long-term sickness absence. Two focus-group discussions were conducted with a purposive sample of 12 participants, six men and six women, aged 24-59 years. Their average duration of sickness absence was 10.5 months. Participants were invited to share stories about experiences from the process leading to the ongoing sickness absence, with a focus on the causes being medically unexplained. Systematic text condensation was applied for analysis. Inspired by theories of marginalization and coping, the authors searched for knowledge of how patients' positive resources can be mobilized to counteract processes of marginality. Analysis revealed how invisible symptoms and lack of objective findings were perceived as an additional burden to the sickness absence itself. Factors that could counteract further marginalization were a supportive social network, positive coping strategies such as keeping to the daily schedule and physical activity, and positive attention and confidence from professionals. Confidence from both personal and professional contacts is crucial. GPs have an important and appreciated role in this aspect.

  14. 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.

  15. 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.

  16. Gamma knife radiosurgery for vestibular schwannomas: tumor control and functional preservation in 70 patients.

    PubMed

    Arthurs, Benjamin J; Lamoreaux, Wayne T; Mackay, Alexander R; Demakas, John J; Giddings, Neil A; Fairbanks, Robert K; Cooke, Barton S; Elaimy, Ameer L; Peressini, Ben; Lee, Christopher M

    2011-06-01

    We present the previously unreported outcomes of 70 patients treated with Gamma knife radiosurgery for vestibular schwannoma (VS), including comprehensive analysis of clinical outcomes and the effects of lower marginal doses. We performed a retrospective study of patients treated for VS at Gamma knife of Spokane between 2003 and 2008. Endpoints measured include tumor control, hearing preservation, and facial nerve preservation, including the effect of tumor size and marginal dose. Statistical analysis was performed with Wilcoxon signed-rank test, paired Student t test, Mann-Whitney U test, Kendall's rank correlation, Fisher exact test, and Liddell's exact χ(2) test for matched pairs. With a mean follow-up of 26 months, 93.8% of tumors either shrank or remained static after receiving a mean marginal dose of 12.7 Gy. Tumor control was independent of marginal dose or tumor size. Hearing preservation was achieved in 64% of patients with serviceable function before the treatment. Hearing changes were independent of dose or tumor size. Preservation of good facial nerve function was achieved in 95% of patients. Post-treatment hydrocephalus occurred in 4.4% of patients, but no other significant morbidities were elucidated. In the treatment of VS, contemporary radiosurgical techniques and the use of marginal doses below 13 Gy offer excellent tumor control, at high rates relative to surgical intervention. These findings are independent of marginal dose and tumor size. Patients should be informed about the benefits and risks of radiosurgery and microsurgery before choosing an intervention. Further analysis of post-treatment outcomes should be encouraged as follow-up times increase and the treatment protocols continue to evolve.

  17. The assessment of mucosal surgical margins in head and neck cancer surgery with narrow band imaging.

    PubMed

    Šifrer, Robert; Urbančič, Jure; Strojan, Primož; Aničin, Aleksandar; Žargi, Miha

    2017-07-01

    The diagnostic gain of narrow band imaging in the definition of surgical margins in the treatment of head and neck cancer was evaluated. A prospective study, blinded to the pathologist, with historical comparison. The study group included 45 patients subjected to the intraoperative definition of margins by narrow band imaging. The control group included 55 patients who had undergone standard definition of margins. All patients underwent resection of the tumor and frozen section analysis of superficial margins. The rate of initial R 0 resection and the ratio of histologically negative margins for both groups were statistically compared. The rate of initial R 0 resection in the study group and in the control group was 88.9% and 70.9% (P = .047), and the ratio of histologically negative margins was 95.9% and 88.4% (P = .017), respectively. Narrow band imaging reveals a microscopic extension of the tumor that could be effectively used to better define superficial margins and to achieve a higher rate of initial R 0 resections. 4 Laryngoscope, 127:1577-1582, 2017. © 2016 The American Laryngological, Rhinological and Otological Society, Inc.

  18. 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.

