Science.gov

Sample records for conversion factor analysis

  1. Nominal Performance Biosphere Dose Conversion Factor Analysis

    SciTech Connect

    M. Wasiolek

    2004-09-08

    This analysis report is one of the technical reports containing documentation of the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), a biosphere model supporting the Total System Performance Assessment (TSPA) for the license application (LA) for the Yucca Mountain repository. This analysis report describes the development of biosphere dose conversion factors (BDCFs) for the groundwater exposure scenario, and the development of conversion factors for assessing compliance with the groundwater protection standard. A graphical representation of the documentation hierarchy for the ERMYN is presented in Figure 1-1. This figure shows the interrelationships among the products (i.e., analysis and model reports) developed for biosphere modeling and provides an understanding of how this analysis report contributes to biosphere modeling. This report is one of two reports that develop biosphere BDCFs, which are input parameters for the TSPA-LA model. The ''Biosphere Model Report'' (BSC 2004 [DIRS 169460]) describes in detail the ERMYN conceptual model and mathematical model. The input parameter reports, shown to the right of the ''Biosphere Model Report'' in Figure 1-1, contain detailed description of the model input parameters, their development, and the relationship between the parameters and specific features events and processes (FEPs). This report describes biosphere model calculations and their output, the BDCFs, for the groundwater exposure scenario. The objectives of this analysis are to develop BDCFs for the groundwater exposure scenario for the three climate states considered in the TSPA-LA as well as conversion factors for evaluating compliance with the groundwater protection standard. The BDCFs will be used in performance assessment for calculating all-pathway annual doses for a given concentration of radionuclides in groundwater. The conversion factors will be used for calculating gross alpha particle activity in groundwater and the annual dose

  2. Nominal Performance Biosphere Dose Conversion Factor Analysis

    SciTech Connect

    M.A. Wasiolek

    2003-07-25

    This analysis report is one of the technical reports containing documentation of the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), a biosphere model supporting the Total System Performance Assessment (TSPA) for the license application (LA) for the Yucca Mountain repository. This analysis report describes the development of biosphere dose conversion factors (BDCFs) for the groundwater exposure scenario, and the development of conversion factors for assessing compliance with the groundwater protection standard. A graphical representation of the documentation hierarchy for the ERMYN is presented in Figure 1-1. This figure shows the interrelationships among the products (i.e., analysis and model reports) developed for biosphere modeling and provides an understanding of how this analysis report contributes to biosphere modeling. This report is one of two reports that develop biosphere BDCFs, which are input parameters for the TSPA model. The ''Biosphere Model Report'' (BSC 2003 [DIRS 164186]) describes in detail the ERMYN conceptual model and mathematical model. The input parameter reports (BSC 2003 [DIRS 160964]; BSC 2003 [DIRS 160965]; BSC 2003 [DIRS 160976]; BSC 2003 [DIRS 161239]; BSC 2003 [DIRS 161241]) contain detailed description of the model input parameters. This report describes biosphere model calculations and their output, the BDCFs, for the groundwater exposure scenario. The objectives of this analysis are to develop BDCFs and conversion factors for the TSPA. The BDCFs will be used in performance assessment for calculating annual doses for a given concentration of radionuclides in groundwater. The conversion factors will be used for calculating gross alpha particle activity in groundwater and the annual dose from beta- and photon-emitting radionuclides.

  3. Nominal Performance Biosphere Dose Conversion Factor Analysis

    SciTech Connect

    M.A. Wasiolek

    2005-04-28

    This analysis report is one of the technical reports containing documentation of the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), a biosphere model supporting the Total System Performance Assessment (TSPA) for the license application (LA) for the Yucca Mountain repository. This analysis report describes the development of biosphere dose conversion factors (BDCFs) for the groundwater exposure scenario, and the development of conversion factors for assessing compliance with the groundwater protection standards. A graphical representation of the documentation hierarchy for the ERMYN is presented in Figure 1-1. This figure shows the interrelationships among the products (i.e., analysis and model reports) developed for biosphere modeling and provides an understanding of how this analysis report contributes to biosphere modeling. This report is one of two reports that develop BDCFs, which are input parameters for the TSPA-LA model. The ''Biosphere Model Report'' (BSC 2004 [DIRS 169460]) describes in detail the ERMYN conceptual model and mathematical model. The input parameter reports, shown to the right of the ''Biosphere Model Report'' in Figure 1-1, contain detailed description of the model input parameters, their development, and the relationship between the parameters and specific features events and processes (FEPs). This report describes biosphere model calculations and their output, the BDCFs, for the groundwater exposure scenario. This analysis receives direct input from the outputs of the ''Biosphere Model Report'' (BSC 2004 [DIRS 169460]) and the five analyses that develop parameter values for the biosphere model (BSC 2005 [DIRS 172827]; BSC 2004 [DIRS 169672]; BSC 2004 [DIRS 169673]; BSC 2004 [DIRS 169458]; BSC 2004 [DIRS 169459]). The results of this report are further analyzed in the ''Biosphere Dose Conversion Factor Importance and Sensitivity Analysis'' (Figure 1-1). The objectives of this analysis are to develop BDCFs for the

  4. Disruptive Event Biosphere Dose Conversion Factor Analysis

    SciTech Connect

    M. A. Wasiolek

    2003-07-21

    This analysis report, ''Disruptive Event Biosphere Dose Conversion Factor Analysis'', is one of the technical reports containing documentation of the ERMYN (Environmental Radiation Model for Yucca Mountain Nevada) biosphere model for the geologic repository at Yucca Mountain, its input parameters, and the application of the model to perform the dose assessment for the repository. The biosphere model is one of a series of process models supporting the Total System Performance Assessment (TSPA) for the Yucca Mountain repository. A graphical representation of the documentation hierarchy for the ERMYN is presented in Figure 1-1. This figure shows the interrelationships among the products (i.e., analysis and model reports) developed for biosphere modeling and provides an understanding of how this analysis report contributes to biosphere modeling. This report is one of the two reports that develop biosphere dose conversion factors (BDCFs), which are input parameters for the TSPA model. The ''Biosphere Model Report'' (BSC 2003 [DIRS 164186]) describes in detail the conceptual model as well as the mathematical model and lists its input parameters. Model input parameters are developed and described in detail in five analysis report (BSC 2003 [DIRS 160964], BSC 2003 [DIRS 160965], BSC 2003 [DIRS 160976], BSC 2003 [DIRS 161239], and BSC 2003 [DIRS 161241]). The objective of this analysis was to develop the BDCFs for the volcanic ash exposure scenario and the dose factors (DFs) for calculating inhalation doses during volcanic eruption (eruption phase of the volcanic event). The volcanic ash exposure scenario is hereafter referred to as the volcanic ash scenario. For the volcanic ash scenario, the mode of radionuclide release into the biosphere is a volcanic eruption through the repository with the resulting entrainment of contaminated waste in the tephra and the subsequent atmospheric transport and dispersion of contaminated material in the biosphere. The biosphere process

  5. Disruptive Event Biosphere Dose Conversion Factor Analysis

    SciTech Connect

    M. Wasiolek

    2004-09-08

    This analysis report is one of the technical reports containing documentation of the Environmental Radiation Model for Yucca Mountain, Nevada (ERMYN), a biosphere model supporting the total system performance assessment (TSPA) for the license application (LA) for the Yucca Mountain repository. This analysis report describes the development of biosphere dose conversion factors (BDCFs) for the volcanic ash exposure scenario, and the development of dose factors for calculating inhalation dose during volcanic eruption. A graphical representation of the documentation hierarchy for the ERMYN is presented in Figure 1-1. This figure shows the interrelationships among the products (i.e., analysis and model reports) developed for biosphere modeling and provides an understanding of how this analysis report contributes to biosphere modeling. This report is one of two reports that develop biosphere BDCFs, which are input parameters for the TSPA model. The ''Biosphere Model Report'' (BSC 2004 [DIRS 169460]) describes in detail the ERMYN conceptual model and mathematical model. The input parameter reports, shown to the right of the Biosphere Model Report in Figure 1-1, contain detailed descriptions of the model input parameters, their development and the relationship between the parameters and specific features, events and processes (FEPs). This report describes biosphere model calculations and their output, the BDCFs, for the volcanic ash exposure scenario. This analysis receives direct input from the outputs of the ''Biosphere Model Report'' (BSC 2004 [DIRS 169460]) and from the five analyses that develop parameter values for the biosphere model (BSC 2004 [DIRS 169671]; BSC 2004 [DIRS 169672]; BSC 2004 [DIRS 169673]; BSC 2004 [DIRS 169458]; and BSC 2004 [DIRS 169459]). The results of this report are further analyzed in the ''Biosphere Dose Conversion Factor Importance and Sensitivity Analysis''. The objective of this analysis was to develop the BDCFs for the volcanic ash

  6. Disruptive Event Biosphere Doser Conversion Factor Analysis

    SciTech Connect

    M. Wasiolek

    2000-12-28

    The purpose of this report was to document the process leading to, and the results of, development of radionuclide-, exposure scenario-, and ash thickness-specific Biosphere Dose Conversion Factors (BDCFs) for the postulated postclosure extrusive igneous event (volcanic eruption) at Yucca Mountain. BDCF calculations were done for seventeen radionuclides. The selection of radionuclides included those that may be significant dose contributors during the compliance period of up to 10,000 years, as well as radionuclides of importance for up to 1 million years postclosure. The approach documented in this report takes into account human exposure during three different phases at the time of, and after, volcanic eruption. Calculations of disruptive event BDCFs used the GENII-S computer code in a series of probabilistic realizations to propagate the uncertainties of input parameters into the output. The pathway analysis included consideration of different exposure pathway's contribution to the BDCFs. BDCFs for volcanic eruption, when combined with the concentration of radioactivity deposited by eruption on the soil surface, allow calculation of potential radiation doses to the receptor of interest. Calculation of radioactivity deposition is outside the scope of this report and so is the transport of contaminated ash from the volcano to the location of the receptor. The integration of the biosphere modeling results (BDCFs) with the outcomes of the other component models is accomplished in the Total System Performance Assessment (TSPA), in which doses are calculated to the receptor of interest from radionuclides postulated to be released to the environment from the potential repository at Yucca Mountain.

  7. Nominal Performance Biosphere Dose Conversion Factor Analysis

    SciTech Connect

    Wasiolek, Maryla A.

    2000-12-21

    The purpose of this report was to document the process leading to development of the Biosphere Dose Conversion Factors (BDCFs) for the postclosure nominal performance of the potential repository at Yucca Mountain. BDCF calculations concerned twenty-four radionuclides. This selection included sixteen radionuclides that may be significant nominal performance dose contributors during the compliance period of up to 10,000 years, five additional radionuclides of importance for up to 1 million years postclosure, and three relatively short-lived radionuclides important for the human intrusion scenario. Consideration of radionuclide buildup in soil caused by previous irrigation with contaminated groundwater was taken into account in the BDCF development. The effect of climate evolution, from the current arid conditions to a wetter and cooler climate, on the BDCF values was evaluated. The analysis included consideration of different exposure pathway's contribution to the BDCFs. Calculations of nominal performance BDCFs used the GENII-S computer code in a series of probabilistic realizations to propagate the uncertainties of input parameters into the output. BDCFs for the nominal performance, when combined with the concentrations of radionuclides in groundwater allow calculation of potential radiation doses to the receptor of interest. Calculated estimates of radionuclide concentration in groundwater result from the saturated zone modeling. The integration of the biosphere modeling results (BDCFs) with the outcomes of the other component models is accomplished in the Total System Performance Assessment (TSPA) to calculate doses to the receptor of interest from radionuclides postulated to be released to the environment from the potential repository at Yucca Mountain.

  8. Biosphere dose conversion Factor Importance and Sensitivity Analysis

    SciTech Connect

    M. Wasiolek

    2004-10-15

    This report presents importance and sensitivity analysis for the environmental radiation model for Yucca Mountain, Nevada (ERMYN). ERMYN is a biosphere model supporting the total system performance assessment (TSPA) for the license application (LA) for the Yucca Mountain repository. This analysis concerns the output of the model, biosphere dose conversion factors (BDCFs) for the groundwater, and the volcanic ash exposure scenarios. It identifies important processes and parameters that influence the BDCF values and distributions, enhances understanding of the relative importance of the physical and environmental processes on the outcome of the biosphere model, includes a detailed pathway analysis for key radionuclides, and evaluates the appropriateness of selected parameter values that are not site-specific or have large uncertainty.

  9. Common conversion factors.

    PubMed

    2001-05-01

    This appendix presents tables of some of the more common conversion factors for units of measure used throughout Current Protocols manuals, as well as prefixes indicating powers of ten for SI units. Another table gives conversions between temperatures on the Celsius (Centigrade) and Fahrenheit scales. PMID:18770653

  10. A meta-analysis of responses of canopy photosynthetic conversion efficiency to environmental factors reveal major causes of yield gap

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Improving plant energy conversion efficiency is crucial for increasing food and bioenergy crop production and yields. This study statistically quantifies the effects of climate/weather factors and management techniques on energy conversion efficiency from 140 published studies and provides a quantit...

  11. 42 CFR 414.28 - Conversion factors.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 3 2014-10-01 2014-10-01 false Conversion factors. 414.28 Section 414.28 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICARE PROGRAM (CONTINUED) PAYMENT FOR PART B MEDICAL AND OTHER HEALTH SERVICES Physicians and Other Practitioners § 414.28 Conversion factors....

  12. Technique for measuring gas conversion factors

    NASA Technical Reports Server (NTRS)

    Singh, J. J.; Sprinkle, D. R. (Inventor)

    1985-01-01

    A method for determining hydrocarbon conversion factors for a flowmeter. A mixture of air, O2 and C sub x H sub y is burned and the partial paressure of O2 in the resulting gas is forced to equal the partial pressure of O2 in air. The flowrate of O2 flowing into the mixture is measured by flowmeter and the flowrate of C sub x H sub y flowing into the mixture is measured by the flowmeter conversion factor is to be determined. These measured values are used to calculate the conversion factor.

  13. 42 CFR 414.28 - Conversion factors.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 3 2011-10-01 2011-10-01 false Conversion factors. 414.28 Section 414.28 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICARE PROGRAM PAYMENT FOR PART B MEDICAL AND OTHER HEALTH SERVICES Physicians and Other...

  14. 42 CFR 414.28 - Conversion factors.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 3 2012-10-01 2012-10-01 false Conversion factors. 414.28 Section 414.28 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICARE PROGRAM (CONTINUED) PAYMENT FOR PART B MEDICAL AND OTHER HEALTH SERVICES Physicians and...

  15. 42 CFR 414.28 - Conversion factors.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 3 2010-10-01 2010-10-01 false Conversion factors. 414.28 Section 414.28 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICARE PROGRAM PAYMENT FOR PART B MEDICAL AND OTHER HEALTH SERVICES Physicians and Other...

  16. 42 CFR 414.28 - Conversion factors.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 3 2013-10-01 2013-10-01 false Conversion factors. 414.28 Section 414.28 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICARE PROGRAM (CONTINUED) PAYMENT FOR PART B MEDICAL AND OTHER HEALTH SERVICES Physicians and...

  17. Derivation of dose conversion factors for tritium

    SciTech Connect

    Killough, G. G.

    1982-03-01

    For a given intake mode (ingestion, inhalation, absorption through the skin), a dose conversion factor (DCF) is the committed dose equivalent to a specified organ of an individual per unit intake of a radionuclide. One also may consider the effective dose commitment per unit intake, which is a weighted average of organ-specific DCFs, with weights proportional to risks associated with stochastic radiation-induced fatal health effects, as defined by Publication 26 of the International Commission on Radiological Protection (ICRP). This report derives and tabulates organ-specific dose conversion factors and the effective dose commitment per unit intake of tritium. These factors are based on a steady-state model of hydrogen in the tissues of ICRP's Reference Man (ICRP Publication 23) and equilibrium of specific activities between body water and other tissues. The results differ by 27 to 33% from the estimate on which ICRP Publication 30 recommendations are based. The report also examines a dynamic model of tritium retention in body water, mineral bone, and two compartments representing organically-bound hydrogen. This model is compared with data from human subjects who were observed for extended periods. The manner of combining the dose conversion factors with measured or model-predicted levels of contamination in man's exposure media (air, drinking water, soil moisture) to estimate dose rate to an individual is briefly discussed.

  18. Conversion from robotic surgery to laparotomy: A case-control study evaluating risk factors for conversion

    PubMed Central

    Jones, Nate; Fleming, Nicole D.; Nick, Alpa M.; Munsell, Mark F.; Rallapalli, Vijayashri; Westin, Shannon N.; Meyer, Larissa A.; Schmeler, Kathleen M.; Ramirez, Pedro T.; Soliman, Pamela T.

    2014-01-01

    Objectives To determine risk factors associated with conversion to laparotomy for women undergoing robotic gynecologic surgery. Methods The medical records of 459 consecutive robotic surgery cases performed between December 2006 and October 2011 by 8 different surgeons at a single institution were retrospectively reviewed. Cases converted to laparotomy were compared to those completed robotically. Descriptive statistics were used to summarize the demographic and clinical characteristics. Results Forty of 459 (8.7%, 95% CI 6.3%-11.7%) patients had conversion to open surgery. Reason for conversion included poor visualization due to adhesions (13), inability to tolerate Trendelenburg (7), enlarged uterus (7), extensive peritoneal disease (5), bowel injury (2), ureteral injury (1), vascular injury (1), bladder injury (1), technical difficulty with the robot (2), and inability to access abdominal cavity (1). 5% of cases were converted prior to docking the robot. On univariate analysis preoperative diagnosis (p=0.012), non-White race (p=0.004), history of asthma (p=0.027), ASA score (p=0.032), bowel injury (p=0.012), greater BMI (p<0.001), need for blood transfusion (p<0.001), and expected blood loss (p<0.001) were associated with conversion. On multivariate analysis, non-White race (OR 2.88, 95% CI 1.39-5.96, p=0.004), bowel injury (OR 35.40, 95% CI 3.00-417.28, p=0.005), and increasing BMI (OR 1.06, 95% CI 1.03-1.09, p<0.001) were significantly associated with increased risk for conversion. Prior surgery was not associated with conversion to open surgery (p=0.347). Conclusion Conversion to laparotomy was required for 8.7% of patients undergoing robotic surgery for a gynecologic indication. Increasing BMI and non-white race were identified as the two preoperative risk factors associated with conversion. PMID:24937481

  19. 7 CFR 989.601 - Conversion factors for raisin weight.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 8 2013-01-01 2013-01-01 false Conversion factors for raisin weight. 989.601 Section... SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE RAISINS PRODUCED FROM GRAPES GROWN IN CALIFORNIA Conversion Factors § 989.601 Conversion factors for raisin...

  20. 7 CFR 989.601 - Conversion factors for raisin weight.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 8 2012-01-01 2012-01-01 false Conversion factors for raisin weight. 989.601 Section... SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE RAISINS PRODUCED FROM GRAPES GROWN IN CALIFORNIA Conversion Factors § 989.601 Conversion factors for raisin...

  1. 7 CFR 989.601 - Conversion factors for raisin weight.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 8 2014-01-01 2014-01-01 false Conversion factors for raisin weight. 989.601 Section... SERVICE (MARKETING AGREEMENTS AND ORDERS; FRUITS, VEGETABLES, NUTS), DEPARTMENT OF AGRICULTURE RAISINS PRODUCED FROM GRAPES GROWN IN CALIFORNIA Conversion Factors § 989.601 Conversion factors for raisin...

  2. Drivers of Wetland Conversion: a Global Meta-Analysis

    PubMed Central

    van Asselen, Sanneke; Verburg, Peter H.; Vermaat, Jan E.; Janse, Jan H.

    2013-01-01

    Meta-analysis of case studies has become an important tool for synthesizing case study findings in land change. Meta-analyses of deforestation, urbanization, desertification and change in shifting cultivation systems have been published. This present study adds to this literature, with an analysis of the proximate causes and underlying forces of wetland conversion at a global scale using two complementary approaches of systematic review. Firstly, a meta-analysis of 105 case-study papers describing wetland conversion was performed, showing that different combinations of multiple-factor proximate causes, and underlying forces, drive wetland conversion. Agricultural development has been the main proximate cause of wetland conversion, and economic growth and population density are the most frequently identified underlying forces. Secondly, to add a more quantitative component to the study, a logistic meta-regression analysis was performed to estimate the likelihood of wetland conversion worldwide, using globally-consistent biophysical and socioeconomic location factor maps. Significant factors explaining wetland conversion, in order of importance, are market influence, total wetland area (lower conversion probability), mean annual temperature and cropland or built-up area. The regression analyses results support the outcomes of the meta-analysis of the processes of conversion mentioned in the individual case studies. In other meta-analyses of land change, similar factors (e.g., agricultural development, population growth, market/economic factors) are also identified as important causes of various types of land change (e.g., deforestation, desertification). Meta-analysis helps to identify commonalities across the various local case studies and identify which variables may lead to individual cases to behave differently. The meta-regression provides maps indicating the likelihood of wetland conversion worldwide based on the location factors that have determined historic

  3. Analysis of internal conversion coefficients

    PubMed

    Coursol; Gorozhankin; Yakushev; Briancon; Vylov

    2000-03-01

    An extensive database has been assembled that contains the three most widely used sets of calculated internal conversion coefficients (ICC): [Hager R.S., Seltzer E.C., 1968. Internal conversion tables. K-, L-, M-shell Conversion coefficients for Z = 30 to Z = 103, Nucl. Data Tables A4, 1-237; Band I.M., Trzhaskovskaya M.B., 1978. Tables of gamma-ray internal conversion coefficients for the K-, L- and M-shells, 10 < or = Z < or = 104, Special Report of Leningrad Nuclear Physics Institute; Rosel F., Fries H.M., Alder K., Pauli H.C., 1978. Internal conversion coefficients for all atomic shells, At. Data Nucl. Data Tables 21, 91-289] and also includes new Dirac Fock calculations [Band I.M. and Trzhaskovskaya M.B., 1993. Internal conversion coefficients for low-energy nuclear transitions, At. Data Nucl. Data Tables 55, 43-61]. This database is linked to a computer program to plot ICCs and their combinations (sums and ratios) as a function of Z and energy, as well as relative deviations of ICC or their combinations for any pair of tabulated data. Examples of these analyses are presented for the K-shell and total ICCs of the gamma-ray standards [Hansen H.H., 1985. Evaluation of K-shell and total internal conversion coefficients for some selected nuclear transitions, Eur. Appl. Res. Rept. Nucl. Sci. Tech. 11.6 (4) 777-816] and for the K-shell and total ICCs of high multipolarity transitions (total, K-, L-, M-shells of E3 and M3 and K-shell of M4). Experimental data sets are also compared with the theoretical values of these specific calculations. PMID:10724406

  4. Psychosocial Factors in Children and Adolescents with Conversion Disorder

    ERIC Educational Resources Information Center

    Sharma, I.; Giri, D.; Dutta, Anna; Mazumder, P.

    2005-01-01

    Introduction: In view of the limited studies on the psychosocial environment of children presenting with conversion disorders, the present study was carried out to study the psychosocial factors in children with conversion disorders. Method: 40 patients of Conversion Disorder, who presented with "pseudo seizures" and were diagnosed according to…

  5. Gene array analysis of neural crest cells identifies transcription factors necessary for direct conversion of embryonic fibroblasts into neural crest cells

    PubMed Central

    Motohashi, Tsutomu; Watanabe, Natsuki; Nishioka, Masahiro; Nakatake, Yuhki; Yulan, Piao; Mochizuki, Hiromi; Kawamura, Yoshifumi; Ko, Minoru S. H.; Goshima, Naoki; Kunisada, Takahiro

    2016-01-01

    ABSTRACT Neural crest cells (NC cells) are multipotent cells that emerge from the edge of the neural folds and migrate throughout the developing embryo. Although the gene regulatory network for generation of NC cells has been elucidated in detail, it has not been revealed which of the factors in the network are pivotal to directing NC identity. In this study we analyzed the gene expression profile of a pure NC subpopulation isolated from Sox10-IRES-Venus mice and investigated whether these genes played a key role in the direct conversion of Sox10-IRES-Venus mouse embryonic fibroblasts (MEFs) into NC cells. The comparative molecular profiles of NC cells and neural tube cells in 9.5-day embryos revealed genes including transcription factors selectively expressed in developing trunk NC cells. Among 25 NC cell-specific transcription factor genes tested, SOX10 and SOX9 were capable of converting MEFs into SOX10-positive (SOX10+) cells. The SOX10+ cells were then shown to differentiate into neurons, glial cells, smooth muscle cells, adipocytes and osteoblasts. These SOX10+ cells also showed limited self-renewal ability, suggesting that SOX10 and SOX9 directly converted MEFs into NC cells. Conversely, the remaining transcription factors, including well-known NC cell specifiers, were unable to convert MEFs into SOX10+ NC cells. These results suggest that SOX10 and SOX9 are the key factors necessary for the direct conversion of MEFs into NC cells. PMID:26873953

  6. Gene array analysis of neural crest cells identifies transcription factors necessary for direct conversion of embryonic fibroblasts into neural crest cells.

    PubMed

    Motohashi, Tsutomu; Watanabe, Natsuki; Nishioka, Masahiro; Nakatake, Yuhki; Yulan, Piao; Mochizuki, Hiromi; Kawamura, Yoshifumi; Ko, Minoru S H; Goshima, Naoki; Kunisada, Takahiro

    2016-01-01

    Neural crest cells (NC cells) are multipotent cells that emerge from the edge of the neural folds and migrate throughout the developing embryo. Although the gene regulatory network for generation of NC cells has been elucidated in detail, it has not been revealed which of the factors in the network are pivotal to directing NC identity. In this study we analyzed the gene expression profile of a pure NC subpopulation isolated from Sox10-IRES-Venus mice and investigated whether these genes played a key role in the direct conversion of Sox10-IRES-Venus mouse embryonic fibroblasts (MEFs) into NC cells. The comparative molecular profiles of NC cells and neural tube cells in 9.5-day embryos revealed genes including transcription factors selectively expressed in developing trunk NC cells. Among 25 NC cell-specific transcription factor genes tested, SOX10 and SOX9 were capable of converting MEFs into SOX10-positive (SOX10+) cells. The SOX10+ cells were then shown to differentiate into neurons, glial cells, smooth muscle cells, adipocytes and osteoblasts. These SOX10+ cells also showed limited self-renewal ability, suggesting that SOX10 and SOX9 directly converted MEFs into NC cells. Conversely, the remaining transcription factors, including well-known NC cell specifiers, were unable to convert MEFs into SOX10+ NC cells. These results suggest that SOX10 and SOX9 are the key factors necessary for the direct conversion of MEFs into NC cells. PMID:26873953

  7. Laser power conversion system analysis

    NASA Technical Reports Server (NTRS)

    1982-01-01

    Orbit to orbit and orbit to ground laser power conversion systems and power transfer are discussed. A system overview is presented. Pilot program parameters are considered: SLPS assumptions are listed, a laser SPS overview is presented, specifications are listed, and SLPS coats are considered.

  8. Doing Conversation Analysis: A Practical Guide.

    ERIC Educational Resources Information Center

    ten Have, Paul

    Noting that conversation analysis (CA) has developed into one of the major methods of analyzing speech in the disciplines of communications, linguistics, anthropology and sociology, this book demonstrates in a practical way how to become a conversation analyst. As well as providing an overall introduction to the approach, it focuses on the…

  9. 42 CFR 414.30 - Conversion factor update.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 42 Public Health 3 2013-10-01 2013-10-01 false Conversion factor update. 414.30 Section 414.30 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Other Practitioners § 414.30 Conversion factor update. Unless Congress acts in accordance with...

  10. 42 CFR 414.30 - Conversion factor update.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 42 Public Health 3 2011-10-01 2011-10-01 false Conversion factor update. 414.30 Section 414.30 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Practitioners § 414.30 Conversion factor update. Unless Congress acts in accordance with section 1848(d)(3)...

  11. 42 CFR 414.30 - Conversion factor update.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 42 Public Health 3 2012-10-01 2012-10-01 false Conversion factor update. 414.30 Section 414.30 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES... Other Practitioners § 414.30 Conversion factor update. Unless Congress acts in accordance with...

  12. Ethnomethodology, Conversation Analysis and Education: An Overview.

    ERIC Educational Resources Information Center

    Watson, D. Rodney

    1992-01-01

    Considers the applicability of ethnomethodology and conversation analysis (which focus on language and the social organization of linguistic interchange) to the study of education, children's techniques of communication, socialization processes, and classroom communication. (DMM)

  13. 42 CFR 414.30 - Conversion factor update.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 42 Public Health 3 2014-10-01 2014-10-01 false Conversion factor update. 414.30 Section 414.30 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICARE PROGRAM (CONTINUED) PAYMENT FOR PART B MEDICAL AND OTHER HEALTH SERVICES Physicians and Other Practitioners § 414.30 Conversion...

  14. Laser power conversion system analysis, volume 1

    NASA Technical Reports Server (NTRS)

    Jones, W. S.; Morgan, L. L.; Forsyth, J. B.; Skratt, J. P.

    1979-01-01

    The orbit-to-orbit laser energy conversion system analysis established a mission model of satellites with various orbital parameters and average electrical power requirements ranging from 1 to 300 kW. The system analysis evaluated various conversion techniques, power system deployment parameters, power system electrical supplies and other critical supplies and other critical subsystems relative to various combinations of the mission model. The analysis show that the laser power system would not be competitive with current satellite power systems from weight, cost and development risk standpoints.

  15. Hollywood's Conversion to Color: The Technological, Economic and Aesthetic Factors.

    ERIC Educational Resources Information Center

    Kindem, Forham A.

    1979-01-01

    Discusses the film industry's conversion to color cinematography in the period between the 1920s and 1960s. Cites economic considerations, technological modifications, and aesthetic preferences by audiences as factors in this development. (JMF)

  16. A Pattern Analysis of Gene Conversion Literature

    PubMed Central

    Lawson, Mark J.; Jiao, Jian; Fan, Weiguo; Zhang, Liqing

    2009-01-01

    Gene conversion is an important biological process that involves the transfer of genetic (sequence) information from one gene to another. This can have a variety of effects on an organism, both short-term and long-term and both positive and detrimental. In an effort to better understand this process, we searched through over 3,000 abstracts that contain research on gene conversions, tagging the important data and performing an analysis on what we extract. Through this we established trends that give a better insight into gene conversion research and genetic research in general. Our results show the importance of the process and the importance of continuing gene conversion research. PMID:20148076

  17. Laser power conversion system analysis, volume 2

    NASA Technical Reports Server (NTRS)

    Jones, W. S.; Morgan, L. L.; Forsyth, J. B.; Skratt, J. P.

    1979-01-01

    The orbit-to-ground laser power conversion system analysis investigated the feasibility and cost effectiveness of converting solar energy into laser energy in space, and transmitting the laser energy to earth for conversion to electrical energy. The analysis included space laser systems with electrical outputs on the ground ranging from 100 to 10,000 MW. The space laser power system was shown to be feasible and a viable alternate to the microwave solar power satellite. The narrow laser beam provides many options and alternatives not attainable with a microwave beam.

  18. Incidence of cesarean section and analysis of risk factors for failed conversion of labor epidural to surgical anesthesia: A prospective, observational study in a tertiary care center

    PubMed Central

    Ismail, Samina; Chugtai, Shakaib; Hussain, Alia

    2015-01-01

    Background and Aims: This study aimed to analyze the effect of labor epidural (LE) on the incidence of cesarean section (CS) and assess the risk factors involved in failed conversion of LE to surgical anesthesia for CS. Material and Methods: A prospective observational study of 18 months from January 2012 to June 2013 was conducted on all patients who had delivered in the labor room suit of our hospital. The data collected for all 4694 patients included their demographics, parity and mode of delivery. In addition a predesigned proforma, with additional information was used for 629 parturient with LE. Results: During the study period, total numbers of deliveries performed in our hospital were 4694, with an epidural rate of 13.4% (629/4694). No significant difference (P = 0.06) was observed in the rate of CS among women with or without LE (28 % [n = 176/629] vs. 31.7 % [n = 1289/4065]), however, a statistically significant difference (P < 0.01) was observed in the rate of assisted delivery in patients receiving LE as compared to those delivering without it (8.7% [n = 55/629] vs. n = 3.7% [154/4065]). For 176 patients requiring CS, LE utilization for surgical anesthesia was 52.8% (93/176) and factors identified for not utilizing LE in 47% (83/176) were; failure to achieve surgical anesthesia in 6.8% (12/176), emergency CS in 28.4% (50/176), patient preference in 6.8% (12/176) and inadequate labor pain relief with LE in 5.1% (9/176) patients. Non-obstetric anesthesiologists were involved in 59% (49/83) of cases where LE was not used for CS. Conclusion: LE had no effect on the rate of CS; however it significantly increased (P < 0.01) the rate of assisted delivery. Factors like inadequate LE, emergency situations and non-obstetric anesthesiologists can all be responsible for failed conversion of LE to surgical anesthesia for CS. PMID:26702215

  19. 7 CFR 989.601 - Conversion factors for raisin weight.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 8 2010-01-01 2010-01-01 false Conversion factors for raisin weight. 989.601 Section 989.601 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE RAISINS PRODUCED FROM GRAPES GROWN IN...

  20. 7 CFR 989.601 - Conversion factors for raisin weight.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 8 2011-01-01 2011-01-01 false Conversion factors for raisin weight. 989.601 Section 989.601 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Marketing Agreements and Orders; Fruits, Vegetables, Nuts), DEPARTMENT OF AGRICULTURE RAISINS PRODUCED FROM GRAPES GROWN IN...

  1. Shelflist Conversion at NCSU: Factors in Decision Making.

    ERIC Educational Resources Information Center

    Davis, Jinnie Y.

    Written when an in-house retrospective conversion project on the monographs collection of an academic library was 80% complete, this paper presents factors for consideration by decision-makers prior to establishing a similar project. Topics considered together with a description of how North Carolina State University (NCSU) handled each, include:…

  2. Conversion during thoracoscopic lobectomy: related factors and learning curve impact.

    PubMed

    Smith, David E; Dietrich, Agustin; Nicolas, Matias; Da Lozzo, Alejandro; Beveraggi, Enrique

    2015-12-01

    Video-assisted thoracoscopic surgery (VATS) lobectomy has become a standard procedure for lung cancer treatment. Conversion-related factors and learning curve impacts, were poorly described. The aim of this study was to review the reasons and related factor for conversion in VATS lobectomy and the impact on this of the surgeon's learning curve. From June 2009 to May 2014, 154 patients who underwent a VATS lobectomy were included in our study. Patients' characteristics, pathology background, operative times, overall length of stay, overall morbidity and type of major complications were recorded for all patients and compared between non converted (n = 133) and converted (n = 21) patients. To evaluate surgeon's learning curve, we analyzed rates and causes of conversion in the first period (first 77 patients) and in the last period (78-154 patients). Patients characteristics were similar between converted and non-converted groups. Patients who were converted to open thoracotomy presented more frecuently tumors >3 cms (P = 0.02). The average of operative times and the length of stay were not significantly different between groups. Overall morbidity and major complications were also similar in both groups. There were no impact of surgeon's learning curve in overall rate conversion in both groups. Emergency conversion was always secondary to vascular accidents, all in the first group (p = 0.059). Surgeons should be expecting to perform a conversion to a thoracotomy in patients who present in preoperative studies, tumors greater than 3 cms. Learning curve only affected the emergency conversion, occurred all in the first half of our series. PMID:26561493

  3. The CO-to-H2 Conversion Factor

    NASA Astrophysics Data System (ADS)

    Bolatto, Alberto D.; Wolfire, Mark; Leroy, Adam K.

    2013-08-01

    CO line emission represents the most accessible and widely used tracer of the molecular ISM. This renders the translation of observed CO intensity into total H2 gas mass critical to understanding star formation and the ISM in our Galaxy and beyond. We review the theoretical underpinning, techniques, and results of efforts to estimate this CO-to-H2 “conversion factor,” XCO, in different environments. In the Milky Way disk, we recommend a conversion factor of [Formula: see text] cm-2 (K km s-1)-1 with ±30% uncertainty. Studies of other “normal galaxies” return similar values in Milky Way-like disks, but with greater scatter and systematic uncertainty. Departures from this Galactic conversion factor are both observed and expected. Dust-based determinations, theoretical arguments, and scaling relations all suggest that XCO increases with decreasing metallicity, turning up sharply below metallicity ˜1/3-1/2 solar in a manner consistent with model predictions that identify shielding as a key parameter. Based on spectral line modeling and dust observations, XCO appears to drop in the central, bright regions of some but not all galaxies, often coincident with regions of bright CO emission and high stellar surface density. This lower XCO is also present in the overwhelmingly molecular ISM of starburst galaxies, where several lines of evidence point to a lower CO-to-H2 conversion factor. At high redshift, direct evidence regarding the conversion factor remains scarce; we review what is known based on dynamical modeling and other arguments.

  4. Solar Program Assessment: Environmental Factors - Ocean Thermal Energy Conversion.

    ERIC Educational Resources Information Center

    Energy Research and Development Administration, Washington, DC. Div. of Solar Energy.

    This report presents the environmental problems which may arise with the further development of Ocean Thermal Energy Conversion, one of the eight Federally-funded solar technologies. To provide a background for this environmental analysis, the history and basic concepts of the technology are reviewed, as are its economic and resource requirements.…

  5. Reassessment of NRC`s dollar per person-rem conversion factor policy

    SciTech Connect

    1995-12-01

    The US Nuclear Regulatory Commission (NRC) has completed a review and analysis of its dollar per person-rem conversion factor policy. As a result of this review, the NRC has decided to adopt a $2000 per person-rem conversion factor, subject it to present worth considerations, and limit its scope solely to health effects. This is in contrast to the previous policy and staff practice of using an undiscounted $1000 per person-rem conversion factor that served as a surrogate for all offsite consequences (health and offsite property). The policy shift has been incorporated in ``Regulatory Analysis Guidelines of the US Nuclear Regulatory Commission,`` NUREG/BR-0058, Revision 2, November 1995.

  6. Effectiveness Factors and Conversion in a Biocatalytic Membrane Reactor

    PubMed Central

    Godongwana, Buntu

    2016-01-01

    Analytical expressions of the effectiveness factor of a biocatalytic membrane reactor, and its asymptote as the Thiele modulus becomes large, are presented. The evaluation of the effectiveness factor is based on the solution of the governing equations for solute transport in the two regions of the reactor, i.e. the lumen and the matrix (with the biofilm immobilized in the matrix). The lumen solution accounts for both axial diffusion and radial convective flow, while the matrix solution is based on Robin-type boundary conditions. The effectiveness factor is shown to be a function of the Thiele modulus, the partition coefficient, the Sherwood number, the Peclet number, and membrane thickness. Three regions of Thiele moduli are defined in the effectiveness factor graphs. These correspond with reaction rate limited, internal-diffusion limited, and external mass transfer limited solute transport. Radial convective flows were shown to only improve the effectiveness factor in the region of internal diffusion limitation. The assumption of first order kinetics is shown to be applicable only in the Thiele modulus regions of internal and external mass transfer limitation. An iteration scheme is also presented for estimating the effectiveness factor when the solute fractional conversion is known. The model is validated with experimental data from a membrane gradostat reactor immobilised with Phanerochaete chrysosporium for the production of lignin and manganese peroxidases. The developed model and experimental data allow for the determination of the Thiele modulus at which the effectiveness factor and fractional conversion are optimal. PMID:27104954

  7. Risk factors for conversion to conventional laparoscopic cholecystectomy in single incision laparoscopic cholecystectomy

    PubMed Central

    Kim, Sung Gon; Moon, Ju Ik; Lee, Sang Eok; Sung, Nak Song; Chun, Ki Won; Lee, Hye Yoon; Yoon, Dae Sung; Choi, Won Jun

    2016-01-01

    Purpose The aim of this study was to investigate the risk factors for conversion to conventional laparoscopic cholecystectomy (CLC) in single incision laparoscopic cholecystectomy (SILC) along with the proposal for procedure selection guidelines in treating patients with benign gallbladder (GB) diseases. Methods SILC was performed in 697 cases between April 2010 and July 2014. Seventeen cases (2.4%) underwent conversion to conventional LC. We compared these 2 groups and analyzed the risk factors for conversion to CLC. Results In univariate analysis, American Society of Anesthesiologist score > 3, preoperative percutaneous transhepatic GB drainage status and pathology (acute cholecystitis or GB empyema) were significant risk factors for conversion (P = 0.010, P = 0.019 and P < 0.001). In multivariate analysis, pathology (acute cholecystitis or GB empyema) was significant risk factors for conversion to CLC in SILC (P < 0.001). Conclusion Although SILC is a feasible method for most patients with benign GB disease, CLC has to be considered in patients with acute cholecystitis or GB empyema because it is likely to result in inadequate visualization of the Calot's triangle and greater bleeding risk. PMID:27274505

  8. The Exposure Rate Conversion Factor for Nuclear Fallout

    SciTech Connect

    Spriggs, G D

    2009-02-11

    Nuclear fallout is comprised of approximately 2000 radionuclides. About 1000 of these radionuclides are either primary fission products or activated fission products that are created during the burn process. The exposure rate one meter above the surface produced by this complex mixture of radionuclides varies rapidly with time since many of the radionuclides are short-lived and decay numerous times before reaching a stable isotope. As a result, the mixture of radionuclides changes rapidly with time. Using a new code developed at the Lawrence Livermore National Laboratory, the mixture of radionuclides at any given point in time can be calculated. The code also calculates the exposure rate conversion factor (ECF) for all 3864 individual isotopes contained in its database based on the total gamma energy released per decay. Based on the combination of isotope mixture and individual ECFs, the time-dependent variation of the composite exposure rate conversion factor for nuclear fallout can be easily calculated. As example of this new capability, a simple test case corresponding to a 10 kt, uranium-plutonium fuel has been calculated. The results for the time-dependent, composite ECF for this test case are shown in Figure 1. For comparison, we also calculated the composite exposure rate conversion factor using the conversion factors found in Federal Guidance Report No.12 (FGR-12) published by ORNL, which contains the conversion factors for approximately 1000 isotopes. As can be noted from Figure 1, the two functions agree reasonably well at times greater than about 30 minutes. However, they do not agree at early times since FGR-12 does not include all of the short-lived isotopes that are produced in nuclear fallout. It should also be noted that the composite ECF at one hour is 19.7 R/hr per Ci/m{sup 2}. This corresponds to 3148 R/hr per 1 kt per square mile, which agrees reasonably well with the value of 3000 R/hr per 1 kt per square mile as quoted by Glasstone. We have

  9. The Dose Rate Conversion Factors for Nuclear Fallout

    SciTech Connect

    Spriggs, G D

    2009-02-13

    In a previous paper, the composite exposure rate conversion factor (ECF) for nuclear fallout was calculated using a simple theoretical photon-transport model. The theoretical model was used to fill in the gaps in the FGR-12 table generated by ORNL. The FGR-12 table contains the individual conversion factors for approximate 1000 radionuclides. However, in order to calculate the exposure rate during the first 30 minutes following a nuclear detonation, the conversion factors for approximately 2000 radionuclides are needed. From a human-effects standpoint, it is also necessary to have the dose rate conversion factors (DCFs) for all 2000 radionuclides. The DCFs are used to predict the whole-body dose rates that would occur if a human were standing in a radiation field of known exposure rate. As calculated by ORNL, the whole-body dose rate (rem/hr) is approximately 70% of the exposure rate (R/hr) at one meter above the surface. Hence, the individual DCFs could be estimated by multiplying the individual ECFs by 0.7. Although this is a handy rule-of-thumb, a more consistent (and perhaps, more accurate) method of estimating the individual DCFs for the missing radionuclides in the FGR-12 table is to use the linear relationship between DCF and total gamma energy released per decay. This relationship is shown in Figure 1. The DCFs for individual organs in the body can also be estimated from the estimated whole-body DCF. Using the DCFs given FGR-12, the ratio of the organ-specific DCFs to the whole-body DCF were plotted as a function of the whole-body DCF. From these plots, the asymptotic ratios were obtained (see Table 1). Using these asymptotic ratios, the organ-specific DCFs can be estimated using the estimated whole-body DCF for each of the missing radionuclides in the FGR-12 table. Although this procedure for estimating the organ-specific DCFs may over-estimate the value for some low gamma-energy emitters, having a finite value for the organ-specific DCFs in the table is

  10. Calculation of conversion factors for effective dose for various interventional radiology procedures

    SciTech Connect

    Compagnone, Gaetano; Giampalma, Emanuela; Domenichelli, Sara; Renzulli, Matteo; Golfieri, Rita

    2012-05-15

    Purpose: To provide dose-area-product (DAP) to effective dose (E) conversion factors for complete interventional procedures, based on in-the-field clinical measurements of DAP values and using tabulated E/DAP conversion factors for single projections available from the literature. Methods: Nine types of interventional procedures were performed on 84 patients with two angiographic systems. Different calibration curves (with and without patient table attenuation) were calculated for each DAP meter. Clinical and dosimetric parameters were recorded in-the-field for each projection and for all patients, and a conversion factor linking DAP and effective doses was derived for each complete procedure making use of published, Monte Carlo calculated conversion factors for single static projections. Results: Fluoroscopy time and DAP values for the lowest-dose procedure (biliary drainage) were approximately 3-fold and 13-fold lower, respectively, than those for the highest-dose examination (transjugular intrahepatic portosystemic shunt, TIPS). Median E/DAP conversion factors from 0.12 (abdominal percutaneous transluminal angioplasty) to 0.25 (Nephrostomy) mSvGy{sup -1} cm{sup -2} were obtained and good correlations between E and DAP were found for all procedures, with R{sup 2} coefficients ranging from 0.80 (abdominal angiography) to 0.99 (biliary stent insertion, Nephrostomy and TIPS). The DAP values obtained in this study showed general consistency with the values provided in the literature and median E values ranged from 4.0 mSv (biliary drainage) to 49.6 mSv (TIPS). Conclusions: Values of E/DAP conversion factors were derived for each procedure from a comprehensive analysis of projection and dosimetric data: they could provide a good evaluation for the stochastic effects. These results can be obtained by means of a close cooperation between different interventional professionals involved in patient care and dose optimization.

  11. Factor Analysis via Components Analysis

    ERIC Educational Resources Information Center

    Bentler, Peter M.; de Leeuw, Jan

    2011-01-01

    When the factor analysis model holds, component loadings are linear combinations of factor loadings, and vice versa. This interrelation permits us to define new optimization criteria and estimation methods for exploratory factor analysis. Although this article is primarily conceptual in nature, an illustrative example and a small simulation show…

  12. Ethnomethodology, conversation analysis and education: An overview

    NASA Astrophysics Data System (ADS)

    Watson, D. Rodney

    1992-05-01

    Formal education is saturated with language, but language is usually seen as a separate and often subsidiary topic of research, secondary to social class, ethnicity, etc., which are regarded as independent variables. Ethnomethodology (EM) and Conversation Analysis (CA) are recent approaches devised in North America which propose to make language and the social organization of linguistic interchange a generic topic of investigation. They see mastery of language as central to the ability to make culturally recognizable sense of social interaction. Social class, for example, is thus seen as a worded entity. While EM and CA are sufficiently comprehensive to be applied to any topic, formal education is not stable and constant. It is apprehended differently by the various players of "language games". CA therefore uses "real-world" transcriptions of recordings for analysis of speech exchange. Early CA was concerned with commonsense membership categorizations such as "adult", "child", "adolescent", "mother", "son", "tennis player", which serve as reference points for the imputation of rights and obligations. Stress is now laid on children's techniques of communication, whereas conventional sociology sees the socialization of children as "one-way", from adults to children and frequently ignores children's language. In school tests, for example, it is not certain that children will only use the interpretive resources given them by the teacher, or that they will understand test items in terms of the test design devised by adults. The wider classroom agenda is also set by an adult teacher, who is conventionally the next speaker after each student in formal trum-taking.

  13. Ergosterol-to-Biomass Conversion Factors for Aquatic Hyphomycetes

    PubMed Central

    Gessner, Mark O.; Chauvet, Eric

    1993-01-01

    Fourteen strains of aquatic hyphomycete species that are common on decaying leaves in running waters were grown in liquid culture and analyzed for total ergosterol contents. Media included an aqueous extract from senescent alder leaves, a malt extract broth, and a glucose-mineral salt solution. Concentrations of ergosterol in fungal mycelium ranged from 2.3 to 11.5 mg/g of dry mass. The overall average was 5.5 mg/g. Differences among both species and growth media were highly significant but followed no systematic pattern. Stationary-phase mycelium had ergosterol contents 10 to 12% lower or higher than mycelium harvested during the growth phase, but these differences were only significant for one of four species examined. Availability of plant sterols in the growth medium had no clear effect on ergosterol concentrations in two species tested. To convert ergosterol contents determined in field samples to biomass values of aquatic hyphomycetes, a general multiplicative factor of 182 is proposed. More accurate estimates would be obtained with species-specific factors. Using these in combination with estimates of the proportion of the dominant species in a naturally established community on leaves resulted in biomass estimates that were typically 20% lower than those obtained with the general conversion factor. Improvements of estimates with species-specific factors may be limited, however, by intraspecific variability in fungal ergosterol content. PMID:16348874

  14. Conversion factors: SI metric and U.S. customary units

    USGS Publications Warehouse

    U.S. Geological Survey

    1977-01-01

    The policy of the U.S. Geological Survey is to foster use of the International System of Units (SI) which was defined by the 11th General Conference of Weights and Measures in 1960. This modernized metric system constitutes an international "language" by means of which communications throughout the world's scientific and economic communities may be improved. This publication is designed to familiarize the reader with the SI units of measurement that correspond to the common units frequently used in programs of the Geological Survey. In the near future, SI units will be used exclusively in most publications of the Survey; the conversion factors provided herein will help readers to obtain a "feel" for each unit and to "think metric."

  15. Introduction: Conversation Analysis in Applied Linguistics

    ERIC Educational Resources Information Center

    Sert, Olcay; Seedhouse, Paul

    2011-01-01

    This short, introductory paper presents an up-to-date account of works within the field of Applied Linguistics which have been influenced by a Conversation Analytic paradigm. The article reviews recent studies in classroom interaction, materials development, proficiency assessment and language teacher education. We believe that the publication of…

  16. Impact of HFIR LEU Conversion on Beryllium Reflector Degradation Factors

    SciTech Connect

    Ilas, Dan

    2013-10-01

    An assessment of the impact of low enriched uranium (LEU) conversion on the factors that may cause the degradation of the beryllium reflector is performed for the High Flux Isotope Reactor (HFIR). The computational methods, models, and tools, comparisons with previous work, along with the results obtained are documented and discussed in this report. The report documents the results for the gas and neutronic poison production, and the heating in the beryllium reflector for both the highly enriched uranium (HEU) and LEU HFIR configurations, and discusses the impact that the conversion to LEU may have on these quantities. A time-averaging procedure was developed to calculate the isotopic (gas and poisons) production in reflector. The sensitivity of this approach to different approximations is gauged and documented. The results show that the gas is produced in the beryllium reflector at a total rate of 0.304 g/cycle for the HEU configuration; this rate increases by ~12% for the LEU case. The total tritium production rate in reflector is 0.098 g/cycle for the HEU core and approximately 11% higher for the LEU core. A significant increase (up to ~25%) in the neutronic poisons production in the reflector during the operation cycles is observed for the LEU core, compared to the HEU case, for regions close to the core s horizontal midplane. The poisoning level of the reflector may increase by more than two orders of magnitude during long periods of downtime. The heating rate in the reflector is estimated to be approximately 20% lower for the LEU core than for the HEU core. The decrease is due to a significantly lower contribution of the heating produced by the gamma radiation for the LEU core. Both the isotopic (gas and neutronic poisons) production and the heating rates are spatially non-uniform throughout the beryllium reflector volume. The maximum values typically occur in the removable reflector and close to the midplane.

  17. Vocabulary Explanations in CLIL Classrooms: A Conversation Analysis Perspective

    ERIC Educational Resources Information Center

    Morton, Tom

    2015-01-01

    This article uses a conversation analysis methodology to examine how lexical Focus on Form is interactionally accomplished in teachers' vocabulary explanations in secondary Content and Language Integrated Learning (CLIL) classrooms. Recent conversation-analytic work has focused on the interactional organisation of vocabulary explanations in…

  18. New conversion factors between human and automatic readouts of the CDMAM phantom for CR systems

    NASA Astrophysics Data System (ADS)

    Hummel, Johann; Homolka, Peter; Osanna-Elliot, Angelika; Kaar, Marcus; Semtrus, Friedrich; Figl, Michael

    2016-03-01

    Mammography screenings demand for profound image quality (IQ) assessment to guarantee their screening success. The European protocol for the quality control of the physical and technical aspects of mammography screening (EPQCM) suggests a contrast detail phantom such as the CDMAM phantom to evaluate IQ. For automatic evaluation a software is provided by the EUREF. As human and automatic readouts differ systematically conversion factors were published by the official reference organisation (EUREF). As we experienced a significant difference for these factors for Computed Radiography (CR) systems we developed an objectifying analysis software which presents the cells including the gold disks randomly in thickness and rotation. This allows to overcome the problem of an inevitable learning effect where observers know the position of the disks in advance. Applying this software, 45 computed radiography (CR) systems were evaluated and the conversion factors between human and automatic readout determined. The resulting conversion factors were compared with the ones resulting from the two methods published by EUREF. We found our conversion factors to be substantially lower than those suggested by EUREF, in particular 1.21 compared to 1.42 (EUREF EU method) and 1.62 (EUREF UK method) for 0.1 mm, and 1.40 compared to 1.73 (EUREF EU) and 1.83 (EUREF UK) for 0.25 mm disc diameter, respectively. This can result in a dose increase of up to 90% using either of these factors to adjust patient dose in order to fulfill image quality requirements. This suggests the need of an agreement on their proper application and limits the validity of the assessment methods. Therefore, we want to stress the need for clear criteria for CR systems based on appropriate studies.

  19. Solar UV geometric conversion factors: horizontal plane to cylinder model.

    PubMed

    Pope, Stanley J; Godar, Dianne E

    2010-01-01

    Most solar UV measurements are relative to the horizontal plane. However, problems arise when one uses those UV measurements to perform risk or benefit assessments because they do not yield the actual doses people get while they are outdoors. To better estimate the UV doses people actually get while outdoors, scientists need geometric conversion factors (GCF) that change horizontal plane irradiances to average irradiances on the human body. Here we describe a simple geometric method that changes unweighted, erythemally weighted and previtamin D(3)-weighted UV irradiances on the horizontal plane to full cylinder and semicylinder irradiances. Scientists can use the full cylinder model to represent the complete human body, while they can use the semicylinder model to represent the face, shoulders, tops of hands and feet. We present daily, monthly and seasonally calculated averages of the GCF for these cylinder models every 5 degrees from 20 to 70 degrees N so that scientists can now get realistic UV doses for people who are outdoors doing a variety of different activities. The GCF show that people actually get less than half their annual erythemally weighted, and consequently half their previtamin D(3)-weighted, UV doses relative to the horizontal plane. Thus, scientists can now perform realistic UV risk and benefit assessments. PMID:20059727

  20. Corn stover availability for biomass conversion: situation analysis

    SciTech Connect

    Hess, J. Richard; Kenney, Kevin L.; Wright, Christopher; Perlack, Robert D; Turhollow, Jr., Anthony

    2009-08-01

    As biorefining conversion technologies become commercial, feedstock availability, supply system logistics, and biomass material attributes are emerging as major barriers to the availability of corn stover for biorefining. While systems do exist to supply corn stover as feedstock to biorefining facilities, stover material attributes affecting physical deconstruction, such as densification and post-harvest material stability, challenge the cost-effectiveness of present-day feedstock logistics systems. In addition, the material characteristics of corn stover create barriers with any supply system design in terms of equipment capacity/efficiency, dry matter loss, and capital use efficiency. However, analysis of a conventional large square bale corn stover feedstock supply system concludes that (1) where other agronomic factors are not limiting, corn stover can be accessed and supplied to a biorefinery using existing bale-based technologies, (2) technologies and new supply system designs are necessary to overcome biomass bulk density and moisture material property challenges, and (3) major opportunities to improve conventional bale biomass feedstock supply systems include improvements in equipment efficiency and capacity and reducing biomass losses in harvesting, collection, and storage. Finally, the backbone of an effective stover supply system design is the optimization of intended and minimization of unintended material property changes as the corn stover passes through the individual supply system processes from the field to the biorefinery conversion processes.

  1. Bayesian Exploratory Factor Analysis

    PubMed Central

    Conti, Gabriella; Frühwirth-Schnatter, Sylvia; Heckman, James J.; Piatek, Rémi

    2014-01-01

    This paper develops and applies a Bayesian approach to Exploratory Factor Analysis that improves on ad hoc classical approaches. Our framework relies on dedicated factor models and simultaneously determines the number of factors, the allocation of each measurement to a unique factor, and the corresponding factor loadings. Classical identification criteria are applied and integrated into our Bayesian procedure to generate models that are stable and clearly interpretable. A Monte Carlo study confirms the validity of the approach. The method is used to produce interpretable low dimensional aggregates from a high dimensional set of psychological measurements. PMID:25431517

  2. Modeling and analysis of energy conversion systems

    SciTech Connect

    Den Braven, K.R. . Dept. of Mechanical Engineering); Stanger, S. )

    1990-10-01

    An investigation was conducted to assess the need for and the feasibility of developing a computer code that could model thermodynamic systems and predict the performance of energy conversion systems. To assess the market need for this code, representatives of a few industrial organizations were contacted, including manufacturers, system and component designers, and research personnel. Researchers and small manufacturers, designers, and installers were very interested in the possibility of using the proposed code. However, large companies were satisfied with the existing codes that they have developed for their own use. Also, a survey was conduced of available codes that could be used or possibly modified for the desired purpose. The codes were evaluated with respect to a list of desirable features, which was prepared as a result of the survey. A few publicly available codes were found that might be suitable. The development, verification, and maintenance of such a code would require a substantial, ongoing effort. 21 refs.

  3. Exploratory Bi-Factor Analysis

    ERIC Educational Resources Information Center

    Jennrich, Robert I.; Bentler, Peter M.

    2011-01-01

    Bi-factor analysis is a form of confirmatory factor analysis originally introduced by Holzinger. The bi-factor model has a general factor and a number of group factors. The purpose of this article is to introduce an exploratory form of bi-factor analysis. An advantage of using exploratory bi-factor analysis is that one need not provide a specific…

  4. Factor Analysis and Counseling Research

    ERIC Educational Resources Information Center

    Weiss, David J.

    1970-01-01

    Topics discussed include factor analysis versus cluster analysis, analysis of Q correlation matrices, ipsativity and factor analysis, and tests for the significance of a correlation matrix prior to application of factor analytic techniques. Techniques for factor extraction discussed include principal components, canonical factor analysis, alpha…

  5. Conversion Intentions of Interns: What Are the Motivating Factors?

    ERIC Educational Resources Information Center

    Hurst, Jessica L.; Good, Linda K.; Gardner, Phil

    2012-01-01

    Purpose: The purpose of this study is to investigate interns' supervisory support expectations, psychological contract obligations, job satisfaction, perception of advancement opportunities and affective organisational commitment in an attempt to gain a better understanding of how these variables influence interns' conversion intentions.…

  6. An experiment to develop conversion factors to standardise measurements of airborne asbestos.

    PubMed

    Dodic-Fikfak, Metoda

    2007-06-01

    Various researchers and agencies recommend different conversion factors for different asbestos exposures. The aim of this study was to develop conversion factors from particles per cm3 (p cm(-3)) to fibres per cm3 (f cm(-3)) and from mg m(-3) to f cm(-3). More than 1000 exposure measurements were available in the Slovenian asbestos-cement factory Salonit Anhovo. Three types of measurement of asbestos concentrations in the air were used: a konimeter measuring p cm-3, a gravimetric method measuring mg m-3 and a membrane filter method measuring f cm-3. Operation-specific conversion factors among these methods were developed. One conversion factor was obtained for asbestos-pipe-dry jobs (4.7) and one for asbestos-sheet-dry jobs (1.6). Only one conversion factor (0.8) was used for asbestos-cement-pipe-wet and asbestos-cement-pipe-dry jobs. For asbestos cement sheets, two conversion factors were obtained (0.3 and 1.2). The development of five different conversion factors made it possible to calculate cumulative exposure to asbestos from historical data and to decrease exposure misclassification. PMID:17562601

  7. Recursive Frame Analysis: A Practitioner's Tool for Mapping Therapeutic Conversation

    ERIC Educational Resources Information Center

    Keeney, Hillary; Keeney, Bradford; Chenail, Ronald J.

    2012-01-01

    Recursive frame analysis (RFA), both a practical therapeutic tool and an advanced qualitative research method that maps the structure of therapeutic conversation, is introduced with a clinical case vignette. We present and illustrate a means of mapping metaphorical themes that contextualize the performance taking place in the room, recursively…

  8. 12 CFR 615.5212 - Credit conversion factors-off-balance sheet items.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 12 Banks and Banking 7 2014-01-01 2014-01-01 false Credit conversion factors-off-balance sheet... Credit conversion factors—off-balance sheet items. (a) The face amount of an off-balance sheet item is generally incorporated into risk-weighted assets in two steps. For most off-balance sheet items, the...

  9. 12 CFR 615.5212 - Credit conversion factors-off-balance sheet items.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 12 Banks and Banking 6 2010-01-01 2010-01-01 false Credit conversion factors-off-balance sheet... Credit conversion factors—off-balance sheet items. (a) The face amount of an off-balance sheet item is generally incorporated into risk-weighted assets in two steps. For most off-balance sheet items, the...

