Sample records for factor analysis procedure

  1. Extension Procedures for Confirmatory Factor Analysis

    ERIC Educational Resources Information Center

    Nagy, Gabriel; Brunner, Martin; Lüdtke, Oliver; Greiff, Samuel

    2017-01-01

    We present factor extension procedures for confirmatory factor analysis that provide estimates of the relations of common and unique factors with external variables that do not undergo factor analysis. We present identification strategies that build upon restrictions of the pattern of correlations between unique factors and external variables. The…

  2. Risk Factors Analysis for Occurrence of Asymptomatic Bacteriuria After Endourological Procedures

    PubMed Central

    Junuzovic, Dzelaludin; Hasanbegovic, Munira

    2014-01-01

    Introduction: Endourological procedures are performed according to the principles of aseptic techniques, jet still in certain number of patients urinary tract infections may occur. Considering the risk of urinary tract infection, there is no unique opinion about the prophylactic use of antibiotics in endourological procedures. Goal: The objective of this study was to determine the connection between endourological procedures and occurrence of urinary infections and to analyze the risk factors of urinary infection for patients who were hospitalized at the Urology Clinic of the Clinical Center University of Sarajevo CCUS. Materials and Methods: The research was conducted as a prospective study on a sample of 208 patients of both genders, who were hospitalized at the Urology Clinic of the CCUS and to whom some endourological procedure was indicated for diagnostic or therapeutic purposes. We analyzed data from patient’s histories of illness, laboratory tests taken at admission and after endourological procedures, also surgical programs for endoscopic procedures. All patients were clinically examined prior to endoscopic procedures while after the treatment attention was focused to the symptoms of urinary tract infections. Results: Statistical analysis of the tested patients indicates that there is no significant difference in the presence of postoperative, compared to preoperative bacteriuria, which implies that the endourological procedures are safe procedures in terms of urinary tract infections. Preoperatively, the most commonly isolated bacteria was Escherichia coli (30.9%) and postoperatively, Enterococcus faecalis (25%). Statistically significant effect on the occurrence of postoperative bacteriuria has preoperative bacteriuria, duration of postoperative catheterization, and duration of hospitalization. Conclusion: In everyday urological practice, it is very important to identify and control risk factors for the development of urinary infection after

  3. Human Factors Process Task Analysis Liquid Oxygen Pump Acceptance Test Procedure for the Advanced Technology Development Center

    NASA Technical Reports Server (NTRS)

    Diorio, Kimberly A.

    2002-01-01

    A process task analysis effort was undertaken by Dynacs Inc. commencing in June 2002 under contract from NASA YA-D6. Funding was provided through NASA's Ames Research Center (ARC), Code M/HQ, and Industrial Engineering and Safety (IES). The John F. Kennedy Space Center (KSC) Engineering Development Contract (EDC) Task Order was 5SMA768. The scope of the effort was to conduct a Human Factors Process Failure Modes and Effects Analysis (HF PFMEA) of a hazardous activity and provide recommendations to eliminate or reduce the effects of errors caused by human factors. The Liquid Oxygen (LOX) Pump Acceptance Test Procedure (ATP) was selected for this analysis. The HF PFMEA table (see appendix A) provides an analysis of six major categories evaluated for this study. These categories include Personnel Certification, Test Procedure Format, Test Procedure Safety Controls, Test Article Data, Instrumentation, and Voice Communication. For each specific requirement listed in appendix A, the following topics were addressed: Requirement, Potential Human Error, Performance-Shaping Factors, Potential Effects of the Error, Barriers and Controls, Risk Priority Numbers, and Recommended Actions. This report summarizes findings and gives recommendations as determined by the data contained in appendix A. It also includes a discussion of technology barriers and challenges to performing task analyses, as well as lessons learned. The HF PFMEA table in appendix A recommends the use of accepted and required safety criteria in order to reduce the risk of human error. The items with the highest risk priority numbers should receive the greatest amount of consideration. Implementation of the recommendations will result in a safer operation for all personnel.

  4. A Class of Factor Analysis Estimation Procedures with Common Asymptotic Sampling Properties

    ERIC Educational Resources Information Center

    Swain, A. J.

    1975-01-01

    Considers a class of estimation procedures for the factor model. The procedures are shown to yield estimates possessing the same asymptotic sampling properties as those from estimation by maximum likelihood or generalized last squares, both special members of the class. General expressions for the derivatives needed for Newton-Raphson…

  5. Abdominoplasty: Risk Factors, Complication Rates, and Safety of Combined Procedures.

    PubMed

    Winocour, Julian; Gupta, Varun; Ramirez, J Roberto; Shack, R Bruce; Grotting, James C; Higdon, K Kye

    2015-11-01

    Among aesthetic surgery procedures, abdominoplasty is associated with a higher complication rate, but previous studies are limited by small sample sizes or single-institution experience. A cohort of patients who underwent abdominoplasty between 2008 and 2013 was identified from the CosmetAssure database. Major complications were recorded. Univariate and multivariate analysis was performed evaluating risk factors, including age, smoking, body mass index, sex, diabetes, type of surgical facility, and combined procedures. The authors identified 25,478 abdominoplasties from 183,914 procedures in the database. Of these, 8,975 patients had abdominoplasty alone and 16,503 underwent additional procedures. The number of complications recorded was 1,012 (4.0 percent overall rate versus 1.4 percent in other aesthetic surgery procedures). Of these, 31.5 percent were hematomas, 27.2 percent were infections and 20.2 percent were suspected or confirmed venous thromboembolism. On multivariate analysis, significant risk factors (p < 0.05) included male sex (relative risk, 1.8), age 55 years or older (1.4), body mass index greater than or equal to 30 (1.3), multiple procedures (1.5), and procedure performance in a hospital or surgical center versus office-based surgical suite (1.6). Combined procedures increased the risk of complication (abdominoplasty alone, 3.1 percent; with liposuction, 3.8 percent; breast procedure, 4.3 percent; liposuction and breast procedure, 4.6 percent; body-contouring procedure, 6.8 percent; liposuction and body-contouring procedure, 10.4 percent). Abdominoplasty is associated with a higher complication rate compared with other aesthetic procedures. Combined procedures can significantly increase complication rates and should be considered carefully in higher risk patients. Risk, II.

  6. Factor Retention in Exploratory Factor Analysis: A Comparison of Alternative Methods.

    ERIC Educational Resources Information Center

    Mumford, Karen R.; Ferron, John M.; Hines, Constance V.; Hogarty, Kristine Y.; Kromrey, Jeffery D.

    This study compared the effectiveness of 10 methods of determining the number of factors to retain in exploratory common factor analysis. The 10 methods included the Kaiser rule and a modified Kaiser criterion, 3 variations of parallel analysis, 4 regression-based variations of the scree procedure, and the minimum average partial procedure. The…

  7. Current outcomes and risk factors for the Norwood procedure.

    PubMed

    Stasik, Chad N; Gelehrter, S; Goldberg, Caren S; Bove, Edward L; Devaney, Eric J; Ohye, Richard G

    2006-02-01

    Tremendous strides have been made in the outcomes for hypoplastic left heart syndrome and other functional single-ventricle malformations over the past 25 years. This progress relates primarily to improvements in survival for patients undergoing the Norwood procedure. Previous reports on risk factors have been on smaller groups of patients or collected over relatively long periods of time, during which management has evolved. We analyzed our current results for the Norwood procedure with attention to risk factors for poor outcome. A single-institution review of all patients undergoing a Norwood procedure for a single-ventricle malformation from May 1, 2001, through April 30, 2003, was performed. Patient demographics, anatomy, clinical condition, associated anomalies, operative details, and outcomes were recorded. Of the 111 patients, there were 23 (21%) hospital deaths. Univariate analysis revealed noncardiac abnormalities (genetic or significant extracardiac diagnosis, P = .0018), gestational age (P = .03), diagnosis of unbalanced atrioventricular septal defect (P = .017), and weight of less than 2.5 kg (P = .0072) to be related to hospital death. On multivariate analysis, only weight of less than 2.5 kg and noncardiac abnormalities were found to be independent risk factors. Patients with either of these characteristics had a hospital survival of 52% (12/23), whereas those at standard risk had a survival of 86% (76/88). Although improvements in management might have lessened the effect of some of the traditionally reported risk factors related to variations in the cardiovascular anatomy, noncardiac abnormalities and low birth weight remain as a future challenge for the physician caring for the patient with single-ventricle physiology.

  8. Hierarchical Factoring Based On Image Analysis And Orthoblique Rotations.

    PubMed

    Stankov, L

    1979-07-01

    The procedure for hierarchical factoring suggested by Schmid and Leiman (1957) is applied within the framework of image analysis and orthoblique rotational procedures. It is shown that this approach necessarily leads to correlated higher order factors. Also, one can obtain a smaller number of factors than produced by typical hierarchical procedures.

  9. Groin hematoma after electrophysiological procedures-incidence and predisposing factors.

    PubMed

    Dalsgaard, Anja Borgen; Jakobsen, Christina Spåbæk; Riahi, Sam; Hjortshøj, Søren

    2014-10-01

    We evaluated the incidence and predisposing factors of groin hematomas after electrophysiological (EP) procedures. Prospective, observational study, enrolling consecutive patients after EP procedures (Atrial fibrillation: n = 151; Supraventricular tachycardia/Diagnostic EP: n = 82; Ventricular tachycardia: n = 18). Patients underwent manual compression for 10 min and 3 h post procedural bed rest. AF ablations were performed with INR 2-3, ACT > 300, and no protamine sulfate. Adhesive pressure dressings (APDs) were used if sheath size ≥ 10F; procedural time > 120 min; and BMI > 30. Patient-reported hematomas were recorded by a telephone follow-up after 2 weeks. Hematoma developed immediately in 26 patients (10%) and after 14 days significant hematoma was reported in 68 patients (27%). Regression analysis on sex, age, BMI 25, ACT 300, use of APD, sheath size and number, and complicated venous access was not associated with hematoma, either immediately after the procedure or after 14 days. Any hematoma presenting immediately after procedures was associated with patient-reported hematomas after 14 days, odds ratio 18.7 (CI 95%: 5.00-69.8; P < 0.001). Any hematoma immediately after EP procedures was the sole predictor of patient-reported hematoma after 2 weeks. Initiatives to prevent groin hematoma should focus on the procedure itself as well as post-procedural care.

  10. Risk factors for postoperative urinary tract infection following midurethral sling procedures.

    PubMed

    Doganay, Melike; Cavkaytar, Sabri; Kokanali, Mahmut Kuntay; Ozer, Irfan; Aksakal, Orhan Seyfi; Erkaya, Salim

    2017-04-01

    To identify the potential risk factors for urinary tract infections following midurethral sling procedures. 556 women who underwent midurethral sling procedure due to stress urinary incontinence over a four-year period were reviewed in this retrospective study. Of the study population, 280 women underwent TVT procedures and 276 women underwent TOT procedures. Patients were evaluated at 4-8 weeks postoperatively and were investigated for the occurrence of a urinary tract infection. Patients who experienced urinary tract infection were defined as cases, and patients who didn't were defined as controls. All data were collected from medical records. Multivariate logistic regression model was used to identify the risk factors for urinary tract infection. Of 556 women, 58 (10.4%) were defined as cases while 498 (89.6%) were controls. The mean age of women in cases (57.8±12.9years) was significantly greater than in controls (51.8±11.2years) (p<0.001). The presence of menopausal status, previous abdominal surgery, preoperative antibiotic treatment due to urinary tract infection, concomitant vaginal hysterectomy and cystocele repair, TVT procedure and postoperative postvoiding residual bladder volume ≥100ml were more common in cases than in controls. However, in multivariate regression analysis model presence of preoperative urinary tract infection [OR (95% CI)=0.1 (0.1-0.7); p=0.013], TVT procedure [OR (95% CI)=8.4 (3.1-22.3); p=0.000] and postoperative postvoiding residual bladder volume ≥100ml [OR (95% CI)=4.6 (1.1-19.2); p=0.036] were significant independent risk factors for urinary tract infection following midurethral slings CONCLUSION: Urinary tract infection after midurethral sling procedures is a relatively common complication. The presence of preoperative urinary tract infection, TVT procedure and postoperative postvoiding residual bladder volume ≥100ml may increase the risk of this complication. Identification of these factors could help surgeons to

  11. 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

  12. Bio-Oil Analysis Laboratory Procedures | Bioenergy | NREL

    Science.gov Websites

    Bio-Oil Analysis Laboratory Procedures Bio-Oil Analysis Laboratory Procedures NREL develops standard procedures have been validated and allow for reliable bio-oil analysis. Procedures Determination different hydroxyl groups (-OH) in pyrolysis bio-oil: aliphatic-OH, phenolic-OH, and carboxylic-OH. Download

  13. Human Factors Considerations for Area Navigation Departure and Arrival Procedures

    NASA Technical Reports Server (NTRS)

    Barhydt, Richard; Adams, Catherine A.

    2006-01-01

    Area navigation (RNAV) procedures are being implemented in the United States and around the world as part of a transition to a performance-based navigation system. These procedures are providing significant benefits and have also caused some human factors issues to emerge. Under sponsorship from the Federal Aviation Administration (FAA), the National Aeronautics and Space Administration (NASA) has undertaken a project to document RNAV-related human factors issues and propose areas for further consideration. The component focusing on RNAV Departure and Arrival Procedures involved discussions with expert users, a literature review, and a focused review of the NASA Aviation Safety Reporting System (ASRS) database. Issues were found to include aspects of air traffic control and airline procedures, aircraft systems, and procedure design. Major findings suggest the need for specific instrument procedure design guidelines that consider the effects of human performance. Ongoing industry and government activities to address air-ground communication terminology, design improvements, and chart-database commonality are strongly encouraged. A review of factors contributing to RNAV in-service errors would likely lead to improved system design and operational performance.

  14. The use of analysis of variance procedures in biological studies

    USGS Publications Warehouse

    Williams, B.K.

    1987-01-01

    The analysis of variance (ANOVA) is widely used in biological studies, yet there remains considerable confusion among researchers about the interpretation of hypotheses being tested. Ambiguities arise when statistical designs are unbalanced, and in particular when not all combinations of design factors are represented in the data. This paper clarifies the relationship among hypothesis testing, statistical modelling and computing procedures in ANOVA for unbalanced data. A simple two-factor fixed effects design is used to illustrate three common parametrizations for ANOVA models, and some associations among these parametrizations are developed. Biologically meaningful hypotheses for main effects and interactions are given in terms of each parametrization, and procedures for testing the hypotheses are described. The standard statistical computing procedures in ANOVA are given along with their corresponding hypotheses. Throughout the development unbalanced designs are assumed and attention is given to problems that arise with missing cells.

  15. Cosmetic Liposuction: Preoperative Risk Factors, Major Complication Rates, and Safety of Combined Procedures.

    PubMed

    Kaoutzanis, Christodoulos; Gupta, Varun; Winocour, Julian; Layliev, John; Ramirez, Roberto; Grotting, James C; Higdon, Kent

    2017-06-01

    Liposuction is among the most commonly performed aesthetic procedures, and is being performed increasingly as an adjunct to other procedures. To report the incidence and risk factors of significant complications after liposuction, and to determine whether adding liposuction to other cosmetic surgical procedures impacts the complication risk. A prospective cohort of patients who underwent liposuction between 2008 and 2013 was identified from the CosmetAssure database. Primary outcome was occurrence of major complications requiring emergency room visit, hospital admission, or reoperation within 30 days of the operation. Univariate and multivariate analysis evaluated risk factors including age, gender, body mass index (BMI), smoking, diabetes, type of surgical facility, and combined procedures. Of the 31,010 liposuction procedures, only 11,490 (37.1%) were performed as a solitary procedure. Liposuction alone had a major complication rate of 0.7% with hematoma (0.15%), pulmonary complications (0.1%), infection (0.1%), and confirmed venous thromboembolism (VTE) (0.06%) being the most common. Independent predictors of major complications included combined procedures (Relative Risk (RR) 4.81), age (RR 1.01), BMI (RR 1.05), and procedures performed in hospitals (RR 1.36). When examining specifically other aesthetic procedures performed alone or with liposuction, combined procedures had a higher risk of confirmed VTE (RR 5.65), pulmonary complications (RR 2.72), and infection (RR 2.41), but paradoxically lower hematoma risk (RR 0.77) than solitary procedures. Liposuction performed alone is a safe procedure with a low risk of major complications. Combined procedures, especially on obese or older individuals, can significantly increase complication rates. The impact of liposuction on the risk of hematoma in combined procedures needs further investigation. © 2017 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com

  16. Time to Procedure, Nuclear Imaging and Clinicopathological Characteristics as Predictive Factors for Sentinel Lymph Node Metastasis in Cutaneous Melanoma: A Single-Center Analysis.

    PubMed

    Jaukovic, Ljiljana; Rajović, Milica; Kandolf Sekulovic, Lidija; Radulovic, Marija; Stepic, Nenad; Mijuskovic, Zeljko; Petrov, Nenad; Ajdinovic, Boris

    2018-05-14

    Sentinel lymph node (SLN) biopsy is a widely accepted staging procedure for cutaneous melanoma patients who are at risk of clinically occult nodal metastases. Numerous predictive factors for regional lymph node metastases have been identified; however, few have been found to be reproducibly significant. Also, the role of blue dye in identification was questioned in recent trials. Time to procedure was also found to be predictive of SLN positivity, but this was not confirmed in other studies. In our study, predictive factors for metastatic involvement of SLN were analyzed, together with the role of addition blue dye in imaging on detection rate and false-negative SLN rate. An impact of time interval to procedure on the rate of SLN positivity was also explored. Data analysis was done in 362 cutaneous melanoma patients who underwent lymphoscintigraphy and SLN biopsy at our institution from 2010 to 2016, with a median follow-up of 29 months (1-98 months). To delineate the relation of each variable (demographical, time to procedure, and clinical and pathological variables, as well as the presence of in-transit nodes, the number of draining basins, and SLN localization on scintigraphy) with positive SLN status, we used univariate logistic regression with odds ratios representing effect size. Metastatic involvement SLN was found in 67 (18.8%) of 356 patients. Detection rate was similar with or without further intraoperative SLN identification with blue dye (98.8% vs 98.17%, P > 0.05). Time to procedure was not associated with higher SLN positivity rate (P > 0.05). In univariate analysis, Breslow thickness (P < 0.001), primary ulceration lesion (P = 0.001), and lymphovascular invasion (P = 0.006) were strongly correlated with SLN positivity, as well as the site of primary tumor (P = 0.024), tumor-infiltrating lymphocytes (TILs) (P = 0.021), and sex (P = 0.026). In multivariate analysis, Breslow thickness and TILs were found to be significant independent predictors of SLN

  17. Establishing Factor Validity Using Variable Reduction in Confirmatory Factor Analysis.

    ERIC Educational Resources Information Center

    Hofmann, Rich

    1995-01-01

    Using a 21-statement attitude-type instrument, an iterative procedure for improving confirmatory model fit is demonstrated within the context of the EQS program of P. M. Bentler and maximum likelihood factor analysis. Each iteration systematically eliminates the poorest fitting statement as identified by a variable fit index. (SLD)

  18. 32 CFR 989.37 - Procedures for analysis abroad.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 32 National Defense 6 2011-07-01 2011-07-01 false Procedures for analysis abroad. 989.37 Section... PROTECTION ENVIRONMENTAL IMPACT ANALYSIS PROCESS (EIAP) § 989.37 Procedures for analysis abroad. Procedures for analysis of environmental actions abroad are contained in 32 CFR part 187. That directive provides...

  19. Boolean Minimization and Algebraic Factorization Procedures for Fully Testable Sequential Machines

    DTIC Science & Technology

    1989-09-01

    Boolean Minimization and Algebraic Factorization Procedures for Fully Testable Sequential Machines Srinivas Devadas and Kurt Keutzer F ( Abstract In this...Projects Agency under contract number N00014-87-K-0825. Author Information Devadas : Department of Electrical Engineering and Computer Science, Room 36...MA 02139; (617) 253-0292. 0 * Boolean Minimization and Algebraic Factorization Procedures for Fully Testable Sequential Machines Siivas Devadas

  20. Evidence Regarding the Internal Structure: Confirmatory Factor Analysis

    ERIC Educational Resources Information Center

    Lewis, Todd F.

    2017-01-01

    American Educational Research Association (AERA) standards stipulate that researchers show evidence of the internal structure of instruments. Confirmatory factor analysis (CFA) is one structural equation modeling procedure designed to assess construct validity of assessments that has broad applicability for counselors interested in instrument…

  1. Procedures for numerical analysis of circadian rhythms

    PubMed Central

    REFINETTI, ROBERTO; LISSEN, GERMAINE CORNÉ; HALBERG, FRANZ

    2010-01-01

    This article reviews various procedures used in the analysis of circadian rhythms at the populational, organismal, cellular and molecular levels. The procedures range from visual inspection of time plots and actograms to several mathematical methods of time series analysis. Computational steps are described in some detail, and additional bibliographic resources and computer programs are listed. PMID:23710111

  2. Risk factors for early cytologic abnormalities after loop electrosurgical excision procedure.

    PubMed

    Dietrich, Charles S; Yancey, Michael K; Miyazawa, Kunio; Williams, David L; Farley, John

    2002-02-01

    To evaluate risk factors for early cytologic abnormalities and recurrent cervical dysplasia after loop electrosurgical excision procedure (LEEP). A retrospective analysis was performed of all pathology records for LEEPs performed at our institution from January 1996 through July 1998. Follow-up cytology from 2 through 12 months after LEEP was reviewed. Patients with abnormal cytology were referred for further colposcopic evaluation. Statistical analysis using chi2 test for trend, proportional hazards model test, Fisher exact tests, and life table analysis were performed to identify risk factors for early cytologic abnormalities after LEEP and to determine relative risk of recurrent dysplasia. A total of 298 women underwent LEEP during the study period, and 29% of these had cytologic abnormalities after LEEP. Grade of dysplasia, ectocervical marginal status, endocervical marginal status, and glandular involvement with dysplasia were not found to be independent risk factors for early cytologic abnormalities. However, when risk factors were analyzed cumulatively, the abnormal cytology rate increased from 24% with no risk factors to 67% with three risk factors present (P =.037). Of patients with abnormal cytology after LEEP, 40% developed subsequent dysplasia, and the mean time to diagnosis was approximately 6 months. The relative risk of subsequent dysplasia ranged from a 20% increase to twice the risk if post-LEEP cytology was low-grade squamous intraepithelial lesion or high-grade squamous intraepithelial lesion, respectively. Based on these results, consideration should be given for early colposcopic examination of patients who have evidence of marginal involvement or endocervical glandular involvement with dysplasia. These patients are at increased risk for abnormal cytology and recurrent dysplasia. This initial visit should occur at 6 months, as the mean time to recurrence of dysplasia was 6.5 months.

  3. A procedure for landslide susceptibility zonation by the conditional analysis method1

    NASA Astrophysics Data System (ADS)

    Clerici, Aldo; Perego, Susanna; Tellini, Claudio; Vescovi, Paolo

    2002-12-01

    Numerous methods have been proposed for landslide probability zonation of the landscape by means of a Geographic Information System (GIS). Among the multivariate methods, i.e. those methods which simultaneously take into account all the factors contributing to instability, the Conditional Analysis method applied to a subdivision of the territory into Unique Condition Units is particularly straightforward from a conceptual point of view and particularly suited to the use of a GIS. In fact, working on the principle that future landslides are more likely to occur under those conditions which led to past instability, landslide susceptibility is defined by computing the landslide density in correspondence with different combinations of instability factors. The conceptual simplicity of this method, however, does not necessarily imply that it is simple to implement, especially as it requires rather complex operations and a high number of GIS commands. Moreover, there is the possibility that, in order to achieve satisfactory results, the procedure has to be repeated a few times changing the factors or modifying the class subdivision. To solve this problem, we created a shell program which, by combining the shell commands, the GIS Geographical Research Analysis Support System (GRASS) commands and the gawk language commands, carries out the whole procedure automatically. This makes the construction of a Landslide Susceptibility Map easy and fast for large areas too, and even when a high spatial resolution is adopted, as shown by application of the procedure to the Parma River basin, in the Italian Northern Apennines.

  4. Updating QR factorization procedure for solution of linear least squares problem with equality constraints.

    PubMed

    Zeb, Salman; Yousaf, Muhammad

    2017-01-01

    In this article, we present a QR updating procedure as a solution approach for linear least squares problem with equality constraints. We reduce the constrained problem to unconstrained linear least squares and partition it into a small subproblem. The QR factorization of the subproblem is calculated and then we apply updating techniques to its upper triangular factor R to obtain its solution. We carry out the error analysis of the proposed algorithm to show that it is backward stable. We also illustrate the implementation and accuracy of the proposed algorithm by providing some numerical experiments with particular emphasis on dense problems.

  5. A Primer on Bootstrap Factor Analysis as Applied to Health Studies Research

    ERIC Educational Resources Information Center

    Lu, Wenhua; Miao, Jingang; McKyer, E. Lisako J.

    2014-01-01

    Objectives: To demonstrate how the bootstrap method could be conducted in exploratory factor analysis (EFA) with a syntax written in SPSS. Methods: The data obtained from the Texas Childhood Obesity Prevention Policy Evaluation project (T-COPPE project) were used for illustration. A 5-step procedure to conduct bootstrap factor analysis (BFA) was…

  6. Structural Analysis of Correlated Factors: Lessons from the Verbal-Performance Dichotomy of the Wechsler Scales.

    ERIC Educational Resources Information Center

    Macmann, Gregg M.; Barnett, David W.

    1994-01-01

    Describes exploratory and confirmatory analyses of verbal-performance procedures to illustrate concepts and procedures for analysis of correlated factors. Argues that, based on convergent and discriminant validity criteria, factors should have higher correlations with variables that they purport to measure than with other variables. Discusses…

  7. Learning the facts in medical school is not enough: which factors predict successful application of procedural knowledge in a laboratory setting?

    PubMed Central

    2013-01-01

    Background Medical knowledge encompasses both conceptual (facts or “what” information) and procedural knowledge (“how” and “why” information). Conceptual knowledge is known to be an essential prerequisite for clinical problem solving. Primarily, medical students learn from textbooks and often struggle with the process of applying their conceptual knowledge to clinical problems. Recent studies address the question of how to foster the acquisition of procedural knowledge and its application in medical education. However, little is known about the factors which predict performance in procedural knowledge tasks. Which additional factors of the learner predict performance in procedural knowledge? Methods Domain specific conceptual knowledge (facts) in clinical nephrology was provided to 80 medical students (3rd to 5th year) using electronic flashcards in a laboratory setting. Learner characteristics were obtained by questionnaires. Procedural knowledge in clinical nephrology was assessed by key feature problems (KFP) and problem solving tasks (PST) reflecting strategic and conditional knowledge, respectively. Results Results in procedural knowledge tests (KFP and PST) correlated significantly with each other. In univariate analysis, performance in procedural knowledge (sum of KFP+PST) was significantly correlated with the results in (1) the conceptual knowledge test (CKT), (2) the intended future career as hospital based doctor, (3) the duration of clinical clerkships, and (4) the results in the written German National Medical Examination Part I on preclinical subjects (NME-I). After multiple regression analysis only clinical clerkship experience and NME-I performance remained independent influencing factors. Conclusions Performance in procedural knowledge tests seems independent from the degree of domain specific conceptual knowledge above a certain level. Procedural knowledge may be fostered by clinical experience. More attention should be paid to the

  8. Learning the facts in medical school is not enough: which factors predict successful application of procedural knowledge in a laboratory setting?