  19. International Space Station Increment-6/8 Microgravity Environment Summary Report November 2002 to April 2004

    NASA Technical Reports Server (NTRS)

    Jules, Kenol; Hrovat, Kenneth; Kelly, Eric; Reckart, Timothy

    2006-01-01

    This summary report presents the analysis results of some of the processed acceleration data measured aboard the International Space Station during the period of November 2002 to April 2004. Two accelerometer systems were used to measure the acceleration levels for the activities that took place during Increment-6/8. However, not all of the activities during that period were analyzed in order to keep the size of the report manageable. The National Aeronautics and Space Administration sponsors the Microgravity Acceleration Measurement System and the Space Acceleration Measurement System to support microgravity science experiments that require microgravity acceleration measurements. On April 19, 2001, both the Microgravity Acceleration Measurement System and the Space Acceleration Measurement System units were launched on STS-100 from the Kennedy Space Center for installation on the International Space Station. The Microgravity Acceleration Measurement System unit was flown to the station in support of science experiments requiring quasi-steady acceleration measurements, while the Space Acceleration Measurement System unit was flown to support experiments requiring vibratory acceleration measurement. Both acceleration systems are also used in support of the vehicle microgravity requirements verification as well as in support of the International Space Station support cadre. The International Space Station Increment-6/8 reduced gravity environment analysis presented in this report uses acceleration data collected by both sets of accelerometer systems: 1. The Microgravity Acceleration Measurement System, which consists of two sensors: the Orbital Acceleration Research Experiment Sensor Subsystem, a low frequency range sensor (up to 1 Hz), is used to characterize the quasi-steady environment for payloads and vehicle, and the High Resolution Accelerometer Package, which is used to characterize the vibratory environment up to 100 Hz. 2. The Space Acceleration Measurement System measures vibratory acceleration data in the range of 0.01 to 400 Hz. This summary report presents analysis of some selected quasi-steady and vibratory activities measured by these accelerometers during Increment-6/8 from November 2002 to April 2004.

  20. Cost-Effectiveness Analysis of the Introduction of HPV Vaccination of 9-Year-Old-Girls in Iran.

    PubMed

    Yaghoubi, Mohsen; Nojomi, Marzieh; Vaezi, Atefeh; Erfani, Vida; Mahmoudi, Susan; Ezoji, Khadijeh; Zahraei, Seyed Mohsen; Chaudhri, Irtaza; Moradi-Lakeh, Maziar

    2018-04-23

    To estimate the cost effectiveness of introducing the quadrivalent human papillomavirus (HPV) vaccine into the national immunization program of Iran. The CERVIVAC cost-effectiveness model was used to calculate incremental cost per averted disability-adjusted life-year by vaccination compared with no vaccination from both governmental and societal perspectives. Calculations were based on epidemiologic parameters from the Iran National Cancer Registry and other national data sources as well as from literature review. We estimated all direct and indirect costs of cervical cancer treatment and vaccination program. All future costs and benefits were discounted at 3% per year and deterministic sensitivity analysis was used. During a 10-year period, HPV vaccination was estimated to avert 182 cervical cancer cases and 20 deaths at a total vaccination cost of US $23,459,897; total health service cost prevented because of HPV vaccination was estimated to be US $378,646 and US $691,741 from the governmental and societal perspective, respectively. Incremental cost per disability-adjusted life-year averted within 10 years was estimated to be US $15,205 and US $14,999 from the governmental and societal perspective, respectively, and both are higher than 3 times the gross domestic product per capita of Iran (US $14,289). Sensitivity analysis showed variation in vaccine price, and the number of doses has the greatest volatility on the incremental cost-effectiveness ratio. Using a two-dose vaccination program could be cost-effective from the societal perspective (incremental cost-effectiveness ratio = US $11,849). Introducing a three-dose HPV vaccination program is currently not cost-effective in Iran. Because vaccine supplies cost is the most important parameter in this evaluation, considering a two-dose schedule or reducing vaccine prices has an impact on final conclusions. Copyright © 2018. Published by Elsevier Inc.