  10. 12 CFR 615.5212 - Credit conversion factors-off-balance sheet items.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 12 Banks and Banking 7 2013-01-01 2013-01-01 false Credit conversion factors-off-balance sheet... Credit conversion factors—off-balance sheet items. (a) The face amount of an off-balance sheet item is generally incorporated into risk-weighted assets in two steps. For most off-balance sheet items, the...

  11. 12 CFR 615.5212 - Credit conversion factors-off-balance sheet items.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 12 Banks and Banking 6 2011-01-01 2011-01-01 false Credit conversion factors-off-balance sheet... Credit conversion factors—off-balance sheet items. (a) The face amount of an off-balance sheet item is generally incorporated into risk-weighted assets in two steps. For most off-balance sheet items, the...

  12. 12 CFR 615.5212 - Credit conversion factors-off-balance sheet items.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 12 Banks and Banking 7 2012-01-01 2012-01-01 false Credit conversion factors-off-balance sheet... Credit conversion factors—off-balance sheet items. (a) The face amount of an off-balance sheet item is generally incorporated into risk-weighted assets in two steps. For most off-balance sheet items, the...

  13. Conversion factors for external gamma dose derived from natural radionuclides in soils.

    PubMed

    Quindos, L S; Fernández, P L; Ródenas, C; Gómez-Arozamena, J; Arteche, J

    2004-01-01

    Field in situ gamma radiation exposure rates and laboratory measured radioactivity contents of 1500 Spanish soils were compared. The main objective was to determine if published theoretically derived conversion factors would yield accurate quantitative activity concentration (Bq kg(-1)) for the data carried out in different surveys developed by our laboratory during the last ten years. The in situ external gamma dose rate results were compared to laboratory gamma analysis of soils samples gathered from each site, considering the concentrations of seven radionuclides: 40K, 214Pb, 214Bi, 212Bi, 212Pb, 208Tl and 228Ac. The coefficient of correlation found between these variables indicate a good relationship. A discussion of the factors contributing to the uncertainties as well as measurement procedure are also given in this paper. PMID:14567949

  14. External dose-rate conversion factors for calculation of dose to the public

    SciTech Connect

    Not Available

    1988-07-01

    This report presents a tabulation of dose-rate conversion factors for external exposure to photons and electrons emitted by radionuclides in the environment. This report was prepared in conjunction with criteria for limiting dose equivalents to members of the public from operations of the US Department of Energy (DOE). The dose-rate conversion factors are provided for use by the DOE and its contractors in performing calculations of external dose equivalents to members of the public. The dose-rate conversion factors for external exposure to photons and electrons presented in this report are based on a methodology developed at Oak Ridge National Laboratory. However, some adjustments of the previously documented methodology have been made in obtaining the dose-rate conversion factors in this report. 42 refs., 1 fig., 4 tabs.

  15. Enhanced target factor analysis.

    PubMed

    Rostami, Akram; Abdollahi, Hamid; Maeder, Marcel

    2016-03-10

    Target testing or target factor analysis, TFA, is a well-established soft analysis method. TFA answers the question whether an independent target test vector measured at the same wavelengths as the collection of spectra in a data matrix can be excluded as the spectrum of one of the components in the system under investigation. Essentially, TFA cannot positively prove that a particular test spectrum is the true spectrum of one of the components, it can, only reject a spectrum. However, TFA will not reject, or in other words TFA will accept, many spectra which cannot be component spectra. Enhanced Target Factor Analysis, ETFA addresses the above problem. Compared with traditional TFA, ETFA results in a significantly narrower range of positive results, i.e. the chance of a false positive test result is dramatically reduced. ETFA is based on feasibility testing as described in Refs. [16-19]. The method has been tested and validated with computer generated and real data sets. PMID:26893084

  16. Planning Document for an NBSR Conversion Safety Analysis Report

    SciTech Connect

    Diamond D. J.; Baek J.; Hanson, A.L.; Cheng, L-Y.; Brown, N.; Cuadra, A.

    2013-09-25

    The NIST Center for Neutron Research (NCNR) is a reactor-laboratory complex providing the National Institute of Standards and Technology (NIST) and the nation with a world-class facility for the performance of neutron-based research. The heart of this facility is the National Bureau of Standards Reactor (NBSR). The NBSR is a heavy water moderated and cooled reactor operating at 20 MW. It is fueled with high-enriched uranium (HEU) fuel elements. A Global Threat Reduction Initiative (GTRI) program is underway to convert the reactor to low-enriched uranium (LEU) fuel. This program includes the qualification of the proposed fuel, uranium and molybdenum alloy foil clad in an aluminum alloy, and the development of the fabrication techniques. This report is a planning document for the conversion Safety Analysis Report (SAR) that would be submitted to, and approved by, the Nuclear Regulatory Commission (NRC) before the reactor could be converted.This report follows the recommended format and content from the NRC codified in NUREG-1537, “Guidelines for Preparing and Reviewing Applications for the Licensing of Non-power Reactors,” Chapter 18, “Highly Enriched to Low-Enriched Uranium Conversions.” The emphasis herein is on the SAR chapters that require significant changes as a result of conversion, primarily Chapter 4, Reactor Description, and Chapter 13, Safety Analysis. The document provides information on the proposed design for the LEU fuel elements and identifies what information is still missing. This document is intended to assist ongoing fuel development efforts, and to provide a platform for the development of the final conversion SAR. This report contributes directly to the reactor conversion pillar of the GTRI program, but also acts as a boundary condition for the fuel development and fuel fabrication pillars.

  17. Dark matter conversion as a source of boost factor

    NASA Astrophysics Data System (ADS)

    Liu, Ze-Peng; Wu, Yue-Liang; Zhou, Yu-Feng

    2012-09-01

    In interacting multi-component dark matter (DM) models, the interactions between the DM components can covert relatively heavy DM components into lighter ones at late times after the thermal decoupling. As a consequence, the relic density of the lightest DM component can be greatly enhanced at late times, which can lead to an alternative source of boost factor required to explain the positron and electron excesses reported by the recent DM indirect search experiments.

  18. Monte Carlo calculations of electron beam quality conversion factors for several ion chamber types

    SciTech Connect

    Muir, B. R.; Rogers, D. W. O.

    2014-11-01

    Purpose: To provide a comprehensive investigation of electron beam reference dosimetry using Monte Carlo simulations of the response of 10 plane-parallel and 18 cylindrical ion chamber types. Specific emphasis is placed on the determination of the optimal shift of the chambers’ effective point of measurement (EPOM) and beam quality conversion factors. Methods: The EGSnrc system is used for calculations of the absorbed dose to gas in ion chamber models and the absorbed dose to water as a function of depth in a water phantom on which cobalt-60 and several electron beam source models are incident. The optimal EPOM shifts of the ion chambers are determined by comparing calculations of R{sub 50} converted from I{sub 50} (calculated using ion chamber simulations in phantom) to R{sub 50} calculated using simulations of the absorbed dose to water vs depth in water. Beam quality conversion factors are determined as the calculated ratio of the absorbed dose to water to the absorbed dose to air in the ion chamber at the reference depth in a cobalt-60 beam to that in electron beams. Results: For most plane-parallel chambers, the optimal EPOM shift is inside of the active cavity but different from the shift determined with water-equivalent scaling of the front window of the chamber. These optimal shifts for plane-parallel chambers also reduce the scatter of beam quality conversion factors, k{sub Q}, as a function of R{sub 50}. The optimal shift of cylindrical chambers is found to be less than the 0.5 r{sub cav} recommended by current dosimetry protocols. In most cases, the values of the optimal shift are close to 0.3 r{sub cav}. Values of k{sub ecal} are calculated and compared to those from the TG-51 protocol and differences are explained using accurate individual correction factors for a subset of ion chambers investigated. High-precision fits to beam quality conversion factors normalized to unity in a beam with R{sub 50} = 7.5 cm (k{sub Q}{sup ′}) are provided. These

  19. Chart of conversion factors: From English to metric system and metric to English system

    USGS Publications Warehouse

    U.S. Geological Survey

    1976-01-01

    The conversion factors in the following tables are for conversion of our customary (English) units of measurement to SI*units, and for convenience, reciprocals are shown for converting SI units back to the English system. The first table contains rule-of-thumb figures, useful for "getting the feel" of SI units or mental estimation. The succeeding tables contain factors accurate to 3 or more significant figures. Please refer to known reference volumes for additional accuracy, as well as for factors dealing with other scientific notation involving SI units.

  20. Conversion Preliminary Safety Analysis Report for the NIST Research Reactor

    SciTech Connect

    Diamond, D. J.; Baek, J. S.; Hanson, A. L.; Cheng, L-Y; Brown, N.; Cuadra, A.

    2015-01-30

    The NIST Center for Neutron Research (NCNR) is a reactor-laboratory complex providing the National Institute of Standards and Technology (NIST) and the nation with a world-class facility for the performance of neutron-based research. The heart of this facility is the NIST research reactor (aka NBSR); a heavy water moderated and cooled reactor operating at 20 MW. It is fueled with high-enriched uranium (HEU) fuel elements. A Global Threat Reduction Initiative (GTRI) program is underway to convert the reactor to low-enriched uranium (LEU) fuel. This program includes the qualification of the proposed fuel, uranium and molybdenum alloy foil clad in an aluminum alloy, and the development of the fabrication techniques. This report is a preliminary version of the Safety Analysis Report (SAR) that would be submitted to the U.S. Nuclear Regulatory Commission (NRC) for approval prior to conversion. The report follows the recommended format and content from the NRC codified in NUREG-1537, “Guidelines for Preparing and Reviewing Applications for the Licensing of Non-power Reactors,” Chapter 18, “Highly Enriched to Low-Enriched Uranium Conversions.” The emphasis in any conversion SAR is to explain the differences between the LEU and HEU cores and to show the acceptability of the new design; there is no need to repeat information regarding the current reactor that will not change upon conversion. Hence, as seen in the report, the bulk of the SAR is devoted to Chapter 4, Reactor Description, and Chapter 13, Safety Analysis.

  1. Quantitative analysis of a wind energy conversion model

    NASA Astrophysics Data System (ADS)

    Zucker, Florian; Gräbner, Anna; Strunz, Andreas; Meyn, Jan-Peter

    2015-03-01

    A rotor of 12 cm diameter is attached to a precision electric motor, used as a generator, to make a model wind turbine. Output power of the generator is measured in a wind tunnel with up to 15 m s-1 air velocity. The maximum power is 3.4 W, the power conversion factor from kinetic to electric energy is cp = 0.15. The v3 power law is confirmed. The model illustrates several technically important features of industrial wind turbines quantitatively.

  2. Nitrogen-to-protein conversion factors for some cereal products in Japan.

    PubMed

    Fujihara, S; Sasaki, H; Aoyagi, Y; Sugahara, T

    2008-04-01

    To evaluate a practical method of determining more accurately conversion factors for calculating the protein contents of foods from the total nitrogen content, 19 cereal products found in Japan were analyzed for total nitrogen, amino acid nitrogen, and amide nitrogen, and then the nitrogen-to-protein conversion factors were calculated. The average conversion factors were 5.75 for rice, 5.81 for wheat, and 5.95 for others. These values, corresponding to the proportion of the amino acid residue to amino acid nitrogen recovered from 20 amino acids, were lower than the currently applied factors to these foods, except for wheat flour and amaranth. The use of this factor for estimating the protein content results in a considerable difference from the estimate based on amino acid residue concentrations, due to the wide variations in amino acid composition and to the presence of a significant level of nonprotein nitrogen. The distribution of the protein nitrogen recovered from the amino acids to total nitrogen averaged 93%. Adjusted conversion factors corresponding to the proportion of the amino acid residue to total nitrogen averaged 5.26 for rice, 5.47 for wheat, and 5.54 for other cereal products. Protein contents estimated using these factors are in good agreement with the contents defined as amino acid residues. PMID:18387100

  3. Multiple conversion between the genes encoding bacterial class-I release factors

    PubMed Central

    Ishikawa, Sohta A.; Kamikawa, Ryoma; Inagaki, Yuji

    2015-01-01

    Bacteria require two class-I release factors, RF1 and RF2, that recognize stop codons and promote peptide release from the ribosome. RF1 and RF2 were most likely established through gene duplication followed by altering their stop codon specificities in the common ancestor of extant bacteria. This scenario expects that the two RF gene families have taken independent evolutionary trajectories after the ancestral gene duplication event. However, we here report two independent cases of conversion between RF1 and RF2 genes (RF1-RF2 gene conversion), which were severely examined by procedures incorporating the maximum-likelihood phylogenetic method. In both cases, RF1-RF2 gene conversion was predicted to occur in the region encoding nearly entire domain 3, of which functions are common between RF paralogues. Nevertheless, the ‘direction’ of gene conversion appeared to be opposite from one another—from RF2 gene to RF1 gene in one case, while from RF1 gene to RF2 gene in the other. The two cases of RF1-RF2 gene conversion prompt us to propose two novel aspects in the evolution of bacterial class-I release factors: (i) domain 3 is interchangeable between RF paralogues, and (ii) RF1-RF2 gene conversion have occurred frequently in bacterial genome evolution. PMID:26257102

  4. A new technique for measuring gas conversion factors for hydrocarbon mass flowmeters

    NASA Technical Reports Server (NTRS)

    Singh, J. J.; Sprinkle, D. R.

    1983-01-01

    A technique for measuring calibration conversion factors for hydrocarbon mass flowmeters was developed. It was applied to a widely used type of commercial thermal mass flowmeter for hydrocarbon gases. The values of conversion factors for two common hydrocarbons measured using this technique are in good agreement with the empirical values cited by the manufacturer. Similar agreements can be expected for all other hydrocarbons. The technique is based on Nernst theorem for matching the partial pressure of oxygen in the combustion product gases with that in normal air. It is simple, quick and relatively safe--particularly for toxic/poisonous hydrocarbons.

  5. Network generation and analysis of complex biomass conversion systems

    SciTech Connect

    Rangarajan, S.; Kaminski, T.; Van Wyk, E.; Bhan, A.; Daoutidis, P.

    2011-01-01

    A modular computational tool for automated generation and rule-based post-processing of reaction systems in biomass conversion is presented. Cheminformatics and graph theory algorithms are used to generate chemical transformations pertaining to heterogeneous and homogeneous chemistries in the automated rule-based network generator. A domain-specific language provides a user-friendly English-like chemistry specification interface to the network generator. A rule-based pathway analysis module enables the user to extract and query pathways from the reaction network. A demonstration of the features of this tool is presented using Fructose to 5-Hydroxymethylfurfural as a case study.

  6. Computation of cross sections and dose conversion factors for criticality accident dosimetry.

    PubMed

    Devine, R T

    2004-01-01

    In the application of criticality accident dosemeters the cross sections and fluence-to-dose conversion factors have to be computed. The cross section and fluence-to-dose conversion factor for the thermal and epi-thermal contributions to neutron dose are well documented; for higher energy regions (>100 keV) these depend on the spectrum assumed. Fluence is determined using threshold detectors. The cross sections require the folding of an expected spectrum with the reaction cross sections. The fluence-to-dose conversion factors also require a similar computation. The true and effective thresholds are used to include the information on the expected spectrum. The spectra can either be taken from compendia or measured at the facility at which the exposures are to be expected. The cross sections can be taken from data computations or analytic representations and the fluence-to-dose conversion factors are determined by various standards making bodies. The problem remaining is the method of computation. The purpose of this paper is to compare two methods for computing these factors: analytic and Monte Carlo. PMID:15353697

  7. The CO-H2 Conversion Factor in Star-Forming Galaxies at z<1.5

    NASA Astrophysics Data System (ADS)

    Carleton, Timothy; Cooper, Mike; PHIBSS team

    2016-06-01

    Using data drawn from the Plateau de Bure High-z Blue Sequence Survey (PHIBSS) and the CO Legacy Database for GASS (COLD GASS), we study the correlation between the CO-H2 conversion factor (αco) and integrated galaxy properties, such as gas-phase metallicity and total mass surface density, for a sample of ~200 star-forming galaxies at z < 1.5. Consistent with existing observations, we find a weak anti-correlation between αco and metallicity, such that the most metal-poor galaxies exhibit an αco in excess of that observed in the Milky Way disk. Contrary to theoretical predictions, however, we find no significant correlation between αco and total mass surface density at z ~ 0 or z ~ 1; our results indicate that molecular gas primarily exists in the form of Milky Way-like GMCs in typical star-forming galaxies at z < 1.5, independent of the galaxy's mass surface density. For massive galaxies on the star-forming "main sequence" at z ~ 1, we find a factor of 4 difference in the molecular depletion timescales inferred using the predicted CO-H2 conversion factor versus those inferred using a Milky Way-like αco. This analysis underscores the importance of the CO-H2 conversion factor in interpreting CO observations, both locally and especially at high redshift during the peak of cosmic star formation.

  8. Corn Stover Availability for Biomass Conversion: Situation Analysis

    SciTech Connect

    J. Richard Hess; Kevin L. Kenney; Christopher T. Wright; Robert Perlack; Anthony Turhollow

    2009-08-01

    As biorefining conversion technologies become commercial, feedstock availability, supply system logistics, and biomass material attributes are emerging as major barriers to the availability of corn stover for biorefining. While systems do exist to supply corn stover as feedstock to biorefining facilities, stover material attributes affecting physical deconstruction, such as densification and post-harvest material stability, challenge the cost-effectiveness of present-day feedstock logistics systems. In addition, the material characteristics of corn stover create barriers with any supply system design in terms of equipment capacity/efficiency, dry matter loss, and capital use efficiency. However, this study of a large, square-bale corn stover feedstock supply system concludes that (1) where other agronomic factors are not limiting, corn stover can be accessed and supplied to a biorefinery using existing bale-based technologies, (2) technologies and new supply system designs are necessary to overcome biomass bulk density and moisture material property challenges, and (3) major opportunities to improve conventional-bale biomass feedstock supply systems include improvements in equipment efficiency and capacity and reducing biomass losses in harvesting and collection and storage. Finally, the backbone of an effective stover supply system design is the optimization of intended and minimization of unintended material property changes as the corn stover passes through the individual supply system processes from the field to the biorefinery conversion processes.

  9. A critical review on photochemical conversions in flow analysis.

    PubMed

    Rocha, Diogo L; Kamogawa, Marcos Y; Rocha, Fábio R P

    2015-10-01

    Photochemical conversions are cost-effective and environmental friendly processes that require mild experimental conditions and avoid generation of highly acidic wastes. Treated samples are then compatible with most of the analytical techniques. These characteristics become more relevant when the photoconversions are accomplished to flow analysis, thus allowing exploitation of incomplete reactions, the effective use of the photogenerated unstable radicals and in-line sample treatment. Decreasing of reagent consumption and waste generation, sample processing in a closed environment, and improvement of efficiency of the photochemical processes are other inherent advantages. These aspects are critically reviewed in this article, which emphasizes applications to fractionation and speciation analysis, photo-induced luminescence, miniaturization, and in-line waste treatment. Design of flow-through photochemical cells, use of auxiliary reagents in homogeneous and heterogeneous media, and configurations of flow manifolds are also discussed. PMID:26481985

  10. The CO-H2 conversion factor and the CO excitation ladder

    NASA Astrophysics Data System (ADS)

    Christian, Joel Robert; Narayanan, Desika

    2015-01-01

    Indirect measurements of molecular hydrogen mass are can be made using the CO line intensity. Previous work has shown that the star formation rate surface density can be used to parameterize the conversion factor (XCO). There is further evidence to suggest that the physical conditions which determine the CO spectral line energy distribution (SLED) also determine the conversion factor from CO line intensity to molecular gas mass conversion factor (XCO). Here, we present a series of SPH simulations of idealized galaxies in evolution, focusing on their Giant Molecular Cloud properties. We simulate a range of both disk galaxies and galaxy mergers with a wide range of star formation rates, velocity dispersions, gas metallicities and temperatures. From these varying simulations we perform full radiative transfer calculations with conditions derived from the simulated GMCs. These calculations will determine theoretical values of the conversion factor (XCO) as well as CO SLEDs. We aim to find a relationship between XCO and the CO SLED that will help inform observers in the era of ALMA.

  11. Empirically Based Conversion Factors for Calculating Couple-Years of Protection.

    ERIC Educational Resources Information Center

    Stover, John; Bertrand, Jane T.; Shelton, James D.

    2000-01-01

    Presents conversion factors to be used to translate the quality of the respective contraception methods distributed to a single measure of protection for calculating couple-years of protection in family planning studies. Discusses the implications for the evaluation of family planning programs. (SLD)

  12. Comparison of 50-year and 70-year internal-dose-conversion factors

    SciTech Connect

    Ryan, M.T.; Dunning, D.E. Jr.

    1981-03-01

    The 50-year inhalation and ingestion dose commitments associated with an acute intake (of a radionuclide) of 3.7 x 10/sup 4/ Bq (1 ..mu..Ci) in one day were compared with the corresponding dose commitments calculated for a 70-year integration period resulting from a chronic intake of the same amount at a rate of 101 Bq/d (0.00274 ..mu..Ci/d) for one year. These values, known as dose conversion factors, estimate the dose accumulated during a given period of time following a unit of intake of a radionuclide. It was demonstrated that the acute intake of 3.7 x 10/sup 4/ Bq in one day and the chronic intake of 101 Bq/d for one year (a total intake of 3.7 x 10/sup 4/ Bq) result in essentially the same dose commitment for a relatively long integration period. Therefore, the comparison of 50-year acute dose conversion factors and 70-year chronic dose conversion factors is essentially only a measure of the additional dose accumulated in the 50 to 70 year period. It was found that for radionuclides with atomic mass less than 200 the percent difference in the 70-year and 50-year dose conversion factors was essentially zero in most cases. Differences of approximately 5 to 50% were obtained for dose conversion factors for most alpha emitters with atomic masses of greater than 200. Comparisons were made on the basis of both organ dose equivalent and effective dose equivalent. The implications and significance of these results are discussed.

  13. Q Conversion Factor Models for Estimating Precipitable Water Vapor for Turkey

    NASA Astrophysics Data System (ADS)

    Deniz, Ilke; Mekik, Cetin; Gurbuz, Gokhan

    2015-04-01

    precipitable water vapor is the conversion factor Q which is shown in Emardson and Derks' studies and also Jade and Vijayan's. Developing a regional model using either Tm-Ts equation or the conversion factor Q will provide a basis for GNSS Meteorology in Turkey which depends on the analysis of the radiosonde profile data. For this purpose, the radiosonde profiles from Istanbul, Ankara, Diyarbaki r, Samsun, Erzurum, Izmir, Isparta and Adana stations are analyzed with the radiosonde analysis algorithm in the context of the 'The Estimation of Atmospheric Water Vapour with GPS' Project which is funded by the Scientific and Technological Research Council of Turkey (TUBITAK). The Project is also in the COST Action ES1206: Advanced Global Navigation Satellite Systems tropospheric products for monitoring severe weather events and climate (GNSS4SWEC). In this study, regional models using the conversion factor Q are used for the determination of precipitable water vapor, and applied to the GNSS derived wet tropospheric zenith delays. Henceforth, the estimated precipitable water vapor and the precipitable water vapor obtained from the radiosonde station are compared. The average of the differences between RS and models for Istanbul and Ankara stations are obtained as 2.0±1.6 mm, 1.6±1.6 mm, respectively.

  14. Factor Analysis of Intern Effectiveness

    ERIC Educational Resources Information Center

    Womack, Sid T.; Hannah, Shellie Louise; Bell, Columbus David

    2012-01-01

    Four factors in teaching intern effectiveness, as measured by a Praxis III-similar instrument, were found among observational data of teaching interns during the 2010 spring semester. Those factors were lesson planning, teacher/student reflection, fairness & safe environment, and professionalism/efficacy. This factor analysis was as much of a…

  15. Effects of protocol and obesity on dose conversion factors in adult body CT

    PubMed Central

    Li, Xiang; Samei, Ehsan; Williams, Cameron H.; Segars, W. Paul; Tward, Daniel J.; Miller, Michael I.; Ratnanather, J. Tilak; Paulson, Erik K.; Frush, Donald P.

    2012-01-01

    Purpose: In computed tomography (CT), organ dose, effective dose, and risk index can be estimated from volume-weighted CT dose index (CTDIvol) or dose-length product (DLP) using conversion coefficients. Studies have investigated how these coefficients vary across scanner models, scan parameters, and patient size. However, their variability across CT protocols has not been systematically studied. Furthermore, earlier studies of the effect of patient size have not included obese individuals, which currently represent more than one-third of U.S. adults. The purpose of this study was to assess the effects of protocol and obesity on dose and risk conversion coefficients in adult body CT. Methods: Whole-body computational phantoms were created from clinical CT images of six adult patients (three males, three females), representing normal-weight patients and patients of three obesity classes. Body CT protocols at our institution were selected and categorized into ten examination categories based on anatomical region examined. A validated Monte Carlo program was used to estimate organ dose. Organ dose estimates were normalized by CTDIvol and size-specific dose estimate (SSDE) to obtain organ dose conversion coefficients (denoted as h and hss factors, respectively). Assuming each phantom to be 20, 40, and 60 years old, effective dose and risk index were calculated and normalized by DLP to obtain effective dose and risk index conversion coefficients (denoted as k and q factors, respectively). Coefficient of variation was used to quantify the variability of each conversion coefficient across examination categories. The effect of obesity was assessed by comparing each obese phantom with the normal-weight phantom of the same gender. Results: For a given organ, the variability of h factor across examination categories that encompassed the entire organ volume was generally within 15%. However, k factor varied more across examination categories (15%–27%). For all three ages, the

  16. Conversion factors from counts to chemical ratios for the EURITRACK tagged neutron inspection system

    NASA Astrophysics Data System (ADS)

    El Kanawati, W.; Perot, B.; Carasco, C.; Eleon, C.; Valkovic, V.; Sudac, D.; Obhodas, J.

    2011-10-01

    The EURopean Illicit TRAfficking Countermeasures Kit (EURITRACK) uses 14 MeV neutrons produced by the 3H(d,n) 4H fusion reaction to detect explosives and narcotics in cargo containers. Reactions induced by fast neutrons produce gamma rays, which are detected in coincidence with the associated alpha particle to determine the neutron direction. In addition, the neutron path length is obtained from a time-of-flight measurement, thus allowing the origin of the gamma rays inside the container to be determined. Information concerning the chemical composition of the target material is obtained from the analysis of the energy spectrum. The carbon, oxygen, and nitrogen relative count contributions must be converted to chemical proportions to distinguish illicit and benign organic materials. An extensive set of conversion factors based on Monte Carlo numerical simulations has been calculated, taking into account neutron slowing down and photon attenuation in the cargo materials. An experimental validation of the method is presented by comparing the measured chemical fractions of known materials, in the form of bare samples or hidden in a cargo container, to their real chemical composition. Examples of application to real cargo containers are also reported, as well as simulated data with explosives and illicit drugs.

  17. Discourse Analysis and Cultivation of Conversational Competence in English Class

    ERIC Educational Resources Information Center

    Zhang, Zheng

    2008-01-01

    The essay is to discuss in perspective of teaching how to apply the results of Discourse Analysis study to English class to train students for successful communication through taking turns, controlling turns, teaching exchange, organizing transaction, spreading topic and taking into account contextual factors as well in order to cultivate…

  18. Dose-rate conversion factors for external exposure to photons and electrons

    SciTech Connect

    Kocher, D. C.

    1980-01-01

    This paper describes recent modifications of the computer code DOSFACTER, which was developed for the purpose of estimating dose-rate conversion factors for external exposure to photons and electrons emitted by radionuclides dispersed in the environment. The modifications and additions which have been made to the calculations outlined above include the following: (1) calculation of electron dose-rate factors for radiosensitive portions of the skin; (2) incorporation of improved estimates of organ dose-rate factors for photons; and (3) calculation of dose-rate factors for additional radio nuclides and incorporation of updated radioactive decay data for all radionuclides. The revised dose-rate factors described in this paper are available upon request from the Radiation Shielding Information Center at Oak Ridge National Laboratory.

  19. Ocean Thermal Energy Conversion (OTEC) Programmatic Environmental Analysis--Appendices

    SciTech Connect

    Authors, Various

    1980-01-01

    The programmatic environmental analysis is an initial assessment of Ocean Thermal Energy Conversion (OTEC) technology considering development, demonstration and commercialization. It is concluded that the OTEC development program should continue because the development, demonstration, and commercialization on a single-plant deployment basis should not present significant environmental impacts. However, several areas within the OTEC program require further investigation in order to assess the potential for environmental impacts from OTEC operation, particularly in large-scale deployments and in defining alternatives to closed-cycle biofouling control: (1) Larger-scale deployments of OTEC clusters or parks require further investigations in order to assess optimal platform siting distances necessary to minimize adverse environmental impacts. (2) The deployment and operation of the preoperational platform (OTEC-1) and future demonstration platforms must be carefully monitored to refine environmental assessment predictions, and to provide design modifications which may mitigate or reduce environmental impacts for larger-scale operations. These platforms will provide a valuable opportunity to fully evaluate the intake and discharge configurations, biofouling control methods, and both short-term and long-term environmental effects associated with platform operations. (3) Successful development of OTEC technology to use the maximal resource capabilities and to minimize environmental effects will require a concerted environmental management program, encompassing many different disciplines and environmental specialties. This volume contains these appendices: Appendix A -- Deployment Scenario; Appendix B -- OTEC Regional Characterization; and Appendix C -- Impact and Related Calculations.

  20. Numerical analysis of seismoelectromagnetic field conversion at confined geological units

    NASA Astrophysics Data System (ADS)

    Kroeger, B.; Kemna, A.

    2010-12-01

    It is well known that at material boundaries in fluid-saturated porous media, an incoming seismic wave can give rise to electric and magnetic fields due to electrokinetic coupling effects. Given its sensitivity to rock parameters governing fluid flow, this so-called seismoelectromagnetic (or seismoelectric, if only the electric field is considered) interface response is of strong interest with a view to hydro geophysical and petroleum exploration applications. However, the understanding of the correspondence of the converting interface geometry on the one hand and electric and magnetic field characteristics on the other hand is still poor. By means of two-dimensional finite-element modeling in the time domain, we here investigate the character of the seismoelectromagnetic interface response for the special case of spatially confined geological units, which may be representative for clay lenses embedded in an aquifer or petroleum deposits in a host rock. In the numerical analysis we consider the interface response generated by both compressional and shear wave. The modeling results, which are analyzed in terms of snapshots, time slices, and electro and magneto grams, reveal a significant influence of the confined geological units on the generation and character of the seismoelectro-magnetic interface response. The different conversion patterns can be attributed to the induced streaming currents at the interfaces caused by the oscillation of the seismic body waves. Pattern analysis of the interface responses is done with a view to an improved qualitative understanding of their spatio-temporal occurrence and evolution relative to the geometry of the converting interfaces. Our time-lapse simulations illustrate that the seismoelectromagnetic interface response captures characteristics of the geometry of the converting geological unit, indicating the potential of the seismoelectromagnetic method in particular for exploration of confined targets.

  1. Tracing Developmental Changes through Conversation Analysis: Cross-Sectional and Longitudinal Analysis

    ERIC Educational Resources Information Center

    Lee, Yo-An; Hellermann, John

    2014-01-01

    The descriptive focus of conversation analysis (CA) has not been considered optimal for second language (L2) acquisition research. Recently, however, some CA researchers have addressed the developmental agenda by examining longitudinal data (e.g., Brouwer, C., 2004; Ishida, M., 2009; Markee, N., 2008; Pekarek-Doehler, S., 2010). The present…

  2. Conversation Analysis--A Discourse Approach to Teaching Oral English Skills

    ERIC Educational Resources Information Center

    Wu, Yan

    2013-01-01

    This paper explores a pedagocial approach to teaching oral English---Conversation Analysis. First, features of spoken language is described in comparison to written language. Second, Conversation Analysis theory is elaborated in terms of adjacency pairs, turn-taking, repairs, sequences, openings and closings, and feedback. Third, under the…

  3. Dose-rate conversion factors for external exposure to photons and electrons

    SciTech Connect

    Kocher, D.C.

    1981-08-01

    Dose-rate conversion factors for external exposure to photons and electrons have been calculated for approximately 500 radionuclides of potential importance in environmental radiological assessments. The dose-rate factors were obtained using the DOSFACTER computer code. The results given in this report incorporate calculation of electron dose-rate factors for radiosensitive tissues of the skin, improved estimates of organ dose-rate factors for photons, based on organ doses for monoenergetic sources at the body surface of an exposed individual, and the spectra of scattered photons in air from monoenergetic sources in an infinite, uniformly contaminated atmospheric cloud, calculation of dose-rate factors for other radionuclides in addition to those of interest in the nuclear fuel cycle, and incorporation of updated radioactive decay data for all radionuclides. Dose-rate factors are calculated for three exposure modes - immersion in contaminated air, immersion in contaminated water, and exposure at a height of 1 m above a contaminated ground surface. The report presents the equations used to calculate the external dose-rate factors for photons and electrons, documentation of the revised DOSFACTER computer code, and a complete tabulation of the calculated dose-rate factors. 30 refs., 12 figs.

  4. Direct measurement of electron beam quality conversion factors using water calorimetry

    SciTech Connect

    Renaud, James Seuntjens, Jan; Sarfehnia, Arman; Marchant, Kristin; McEwen, Malcolm; Ross, Carl

    2015-11-15

    Purpose: In this work, the authors describe an electron sealed water calorimeter (ESWcal) designed to directly measure absorbed dose to water in clinical electron beams and its use to derive electron beam quality conversion factors for two ionization chamber types. Methods: A functioning calorimeter prototype was constructed in-house and used to obtain reproducible measurements in clinical accelerator-based 6, 9, 12, 16, and 20 MeV electron beams. Corrections for the radiation field perturbation due to the presence of the glass calorimeter vessel were calculated using Monte Carlo (MC) simulations. The conductive heat transfer due to dose gradients and nonwater materials was also accounted for using a commercial finite element method software package. Results: The relative combined standard uncertainty on the ESWcal dose was estimated to be 0.50% for the 9–20 MeV beams and 1.00% for the 6 MeV beam, demonstrating that the development of a water calorimeter-based standard for electron beams over such a wide range of clinically relevant energies is feasible. The largest contributor to the uncertainty was the positioning (Type A, 0.10%–0.40%) and its influence on the perturbation correction (Type B, 0.10%–0.60%). As a preliminary validation, measurements performed with the ESWcal in a 6 MV photon beam were directly compared to results derived from the National Research Council of Canada (NRC) photon beam standard water calorimeter. These two independent devices were shown to agree well within the 0.43% combined relative uncertainty of the ESWcal for this beam type and quality. Absorbed dose electron beam quality conversion factors were measured using the ESWcal for the Exradin A12 and PTW Roos ionization chambers. The photon-electron conversion factor, k{sub ecal}, for the A12 was also experimentally determined. Nonstatistically significant differences of up to 0.7% were found when compared to the calculation-based factors listed in the AAPM’s TG-51 protocol

  5. Factors for conversion between human and automatic read-outs of CDMAM images

    SciTech Connect

    Figl, Michael; Hoffmann, Rainer; Kaar, Marcus; Semturs, Friedrich; Brasik, Natasa; Birkfellner, Wolfgang; Homolka, Peter; Hummel, Johann

    2011-09-15

    Purpose: According to the European protocol for the quality control of the physical and technical aspects of mammography screening (EPQCM) image quality of digital mammography devices has to be assessed using human evaluation of the CDMAM contrast-detail phantom. This is accomplished by the determination of threshold thicknesses of gold disks with different diameters (0.08-2 mm) and revealed to be very time consuming. Therefore a software solution based on a nonprewhitening matched filter (NPW) model was developed at University of Nijmegen. Factors for the conversion from automatic to human readouts have been determined by Young et al.[Proc. SPIE 614206, 1-13 (2006) and Proc. SPIE 6913, 69131C1 (2008)] using a huge amount of data of both human and automatic readouts. These factors depend on the observer groups and are purely phenomenological. The authors present an alternative approach to determine the factors by using the Rose observer model. Methods: Their method uses the Rose theory which gives a relationship between threshold contrast, diameter of the object and number of incident photons. To estimate the conversion factors for the five diameters from 0.2 to 0.5 mm they exposed with five different current-time products which resulted in 25 equations with five unknowns. Results: The theoretical conversion factors (in dependence of the diameters) amounted to be 1.61 {+-} 0.02 (0.2 mm diameter), 1.67 {+-} 0.02 (0.25 mm), 1.85 {+-} 0.02 (0.31 mm), 2.09 {+-} 0.02 (0.4 mm), and 2.28 {+-} 0.02 (0.5 mm). The corresponding phenomenological factors found in literature are 1.74 (0.2 mm), 1.78 (0.25 mm), 1.83 (0.31 mm), 1.88 (0.4 mm), and 1.93 (0.5 mm). Conclusions: They transferred the problem of determining the factors to a well known observer model which has been examined for many years and is also well established. This method reveals to be reproduceable and produces factors comparable to the phenomenological ones.

  6. Defining the Minimal Factors Required for Erythropoiesis through Direct Lineage Conversion.

    PubMed

    Capellera-Garcia, Sandra; Pulecio, Julian; Dhulipala, Kishori; Siva, Kavitha; Rayon-Estrada, Violeta; Singbrant, Sofie; Sommarin, Mikael N E; Walkley, Carl R; Soneji, Shamit; Karlsson, Göran; Raya, Ángel; Sankaran, Vijay G; Flygare, Johan

    2016-06-14

    Erythroid cell commitment and differentiation proceed through activation of a lineage-restricted transcriptional network orchestrated by a group of well characterized genes. However, the minimal set of factors necessary for instructing red blood cell (RBC) development remains undefined. We employed a screen for transcription factors allowing direct lineage reprograming from fibroblasts to induced erythroid progenitors/precursors (iEPs). We show that Gata1, Tal1, Lmo2, and c-Myc (GTLM) can rapidly convert murine and human fibroblasts directly to iEPs. The transcriptional signature of murine iEPs resembled mainly that of primitive erythroid progenitors in the yolk sac, whereas addition of Klf1 or Myb to the GTLM cocktail resulted in iEPs with a more adult-type globin expression pattern. Our results demonstrate that direct lineage conversion is a suitable platform for defining and studying the core factors inducing the different waves of erythroid development. PMID:27264182

  7. Biomass recalcitrance: a multi-scale, multi-factor, and conversion-specific property.

    PubMed

    McCann, Maureen C; Carpita, Nicholas C

    2015-07-01

    Recalcitrance of plant biomass to enzymatic hydrolysis for biofuel production is thought to be a property conferred by lignin or lignin-carbohydrate complexes. However, chemical catalytic and thermochemical conversion pathways, either alone or in combination with biochemical and fermentative pathways, now provide avenues to utilize lignin and to expand the product range beyond ethanol or butanol. To capture all of the carbon in renewable biomass, both lignin-derived aromatics and polysaccharide-derived sugars need to be transformed by catalysts to liquid hydrocarbons and high-value co-products. We offer a new definition of recalcitrance as those features of biomass which disproportionately increase energy requirements in conversion processes, increase the cost and complexity of operations in the biorefinery, and/or reduce the recovery of biomass carbon into desired products. The application of novel processing technologies applied to biomass reveal new determinants of recalcitrance that comprise a broad range of molecular, nanoscale, and macroscale factors. Sampling natural genetic diversity within a species, transgenic approaches, and synthetic biology approaches are all strategies that can be used to select biomass for reduced recalcitrance in various pretreatments and conversion pathways. PMID:26060266

  8. Glossary of terms and table of conversion factors used in design of chemical propulsion systems

    NASA Technical Reports Server (NTRS)

    Keller, R. B., Jr. (Compiler)

    1979-01-01

    The glossary presented is based entirely on terms used in the monographs on Chemical Propulsion. Significant terms relating to material properties and to material fabrication are presented. The terms are arranged in alphabetical order, with multiple word terms appearing in the normal sequence of usage; for example, ablative cooling appears as such, not as cooling, ablative, and lip seal appears as such, not as seal, lip. Conversion Factors for converting U.S. customary units to the International System of Units are presented in alphabetical order of the physical quantity (e.g., density, heat flux, specific impulse) involved.

  9. CO-to-H2 conversion factor of molecular clouds using X-ray shadows

    NASA Astrophysics Data System (ADS)

    Sofue, Yoshiaki; Kataoka, Jun

    2016-06-01

    A new method to determine the CO-to-H2 conversion factor XCO using absorption of diffuse X-ray emission by local molecular clouds was developed. It was applied to the Ophiuchus (G353+17) and Corona Australis (G359-18) clouds using CO line and soft X-ray archival data. We obtained a value XCO = 1.85 ± 0.45 × 1020 H2 cm-2 (K km s-1)-1 as the average of least-χ2 fitting results for R4 (0.7 keV) and R5 (0.8 keV) bands.

  10. Revision of the APGEMS Dose Conversion Factor File Using Revised Factors from Federal Guidance Report 12 and 13.

    SciTech Connect

    Hay, Tristan R.; Rishel, Jeremy P.

    2013-09-30

    The Air Pollutant Graphical Environmental Monitoring System (APGEMS) is used by the Hanford Emergency Operation Center (EOC) to provide refined plume modeling of releases involving radionuclides. The dose conversion factors (DCFs) used by APGEMS to convert air concentration to dose are stored in a file called HUDUFACT.dat; the DCFs are based primarily on ICRP 30 compiled in the late 1980’s. This report updates the DCFs using more recent values reported in the Environmental Protection Agencies (EPAs) Federal Guidance Report (FGR) 12 and 13. FGR 12 provides external exposure (air submersion) DCFs for radionuclides in air; FGR 13 provides DCFs for radionuclides from inhalation. DCFs were updated for only those radionuclides listed in the original HUDUFACT.dat file. Since FGR 13 provides inhalation dose conversion factors as a function of age, revised DCF files were created for APGEMS for each age group. The “adult” DCF file is the most relevant to compare to the original DCF file being used in APGEMS; these DCF values are compared in this report.

  11. Conversion of the Aerodynamic Preliminary Analysis System (APAS) to an IBM PC Compatible Format

    NASA Technical Reports Server (NTRS)

    Kruep, John M.

    1995-01-01

    The conversion of the Aerodynamic Preliminary Analysis System (APAS) software from a Silicon Graphics UNIX-based platform to a DOS-based IBM PC compatible is discussed. Relevant background information is given, followed by a discussion of the steps taken to accomplish the conversion and a discussion of the type of problems encountered during the conversion. A brief comparison of aerodynamic data obtained using APAS with data from another source is also made.

  12. Transforming Rubrics Using Factor Analysis

    ERIC Educational Resources Information Center

    Baryla, Ed; Shelley, Gary; Trainor, William

    2012-01-01

    Student learning and program effectiveness is often assessed using rubrics. While much time and effort may go into their creation, it is equally important to assess how effective and efficient the rubrics actually are in terms of measuring competencies over a number of criteria. This study demonstrates the use of common factor analysis to identify…

  13. Biosphere Dose Conversion Factors for Reasonably Maximally Exposed Individual and Average Member of Critical Group

    SciTech Connect

    K. Montague

    2000-02-23

    The purpose of this calculation is to develop additional Biosphere Dose Conversion Factors (BDCFs) for a reasonably maximally exposed individual (RMEI) for the periods 10,000 years and 1,000,000 years after the repository closure. In addition, Biosphere Dose Conversion Factors for the average member of a critical group are calculated for those additional radionuclides postulated to reach the environment during the period after 10,000 years and up to 1,000,000 years. After the permanent closure of the repository, the engineered systems within the repository will eventually lose their abilities to contain radionuclide inventory, and the radionuclides will migrate through the geosphere and eventually enter the local water table moving toward inhabited areas. The primary release scenario is a groundwater well used for drinking water supply and irrigation, and this calculation takes these postulated releases and follows them through various pathways until they result in a dose to either a member of critical group or a reasonably maximally exposed individual. The pathways considered in this calculation include inhalation, ingestion, and direct exposure.

  14. Home Equity Conversion for the Elderly: An Analysis for Lenders.

    ERIC Educational Resources Information Center

    Weinrobe, Maurice

    This report was prepared to explain home equity conversion (HEC), a means whereby elderly persons can convert the wealth represented by homeownership into a flow of income. It focuses exclusively on arrangements that convert residential equity into discretionary cash. The introduction reviews the recent history of HEC in the United States. A…

  15. Direct Conversion of Fibroblasts into Functional Astrocytes by Defined Transcription Factors

    PubMed Central

    Caiazzo, Massimiliano; Giannelli, Serena; Valente, Pierluigi; Lignani, Gabriele; Carissimo, Annamaria; Sessa, Alessandro; Colasante, Gaia; Bartolomeo, Rosa; Massimino, Luca; Ferroni, Stefano; Settembre, Carmine; Benfenati, Fabio; Broccoli, Vania

    2014-01-01

    Summary Direct cell reprogramming enables direct conversion of fibroblasts into functional neurons and oligodendrocytes using a minimal set of cell-lineage-specific transcription factors. This approach is rapid and simple, generating the cell types of interest in one step. However, it remains unknown whether this technology can be applied to convert fibroblasts into astrocytes, the third neural lineage. Astrocytes play crucial roles in neuronal homeostasis, and their dysfunctions contribute to the origin and progression of multiple human diseases. Herein, we carried out a screening using several transcription factors involved in defining the astroglial cell fate and identified NFIA, NFIB, and SOX9 to be sufficient to convert with high efficiency embryonic and postnatal mouse fibroblasts into astrocytes (iAstrocytes). We proved both by gene-expression profiling and functional tests that iAstrocytes are comparable to native brain astrocytes. This protocol can be then employed to generate functional iAstrocytes for a wide range of experimental applications. PMID:25556566

  16. A Conversation Analysis-Informed Test of L2 Aural Pragmatic Comprehension

    ERIC Educational Resources Information Center

    Walters, F. Scott

    2009-01-01

    Speech act theory-based, second language pragmatics testing (SLPT) raises test-validation issues owing to a lack of correspondence with empirical conversational data. On the assumption that conversation analysis (CA) provides a more accurate account of language use, it is suggested that CA serve as a more empirically valid basis for SLPT…

  17. Biomass Feedstock and Conversion Supply System Design and Analysis

    SciTech Connect

    Jacob J. Jacobson; Mohammad S. Roni; Patrick Lamers; Kara G. Cafferty

    2014-09-01

    Idaho National Laboratory (INL) supports the U.S. Department of Energy’s bioenergy research program. As part of the research program INL investigates the feedstock logistics economics and sustainability of these fuels. A series of reports were published between 2000 and 2013 to demonstrate the feedstock logistics cost. Those reports were tailored to specific feedstock and conversion process. Although those reports are different in terms of conversion, some of the process in the feedstock logistic are same for each conversion process. As a result, each report has similar information. A single report can be designed that could bring all commonality occurred in the feedstock logistics process while discussing the feedstock logistics cost for different conversion process. Therefore, this report is designed in such a way that it can capture different feedstock logistics cost while eliminating the need of writing a conversion specific design report. Previous work established the current costs based on conventional equipment and processes. The 2012 programmatic target was to demonstrate a delivered biomass logistics cost of $55/dry ton for woody biomass delivered to fast pyrolysis conversion facility. The goal was achieved by applying field and process demonstration unit-scale data from harvest, collection, storage, preprocessing, handling, and transportation operations into INL’s biomass logistics model. The goal of the 2017 Design Case is to enable expansion of biofuels production beyond highly productive resource areas by breaking the reliance of cost-competitive biofuel production on a single, low-cost feedstock. The 2017 programmatic target is to supply feedstock to the conversion facility that meets the in-feed conversion process quality specifications at a total logistics cost of $80/dry T. The $80/dry T. target encompasses total delivered feedstock cost, including both grower payment and logistics costs, while meeting all conversion in-feed quality targets

  18. Forest Conversion, Agricultural Transitions and the Influence of Multi-scale Market Factors in Southwest Cameroon

    NASA Astrophysics Data System (ADS)

    Ordway, E.; Lambin, E.; Asner, G. P.

    2015-12-01

    The changing structure of demand for commodities associated with food security and energy has had a startling impact on land use change in tropical forests in recent decades. Yet, the composition of conversion in the Congo basin remains a major uncertainty, particularly with regards to the scale of drivers of change. Owing to rapid expansion of production globally and longstanding historical production locally in the Congo basin, oil palm offers a lens through which to evaluate local land use decisions across a spectrum of small- to large-scales of production as well as interactions with regional and global supply chains. We examined the effect of global commodity crop expansion on land use change in Southwest Cameroon using a mixed-methods approach to integrate remote sensing, field surveys and socioeconomic data. Southwest Cameroon (2.5 Mha) has a long history of large- and small-scale agriculture, ranging from mixed crop subsistence agriculture to large monocrop plantations of oil palm, cocoa, and rubber. Trends and spatial patterns of forest conversion and agricultural transitions were analyzed from 2000-2015 using satellite imagery. We used economic, demographic and field survey datasets to assess how regional and global market factors and local commodity crop decisions affect land use patterns. Our results show that oil palm is a major commodity crop expanding in this region, and that conversion is occurring primarily through expansion by medium-scale producers and local elites. Results also indicate that global and regional supply chain dynamics influence local land use decision making. This research contributes new information on land use patterns and dynamics in the Congo basin, an understudied region. More specifically, results from this research contribute information on recent trends of oil palm expansion in Cameroon that will be used in national land use planning strategies.

  19. A small-form-factor piezoelectric vibration energy harvester using a resonant frequency-down conversion

    NASA Astrophysics Data System (ADS)

    Sun, Kyung Ho; Kim, Young-Cheol; Kim, Jae Eun

    2014-10-01

    While environmental vibrations are usually in the range of a few hundred Hertz, small-form-factor piezoelectric vibration energy harvesters will have higher resonant frequencies due to the structural size effect. To address this issue, we propose a resonant frequency-down conversion based on the theory of dynamic vibration absorber for the design of a small-form-factor piezoelectric vibration energy harvester. The proposed energy harvester consists of two frequency-tuned elastic components for lowering the first resonant frequency of an integrated system but is so configured that an energy harvesting beam component is inverted with respect to the other supporting beam component for a small form factor. Furthermore, in order to change the unwanted modal characteristic of small separation of resonant frequencies, as is the case with an inverted configuration, a proof mass on the supporting beam component is slightly shifted toward a second proof mass on the tip of the energy harvesting beam component. The proposed small-form-factor design capability was experimentally verified using a fabricated prototype with an occupation volume of 20 × 39 × 6.9 mm3, which was designed for a target frequency of as low as 100 Hz.

  20. A small-form-factor piezoelectric vibration energy harvester using a resonant frequency-down conversion

    SciTech Connect

    Sun, Kyung Ho; Kim, Young-Cheol; Kim, Jae Eun

    2014-10-15

    While environmental vibrations are usually in the range of a few hundred Hertz, small-form-factor piezoelectric vibration energy harvesters will have higher resonant frequencies due to the structural size effect. To address this issue, we propose a resonant frequency-down conversion based on the theory of dynamic vibration absorber for the design of a small-form-factor piezoelectric vibration energy harvester. The proposed energy harvester consists of two frequency-tuned elastic components for lowering the first resonant frequency of an integrated system but is so configured that an energy harvesting beam component is inverted with respect to the other supporting beam component for a small form factor. Furthermore, in order to change the unwanted modal characteristic of small separation of resonant frequencies, as is the case with an inverted configuration, a proof mass on the supporting beam component is slightly shifted toward a second proof mass on the tip of the energy harvesting beam component. The proposed small-form-factor design capability was experimentally verified using a fabricated prototype with an occupation volume of 20 × 39 × 6.9 mm{sup 3}, which was designed for a target frequency of as low as 100 Hz.

  1. Charge/mass dynamic structure factors of water and applications to dielectric friction and electroacoustic conversion.

    PubMed

    Sedlmeier, Felix; Shadkhoo, Shahriar; Bruinsma, Robijn; Netz, Roland R

    2014-02-01

    We determine time correlation functions and dynamic structure factors of the number and charge density of liquid water from molecular dynamics simulations. Using these correlation functions we consider dielectric friction and electro-acoustic coupling effects via linear response theory. From charge-charge correlations, the drag force on a moving point charge is derived and found to be maximal at a velocity of around 300 m/s. Strong deviations in the resulting friction coefficients from approximate theory employing a single Debye relaxation mode are found that are due to non-Debye-like resonances at high frequencies. From charge-mass cross-correlations the ultrasonic vibration potential is derived, which characterizes the conversion of acoustic waves into electric time-varying potentials. Along the dispersion relation for normal sound waves in water, the ultrasonic vibration potential is shown to strongly vary and to increase for larger wavelengths. PMID:24511957

  2. Analysis of dynamic effects in solar thermal energy conversion systems

    NASA Technical Reports Server (NTRS)

    Hamilton, C. L.

    1978-01-01

    The paper examines a study the purpose of which is to assess the performance of solar thermal power systems insofar as it depends on the dynamic character of system components and the solar radiation which drives them. Using a dynamic model, the daily operation of two conceptual solar conversion systems was simulated under varying operating strategies and several different time-dependent radiation intensity functions. These curves ranged from smoothly varying input of several magnitudes to input of constant total energy whose intensity oscillated with periods from 1/4 hour to 6 hours.

  3. X-ray beam filtration, dosimetry phantom size and CT patient dose conversion factors.

    PubMed

    Huda, Walter; Sterzik, Alexander; Tipnis, Sameer

    2010-01-21

    We examine how the choice of CT x-ray beam filtration and phantom size influences patient dose (D) to computed tomography dose index (CTDI) conversion factors (i.e. D/CTDI). The ratio of head to body phantom CTDI(w) for a defined scan technique is alpha, and the ratio of organ dose when the body filter is changed to the head filter is beta. CTDI and organ doses were obtained using the ImPACT CT patient dosimetry calculator, and values of alpha and beta were determined for 39 CT scanners. The average value of alpha for the 39 CT scanners covering a 20 year period was 1.99 +/- 0.23, but 30% of scanners had alpha values that differed by more than 10% from the average. For GE, the value of alpha has been approximately constant at approximately 2.0. Both Philips and Siemens show a definite upward trend from values well below 2.0 in the early 1990s to well over 2.0 for their latest models. The data for Toshiba show no overall trend with time with half the data points below 2.0 and the remainder above this value. The average value of beta was 1.09 +/- 0.25. All vendors showed a downward trend in the beta parameter, and where the most recent scanners from each vendor had a beta value close to unity. Our results show that average D/CTDI conversion factors for a body phantom/filter combination are typically double those appropriate for a head phantom/filter combination. PMID:20023330

  4. Efficient computerized model for dynamic analysis of energy conversion systems

    NASA Technical Reports Server (NTRS)

    Hughes, R. D.; Lansing, F. L.; Khan, I. R.

    1983-01-01

    In searching for the optimum parameters that minimize the total life cycle cost of an energy conversion system, various combinations of components are examined and the resulting system performance and associated economics are studied. The systems performance and economics simulation computer program (SPECS) was developed to fill this need. The program simulates the fluid flow, thermal, and electrical characteristics of a system of components on a quasi-steady state basis for a variety of energy conversion systems. A unique approach is used in which the set of characteristic equations is solved by the Newton-Raphson technique. This approach eliminates the tedious iterative loops which are found in comparable programs such as TRNSYS or SOLTES-1. Several efficient features were also incorporated such as the centralized control and energy management scheme, and analogous treatment of energy flow in electrical and mechanical components, and the modeling of components of similar fundamental characteristics using generic subroutines. Initial tests indicate that this model can be used effectively with a relatively small number of time steps and low computer cost.

  5. Efficient computerized model for dynamic analysis of energy conversion systems

    NASA Astrophysics Data System (ADS)

    Hughes, R. D.; Lansing, F. L.; Khan, I. R.

    1983-02-01

    In searching for the optimum parameters that minimize the total life cycle cost of an energy conversion system, various combinations of components are examined and the resulting system performance and associated economics are studied. The systems performance and economics simulation computer program (SPECS) was developed to fill this need. The program simulates the fluid flow, thermal, and electrical characteristics of a system of components on a quasi-steady state basis for a variety of energy conversion systems. A unique approach is used in which the set of characteristic equations is solved by the Newton-Raphson technique. This approach eliminates the tedious iterative loops which are found in comparable programs such as TRNSYS or SOLTES-1. Several efficient features were also incorporated such as the centralized control and energy management scheme, and analogous treatment of energy flow in electrical and mechanical components, and the modeling of components of similar fundamental characteristics using generic subroutines. Initial tests indicate that this model can be used effectively with a relatively small number of time steps and low computer cost.

  6. Does the CO-to-H2 conversion factor depend on the star formation rate?

    NASA Astrophysics Data System (ADS)

    Clark, Paul C.; Glover, Simon C. O.

    2015-09-01

    We present a series of numerical simulations that explore how the `X-factor', XCO - the conversion factor between the observed integrated CO emission and the column density of molecular hydrogen - varies with the environmental conditions in which a molecular cloud is placed. Our investigation is centred around two environmental conditions in particular: the cosmic ray ionization rate (CRIR) and the strength of the interstellar radiation field (ISRF). Since both these properties of the interstellar medium (ISM) have their origins in massive stars, we make the assumption in this paper that both the strength of the ISRF and the CRIR scale linearly with the local star formation rate (SFR). The cloud modelling in this study first involves running numerical simulations that capture the cloud dynamics, as well as the time-dependent chemistry, and ISM heating and cooling. These simulations are then post-processed with a line radiative transfer code to create synthetic 12CO (1-0) emission maps from which XCO can be calculated. We find that for 104 M⊙ virialized clouds with mean density 100 cm- 3, XCO is only weakly dependent on the local SFR, varying by a factor of a few over 2 orders of magnitude in SFR. In contrast, we find that for similar clouds but with masses of 105 M⊙, the X-factor will vary by an order of magnitude over the same range in SFR, implying that extragalactic star formation laws should be viewed with caution. However, for denser (104 cm- 3), supervirial clouds such as those found at the centre of the Milky Way, the X-factor is once again independent of the local SFR.

  7. A Noun Phrase Analysis Tool for Mining Online Community Conversations

    NASA Astrophysics Data System (ADS)

    Haythornthwaite, Caroline; Gruzd, Anatoliy

    Online communities are creating a growing legacy of texts in online bulletin board postings, chat, blogs, etc. These texts record conversation, knowledge exchange, and variation in focus as groups grow, mature, and decline; they represent a rich history of group interaction and an opportunity to explore the purpose and development of online communities. However, the quantity of data created by these communities is vast, and to address their processes in a timely manner requires automated processes. This raises questions about how to conduct automated analyses, and what can we gain from them: Can we gain an idea of community interests, priorities, and operation from automated examinations of texts of postings and patterns of posting behavior? Can we mine stored texts to discover patterns of language and interaction that characterize a community?

  8. Direct calibration in megavoltage photon beams using Monte Carlo conversion factor: validation and clinical implications

    NASA Astrophysics Data System (ADS)

    Wright, Tracy; Lye, Jessica E.; Ramanathan, Ganesan; Harty, Peter D.; Oliver, Chris; Webb, David V.; Butler, Duncan J.

    2015-01-01

    The Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) has established a method for ionisation chamber calibrations using megavoltage photon reference beams. The new method will reduce the calibration uncertainty compared to a 60Co calibration combined with the TRS-398 energy correction factor. The calibration method employs a graphite calorimeter and a Monte Carlo (MC) conversion factor to convert the absolute dose to graphite to absorbed dose to water. EGSnrc is used to model the linac head and doses in the calorimeter and water phantom. The linac model is validated by comparing measured and modelled PDDs and profiles. The relative standard uncertainties in the calibration factors at the ARPANSA beam qualities were found to be 0.47% at 6 MV, 0.51% at 10 MV and 0.46% for the 18 MV beam. A comparison with the Bureau International des Poids et Mesures (BIPM) as part of the key comparison BIPM.RI(I)-K6 gave results of 0.9965(55), 0.9924(60) and 0.9932(59) for the 6, 10 and 18 MV beams, respectively, with all beams within 1σ of the participant average. The measured kQ values for an NE2571 Farmer chamber were found to be lower than those in TRS-398 but are consistent with published measured and modelled values. Users can expect a shift in the calibration factor at user energies of an NE2571 chamber between 0.4-1.1% across the range of calibration energies compared to the current calibration method.

  9. Direct calibration in megavoltage photon beams using Monte Carlo conversion factor: validation and clinical implications.

    PubMed

    Wright, Tracy; Lye, Jessica E; Ramanathan, Ganesan; Harty, Peter D; Oliver, Chris; Webb, David V; Butler, Duncan J

    2015-01-21

    The Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) has established a method for ionisation chamber calibrations using megavoltage photon reference beams. The new method will reduce the calibration uncertainty compared to a (60)Co calibration combined with the TRS-398 energy correction factor. The calibration method employs a graphite calorimeter and a Monte Carlo (MC) conversion factor to convert the absolute dose to graphite to absorbed dose to water. EGSnrc is used to model the linac head and doses in the calorimeter and water phantom. The linac model is validated by comparing measured and modelled PDDs and profiles. The relative standard uncertainties in the calibration factors at the ARPANSA beam qualities were found to be 0.47% at 6 MV, 0.51% at 10 MV and 0.46% for the 18 MV beam. A comparison with the Bureau International des Poids et Mesures (BIPM) as part of the key comparison BIPM.RI(I)-K6 gave results of 0.9965(55), 0.9924(60) and 0.9932(59) for the 6, 10 and 18 MV beams, respectively, with all beams within 1σ of the participant average. The measured kQ values for an NE2571 Farmer chamber were found to be lower than those in TRS-398 but are consistent with published measured and modelled values. Users can expect a shift in the calibration factor at user energies of an NE2571 chamber between 0.4-1.1% across the range of calibration energies compared to the current calibration method. PMID:25565406

  10. The effects of aquaculture production noise on the growth, condition factor, feed conversion, and survival of rainbow trout, Oncorhynchus mykiss

    USGS Publications Warehouse

    Davidson, J.; Bebak, J.; Mazik, P.