    PubMed

    Schmidmaier, Ralf; Eiber, Stephan; Ebersbach, Rene; Schiller, Miriam; Hege, Inga; Holzer, Matthias; Fischer, Martin R

    2013-02-22

    Medical knowledge encompasses both conceptual (facts or "what" information) and procedural knowledge ("how" and "why" information). Conceptual knowledge is known to be an essential prerequisite for clinical problem solving. Primarily, medical students learn from textbooks and often struggle with the process of applying their conceptual knowledge to clinical problems. Recent studies address the question of how to foster the acquisition of procedural knowledge and its application in medical education. However, little is known about the factors which predict performance in procedural knowledge tasks. Which additional factors of the learner predict performance in procedural knowledge? Domain specific conceptual knowledge (facts) in clinical nephrology was provided to 80 medical students (3rd to 5th year) using electronic flashcards in a laboratory setting. Learner characteristics were obtained by questionnaires. Procedural knowledge in clinical nephrology was assessed by key feature problems (KFP) and problem solving tasks (PST) reflecting strategic and conditional knowledge, respectively. Results in procedural knowledge tests (KFP and PST) correlated significantly with each other. In univariate analysis, performance in procedural knowledge (sum of KFP+PST) was significantly correlated with the results in (1) the conceptual knowledge test (CKT), (2) the intended future career as hospital based doctor, (3) the duration of clinical clerkships, and (4) the results in the written German National Medical Examination Part I on preclinical subjects (NME-I). After multiple regression analysis only clinical clerkship experience and NME-I performance remained independent influencing factors. Performance in procedural knowledge tests seems independent from the degree of domain specific conceptual knowledge above a certain level. Procedural knowledge may be fostered by clinical experience. More attention should be paid to the interplay of individual clinical clerkship experiences

  9. Factors affecting job satisfaction in nurse faculty: a meta-analysis.

    PubMed

    Gormley, Denise K

    2003-04-01

    Evidence in the literature suggests job satisfaction can make a difference in keeping qualified workers on the job, but little research has been conducted focusing specifically on nursing faculty. Several studies have examined nurse faculty satisfaction in relationship to one or two influencing factors. These factors include professional autonomy, leader role expectations, organizational climate, perceived role conflict and role ambiguity, leadership behaviors, and organizational characteristics. This meta-analysis attempts to synthesize the various studies conducted on job satisfaction in nursing faculty and analyze which influencing factors have the greatest effect. The procedure used for this meta-analysis consisted of reviewing studies to identify factors influencing job satisfaction, research questions, sample size reported, instruments used for measurement of job satisfaction and influencing factors, and results of statistical analysis.

  10. Numerical procedure to determine geometric view factors for surfaces occluded by cylinders

    NASA Technical Reports Server (NTRS)

    Sawyer, P. L.

    1978-01-01

    A numerical procedure was developed to determine geometric view factors between connected infinite strips occluded by any number of infinite circular cylinders. The procedure requires a two-dimensional cross-sectional model of the configuration of interest. The two-dimensional model consists of a convex polygon enclosing any number of circles. Each side of the polygon represents one strip, and each circle represents a circular cylinder. A description and listing of a computer program based on this procedure are included in this report. The program calculates geometric view factors between individual strips and between individual strips and the collection of occluding cylinders.

  11. Confirmatory factor analysis using Microsoft Excel.

    PubMed

    Miles, Jeremy N V

    2005-11-01

    This article presents a method for using Microsoft (MS) Excel for confirmatory factor analysis (CFA). CFA is often seen as an impenetrable technique, and thus, when it is taught, there is frequently little explanation of the mechanisms or underlying calculations. The aim of this article is to demonstrate that this is not the case; it is relatively straightforward to produce a spreadsheet in MS Excel that can carry out simple CFA. It is possible, with few or no programming skills, to effectively program a CFA analysis and, thus, to gain insight into the workings of the procedure.

  12. Risk factors and serological markers of liver cirrhosis after Fontan procedure.

    PubMed

    Shimizu, Mikiko; Miyamoto, Kenji; Nishihara, Yunosuke; Izumi, Gaku; Sakai, Shuji; Inai, Kei; Nishikawa, Toshio; Nakanishi, Toshio

    2016-09-01

    Liver cirrhosis (LC), which may result in hepatic failure or cancer, has been reported in patients after Fontan procedure. The purpose of this study was to clarify the frequency and histological characteristics of LC, and to evaluate the risk factors and serological markers of LC with Fontan circulation. Retrospective review of contrast-enhanced CT scans (CT) of the liver was carried out in 57 patients after Fontan procedure. Patients were divided into two groups: LC group (n = 31) and no LC group (n = 26). Age at Fontan procedure, duration after Fontan procedure, catheterization data, and history of failing Fontan circulation were compared between groups. Serological data including γ-GTP and hyaluronic acid were compared. Histology of autopsy specimens was assessed when available. Duration after Fontan procedure was significantly longer in LC group than no LC group. History of failing Fontan circulation was more frequent in LC group than in no LC group. There was no correlation between type of procedure (APC/Bjork/lateral tunnel/TCPC) and LC in this series. Serum hyaluronic acid, γ-GTP, and Forns index were significantly higher in LC group. Significant risk factors for LC were duration after Fontan procedure (>20 years). In autopsy specimens, histopathological changes of LC were observed predominantly in the central venous area. LC diagnosed with CT is frequent in patients long after Fontan procedure, especially after 20 years. Hyaluronic acid and γ-GTP could be useful markers to monitor the progression of liver fibrosis in Fontan patients.

  13. Text mining factor analysis (TFA) in green tea patent data

    NASA Astrophysics Data System (ADS)

    Rahmawati, Sela; Suprijadi, Jadi; Zulhanif

    2017-03-01

    Factor analysis has become one of the most widely used multivariate statistical procedures in applied research endeavors across a multitude of domains. There are two main types of analyses based on factor analysis: Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA). Both EFA and CFA aim to observed relationships among a group of indicators with a latent variable, but they differ fundamentally, a priori and restrictions made to the factor model. This method will be applied to patent data technology sector green tea to determine the development technology of green tea in the world. Patent analysis is useful in identifying the future technological trends in a specific field of technology. Database patent are obtained from agency European Patent Organization (EPO). In this paper, CFA model will be applied to the nominal data, which obtain from the presence absence matrix. While doing processing, analysis CFA for nominal data analysis was based on Tetrachoric matrix. Meanwhile, EFA model will be applied on a title from sector technology dominant. Title will be pre-processing first using text mining analysis.

  14. Human Factors Analysis of Pipeline Monitoring and Control Operations: Final Technical Report

    DOT National Transportation Integrated Search

    2008-11-26

    The purpose of the Human Factors Analysis of Pipeline Monitoring and Control Operations project was to develop procedures that could be used by liquid pipeline operators to assess and manage the human factors risks in their control rooms that may adv...

  15. 40 CFR 246.201-7 - Recommended procedures: Cost analysis.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Recommended procedures: Cost analysis... § 246.201-7 Recommended procedures: Cost analysis. After potential markets have been located (but prior... residual solid waste have been established, an analysis should be conducted which compares the costs of the...

  16. 40 CFR 246.202-6 - Recommended procedures: Cost analysis.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Recommended procedures: Cost analysis... § 246.202-6 Recommended procedures: Cost analysis. After potential markets have been identified (but... residual solid waste have been established, an analysis should be conducted which compares the costs of the...

  17. 40 CFR 246.200-8 - Recommended procedures: Cost analysis.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Recommended procedures: Cost analysis... § 246.200-8 Recommended procedures: Cost analysis. After potential markets have been located (but prior... paper and residual solid waste have been established, an analysis should be conducted which compares the...

  18. Multicriteria decision analysis in ranking of analytical procedures for aldrin determination in water.

    PubMed

    Tobiszewski, Marek; Orłowski, Aleksander

    2015-03-27

    The study presents the possibility of multi-criteria decision analysis (MCDA) application when choosing analytical procedures with low environmental impact. A type of MCDA, Preference Ranking Organization Method for Enrichment Evaluations (PROMETHEE), was chosen as versatile tool that meets all the analytical chemists--decision makers requirements. Twenty five analytical procedures for aldrin determination in water samples (as an example) were selected as input alternatives to MCDA analysis. Nine different criteria describing the alternatives were chosen from different groups--metrological, economical and the most importantly--environmental impact. The weights for each criterion were obtained from questionnaires that were sent to experts, giving three different scenarios for MCDA results. The results of analysis show that PROMETHEE is very promising tool to choose the analytical procedure with respect to its greenness. The rankings for all three scenarios placed solid phase microextraction and liquid phase microextraction--based procedures high, while liquid-liquid extraction, solid phase extraction and stir bar sorptive extraction--based procedures were placed low in the ranking. The results show that although some of the experts do not intentionally choose green analytical chemistry procedures, their MCDA choice is in accordance with green chemistry principles. The PROMETHEE ranking results were compared with more widely accepted green analytical chemistry tools--NEMI and Eco-Scale. As PROMETHEE involved more different factors than NEMI, the assessment results were only weakly correlated. Oppositely, the results of Eco-Scale assessment were well-correlated as both methodologies involved similar criteria of assessment. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Using P-Stat, BMDP and SPSS for a cross-products factor analysis.

    PubMed

    Tanner, B A; Leiman, J M

    1983-06-01

    The major disadvantage of the Q factor analysis with Euclidean distances described by Tanner and Koning [Comput. Progr. Biomed. 12 (1980) 201-202] is the considerable editing required. An alternative procedure with commercially distributed software, and with cross-products in place of Euclidean distances is described. This procedure does not require any editing.

  20. NASA trend analysis procedures

    NASA Technical Reports Server (NTRS)

    1993-01-01

    This publication is primarily intended for use by NASA personnel engaged in managing or implementing trend analysis programs. 'Trend analysis' refers to the observation of current activity in the context of the past in order to infer the expected level of future activity. NASA trend analysis was divided into 5 categories: problem, performance, supportability, programmatic, and reliability. Problem trend analysis uncovers multiple occurrences of historical hardware or software problems or failures in order to focus future corrective action. Performance trend analysis observes changing levels of real-time or historical flight vehicle performance parameters such as temperatures, pressures, and flow rates as compared to specification or 'safe' limits. Supportability trend analysis assesses the adequacy of the spaceflight logistics system; example indicators are repair-turn-around time and parts stockage levels. Programmatic trend analysis uses quantitative indicators to evaluate the 'health' of NASA programs of all types. Finally, reliability trend analysis attempts to evaluate the growth of system reliability based on a decreasing rate of occurrence of hardware problems over time. Procedures for conducting all five types of trend analysis are provided in this publication, prepared through the joint efforts of the NASA Trend Analysis Working Group.

  1. Preterm delivery risk factors in singletons born after in vitro fertilization procedures.

    PubMed

    Ban Frangez, Helena; Korosec, Sara; Verdenik, Ivan; Kotar, Vanja; Kladnik, Urska; Vrtacnik Bokal, Eda

    2014-05-01

    Women delivering singletons after in vitro fertilization (IVF) procedures have a greater risk of preterm delivery (PD). The aim of our study was to analyze PD risk factors and to identify those that could possibly be prevented. In our matched controlled study we analyzed 1127 singleton deliveries after IVF and transfer of fresh embryos performed at the University Medical Center Ljubljana between 1 January 2002 and 31 December 2010. For every delivery included in the study group we chose three consecutive controls matched by maternal age, parity and maternity hospital. The main outcome measure was PD (<37 weeks). Investigated variables were: previous PD (PPD), conization, pregestational diabetes mellitus, uterine anomaly, operation on the uterus, chronic renal disease, maternal age and parity, and body mass index (BMI). Variables investigated within the IVF group were: stimulation protocol, laboratory procedure, number of retrieved oocytes and number and quality of transferred embryos. The PD rate after IVF was 1.5 times higher than after natural conception (11.5% in the IVF group and 7.7% in the control group, p<0.001). Conization and chronic renal disease were shown to be significant risk factors for PD in both the IVF group and the naturally conceiving controls. BMI>30 was an important risk factor only in the IVF group (OR 1.86 (1.06-3.27) vs. 1.10 (0.67-1.80)) and PPD only in the controls (OR 1.83 (0.78-4.28) vs. 3.22 (1.55-6.67)). Among the investigated PD risk factors, an IVF procedure was shown to be the fifth most important one. On analyzing parameters of the ovarian stimulation and IVF procedure, no PD risk factor was identified. IVF was shown to be a significant risk factor for PD. In the IVF population, BMI plays a far more important role in PD than in the fertile population. In our research PD reoccurrence in IVF group was less than expected, which could perhaps be explained by the surgical correction of gynecological pathology and, where necessary, its

  2. Human Factors and ISS Medical Systems: Highlights of Procedures and Equipment Findings

    NASA Technical Reports Server (NTRS)

    Byrne, V. E.; Hudy, C.; Smith, D.; Whitmore, M.

    2005-01-01

    As part of the Space Human Factors Engineering Critical Questions Roadmap, a three year Technology Development Project (TDP) was funded by NASA Headquarters to examine emergency medical procedures on ISS. The overall aim of the emergency medical procedures project was to determine the human factors issues in the procedures, training, communications and equipment, and to recommend solutions that will improve the survival rate of crewmembers in the event of a medical emergency. Currently, each ISS crew remains on orbit for six month intervals. As there is not standing requirement for a physician crewmember, during such time, the maintenance of crew health is dependant on individual crewmembers. Further, in the event of an emergency, crew will need to provide prolonged maintenance care, as well as emergency treatment, to an injured crewmember while awaiting transport to Earth. In addition to the isolation of the crew, medical procedures must be carried out within the further limitations imposed by the physical environment of the space station. For example, in order to administer care on ISS without the benefit of gravity, the Crew Medical Officers (CMOs) must restrain the equipment required to perform the task, restrain the injured crewmember, and finally, restrain themselves. Both the physical environment and the physical space available further limit the technology that can be used onboard. Equipment must be compact, yet able to withstand high levels of radiation and function without gravity. The focus here is to highlight the human factors impacts from our three year project involving the procedures and equipment areas that have been investigated and provided valuable to ISS and provide groundwork for human factors requirements for medical applications for exploration missions.

  3. Quantitative analysis of crystalline pharmaceuticals in powders and tablets by a pattern-fitting procedure using X-ray powder diffraction data.

    PubMed

    Yamamura, S; Momose, Y

    2001-01-16

    A pattern-fitting procedure for quantitative analysis of crystalline pharmaceuticals in solid dosage forms using X-ray powder diffraction data is described. This method is based on a procedure for pattern-fitting in crystal structure refinement, and observed X-ray scattering intensities were fitted to analytical expressions including some fitting parameters, i.e. scale factor, peak positions, peak widths and degree of preferred orientation of the crystallites. All fitting parameters were optimized by the non-linear least-squares procedure. Then the weight fraction of each component was determined from the optimized scale factors. In the present study, well-crystallized binary systems, zinc oxide-zinc sulfide (ZnO-ZnS) and salicylic acid-benzoic acid (SA-BA), were used as the samples. In analysis of the ZnO-ZnS system, the weight fraction of ZnO or ZnS could be determined quantitatively in the range of 5-95% in the case of both powders and tablets. In analysis of the SA-BA systems, the weight fraction of SA or BA could be determined quantitatively in the range of 20-80% in the case of both powders and tablets. Quantitative analysis applying this pattern-fitting procedure showed better reproducibility than other X-ray methods based on the linear or integral intensities of particular diffraction peaks. Analysis using this pattern-fitting procedure also has the advantage that the preferred orientation of the crystallites in solid dosage forms can be also determined in the course of quantitative analysis.

  4. Randomization Procedures Applied to Analysis of Ballistic Data

    DTIC Science & Technology

    1991-06-01

    test,;;15. NUMBER OF PAGES data analysis; computationally intensive statistics ; randomization tests; permutation tests; 16 nonparametric statistics ...be 0.13. 8 Any reasonable statistical procedure would fail to support the notion of improvement of dynamic over standard indexing based on this data ...AD-A238 389 TECHNICAL REPORT BRL-TR-3245 iBRL RANDOMIZATION PROCEDURES APPLIED TO ANALYSIS OF BALLISTIC DATA MALCOLM S. TAYLOR BARRY A. BODT - JUNE

  5. Terrain Analysis Procedural Guide for Railroads (Report Number 10 in the ETL Series on Guides for Army Terrain Analysis).

    DTIC Science & Technology

    1982-12-01

    study was conducted under DA Project 4A762707A855, Task C, Work 6 Unit 21, "Military Geographic Analysis Technology." This study was done under the...supplement to the Terrain Analysis Procedural Guide for Roads and Related Structures (ETL-0205, October 1979). In sparsely inhabited study areas, railroad data... study area. " W, In general, three major sources of information are available that will = be helpful in the production of factor overlays for railroads

  6. Perioperative outcomes for pediatric neurosurgical procedures: analysis of the National Surgical Quality Improvement Program-Pediatrics.

    PubMed

    Kuo, Benjamin J; Vissoci, Joao Ricardo N; Egger, Joseph R; Smith, Emily R; Grant, Gerald A; Haglund, Michael M; Rice, Henry E

    2017-03-01

    OBJECTIVE Existing studies have shown a high overall rate of adverse events (AEs) following pediatric neurosurgical procedures. However, little is known regarding the morbidity of specific procedures or the association with risk factors to help guide quality improvement (QI) initiatives. The goal of this study was to describe the 30-day mortality and AE rates for pediatric neurosurgical procedures by using the American College of Surgeons (ACS) National Surgical Quality Improvement Program-Pediatrics (NSQIP-Peds) database platform. METHODS Data on 9996 pediatric neurosurgical patients were acquired from the 2012-2014 NSQIP-Peds participant user file. Neurosurgical cases were analyzed by the NSQIP-Peds targeted procedure categories, including craniotomy/craniectomy, defect repair, laminectomy, shunts, and implants. The primary outcome measure was 30-day mortality, with secondary outcomes including individual AEs, composite morbidity (all AEs excluding mortality and unplanned reoperation), surgical-site infection, and unplanned reoperation. Univariate analysis was performed between individual AEs and patient characteristics using Fischer's exact test. Associations between individual AEs and continuous variables (duration from admission to operation, work relative value unit, and operation time) were examined using the Student t-test. Patient characteristics and continuous variables associated with any AE by univariate analysis were used to develop category-specific multivariable models through backward stepwise logistic regression. RESULTS The authors analyzed 3383 craniotomy/craniectomy, 242 defect repair, 1811 laminectomy, and 4560 shunt and implant cases and found a composite overall morbidity of 30.2%, 38.8%, 10.2%, and 10.7%, respectively. Unplanned reoperation rates were highest for defect repair (29.8%). The mortality rate ranged from 0.1% to 1.2%. Preoperative ventilator dependence was a significant predictor of any AE for all procedure groups, whereas

  7. Detailed Analysis of Peri-Procedural Strokes in Patients Undergoing Intracranial Stenting in SAMMPRIS

    PubMed Central

    Fiorella, David; Derdeyn, Colin P; Lynn, Michael J; Barnwell, Stanley L; Hoh, Brian L.; Levy, Elad I.; Harrigan, Mark R.; Klucznik, Richard P.; McDougall, Cameron G.; Pride, G. Lee; Zaidat, Osama O.; Lutsep, Helmi L.; Waters, Michael F.; Hourihane, J. Maurice; Alexandrov, Andrei V.; Chiu, David; Clark, Joni M.; Johnson, Mark D.; Torbey, Michel T.; Rumboldt, Zoran; Cloft, Harry J.; Turan, Tanya N.; Lane, Bethany F.; Janis, L. Scott; Chimowitz, Marc I.

    2012-01-01

    Background and Purpose Enrollment in the SAMMPRIS trial was halted due to the high risk of stroke or death within 30 days of enrollment in the percutaneous transluminal angioplasty and stenting (PTAS) arm relative to the medical arm. This analysis focuses on the patient and procedural factors that may have been associated with peri-procedural cerebrovascular events in the trial. Methods Bivariate and multivariate analyses were performed to evaluate whether patient and procedural variables were associated with cerebral ischemic or hemorrhagic events occurring within 30 days of enrollment (termed peri-procedural) in the PTAS arm. Results Of 224 patients randomized to PTAS, 213 underwent angioplasty alone (n=5) or with stenting (n=208). Of these, 13 had hemorrhagic strokes (7 parenchymal, 6 subarachnoid), 19 had ischemic stroke, and 2 had cerebral infarcts with temporary signs (CITS) within the peri-procedural period. Ischemic events were categorized as perforator occlusions (13), embolic (4), mixed perforator and embolic (2), and delayed stent occlusion (2). Multivariate analyses showed that higher percent stenosis, lower modified Rankin score, and clopidogrel load associated with an activated clotting time above the target range were associated (p ≤ 0.05) with hemorrhagic stroke. Non-smoking, basilar artery stenosis, diabetes, and older age were associated (p ≤ 0.05) with ischemic events. Conclusions Peri-procedural strokes in SAMMPRIS had multiple causes with the most common being perforator occlusion. Although risk factors for peri-procedural strokes could be identified, excluding patients with these features from undergoing PTAS to lower the procedural risk would limit PTAS to a small subset of patients. Moreover, given the small number of events, the present data should be used for hypothesis generation rather than to guide patient selection in clinical practice. PMID:22984008

  8. 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.

  9. A Study of Item Bias for Attitudinal Measurement Using Maximum Likelihood Factor Analysis.

    ERIC Educational Resources Information Center

    Mayberry, Paul W.

    A technique for detecting item bias that is responsive to attitudinal measurement considerations is a maximum likelihood factor analysis procedure comparing multivariate factor structures across various subpopulations, often referred to as SIFASP. The SIFASP technique allows for factorial model comparisons in the testing of various hypotheses…

  10. Factors that influence length of stay for in-patient gynaecology surgery: is the Case Mix Group (CMG) or type of procedure more important?

    PubMed

    Carey, Mark S; Victory, Rahi; Stitt, Larry; Tsang, Nicole

    2006-02-01

    To compare the association between the Case Mix Group (CMG) code and length of stay (LOS) with the association between the type of procedure and LOS in patients admitted for gynaecology surgery. We examined the records of women admitted for surgery in CMG 579 (major uterine/adnexal procedure, no malignancy) or 577 (major surgery ovary/adnexa with malignancy) between April 1997 and March 1999. Factors thought to influence LOS included age, weight, American Society of Anesthesiologists (ASA) score, physician, day of the week on which surgery was performed, and procedure type. Procedures were divided into six categories, four for CMG 579 and two for CMG 577. Data were abstracted from the hospital information costing system (T2 system) and by retrospective chart review. Multivariable analysis was performed using linear regression with backwards elimination. There were 606 patients in CMG 579 and 101 patients in CMG 577, and the corresponding median LOS was four days (range 1-19) for CMG 579 and nine days (range 3-30) for CMG 577. Combined analysis of both CMGs 577 and 579 revealed the following factors as highly significant determinants of LOS: procedure, age, physician, and ASA score. Although confounded by procedure type, the CMG did not significantly account for differences in LOS in the model if procedure was considered. Pairwise comparisons of procedure categories were all found to be statistically significant, even when controlled for other important variables. The type of procedure better accounts for differences in LOS by describing six statistically distinct procedure groups rather than the traditional two CMGs. It is reasonable therefore to consider changing the current CMG codes for gynaecology to a classification based on the type of procedure.

  11. Incidence and Risk Factors for Perioperative Cardiovascular and Respiratory Adverse Events in Pediatric Patients With Congenital Heart Disease Undergoing Noncardiac Procedures.

    PubMed

    Lee, Sandra; Reddington, Elise; Koutsogiannaki, Sophia; Hernandez, Michael R; Odegard, Kirsten C; DiNardo, James A; Yuki, Koichi

    2018-04-27

    While mortality and adverse perioperative events after noncardiac surgery in children with a broad range of congenital cardiac lesions have been investigated using large multiinstitutional databases, to date single-center studies addressing adverse outcomes in children with congenital heart disease (CHD) undergoing noncardiac surgery have only included small numbers of patients with significant heart disease. The primary objective of this study was to determine the incidences of perioperative cardiovascular and respiratory events in a large cohort of patients from a single institution with a broad range of congenital cardiac lesions undergoing noncardiac procedures and to determine risk factors for these events. We identified 3010 CHD patients presenting for noncardiac procedures in our institution over a 5-year period. We collected demographic information, including procedure performed, cardiac diagnosis, ventricular function as assessed by echocardiogram within 6 months of the procedure, and classification of CHD into 3 groups (minor, major, or severe CHD) based on residual lesion burden and cardiovascular functional status. Characteristics related to conduct of anesthesia care were also collected. The primary outcome variables for our analysis were the incidences of intraoperative cardiovascular and respiratory events. Univariable and multivariable logistic regressions were used to determine risk factors for these 2 outcomes. The incidence of cardiovascular events was 11.5% and of respiratory events was 4.7%. Univariate analysis and multivariable analysis demonstrated that American Society of Anesthesiologists (≥3), emergency cases, major and severe CHD, single-ventricle physiology, ventricular dysfunction, orthopedic surgery, general surgery, neurosurgery, and pulmonary procedures were associated with perioperative cardiovascular events. Respiratory events were associated with American Society of Anesthesiologists (≥4) and otolaryngology, gastrointestinal

  12. 76 FR 78015 - Revised Analysis and Mapping Procedures for Non-Accredited Levees

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-15

    ...] Revised Analysis and Mapping Procedures for Non-Accredited Levees AGENCY: Federal Emergency Management... comments on the proposed solution for Revised Analysis and Mapping Procedures for Non-Accredited Levees. This document proposes a revised procedure for the analysis and mapping of non-accredited levees on...

  13. Exploratory Bifactor Analysis of the WJ-III Cognitive in Adulthood via the Schmid-Leiman Procedure

    ERIC Educational Resources Information Center

    Dombrowski, Stefan C.

    2014-01-01

    The Woodcock-Johnson-III cognitive in the adult time period (age 20 to 90 plus) was analyzed using exploratory bifactor analysis via the Schmid-Leiman orthogonalization procedure. The results of this study suggested possible overfactoring, a different factor structure from that posited in the Technical Manual and a lack of invariance across both…

  14. Cement Leakage in Percutaneous Vertebral Augmentation for Osteoporotic Vertebral Compression Fractures: Analysis of Risk Factors.

    PubMed

    Xie, Weixing; Jin, Daxiang; Ma, Hui; Ding, Jinyong; Xu, Jixi; Zhang, Shuncong; Liang, De

    2016-05-01

    The risk factors for cement leakage were retrospectively reviewed in 192 patients who underwent percutaneous vertebral augmentation (PVA). To discuss the factors related to the cement leakage in PVA procedure for the treatment of osteoporotic vertebral compression fractures. PVA is widely applied for the treatment of osteoporotic vertebral fractures. Cement leakage is a major complication of this procedure. The risk factors for cement leakage were controversial. A retrospective review of 192 patients who underwent PVA was conducted. The following data were recorded: age, sex, bone density, number of fractured vertebrae before surgery, number of treated vertebrae, severity of the treated vertebrae, operative approach, volume of injected bone cement, preoperative vertebral compression ratio, preoperative local kyphosis angle, intraosseous clefts, preoperative vertebral cortical bone defect, and ratio and type of cement leakage. To study the correlation between each factor and cement leakage ratio, bivariate regression analysis was employed to perform univariate analysis, whereas multivariate linear regression analysis was employed to perform multivariate analysis. The study included 192 patients (282 treated vertebrae), and cement leakage occurred in 100 vertebrae (35.46%). The vertebrae with preoperative cortical bone defects generally exhibited higher cement leakage ratio, and the leakage is typically type C. Vertebrae with intact cortical bones before the procedure tend to experience type S leakage. Univariate analysis showed that patient age, bone density, number of fractured vertebrae before surgery, and vertebral cortical bone were associated with cement leakage ratio (P<0.05). Multivariate analysis showed that the main factors influencing bone cement leakage are bone density and vertebral cortical bone defect, with standardized partial regression coefficients of -0.085 and 0.144, respectively. High bone density and vertebral cortical bone defect are

  15. Risk factors for hospital morbidity and mortality after the Norwood procedure: A report from the Pediatric Heart Network Single Ventricle Reconstruction trial.