  1. Initial evaluation of rectal bleeding in young persons: a cost-effectiveness analysis.

    PubMed

    Lewis, James D; Brown, Alphonso; Localio, A Russell; Schwartz, J Sanford

    2002-01-15

    Evaluation of rectal bleeding in young patients is a frequent diagnostic challenge. To determine the relative cost-effectiveness of alternative diagnostic strategies for young patients with rectal bleeding. Cost-effectiveness analysis using a Markov model. Probability estimates were based on published medical literature. Cost estimates were based on Medicare reimbursement rates and published medical literature. Persons 25 to 45 years of age with otherwise asymptomatic rectal bleeding. The patient's lifetime. Modified societal perspective. Diagnostic strategies included no evaluation, colonoscopy, flexible sigmoidoscopy, barium enema, anoscopy, or any feasible combination of these procedures. Life expectancy and costs. For 35-year-old patients, the no-evaluation strategy yielded the least life expectancy. The incremental cost-effectiveness of flexible sigmoidoscopy compared with no evaluation or with any strategy incorporating anoscopy (followed by further evaluation if no anal disease was found on anoscopy) was less than $5300 per year of life gained. A strategy of flexible sigmoidoscopy plus barium enema yielded the greatest life expectancy, with an incremental cost of $23 918 per additional life-year gained compared with flexible sigmoidoscopy alone. As patient age at presentation of rectal bleeding increased, evaluation of the entire colon became more cost-effective. The incremental cost-effectiveness of flexible sigmoidoscopy plus barium enema compared with colonoscopy was sensitive to estimates of the sensitivity of the tests. In a probabilistic sensitivity analysis comparing flexible sigmoidoscopy with anoscopy followed by flexible sigmoidoscopy if needed, the middle 95th percentile of the distribution of the incremental cost-effectiveness ratios ranged from flexible sigmoidoscopy yielding an increased life expectancy at reduced cost to $52 158 per year of life gained (mean, $11 461 per year of life saved). Evaluation of the colon of persons 25 to 45 years of age with otherwise asymptomatic rectal bleeding increases the life expectancy at a cost comparable to that of colon cancer screening.

  2. Levonorgestrel Intrauterine Device as an Endometrial Cancer Prevention Strategy in Obese Women: A Cost-Effectiveness Analysis.

    PubMed

    Dottino, Joseph A; Hasselblad, Vic; Secord, Angeles Alvarez; Myers, Evan R; Chino, Junzo; Havrilesky, Laura J

    2016-10-01

    To estimate the cost-effectiveness of the levonorgestrel intrauterine device (IUD) as an endometrial cancer prevention strategy in obese women. A modified Markov model was used to compare IUD placement at age 50 with usual care among women with a body mass index (BMI, kg/m) 40 or greater or BMI 30 or greater. The effects of obesity on incidence and survival were incorporated. The IUD was assumed to confer a 50% reduction in cancer incidence over 5 years. Costs of IUD and cancer care were included. Clinical outcomes were cancer diagnosis and deaths from cancer. Incremental cost-effectiveness ratios were calculated in 2015 U.S. dollars per year of life saved. One-way and two-way sensitivity analyses and Monte Carlo probabilistic analyses were performed. For a 50 year old with BMI 40 or greater, the IUD strategy is costlier and more effective than usual care with an incremental cost-effectiveness ratio of $74,707 per year of life saved. If the protective effect of the levonorgestrel IUD is assumed to be 10 years, the incremental cost-effectiveness ratio decreases to $37,858 per year of life saved. In sensitivity analysis, a levonorgestrel IUD that reduces cancer incidence by at least 68% in women with BMIs of 40 or greater or costs less than $500 is potentially cost-effective. For BMI 30 or greater, the incremental cost-effectiveness ratio of IUD strategy is $137,223 per year of life saved compared with usual care. In Monte Carlo analysis, IUD placement for BMI 40 or greater is cost-effective in 50% of simulations at a willingness-to-pay threshold of $100,000 per year of life saved. The levonorgestrel IUD is a potentially cost-effective strategy for prevention of deaths from endometrial cancer in obese women.

  3. Determination of post-shakedown quantities of a pipe bend via the simplified theory of plastic zones compared with load history dependent incremental analysis

    NASA Astrophysics Data System (ADS)

    Vollrath, Bastian; Hübel, Hartwig

    2018-01-01

    The Simplified Theory of Plastic Zones (STPZ) may be used to determine post-shakedown quantities such as strain ranges and accumulated strains at plastic or elastic shakedown. The principles of the method are summarized. Its practical applicability is shown by the example of a pipe bend subjected to constant internal pressure along with cyclic in-plane bending or/and cyclic radial temperature gradient. The results are compared with incremental analyses performed step-by-step throughout the entire load history until the state of plastic shakedown is achieved.