    2009-01-01

    Intensive aquaculture systems, particularly recirculating systems, utilize equipment such as aerators, air and water pumps, blowers, and filtration systems that inadvertently increase noise levels in fish culture tanks. Sound levels and frequencies measured within intensive aquaculture systems are within the range of fish hearing, but species-specific effects of aquaculture production noise are not well defined. Field and laboratory studies have shown that fish behavior and physiology can be negatively impacted by intense sound. Therefore, chronic exposure to aquaculture production noise could cause increased stress, reduced growth rates and feed conversion efficiency, and decreased survival. The objective of this study was to provide an in-depth evaluation of the long term effects of aquaculture production noise on the growth, condition factor, feed conversion efficiency, and survival of cultured rainbow trout, Oncorhynchus mykiss. Rainbow trout were cultured in replicated tanks using two sound treatments: 117??dB re 1????Pa RMS which represented sound levels lower than those recorded in an intensive recycle system and 149??dB re 1????Pa RMS, representing sound levels near the upper limits known to occur in recycle systems. To begin the study mean fish weights in the 117 and 149??dB tanks were 40 and 39??g, respectively. After five months of exposure no significant differences were identified between treatments for mean weight, length, specific growth rates, condition factor, feed conversion, or survival (n = 4). Mean final weights for the 117 and 149??dB treatments were 641 ?? 3 and 631 ?? 10??g, respectively. Overall specific growth rates were equal, i.e. 1.84 ?? 0.00 and 1.84 ?? 0.01%/day. Analysis of growth rates of individually tagged rainbow trout indicated that fish from the 149??dB tanks grew slower during the first month of noise exposure (p < 0.05); however, fish acclimated to the noise thereafter. This study further suggests that rainbow trout growth

  11. Reliability and mass analysis of dynamic power conversion systems with parallel of standby redundancy

    NASA Technical Reports Server (NTRS)

    Juhasz, A. J.; Bloomfield, H. S.

    1985-01-01

    A combinatorial reliability approach is used to identify potential dynamic power conversion systems for space mission applications. A reliability and mass analysis is also performed, specifically for a 100 kWe nuclear Brayton power conversion system with parallel redundancy. Although this study is done for a reactor outlet temperature of 1100K, preliminary system mass estimates are also included for reactor outlet temperatures ranging up to 1500 K.

  12. Reliability and mass analysis of dynamic power conversion systems with parallel or standby redundancy

    NASA Technical Reports Server (NTRS)

    Juhasz, Albert J.; Bloomfield, Harvey S.

    1987-01-01

    A combinatorial reliability approach was used to identify potential dynamic power conversion systems for space mission applications. A reliability and mass analysis was also performed, specifically for a 100-kWe nuclear Brayton power conversion system with parallel redundancy. Although this study was done for a reactor outlet temperature of 1100 K, preliminary system mass estimates are also included for reactor outlet temperatures ranging up to 1500 K.

  13. 32P measurement and dose conversion factor evaluation of activated human hair by criticality accident.

    PubMed

    Yoon, Seokwon; Ha, Wi-Ho; Park, Seyoung; Shin, Seongwook; Yoo, Jaeryong; Park, Sunhoo; Lee, Seung-Sook

    2014-10-01

    In order to conduct dose assessment of victims in criticality accidents, a method of fast neutron capture-activated (32)P measurement of hair in which samples are treated by a chemical and analytical procedure that takes 9 h and measurement is conducted by liquid scintillation counting is presented. To validate this measurement method, hair samples spiked with a (32)P reference source were measured and the results analysed and the optimal sample mass and detection efficiency were determined. To verify the correlation between (32)P-specific activity and absorbed dose for spectra with two neutron mean energies, samples collected from three normal individuals were irradiated at various neutron energies and irradiation times using the MC50 Cyclotron of the Korea Institute of Radiological and Medical Sciences. The (32)P-specific activity trend of the irradiated hair agreed well with the absorbed doses. Based on the results, dose conversion factors, which were 0.67 ± 0.15 and 0.59 ± 0.06 Gy (Bq g(-1))(-1) at neutron mean energies of 2.33 and 5.36 MeV, respectively, were calculated as a guide for medical treatment of criticality accident victims. PMID:24516187

  14. Monte Carlo calculation of dose rate conversion factors for external exposure to photon emitters in soil.

    PubMed

    Clouvas, A; Xanthos, S; Antonopoulos-Domis, M; Silva, J

    2000-03-01

    The dose rate conversion factors D(CF) (absorbed dose rate in air per unit activity per unit of soil mass, nGy h(-1) per Bq kg(-1)) are calculated 1 m above ground for photon emitters of natural radionuclides uniformly distributed in the soil. Three Monte Carlo codes are used: 1) The MCNP code of Los Alamos; 2) The GEANT code of CERN; and 3) a Monte Carlo code developed in the Nuclear Technology Laboratory of the Aristotle University of Thessaloniki. The accuracy of the Monte Carlo results is tested by the comparison of the unscattered flux obtained by the three Monte Carlo codes with an independent straightforward calculation. All codes and particularly the MCNP calculate accurately the absorbed dose rate in air due to the unscattered radiation. For the total radiation (unscattered plus scattered) the D(CF) values calculated from the three codes are in very good agreement between them. The comparison between these results and the results deduced previously by other authors indicates a good agreement (less than 15% of difference) for photon energies above 1,500 keV. Antithetically, the agreement is not as good (difference of 20-30%) for the low energy photons. PMID:10688452

  15. Identifying and Exploring Factors Affecting Embodied Conversational Agent Social Presence for Interpersonal Skills Training

    ERIC Educational Resources Information Center

    Chuah, Joon Hao

    2013-01-01

    Embodied conversational agents (ECAs) have been used as virtual conversational partners in interpersonal skills training applications such as medical interviews, military decision making, and cultural training. Ideally, in interpersonal skills training users will perceive and treat the ECAs the same as they would real people. The perception and…

  16. Monte Carlo calculations of k{sub Q}, the beam quality conversion factor

    SciTech Connect

    Muir, B. R.; Rogers, D. W. O.

    2010-11-15

    Purpose: To use EGSnrc Monte Carlo simulations to directly calculate beam quality conversion factors, k{sub Q}, for 32 cylindrical ionization chambers over a range of beam qualities and to quantify the effect of systematic uncertainties on Monte Carlo calculations of k{sub Q}. These factors are required to use the TG-51 or TRS-398 clinical dosimetry protocols for calibrating external radiotherapy beams. Methods: Ionization chambers are modeled either from blueprints or manufacturers' user's manuals. The dose-to-air in the chamber is calculated using the EGSnrc user-code egs{sub c}hamber using 11 different tabulated clinical photon spectra for the incident beams. The dose to a small volume of water is also calculated in the absence of the chamber at the midpoint of the chamber on its central axis. Using a simple equation, k{sub Q} is calculated from these quantities under the assumption that W/e is constant with energy and compared to TG-51 protocol and measured values. Results: Polynomial fits to the Monte Carlo calculated k{sub Q} factors as a function of beam quality expressed as %dd(10){sub x} and TPR{sub 10}{sup 20} are given for each ionization chamber. Differences are explained between Monte Carlo calculated values and values from the TG-51 protocol or calculated using the computer program used for TG-51 calculations. Systematic uncertainties in calculated k{sub Q} values are analyzed and amount to a maximum of one standard deviation uncertainty of 0.99% if one assumes that photon cross-section uncertainties are uncorrelated and 0.63% if they are assumed correlated. The largest components of the uncertainty are the constancy of W/e and the uncertainty in the cross-section for photons in water. Conclusions: It is now possible to calculate k{sub Q} directly using Monte Carlo simulations. Monte Carlo calculations for most ionization chambers give results which are comparable to TG-51 values. Discrepancies can be explained using individual Monte Carlo

  17. Protocol Analysis as a Method for Analyzing Conversational Data.

    ERIC Educational Resources Information Center

    Aleman, Carlos G.; Vangelisti, Anita L.

    Protocol analysis, a technique that uses people's verbal reports about their cognitions as they engage in an assigned task, has been used in a number of applications to provide insight into how people mentally plan, assess, and carry out those assignments. Using a system of networked computers where actors communicate with each other over…

  18. The CO-to-H{sub 2} conversion factor across the Perseus molecular cloud

    SciTech Connect

    Lee, Min-Young; Stanimirović, Snežana; Wolfire, Mark G.; Shetty, Rahul; Glover, Simon C. O.; Molina, Faviola Z.; Klessen, Ralf S.

    2014-03-20

    We derive the CO-to-H{sub 2} conversion factor, X {sub CO} = N(H{sub 2})/I {sub CO}, across the Perseus molecular cloud on sub-parsec scales by combining the dust-based N(H{sub 2}) data with the I {sub CO} data from the COMPLETE Survey. We estimate an average X {sub CO} ∼ 3 × 10{sup 19} cm{sup –2} K{sup –1} km{sup –1} s and find a factor of ∼3 variations in X {sub CO} between the five sub-regions in Perseus. Within the individual regions, X {sub CO} varies by a factor of ∼100, suggesting that X {sub CO} strongly depends on local conditions in the interstellar medium. We find that X {sub CO} sharply decreases at A{sub V} ≲ 3 mag but gradually increases at A{sub V} ≳ 3 mag, with the transition occurring at A{sub V} where I {sub CO} becomes optically thick. We compare the N(H I), N(H{sub 2}), I {sub CO}, and X {sub CO} distributions with two models of the formation of molecular gas, a one-dimensional photodissociation region (PDR) model and a three-dimensional magnetohydrodynamic (MHD) model, tracking both the dynamical and chemical evolution of gas. The PDR model based on the steady state and equilibrium chemistry reproduces our data very well but requires a diffuse halo to match the observed N(H I) and I {sub CO} distributions. The MHD model matches our data reasonably well, suggesting that time-dependent effects on H{sub 2} and CO formation are insignificant for an evolved molecular cloud like Perseus. However, we find interesting discrepancies, including a broader range of N(H I), likely underestimated I {sub CO}, and a large scatter of I {sub CO} at small A{sub V} . These discrepancies most likely result from strong compressions and rarefactions and density fluctuations in the MHD model.

  19. Analysis of a color space conversion engine implemented using dynamic partial reconfiguration

    NASA Astrophysics Data System (ADS)

    Toukatly, Ryan; Patru, Dorin; Saber, Eli; Peskin, Eric; Roylance, Gene; Larson, Brad

    2013-02-01

    Dynamic Partial Reconfiguration allows parts of a Field Programmable Gate Array to be reconfigured, while the rest of the system continues uninterrupted operation. A Color Space Conversion Engine is a digital image-processing pipeline, which requires frequent reconfiguration of some, but not all of its stages. Therefore, it is a digital signal processing system that presumably can take advantage of dynamic partial reconfiguration. This paper describes the necessary design changes, testing, and performance analysis of a color space conversion engine implemented onto a field programmable gate array using dynamic partial reconfiguration. The analysis provides insight into the operational scenarios in which dynamic partial reconfiguration is advantageous or not.

  20. Systems Analysis of Safeguards Effectiveness in a Uranium Conversion Facility

    SciTech Connect

    Elayat, H A; Lambert, H; O'Connell, W J

    2004-06-16

    The U.S. Department of Energy (DOE) is interested in developing tools and methods for potential U.S. use in designing and evaluating safeguards systems. For this goal several DOE National Laboratories are defining the characteristics of typical facilities of several size scales, and the safeguards measures and instrumentation that could be applied. Lawrence Livermore National Laboratory is providing systems modeling and analysis of facility and safeguards operations, diversion path generation, and safeguards system effectiveness. The constituent elements of diversion scenarios are structured using directed graphs (digraphs) and fault trees. Safeguards indicator probabilities are based on sampling statistics and/or measurement accuracies. Scenarios are ranked based on value and quantity of material removed and the estimated probability of non-detection. Significant scenarios, especially those involving timeliness or randomly varying order of events, are transferred to simulation analysis. Simulations show the range of conditions encountered by the safeguards measurements and inspections, e.g., the quantities of intermediate materials in temporary storage and the time sequencing of material flow. Given a diversion campaign, simulations show how much the range of the same parameters observed by the safeguards system can differ from the base-case range. The combination of digraphs, fault trees, statistics and simulation constitute a method for evaluation of the estimated benefit of alternate or additional safeguards equipment or features. A generic example illustrates the method.

  1. Measurement Bias Detection through Factor Analysis

    ERIC Educational Resources Information Center

    Barendse, M. T.; Oort, F. J.; Werner, C. S.; Ligtvoet, R.; Schermelleh-Engel, K.

    2012-01-01

    Measurement bias is defined as a violation of measurement invariance, which can be investigated through multigroup factor analysis (MGFA), by testing across-group differences in intercepts (uniform bias) and factor loadings (nonuniform bias). Restricted factor analysis (RFA) can also be used to detect measurement bias. To also enable nonuniform…

  2. The Infinitesimal Jackknife with Exploratory Factor Analysis

    ERIC Educational Resources Information Center

    Zhang, Guangjian; Preacher, Kristopher J.; Jennrich, Robert I.

    2012-01-01

    The infinitesimal jackknife, a nonparametric method for estimating standard errors, has been used to obtain standard error estimates in covariance structure analysis. In this article, we adapt it for obtaining standard errors for rotated factor loadings and factor correlations in exploratory factor analysis with sample correlation matrices. Both…

  3. OCEAN THERMAL ENERGY CONVERSION (OTEC) PROGRAMMATIC ENVIRONMENTAL ANALYSIS

    SciTech Connect

    Sands, M. D.

    1980-01-01

    This programmatic environmental analysis is an initial assessment of OTEC technology considering development, demonstration and commercialization; it is concluded that the OTEC development program should continue because the development, demonstration, and commercialization on a single-plant deployment basis should not present significant environmental impacts. However, several areas within the OTEC program require further investigation in order to assess the potential for environmental impacts from OTEC operation, particularly in large-scale deployments and in defining alternatives to closed-cycle biofouling control: (1) Larger-scale deployments of OTEC clusters or parks require further investigations in order to assess optimal platform siting distances necessary to minimize adverse environmental impacts. (2) The deployment and operation of the preoperational platform (OTEC-1) and future demonstration platforms must be carefully monitored to refine environmental assessment predictions, and to provide design modifications which may mitigate or reduce environmental impacts for larger-scale operations. These platforms will provide a valuable opportunity to fully evaluate the intake and discharge configurations, biofouling control methods, and both short-term and long-term environmental effects associated with platform operations. (3) Successful development of OTEC technology to use the maximal resource capabilities and to minimize environmental effects will require a concerted environmental management program, encompassing many different disciplines and environmental specialties.

  4. Factor Analysis of Law School Grades.

    ERIC Educational Resources Information Center

    Boldt, Robert F.

    Grades of 116 law school students were obtained from transcripts, along with LSAT, Writing Ability and Background scores. The grades were factored, and an analysis of the goodness of fit of one- through four-factor systems indicated that the system of grades was essentially one factor in nature. A plot of factor loadings for the various courses…

  5. Facet Theory, Smallest Space Analysis, and Factor Analysis.

    ERIC Educational Resources Information Center

    Guttman, Louis

    1982-01-01

    Mathematical and statistical relationships between factor analysis and smallest space analysis are discussed. As spatial analysis of correlation matrices, factor analysis is a special case of smallest space analysis. The two differ in six ways: Shepard diagram, dimensionality, correction for communality, similarity coefficients, regions versus…

  6. Parent-Child Interaction in Nigerian Families: Conversation Analysis, Context and Culture

    ERIC Educational Resources Information Center

    Burns, Annabel; Radford, Julie

    2008-01-01

    This paper uses a conversation analysis (CA) approach to explore parent-child interaction (PCI) within Nigerian families. We illustrate how speech and language therapists (SLTs), by using CA, can tailor recommendations according to the interactional style of each individual family that are consonant with the family's cultural beliefs. Three…

  7. Retrospective Analysis of Cognitive and Affective Responses in Intercultural and Intracultural Conversations

    ERIC Educational Resources Information Center

    Nguyen, Duyen T.; Fussell, Susan R.

    2015-01-01

    We report a study that uses retrospective analysis to understand the relationships between American and Chinese participants' utterances during a conversation and the moment-by-moment feelings and reactions they subsequently described. Intercultural and intracultural pairs of Chinese and American participants talked about a fictional crime story…

  8. Traitement discursif et conversationnel des representations sociales (Discourse and Conversational Analysis of Social Representations).

    ERIC Educational Resources Information Center

    Serra, Cecilia

    2000-01-01

    This article examines the interpretive process of social representations of bilingualism by means of discourse and conversational analysis. Representations are to be understood as an interpretive set of assumptions conveyed by discourse, creating recurrent and habitual systems of dispositions and expectations. The article shows how discourse is…

  9. An Analysis of Adult-Child Conversation Patterns in Diverse African American Families.

    ERIC Educational Resources Information Center

    Tolson, Timothy F. J.; And Others

    1995-01-01

    Examines familial conversation patterns of African American families during evening meals, using a social interaction analysis. Found that family size had a pervasive impact on familial interaction, and that although mothers were the clear focus of mealtime interactions, the increased number of children necessitated that fathers take a more direct…

  10. Echo, Not Quotation: What Conversation Analysis Reveals about Classroom Responses to Heard Poetry

    ERIC Educational Resources Information Center

    Gordon, John

    2012-01-01

    This article applies conversation analysis to classroom talk-in-interaction where pupils respond to poetry they have heard. The phenomenon of repeating in discussion details from the poem, including patterns of delivery, is considered and named echo to distinguish it from quotation in writing. The phenomenon is significant to the pedagogy of…

  11. Inflexibility as an Interactional Phenomenon: Using Conversation Analysis to Re-Examine a Symptom of Autism

    ERIC Educational Resources Information Center

    Muskett, Tom; Perkins, Mick; Clegg, Judy; Body, Richard

    2010-01-01

    Many accounts of autism spectrum disorder (ASD) imply that the condition's behavioural "symptoms" are direct reflexes of underlying deficits. In doing so, however, they invariably overlook the social contexts in which symptomatic behaviours occur and are identified as pathological. This study addresses this issue, using conversation analysis (CA)…

  12. Teacher Guidance of Algebraic Formula Building: Functional Grammatical Analysis of a Whole-Class Conversation

    ERIC Educational Resources Information Center

    Zolkower, Betina; Shreyar, Sam; Pérez, Silvia

    2015-01-01

    How does teacher-guided whole-class interaction contribute to expanding students' potential for making and exchanging mathematical meanings? We address this question through an interpretative analysis of a whole-group conversation in a sixth grade class taught by an experienced teacher in a school in Southern Argentina. The extended interaction…

  13. Conversion factor and uncertainty estimation for quantification of towed gamma-ray detector measurements in Tohoku coastal waters

    NASA Astrophysics Data System (ADS)

    Ohnishi, S.; Thornton, B.; Kamada, S.; Hirao, Y.; Ura, T.; Odano, N.

    2016-05-01

    Factors to convert the count rate of a NaI(Tl) scintillation detector to the concentration of radioactive cesium in marine sediments are estimated for a towed gamma-ray detector system. The response of the detector against a unit concentration of radioactive cesium is calculated by Monte Carlo radiation transport simulation considering the vertical profile of radioactive material measured in core samples. The conversion factors are acquired by integrating the contribution of each layer and are normalized by the concentration in the surface sediment layer. At the same time, the uncertainty of the conversion factors are formulated and estimated. The combined standard uncertainty of the radioactive cesium concentration by the towed gamma-ray detector is around 25 percent. The values of uncertainty, often referred to as relative root mean squat errors in other works, between sediment core sampling measurements and towed detector measurements were 16 percent in the investigation made near the Abukuma River mouth and 5.2 percent in Sendai Bay, respectively. Most of the uncertainty is due to interpolation of the conversion factors between core samples and uncertainty of the detector's burial depth. The results of the towed measurements agree well with laboratory analysed sediment samples. Also, the concentrations of radioactive cesium at the intersection of each survey line are consistent. The consistency with sampling results and between different lines' transects demonstrate the availability and reproducibility of towed gamma-ray detector system.

  14. Comparison of Risk Factors for Unplanned Conversion from Laparoscopic and Robotic to Open Colorectal Surgery Using the Michigan Surgical Quality Collaborative (MSQC) Database.

    PubMed

    Bhama, Anuradha R; Wafa, Abdullah M; Ferraro, Jane; Collins, Stacey D; Mullard, Andrew J; Vandewarker, James F; Krapohl, Greta; Byrn, John C; Cleary, Robert K

    2016-06-01

    Robotic colorectal surgery has been shown to have lower rates of unplanned conversion to open surgery when compared to laparoscopic surgery. Risk factors associated with conversion from robotic to open colectomy and comparisons of the risk factors between robotic and laparoscopic approaches have not been previously reported. Patients who underwent elective laparoscopic and robotic colorectal surgeries between July 1, 2012 and April 28, 2015, were identified in the Michigan Surgical Quality Collaborative registry. Candidate covariates were identified, and hierarchical logistic regression models were used to identify risk factors for conversion. There were 4796 cases that met study inclusion criteria. Conversion was required in 18.2 % of laparoscopic and 7.7 % of robotic cases (p < 0.0001). Risk factors for conversion in the laparoscopic group included the following: moderate/severe adhesions, obesity, colorectal cancer, hypertension, rectal operations, urgent priority, and tobacco use. Risk factors for conversion in the robotic group included the following: severe adhesions, bleeding disorder, presence of cancer, cirrhosis, and use of statins. Higher surgeon volume was protective in both groups. Conversion rates are lower for robotic than for laparoscopic colorectal surgery with fewer predictors of conversion. Recognition of factors predicting conversion may allow surgeons to choose an operative approach that optimizes the benefits of the available technologies. PMID:26847352

  15. 5 CFR Appendix A to Subpart C of... - Present Value Conversion Factors for Earlier Commencing Date of Annuities of Current and Former...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 5 Administrative Personnel 2 2014-01-01 2014-01-01 false Present Value Conversion Factors for...) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES RETIREMENT SYSTEM-DEATH BENEFITS AND EMPLOYEE...—Present Value Conversion Factors for Earlier Commencing Date of Annuities of Current and Former Spouses...

  16. 5 CFR Appendix A to Subpart C of... - Present Value Conversion Factors for Earlier Commencing Date of Annuities of Current and Former...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 5 Administrative Personnel 2 2012-01-01 2012-01-01 false Present Value Conversion Factors for...) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES RETIREMENT SYSTEM-DEATH BENEFITS AND EMPLOYEE...—Present Value Conversion Factors for Earlier Commencing Date of Annuities of Current and Former Spouses...

  17. 5 CFR Appendix A to Subpart C of... - Present Value Conversion Factors for Earlier Commencing Date of Annuities of Current and Former...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 5 Administrative Personnel 2 2011-01-01 2011-01-01 false Present Value Conversion Factors for...) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES RETIREMENT SYSTEM-DEATH BENEFITS AND EMPLOYEE...—Present Value Conversion Factors for Earlier Commencing Date of Annuities of Current and Former Spouses...

  18. 5 CFR Appendix A to Subpart C of... - Present Value Conversion Factors for Earlier Commencing Date of Annuities of Current and Former...

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Present Value Conversion Factors for...) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES RETIREMENT SYSTEM-DEATH BENEFITS AND EMPLOYEE...—Present Value Conversion Factors for Earlier Commencing Date of Annuities of Current and Former Spouses...

  19. 5 CFR Appendix A to Subpart C of... - Present Value Conversion Factors for Earlier Commencing Date of Annuities of Current and Former...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 5 Administrative Personnel 2 2013-01-01 2013-01-01 false Present Value Conversion Factors for...) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES RETIREMENT SYSTEM-DEATH BENEFITS AND EMPLOYEE...—Present Value Conversion Factors for Earlier Commencing Date of Annuities of Current and Former Spouses...

  20. Structuring Health in Colorectal Cancer Screening Conversations: An Analysis of Intersecting Activity Systems

    PubMed Central

    Canary, Heather; Bullis, Connie; Cummings, Jennifer; Kinney, Anita Y.

    2016-01-01

    This study used structurating activity theory to analyze 21 conversations between genetic counselors and individuals at increased risk for familial colorectal cancer (CRC). The qualitative analysis revealed ways elements of family, primary healthcare, cancer prevention and treatment, and other systems emerged in intervention conversations as shaping CRC screening attitudes and behaviors. Results indicate that family stories, norms, and roles are resources for enacting health practices in families and that the authority of healthcare providers is a resource for making screening decisions. Conclusions include practical implications for using findings in clinical applications as well as future research directions to build on this exploratory study. PMID:27182185

  1. ERBS human factors analysis: A case study

    NASA Technical Reports Server (NTRS)

    Moe, K. L.; Weger, C.

    1983-01-01

    The incorporation of human factors into the system development process and the benefits derived are discussed. The human factors analysis task for the Earth radiation budget satellite (ERBS) payload operations control center (POCC) is a pathfinder in the new applications approach to this discipline within the mission and data operations directorate. The topics covered include: discussions of the motivation for human factors analysis; the involvement of the human factors research group (HFRG) with project and system developers, and some examples of human factors issues addressed in the ERBS analysis task.

  2. Conversion and correction factors for historical measurements of Iodine-131 in Hanford-area vegetation, 1945--1947: Draft

    SciTech Connect

    Mart, E.I.; Denham, D.H.; Thiede, M.E.

    1993-05-01

    This report is a result of the Hanford Environmental Dose Reconstruction (HEDR) Project whose goal is to estimate the radiation dose that individuals could have received from emissions since 1944 at the US Department of Energy's (DOE) Hanford Site near Richland, Washington. The report describes in detail the reconstructed conversion and correction factors for historical measurements of iodine-131 in Hanford-area vegetation which was collected from the beginning of October 1945 through the end of December 1947.

  3. Modeling the conversion of hydroacoustic to seismic energy at island and continental margins: preliminary analysis of Ascension Island data

    SciTech Connect

    Harben, P.; Rodgers, A.

    1999-07-26

    Seismic stations at islands and continental margins will be an essential component of the International Monitoring System (IMS) for event location and identification in support of Comprehensive Nuclear-Test-Ban Treaty (CTBT) monitoring. Particularly important will be the detection and analysis of hydroacoustic-to-seismic converted waves (T-phases) at island or continental margins. Acoustic waves generated by sources in or near the ocean propagate for long distances very efficiently due to the ocean sound speed channel (SOFAR) and low attenuation. When ocean propagating acoustic waves strike an island or continental margin they are converted to seismic (elastic) waves. We are using a finite difference code to model the conversion of hydroacoustic T-waves at an island or continental margin. Although ray-based methods are far more efficient for modeling long-range (> 1000 km) high-frequency hydroacoustic propagation, the finite difference method has the advantage of being able to model both acoustic and elastic wave propagation for a broad range of frequencies. The method allows us to perform simulations of T-phases to relatively high frequencies ({>=}10 Hz). Of particular interest is to identify factors that affect the efficiency of T-phase conversion, such as the topographic slope and roughness at the conversion point and elastic velocity structure within the island or continent. Previous studies have shown that efficient T-phase conversion occurs when the topographic slope at the conversion point is steep (Cansi and Bethoux, 1985; Talandier and Okal, 1998). Another factor impacting T-phase conversion may be the near-shore structure of the sound channel. It is well known that the depth to the sound channel axis decreases in shallow waters. This can weaken the channeled hydroacoustic wave. Elastic velocity structure within the island or continent will impact how the converted seismic wave is refracted to recording stations at the surface and thus impact the T

  4. Industrial Power Factor Analysis Guidebook.

    SciTech Connect

    Electrotek Concepts.

    1995-03-01

    Power factor is a way of measuring the percentage of reactive power in an electrical system. Reactive power represents wasted energy--electricity that does no useful work because the electrical current is out of phase with the voltage. Reactive power is used by inductive loads (such as, motors, transformers, fluorescent lights, arc welders and induction furnaces) to sustain their magnetic fields. Electric systems with many motors exhibit low power factors, increased conductor and transformer losses, and lower voltages. Utilities must supply both active and reactive power and compensate for these losses. Power factor can be improved by the addition of shunt capacitors. Capacitors act in opposition to inductive loads, thereby minimizing the reactive power required to serve them. In raising the power factor, shunt capacitors release energy to the system, reduce system losses, and ultimately decrease power costs. Improving system power factor can reduce reactive and active power losses for both industry and utilities through the addition of shunt capacitors. This Guide Book gives electric utility technical staff, industrial end-users, consultants and BPA employees a step-by-step method for evaluating the cost effectiveness of installing power factor correction capacitors in an industrial plant.

  5. Skin dose rate conversion factors after contamination with radiopharmaceuticals: influence of contamination area, epidermal thickness and percutaneous absorption.

    PubMed

    Covens, P; Berus, D; Caveliers, V; Struelens, L; Vanhavere, F; Verellen, D

    2013-06-01

    Skin contamination with radiopharmaceuticals can occur during biomedical research and daily nuclear medicine practice as a result of accidental spills, after contact with bodily fluids of patients or by inattentively touching contaminated materials. Skin dose assessment should be carried out by repeated quantification to map the course of the contamination together with the use of appropriate skin dose rate conversion factors. Contamination is generally characterised by local spots on the palmar surface of the hand and complete decontamination is difficult as a result of percutaneous absorption. This specific issue requires special consideration as to the skin dose rate conversion factors as a measure for the absorbed dose rate to the basal layer of the epidermis. In this work we used Monte Carlo simulations to study the influence of the contamination area, the epidermal thickness and the percutaneous absorption on the absorbed skin dose rate conversion factors for a set of 39 medical radionuclides. The results show that the absorbed dose to the basal layer of the epidermis can differ by up to two orders of magnitude from the operational quantity Hp(0.07) when using an appropriate epidermal thickness in combination with the effect of percutaneous absorption. PMID:23519114

  6. Conversion of Human Fibroblasts to Stably Self-Renewing Neural Stem Cells with a Single Zinc-Finger Transcription Factor.

    PubMed

    Shahbazi, Ebrahim; Moradi, Sharif; Nemati, Shiva; Satarian, Leila; Basiri, Mohsen; Gourabi, Hamid; Zare Mehrjardi, Narges; Günther, Patrick; Lampert, Angelika; Händler, Kristian; Hatay, Firuze Fulya; Schmidt, Diana; Molcanyi, Marek; Hescheler, Jürgen; Schultze, Joachim L; Saric, Tomo; Baharvand, Hossein

    2016-04-12

    Direct conversion of somatic cells into neural stem cells (NSCs) by defined factors holds great promise for mechanistic studies, drug screening, and potential cell therapies for different neurodegenerative diseases. Here, we report that a single zinc-finger transcription factor, Zfp521, is sufficient for direct conversion of human fibroblasts into long-term self-renewable and multipotent NSCs. In vitro, Zfp521-induced NSCs maintained their characteristics in the absence of exogenous factor expression and exhibited morphological, molecular, developmental, and functional properties that were similar to control NSCs. In addition, the single-seeded induced NSCs were able to form NSC colonies with efficiency comparable with control NSCs and expressed NSC markers. The converted cells were capable of surviving, migrating, and attaining neural phenotypes after transplantation into neonatal mouse and adult rat brains, without forming tumors. Moreover, the Zfp521-induced NSCs predominantly expressed rostral genes. Our results suggest a facilitated approach for establishing human NSCs through Zfp521-driven conversion of fibroblasts. PMID:27052315

  7. Conversion of Human Fibroblasts to Stably Self-Renewing Neural Stem Cells with a Single Zinc-Finger Transcription Factor

    PubMed Central

    Shahbazi, Ebrahim; Moradi, Sharif; Nemati, Shiva; Satarian, Leila; Basiri, Mohsen; Gourabi, Hamid; Zare Mehrjardi, Narges; Günther, Patrick; Lampert, Angelika; Händler, Kristian; Hatay, Firuze Fulya; Schmidt, Diana; Molcanyi, Marek; Hescheler, Jürgen; Schultze, Joachim L.; Saric, Tomo; Baharvand, Hossein

    2016-01-01

    Summary Direct conversion of somatic cells into neural stem cells (NSCs) by defined factors holds great promise for mechanistic studies, drug screening, and potential cell therapies for different neurodegenerative diseases. Here, we report that a single zinc-finger transcription factor, Zfp521, is sufficient for direct conversion of human fibroblasts into long-term self-renewable and multipotent NSCs. In vitro, Zfp521-induced NSCs maintained their characteristics in the absence of exogenous factor expression and exhibited morphological, molecular, developmental, and functional properties that were similar to control NSCs. In addition, the single-seeded induced NSCs were able to form NSC colonies with efficiency comparable with control NSCs and expressed NSC markers. The converted cells were capable of surviving, migrating, and attaining neural phenotypes after transplantation into neonatal mouse and adult rat brains, without forming tumors. Moreover, the Zfp521-induced NSCs predominantly expressed rostral genes. Our results suggest a facilitated approach for establishing human NSCs through Zfp521-driven conversion of fibroblasts. PMID:27052315

  8. Management factors affecting mortality, feed intake and feed conversion ratio of grow-finishing pigs.

    PubMed

    Agostini, P S; Fahey, A G; Manzanilla, E G; O'Doherty, J V; de Blas, C; Gasa, J

    2014-08-01

    The aim of this study was to determine the effect of animal management and farm facilities on total feed intake (TFI), feed conversion ratio (FCR) and mortality rate (MORT) of grower-finishing pigs. In total, 310 batches from 244 grower-finishing farms, consisting of 454 855 Pietrain sired pigs in six Spanish pig companies were used. Data collection consisted of a survey on management practices (season of placement, split-sex by pens, number of pig origins, water source in the farm, initial or final BW) and facilities (floor, feeder, ventilation or number of animals placed) during 2008 and 2009. Results indicated that batches of pigs placed between January and March had higher TFI (P=0.006), FCR (P=0.005) and MORT (P=0.03) than those placed between July and September. Moreover, batches of pigs placed between April and June had lower MORT (P=0.003) than those placed between January and March. Batches which had split-sex pens had lower TFI (P=0.001) and better FCR (P<0.001) than those with mixed-sex in pens; pigs fed with a single-space feeder with incorporated drinker also had the lowest TFI (P<0.001) and best FCR (P<0.001) in comparison to single and multi-space feeders without a drinker. Pigs placed in pens with <50% slatted floors presented an improvement in FCR (P<0.05) than pens with 50% or more slatted floors. Batches filled with pigs from multiple origins had higher MORT (P<0.001) than those from a single origin. Pigs housed in barns that performed manual ventilation control presented higher MORT (P<0.001) in comparison to automatic ventilation. The regression analysis also indicated that pigs which entered to grower-finisher facilities with higher initial BW had lower MORT (P<0.05) and finally pigs which were sent to slaughterhouse with a higher final BW presented higher TFI (P<0.001). The variables selected for each dependent variable explained 61.9%, 24.8% and 20.4% of the total variability for TFI, FCR and MORT, respectively. This study indicates that

  9. Conversion Analysis for Mutation Detection in MLH1 and MSH2 in Patients With Colorectal Cancer

    PubMed Central

    Casey, Graham; Lindor, Noralane M.; Papadopoulos, Nickolas; Thibodeau, Stephen N.; Moskow, John; Steelman, Scott; Buzin, Carolyn H.; Sommer, Steve S.; Collins, Christine E.; Butz, Malinda; Aronson, Melyssa; Gallinger, Steven; Barker, Melissa A.; Young, Joanne P.; Jass, Jeremy R.; Hopper, John L.; Diep, Anh; Bapat, Bharati; Salem, Michael; Seminara, Daniela; Haile, Robert

    2010-01-01

    Context The accurate identification and interpretation of germline mutations in mismatch repair genes in colorectal cancer cases is critical for clinical management. Current data suggest that mismatch repair mutations are highly heterogeneous and that many mutations are not detected when conventional DNA sequencing alone is used. Objective To evaluate the potential of conversion analysis compared with DNA sequencing alone to detect heterogeneous germline mutations in MLH1, MSH2, and MSH6 in colorectal cancer patients. Design, Setting, and Participants Multicenter study with patients who participate in the Colon Cancer Family Registry. Mutation analyses were performed in participant samples determined to have a high probability of carrying mismatch repair germline mutations. Samples from a total of 64 hereditary nonpolyposis colorectal cancer cases, 8 hereditary nonpolyposis colorectal cancer–like cases, and 17 cases diagnosed prior to age 50 years were analyzed from June 2002 to June 2003. Main Outcome Measures Classification of family members as carriers or noncarriers of germline mutations in MLH1, MSH2, or MSH6; mutation data from conversion analysis compared with genomic DNA sequencing. Results Genomic DNA sequencing identified 28 likely deleterious exon mutations, 4 in-frame deletion mutations, 16 missense changes, and 22 putative splice site mutations. Conversion analysis identified all mutations detected by genomic DNA sequencing—plus an additional exon mutation, 12 large genomic deletions, and 1 exon duplication mutation—yielding an increase of 33% (14/42) in diagnostic yield of deleterious mutations. Conversion analysis also showed that 4 of 16 missense changes resulted in exon skipping in transcripts and that 17 of 22 putative splice site mutations affected splicing or mRNA transcript stability. Conversion analysis provided an increase of 56% (35/63) in the diagnostic yield of genetic testing compared with genomic DNA sequencing alone. Conclusions

  10. A Primer on Confirmatory Factor Analysis.

    ERIC Educational Resources Information Center

    Gillaspy, James Arthur, Jr.

    This introduction to confirmatory factor analysis presents an overview of its basic concepts and processes. Conventional factor analysis can be described as set of analytic techniques designed to examine the covariance structure of a set of variables and to provide an explanation of the relationships among those variables in terms of a smaller…

  11. Factor Analysis of the Image Correlation Matrix.

    ERIC Educational Resources Information Center

    Kaiser, Henry F.; Cerny, Barbara A.

    1979-01-01

    Whether to factor the image correlation matrix or to use a new model with an alpha factor analysis of it is mentioned, with particular reference to the determinacy problem. It is pointed out that the distribution of the images is sensibly multivariate normal, making for "better" factor analyses. (Author/CTM)

  12. [Impacts of cultivated land conversion on cultivated land productivity in China: prediction and analysis].

    PubMed

    Jiang, Qun-ou; Deng, Xiang-zheng; Lin, Ying-zhi; Cui, Yong-wei

    2010-12-01

    This paper simulated the spatial patterns of cultivated land in China under the future scenario by using the Dynamics of Land System (DLS) model, and then estimated the cultivated land productivity at the grid pixel dimensions based on the Estimation System of Land Production (ESLP). In addition, the spatial patterns of cultivated land productivity in each of China agro-ecological zones were analyzed. On this basis, this paper predicted the impacts of cultivated land conversion on the cultivated land production in China in 2000-2020, and identified the major affecting factors on the cultivated land production. The research results indicated that the impact of improving the cultivated land productivity on the cultivated land production would be wunch more remarkable than that from the magnitude of cultivated land conversion in regions where there were high potential to imrprove the cultivated land productivity. However, in the regions with nearly no room to improve the productivity, cultivated land conversion would produce more apparent impacts on the total cultivated land production. In this sense, it was of significance for the national food security in China to adjust the cultivated land conversion to ensure the 0.12 billion hm2 of cultivated land, and to increase investment and improve management level to increase per unit grain yield. PMID:21442997

  13. Assessment of risk-based capacity benefit factors associated with wind energy conversion systems

    SciTech Connect

    Billinton, R.; Chen, H.

    1998-08-01

    A Wind Energy Conversion System (WECS) has a different impact on the load carry capability of a generating system than does a conventional energy conversion system. This is mainly due to the variation in wind velocity. Two risk-based capacity indices designated as Load Carrying Capacity Benefit Ratio (LCCBR) and Equivalent Capacity Rate (ECR) are introduced in this paper. These two indices can be used to indicate capacity benefit and credit of a WECS, and thus provide valuable information for energy policy makers in decision problems involving the selection and classification of wind sites. A midpoint sectionalized technique has been developed to calculate the Incremental Peak Load Carrying Capability (IPLCC) and to assess the LCCBR and ECR. The technique is effective and usually takes only a few iterations to obtain the indices. Sequential Monte Carlo simulation is utilized to estimate the adequacy of a generating system including WECS. A small reliability test system containing WECS is utilized to illustrate the proposed technique.

  14. Pedicle viability as the determinant factor for conversion to free nipple graft

    PubMed Central

    Al-shaham, AA

    2010-01-01

    INTRODUCTION: Women with extremely large breasts have many complaints. Reduction mammaplasty improves shape and relieves physical symptoms and alleviates psychological complaints. Mammaplasty is a an evolving technique; no single method is ideal or suitable for all breasts. Many techniques are advocated for reduction mammaplasty, including the superior, vertical, horizontal, lateral and inferior (the most popular) pedicle techniques. Even after 60 years of development in breast reduction techniques, there are still reported incidences of nipple-areola complex (NAC) necrosis. OBJECTIVE: To assess the perioperative conversion to free nipple graft to prevent the complication of nipple necrosis when pedicle viability is grossly compromised. METHODS: Between January 2002 and March 2006, 66 patients (132 breasts) underwent reduction mammaplasty using the inferior pedicle technique. The patients presented with breast gigantism and required excision of more than 1000 g of breast tissue per side. The mean patient age was 34.81 years. Patients had neck, shoulder and back pain as well as psychological complaints. Data regarding sternal notch-to-nipple distances and inframammary fold-to-nipple distances were recorded preoperatively and postoperatively. The weights of the excised breast tissue from either side were recorded. Viability of the pedicle flap was carefully monitored through perioperative clinical observation of skin colour, temperature, capillary refill and bleeding characteristics, and reassessed after pedicle folding and placement inside the newly tailored skin envelope. Nonvital NAC, as evaluated by the surgeon during surgery, necessitated conversion to the free nipple graft technique. RESULTS: During the course of the study, two patients (four breasts; 3.03%) exhibited impending gangrene to the NAC, and perioperative conversion to the free nipple graft was performed. In these two patients, the pedicle length ranged from 23 cm to 25 cm, and breast mass reduction

  15. [Contributions by Conversation Analysis to healthcare studies: reflections based on patients' attributions].

    PubMed

    Ostermann, Ana Cristina; de Souza, Joseane

    2009-07-01

    This study is part of a larger research project aimed at investigating physician-patient interactions in women's health. In this article, by looking at naturalistic data, which consists of 144 fully transcribed audio recordings of face-to-face interactions between gynecologists/obstetricians and female patients, we propose to: (1) present the theoretical and methodological approach of Conversation Analysis to health studies in Brazil; (2) discuss how Conversation Analysis can reveal how 'macro' questions (e.g. National Policy for the Humanization of Healthcare) are (or are not) translated into interactional practices at the 'micro' level and, thus, emphasize the issues of language and communication, only briefly discussed in the HumanizaSUS documents; and (3) analyze how a specific interactional phenomenon, 'attribution' (i.e. voluntary explanations about the possible causes of their problems), might describe ordinary and concrete humanization practices in healthcare services. PMID:19578573

  16. Functional Analysis of Transcription Factors in Arabidopsis

    PubMed Central

    Mitsuda, Nobutaka; Ohme-Takagi, Masaru

    2009-01-01

    Transcription factors (TFs) regulate the expression of genes at the transcriptional level. Modification of TF activity dynamically alters the transcriptome, which leads to metabolic and phenotypic changes. Thus, functional analysis of TFs using ‘omics-based’ methodologies is one of the most important areas of the post-genome era. In this mini-review, we present an overview of Arabidopsis TFs and introduce strategies for the functional analysis of plant TFs, which include both traditional and recently developed technologies. These strategies can be assigned to five categories: bioinformatic analysis; analysis of molecular function; expression analysis; phenotype analysis; and network analysis for the description of entire transcriptional regulatory networks. PMID:19478073

  17. PROJECTED PRINCIPAL COMPONENT ANALYSIS IN FACTOR MODELS

    PubMed Central

    Fan, Jianqing; Liao, Yuan; Wang, Weichen

    2016-01-01

    This paper introduces a Projected Principal Component Analysis (Projected-PCA), which employees principal component analysis to the projected (smoothed) data matrix onto a given linear space spanned by covariates. When it applies to high-dimensional factor analysis, the projection removes noise components. We show that the unobserved latent factors can be more accurately estimated than the conventional PCA if the projection is genuine, or more precisely, when the factor loading matrices are related to the projected linear space. When the dimensionality is large, the factors can be estimated accurately even when the sample size is finite. We propose a flexible semi-parametric factor model, which decomposes the factor loading matrix into the component that can be explained by subject-specific covariates and the orthogonal residual component. The covariates’ effects on the factor loadings are further modeled by the additive model via sieve approximations. By using the newly proposed Projected-PCA, the rates of convergence of the smooth factor loading matrices are obtained, which are much faster than those of the conventional factor analysis. The convergence is achieved even when the sample size is finite and is particularly appealing in the high-dimension-low-sample-size situation. This leads us to developing nonparametric tests on whether observed covariates have explaining powers on the loadings and whether they fully explain the loadings. The proposed method is illustrated by both simulated data and the returns of the components of the S&P 500 index. PMID:26783374

  18. Review and analysis of the 1980-1989 biomass thermochemical conversion program

    NASA Astrophysics Data System (ADS)

    Stevens, D. J.

    1994-09-01

    In the period between 1980 and 1989, the U.S. Department of Energy (DOE) sponsored research and development projects through its Biomass Thermochemical Conversion (BTC) Program. Thermochemical conversion technologies use elevated temperatures to convert biomass into more useful forms of energy such as fuel gases or transportation fuels. The BTC Program included a wide range of biomass conversion projects in the areas of gasification, pyrolysis, liquefaction, and combustion. This work formed the basis of the present DOE research and development efforts on advanced liquid fuel and power generation systems. At the beginning of Fiscal Year 1989, the management of the BTC Program was transferred from Pacific Northwest Laboratory (PNL) to National Renewable Energy Laboratory (NREL, formerly Solar Energy Research Institute). This document presents a summary of the research which was performed under the BTC Program during the 1981-1989 time frame. The document consists of an analysis of the research projects which were funded by the BTC Program and a bibliography of published documents. This work will help ensure that information from PNL's BTC Program is available to those interested in biomass conversion technologies. The background of the BTC Program is discussed in the first chapter of this report. In addition, a brief summary of other related biomass research and development programs funded by the U.S. Department of Energy and others is presented with references where additional information can be found. The remaining chapters of the report present a detailed summary of the research projects which were funded by the BTC Program. The progress which was made on each project is summarized, the overall impact on biomass conversion is discussed, and selected references are provided.

  19. Review and analysis of the 1980-1989 biomass thermochemical conversion program

    SciTech Connect

    Stevens, D.J.

    1994-09-01

    In the period between 1980 and 1989, the U.S. Department of Energy (DOE) sponsored research and development projects through its Biomass Thermochemical Conversion (BTC) Program. Thermochemical conversion technologies use elevated temperatures to convert biomass into more useful forms of energy such as fuel gases or transportation fuels. The BTC Program included a wide range of biomass conversion projects in the areas of gasification, pyrolysis, liquefaction, and combustion. This work formed the basis of the present DOE research and development efforts on advanced liquid fuel and power generation systems. At the beginning of Fiscal Year 1989, the management of the BTC Program was transferred from Pacific Northwest Laboratory (PNL) to National Renewable Energy Laboratory (NREL, formerly Solar Energy Research Institute). This document presents a summary of the research which was performed under the BTC Program during the 1981-1989 time frame. The document consists of an analysis of the research projects which were funded by the BTC Program and a bibliography of published documents. This work will help ensure that information from PNL`s BTC Program is available to those interested in biomass conversion technologies. The background of the BTC Program is discussed in the first chapter of this report. In addition, a brief summary of other related biomass research and development programs funded by the U.S. Department of Energy and others is presented with references where additional information can be found. The remaining chapters of the report present a detailed summary of the research projects which were funded by the BTC Program. The progress which was made on each project is summarized, the overall impact on biomass conversion is discussed, and selected references are provided.

  20. Exploring the Use of Critical Incident Analysis and the Professional Learning Conversation in an Initial Teacher Education Programme

    ERIC Educational Resources Information Center

    Harrison, Jennifer K.; Lee, Ruth

    2011-01-01

    This study focuses on critical incident analysis in initial teacher education and the part played by the professional learning conversation. A reflection framework was used to identify changes in levels of reflective practice. Conversational skills of the supervising teacher in recognising the "person" in the student teacher, and their management…

  1. A Comparison of Monotonicity Analysis with Factor Analysis

    ERIC Educational Resources Information Center

    Bentler, P. M.

    1970-01-01

    Factor analysis of artificial data is shown to yield an incorrect number of dimensions, seven, while monotonicity analysis recovered completely and accurately the fact that the data was generated from two latent dimensions. (RF)

  2. Lifetime Evaluation of Oil-immersed Power Capacitor using Conversion Factor between Model Sample and Practical Equipment

    NASA Astrophysics Data System (ADS)

    Higashiyama, Masakazu; Akiyama, Ken-Ichi; Maeda, Teruhiko; Nakamura, Shuhei; Umemura, Hiro; Hikita, Masayuki

    In this paper, the lifetime estimation method was discussed in view of Weibull distribution. For the case of power capacitor, the conversion factor between model specimen and practical equipment can be calculated by using the ratio of the electrode edge length of them and the Weibull shape parameter of the normalized V-t data obtained from the model samples. The actual failure rate of the power capacitor with PP film/capacitor-paper composite dielectric system was found to agree well with the estimated failure rate from the model samples.

  3. Systems analysis research for energy conversion and utilization technologies (ECUT). FY 1985 annual report

    SciTech Connect

    Eberhardt, J.J.; Gunn, M.E.; Levinson, T.M.

    1985-11-01

    This Annual Report highlights ECUT accomplishments in the Systems Analysis Project for FY 1985. The Systems Analysis Project was established in 1980 along with the ECUT Division. The Systems Analysis mission is to identify, analyze, and assess R and D needs and research program strategies for advanced conservation technologies. The PNL Systems Analysis staff conducts topical research, provides technical studies, and plans program activities in three areas related to energy conversion and utilization technologies: (1) technology assessment, (2) engineering analysis, and (3) project evaluation and review. This report summarizes the technical results and accomplishments of the FY 1985 projects. They relate mostly to tribology, improved ctalysts, regenerative heat exchangers, robotics and electronics industries, and bioprocessing.

  4. Using Factor Analysis To Organize Student Services.

    ERIC Educational Resources Information Center

    Majors, Mark S.; Sedlacek, William E.

    2001-01-01

    Exploratory factor analysis (EFA) was used to provide an organizational framework for data collected from an entering class of students (N=1,912). Results from the EFA indicated that items on surveys could be grouped into dimensions that can be used to plan student services. Factors that emerged included: Religion/Spirituality, Help Seeking,…

  5. Surface analysis of mixed-conducting ferrite membranes by the conversion-electron Moessbauer spectroscopy

    SciTech Connect

    Waerenborgh, J.C.; Tsipis, E.V.; Yaremchenko, A.A.; Kharton, V.V.

    2011-09-15

    Conversion-electron Moessbauer spectroscopy analysis of iron surface states in the dense ceramic membranes made of {sup 57}Fe-enriched SrFe{sub 0.7}Al{sub 0.3}O{sub 3-{delta}} perovskite, shows no traces of reductive decomposition or carbide formation in the interfacial layers after operation under air/CH{sub 4} gradient at 1173 K, within the limits of experimental uncertainty. The predominant trivalent state of iron cations at the membrane permeate-side surface exposed to flowing dry methane provides evidence of the kinetic stabilization mechanism, which is only possible due to slow oxygen-exchange kinetics and enables long-term operation of the ferrite-based ceramic reactors for natural gas conversion. At the membrane feed-side surface exposed to air, the fractions of Fe{sup 4+} and Fe{sup 3+} are close to those in the powder equilibrated at atmospheric oxygen pressure, suggesting that the exchange limitations to oxygen transport are essentially localized at the partially reduced surface. - Graphical Abstract: Conversion-electron Moessbauer spectroscopy analysis of dense ceramic membranes made of {sup 57}Fe-enriched SrFe{sub 0.7}Al{sub 0.3}O{sub 3-{delta}} perovskite, shows no reductive decomposition in thin interfacial layers after testing under air/CH{sub 4} gradient, enabling stable operation of the ferrite-based ceramic reactors for partial oxidation of methane. Highlights: > Conversion-electron Moessbauer spectroscopy is used for mixed-conducting membranes. > No decomposition is detected in the membrane surface layers under air/CH{sub 4} gradient. > Due to kinetic stabilization, Fe{sup 3+} states prevail at the surface exposed to methane. > Transmission Moessbauer spectra show perovskite decomposition on equlibration in CH{sub 4}. > Ferrite-based ceramic reactors can stably operate under air/CH{sub 4} gradient.

  6. Plot-scale testing and sensitivity analysis of Be7 based soil erosion conversion models

    NASA Astrophysics Data System (ADS)

    Taylor, Alex; Abdelli, Wahid; Barri, Bashar Al; Iurian, Andra; Gaspar, Leticia; Mabit, Lionel; Millward, Geoff; Ryken, Nick; Blake, Will

    2016-04-01

    Over the past 2 decades, a growing number of studies have recognised the potential for short-lived cosmogenic Be-7 (half-life 53 days) to be used as a tracer to evaluate soil erosion from short-term inter-rill erosion to hillslope sediment budgets. While conversion modelling approaches are now established for event-scale and extended-time-series applications, there is a lack of validation and sensitivity analysis to underpin confidence in their use across a full range of agro-climatic zones. This contribution aims to close this gap in the context of the maritime temperate climate of southwest UK. Two plots of 4 x 35 m were ploughed and tilled at the beginning of winter 2013/2014 in southwest UK to create (1) a bare, sloped soil surface and (2) a bare flat reference site. The bounded lower edge of the plot fed into a collection bin for overland flow and associated sediment. The tilled surface had a low bulk density and high permeability at the start of the experiment (ksat > 100 mm/hr). Hence, despite high rainfall in December (200 mm), notable overland flow was observed only after intense rain storms during late 2013 and early January 2014 when the soil profile was saturated i.e. driven by Saturation Overland Flow (SOF). At the time of SOF initiation, ca. 70% of the final Be-7 inventory had been delivered to the site. Subsequent to a series SOF events across a 1 month period, the plot soil surface was intensively sampled to quantify Be-7 inventory patterns and develop a tracer budget. Captured eroded sediment was dried, weighed and analysed for Be-7. All samples were analysed for particle size by laser granulometry. Be-7 inventory data were converted to soil erosion estimates using (1) standard profile distribution model, (2) the extended time series distribution model and (3) a new 'antecedent rainfall' extended time series model to account for lack of soil erosion prior to soil saturation. Results were scaled up to deliver a plot-scale sediment budget to include

  7. Starting the Conversation: An Exploratory Study of Factors That Influence Student Office Hour Use

    ERIC Educational Resources Information Center

    Griffin, Whitney; Cohen, Steven D.; Berndtson, Rachel; Burson, Kristen M.; Camper, K. Martin; Chen, Yujie; Smith, Margaret Austin

    2014-01-01

    As part of best practices for increasing faculty-student interaction, higher education institutions across the country require faculty members to hold office hours. Various studies have reported factors affecting student use of office hours; however, results are unclear at best and in some cases conflicting with respect to which factors matter…

  8. The UTRC wind energy conversion system performance analysis for horizontal axis wind turbines (WECSPER)

    NASA Technical Reports Server (NTRS)

    Egolf, T. A.; Landgrebe, A. J.

    1981-01-01

    The theory for the UTRC Energy Conversion System Performance Analysis (WECSPER) for the prediction of horizontal axis wind turbine performance is presented. Major features of the analysis are the ability to: (1) treat the wind turbine blades as lifting lines with a prescribed wake model; (2) solve for the wake-induced inflow and blade circulation using real nonlinear airfoil data; and (3) iterate internally to obtain a compatible wake transport velocity and blade loading solution. This analysis also provides an approximate treatment of wake distortions due to tower shadow or wind shear profiles. Finally, selected results of internal UTRC application of the analysis to existing wind turbines and correlation with limited test data are described.

  9. 76 FR 52539 - Federal Employees' Retirement System; Present Value Conversion Factors for Spouses of Deceased...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-08-23

    ...The Office of Personnel Management (OPM) is issuing an interim rule to revise the table of reduction factors for early commencing dates of survivor annuities for spouses of separated employees who die before the date on which they would be eligible for unreduced deferred annuities, and to revise the annuity factor for spouses of deceased employees who die in service when those spouses elect to......

  10. 76 FR 55213 - Technical Amendments to Federal Employees' Retirement System; Present Value Conversion Factors...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-07

    ... Federal Register on August 23, 2011, (76 FR 52539) revising the factor at 5 CFR 843.309(b)(2) used to convert a lump sum basic employee death benefit under 5 U.S.C. 8442(b) to 36 installment payments. That... August 23, 2011, (76 FR 52539) that changed the factor at 5 CFR 843.309(b)(2) used to convert a lump...

  11. Laparoscopic cholecystectomy--can conversion be predicted?

    PubMed

    Sikora, S S; Kumar, A; Saxena, R; Kapoor, V K; Kaushik, S P

    1995-01-01

    The possibility of conversion to open cholecystectomy (OC) always exists while performing a laparoscopic cholecystectomy (LC). This study has been performed with the aim of identifying factors predicting conversion to OC. From October 1992-April 1994, LC was attempted in 150 patients and conversion to OC was required in 29 (19%) patients. Ten preoperative factors were analyzed retrospectively to identify parameters significantly correlating with conversion to OC. Preoperative factors analyzed were age, sex, duration of symptoms, BMI (Body Mass Index), past history of jaundice, previous abdominal surgery, associated medical risk factors, palpable lump on clinical examination, USG, and OCG findings. Univariate and multiple stepwise regression analysis identified male sex, USG finding of contracted/thick-walled gall bladder, and a palpable gall bladder lump on examination as significant preoperative factors predicting conversion to OC. PMID:8553679

  12. A note on variational Bayesian factor analysis.

    PubMed

    Zhao, Jian-hua; Yu, Philip L H

    2009-09-01

    Existing works on variational bayesian (VB) treatment for factor analysis (FA) model such as [Ghahramani, Z., & Beal, M. (2000). Variational inference for Bayesian mixture of factor analysers. In Advances in neural information proceeding systems. Cambridge, MA: MIT Press; Nielsen, F. B. (2004). Variational approach to factor analysis and related models. Master's thesis, The Institute of Informatics and Mathematical Modelling, Technical University of Denmark.] are found theoretically and empirically to suffer two problems: (1) penalize the model more heavily than BIC and (2) perform unsatisfactorily in low noise cases as redundant factors can not be effectively suppressed. A novel VB treatment is proposed in this paper to resolve the two problems and a simulation study is conducted to testify its improved performance over existing treatments. PMID:19135337

  13. Scene kinetics mitigation using factor analysis with derivative factors.

    SciTech Connect

    Larson, Kurt W.; Melgaard, David Kennett; Scholand, Andrew Joseph

    2010-07-01

    Line of sight jitter in staring sensor data combined with scene information can obscure critical information for change analysis or target detection. Consequently before the data analysis, the jitter effects must be significantly reduced. Conventional principal component analysis (PCA) has been used to obtain basis vectors for background estimation; however PCA requires image frames that contain the jitter variation that is to be modeled. Since jitter is usually chaotic and asymmetric, a data set containing all the variation without the changes to be detected is typically not available. An alternative approach, Scene Kinetics Mitigation, first obtains an image of the scene. Then it computes derivatives of that image in the horizontal and vertical directions. The basis set for estimation of the background and the jitter consists of the image and its derivative factors. This approach has several advantages including: (1) only a small number of images are required to develop the model, (2) the model can estimate backgrounds with jitter different from the input training images, (3) the method is particularly effective for sub-pixel jitter, and (4) the model can be developed from images before the change detection process. In addition the scores from projecting the factors on the background provide estimates of the jitter magnitude and direction for registration of the images. In this paper we will present a discussion of the theoretical basis for this technique, provide examples of its application, and discuss its limitations.

  14. Direct conversion of mouse and human fibroblasts to functional melanocytes by defined factors.

    PubMed

    Yang, Ruifeng; Zheng, Ying; Li, Ling; Liu, Shujing; Burrows, Michelle; Wei, Zhi; Nace, Arben; Herlyn, Meenhard; Cui, Rutao; Guo, Wei; Cotsarelis, George; Xu, Xiaowei

    2014-01-01

    Direct reprogramming provides a fundamentally new approach for the generation of patient-specific cells. Here, by screening a pool of candidate transcription factors, we identify that a combination of the three factors, MITF, SOX10 and PAX3, directly converts mouse and human fibroblasts to functional melanocytes. Induced melanocytes (iMels) activate melanocyte-specific networks, express components of pigment production and delivery system and produce melanosomes. Human iMels properly integrate into the dermal-epidermal junction and produce and deliver melanin pigment to surrounding keratinocytes in a 3D organotypic skin reconstruct. Human iMels generate pigmented epidermis and hair follicles in skin reconstitution assays in vivo. The generation of iMels has important implications for studies of melanocyte lineage commitment, pigmentation disorders and cell replacement therapies. PMID:25510211

  15. Direct conversion of mouse and human fibroblasts to functional melanocytes by defined factors

    PubMed Central

    Yang, Ruifeng; Zheng, Ying; Li, Ling; Liu, Shujing; Burrows, Michelle; Wei, Zhi; Nace, Arben; Herlyn, Meenhard; Cui, Rutao; Guo, Wei; Cotsarelis, George; Xu, Xiaowei

    2015-01-01

    Direct reprogramming provides a fundamentally new approach for the generation of patient-specific cells. Here, by screening a pool of candidate transcription factors, we identify that a combination of three factors, MITF, SOX10 and PAX3, directly converts mouse and human fibroblasts to functional melanocytes. Induced melanocytes (iMels) activate melanocyte-specific networks, express components of pigment production and delivery system, and produce melanosomes. Human iMels properly integrate into the dermal-epidermal junction, and produce and deliver melanin pigment to surrounding keratinocytes in a 3D organotypic skin reconstruct. Human iMels generate pigmented epidermis and hair follicles in skin reconstitution assays in vivo. The generation of iMels has important implications for studies of melanocyte lineage commitment, pigmentation disorders and cell replacement therapies. PMID:25510211

  16. On the use of quality factors and fluence to dose rate conversion in human radiation exposures

    NASA Technical Reports Server (NTRS)

    Sondhaus, C. A.