    PubMed

    Tabbutt, Sarah; Ghanayem, Nancy; Ravishankar, Chitra; Sleeper, Lynn A; Cooper, David S; Frank, Deborah U; Lu, Minmin; Pizarro, Christian; Frommelt, Peter; Goldberg, Caren S; Graham, Eric M; Krawczeski, Catherine Dent; Lai, Wyman W; Lewis, Alan; Kirsh, Joel A; Mahony, Lynn; Ohye, Richard G; Simsic, Janet; Lodge, Andrew J; Spurrier, Ellen; Stylianou, Mario; Laussen, Peter

    2012-10-01

    We sought to identify risk factors for mortality and morbidity during the Norwood hospitalization in newborn infants with hypoplastic left heart syndrome and other single right ventricle anomalies enrolled in the Single Ventricle Reconstruction trial. Potential predictors for outcome included patient- and procedure-related variables and center volume and surgeon volume. Outcome variables occurring during the Norwood procedure and before hospital discharge or stage II procedure included mortality, end-organ complications, length of ventilation, and hospital length of stay. Univariate and multivariable Cox regression analyses were performed with bootstrapping to estimate reliability for mortality. Analysis included 549 subjects prospectively enrolled from 15 centers; 30-day and hospital mortality were 11.5% (63/549) and 16.0% (88/549), respectively. Independent risk factors for both 30-day and hospital mortality included lower birth weight, genetic abnormality, extracorporeal membrane oxygenation (ECMO) and open sternum on the day of the Norwood procedure. In addition, longer duration of deep hypothermic circulatory arrest was a risk factor for 30-day mortality. Shunt type at the end of the Norwood procedure was not a significant risk factor for 30-day or hospital mortality. Independent risk factors for postoperative renal failure (n = 46), sepsis (n = 93), increased length of ventilation, and hospital length of stay among survivors included genetic abnormality, lower center/surgeon volume, open sternum, and post-Norwood operations. Innate patient factors, ECMO, open sternum, and lower center/surgeon volume are important risk factors for postoperative mortality and/or morbidity during the Norwood hospitalization. Copyright © 2012 The American Association for Thoracic Surgery. Published by Mosby, Inc. All rights reserved.

  16. A procedure to estimate proximate analysis of mixed organic wastes.

    PubMed

    Zaher, U; Buffiere, P; Steyer, J P; Chen, S

    2009-04-01

    In waste materials, proximate analysis measuring the total concentration of carbohydrate, protein, and lipid contents from solid wastes is challenging, as a result of the heterogeneous and solid nature of wastes. This paper presents a new procedure that was developed to estimate such complex chemical composition of the waste using conventional practical measurements, such as chemical oxygen demand (COD) and total organic carbon. The procedure is based on mass balance of macronutrient elements (carbon, hydrogen, nitrogen, oxygen, and phosphorus [CHNOP]) (i.e., elemental continuity), in addition to the balance of COD and charge intensity that are applied in mathematical modeling of biological processes. Knowing the composition of such a complex substrate is crucial to study solid waste anaerobic degradation. The procedure was formulated to generate the detailed input required for the International Water Association (London, United Kingdom) Anaerobic Digestion Model number 1 (IWA-ADM1). The complex particulate composition estimated by the procedure was validated with several types of food wastes and animal manures. To make proximate analysis feasible for validation, the wastes were classified into 19 types to allow accurate extraction and proximate analysis. The estimated carbohydrates, proteins, lipids, and inerts concentrations were highly correlated to the proximate analysis; correlation coefficients were 0.94, 0.88, 0.99, and 0.96, respectively. For most of the wastes, carbohydrate was the highest fraction and was estimated accurately by the procedure over an extended range with high linearity. For wastes that are rich in protein and fiber, the procedure was even more consistent compared with the proximate analysis. The new procedure can be used for waste characterization in solid waste treatment design and optimization.

  17. Generalized Appended Product Indicator Procedure for Nonlinear Structural Equation Analysis.

    ERIC Educational Resources Information Center

    Wall, Melanie M.; Amemiya, Yasuo

    2001-01-01

    Considers the estimation of polynomial structural models and shows a limitation of an existing method. Introduces a new procedure, the generalized appended product indicator procedure, for nonlinear structural equation analysis. Addresses statistical issues associated with the procedure through simulation. (SLD)

  18. Efficacy and safety of recombinant activated factor vii in major surgical procedures: systematic review and meta-analysis of randomized clinical trials.

    PubMed

    Ranucci, Marco; Isgrò, Giuseppe; Soro, Giorgio; Conti, Daniela; De Toffol, Barbara

    2008-03-01

    To investigate the efficacy and safety of recombinant activated factor VII (rFVIIa) treatment in patients undergoing major surgical procedures. Relevant studies were searched in BioMedCentral, CENTRAL, PubMed, and PubMed Central. Only randomized controlled trials on humans undergoing major surgery were included. Efficacy was determined as the rate of patients receiving allogeneic packed red blood cells; safety was assessed in terms of thromboembolic complications and mortality rate. We followed the Cochrane Collaboration method for data extraction and internal validity procedures, as well as the Quality of Reporting of Meta-analyses statement. Seven randomized controlled trials met the inclusion criteria. Treatment with rFVIIa is associated with a reduced risk of receiving allogeneic packed red blood cells (odds ratio, 0.29; 95% confidence interval, 0.10-0.80). In a subgroup analysis, only patients receiving at least 50 mug/kg of rFVIIa had a significant benefit (odds ratio, 0.43; 95% confidence interval, 0.23-0.78). No differences in thromboembolic complications and mortality rates were observed. Treatment with rFVIIa is effective in reducing the rate of patients undergoing transfusion with allogeneic packed red blood cells. However, the cost-benefit ratio is favorable only in patients who need a huge number of packed red blood cell units. No safety concerns arise from the present study.

  19. Systematic Review: Predisposing, Precipitating, Perpetuating, and Present Factors Predicting Anticipatory Distress to Painful Medical Procedures in Children

    PubMed Central

    Pillai Riddell, Rebecca R.; Khan, Maria; Calic, Masa; Taddio, Anna; Tablon, Paula

    2016-01-01

    Objective To conduct a systematic review of the factors predicting anticipatory distress to painful medical procedures in children. Methods A systematic search was conducted to identify studies with factors related to anticipatory distress to painful medical procedures in children aged 0–18 years. The search retrieved 7,088 articles to review against inclusion criteria. A total of 77 studies were included in the review. Results 31 factors were found to predict anticipatory distress to painful medical procedures in children. A narrative synthesis of the evidence was conducted, and a summary figure is presented. Conclusions Many factors were elucidated that contribute to the occurrence of anticipatory distress to painful medical procedures. The factors that appear to increase anticipatory distress are child psychopathology, difficult child temperament, parent distress promoting behaviors, parent situational distress, previous pain events, parent anticipation of distress, and parent anxious predisposition. Longitudinal and experimental research is needed to further elucidate these factors. PMID:26338981

  20. Ranking procedure for partial discriminant analysis

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

    Beckman, R.J.; Johnson, M.E.

    1981-09-01

    A rank procedure developed by Broffitt, Randles, and Hogg (1976) is modified to control the conditional probability of misclassification given that classification has been attempted. This modification leads to a useful solution to the two-population partial discriminant analysis problem for even moderately sized training sets.

  1. A GIS-based automated procedure for landslide susceptibility mapping by the Conditional Analysis method: the Baganza valley case study (Italian Northern Apennines)

    NASA Astrophysics Data System (ADS)

    Clerici, Aldo; Perego, Susanna; Tellini, Claudio; Vescovi, Paolo

    2006-08-01

    Among the many GIS based multivariate statistical methods for landslide susceptibility zonation, the so called “Conditional Analysis method” holds a special place for its conceptual simplicity. In fact, in this method landslide susceptibility is simply expressed as landslide density in correspondence with different combinations of instability-factor classes. To overcome the operational complexity connected to the long, tedious and error prone sequence of commands required by the procedure, a shell script mainly based on the GRASS GIS was created. The script, starting from a landslide inventory map and a number of factor maps, automatically carries out the whole procedure resulting in the construction of a map with five landslide susceptibility classes. A validation procedure allows to assess the reliability of the resulting model, while the simple mean deviation of the density values in the factor class combinations, helps to evaluate the goodness of landslide density distribution. The procedure was applied to a relatively small basin (167 km2) in the Italian Northern Apennines considering three landslide types, namely rotational slides, flows and complex landslides, for a total of 1,137 landslides, and five factors, namely lithology, slope angle and aspect, elevation and slope/bedding relations. The analysis of the resulting 31 different models obtained combining the five factors, confirms the role of lithology, slope angle and slope/bedding relations in influencing slope stability.

  2. Human Factors Process Task Analysis: Liquid Oxygen Pump Acceptance Test Procedure at the Advanced Technology Development Center

    NASA Technical Reports Server (NTRS)

    Diorio, Kimberly A.; Voska, Ned (Technical Monitor)

    2002-01-01

    This viewgraph presentation provides information on Human Factors Process Failure Modes and Effects Analysis (HF PFMEA). HF PFMEA includes the following 10 steps: Describe mission; Define System; Identify human-machine; List human actions; Identify potential errors; Identify factors that effect error; Determine likelihood of error; Determine potential effects of errors; Evaluate risk; Generate solutions (manage error). The presentation also describes how this analysis was applied to a liquid oxygen pump acceptance test.

  3. 46 CFR 4.06-50 - Specimen analysis and follow-up procedures.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... to develop all relevant information and to produce a complete analysis report. (b) Reports shall be... 46 Shipping 1 2011-10-01 2011-10-01 false Specimen analysis and follow-up procedures. 4.06-50... Involving Vessels in Commercial Service § 4.06-50 Specimen analysis and follow-up procedures. (a) Each...

  4. 46 CFR 4.06-50 - Specimen analysis and follow-up procedures.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... to develop all relevant information and to produce a complete analysis report. (b) Reports shall be... 46 Shipping 1 2012-10-01 2012-10-01 false Specimen analysis and follow-up procedures. 4.06-50... Involving Vessels in Commercial Service § 4.06-50 Specimen analysis and follow-up procedures. (a) Each...

  5. Systematic Review: Predisposing, Precipitating, Perpetuating, and Present Factors Predicting Anticipatory Distress to Painful Medical Procedures in Children.

    PubMed

    Racine, Nicole M; Riddell, Rebecca R Pillai; Khan, Maria; Calic, Masa; Taddio, Anna; Tablon, Paula

    2016-03-01

    To conduct a systematic review of the factors predicting anticipatory distress to painful medical procedures in children. A systematic search was conducted to identify studies with factors related to anticipatory distress to painful medical procedures in children aged 0-18 years. The search retrieved 7,088 articles to review against inclusion criteria. A total of 77 studies were included in the review. 31 factors were found to predict anticipatory distress to painful medical procedures in children. A narrative synthesis of the evidence was conducted, and a summary figure is presented. Many factors were elucidated that contribute to the occurrence of anticipatory distress to painful medical procedures. The factors that appear to increase anticipatory distress are child psychopathology, difficult child temperament, parent distress promoting behaviors, parent situational distress, previous pain events, parent anticipation of distress, and parent anxious predisposition. Longitudinal and experimental research is needed to further elucidate these factors. © The Author 2015. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  6. Procedural-support music therapy in the healthcare setting: a cost-effectiveness analysis.

    PubMed

    DeLoach Walworth, Darcy

    2005-08-01

    This comparative analysis examined the cost-effectiveness of music therapy as a procedural support in the pediatric healthcare setting. Many healthcare organizations are actively attempting to reduce the amount of sedation for pediatric patients undergoing various procedures. Patients receiving music therapy-assisted computerized tomography scans ( n = 57), echocardiograms ( n = 92), and other procedures ( n = 17) were included in the analysis. Results of music therapy-assisted procedures indicate successful elimination of patient sedation, reduction in procedural times, and decrease in the number of staff members present for procedures. Implications for nurses and music therapists in the healthcare setting are discussed.

  7. A Quantitative Review of Functional Analysis Procedures in Public School Settings

    ERIC Educational Resources Information Center

    Solnick, Mark D.; Ardoin, Scott P.

    2010-01-01

    Functional behavioral assessments can consist of indirect, descriptive and experimental procedures, such as a functional analysis. Although the research contains numerous examples demonstrating the effectiveness of functional analysis procedures, experimental conditions are often difficult to implement in classroom settings and analog conditions…

  8. Sensitivity of the diagnostic radiological index of protection to procedural factors in fluoroscopy.

    PubMed

    Jones, A Kyle; Pasciak, Alexander S; Wagner, Louis K

    2016-07-01

    To evaluate the sensitivity of the diagnostic radiological index of protection (DRIP), used to quantify the protective value of radioprotective garments, to procedural factors in fluoroscopy in an effort to determine an appropriate set of scatter-mimicking primary beams to be used in measuring the DRIP. Monte Carlo simulations were performed to determine the shape of the scattered x-ray spectra incident on the operator in different clinical fluoroscopy scenarios, including interventional radiology and interventional cardiology (IC). Two clinical simulations studied the sensitivity of the scattered spectrum to gantry angle and patient size, while technical factors were varied according to measured automatic dose rate control (ADRC) data. Factorial simulations studied the sensitivity of the scattered spectrum to gantry angle, field of view, patient size, and beam quality for constant technical factors. Average energy (Eavg) was the figure of merit used to condense fluence in each energy bin to a single numerical index. Beam quality had the strongest influence on the scattered spectrum in fluoroscopy. Many procedural factors affect the scattered spectrum indirectly through their effect on primary beam quality through ADRC, e.g., gantry angle and patient size. Lateral C-arm rotation, common in IC, increased the energy of the scattered spectrum, regardless of the direction of rotation. The effect of patient size on scattered radiation depended on ADRC characteristics, patient size, and procedure type. The scattered spectrum striking the operator in fluoroscopy is most strongly influenced by primary beam quality, particularly kV. Use cases for protective garments should be classified by typical procedural primary beam qualities, which are governed by the ADRC according to the impacts of patient size, anatomical location, and gantry angle.

  9. Microalgae Compositional Analysis Laboratory Procedures | Bioenergy | NREL

    Science.gov Websites

    these methods build on years of research in algal biomass analysis. By combining the appropriate LAPs and Ash in Algal Biomass This procedure describes the methods used to determine the amount of moisture

  10. 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…

  11. Incidence and Risk Factors for Major Hematomas in Aesthetic Surgery: Analysis of 129,007 Patients.

    PubMed

    Kaoutzanis, Christodoulos; Winocour, Julian; Gupta, Varun; Ganesh Kumar, Nishant; Sarosiek, Konrad; Wormer, Blair; Tokin, Christopher; Grotting, James C; Higdon, K Kye

    2017-10-16

    Postoperative hematomas are one of the most frequent complications following aesthetic surgery. Identifying risk factors for hematoma has been limited by underpowered studies from single institution experiences. To examine the incidence and identify independent risk factors for postoperative hematomas following cosmetic surgery utilizing a prospective, multicenter database. A prospectively enrolled cohort of patients who underwent aesthetic surgery between 2008 and 2013 was identified from the CosmetAssure database. Primary outcome was occurrence of major hematomas requiring emergency room visit, hospital admission, or reoperation within 30 days of the index operation. Univariate and multivariate analysis was used to identify potential risk factors for hematomas including age, gender, body mass index (BMI), smoking, diabetes, type of surgical facility, procedure by body region, and combined procedures. Of 129,007 patients, 1180 (0.91%) had a major hematoma. Mean age (42.0 ± 13.0 years vs 40.9 ± 13.9 years, P < 0.01) and BMI (24.5 ± 5.0 kg/m2 vs 24.3 ± 4.6 kg/m2, P < 0.01) were higher in patients with hematomas. Males suffered more hematomas than females (1.4% vs 0.9%, P < 0.01). Hematoma rates were higher in patients undergoing combined procedures compared to single procedures (1.1% vs 0.8%, P < 0.01), and breast procedures compared to body/extremity or face procedures (1.0% vs 0.8% vs 0.7%, P < 0.01). On multivariate analysis, independent predictors of hematoma included age (Relative Risk [RR] 1.01), male gender (RR 1.98), the procedure being performed in a hospital setting rather than an office-based setting (RR 1.68), combined procedures (RR 1.35), and breast procedures rather than the body/extremity and face procedures (RR 1.81). Major hematoma is the most common complication following aesthetic surgery. Male patients and those undergoing breast or combined procedures have a significantly higher risk of developing hematomas. 2. © 2017 The American Society

  12. Factors Associated with Increased Rates of Post-procedural Stroke or Death following Carotid Artery Stent Placement: A Systematic Review.

    PubMed Central

    Khan, Muhib; Qureshi, Adnan I

    2014-01-01

    Background and Purpose We provide an assessment of clinical, angiographic, and procedure related risk factors associated with stroke and/or death in patients undergoing carotid artery stent placement which will assist in patient stratification and identification of high-stent risk patients. Methods A comprehensive search of Medline from January 1st 1996 to December 31st 2011 was performed with key words “carotid artery stenosis”, “ carotid artery stenting”, “carotid artery stent placement”, “death” , ” mortality”, “stroke”, “outcome”, “clinical predictors”, “angiographic predictors”, was performed in various combinations. We independently abstracted data and assessed the quality of the studies. This analysis led to the selection of 71 articles for review. Results Clinical factors including age≥80 years, symptomatic status, procedure within 2 weeks of symptoms, chronic renal failure, diabetes mellitus, and hemispheric TIA were associated with stroke (ischemic or hemorrhagic) and death within 1 month after carotid artery stent placement. Angiographic factors including left carotid artery intervention, stenosis > 90%, ulcerated and calcified plaques, lesion length > 10mm, thrombus at the site, ostial involvement, predilation without EPD, ICA-CCA angulation > 60%, aortic arch type III, and aortic arch calcification were also associated with 1 month stroke and/or death. Intra-procedural platelet GP IIb/IIIa inhibitors, protamine use, multiple stents, predilatation prior to stent placement were associated with stroke (ischemic or hemorrhagic) and death after carotid artery stent placement. Intraprocedural use of embolic protection devices and stent design (open versus closed cell design) did not demonstrate a consistent relationship with 1 month stroke and/or death. Procedural statin use, and operator and center experience of more than 50 procedures per year were protective for 1 month stroke and/or death. Conclusions Our review

  13. An Improved Qualitative Analysis Procedure for Aluminum Subgroup Cations.

    ERIC Educational Resources Information Center

    Kistner, C. R.; Robinson, Patricia J.

    1983-01-01

    Describes a procedure for the qualitative analysis of aluminum subgroup cations designed to avoid failure to obtain lead or barium chromate precipitates or failure to report aluminum hydroxide when present (due to staining). Provides a flow chart and step-by-step explanation for the new procedure, indicating significantly improved student results.…

  14. Human Factors Analysis to Improve the Processing of Ares-1 Launch Vehicle

    NASA Technical Reports Server (NTRS)

    Dippolito, Gregory M.; Stambolian, Damon B.

    2011-01-01

    The Constellation Program (CxP) is composed of an array of vehicles used to go to the Moon and Mars. The Ares vehicle one of the components of CxP, goes through several stages of processing before it is launched at the Kennedy Space Center. In order to have efficient and effective ground processing inside and outside the vehicle, all of the ground processing activities should be analyzed. The analysis for this program was performed, by engineers, technicians, and human factors experts with spacecraft processing experience. The procedure used to gather data was accomplished by observing human activities within physical mockups. The paper will focus on the procedures, analysis and results from these observations.

  15. Risk factors for unplanned readmission within 30 days after pediatric neurosurgery: a nationwide analysis of 9799 procedures from the American College of Surgeons National Surgical Quality Improvement Program

    PubMed Central

    Sherrod, Brandon A.; Johnston, James M.; Rocque, Brandon G.

    2017-01-01

    Objective Readmission rate is increasingly used as a quality outcome measure after surgery. The purpose of this study was to establish, using a national database, the baseline readmission rates and risk factors for readmission after pediatric neurosurgical procedures. Methods The American College of Surgeons National Surgical Quality Improvement Program–Pediatric database was queried for pediatric patients treated by a neurosurgeon from 2012 to 2013. Procedures were categorized by current procedural terminology code. Patient demographics, comorbidities, preoperative laboratory values, operative variables, and postoperative complications were analyzed via univariate and multivariate techniques to find associations with unplanned readmission within 30 days of the primary procedure. Results A total of 9799 cases met the inclusion criteria, 1098 (11.2%) of which had an unplanned readmission within 30 days. Readmission occurred 14.0 ± 7.7 days postoperatively (mean ± standard deviation). The 4 procedures with the highest unplanned readmission rates were CSF shunt revision (17.3%), repair of myelomeningocele > 5 cm in diameter (15.4%), CSF shunt creation (14.1%), and craniectomy for infratentorial tumor excision (13.9%). Spine (6.5%), craniotomy for craniosynostosis (2.1%), and skin lesion (1.0%) procedures had the lowest unplanned readmission rates. On multivariate regression analysis, the odds of readmission were greatest in patients experiencing postoperative surgical site infection (SSI; deep, organ/space, superficial SSI and wound disruption: OR > 12 and p < 0.001 for each). Postoperative pneumonia (OR 4.294, p < 0.001), urinary tract infection (OR 4.262, p < 0.001), and sepsis (OR 2.616, p = 0.006) also independently increased the readmission risk. Independent patient risk factors for unplanned readmission included Native American race (OR 2.363, p = 0.019), steroid use > 10 days (OR 1.411, p = 0.010), oxygen supplementation (OR 1.645, p = 0.010), nutritional

  16. Risk factors for unplanned readmission within 30 days after pediatric neurosurgery: a nationwide analysis of 9799 procedures from the American College of Surgeons National Surgical Quality Improvement Program.

    PubMed

    Sherrod, Brandon A; Johnston, James M; Rocque, Brandon G

    2016-09-01

    OBJECTIVE Hospital readmission rate is increasingly used as a quality outcome measure after surgery. The purpose of this study was to establish, using a national database, the baseline readmission rates and risk factors for patient readmission after pediatric neurosurgical procedures. METHODS The American College of Surgeons National Surgical Quality Improvement Program-Pediatric database was queried for pediatric patients treated by a neurosurgeon between 2012 and 2013. Procedures were categorized by current procedural terminology (CPT) code. Patient demographics, comorbidities, preoperative laboratory values, operative variables, and postoperative complications were analyzed via univariate and multivariate techniques to find associations with unplanned readmissions within 30 days of the primary procedure. RESULTS A total of 9799 cases met the inclusion criteria, 1098 (11.2%) of which had an unplanned readmission within 30 days. Readmission occurred 14.0 ± 7.7 days postoperatively (mean ± standard deviation). The 4 procedures with the highest unplanned readmission rates were CSF shunt revision (17.3%; CPT codes 62225 and 62230), repair of myelomeningocele > 5 cm in diameter (15.4%), CSF shunt creation (14.1%), and craniectomy for infratentorial tumor excision (13.9%). The lowest unplanned readmission rates were for spine (6.5%), craniotomy for craniosynostosis (2.1%), and skin lesion (1.0%) procedures. On multivariate regression analysis, the odds of readmission were greatest in patients experiencing postoperative surgical site infection (SSI; deep, organ/space, superficial SSI, and wound disruption: OR > 12 and p < 0.001 for each). Postoperative pneumonia (OR 4.294, p < 0.001), urinary tract infection (OR 4.262, p < 0.001), and sepsis (OR 2.616, p = 0.006) also independently increased the readmission risk. Independent patient risk factors for unplanned readmission included Native American race (OR 2.363, p = 0.019), steroid use > 10 days (OR 1.411, p = 0

  17. A Comparison of Measurement Equivalence Methods Based on Confirmatory Factor Analysis and Item Response Theory.

    ERIC Educational Resources Information Center

    Flowers, Claudia P.; Raju, Nambury S.; Oshima, T. C.

    Current interest in the assessment of measurement equivalence emphasizes two methods of analysis, linear, and nonlinear procedures. This study simulated data using the graded response model to examine the performance of linear (confirmatory factor analysis or CFA) and nonlinear (item-response-theory-based differential item function or IRT-Based…

  18. Procedure for Failure Mode, Effects, and Criticality Analysis (FMECA)

    NASA Technical Reports Server (NTRS)

    1966-01-01

    This document provides guidelines for the accomplishment of Failure Mode, Effects, and Criticality Analysis (FMECA) on the Apollo program. It is a procedure for analysis of hardware items to determine those items contributing most to system unreliability and crew safety problems.

  19. Formalizing the Austrian Procedure Catalogue: A 4-step methodological analysis approach.

    PubMed

    Neururer, Sabrina Barbara; Lasierra, Nelia; Peiffer, Karl Peter; Fensel, Dieter

    2016-04-01

    Due to the lack of an internationally accepted and adopted standard for coding health interventions, Austria has established its own country-specific procedure classification system - the Austrian Procedure Catalogue (APC). Even though the APC is an elaborate coding standard for medical procedures, it has shortcomings that limit its usability. In order to enhance usability and usefulness, especially for research purposes and e-health applications, we developed an ontologized version of the APC. In this paper we present a novel four-step approach for the ontology engineering process, which enables accurate extraction of relevant concepts for medical ontologies from written text. The proposed approach for formalizing the APC consists of the following four steps: (1) comparative pre-analysis, (2) definition analysis, (3) typological analysis, and (4) ontology implementation. The first step contained a comparison of the APC to other well-established or elaborate health intervention coding systems in order to identify strengths and weaknesses of the APC. In the second step, a list of definitions of medical terminology used in the APC was obtained. This list of definitions was used as input for Step 3, in which we identified the most important concepts to describe medical procedures using the qualitative typological analysis approach. The definition analysis as well as the typological analysis are well-known and effective methods used in social sciences, but not commonly employed in the computer science or ontology engineering domain. Finally, this list of concepts was used in Step 4 to formalize the APC. The pre-analysis highlighted the major shortcomings of the APC, such as the lack of formal definition, leading to implicitly available, but not directly accessible information (hidden data), or the poor procedural type classification. After performing the definition and subsequent typological analyses, we were able to identify the following main characteristics of

  20. 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…

  1. Task analysis method for procedural training curriculum development.

    PubMed

    Riggle, Jakeb D; Wadman, Michael C; McCrory, Bernadette; Lowndes, Bethany R; Heald, Elizabeth A; Carstens, Patricia K; Hallbeck, M Susan

    2014-06-01

    A central venous catheter (CVC) is an important medical tool used in critical care and emergent situations. Integral to proper care in many circumstances, insertion of a CVC introduces the risk of central line-associated blood stream infections and mechanical adverse events; proper training is important for safe CVC insertion. Cognitive task analysis (CTA) methods have been successfully implemented in the medical field to improve the training of postgraduate medical trainees, but can be very time-consuming to complete and require a significant time commitment from many subject matter experts (SMEs). Many medical procedures such as CVC insertion are linear processes with well-documented procedural steps. These linear procedures may not require a traditional CTA to gather the information necessary to create a training curriculum. Accordingly, a novel, streamlined CTA method designed primarily to collect cognitive cues for linear procedures was developed to be used by medical professionals with minimal CTA training. This new CTA methodology required fewer trained personnel, fewer interview sessions, and less time commitment from SMEs than a traditional CTA. Based on this study, a streamlined CTA methodology can be used to efficiently gather cognitive information on linear medical procedures for the creation of resident training curricula and procedural skills assessments.