  4. Effect of different resin luting cements on the marginal fit of lithium disilicate pressed crowns.

    PubMed

    Mounajjed, Radek; Salinas, Thomas J; Ingr, Tomas; Azar, Basel

    2017-11-15

    The vertical marginal discrepancy of restorations can increase upon cementation, and poor marginal fit can lead to cement dissolution, marginal discoloration, microleakage, and secondary caries. The amount of increase is related to the type of luting cement used, but how lithium disilicate pressed crowns are affected by different resin cements is unclear. The purpose of this in vitro study was to compare the effect of using different resin luting cements on the vertical marginal discrepancy of lithium disilicate pressed crowns. A total of 18 intact extracted mandibular third molars were disinfected in a solution of 10% formalin for 7 days and were then prepared to receive a ceramic crown. Impressions were made with polyvinyl siloxane and lithium disilicate pressed crowns made and cemented with 1 of 3 resin luting cements. The marginal discrepancy was measured at 4 points on the finishing line of each tooth, with optical microscopy at ×200 magnification before and after cementation. Statistical analysis was done with the Kruskal-Wallis test to compare the median marginal increase among the 3 groups. The least amount of marginal increase after cementation was with Harvard PremiumFlow cement, with an average marginal increase of 42 ±11 μm. RelyX Ultimate cement increased the margins by an average 45 ±29 μm. The highest marginal increase was found in the Enamel Plus HRi preheated composite resin group (116 ±47 μm). The marginal increase of pressed crowns cemented with preheated composite resin (Enamel Plus HRi) exceeded the clinically acceptable range of marginal discrepancy. Copyright © 2017 Editorial Council for the Journal of Prosthetic Dentistry. Published by Elsevier Inc. All rights reserved.

  5. Estimation of marginal abatement costs of CO2 in Chinese provinces under 2020 carbon emission rights allocation: 2005-2020.

    PubMed

    Duan, Fumei; Wang, Yong; Wang, Ying; Zhao, Han

    2018-06-16

    The calculation of marginal abatement costs of CO 2 plays a vital role in meeting China's 2020 emission reduction targets by providing reference for determining carbon tax and carbon trading pricing. However, most existing researches only used one method to discuss regional and industrial marginal abatement costs, and almost no studies predicted future marginal abatement costs from the perspective of CO 2 emission efficiency. To make up for the gaps, this paper first estimates marginal abatement costs of CO 2 in three major industries of 30 provinces in China from 2005 to 2015 based on three assumptions. Second, based on the principle of fairness and efficiency, China's 2020 emission reduction targets are decomposed by province. Based on the ZSG-C-DDF model, the marginal abatement costs of CO 2 in all provinces in China in 2020 are estimated and compared with the marginal abatement costs of 2005 to 2015. The results show that (1) from 2005 to 2015, marginal abatement costs of CO 2 in all provinces show a fluctuating upward trend; (2) compared with the marginal abatement costs of primary industry or tertiary industry, most provinces have lower marginal abatement costs for secondary industry; and (3) the average marginal abatement costs of CO 2 for China in 2020 are 2766.882 Yuan/tonne for the 40% carbon intensity reduction target and 3334.836 Yuan/tonne for the 45% target, showing that the higher the emission reduction target, the higher the marginal abatement costs of CO 2 . (4) Overall, the average marginal abatement costs of CO 2 in China by 2020 are higher than those in 2005-2015. The empirical analysis in this paper can provide multiple references for environmental policy makers.

  6. Space station (modular) mission analysis. Volume 1: Mission analysis

    NASA Technical Reports Server (NTRS)

    1971-01-01

    The mission analysis on the modular space station considers experimental requirements and options characterized by low initial cost and incremental manning. Features that affect initial development and early operating costs are identified and their impacts on the program are assessed. Considered are the areas of experiment, mission, operations, information management, and long life and safety analyses.

  7. Cost-utility analysis of percutaneous mitral valve repair in inoperable patients with functional mitral regurgitation in German settings.