    1972-01-01

    It is shown that various combinations of numbers and factors arrive at estimates of dose and dose effectiveness from values of fluence; but as yet it has not been possible to use biological data with the same degree of precision to estimate the physical data. It would seem that the most reasonable way to use the human data that exist is to apply them as far as possible to the human animal as a whole.

  17. Sample Dilution and Bacterial Community Composition Influence Empirical Leucine-to-Carbon Conversion Factors in Surface Waters of the World's Oceans

    PubMed Central

    Hernando-Morales, Víctor; Cornejo-Castillo, Francisco M.; Alonso-Sáez, Laura; Sarmento, Hugo; Valencia-Vila, Joaquín; Serrano Catalá, Teresa; Hernández-Ruiz, Marta; Varela, Marta M.; Ferrera, Isabel; Gutiérrez Morán, Xosé Anxelu; Gasol, Josep M.

    2015-01-01

    The transformation of leucine incorporation rates to prokaryotic carbon production rates requires the use of either theoretical or empirically determined conversion factors. Empirical leucine-to-carbon conversion factors (eCFs) vary widely across environments, and little is known about their potential controlling factors. We conducted 10 surface seawater manipulation experiments across the world's oceans, where the growth of the natural prokaryotic assemblages was promoted by filtration (i.e., removal of grazers [F treatment]) or filtration combined with dilution (i.e., also relieving resource competition [FD treatment]). The impact of sunlight exposure was also evaluated in the FD treatments, and we did not find a significant effect on the eCFs. The eCFs varied from 0.09 to 1.47 kg C mol Leu−1 and were significantly lower in the FD than in the F samples. Also, changes in bacterial community composition during the incubations, as assessed by automated ribosomal intergenic spacer analysis (ARISA), were more pronounced in the FD than in the F treatments, compared to unmanipulated controls. Thus, we discourage the common procedure of diluting samples (in addition to filtration) for eCF determination. The eCFs in the filtered treatment were negatively correlated with the initial chlorophyll a concentration, picocyanobacterial abundance (mostly Prochlorococcus), and the percentage of heterotrophic prokaryotes with high nucleic acid content (%HNA). The latter two variables explained 80% of the eCF variability in the F treatment, supporting the view that both Prochlorococcus and HNA prokaryotes incorporate leucine in substantial amounts, although this results in relatively low carbon production rates in the oligotrophic ocean. PMID:26407885

  18. Pluripotent Conversion of Muscle Stem Cells Without Reprogramming Factors or Small Molecules.

    PubMed

    Bose, Bipasha; Shenoy P, Sudheer

    2016-02-01

    Muscle derived stem cells (MDSCs) are multipotent stem cells that can differentiate into several lineages including skeletal muscle precursor cells. Here, we show that MDSCs from myostatin null mice (Mstn (-/-) ) can be readily induced into pluripotent stem cells without using reprogramming factors. Microarray studies revealed a strong upregulation of markers like Leukemia Inhibitory factor (LIF) and Leukemia Inhibitory factor receptor (LIFR) in Mstn (-/-) MDSCs as compared to wild type MDSCs (WT-MDSCs). Furthermore when cultured in mouse embryonic stem cell media with LIF for 95 days, Mstn (-/-) MDSCs formed embryonic stem cell (ES) like colonies. We termed such ES like cells as the culture-induced pluripotent stem cells (CiPSC). CiPSCs from Mstn (-/-) MDSCs were phenotypically similar to ESCs, expressed high levels of Oct4, Nanog, Sox2 and SSEA-1, maintained a normal karyotype. Furthermore, CiPSCs formed embryoid bodies and teratomas when injected into immunocompromised mice. In addition, CiPSCs differentiated into somatic cells of all three lineages. We further show that culturing in ES cell media, resulted in hypermethylation and downregulation of BMP2 in Mstn(-/-) MDSCs. Western blot further confirmed a down regulation of BMP2 signaling in Mstn (-/-) MDSCs in supportive of pluripotent reprogramming. Given that down regulation of BMP2 has been shown to induce pluripotency in cells, we propose that lack of myostatin epigenetically reprograms the MDSCs to become pluripotent stem cells. Thus, here we report the successful establishment of ES-like cells from adult stem cells of the non-germline origin under culture-induced conditions without introducing reprogramming genes. PMID:26358783

  19. DETERMINATION OF IN-VITRO LUNG SOLUBILITY AND INTAKE-TO-DOSE CONVERSION FACTOR FOR TRITIATED LANTHANUM NICKEL ALUMINUM ALLOY

    SciTech Connect

    Farfan, E.; Labone, T.; Staack, G.; Cheng, Y.; Zhou, Y.; Varallo, T.

    2011-11-11

    A sample of tritiated lanthanum nickel aluminum alloy (LaNi4.25Al0.75 or LANA.75) similar to that used at the Savannah River Site Tritium Facilities was analyzed to estimate the particle size distribution of this metal tritide powder and the rate, at which this material dissolves in the human respiratory tract after it is inhaled. This information is used to calculate the committed effective dose received by a worker after inhaling the material. These doses, which were calculated using the same methodology given in the DOE Tritium Handbook, are presented as inhalation intake-to-dose conversion factors (DCF). The DCF for this metal tritide is less than the DCF for tritiated water and radiation worker bioassay programs designed for tritiated water are adequate to monitor for intakes of this material.

  20. Cost-effectiveness analysis of TxDOT CNG fleet conversion, volume 2

    NASA Astrophysics Data System (ADS)

    Euritt, M. A.; Taylor, D. B.; Mahmassani, H.

    1992-08-01

    Increased emphasis on energy efficiency and air quality has resulted in a number of state and federal initiatives examining the use of alternative fuels for motor vehicles. Texas' program for alternate fuels includes compressed natural gas (CNG). Based on an analysis of 30-year life-cycle costs, development of a natural gas vehicle (NGV) program for the Texas Department of Transportation (TxDOT) would cost about $47 million (in 1991 dollars). These costs include savings from lower priced natural gas, infrastructure costs for a fast-fueling station, vehicle costs, and operating costs. The 30-year life-cycle costs translate into an average annual vehicle cost increase of $596, or about 4.9 cents more per vehicle mile of travel. Based on the cost-effectiveness analysis and assumptions, there are currently no TxDOT stations suitable for conversion to compressed natural gas.

  1. Plasma to egg conversion factor for evaluating polychlorinated biphenyl and DDT exposures in great horned owls and bald eagles.

    PubMed

    Strause, Karl D; Zwiernik, Matthew J; Im, Sook Hyeon; Newsted, John L; Kay, Denise P; Bradley, Patrick W; Blankenship, Alan L; Williams, Lisa L; Giesy, John P

    2007-07-01

    The benefits of nondestructive sampling techniques, such as plasma sampling, to directly measure contaminant exposure levels in at-risk or protected raptor populations are many. However, such assays are generally inconsistent with the most certain source of toxicity reference values, which are based on feeding studies and quantified as dietary or "in ovo" (egg-based) concentrations. An accurate conversion factor to translate nondestructive plasma-based contaminant concentrations to comparable egg-based concentrations will prove valuable to risk assessors investigating the potential effects of chemical exposures to raptors. We used databases describing the concentrations of total polychlorinated biphenyls (PCBs) in great horned owls (GHO; Bubo virginianus) and total PCBs and p,p'-dichlorodiphenyldichloroethylene (p,p'-DDE) in bald eagles (Haliaeetus leucocephalus) from the Great Lakes region (Michigan, Wisconsin, USA) to develop a relationship to predict concentrations of PCBs and DDE in eggs. To develop a robust predictive relationship, all of the source data included concentrations of both total PCBs and/or DDE for nestling blood plasma and egg samples collected from within discrete active nesting territories and, in most instances, the same nest. The key characteristics (slope and elevation) of each relationship were tested for differences related to species and geographic region. Predicted variability of relationships were examined and compared to variability associated with natural systems. The results of statistical testing indicate that applying the conversion factors between species (GHO to bald eagle) and among geographic regions yields predicted egg concentrations that are not statistically dissimilar and are within the natural variability observed for residue concentrations among eggs of raptors within species and region. PMID:17665679

  2. Lineage conversion induced by pluripotency factors involves transient passage through an iPS cell stage

    PubMed Central

    Bar-Nur, Ori; Verheul, Cassandra; Sommer, Andreia Gianotti; Brumbaugh, Justin; Schwarz, Benjamin A.; Lipchina, Inna; Huebner, Aaron J.; Mostoslavsky, Gustavo; Hochedlinger, Konrad

    2016-01-01

    Brief expression of pluripotency-associated factors such as Oct4, Klf4, Sox2 and c-Myc (OKSM), in combination with differentiation-inducing signals, was reported to trigger transdifferentiation of fibroblasts into other cell types. Here we show that OKSM expression in mouse fibroblasts gives rise to both induced pluripotent stem cells (iPSCs) and induced neural stem cells (iNSCs) under conditions previously shown to induce only iNSCs. Fibroblast-derived iNSC colonies silenced retroviral transgenes and reactivated silenced X chromosomes, both hallmarks of pluripotent stem cells. Moreover, lineage tracing with an Oct4-CreER labeling system demonstrated that virtually all iNSC colonies originated from cells transiently expressing Oct4, whereas ablation of Oct4+ cells prevented iNSC formation. Lastly, an alternative transdifferentiation cocktail that lacks Oct4 and was reportedly unable to support induced pluripotency yielded iPSCs and iNSCs carrying the Oct4-CreER-derived lineage label. Together, these data suggest that iNSC generation from fibroblasts using OKSM and other pluripotency-related reprogramming factors requires passage through a transient iPSC state. PMID:26098450

  3. Factor Analysis by Generalized Least Squares.

    ERIC Educational Resources Information Center

    Joreskog, Karl G.; Goldberger, Arthur S.

    Aitkin's generalized least squares (GLS) principle, with the inverse of the observed variance-covariance matrix as a weight matrix, is applied to estimate the factor analysis model in the exploratory (unrestricted) case. It is shown that the GLS estimates are scale free and asymptotically efficient. The estimates are computed by a rapidly…

  4. Heterogeneous Factor Analysis Models: A Bayesian Approach.

    ERIC Educational Resources Information Center

    Ansari, Asim; Jedidi, Kamel; Dube, Laurette

    2002-01-01

    Developed Markov Chain Monte Carlo procedures to perform Bayesian inference, model checking, and model comparison in heterogeneous factor analysis. Tested the approach with synthetic data and data from a consumption emotion study involving 54 consumers. Results show that traditional psychometric methods cannot fully capture the heterogeneity in…

  5. Exploratory Factor Analysis with Small Sample Sizes

    ERIC Educational Resources Information Center

    de Winter, J. C. F.; Dodou, D.; Wieringa, P. A.

    2009-01-01

    Exploratory factor analysis (EFA) is generally regarded as a technique for large sample sizes ("N"), with N = 50 as a reasonable absolute minimum. This study offers a comprehensive overview of the conditions in which EFA can yield good quality results for "N" below 50. Simulations were carried out to estimate the minimum required "N" for different…

  6. What Is Rotating in Exploratory Factor Analysis?

    ERIC Educational Resources Information Center

    Osborne, Jason W.

    2015-01-01

    Exploratory factor analysis (EFA) is one of the most commonly-reported quantitative methodology in the social sciences, yet much of the detail regarding what happens during an EFA remains unclear. The goal of this brief technical note is to explore what "rotation" is, what exactly is rotating, and why we use rotation when performing…

  7. A Factor Analysis of Psychotic Behavior.

    ERIC Educational Resources Information Center

    Eaves, Ronald C.; And Others

    1988-01-01

    The Psychotic Behavior Rating Scale uses a factor analysis approach to aid in differential diagnosis of autism, schizophrenia, mental retardation, aphasia, and other severe handicaps. The scale is compared with five existing qualitatively developed instruments, noting similarities and dissimilarities among the various scales. (Author/JDD)

  8. Comparing Package Programs for Factor Analysis

    ERIC Educational Resources Information Center

    Wimberley, Ronald C.

    1978-01-01

    Earlier comparisons of packaged programs for factor analysis are updated because of recent revision in some programs. The top status of SPSS is no longer so apparent as formerly. BMD and SAS now have expanded options. SAS has flexibility and convenience. (Author)

  9. Factor Analysis Applied the VFY-218 RCS Data

    NASA Technical Reports Server (NTRS)

    Woo, Alex; Chancellor, Marisa K. (Technical Monitor)

    1997-01-01

    Present statistical factor analysis of computer simulations and measurement data for the VFY-218 configuration. Factor analysis try to quantify the statistical grouping of measurements and simulations.

  10. Internal dose conversion factors for calculation of dose to the public

    SciTech Connect

    Not Available

    1988-07-01

    This publication contains 50-year committed dose equivalent factors, in tabular form. The document is intended to be used as the primary reference by the US Department of Energy (DOE) and its contractors for calculating radiation dose equivalents for members of the public, resulting from ingestion or inhalation of radioactive materials. Its application is intended specifically for such materials released to the environment during routine DOE operations, except in those instances where compliance with 40 CFR 61 (National Emission Standards for Hazardous Air Pollutants) requires otherwise. However, the calculated values may be equally applicable to unusual releases or to occupational exposures. The use of these committed dose equivalent tables should ensure that doses to members of the public from internal exposures are calculated in a consistent manner at all DOE facilities.

  11. A Linguistic Analysis of Chat Reference Conversations with 18-24 Year-Old College Students

    ERIC Educational Resources Information Center

    Maness, Jack M.

    2008-01-01

    Thirty-one chat reference conversations were linguistically analyzed, compared to twenty-three instant messaging (IM) conversations held between students, and further correlated to students' satisfaction with the reference interaction. Conversations between librarians and students in chat reference are more formal than those solely involving…

  12. Correction factor for hair analysis by PIXE

    NASA Astrophysics Data System (ADS)

    Montenegro, E. C.; Baptista, G. B.; De Castro Faria, L. V.; Paschoa, A. S.

    1980-01-01

    The application of the Particle Induced X-ray Emission (PIXE) technique to analyse quantitatively the elemental composition of hair specimens brings about some difficulties in the interpretation of the data. The present paper proposes a correction factor to account for the effects of the energy loss of the incident particle with penetration depth, and X-ray self-absorption when a particular geometrical distribution of elements in hair is assumed for calculational purposes. The correction factor has been applied to the analysis of hair contents Zn, Cu and Ca as a function of the energy of the incident particle.

  13. Shaping the Conversation: A Secondary Analysis of Reproductive Decision-Making Among Black Mothers with HIV.

    PubMed

    Amutah, Ndidiamaka N; Gifuni, Jacqueline; Wesley, Yvonne

    2016-01-01

    The purpose of this qualitative secondary data analysis is to examine the major influencers on mothers with HIV in their childbearing decisions, as well as how those influencers shape conversations with clinicians and health-care providers regarding HIV treatment and prevention. The original study gained insight into the reproductive decision-making of mothers with HIV. By analyzing a subsample of 15 interviews from an original cohort of 25 participants in the earlier study, three major themes were identified as follows: (1) family members, not health-care providers, influence reproductive decisions; (2) negative attitudes toward subsequent pregnancies are mainly due to HIV transmission; and (3) birth control decisions were predominately supported by family members, while health-care providers were not consulted. PMID:27158227

  14. Shaping the Conversation: A Secondary Analysis of Reproductive Decision-Making Among Black Mothers with HIV

    PubMed Central

    Amutah, Ndidiamaka N.; Gifuni, Jacqueline; Wesley, Yvonne

    2016-01-01

    The purpose of this qualitative secondary data analysis is to examine the major influencers on mothers with HIV in their childbearing decisions, as well as how those influencers shape conversations with clinicians and health-care providers regarding HIV treatment and prevention. The original study gained insight into the reproductive decision-making of mothers with HIV. By analyzing a subsample of 15 interviews from an original cohort of 25 participants in the earlier study, three major themes were identified as follows: (1) family members, not health-care providers, influence reproductive decisions; (2) negative attitudes toward subsequent pregnancies are mainly due to HIV transmission; and (3) birth control decisions were predominately supported by family members, while health-care providers were not consulted. PMID:27158227

  15. Electromagnetic Spectrum Analysis and Its Influence on the Photoelectric Conversion Efficiency of Solar Cells.

    PubMed

    Hu, Kexiang; Ding, Enjie; Wangyang, Peihua; Wang, Qingkang

    2016-06-01

    The electromagnetic spectrum and the photoelectric conversion efficiency of the silicon hexagonal nanoconical hole (SiHNH) arrays based solar cells is systematically analyzed according to Rigorous Coupled Wave Analysis (RCWA) and Modal Transmission Line (MTL) theory. An ultimate efficiency of the optimized SiHNH arrays based solar cell is up to 31.92% in consideration of the absorption spectrum, 4.52% higher than that of silicon hexagonal nanoconical frustum (SiHNF) arrays. The absorption enhancement of the SiHNH arrays is due to its lower reflectance and more supported guided-mode resonances, and the enhanced ultimate efficiency is insensitive to bottom diameter (D(bot)) of nanoconical hole and the incident angle. The result provides an additional guideline for the nanostructure surface texturing fabrication design for photovoltaic applications. PMID:27427668

  16. For the sake of whom: conversation analysis of advice giving in offender counseling.

    PubMed

    Jing-ying, Guo

    2013-08-01

    Regarded as beneficial and preferable to the clients, advice delivery has been an integral part of counseling; however, there are controversies over the suitability of giving advice in counseling services, including counseling conducted in the context of prisons. Based on conversation analysis, this article tries to explore when and how police counselors in two Chinese prisons give advice and how inmate clients respond to and seek advice in offender counseling. It is found that advice delivery, supposed to be for the inmate clients' sake, only serves a phatic function in the context of prisons in which security is a priority, and transforming inmates into law-abiding citizen is the overall goal of prison rehabilitation and correction. Hence, offender counselors, intending to alleviate depression and anxiety in inmate clients, are caught in a dilemma. PMID:22573711

  17. Inflexibility as an interactional phenomenon: Using conversation analysis to re-examine a symptom of autism.

    PubMed

    Muskett, Tom; Perkins, Mick; Clegg, Judy; Body, Richard

    2010-01-01

    Many accounts of autism spectrum disorder (ASD) imply that the condition's behavioural 'symptoms' are direct reflexes of underlying deficits. In doing so, however, they invariably overlook the social contexts in which symptomatic behaviours occur and are identified as pathological. This study addresses this issue, using conversation analysis (CA) to examine the emergence of inflexibility, a behavioural trait symptomatic of ASD, during play involving an adult and diagnosed child. We argue that 'inflexibility' is the product of the child's strategic attempts to retain control over the unfolding interaction, within a context where such attempts breach normative expectations about adult-child play. Furthermore, it demonstrates that the adult does not resist these attempts, on occasion even explicitly providing opportunity for subsequent inflexibility. This challenges the assumption that ASD's behavioural profile solely represents the endpoint of underlying deficit, and demonstrates how 'non-impaired' speakers can be implicated in the manifestation of symptomatic behaviours. PMID:20030550

  18. Conversion factors for determining organ doses received by paediatric patients in high-resolution single slice computed tomography with narrow collimation.

    PubMed

    Seidenbusch, Michael C; Harder, Dietrich; Regulla, Dieter F; Schneider, Karl

    2014-05-01

    Estimations of organ doses DT received during computed tomographic examinations are usually performed by applying conversion factors to basic dose indicators like the computed tomography dose index (CTDI) or the dose-length-product (DLP). In addition to the existing conversion factors for beam apertures of 5 mm or 10 mm, we present new DLP-DT conversion factors adapted to high-resolution CT (HRCT) examinations of infants and young children with beam apertures of the order of 1 mm and under consideration of bow tie filtration. Calculations are performed on mathematical MIRD phantoms for an age range from 0, 1, 5, 10, 15 up to (for comparison) 30 years by adapting PCXMC, a Monte Carlo algorithm originally developed by STUK (Helsinki, Finland) for dose reconstructions in projection radiography. For this purpose, each single slice CT examination is approximated by a series of corresponding virtual planar radiographies comprising all focus positions. The transformation of CT exposure parameters into exposure parameters of the series of corresponding planar radiographies is performed by a specially developed algorithm called XCT. The DLP values are evaluated using the EGSRay code. The new method is verified at a beam aperture of 10 mm by comparison with formerly published conversion factors. We show that the higher spatial resolution leads to an enhanced DLP-DT conversion factor if a small organ (e. g. thyroid gland, mammae, uterus, ovaries, testes) is exactly met by the chosen CT slice, while the conversion factor is drastically reduced if the chosen CT slice is positioned above or below the organ. This effect is utilized for dose-saving examinations with only a few single slices instead a full scan, which technique is applied in about 10% of all paediatric chest CT examinations. PMID:24630933

  19. Deep Learning with Hierarchical Convolutional Factor Analysis

    PubMed Central

    Chen, Bo; Polatkan, Gungor; Sapiro, Guillermo; Blei, David; Dunson, David; Carin, Lawrence

    2013-01-01

    Unsupervised multi-layered (“deep”) models are considered for general data, with a particular focus on imagery. The model is represented using a hierarchical convolutional factor-analysis construction, with sparse factor loadings and scores. The computation of layer-dependent model parameters is implemented within a Bayesian setting, employing a Gibbs sampler and variational Bayesian (VB) analysis, that explicitly exploit the convolutional nature of the expansion. In order to address large-scale and streaming data, an online version of VB is also developed. The number of basis functions or dictionary elements at each layer is inferred from the data, based on a beta-Bernoulli implementation of the Indian buffet process. Example results are presented for several image-processing applications, with comparisons to related models in the literature. PMID:23787342

  20. Analysis of the acoustic conversion efficiency for infrasound from atmospheric entry of NEO`s

    SciTech Connect

    Whitaker, R.W.; ReVelle, D.O.

    1996-02-01

    ReVelle (1995) has recently presented a summary of available infrasonic signals from near earth objects (NEO`s) that entered the earth`s atmosphere between 1960-1980. We will analyze these signals using a formalism developed by Cox (1958) to calculate the energy of explosive sources in the atmosphere. For each source we will calculate the acoustic conversion efficiency for each source, i.e., the fraction of the original source energy that is available to couple into an acoustic wave. Based on results in Cox with conventional explosions, this quantity is expected to depend weakly on the range from the source. Since this quantity is difficult to estimate using fundamental blast wave theories, we instead use well-known, and independently calibrated, semi-empirical source energy-wave period (at maximum amplitude) scaling relations developed in the 1960-1975 period by the U.S. Air Force to determine the source energy, E{sub s}, from observations. Using E{sub s} and range to the source along with various observed signal and atmospheric properties, the efficiency can be computed, similar calculations have been done for other relevant atmospheric phenomena for low altitude sources. For example, thunder observations at relatively close range have been used by Few and co-workers to determine an acoustic conversion efficiency of about 0.4%. The only previous estimation for meteors was made by Astapovich (1946) who determined the acoustic efficiency to be less than 0.01%. By computing this efficiency factor we hope to predict the expected detection rate of large NEO`s for the proposed CTBT global scale infrasonic array systems, and to establish the rate of false alarms due to natural atmospheric explosions.

  1. Exploratory Bi-Factor Analysis: The Oblique Case

    ERIC Educational Resources Information Center

    Jennrich, Robert I.; Bentler, Peter M.

    2012-01-01

    Bi-factor analysis is a form of confirmatory factor analysis originally introduced by Holzinger and Swineford ("Psychometrika" 47:41-54, 1937). The bi-factor model has a general factor, a number of group factors, and an explicit bi-factor structure. Jennrich and Bentler ("Psychometrika" 76:537-549, 2011) introduced an exploratory form of bi-factor…

  2. Revising the Competitiveness Index using factor analysis.

    PubMed

    Houston, John; Harris, Paul; McIntire, Sandra; Francis, Dientje

    2002-02-01

    The Competitiveness Index is a 20-item true-false measure designed to assess the desire to win in interpersonal situations. To develop a more psychometrically sound form of the scale, 213 undergraduates were administered the original form and a modified version containing a 5-point Likert-type scale. An initial principal component analysis using a varimax rotation of the modified version yielded a four-factor solution accounting for 54.5% of the explained variance. Based on a subsequent reliability analysis. six items were dropped from the modified scale. A second analysis produced a two-factor solution accounting for 54.1% of the explained variance. Both factors (Enjoyment of Competition and Contentiousness) formed reliable subscales. The 14-item Revised Competitiveness Index had high internal consistency and was positively correlated with the original Competitiveness Index, the competitiveness subscales of the Work and Family Orientation Questionnaire, the Sports Orientation Questionnaire, and the Nach Naff measure of Need for Achievement. PMID:11899003

  3. A safety analysis of food waste-derived animal feeds from three typical conversion techniques in China.

    PubMed

    Chen, Ting; Jin, Yiying; Shen, Dongsheng

    2015-11-01

    This study was based on the food waste to animal feed demonstration projects in China. A safety analysis of animal feeds from three typical treatment processes (i.e., fermentation, heat treatment, and coupled hydrothermal treatment and fermentation) was presented. The following factors are considered in this study: nutritive values characterized by organoleptic properties and general nutritional indices; the presence of bovine- and sheep-derived materials; microbiological indices for Salmonella, total coliform (TC), total aerobic plate counts (TAC), molds and yeast (MY), Staphylococcus Aureus (SA), and Listeria; chemical contaminant indices for hazardous trace elements such as Cr, Cd, and As; and nitrite and organic contaminants such as aflatoxin B1 (AFB1) and hexachlorocyclohexane (HCH). The present study reveals that the feeds from all three conversion processes showed balanced nutritional content and retained a certain feed value. The microbiological indices and the chemical contaminant indices for HCH, dichlorodiphenyltrichloroethane (DDT), nitrite, and mercury all met pertinent feed standards; however, the presence of bovine- and sheep-derived materials and a few chemical contaminants such as Pb were close to or might exceed the legislation permitted values in animal feeding. From the view of treatment techniques, all feed retained part of the nutritional values of the food waste after the conversion processes. Controlled heat treatment can guarantee the inactivation of bacterial pathogens, but none of the three techniques can guarantee the absence of cattle- and sheep-derived materials and acceptable levels of certain contaminants. The results obtained in this research and the feedstuffs legislation related to animal feed indicated that food waste-derived feed could be considered an adequate alternative to be used in animal diets, while the feeding action should be changed with the different qualities of the products, such as restrictions on the application

  4. Monte Carlo calculation of flux-to-dose-rate conversion factors for energies between 0. 01 and 1. 00 MeV

    SciTech Connect

    Tapia, C.S.

    1980-12-08

    Gamma-ray flux-to-dose-rate conversion factors for energies between 0.01 and 1.0 MeV were computed using the Monte Carlo method for a 30-cm-thick slab having the standard-man composition. Agreement between the computed factors and standard factors (ANSI/ANS-6.1.1-1977) was optimal for energies above 0.1 MeV and was at most 30% lower (at 0.02 MeV) for energies below 0.1 MeV. The computed factors were also in agreement with experimentally-obtained factors.

  5. Web Conversations About Complementary and Alternative Medicines and Cancer: Content and Sentiment Analysis

    PubMed Central

    Truccolo, Ivana; Antonini, Marialuisa; Rinaldi, Fabio; Omero, Paolo; Ferrarin, Emanuela; De Paoli, Paolo; Tasso, Carlo

    2016-01-01

    Background The use of complementary and alternative medicine (CAM) among cancer patients is widespread and mostly self-administrated. Today, one of the most relevant topics is the nondisclosure of CAM use to doctors. This general lack of communication exposes patients to dangerous behaviors and to less reliable information channels, such as the Web. The Italian context scarcely differs from this trend. Today, we are able to mine and analyze systematically the unstructured information available in the Web, to get an insight of people’s opinions, beliefs, and rumors concerning health topics. Objective Our aim was to analyze Italian Web conversations about CAM, identifying the most relevant Web sources, therapies, and diseases and measure the related sentiment. Methods Data have been collected using the Web Intelligence tool ifMONITOR. The workflow consisted of 6 phases: (1) eligibility criteria definition for the ifMONITOR search profile; (2) creation of a CAM terminology database; (3) generic Web search and automatic filtering, the results have been manually revised to refine the search profile, and stored in the ifMONITOR database; (4) automatic classification using the CAM database terms; (5) selection of the final sample and manual sentiment analysis using a 1-5 score range; (6) manual indexing of the Web sources and CAM therapies type retrieved. Descriptive univariate statistics were computed for each item: absolute frequency, percentage, central tendency (mean sentiment score [MSS]), and variability (standard variation σ). Results Overall, 212 Web sources, 423 Web documents, and 868 opinions have been retrieved. The overall sentiment measured tends to a good score (3.6 of 5). Quite a high polarization in the opinions of the conversation partaking emerged from standard variation analysis (σ≥1). In total, 126 of 212 (59.4%) Web sources retrieved were nonhealth-related. Facebook (89; 21%) and Yahoo Answers (41; 9.7%) were the most relevant. In total, 94 CAM

  6. Performance analysis of fault-tolerant systems in parallel execution of conversations

    NASA Technical Reports Server (NTRS)

    Kim, K. H.; Heu, Shin; Yang, Seung M.

    1989-01-01

    The execution overhead inherent in the conversation scheme, which is a scheme for realizing fault-tolerant cooperating processes free of the domino effect, is analyzed. Multiprocessor/multicomputer systems capable of parallel execution of conversation components are considered and a queuing network model of such systems is adopted. Based on the queuing model, various performance indicators, including system throughput, average number of processors idling inside a conversation due to the synchronization required, and average time spent in the conversation, have been evaluated numerically for several application environments. The numeric results are discussed and several essential performance characteristics of the conversation scheme are derived. For example, when the number of participant processes is not large, say less than six, the system performance is highly affected by the synchronization required on the processes in a conversation, and not so much by the probability of acceptance-test failure.

  7. GACT: a Genome build and Allele definition Conversion Tool for SNP imputation and meta-analysis in genetic association studies

    PubMed Central

    2014-01-01

    Background Genome-wide association studies (GWAS) have successfully identified genes associated with complex human diseases. Although much of the heritability remains unexplained, combining single nucleotide polymorphism (SNP) genotypes from multiple studies for meta-analysis will increase the statistical power to identify new disease-associated variants. Meta-analysis requires same allele definition (nomenclature) and genome build among individual studies. Similarly, imputation, commonly-used prior to meta-analysis, requires the same consistency. However, the genotypes from various GWAS are generated using different genotyping platforms, arrays or SNP-calling approaches, resulting in use of different genome builds and allele definitions. Incorrect assumptions of identical allele definition among combined GWAS lead to a large portion of discarded genotypes or incorrect association findings. There is no published tool that predicts and converts among all major allele definitions. Results In this study, we have developed a tool, GACT, which stands for Genome build and Allele definition Conversion Tool, that predicts and inter-converts between any of the common SNP allele definitions and between the major genome builds. In addition, we assessed several factors that may affect imputation quality, and our results indicated that inclusion of singletons in the reference had detrimental effects while ambiguous SNPs had no measurable effect. Unexpectedly, exclusion of genotypes with missing rate > 0.001 (40% of study SNPs) showed no significant decrease of imputation quality (even significantly higher when compared to the imputation with singletons in the reference), especially for rare SNPs. Conclusion GACT is a new, powerful, and user-friendly tool with both command-line and interactive online versions that can accurately predict, and convert between any of the common allele definitions and between genome builds for genome-wide meta-analysis and imputation of

  8. Factor Rotation and Standard Errors in Exploratory Factor Analysis

    ERIC Educational Resources Information Center

    Zhang, Guangjian; Preacher, Kristopher J.

    2015-01-01

    In this article, we report a surprising phenomenon: Oblique CF-varimax and oblique CF-quartimax rotation produced similar point estimates for rotated factor loadings and factor correlations but different standard error estimates in an empirical example. Influences of factor rotation on asymptotic standard errors are investigated using a numerical…

  9. Accident Analysis for the NIST Research Reactor Before and After Fuel Conversion

    SciTech Connect

    Baek J.; Diamond D.; Cuadra, A.; Hanson, A.L.; Cheng, L-Y.; Brown, N.R.

    2012-09-30

    Postulated accidents have been analyzed for the 20 MW D2O-moderated research reactor (NBSR) at the National Institute of Standards and Technology (NIST). The analysis has been carried out for the present core, which contains high enriched uranium (HEU) fuel and for a proposed equilibrium core with low enriched uranium (LEU) fuel. The analyses employ state-of-the-art calculational methods. Three-dimensional Monte Carlo neutron transport calculations were performed with the MCNPX code to determine homogenized fuel compositions in the lower and upper halves of each fuel element and to determine the resulting neutronic properties of the core. The accident analysis employed a model of the primary loop with the RELAP5 code. The model includes the primary pumps, shutdown pumps outlet valves, heat exchanger, fuel elements, and flow channels for both the six inner and twenty-four outer fuel elements. Evaluations were performed for the following accidents: (1) control rod withdrawal startup accident, (2) maximum reactivity insertion accident, (3) loss-of-flow accident resulting from loss of electrical power with an assumption of failure of shutdown cooling pumps, (4) loss-of-flow accident resulting from a primary pump seizure, and (5) loss-of-flow accident resulting from inadvertent throttling of a flow control valve. In addition, natural circulation cooling at low power operation was analyzed. The analysis shows that the conversion will not lead to significant changes in the safety analysis and the calculated minimum critical heat flux ratio and maximum clad temperature assure that there is adequate margin to fuel failure.

  10. Factored interval particle filtering for gait analysis.

    PubMed

    Saboune, Jamal; Rose, Cédric; Charpillet, François

    2007-01-01

    Commercial gait analysis systems rely on wearable sensors. The goal of this study is to develop a low cost marker less human motion capture tool. Our method is based on the estimation of 3d movements using video streams and the projection of a 3d human body model. Dynamic parameters only depend on human body movement constraints. No trained gait model is used which makes this approach generic. The 3d model is characterized by the angular positions of its articulations. The kinematic chain structure allows to factor the state vector representing the configuration of the model. We use a dynamic bayesian network and a modified particle filtering algorithm to estimate the most likely state configuration given an observation sequence. The modified algorithm takes advantage of the factorization of the state vector for efficiently weighting and resampling the particles. PMID:18002684

  11. Exploratory Factor Analysis and Confirmatory Factor Analysis of the Korean Version of Hypomania Checklist-32

    PubMed Central

    An, Doyoun; Hong, Kyung Sue

    2011-01-01

    Objective The Hypomania Checklist - 32 (HCL-32) is a self-assessment instrument developed by Angst et al. (2005) to identify bipolarity in the general population, as well as patients with unipolar depression. The principal objective of this study was to assess the factor structure of the Korean version of the HCL-32 for mood disorder patients, via exploratory factor analysis (EFA) and confirmatory factor analysis (CFA). Methods The Korean version of HCL-32 were evaluated in a sample of 608 mood disorder patients, including 210 bipolar disorder patients and 398 unipolar disorder patients, all of whom were diagnosed in accordance with either the Structured Clinical Interview of DSM-IV or Mini International Neuropsychiatric Interview They were divided randomly into two groups, and then the EFA was administered to group 1 and the CFA was administered to group 2. Results A 3-factor structure for the HCL-32 was generated, which explained 44% of the total variance from EFA. Factor 1, comprising 18 items, was designated as 'elated mood/increased energy'; factor 2, comprising 8 items, was designated as 'risk-taking behavior/irritability'; and factor 3, comprising 2 items, was designated as 'increased sexual activity'. Researchers confirmed the 3-factor solution derived from group 1 by the CFA. Conclusion The primary findings of this study were the replication and confirmation of the 3-factor structure in Korean mood disorder patients; our results were consistent with previous EFAs. PMID:22216043

  12. Influence analysis for the factor analysis model with ranking data.

    PubMed

    Xu, Liang; Poon, Wai-Yin; Lee, Sik-Yum

    2008-05-01

    Influence analysis is an important component of data analysis, and the local influence approach has been widely applied to many statistical models to identify influential observations and assess minor model perturbations since the pioneering work of Cook (1986). The approach is often adopted to develop influence analysis procedures for factor analysis models with ranking data. However, as this well-known approach is based on the observed data likelihood, which involves multidimensional integrals, directly applying it to develop influence analysis procedures for the factor analysis models with ranking data is difficult. To address this difficulty, a Monte Carlo expectation and maximization algorithm (MCEM) is used to obtain the maximum-likelihood estimate of the model parameters, and measures for influence analysis on the basis of the conditional expectation of the complete data log likelihood at the E-step of the MCEM algorithm are then obtained. Very little additional computation is needed to compute the influence measures, because it is possible to make use of the by-products of the estimation procedure. Influence measures that are based on several typical perturbation schemes are discussed in detail, and the proposed method is illustrated with two real examples and an artificial example. PMID:18482479

  13. A Review of CEFA Software: Comprehensive Exploratory Factor Analysis Program

    ERIC Educational Resources Information Center

    Lee, Soon-Mook

    2010-01-01

    CEFA 3.02(Browne, Cudeck, Tateneni, & Mels, 2008) is a factor analysis computer program designed to perform exploratory factor analysis. It provides the main properties that are needed for exploratory factor analysis, namely a variety of factoring methods employing eight different discrepancy functions to be minimized to yield initial solutions, a…

  14. Uses of Factor Analysis in Counseling Psychology Research.

    ERIC Educational Resources Information Center

    Tinsley, Howard E. A.; Tinsley, Diane J.

    1987-01-01

    Explains factor analysis, discussing its relation to other multivariate techniques and describing characteristics of the data to consider in determining the appropriateness of factor analysis. Reviews considerations in making decisions about communality estimates, factor extraction, the number of factors to rotate, methods of factor rotation,…

  15. Designing Instructional Text in a Conversational Style: A Meta-Analysis

    ERIC Educational Resources Information Center

    Ginns, Paul; Martin, Andrew J.; Marsh, Herbert W.

    2013-01-01

    This article reviews research on the effects of conversational style on learning. Studies of conversational style have variously investigated "personalization" through changing instances of first-person address to second or third person, including sentences that directly address the learner; including more polite forms of address; and…

  16. Acoustic Analysis of Clear Versus Conversational Speech in Individuals with Parkinson Disease

    ERIC Educational Resources Information Center

    Goberman, A.M.; Elmer, L.W.

    2005-01-01

    A number of studies have been devoted to the examination of clear versus conversational speech in non-impaired speakers. The purpose of these previous studies has been primarily to help increase speech intelligibility for the benefit of hearing-impaired listeners. The goal of the present study was to examine differences between conversational and…

  17. Molecular gas in low-metallicity starburst galaxies:. Scaling relations and the CO-to-H2 conversion factor

    NASA Astrophysics Data System (ADS)

    Amorín, R.; Muñoz-Tuñón, C.; Aguerri, J. A. L.; Planesas, P.

    2016-04-01

    Context. Tracing the molecular gas-phase in low-mass star-forming galaxies becomes extremely challenging due to significant UV photo-dissociation of CO molecules in their low-dust, low-metallicity ISM environments. Aims: We aim to study the molecular content and the star-formation efficiency of a representative sample of 21 blue compact dwarf galaxies (BCDs), previously characterized on the basis of their spectrophotometric properties. Methods: We present CO (1-0) and (2-1) observations conducted at the IRAM-30m telescope. These data are further supplemented with additional CO measurements and multiwavelength ancillary data from the literature. We explore correlations between the derived CO luminosities and several galaxy-averaged properties. Results: We detect CO emission in seven out of ten BCDs observed. For two galaxies these are the first CO detections reported so far. We find the molecular content traced by CO to be correlated with the stellar and Hi masses, star formation rate (SFR) tracers, the projected size of the starburst, and its gas-phase metallicity. BCDs appear to be systematically offset from the Schmidt-Kennicutt (SK) law, showing lower average gas surface densities for a given ΣSFR, and therefore showing extremely low (≲0.1 Gyr) H2 and H2 +Hi depletion timescales. The departure from the SK law is smaller when considering H2 +Hi rather than H2 only, and is larger for BCDs with lower metallicity and higher specific SFR. Thus, the molecular fraction (ΣH2/ ΣHI) and CO depletion timescale (ΣH2/ ΣSFR) of BCDs is found to be strongly correlated with metallicity. Using this, and assuming that the empirical correlation found between the specific SFR and galaxy-averaged H2 depletion timescale of more metal-rich galaxies extends to lower masses, we derive a metallicity-dependent CO-to-H2 conversion factor αCO,Z ∝ (Z/Z⊙)- y, with y = 1.5(±0.3)in qualitative agreement with previous determinations, dust-based measurements, and recent model

  18. Analysis of the rationale for, and consequences of, nonprofit and for-profit ownership conversions.

    PubMed Central

    Mark, T L

    1999-01-01

    OBJECTIVES: To examine percursors to private hospitals conversion, both from nonprofit status to for-profit status and from for-profit to nonprofit status, as well as the effect of hospital conversions on hospital profitability, efficiency, staffing, and the probability of closure. DATA SOURCES: The Health Care Financing Administration's Medicare Cost Reports and the American Hospital Association's Annual Survey of Hospitals. STUDY DESIGN: Bivariate and multivariate analyses comparing conversion hospitals to nonconversion hospitals over time were conducted. DATA EXTRACTION METHODS: The study sample consisted of all private acute care hospital conversions that occurred from 1989 through 1992. PRINCIPAL FINDINGS: Hospitals that converted had significantly lower profit margins prior to converting than did nonconversion hospitals. This was particularly true for nonprofit to for-profit conversions. After converting, both nonprofit and for-profit hospitals significantly improved their profitability. Nonprofit to for-profit hospital conversions were associated with a decrease in the ratio of staff to patients. No association was found between for-profit to nonprofit conversion and staff-to-patient ratios. The difference seems partially attributed to the fact that nonprofit hospitals that converted had higher staff ratios than the industry average. For-profit to nonprofit hospital conversions were associated with an increase in the ratio of registered nurses to patients and administrators to patients, despite the fact that nonprofit and for-profit hospitals did not differ in these ratios. CONCLUSIONS: The improvement in financial performance following hospital conversions may be a benefit to the community that policymakers want to consider when regulating hospital conversions. PMID:10201853

  19. The CO-to-H2 Conversion Factor and Dust-to-gas Ratio on Kiloparsec Scales in Nearby Galaxies

    NASA Astrophysics Data System (ADS)

    Sandstrom, K. M.; Leroy, A. K.; Walter, F.; Bolatto, A. D.; Croxall, K. V.; Draine, B. T.; Wilson, C. D.; Wolfire, M.; Calzetti, D.; Kennicutt, R. C.; Aniano, G.; Donovan Meyer, J.; Usero, A.; Bigiel, F.; Brinks, E.; de Blok, W. J. G.; Crocker, A.; Dale, D.; Engelbracht, C. W.; Galametz, M.; Groves, B.; Hunt, L. K.; Koda, J.; Kreckel, K.; Linz, H.; Meidt, S.; Pellegrini, E.; Rix, H.-W.; Roussel, H.; Schinnerer, E.; Schruba, A.; Schuster, K.-F.; Skibba, R.; van der Laan, T.; Appleton, P.; Armus, L.; Brandl, B.; Gordon, K.; Hinz, J.; Krause, O.; Montiel, E.; Sauvage, M.; Schmiedeke, A.; Smith, J. D. T.; Vigroux, L.

    2013-11-01

    We present ~kiloparsec spatial resolution maps of the CO-to-H2 conversion factor (αCO) and dust-to-gas ratio (DGR) in 26 nearby, star-forming galaxies. We have simultaneously solved for αCO and the DGR by assuming that the DGR is approximately constant on kiloparsec scales. With this assumption, we can combine maps of dust mass surface density, CO-integrated intensity, and H I column density to solve for both αCO and the DGR with no assumptions about their value or dependence on metallicity or other parameters. Such a study has just become possible with the availability of high-resolution far-IR maps from the Herschel key program KINGFISH, 12CO J = (2-1) maps from the IRAM 30 m large program HERACLES, and H I 21 cm line maps from THINGS. We use a fixed ratio between the (2-1) and (1-0) lines to present our αCO results on the more typically used 12CO J = (1-0) scale and show using literature measurements that variations in the line ratio do not affect our results. In total, we derive 782 individual solutions for αCO and the DGR. On average, αCO = 3.1 M ⊙ pc-2 (K km s-1)-1 for our sample with a standard deviation of 0.3 dex. Within galaxies, we observe a generally flat profile of αCO as a function of galactocentric radius. However, most galaxies exhibit a lower αCO value in the central kiloparsec—a factor of ~2 below the galaxy mean, on average. In some cases, the central αCO value can be factors of 5-10 below the standard Milky Way (MW) value of αCO, MW = 4.4 M ⊙ pc-2 (K km s-1)-1. While for αCO we find only weak correlations with metallicity, the DGR is well-correlated with metallicity, with an approximately linear slope. Finally, we present several recommendations for choosing an appropriate αCO for studies of nearby galaxies.

  20. Vocal quality factors: analysis, synthesis, and perception.

    PubMed

    Childers, D G; Lee, C K

    1991-11-01

    The purpose of this study was to examine several factors of vocal quality that might be affected by changes in vocal fold vibratory patterns. Four voice types were examined: modal, vocal fry, falsetto, and breathy. Three categories of analysis techniques were developed to extract source-related features from speech and electroglottographic (EGG) signals. Four factors were found to be important for characterizing the glottal excitations for the four voice types: the glottal pulse width, the glottal pulse skewness, the abruptness of glottal closure, and the turbulent noise component. The significance of these factors for voice synthesis was studied and a new voice source model that accounted for certain physiological aspects of vocal fold motion was developed and tested using speech synthesis. Perceptual listening tests were conducted to evaluate the auditory effects of the source model parameters upon synthesized speech. The effects of the spectral slope of the source excitation, the shape of the glottal excitation pulse, and the characteristics of the turbulent noise source were considered. Applications for these research results include synthesis of natural sounding speech, synthesis and modeling of vocal disorders, and the development of speaker independent (or adaptive) speech recognition systems. PMID:1837797

  1. A stereoscopic video conversion scheme based on spatio-temporal analysis of MPEG videos

    NASA Astrophysics Data System (ADS)

    Lin, Guo-Shiang; Huang, Hsiang-Yun; Chen, Wei-Chih; Yeh, Cheng-Ying; Liu, Kai-Che; Lie, Wen-Nung

    2012-12-01

    In this article, an automatic stereoscopic video conversion scheme which accepts MPEG-encoded videos as input is proposed. Our scheme is depth-based, relying on spatio-temporal analysis of the decoded video data to yield depth perception cues, such as temporal motion and spatial contrast, which reflect the relative depths between the foreground and the background areas. Our scheme is shot-adaptive, demanding that shot change detection and shot classification be performed for tuning of algorithm or parameters that are used for depth cue combination. The above-mentioned depth estimation is initially block-based, followed by a locally adaptive joint trilateral upsampling algorithm to reduce the computing load significantly. A recursive temporal filter is used to reduce the possible depth fluctuations (and also artifacts in the synthesized images) resulting from wrong depth estimations. The traditional Depth-Image-Based-Rendering algorithm is used to synthesize the left- and right-view frames for 3D display. Subjective tests show that videos converted by our scheme provide comparable perceived depth and visual quality with those converted from the depth data calculated by stereo vision techniques. Also, our scheme is shown to outperform the well-known TriDef software in terms of human's perceived 3D depth. Based on the implementation by using "OpenMP" parallel programming model, our scheme is capable of executing in real-time on a multi-core CPU platform.

  2. Thermodynamic systems analysis of open-cycle Ocean Thermal Energy Conversion (OTEC)

    NASA Astrophysics Data System (ADS)

    Parsons, B. K.; Bharathan, D.; Althof, J. A.

    1985-09-01

    This report describes an updated thermal-hydraulic systems analysis program called OTECSYS that studies the integrated performance of an open-cycle ocean thermal energy conversion (OTEC) plant, specifically, the effects of component performance, design parameters, and site specific resource data on the total system performance and plant size. OTECSYS can size the various open-cycle power cycle and hydraulic components. Models for the evaporator, mist eliminator, turbine-generator diffuser, direct-contact condenser, exhaust compressors, seawater pumps, and seawater piping are included, as are evaluations of the pressure drops associated with the intercomponent connections. It can also determine the required steam, cold seawater, and warm seawater flow rates. OTECSYS uses an approach similar to earlier work and integrates the most up-to-date developments in component performance and configuration. The program format allows the user to examine subsystem concepts not currently included by creating new component models. It will be useful to the OTEC plant designer who wants to quantify the design point sizing, performance, and power production using site-specific resource data. Detailed design trade-offs are easily evaluated, and several examples of these types of investigations are presented using plant size and power as criteria.

  3. Factorized molecular wave functions: Analysis of the nuclear factor

    SciTech Connect

    Lefebvre, R.

    2015-06-07

    The exact factorization of molecular wave functions leads to nuclear factors which should be nodeless functions. We reconsider the case of vibrational perturbations in a diatomic species, a situation usually treated by combining Born-Oppenheimer products. It was shown [R. Lefebvre, J. Chem. Phys. 142, 074106 (2015)] that it is possible to derive, from the solutions of coupled equations, the form of the factorized function. By increasing artificially the interstate coupling in the usual approach, the adiabatic regime can be reached, whereby the wave function can be reduced to a single product. The nuclear factor of this product is determined by the lowest of the two potentials obtained by diagonalization of the potential matrix. By comparison with the nuclear wave function of the factorized scheme, it is shown that by a simple rectification, an agreement is obtained between the modified nodeless function and that of the adiabatic scheme.

  4. Nonrhabdomyosarcomatous abdominopelvic sarcomas: Analysis of prognostic factors

    PubMed Central

    Iqbal, Nida; Shukla, Nootan K.; Deo, S. V. S.; Agarwala, Sandeep; Sharma, D. N.; Sharma, Meher C.; Bakhshi, Sameer

    2016-01-01

    Background: Data concerning treatment outcome and prognostic factors in sarcomas of abdomen and pelvis are sparse in literature. Methods and Results: Of 696 patients with nonrhabdomyosarcomatous soft tissue sarcoma registered at our center between June 2003 and December 2012, 112 (16%) patients of sarcomas arising from abdomen and pelvis were identified, of which 88 patients were analyzed for treatment outcome and prognostic factors. The median age was 40 years (range: 1–78 years) with a male: female ratio of 0.7:1. Twenty-one (24%) patients were metastatic at baseline. The most common tumor sites were retroperitoneum in 70% patients and abdominal wall in 18% patients. Leiomyosarcoma was the most common histological subtype in 36% patients followed by liposarcoma in 17% patients. Thirty-five (40%) patients had Grade III tumors. Forty-six (52%) patients underwent surgical resection. At a median follow-up of 43 months (range: 2–94 months), the 5-year event-free survival (EFS) and overall survival (OS) were 35% and 42%, with a median of 22 months and 43 months, respectively. Multivariate analysis identified male gender (P - 0.03, hazard ratio [HR] - 0.46, 95% confidence interval [CI] - 0.23–0.92), baseline metastatic disease (P - 0.01, HR - 2.98, 95% CI - 1.27–6.98) and Grade III tumors (P - 0.02, HR - 1.84, 95% CI - 1.08–3.13) as factors associated with poor EFS, whereas baseline metastatic disease (P < 0.001, HR - 5.45, 95% CI - 2.31–12.87) and unresectability (P - 0.01, HR - 2.72, 95% CI - 1.27–5.83) were associated with poor OS. Conclusion: This is a single-institutional study of patients with abdominopelvic sarcomas where gender was identified as a new factor affecting survival apart from baseline presentation, histologic grade, and surgical resection. PMID:27168708

  5. Characterization of selected Ohio coals to predict their conversion behavior relative to 104 North American Coals. [Factors correlating with liquefaction behavior

    SciTech Connect

    Whitacre, T. P.; Hunt, T. J.; Kneller, W. A.

    1982-02-01

    Twenty-six coal samples from Ohio were collected as washed and seam samples, and lithobodies within the seams. Characterization of these samples included determination of % maceral, % anti R/sub max/, LTA, chlorine content and proximate/ultimate and qualitative mineral analyses. These data were compared to data from a similar project by Yarzab, R.F., et al., 1980 completed at Pennsylvania State University using tetralin as the hydrogen donor solvent. The characteristics of these coals were correlated with liquefaction conversion and other data accrued on 104 North American coals by statistical analyses. Utilizing percent carbon, sulfur, volatile matter, reflectance, vitrinite and total reactive macerals, Q-mode cluster analysis demonstrated that Ohio coals are more similar to the coals of the Interior province than to those of the Appalachian province. Linear multiple regression analysis for the 104 North American coals provided a prediction equation for conversion (R = .96). The predicted conversion values for the samples range from 58.8 to 79.6%, with the Lower Kittanning (No. 5) and the Middle Kittanning (No. 6) coal seams showing the highest predicted percent conversion (respectively, 73.4 and 72.2%). The moderately low FSI values for the No. 5 and No. 6 coals (respectively, 2.5 and 3) and their moderately high alkaline earth content (respectively, 0.69 and 0.74%) suggest that these coals possess the best overall properties for conversion. Stepwise regression has indicated that the most important coal characteristics affecting conversion are, in decreasing order of importance: % volatile matter, % vitrinite and % total sulfur. Conversion processes can be expected to produce higher yields with Ohio coals due to the presence of such mineral catalysts as pyrite and kaolinite. It is believed that the presence of these disposable catalysts increases the marketability of Ohio coals.

  6. On the field-to-current conversion factors for large bipolar lightning discharge events in winter thunderstorms in Japan

    NASA Astrophysics Data System (ADS)

    Chen, Long; Zhang, Qilin; Hou, Wenhao; Tao, Yulang

    2015-07-01

    In this paper we have simulated the far-field waveform characteristic of large bipolar events (LBEs) occurred in winter thunderstorms in Japan and compared the field-to-current conversion factors (FCCFs) of LBEs with that of the lightning cloud-to-ground (CG) return stroke (RS) in summer thunderstorm. As for the physical process of LBEs, Wu et al. (2014) considered that LBEs may be very similar to the typical lightning RS (RS-like process) or caused by an initial continuous current pulse (ICC-like process) in upward lightning flashes. We assume that the lightning channel length of LBEs ranges from 500 m to 1000 m, and the height of tall object struck by LBEs is from 100 m to 300 m. By using the bouncing wave model, we found that only when the injected current waveform of LBEs is characterized with a symmetric Gaussian pulse, the simulated far-field waveform of LBEs both for RS-like process and ICC-like process is similar to that observed by Wu et al. (2014). For striking tall objects with heights from 100 m and 300 m, the FCCFs of LBEs are positively correlated with its channel length and derivatives of injected current waveform, and the FCCF for RS-like process is about similar to that for ICC-like process. However, the FCCFs of LBEs are very different from lightning RS in summer thunderstorm; that is to say, the FCCFs developed for the well-known lightning RS in summer thunderstorm are not suitable for LBEs.

  7. Budget impact analysis of conversion from cyclosporine to sirolimus as immunosuppressive medication in renal transplantation therapy

    PubMed Central

    Foroutan, Naghmeh; Rasekh, Hamid R; Salamzadeh, Jamshid; Jamshidi, Hamid R; Nafar, Mohsen

    2013-01-01

    Objectives The aim of this study was to determine budget impact of conversion from cyclosporine (CsA) to sirolimus (SRL) in renal transplant therapy (RTT) from the perspective of insurance organizations in Iran. Methods An Excel-based model was developed to determine cost of RTT, comparing current CsA based therapy to an mTOR inhibitor-based therapy regimen. Total cost included both cost of immunosuppressive agents and relative adverse events. The inputs were derived from database of Ministry of Health and insurance organizations, hospital and pharmacy based registries, and available literature that were varied through a one-way sensitivity analysis. According to the model, there were almost 17,000 patients receiving RTT in Iran, out of which about 2,200 patients underwent the operation within the study year. The model was constructed based on the results of a local RCT, in which test and control groups received CsA, SRL, and steroids over the first 3 months posttransplantation and, from the fourth month on, CsA, mycophenolate mofetil (MMF), and steroids were used in the CsA group and SRL, MMF, and steroids were administered in the SRL group, respectively. Results The estimated cost of RTT with CsA was US$4,850,000 versus US$4,300,000 receiving SRL. These costs corresponded to the cost saving of almost US$550,000 for the payers. Conclusion To evaluate the financial consequence of adding mTOR inhibitors to the insurers’ formulary, in the present study, a budget impact analysis was conducted on sirolimus. Fewer cases of costly adverse events along with lower required doses of MMF related to SRL based therapies were major reasons for this saving budgetary impact. PMID:24159260

  8. Influence of light-activation protocol on methacrylate resin-composite evaluated by dynamic mechanical analysis and degree of conversion.

    PubMed

    Giorgi, Maria Cecília C; Pistor, Vinícius; Mauler, Raquel S; Lima, Débora A N L; Marchi, Giselle M; Aguiar, Flávio H B

    2015-05-01

    The aim of this study was to evaluate the degree of conversion (DC) and to identify the viscoelastic properties: storage modulus (E'), loss modulus (E"), tangent delta (tan δ), and glass transition temperature (T g ) of a microhybrid resin-composite light-activated by three different protocols. A Filtek Z250 (3 M ESPE) shade A3 was inserted in a Teflon mold (21 mm × 5 mm × 1 mm for viscoelastic properties; and 5 mm × 1 mm for DC) and light-activated according to the following light-activation protocols: (S) 1,000 mW/cm(2) × 19 s, (HP) 1,400 mW/cm(2) × 14 s, and (PE) 3,200 mW/cm(2) × 6 s, all set up to deliver 19 J/cm(2). Viscoelastic properties was assessed by dynamic mechanical analysis (DMA) (n = 3), performed in single cantilever clamped mode. DC (n = 5) was measured by FTIR on top (T) and bottom (B) surfaces, and the data was submitted to a split-plot one-way ANOVA. For DC, there was a significant effect for surface factor and light-activation protocols factor. Top surface showed higher DC than B in all experimental conditions. Light-activation protocols S and HP resulted in higher DC than PE and were similar between them. Viscoelastic properties (E', E", tan δ, T g ) were not affected by light-activation protocols. It could be concluded that light-activation protocols influenced DC but not influenced the viscoelastic properties. PMID:24740520

  9. Adenovirus-mediated expression of myogenic differentiation factor 1 (MyoD) in equine and human dermal fibroblasts enables their conversion to caffeine-sensitive myotubes.

    PubMed

    Fernandez-Fuente, Marta; Martin-Duque, Pilar; Vassaux, Georges; Brown, Susan C; Muntoni, Francesco; Terracciano, Cesare M; Piercy, Richard J

    2014-03-01

    Several human and animal myopathies, such as malignant hyperthermia (MH), central core disease and equine recurrent exertional rhabdomyolysis (RER) are confirmed or thought to be associated with dysfunction of skeletal muscle calcium regulation. For some patients in whom the genetic cause is unknown, or when mutational analysis reveals genetic variants with unclear pathogenicity, defects are further studied through use of muscle histopathology and in vitro contraction tests, the latter in particular, when assessing responses to ryanodine receptor agonists, such as caffeine. However, since muscle biopsy is not always suitable, researchers have used cultured cells to model these diseases, by examining calcium regulation in myotubes derived from skin, following forced expression of muscle-specific transcription factors. Here we describe a novel adenoviral vector that we used to express equine MyoD in dermal fibroblasts. In permissive conditions, transduced equine and human fibroblasts differentiated into multinucleated myotubes. We demonstrate that these cells have a functional excitation-calcium release mechanism and, similarly to primary muscle-derived myotubes, respond in a dose-dependent manner to increasing concentrations of caffeine. MyoD-induced conversion of equine skin-derived fibroblasts offers an attractive method for evaluating calcium homeostasis defects in vitro without the need for invasive muscle biopsy. PMID:24342283

  10. Another look at retroactive and proactive interference: a quantitative analysis of conversion processes.

    PubMed

    Blank, Hartmut

    2005-02-01

    Traditionally, the causes of interference phenomena were sought in "real" or "hard" memory processes such as unlearning, response competition, or inhibition, which serve to reduce the accessibility of target items. I propose an alternative approach which does not deny the influence of such processes but highlights a second, equally important, source of interference-the conversion (Tulving, 1983) of accessible memory information into memory performance. Conversion is conceived as a problem-solving-like activity in which the rememberer tries to find solutions to a memory task. Conversion-based interference effects are traced to different conversion processes in the experimental and control conditions of interference designs. I present a simple theoretical model that quantitatively predicts the resulting amount of interference. In two paired-associate learning experiments using two different types of memory tests, these predictions were corroborated. Relations of the present approach to traditional accounts of interference phenomena and implications for eyewitness testimony are discussed. PMID:15847231

  11. Conversations between carers and people with schizophrenia: a qualitative analysis using leximancer.

    PubMed

    Cretchley, Julia; Gallois, Cindy; Chenery, Helen; Smith, Andrew

    2010-12-01

    We examined conversations between people with schizophrenia (PwS) and family or professional carers with whom they interacted frequently. We allocated PwS to one of two communication profiles: Low-activity communicators talked much less than their conversational partners, whereas high-activity communicators talked much more. We used Leximancer text analytics software to analyze the conversations. We found that carers used different strategies to accommodate to the PwS's behavior, depending on the PwS's communication profile and their relationship. These findings indicate that optimal communication strategies depend on the PwS's conversational tendencies and the relationship context. They also suggest new opportunities for qualitative assessment via intelligent text analytics technologies. PMID:20675536

  12. Speaker Perceptions of Communicative Effectiveness: Conversational Analysis of Student-Teacher Talk

    ERIC Educational Resources Information Center

    Behrens, Susan; Jablon, Ann

    2008-01-01

    This study examines verbal behavior in student-teacher talk and alignment of perceptions of communication effectiveness. Heightened awareness of conversational patterns is more productive in the learning environment than the rote use of discourse markers.