  2. Effective Work Procedure design Using Discomfort and Effort Factor in Brick stacking operation-A case study

    NASA Astrophysics Data System (ADS)

    Rout, Biswaranjan; Dash, R. R.; Dhupal, D.

    2018-02-01

    In this work a typical planning of movement of limbs and torso of the worker to be well design to reduce fatigue and energy of the worker. A simulation model is generated to suit the procedure and comply with the constraints in the workspace. It requires verifying the capability of human postures and movements in different working conditions for the evaluation of effectiveness of the new design. In this article a simple human performance measure is introduce that enable the mathematical model for evaluation of a cost function. The basic scheme is to evaluate the performance in the form of several cost factors using AI techniques. Here two main cost factors taken in to consideration are discomfort factor and effort factor in limb movements. Discomfort factor measures the level of discomfort from the most neutral position of a given limb to the position of the corresponding limb after movement and effort factor is a measure of the displacement of the corresponding limbs from the original position. The basic aim is to optimize the movement of the limbs with the above mentioned cost functions. The effectiveness of the procedure is tested with an example of working procedure of workers used for stacking of fly ash bricks in a local fly ash bricks manufacturing unit. The objective is to find out the optimised movement of the limbs to reduce discomfort level and effort required of workers. The effectiveness of the procedure in this case study illustrated with the obtained results.

  3. Cost analysis of robotic versus laparoscopic general surgery procedures.

    PubMed

    Higgins, Rana M; Frelich, Matthew J; Bosler, Matthew E; Gould, Jon C

    2017-01-01

    Robotic surgical systems have been used at a rapidly increasing rate in general surgery. Many of these procedures have been performed laparoscopically for years. In a surgical encounter, a significant portion of the total costs is associated with consumable supplies. Our hospital system has invested in a software program that can track the costs of consumable surgical supplies. We sought to determine the differences in cost of consumables with elective laparoscopic and robotic procedures for our health care organization. De-identified procedural cost and equipment utilization data were collected from the Surgical Profitability Compass Procedure Cost Manager System (The Advisory Board Company, Washington, DC) for our health care system for laparoscopic and robotic cholecystectomy, fundoplication, and inguinal hernia between the years 2013 and 2015. Outcomes were length of stay, case duration, and supply cost. Statistical analysis was performed using a t-test for continuous variables, and statistical significance was defined as p < 0.05. The total cost of consumable surgical supplies was significantly greater for all robotic procedures. Length of stay did not differ for fundoplication or cholecystectomy. Length of stay was greater for robotic inguinal hernia repair. Case duration was similar for cholecystectomy (84.3 robotic and 75.5 min laparoscopic, p = 0.08), but significantly longer for robotic fundoplication (197.2 robotic and 162.1 min laparoscopic, p = 0.01) and inguinal hernia repair (124.0 robotic and 84.4 min laparoscopic, p = ≪0.01). We found a significantly increased cost of general surgery procedures for our health care system when cases commonly performed laparoscopically are instead performed robotically. Our analysis is limited by the fact that we only included costs associated with consumable surgical supplies. The initial acquisition cost (over $1 million for robotic surgical system), depreciation, and service contract for the robotic

  4. Consequences of Decontamination Procedures in Forensic Hair Analysis Using Metal-Assisted Secondary Ion Mass Spectrometry Analysis.

    PubMed

    Cuypers, Eva; Flinders, Bryn; Boone, Carolien M; Bosman, Ingrid J; Lusthof, Klaas J; Van Asten, Arian C; Tytgat, Jan; Heeren, Ron M A

    2016-03-15

    Today, hair testing is considered to be the standard method for the detection of chronic drug abuse. Nevertheless, the differentiation between systemic exposure and external contamination remains a major challenge in the forensic interpretation of hair analysis. Nowadays, it is still impossible to directly show the difference between external contamination and use-related incorporation. Although the effects of washing procedures on the distribution of (incorporated) drugs in hair remain unknown, these decontamination procedures prior to hair analysis are considered to be indispensable in order to exclude external contamination. However, insights into the effect of decontamination protocols on levels and distribution of drugs incorporated in hair are essential to draw the correct forensic conclusions from hair analysis; we studied the consequences of these procedures on the spatial distribution of cocaine in hair using imaging mass spectrometry. Additionally, using metal-assisted secondary ion mass spectrometry, we are the first to directly show the difference between cocaine-contaminated and user hair without any prior washing procedure.

  5. Monte Carlo investigation of backscatter factors for skin dose determination in interventional neuroradiology procedures

    NASA Astrophysics Data System (ADS)

    Omar, Artur; Benmakhlouf, Hamza; Marteinsdottir, Maria; Bujila, Robert; Nowik, Patrik; Andreo, Pedro

    2014-03-01

    Complex interventional and diagnostic x-ray angiographic (XA) procedures may yield patient skin doses exceeding the threshold for radiation induced skin injuries. Skin dose is conventionally determined by converting the incident air kerma free-in-air into entrance surface air kerma, a process that requires the use of backscatter factors. Subsequently, the entrance surface air kerma is converted into skin kerma using mass energy-absorption coefficient ratios tissue-to-air, which for the photon energies used in XA is identical to the skin dose. The purpose of this work was to investigate how the cranial bone affects backscatter factors for the dosimetry of interventional neuroradiology procedures. The PENELOPE Monte Carlo system was used to calculate backscatter factors at the entrance surface of a spherical and a cubic water phantom that includes a cranial bone layer. The simulations were performed for different clinical x-ray spectra, field sizes, and thicknesses of the bone layer. The results show a reduction of up to 15% when a cranial bone layer is included in the simulations, compared with conventional backscatter factors calculated for a homogeneous water phantom. The reduction increases for thicker bone layers, softer incident beam qualities, and larger field sizes, indicating that, due to the increased photoelectric crosssection of cranial bone compared to water, the bone layer acts primarily as an absorber of low-energy photons. For neurointerventional radiology procedures, backscatter factors calculated at the entrance surface of a water phantom containing a cranial bone layer increase the accuracy of the skin dose determination.

  6. Empirical analysis of domestic medical travel for elective cardiovascular procedures.

    PubMed

    Langley, Jacob D; Johnson, Tricia J; Hohmann, Samuel F; Meurer, Steve J; Garman, Andy N

    2013-10-01

    To investigate whether domestic medical travel (DMT; traveling outside of one's home region but within the United States for medical care) and surgeon volume affect clinical outcomes and costs for patients undergoing elective cardiovascular procedures. Retrospective, cross-sectional analysis of patient discharge data from US academic medical centers. Patients were classified as medical travelers if they received elective, nonemergent care more than 250 miles from home. High-volume surgeons (HVSs) were those above the 75th percentile compared with other study surgeons in the annual number of cardiovascular surgeries performed. Multivariable regression models were fit to test the relationships among complications, mortality, length of stay (LOS), cost, DMT status, and surgeon volume, controlling for sociodemographic and clinical factors. Patients who traveled to HVSs were more likely to be male, white, have lower severity of illness, and have health insurance through an indemnity plan or preferred provider organization with coverage outside of the patient's home region. Patients who traveled to HVSs had shorter LOS and fewer complications than those who received care from local, low-volume surgeons. There was no significant difference in mortality between travelers and nontravelers. Patients who travelled to HVSs for elective cardiovascular procedures had outcomes similar to or better than those of patients who received care locally from low-volume surgeons. We found no increase in complications or LOS, despite potentially complex logistical arrangements required by travelers. More work is needed to evaluate the potential of DMT to improve the value of care provided for selected procedures.

  7. Biomass Compositional Analysis Laboratory Procedures | Bioenergy | NREL

    Science.gov Websites

    Compositional Analysis This procedure describes methods for sample drying and size reduction, obtaining samples methods used to determine the amount of solids or moisture present in a solid or slurry biomass sample as values? We have found that neutral detergent fiber (NDF) and acid detergent fiber (ADF) methods report

  8. Chemical factor analysis of skin cancer FTIR-FEW spectroscopic data

    NASA Astrophysics Data System (ADS)

    Bruch, Reinhard F.; Sukuta, Sydney

    2002-03-01

    Chemical Factor Analysis (CFA) algorithms were applied to transform complex Fourier transform infrared fiberoptical evanescent wave (FTIR-FEW) normal and malignant skin tissue spectra into factor spaces for analysis and classification. The factor space approach classified melanoma beyond prior pathological classifications related to specific biochemical alterations to health states in cluster diagrams allowing diagnosis with more biochemical specificity, resolving biochemical component spectra and employing health state eigenvector angular configurations as disease state sensors. This study demonstrated a wealth of new information from in vivo FTIR-FEW spectral tissue data, without extensive a priori information or clinically invasive procedures. In particular, we employed a variety of methods used in CFA to select the rank of spectroscopic data sets of normal benign and cancerous skin tissue. We used the Malinowski indicator function (IND), significance level and F-Tests to rank our data matrices. Normal skin tissue, melanoma and benign tumors were modeled by four, two and seven principal abstract factors, respectively. We also showed that the spectrum of the first eigenvalue was equivalent to the mean spectrum. The graphical depiction of angular disparities between the first abstract factors can be adopted as a new way to characterize and diagnose melanoma cancer.

  9. Discriminatory Analysis II. Factor Analysis and Discrimination

    DTIC Science & Technology

    1950-10-01

    present In a given-’test. The last phase of factor ana2lysis is concerned -- -kv’-~ ’psyc Ig hological-siLr ifi-cance to the rectors, extract -, aed*-hee...tests. However, as IHotelling t s procedu~re is an iterative ~ one,.it can be stopped after the extraction of’ any nuLmber of coiuponenta if., one -deems...need not extract 22 ’l p factors and that one can factior R1 by this method as well as R, However, the fact remains that the coomrponents do not have

  10. Cost of bariatric surgery and factors associated with increased cost: an analysis of national inpatient sample.

    PubMed

    Khorgami, Zhamak; Aminian, Ali; Shoar, Saeed; Andalib, Amin; Saber, Alan A; Schauer, Philip R; Brethauer, Stacy A; Sclabas, Guido M

    2017-08-01

    In the current healthcare environment, bariatric surgery centers need to be cost-effective while maintaining quality. The aim of this study was to evaluate national cost of bariatric surgery to identify the factors associated with a higher cost. A retrospective analysis of 2012-2013 Healthcare Cost and Utilization Project - Nationwide Inpatient Sample (HCUP-NIS). We included all patients with a diagnosis of morbid obesity (ICD9 278.01) and a Diagnosis Related Group code related to procedures for obesity, who underwent Roux-en-Y gastric bypass (RYGB), sleeve gastrectomy (SG), or adjustable gastric banding (AGB) as their primary procedure. We converted "hospital charges" to "cost," using hospital specific cost-to-charge ratio. Inflation was adjusted using the annual consumer price index. Increased cost was defined as the top 20th percentile of the expenditure and its associated factors were analyzed using the logistic regression multivariate analysis. A total of 45,219 patients (20,966 RYGBs, 22,380 SGs, and 1,873 AGBs) were included. The median (interquartile range) calculated costs for RYGB, SG, and AGB were $12,543 ($9,970-$15,857), $10,531 ($8,248-$13,527), and $9,219 ($7,545-$12,106), respectively (P<.001). Robotic-assisted procedures had the highest impact on the cost (odds ratio 3.6, 95% confidence interval 3.2-4). Hospital cost of RYGB and SG increased linearly with the length of hospital stay and almost doubled after 7 days. Furthermore, multivariate analysis showed that certain co-morbidities and concurrent procedures were associated with an increased cost. Factors contributing to the cost variation of bariatric procedures include co-morbidities, robotic platform, complexity of surgery, and hospital length of stay. Copyright © 2017 American Society for Bariatric Surgery. Published by Elsevier Inc. All rights reserved.

  11. Analysis of Factors Associated With Rhytidectomy Malpractice Litigation Cases.

    PubMed

    Kandinov, Aron; Mutchnick, Sean; Nangia, Vaibhuv; Svider, Peter F; Zuliani, Giancarlo F; Shkoukani, Mahdi A; Carron, Michael A

    2017-07-01

    This study investigates the financial burden of medical malpractice litigation associated with rhytidectomies, as well as factors that contribute to litigation and poor defendant outcomes, which can help guide physician practices. To comprehensively evaluate rhytidectomy malpractice litigation. Jury verdict and settlement reports related to rhytidectomy malpractice litigations were obtained using the Westlaw Next database. Use of medical malpractice in conjunction with several terms for rhytidectomy, to account for the various procedure names associated with the procedure, yielded 155 court cases. Duplicate and nonrelevant cases were removed, and 89 cases were included in the analysis and reviewed for outcomes, defendant specialty, payments, and other allegations raised in proceedings. Data were collected from November 21, 2015, to December 25, 2015. Data analysis took place from December 25, 2015, to January 20, 2016. A total of 89 cases met our inclusion criteria. Most plaintiffs were female (81 of 88 with known sex [92%]), and patient age ranged from 40 to 76 years (median age, 56 years). Fifty-three (60%) were resolved in the defendant's favor, while the remaining 36 cases (40%) were resolved with either a settlement or a plaintiff verdict payment. The mean payment was $1.4 million. A greater proportion of cases involving plastic surgeon defendants were resolved with payment compared with cases involving defendants with ear, nose, and throat specialty (15 [36%] vs 4 [24%]). The most common allegations raised in litigation were intraoperative negligence (61 [69%]), poor cosmesis or disfigurement (57 [64%]), inadequate informed consent (30 [34%]), additional procedures required (14 [16%]), postoperative negligence (12 [14%]), and facial nerve injury (10 [11%]). Six cases (7%) involved alleged negligence surrounding a "lifestyle-lift" procedure, which tightens or oversews the superficial muscular aponeurosis system layer. In this study, although most cases of

  12. Quantitative analysis of crystalline pharmaceuticals in tablets by pattern-fitting procedure using X-ray diffraction pattern.

    PubMed

    Takehira, Rieko; Momose, Yasunori; Yamamura, Shigeo

    2010-10-15

    A pattern-fitting procedure using an X-ray diffraction pattern was applied to the quantitative analysis of binary system of crystalline pharmaceuticals in tablets. Orthorhombic crystals of isoniazid (INH) and mannitol (MAN) were used for the analysis. Tablets were prepared under various compression pressures using a direct compression method with various compositions of INH and MAN. Assuming that X-ray diffraction pattern of INH-MAN system consists of diffraction intensities from respective crystals, observed diffraction intensities were fitted to analytic expression based on X-ray diffraction theory and separated into two intensities from INH and MAN crystals by a nonlinear least-squares procedure. After separation, the contents of INH were determined by using the optimized normalization constants for INH and MAN. The correction parameter including all the factors that are beyond experimental control was required for quantitative analysis without calibration curve. The pattern-fitting procedure made it possible to determine crystalline phases in the range of 10-90% (w/w) of the INH contents. Further, certain characteristics of the crystals in the tablets, such as the preferred orientation, size of crystallite, and lattice disorder were determined simultaneously. This method can be adopted to analyze compounds whose crystal structures are known. It is a potentially powerful tool for the quantitative phase analysis and characterization of crystals in tablets and powders using X-ray diffraction patterns. Copyright 2010 Elsevier B.V. All rights reserved.

  13. Element-by-element Solution Procedures for Nonlinear Structural Analysis

    NASA Technical Reports Server (NTRS)

    Hughes, T. J. R.; Winget, J. M.; Levit, I.

    1984-01-01

    Element-by-element approximate factorization procedures are proposed for solving the large finite element equation systems which arise in nonlinear structural mechanics. Architectural and data base advantages of the present algorithms over traditional direct elimination schemes are noted. Results of calculations suggest considerable potential for the methods described.

  14. The use of cognitive task analysis to improve instructional descriptions of procedures.

    PubMed

    Clark, Richard E; Pugh, Carla M; Yates, Kenneth A; Inaba, Kenji; Green, Donald J; Sullivan, Maura E

    2012-03-01

    Surgical training relies heavily on the ability of expert surgeons to provide complete and accurate descriptions of a complex procedure. However, research from a variety of domains suggests that experts often omit critical information about the judgments, analysis, and decisions they make when solving a difficult problem or performing a complex task. In this study, we compared three methods for capturing surgeons' descriptions of how to perform the procedure for inserting a femoral artery shunt (unaided free-recall, unaided free-recall with simulation, and cognitive task analysis methods) to determine which method produced more accurate and complete results. Cognitive task analysis was approximately 70% more complete and accurate than free-recall and or free-recall during a simulation of the procedure. Ten expert trauma surgeons at a major urban trauma center were interviewed separately and asked to describe how to perform an emergency shunt procedure. Four surgeons provided an unaided free-recall description of the shunt procedure, five surgeons provided an unaided free-recall description of the procedure using visual aids and surgical instruments (simulation), and one (chosen randomly) was interviewed using cognitive task analysis (CTA) methods. An 11th vascular surgeon approved the final CTA protocol. The CTA interview with only one expert surgeon resulted in significantly greater accuracy and completeness of the descriptions compared with the unaided free-recall interviews with multiple expert surgeons. Surgeons in the unaided group omitted nearly 70% of necessary decision steps. In the free-recall group, heavy use of simulation improved surgeons' completeness when describing the steps of the procedure. CTA significantly increases the completeness and accuracy of surgeons' instructional descriptions of surgical procedures. In addition, simulation during unaided free-recall interviews may improve the completeness of interview data. Copyright © 2012 Elsevier Inc

  15. Mechanism of failure of the Cabrol procedure: A computational fluid dynamic analysis.

    PubMed

    Poullis, M; Pullan, M

    2015-12-01

    Sudden failure of the Cabrol graft is common and frequently fatal. We utilised the technique of computational fluid dynamic (CFD) analysis to evaluate the mechanism of failure and potentially improve on the design of the Cabrol procedure. CFD analysis of the classic Cabrol procedure and a number of its variants was performed. Results from this analysis was utilised to generate further improved geometric options for the Cabrol procedure. These were also subjected to CFD analysis. All current Cabrol and variations of the Cabrol procedure are predicated by CFD analysis to be prone to graft thrombosis, secondary to stasis around the right coronary artery button. The right coronary artery flow characteristics were found to be the dominant reason for Cabrol graft failure. A simple modification of the Cabrol geometry is predicated to virtually eliminate any areas of blood stasis, and graft failure. Modification of the Cabrol graft geometry, due to CFD analysis may help reduce the incidence of graft thrombosis. A C shaped Cabrol graft with the right coronary button anastomosed to its side along its course from the aorta to the left coronary button is predicted to have the least thrombotic tendency. Clinical correlation is needed. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Characteristics of health interventions: a systematic analysis of the Austrian Procedure Catalogue.

    PubMed

    Neururer, Sabrina B; Pfeiffer, Karl-Peter

    2012-01-01

    The Austrian Procedure Catalogue contains 1,500 codes for health interventions used for performance-oriented hospital financing in Austria. It offers a multiaxial taxonomy. The aim of this study is to identify characteristics of medical procedures. Therefore a definition analysis followed by a typological analysis was conducted. Search strings were generated out of code descriptions regarding the heart, large vessels and cardiovascular system. Their definitions were looked up in the Pschyrembel Clinical Dictionary and documented. Out of these definitions, types which represent characteristics of health interventions were abstracted. The three axes of the Austrian Procedure Catalogue were approved as well as new, relevant information identified. The results are the foundation of a further enhancement of the Austrian Procedure Catalogue.

  17. First Outbreak with MRSA in a Danish Neonatal Intensive Care Unit: Risk Factors and Control Procedures

    PubMed Central

    Ramsing, Benedicte Grenness Utke; Arpi, Magnus; Andersen, Erik Arthur; Knabe, Niels; Mogensen, Dorthe; Buhl, Dorte; Westh, Henrik; Østergaard, Christian

    2013-01-01

    Introduction The purpose of the study was to describe demographic and clinical characteristics and outbreak handling of a large methicillin-resistant Staphylococcus aureus (MRSA) outbreak in a neonatal intensive care unit (NICU) in Denmark June 25th–August 8th 2008, and to identify risk factors for MRSA transmission. Methods Data were collected retrospectively from medical records and the Danish Neobase database. All MRSA isolates obtained from neonates, relatives and NICU health care workers (HCW) as well as environmental cultures were typed. Results During the 46 day outbreak period, 102 neonates were admitted to the two neonatal wards. Ninety-nine neonates were subsequently sampled, and 32 neonates (32%) from 25 families were colonized with MRSA (spa-type t127, SCCmec V, PVL negative). Thirteen family members from 11 of those families (44%) and two of 161 HCWs (1%) were colonized with the same MRSA. No one was infected. Five environmental cultures were MRSA positive. In a multiple logistic regression analysis, nasal Continuous Positive Airway Pressure (nCPAP) treatment (p = 0.006) and Caesarean section (p = 0.016) were independent risk factors for MRSA acquisition, whereas days of exposure to MRSA was a risk factors in the unadjusted analysis (p = 0.04). Conclusions MRSA transmission occurs with high frequency in the NICU during hospitalization with unidentified MRSA neonates. Caesarean section and nCPAP treatment were identified as risk factors for MRSA colonization. The MRSA outbreak was controlled through infection control procedures. PMID:23825581

  18. Confirmatory factor analysis of the Child Oral Health Impact Profile (Korean version).

    PubMed

    Cho, Young Il; Lee, Soonmook; Patton, Lauren L; Kim, Hae-Young

    2016-04-01

    Empirical support for the factor structure of the Child Oral Health Impact Profile (COHIP) has not been fully established. The purposes of this study were to evaluate the factor structure of the Korean version of the COHIP (COHIP-K) empirically using confirmatory factor analysis (CFA) based on the theoretical framework and then to assess whether any of the factors in the structure could be grouped into a simpler single second-order factor. Data were collected through self-reported COHIP-K responses from a representative community sample of 2,236 Korean children, 8-15 yr of age. Because a large inter-factor correlation of 0.92 was estimated in the original five-factor structure, the two strongly correlated factors were combined into one factor, resulting in a four-factor structure. The revised four-factor model showed a reasonable fit with appropriate inter-factor correlations. Additionally, the second-order model with four sub-factors was reasonable with sufficient fit and showed equal fit to the revised four-factor model. A cross-validation procedure confirmed the appropriateness of the findings. Our analysis empirically supported a four-factor structure of COHIP-K, a summarized second-order model, and the use of an integrated summary COHIP score. © 2016 Eur J Oral Sci.

  19. Hair decontamination procedure prior to multi-class pesticide analysis.

    PubMed

    Duca, Radu-Corneliu; Hardy, Emilie; Salquèbre, Guillaume; Appenzeller, Brice M R

    2014-06-01

    Although increasing interest is being observed in hair analysis for the biomonitoring of human exposure to pesticides, some limitations still have to be addressed for optimum use of this matrix in that specific context. One main possible issue concerns the need to differentiate chemicals biologically incorporated into hair from those externally deposited on hair surface from contaminated air or dust. The present study focuses on the development of a washing procedure for the decontamination of hair before analysis of pesticides from different chemical classes. For this purpose, three different procedures of artificial contamination (with silica, cellulose, and aqueous solution) were used to simulate pesticides deposition on hair surface. Several washing solvents (four organic: acetone, dichloromethane, methanol, acetonitrile; and four aqueous: water, phosphate buffer, shampoo, sodium dodecylsulfate) were evaluated for their capacity to remove artificially deposited pesticides from hair surface. The most effective washing solvents were sodium dodecylsulfate and methanol for aqueous and organic solvents, respectively. Moreover, after a first washing with sodium dodecylsulfate or methanol, the majority of externally deposited pesticides was removed and a steady-state was reached since significantly lower amounts were removed by additional second and third washings. Finally, the effectiveness of a decontamination procedure comprising washing with sodium dodecylsulfate and methanol was successively demonstrated. In parallel, it was determined that the final procedure did not affect the chemicals biologically incorporated, as hair strands naturally containing pesticides were used. Such a procedure appears to remove in one-shot the fraction of chemicals located on hair surface and does not require repeated washing steps. Copyright © 2014 John Wiley & Sons, Ltd.

  20. Hyperspectral data analysis procedures with reduced sensitivity to noise

    NASA Technical Reports Server (NTRS)

    Landgrebe, David A.

    1993-01-01

    Multispectral sensor systems have become steadily improved over the years in their ability to deliver increased spectral detail. With the advent of hyperspectral sensors, including imaging spectrometers, this technology is in the process of taking a large leap forward, thus providing the possibility of enabling delivery of much more detailed information. However, this direction of development has drawn even more attention to the matter of noise and other deleterious effects in the data, because reducing the fundamental limitations of spectral detail on information collection raises the limitations presented by noise to even greater importance. Much current effort in remote sensing research is thus being devoted to adjusting the data to mitigate the effects of noise and other deleterious effects. A parallel approach to the problem is to look for analysis approaches and procedures which have reduced sensitivity to such effects. We discuss some of the fundamental principles which define analysis algorithm characteristics providing such reduced sensitivity. One such analysis procedure including an example analysis of a data set is described, illustrating this effect.

  1. Risk factors for baclofen pump infection in children: a multivariate analysis.

    PubMed

    Spader, Heather S; Bollo, Robert J; Bowers, Christian A; Riva-Cambrin, Jay

    2016-06-01

    OBJECTIVE Intrathecal baclofen infusion systems to manage severe spasticity and dystonia are associated with higher infection rates in children than in adults. Factors unique to this population, such as poor nutrition and physical limitations for pump placement, have been hypothesized as the reasons for this disparity. The authors assessed potential risk factors for infection in a multivariate analysis. METHODS Patients who underwent implantation of a programmable pump and intrathecal catheter for baclofen infusion at a single center between January 1, 2000, and March 1, 2012, were identified in this retrospective cohort study. The primary end point was infection. Potential risk factors investigated included preoperative (i.e., demographics, body mass index [BMI], gastrostomy tube, tracheostomy, previous spinal fusion), intraoperative (i.e., surgeon, antibiotics, pump size, catheter location), and postoperative (i.e., wound dehiscence, CSF leak, and number of revisions) factors. Univariate analysis was performed, and a multivariate logistic regression model was created to identify independent risk factors for infection. RESULTS A total of 254 patients were evaluated. The overall infection rate was 9.8%. Univariate analysis identified young age, shorter height, lower weight, dehiscence, CSF leak, and number of revisions within 6 months of pump placement as significantly associated with infection. Multivariate analysis identified young age, dehiscence, and number of revisions as independent risk factors for infection. CONCLUSIONS Young age, wound dehiscence, and number of revisions were independent risk factors for infection in this pediatric cohort. A low BMI and the presence of either a gastrostomy or tracheostomy were not associated with infection and may not be contraindications for this procedure.