    PubMed

    Borisenko, Oleg; Haude, Michael; Hoppe, Uta C; Siminiak, Tomasz; Lipiecki, Janusz; Goldberg, Steve L; Mehta, Nawzer; Bouknight, Omari V; Bjessmo, Staffan; Reuter, David G

    2015-05-14

    To determine the cost-effectiveness of the percutaneous mitral valve repair (PMVR) using Carillon® Mitral Contour System® (Cardiac Dimensions Inc., Kirkland, WA, USA) in patients with congestive heart failure accompanied by moderate to severe functional mitral regurgitation (FMR) compared to the prolongation of optimal medical treatment (OMT). Cost-utility analysis using a combination of a decision tree and Markov process was performed. The clinical effectiveness was determined based on the results of the Transcatheter Implantation of Carillon Mitral Annuloplasty Device (TITAN) trial. The mean age of the target population was 62 years, 77% of the patients were males, 64% of the patients had severe FMR and all patients had New York Heart Association functional class III. The epidemiological, cost and utility data were derived from the literature. The analysis was performed from the German statutory health insurance perspective over 10-year time horizon. Over 10 years, the total cost was €36,785 in the PMVR arm and €18,944 in the OMT arm. However, PMVR provided additional benefits to patients with an 1.15 incremental quality-adjusted life years (QALY) and an 1.41 incremental life years. The percutaneous procedure was cost-effective in comparison to OMT with an incremental cost-effectiveness ratio of €15,533/QALY. Results were robust in the deterministic sensitivity analysis. In the probabilistic sensitivity analysis with a willingness-to-pay threshold of €35,000/QALY, PMVR had a 84 % probability of being cost-effective. Percutaneous mitral valve repair may be cost-effective in inoperable patients with FMR due to heart failure.

  8. 48 CFR 3452.232-71 - Incremental funding.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 7 2013-10-01 2012-10-01 true Incremental funding. 3452....232-71 Incremental funding. As prescribed in 3432.705-2, insert the following provision in solicitations if a cost-reimbursement contract using incremental funding is contemplated: Incremental Funding...

  9. 48 CFR 3452.232-71 - Incremental funding.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 7 2014-10-01 2014-10-01 false Incremental funding. 3452....232-71 Incremental funding. As prescribed in 3432.705-2, insert the following provision in solicitations if a cost-reimbursement contract using incremental funding is contemplated: Incremental Funding...

  10. 48 CFR 3452.232-71 - Incremental funding.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 7 2012-10-01 2012-10-01 false Incremental funding. 3452....232-71 Incremental funding. As prescribed in 3432.705-2, insert the following provision in solicitations if a cost-reimbursement contract using incremental funding is contemplated: Incremental Funding...

  11. 48 CFR 3452.232-71 - Incremental funding.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 7 2011-10-01 2011-10-01 false Incremental funding. 3452....232-71 Incremental funding. As prescribed in 3432.705-2, insert the following provision in solicitations if a cost-reimbursement contract using incremental funding is contemplated: Incremental Funding...

  12. Station Blackout: A case study in the interaction of mechanistic and probabilistic safety analysis

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

    Curtis Smith; Diego Mandelli; Cristian Rabiti

    2013-11-01

    The ability to better characterize and quantify safety margins is important to improved decision making about nuclear power plant design, operation, and plant life extension. As research and development (R&D) in the light-water reactor (LWR) Sustainability (LWRS) Program and other collaborative efforts yield new data, sensors, and improved scientific understanding of physical processes that govern the aging and degradation of plant SSCs needs and opportunities to better optimize plant safety and performance will become known. The purpose of the Risk Informed Safety Margin Characterization (RISMC) Pathway R&D is to support plant decisions for risk-informed margin management with the aim tomore » improve economics, reliability, and sustain safety of current NPPs. In this paper, we describe the RISMC analysis process illustrating how mechanistic and probabilistic approaches are combined in order to estimate a safety margin. We use the scenario of a “station blackout” wherein offsite power and onsite power is lost, thereby causing a challenge to plant safety systems. We describe the RISMC approach, illustrate the station blackout modeling, and contrast this with traditional risk analysis modeling for this type of accident scenario.« less

  13. Pliocene Seasonality along the US Atlantic Coastal Plain Inferred from Growth Increment Analysis of Mercenaria carolinensis

    NASA Astrophysics Data System (ADS)

    Winkelstern, I. Z.; Surge, D. M.