  13. Development and Analysis of Advanced High-Temperature Technology for Nuclear Heat Transport and Power Conversion

    SciTech Connect

    Per F. Peterson

    2010-03-01

    This project by the Thermal Hydraulics Research Laboratory at U.C. Berkeley Studied advanced high-temperature heat transport and power conversion technology, in support of the Nuclear Hydrogen Initiative and Generation IV.

  14. A Monte Carlo Study of Recovery of Weak Factor Loadings in Confirmatory Factor Analysis

    ERIC Educational Resources Information Center

    Ximenez, Carmen

    2006-01-01

    The recovery of weak factors has been extensively studied in the context of exploratory factor analysis. This article presents the results of a Monte Carlo simulation study of recovery of weak factor loadings in confirmatory factor analysis under conditions of estimation method (maximum likelihood vs. unweighted least squares), sample size,…

  15. Practical Considerations for Using Exploratory Factor Analysis in Educational Research

    ERIC Educational Resources Information Center

    Beavers, Amy S.; Lounsbury, John W.; Richards, Jennifer K.; Huck, Schuyler W.; Skolits, Gary J.; Esquivel, Shelley L.

    2013-01-01

    The uses and methodology of factor analysis are widely debated and discussed, especially the issues of rotational use, methods of confirmatory factor analysis, and adequate sample size. The variety of perspectives and often conflicting opinions can lead to confusion among researchers about best practices for using factor analysis. The focus of the…

  16. Rhythm and Blues - Amalie's 152nd session: From psychoanalysis to conversation and metaphor analysis - and back again.

    PubMed

    Buchholtz, Michael B; Spiekermann, Jane; Kächele, Horst

    2015-06-01

    Conversation analysis and psychotherapy process research is an evolving field promising new insights for therapeutic practice. As the specimen case of Amalie, especially her 152nd session, has been investigated using various methods - of which we give a short overview - we offer a new analysis of session 152 based on a new transcription which allows for more detailed listening to the prosodic properties of this analytic dyad. Our findings show a) how analyst and patient co-create their common conversational object called psychoanalysis; b) how a lot of up-to-now not described analytical tools are applied, that can be described as "practices"; c) how a "dance of insight" is enacted by both participants in a common creation making patterns of interaction visible from "both sides"; d) how participants create metaphors as conversational and cognitive tools to reduce the enormous complexity of the analytic exchange and for other purposes; e) that prosodic rhythmicity and other prosodic features are best integrated in a threefold model for analytic conversation consisting of "interaction engine", "talking to" and "talking about" the patient. The study is presented as hypothesis-generating research based on verbal, not statistical data. PMID:26173891

  17. [Evaluation and examination of accuracy for the conversion factors of effective dose per dose-length product].

    PubMed

    Kobayashi, Masanao; Ootsuka, Tomoko; Suzuki, Syoichi

    2013-01-01

    The purpose of this paper is to reappraise the accuracy of a conversion coefficient (k) reported by International Commission on Radiological Protection Publication 102 Table A.2. The effective doses of the routine head computed tomography (CT), the routine chest CT, the perfusion CT, and the coronary CT were evaluated using the conversion coefficient (adult head: 0.021 mSv·mGy⁻¹·cm⁻¹, adult chest: 0.014 mSv·mGy⁻¹·cm⁻¹). The dose length product (DLP) used the value displayed on the console on each scanning condition. The effective doses were evaluated using a human body type phantom (Alderson Rando phantom) and thermoluminescent dosimeter (TLD) elements for comparison with the converted value. This paper reported that the effective doses evaluated from conversion coefficient became different by 0.3 mSv (17%) compared with measurements, the effective dose computed with the conversion coefficient of the adult chest may be underestimated by 45%, and the bolus-tracking which scans the narrow beams should not use a conversion coefficient. PMID:23358334

  18. Anatomical and morphogenetic analysis of seismoelectric conversion patterns at geological units

    NASA Astrophysics Data System (ADS)

    Kröger, B.; Kemna, A.

    2012-04-01

    Characterisation of the hydraulic properties of a reservoir, such as porosity and permeability, and their spatial distribution plays an important role in many subsurface geophysical investigations. A fully developed seismoelectric exploration method is very appealing since it would offer the potential to directly determine these parameters in field-scale applications. In fluid-saturated rocks, seismic waves can generate electromagnetic fields, due to electrokinetic coupling mechanisms at the fluid-mineral interface. Using numerical modelling, we investigated the spatio-temporal occurrence and evolution of the seismoelectric effects that occur in spatially confined lithological units. Such geometries may represent clay lenses embedded in an aquifer or petroleum deposits in a host rock. For the modelling, we use a simplified time-domain formulation of the coupled physical problem and its efficient implementation in a 2D finite-element framework. Two occurring seismoelectric phenomena are investigated: (1) the co-seismic field associated with the seismic displacement at each point and (2) the interface response generated at layer boundaries. To gain insight into the morphogenetic field behaviour of the seismoelectric effects, we run numerical simulations using several material parameter set-ups for various target geometries. Accordingly, we varied both the thickness of the confined units and the value of the electrical bulk conductivity in the considered media. The analysis of the seismoelectric effects revealed an important difference in the generation of the interface response at either electrically conductive or resistive units. We find that the contrast in the electrical bulk conductivity between the host rock and the target geological unit controls the shape and structure of the seismoelectric conversion patterns. Our results show that the seismoelectric interface response captures both the petrophysical and geometrical characteristics of the converting

  19. Likelihood-Based Confidence Intervals in Exploratory Factor Analysis

    ERIC Educational Resources Information Center

    Oort, Frans J.

    2011-01-01

    In exploratory or unrestricted factor analysis, all factor loadings are free to be estimated. In oblique solutions, the correlations between common factors are free to be estimated as well. The purpose of this article is to show how likelihood-based confidence intervals can be obtained for rotated factor loadings and factor correlations, by…

  20. Conversion and correction factors for historical measurements of iodine-131 in Hanford-area vegetation 1948--1951. Hanford Environmental Dose Reconstruction Project

    SciTech Connect

    Denham, D.H.; Mart, E.I.; Thiede, M.E.

    1993-09-01

    This report is a part of the Hanford Environmental Dose Reconstruction (HEDR) Project, whose goal is to estimate the radiation dose that individuals could have received from emissions since 1944 at the US Department of Energy`s (DOE) Hanford Site near Richland, Washington. The key radionuclide emitted that would affect the radiation dose was iodine-131 (Napier 1992). Because the early methods of measuring iodine-131 were not comparable to later techniques, conversion and correction factors are needed to convert the historical measurement data into concentration values that would be determined using today`s knowledge and technologies. This report describes the conversion and correction factors developed for reconstructing historical measurements of iodine-131 in Hanford-area vegetation, which was collected from 1948 through the end of December 1951.

  1. The role of psychiatrists in diagnosing conversion disorder: a mixed-methods analysis

    PubMed Central

    Kanaan, Richard A; Armstrong, David; Wessely, Simon

    2016-01-01

    Objective Since DSM-5 removed the requirement for a psychosocial formulation, neurologists have been able to make the diagnosis of conversion disorder without psychiatric input. We sought to examine whether neurologists and specialist psychiatrists concurred with this approach. Design We used mixed methods, first surveying all the neurologists in the UK and then interviewing the neuropsychiatrists in a large UK region on the role of psychiatrists in diagnosing conversion disorder. Results Of the surveyed neurologists, 76% did not think that psychiatrists were essential for the diagnosis and 71% thought that psychiatrists did not even consider conversion disorder when referred a case. The neuropsychiatrists who were interviewed held complex models of conversion disorder. They believed all cases could be explained psychosocially in theory, but the nature of the diagnostic encounter often prevented it in practice; all felt that psychosocial formulation could be very helpful and some felt that it was essential to diagnosis. Conclusion Although neurologists do not think psychiatrists are required for diagnosing conversion disorder, specialist psychiatrists disagree, at least in some cases. PMID:27274253

  2. Conversion and correction factors for historical measurements of Iodine-131 in Hanford-area vegetation, 1945--1947: Draft. Hanford Environmental Dose Reconstruction Project

    SciTech Connect

    Mart, E.I.; Denham, D.H.; Thiede, M.E.

    1993-05-01

    This report is a result of the Hanford Environmental Dose Reconstruction (HEDR) Project whose goal is to estimate the radiation dose that individuals could have received from emissions since 1944 at the US Department of Energy`s (DOE) Hanford Site near Richland, Washington. The report describes in detail the reconstructed conversion and correction factors for historical measurements of iodine-131 in Hanford-area vegetation which was collected from the beginning of October 1945 through the end of December 1947.

  3. Review of second law analysis techniques applicable to the Energy Conversion and Utilization Technologies Thermal Sciences Program

    SciTech Connect

    Drost, M.K.; Zaworski, J.R.

    1989-06-01

    This report describes a review of second law analysis emphasizing techniques applicable to basic research in the thermal sciences. Second law analysis is a class of thermodynamic analysis techniques that has become increasingly popular in the design of thermal systems. Pacific Northwest Laboratory conducted this review in l987 for the US Department of Energy's (DOE) Energy Conversion and Utilization Technologies (ECUT) Program. The primary goal is to determine whether second law techniques can be used in guiding or contributing to basic research in the thermal sciences. 35 refs.

  4. Mabolizable energy differences between values calculated using energy conversion factors and actual values determined by metabolic study of Korean starch foods.

    PubMed

    Kim, Eunmi; Choi, Jinho; Kim, Hyejin

    2014-04-01

    This study was conducted to compare the metabolizable energies of Korean starch foods by an animal metabolic study with those calculated using well-known energy conversion factors. There were 12 experimental diets (that is, 7 Korean foods, 3 Western foods, and 2 control foods): barley, brown rice, laver-rolled rice, rice mixed with vegetables and meat, seafood noodle soup, rice cake soup, rice cake in hot pepper paste, pizza, hamburger, spaghetti, basal diet, and glucose. Each diet comprised 70% basal diet and 30% experimental food. After 3 d of adaptation, a metabolic trial was performed for 4 d. The apparent metabolizable energy of pizza, hamburger, spaghetti, and rice cake soup were significantly higher than that of the basal diet group (P < 0.05). For barley, brown rice, laver-rolled rice, rice mixed with vegetables and meat, and seafood noodle soup, the differences between the actual and calculated energies were 8.7%, 13.3%, 4.5%, 17.2%, and 4.1%, respectively, and the actual energy contents were lower than those calculated using the Atwater conversion factor. The results of this study show that the energy contents of Korean foods are significantly different from those calculated using the conversion factors based on the food composition. Therefore, because Korean starch foods are considered to be calorie-rich based on calculations, their energy contents can be accurately determined only by animal experiments. PMID:24621178

  5. Multiple factor analysis with continuous and dichotomous variables

    NASA Astrophysics Data System (ADS)

    Thanoon, Thanoon Y.; Adnan, Robiah; Saffari, Seyed Ehsan

    2014-12-01

    In this paper, continuous and dichotomous variables are used in multiple factor analysis method. When all variables within the same group are continuous, we use principal component analysis method in factor analysis, if all variables within the same group are dichotomous we use multiple correspondence analysis method in factor analysis. Statistical analyses, which involve Eigen roots, Eigen vectors, multiple factor loadings, correlation coefficient RV, contribution table, are discussed. The proposed procedure is illustrated by a lung cancer data consists of four groups "group of personal variables", "group of therapeutic variables", "group of nutritional variables", "group of genetic variables". Analysis are done by using XLSTAT program.

  6. Solar energy conversion systems engineering and economic analysis radiative energy input/thermal electric output computation. Volume III

    SciTech Connect

    Russo, G.

    1982-09-01

    The direct energy flux analytical model, an analysis of the results, and a brief description of a non-steady state model of a thermal solar energy conversion system implemented on a code, SIRR2, as well as the coupling of CIRR2 which computes global solar flux on a collector and SIRR2 are presented. It is shown how the CIRR2 and, mainly, the SIRR2 codes may be used for a proper design of a solar collector system. (LEW)

  7. Alternative Factor Models and Factorial Invariance of the GHQ-12: A Large Sample Analysis Using Confirmatory Factor Analysis

    ERIC Educational Resources Information Center

    Shevlin, Mark; Adamson, Gary

    2005-01-01

    This study tested alternative factor models of the General Health Questionnaire-12 (GHQ-12), based on previous research findings, with a large sample using confirmatory factor analysis. An alternative models framework was used to test 6 factor analytic models. A 3-factor model was the best explanation of the sample data. The 3 factors were labeled…

  8. FABIA: factor analysis for bicluster acquisition

    PubMed Central

    Hochreiter, Sepp; Bodenhofer, Ulrich; Heusel, Martin; Mayr, Andreas; Mitterecker, Andreas; Kasim, Adetayo; Khamiakova, Tatsiana; Van Sanden, Suzy; Lin, Dan; Talloen, Willem; Bijnens, Luc; Göhlmann, Hinrich W. H.; Shkedy, Ziv; Clevert, Djork-Arné

    2010-01-01

    Motivation: Biclustering of transcriptomic data groups genes and samples simultaneously. It is emerging as a standard tool for extracting knowledge from gene expression measurements. We propose a novel generative approach for biclustering called ‘FABIA: Factor Analysis for Bicluster Acquisition’. FABIA is based on a multiplicative model, which accounts for linear dependencies between gene expression and conditions, and also captures heavy-tailed distributions as observed in real-world transcriptomic data. The generative framework allows to utilize well-founded model selection methods and to apply Bayesian techniques. Results: On 100 simulated datasets with known true, artificially implanted biclusters, FABIA clearly outperformed all 11 competitors. On these datasets, FABIA was able to separate spurious biclusters from true biclusters by ranking biclusters according to their information content. FABIA was tested on three microarray datasets with known subclusters, where it was two times the best and once the second best method among the compared biclustering approaches. Availability: FABIA is available as an R package on Bioconductor (http://www.bioconductor.org). All datasets, results and software are available at http://www.bioinf.jku.at/software/fabia/fabia.html Contact: hochreit@bioinf.jku.at Supplementary information: Supplementary data are available at Bioinformatics online. PMID:20418340

  9. Preliminary draft industrial siting administration permit application: Socioeconomic factors technical report. Final technical report, November 1980-May 1982. [Proposed WyCoalGas project in Converse County, Wyoming

    SciTech Connect

    Not Available

    1982-01-01

    Under the with-project scenario, WyCoalGas is projected to make a difference in the long-range future of Converse County. Because of the size of the proposed construction and operations work forces, the projected changes in employment, income, labor force, and population will alter Converse County's economic role in the region. Specifically, as growth occurs, Converse County will begin to satisfy a larger portion of its own higher-ordered demands, those that are currently being satisfied by the economy of Casper. Business-serving and household-serving activities, currently absent, will find the larger income and population base forecast to occur with the WyCoalGas project desirable. Converse County's economy will begin to mature, moving away from strict dependence on extractive industries to a more sophisticated structure that could eventually appeal to national, and certainly, regional markets. The technical demand of the WyCoalGas plant will mean a significant influx of varying occupations and skills. The creation of basic manufacturing, advanced trade and service sectors, and concomitant finance and transportation firms will make Converse County more economically autonomous. The county will also begin to serve market center functions for the smaller counties of eastern Wyoming that currently rely on Casper, Cheyenne or other distant market centers. The projected conditions expected to exist in the absence of the WyCoalGas project, the socioeconomic conditions that would accompany the project, and the differences between the two scenarios are considered. The analysis is keyed to the linkages between Converse County and Natrona County.

  10. Erikson Psychosocial Stage Inventory: A Factor Analysis

    ERIC Educational Resources Information Center

    Gray, Mary McPhail; And Others

    1986-01-01

    The 72-item Erikson Psychosocial Stage Inventory (EPSI) was factor analyzed for a group of 534 university freshmen and sophomore students. Seven factors emerged, which were labeled Initiative, Industry, Identity, Friendship, Dating, Goal Clarity, and Self-Confidence. Item's representing Erikson's factors, Trust and Autonomy, were dispersed across…

  11. Social Facilitation Effects by Pedagogical Conversational Agent: Lexical Network Analysis in an Online Explanation Task

    ERIC Educational Resources Information Center

    Hayashi, Yugo

    2015-01-01

    The present study investigates web-based learning activities of undergraduate students who generate explanations about a key concept taught in a large-scale classroom. The present study used an online system with Pedagogical Conversational Agent (PCA), asked to explain about the key concept from different points and provided suggestions and…

  12. Analysis of effect of electrolyte types on electrokinetic energy conversion in nanoscale capillaries.

    PubMed

    Chein, Reiyu; Tsai, Kunyong; Yeh, Liying

    2010-01-01

    An analytical study on the effect of electrolyte types on the electrokinetic energy conversion is presented using nanoscale cylindrical capillary, which is either positively or negatively charged. The sign of surface charge determines the role and concentration magnitude of ions in the capillary and the energy conversion performance. Our study shows that the electrokinetic energy conversion performance (maximum efficiency, pressure rise and streaming potential) are approximately identical for 1:1 (KCl), 2:1 (CaCl2) and 3:1 (LaCl3) electrolytes when capillary is positively charged. For negatively charged capillary, energy conversion performance degrades significantly with the increase of counter-ion valence. For both positively and negatively charged capillaries, higher maximum efficiency can be resulted in low bulk concentration and surface charge density regimes. However, high maximum pressure rise generation for the pumping is found in the low bulk concentration and high surface charge density regimes. For the electric power generation, higher maximum streaming potential is found when both bulk concentration and surface charge density are low. PMID:20119963

  13. Evidence of Mentor Learning and Development: An Analysis of New Zealand Mentor/Mentee Professional Conversations

    ERIC Educational Resources Information Center

    Langdon, Frances J.

    2014-01-01

    While studies have shown that mentoring is essential to the development of new teachers, fewer investigations have examined what mentors learn about themselves and about mentoring through this role. In this study, the conversations between 13 mentors and their mentees were analysed, along with mentor self-evaluations and focus group data, over two…

  14. DIGITAL IMAGE ANALYSIS REPORTS: THE CONVERSION OF EPIC'S TRADITIONAL SITE CHARACTERIZATION PRODUCT

    EPA Science Inventory

    Over the past several years EPIC has been exploring the practicality and cost-effectiveness of providing its traditional hard-copy report product in digital form. This conversion has a number of practical uses including- 1) compatibility for use as data layers in a GIS; 2) transp...

  15. Teaching and Learning English in Thailand and the Integration of Conversation Analysis (CA) into the Classroom

    ERIC Educational Resources Information Center

    Teng, Bunthan; Sinwongsuwat, Kemtong

    2015-01-01

    This paper provides an overview of English language teaching and learning, specifically as it pertains to teaching English conversational skills in Thailand. The paper examines the shortcomings of the Communicative Language Teaching (CLT) approach, the current dominant pedagogical approach in the nation, and explores how the integration of…

  16. Simulation Analysis on Photoelectric Conversion Characteristics of Silicon Nanowire Array Photoelectrodes.

    PubMed

    Zhao, Yong; Yu, Jin; Fang, Li-Guang; Zheng, Jun; Wang, Hui-Qin; Yuan, Ji-Ren; Wu, Shaolong; Cheng, Guo-An

    2015-12-01

    Semiconductor nanowire photoelectrochemical cells have attracted extensive attention in the light-conversion field owing to the low-cost preparation, excellent optical absorption, and short distance of carrier collection. Although there are numbers of experimental investigations to improve the device performance, the understanding of the detailed process of photoelectric conversion needs to be further improved. In this work, a thorough optoelectronic simulation is employed to figure out how the nanowire diameter, doping concentration, and illumination wavelength affect the photoelectric conversion characteristics of the silicon nanowire array photoelectrodes. We find that two balances should be carefully weighted between optical absorption and photogenerated-carrier collection, along with between short-circuit photocurrent density and open-circuit voltage. For the small-diameter nanowire array photoelectrodes, the overall absorption is higher than that of the larger-diameter ones with the most contribution from the nanowires. However, the substrate shows increasing absorption with increasing illumination wavelength. Higher doping density leads to a larger open-circuit voltage; while lower doping density can guarantee a relatively higher short-circuit photocurrent. To obtain high-light-conversion-efficiency photoelectrodes, the doping density should be carefully chosen with considerations of illumination wavelength and surface recombination. Suppressing the surface recombination velocity can effectively enhance the short-circuit photocurrent (open-circuit voltage) for the lightly (heavily) doped nanowire array photoelectrodes. Our systematical results provide a theoretical guidance for the photoelectrochemical devices based on semiconductor nanostructures. PMID:26123274

  17. Simulation Analysis on Photoelectric Conversion Characteristics of Silicon Nanowire Array Photoelectrodes

    NASA Astrophysics Data System (ADS)

    Zhao, Yong; Yu, Jin; Fang, Li-Guang; Zheng, Jun; Wang, Hui-Qin; Yuan, Ji-Ren; Wu, Shaolong; Cheng, Guo-An

    2015-06-01

    Semiconductor nanowire photoelectrochemical cells have attracted extensive attention in the light-conversion field owing to the low-cost preparation, excellent optical absorption, and short distance of carrier collection. Although there are numbers of experimental investigations to improve the device performance, the understanding of the detailed process of photoelectric conversion needs to be further improved. In this work, a thorough optoelectronic simulation is employed to figure out how the nanowire diameter, doping concentration, and illumination wavelength affect the photoelectric conversion characteristics of the silicon nanowire array photoelectrodes. We find that two balances should be carefully weighted between optical absorption and photogenerated-carrier collection, along with between short-circuit photocurrent density and open-circuit voltage. For the small-diameter nanowire array photoelectrodes, the overall absorption is higher than that of the larger-diameter ones with the most contribution from the nanowires. However, the substrate shows increasing absorption with increasing illumination wavelength. Higher doping density leads to a larger open-circuit voltage; while lower doping density can guarantee a relatively higher short-circuit photocurrent. To obtain high-light-conversion-efficiency photoelectrodes, the doping density should be carefully chosen with considerations of illumination wavelength and surface recombination. Suppressing the surface recombination velocity can effectively enhance the short-circuit photocurrent (open-circuit voltage) for the lightly (heavily) doped nanowire array photoelectrodes. Our systematical results provide a theoretical guidance for the photoelectrochemical devices based on semiconductor nanostructures.

  18. Parametric Quantitative Acoustic Analysis of Conversation Produced by Speakers with Dysarthria and Healthy Speakers

    ERIC Educational Resources Information Center

    Rosen, Kristin M.; Kent, Raymond D.; Delaney, Amy L.; Duffy, Joseph R.

    2006-01-01

    Purpose: This study's main purpose was to (a) identify acoustic signatures of hypokinetic dysarthria (HKD) that are robust to phonetic variation in conversational speech and (b) determine specific characteristics of the variability associated with HKD. Method: Twenty healthy control (HC) participants and 20 participants with HKD associated with…

  19. Troublesome Discourse: Analysis of Native Speaker/Non-Native Speaker Conversation.

    ERIC Educational Resources Information Center

    Fairley, Michael S.

    This paper presents a case study of an episode in a conversation between a native English speaker (the female director of an English language school) and a non-native English speaker (a student apparently with minimal language skills) in which the native speaker is engaged in an extended telling of seemingly crucial information. The troublesome…

  20. Bootstrap Standard Error Estimates in Dynamic Factor Analysis

    ERIC Educational Resources Information Center

    Zhang, Guangjian; Browne, Michael W.

    2010-01-01

    Dynamic factor analysis summarizes changes in scores on a battery of manifest variables over repeated measurements in terms of a time series in a substantially smaller number of latent factors. Algebraic formulae for standard errors of parameter estimates are more difficult to obtain than in the usual intersubject factor analysis because of the…

  1. How Factor Analysis Can Be Used in Classification.

    ERIC Educational Resources Information Center

    Harman, Harry H.

    This is a methodological study that suggests a taxometric technique for objective classification of yeasts. It makes use of the minres method of factor analysis and groups strains of yeast according to their factor profiles. The similarities are judged in the higher-dimensional space determined by the factor analysis, but otherwise rely on the…

  2. Dose conversion and wall correction factors for Fricke dosimetry in high-energy photon beams: analytical model and Monte Carlo calculations.

    PubMed

    Ma, C M; Nahum, A E

    1993-01-01

    This paper presents the dose conversion and wall correction factors for Fricke dosimetry in high-energy photon beams calculated using both an analytical general cavity model and Monte Carlo techniques. The conversion factor is calculated as the ratio of the absorbed dose in water to that in the Fricke dosimeter solution with a water-walled vessel. The wall correction factor accounts for the change in the absorbed dose to the dosimeter solution caused by the inhomogeneous dosimeter wall material. A usercode based on the EGS4 Monte Carlo system, with the application of a correlated sampling variance reduction technique, has been employed in the calculations of these factors and the parameters used in the cavity model. Good agreement has been achieved between the predictions of the model and that obtained by direct Monte Carlo simulation and also with other workers' experiments. It is shown that Fricke dosimeters in common use cannot be considered to be 'large' detectors and therefore 'general cavity theory' should be applied in converting the dose to water. It is confirmed that plastic dosimeter vessels have a negligible wall effect. The wall correction factor for a 1 mm thick Pyrex-walled vessel varies with incident photon energy from 1.001 +/- 0.001 for a 60Co beam to 0.983 +/- 0.001 for a 24 MV (TPR(10)20 = 0.80) photon beam. This implies that previous Fricke measurements with glass-walled vessels should be re-evaluated. PMID:8426871

  3. Dietary patterns and risk of ductal carcinoma of the breast: a factor analysis in Uruguay.

    PubMed

    Ronco, Alvaro L; De Stefani, Eduardo; Deneo-Pellegrini, Hugo; Boffetta, Paolo; Aune, Dagfinn; Silva, Cecilia; Landó, Gabriel; Luaces, María E; Acosta, Gisele; Mendilaharsu, María

    2010-01-01

    Breast cancer (BC) shows very high incidence rates in Uruguayan women. The present factor analysis of ductal carcinoma of the breast, the most frequent histological type of this malignancy both in Uruguay and in the World, was conducted at a prepaid hospital of Montevideo, Uruguay. We identified 111 cases with ductal BC and 222 controls with normal mammograms. A factor analysis was conducted using 39 food groups, allowing retention of six factors analyzed through logistic regression in order to obtain odds ratios (OR) associated with ductal BC. The low fat and non-alcoholic beverage patterns were inversely associated (OR=0.30 and OR=0.45, respectively) with risk. Conversely, the fatty cheese pattern was positively associated (OR=4.17) as well as the fried white meat (OR=2.28) and Western patterns (OR 2.13). Ductal BC shared similar dietary risk patterns as those identified by studies not discriminating between histologic type of breast cancer. PMID:21198261

  4. Ocean thermal conversion (OTEC) project bottom cable protection study: environmental characteristics and hazards analysis

    SciTech Connect

    Chern, C.; Tudor, W.

    1981-10-01

    Seafloor cable-protection criteria and technology as applied to the four proposed OTEC plant sites and cable routes at Hawaii, Puerto Rico, Guam and Florida were examined. Study of environmental characteristics for each site covered: (A) natural factors of location, tide and currents, wind and wave, bottom soil type and seafloor movement; and (B) man-made factors such as ship traffic, fishing activities, ocean mining, government regulations. These characteristics were studied to determine the hazards which are potential sources of damage to a cable system. Hazards include: chafe and corrosion, hydrodynamic forces due to wave and current action, mudslides, earthquakes, trawler and/or dredge action and ship anchors. An analysis of the history of submarine-cable failures was conducted. Included are the probabilities of damage related to water depth. Probabilities become minimal for all hazards in water depths of 1500 feet and more. Chafe and corrosion had the highest probability of causing damage to a seafloor cable compared to the other hazards. Because of the hazards present at all sites, cable burial is recommended as the best means of protection.

  5. Submillimeter Galaxies at z ~ 2: Evidence for Major Mergers and Constraints on Lifetimes, IMF, and CO-H2 Conversion Factor

    NASA Astrophysics Data System (ADS)

    Tacconi, L. J.; Genzel, R.; Smail, I.; Neri, R.; Chapman, S. C.; Ivison, R. J.; Blain, A.; Cox, P.; Omont, A.; Bertoldi, F.; Greve, T.; Förster Schreiber, N. M.; Genel, S.; Lutz, D.; Swinbank, A. M.; Shapley, A. E.; Erb, D. K.; Cimatti, A.; Daddi, E.; Baker, A. J.

    2008-06-01

    We report subarcsecond resolution IRAM PdBI millimeter CO interferometry of four z ~ 2 submillimeter galaxies (SMGs), and sensitive CO(3-2) flux limits toward three z ~ 2 UV/optically selected star-forming galaxies. The new data reveal for the first time spatially resolved CO gas kinematics in the observed SMGs. Two of the SMGs show double or multiple morphologies, with complex, disturbed gas motions. The other two SMGs exhibit CO velocity gradients of ~500 km s-1 across <=0.2'' (1.6 kpc) diameter regions, suggesting that the star-forming gas is in compact, rotating disks. Our data provide compelling evidence that these SMGs represent extreme, short-lived "maximum" star-forming events in highly dissipative mergers of gas-rich galaxies. The resulting high-mass surface and volume densities of SMGs are similar to those of compact quiescent galaxies in the same redshift range and much higher than those in local spheroids. From the ratio of the comoving volume densities of SMGs and quiescent galaxies in the same mass and redshift ranges, and from the comparison of gas exhaustion timescales and stellar ages, we estimate that the SMG phase duration is about 100 Myr. Our analysis of SMGs and optically/UV selected high-redshift star-forming galaxies supports a "universal" Chabrier IMF as being valid over the star-forming history of these galaxies. We find that the 12CO luminosity to total gas mass conversion factors at z ~ 2-3 are probably similar to those assumed at z ~ 0. The implied gas fractions in our sample galaxies range from 20% to 50%. Based on observations obtained at the IRAM Plateau de Bure Interferometer (PdBI). IRAM is funded by the Centre National de la Recherché Scientifique (France), the Max-Planck Gesellschaft (Germany), and the Instituto Geografico Nacional (Spain).

  6. A Bayesian Approach for Multigroup Nonlinear Factor Analysis.

    ERIC Educational Resources Information Center

    Song, Xin-Yuan; Lee, Sik-Yum

    2002-01-01

    Developed a Bayesian approach for a general multigroup nonlinear factor analysis model that simultaneously obtains joint Bayesian estimates of the factor scores and the structural parameters subjected to some constraints across different groups. (SLD)

  7. Full Information Item Factor Analysis of the FCI

    NASA Astrophysics Data System (ADS)

    Hagedorn, Eric

    2010-02-01

    Traditional factor analytical methods, principal factors or principal components analysis, are inappropriate techniques for analyzing dichotomously scored responses to standardized tests or concept inventories because they lead to artifactual factors often referred to as ``difficulty factors.'' Full information item factor analysis (Bock, Gibbons and Muraki, 1988) based on Thurstone's multiple factor model and calculated using marginal maximum likelihood estimation, is an appropriate technique for such analyses. Force Concept Inventory (Hestenes, Wells and Swackhamer, 1992) data from 1582 university students completing an introductory physics course, was analyzed using the full information item factor analysis software TESTFACT v. 4. Analyzing the statistical significance of successive factors added to the model, using chi-squared statistics, led to a six factor model interpretable in terms of the conceptual dimensions of the FCI. )

  8. The sounds of social life: a psychometric analysis of students' daily social environments and natural conversations.

    PubMed

    Mehl, Matthias R; Pennebaker, James W

    2003-04-01

    The natural conversations and social environments of 52 undergraduates were tracked across two 2-day periods separated by 4 weeks using a computerized tape recorder (the Electronically Activated Recorder [EAR]). The EAR was programmed to record 30-s snippets of ambient sounds approximately every 12 min during participants' waking hours. Students' social environments and use of language in their natural conversations were mapped in terms of base rates and temporal stability. The degree of cross-context consistency and between-speaker synchrony in language use was assessed. Students' social worlds as well as their everyday language were highly consistent across time and context. The study sheds light on a methodological blind spot--the sampling of naturalistic social information from an unobtrusive observer's perspective. PMID:12703653

  9. Transglutaminase activity arising from Factor XIIIA is required for stabilization and conversion of plasma fibronectin into matrix in osteoblast cultures.

    PubMed

    Cui, Cui; Wang, Shuai; Myneni, Vamsee D; Hitomi, Kiyotaka; Kaartinen, Mari T

    2014-02-01

    Circulating plasma fibronectin (pFN), produced by hepatocytes, is a major component of the noncollagenous bone matrix where it was recently shown in vivo in mice to control the biomechanical quality as well as the mineral-to-matrix ratio in bone. FN fibrillogenesis is a process generally requiring FN binding to cellular integrins, and cellular tension to elongate and assemble the molecule. Whether soluble pFN undergoes cell-mediated assembly in bone is not fully established. FN is a well-known substrate for transglutaminases (TGs), which are protein-crosslinking enzymes capable of stabilizing macromolecular structures. The role of this modification regarding the function of FN in bone matrix has remained unknown. Osteoblasts express two TGs-transglutaminase 2 and Factor XIIIA-and we have shown that Factor XIIIA is the main TG active during osteoblast differentiation. In the present study, conducted using MC3T3-E1 osteoblast cultures and bone marrow stromal cells, we demonstrate that pFN requires a TG-mediated crosslinking step to form osteoblast matrix in vitro. This modification step is specific for pFN; cellular FN (EDA-FN) does not serve as a TG substrate. Inhibition of pFN assembly using a TG inhibitor, or depletion of pFN from cell culture serum, dramatically decreased total FN matrix assembly in the osteoblast cultures and affected both the quantity and quality of the type I collagen matrix, and decreased lysyl oxidase and alkaline phosphatase levels, resulting in decreased mineralization. Experiments with isozyme-specific substrate peptides showed that FXIIIA is responsible for the crosslinking of pFN. Addition of exogenous preactivated FXIIIA to osteoblast cultures promoted pFN assembly from the media into matrix. Exogenous TG2 had no effect. Analysis of pFN and EDA-FN fibrils by immunofluorescence microscopy demonstrated that they form distinct matrix network, albeit with minor overlap, suggesting different functions for the two FN forms. Further analysis

  10. Development and analysis of a compact low-conversion ratio fast burner reactor.

    SciTech Connect

    Smith, M. A.; Hill, R. N.; Nuclear Engineering Division

    2006-05-12

    This report explores design options for compact fast burner reactors that can achieve low conversion ratios. Operational characteristics and whole-core reactivity coefficients are generated and contrasted with low conversion ratio designs of previous studies. A compact core point design is then selected and detailed reactivity coefficients are displayed and discussed. The effectiveness of fast spectrum systems for actinide transmutation has been well documented. The key advantage of the fast spectrum resides in the severely reduced capture/fission ratios. this inhibits the production of the higher actinides that dominate the long-term radiotoxicity of nuclear waste. In conventional fast burner studies, the transmutation rate was limited by constraints placed on the fuel composition. In an earlier phase of this study the entire range of fuel compositions (including non-uranium fuel) was explored to assess the performance and safety limits of fast burner reactor systems. In this report, similar fuel compositions are utilized for application in compact configurations to achieve conversion ratios below 0.5.

  11. One dimensional full wave analysis of slow-to-fast mode conversion in lower hybrid frequencies

    SciTech Connect

    Jia, Guo-Zhang; Gao, Zhe

    2014-12-15

    The linear conversion from the slow wave to the fast wave in the lower hybrid range of frequencies is analyzed numerically by using the set of field equations describing waves in a cold plane-stratified plasma. The equations are solved as a two-point boundary value problem, where the polarizations of each mode are set consistently in the boundary conditions. The scattering coefficients and the field patterns are obtained for various density profiles. It is shown that, for large density scale length, the results agree well with the traditional cognitions. In contrast, the reflected component and the probable transmitted-converted component from the conversion region, which are neglected in the usual calculations, become significant when the scale length is smaller than the wavelength of the mode. The inclusion of these new components will improve the accuracy of the simulated propagation and deposition for the injected rf power when the conversion process is involved within a sharp-varying density profile. Meanwhile, the accessibility of the incident slow wave for the low frequency case is also affected by the scale length of the density profile.

  12. Analysis of mitochondrial transcription factor A SNPs in alcoholic cirrhosis

    PubMed Central

    TANG, CHUN; LIU, HONGMING; TANG, YONGLIANG; GUO, YONG; LIANG, XIANCHUN; GUO, LIPING; PI, RUXIAN; YANG, JUNTAO

    2014-01-01

    Genetic susceptibility to alcoholic cirrhosis (AC) exists. We previously demonstrated hepatic mitochondrial DNA (mtDNA) damage in patients with AC compared with chronic alcoholics without cirrhosis. Mitochondrial transcription factor A (mtTFA) is central to mtDNA expression regulation and repair; however, it is unclear whether there are specific mtTFA single nucleotide polymorphisms (SNPs) in patients with AC and whether they affect mtDNA repair. In the present study, we screened mtTFA SNPs in patients with AC and analyzed their impact on the copy number of mtDNA in AC. A total of 50 patients with AC, 50 alcoholics without AC and 50 normal subjects were enrolled in the study. SNPs of full-length mtTFA were analyzed using the polymerase chain reaction (PCR) combined with gene sequencing. The hepatic mtTFA mRNA and mtDNA copy numbers were measured using quantitative PCR (qPCR), and mtTFA protein was measured using western blot analysis. A total of 18 mtTFA SNPs specific to patients with AC with frequencies >10% were identified. Two were located in the coding region and 16 were identified in non-coding regions. Conversely, there were five SNPs that were only present in patients with AC and normal subjects and had a frequency >10%. In the AC group, the hepatic mtTFA mRNA and protein levels were significantly lower than those in the other two groups. Moreover, the hepatic mtDNA copy number was significantly lower in the AC group than in the controls and alcoholics without AC. Based on these data, we conclude that AC-specific mtTFA SNPs may be responsible for the observed reductions in mtTFA mRNA, protein levels and mtDNA copy number and they may also increase the susceptibility to AC. PMID:24348767

  13. Source separation in astrophysical maps using independent factor analysis.

    PubMed

    Kuruoğlu, Ercan E; Bedini, Luigi; Paratore, Maria T; Salerno, Emanuele; Tonazzini, Anna

    2003-01-01

    A microwave sky map results from a combination of signals from various astrophysical sources, such as cosmic microwave background radiation, synchrotron radiation and galactic dust radiation. To derive information about these sources, one needs to separate them from the measured maps on different frequency channels. Our insufficient knowledge of the weights to be given to the individual signals at different frequencies makes this a difficult task. Recent work on the problem led to only limited success due to ignoring the noise and to the lack of a suitable statistical model for the sources. In this paper, we derive the statistical distribution of some source realizations, and check the appropriateness of a Gaussian mixture model for them. A source separation technique, namely, independent factor analysis, has been suggested recently in the literature for Gaussian mixture sources in the presence of noise. This technique employs a three layered neural network architecture which allows a simple, hierarchical treatment of the problem. We modify the algorithm proposed in the literature to accommodate for space-varying noise and test its performance on simulated astrophysical maps. We also compare the performances of an expectation-maximization and a simulated annealing learning algorithm in estimating the mixture matrix and the source model parameters. The problem with expectation-maximization is that it does not ensure global optimization, and thus the choice of the starting point is a critical task. Indeed, we did not succeed to reach good solutions for random initializations of the algorithm. Conversely, our experiments with simulated annealing yielded initialization-independent results. The mixing matrix and the means and coefficients in the source model were estimated with a good accuracy while some of the variances of the components in the mixture model were not estimated satisfactorily. PMID:12672442

  14. Analysis of factors affecting angle ANB.

    PubMed

    Hussels, W; Nanda, R S

    1984-05-01

    Cephalometric analyses based on angular and linear measurements have obvious fallacies, which have been discussed in detail by Moyers and Bookstein. However, the clinical application of such an analysis by the orthodontic profession in treatment planning is widely accepted. Variations of angle ANB are commonly used to determine relative jaw relationships in most of the cephalometric evaluations. Several authors, including points A and B influences angle ANB, as does rotational growth of the upper and lower jaws. In addition, the authors point out that growth in a vertical direction (distance N to B) and an increase of the dental height (distance A to B) may contribute to changes in angle ANB. For a Class I relation (Wits = 0 mm), a mathematical formula has been developed which enables the authors to study the geometric influence of angle ANB caused by the following four effects: (1) rotation of the jaws and/or occlusal plane relative to the anterior cranial base; (2) anteroposterior position of N relative to point B, (3) vertical growth (distance N to B); (4) increase in dental height (distance A to B). It was observed that, contrary to the common belief that an ANB angle of 2 +/- 3.0 degrees is considered normal for a skeletal Class I relation, the calculated values of angle ANB will vary widely with changes in these four controlling factors under the same skeletal Class I conditions (Wits = 0 mm). Therefore, in a case under consideration, angle ANB must be corrected for these geometric effects in order to get a proper perspective of the skeletal discrepancy. This is facilitated by comparing the measured ANB angle with the corresponding ANB angle calculated by a formula for a Class I relationship. The corresponding calculated angle ANB can be taken from the tables which are based upon the formula using the same values for SNB, omega (angle between occlusal plane and anterior cranial base), b (which is distance N to B) and a (dental height measured as perpendicular

  15. Conversation analysis at work: detection of conflict in competitive discussions through semi-automatic turn-organization analysis.

    PubMed

    Pesarin, Anna; Cristani, Marco; Murino, Vittorio; Vinciarelli, Alessandro

    2012-10-01

    This study proposes a semi-automatic approach aimed at detecting conflict in conversations. The approach is based on statistical techniques capable of identifying turn-organization regularities associated with conflict. The only manual step of the process is the segmentation of the conversations into turns (time intervals during which only one person talks) and overlapping speech segments (time intervals during which several persons talk at the same time). The rest of the process takes place automatically and the results show that conflictual exchanges can be detected with Precision and Recall around 70% (the experiments have been performed over 6 h of political debates). The approach brings two main benefits: the first is the possibility of analyzing potentially large amounts of conversational data with a limited effort, the second is that the model parameters provide indications on what turn-regularities are most likely to account for the presence of conflict. PMID:22009168

  16. Factors affecting the behavior of bentonite fluids and their in-situ conversion into cement. Final report

    SciTech Connect

    Gueven, N.; Carney, L.L.; Malekahmadi, F.; Lee, L.J.

    1984-11-01

    To develop a basic understanding of the effects of common salts, hydroxides, and other mud additives on the rheology and other functions of bentonite fluids, bentonite fluids containing these additives were autoclaved at the temperature range 70 to 600/sup 0/F, and under a pressure of 17,000 psi. Subsequently, the high-temperature rheology of the fluids was measured with a FANN 50C viscometer. Other fluid properties such as plastic viscosity, gel strength, yield point, pH, CEC, and fluid losses were also determined before and after autoclaving of the fluids. The high-temperature reactions occurring in these fluids were studied with x-ray diffraction and electron microscopy. Another costly problem in drilling technology is related to the poor cement bonding of the casing to the formation. As a solution to this troublesome situation, the in-situ conversion of bentonite fluids into cement has been studied. This conversion has been successfully achieved by the addition of lime to bentonite fluids at and above 300/sup 0/F.

  17. Role of pro-brain-derived neurotrophic factor (proBDNF) to mature BDNF conversion in activity-dependent competition at developing neuromuscular synapses

    PubMed Central

    Je, H. Shawn; Yang, Feng; Ji, Yuanyuan; Nagappan, Guhan; Hempstead, Barbara L.; Lu, Bai

    2012-01-01

    Formation of specific neuronal connections often involves competition between adjacent axons, leading to stabilization of the active terminal, while retraction of the less active ones. The underlying molecular mechanisms remain unknown. We show that activity-dependent conversion of pro–brain-derived neurotrophic factor (proBDNF) to mature (m)BDNF mediates synaptic competition. Stimulation of motoneurons triggers proteolytic conversion of proBDNF to mBDNF at nerve terminals. In Xenopus nerve–muscle cocultures, in which two motoneurons innervate one myocyte, proBDNF-p75NTR signaling promotes retraction of the less active terminal, whereas mBDNF–tyrosine-related kinase B (TrkB) p75NTR (p75 neurotrophin receptor) facilitates stabilization of the active one. Thus, proBDNF and mBDNF may serve as potential “punishment” and “reward” signals for inactive and active terminals, respectively, and activity-dependent conversion of proBDNF to mBDNF may regulate synapse elimination. PMID:23019376

  18. Techno-economic Analysis for the Thermochemical Conversion of Lignocellulosic Biomass to Ethanol via Acetic Acid Synthesis

    SciTech Connect

    Zhu, Yunhua; Jones, Susanne B.

    2009-04-01

    Biomass is a renewable energy resource that can be converted into liquid fuel suitable for transportation applications. As a widely available biomass form, lignocellulosic biomass can have a major impact on domestic transportation fuel supplies and thus help meet the Energy Independence and Security Act renewable energy goals (U.S. Congress 2007). This study performs a techno-economic analysis of the thermo chemical conversion of biomass to ethanol, through methanol and acetic acid, followed by hydrogenation of acetic acid to ethanol. The conversion of syngas to methanol and methanol to acetic acid are well-proven technologies with high conversions and yields. This study was undertaken to determine if this highly selective route to ethanol could provide an already established economically attractive route to ethanol. The feedstock was assumed to be wood chips at 2000 metric ton/day (dry basis). Two types of gasification technologies were evaluated: an indirectly-heated gasifier and a directly-heated oxygen-blown gasifier. Process models were developed and a cost analysis was performed. The carbon monoxide used for acetic acid synthesis from methanol and the hydrogen used for hydrogenation were assumed to be purchased and not derived from the gasifier. Analysis results show that ethanol selling prices are estimated to be $2.79/gallon and $2.81/gallon for the indirectly-heated gasifier and the directly-heated gasifier systems, respectively (1stQ 2008$, 10% ROI). These costs are above the ethanol market price for during the same time period ($1.50 - $2.50/gal). The co-production of acetic acid greatly improves the process economics as shown in the figure below. Here, 20% of the acetic acid is diverted from ethanol production and assumed to be sold as a co-product at the prevailing market prices ($0.40 - $0.60/lb acetic acid), resulting in competitive ethanol production costs.

  19. Approaches and analysis for on-focal-plane analog-to-digital conversion

    NASA Astrophysics Data System (ADS)

    Pain, Bedabrata; Fossum, Eric R.

    1994-06-01

    This paper presents approaches for on-focal-plane analog-to-digital conversion (ADC). Common approaches and architectures for ADC and their utility for on-focal-plane integration are discussed. Candidate approaches are analyzed with respect to required amplifier gain, bandwidth, capacitance matching, noise and offsets as a function of ADC resolution. A column-parallel ADC architecture appears to be an effective compromise of chip area, power, circuit speed and ADC resolution. The discussion is valid for both infrared focal-plane arrays and visible image sensors.

  20. Conversion and correction factors for historical measurements of iodine-131 in Hanford-area vegetation, 1945--1947. Hanford Environmental Dose Reconstruction Project

    SciTech Connect

    Mart, E.I.; Denham, D.H.; Thiede, M.E.

    1993-12-01

    This report is a result of the Hanford Environmental Dose Reconstruction (HEDR) Project whose goal is to estimate the radiation dose that individuals could have received from emissions since 1944 at the U.S. Department of Energy`s (DOE) Hanford Site near Richland, Washington. The HEDR Project is conducted by Battelle, Pacific Northwest Laboratories (BNW). One of the radionuclides emitted that would affect the radiation dose was iodine-131. This report describes in detail the reconstructed conversion and correction factors for historical measurements of iodine-131 in Hanford-area vegetation which was collected from the beginning of October 1945 through the end of December 1947.

  1. FACTOR ANALYSIS OF THE ELKINS HYPNOTIZABILITY SCALE

    PubMed Central

    Elkins, Gary; Johnson, Aimee K.; Johnson, Alisa J.; Sliwinski, Jim

    2015-01-01

    Assessment of hypnotizability can provide important information for hypnosis research and practice. The Elkins Hypnotizability Scale (EHS) consists of 12 items and was developed to provide a time-efficient measure for use in both clinical and laboratory settings. The EHS has been shown to be a reliable measure with support for convergent validity with the Stanford Hypnotic Susceptibility Scale, Form C (r = .821, p < .001). The current study examined the factor structure of the EHS, which was administered to 252 adults (51.3% male; 48.7% female). Average time of administration was 25.8 minutes. Four factors selected on the basis of the best theoretical fit accounted for 63.37% of the variance. The results of this study provide an initial factor structure for the EHS. PMID:25978085

  2. Human factors analysis of plans and procedures

    SciTech Connect

    Wilhelmi, L.

    1991-04-01

    The study of comprehension and retention of print material is a part of what writers call human factors. Some human factors are common knowledge to writers of plans and procedures, but many are not. Federal orders provide some guidance, but that guidance is usually limited to content or order of presentation and does not include style. Style is important in influencing understanding and remembering the content. A writing style that helps produce clear, easily understood plans and procedures is always valuable but it is particularly important for radiological emergency response documents. The procedures are often referred to during emergencies when the emergency staff is under stress and sometimes fatigued by extended work days. The purpose of this paper is to explore some of the human factors (format, sequence of topics, and writing style) that should be considered to make plans and procedures more easily used, understood, and remembered.

  3. Bootstrap Confidence Intervals for Ordinary Least Squares Factor Loadings and Correlations in Exploratory Factor Analysis

    ERIC Educational Resources Information Center

    Zhang, Guangjian; Preacher, Kristopher J.; Luo, Shanhong

    2010-01-01

    This article is concerned with using the bootstrap to assign confidence intervals for rotated factor loadings and factor correlations in ordinary least squares exploratory factor analysis. Coverage performances of "SE"-based intervals, percentile intervals, bias-corrected percentile intervals, bias-corrected accelerated percentile intervals, and…

  4. Exploratory Factor Analysis of a Force Concept Inventory Data Set

    ERIC Educational Resources Information Center

    Scott, Terry F.; Schumayer, Daniel; Gray, Andrew R.

    2012-01-01

    We perform a factor analysis on a "Force Concept Inventory" (FCI) data set collected from 2109 respondents. We address two questions: the appearance of conceptual coherence in student responses to the FCI and some consequences of this factor analysis on the teaching of Newtonian mechanics. We will highlight the apparent conflation of Newton's…

  5. Item Factor Analysis: Current Approaches and Future Directions

    ERIC Educational Resources Information Center

    Wirth, R. J.; Edwards, Michael C.

    2007-01-01

    The rationale underlying factor analysis applies to continuous and categorical variables alike; however, the models and estimation methods for continuous (i.e., interval or ratio scale) data are not appropriate for item-level data that are categorical in nature. The authors provide a targeted review and synthesis of the item factor analysis (IFA)…

  6. Q-Type Factor Analysis of Healthy Aged Men.

    ERIC Educational Resources Information Center

    Kleban, Morton H.

    Q-type factor analysis was used to re-analyze baseline data collected in 1957, on 47 men aged 65-91. Q-type analysis is the use of factor methods to study persons rather than tests. Although 550 variables were originally studied involving psychiatry, medicine, cerebral metabolism and chemistry, personality, audiometry, dichotic and diotic memory,…

  7. 48 CFR 2115.404-71 - Profit analysis factors.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 6 2011-10-01 2011-10-01 false Profit analysis factors... TYPES CONTRACTING BY NEGOTIATION Contract Pricing 2115.404-71 Profit analysis factors. (a) The OPM... inattention or indifference to effective operations, a zero weight. (2) Contract cost risk. OPM will...

  8. 48 CFR 1615.404-70 - Profit analysis factors.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 6 2011-10-01 2011-10-01 false Profit analysis factors... CONTRACTING BY NEGOTIATION Contract Pricing 1615.404-70 Profit analysis factors. (a) OPM contracting officers... indifference to cost control will generally result in a negative weight. (2) Contract cost risk. In...

  9. 48 CFR 2115.404-71 - Profit analysis factors.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 6 2010-10-01 2010-10-01 true Profit analysis factors... TYPES CONTRACTING BY NEGOTIATION Contract Pricing 2115.404-71 Profit analysis factors. (a) The OPM... inattention or indifference to effective operations, a zero weight. (2) Contract cost risk. OPM will...

  10. 48 CFR 2115.404-71 - Profit analysis factors.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 6 2012-10-01 2012-10-01 false Profit analysis factors... TYPES CONTRACTING BY NEGOTIATION Contract Pricing 2115.404-71 Profit analysis factors. (a) The OPM... inattention or indifference to effective operations, a zero weight. (2) Contract cost risk. OPM will...

  11. 48 CFR 2115.404-71 - Profit analysis factors.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 6 2014-10-01 2014-10-01 false Profit analysis factors... TYPES CONTRACTING BY NEGOTIATION Contract Pricing 2115.404-71 Profit analysis factors. (a) The OPM... inattention or indifference to effective operations, a zero weight. (2) Contract cost risk. OPM will...

  12. A Factor Analysis of the BSRI and the PAQ.

    ERIC Educational Resources Information Center

    Edwards, Teresa A.; And Others

    Factor analysis of the Bem Sex Role Inventory (BSRI) and the Personality Attributes Questionnaire (PAQ) was undertaken to study the independence of the masculine and feminine scales within each instrument. Both instruments were administered to undergraduate education majors. Analysis of primary first and second order factors of the BSRI indicated…

  13. The Mixer: Introducing the Concept of Factor Analysis

    ERIC Educational Resources Information Center

    Segrist, Dan J.; Pawlow, Laura A.

    2007-01-01

    This study entailed the development and implementation of a classroom activity designed to introduce students to the concept of factor analysis. We implemented the activity in both a personality theories course and a tests and measurements course. Data suggest that students learned about factor analysis from this activity, while enjoying it.…

  14. Exploratory Factor Analysis of African Self-Consciousness Scale Scores

    ERIC Educational Resources Information Center

    Bhagwat, Ranjit; Kelly, Shalonda; Lambert, Michael C.

    2012-01-01

    This study replicates and extends prior studies of the dimensionality, convergent, and external validity of African Self-Consciousness Scale scores with appropriate exploratory factor analysis methods and a large gender balanced sample (N = 348). Viable one- and two-factor solutions were cross-validated. Both first factors overlapped significantly…

  15. Multigroup Confirmatory Factor Analysis: Locating the Invariant Referent Sets

    ERIC Educational Resources Information Center

    French, Brian F.; Finch, W. Holmes

    2008-01-01

    Multigroup confirmatory factor analysis (MCFA) is a popular method for the examination of measurement invariance and specifically, factor invariance. Recent research has begun to focus on using MCFA to detect invariance for test items. MCFA requires certain parameters (e.g., factor loadings) to be constrained for model identification, which are…

  16. Data structure characterization of miltispectral data using principal component and principal factor analysis

    NASA Technical Reports Server (NTRS)

    Lee, Jae K.; Mausel, Paul W.; Lulla, Kamlesh P.

    1989-01-01

    Both principal component analysis (PCA) and principal factor analysis (PFA) were used to analyze an experimental multispectral data structure in terms of common and unique variance. Only the common variance of the multispectral data was associated with the principal factor, while higher-order principal components were associated with both common and unique variance. The unique variance was found to represent small spectral variations within each cover type as well as noise vectors, and was most abundant in the lower-order principal components. The lower-order principal components can be useful in research designed to discriminate minor physical variations within features, and to highlight localized change when using multitemporal-multispectral data. Conversely, PFA of the multispectral data provided an insight into a great potential for discriminating basic land-cover types by excluding the unique variance which was related to the noise and minor spectral variations.

  17. Evolutionary factor analysis of replicated time series.

    PubMed

    Motta, Giovanni; Ombao, Hernando

    2012-09-01

    In this article, we develop a novel method that explains the dynamic structure of multi-channel electroencephalograms (EEGs) recorded from several trials in a motor-visual task experiment. Preliminary analyses of our data suggest two statistical challenges. First, the variance at each channel and cross-covariance between each pair of channels evolve over time. Moreover, the cross-covariance profiles display a common structure across all pairs, and these features consistently appear across all trials. In the light of these features, we develop a novel evolutionary factor model (EFM) for multi-channel EEG data that systematically integrates information across replicated trials and allows for smoothly time-varying factor loadings. The individual EEGs series share common features across trials, thus, suggesting the need to pool information across trials, which motivates the use of the EFM for replicated time series. We explain the common co-movements of EEG signals through the existence of a small number of common factors. These latent factors are primarily responsible for processing the visual-motor task which, through the loadings, drive the behavior of the signals observed at different channels. The estimation of the time-varying loadings is based on the spectral decomposition of the estimated time-varying covariance matrix. PMID:22364516

  18. An economic analysis of health plan conversions: are they in the public interest?

    PubMed

    Beaulieu, Nancy Dean

    2004-01-01

    Over the last decade, managed-care companies have been consolidating on both a regional and national scale. More recently, nonprofit health plans have been converting to for-profit status, and this conversion has frequently occurred as a step to facilitate merger or acquisition with a for-profit company. Some industry observers attribute these managed-care marketplace trends to an industry shakeout resulting from increased competition in the sector. At the same time, these perceived competitive pressures have led to questions about the long-run viability of nonprofit health plans. Furthermore, some industry and government leaders believe that some nonprofits are already conducting themselves like for-profit health plans and question the state premium tax exemption ordinarily accorded to such plans. This paper examines related health policy issues through the lens of a case study of the proposed conversion of the CareFirst Blue Cross Blue Shield company to a for-profit public-stock company and its merger with the Wellpoint Corporation. Company executives and board members argued that CareFirst lacked access to sufficient capital and faced serious threats to its viability as a financially healthy nonprofit health care company. They also argued that CareFirst and its beneficiaries would benefit from merger through enhanced economies of scale and product-line extensions. Critics of the proposed conversion and merger raised concerns about the adverse impacts on access to care, coverage availability, quality of care, safety-net providers, and the cost of health insurance. Analyses demonstrate that CareFirst wields substantial market power in its local market, that it is unlikely to realize cost savings through expanded economies of scale, and that access to capital concerns are largely driven by the perceived need for further expansion through merger and acquisition. Although it is impossible to predict future changes in quality of care for CareFirst, analyses suggest

  19. Theoretical analysis of solar-driven natural convection energy conversion systems

    SciTech Connect

    Jacobs, E.W.; Lasier, D.D.

    1984-01-01

    This report presents a theoretical study of solar-powered natural convection tower (chimney) performance. Both heated and cooled towers are analyzed; the latter uses evaporating water as the cooling mechanism. The results, which are applicable to any open-cycle configuration, show that the ideal conversion efficiencies of both heated and cooled natural convection towers are linear functions of height. The performance of a heated tower in an adiabatic atmosphere ideally approaches the Carnot efficiency limit of approx. = 3.4%/km (1.0%/1000 ft). Including water pumping requirements, the ideal limit to cooled tower performance is approx. = 2.75%/km (0.85%/1000 ft). Ambient atmospheric conditions such as vertical temperature gradient (lapse rate) and relative humidity can have significantly adverse effects on natural convection tower performance. The combined effects of lapse rate and ambient relative humidity are especially important to cooled natural convection towers.

  20. Chemical and toxicity analysis of leachates from coal conversion solid wastes

    SciTech Connect

    Neufeld, R.D.; Wallach, S.

    1984-03-01

    Coal conversion solid wastes were sieved and leached according to procedures of the ASTM, EPA and a nitric acid extraction procedure designed by the authors. Leachates from all size fractions were analysed for organics, heavy metals and acute toxicity to Daphnia magna. The ASTM-A procedure leached the least material, and the HNO/SUB/3 extraction the most. The quantity of metal leached increased with decreasing particle size. None of the solid waste samples would be considered hazardous according to the Resource Conservation and Recovery Act; however, slag leachates from one type of sample contained Fe at more than 100 times the secondary drinking water standard. EPA leachates and ASTM-A sludge leachates were strongly toxic to Daphnia magna. A linkage was developed between normalised metal concentration, Daphnia magna toxicity and EPA drinking water standards.

  1. EVALUATION OF CORE PHYSICS ANALYSIS METHODS FOR CONVERSION OF THE INL ADVANCED TEST REACTOR TO LOW-ENRICHMENT FUEL

    SciTech Connect

    Mark DeHart; Gray S. Chang

    2012-04-01

    Computational neutronics studies to support the possible conversion of the ATR to LEU are underway. Simultaneously, INL is engaged in a physics methods upgrade project to put into place modern computational neutronics tools for future support of ATR fuel cycle and experiment analysis. A number of experimental measurements have been performed in the ATRC in support of the methods upgrade project, and are being used to validate the new core physics methods. The current computational neutronics work is focused on performance of scoping calculations for the ATR core loaded with a candidate LEU fuel design. This will serve as independent confirmation of analyses that have been performed previously, and will evaluate some of the new computational methods for analysis of a candidate LEU fuel for ATR.

  2. Protein oxidation mediated by heme-induced active site conversion specific for heme-regulated transcription factor, iron response regulator

    PubMed Central

    Kitatsuji, Chihiro; Izumi, Kozue; Nambu, Shusuke; Kurogochi, Masaki; Uchida, Takeshi; Nishimura, Shin-Ichiro; Iwai, Kazuhiro; O’Brian, Mark R.; Ikeda-Saito, Masao; Ishimori, Koichiro

    2016-01-01

    The Bradyrhizobium japonicum transcriptional regulator Irr (iron response regulator) is a key regulator of the iron homeostasis, which is degraded in response to heme binding via a mechanism that involves oxidative modification of the protein. Here, we show that heme-bound Irr activates O2 to form highly reactive oxygen species (ROS) with the “active site conversion” from heme iron to non-heme iron to degrade itself. In the presence of heme and reductant, the ROS scavenging experiments show that Irr generates H2O2 from O2 as found for other hemoproteins, but H2O2 is less effective in oxidizing the peptide, and further activation of H2O2 is suggested. Interestingly, we find a time-dependent decrease of the intensity of the Soret band and appearance of the characteristic EPR signal at g = 4.3 during the oxidation, showing the heme degradation and the successive formation of a non-heme iron site. Together with the mutational studies, we here propose a novel “two-step self-oxidative modification” mechanism, during which O2 is activated to form H2O2 at the heme regulatory motif (HRM) site and the generated H2O2 is further converted into more reactive species such as ·OH at the non-heme iron site in the His-cluster region formed by the active site conversion. PMID:26729068

  3. Analysis of Tissue Factor Positive Microparticles

    PubMed Central

    Key, Nigel S.