  2. Qualitative content analysis in nursing research: concepts, procedures and measures to achieve trustworthiness.

    PubMed

    Graneheim, U H; Lundman, B

    2004-02-01

    Qualitative content analysis as described in published literature shows conflicting opinions and unsolved issues regarding meaning and use of concepts, procedures and interpretation. This paper provides an overview of important concepts (manifest and latent content, unit of analysis, meaning unit, condensation, abstraction, content area, code, category and theme) related to qualitative content analysis; illustrates the use of concepts related to the research procedure; and proposes measures to achieve trustworthiness (credibility, dependability and transferability) throughout the steps of the research procedure. Interpretation in qualitative content analysis is discussed in light of Watzlawick et al.'s [Pragmatics of Human Communication. A Study of Interactional Patterns, Pathologies and Paradoxes. W.W. Norton & Company, New York, London] theory of communication.

  3. 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

  4. Microelectromechanical System (MEMS) Gyroscope Noise Analysis and Scale Factor Characterization over Temperature Variation

    DTIC Science & Technology

    2016-07-01

    bias and scale factor tests. By testing state-of-the-art gyroscopes, the effect of input rate stability and accuracy may be examined. Based on the...tumble test or bias analysis at a tilted position to remove the effect of Earth’s rotation in the scale factor test • A rate table with better rate...format guide and test procedure for coriolis vibratory gyros. Piscataway (NJ): IEEE; 2004 Dec. 3. Maio A, Smith G, Knight R, Nothwang W, Conroy J

  5. Pressure Ulcer Prevalence and Risk Factors among Prolonged Surgical Procedures in the OR

    PubMed Central

    Primiano, Mike; Friend, Michael; McClure, Connie; Nardi, Scott; Fix, Lisa; Schafer, Marianne; Savochka, Kathlyn; McNett, Molly

    2015-01-01

    Pressure ulcer formation related to positioning in the OR increases length of hospital stay and hospital costs, but there is little evidence documenting how positioning devices used in the OR influence pressure ulcer development when examined with traditional risk factors. The aim of this prospective cohort study was to identify prevalence of and risk factors associated with pressure ulcer development among patients undergoing surgical procedures lasting longer than three hours. Participants included all adult same-day admit patients scheduled for a three-hour surgical procedure during an eight-month period (N = 258). Data were gathered preoperatively, intraoperatively, and postoperatively on pressure ulcer risk factors. Bivariate analyses indicated that the type of positioning (ie, heels elevated) (χ2 = 7.897, P = .048), OR bed surface (ie, foam table pad) (χ2 15.848, P = .000), skin assessment in the postanesthesia care unit (χ2 = 41.652, P = .000), and male gender (χ2 = 6.984, P = .030) were associated with pressure ulcer development. Logistic regression analyses indicated that use of foam pad (B = 2.691, P = .024) and a lower day-one Braden score (B = .244, P = .003) were predictive of pressure ulcers. PMID:22118201

  6. Using Horn's Parallel Analysis Method in Exploratory Factor Analysis for Determining the Number of Factors

    ERIC Educational Resources Information Center

    Çokluk, Ömay; Koçak, Duygu

    2016-01-01

    In this study, the number of factors obtained from parallel analysis, a method used for determining the number of factors in exploratory factor analysis, was compared to that of the factors obtained from eigenvalue and scree plot--two traditional methods for determining the number of factors--in terms of consistency. Parallel analysis is based on…

  7. Risk factors for surgical site infection following nonshunt pediatric neurosurgery: a review of 9296 procedures from a national database and comparison with a single-center experience

    PubMed Central

    Sherrod, Brandon A.; Arynchyna, Anastasia A.; Johnston, James M.; Rozzelle, Curtis J.; Blount, Jeffrey P.; Oakes, W. Jerry; Rocque, Brandon G.

    2017-01-01

    Objective Surgical site infection (SSI) following CSF shunt operations has been well studied, yet risk factors for nonshunt pediatric neurosurgery are less well understood. The purpose of this study was to determine SSI rates and risk factors following nonshunt pediatric neurosurgery using a nationwide patient cohort and an institutional dataset specifically for better understanding SSI. Methods The authors reviewed the American College of Surgeons National Surgical Quality Improvement Program Pediatric (ACS NSQIP-P) database for the years 2012–2014, including all neurosurgical procedures performed on pediatric patients except CSF shunts and hematoma evacuations. SSI included deep (intracranial abscesses, meningitis, osteomyelitis, and ventriculitis) and superficial wound infections. The authors performed univariate analyses of SSI association with procedure, demographic, comorbidity, operative, and hospital variables, with subsequent multivariate logistic regression analysis to determine independent risk factors for SSI within 30 days of the index procedure. A similar analysis was performed using a detailed institutional infection database from Children’s Hospital of Alabama (COA). Results A total of 9296 nonshunt procedures were identified in NSQIP-P with an overall 30-day SSI rate of 2.7%. The 30-day SSI rate in the COA institutional database was similar (3.3% of 1103 procedures, p = 0.325). Postoperative time to SSI in NSQIP-P and COA was 14.6 ± 6.8 days and 14.8 ± 7.3 days, respectively (mean ± SD). Myelomeningocele (4.3% in NSQIP-P, 6.3% in COA), spine (3.5%, 4.9%), and epilepsy (3.4%, 3.1%) procedure categoriess had the highest SSI rates by procedure category in both NSQIP-P and COA. Independent SSI risk factors in NSQIP-P included postoperative pneumonia (OR 4.761, 95% CI 1.269–17.857, p = 0.021), immune disease/immunosuppressant use (OR 3.671, 95% CI 1.371–9.827, p = 0.010), cerebral palsy (OR 2.835, 95% CI 1.463–5.494, p = 0.002), emergency

  8. DSOD Procedures for Seismic Hazard Analysis

    NASA Astrophysics Data System (ADS)

    Howard, J. K.; Fraser, W. A.

    2005-12-01

    shaking levels are provided for sites far from active faulting. Our procedures and standards are presented at the DSOD website http://damsafety.water.ca.gov/. We review our methods and tools periodically under the guidance of our Consulting Board for Earthquake Analysis (and expect to make changes pending NGA completion), mindful that frequent procedural changes can interrupt design evaluations.

  9. Image-derived input function with factor analysis and a-priori information.

    PubMed

    Simončič, Urban; Zanotti-Fregonara, Paolo

    2015-02-01

    Quantitative PET studies often require the cumbersome and invasive procedure of arterial cannulation to measure the input function. This study sought to minimize the number of necessary blood samples by developing a factor-analysis-based image-derived input function (IDIF) methodology for dynamic PET brain studies. IDIF estimation was performed as follows: (a) carotid and background regions were segmented manually on an early PET time frame; (b) blood-weighted and tissue-weighted time-activity curves (TACs) were extracted with factor analysis; (c) factor analysis results were denoised and scaled using the voxels with the highest blood signal; (d) using population data and one blood sample at 40 min, whole-blood TAC was estimated from postprocessed factor analysis results; and (e) the parent concentration was finally estimated by correcting the whole-blood curve with measured radiometabolite concentrations. The methodology was tested using data from 10 healthy individuals imaged with [(11)C](R)-rolipram. The accuracy of IDIFs was assessed against full arterial sampling by comparing the area under the curve of the input functions and by calculating the total distribution volume (VT). The shape of the image-derived whole-blood TAC matched the reference arterial curves well, and the whole-blood area under the curves were accurately estimated (mean error 1.0±4.3%). The relative Logan-V(T) error was -4.1±6.4%. Compartmental modeling and spectral analysis gave less accurate V(T) results compared with Logan. A factor-analysis-based IDIF for [(11)C](R)-rolipram brain PET studies that relies on a single blood sample and population data can be used for accurate quantification of Logan-V(T) values.

  10. Determining the Number of Factors in P-Technique Factor Analysis

    ERIC Educational Resources Information Center

    Lo, Lawrence L.; Molenaar, Peter C. M.; Rovine, Michael

    2017-01-01

    Determining the number of factors is a critical first step in exploratory factor analysis. Although various criteria and methods for determining the number of factors have been evaluated in the usual between-subjects R-technique factor analysis, there is still question of how these methods perform in within-subjects P-technique factor analysis. A…

  11. Maximizing the Information and Validity of a Linear Composite in the Factor Analysis Model for Continuous Item Responses

    ERIC Educational Resources Information Center

    Ferrando, Pere J.

    2008-01-01

    This paper develops results and procedures for obtaining linear composites of factor scores that maximize: (a) test information, and (b) validity with respect to external variables in the multiple factor analysis (FA) model. I treat FA as a multidimensional item response theory model, and use Ackerman's multidimensional information approach based…

  12. Analysis of simulated angiographic procedures. Part 2: extracting efficiency data from audio and video recordings.

    PubMed

    Duncan, James R; Kline, Benjamin; Glaiberman, Craig B

    2007-04-01

    To create and test methods of extracting efficiency data from recordings of simulated renal stent procedures. Task analysis was performed and used to design a standardized testing protocol. Five experienced angiographers then performed 16 renal stent simulations using the Simbionix AngioMentor angiographic simulator. Audio and video recordings of these simulations were captured from multiple vantage points. The recordings were synchronized and compiled. A series of efficiency metrics (procedure time, contrast volume, and tool use) were then extracted from the recordings. The intraobserver and interobserver variability of these individual metrics was also assessed. The metrics were converted to costs and aggregated to determine the fixed and variable costs of a procedure segment or the entire procedure. Task analysis and pilot testing led to a standardized testing protocol suitable for performance assessment. Task analysis also identified seven checkpoints that divided the renal stent simulations into six segments. Efficiency metrics for these different segments were extracted from the recordings and showed excellent intra- and interobserver correlations. Analysis of the individual and aggregated efficiency metrics demonstrated large differences between segments as well as between different angiographers. These differences persisted when efficiency was expressed as either total or variable costs. Task analysis facilitated both protocol development and data analysis. Efficiency metrics were readily extracted from recordings of simulated procedures. Aggregating the metrics and dividing the procedure into segments revealed potential insights that could be easily overlooked because the simulator currently does not attempt to aggregate the metrics and only provides data derived from the entire procedure. The data indicate that analysis of simulated angiographic procedures will be a powerful method of assessing performance in interventional radiology.

  13. Replica Analysis for Portfolio Optimization with Single-Factor Model

    NASA Astrophysics Data System (ADS)

    Shinzato, Takashi

    2017-06-01

    In this paper, we use replica analysis to investigate the influence of correlation among the return rates of assets on the solution of the portfolio optimization problem. We consider the behavior of an optimal solution for the case where the return rate is described with a single-factor model and compare the findings obtained from our proposed methods with correlated return rates with those obtained with independent return rates. We then analytically assess the increase in the investment risk when correlation is included. Furthermore, we also compare our approach with analytical procedures for minimizing the investment risk from operations research.

  14. Main clinical, therapeutic and technical factors related to patient's maximum skin dose in interventional cardiology procedures

    PubMed Central

    Journy, N; Sinno-Tellier, S; Maccia, C; Le Tertre, A; Pirard, P; Pagès, P; Eilstein, D; Donadieu, J; Bar, O

    2012-01-01

    Objective The study aimed to characterise the factors related to the X-ray dose delivered to the patient's skin during interventional cardiology procedures. Methods We studied 177 coronary angiographies (CAs) and/or percutaneous transluminal coronary angioplasties (PTCAs) carried out in a French clinic on the same radiography table. The clinical and therapeutic characteristics, and the technical parameters of the procedures, were collected. The dose area product (DAP) and the maximum skin dose (MSD) were measured by an ionisation chamber (Diamentor; Philips, Amsterdam, The Netherlands) and radiosensitive film (Gafchromic; International Specialty Products Advanced Materials Group, Wayne, NJ). Multivariate analyses were used to assess the effects of the factors of interest on dose. Results The mean MSD and DAP were respectively 389 mGy and 65 Gy cm−2 for CAs, and 916 mGy and 69 Gy cm−2 for PTCAs. For 8% of the procedures, the MSD exceeded 2 Gy. Although a linear relationship between the MSD and the DAP was observed for CAs (r=0.93), a simple extrapolation of such a model to PTCAs would lead to an inadequate assessment of the risk, especially for the highest dose values. For PTCAs, the body mass index, the therapeutic complexity, the fluoroscopy time and the number of cine frames were independent explanatory factors of the MSD, whoever the practitioner was. Moreover, the effect of technical factors such as collimation, cinematography settings and X-ray tube orientations on the DAP was shown. Conclusion Optimising the technical options for interventional procedures and training staff on radiation protection might notably reduce the dose and ultimately avoid patient skin lesions. PMID:22457404

  15. On the stability analysis of approximate factorization methods for 3D Euler and Navier-Stokes equations

    NASA Technical Reports Server (NTRS)

    Demuren, A. O.; Ibraheem, S. O.

    1993-01-01

    The convergence characteristics of various approximate factorizations for the 3D Euler and Navier-Stokes equations are examined using the von-Neumann stability analysis method. Three upwind-difference based factorizations and several central-difference based factorizations are considered for the Euler equations. In the upwind factorizations both the flux-vector splitting methods of Steger and Warming and van Leer are considered. Analysis of the Navier-Stokes equations is performed only on the Beam and Warming central-difference scheme. The range of CFL numbers over which each factorization is stable is presented for one-, two-, and three-dimensional flow. Also presented for each factorization is the CFL number at which the maximum eigenvalue is minimized, for all Fourier components, as well as for the high frequency range only. The latter is useful for predicting the effectiveness of multigrid procedures with these schemes as smoothers. Further, local mode analysis is performed to test the suitability of using a uniform flow field in the stability analysis. Some inconsistencies in the results from previous analyses are resolved.

  16. Optimizing modality selection for image-guided procedures: an analysis of the challenges to ultrasound guidance.

    PubMed

    Beland, Michael D; Sternick, Laura A; Baird, Grayson L; Dupuy, Damian E; Cronan, John J; Mayo-Smith, William W

    2016-04-01

    Selection of the most appropriate modality for image guidance is essential for procedural success. We identified specific factors contributing to failure of ultrasound-guided procedures that were subsequently performed using CT guidance. This single-center, retrospective study included 164 patients who underwent a CT-guided biopsy, aspiration/drainage, or ablation after initially having the same procedure attempted unsuccessfully with ultrasound guidance. Review of the procedure images, reports, biopsy results, and clinical follow-up was performed and the reasons for inability to perform the procedure with ultrasound guidance were recorded. Patient cross-sectional area and depth to target were calculated. Differences in area and depth were compared using general linear modeling. Depth as a predictor of an unfavorable body habitus designation was modeled using logistic regression. US guidance was successful in the vast majority of cases (97%). Of the 164 procedures, there were 92 (56%) biopsies, 63 (38%) aspirations/drainages, and 9 (5%) ablations. The most common reason for procedure failure was poor acoustic window (83/164, 51%). Other reasons included target lesion being poorly discerned from adjacent tissue (61/164, 37%), adjacent bowel gas (34/164, 21%), body habitus (27/164, 16%), and gas-containing collection (22/164, 13%). Within the biopsy subgroup, patients for whom body habitus was a limiting factor were found to have on average a larger cross-sectional area and lesion depth relative to patients whose body habitus was not a complicating factor (p < 0.0001 and p = 0.0009). Poor acoustic window was the most common reason for procedural failure with ultrasound guidance. In addition, as lesion depth increased, the odds that body habitus would limit the procedure also increased. If preliminary imaging suggests a limited sonographic window, particularly for deeper lesions, proceeding directly to CT guidance should be considered.

  17. Old and New Ideas for Data Screening and Assumption Testing for Exploratory and Confirmatory Factor Analysis

    PubMed Central

    Flora, David B.; LaBrish, Cathy; Chalmers, R. Philip

    2011-01-01

    We provide a basic review of the data screening and assumption testing issues relevant to exploratory and confirmatory factor analysis along with practical advice for conducting analyses that are sensitive to these concerns. Historically, factor analysis was developed for explaining the relationships among many continuous test scores, which led to the expression of the common factor model as a multivariate linear regression model with observed, continuous variables serving as dependent variables, and unobserved factors as the independent, explanatory variables. Thus, we begin our paper with a review of the assumptions for the common factor model and data screening issues as they pertain to the factor analysis of continuous observed variables. In particular, we describe how principles from regression diagnostics also apply to factor analysis. Next, because modern applications of factor analysis frequently involve the analysis of the individual items from a single test or questionnaire, an important focus of this paper is the factor analysis of items. Although the traditional linear factor model is well-suited to the analysis of continuously distributed variables, commonly used item types, including Likert-type items, almost always produce dichotomous or ordered categorical variables. We describe how relationships among such items are often not well described by product-moment correlations, which has clear ramifications for the traditional linear factor analysis. An alternative, non-linear factor analysis using polychoric correlations has become more readily available to applied researchers and thus more popular. Consequently, we also review the assumptions and data-screening issues involved in this method. Throughout the paper, we demonstrate these procedures using an historic data set of nine cognitive ability variables. PMID:22403561

  18. Validation of the Adolescent Concerns Measure (ACM): evidence from exploratory and confirmatory factor analysis.

    PubMed

    Ang, Rebecca P; Chong, Wan Har; Huan, Vivien S; Yeo, Lay See

    2007-01-01

    This article reports the development and initial validation of scores obtained from the Adolescent Concerns Measure (ACM), a scale which assesses concerns of Asian adolescent students. In Study 1, findings from exploratory factor analysis using 619 adolescents suggested a 24-item scale with four correlated factors--Family Concerns (9 items), Peer Concerns (5 items), Personal Concerns (6 items), and School Concerns (4 items). Initial estimates of convergent validity for ACM scores were also reported. The four-factor structure of ACM scores derived from Study 1 was confirmed via confirmatory factor analysis in Study 2 using a two-fold cross-validation procedure with a separate sample of 811 adolescents. Support was found for both the multidimensional and hierarchical models of adolescent concerns using the ACM. Internal consistency and test-retest reliability estimates were adequate for research purposes. ACM scores show promise as a reliable and potentially valid measure of Asian adolescents' concerns.

  19. Pricing of common cosmetic surgery procedures: local economic factors trump supply and demand.

    PubMed

    Richardson, Clare; Mattison, Gennaya; Workman, Adrienne; Gupta, Subhas

    2015-02-01

    The pricing of cosmetic surgery procedures has long been thought to coincide with laws of basic economics, including the model of supply and demand. However, the highly variable prices of these procedures indicate that additional economic contributors are probable. The authors sought to reassess the fit of cosmetic surgery costs to the model of supply and demand and to determine the driving forces behind the pricing of cosmetic surgery procedures. Ten plastic surgery practices were randomly selected from each of 15 US cities of various population sizes. Average prices of breast augmentation, mastopexy, abdominoplasty, blepharoplasty, and rhytidectomy in each city were compared with economic and demographic statistics. The average price of cosmetic surgery procedures correlated substantially with population size (r = 0.767), cost-of-living index (r = 0.784), cost to own real estate (r = 0.714), and cost to rent real estate (r = 0.695) across the 15 US cities. Cosmetic surgery pricing also was found to correlate (albeit weakly) with household income (r = 0.436) and per capita income (r = 0.576). Virtually no correlations existed between pricing and the density of plastic surgeons (r = 0.185) or the average age of residents (r = 0.076). Results of this study demonstrate a correlation between costs of cosmetic surgery procedures and local economic factors. Cosmetic surgery pricing cannot be completely explained by the supply-and-demand model because no association was found between procedure cost and the density of plastic surgeons. © 2015 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

  20. Pertinent anatomy and analysis for midface volumizing procedures.

    PubMed

    Surek, Christopher C; Beut, Javier; Stephens, Robert; Jelks, Glenn; Lamb, Jerome

    2015-05-01

    The study was conducted to construct an anatomically inspired midfacial analysis facilitating safe, accurate, and dynamic nonsurgical rejuvenation. Emphasis is placed on determining injection target areas and adverse event zones. Twelve hemifacial fresh cadavers were dissected in a layered fashion. Dimensional measurements between the midfacial fat compartments, prezygomatic space, mimetic muscles, and neurovascular bundles were used to develop a topographic analysis for clinical injections. A longitudinal line from the base of the alar crease to the medial edge of the levator anguli oris muscle (1.9 cm), lateral edge of the levator anguli oris muscle (2.6 cm), and zygomaticus major muscle (4.6 cm) partitions the cheek into two aesthetic regions. A six-step facial analysis outlines three target zones and two adverse event zones and triangulates the point of maximum cheek projection. The lower adverse event zone yields an anatomical explanation to inadvertent jowling during anterior cheek injection. The upper adverse event zone localizes the palpebral branch of the infraorbital artery. The medial malar target area isolates quadrants for anterior cheek projection and tear trough effacement. The middle malar target area addresses lid-cheek blending and superficial compartment turgor. The lateral malar target area highlights lateral cheek projection and locates the prezygomatic space. This stepwise analysis illustrates target areas and adverse event zones to achieve midfacial support, contour, and profile in the repose position and simultaneous molding of a natural shape during animation. This reproducible method can be used both procedurally and in record-keeping for midface volumizing procedures.

  1. Epidemiologic Analysis of Elective Operative Procedures in Infants Less Than 6 Months of Age in the United States.

    PubMed

    Einhorn, Lisa M; Young, Brian J; Routh, Jonathan C; Allori, Alexander C; Tracy, Elisabeth T; Greene, Nathaniel H

    2017-11-01

    This study uses publicly available data to analyze the total number of elective, potentially deferrable operative procedures involving infants <6 months of age in the United States. We investigated the factors associated with the performance of these procedures in this population. The State Ambulatory Surgery Database was used to identify patients in California, North Carolina, New York, and Utah during the years of 2007-2010 who were younger than 6 months of age at the time that they underwent outpatient (ambulatory) surgery. Operations that could reasonably be postponed until 6 months of age were classified as potentially deferrable procedures. Hernia repairs were analyzed separately from other deferrable procedures. Primary outcomes included the total number of elective procedures and the number and rates of potentially deferrable procedures per state per year in this population. Over the study period, a total of 27,540 procedures were identified as meeting inclusion criteria; of those, 7832 (28%) were classified as potentially deferrable, 4315 of which were hernia repairs. The average rates of potentially deferrable nonhernia procedures in California, North Carolina, New York, and Utah were 8.3, 43.8, 30.0, and 11.7 per 10,000 person-years, respectively. In multivariable analysis, private insurance (odds ratio [OR] = 1.36), self-pay status (OR = 1.50), and treatment in a different state (OR = 0.48-3.16) were independent predictors of a potentially deferrable procedure being performed on an infant younger than 6 months. Potentially deferrable procedures are still performed in infants <6 months of age. There appears to be significant variation in timing of these procedures among states. Insurance status and geography may be independent predictors of a procedure being potentially deferrable.

  2. Stent-Assisted Coil Embolization of Vertebrobasilar Dissecting Aneurysms: Procedural Outcomes and Factors for Recanalization.

    PubMed

    Jeon, Jin Pyeong; Cho, Young Dae; Rhim, Jong Kook; Park, Jeong Jin; Cho, Won-Sang; Kang, Hyun-Seung; Kim, Jeong Eun; Hwang, Gyojun; Kwon, O-Ki; Han, Moon Hee

    2016-01-01

    Outcomes of stent-assisted coil embolization (SACE) have not been well established in the setting of vertebrobasilar dissecting aneurysms (VBDAs) due to the low percentage of cases that need treatment and the array of available therapeutic options. Herein, we presented clinical and radiographic results of SACE in patients with VBDAs. A total of 47 patients (M:F, 30:17; mean age ± SD, 53.7 ± 12.6 years), with a VBDA who underwent SACE between 2008 and 2014 at two institutions were evaluated retrospectively. Medical records and radiologic data were analyzed to assess the outcome of SACE procedures. Cox proportional hazards regression analysis was conducted to determine the factors that were associated with aneurysmal recanalization after SACE. Stent-assisted coil embolization technically succeeded in all patients. Three cerebellar infarctions occurred on postembolization day 1, week 2, and month 2, but no other procedure-related complications developed. Immediately following SACE, 25 aneurysms (53.2%) showed no contrast filling into the aneurysmal sac. During a mean follow-up of 20.2 months, 37 lesions (78.7%) appeared completely occluded, whereas 10 lesions showed recanalization, 5 of which required additional embolization. Overall recanalization rate was 12.64% per lesion-year, and mean postoperative time to recanalization was 18 months (range, 3-36 months). In multivariable analysis, major branch involvement (hazard ratio [HR]: 7.28; p = 0.013) and the presence of residual sac filling (HR: 8.49, p = 0.044) were identified as statistically significant independent predictors of recanalization. No bleeding was encountered in follow-up monitoring. Stent-assisted coil embolization appears feasible and safe for treatment of VBDAs. Long-term results were acceptable in a majority of patients studied, despite a relatively high rate of incomplete occlusion immediately after SACE. Major branch involvement and coiled aneurysms with residual sac filling may predispose to

  3. Initial Investigation of Factors Influencing Radiation Dose to Patients Undergoing Barium-Based Fluoroscopy Procedures in Tanzania.

    PubMed

    Ngaile, J E; Msaki, P K; Kazema, R R; Schreiner, L J

    2017-04-25

    The aim of this study was to investigate the nature and causes of radiation dose imparted to patients undergoing barium-based X-ray fluoroscopy procedures in Tanzania and to compare these doses to those reported in the literature from other regions worldwide. The air kerma area product (KAP) to patient undergoing barium investigations of gastrointestinal tract system was obtained from four consultant hospitals. The KAP was determined using a flat transparent transmission ionization chamber. Mean values of KAP for barium swallow (BS), barium meal (BM) and barium enema (BE) were 2.79, 2.62 and 15.04 Gy cm2, respectively. The mean values of KAP per hospital for the BS, BM and BE procedures varied by factors of up to 7.3, 1.6 and 2.0, respectively. The overall difference between individual patient doses across the four consultant hospitals investigated differed by factors of up to 53, 29.5 and 12 for the BS, BM and BE procedures, respectively. The majority of the mean values of KAP was lower than the reported values for Ghana, Greece, Spain and the UK, while slightly higher than those reported for India. The observed wide variation of KAP values for the same fluoroscopy procedure within and among the hospitals was largely attributed to the dynamic nature of the procedures, the patient characteristics, the skills and experience of personnel, and the different examination protocols employed among hospitals. The observed great variations of procedural protocols and patient doses within and across the hospitals call for the need to standardize examination protocols and optimize barium-based fluoroscopy procedures. © The Author 2016. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Risk analysis procedure for post-wildfire natural hazards in British Columbia

    NASA Astrophysics Data System (ADS)

    Jordan, Peter

    2010-05-01

    Following a severe wildfire season in 2003, and several subsequent damaging debris flow and flood events, the British Columbia Forest Service developed a procedure for analysing risks to public safety and infrastructure from such events. At the same time, the Forest Service undertook a research program to determine the extent of post-wildfire hazards, and examine the hydrologic and geomorphic processes contributing to the hazards. The risk analysis procedure follows the Canadian Standards Association decision-making framework for risk management (which in turn is based on international standards). This has several steps: identification of risk, risk analysis and estimation, evaluation of risk tolerability, developing control or mitigation strategies, and acting on these strategies. The Forest Service procedure deals only with the first two steps. The results are passed on to authorities such as the Provincial Emergency Program and local government, who are responsible for evaluating risks, warning residents, and applying mitigation strategies if appropriate. The objective of the procedure is to identify and analyse risks to public safety and infrastructure. The procedure is loosely based on the BAER (burned area emergency response) program in the USA, with some important differences. Our procedure focuses on identifying risks and warning affected parties, not on mitigation activities such as broadcast erosion control measures. Partly this is due to limited staff and financial resources. Also, our procedure is not multi-agency, but is limited to wildfires on provincial forest land; in British Columbia about 95% of forest land is in the publicly-owned provincial forest. Each fire season, wildfires are screened by size and proximity to values at risk such as populated areas. For selected fires, when the fire is largely contained, the procedure begins with an aerial reconnaissance of the fire, and photography with a hand-held camera, which can be used to make a

  5. Risk Factors for 30-Day Hospital Re-Admission with an Infectious Complication after Lower-Extremity Vascular Procedures.