    2010-12-01

    Pliocene sea surface temperature (SST) data from the US Atlantic coastal plain is currently insufficient for a detailed understanding of the climatic shifts that occurred during the period. Previous studies, based on oxygen isotope proxy data from marine shells and bryozoan zooid size analysis, have provided constraints on possible annual-scale SST ranges for the region. However, more data are required to fully understand the forcing mechanisms affecting regional Pliocene climate and evaluate modeled temperature projections. Bivalve sclerochronology (growth increment analysis) is an alternative proxy for SST that can provide annually resolved multi-year time series. The method has been validated in previous studies using modern Arctica, Chione, and Mercenaria. We analyzed Pliocene Mercenaria carolinensis shells using sclerochronologic methods and tested the hypothesis that higher SST ranges are reflected in shells selected from the warmest climate interval (3.5-3.3 Ma, upper Yorktown Formation, Virginia) and lower SST ranges are observable in shells selected from the subsequent cooling interval (2.4-1.8 Ma, Chowan River Formation, North Carolina). These results further establish the validity of growth increment analysis using fossil shells and provide the first large dataset (from the region) of reconstructed annual SST from floating time series during these intervals. These data will enhance our knowledge about a warm climate state that has been identified in the 2007 IPCC report as an analogue for expected global warming. Future work will expand this study to include sampling in Florida to gain detailed information about Pliocene SST along a latitudinal gradient.

  14. Cortical bone fracture analysis using XFEM - case study.

    PubMed

    Idkaidek, Ashraf; Jasiuk, Iwona

    2017-04-01

    We aim to achieve an accurate simulation of human cortical bone fracture using the extended finite element method within a commercial finite element software abaqus. A two-dimensional unit cell model of cortical bone is built based on a microscopy image of the mid-diaphysis of tibia of a 70-year-old human male donor. Each phase of this model, an interstitial bone, a cement line, and an osteon, are considered linear elastic and isotropic with material properties obtained by nanoindentation, taken from literature. The effect of using fracture analysis methods (cohesive segment approach versus linear elastic fracture mechanics approach), finite element type, and boundary conditions (traction, displacement, and mixed) on cortical bone crack initiation and propagation are studied. In this study cohesive segment damage evolution for a traction separation law based on energy and displacement is used. In addition, effects of the increment size and mesh density on analysis results are investigated. We find that both cohesive segment and linear elastic fracture mechanics approaches within the extended finite element method can effectively simulate cortical bone fracture. Mesh density and simulation increment size can influence analysis results when employing either approach, and using finer mesh and/or smaller increment size does not always provide more accurate results. Both approaches provide close but not identical results, and crack propagation speed is found to be slower when using the cohesive segment approach. Also, using reduced integration elements along with the cohesive segment approach decreases crack propagation speed compared with using full integration elements. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  15. A Multifaceted Intervention to Improve the Quality of Care of Children in District Hospitals in Kenya: A Cost-Effectiveness Analysis

    PubMed Central

    Barasa, Edwine W.; Ayieko, Philip; Cleary, Susan; English, Mike

    2012-01-01

    Background To improve care for children in district hospitals in Kenya, a multifaceted approach employing guidelines, training, supervision, feedback, and facilitation was developed, for brevity called the Emergency Triage and Treatment Plus (ETAT+) strategy. We assessed the cost effectiveness of the ETAT+ strategy, in Kenyan hospitals. Further, we estimate the costs of scaling up the intervention to Kenya nationally and potential cost effectiveness at scale. Methods and Findings Our cost-effectiveness analysis from the provider's perspective used data from a previously reported cluster randomized trial comparing the full ETAT+ strategy (n = 4 hospitals) with a partial intervention (n = 4 hospitals). Effectiveness was measured using 14 process measures that capture improvements in quality of care; their average was used as a summary measure of quality. Economic costs of the development and implementation of the intervention were determined (2009 US$). Incremental cost-effectiveness ratios were defined as the incremental cost per percentage improvement in (average) quality of care. Probabilistic sensitivity analysis was used to assess uncertainty. The cost per child admission was US$50.74 (95% CI 49.26–67.06) in intervention hospitals compared to US$31.1 (95% CI 30.67–47.18) in control hospitals. Each percentage improvement in average quality of care cost an additional US$0.79 (95% CI 0.19–2.31) per admitted child. The estimated annual cost of nationally scaling up the full intervention was US$3.6 million, approximately 0.6% of the annual child health budget in Kenya. A “what-if” analysis assuming conservative reductions in mortality suggests the incremental cost per disability adjusted life year (DALY) averted by scaling up would vary between US$39.8 and US$398.3. Conclusion Improving quality of care at scale nationally with the full ETAT+ strategy may be affordable for low income countries such as Kenya. Resultant plausible reductions in hospital mortality suggest the intervention could be cost-effective when compared to incremental cost-effectiveness ratios of other priority child health interventions. Please see later in the article for the Editors' Summary PMID:22719233