    2010-01-01

    There has recently been intense interest in the clinical measurement of tissue factor (TF)-positive microparticles (MPs) in clinical disease states. This interest has been driven by the demonstration of an putative role for circulating TF-positive MPs in animal models of thrombus propagation. Both immunological and functional assays for MP-TF have been described. While each approach has its own advantages and drawbacks, neither has yet been truly established as the ‘gold standard’. Heterogeneity of TF-bearing MPs, such as the variable co-expression of surface phosphatidylserine, may determine not only their procoagulant potential, but also additional properties including rate of clearance from the circulation. PMID:20189224

  4. Methods and analysis of factors impact on the efficiency of the photovoltaic generation

    NASA Astrophysics Data System (ADS)

    Tianze, Li; Xia, Zhang; Chuan, Jiang; Luan, Hou

    2011-02-01

    First of all, the thesis elaborates two important breakthroughs which happened In the field of the application of solar energy in the 1950s.The 21st century the development of solar photovoltaic power generation will have the following characteristics: the continued high growth of industrial development, the significantly reducing cost of the solar cell, the large-scale high-tech development of photovoltaic industries, the breakthroughs of the film battery technology, the rapid development of solar PV buildings integration and combined to the grids. The paper makes principles of solar cells the theoretical analysis. On the basis, we study the conversion efficiency of solar cells, find the factors impact on the efficiency of the photovoltaic generation, solve solar cell conversion efficiency of technical problems through the development of new technology, and open up new ways to improve the solar cell conversion efficiency. Finally, the paper connecting with the practice establishes policies and legislation to the use of encourage renewable energy, development strategy, basic applied research etc.

  5. [Factor Analysis: Principles to Evaluate Measurement Tools for Mental Health].

    PubMed

    Campo-Arias, Adalberto; Herazo, Edwin; Oviedo, Heidi Celina

    2012-09-01

    The validation of a measurement tool in mental health is a complex process that usually starts by estimating reliability, to later approach its validity. Factor analysis is a way to know the number of dimensions, domains or factors of a measuring tool, generally related to the construct validity of the scale. The analysis could be exploratory or confirmatory, and helps in the selection of the items with better performance. For an acceptable factor analysis, it is necessary to follow some steps and recommendations, conduct some statistical tests, and rely on a proper sample of participants. PMID:26572119

  6. Conversion of peripheral blood NK cells to a decidual NK-like phenotype by a cocktail of defined factors

    PubMed Central

    Cerdeira, Ana Sofia; Rajakumar, Augustine; Royle, Caroline M.; Lo, Agnes; Husain, Zaheed; Thadhani, Ravi I.; Sukhatme, Vikas P.; Karumanchi, S. Ananth; Kopcow, Hernan D.

    2013-01-01

    Natural killer (NK) cells that populate the decidua are important regulators of normal placentation. In contrast to peripheral blood NK (pNK) cells, decidual NK cells (dNK) lack cytotoxicity, secrete pro-angiogenic factors and regulate trophoblast invasion. Here we show that exposure to a combination of hypoxia, transforming growth factor beta 1, and a demethylating agent, results in NK cells that express Killer cell Immunoglobulin like Receptors, the dNK cell markers CD9 and CD49a, and dNK pattern of chemokine receptors. These cells secrete vascular endothelial growth factor, a potent pro-angiogenic molecule, display reduced cytotoxicity and promote invasion of human trophoblast cell lines. These findings have potential therapeutic applications for placental disorders associated with altered NK cell biology. PMID:23487420

  7. Analysis of psychological factors for quality assessment of interactive multimodal service

    NASA Astrophysics Data System (ADS)

    Yamagishi, Kazuhisa; Hayashi, Takanori

    2005-03-01

    We proposed a subjective quality assessment model for interactive multimodal services. First, psychological factors of an audiovisual communication service were extracted by using the semantic differential (SD) technique and factor analysis. Forty subjects participated in subjective tests and performed point-to-point conversational tasks on a PC-based TV phone that exhibits various network qualities. The subjects assessed those qualities on the basis of 25 pairs of adjectives. Two psychological factors, i.e., an aesthetic feeling and a feeling of activity, were extracted from the results. Then, quality impairment factors affecting these two psychological factors were analyzed. We found that the aesthetic feeling is mainly affected by IP packet loss and video coding bit rate, and the feeling of activity depends on delay time and video frame rate. We then proposed an opinion model derived from the relationships among quality impairment factors, psychological factors, and overall quality. The results indicated that the estimation error of the proposed model is almost equivalent to the statistical reliability of the subjective score. Finally, using the proposed model, we discuss guidelines for quality design of interactive audiovisual communication services.

  8. Space-based solar power conversion and delivery systems study. Volume 5: Economic analysis

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Space-based solar power conversion and delivery systems are studied along with a variety of economic and programmatic issues relevant to their development and deployment. The costs, uncertainties and risks associated with the current photovoltaic Satellite Solar Power System (SSPS) configuration, and issues affecting the development of an economically viable SSPS development program are addressed. In particular, the desirability of low earth orbit (LEO) and geosynchronous (GEO) test satellites is examined and critical technology areas are identified. The development of SSPS unit production (nth item), and operation and maintenance cost models suitable for incorporation into a risk assessment (Monte Carlo) model (RAM) are reported. The RAM was then used to evaluate the current SSPS configuration expected costs and cost-risk associated with this configuration. By examining differential costs and cost-risk as a function of postulated technology developments, the critical technologies, that is, those which drive costs and/or cost-risk, are identified. It is shown that the key technology area deals with productivity in space, that is, the ability to fabricate and assemble large structures in space, not, as might be expected, with some hardware component technology.

  9. [An epidemiological analysis on the geographic factors of esophageal cancer].

    PubMed

    Song, J

    1992-12-01

    The author collects the data of esophageal cancer mortality (1971-1973) of 78 counties in Hubei Province and the data of topography, climate, soil, rock formation and geochemical elements, including 40 suspected factors. The method of linear correlation and multiple stepwise regression are used for the comprehensive analysis of relation between the geographical factors and esophageal cancer. The result is that four factors metamorphic rock, zinc, copper, chromium are suspected factors. It suggests that the four factors will need future study. PMID:1303310

  10. Functional Analysis and Treatment of Aggression Maintained by Preferred Conversational Topics

    ERIC Educational Resources Information Center

    Roscoe, Eileen M.; Kindle, Arianne E.; Pence, Sacha T.

    2010-01-01

    After an initial functional analysis of a participant's aggression showed unclear outcomes, we conducted preference and reinforcer assessments to identify preferred forms of attention that may maintain problem behavior. Next, we conducted an extended functional analysis that included a modified attention condition. Results showed that the…

  11. Calcineurin Inhibitor Minimization, Conversion, Withdrawal, and Avoidance Strategies in Renal Transplantation: A Systematic Review and Meta-Analysis.

    PubMed

    Sawinski, D; Trofe-Clark, J; Leas, B; Uhl, S; Tuteja, S; Kaczmarek, J L; French, B; Umscheid, C A

    2016-07-01

    Despite their clinical efficacy, concerns about calcineurin inhibitor (CNI) toxicity make alternative regimens that reduce CNI exposure attractive for renal transplant recipients. In this systematic review and meta-analysis, we assessed four CNI immunosuppression strategies (minimization, conversion, withdrawal, and avoidance) designed to reduce CNI exposure and assessed the impact of each on patient and allograft survival, acute rejection and renal function. We evaluated 92 comparisons from 88 randomized controlled trials and found moderate- to high-strength evidence suggesting that minimization strategies result in better clinical outcomes compared with standard-dose regimens; moderate-strength evidence indicating that conversion to a mammalian target of rapamycin inhibitor or belatacept was associated with improved renal function but increased rejection risk; and moderate- to high-strength evidence suggesting planned CNI withdrawal could result in improved renal function despite an association with increased rejection risk. The evidence base for avoidance studies was insufficient to draw meaningful conclusions. The applicability of the review is limited by the large number of studies examining cyclosporine-based strategies and low-risk populations. Additional research is needed with tacrolimus-based regimens and higher risk populations. Moreover, research is necessary to clarify the effect of induction and adjunctive agents in alternative immunosuppression strategies and should include more comprehensive and consistent reporting of patient-centered outcomes. PMID:26990455

  12. Key Factors of Circulation System Analysis and Design

    ERIC Educational Resources Information Center

    McGee, Rob

    1972-01-01

    Explained are basic concepts and components that are common to manual, machine-aided, and computer-based systems, and their significance as key factors in the analysis and design of academic library circulation systems is documented. (2 references) (Author)

  13. Choosing the Optimal Number of Factors in Exploratory Factor Analysis: A Model Selection Perspective

    ERIC Educational Resources Information Center

    Preacher, Kristopher J.; Zhang, Guangjian; Kim, Cheongtag; Mels, Gerhard

    2013-01-01

    A central problem in the application of exploratory factor analysis is deciding how many factors to retain ("m"). Although this is inherently a model selection problem, a model selection perspective is rarely adopted for this task. We suggest that Cudeck and Henly's (1991) framework can be applied to guide the selection process. Researchers must…

  14. Ocean thermal conversion (OTEC) project bottom cable protection study. Analysis and selection of protection techniques

    SciTech Connect

    Not Available

    1981-10-01

    General guidelines and procedures for cable protection are given for the four proposed Ocean Thermal Energy Conversion (OTEC) plant sites and cable routes, together with seafloor scenarios and protection strategies for each site. Burial of the cable below the seafloor is the recommended and best method of protecting OTEC cables from the hazards existing at all sites, namely, chafe and corrosion, hydrodynamic forces, trawler/dredge, and ship anchor. For landslides and earthquakes the only feasible method of protection, although limited, is to provide slack, in the cable, i.e. lay extra length. Trenches for burying the cable are recommended to be constructed a) by blasting through hard bottom at Hawaii for the first nautical mile (n.m.) and at Puerto Rico for the first 0.9 n.m; b)by a plowing machine at Hawaii for the next 0.5 n.m.; c) by a trenching machine at Guam for the first 0.55 n.m.; d) by a trenching /laying machine at Florida for 110 n.m.; and e) by a conventional floating dredge for 15 n.m. For the outshore segments of the cable routes it is recommenced to lay the cable on th seafloor because bottom sediments are soft enough to permit the cable to bury itself. Except for the Florida route, a normal cable laying vessel is recommended for laying the cable from plant site to landfall and for performing the protection details which are temie concrete cover over the cable at Hawaii for 0.5 n.m. and split pipe and rock anchor at Puerto Rico for 0l2 n.m.

  15. Making sense of progressive non-fluent aphasia: an analysis of conversational speech.

    PubMed

    Knibb, Jonathan A; Woollams, Anna M; Hodges, John R; Patterson, Karalyn

    2009-10-01

    The speech of patients with progressive non-fluent aphasia (PNFA) has often been described clinically, but these descriptions lack support from quantitative data. The clinical classification of the progressive aphasic syndromes is also debated. This study selected 15 patients with progressive aphasia on broad criteria, excluding only those with clear semantic dementia. It aimed to provide a detailed quantitative description of their conversational speech, along with cognitive testing and visual rating of structural brain imaging, and to examine which, if any features were consistently present throughout the group; as well as looking for sub-syndromic associations between these features. A consistent increase in grammatical and speech sound errors and a simplification of spoken syntax relative to age-matched controls were observed, though telegraphic speech was rare; slow speech was common but not universal. Almost all patients showed impairments in picture naming, syntactic comprehension and executive function. The degree to which speech was affected was independent of the severity of the other cognitive deficits. A partial dissociation was also observed between slow speech with simplified grammar on the one hand, and grammatical and speech sound errors on the other. Overlap between these sets of impairments was however, the rule rather than the exception, producing continuous variation within a single consistent syndrome. The distribution of atrophy was remarkably variable, with frontal, temporal and medial temporal areas affected, either symmetrically or asymmetrically. The study suggests that PNFA is a coherent, well-defined syndrome and that varieties such as logopaenic progressive aphasia and progressive apraxia of speech may be seen as points in a space of continuous variation within progressive non-fluent aphasia. PMID:19696033

  16. Analysis of magma-thermal conversion of biomass to gaseous fuel

    SciTech Connect

    Gerlach, T.M.

    1982-02-01

    A wide range of magma types and pluton geometries believed to occur within the upper 10 km of the crust provide suitable sources of thermal energy for conversion of water-biomass mixtures to higher quality gaseous fuel. Gaseous fuel can be generated within a magma body, within the hot subsolidus margins of a magma body, or within surface reaction vessels heated by thermal energy derived from a magma body. The composition, amount, and energy content of the fuel gases generated from water-biomass mixtures are not sensitive to the type, age, depth, or temperature of a magma body thermal source. The amount and energy content of the generated fuel is almost entirely a function of the proportion of biomass in the starting mixture. CH/sub 4/ is the main gas that can be generated in important quantities by magma thermal energy under most circumstances. CO is never an important fuel product, and H/sub 2/ generation is very limited. The rates at which gaseous fuels can be generated are strongly dependent on magma type. Fuel generation rates for basaltic magmas are at least 2 to 3 times those for andesitic magmas and 5 to 6 times those for rhyolitic magmas. The highest fuel generation rates, for any particular magma body, will be achieved at the lowest possible reaction vessel operating temperature that does not cause graphite deposition from the water-biomass starting mixture. The energy content of the biomass-derived fuels is considerably greater than that consumed in the generation and refinement process.

  17. Fatigue analysis of WECS (Wind Energy Conversion System) components using a rainflow counting algorithm

    SciTech Connect

    Sutherland, H.J.; Schluter, L.L.

    1990-01-01

    A rainflow counting algorithm'' has been incorporated into the LIFE2 fatigue/fracture analysis code for wind turbines. The count algorithm, with its associated pre- and post-count algorithms, permits the code to incorporate time-series data into its analysis scheme. After a description of the algorithms used here, their use is illustrated by the examination of stress-time histories from the Sandia 34-m Test Bed vertical axis wind turbine. The results of the rainflow analysis are compared and contrasted to previously reported predictions for the service lifetime of the fatigue critical component for this turbine. 14 refs., 8 figs., 3 tabs.

  18. Use of Q-Type Factor Analysis with the Aged.

    ERIC Educational Resources Information Center

    Kleban, Morton H.; And Others

    This paper explores Q-Factor Analysis as a method of organizing data on a large array of variables to describe a group of aged Ss. Forty-seven males, specially selected for their good health (Mean Age: 71.5; SD: 4.8) were measured on 550 biological and behavioral variables. A Q-Factor Analysis was calculated, using a S by variable matrix, which is…

  19. Professional Suitability for Social Work Practice: A Factor Analysis

    ERIC Educational Resources Information Center

    Tam, Dora M. Y.; Coleman, Heather; Boey, Kam-Wing

    2012-01-01

    Objective: The purpose of this study was to identify the underlying dimensions of professional suitability. Method: Data were collected from a province-wide mail-out questionnaire surveying 341 participants from a random sample of registered social workers. Results: The use of an exploratory factor analysis identified a 5-factor solution on…

  20. Exploratory versus Confirmatory Factor Analysis of Collegiate Physical Fitness.

    ERIC Educational Resources Information Center

    Mead, Tim P.; Legg, David L.

    Twenty-one variables believed to be important indicators of health related physical fitness were measured on male and female college students between 1991 and 1993 (n=433). Exploratory and confirmatory factor analytic techniques were used in an attempt to derive important components of physical fitness. The exploratory factor analysis identified…

  1. Determinants of Standard Errors of MLEs in Confirmatory Factor Analysis

    ERIC Educational Resources Information Center

    Yuan, Ke-Hai; Cheng, Ying; Zhang, Wei

    2010-01-01

    This paper studies changes of standard errors (SE) of the normal-distribution-based maximum likelihood estimates (MLE) for confirmatory factor models as model parameters vary. Using logical analysis, simplified formulas and numerical verification, monotonic relationships between SEs and factor loadings as well as unique variances are found.…

  2. An Empirical Analysis of Factors Affecting Honors Program Completion Rates

    ERIC Educational Resources Information Center

    Savage, Hallie; Raehsler, Rod D.; Fiedor, Joseph

    2014-01-01

    One of the most important issues in any educational environment is identifying factors that promote academic success. A plethora of research on such factors exists across most academic fields, involving a wide range of student demographics, and the definition of student success varies across the range of studies published. The analysis in this…

  3. The Constraining of Parameters in Restricted Factor Analysis.

    ERIC Educational Resources Information Center

    Hattie, John; Fraser, Colin

    1988-01-01

    In restricted factor analysis, each element of the matrices of factor loadings and correlations and unique variances and covariances can be constrained. It is argued that the practice of constraining some parameters at zero is not psychologically meaningful. Alternative procedures are presented and illustrated. (TJH)

  4. A Comparative Investigation of Rotation Criteria within Exploratory Factor Analysis

    ERIC Educational Resources Information Center

    Sass, Daniel A.; Schmitt, Thomas A.

    2010-01-01

    Exploratory factor analysis (EFA) is a commonly used statistical technique for examining the relationships between variables (e.g., items) and the factors (e.g., latent traits) they depict. There are several decisions that must be made when using EFA, with one of the more important being choice of the rotation criterion. This selection can be…

  5. Connectivism in Postsecondary Online Courses: An Exploratory Factor Analysis

    ERIC Educational Resources Information Center

    Hogg, Nanette; Lomicky, Carol S.

    2012-01-01

    This study explores 465 postsecondary students' experiences in online classes through the lens of connectivism. Downes' 4 properties of connectivism (diversity, autonomy, interactivity, and openness) were used as the study design. An exploratory factor analysis was performed. This study found a 4-factor solution. Subjects indicated that autonomy…

  6. Using factor analysis to identify neuromuscular synergies during treadmill walking

    NASA Technical Reports Server (NTRS)

    Merkle, L. A.; Layne, C. S.; Bloomberg, J. J.; Zhang, J. J.

    1998-01-01

    Neuroscientists are often interested in grouping variables to facilitate understanding of a particular phenomenon. Factor analysis is a powerful statistical technique that groups variables into conceptually meaningful clusters, but remains underutilized by neuroscience researchers presumably due to its complicated concepts and procedures. This paper illustrates an application of factor analysis to identify coordinated patterns of whole-body muscle activation during treadmill walking. Ten male subjects walked on a treadmill (6.4 km/h) for 20 s during which surface electromyographic (EMG) activity was obtained from the left side sternocleidomastoid, neck extensors, erector spinae, and right side biceps femoris, rectus femoris, tibialis anterior, and medial gastrocnemius. Factor analysis revealed 65% of the variance of seven muscles sampled aligned with two orthogonal factors, labeled 'transition control' and 'loading'. These two factors describe coordinated patterns of muscular activity across body segments that would not be evident by evaluating individual muscle patterns. The results show that factor analysis can be effectively used to explore relationships among muscle patterns across all body segments to increase understanding of the complex coordination necessary for smooth and efficient locomotion. We encourage neuroscientists to consider using factor analysis to identify coordinated patterns of neuromuscular activation that would be obscured using more traditional EMG analyses.

  7. Testing for Heterogeneous Factor Loadings Using Mixtures of Confirmatory Factor Analysis Models

    PubMed Central

    Buzick, Heather M.

    2010-01-01

    The current study assessed the viability of mixture confirmatory factor analysis (CFA) for measurement invariance testing by evaluating the ability of mixture CFA models to identify differences in factor loadings across populations with identical mean structures. Using simulated data from a model with known parameters, convergence rates, parameter recovery, and the power of the likelihood-ratio test were investigated as impacted by sample size, latent class proportions, magnitude of factor loading differences, percentage of non-invariant factor loadings, and pattern of non-invariant factor loadings. Results suggest that mixture CFA models may be a viable option for testing the invariance of factor loadings; however, without differences in latent means and measurement intercepts, results suggest that larger sample sizes, more non-invariant factor loadings, and larger amounts of heterogeneity are needed to successfully estimate parameters and detect differences across latent classes. PMID:21833229

  8. Metric Conversion

    Atmospheric Science Data Center

    2013-03-12

    ... 1,000,000 1,000,000 micrometers nano- 1,000,000,000 1,000,000,000 nanometers ... conversions, see the National Institute of Standards and Technology (NIST) Special Publications: NIST Guide to SI Units: ...

  9. Analysis of LOCA Scenarios in the NIST Research Reactor Before and After Fuel Conversion

    SciTech Connect

    Baek, J. S.; Cheng, L. Y.; Diamond, D.

    2015-08-30

    An analysis has been done of hypothetical loss-of-coolant-accidents (LOCAs) in the research reactor (NBSR) at the National Institute of Standards and Technology (NIST). The purpose of the analysis is to determine if the peak clad temperature remains below the Safety Limit, which is the blister temperature for the fuel. The configuration of the NBSR considered in the analysis is that projected for the future when changes will be made so that shutdown pumps do not operate when a LOCA signal is detected. The analysis was done for the present core with high-enriched uranium (HEU) fuel and with the proposed low-enriched uranium (LEU) fuel that would be used when the NBSR is converted from one to the other. The analysis consists of two parts. The first examines how the water would drain from the primary system following a break and the possibility for the loss of coolant from within the fuel element flow channels. This work is performed using the TRACE system thermal-hydraulic code. The second looks at the fuel clad temperature as a function of time given that the water may have drained from many of the flow channels and the water in the vessel is in a quasi-equilibrium state. The temperature behavior is investigated using the three-dimensional heat conduction code HEATING7.3. The results in all scenarios considered for both HEU and LEU fuel show that the peak clad temperature remains below the blister temperature.

  10. Conditioning analysis of incomplete Cholesky factorizations with orthogonal dropping

    SciTech Connect

    Napov, Artem

    2012-03-16

    The analysis of preconditioners based on incomplete Cholesky factorization in which the neglected (dropped) components are orthogonal to the approximations being kept is presented. General estimate for the condition number of the preconditioned system is given which only depends on the accuracy of individual approximations. The estimate is further improved if, for instance, only the newly computed rows of the factor are modified during each approximation step. In this latter case it is further shown to be sharp. The analysis is illustrated with some existing factorizations in the context of discretized elliptic partial differential equations.

  11. PM₂.₅., EC and OC in atmospheric outflow from the Indo-Gangetic Plain: temporal variability and aerosol organic carbon-to-organic mass conversion factor.

    PubMed

    Srinivas, Bikkina; Sarin, M M

    2014-07-15

    Temporal variability (November'09-March'10) in the mass concentrations of PM2.5, mineral dust, organic carbon and elemental carbon (OC and EC), water-soluble organic carbon (WSOC) and inorganic species (WSIS) has been studied in the atmospheric outflow to the Bay of Bengal from a sampling site [Kharagpur: 22.02°N, 87.11°E] in the Indo-Gangetic Plain (IGP). Based on diagnostic ratios of carbonaceous species [OC/EC ≈ 7.0 ± 2.2, WSOC/OC ≈ 0.52 ± 0.16, and K(+)/EC≈0.48±0.17], we document dominant impact from biomass burning emissions (wood-fuel and post-harvest agricultural-waste burning) in the IGP-outflow. Relatively high concentration of sulphate (SO4(2-) ≈ 6.9-25.3 μg m(-3); SO4(2-)/ΣWSIS=45-77%) and characteristic ratios of nss-SO4(2-)/EC (3.9 ± 2.1) and nss-SO4(2-)/OC (0.61 ± 0.46) provide information on absorption/scattering properties of aerosols. Based on quantitative assessment of individual components of PM2.5, we document aerosol organic carbon-to-organic mass (OC to OM) conversion factor centring at 1.5 ± 0.2 (range: 1.3-2.7) in the atmospheric outflow from IGP. The aerosol composition over the Bay of Bengal shows striking similarity with the diagnostic ratios documented for the IGP-outflow. Relatively high conversion factor for assessing the mass of organic aerosols over the Bay of Bengal (1.1-3.7) provides evidence for their oxidation during long-range atmospheric transport. PMID:24784744

  12. Detecting Outliers in Factor Analysis Using the Forward Search Algorithm

    ERIC Educational Resources Information Center

    Mavridis, Dimitris; Moustaki, Irini

    2008-01-01

    In this article we extend and implement the forward search algorithm for identifying atypical subjects/observations in factor analysis models. The forward search has been mainly developed for detecting aberrant observations in regression models (Atkinson, 1994) and in multivariate methods such as cluster and discriminant analysis (Atkinson, Riani,…

  13. Hydraulic conductivity explored by factor analysis of borehole geophysical data

    NASA Astrophysics Data System (ADS)

    Szabó, Norbert Péter

    2015-08-01

    A multivariate statistical method is presented for providing hydrogeological information on groundwater formations. Factor analysis is applied to borehole logs in Hungary and the USA to estimate the vertical distribution of hydraulic conductivity of rocks intersected by the borehole. Earlier studies showed a strong correlation between a statistical variable extracted by factor analysis and shale volume in primary porosity rocks. Hydraulic conductivity as a related quantity can be derived directly by factor analysis. In the first step, electric and nuclear logs are transformed into factor logs, which are then correlated to hydraulic properties of aquifers. It is shown that a factor explaining the major part of variance of the measured variables is inversely proportional to hydraulic conductivity. By revealing the regression relation between the above quantities, an estimate for hydraulic conductivity can be given along the entire length of the borehole. Synthetic modeling experiments and field cases demonstrate the feasibility of the method, which can be applied both in primary and secondary porosity aquifers. The results of factor analysis show consistence with those of the Kozeny-Carman method and hydraulic aquifer tests. The application of the statistical analysis of well logs together with independent ground geophysical and hydrogeological methods serves a more efficient exploration of groundwater resources.

  14. Exploratory factor analysis of a Force Concept Inventory data set

    NASA Astrophysics Data System (ADS)

    Scott, Terry F.; Schumayer, Daniel; Gray, Andrew R.

    2012-12-01

    We perform a factor analysis on a “Force Concept Inventory” (FCI) data set collected from 2109 respondents. We address two questions: the appearance of conceptual coherence in student responses to the FCI and some consequences of this factor analysis on the teaching of Newtonian mechanics. We will highlight the apparent conflation of Newton’s third law with Newton’s first law in one of the FCI questions and suggest an approach to teaching that may avoid this issue. We also note the absence of a distinct factor interpretable as relating specifically to kinematics. Furthermore, we identify and discuss some of the technical difficulties which may be encountered when performing factor analysis on categorical data sets, such as is the case with FCI data sets.

  15. Elemental and thermo-chemical analysis of oil palm fronds for biomass energy conversion

    NASA Astrophysics Data System (ADS)

    Guangul, Fiseha Mekonnen; Sulaiman, Shaharin Anwar; Raghavan, Vijay R.

    2012-06-01

    Oil palm frond is the most abundant yet untapped biomass waste in Malaysia. This paper investigates the characteristics of raw oil palm fronds and its ash to evaluate its potential utilization as a biomass fuel for gasification process using single throat downdraft gasifier. The morphological nature, elemental content, proximate and ultimate analysis and calorific value were studied. Field emission scanning electron microscopy and x-ray fluorescence were used to investigate the surface morphology, elemental and mineralogical nature of oil palm frond and its ash. The results were compared with other agricultural and forestry biomass wastes. From proximate analysis volatile matter, fixed carbon and ash were found to be 83.5%, 15.2% and 1.3%, respectively on dry basis. From ultimate analysis result values of 44.58%, 4.53%, 0.71% and 0.07% for carbon, hydrogen, nitrogen and sulfur were found respectively on dry basis. Oxygen was determined by difference and found to be 48.81%. The proximate and ultimate analysis results indicate that oil palm frond is better than agricultural wastes and less than most forestry wastes to use as a feedstock in the gasification process in order to get a better quality of syngas. The amount of ash content in OPF was found to be much less than in agricultural wastes and higher than most forestry wastes. From x-ray fluorescence analysis CaO and K2O were found as the major oxides in oil palm fronds and rice husk ash with the amount of 28.46% and 15.71% respectively. The overall results of oil palm fronds were found to be satisfactory to use as a feedstock for the process of gasification.

  16. The helicase-like transcription factor (HLTF) in cancer: loss of function or oncomorphic conversion of a tumor suppressor?

    PubMed

    Dhont, Ludovic; Mascaux, Céline; Belayew, Alexandra

    2016-01-01

    The Helicase-like Transcription Factor (HLTF) belongs to the SWI/SNF family of proteins involved in chromatin remodeling. In addition to its role in gene transcription, HLTF has been implicated in DNA repair, which suggests that this protein acts as a tumor suppressor. Accumulating evidence indicates that HLTF expression is altered in various cancers via two mechanisms: gene silencing through promoter hypermethylation or alternative mRNA splicing, which leads to the expression of truncated proteins that lack DNA repair domains. In either case, the alteration of HLTF expression in cancer has a poor prognosis. In this review, we gathered published clinical and molecular data on HLTF. Our purposes are (a) to address whether HLTF alterations could be considered as cancer drivers or passengers and (b) to determine whether its different functions (transcription or DNA repair) could be diverted in clonal selection during cancer progression. PMID:26472339

  17. Determining Dimensionality of Exercise Readiness Using Exploratory Factor Analysis.

    PubMed

    Strohacker, Kelley; Zakrajsek, Rebecca A

    2016-06-01

    Assessment of "exercise readiness" is a central component to the flexible non-linear periodization (FNLP) method of organizing training workloads, but the underlying factor structure of this construct has not been empirically determined. The purpose of this study was to assess construct dimensionality of exercise readiness using exploratory factor analysis. The result of which serve as initial steps of developing a brief measure of exercise readiness. Participants consisted of students recruited from undergraduate Kinesiology courses at a racially diverse, southern University. Independent, anonymous online survey data were collected across three stages: 1) generation of item pool (n = 290), 2) assessment of face validity and refinement of item pool (n = 168), and 3) exploratory factor analysis (n = 684). A principal axis factor analysis was conducted with 41 items using oblique rotation (promax). Four statistically significant factors, as determined through parallel analysis, explained 61.5% of the variance in exercise readiness. Factor 1 contained items that represented vitality (e.g., lively, revived). Factor 2 items related to physical fatigue (e.g. tired, drained). Factors 3 and 4 were descriptive of, discomfort (e.g. pain, sick) and health (i.e. healthy, fit), respectively. This inductive approach indicates that exercise readiness is comprised of four dimensions: vitality, physical fatigue, discomfort, and health. This finding supports readiness assessment techniques currently recommended for practitioners according to the FNLP model. These results serve as a theoretical foundation upon which to further develop and refine a brief survey instrument to measure exercise readiness. Key pointsAssessment of exercise readiness is a key component in implementing an exercise program based on flexible nonlinear periodization, but the dimensionality of this concept has not been empirically determined.Based on a series of surveys and a robust exploratory factor analysis

  18. Determining Dimensionality of Exercise Readiness Using Exploratory Factor Analysis

    PubMed Central

    Strohacker, Kelley; Zakrajsek, Rebecca A.

    2016-01-01

    Assessment of “exercise readiness” is a central component to the flexible non-linear periodization (FNLP) method of organizing training workloads, but the underlying factor structure of this construct has not been empirically determined. The purpose of this study was to assess construct dimensionality of exercise readiness using exploratory factor analysis. The result of which serve as initial steps of developing a brief measure of exercise readiness. Participants consisted of students recruited from undergraduate Kinesiology courses at a racially diverse, southern University. Independent, anonymous online survey data were collected across three stages: 1) generation of item pool (n = 290), 2) assessment of face validity and refinement of item pool (n = 168), and 3) exploratory factor analysis (n = 684). A principal axis factor analysis was conducted with 41 items using oblique rotation (promax). Four statistically significant factors, as determined through parallel analysis, explained 61.5% of the variance in exercise readiness. Factor 1 contained items that represented vitality (e.g., lively, revived). Factor 2 items related to physical fatigue (e.g. tired, drained). Factors 3 and 4 were descriptive of, discomfort (e.g. pain, sick) and health (i.e. healthy, fit), respectively. This inductive approach indicates that exercise readiness is comprised of four dimensions: vitality, physical fatigue, discomfort, and health. This finding supports readiness assessment techniques currently recommended for practitioners according to the FNLP model. These results serve as a theoretical foundation upon which to further develop and refine a brief survey instrument to measure exercise readiness. Key points Assessment of exercise readiness is a key component in implementing an exercise program based on flexible nonlinear periodization, but the dimensionality of this concept has not been empirically determined. Based on a series of surveys and a robust exploratory factor

  19. The underlying factor structure of National Institutes of Health Stroke scale: an exploratory factor analysis.

    PubMed

    Zandieh, Ali; Kahaki, Zahra Zeynali; Sadeghian, Homa; Pourashraf, Maryam; Parviz, Sara; Ghaffarpour, Majid; Ghabaee, Mojdeh

    2012-03-01

    The underlying structure of National Institutes of Health Stroke Scale (NIHSS) as the most widely used scale in clinical trials has been the focus of little attention. The aim of the current study was to elucidate the clustering pattern of NIHSS items in ischemic stroke patients. A series of 152 consecutive patients with first-ever ischemic strokes admitted to a university affiliated hospital were enrolled. NIHSS score was estimated on admission and correlation coefficients between its items were calculated. Further, exploratory factor analysis was used to study the clustering pattern of NIHSS items. Extinction neglect, visual field, and facial palsy were weakly associated with other NIHSS items. Factor analysis led to a four-factor structure. Factors 1 and 3 were determined by left brain function as items of right arm and leg motor, language and dysarthria loaded on both of them. By contrast, factor 2 reflected right brain involvement. Since visual field and ataxia loaded on factor 4, this factor was primarily associated with posterior strokes. Our study shows that a four-factor structure model is plausible for NIHSS. Further, for the first time, a single distinct factor is identified for posterior strokes. PMID:22023373

  20. Replication Analysis in Exploratory Factor Analysis: What It Is and Why It Makes Your Analysis Better

    ERIC Educational Resources Information Center

    Osborne, Jason W.; Fitzpatrick, David C.

    2012-01-01

    Exploratory Factor Analysis (EFA) is a powerful and commonly-used tool for investigating the underlying variable structure of a psychometric instrument. However, there is much controversy in the social sciences with regard to the techniques used in EFA (Ford, MacCallum, & Tait, 1986; Henson & Roberts, 2006) and the reliability of the outcome.…

  1. Elementary Mode Analysis for the Rational Design of Efficient Succinate Conversion from Glycerol by Escherichia coli

    PubMed Central

    Chen, Zhen; Liu, Hongjuan; Zhang, Jianan; Liu, Dehua

    2010-01-01

    By integrating the restriction of oxygen and redox sensing/regulatory system, elementary mode analysis was used to predict the metabolic potential of glycerol for succinate production by E. coli under either anaerobic or aerobic conditions. It was found that although the theoretical maximum succinate yields under both anaerobic and aerobic conditions are 1.0 mol/mol glycerol, the aerobic condition was considered to be more favorable for succinate production. Although increase of the oxygen concentration would reduce the succinate yield, the calculation suggests that controlling the molar fraction of oxygen to be under 0.65 mol/mol would be beneficial for increasing the succinate productivity. Based on the elementary mode analysis, the rational genetic modification strategies for efficient succinate production under aerobic and anaerobic conditions were obtained, respectively. Overexpressing the phosphoenolpyruvate carboxylase or heterogonous pyruvate carboxylase is considered to be the most efficient strategy to increase the succinate yield. PMID:20886007

  2. Techno-economic Analysis for the Thermochemical Conversion of Biomass to Liquid Fuels

    SciTech Connect

    Zhu, Yunhua; Tjokro Rahardjo, Sandra A.; Valkenburt, Corinne; Snowden-Swan, Lesley J.; Jones, Susanne B.; Machinal, Michelle A.

    2011-06-01

    ). This study is part of an ongoing effort within the Department of Energy to meet the renewable energy goals for liquid transportation fuels. The objective of this report is to present a techno-economic evaluation of the performance and cost of various biomass based thermochemical fuel production. This report also documents the economics that were originally developed for the report entitled “Biofuels in Oregon and Washington: A Business Case Analysis of Opportunities and Challenges” (Stiles et al. 2008). Although the resource assessments were specific to the Pacific Northwest, the production economics presented in this report are not regionally limited. This study uses a consistent technical and economic analysis approach and assumptions to gasification and liquefaction based fuel production technologies. The end fuels studied are methanol, ethanol, DME, SNG, gasoline and diesel.

  3. Space-based solar power conversion and delivery systems (study), engineering analysis

    NASA Technical Reports Server (NTRS)

    Nathan, C. A.

    1975-01-01

    A systems analysis of synchronous, orbit-based power generation and relay systems that could be operational in the 1990's is described along with a comparison with earth-based systems to be operational in the same time frame. Operational and economic requirements for the orbiting systems and near term research activities which will be required to assure feasibility, development, launch and operational capabilities of such systems in the post- 1990 time frame are examined.

  4. Conversion-Integration of MSFC Nonlinear Signal Diagnostic Analysis Algorithms for Realtime Execution of MSFC's MPP Prototype System

    NASA Technical Reports Server (NTRS)

    Jong, Jen-Yi

    1996-01-01

    NASA's advanced propulsion system Small Scale Magnetic Disturbances/Advanced Technology Development (SSME/ATD) has been undergoing extensive flight certification and developmental testing, which involves large numbers of health monitoring measurements. To enhance engine safety and reliability, detailed analysis and evaluation of the measurement signals are mandatory to assess its dynamic characteristics and operational condition. Efficient and reliable signal detection techniques will reduce the risk of catastrophic system failures and expedite the evaluation of both flight and ground test data, and thereby reduce launch turn-around time. During the development of SSME, ASRI participated in the research and development of several advanced non- linear signal diagnostic methods for health monitoring and failure prediction in turbomachinery components. However, due to the intensive computational requirement associated with such advanced analysis tasks, current SSME dynamic data analysis and diagnostic evaluation is performed off-line following flight or ground test with a typical diagnostic turnaround time of one to two days. The objective of MSFC's MPP Prototype System is to eliminate such 'diagnostic lag time' by achieving signal processing and analysis in real-time. Such an on-line diagnostic system can provide sufficient lead time to initiate corrective action and also to enable efficient scheduling of inspection, maintenance and repair activities. The major objective of this project was to convert and implement a number of advanced nonlinear diagnostic DSP algorithms in a format consistent with that required for integration into the Vanderbilt Multigraph Architecture (MGA) Model Based Programming environment. This effort will allow the real-time execution of these algorithms using the MSFC MPP Prototype System. ASRI has completed the software conversion and integration of a sequence of nonlinear signal analysis techniques specified in the SOW for real

  5. Preliminary flashing multiphase flow analysis with application to letdown valves in coal-conversion processes

    SciTech Connect

    Ott, L. J.; Khan, A. A.

    1982-09-01

    As part of the Oak Ridge National Laboratory's technical support to large coal liquefaction projects, attempts have been made to (1) develop the methodology for characterizing and predicting multicomponent, multiphase, non-Newtonian flow behavior within letdown valves and devices, and (2) analyze the fluid flow in the entire letdown region of the process. An engineering model that can be used in the analysis of multicomponent, multiphase, flashing, flowing systems has been developed. A preliminary version of a user-oriented computer code for this model has been developed and is fully described.

  6. Regulation of Pathogen-Triggered Tryptophan Metabolism in Arabidopsis thaliana by MYB Transcription Factors and Indole Glucosinolate Conversion Products.

    PubMed

    Frerigmann, Henning; Piślewska-Bednarek, Mariola; Sánchez-Vallet, Andrea; Molina, Antonio; Glawischnig, Erich; Gigolashvili, Tamara; Bednarek, Paweł

    2016-05-01

    MYB34, MYB51, and MYB122 transcription factors are known as decisive regulators of indolic glucosinolate (IG) biosynthesis with a strong impact on expression of genes encoding CYP79B2 and CYP79B3 enzymes that redundantly convert tryptophan to indole-3-acetaldoxime (IAOx). This intermediate represents a branching point for IG biosynthesis, and pathways leading to camalexin and indole-carboxylic acids (ICA). Here we investigate how these MYBs affect the pathogen-triggered Trp metabolism. Our experiments indicated that these three MYBs affect not only IG production but also constitutive biosynthesis of other IAOx-derived metabolites. Strikingly, the PENETRATION 2 (PEN2)-dependent IG-metabolism products, which are absent in myb34/51/122 and pen2 mutants, were indispensable for full flg22-mediated induction of other IAOx-derived compounds. However, gene induction and accumulation of ICAs and camalexin upon pathogen infection was not compromised in myb34/51/122 plants, despite strongly reduced IG levels. Hence, in comparison with cyp79B2/B3, which lacks all IAOx-derived metabolites, we found myb34/51/122 an ideal tool to analyze IG contribution to resistance against the necrotrophic fungal pathogen Plectosphaerella cucumerina. The susceptibility of myb34/51/122 was similar to that of pen2, but much lower than susceptibility of cyp79B2/B3, indicating that MYB34/51/122 contribute to resistance toward P. cucumerina exclusively through IG biosynthesis, and that PEN2 is the main leaf myrosinase activating IGs in response to microbial pathogens. PMID:26802248

  7. Biological risk factors for suicidal behaviors: a meta-analysis.

    PubMed

    Chang, B P; Franklin, J C; Ribeiro, J D; Fox, K R; Bentley, K H; Kleiman, E M; Nock, M K

    2016-01-01

    Prior studies have proposed a wide range of potential biological risk factors for future suicidal behaviors. Although strong evidence exists for biological correlates of suicidal behaviors, it remains unclear if these correlates are also risk factors for suicidal behaviors. We performed a meta-analysis to integrate the existing literature on biological risk factors for suicidal behaviors and to determine their statistical significance. We conducted a systematic search of PubMed, PsycInfo and Google Scholar for studies that used a biological factor to predict either suicide attempt or death by suicide. Inclusion criteria included studies with at least one longitudinal analysis using a biological factor to predict either of these outcomes in any population through 2015. From an initial screen of 2541 studies we identified 94 cases. Random effects models were used for both meta-analyses and meta-regression. The combined effect of biological factors produced statistically significant but relatively weak prediction of suicide attempts (weighted mean odds ratio (wOR)=1.41; CI: 1.09-1.81) and suicide death (wOR=1.28; CI: 1.13-1.45). After accounting for publication bias, prediction was nonsignificant for both suicide attempts and suicide death. Only two factors remained significant after accounting for publication bias-cytokines (wOR=2.87; CI: 1.40-5.93) and low levels of fish oil nutrients (wOR=1.09; CI: 1.01-1.19). Our meta-analysis revealed that currently known biological factors are weak predictors of future suicidal behaviors. This conclusion should be interpreted within the context of the limitations of the existing literature, including long follow-up intervals and a lack of tests of interactions with other risk factors. Future studies addressing these limitations may more effectively test for potential biological risk factors. PMID:27622931

  8. Advanced view factor analysis method for radiation exchange

    NASA Astrophysics Data System (ADS)

    Park, Sookuk; Tuller, Stanton E.

    2014-03-01

    A raster-based method for determining complex view factor patterns is presented (HURES model). The model uses Johnson and Watson's view factor analysis method for fisheye lens photographs. The entire sphere is divided into 13 different view factors: open sky; sunny and shaded building walls, vegetation (trees) and ground surfaces above and below 1.2 m from the ground surface. The HURES model gave reasonable view factor results in tests at two urban study sites on summer days: downtown Nanaimo, B.C., Canada and Changwon, Republic of Korea. HURES gave better estimates of open sky view factors determined from fisheye lens photographs than did ENVI-met 3.1 and RayMan Pro. However, all three models underestimated sky view factor. For view factor analysis in outdoor urban areas, the 10° interval of rotation angle at 100 m distance of annuli will be suitable settings for three-dimensional computer simulations. The HURES model can be used for the rapid determination of complex view factor patterns which facilitates the analysis of their effects. Examples of how differing view factor patterns can affect human thermal sensation indices are given. The greater proportion of sunny view factors increased the computed predicted mean vote (PMV) by 1.3 on the sunny side of the street compared with the shady side during mid-morning in downtown Nanaimo. In another example, effects of differing amounts of open sky, sunny ground, sunny buildings and vegetation combined to produce only slight differences in PMV and two other human thermal sensation indices, PET and UTCI.

  9. Proteome Analysis of the Effect of Mucoid Conversion on Global Protein Expression in Pseudomonas aeruginosa Strain PAO1 Shows Induction of the Disulfide Bond Isomerase, DsbA

    PubMed Central

    Malhotra, Sonal; Silo-Suh, Laura A.; Mathee, Kalai; Ohman, Dennis E.

    2000-01-01

    Pseudomonas aeruginosa strains that cause chronic pulmonary infections in cystic fibrosis patients typically undergo mucoid conversion. The mucoid phenotype indicates alginate overproduction and is often due to defects in MucA, an antisigma factor that controls the activity of sigma-22 (AlgT [also called AlgU]), which is required for the activation of genes for alginate biosynthesis. In this study we hypothesized that mucoid conversion may be part of a larger response that activates genes other than those for alginate synthesis. To address this, a two-dimensional (2-D) gel analysis was employed to compare total proteins in strain PAO1 to those of its mucA22 derivative, PDO300, in order to identify protein levels enhanced by mucoid conversion. Six proteins that were clearly more abundant in the mucoid strain were observed. The amino termini of such proteins were determined and used to identify the gene products in the genomic database. Proteins involved in alginate biosynthesis were expected among these, and two (AlgA and AlgD) were identified. This result verified that the 2-D gel approach could identify gene products under sigma-22 control and upregulated by mucA mutation. Two other protein spots were also clearly upregulated in the mucA22 background, and these were identified as porin F (an outer membrane protein) and a homologue of DsbA (a disulfide bond isomerase). Single-copy gene fusions were constructed to test whether these proteins were enhanced in the mucoid strain due to increased transcription. The oprF-lacZ fusion showed little difference in levels of expression in the two strains. However, the dsbA-lacZ fusion showed two- to threefold higher expression in PDO300 than in PAO1, suggesting that its promoter was upregulated by the deregulation of sigma-22 activity. A dsbA-null mutant was constructed in PAO1 and shown to have defects predicted for a cell with reduced disulfide bond isomerase activity, namely, reduction in periplasmic alkaline phosphatase

  10. Space-based solar power conversion and delivery systems study. Volume 2: Engineering analysis

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The technical and economic feasibility of Satellite Solar Power Systems was studied with emphasis on the analysis and definition of an integrated strawman configuration concept, from which credible cost data could be estimated. Specifically, system concepts for each of the major subprogram areas were formulated, analyzed, and iterated to the degree necessary for establishing an overall, workable baseline system design. Cost data were estimated for the baseline and used to conduct economic analyses. The baseline concept selected was a 5-GW crystal silicon truss-type photovoltaic configuration, which represented the most mature concept available. The overall results and major findings, and the results of technical analyses performed during the final phase of the study efforts are reported.

  11. Space-based power conversion and power relay systems: Preliminary analysis of alternate systems

    NASA Technical Reports Server (NTRS)

    1976-01-01

    The results are presented of nine months of technical study of non-photovoltaic options for the generation of electricity for terrestrial use by satellite power stations (SPS). A concept for the augmentation of ground-based solar power plants by orbital sunlight reflectors was also studied. Three SPS types having a solar energy source and two which used nuclear reactors were investigated. Data derived for each included: (1) configuration definition, including mass statement; (2) information for use in environmental impact assessment; (3) energy balance (ratio of energy produced to that required to achieve operation), and (4) development and other cost estimates. Cost estimates were dependent upon the total program (development, placement and operation of a number of satellites) which was postulated. This postulation was based upon an analysis of national power capacity trends and guidelines received from MSFC.

  12. Cost-effectiveness analysis of TxDOT CNG fleet conversion, volume 1

    NASA Astrophysics Data System (ADS)

    Euritt, M. A.; Taylor, D. B.; Mahmassani, H.

    1992-08-01

    Increased emphasis on energy efficiency and air quality has resulted in a number of state and federal initiatives examining the use of alternative fuels for motor vehicles. A Texas program for alternate fuels includes compressed natural gas (CNG). Based on analysis of 30-year life-cycle costs, development of a natural gas vehicle (NGV) program for the Texas Department of Transportation (TxDOT) would cost about $47 million (in 1991 dollars). These costs include savings from lower-priced natural gas, infrastructure costs for a fast-fueling station, vehicle costs, and operating costs. The 30-year life-cycle costs translate into an average annual vehicle cost increase of $596, or about 4.9 cents more per vehicle mile of travel.

  13. Comparative analysis of pinewood, peanut shell, and bamboo biomass derived biochars produced via hydrothermal conversion and pyrolysis.

    PubMed

    Huff, Matthew D; Kumar, Sandeep; Lee, James W

    2014-12-15

    Biochars were produced from pinewood, peanut shell, and bamboo biomass through hydrothermal conversion (HTC) at 300 °C and comparatively by slow pyrolysis over a temperature range of 300, 400, and 500 °C. These biochars were characterized by FT-IR, cation exchange capacity (CEC) assay, methylene blue adsorption, as well as proximate and elemental analysis. The experimental results demonstrated higher retained oxygen content in biochars produced at lower pyrolysis temperatures and through HTC, which also correlated to the higher CEC of respective biochars. Furthermore, all types of biochar studied herein were capable of adsorption of methylene blue from solution and the adsorption did not appear to strongly correlate with CEC, indicating that the methylene blue adsorption appears to be dependent more upon the non-electrostatic molecular interactions such as the likely dispersive π-π interactions between the graphene-like sheets of the biochar with the aromatic ring structure of the dye, than the electrostatic CEC. A direct comparison of hydrothermal and pyrolysis converted biochars reveals that biochars produced through HTC have much higher CEC than the biochars produced by slow pyrolysis. Analysis by FT-IR reveals a higher retention of oxygen functional groups in HTC biochars; additionally, there is an apparent trend of increasing aromaticity of the pyrolysis biochars when produced at higher temperatures. The CEC value of the HTC biochar appears correlated with its oxygen functional group content as indicated by the FT-IR measurements and its O:C ratio. PMID:25190598

  14. Sampling and analysis of trace-organic constituents in ambient and workplace air at coal-conversion facilities

    SciTech Connect

    Flotard, R D

    1980-07-01

    A review of the recent literature reveals that current sampling procedures involve the use of glass fiber filters for particulate-sorbed organics and sorbent resins such as Tenax GC and XAD-2 for vapor-phase organics. Ultra trace-organic analysis of air pollutants or particulates may require the collection of a large (1000 to 3000 m/sup 3/) sample by a high volume air sampler. Personal air sampling requires a smaller (approx. = 0.5 m/sup 3/) and a portable collection apparatus. Trapped organic chemicals are recovered by solvent extraction or thermal desorption of the collector. Recovered organics are separated by using liquid chromatography or gas chromatography and are identified by ultraviolet or fluorescence spectroscopy, gas chromatography, or mass spectrometry. For quantification, standards are added to the air stream during sampling or to the filter or resin following sampling. Analysis of the requirement for air sampling in and around coal conversion plants, coupled with the findings of the literature review, indicates that a combined particulate-filter and solvent-extractable-resin sampling unit should be used to collect both particulate-sorbed organics and vapor-phase organics from workplace or ambient plant air. Such a sampler was developed for stationary, moderate-to-high-volume air sampling. Descriptions of the sampler are provided together with sampling efficiency information and recommendations for a sampling procedure.

  15. Personality and coping traits: A joint factor analysis.

    PubMed

    Ferguson, Eamonn

    2001-11-01

    OBJECTIVES: The main objective of this paper is to explore the structural similarities between Eysenck's model of personality and the dimensions of the dispositional COPE. Costa et al. {Costa P., Somerfield, M., & McCrae, R. (1996). Personality and coping: A reconceptualisation. In (pp. 44-61) Handbook of coping: Theory, research and applications. New York: Wiley} suggest that personality and coping behaviour are part of a continuum based on adaptation. If this is the case, there should be structural similarities between measures of personality and coping behaviour. This is tested using a joint factor analysis of personality and coping measures. DESIGN: Cross-sectional survey. METHODS: The EPQ-R and the dispositional COPE were administered to 154 participants, and the data were analysed using joint factor analysis and bivariate associations. RESULTS: The joint factor analysis indicated that these data were best explained by a four-factor model. One factor was primarily unrelated to personality. There was a COPE-neurotic-introvert factor (NI-COPE) containing coping behaviours such as denial, a COPE-extroversion (E-COPE) factor containing behaviours such as seeking social support and a COPE-psychoticism factor (P-COPE) containing behaviours such as alcohol use. This factor pattern, especially for NI- and E-COPE, was interpreted in terms of Gray's model of personality {Gray, J. A. (1987) The psychology of fear and stress. Cambridge: Cambridge University Press}. NI-, E-, and P-COPE were shown to be related, in a theoretically consistent manner, to perceived coping success and perceived coping functions. CONCLUSIONS: The results indicate that there are indeed conceptual links between models of personality and coping. It is argued that future research should focus on identifying coping 'trait complexes'. Implications for practice are discussed. PMID:12614507

  16. Insight on Tafel slopes from a microkinetic analysis of aqueous electrocatalysis for energy conversion.

    PubMed

    Shinagawa, Tatsuya; Garcia-Esparza, Angel T; Takanabe, Kazuhiro

    2015-01-01

    Microkinetic analyses of aqueous electrochemistry involving gaseous H2 or O2, i.e., hydrogen evolution reaction (HER), hydrogen oxidation reaction (HOR), oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), are revisited. The Tafel slopes used to evaluate the rate determining steps generally assume extreme coverage of the adsorbed species (θ≈0 or ≈1), although, in practice, the slopes are coverage-dependent. We conducted detailed kinetic analyses describing the coverage-dependent Tafel slopes for the aforementioned reactions. Our careful analyses provide a general benchmark for experimentally observed Tafel slopes that can be assigned to specific rate determining steps. The Tafel analysis is a powerful tool for discussing the rate determining steps involved in electrocatalysis, but our study also demonstrated that overly simplified assumptions led to an inaccurate description of the surface electrocatalysis. Additionally, in many studies, Tafel analyses have been performed in conjunction with the Butler-Volmer equation, where its applicability regarding only electron transfer kinetics is often overlooked. Based on the derived kinetic description of the HER/HOR as an example, the limitation of Butler-Volmer expression in electrocatalysis is also discussed in this report. PMID:26348156

  17. Insight on Tafel slopes from a microkinetic analysis of aqueous electrocatalysis for energy conversion

    NASA Astrophysics Data System (ADS)

    Shinagawa, Tatsuya; Garcia-Esparza, Angel T.; Takanabe, Kazuhiro

    2015-09-01

    Microkinetic analyses of aqueous electrochemistry involving gaseous H2 or O2, i.e., hydrogen evolution reaction (HER), hydrogen oxidation reaction (HOR), oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), are revisited. The Tafel slopes used to evaluate the rate determining steps generally assume extreme coverage of the adsorbed species (θ ≈ 0 or ≈1), although, in practice, the slopes are coverage-dependent. We conducted detailed kinetic analyses describing the coverage-dependent Tafel slopes for the aforementioned reactions. Our careful analyses provide a general benchmark for experimentally observed Tafel slopes that can be assigned to specific rate determining steps. The Tafel analysis is a powerful tool for discussing the rate determining steps involved in electrocatalysis, but our study also demonstrated that overly simplified assumptions led to an inaccurate description of the surface electrocatalysis. Additionally, in many studies, Tafel analyses have been performed in conjunction with the Butler-Volmer equation, where its applicability regarding only electron transfer kinetics is often overlooked. Based on the derived kinetic description of the HER/HOR as an example, the limitation of Butler-Volmer expression in electrocatalysis is also discussed in this report.

  18. Insight on Tafel slopes from a microkinetic analysis of aqueous electrocatalysis for energy conversion

    PubMed Central

    Shinagawa, Tatsuya; Garcia-Esparza, Angel T.; Takanabe, Kazuhiro

    2015-01-01

    Microkinetic analyses of aqueous electrochemistry involving gaseous H2 or O2, i.e., hydrogen evolution reaction (HER), hydrogen oxidation reaction (HOR), oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), are revisited. The Tafel slopes used to evaluate the rate determining steps generally assume extreme coverage of the adsorbed species (θ ≈ 0 or ≈1), although, in practice, the slopes are coverage-dependent. We conducted detailed kinetic analyses describing the coverage-dependent Tafel slopes for the aforementioned reactions. Our careful analyses provide a general benchmark for experimentally observed Tafel slopes that can be assigned to specific rate determining steps. The Tafel analysis is a powerful tool for discussing the rate determining steps involved in electrocatalysis, but our study also demonstrated that overly simplified assumptions led to an inaccurate description of the surface electrocatalysis. Additionally, in many studies, Tafel analyses have been performed in conjunction with the Butler-Volmer equation, where its applicability regarding only electron transfer kinetics is often overlooked. Based on the derived kinetic description of the HER/HOR as an example, the limitation of Butler-Volmer expression in electrocatalysis is also discussed in this report. PMID:26348156

  19. Analysis of IFR driver fuel hot channel factors

    SciTech Connect

    Ku, J.Y.; Chang, L.K.; Mohr, D.

    1994-03-01

    Thermal-hydraulic uncertainty factors for Integral Fast Reactor (IFR) driver fuels have been determined based primarily on the database obtained from the predecessor fuels used in the IFR prototype, Experimental Breeder Reactor II. The uncertainty factors were applied to the channel factors (HCFs) analyses to obtain separate overall HCFs for fuel and cladding for steady-state analyses. A ``semistatistical horizontal method`` was used in the HCFs analyses. The uncertainty factor of the fuel thermal conductivity dominates the effects considered in the HCFs analysis; the uncertainty in fuel thermal conductivity will be reduced as more data are obtained to expand the currently limited database for the IFR ternary metal fuel (U-20Pu-10Zr). A set of uncertainty factors to be used for transient analyses has also been derived.

  20. Q-mode factor analysis of compositional data

    USGS Publications Warehouse

    Miesch, A.T.

    1976-01-01

    An extended form of the method of Q-mode factor analysis may be used if the rows of the data matrix sum to a constant. The constant row-sum provides a means for scaling the factor model to conform to the units of the original data in such forms as proportions, percentages, or parts per million. The scale factors for an m-factor model are used to derive composition scores and loadings, which lead to the same reproduced data regardless of the choice of reference axes (end-members). Factor-variance diagrams may be constructed to show the proportion of the variance that will be accounted for in each compositional variable by models containing various numbers of end-members. The method may be used to develop a petrologic mixing model by searching for end-members that are geologically plausible. ?? 1976.

  1. Human Factors Vehicle Displacement Analysis: Engineering In Motion

    NASA Technical Reports Server (NTRS)

    Atencio, Laura Ashley; Reynolds, David; Robertson, Clay

    2010-01-01

    While positioned on the launch pad at the Kennedy Space Center, tall stacked launch vehicles are exposed to the natural environment. Varying directional winds and vortex shedding causes the vehicle to sway in an oscillating motion. The Human Factors team recognizes that vehicle sway may hinder ground crew operation, impact the ground system designs, and ultimately affect launch availability . The objective of this study is to physically simulate predicted oscillation envelopes identified by analysis. and conduct a Human Factors Analysis to assess the ability to carry out essential Upper Stage (US) ground operator tasks based on predicted vehicle motion.

  2. Application of Factor Restructuring Analysis in Enterprise Safety Culture Evaluation

    NASA Astrophysics Data System (ADS)

    Wang, Yihong; Xia, Liming; Pan, Jinshuang; Zong, Hengheng

    The enterprise safety culture index system, which mainly consists of enterprise decision-making level, management level, implementation level, and external environmental factor, is constructed based on human errors theory. Then, a corresponding enterprise safety culture evaluation model adapting to the characteristics of this index system is presented with consideration of the constraint condition of data and by taking full use of the advantages of factor system restructuring analysis and principal component analysis in data processing; The model provides an operable way for evaluating the enterprise safety culture. Further, the model is to make up for the gaps of enterprise safety culture evaluation.

  3. Analysis of plug-in hybrid electric vehicle utility factors

    NASA Astrophysics Data System (ADS)

    Bradley, Thomas H.; Quinn, Casey W.

    Plug-in hybrid electric vehicles (PHEVs) are hybrid electric vehicles that can be fueled from both conventional liquid fuels and grid electricity. To represent the total contribution of both of these fuels to the operation, energy use, and environmental impacts of PHEVs, researchers have developed the concept of the utility factor. As standardized in documents such as SAE J1711 and SAE J2841, the utility factor represents the proportion of vehicle distance travelled that can be allocated to a vehicle test condition so as to represent the real-world driving habits of a vehicle fleet. These standards must be used with care so that the results are understood within the context of the assumptions implicit in the standardized utility factors. This study analyzes and derives alternatives to the standard utility factors from the 2001 National Highway Transportation Survey, so as to understand the sensitivity of PHEV performance to assumptions regarding charging frequency, vehicle characteristics, driver characteristics, and means of defining the utility factor. Through analysis of these alternative utility factors, this study identifies areas where analysis, design, and policy development for PHEVs can be improved by alternative utility factor calculations.