    PubMed

    Melvin, Joseph C; Smith, Jamie B; Kruse, Robin L; Vogel, Todd R

    2017-04-01

    Lowering the 30-d re-admission rate after vascular surgery offers the potential to improve healthcare quality. This study evaluated re-admission associated with infections after open and endovascular lower extremity (LE) procedures for peripheral artery disease (PAD). Patients admitted for elective LE procedures for PAD were selected from the Cerner Health Facts ® database. Chi-square analysis evaluated the characteristics of the index admission associated with infection at 30-d re-admission. Multivariable logistic models were created to examine the association of patient and procedural characteristics with infections at re-admission. The microbiology data available at the time of re-admission were evaluated also. A total of 7,089 patients underwent elective LE procedures, of whom 770 (10.9%) were re-admitted within 30 d. A total of 289 (37.5%) had a diagnosis of infection during the re-admission. These infections included surgical site (14.8%), cellulitis (13.6%), sepsis (8.8%), urinary tract (4.9%), and pneumonia (4.9%). Index stay factors associated with infection at re-admission were fluid and electrolyte disorders, kidney disease, diabetes, previous infection, and chronic anemia. Laboratory results associated with an infection during re-admission were post-operative hemoglobin <8 g/dL, blood urea nitrogen >20 mg/dL, platelet counts >400 × 10 3 /mcL, glucose >180 mg/dL, and white blood cell count >11.0 × 10 3 /mcL. Adjusted models demonstrated longer stay, chronic anemia, previous infection, treatment at a teaching hospital, and hemoglobin <8 g/dL to be risk factors for re-admission with infection. Infective organisms isolated during the re-admission stay included Staphylococcus, Enterococcus, Escherichia, Pseudomonas, Proteus, and Klebsiella. Infectious complications were associated with more than one-third of all re-admissions after LE procedures. Predictors of re-admission within 30 d with an infectious complication were longer stay

  6. Documentation for a Structural Optimization Procedure Developed Using the Engineering Analysis Language (EAL)

    NASA Technical Reports Server (NTRS)

    Martin, Carl J., Jr.

    1996-01-01

    This report describes a structural optimization procedure developed for use with the Engineering Analysis Language (EAL) finite element analysis system. The procedure is written primarily in the EAL command language. Three external processors which are written in FORTRAN generate equivalent stiffnesses and evaluate stress and local buckling constraints for the sections. Several built-up structural sections were coded into the design procedures. These structural sections were selected for use in aircraft design, but are suitable for other applications. Sensitivity calculations use the semi-analytic method, and an extensive effort has been made to increase the execution speed and reduce the storage requirements. There is also an approximate sensitivity update method included which can significantly reduce computational time. The optimization is performed by an implementation of the MINOS V5.4 linear programming routine in a sequential liner programming procedure.

  7. Standardized Procedure Content And Data Structure Based On Human Factors Requirements For Computer-Based Procedures

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

    Bly, Aaron; Oxstrand, Johanna; Le Blanc, Katya L

    2015-02-01

    Most activities that involve human interaction with systems in a nuclear power plant are guided by procedures. Traditionally, the use of procedures has been a paper-based process that supports safe operation of the nuclear power industry. However, the nuclear industry is constantly trying to find ways to decrease the human error rate, especially the human errors associated with procedure use. Advances in digital technology make computer-based procedures (CBPs) a valid option that provides further enhancement of safety by improving human performance related to procedure use. The transition from paper-based procedures (PBPs) to CBPs creates a need for a computer-based proceduremore » system (CBPS). A CBPS needs to have the ability to perform logical operations in order to adjust to the inputs received from either users or real time data from plant status databases. Without the ability for logical operations the procedure is just an electronic copy of the paper-based procedure. In order to provide the CBPS with the information it needs to display the procedure steps to the user, special care is needed in the format used to deliver all data and instructions to create the steps. The procedure should be broken down into basic elements and formatted in a standard method for the CBPS. One way to build the underlying data architecture is to use an Extensible Markup Language (XML) schema, which utilizes basic elements to build each step in the smart procedure. The attributes of each step will determine the type of functionality that the system will generate for that step. The CBPS will provide the context for the step to deliver referential information, request a decision, or accept input from the user. The XML schema needs to provide all data necessary for the system to accurately perform each step without the need for the procedure writer to reprogram the CBPS. The research team at the Idaho National Laboratory has developed a prototype CBPS for field workers as well as

  8. Economic analysis of the future growth of cosmetic surgery procedures.

    PubMed

    Liu, Tom S; Miller, Timothy A

    2008-06-01

    The economic growth of cosmetic surgical and nonsurgical procedures has been tremendous. Between 1992 and 2005, annual U.S. cosmetic surgery volume increased by 725 percent, with over $10 billion spent in 2005. It is unknown whether this growth will continue for the next decade and, if so, what impact it will it have on the plastic surgeon workforce. The authors analyzed annual U.S. cosmetic surgery procedure volume reported by the American Society of Plastic Surgeons (ASPS) National Clearinghouse of Plastic Surgery Statistics between 1992 and 2005. Reconstructive plastic surgery volume was not included in the analysis. The authors analyzed the ability of economic and noneconomic variables to predict annual cosmetic surgery volume. The authors also used growth rate analyses to construct models with which to predict the future growth of cosmetic surgery. None of the economic and noneconomic variables were a significant predictor of annual cosmetic surgery volume. Instead, based on current compound annual growth rates, the authors predict that total cosmetic surgery volume (surgical and nonsurgical) will exceed 55 million annual procedures by 2015. ASPS members are projected to perform 299 surgical and 2165 nonsurgical annual procedures. Non-ASPS members are projected to perform 39 surgical and 1448 nonsurgical annual procedures. If current growth rates continue into the next decade, the future demand in cosmetic surgery will be driven largely by nonsurgical procedures. The growth of surgical procedures will be met by ASPS members. However, meeting the projected growth in nonsurgical procedures could be a potential challenge and a potential area for increased competition.

  9. Procedural Fidelity: An Analysis of Measurement and Reporting Practices

    ERIC Educational Resources Information Center

    Ledford, Jennifer R.; Wolery, Mark

    2013-01-01

    A systematic analysis was conducted of measurement and reporting practices related to procedural fidelity in single-case research for the past 30 years. Previous reviews of fidelity primarily reported whether fidelity data were collected by authors; these reviews reported that collection was variable, but low across journals and over time. Results…

  10. Latent Class Detection and Class Assignment: A Comparison of the MAXEIG Taxometric Procedure and Factor Mixture Modeling Approaches

    ERIC Educational Resources Information Center

    Lubke, Gitta; Tueller, Stephen

    2010-01-01

    Taxometric procedures such as MAXEIG and factor mixture modeling (FMM) are used in latent class clustering, but they have very different sets of strengths and weaknesses. Taxometric procedures, popular in psychiatric and psychopathology applications, do not rely on distributional assumptions. Their sole purpose is to detect the presence of latent…

  11. Effect of Purification Procedures on DIF Analysis in IRTPRO

    ERIC Educational Resources Information Center

    Fikis, David R. J.; Oshima, T. C.

    2017-01-01

    Purification of the test has been a well-accepted procedure in enhancing the performance of tests for differential item functioning (DIF). As defined by Lord, purification requires reestimation of ability parameters after removing DIF items before conducting the final DIF analysis. IRTPRO 3 is a recently updated program for analyses in item…

  12. Responding to Self-Harm: A Documentary Analysis of Agency Policy and Procedure

    ERIC Educational Resources Information Center

    Paul, Sally; Hill, Malcolm

    2013-01-01

    This paper reports on the findings of a documentary analysis of policies and procedures relating to self-harm from a range of organisations working with young people in the UK. It identifies the extent to which policies and/or procedures relating to self-harm are available for service providers and offers a wider understanding of the concepts of…

  13. Factors affecting construction performance: exploratory factor analysis

    NASA Astrophysics Data System (ADS)

    Soewin, E.; Chinda, T.

    2018-04-01

    The present work attempts to develop a multidimensional performance evaluation framework for a construction company by considering all relevant measures of performance. Based on the previous studies, this study hypothesizes nine key factors, with a total of 57 associated items. The hypothesized factors, with their associated items, are then used to develop questionnaire survey to gather data. The exploratory factor analysis (EFA) was applied to the collected data which gave rise 10 factors with 57 items affecting construction performance. The findings further reveal that the items constituting ten key performance factors (KPIs) namely; 1) Time, 2) Cost, 3) Quality, 4) Safety & Health, 5) Internal Stakeholder, 6) External Stakeholder, 7) Client Satisfaction, 8) Financial Performance, 9) Environment, and 10) Information, Technology & Innovation. The analysis helps to develop multi-dimensional performance evaluation framework for an effective measurement of the construction performance. The 10 key performance factors can be broadly categorized into economic aspect, social aspect, environmental aspect, and technology aspects. It is important to understand a multi-dimension performance evaluation framework by including all key factors affecting the construction performance of a company, so that the management level can effectively plan to implement an effective performance development plan to match with the mission and vision of the company.

  14. 75 FR 70664 - Guidelines Establishing Test Procedures for the Analysis of Pollutants Under the Clean Water Act...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-18

    ... Act; Analysis and Sampling Procedures; Extension of Comment Period AGENCY: Environmental Protection..., 2010, EPA proposed changes to analysis and sampling test procedures in wastewater regulations. These...

  15. A scaling procedure for the response of an isolated system with high modal overlap factor

    NASA Astrophysics Data System (ADS)

    De Rosa, S.; Franco, F.

    2008-10-01

    The paper deals with a numerical approach that reduces some physical sizes of the solution domain to compute the dynamic response of an isolated system: it has been named Asymptotical Scaled Modal Analysis (ASMA). The proposed numerical procedure alters the input data needed to obtain the classic modal responses to increase the frequency band of validity of the discrete or continuous coordinates model through the definition of a proper scaling coefficient. It is demonstrated that the computational cost remains acceptable while the frequency range of analysis increases. Moreover, with reference to the flexural vibrations of a rectangular plate, the paper discusses the ASMA vs. the statistical energy analysis and the energy distribution approach. Some insights are also given about the limits of the scaling coefficient. Finally it is shown that the linear dynamic response, predicted with the scaling procedure, has the same quality and characteristics of the statistical energy analysis, but it can be useful when the system cannot be solved appropriately by the standard Statistical Energy Analysis (SEA).

  16. ICAP - An Interactive Cluster Analysis Procedure for analyzing remotely sensed data

    NASA Technical Reports Server (NTRS)

    Wharton, S. W.; Turner, B. J.

    1981-01-01

    An Interactive Cluster Analysis Procedure (ICAP) was developed to derive classifier training statistics from remotely sensed data. ICAP differs from conventional clustering algorithms by allowing the analyst to optimize the cluster configuration by inspection, rather than by manipulating process parameters. Control of the clustering process alternates between the algorithm, which creates new centroids and forms clusters, and the analyst, who can evaluate and elect to modify the cluster structure. Clusters can be deleted, or lumped together pairwise, or new centroids can be added. A summary of the cluster statistics can be requested to facilitate cluster manipulation. The principal advantage of this approach is that it allows prior information (when available) to be used directly in the analysis, since the analyst interacts with ICAP in a straightforward manner, using basic terms with which he is more likely to be familiar. Results from testing ICAP showed that an informed use of ICAP can improve classification, as compared to an existing cluster analysis procedure.

  17. A Bayesian procedure for evaluating the frequency of calibration factor updates in highway safety manual (HSM) applications.

    PubMed

    Saha, Dibakar; Alluri, Priyanka; Gan, Albert

    2017-01-01

    The Highway Safety Manual (HSM) presents statistical models to quantitatively estimate an agency's safety performance. The models were developed using data from only a few U.S. states. To account for the effects of the local attributes and temporal factors on crash occurrence, agencies are required to calibrate the HSM-default models for crash predictions. The manual suggests updating calibration factors every two to three years, or preferably on an annual basis. Given that the calibration process involves substantial time, effort, and resources, a comprehensive analysis of the required calibration factor update frequency is valuable to the agencies. Accordingly, the objective of this study is to evaluate the HSM's recommendation and determine the required frequency of calibration factor updates. A robust Bayesian estimation procedure is used to assess the variation between calibration factors computed annually, biennially, and triennially using data collected from over 2400 miles of segments and over 700 intersections on urban and suburban facilities in Florida. Bayesian model yields a posterior distribution of the model parameters that give credible information to infer whether the difference between calibration factors computed at specified intervals is credibly different from the null value which represents unaltered calibration factors between the comparison years or in other words, zero difference. The concept of the null value is extended to include the range of values that are practically equivalent to zero. Bayesian inference shows that calibration factors based on total crash frequency are required to be updated every two years in cases where the variations between calibration factors are not greater than 0.01. When the variations are between 0.01 and 0.05, calibration factors based on total crash frequency could be updated every three years. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Thromboembolic Risks of the Procedural Process in Second-Generation Cryoballoon Ablation Procedures: Analysis From Real-Time Transcranial Doppler Monitoring.

    PubMed

    Miyazaki, Shinsuke; Watanabe, Tomonori; Kajiyama, Takatsugu; Iwasawa, Jin; Ichijo, Sadamitsu; Nakamura, Hiroaki; Taniguchi, Hiroshi; Hirao, Kenzo; Iesaka, Yoshito

    2017-12-01

    Atrial fibrillation ablation is associated with substantial risks of silent cerebral events (SCEs) or silent cerebral lesions. We investigated which procedural processes during cryoballoon procedures carried a risk. Forty paroxysmal atrial fibrillation patients underwent pulmonary vein isolation using second-generation cryoballoons with single 28-mm balloon 3-minute freeze techniques. Microembolic signals (MESs) were monitored by transcranial Doppler throughout all procedures. Brain magnetic resonance imaging was obtained pre- and post-procedure in 34 patients (85.0%). Of 158 pulmonary veins, 152 (96.2%) were isolated using cryoablation, and 6 required touch-up radiofrequency ablation. A mean of 5.0±1.2 cryoballoon applications was applied, and the left atrial dwell time was 76.7±22.4 minutes. The total MES counts/procedures were 522 (426-626). Left atrial access and Flexcath sheath insertion generated 25 (11-44) and 34 (24-53) MESs. Using radiofrequency ablation for transseptal access increased the MES count during transseptal punctures. During cryoapplications, MES counts were greatest during first applications (117 [81-157]), especially after balloon stretch/deflations (43 [21-81]). Pre- and post-pulmonary vein potential mapping with Lasso catheters generated 57 (21-88) and 61 (36-88) MESs. Reinsertion of once withdrawn cryoballoons and subsequent applications produced 205 (156-310) MESs. Touch-up ablation generated 32 (19-62) MESs, whereas electric cardioversion generated no MESs. SCEs and silent cerebral lesions were detected in 11 (32.3%) and 4 (11.7%) patients, respectively. The patients with SCEs were older than those without; however, there were no significant factors associated with SCEs. A significant number of MESs and SCE/silent cerebral lesion occurrences were observed during second-generation cryoballoon ablation procedures. MESs were recorded during a variety of steps throughout the procedure; however, the majority occurred during phases with a

  19. Gastroesophageal reflux disease after peroral endoscopic myotomy: Analysis of clinical, procedural and functional factors, associated with gastroesophageal reflux disease and esophagitis.

    PubMed

    Familiari, Pietro; Greco, Santi; Gigante, Giovanni; Calì, Anna; Boškoski, Ivo; Onder, Graziano; Perri, Vincenzo; Costamagna, Guido

    2016-01-01

    Peroral endoscopic myotomy (POEM) does not include any antireflux procedure, resulting in a certain risk of iatrogenic gastroesophageal reflux disease (GERD). The aim of the present study was to evaluate the incidence of iatrogenic GERD after POEM and identify preoperative, perioperative and postoperative factors associated with GERD. All patients treated at a single center who had a complete GERD evaluation after POEM were included in the study. Demographics, preoperative and follow-up data, results of functional studies and procedural data were collected and analyzed. A total of 103 patients (mean age 46.6 years, 47 males) were included. Postoperative altered esophageal acid exposure was attested in 52 patients (50.5%). A total of 19 patients (18.4%) had heartburn and 21 had esophagitis (20.4%). Overall, a clinically relevant GERD (altered esophageal acid exposure, associated with heartburn and/or esophagitis) was diagnosed in 30 patients (29.1%). Correlation between the severity of esophageal acid exposure with heartburn and esophagitis after POEM was found. Patients with heartburn had a lower postoperative 4-second integrated relaxation pressure compared to patients without symptoms (7.6 ± 3.8 mmHg vs 10.01 ± 4.4 mmHg, p<0.05). No correlations were identified with patient sex, age, postoperative body mass index, esophageal shape (sigmoid vs non sigmoid), lower esophageal sphincter pressure, length of myotomy, previous therapies and type of achalasia at high-resolution manometry. Preoperative, perioperative or postoperative factors minimally correlated with GERD after POEM. Clinically relevant GERD was identified in less than one-third of patients, but all patients were well controlled with medical therapy. © 2015 The Authors Digestive Endoscopy © 2015 Japan Gastroenterological Endoscopy Society.

  20. 76 FR 37014 - Expedited Approval of Alternative Test Procedures for the Analysis of Contaminants Under the Safe...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-06-24

    ...; Analysis and Sampling Procedures AGENCY: Environmental Protection Agency (EPA). ACTION: Final rule. SUMMARY... Contaminants Under the Safe Drinking Water Act; Analysis and Sampling Procedures. 75 FR 32295. June 8, 2010...

  1. Research Methods and Data Analysis Procedures Used by Educational Researchers

    ERIC Educational Resources Information Center

    Hsu, Tse-chi

    2005-01-01

    To assess the status and the trends of subject matters investigated and research methods/designs and data analysis procedures employed by educational researchers, this study surveyed articles published by the "American Educational Research Journal (AERJ)," "Journal of Experimental Education (JEE)" and "Journal of Educational Research (JER)" from…

  2. Factors Affecting Utilization of Information Output of Computer-Based Modeling Procedures in Local Government Organizations.

    ERIC Educational Resources Information Center

    Komsky, Susan

    Fiscal Impact Budgeting Systems (FIBS) are sophisticated computer based modeling procedures used in local government organizations, whose results, however, are often overlooked or ignored by decision makers. A study attempted to discover the reasons for this situation by focusing on four factors: potential usefulness, faith in computers,…

  3. Analysis of helicopter noise data using international helicopter noise certification procedures

    DOT National Transportation Integrated Search

    1986-03-31

    This report documents the results of a Federal Aviation Administration (FAA) noise measurement flight test program involving seven helicopters and established noise levels using the basic testing, reduction and analysis procedures specified by the In...

  4. Stent-Assisted Coil Embolization of Vertebrobasilar Dissecting Aneurysms: Procedural Outcomes and Factors for Recanalization

    PubMed Central

    Jeon, Jin Pyeong; Rhim, Jong Kook; Park, Jeong Jin; Cho, Won-Sang; Kang, Hyun-Seung; Kim, Jeong Eun; Hwang, Gyojun; Kwon, O-Ki; Han, Moon Hee

    2016-01-01

    Objective Outcomes of stent-assisted coil embolization (SACE) have not been well established in the setting of vertebrobasilar dissecting aneurysms (VBDAs) due to the low percentage of cases that need treatment and the array of available therapeutic options. Herein, we presented clinical and radiographic results of SACE in patients with VBDAs. Materials and Methods A total of 47 patients (M:F, 30:17; mean age ± SD, 53.7 ± 12.6 years), with a VBDA who underwent SACE between 2008 and 2014 at two institutions were evaluated retrospectively. Medical records and radiologic data were analyzed to assess the outcome of SACE procedures. Cox proportional hazards regression analysis was conducted to determine the factors that were associated with aneurysmal recanalization after SACE. Results Stent-assisted coil embolization technically succeeded in all patients. Three cerebellar infarctions occurred on postembolization day 1, week 2, and month 2, but no other procedure-related complications developed. Immediately following SACE, 25 aneurysms (53.2%) showed no contrast filling into the aneurysmal sac. During a mean follow-up of 20.2 months, 37 lesions (78.7%) appeared completely occluded, whereas 10 lesions showed recanalization, 5 of which required additional embolization. Overall recanalization rate was 12.64% per lesion-year, and mean postoperative time to recanalization was 18 months (range, 3–36 months). In multivariable analysis, major branch involvement (hazard ratio [HR]: 7.28; p = 0.013) and the presence of residual sac filling (HR: 8.49, p = 0.044) were identified as statistically significant independent predictors of recanalization. No bleeding was encountered in follow-up monitoring. Conclusion Stent-assisted coil embolization appears feasible and safe for treatment of VBDAs. Long-term results were acceptable in a majority of patients studied, despite a relatively high rate of incomplete occlusion immediately after SACE. Major branch involvement and coiled

  5. Predictive Factors of Atelectasis Following Endoscopic Resection.

    PubMed

    Choe, Jung Wan; Jung, Sung Woo; Song, Jong Kyu; Shim, Euddeum; Choo, Ji Yung; Kim, Seung Young; Hyun, Jong Jin; Koo, Ja Seol; Yim, Hyung Joon; Lee, Sang Woo

    2016-01-01

    Atelectasis is one of the pulmonary complications associated with anesthesia. Little is known about atelectasis following endoscopic procedures under deep sedation. This study evaluated the frequency, risk factors, and clinical course of atelectasis after endoscopic resection. A total of 349 patients who underwent endoscopic resection of the upper gastrointestinal tract at a single academic tertiary referral center from March 2010 to October 2013 were enrolled. Baseline characteristics and clinical data were retrospectively reviewed from medical records. To identify atelectasis, we compared the chest radiography taken before and after the endoscopic procedure. Among the 349 patients, 68 (19.5 %) had newly developed atelectasis following endoscopic resection. In univariate logistic regression analysis, atelectasis correlated significantly with high body mass index, smoking, diabetes mellitus, procedure duration, size of lesion, and total amount of propofol. In multiple logistic regression analysis, body mass index, procedure duration, and total propofol amount were risk factors for atelectasis following endoscopic procedures. Of the 68 patients with atelectasis, nine patients developed fever, and six patients displayed pneumonic infiltration. The others had no symptoms related to atelectasis. The incidence of radiographic atelectasis following endoscopic resection was nearly 20 %. Obesity, procedural time, and amount of propofol were the significant risk factors for atelectasis following endoscopic procedure. Most cases of the atelectasis resolved spontaneously with no sequelae.

  6. Human Factors Analysis to Improve the Processing of Ares-1 Launch Vehicle

    NASA Technical Reports Server (NTRS)

    Stambolian, Damon B.; Dippolito, Gregory M.; Nyugen, Bao; Dischinger, Charles; Tran, Donald; Henderson, Gena; Barth, Tim

    2011-01-01

    This slide presentation reviews the use of Human Factors analysis in improving the ground processing procedures for the Ares-1 launch vehicle. The light vehicle engineering designers for Ares-l launch vehicle had to design the flight vehicle for effective, efficient and safe ground operations in the cramped dimensions in a rocket design. The use of a mockup of the area where the technician would be required to work proved to be a very effective method to promote the collaboration between the Ares-1 designers and the ground operations personnel.

  7. Exploratory Bi-factor Analysis: The Oblique Case.

    PubMed

    Jennrich, Robert I; Bentler, Peter M

    2012-07-01

    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 analysis that does not require one to provide an explicit bi-factor structure a priori. They use exploratory factor analysis and a bifactor rotation criterion designed to produce a rotated loading matrix that has an approximate bi-factor structure. Among other things this can be used as an aid in finding an explicit bi-factor structure for use in a confirmatory bi-factor analysis. They considered only orthogonal rotation. The purpose of this paper is to consider oblique rotation and to compare it to orthogonal rotation. Because there are many more oblique rotations of an initial loading matrix than orthogonal rotations, one expects the oblique results to approximate a bi-factor structure better than orthogonal rotations and this is indeed the case. A surprising result arises when oblique bi-factor rotation methods are applied to ideal data.

  8. Determining organisation-specific factors for developing health interventions in companies by a Delphi procedure: Organisational Mapping.

    PubMed

    van Scheppingen, Arjella R; ten Have, Kristin C J M; Zwetsloot, Gerard J I M; Kok, Gerjo; van Mechelen, Willem

    2015-12-01

    Companies, seen as social communities, are major health promotion contexts. However, health promotion in the work setting is often less successful than intended. An optimal adjustment to the organisational context is required. Knowledge of which organisation-specific factors are relevant to health promotion is scarce. A Delphi procedure is used to identify these factors. The aim is to contribute to more effective workplace health promotion. The identified factors are described and embedded into a practical methodology (Intervention Mapping). A systematic use of these factors (called 'Organisational Mapping') is likely to contribute to more effective health promotion in the work setting. © The Author(s) 2014.

  9. Human factors evaluation of remote afterloading brachytherapy. Volume 2, Function and task analysis

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

    Callan, J.R.; Gwynne, J.W. III; Kelly, T.T.

    1995-05-01

    A human factors project on the use of nuclear by-product material to treat cancer using remotely operated afterloaders was undertaken by the Nuclear Regulatory Commission. The purpose of the project was to identify factors that contribute to human error in the system for remote afterloading brachytherapy (RAB). This report documents the findings from the first phase of the project, which involved an extensive function and task analysis of RAB. This analysis identified the functions and tasks in RAB, made preliminary estimates of the likelihood of human error in each task, and determined the skills needed to perform each RAB task.more » The findings of the function and task analysis served as the foundation for the remainder of the project, which evaluated four major aspects of the RAB system linked to human error: human-system interfaces; procedures and practices; training and qualifications of RAB staff; and organizational practices and policies. At its completion, the project identified and prioritized areas for recommended NRC and industry attention based on all of the evaluations and analyses.« less

  10. Shrunken head (tsantsa): a complete forensic analysis procedure.

    PubMed

    Charlier, P; Huynh-Charlier, I; Brun, L; Hervé, C; de la Grandmaison, G Lorin

    2012-10-10

    Based on the analysis of shrunken heads referred to our forensic laboratory for anthropological expertise, and data from both anthropological and medical literature, we propose a complete forensic procedure for the analysis of such pieces. A list of 14 original morphological criteria has been developed, based on the global aspect, color, physical deformation, anatomical details, and eventual associated material (wood, vegetal fibers, sand, charcoals, etc.). Such criteria have been tested on a control sample of 20 tsantsa (i.e. shrunken heads from the Jivaro or Shuar tribes of South America). Further complementary analyses are described such as CT-scan and microscopic examination. Such expertise is more and more asked to forensic anthropologists and practitioners in a context of global repatriation of human artifacts to native communities. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  11. 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…

  12. Sampling factors influencing accuracy of sperm kinematic analysis.

    PubMed

    Owen, D H; Katz, D F

    1993-01-01

    Sampling conditions that influence the accuracy of experimental measurement of sperm head kinematics were studied by computer simulation methods. Several archetypal sperm trajectories were studied. First, mathematical models of typical flagellar beats were input to hydrodynamic equations of sperm motion. The instantaneous swimming velocities of such sperm were computed over sequences of flagellar beat cycles, from which the resulting trajectories were determined. In a second, idealized approach, direct mathematical models of trajectories were utilized, based upon similarities to the previous hydrodynamic constructs. In general, it was found that analyses of sampling factors produced similar results for the hydrodynamic and idealized trajectories. A number of experimental sampling factors were studied, including the number of sperm head positions measured per flagellar beat, and the time interval over which these measurements are taken. It was found that when one flagellar beat is sampled, values of amplitude of lateral head displacement (ALH) and linearity (LIN) approached their actual values when five or more sample points per beat were taken. Mean angular displacement (MAD) values, however, remained sensitive to sampling rate even when large sampling rates were used. Values of MAD were also much more sensitive to the initial starting point of the sampling procedure than were ALH or LIN. On the basis of these analyses of measurement accuracy for individual sperm, simulations were then performed of cumulative effects when studying entire populations of motile cells. It was found that substantial (double digit) errors occurred in the mean values of curvilinear velocity (VCL), LIN, and MAD under the conditions of 30 video frames per second and 0.5 seconds of analysis time. Increasing the analysis interval to 1 second did not appreciably improve the results. However, increasing the analysis rate to 60 frames per second significantly reduced the errors. These findings

  13. Test and analysis procedures for updating math models of Space Shuttle payloads

    NASA Technical Reports Server (NTRS)

    Craig, Roy R., Jr.