  16. A multifaceted intervention to improve the quality of care of children in district hospitals in Kenya: a cost-effectiveness analysis.

    PubMed

    Barasa, Edwine W; Ayieko, Philip; Cleary, Susan; English, Mike

    2012-01-01

    To improve care for children in district hospitals in Kenya, a multifaceted approach employing guidelines, training, supervision, feedback, and facilitation was developed, for brevity called the Emergency Triage and Treatment Plus (ETAT+) strategy. We assessed the cost effectiveness of the ETAT+ strategy, in Kenyan hospitals. Further, we estimate the costs of scaling up the intervention to Kenya nationally and potential cost effectiveness at scale. Our cost-effectiveness analysis from the provider's perspective used data from a previously reported cluster randomized trial comparing the full ETAT+ strategy (n = 4 hospitals) with a partial intervention (n = 4 hospitals). Effectiveness was measured using 14 process measures that capture improvements in quality of care; their average was used as a summary measure of quality. Economic costs of the development and implementation of the intervention were determined (2009 US$). Incremental cost-effectiveness ratios were defined as the incremental cost per percentage improvement in (average) quality of care. Probabilistic sensitivity analysis was used to assess uncertainty. The cost per child admission was US$50.74 (95% CI 49.26-67.06) in intervention hospitals compared to US$31.1 (95% CI 30.67-47.18) in control hospitals. Each percentage improvement in average quality of care cost an additional US$0.79 (95% CI 0.19-2.31) per admitted child. The estimated annual cost of nationally scaling up the full intervention was US$3.6 million, approximately 0.6% of the annual child health budget in Kenya. A "what-if" analysis assuming conservative reductions in mortality suggests the incremental cost per disability adjusted life year (DALY) averted by scaling up would vary between US$39.8 and US$398.3. Improving quality of care at scale nationally with the full ETAT+ strategy may be affordable for low income countries such as Kenya. Resultant plausible reductions in hospital mortality suggest the intervention could be cost-effective when compared to incremental cost-effectiveness ratios of other priority child health interventions.

  17. 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.

  18. The effect of fault-bend folding on seismic velocity in the marginal ridge of accretionary prisms

    USGS Publications Warehouse

    Cai, Y.; Wang, Chun-Yong; Hwang, W.-t.; Cochrane, G.R.

    1995-01-01

    Fluid venting in accretionary prisms, which feeds chemosynthetic biological communities, occurs mostly on the marginal thrust ridge. New seismic data for the marginal ridge of the Cascadia prism show significantly lower velocity than that in the adjacent oceanic basin and place important constraints on the interpretations of why fluid venting occurs mostly on the marginal ridge. We employed a finite-element method to analyze a typical fault-bend folding model to explain the phenomenon. The fault in the model is simulated by contact elements. The elements are characterized not only by finite sliding along a slide line, but also by elastoplastic deformation. We present the results of a stress analysis which show that the marginal ridge is under subhorizontal extension and the frontal thrust is under compression. This state of stress favors the growth of tensile cracks in the marginal ridge, facilitates fluid flow and reduces seismic velocities therein; on the other hand, it may close fluid pathways along the frontal thrust and divert fluid flow to the marginal ridge. ?? 1995 Birkha??user Verlag.

  19. 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).

  20. Relationship of Automobile Characteristics to List Prices and Profit Margins -- A Preliminary Analysis

    DOT National Transportation Integrated Search

    1978-08-01

    The report describes research on potential impacts of fuel economy regulations on the U.S. automobile industry. The study focused on the possible effects of auto "down-sizing" on manufacture profit margins. Historical price data were used to estimate...

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