  4. Documented Safety Analysis Addendum for the Neutron Radiography Reactor Facility Core Conversion

    SciTech Connect

    Boyd D. Christensen

    2009-05-01

    The Neutron Radiography Reactor Facility (NRAD) is a Training, Research, Isotope Production, General Atomics (TRIGA) reactor which was installed in the Idaho National Laboratory (INL) Hot Fuels Examination Facility (HFEF) at the Materials and Fuels Complex (MFC) in the mid 1970s. The facility provides researchers the capability to examine both irradiated and non-irradiated materials in support of reactor fuel and components programs through non-destructive neutron radiography examination. The facility has been used in the past as one facet of a suite of reactor fuels and component examination facilities available to researchers at the INL and throughout the DOE complex. The facility has also served various commercial research activities in addition to the DOE research and development support. The reactor was initially constructed using Fuel Lifetime Improvement Program (FLIP)- type highly enriched uranium (HEU) fuel obtained from the dismantled Puerto Rico Nuclear Center (PRNC) reactor. In accordance with international non-proliferation agreements, the NRAD core will be converted to a low enriched uranium (LEU) fuel and will continue to utilize the PRNC control rods, control rod drives, startup source, and instrument console as was previously used with the HEU core. The existing NRAD Safety Analysis Report (SAR) was created and maintained in the preferred format of the day, combining sections of both DOE-STD-3009 and Nuclear Regulatory Commission Regulatory Guide 1.70. An addendum was developed to cover the refueling and reactor operation with the LEU core. This addendum follows the existing SAR format combining required formats from both the DOE and NRC. This paper discusses the project to successfully write a compliant and approved addendum to the existing safety basis documents.

  5. Analysis of multi-mode to single-mode conversion at 635 nm and 1550 nm

    NASA Astrophysics Data System (ADS)

    Zamora, Vanessa; Bogatzki, Angelina; Arndt-Staufenbiel, Norbert; Hofmann, Jens; Schröder, Henning

    2016-03-01

    We propose two low-cost and robust optical fiber systems based on the photonic lantern (PL) technology for operating at 635 nm and 1550 nm. The PL is an emerging technology that couples light from a multi-mode (MM) fiber to several single-mode (SM) fibers via a low-loss adiabatic transition. This bundle of SM fibers is observed as a MM fiber system whose spatial modes are the degenerate supermodes of the bundle. The adiabatic transition allows that those supermodes evolve into the modes of the MM fiber. Simulations of the MM fiber end structure and its taper transition have been performed via functional mode solver tools in order to understand the modal evolution in PLs. The modelled design consists of 7 SM fibers inserted into a low-index capillary. The material and geometry of the PLs are chosen such that the supermodes match to the spatial modes of the desired step-index MM fiber in a moderate loss transmission. The dispersion of materials is also considered. These parameters are studied in two PL systems in order to reach a spectral transmission from 450 nm to 1600 nm. Additionally, an analysis of the geometry and losses due to the mismatching of modes is presented. PLs are typically used in the fields of astrophotonics and space photonics. Recently, they are demonstrated as mode converters in telecommunications, especially focusing on spatial division multiplexing. In this study, we show the use of PLs as a promising interconnecting tool for the development of miniaturized spectrometers operating in a broad wavelength range.

  6. Probabilistic Design and Analysis for Robust Design of Advanced Thermoelectric Conversion Systems

    SciTech Connect

    Hendricks, Terry J.; Karri, Naveen K.

    2007-04-01

    ABSTRACT Research work has investigated the impacts and effects of single- and multi-variable stochasticity on optimum thermoelectric (TE) system design for automotive and industrial energy recovery applications because many critical design and environmental parameters input to the design optimization process can be randomly variable. Analysis tools and techniques have been developed to investigate a variety of stochastic behaviors in critical input parameters, including Gaussian, Log-Normal, Weibull, Gamma, or any type of user-defined probability distribution. Recent accomplishments discussed in this work show that Gaussian input probability distributions can create non-Gaussian outcome distributions for optimum TE areas, required cold-side mass flow rates, and expected power generation; optimum deterministically-derived designs (TE areas and cold-side mass flow rates) should be significantly modified in response to stochastically variable inputs; and outcome parameter standard deviations can be quite significant and magnified relative to input parameter standard deviations. Multiple variable stochastic inputs tend to significantly increase the output design parameter variability (i.e., standard deviations). Coupled, interactive effects/impacts of multiple stochastic input parameters in this research have demonstrated that reductions of optimum TE areas by 9-10% relative to deterministic optimum values was warranted in key stochastic analyses cases studied. Reductions in required cold-side mass flow rates may also be justified. Optimum system power output also was characterized by relatively high standard deviations and variability as a result of stochastic input parameter effects on the TE design optimization process, this would be an important consideration when integrating the overall power system design with power management electronics and energy storage subsystems.

  7. Mixture Factor Analysis for Approximating a Nonnormally Distributed Continuous Latent Factor with Continuous and Dichotomous Observed Variables

    ERIC Educational Resources Information Center

    Wall, Melanie M.; Guo, Jia; Amemiya, Yasuo

    2012-01-01

    Mixture factor analysis is examined as a means of flexibly estimating nonnormally distributed continuous latent factors in the presence of both continuous and dichotomous observed variables. A simulation study compares mixture factor analysis with normal maximum likelihood (ML) latent factor modeling. Different results emerge for continuous versus…

  8. Economics of Grassland Conversion

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In this paper we provide an overview of economic factors that contribute to changes in grassland area including the relative profitability of crop and livestock production, effects of land productivity, and effects of conversion costs. We also identify other potential socio-economic influences on gr...

  9. Conversation Classes.

    ERIC Educational Resources Information Center

    Xia, Jiang

    1998-01-01

    Describes an activity for use in the conversational English-as-a-foreign-language classroom. The activity involves having each student say one or two sentences that continues a story being made up as the activity goes along. Students were positive about the activity, because saying only one or two sentences helped them not to feel pressured or…

  10. A Brief History of the Philosophical Foundations of Exploratory Factor Analysis.

    ERIC Educational Resources Information Center

    Mulaik, Stanley A.

    1987-01-01

    Exploratory factor analysis derives its key ideas from many sources, including Aristotle, Francis Bacon, Descartes, Pearson and Yule, and Kant. The conclusions of exploratory factor analysis are never complete without subsequent confirmatory factor analysis. (Author/GDC)

  11. Design, simulation, analysis and optimization of transportation system for a biomass to ethanol conversion plant

    NASA Astrophysics Data System (ADS)

    Ravula, Poorna P.

    The US Department of Energy has set an ambitious goal of replacing 30% of current petroleum consumption with biomass and its products by the year 2030. To achieve this goal, various systems capable of handling biomass at this magnitude have to be designed and built. The transportation system for a cotton gin was studied and modeled with the current management policy (FIFO) used by the gin to gain understanding of a logistic system where the processing plant (gin) pays for the transportation of the feedstock. Alternate management policies for transporting cotton modules showed significant time savings of 24% in days-to-haul. To design a logistics system and management strategy that will minimize the cost of biomass delivery (round bales of switchgrass), a seven-county region in southern Piedmont region of Virginia was selected as the location for a 50 Mg/h bioprocessing plant which operates 24 h/day, 7 days/week. Some of the equipment are not be commercially available and need to be developed. The transport equipment (trucks, loaders and unloaders) was defined and the operational parameters estimated. One hundred and fifty-five secondary storage locations (SSLs) along with a 3.2-km procurement area for each SSL were determined for the region. The travel time from each SSL to the plant was calculated based on a network flow analysis. Seven different policies (strategies) for scheduling loaders were studied. The two key variables were maximum number of trucks required and the maximum at-plant inventory. Five policies were based on "Shortest Travel Time - Longest Travel Time" allocation and two policies were based on "Sector-based" allocation. Policies generating schedules with minimum truck requirement and at-plant storage were simulated. A discrete event simulation model for the logistic system was constructed and the productive operating times for system equipment and inventory was computed. Lowest delivered cost was 14.68/Mg with truck cost averaging 8.44/Mg and

  12. Whole-Genome Analysis of Individual Meiotic Events in Drosophila melanogaster Reveals That Noncrossover Gene Conversions Are Insensitive to Interference and the Centromere Effect

    PubMed Central

    Miller, Danny E.; Smith, Clarissa B.; Kazemi, Nazanin Yeganeh; Cockrell, Alexandria J.; Arvanitakis, Alexandra V.; Blumenstiel, Justin P.; Jaspersen, Sue L.; Hawley, R. Scott

    2016-01-01

    A century of genetic analysis has revealed that multiple mechanisms control the distribution of meiotic crossover events. In Drosophila melanogaster, two significant positional controls are interference and the strongly polar centromere effect. Here, we assess the factors controlling the distribution of crossovers (COs) and noncrossover gene conversions (NCOs) along all five major chromosome arms in 196 single meiotic divisions to generate a more detailed understanding of these controls on a genome-wide scale. Analyzing the outcomes of single meiotic events allows us to distinguish among different classes of meiotic recombination. In so doing, we identified 291 NCOs spread uniformly among the five major chromosome arms and 541 COs (including 52 double crossovers and one triple crossover). We find that unlike COs, NCOs are insensitive to the centromere effect and do not demonstrate interference. Although the positions of COs appear to be determined predominately by the long-range influences of interference and the centromere effect, each chromosome may display a different pattern of sensitivity to interference, suggesting that interference may not be a uniform global property. In addition, unbiased sequencing of a large number of individuals allows us to describe the formation of de novo copy number variants, the majority of which appear to be mediated by unequal crossing over between transposable elements. This work has multiple implications for our understanding of how meiotic recombination is regulated to ensure proper chromosome segregation and maintain genome stability. PMID:26944917

  13. Whole-Genome Analysis of Individual Meiotic Events in Drosophila melanogaster Reveals That Noncrossover Gene Conversions Are Insensitive to Interference and the Centromere Effect.

    PubMed

    Miller, Danny E; Smith, Clarissa B; Kazemi, Nazanin Yeganeh; Cockrell, Alexandria J; Arvanitakas, Alexandra V; Blumenstiel, Justin P; Jaspersen, Sue L; Hawley, R Scott

    2016-05-01

    A century of genetic analysis has revealed that multiple mechanisms control the distribution of meiotic crossover events. In Drosophila melanogaster, two significant positional controls are interference and the strongly polar centromere effect. Here, we assess the factors controlling the distribution of crossovers (COs) and noncrossover gene conversions (NCOs) along all five major chromosome arms in 196 single meiotic divisions to generate a more detailed understanding of these controls on a genome-wide scale. Analyzing the outcomes of single meiotic events allows us to distinguish among different classes of meiotic recombination. In so doing, we identified 291 NCOs spread uniformly among the five major chromosome arms and 541 COs (including 52 double crossovers and one triple crossover). We find that unlike COs, NCOs are insensitive to the centromere effect and do not demonstrate interference. Although the positions of COs appear to be determined predominately by the long-range influences of interference and the centromere effect, each chromosome may display a different pattern of sensitivity to interference, suggesting that interference may not be a uniform global property. In addition, unbiased sequencing of a large number of individuals allows us to describe the formation of de novo copy number variants, the majority of which appear to be mediated by unequal crossing over between transposable elements. This work has multiple implications for our understanding of how meiotic recombination is regulated to ensure proper chromosome segregation and maintain genome stability. PMID:26944917

  14. Medical Paraclinical Standards, Political Economy of Clinic, and Patients’ Clinical Dependency; A Critical Conversation Analysis of Clinical Counseling in South of Iran

    PubMed Central

    Kalateh Sadati, Ahmad; Iman, Mohammad Taghi; Bagheri Lankarani, Kamran

    2014-01-01

    Background: Despite its benefits and importance, clinical counseling affects the patient both psychosocially and socially. Illness labeling not only leads to many problems for patient and his/her family but also it imposes high costs to health care system. Among various factors, doctor-patient relationship has an important role in the clinical counseling and its medical approach. The goal of this study is to evaluate the nature of clinical counseling based on critical approach. Methods: The context of research is the second major medical training center in Shiraz, Iran. In this study, Critical Conversation Analysis was used based on the methodologies of critical theories. Among about 50 consultation meetings digitally recorded, 33 were selected for this study. Results: Results show that the nature of doctor-patient relationship in these cases is based on paternalistic model. On the other hand, in all consultations, the important values that were legitimated with physicians were medical paraclinical standards. Paternalism in one hand and standardization on the other leads to dependency of patients to the clinic. Conclusion: Although we can’t condone the paraclinical standards, clinical counseling and doctor-patient relationship need to reduce its dominance over counseling based on interpretation of human relations, paying attention to social and economical differences of peoples and biosocial and biocultural differences, and focusing on clinical examinations. Also, we need to accept that medicine is an art of interaction that can’t reduce it to instrumental and linear methods of body treatment. PMID:25349858

  15. Improving Your Exploratory Factor Analysis for Ordinal Data: A Demonstration Using FACTOR

    ERIC Educational Resources Information Center

    Baglin, James

    2014-01-01

    Exploratory factor analysis (EFA) methods are used extensively in the field of assessment and evaluation. Due to EFA's widespread use, common methods and practices have come under close scrutiny. A substantial body of literature has been compiled highlighting problems with many of the methods and practices used in EFA, and, in response, many…

  16. Preliminary Neutronics Design and Analysis of D2O Cooled High Conversion PWRs

    SciTech Connect

    Hikaru Hiruta; Gilles Youinou

    2012-09-01

    This report presents a neutronics analysis of tight-pitch D2O-cooled PWRs loaded with MOX fuel and focuses essentially on the Pu breeding potential of such reactors as well as on an important safety parameter, the void coefficient, which has to be negative. It is well known that fast reactors have a better neutron economy and are better suited than thermal reactors to breed fissile material from neutron capture in fertile material. Such fast reactors (e.g. sodium-cooled reactors) usually rely on technologies that are very different from those of existing water-cooled reactors and are probably more expensive. This report investigates another possibility to obtain a fast neutron reactor while still relying mostly on a PWR technology by: (1) Tightening the lattice pitch to reduce the water-to-fuel volume ratio compared to that of a standard PWR. Water-to-fuel volume ratios of between 0.45 and 1 have been considered in this study while a value of about 2 is typical of standard PWRs, (2) Using D2O instead of H2O as a coolant. Indeed, because of its different neutron physics properties, the use of D2O hardens the neutron spectrum to an extent impossible with H2O when used in a tight-pitch lattice. The neutron spectra thus obtained are not as fast as those in sodium-cooled reactor but they can still be characterized as fast compared to that of standard PWR neutron spectra. In the phase space investigated in this study we did not find any configurations that would have, at the same time, a positive Pu mass balance (more Pu at the end than at the beginning of the irradiation) and a negative void coefficient. At this stage, the use of radial blankets has only been briefly addressed whereas the impact of axial blankets has been well defined. For example, with a D2O-to-fuel volume ratio of 0.45 and a core driver height of about 60 cm, the fissile Pu mass balance between the fresh fuel and the irradiated fuel (50 GWd/t) would be about -7.5% (i.e. there are 7.5% fewer fissile Pu

  17. Academic Expectations Stress Inventory: Development, Factor Analysis, Reliability, and Validity

    ERIC Educational Resources Information Center

    Ang, Rebecca P.; Huan, Vivien S.

    2006-01-01

    This article describes the development and initial validation of obtained scores from the Academic Expectations Stress Inventory (AESI), which measures expectations as a source of academic stress in middle and high school Asian students. In the first study, exploratory factor analysis results from 721 adolescents suggested a nine-item scale with…

  18. A Confirmatory Factor Analysis of the Professional Opinion Scale

    ERIC Educational Resources Information Center

    Greeno, Elizabeth J.; Hughes, Anne K.; Hayward, R. Anna; Parker, Karen L.

    2007-01-01

    The Professional Opinion Scale (POS) was developed to measure social work values orientation. Objective: A confirmatory factor analysis was performed on the POS. Method: This cross-sectional study used a mailed survey design with a national random (simple) sample of members of the National Association of Social Workers. Results: The study…

  19. 48 CFR 1615.404-70 - Profit analysis factors.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 6 2013-10-01 2013-10-01 false Profit analysis factors. 1615.404-70 Section 1615.404-70 Federal Acquisition Regulations System OFFICE OF PERSONNEL MANAGEMENT FEDERAL EMPLOYEES HEALTH BENEFITS ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES CONTRACTING BY NEGOTIATION Contract Pricing...

  20. 48 CFR 2115.404-71 - Profit analysis factors.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 6 2013-10-01 2013-10-01 false Profit analysis factors. 2115.404-71 Section 2115.404-71 Federal Acquisition Regulations System OFFICE OF PERSONNEL MANAGEMENT, FEDERAL EMPLOYEES GROUP LIFE INSURANCE FEDERAL ACQUISITION REGULATION CONTRACTING METHODS AND CONTRACT TYPES CONTRACTING BY NEGOTIATION...

  1. Examining Domains of Technological Pedagogical Content Knowledge Using Factor Analysis

    ERIC Educational Resources Information Center

    Shinas, Valerie Harlow; Yilmaz-Ozden, Sule; Mouza, Chrystalla; Karchmer-Klein, Rachel; Glutting, Joseph J.

    2013-01-01

    This study examined the construct validity of the Survey of Preservice Teachers' Knowledge of Teaching and Technology through an exploratory factor analysis using responses from 365 preservice teachers enrolled in an educational technology course in the United States. The participants were completing methods courses and field experience concurrent…

  2. The Hong Psychological Reactance Scale: A Confirmatory Factor Analysis.

    ERIC Educational Resources Information Center

    Thomas, Adrian; Donnell, Alison J.; Buboltz, Walter C., Jr.

    2001-01-01

    Study uses confirmatory factor analysis to assess four models of the Hong Psychological Reactance Scale (HPRS) and attempts to provide psychometric information about the subscales. Results found inadequate fit for Hong's four orthogonal models but sufficient fit for two nonorthogonal models. (Contains 29 references and 3 tables.) (GCP)

  3. A Comparison of Imputation Methods for Bayesian Factor Analysis Models

    ERIC Educational Resources Information Center

    Merkle, Edgar C.

    2011-01-01

    Imputation methods are popular for the handling of missing data in psychology. The methods generally consist of predicting missing data based on observed data, yielding a complete data set that is amiable to standard statistical analyses. In the context of Bayesian factor analysis, this article compares imputation under an unrestricted…

  4. Factor Analysis Studies of the Citizenship Knowledge Test.

    ERIC Educational Resources Information Center

    Napier, John D.

    1982-01-01

    The Citizenship Knowledge Test contains subtests designed to measure subareas of the overall construct of citizenship knowledge. Two factor analysis studies indicated that the test is construct valid. It can, therefore, be used as a general measure of the construct citizenship knowledge. (Author/RM)

  5. Modular Open-Source Software for Item Factor Analysis

    ERIC Educational Resources Information Center

    Pritikin, Joshua N.; Hunter, Micheal D.; Boker, Steven M.

    2015-01-01

    This article introduces an item factor analysis (IFA) module for "OpenMx," a free, open-source, and modular statistical modeling package that runs within the R programming environment on GNU/Linux, Mac OS X, and Microsoft Windows. The IFA module offers a novel model specification language that is well suited to programmatic generation…

  6. A Factor Analysis of Kolb's Revised Learning Style Inventory.

    ERIC Educational Resources Information Center

    Geiger, Marshall A.; And Others

    1992-01-01

    A factor analysis was conducted of scores on the revised Learning Style Inventory of D. A. Kolb from 718 accounting students from 2 large state universities. Results support two bipolar learning dimensions different from those theorized and only one separate learning ability. Caution in interpreting scores is advised. (SLD)

  7. Exploratory factor analysis of the Oral Health Impact Profile.

    PubMed

    John, M T; Reissmann, D R; Feuerstahler, L; Waller, N; Baba, K; Larsson, P; Celebić, A; Szabo, G; Rener-Sitar, K

    2014-09-01

    Although oral health-related quality of life (OHRQoL) as measured by the Oral Health Impact Profile (OHIP) is thought to be multidimensional, the nature of these dimensions is not known. The aim of this report was to explore the dimensionality of the OHIP using the Dimensions of OHRQoL (DOQ) Project, an international study of general population subjects and prosthodontic patients. Using the project's Learning Sample (n = 5173), we conducted an exploratory factor analysis on the 46 OHIP items not specifically referring to dentures for 5146 subjects with sufficiently complete data. The first eigenvalue (27·0) of the polychoric correlation matrix was more than ten times larger than the second eigenvalue (2·6), suggesting the presence of a dominant, higher-order general factor. Follow-up analyses with Horn's parallel analysis revealed a viable second-order, four-factor solution. An oblique rotation of this solution revealed four highly correlated factors that we named Oral Function, Oro-facial Pain, Oro-facial Appearance and Psychosocial Impact. These four dimensions and the strong general factor are two viable hypotheses for the factor structure of the OHIP. PMID:24909881

  8. Identifying influential factors of business process performance using dependency analysis

    NASA Astrophysics Data System (ADS)

    Wetzstein, Branimir; Leitner, Philipp; Rosenberg, Florian; Dustdar, Schahram; Leymann, Frank

    2011-02-01

    We present a comprehensive framework for identifying influential factors of business process performance. In particular, our approach combines monitoring of process events and Quality of Service (QoS) measurements with dependency analysis to effectively identify influential factors. The framework uses data mining techniques to construct tree structures to represent dependencies of a key performance indicator (KPI) on process and QoS metrics. These dependency trees allow business analysts to determine how process KPIs depend on lower-level process metrics and QoS characteristics of the IT infrastructure. The structure of the dependencies enables a drill-down analysis of single factors of influence to gain a deeper knowledge why certain KPI targets are not met.

  9. Metabolic flux analysis model for optimizing xylose conversion into ethanol by the natural C5-fermenting yeast Candida shehatae.

    PubMed

    Bideaux, Carine; Montheard, Julie; Cameleyre, Xavier; Molina-Jouve, Carole; Alfenore, Sandrine

    2016-02-01

    A metabolic flux analysis (MFA) model was developed to optimize the xylose conversion into ethanol using Candida shehatae strain. This metabolic model was compartmented and constructed with xylose as carbon substrate integrating the enzymatic duality of the first step of xylose degradation via an algebraic coefficient. The model included the pentose phosphate pathway, glycolysis, synthesis of major metabolites like ethanol, acetic acid and glycerol, the tricarboxylic acid cycle as well as the respiratory chain, the cofactor balance, and the maintenance. The biomass composition and thus production were integrated considering the major biochemical synthesis reactions from monomers to each constitutive macromolecule (i.e., proteins, lipids, polysaccharides, nucleic acids). The construction of the model resulted into a 122-linear equation system to be resolved. A first experiment allowed was to verify the accuracy of the model by comparing calculated and experimental data. The metabolic model was utilized to determine the theoretical yield taking into account oxido-reductive balance and to optimize ethanol production. The maximal theoretical yield was calculated at 0.62 Cmolethanol/Cmolxylose for an oxygen requirement of 0.33 moloxygen/molxylose linked to the cofactors of the xylose reductase. Cultivations in chemostat mode allowed the fine tuning of both xylose and oxygen uptakes and showed that lower was the oxygen/xylose ratio, higher was the ethanol production yield. The best experimental ethanol production yield (0.51 Cmolethanol/Cmolxylose) was obtained for an oxygen supply of 0.47 moloxygen/molxylose. PMID:26536879

  10. "The goal is to be more flexible"--detailed analysis of goal setting in physiotherapy using a conversation analytic approach.

    PubMed

    Schoeb, Veronika

    2009-12-01

    Standards of practice in physiotherapy require professionals to set goals in collaboration with patients. Some evidence exists regarding outcome, but no studies have investigated the process of goal setting in orthopaedic physiotherapy. The objective of this pilot study is to describe the interaction between professionals and patients in the activity of goal setting. Three physiotherapists in an orthopaedic outpatient department audio-recorded initial patient consultations. Conversation analysis (hereafter CA), a qualitative research method, is used to illustrate participants' interaction in regards to turn taking, how talk is organised, what vocabulary they use and how they respond to each other's utterances. Four distinct phases are found: eliciting patients' preferences; introduction of goal setting activity; formulating goals; and closing the activity of goal setting. Formulating questions to elicit patients' preferences requires considerable effort. Constant adjustment is needed in order to achieve goals acceptable to both participants. Goal setting is time-consuming if the patient is actively involved. Closing of goal setting activity in physiotherapy is comparable to this activity in doctor-patient interaction. In conclusion it is not straightforward to formulate and negotiate treatment goals collaboratively with patients. A balance has to be found between the input of physiotherapists and patients during the process. PMID:19427808

  11. Nonlinear analysis of the pharmacological conversion of sustained atrial fibrillation in conscious goats by the class Ic drug cibenzoline

    NASA Astrophysics Data System (ADS)

    Hoekstra, Bart P. T.; Diks, Cees G. H.; Allessie, Maurits A.; DeGoede, Jacob

    1997-09-01

    random process was rejected using a test for time reversibility. The nonlinear analysis revealed that cibenzoline does not significantly alter the dynamics of sustained AF during pharmacological conversion other than a slowing down of the atrial activation and a somewhat increasing global organization of the atrial activation pattern. The sudden change in the dynamical behavior at cardioversion suggests a mechanism that is reminiscent of a bifurcation.

  12. Confirmatory Factor Analysis of the ADNI Neuropsychological Battery

    PubMed Central

    Park, Lovingly Quitania; Gross, Alden L.; McLaren, Donald; Pa, Judy; Johnson, Julene K.; Mitchell, Meghan; Manly, Jennifer J.

    2012-01-01

    The Alzheimer’s Disease Neuroimaging Initiative (ADNI) is a large multi-center study designed to develop optimized methods for acquiring longitudinal neuroimaging, cognitive, and biomarker measures of AD progression in a large cohort of patients with Alzheimer’s disease (AD), patients with mild cognitive impairment, and healthy controls. Detailed neuropsychological testing was conducted on all participants. We examined the factor structure of the ADNI Neuropsychological Battery across older adults with differing levels of clinical AD severity based on the Clinical Dementia Rating Scale (CDR). Confirmatory factor analysis (CFA) of 23 variables from 10 neuropsychological tests resulted in five factors (memory, language, visuospatial functioning, attention, and executive function/processing speed) that were invariant across levels of cognitive impairment. Thus, these five factors can be used as valid indicators of cognitive function in older adults who are participants in ADNI. PMID:22777078

  13. Limiting values of radionuclide intake and air concentration and dose conversion factors for inhalation, submersion, and ingestion: Federal guidance report No. 11

    SciTech Connect

    Eckerman, K.F.; Wolbarst, A.B.; Richardson, A.C.B.

    1988-09-01

    Radiation protection programs for workers are based, in the United States, on a hierarchy of limitations stemming from Federal guidance approved by the President. This guidance, which consists of principles, policies, and numerical primary guides, is used by Federal agencies as the basis for developing and implementing their own regulatory standards. The primary guides are usually expressed in terms of limiting doses to workers. The protection of workers against taking radioactive materials into the body, however, is accomplished largely through the use of regulations based on derived guides expressed in terms of quantities or concentrations of radionuclides. The values of these derived guides are chosen so as to assure that workers in work environments that conform to them are unlikely to receive radiation doses that exceed the primary guides. The purpose of the present report is to set forth derived guides that are consistent with current Federal radiation protection guidance. They are intended to serve as the basis for regulations setting upper bounds on the inhalation and ingestion of, and submersion in, radioactive materials in the workplace. The report also includes tables of exposure-to-dose conversion factors, for general use in assessing average individual committed doses in any population that is adequately characterized by Reference Man. 38 refs.

  14. Multivariate analysis of prognostic factors in early stage Hodgkin's disease

    SciTech Connect

    Tubiana, M.; Henry-Amar, M.; van der Werf-Messing, B.; Henry, J.; Abbatucci, J.; Burgers, M.; Hayat, M.; Somers, R.; Laugier, A.; Carde, P.

    1985-01-01

    A multivariate analysis of the prognostic factors was carried out with a Cox model on 1,139 patients with clinical Stage I + II Hodgkin's disease included in three controlled clinical trials. The following indicators had been prospectively registered: aged, sex, systemic symptoms, erythrocyte sedimentation, results of staging laparotomy when performed, as well as the date and type of treatment. A linear logistic analysis showed that most of the indicators are interrelated. This emphasizes the necessity of a multivariate analysis in order to assess the independent influence of each of them. The two main prognostic indicators for relapse-free survival are systemic symptoms and/or ESR and number of involved areas. The only significant factor for survival after relapse is age. Sex has a small but significant influence on relapse-free survival. The relative influence of each indicator varies with the type of treatment and these variations may help in understanding the biologic significance of the indicators.

  15. An Exploratory Analysis of Personality Factors Contributed to Suicide Attempts

    PubMed Central

    Kumar, P. N. Suresh; Rajmohan, V.; Sushil, K.

    2013-01-01

    Background: People who attempt suicide have certain individual predispositions, part of which is contributed by personality traits. Aims: The present study was conducted to identify the psycho-sociodemographic and personality related factors contributing to suicide attempts. Materials and Methods: 104 suicide attempters admitted in various departments and referred to the department of psychiatry of IQRAA Hospital formed the study sample. They were evaluated with a self designed socio-demographic proforma, Eysenck's Personality Questionnaire Revised, Albert Einstein College of Medicine-Impulsivity Coping Scale, and Past Feelings and Acts of Violence Scale. Statistics Analysis: The data was initially analyzed by percentage of frequencies. Association between socio-demographic and selected psychological factors was analyzed using t-test and Chi-square test. Intercorrelation among psychological factors was calculated by Pearson's correlation coefficient “r”. Results and Conclusion: Factors such as young age, being married, nuclear family, feeling lonely and burden to family, inability to solve the problems of day to day life, and presence of psychiatric diagnosis and personality traits such as neuroticism, impulsivity, and violence were contributed to suicide attempt. A significant positive relationship between these factors was also identified. Findings of the present study call the attention of mental health professionals to identify these high risk factors in susceptible individuals and to modify these factors to prevent them from attempting suicide. PMID:24379499

  16. External dose-rate conversion factors of radionuclides for air submersion, ground surface contamination and water immersion based on the new ICRP dosimetric setting

    PubMed Central

    Yoo, Song Jae; Jang, Han-Ki; Lee, Jai-Ki; Noh, Siwan; Cho, Gyuseong

    2013-01-01

    For the assessment of external doses due to contaminated environment, the dose-rate conversion factors (DCFs) prescribed in Federal Guidance Report 12 (FGR 12) and FGR 13 have been widely used. Recently, there were significant changes in dosimetric models and parameters, which include the use of the Reference Male and Female Phantoms and the revised tissue weighting factors, as well as the updated decay data of radionuclides. In this study, the DCFs for effective and equivalent doses were calculated for three exposure settings: skyshine, groundshine and water immersion. Doses to the Reference Phantoms were calculated by Monte Carlo simulations with the MCNPX 2.7.0 radiation transport code for 26 mono-energy photons between 0.01 and 10 MeV. The transport calculations were performed for the source volume within the cut-off distances practically contributing to the dose rates, which were determined by a simplified calculation model. For small tissues for which the reduction of variances are difficult, the equivalent dose ratios to a larger tissue (with lower statistical errors) nearby were employed to make the calculation efficient. Empirical response functions relating photon energies, and the organ equivalent doses or the effective doses were then derived by the use of cubic-spline fitting of the resulting doses for 26 energy points. The DCFs for all radionuclides considered important were evaluated by combining the photon emission data of the radionuclide and the empirical response functions. Finally, contributions of accompanied beta particles to the skin equivalent doses and the effective doses were calculated separately and added to the DCFs. For radionuclides considered in this study, the new DCFs for the three exposure settings were within ±10 % when compared with DCFs in FGR 13. PMID:23542764

  17. Conversational sensing

    NASA Astrophysics Data System (ADS)

    Preece, Alun; Gwilliams, Chris; Parizas, Christos; Pizzocaro, Diego; Bakdash, Jonathan Z.; Braines, Dave

    2014-05-01

    Recent developments in sensing technologies, mobile devices and context-aware user interfaces have made it pos- sible to represent information fusion and situational awareness for Intelligence, Surveillance and Reconnaissance (ISR) activities as a conversational process among actors at or near the tactical edges of a network. Motivated by use cases in the domain of Company Intelligence Support Team (CoIST) tasks, this paper presents an approach to information collection, fusion and sense-making based on the use of natural language (NL) and controlled nat- ural language (CNL) to support richer forms of human-machine interaction. The approach uses a conversational protocol to facilitate a ow of collaborative messages from NL to CNL and back again in support of interactions such as: turning eyewitness reports from human observers into actionable information (from both soldier and civilian sources); fusing information from humans and physical sensors (with associated quality metadata); and assisting human analysts to make the best use of available sensing assets in an area of interest (governed by man- agement and security policies). CNL is used as a common formal knowledge representation for both machine and human agents to support reasoning, semantic information fusion and generation of rationale for inferences, in ways that remain transparent to human users. Examples are provided of various alternative styles for user feedback, including NL, CNL and graphical feedback. A pilot experiment with human subjects shows that a prototype conversational agent is able to gather usable CNL information from untrained human subjects.

  18. Conversational sensemaking

    NASA Astrophysics Data System (ADS)

    Preece, Alun; Webberley, Will; Braines, Dave

    2015-05-01

    Recent advances in natural language question-answering systems and context-aware mobile apps create opportunities for improved sensemaking in a tactical setting. Users equipped with mobile devices act as both sensors (able to acquire information) and effectors (able to act in situ), operating alone or in collectives. The currently- dominant technical approaches follow either a pull model (e.g. Apple's Siri or IBM's Watson which respond to users' natural language queries) or a push model (e.g. Google's Now which sends notifications to a user based on their context). There is growing recognition that users need more flexible styles of conversational interaction, where they are able to freely ask or tell, be asked or told, seek explanations and clarifications. Ideally such conversations should involve a mix of human and machine agents, able to collaborate in collective sensemaking activities with as few barriers as possible. Desirable capabilities include adding new knowledge, collaboratively building models, invoking specific services, and drawing inferences. As a step towards this goal, we collect evidence from a number of recent pilot studies including natural experiments (e.g. situation awareness in the context of organised protests) and synthetic experiments (e.g. human and machine agents collaborating in information seeking and spot reporting). We identify some principles and areas of future research for "conversational sensemaking".

  19. Safer approaches and landings: A multivariate analysis of critical factors

    NASA Astrophysics Data System (ADS)

    Heinrich, Durwood J.

    The approach-and-landing phases of flight represent 27% of mission time while resulting in 61 of the accidents and 39% of the fatalities. The landing phase itself represents only 1% of flight time but claims 45% of the accidents. Inadequate crew situation awareness (SA), crew resource management (CRM), and crew decision-making (DM) have been implicated in 51%, 63%, and 73% respectively of these accidents. The human factors constructs of SA, CRM, and DM were explored; a comprehensive definition of SA was proposed; and a "proactive defense" safety strategy was recommended. Data from a 1997 analysis of worldwide fatal accidents by the Flight Safety Foundation (FSF) Approach-and-Landing Accident Reduction (ALAR) Task Force was used to isolate crew- and weather-related causal factors that lead to approach-and-landing accidents (ALAs). Logistic regression and decision tree analysis were used on samplings of NASA's Aviation Safety Reporting System (ASRS) incident records ("near misses") and the National Transportation Safety Board's (NTSB) accident reports to examine hypotheses regarding factors and factor combinations that can dramatically increase the opportunity for accidents. An effective scale of risk factors was introduced for use by crews to proactively counter safety-related error-chain situations.

  20. Component Analysis versus Common Factor Analysis: Some issues in Selecting an Appropriate Procedure.

    PubMed

    Velicer, W F; Jackson, D N

    1990-01-01

    Should one do a component analysis or a factor analysis? The choice is not obvious, because the two broad classes of procedures serve a similar purpose, and share many important mathematical characteristics. Despite many textbooks describing common factor analysis as the preferred procedure, principal component analysis has been the most widely applied. Here we summarize relevant information for the prospective factor/component analyst. First, we discuss the key algebraic similarities and differences. Next, we analyze a number of theoretical and practical issues. The more practical aspects include: the degree of numeric similarity between solutions from the two methods, some common rules for the number of factors to be retained, effects resulting from overextraction, problems with improper solutions, and comparisons in computational efficiency. Finally, we review some broader theoretical issues: the factor indeterminacy issue, the differences between exploratory and confirmatory procedures, and the issue of latent versus manifest variables. PMID:26741964

  1. Solar energy conversion through the interaction of plasmons with tunnel junctions. Part A: Solar cell analysis. Part B: Photoconductor analysis

    NASA Technical Reports Server (NTRS)

    Welsh, P. E.; Schwartz, R. J.

    1988-01-01

    A solar cell utilizing guided optical waves and tunnel junctions was analyzed to determine its feasibility. From this analysis, it appears that the limits imposed upon conventional multiple cell systems also limit this solar cell. Due to this limitation, it appears that the relative simplicity of the conventional multiple cell systems over the solar cell make the conventional multiple cell systems the more promising candidate for improvement. It was discovered that some superlattice structures studied could be incorporated into an infrared photodetector. This photoconductor appears to be promising as a high speed, sensitive (high D sup star sub BLIP) detector in the wavelength range from 15 to over 100 micrometers.

  2. The future of dynamic factor analysis in psychology and biomedicine.

    PubMed

    Molenaar, P C M

    2006-01-01

    The currently dominant approach to statistical analysis in psychology and biomedicine is based on analysis of inter-individual variation. Differences between subjects drawn from a population of subjects provide the information to make inferences about states of affairs at the population level (e.g., mean and/or covariance structure). Recently it has been shown that in general the inferred states of affairs at the population level do not apply at the level of intra-individual variation characterizing the life trajectories of individual subjects making up the population. This is a direct consequence of the so-called classical ergodic theorems of Birkhoff and Wiener which has important implications for the way in which psychological and biomedical processes have to be analyzed. The classical ergodic theorems are introduced below in order to show the necessity of using an alternative approach which is valid for the analysis of intra-individual variation. This approach has to be based on single-subject time series analysis. Next an overview is presented of dynamic factor models for the analysis of multivariate time series and the various ways to fit these models to the data. We then turn to an empirical application of factor analysis of personality data obtained in a replicated time series design, showing substantial heterogeneity in intra-individual factorial personality structure. The next topic is entirely innovative--for the first time I present my new dynamic factor model for the analysis of nonstationary time series. In the conclusion I will sketch some biomedical research initiatives in which this new model will be used. PMID:17124797

  3. Performance analysis of parallel supernodal sparse LU factorization

    SciTech Connect

    Grigori, Laura; Li, Xiaoye S.

    2004-02-05

    We investigate performance characteristics for the LU factorization of large matrices with various sparsity patterns. We consider supernodal right-looking parallel factorization on a bi-dimensional grid of processors, making use of static pivoting. We develop a performance model and we validate it using the implementation in SuperLU-DIST, the real matrices and the IBM Power3 machine at NERSC. We use this model to obtain performance bounds on parallel computers, to perform scalability analysis and to identify performance bottlenecks. We also discuss the role of load balance and data distribution in this approach.

  4. A human factors analysis of EVA time requirements

    NASA Technical Reports Server (NTRS)

    Pate, D. W.

    1996-01-01

    Human Factors Engineering (HFE), also known as Ergonomics, is a discipline whose goal is to engineer a safer, more efficient interface between humans and machines. HFE makes use of a wide range of tools and techniques to fulfill this goal. One of these tools is known as motion and time study, a technique used to develop time standards for given tasks. A human factors motion and time study was initiated with the goal of developing a database of EVA task times and a method of utilizing the database to predict how long an ExtraVehicular Activity (EVA) should take. Initial development relied on the EVA activities performed during the STS-61 mission (Hubble repair). The first step of the analysis was to become familiar with EVAs and with the previous studies and documents produced on EVAs. After reviewing these documents, an initial set of task primitives and task time modifiers was developed. Videotaped footage of STS-61 EVAs were analyzed using these primitives and task time modifiers. Data for two entire EVA missions and portions of several others, each with two EVA astronauts, was collected for analysis. Feedback from the analysis of the data will be used to further refine the primitives and task time modifiers used. Analysis of variance techniques for categorical data will be used to determine which factors may, individually or by interactions, effect the primitive times and how much of an effect they have.

  5. Factor analysis and predictive validity of microcomputer-based tests.

    PubMed

    Kennedy, R S; Baltzley, D R; Turnage, J J; Jones, M B

    1989-12-01

    11 tests were selected from two microcomputer-based performance test batteries because previously these tests exhibited rapid stability (less than 10 min, of practice) and high retest reliability efficiencies (r greater than 0.707 for each 3 min. of testing). The battery was administered three times to each of 108 college students (48 men and 60 women) and a factor analysis was performed. Two of the three identified factors appear to be related to information processing ("encoding" and "throughput/decoding"), and the third named an "output/speed" factor. The spatial, memory, and verbal tests loaded on the "encoding" factor and included Grammatical Reasoning, Pattern Comparison, Continuous Recall, and Matrix Rotation. The "throughput/decoding" tests included perceptual/numerical tests like Math Processing, Code Substitution, and Pattern Comparison. The output speed factor was identified by Tapping and Reaction Time tests. The Wonderlic Personnel Test was group administered before the first and after the last administration of the performance tests. The multiple Rs in the total sample between combined Wonderlic as a criterion and less than 5 min. of microcomputer testing on Grammatical Reasoning and Math Processing as predictors ranged between 0.41 and 0.52 on the three test administrations. Based on these results, the authors recommend a core battery which, if time permits, would consist of two tests from each factor. Such a battery is now known to permit stable, reliable, and efficient assessment. PMID:2622715

  6. Factor analysis and predictive validity of microcomputer-based tests

    NASA Technical Reports Server (NTRS)

    Kennedy, R. S.; Baltzley, D. R.; Turnage, J. J.; Jones, M. B.

    1989-01-01

    11 tests were selected from two microcomputer-based performance test batteries because previously these tests exhibited rapid stability (less than 10 min, of practice) and high retest reliability efficiencies (r greater than 0.707 for each 3 min. of testing). The battery was administered three times to each of 108 college students (48 men and 60 women) and a factor analysis was performed. Two of the three identified factors appear to be related to information processing ("encoding" and "throughput/decoding"), and the third named an "output/speed" factor. The spatial, memory, and verbal tests loaded on the "encoding" factor and included Grammatical Reasoning, Pattern Comparison, Continuous Recall, and Matrix Rotation. The "throughput/decoding" tests included perceptual/numerical tests like Math Processing, Code Substitution, and Pattern Comparison. The output speed factor was identified by Tapping and Reaction Time tests. The Wonderlic Personnel Test was group administered before the first and after the last administration of the performance tests. The multiple Rs in the total sample between combined Wonderlic as a criterion and less than 5 min. of microcomputer testing on Grammatical Reasoning and Math Processing as predictors ranged between 0.41 and 0.52 on the three test administrations. Based on these results, the authors recommend a core battery which, if time permits, would consist of two tests from each factor. Such a battery is now known to permit stable, reliable, and efficient assessment.

  7. THE CO-TO-H{sub 2} CONVERSION FACTOR AND DUST-TO-GAS RATIO ON KILOPARSEC SCALES IN NEARBY GALAXIES

    SciTech Connect

    Sandstrom, K. M.; Walter, F.; Leroy, A. K.; Bolatto, A. D.; Wolfire, M.; Croxall, K. V.; Crocker, A.; Draine, B. T.; Aniano, G.; Wilson, C. D.; Calzetti, D.; Kennicutt, R. C.; Galametz, M.; Donovan Meyer, J.; Usero, A.; Bigiel, F.; Brinks, E.; De Blok, W. J. G.; Dale, D.; Engelbracht, C. W.; and others

    2013-11-01

    We present ∼kiloparsec spatial resolution maps of the CO-to-H{sub 2} conversion factor (α{sub CO}) and dust-to-gas ratio (DGR) in 26 nearby, star-forming galaxies. We have simultaneously solved for α{sub CO} and the DGR by assuming that the DGR is approximately constant on kiloparsec scales. With this assumption, we can combine maps of dust mass surface density, CO-integrated intensity, and H I column density to solve for both α{sub CO} and the DGR with no assumptions about their value or dependence on metallicity or other parameters. Such a study has just become possible with the availability of high-resolution far-IR maps from the Herschel key program KINGFISH, {sup 12}CO J = (2-1) maps from the IRAM 30 m large program HERACLES, and H I 21 cm line maps from THINGS. We use a fixed ratio between the (2-1) and (1-0) lines to present our α{sub CO} results on the more typically used {sup 12}CO J = (1-0) scale and show using literature measurements that variations in the line ratio do not affect our results. In total, we derive 782 individual solutions for α{sub CO} and the DGR. On average, α{sub CO} = 3.1 M{sub ☉} pc{sup –2} (K km s{sup –1}){sup –1} for our sample with a standard deviation of 0.3 dex. Within galaxies, we observe a generally flat profile of α{sub CO} as a function of galactocentric radius. However, most galaxies exhibit a lower α{sub CO} value in the central kiloparsec—a factor of ∼2 below the galaxy mean, on average. In some cases, the central α{sub CO} value can be factors of 5-10 below the standard Milky Way (MW) value of α{sub CO,{sub MW}} = 4.4 M{sub ☉} pc{sup –2} (K km s{sup –1}){sup –1}. While for α{sub CO} we find only weak correlations with metallicity, the DGR is well-correlated with metallicity, with an approximately linear slope. Finally, we present several recommendations for choosing an appropriate α{sub CO} for studies of nearby galaxies.

  8. On the Relations among Regular, Equal Unique Variances, and Image Factor Analysis Models.

    ERIC Educational Resources Information Center

    Hayashi, Kentaro; Bentler, Peter M.

    2000-01-01

    Investigated the conditions under which the matrix of factor loadings from the factor analysis model with equal unique variances will give a good approximation to the matrix of factor loadings from the regular factor analysis model. Extends the results to the image factor analysis model. Discusses implications for practice. (SLD)

  9. Memory systems, processes, and tasks: taxonomic clarification via factor analysis.

    PubMed

    Bruss, Peter J; Mitchell, David B

    2009-01-01

    The nature of various memory systems was examined using factor analysis. We reanalyzed data from 11 memory tasks previously reported in Mitchell and Bruss (2003). Four well-defined factors emerged, closely resembling episodic and semantic memory and conceptual and perceptual implicit memory, in line with both memory systems and transfer-appropriate processing accounts. To explore taxonomic issues, we ran separate analyses on the implicit tasks. Using a cross-format manipulation (pictures vs. words), we identified 3 prototypical tasks. Word fragment completion and picture fragment identification tasks were "factor pure," tapping perceptual processes uniquely. Category exemplar generation revealed its conceptual nature, yielding both cross-format priming and a picture superiority effect. In contrast, word stem completion and picture naming were more complex, revealing attributes of both processes. PMID:19507425

  10. SEPARABLE FACTOR ANALYSIS WITH APPLICATIONS TO MORTALITY DATA

    PubMed Central

    Fosdick, Bailey K.; Hoff, Peter D.

    2014-01-01

    Human mortality data sets can be expressed as multiway data arrays, the dimensions of which correspond to categories by which mortality rates are reported, such as age, sex, country and year. Regression models for such data typically assume an independent error distribution or an error model that allows for dependence along at most one or two dimensions of the data array. However, failing to account for other dependencies can lead to inefficient estimates of regression parameters, inaccurate standard errors and poor predictions. An alternative to assuming independent errors is to allow for dependence along each dimension of the array using a separable covariance model. However, the number of parameters in this model increases rapidly with the dimensions of the array and, for many arrays, maximum likelihood estimates of the covariance parameters do not exist. In this paper, we propose a submodel of the separable covariance model that estimates the covariance matrix for each dimension as having factor analytic structure. This model can be viewed as an extension of factor analysis to array-valued data, as it uses a factor model to estimate the covariance along each dimension of the array. We discuss properties of this model as they relate to ordinary factor analysis, describe maximum likelihood and Bayesian estimation methods, and provide a likelihood ratio testing procedure for selecting the factor model ranks. We apply this methodology to the analysis of data from the Human Mortality Database, and show in a cross-validation experiment how it outperforms simpler methods. Additionally, we use this model to impute mortality rates for countries that have no mortality data for several years. Unlike other approaches, our methodology is able to estimate similarities between the mortality rates of countries, time periods and sexes, and use this information to assist with the imputations. PMID:25489353

  11. Human Modeling for Ground Processing Human Factors Engineering Analysis

    NASA Technical Reports Server (NTRS)

    Stambolian, Damon B.; Lawrence, Brad A.; Stelges, Katrine S.; Steady, Marie-Jeanne O.; Ridgwell, Lora C.; Mills, Robert E.; Henderson, Gena; Tran, Donald; Barth, Tim

    2011-01-01

    There have been many advancements and accomplishments over the last few years using human modeling for human factors engineering analysis for design of spacecraft. The key methods used for this are motion capture and computer generated human models. The focus of this paper is to explain the human modeling currently used at Kennedy Space Center (KSC), and to explain the future plans for human modeling for future spacecraft designs

  12. Method for factor analysis of GC/MS data

    DOEpatents

    Van Benthem, Mark H; Kotula, Paul G; Keenan, Michael R

    2012-09-11

    The method of the present invention provides a fast, robust, and automated multivariate statistical analysis of gas chromatography/mass spectroscopy (GC/MS) data sets. The method can involve systematic elimination of undesired, saturated peak masses to yield data that follow a linear, additive model. The cleaned data can then be subjected to a combination of PCA and orthogonal factor rotation followed by refinement with MCR-ALS to yield highly interpretable results.

  13. Human Modeling For Ground Processing Human Factors Engineering Analysis

    NASA Technical Reports Server (NTRS)

    Tran, Donald; Stambolian, Damon; Henderson, Gena; Barth, Tim

    2011-01-01

    There have been many advancements and accomplishments over that last few years using human modeling for human factors engineering analysis for design of spacecraft and launch vehicles. The key methods used for this are motion capture and computer generated human models. The focus of this paper is to explain the different types of human modeling used currently and in the past at Kennedy Space Center (KSC) currently, and to explain the future plans for human modeling for future spacecraft designs.

  14. Space Human Factors Engineering Gap Analysis Project Final Report

    NASA Technical Reports Server (NTRS)

    Hudy, Cynthia; Woolford, Barbara

    2006-01-01

    Humans perform critical functions throughout each phase of every space mission, beginning with the mission concept and continuing to post-mission analysis (Life Sciences Division, 1996). Space missions present humans with many challenges - the microgravity environment, relative isolation, and inherent dangers of the mission all present unique issues. As mission duration and distance from Earth increases, in-flight crew autonomy will increase along with increased complexity. As efforts for exploring the moon and Mars advance, there is a need for space human factors research and technology development to play a significant role in both on-orbit human-system interaction, as well as the development of mission requirements and needs before and after the mission. As part of the Space Human Factors Engineering (SHFE) Project within the Human Research Program (HRP), a six-month Gap Analysis Project (GAP) was funded to identify any human factors research gaps or knowledge needs. The overall aim of the project was to review the current state of human factors topic areas and requirements to determine what data, processes, or tools are needed to aid in the planning and development of future exploration missions, and also to prioritize proposals for future research and technology development.

  15. Emergency conversion in off-pump coronary artery bypass grafting.

    PubMed

    Tabata, Minoru; Takanashi, Shuichiro; Horai, Tetsuya; Fukui, Toshihiro; Hosoda, Yasuyuki

    2006-10-01

    Emergency conversion to cardiopulmonary bypass in off-pump coronary artery bypass grafting is recognized to increase operative mortality and morbidity. We conducted a retrospective review of 616 consecutive patients who were planned for off-pump coronary artery bypass grafting from April 2001 to July 2004. Fourteen patients (2.3%) required emergency conversion to cardiopulmonary bypass. Operative mortality was 13.3% in the conversion group and 1.2% in the non-conversion group (P<0.001). The incidence of reoperation for bleeding was 7.1% and 1.0%, respectively (P=0.032) and that of respiratory failure was 35.7% and 3.3%, respectively (P<0.001). Multivariable analysis showed that mitral regurgitation and chronic obstructive pulmonary disease were predictors of emergency conversion with all causes except for bleeding, and that mitral regurgitation and no use of a heart positioning device were predictors of emergency conversion due to hemodynamic compromise during distal anastomosis of the circumflex artery territory. In conclusion, emergency conversion in off-pump coronary artery bypass grafting increases operative mortality and morbidity. Mitral regurgitation and chronic obstructive pulmonary disease are risk factors for emergency conversion. Use of a heart positioning device decreases hemodynamic compromise during anastomosis of the circumflex artery territory. PMID:17670644

  16. µ-Calpain Conversion of Antiapoptotic Bfl-1 (BCL2A1) into a Prodeath Factor Reveals Two Distinct alpha-Helices Inducing Mitochondria-Mediated Apoptosis

    PubMed Central

    Jugé, Romain; Debaud, Anne-Laure; Giménez, Diana; Gillet, Germain; Bonnefoy-Bérard, Nathalie; Salgado, Jesús; Salles, Gilles; Aouacheria, Abdel; Kucharczak, Jérôme

    2012-01-01

    Anti-apoptotic Bfl-1 and pro-apoptotic Bax, two members of the Bcl-2 family sharing a similar structural fold, are classically viewed as antagonist regulators of apoptosis. However, both proteins were reported to be death inducers following cleavage by the cysteine protease µ-calpain. Here we demonstrate that calpain-mediated cleavage of full-length Bfl-1 induces the release of C-terminal membrane active α-helices that are responsible for its conversion into a pro-apoptotic factor. A careful comparison of the different membrane-active regions present in the Bfl-1 truncated fragments with homologous domains of Bax show that helix α5, but not α6, of Bfl-1 induces cell death and cytochrome c release from purified mitochondria through a Bax/Bak-dependent mechanism. In contrast, both helices α5 and α6 of Bax permeabilize mitochondria regardless of the presence of Bax or Bak. Moreover, we provide evidence that the α9 helix of Bfl-1 promotes cytochrome c release and apoptosis through a unique membrane-destabilizing action whereas Bax-α9 does not display such activities. Hence, despite a common 3D-structure, C-terminal toxic domains present on Bfl-1 and Bax function in a dissimilar manner to permeabilize mitochondria and induce apoptosis. These findings provide insights for designing therapeutic approaches that could exploit the cleavage of endogenous Bcl-2 family proteins or the use of Bfl-1/Bax-derived peptides to promote tumor cell clearance. PMID:22745672

  17. Converse Piezoelectricity

    NASA Astrophysics Data System (ADS)

    Springborg, Michael; Kirtman, Bernard

    2013-03-01

    Piezoelectricity results from a coupling between responses to mechanical and electric perturbations and leads to changes in the polarization due to strain or stress or, alternatively, the occurrence of strain as a function of an applied external, electrostatic field (i.e., converse piezoelectricity). Theoretical studies of those properties for extended systems require accordingly that their dipole moment or polarization can be calculated. However, whereas the definition of the operator for the dipole moment for any finite system is trivial, it is only within the last 2 decades that the expressions for the equivalent operator in the independent-particle approximation for the infinite and periodic system have been presented. Here, we demonstrate that the so called branch dependence of the polarization for the infinite, periodic system is related to physical observables in contrast to what often is assumed. This is related to the finding that converse piezoelectric properties depend both on the surfaces of the samples of interest even for samples with size well above the thermodynamic limit. However, we shall demonstrate that these properties can be calculated without explicitly taking the surfaces into account. Both the foundations and results for real system shall be presented.

  18. Multivariate analysis of pathophysiological factors in reflux oesophagitis.

    PubMed Central

    Cadiot, G; Bruhat, A; Rigaud, D; Coste, T; Vuagnat, A; Benyedder, Y; Vallot, T; Le Guludec, D; Mignon, M

    1997-01-01

    BACKGROUND: Reflux oesophagitis is considered a multifactorial disease, but the respective roles of the main factors involved in its pathophysiology have not been clearly established. AIMS: To attempt to assign these roles by means of a multivariate logistic regression analysis of the main parameters associated with reflux oesophagitis. PATIENTS: Eighty seven patients with gastro-oesophageal reflux disease were studied: 41 without oesophagitis and 46 with reflux oesophagitis grade 1 to 3. METHODS: (1) Monovariate comparison of patients' characteristics and of parameters derived from in hospital 24 hour oesophageal pH monitoring, oesophageal manometry, double isotope gastric emptying studies, and basal and pentagastrin stimulated gastric acid and pepsin output determinations, between patients with and without oesophagitis. (2) Multivariate logistic regression analysis including the parameters significant in the monovariate analysis. RESULTS: Among the 16 significant parameters from monovariate analysis, three significant independent parameters were identified by multivariate logistic regression analysis: number of refluxes lasting more than five minutes, reflecting oesophageal acid clearance (p = 0.002); basal lower oesophageal sphincter pressure (p = 0.008); and peak acid output (p = 0.012). These three parameters were not correlated with each other. The multivariate model was highly discriminant (correct classification of 81.3% of the cases (95% confidence intervals 0.723, 0.903). Risk for oesophagitis increased as a function of the tercile threshold values of the three parameters. Odds ratios of the three parameters for oesophagitis risk were similar, regardless of whether they were calculated when the patients were compared as a function of oesophagitis grade or the presence or absence of oesophagitis. CONCLUSIONS: This multivariate approach adds evidence that impaired oesophageal acid clearance and hypotonic lower oesophageal sphincter are the two major

  19. A Bayes factor meta-analysis of Bem's ESP claim.

    PubMed

    Rouder, Jeffrey N; Morey, Richard D

    2011-08-01

    In recent years, statisticians and psychologists have provided the critique that p-values do not capture the evidence afforded by data and are, consequently, ill suited for analysis in scientific endeavors. The issue is particular salient in the assessment of the recent evidence provided for ESP by Bem (2011) in the mainstream Journal of Personality and Social Psychology. Wagenmakers, Wetzels, Borsboom, and van der Maas (Journal of Personality and Social Psychology, 100, 426-432, 2011) have provided an alternative Bayes factor assessment of Bem's data, but their assessment was limited to examining each experiment in isolation. We show here that the variant of the Bayes factor employed by Wagenmakers et al. is inappropriate for making assessments across multiple experiments, and cannot be used to gain an accurate assessment of the total evidence in Bem's data. We develop a meta-analytic Bayes factor that describes how researchers should update their prior beliefs about the odds of hypotheses in light of data across several experiments. We find that the evidence that people can feel the future with neutral and erotic stimuli to be slight, with Bayes factors of 3.23 and 1.57, respectively. There is some evidence, however, for the hypothesis that people can feel the future with emotionally valenced nonerotic stimuli, with a Bayes factor of about 40. Although this value is certainly noteworthy, we believe it is orders of magnitude lower than what is required to overcome appropriate skepticism of ESP. PMID:21573926

  20. Generalized five-dimensional dynamic and spectral factor analysis

    SciTech Connect

    El Fakhri, Georges; Sitek, Arkadiusz; Zimmerman, Robert E.; Ouyang Jinsong

    2006-04-15

    We have generalized the spectral factor analysis and the factor analysis of dynamic sequences (FADS) in SPECT imaging to a five-dimensional general factor analysis model (5D-GFA), where the five dimensions are the three spatial dimensions, photon energy, and time. The generalized model yields a significant advantage in terms of the ratio of the number of equations to that of unknowns in the factor analysis problem in dynamic SPECT studies. We solved the 5D model using a least-squares approach. In addition to the traditional non-negativity constraints, we constrained the solution using a priori knowledge of both time and energy, assuming that primary factors (spectra) are Gaussian-shaped with full-width at half-maximum equal to gamma camera energy resolution. 5D-GFA was validated in a simultaneous pre-/post-synaptic dual isotope dynamic phantom study where {sup 99m}Tc and {sup 123}I activities were used to model early Parkinson disease studies. 5D-GFA was also applied to simultaneous perfusion/dopamine transporter (DAT) dynamic SPECT in rhesus monkeys. In the striatal phantom, 5D-GFA yielded significantly more accurate and precise estimates of both primary {sup 99m}Tc (bias=6.4%{+-}4.3%) and {sup 123}I (-1.7%{+-}6.9%) time activity curves (TAC) compared to conventional FADS (biases=15.5%{+-}10.6% in {sup 99m}Tc and 8.3%{+-}12.7% in {sup 123}I, p<0.05). Our technique was also validated in two primate dynamic dual isotope perfusion/DAT transporter studies. Biases of {sup 99m}Tc-HMPAO and {sup 123}I-DAT activity estimates with respect to estimates obtained in the presence of only one radionuclide (sequential imaging) were significantly lower with 5D-GFA (9.4%{+-}4.3% for {sup 99m}Tc-HMPAO and 8.7%{+-}4.1% for {sup 123}I-DAT) compared to biases greater than 15% for volumes of interest (VOI) over the reconstructed volumes (p<0.05). 5D-GFA is a novel and promising approach in dynamic SPECT imaging that can also be used in other modalities. It allows accurate and precise

  1. Serial QuantiFERON-TB Gold In-Tube assay and tuberculin skin test to diagnose latent tuberculosis in household Mexican contacts: conversion and reversion rates and associated factors using conventional and borderline zone definitions

    PubMed Central

    Monárrez-Espino, Joel; Enciso-Moreno, José Antonio; Laflamme, Lucie; Serrano, Carmen J

    2014-01-01

    A cohort of 123 adult contacts was followed for 18‐24 months (86 completed the follow-up) to compare conversion and reversion rates based on two serial measures of QuantiFERON (QFT) and tuberculin skin test (TST) (PPD from TUBERSOL, Aventis Pasteur, Canada) for diagnosing latent tuberculosis (TB) in household contacts of TB patients using conventional (C) and borderline zone (BZ) definitions. Questionnaires were used to obtain information regarding TB exposure, TB risk factors and socio-demographic data. QFT (IU/mL) conversion was defined as <0.35 to ≥0.35 (C) or <0.35 to >0.70 (BZ) and reversion was defined as ≥0.35 to <0.35 (C) or ≥0.35 to <0.20 (BZ); TST (mm) conversion was defined as <5 to ≥5 (C) or <5 to >10 (BZ) and reversion was defined as ≥5 to <5 (C). The QFT conversion and reversion rates were 10.5% and 7% with C and 8.1% and 4.7% with the BZ definitions, respectively. The TST rates were higher compared with QFT, especially with the C definitions (conversion 23.3%, reversion 9.3%). The QFT conversion and reversion rates were higher for TST ≥5; for TST, both rates were lower for QFT <0.35. No risk factors were associated with the probability of converting or reverting. The inconsistency and apparent randomness of serial testing is confusing and adds to the limitations of these tests and definitions to follow-up close TB contacts. PMID:25410989

  2. Serial QuantiFERON-TB Gold In-Tube assay and tuberculin skin test to diagnose latent tuberculosis in household Mexican contacts: conversion and reversion rates and associated factors using conventional and borderline zone definitions.