    1991-01-01

    Over the next decade or more, the Space Shuttle will continue to be the primary transportation system for delivering payloads to Earth orbit. Although a number of payloads have already been successfully carried by the Space Shuttle in the payload bay of the Orbiter vehicle, there continues to be a need for evaluation of the procedures used for verifying and updating the math models of the payloads. The verified payload math models is combined with an Orbiter math model for the coupled-loads analysis, which is required before any payload can fly. Several test procedures were employed for obtaining data for use in verifying payload math models and for carrying out the updating of the payload math models. Research was directed at the evaluation of test/update procedures for use in the verification of Space Shuttle payload math models. The following research tasks are summarized: (1) a study of free-interface test procedures; (2) a literature survey and evaluation of model update procedures; and (3) the design and construction of a laboratory payload simulator.

  14. Intracerebral hemorrhage after external ventricular drain placement: an evaluation of risk factors for post-procedural hemorrhagic complications.

    PubMed

    Rowe, A Shaun; Rinehart, Derrick R; Lezatte, Stephanie; Langdon, J Russell

    2018-03-07

    The objective of this study was to evaluate and identify the risk factors for developing a new or enlarged intracranial hemorrhage (ICH) after the placement of an external ventricular drain. A single center, nested case-control study of individuals who received an external ventricular drain from June 1, 2011 to June 30, 2014 was conducted at a large academic medical center. A bivariate analysis was conducted to compare those individuals who experienced a post-procedural intracranial hemorrhage to those who did not experience a new bleed. The variables identified as having a p-value less than 0.15 in the bivariate analysis were then evaluated using a multivariate logistic regression model. Twenty-seven of the eighty-one study participants experienced a new or enlarged intracranial hemorrhage after the placement of an external ventricular drain. Of these twenty-seven patients, 6 individuals received an antiplatelet within ninety-six hours of external ventricular drain placement (p = 0.024). The multivariate logistic regression model identified antiplatelet use within 96 h of external ventricular drain insertion as an independent risk factor for post-EVD ICH (OR 13.1; 95% CI 1.95-88.6; p = 0.008). Compared to those study participants who did not receive an antiplatelet within 96 h of external ventricular drain placement, those participants who did receive an antiplatelet were 13.1 times more likely to exhibit a new or enlarged intracranial hemorrhage.

  15. Failure mode and effects analysis: an empirical comparison of failure mode scoring procedures.

    PubMed

    Ashley, Laura; Armitage, Gerry

    2010-12-01

    To empirically compare 2 different commonly used failure mode and effects analysis (FMEA) scoring procedures with respect to their resultant failure mode scores and prioritization: a mathematical procedure, where scores are assigned independently by FMEA team members and averaged, and a consensus procedure, where scores are agreed on by the FMEA team via discussion. A multidisciplinary team undertook a Healthcare FMEA of chemotherapy administration. This included mapping the chemotherapy process, identifying and scoring failure modes (potential errors) for each process step, and generating remedial strategies to counteract them. Failure modes were scored using both an independent mathematical procedure and a team consensus procedure. Almost three-fifths of the 30 failure modes generated were scored differently by the 2 procedures, and for just more than one-third of cases, the score discrepancy was substantial. Using the Healthcare FMEA prioritization cutoff score, almost twice as many failure modes were prioritized by the consensus procedure than by the mathematical procedure. This is the first study to empirically demonstrate that different FMEA scoring procedures can score and prioritize failure modes differently. It found considerable variability in individual team members' opinions on scores, which highlights the subjective and qualitative nature of failure mode scoring. A consensus scoring procedure may be most appropriate for FMEA as it allows variability in individuals' scores and rationales to become apparent and to be discussed and resolved by the team. It may also yield team learning and communication benefits unlikely to result from a mathematical procedure.

  16. A Human Factors Analysis of Technical and Team Skills Among Surgical Trainees During Procedural Simulations in a Simulated Operating Theatre

    PubMed Central

    Moorthy, Krishna; Munz, Yaron; Adams, Sally; Pandey, Vikas; Darzi, Ara

    2005-01-01

    Background: High-risk organizations such as aviation rely on simulations for the training and assessment of technical and team performance. The aim of this study was to develop a simulated environment for surgical trainees using similar principles. Methods: A total of 27 surgical trainees carried out a simulated procedure in a Simulated Operating Theatre with a standardized OR team. Observation of OR events was carried out by an unobtrusive data collection system: clinical data recorder. Assessment of performance consisted of blinded rating of technical skills, a checklist of technical events, an assessment of communication, and a global rating of team skills by a human factors expert and trained surgical research fellows. The participants underwent a debriefing session, and the face validity of the simulated environment was evaluated. Results: While technical skills rating discriminated between surgeons according to experience (P = 0.002), there were no differences in terms of the checklist and team skills (P = 0.70). While all trainees were observed to gown/glove and handle sharps correctly, low scores were observed for some key features of communication with other team members. Low scores were obtained by the entire cohort for vigilance. Interobserver reliability was 0.90 and 0.89 for technical and team skills ratings. Conclusions: The simulated operating theatre could serve as an environment for the development of surgical competence among surgical trainees. Objective, structured, and multimodal assessment of performance during simulated procedures could serve as a basis for focused feedback during training of technical and team skills. PMID:16244534

  17. Motives for cosmetic procedures in Saudi women.

    PubMed

    Al-Natour, Sahar H

    2014-01-01

    The media-fuelled obsession with beauty in modern society has led more women to seek elective cosmetic procedures to meet the portrayed ideals of beauty in different cultures. This study gives insights into incentives and desires to undergo cosmetic procedures in a conservative society with strict religious practices where women are veiled. Questionnaire data were obtained from 509 Saudi women who responded to a survey distributed randomly to a sample of Saudi women aged 17 to 72 years. At least 1 elective cosmetic procedure was performed in 42% of the women, of whom 77.8% wore a veil. Another 33% considered having a procedure. The motives for seeking a cosmetic procedure were to improve self-esteem in 83.7%, attract a husband in 63.3%, or prevent a husband from seeking another wife in 36.2%. The decision to seek a procedure was affected by the media, with high peer influence. Motivation for elective cosmetic procedures in Saudi women is influenced by a combination of emotional and cultural factors, level of education, marital status, and religious beliefs. The veil is not an impediment for seeking such procedures. The limitation of the study was missing data analysis as some items in the questionnaire were completed inaccurately or left unanswered.

  18. A novel procedure on next generation sequencing data analysis using text mining algorithm.

    PubMed

    Zhao, Weizhong; Chen, James J; Perkins, Roger; Wang, Yuping; Liu, Zhichao; Hong, Huixiao; Tong, Weida; Zou, Wen

    2016-05-13

    Next-generation sequencing (NGS) technologies have provided researchers with vast possibilities in various biological and biomedical research areas. Efficient data mining strategies are in high demand for large scale comparative and evolutional studies to be performed on the large amounts of data derived from NGS projects. Topic modeling is an active research field in machine learning and has been mainly used as an analytical tool to structure large textual corpora for data mining. We report a novel procedure to analyse NGS data using topic modeling. It consists of four major procedures: NGS data retrieval, preprocessing, topic modeling, and data mining using Latent Dirichlet Allocation (LDA) topic outputs. The NGS data set of the Salmonella enterica strains were used as a case study to show the workflow of this procedure. The perplexity measurement of the topic numbers and the convergence efficiencies of Gibbs sampling were calculated and discussed for achieving the best result from the proposed procedure. The output topics by LDA algorithms could be treated as features of Salmonella strains to accurately describe the genetic diversity of fliC gene in various serotypes. The results of a two-way hierarchical clustering and data matrix analysis on LDA-derived matrices successfully classified Salmonella serotypes based on the NGS data. The implementation of topic modeling in NGS data analysis procedure provides a new way to elucidate genetic information from NGS data, and identify the gene-phenotype relationships and biomarkers, especially in the era of biological and medical big data. The implementation of topic modeling in NGS data analysis provides a new way to elucidate genetic information from NGS data, and identify the gene-phenotype relationships and biomarkers, especially in the era of biological and medical big data.

  19. An Exploratory Investigation of the Factor Structure of the Reynolds Intellectual Assessment Scales (RIAS)

    ERIC Educational Resources Information Center

    Dombrowski, Stefan C.; Watkins, Marley W.; Brogan, Michael J.

    2009-01-01

    This study investigated the factor structure of the Reynolds Intellectual Assessment Scales (RIAS) using rigorous exploratory factor analytic and factor extraction procedures. The results of this study indicate that the RIAS is a single factor test. Despite these results, higher order factor analysis using the Schmid-Leiman procedure indicates…

  20. Comparative study of procedures for the analysis of chloride in hardened concrete.

    DOT National Transportation Integrated Search

    1976-01-01

    In the widely used potentiometric titration procedure for the analysis of chloride in powdered hardened concrete samples, difficulties have often been encountered when determining the endpoint. These difficulties have been eliminated through the use ...

  1. Hierarchical Factor Structure of the Cognitive Assessment System: Variance Partitions from the Schmid-Leiman (1957) Procedure

    ERIC Educational Resources Information Center

    Canivez, Gary L.

    2011-01-01

    Orthogonal higher-order factor structure of the Cognitive Assessment System (CAS; Naglieri & Das, 1997a) for the 5-7 and 8-17 age groups in the CAS standardization sample is reported. Following the same procedure as recent studies of other prominent intelligence tests (Dombrowski, Watkins, & Brogan, 2009; Canivez, 2008; Canivez &…

  2. Postoperative central nervous system infection: incidence and associated factors in 2111 neurosurgical procedures.

    PubMed

    McClelland, Shearwood; Hall, Walter A

    2007-07-01

    Postoperative central nervous system infection (PCNSI) in patients undergoing neurosurgical procedures represents a serious problem that requires immediate attention. PCNSI most commonly manifests as meningitis, subdural empyema, and/or brain abscess. Recent studies (which have included a minimum of 1000 operations) have reported that the incidence of PCNSI after neurosurgical procedures is 5%-7%, and many physicians believe that the true incidence is even higher. To address this issue, we examined the incidence of PCNSI in a sizeable patient population. The medical records and postoperative courses for patients involved in 2111 neurosurgical procedures at our institution during 1991-2005 were reviewed retrospectively to determine the incidence of PCNSI, the identity of offending organisms, and the factors associated with infection. The median age of patients at the time of surgery was 45 years. Of the 1587 cranial operations, 14 (0.8%) were complicated by PCNSI, whereas none of the 32 peripheral nerve operations resulted in PCNSI. The remaining 492 operative cases involved spinal surgery, of which 2 (0.4%) were complicated by PCNSI. The overall incidence of PCNSI was 0.8% (occurring after 16 of 2111 operations); the incidence of bacterial meningitis was 0.3% (occurring after 4 of 1587 operations), and the incidence of brain abscess was 0.2% (occurring after 3 of 1587 operations). The most common offending organism was Staphylococcus aureus (8 cases; 50% of infections), followed by Propionibacterium acnes (4 cases; 25% of infections). Cerebrospinal fluid leakage, diabetes mellitus, and male sex were not associated with PCNSI (P>.05). In one of the largest neurosurgical studies to have investigated PCNSI, the incidence of infection after neurosurgical procedures was <1%--more than 6 times lower than that reported in recent series of comparable numerical size. Cerebrospinal fluid leak, diabetes mellitus, and male sex were not associated with an increased incidence of

  3. 78 FR 14457 - Guidelines Establishing Test Procedures for the Analysis of Pollutants Under the Clean Water Act...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-06

    ... Establishing Test Procedures for the Analysis of Pollutants Under the Clean Water Act; Analysis and Sampling... for use as an alternative oil and grease method. Some comments were specific to the sampling...-side comparison using the specific procedures (e.g. sampling frequency, number of samples, QA/QC, and...

  4. Factor analysis in optimization of formulation of high content uniformity tablets containing low dose active substance.

    PubMed

    Lukášová, Ivana; Muselík, Jan; Franc, Aleš; Goněc, Roman; Mika, Filip; Vetchý, David

    2017-11-15

    Warfarin is intensively discussed drug with narrow therapeutic range. There have been cases of bleeding attributed to varying content or altered quality of the active substance. Factor analysis is useful for finding suitable technological parameters leading to high content uniformity of tablets containing low amount of active substance. The composition of tabletting blend and technological procedure were set with respect to factor analysis of previously published results. The correctness of set parameters was checked by manufacturing and evaluation of tablets containing 1-10mg of warfarin sodium. The robustness of suggested technology was checked by using "worst case scenario" and statistical evaluation of European Pharmacopoeia (EP) content uniformity limits with respect to Bergum division and process capability index (Cpk). To evaluate the quality of active substance and tablets, dissolution method was developed (water; EP apparatus II; 25rpm), allowing for statistical comparison of dissolution profiles. Obtained results prove the suitability of factor analysis to optimize the composition with respect to batches manufactured previously and thus the use of metaanalysis under industrial conditions is feasible. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. 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…

  6. Analysis of spatio-temporal variability of C-factor derived from remote sensing data

    NASA Astrophysics Data System (ADS)

    Pechanec, Vilem; Benc, Antonin; Purkyt, Jan; Cudlin, Pavel

    2016-04-01

    In some risk areas water erosion as the present task has got the strong influence on agriculture and can threaten inhabitants. In our country combination of USLE and RUSLE models has been used for water erosion assessment (Krása et al., 2013). Role of vegetation cover is characterized by the help of vegetation protection factor, so-called C- factor. Value of C-factor is given by the ratio of washing-off on a plot with arable crops to standard plot which is kept as fallow regularly spud after any rain (Janeček et al., 2012). Under conditions we cannot identify crop structure and its turn, determination of C-factor can be problem in large areas. In such case we only determine C-factor according to the average crop representation. New technologies open possibilities for acceleration and specification of the approach. Present-day approach for the C-factor determination is based on the analysis of multispectral image data. Red and infrared spectrum is extracted and these parts of image are used for computation of vegetation index series (NDVI, TSAVI). Acquired values for fractional time sections (during vegetation period) are averaged out. At the same time values of vegetation indices for a forest and cleared area are determined. Also regressive coefficients are computed. Final calculation is done by the help of regressive equations expressing relation between values of NDVI and C-factor (De Jong, 1994; Van der Knijff, 1999; Karaburun, 2010). Up-to-date land use layer is used for the determination of erosion threatened areas on the base of selection of individual landscape segments of erosion susceptible categories of land use. By means of Landsat 7 data C-factor has been determined for the whole area of the Czech Republic in every month of the year of 2014. At the model area in a small watershed C-factor has been determined by the conventional (tabular) procedure. Analysis was focused on: i) variability assessment of C-factor values while using the conventional

  7. Robust Bayesian Factor Analysis

    ERIC Educational Resources Information Center

    Hayashi, Kentaro; Yuan, Ke-Hai

    2003-01-01

    Bayesian factor analysis (BFA) assumes the normal distribution of the current sample conditional on the parameters. Practical data in social and behavioral sciences typically have significant skewness and kurtosis. If the normality assumption is not attainable, the posterior analysis will be inaccurate, although the BFA depends less on the current…

  8. Lead-Dependent Infective Endocarditis: The Role of Factors Predisposing to Its Development in an Analysis of 414 Clinical Cases.

    PubMed

    Polewczyk, Anna; Jacheć, Wojciech; Janion, Marianna; Podlaski, Rafał; Kutarski, Andrzej

    2015-07-01

    Lead-dependent infective endocarditis (LDIE) is a serious and insidious infective disease spreading along the leads to valve leaflets and endocardial surface. LDIE is still a lesser known disease with unclear risk factors, most often evaluated jointly for all infectious complications. Clinical data from 414 patients with the diagnosis of LDIE according to the Modified Duke Leads Criteria were analyzed. Patients with LDIE were identified in a population of 1,426 subjects submitted to transvenous lead extraction (TLE) in the Reference Center on Lead Extraction in Lublin, Poland, between March 2006 and July 2013 due to infectious (619 patients-43.4%) and noninfectious (807-56.6% of patients) reasons. During the period of 2006-2011, the analysis was conducted retrospectively; from early 2012 on, patients were enrolled prospectively. The effect of potential risk factors on the development of the disease was evaluated in a comparative analysis of clinical data from the LDIE patients and from 807 subjects with noninfectious indications for TLE. Additionally, in order to identify the factors predisposing to the development of LDIE, the population of infectious patients was divided into three subgroups: with isolated LDIE (157 patients), with LDIE and pocket infection (PI; 257 patients), and with isolated PI (205 patients). The groups and subgroups were analyzed for the presence of patient-dependent risk factors (age, gender, accompanying diseases, anticoagulation, or antiplatelet therapy) and procedure-related risk factors (the number and lead dwell time, pacing system, prior procedures, lead loops, and intracardiac abrasion of the leads). Furthermore, microbes' identification was conducted. The LDIE patients were older (67.3 vs 62.3; P = 0.001) and were more frequently male (68.6% vs 55.0%; P = 0.001) as compared with patients submitted to TLE for noninfectious reasons, but not in comparison with subjects diagnosed with isolated LDIE. In univariate analysis, the

  9. Bilateral effects of hospital patient-safety procedures on nurses' job satisfaction.

    PubMed

    Inoue, T; Karima, R; Harada, K

    2017-09-01

    The aim of this study was to examine how hospital patient-safety procedures affect the job satisfaction of hospital nurses. Additionally, we investigated the association between perceived autonomy and hospital patient-safety procedures and job satisfaction. Recently, measures for patient safety have been recognized as an essential requirement in hospitals. Hospital patient-safety procedures may enhance the job satisfaction of nurses by improving the quality of their work. However, such procedures may also decrease their job satisfaction by imposing excessive stress on nurses because they cannot make mistakes. The participants included 537 nurses at 10 private hospitals in Japan (The surveys were collected from March to July 2012). Factors related to hospital patient-safety procedures were demonstrated using factor analysis, and the associations between these factors and nurses' self-perceived autonomy and job satisfaction were examined using structural equation modelling. Five factors regarding hospital patient-safety procedures were extracted. Additionally, structural equation modelling revealed statistically significant associations between these factors and the nurses' self-perceived autonomy and job satisfaction. The findings showed that nurses' perceived autonomy of the workplace enhanced their job satisfaction and that their perceptions of hospital patient-safety procedures promoted their job satisfaction. However, some styles of chief nurses' leadership regarding patient safety restrict nurses' independent and autonomous decision-making and actions, resulting in a lowering of job satisfaction. This study demonstrated that hospital patient-safety procedures have ambiguous effects on nurses' job satisfaction. In particular, chief nurses' leadership relating to patient safety can have a positive or negative effect on nurses' job satisfaction. The findings indicated that hospital managers should demonstrate positive attitudes to improve patient safety for

  10. A Procedure for the Computerized Analysis of Cleft Palate Speech Transcription

    ERIC Educational Resources Information Center

    Fitzsimons, David A.; Jones, David L.; Barton, Belinda; North, Kathryn N.

    2012-01-01

    The phonetic symbols used by speech-language pathologists to transcribe speech contain underlying hexadecimal values used by computers to correctly display and process transcription data. This study aimed to develop a procedure to utilise these values as the basis for subsequent computerized analysis of cleft palate speech. A computer keyboard…

  11. Individual and population pharmacokinetic compartment analysis: a graphic procedure for quantification of predictive performance.

    PubMed

    Eksborg, Staffan

    2013-01-01

    Pharmacokinetic studies are important for optimizing of drug dosing, but requires proper validation of the used pharmacokinetic procedures. However, simple and reliable statistical methods suitable for evaluation of the predictive performance of pharmacokinetic analysis are essentially lacking. The aim of the present study was to construct and evaluate a graphic procedure for quantification of predictive performance of individual and population pharmacokinetic compartment analysis. Original data from previously published pharmacokinetic compartment analyses after intravenous, oral, and epidural administration, and digitized data, obtained from published scatter plots of observed vs predicted drug concentrations from population pharmacokinetic studies using the NPEM algorithm and NONMEM computer program and Bayesian forecasting procedures, were used for estimating the predictive performance according to the proposed graphical method and by the method of Sheiner and Beal. The graphical plot proposed in the present paper proved to be a useful tool for evaluation of predictive performance of both individual and population compartment pharmacokinetic analysis. The proposed method is simple to use and gives valuable information concerning time- and concentration-dependent inaccuracies that might occur in individual and population pharmacokinetic compartment analysis. Predictive performance can be quantified by the fraction of concentration ratios within arbitrarily specified ranges, e.g. within the range 0.8-1.2.

  12. Procedure-related risk of miscarriage following amniocentesis and chorionic villus sampling: a systematic review and meta-analysis.

    PubMed

    Akolekar, R; Beta, J; Picciarelli, G; Ogilvie, C; D'Antonio, F

    2015-01-01

    To estimate procedure-related risks of miscarriage following amniocentesis and chorionic villus sampling (CVS) based on a systematic review of the literature and a meta-analysis. A search of MEDLINE, EMBASE, CINHAL and The Cochrane Library (2000-2014) was performed to review relevant citations reporting procedure-related complications of amniocentesis and CVS. Only studies reporting data on more than 1000 procedures were included in this review to minimize the effect of bias from smaller studies. Heterogeneity between studies was estimated using Cochran's Q, the I(2) statistic and Egger bias. Meta-analysis of proportions was used to derive weighted pooled estimates for the risk of miscarriage before 24 weeks' gestation. Incidence-rate difference meta-analysis was used to estimate pooled procedure-related risks. The weighted pooled risks of miscarriage following invasive procedures were estimated from analysis of controlled studies including 324 losses in 42 716 women who underwent amniocentesis and 207 losses in 8899 women who underwent CVS. The risk of miscarriage prior to 24 weeks in women who underwent amniocentesis and CVS was 0.81% (95% CI, 0.58-1.08%) and 2.18% (95% CI, 1.61-2.82%), respectively. The background rates of miscarriage in women from the control group that did not undergo any procedures were 0.67% (95% CI, 0.46-0.91%) for amniocentesis and 1.79% (95% CI, 0.61-3.58%) for CVS. The weighted pooled procedure-related risks of miscarriage for amniocentesis and CVS were 0.11% (95% CI, -0.04 to 0.26%) and 0.22% (95% CI, -0.71 to 1.16%), respectively. The procedure-related risks of miscarriage following amniocentesis and CVS are much lower than are currently quoted. Copyright © 2014 ISUOG. Published by John Wiley & Sons Ltd.

  13. Procedure for analysis and design of weaving sections : volume 2, users guide.

    DOT National Transportation Integrated Search

    1983-12-01

    This research was performed to complete and advance the status of recently developed procedures for analysis and design of weaving sections (known as the Leisch method and-initially published in the 1979 issue of ITE Journal). The objective was to en...

  14. Risk factors for impaired respiratory function during nurse-administered procedural sedation and analgesia in the cardiac catheterisation laboratory: a matched case-control study.

    PubMed

    Conway, Aaron; Page, Karen; Rolley, John; Fulbrook, Paul

    2013-08-01

    Side effects of the medications used for procedural sedation and analgesia in the cardiac catheterisation laboratory are known to cause impaired respiratory function. Impaired respiratory function poses considerable risk to patient safety as it can lead to inadequate oxygenation. Having knowledge about the conditions that predict impaired respiratory function prior to the procedure would enable nurses to identify at-risk patients and selectively implement intensive respiratory monitoring. This would reduce the possibility of inadequate oxygenation occurring. To identify pre-procedure risk factors for impaired respiratory function during nurse-administered procedural sedation and analgesia in the cardiac catheterisation laboratory. Retrospective matched case-control. 21 cases of impaired respiratory function were identified and matched to 113 controls from a consecutive cohort of patients over 18 years of age. Conditional logistic regression was used to identify risk factors for impaired respiratory function. With each additional indicator of acute illness, case patients were nearly two times more likely than their controls to experience impaired respiratory function (OR 1.78; 95% CI 1.19-2.67; p = 0.005). Indicators of acute illness included emergency admission, being transferred from a critical care unit for the procedure or requiring respiratory or haemodynamic support in the lead up to the procedure. Several factors that predict the likelihood of impaired respiratory function were identified. The results from this study could be used to inform prospective studies investigating the effectiveness of interventions for impaired respiratory function during nurse-administered procedural sedation and analgesia in the cardiac catheterisation laboratory.

  15. Trust, confidence, procedural fairness, outcome fairness, moral conviction, and the acceptance of GM field experiments.

    PubMed

    Siegrist, Michael; Connor, Melanie; Keller, Carmen

    2012-08-01

    In 2005, Swiss citizens endorsed a moratorium on gene technology, resulting in the prohibition of the commercial cultivation of genetically modified crops and the growth of genetically modified animals until 2013. However, scientific research was not affected by this moratorium, and in 2008, GMO field experiments were conducted that allowed us to examine the factors that influence their acceptance by the public. In this study, trust and confidence items were analyzed using principal component analysis. The analysis revealed the following three factors: "economy/health and environment" (value similarity based trust), "trust and honesty of industry and scientists" (value similarity based trust), and "competence" (confidence). The results of a regression analysis showed that all the three factors significantly influenced the acceptance of GM field experiments. Furthermore, risk communication scholars have suggested that fairness also plays an important role in the acceptance of environmental hazards. We, therefore, included measures for outcome fairness and procedural fairness in our model. However, the impact of fairness may be moderated by moral conviction. That is, fairness may be significant for people for whom GMO is not an important issue, but not for people for whom GMO is an important issue. The regression analysis showed that, in addition to the trust and confidence factors, moral conviction, outcome fairness, and procedural fairness were significant predictors. The results suggest that the influence of procedural fairness is even stronger for persons having high moral convictions compared with persons having low moral convictions. © 2012 Society for Risk Analysis.

  16. Impact of resident participation on morbidity and mortality in neurosurgical procedures: an analysis of 16,098 patients.

    PubMed

    Bydon, Mohamad; Abt, Nicholas B; De la Garza-Ramos, Rafael; Macki, Mohamed; Witham, Timothy F; Gokaslan, Ziya L; Bydon, Ali; Huang, Judy

    2015-04-01

    mortality and morbidity; however, these cases also involved patients with more comorbidities initially. On multivariate analysis, resident participation was not an independent risk factor for postoperative 30-day morbidity or mortality following elective or emergent neurosurgical procedures.