    PubMed

    Monárrez-Espino, Joel; Enciso-Moreno, José Antonio; Laflamme, Lucie; Serrano, Carmen J

    2014-11-01

    A cohort of 123 adult contacts was followed for 18-24 months (86 completed the follow-up) to compare conversion and reversion rates based on two serial measures of QuantiFERON (QFT) and tuberculin skin test (TST) (PPD from TUBERSOL, Aventis Pasteur, Canada) for diagnosing latent tuberculosis (TB) in household contacts of TB patients using conventional (C) and borderline zone (BZ) definitions. Questionnaires were used to obtain information regarding TB exposure, TB risk factors and socio-demographic data. QFT (IU/mL) conversion was defined as <0.35 to ≥0.35 (C) or <0.35 to >0.70 (BZ) and reversion was defined as ≥0.35 to <0.35 (C) or ≥0.35 to <0.20 (BZ); TST (mm) conversion was defined as <5 to ≥5 (C) or <5 to >10 (BZ) and reversion was defined as ≥5 to <5 (C). The QFT conversion and reversion rates were 10.5% and 7% with C and 8.1% and 4.7% with the BZ definitions, respectively. The TST rates were higher compared with QFT, especially with the C definitions (conversion 23.3%, reversion 9.3%). The QFT conversion and reversion rates were higher for TST ≥5; for TST, both rates were lower for QFT <0.35. No risk factors were associated with the probability of converting or reverting. The inconsistency and apparent randomness of serial testing is confusing and adds to the limitations of these tests and definitions to follow-up close TB contacts. PMID:25410989

  3. Human factors review for Severe Accident Sequence Analysis (SASA)

    SciTech Connect

    Krois, P.A.; Haas, P.M.; Manning, J.J.; Bovell, C.R.

    1984-01-01

    The paper will discuss work being conducted during this human factors review including: (1) support of the Severe Accident Sequence Analysis (SASA) Program based on an assessment of operator actions, and (2) development of a descriptive model of operator severe accident management. Research by SASA analysts on the Browns Ferry Unit One (BF1) anticipated transient without scram (ATWS) was supported through a concurrent assessment of operator performance to demonstrate contributions to SASA analyses from human factors data and methods. A descriptive model was developed called the Function Oriented Accident Management (FOAM) model, which serves as a structure for bridging human factors, operations, and engineering expertise and which is useful for identifying needs/deficiencies in the area of accident management. The assessment of human factors issues related to ATWS required extensive coordination with SASA analysts. The analysis was consolidated primarily to six operator actions identified in the Emergency Procedure Guidelines (EPGs) as being the most critical to the accident sequence. These actions were assessed through simulator exercises, qualitative reviews, and quantitative human reliability analyses. The FOAM descriptive model assumes as a starting point that multiple operator/system failures exceed the scope of procedures and necessitates a knowledge-based emergency response by the operators. The FOAM model provides a functionally-oriented structure for assembling human factors, operations, and engineering data and expertise into operator guidance for unconventional emergency responses to mitigate severe accident progression and avoid/minimize core degradation. Operators must also respond to potential radiological release beyond plant protective barriers. Research needs in accident management and potential uses of the FOAM model are described. 11 references, 1 figure.

  4. Characterization and Risk Factor Analysis for Reoperation After Microendoscopic Diskectomy.

    PubMed

    Hong, Xin; Liu, Lei; Bao, Junping; Shi, Rui; Fan, Yudong; Wu, Xiaotao

    2015-06-01

    A population-based database of 1263 consecutive patients who underwent microendoscopic diskectomy for single-level lumbar disk herniation between 2005 and 2010 was retrospectively analyzed to identify causes and characteristics of reoperation and associated risk factors. A total of 952 patients were eligible. Of these, 58 had revision spinal surgery. Causes and clinical parameters were retrospectively assessed, and possible risk factors were evaluated by multivariate logistic regression analysis. In total, 76 disk herniations were excised with revision diskectomy, with or without interbody fusion. The overall mean interval between primary surgery and revision surgery was 39.05 months (range, 2-95 months). Cumulative overall reoperation rates gradually increased from 1.56% at 1 year to 8.17% after nearly 10 years. Reoperated patients were older and had a higher level of lumbar degeneration, with severe Modic changes (type 1, 17.2%; type 2, 34.5%), vs patients without reoperation (type 1, 1.5%; type 2, 30.6%). In addition, patients with reoperation had a higher rate of obvious adjacent disk degeneration (81.1%). Logistic regression analysis showed that adjacent segment degeneration and Pfirrmann grading for disk degeneration were significant risk factors for reoperation after primary microendoscopic diskectomy (odds ratios, 2.448 and 1.510, respectively). The current study reported a relatively low incidence of reoperation after primary microendoscopic diskectomy. Adjacent segment degeneration and Pfirrmann grading for disk degeneration were identified as risk factors for reoperation after microendoscopic diskectomy to treat lumbar disk herniation. Treatment options for patients with these factors at the first visit should be carefully evaluated. PMID:26091222

  5. Quantitative Analysis of Defects in Silicon. [to predict energy conversion efficiency of silicon samples for solar cells

    NASA Technical Reports Server (NTRS)

    Natesh, R.; Smith, J. M.; Qidwai, H. A.; Bruce, T.

    1979-01-01

    The evaluation and prediction of the conversion efficiency for a variety of silicon samples with differences in structural defects, such as grain boundaries, twin boundaries, precipitate particles, dislocations, etc. are discussed. Quantitative characterization of these structural defects, which were revealed by etching the surface of silicon samples, is performed by using an image analyzer. Due to different crystal growth and fabrication techniques the various types of silicon contain a variety of trace impurity elements and structural defects. The two most important criteria in evaluating the various silicon types for solar cell applications are cost and conversion efficiency.

  6. Energy conversion

    SciTech Connect

    Woodall, J.M.

    1982-02-16

    Energy conversion capable of receiving input energy in thermal or radiant form at a variable rate and releasing energy in thermal, radiant or electrical form independent of rate is accomplished by providing a buffer member of a material that has three criteria: a melting temperature above 1300/sup degree/ K, a thermal conductance greater than 0.1 in calories per square centimeter per centimeter per degree per second and a latent heat of fusion of the order of 1 kilocalorie per mole. The converter can absorb energy of multiple types, store it and then release it in a form compatible with the prospective use. Sunlight of daylight duration and varying intensity is converted to steady 24 hour a day electrical output.

  7. Factor Analysis of the Modified Sexual Adjustment Questionnaire-Male

    PubMed Central

    Wilmoth, Margaret C.; Hanlon, Alexandra L.; Ng, Lit Soo; Bruner, Debra W.

    2015-01-01

    Background and Purpose The Sexual Adjustment Questionnaire (SAQ) is used in National Cancer Institute–sponsored clinical trials as an outcome measure for sexual functioning. The tool was revised to meet the needs for a clinically useful, theory-based outcome measure for use in both research and clinical settings. This report describes the modifications and validity testing of the modified Sexual Adjustment Questionnaire-Male (mSAQ-Male). Methods This secondary analysis of data from a large Radiation Therapy Oncology Group trial employed principal axis factor analytic techniques in estimating validity of the revised tool. The sample size was 686; most subjects were White, older than the age 60 years, and with a high school education and a Karnofsky performance scale (KPS) score of greater than 90. Results A 16-item, 3-factor solution resulted from the factor analysis. The mSAQ-Male was also found to be sensitive to changes in physical sexual functioning as measured by the KPS. Conclusion The mSAQ-Male is a valid self-report measure of sexuality that can be used clinically to detect changes in male sexual functioning. PMID:25255676

  8. Inference algorithms and learning theory for Bayesian sparse factor analysis

    NASA Astrophysics Data System (ADS)

    Rattray, Magnus; Stegle, Oliver; Sharp, Kevin; Winn, John

    2009-12-01

    Bayesian sparse factor analysis has many applications; for example, it has been applied to the problem of inferring a sparse regulatory network from gene expression data. We describe a number of inference algorithms for Bayesian sparse factor analysis using a slab and spike mixture prior. These include well-established Markov chain Monte Carlo (MCMC) and variational Bayes (VB) algorithms as well as a novel hybrid of VB and Expectation Propagation (EP). For the case of a single latent factor we derive a theory for learning performance using the replica method. We compare the MCMC and VB/EP algorithm results with simulated data to the theoretical prediction. The results for MCMC agree closely with the theory as expected. Results for VB/EP are slightly sub-optimal but show that the new algorithm is effective for sparse inference. In large-scale problems MCMC is infeasible due to computational limitations and the VB/EP algorithm then provides a very useful computationally efficient alternative.

  9. Contextual Risk Factors for Low Birth Weight: A Multilevel Analysis

    PubMed Central

    Kayode, Gbenga A.; Amoakoh-Coleman, Mary; Agyepong, Irene Akua; Ansah, Evelyn; Grobbee, Diederick E.; Klipstein-Grobusch, Kerstin

    2014-01-01

    Background Low birth weight (LBW) remains to be a leading cause of neonatal death and a major contributor to infant and under-five mortality. Its prevalence has not declined in the last decade in sub-Saharan Africa (SSA) and Asia. Some individual level factors have been identified as risk factors for LBW but knowledge is limited on contextual risk factors for LBW especially in SSA. Methods Contextual risk factors for LBW in Ghana were identified by performing multivariable multilevel logistic regression analysis of 6,900 mothers dwelling in 412 communities that participated in the 2003 and 2008 Demographic and Health Surveys in Ghana. Results Contextual-level factors were significantly associated with LBW: Being a rural dweller increased the likelihood of having a LBW infant by 43% (OR 1.43; 95% CI 1.01–2.01; P-value <0.05) while living in poverty-concentrated communities increased the risk of having a LBW infant twofold (OR 2.16; 95% CI 1.29–3.61; P-value <0.01). In neighbourhoods with a high coverage of safe water supply the odds of having a LBW infant reduced by 28% (OR 0.74; 95% CI 0.57–0.96; P-value <0.05). Conclusion This study showed contextual risk factors to have independent effects on the prevalence of LBW infants. Being a rural dweller, living in a community with a high concentration of poverty and a low coverage of safe water supply were found to increase the prevalence of LBW infants. Implementing appropriate community-based intervention programmes will likely reduce the occurrence of LBW infants. PMID:25360709

  10. The Use of Exploratory Factor Analysis and Principal Components Analysis in Communication Research.

    ERIC Educational Resources Information Center

    Park, Hee Sun; Dailey, Rene; Lemus, Daisy

    2002-01-01

    Discusses the distinct purposes of principal components analysis (PCA) and exploratory factor analysis (EFA), using two data sets as examples. Reviews the use of each technique in three major communication journals: "Communication Monographs,""Human Communication Research," and "Communication Research." Finds that the use of EFA and PCA indicates…

  11. Analysis of Social Cohesion in Health Data by Factor Analysis Method: The Ghanaian Perspective

    ERIC Educational Resources Information Center

    Saeed, Bashiru I. I.; Xicang, Zhao; Musah, A. A. I.; Abdul-Aziz, A. R.; Yawson, Alfred; Karim, Azumah

    2013-01-01

    We investigated the study of the overall social cohesion of Ghanaians. In this study, we considered the paramount interest of the involvement of Ghanaians in their communities, their views of other people and institutions, and their level of interest in both local and national politics. The factor analysis method was employed for analysis using R…

  12. Using Conversation Analysis To Evaluate Pre-Sequences in Invitation, Offer, and Request Dialogues in ESL Textbooks.

    ERIC Educational Resources Information Center

    Bernsten, Suzanne Graham

    This paper uses conversation analytic research on a particular practice of organization in talk--pre-sequences--to evaluate English as a Second Language (ESL) textbook dialogues and make recommendations for their improvement. Pre-sequences, such as pre-invitations (e.g., What are you doing on Friday night?) and their responses are used to show…

  13. What Do You Mean We Preacher?: A Gricean Analysis of First-Person Pronoun Use in Conversational Preaching

    ERIC Educational Resources Information Center

    Jackson, Micah T. J.

    2012-01-01

    Throughout history, preachers have used various models to understand the relationship between the preacher and the hearers of sermons. In recent years, homileticians have responded to the challenges of postmodernism by exploring the metaphor of conversation as a way to develop less hierarchical or authoritarian conceptions of role and authority.…

  14. A Content Analysis of Themes That Emerge from School Principals' Web2.0 Conversations

    ERIC Educational Resources Information Center

    Manning, Rory

    2011-01-01

    The purpose of this qualitative study was to analyze the self initiated conversations held by school principals on web2.o platforms, such as blogs, through the lens of current leadership standards. The online writings of thirteen school principals were analyzed using grounded theory techniques (Strauss and Corbin, 1998) to elucidate emerging…

  15. [Risk Factor Analysis of Pneumonia after Cardiovascular Surgery].

    PubMed

    Maekawa, Yoshiyuki; Abe, Shuichi; Nakamura, Ken; Uchida, Tetsuro; Sadahiro, Mitsuaki; Morikane, Keita

    2016-08-01

    Pneumonia is a major and life-threatening complication after cardiovascular surgery. The objective of our study was to describe epidemiology, clinical characteristics, and risk factors of pneumonia after cardiovascular surgery. From January 2007 to December 2011, 511 consecutive patients (age 67.3±11.9;336 men, 175 women) were enrolled in this study. Pneumonia was diagnosed according to Centers of Disease Control and Prevention surveillance criteria for healthcare associated infection. Data collection included preoperative, intraoperative, and post-operative variables. The overall incidence of pneumonia was 72 cases(14.0%). The mortality in pneumonia group was significantly higher than that in non-pneumonia group (16.6% vs 4.3%, Odds ratio 4.4 p<0.001). Multi-logistic analysis revealed that elderly patient, preoperative congestive heart failure, preoperative hemodialysis, and operation of the thoracic aorta were independent risk factors for pneumonia after cardiovascular surgery. PMID:27476560

  16. Risk factors for rape re-victimisation: a retrospective analysis.

    PubMed

    Lurie, S; Boaz, M; Golan, A

    2013-11-01

    Sexual re-victimisation refers to a pattern in which the sexual assault victim has an increased risk of subsequent victimisation relative to an individual who was never victimised. The purpose of our study was to identify risks factors for a second rape, the severest form of sexual re-victimisation. All rape victims treated at the First Regional Israeli Center for Sexual Assault Victims between October 2000 and July 2010 were included in this retrospective analysis. We compared characteristics of 53 rape victims who were victimised twice to those of 1,939 rape victims who were victimised once. We identified several risk factors for a second rape, which can be used in prevention programmes. These are: psychiatric background, history of social services involvement, adulthood, non-virginity and minority ethnicity. PMID:24219731

  17. Confirmatory factor analysis of the revised Personal Style Inventory.

    PubMed

    Bagby, R M; Parker, J D; Joffe, R T; Schuller, D; Gilchrist, E

    1998-03-01

    The revised Personal Style Inventory (PSI) was developed to measure the sociotropy and autonomy personality dimensions; both of these dimensions are thought to confer specific vulnerabilities to the onset, maintenance, and reoccurrence of depression. Confirmatory factor analysis was used to test the theoretical structure that informed the construction of the PSI. Using a large sample of nonclinical participants (n = 869) and a sample of outpatients with major depression (n = 101), both the items and the subscales of the PSI decomposed into factor structures that were, overall, fair to good representations of the theoretical model. Modifications were needed at the subscale level to achieve an adequate fit for the nonclinical and clinical samples, which provide implications for both the measurement and theory of the PSI and the sociotropy and autonomy domains. PMID:9458340

  18. How protective are respirator assigned protection factors: an uncertainty analysis.

    PubMed

    Nelson, T J; Jayjock, M A; Colton, C E

    2000-01-01

    This investigation evaluated the risk of overexposure for a selected assigned protection factor by performing Monte Carlo simulations. A model was constructed to assess respirator performance by calculating the concentration inside the respirator. Estimates of the factors that affect respirator performance were described as distributions. The distributions used a worst case estimate for concentration in the workplace, the worst case for respirator performance (the fifth percentile person), and the worst case for exhalation valve leakage. A Monte Carlo analysis then provided estimates of the percentage of time that concentration inside the respirator exceeded the occupational exposure limit (OEL). For a half-facepiece respirator with an APF of 10, the calculations indicated a low risk of being exposed above an OEL, with mean exposures being controlled well below an OEL. PMID:10885889

  19. Catalyst increases COS conversion

    SciTech Connect

    Goodboy, K.P.

    1985-02-18

    Increasingly stringent air quality legislation is placing greater emphasis on conversion of COS and CS/sub 2/ in Claus plants for the maximum sulfur recovery. Overall sulfur recovery goals are dependent upon outstanding service from the Claus catalyst in each reactor because catalyst activity is a major factor influencing plant performance. Today's catalyst are much improved over those used 10 years ago for the Claus (H/sub 2/S/SO/sub 2/) reaction. Recent technical efforts have focused on the conversion of COS and CS/sub 2/. These carbon-sulfur compounds can account for as much as 50% of the sulfur going to the incinerator, which essentially converts all remaining sulfur species to SO/sub 2/ for atmospheric dispersion. Previously, the mechanism of Claus COS conversion, i.e., hydrolysis or oxidation by SO/sub 2/, was studied and the conclusion was that oxidation by SO/sub 2/ appears to be the predominate mode of COS conversion on sulfated alumina catalysts.

  20. Physics Metacognition Inventory Part II: Confirmatory factor analysis and Rasch analysis

    NASA Astrophysics Data System (ADS)

    Taasoobshirazi, Gita; Bailey, MarLynn; Farley, John

    2015-11-01

    The Physics Metacognition Inventory was developed to measure physics students' metacognition for problem solving. In one of our earlier studies, an exploratory factor analysis provided evidence of preliminary construct validity, revealing six components of students' metacognition when solving physics problems including knowledge of cognition, planning, monitoring, evaluation, debugging, and information management. The college students' scores on the inventory were found to be reliable and related to students' physics motivation and physics grade. However, the results of the exploratory factor analysis indicated that the questionnaire could be revised to improve its construct validity. The goal of this study was to revise the questionnaire and establish its construct validity through a confirmatory factor analysis. In addition, a Rasch analysis was applied to the data to better understand the psychometric properties of the inventory and to further evaluate the construct validity. Results indicated that the final, revised inventory is a valid, reliable, and efficient tool for assessing student metacognition for physics problem solving.

  1. A Human Factors Analysis of EVA Time Requirements

    NASA Technical Reports Server (NTRS)

    Pate, Dennis W.

    1997-01-01

    Human Factors Engineering (HFE) is a discipline whose goal is to engineer a safer, more efficient interface between humans and machines. HFE makes use of a wide range of tools and techniques to fulfill this goal. One of these tools is known as motion and time study, a technique used to develop time standards for given tasks. During the summer of 1995, a human factors motion and time study was initiated with the goals of developing a database of EVA task times and developing a method of utilizing the database to predict how long an EVA should take. Initial development relied on the EVA activities performed during the STS-61 (Hubble) mission. The first step of the study was to become familiar with EVA's, the previous task-time studies, and documents produced on EVA's. After reviewing these documents, an initial set of task primitives and task-time modifiers was developed. Data was collected from videotaped footage of two entire STS-61 EVA missions and portions of several others, each with two EVA astronauts. Feedback from the analysis of the data was used to further refine the primitives and modifiers used. The project was continued during the summer of 1996, during which data on human errors was also collected and analyzed. Additional data from the STS-71 mission was also collected. Analysis of variance techniques for categorical data was used to determine which factors may affect the primitive times and how much of an effect they have. Probability distributions for the various task were also generated. Further analysis of the modifiers and interactions is planned.

  2. Pig feeding strategy coupled with effluent management - fresh or stored slurry, solid phase separation - on methane potential and methane conversion factors during storage

    NASA Astrophysics Data System (ADS)

    Jarret, Guillaume; Martinez, José; Dourmad, Jean-Yves

    2011-11-01

    In the guideline for the determination of methane (CH 4) emission from animal manure (IPCC) the amount of CH 4 emitted is generally calculated according to an equation combining the amount of organic matter (OM) or volatile solids excreted, the ultimate CH 4 potential ( B0) of excreta and a system-specific methane conversion factor (MCF, %) that reflects the portion of B0 that is really converted into CH 4. The objective of the present study was to investigate the effect of the modification of dietary crude protein and fibre levels on B0 of pig slurry and on subsequent MCF according to different strategies of slurry management. Five experimental diets differing mainly in their crude protein and fibre content were compared. Two types of measurement of CH 4 emission were performed. The first was the measurement of B0 of slurry using biomethanogene potential (BMP) test. The second consisted in a storage simulation, which was performed on different kinds of effluents: fresh slurry (FSl), stored slurry (SSl), and faeces mixed with water (FaW). The type of diet and the type of effluent affected ( P < 0.001) CH 4 production after 30, 50 and 100 days. Moreover, the interaction between type of effluent and type of diet was significant for CH 4 emission and for MCF. CH 4 production was the highest for BMP, the average production of CH 4 during storage from FaW, FSl and SSl samples representing 77%, 58% and 64% of the B0 value. The dynamic of CH 4 production during BMP tests was rather similar for all dietary treatments whereas it differed for storage simulation studies with significant effects of dietary CP and fibre contents. The results from this study indicate that the type of diet has a significant but rather limited effect on B0 value of effluent. The effect of diet is much more marked on MCF, with lower values for high protein diets, and higher values for high fibre diets. MCF is also affected by manure management, the values measured on separated faeces from urine

  3. ANALYSIS OF THE PERFORMANCE AND COST EFFECTIVENESS OF NINE SMALL WIND ENERGY CONVERSION SYSTEMS FUNDED BY THE DOE SMALL GRANTS PROGRAM

    SciTech Connect

    Kay, J.

    1982-04-01

    This report presents an analysis of the technical performance and cost effectiveness of nine small wind energy conversion systems (SWECS) funded during FY 1979 by the U.S. Department of Energy. Chapter 1 gives an analytic framework with which to evaluate the systems. Chapter 2 consists of a review of each of the nine projects, including project technical overviews, estimates of energy savings, and results of economic analysis. Chapter 3 summarizes technical, economic, and institutional barriers that are likely to inhibit widespread dissemination of SWECS technology.

  4. Determining the Number of Factors to Retain in an Exploratory Factor Analysis Using Comparison Data of Known Factorial Structure

    ERIC Educational Resources Information Center

    Ruscio, John; Roche, Brendan

    2012-01-01

    Exploratory factor analysis (EFA) is used routinely in the development and validation of assessment instruments. One of the most significant challenges when one is performing EFA is determining how many factors to retain. Parallel analysis (PA) is an effective stopping rule that compares the eigenvalues of randomly generated data with those for…

  5. Factor Structure of the Student-Teacher Relationship Scale for Norwegian School-Age Children Explored with Confirmatory Factor Analysis

    ERIC Educational Resources Information Center

    Drugli, May Britt; Hjemdal, Odin

    2013-01-01

    The validity of the Student-Teacher Relationship Scale (STRS) was examined in a national sample of 863 Norwegian schoolchildren in grades 1-7 (aged 6-13). The original factor structure of the STRS was tested by confirmatory factor analysis (CFA). The CFA results did not support the original three-factor structure of the STRS. Subsequent CFA of the…

  6. Comprehensive analysis of plant rapid alkalization factor (RALF) genes.

    PubMed

    Sharma, Arti; Hussain, Adil; Mun, Bong-Gyu; Imran, Qari Muhammad; Falak, Noreen; Lee, Sang-Uk; Kim, Jae Young; Hong, Jeum Kyu; Loake, Gary John; Ali, Asad; Yun, Byung-Wook

    2016-09-01

    Receptor mediated signal carriers play a critical role in the regulation of plant defense and development. Rapid alkalization factor (RALF) proteins potentially comprise important signaling components which may have a key role in plant biology. The RALF gene family contains large number of genes in several plant species, however, only a few RALF genes have been characterized to date. In this study, an extensive database search identified 39, 43, 34 and 18 RALF genes in Arabidopsis, rice, maize and soybean, respectively. These RALF genes were found to be highly conserved across the 4 plant species. A comprehensive analysis including the chromosomal location, gene structure, subcellular location, conserved motifs, protein structure, protein-ligand interaction and promoter analysis was performed. RALF genes from four plant species were divided into 7 groups based on phylogenetic analysis. In silico expression analysis of these genes, using microarray and EST data, revealed that these genes exhibit a variety of expression patterns. Furthermore, RALF genes showed distinct expression patterns of transcript accumulation in vivo following nitrosative and oxidative stresses in Arabidopsis. Predicted interaction between RALF and heme ligand also showed that RALF proteins may contribute towards transporting or scavenging oxygen moieties. This suggests a possible role for RALF genes during changes in cellular redox status. Collectively, our data provides a valuable resource to prime future research in the role of RALF genes in plant growth and development. PMID:27155375

  7. Modeling PCB dechlorination in aquatic sediments by principal component based factor analysis and positive matrix factorization

    NASA Astrophysics Data System (ADS)

    Christensen, E. R.; Bzdusek, P. A.

    2003-04-01

    Anaerobic PCB dechlorination in aquatic sediments is a naturally occurring process that reduces the dioxin-like PCB toxicity. The PCB biphenyl structure is kept intact but the number of substituted chlorine atoms is reduced, primarily from the para and meta positions. Flanked para and meta chlorine dechlorination, as in process H/H', appears to be more common in-situ than flanked and unflanked para, and meta dechlorination as in process Q. Aroclors that are susceptible to these reactions include 1242, 1248, 1254, and 1260. These dechlorination reactions have recently been modeled by a least squares method for Ashtabula River, Ohio, and Fox River, Wisconsin sediments. Prior to modeling the dechlorination reactions for an ecosystem it is desirable to generate overall PCB source functions. One method to determine source functions is to use loading matrices of a factor analytical model. We have developed such models based both on a principal component approach including nonnegative oblique rotations, and positive matrix factorization (PMF). While the principal component method first requires an eigenvalue analysis of a covariance matrix, the PMF method is based on a direct least squares analysis considering simultaneously the loading and score matrices. Loading matrices obtained from the PMF method are somewhat sensitive to the initial guess of source functions. Preliminary work indicates that a hybrid approach considering first principal components and then PMF may offer an optimum solution. The relationship of PMF to conventional chemical mass balance modeling with or without some prior knowledge of source functions is also discussed.

  8. Risk factors for temporomandibular disorder: Binary logistic regression analysis

    PubMed Central

    Magalhães, Bruno G.; de-Sousa, Stéphanie T.; de Mello, Victor V C.; da-Silva-Barbosa, André C.; de-Assis-Morais, Mariana P L.; Barbosa-Vasconcelos, Márcia M V.

    2014-01-01

    Objectives: To analyze the influence of socioeconomic and demographic factors (gender, economic class, age and marital status) on the occurrence of temporomandibular disorder. Study Design: One hundred individuals from urban areas in the city of Recife (Brazil) registered at Family Health Units was examined using Axis I of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD) which addresses myofascial pain and joint problems (disc displacement, arthralgia, osteoarthritis and oesteoarthrosis). The Brazilian Economic Classification Criteria (CCEB) was used for the collection of socioeconomic and demographic data. Then, it was categorized as Class A (high social class), Classes B/C (middle class) and Classes D/E (very poor social class). The results were analyzed using Pearson’s chi-square test for proportions, Fisher’s exact test, nonparametric Mann-Whitney test and Binary logistic regression analysis. Results: None of the participants belonged to Class A, 72% belonged to Classes B/C and 28% belonged to Classes D/E. The multivariate analysis revealed that participants from Classes D/E had a 4.35-fold greater chance of exhibiting myofascial pain and 11.3-fold greater chance of exhibiting joint problems. Conclusions: Poverty is a important condition to exhibit myofascial pain and joint problems. Key words:Temporomandibular joint disorders, risk factors, prevalence. PMID:24316706

  9. Analysis of apoptosis-related genes in patients with clinically isolated syndrome and their association with conversion to multiple sclerosis.

    PubMed

    Hagman, Sanna; Kolasa, Marcin; Basnyat, Pabitra; Helminen, Mika; Kähönen, Mika; Dastidar, Prasun; Lehtimäki, Terho; Elovaara, Irina

    2015-03-15

    To analyse whether the expression of apoptotic transcripts is associated with the conversion from clinically isolated syndrome (CIS) to multiple sclerosis (MS). Eleven candidate transcripts belonging to the death receptor pathway, BCL-2, the inflammasome complex and NF-ΚB family were studied in the nonconverting and converting CIS patients during the four-year follow-up period. Conversion to MS was associated with marked variability in the expression of proapoptotic genes that were linked to TGF-B1 gene levels. The predominant expression of proapoptotic genes in patients with CIS suggests an increased potential to undergo apoptosis with the goal of terminating immune responses and regulating immune system homeostasis. PMID:25773154

  10. Clinicopathological Analysis of Factors Related to Colorectal Tumor Perforation

    PubMed Central

    Medina-Arana, Vicente; Martínez-Riera, Antonio; Delgado-Plasencia, Luciano; Rodríguez-González, Diana; Bravo-Gutiérrez, Alberto; Álvarez-Argüelles, Hugo; Alarcó-Hernández, Antonio; Salido-Ruiz, Eduardo; Fernández-Peralta, Antonia M.; González-Aguilera, Juan J.

    2015-01-01

    Abstract Colorectal tumor perforation is a life-threatening complication of this disease. However, little is known about the anatomopathological factors or pathophysiologic mechanisms involved. Pathological and immunohistochemical analysis of factors related with tumoral neo-angiogenesis, which could influence tumor perforation are assessed in this study. A retrospective study of patients with perforated colon tumors (Group P) and T4a nonperforated (controls) was conducted between 2001 and 2010. Histological variables (differentiation, vascular invasion, and location) and immunohistochemical (CD31, Growth Endothelial Vascular Factor (VEGF) and p53) related with tumor angiogenesis were analyzed. Of 2189 patients, 100 (4.56%) met the inclusion criteria. Of these, 49 patients had nonperforated (2.23%) and 51 had perforated tumors (2.32%). The P group had lower number of right-sided tumors (7/51, 13.7%) compared with controls (13/49, 36.7%) (P = .01). The high-grade tumors (undifferentiated) represented only 3.9% of the perforated tumors; the remaining 96.1% were well differentiated (P = .01). No differences between groups in the frequency of TP53 mutation or VEGF and CD31 expression were found. In the P group, only 2 (3.9%) had vascular invasion (P = .01). Of the 12 tumors with vascular invasion, only 2 were perforated (16.6%). The median number of metastatic lymph-nodes in P Group was 0 versus 3 in controls (Z = −4.2; P < .01). Pathological analysis of variables that indirectly measure the presence of tumor angiogenesis (differentiation, vascular invasion, and the number of metastatic lymph nodes) shows a relationship between this and the perforation, location, and tumor differentiation. We could not directly validate our hypothesis, by immunohistochemistry of TP53, VEGF, and CD31, that perforated tumors exhibit less angiogenesis. PMID:25881846

  11. Precision Analysis of Trimble Rtx Surveying Technology with Xfill Function in the Context of Obtained Conversion Observations

    NASA Astrophysics Data System (ADS)

    Krzyżek, Robert

    2015-02-01

    As a result of traditional geodetic surveying we usually achieve observations which are then used for calculating rectangular coordinates onto a plane along with precision evaluation. In this article the surveying methods are presented in which the situation is different. Test measurements were carried out, consisting in the measurement of a fragment of detailed control network in RTK (Real Time Kinematic) and RTX (Real Time Extended) mode with xFill function. First, the rectangular coordinates onto a plane (through the transformation of data ellipsoidal) were obtained, on the basis of which the conversion observations were determined and they were compared with each other, as well as with reference parameters - conversion observations out of detailed control network adjustment with use of the method of least squares. The results of the study allow to verify the precision and application possibilities of conversion observations obtained thanks to Trimble RTX technology with xFill function. Application of this surveying method in typical geodetic tasks is fully justifiable. Nevertheless, it is recommendable to be aware of the correlations of absolute or relative values obtained in RTX procedure to reference parameters, which in turn will enable conclusive verification of the possibilities of Trimble RTX technology application in certain geodetic surveys.

  12. A theoretical analysis of the current-voltage characteristics of solar cells. [and their energy conversion efficiency

    NASA Technical Reports Server (NTRS)

    Dunbar, P. M.; Hauser, J. R.

    1976-01-01

    Various mechanisms which limit the conversion efficiency of silicon solar cells were studied. The effects of changes in solar cell geometry such as layer thickness on performance were examined. The effects of various antireflecting layers were also examined. It was found that any single film antireflecting layer results in a significant surface loss of photons. The use of surface texturing techniques or low loss antireflecting layers can enhance by several percentage points the conversion efficiency of silicon cells. The basic differences between n(+)-p-p(+) and p(+)-n-n(+) cells are treated. A significant part of the study was devoted to the importance of surface region lifetime and heavy doping effects on efficiency. Heavy doping bandgap reduction effects are enhanced by low surface layer lifetimes, and conversely, the reduction in solar cell efficiency due to low surface layer lifetime is further enhanced by heavy doping effects. A series of computer studies is reported which seeks to determine the best cell structure and doping levels for maximum efficiency.

  13. Wind energy conversion system

    DOEpatents

    Longrigg, Paul

    1987-01-01

    The wind energy conversion system includes a wind machine having a propeller connected to a generator of electric power, the propeller rotating the generator in response to force of an incident wind. The generator converts the power of the wind to electric power for use by an electric load. Circuitry for varying the duty factor of the generator output power is connected between the generator and the load to thereby alter a loading of the generator and the propeller by the electric load. Wind speed is sensed electro-optically to provide data of wind speed upwind of the propeller, to thereby permit tip speed ratio circuitry to operate the power control circuitry and thereby optimize the tip speed ratio by varying the loading of the propeller. Accordingly, the efficiency of the wind energy conversion system is maximized.

  14. Fuel Cycle System Analysis Implications of Sodium-Cooled Metal-Fueled Fast Reactor Transuranic Conversion Ratio

    SciTech Connect

    Steven J. Piet; Edward A. Hoffman; Samuel E. Bays; Gretchen E. Matthern; Jacob J. Jacobson; Ryan Clement; David W. Gerts

    2013-03-01

    If advanced fuel cycles are to include a large number of fast reactors (FRs), what should be the transuranic (TRU) conversion ratio (CR)? The nuclear energy era started with the assumption that they should be breeder reactors (CR > 1), but the full range of possible CRs eventually received attention. For example, during the recent U.S. Global Nuclear Energy Partnership program, the proposal was burner reactors (CR < 1). Yet, more recently, Massachusetts Institute of Technology's "Future of the Nuclear Fuel Cycle" proposed CR [approximately] 1. Meanwhile, the French company EDF remains focused on breeders. At least one of the reasons for the differences of approach is different fuel cycle objectives. To clarify matters, this paper analyzes the impact of TRU CR on many parameters relevant to fuel cycle systems and therefore spans a broad range of topic areas. The analyses are based on a FR physics parameter scan of TRU CR from 0 to [approximately]1.8 in a sodium-cooled metal-fueled FR (SMFR), in which the fuel from uranium-oxide-fueled light water reactors (LWRs) is recycled directly to FRs and FRs displace LWRs in the fleet. In this instance, the FRs are sodium cooled and metal fueled. Generally, it is assumed that all TRU elements are recycled, which maximizes uranium ore utilization for a given TRU CR and waste radiotoxicity reduction and is consistent with the assumption of used metal fuel separated by electrochemical means. In these analyses, the fuel burnup was constrained by imposing a neutron fluence limit to fuel cladding to the same constant value. This paper first presents static, time-independent measures of performance for the LWR [right arrow] FR fuel cycle, including mass, heat, gamma emission, radiotoxicity, and the two figures of merit for materials for weapon attractiveness developed by C. Bathke et al. No new fuel cycle will achieve a static equilibrium in the foreseeable future. Therefore, additional analyses are shown with dynamic, time

  15. Neighborhood effects on an individual's health using neighborhood measurements developed by factor analysis and cluster analysis.

    PubMed

    Li, Yu-Sheng; Chuang, Ying-Chih

    2009-01-01

    This study suggests a multivariate-structural approach combining factor analysis and cluster analysis that could be used to examine neighborhood effects on an individual's health. Data were from the Taiwan Social Change Survey conducted in 1990, 1995, and 2000. In total, 5,784 women and men aged over 20 years living in 428 neighborhoods were interviewed. Participants' addresses were geocoded with census data for measuring neighborhood-level characteristics. The factor analysis was applied to identify neighborhood dimensions, which were used as entities in the cluster analysis to generate a neighborhood typology. The factor analysis generated three neighborhood dimensions: neighborhood education, age structure, and neighborhood family structure and employment. The cluster analysis generated six types of neighborhoods with combinations of the three neighborhood dimensions. Multilevel binomial regression models were used to assess the effects of neighborhoods on an individual's health. The results showed that the biggest health differences were between two neighborhood types: (1) the highest concentration of inhabitants younger than 15 years, a moderate education level, and a moderate level of single-parent families and (2) the highest educational level, a median level of single-parent families, and a median level of elderly concentrations. Individuals living in the first type had significantly higher chances of having functional limitations and poor self-rated health than the individuals in the second neighborhood type. Our study suggests that the multivariate-structural approach improves neighborhood measurements by addressing neighborhood diversity and examining how an individual's health varies in different neighborhood contexts. PMID:18629650

  16. Accelerated Gibbs Sampling for Infinite Sparse Factor Analysis

    SciTech Connect

    Andrzejewski, D M

    2011-09-12

    The Indian Buffet Process (IBP) gives a probabilistic model of sparse binary matrices with an unbounded number of columns. This construct can be used, for example, to model a fixed numer of observed data points (rows) associated with an unknown number of latent features (columns). Markov Chain Monte Carlo (MCMC) methods are often used for IBP inference, and in this technical note, we provide a detailed review of the derivations of collapsed and accelerated Gibbs samplers for the linear-Gaussian infinite latent feature model. We also discuss and explain update equations for hyperparameter resampling in a 'full Bayesian' treatment and present a novel slice sampler capable of extending the accelerated Gibbs sampler to the case of infinite sparse factor analysis by allowing the use of real-valued latent features.

  17. Statistical Analysis of Factors Affecting Child Mortality in Pakistan.

    PubMed

    Ahmed, Zoya; Kamal, Asifa; Kamal, Asma

    2016-06-01

    Child mortality is a composite indicator reflecting economic, social, environmental, healthcare services, and their delivery situation in a country. Globally, Pakistan has the third highest burden of fetal, maternal, and child mortality. Factors affecting child mortality in Pakistan are investigated by using Binary Logistic Regression Analysis. Region, education of mother, birth order, preceding birth interval (the period between the previous child birth and the index child birth), size of child at birth, and breastfeeding and family size were found to be significantly important with child mortality in Pakistan. Child mortality decreased as level of mother's education, preceding birth interval, size of child at birth, and family size increased. Child mortality was found to be significantly higher in Balochistan as compared to other regions. Child mortality was low for low birth orders. Child survival was significantly higher for children who were breastfed as compared to those who were not. PMID:27354000

  18. Male sexual coercion: analysis of a few associated factors.

    PubMed

    Sierra, Juan Carlos; Gutiérrez-Quintanilla, Ricardo; Bermúdez, María Paz; Buela-Casal, Gualberto

    2009-08-01

    The purpose of this study was to assess, in a sample of 700 university students ages 18 to 40 years in El Salvador, the importance of sociodemographic variables (age, having a partner, and frequency of religious practice), personality traits (anger, hostility, and aggressiveness), sexual attitudes, and male chauvinist attitudes (erotophilia, double standard, and rape supportive attitudes) in explaining male sexual coercion. All these variables were assessed. Once the effect of social desirability had been controlled, the analysis showed the importance of trait anger along with a favorable attitude toward the use of violence against women, double standard, and negative attitudes toward sexuality in explaining male sexual coercion. Religious involvement, however, may act as a protective factor against such violence. Multidimensional models are needed to explain sexual violence against women by men in heterosexual relationships. PMID:19810434

  19. Bayesian analysis of factors associated with fibromyalgia syndrome subjects

    NASA Astrophysics Data System (ADS)

    Jayawardana, Veroni; Mondal, Sumona; Russek, Leslie

    2015-01-01

    Factors contributing to movement-related fear were assessed by Russek, et al. 2014 for subjects with Fibromyalgia (FM) based on the collected data by a national internet survey of community-based individuals. The study focused on the variables, Activities-Specific Balance Confidence scale (ABC), Primary Care Post-Traumatic Stress Disorder screen (PC-PTSD), Tampa Scale of Kinesiophobia (TSK), a Joint Hypermobility Syndrome screen (JHS), Vertigo Symptom Scale (VSS-SF), Obsessive-Compulsive Personality Disorder (OCPD), Pain, work status and physical activity dependent from the "Revised Fibromyalgia Impact Questionnaire" (FIQR). The study presented in this paper revisits same data with a Bayesian analysis where appropriate priors were introduced for variables selected in the Russek's paper.

  20. Transcription factor motif quality assessment requires systematic comparative analysis

    PubMed Central

    Kibet, Caleb Kipkurui; Machanick, Philip

    2016-01-01

    Transcription factor (TF) binding site prediction remains a challenge in gene regulatory research due to degeneracy and potential variability in binding sites in the genome. Dozens of algorithms designed to learn binding models (motifs) have generated many motifs available in research papers with a subset making it to databases like JASPAR, UniPROBE and Transfac. The presence of many versions of motifs from the various databases for a single TF and the lack of a standardized assessment technique makes it difficult for biologists to make an appropriate choice of binding model and for algorithm developers to benchmark, test and improve on their models. In this study, we review and evaluate the approaches in use, highlight differences and demonstrate the difficulty of defining a standardized motif assessment approach. We review scoring functions, motif length, test data and the type of performance metrics used in prior studies as some of the factors that influence the outcome of a motif assessment. We show that the scoring functions and statistics used in motif assessment influence ranking of motifs in a TF-specific manner. We also show that TF binding specificity can vary by source of genomic binding data. We also demonstrate that information content of a motif is not in isolation a measure of motif quality but is influenced by TF binding behaviour. We conclude that there is a need for an easy-to-use tool that presents all available evidence for a comparative analysis. PMID:27092243

  1. Assessment and benchmarking of the impact to gamma dose rate employing different photon-to-dose conversion factors using MCNPX code at the decommissioning stage of Ignalina Nuclear Power Plant.

    PubMed

    Stankunas, Gediminas; Pabarcius, Raimondas; Tonkunas, Aurimas

    2014-11-01

    A comparative study was performed to reveal the impact of several photon-to-dose conversion factors for gamma dose rate calculations when applied to heterogeneous environment in the case of decommission stage of the Ignalina Nuclear Power Plant. The following set of conversion factors were investigated by employing the Monte Carlo N-particle transport (MCNPX) code derived from the recommendations given in ICRP-21, ICRP-74 and ANSI/ANS-6.1.1 standards (1977 and 1991), based on the experiments performed for gamma radiation dose rate measurements inside the deplanting Emergency Core Cooling System tank. MCNPX precise simulation and the benchmark between the conversion coefficients highlighted the impact to the results for the selected case of this investigation. The results revealed that the data from the ANSI/ANS-6.1.1 1991 publication are reliable for various dose and shielding calculations in the case of decontamination of radioactive equipment and similar applications since it showed a statistically satisfied agreement between the simulation results and experimental data. These tendencies suggest that the radiological protection system currently adopted in NPP during the decommissioning stage can be characterised using ANSI/ANS-6.1.1 1991 standards with respect to gamma dosimetry. PMID:24990828

  2. Risk analysis of the thermal sterilization process. Analysis of factors affecting the thermal resistance of microorganisms.

    PubMed

    Akterian, S G; Fernandez, P S; Hendrickx, M E; Tobback, P P; Periago, P M; Martinez, A

    1999-03-01

    A risk analysis was applied to experimental heat resistance data. This analysis is an approach for processing experimental thermobacteriological data in order to study the variability of D and z values of target microorganisms depending on the deviations range of environmental factors, to determine the critical factors and to specify their critical tolerance. This analysis is based on sets of sensitivity functions applied to a specific case of experimental data related to the thermoresistance of Clostridium sporogenes and Bacillus stearothermophilus spores. The effect of the following factors was analyzed: the type of target microorganism; nature of the heating substrate; pH, temperature; type of acid employed and NaCl concentration. The type of target microorganism to be inactivated, the nature of the substrate (reference or real food) and the heating temperature were identified as critical factors, determining about 90% of the alteration of the microbiological risk. The effect of the type of acid used for the acidification of products and the concentration of NaCl can be assumed to be negligible factors for the purposes of engineering calculations. The critical non-uniformity in temperature during thermobacteriological studies was set as 0.5% and the critical tolerances of pH value and NaCl concentration were 5%. These results are related to a specific case study, for that reason their direct generalization is not correct. PMID:10357273

  3. Catalytic conversions of chlorodecalin

    SciTech Connect

    Takhistov, U.V.; Kovyazin, V.E.

    1985-10-01

    This paper studies catalytic conversions of chlorinated decahydronaphthalene (chlorodecalin), since the introduction of chlorine into the hydrocarbon molecule would facilitate formation of the original carbonium ion required for conversion to adamantane. Analysis of the fractions obtained showed that two main products are formed: the tricyclic hydrocarbon C/sub 10/H/sub 16/ and the bicyclic hydrocarbon C/sub 10/H/sub 16/. Therefore, the C/sub 10/H/sub 17/ cation formed by removal of chlorine from chlorodecalin, C/sub 10/H/sub 17/CI, undergoes changes in two directions: addition of hydride ions from other chlorodecalin molecules to form Decalin, and loss of a proton to give a tricyclic system of the adamantane weries and its isomer. Introduction of a substituent (chlorine) into the Decalin molecule made it possible to conduct the process at low temperatures.

  4. Factor Analysis of Drawings: Application to College Student Models of the Greenhouse Effect

    ERIC Educational Resources Information Center

    Libarkin, Julie C.; Thomas, Stephen R.; Ording, Gabriel

    2015-01-01

    Exploratory factor analysis was used to identify models underlying drawings of the greenhouse effect made by over 200 entering university freshmen. Initial content analysis allowed deconstruction of drawings into salient features, with grouping of these features via factor analysis. A resulting 4-factor solution explains 62% of the data variance,…

  5. Physics Metacognition Inventory Part Ii: Confirmatory Factor Analysis and Rasch Analysis

    ERIC Educational Resources Information Center

    Taasoobshirazi, Gita; Bailey, MarLynn; Farley, John

    2015-01-01

    The Physics Metacognition Inventory was developed to measure physics students' metacognition for problem solving. In one of our earlier studies, an exploratory factor analysis provided evidence of preliminary construct validity, revealing six components of students' metacognition when solving physics problems including knowledge of cognition,…

  6. Crucial issues in the applied analysis of verbal behavior: reflections on crucial conversations: tools for talking when the stakes are high.

    PubMed

    Critchfield, Thomas S

    2010-01-01

    A popular-press self-help manual is reviewed with an eye toward two issues. First, the popularity of such books documents the existence of considerable demand for technologies that address the everyday problems (in the present case, troublesome conversations) of nondisordered individuals. Second, many ideas invoked in popular-press books may be interpretable within an analysis of verbal behavior, although much more than casual translation is required to develop technologies that outperform self-help manuals. I discuss several challenges relevant to research, theory refinement, technology development, and dissemination, and conclude that behavioral alternatives to existing popular-press resources may not emerge anytime soon. PMID:22477467

  7. Crucial Issues in the Applied Analysis of Verbal Behavior: Reflections on Crucial Conversations: Tools for Talking When the Stakes Are High

    PubMed Central

    Critchfield, Thomas S

    2010-01-01

    A popular-press self-help manual is reviewed with an eye toward two issues. First, the popularity of such books documents the existence of considerable demand for technologies that address the everyday problems (in the present case, troublesome conversations) of nondisordered individuals. Second, many ideas invoked in popular-press books may be interpretable within an analysis of verbal behavior, although much more than casual translation is required to develop technologies that outperform self-help manuals. I discuss several challenges relevant to research, theory refinement, technology development, and dissemination, and conclude that behavioral alternatives to existing popular-press resources may not emerge anytime soon. PMID:22477467

  8. Laser-induced breakdown spectroscopy technique for quantitative analysis of aqueous solution using matrix conversion based on plant fiber spunlaced nonwovens.

    PubMed

    Chen, Chenghan; Niu, Guanghui; Shi, Qi; Lin, Qingyu; Duan, Yixiang

    2015-10-01

    In the present work, laser-induced breakdown spectroscopy (LIBS) was applied to detect concentrations of chromium and nickel in aqueous solution in the form of matrix conversion using plant fiber spunlaced nonwovens as a solid-phase support, which can effectively avoid the inherent difficulties such as splashing, a quenching effect, and a shorter plasma lifetime during the liquid LIBS analysis. Drops of the sample solution were transferred to the plant fiber spunlaced nonwovens surface and uniformly diffused from the center to the whole area of the substrate. Owing to good hydrophilicity, the plant fiber spunlaced nonwovens can hold more of the liquid sample, and the surface of this material never wrinkles after being dried in a drying oven, which can effectively reduce the deviation during the LIBS analysis. In addition, the plant fiber spunlaced nonwovens used in the present work are relatively convenient and low cost. Also, the procedure of analysis was simple and fast, which are the unique features of LIBS technology. Therefore, this method has potential applications for practical and in situ analyses. To achieve sensitive elemental detection, the optimal delay time in this experiment was investigated. Under the optimized condition, the limits of detection for Cr and Ni are 0.7 and 5.7  μg·mL(-1), respectively. The results obtained in the present study show that the matrix conversion method is a feasible option for analyzing heavy metals in aqueous solutions by LIBS technology. PMID:26479603

  9. Energy conversion and storage program

    NASA Astrophysics Data System (ADS)

    1990-12-01

    The Energy Conversion and Storage Program applies chemical and chemical engineering principles to solve problems in (1) production of new synthetic fuels; (2) development of high-performance rechargeable batteries and fuel cells; (3) development of advanced thermochemical processes for energy storage; (4) characterization of complex chemical processes; and (5) the application of novel materials for energy conversion and transmission. Projects focus on transport-process principles, chemical kinetics, thermodynamics, separation processes, organic and physical chemistry, and advanced methods of analysis. The following five areas are discussed: electrochemical energy storage and conversion; microstructured materials; biotechnology; fossil fuels; and high temperature superconducting processing. Papers have been processed separately for inclusion on the data base.

  10. Weightlifter Lumbar Physiology Health Influence Factor Analysis of Sports Medicine

    PubMed Central

    Zhang, Xiangyang

    2015-01-01

    Chinese women's weightlifting project has been in the advanced world level, suggests that the Chinese coaches and athletes have many successful experience in the weight lifting training. Little weight lifting belongs to high-risk sports, however, to the lumbar spine injury, some young good athletes often due to lumbar trauma had to retire, and the national investment and athletes toil is regret things. This article from the perspective of sports medicine, weightlifting athletes training situation analysis and put forward Suggestions, aimed at avoiding lumbar injury, guarantee the health of athletes. In this paper, first of all to 50 professional women's weightlifting athletes doing investigation, found that 82% of the athletes suffer from lumbar disease symptoms, the reason is mainly composed of lumbar strain, intensity is too large, motion error caused by three factors. From the Angle of sports medicine and combined with the characteristics of the structure of human body skeleton athletes lumbar structural mechanics analysis, find out the lumbar force's two biggest technical movement, study, and regulate the action standard, so as to minimize lumbar force, for athletes to contribute to the health of the lumbar spine. PMID:26981162

  11. Application of homomorphic signal processing to stress wave factor analysis

    NASA Technical Reports Server (NTRS)

    Karagulle, H.; Williams, J. H., Jr.; Lee, S. S.

    1985-01-01

    The stress wave factor (SWF) signal, which is the output of an ultrasonic testing system where the transmitting and receiving transducers are coupled to the same face of the test structure, is analyzed in the frequency domain. The SWF signal generated in an isotropic elastic plate is modelled as the superposition of successive reflections. The reflection which is generated by the stress waves which travel p times as a longitudinal (P) wave and s times as a shear (S) wave through the plate while reflecting back and forth between the bottom and top faces of the plate is designated as the reflection with p, s. Short-time portions of the SWF signal are considered for obtaining spectral information on individual reflections. If the significant reflections are not overlapped, the short-time Fourier analysis is used. A summary of the elevant points of homomorphic signal processing, which is also called cepstrum analysis, is given. Homomorphic signal processing is applied to short-time SWF signals to obtain estimates of the log spectra of individual reflections for cases in which the reflections are overlapped. Two typical SWF signals generated in aluminum plates (overlapping and non-overlapping reflections) are analyzed.

  12. Application of homomorphic signal processing to stress wave factor analysis

    NASA Technical Reports Server (NTRS)

    Williams, J. H., Jr.; Lee, S. S.; Karaguelle, H.

    1985-01-01

    The stress wave factor (SWF) signal, which is the output of an ultrasonic testing system where the transmitting and receiving transducers are coupled to the same face of the test structure, is analyzed in the frequency domain. The SWF signal generated in an isotropic elastic plate is modelled as the superposition of successive reflections. The reflection which is generated by the stress waves which travel P times as a longitudinal (P) wave and s times as a shear (S) wave through the plate while reflecting back and forth between the bottom and top faces of the plate is designated as the reflection with P, s. Short-time portions of the SWF signal are considered for obtaining spectral information on individual reflections. If the significant reflections are not overlapped, the short-time Fourier analysis is used. A summary of the elevant points of homomorphic signal processing, which is also called cepstrum analysis, is given. Homomorphic signal processing is applied to short-time SWF signals to obtain estimates of the log spectra of individual reflections for cases in which the reflections are overlapped. Two typical SWF signals generated in aluminum plates (overlapping and non-overlapping reflections) are analyzed.

  13. Analysis and calculation of electronic properties and light absorption of defective sulfur-doped silicon and theoretical photoelectric conversion efficiency.

    PubMed

    Jiang, He; Chen, Changshui

    2015-04-23

    Most material properties can be traced to electronic structures. Black silicon produced from SF6 or sulfur powder via irradiation with femtosecond laser pulses displays decreased infrared absorption after annealing, with almost no corresponding change in visible light absorption. The high-intensity laser pulses destroy the original crystal structure, and the doping element changes the material performance. In this work, the structural and electronic properties of several sulfur-doped silicon systems are investigated using first principle calculations. Depending on the sulfur concentration (level of doping) and the behavior of the sulfur atoms in the silicon lattice, different states or an absence of states are exhibited, compared with the undoped system. Moreover, the visible-infrared light absorption intensities are structure specific. The results of our theoretical calculations show that the conversion efficiency of sulfur-doped silicon solar cells depends on the sulfur concentrations. Additionally, two types of defect configurations exhibit light absorption characteristics that differ from the other configurations. These two structures produce a rapid increase in the theoretical photoelectric conversion efficiency in the range of the specific chemical potential studied. By controlling the positions of the atomic sulfur and the sulfur concentration in the preparation process, an efficient photovoltaic (PV) material may be obtainable. PMID:25798659

  14. Bio-energy conversion performance, biodegradability, and kinetic analysis of different fruit residues during discontinuous anaerobic digestion.

    PubMed

    Zhao, Chen; Yan, Hu; Liu, Yan; Huang, Yan; Zhang, Ruihong; Chen, Chang; Liu, Guangqing

    2016-06-01

    Huge amounts of fruit residues are produced and abandoned annually. The high moisture and organic contents of these residues makes them a big problem to the environment. Conversely, they are a potential resource to the world. Anaerobic digestion is a good way to utilize these organic wastes. In this study, the biomethane conversion performances of a large number of fruit residues were determined and compared using batch anaerobic digestion, a reliable and easily accessible method. The results showed that some fruit residues containing high contents of lipids and carbohydrates, such as loquat peels and rambutan seeds, were well fit for anaerobic digestion. Contrarily, residues with high lignin content were strongly recommended not to be used as a single substrate for methane production. Multiple linear regression model was adopted to simulate the correlation between the organic component of these fruit residues and their experimental methane yield, through which the experimental methane yield could probably be predicted for any other fruit residues. Four kinetic models were used to predict the batch anaerobic digestion process of different fruit residues. It was shown that the modified Gompertz and Cone models were better fit for the fruit residues compared to the first-order and Fitzhugh models. The first findings of this study could provide useful reference and guidance for future studies regarding the applications and potential utilization of fruit residues. PMID:27039123

  15. Analysis of regional MRI volumes and thicknesses as predictors of conversion from mild cognitive impairment to Alzheimer's disease.

    PubMed

    Liu, Yawu; Paajanen, Teemu; Zhang, Yi; Westman, Eric; Wahlund, Lars-Olof; Simmons, Andrew; Tunnard, Catherine; Sobow, Tomasz; Mecocci, Patrizia; Tsolaki, Magda; Vellas, Bruno; Muehlboeck, Sebastian; Evans, Alan; Spenger, Christian; Lovestone, Simon; Soininen, Hilkka

    2010-08-01

    We determined predictors of conversion to Alzheimer's disease (AD) from mild cognitive impairment (MCI) with automated magnetic resonance imaging (MRI) regional cortical volume and thickness measures. One hundred amnestic MCI subjects, 118 AD patients, and 94 age-matched healthy controls were selected from AddNeuroMed study. Twenty-four regional cortical volumes and 34 cortical thicknesses were measured with automated image processing software at baseline. Twenty-one subjects converted from MCI to AD determined with the cognitive tests at baseline and 1 year later. The hippocampus, amygdala, and caudate volumes were significantly smaller in progressive MCI subjects than in controls and stable MCI subjects. The cortical volumes achieved higher predictive accuracy than did cognitive tests or cortical thickness. Combining the volumes, thicknesses, and cognitive tests did not improve the accuracy. The volume of amygdala and caudate were independent variables in predicting conversion from MCI to AD. We conclude that regional cortical volume measures are more powerful than those common cognitive tests we used in identifying AD patients at the very earliest stage of the disease. PMID:20447732

  16. Using conversation analysis to explore the recurrence of a topic in the talk of a boy with an autism spectrum disorder.

    PubMed

    Stribling, Penny; Rae, John; Dickerson, Paul

    2009-08-01

    Some higher functioning individuals with autism spectrum disorders (ASDs) are reported to produce perseverative talk, especially around 'special interests'. Topic perseveration is a form of pragmatic impairment captured in Prizant and Rydell's (1993) continuum of unconventional verbal behaviour in autism. Although widely reported, there is little systematic empirical research into this phenomenon. This paper considers the utility of Conversation Analysis in developing knowledge in this area, drawing upon data involving a boy with an ASD interacting with a researcher and a mobile robot platform. Although a frequency analysis of the boy's talk on a single topic may suggest that it is perseverative in nature, in a sequential analysis of both talk and non-spoken activities this study aims to show how these may be interactionally-embedded. It is suggested that, in considering the interactional salience of apparently perseverative talk, it can be useful to explore the participation framework in which the topic is revisited. PMID:19669991

  17. Recovery of Weak Factor Loadings When Adding the Mean Structure in Confirmatory Factor Analysis: A Simulation Study

    PubMed Central

    Ximénez, Carmen

    2016-01-01

    This article extends previous research on the recovery of weak factor loadings in confirmatory factor analysis (CFA) by exploring the effects of adding the mean structure. This issue has not been examined in previous research. This study is based on the framework of Yung and Bentler (1999) and aims to examine the conditions that affect the recovery of weak factor loadings when the model includes the mean structure, compared to analyzing the covariance structure alone. A simulation study was conducted in which several constraints were defined for one-, two-, and three-factor models. Results show that adding the mean structure improves the recovery of weak factor loadings and reduces the asymptotic variances for the factor loadings, particularly for the models with a smaller number of factors and a small sample size. Therefore, under certain circumstances, modeling the means should be seriously considered for covariance models containing weak factor loadings. PMID:26779071

  18. Validation of the Child Sex Abuse Attitude Scale through Confirmatory Factor Analysis.

    ERIC Educational Resources Information Center

    Ferrara, F. Felicia

    1999-01-01

    A validation study of the Child Sex Abuse Attitude Scale (CSAAS) used confirmatory factor analysis to examine factor structure. Results from a sample of 215 school psychologists supported the hypothesized factor structure of the CSAAS, indicating the plausibility of a four-factor first-order and a single-factor higher order structure for the…

  19. Scale-Free Nonparametric Factor Analysis: A User-Friendly Introduction with Concrete Heuristic Examples.

    ERIC Educational Resources Information Center

    Mittag, Kathleen Cage

    Most researchers using factor analysis extract factors from a matrix of Pearson product-moment correlation coefficients. A method is presented for extracting factors in a non-parametric way, by extracting factors from a matrix of Spearman rho (rank correlation) coefficients. It is possible to factor analyze a matrix of association such that…

  20. An Exploratory Factor Analysis of the Differential Ability Scales.

    ERIC Educational Resources Information Center

    Dunham, Mardis D.; McIntosh, David E.

    The primary goal of this study was to investigate the underlying structure of the Differential Ability Scales (DAS) using Exploratory Principal Axis Factoring (PAF) with 62 nonclinical preschoolers. While previous factor analyses of the DAS Core subtests revealed the derivation of two distinct factors, the current results revealed only one factor,…