  17. Impacts of biological and procedural factors on semiquantification uptake value of liver in fluorine-18 fluorodeoxyglucose positron emission tomography/computed tomography imaging.

    PubMed

    Mahmud, Mohd Hafizi; Nordin, Abdul Jalil; Ahmad Saad, Fathinul Fikri; Azman, Ahmad Zaid Fattah

    2015-10-01

    Increased metabolic activity of fluorodeoxyglucose (FDG) in tissue is not only resulting of pathological uptake, but due to physiological uptake as well. This study aimed to determine the impacts of biological and procedural factors on FDG uptake of liver in whole body positron emission tomography/computed tomography (PET/CT) imaging. Whole body fluorine-18 ((18)F) FDG PET/CT scans of 51 oncology patients have been reviewed. Maximum standardized uptake value (SUVmax) of lesion-free liver was quantified in each patient. Pearson correlation was performed to determine the association between the factors of age, body mass index (BMI), blood glucose level, FDG dose and incubation period and liver SUVmax. Multivariate regression analysis was established to determine the significant factors that best predicted the liver SUVmax. Then the subjects were dichotomised into four BMI groups. Analysis of variance (ANOVA) was established for mean difference of SUVmax of liver between those BMI groups. BMI and incubation period were significantly associated with liver SUVmax. These factors were accounted for 29.6% of the liver SUVmax variance. Statistically significant differences were observed in the mean SUVmax of liver among those BMI groups (P<0.05). BMI and incubation period are significant factors affecting physiological FDG uptake of liver. It would be recommended to employ different cut-off value for physiological liver SUVmax as a reference standard for different BMI of patients in PET/CT interpretation and use a standard protocol for incubation period of patient to reduce variation in physiological FDG uptake of liver in PET/CT study.

  18. 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…

  19. The Analysis of Rates of Naval Compensation by the Use of a Structured Job Analysis Procedure.

    ERIC Educational Resources Information Center

    Harris, Alma F.; McCormick, Ernest J.

    The study deals with the experimental application of a structured job analysis procedure to enlisted and officer billets in the Navy, with particular reference to its potential use in relating naval compensation for billet incumbents to compensation for civilian jobs with similar characteristics, and in assessing its utility for allocating naval…

  20. Statistical analysis of the calibration procedure for personnel radiation measurement instruments

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

    Bush, W.J.; Bengston, S.J.; Kalbeitzer, F.L.

    1980-11-01

    Thermoluminescent analyzer (TLA) calibration procedures were used to estimate personnel radiation exposure levels at the Idaho National Engineering Laboratory (INEL). A statistical analysis is presented herein based on data collected over a six month period in 1979 on four TLA's located in the Department of Energy (DOE) Radiological and Environmental Sciences Laboratory at the INEL. The data were collected according to the day-to-day procedure in effect at that time. Both gamma and beta radiation models are developed. Observed TLA readings of thermoluminescent dosimeters are correlated with known radiation levels. This correlation is then used to predict unknown radiation doses frommore » future analyzer readings of personnel thermoluminescent dosimeters. The statistical techniques applied in this analysis include weighted linear regression, estimation of systematic and random error variances, prediction interval estimation using Scheffe's theory of calibration, the estimation of the ratio of the means of two normal bivariate distributed random variables and their corresponding confidence limits according to Kendall and Stuart, tests of normality, experimental design, a comparison between instruments, and quality control.« less

  1. Impact of Anatomical, Procedural, and Operator Skill Factors on the Success and Duration of Fluoroscopy-Guided Transjugular Intrahepatic Portosystemic Shunt

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

    Marquardt, Steffen, E-mail: marquardt.steffen@mh-hannover.de; Rodt, Thomas, E-mail: rodt.thomas@mh-hannover.de; Rosenthal, Herbert, E-mail: rosenthal.herbert@mh-hannover.de

    PurposeTo assess the impact of anatomical, procedural, and operator skill factors on the success and duration of fluoroscopy-guided transjugular intrahepatic portoystemic shunt following standard operating procedure (SOP).Material and MethodsDuring a 32-month period, 102 patients underwent transjugular intrahepatic portosystemic shunt creation (TIPS) by two interventional radiologists (IR) following our institutional SOP based on fluoroscopy guidance. Both demographic and procedural data were assessed. The duration of the intervention (D{sub Int}) and of the portal vein puncture (D{sub Punct}) was analyzed depending on the skill level of the IR as well as the anatomic or procedural factors.ResultsIn 99 of the 102 patients, successfulmore » TIPS without peri-procedural complications was performed. The mean D{sub Int} (IR1: 77 min; IR2: 51 min, P < 0.005) and the mean D{sub Punct} (IR1: 19 min; IR2: 13 min, P < 0.005) were significantly higher in TIPS performed by IR1 (with 2 years of clinical experience performing TIPS, n = 38) than by IR2 (>10 years of clinical experience performing TIPS, n = 61), (P < 0.005 both, Mann–Whitney U test). D{sub Int} showed a higher correlation with D{sub Punct} for IR2 (R{sup 2} = 0.63) than for IR1 (R{sup 2} = 0.13). There was no significant difference in the D{sub Punct} for both IRs with regard to the success of the wedged portography (P = 0.90), diameter of the portal vein (P = 0.60), central right portal vein length (P = 0.49), or liver function (MELD-Score before the TIPS procedure; P = 0.14).ConclusionTIPS following SOP is safe, fast, and reliable. The only significant factor for shorter D{sub Punct} and D{sub Int} was the clinical experience of the IR. Anatomic variability, successful portography, or liver function did not alter the duration or technical success of TIPS.« less

  2. Development of a thermal and structural analysis procedure for cooled radial turbines

    NASA Technical Reports Server (NTRS)

    Kumar, Ganesh N.; Deanna, Russell G.

    1988-01-01

    A procedure for computing the rotor temperature and stress distributions in a cooled radial turbine are considered. Existing codes for modeling the external mainstream flow and the internal cooling flow are used to compute boundary conditions for the heat transfer and stress analysis. The inviscid, quasi three dimensional code computes the external free stream velocity. The external velocity is then used in a boundary layer analysis to compute the external heat transfer coefficients. Coolant temperatures are computed by a viscous three dimensional internal flow cade for the momentum and energy equation. These boundary conditions are input to a three dimensional heat conduction code for the calculation of rotor temperatures. The rotor stress distribution may be determined for the given thermal, pressure and centrifugal loading. The procedure is applied to a cooled radial turbine which will be tested at the NASA Lewis Research Center. Representative results are given.

  3. Expected p-values in light of an ROC curve analysis applied to optimal multiple testing procedures.

    PubMed

    Vexler, Albert; Yu, Jihnhee; Zhao, Yang; Hutson, Alan D; Gurevich, Gregory

    2017-01-01

    Many statistical studies report p-values for inferential purposes. In several scenarios, the stochastic aspect of p-values is neglected, which may contribute to drawing wrong conclusions in real data experiments. The stochastic nature of p-values makes their use to examine the performance of given testing procedures or associations between investigated factors to be difficult. We turn our focus on the modern statistical literature to address the expected p-value (EPV) as a measure of the performance of decision-making rules. During the course of our study, we prove that the EPV can be considered in the context of receiver operating characteristic (ROC) curve analysis, a well-established biostatistical methodology. The ROC-based framework provides a new and efficient methodology for investigating and constructing statistical decision-making procedures, including: (1) evaluation and visualization of properties of the testing mechanisms, considering, e.g. partial EPVs; (2) developing optimal tests via the minimization of EPVs; (3) creation of novel methods for optimally combining multiple test statistics. We demonstrate that the proposed EPV-based approach allows us to maximize the integrated power of testing algorithms with respect to various significance levels. In an application, we use the proposed method to construct the optimal test and analyze a myocardial infarction disease dataset. We outline the usefulness of the "EPV/ROC" technique for evaluating different decision-making procedures, their constructions and properties with an eye towards practical applications.

  4. Exploratory factor analysis in Rehabilitation Psychology: a content analysis.

    PubMed

    Roberson, Richard B; Elliott, Timothy R; Chang, Jessica E; Hill, Jessica N

    2014-11-01

    Our objective was to examine the use and quality of exploratory factor analysis (EFA) in articles published in Rehabilitation Psychology. Trained raters examined 66 separate exploratory factor analyses in 47 articles published between 1999 and April 2014. The raters recorded the aim of the EFAs, the distributional statistics, sample size, factor retention method(s), extraction and rotation method(s), and whether the pattern coefficients, structure coefficients, and the matrix of association were reported. The primary use of the EFAs was scale development, but the most widely used extraction and rotation method was principle component analysis, with varimax rotation. When determining how many factors to retain, multiple methods (e.g., scree plot, parallel analysis) were used most often. Many articles did not report enough information to allow for the duplication of their results. EFA relies on authors' choices (e.g., factor retention rules extraction, rotation methods), and few articles adhered to all of the best practices. The current findings are compared to other empirical investigations into the use of EFA in published research. Recommendations for improving EFA reporting practices in rehabilitation psychology research are provided.

  5. Performance analysis of a generalized upset detection procedure

    NASA Technical Reports Server (NTRS)

    Blough, Douglas M.; Masson, Gerald M.

    1987-01-01

    A general procedure for upset detection in complex systems, called the data block capture and analysis upset monitoring process is described and analyzed. The process consists of repeatedly recording a fixed amount of data from a set of predetermined observation lines of the system being monitored (i.e., capturing a block of data), and then analyzing the captured block in an attempt to determine whether the system is functioning correctly. The algorithm which analyzes the data blocks can be characterized in terms of the amount of time it requires to examine a given length data block to ascertain the existence of features/conditions that have been predetermined to characterize the upset-free behavior of the system. The performance of linear, quadratic, and logarithmic data analysis algorithms is rigorously characterized in terms of three performance measures: (1) the probability of correctly detecting an upset; (2) the expected number of false alarms; and (3) the expected latency in detecting upsets.

  6. Weather analysis and interpretation procedures developed for the US/Canada wheat and barley exploratory experiment

    NASA Technical Reports Server (NTRS)

    Trenchard, M. H. (Principal Investigator)

    1980-01-01

    Procedures and techniques for providing analyses of meteorological conditions at segments during the growing season were developed for the U.S./Canada Wheat and Barley Exploratory Experiment. The main product and analysis tool is the segment-level climagraph which depicts temporally meteorological variables for the current year compared with climatological normals. The variable values for the segment are estimates derived through objective analysis of values obtained at first-order station in the region. The procedures and products documented represent a baseline for future Foreign Commodity Production Forecasting experiments.

  7. Estimation of the behavior factor of existing RC-MRF buildings

    NASA Astrophysics Data System (ADS)

    Vona, Marco; Mastroberti, Monica

    2018-01-01

    In recent years, several research groups have studied a new generation of analysis methods for seismic response assessment of existing buildings. Nevertheless, many important developments are still needed in order to define more reliable and effective assessment procedures. Moreover, regarding existing buildings, it should be highlighted that due to the low knowledge level, the linear elastic analysis is the only analysis method allowed. The same codes (such as NTC2008, EC8) consider the linear dynamic analysis with behavior factor as the reference method for the evaluation of seismic demand. This type of analysis is based on a linear-elastic structural model subject to a design spectrum, obtained by reducing the elastic spectrum through a behavior factor. The behavior factor (reduction factor or q factor in some codes) is used to reduce the elastic spectrum ordinate or the forces obtained from a linear analysis in order to take into account the non-linear structural capacities. The behavior factors should be defined based on several parameters that influence the seismic nonlinear capacity, such as mechanical materials characteristics, structural system, irregularity and design procedures. In practical applications, there is still an evident lack of detailed rules and accurate behavior factor values adequate for existing buildings. In this work, some investigations of the seismic capacity of the main existing RC-MRF building types have been carried out. In order to make a correct evaluation of the seismic force demand, actual behavior factor values coherent with force based seismic safety assessment procedure have been proposed and compared with the values reported in the Italian seismic code, NTC08.

  8. From Laser Scanning to Finite Element Analysis of Complex Buildings by Using a Semi-Automatic Procedure.

    PubMed

    Castellazzi, Giovanni; D'Altri, Antonio Maria; Bitelli, Gabriele; Selvaggi, Ilenia; Lambertini, Alessandro

    2015-07-28

    In this paper, a new semi-automatic procedure to transform three-dimensional point clouds of complex objects to three-dimensional finite element models is presented and validated. The procedure conceives of the point cloud as a stacking of point sections. The complexity of the clouds is arbitrary, since the procedure is designed for terrestrial laser scanner surveys applied to buildings with irregular geometry, such as historical buildings. The procedure aims at solving the problems connected to the generation of finite element models of these complex structures by constructing a fine discretized geometry with a reduced amount of time and ready to be used with structural analysis. If the starting clouds represent the inner and outer surfaces of the structure, the resulting finite element model will accurately capture the whole three-dimensional structure, producing a complex solid made by voxel elements. A comparison analysis with a CAD-based model is carried out on a historical building damaged by a seismic event. The results indicate that the proposed procedure is effective and obtains comparable models in a shorter time, with an increased level of automation.

  9. Four points function fitted and first derivative procedure for determining the end points in potentiometric titration curves: statistical analysis and method comparison.

    PubMed

    Kholeif, S A

    2001-06-01

    A new method that belongs to the differential category for determining the end points from potentiometric titration curves is presented. It uses a preprocess to find first derivative values by fitting four data points in and around the region of inflection to a non-linear function, and then locate the end point, usually as a maximum or minimum, using an inverse parabolic interpolation procedure that has an analytical solution. The behavior and accuracy of the sigmoid and cumulative non-linear functions used are investigated against three factors. A statistical evaluation of the new method using linear least-squares method validation and multifactor data analysis are covered. The new method is generally applied to symmetrical and unsymmetrical potentiometric titration curves, and the end point is calculated using numerical procedures only. It outperforms the "parent" regular differential method in almost all factors levels and gives accurate results comparable to the true or estimated true end points. Calculated end points from selected experimental titration curves compatible with the equivalence point category of methods, such as Gran or Fortuin, are also compared with the new method.

  10. Analysis of In Vivo Chromatin and Protein Interactions of Arabidopsis Transcript Elongation Factors.

    PubMed

    Pfab, Alexander; Antosz, Wojciech; Holzinger, Philipp; Bruckmann, Astrid; Griesenbeck, Joachim; Grasser, Klaus D

    2017-01-01

    A central step to elucidate the function of proteins commonly comprises the analysis of their molecular interactions in vivo. For nuclear regulatory proteins this involves determining protein-protein interactions as well as mapping of chromatin binding sites. Here, we present two protocols to identify protein-protein and chromatin interactions of transcript elongation factors (TEFs) in Arabidopsis. The first protocol (Subheading 3.1) describes protein affinity-purification coupled to mass spectrometry (AP-MS) that utilizes suspension cultured cells as experimental system. This approach provides an unbiased view of proteins interacting with epitope-tagged TEFs. The second protocol (Subheading 3.2) depicts details about a chromatin immunoprecipitation (ChIP) procedure to characterize genomic binding sites of TEFs. These methods should be valuable tools for the analysis of a broad variety of nuclear proteins.

  11. Risk factor and cost accounting analysis for dialysis patients in Taiwan.

    PubMed

    Su, Bin-Guang; Tsai, Kai-Li; Yeh, Shu-Hsing; Ho, Yi-Yi; Liu, Shin-Yi; Rivers, Patrick A

    2010-05-01

    with high blood lipids incurred significant differences in cost of oral medication. This study identified the relationship between cost and risk factors of dialysis procedures for ESRD patients based on average variable costs for each dialysis treatment. The results show that certain risk factors (e.g. aged 75 and older, hypertension, bile-duct disease, cancer and high blood lipids) are associated with higher cost. The results from this study could enable health policy makers and the National Health Insurance Bureau to design a fairer and more convincible reimbursement system for dialysis procedures. This study also provides a better understanding of what risk factors play more influential roles in affecting ESRD patients to receive haemodialysis treatment. It will help policy makers and health-care providers in better control or even prevent the disease and manage the distribution of the treatment. In addition, with the results from the analysis of cost information, we can tell which risk factors have more impacts on the dialysis cost. It will further help us control the cost for those high-risk dialysis patients more efficiently.

  12. Effectiveness of internet-based affect induction procedures: A systematic review and meta-analysis.

    PubMed

    Ferrer, Rebecca A; Grenen, Emily G; Taber, Jennifer M

    2015-12-01

    Procedures used to induce affect in a laboratory are effective and well-validated. Given recent methodological and technological advances in Internet research, it is important to determine whether affect can be effectively induced using Internet methodology. We conducted a meta-analysis and systematic review of prior research that has used Internet-based affect induction procedures, and examined potential moderators of the effectiveness of affect induction procedures. Twenty-six studies were included in final analyses, with 89 independent effect sizes. Affect induction procedures effectively induced general positive affect, general negative affect, fear, disgust, anger, sadness, and guilt, but did not significantly induce happiness. Contamination of other nontarget affect did not appear to be a major concern. Video inductions resulted in greater effect sizes. Overall, results indicate that affect can be effectively induced in Internet studies, suggesting an important venue for the acceleration of affective science. (PsycINFO Database Record (c) 2015 APA, all rights reserved).

  13. Factor analysis of social skills inventory responses of Italians and Americans.

    PubMed

    Galeazzi, Aldo; Franceschina, Emilio; Holmes, George R

    2002-06-01

    The Social Skills Inventory is a 90-item self-report procedure designed to measure social and communication skills. The inventory measures six dimensions, namely, Emotional Expressivity, Emotional Sensitivity, Emotional Control, Social Expressivity, Social Sensitivity, and Social Control. The Italian version was administered in several cities in Northern Italy to 500 Italian participants ranging in age from 15 to 59 years. Factor analysis appears to confirm the adequacy of the inventory for the Italian adult population. Results indicate strong similarities between the Italian and American populations with respect to the measure of social skills. Indexes of internal reliability and test-retest reliability are good for almost all subscales of the inventory, which should encourage the use of this inventory with Italian samples.

  14. Uncertainty Analysis of A Flood Risk Mapping Procedure Applied In Urban Areas

    NASA Astrophysics Data System (ADS)

    Krause, J.; Uhrich, S.; Bormann, H.; Diekkrüger, B.

    In the framework of IRMA-Sponge program the presented study was part of the joint research project FRHYMAP (flood risk and hydrological mapping). A simple con- ceptual flooding model (FLOODMAP) has been developed to simulate flooded areas besides rivers within cities. FLOODMAP requires a minimum of input data (digital el- evation model (DEM), river line, water level plain) and parameters and calculates the flood extent as well as the spatial distribution of flood depths. of course the simulated model results are affected by errors and uncertainties. Possible sources of uncertain- ties are the model structure, model parameters and input data. Thus after the model validation (comparison of simulated water to observed extent, taken from airborne pictures) the uncertainty of the essential input data set (digital elevation model) was analysed. Monte Carlo simulations were performed to assess the effect of uncertain- ties concerning the statistics of DEM quality and to derive flooding probabilities from the set of simulations. The questions concerning a minimum resolution of a DEM re- quired for flood simulation and concerning the best aggregation procedure of a given DEM was answered by comparing the results obtained using all available standard GIS aggregation procedures. Seven different aggregation procedures were applied to high resolution DEMs (1-2m) in three cities (Bonn, Cologne, Luxembourg). Basing on this analysis the effect of 'uncertain' DEM data was estimated and compared with other sources of uncertainties. Especially socio-economic information and monetary transfer functions required for a damage risk analysis show a high uncertainty. There- fore this study helps to analyse the weak points of the flood risk and damage risk assessment procedure.

  15. Application of a trigonometric finite difference procedure to numerical analysis of compressive and shear buckling of orthotropic panels

    NASA Technical Reports Server (NTRS)

    Stein, M.; Housner, J. D.

    1978-01-01

    A numerical analysis developed for the buckling of rectangular orthotropic layered panels under combined shear and compression is described. This analysis uses a central finite difference procedure based on trigonometric functions instead of using the conventional finite differences which are based on polynomial functions. Inasmuch as the buckle mode shape is usually trigonometric in nature, the analysis using trigonometric finite differences can be made to exhibit a much faster convergence rate than that using conventional differences. Also, the trigonometric finite difference procedure leads to difference equations having the same form as conventional finite differences; thereby allowing available conventional finite difference formulations to be converted readily to trigonometric form. For two-dimensional problems, the procedure introduces two numerical parameters into the analysis. Engineering approaches for the selection of these parameters are presented and the analysis procedure is demonstrated by application to several isotropic and orthotropic panel buckling problems. Among these problems is the shear buckling of stiffened isotropic and filamentary composite panels in which the stiffener is broken. Results indicate that a break may degrade the effect of the stiffener to the extent that the panel will not carry much more load than if the stiffener were absent.

  16. High-dose-rate Intracavitary Radiotherapy in the Management of Cervical Intraepithelial Neoplasia 3 and Carcinoma In Situ Presenting With Poor Histologic Factors After Undergoing Excisional Procedures

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

    Kim, Yong Bae, E-mail: ybkim3@yuhs.ac; Kim, Young Tae; Cho, Nam Hoon

    2012-09-01

    Purpose: To assess the effectiveness of high-dose-rate intracavitary radiotherapy (HDR-ICR) in patients with cervical intraepithelial neoplasia 3 (CIN 3) and carcinoma in situ (CIS) presenting with poor histologic factors for predicting residual disease after undergoing diagnostic excisional procedures. Methods and Materials: This study was a retrospective analysis of 166 patients with CIN 3 (n=15) and CIS (n=151) between October 1986 and December 2005. They were diagnosed by conization (n=158) and punch biopsy (n=8). Pathologic analysis showed 135 cases of endocervical gland involvement (81.4%), 74 cases of positive resection margins (44.5%), and 52 cases of malignant cells on endocervical curettage (31.3%).more » All patients were treated with HDR-ICR using Co{sup 60} or Ir{sup 192} at a cancer center. The dose was prescribed at point A located 2 cm superior to the external os and 2 cm lateral to the axis of the tandem for intact uterus. Results: Median age was 61 years (range, 29-77). The median total dose of HDR-ICR was 30 Gy/6 fractions (range, 30-52). At follow-up (median, 152 months), 2 patients developed recurrent diseases: 1 CIN 2 and 1 invasive carcinoma. One hundred and forty patients survived and 26 patients died, owing to nonmalignant intercurrent disease. Rectal bleeding occurred in one patient; however, this symptom subsided with conservative management. Conclusions: Our data showed HDR-ICR is an effective modality for CIN 3 and CIS patients presenting with poor histologic factors after excisional procedures. HDR-ICR should be considered as a definitive treatment in CIN 3 and CIS patients with possible residual disease after undergoing excisional procedures.« less

  17. Substructure procedure for including tile flexibility in stress analysis of shuttle thermal protection system

    NASA Technical Reports Server (NTRS)

    Giles, G. L.

    1980-01-01

    A substructure procedure to include the flexibility of the tile in the stress analysis of the shuttle thermal protection system (TPS) is described. In this procedure, the TPS is divided into substructures of (1) the tile which is modeled by linear finite elements and (2) the SIP which is modeled as a nonlinear continuum. This procedure was applied for loading cases of uniform pressure, uniform moment, and an aerodynamic shock on various tile thicknesses. The ratios of through-the-thickness stresses in the SIP which were calculated using a flexible tile compared to using a rigid tile were found to be less than 1.05 for the cases considered.

  18. Evaluation of Factors Influencing Accuracy of Principal Procedure Coding Based on ICD-9-CM: An Iranian Study

    PubMed Central

    Farzandipour, Mehrdad; Sheikhtaheri, Abbas

    2009-01-01

    To evaluate the accuracy of procedural coding and the factors that influence it, 246 records were randomly selected from four teaching hospitals in Kashan, Iran. “Recodes” were assigned blindly and then compared to the original codes. Furthermore, the coders' professional behaviors were carefully observed during the coding process. Coding errors were classified as major or minor. The relations between coding accuracy and possible effective factors were analyzed by χ2 or Fisher exact tests as well as the odds ratio (OR) and the 95 percent confidence interval for the OR. The results showed that using a tabular index for rechecking codes reduces errors (83 percent vs. 72 percent accuracy). Further, more thorough documentation by the clinician positively affected coding accuracy, though this relation was not significant. Readability of records decreased errors overall (p = .003), including major ones (p = .012). Moreover, records with no abbreviations had fewer major errors (p = .021). In conclusion, not using abbreviations, ensuring more readable documentation, and paying more attention to available information increased coding accuracy and the quality of procedure databases. PMID:19471647

  19. Accuracy of the Parallel Analysis Procedure with Polychoric Correlations

    ERIC Educational Resources Information Center

    Cho, Sun-Joo; Li, Feiming; Bandalos, Deborah

    2009-01-01

    The purpose of this study was to investigate the application of the parallel analysis (PA) method for choosing the number of factors in component analysis for situations in which data are dichotomous or ordinal. Although polychoric correlations are sometimes used as input for component analyses, the random data matrices generated for use in PA…

  20. From Laser Scanning to Finite Element Analysis of Complex Buildings by Using a Semi-Automatic Procedure

    PubMed Central

    Castellazzi, Giovanni; D’Altri, Antonio Maria; Bitelli, Gabriele; Selvaggi, Ilenia; Lambertini, Alessandro

    2015-01-01

    In this paper, a new semi-automatic procedure to transform three-dimensional point clouds of complex objects to three-dimensional finite element models is presented and validated. The procedure conceives of the point cloud as a stacking of point sections. The complexity of the clouds is arbitrary, since the procedure is designed for terrestrial laser scanner surveys applied to buildings with irregular geometry, such as historical buildings. The procedure aims at solving the problems connected to the generation of finite element models of these complex structures by constructing a fine discretized geometry with a reduced amount of time and ready to be used with structural analysis. If the starting clouds represent the inner and outer surfaces of the structure, the resulting finite element model will accurately capture the whole three-dimensional structure, producing a complex solid made by voxel elements. A comparison analysis with a CAD-based model is carried out on a historical building damaged by a seismic event. The results indicate that the proposed procedure is effective and obtains comparable models in a shorter time, with an increased level of automation. PMID:26225978

  1. Procedure for implementation of temperature-dependent mechanical property capability in the Engineering Analysis Language (EAL) system

    NASA Technical Reports Server (NTRS)

    Glass, David E.; Robinson, James C.

    1990-01-01

    A procedure is presented to allow the use of temperature dependent mechanical properties in the Engineering Analysis Language (EAL) System for solid structural elements. This is accomplished by including a modular runstream in the main EAL runstream. The procedure is applicable for models with multiple materials and with anisotropic properties, and can easily be incorporated into an existing EAL runstream. The procedure (which is applicable for EAL elastic solid elements) is described in detail, followed by a description of the validation of the routine. A listing of the EAL runstream used to validate the procedure is included in the Appendix.

  2. Function Allocation in Complex Socio-Technical Systems: Procedure usage in nuclear power and the Context Analysis Method for Identifying Design Solutions (CAMIDS) Model

    NASA Astrophysics Data System (ADS)

    Schmitt, Kara Anne

    This research aims to prove that strict adherence to procedures and rigid compliance to process in the US Nuclear Industry may not prevent incidents or increase safety. According to the Institute of Nuclear Power Operations, the nuclear power industry has seen a recent rise in events, and this research claims that a contributing factor to this rise is organizational, cultural, and based on peoples overreliance on procedures and policy. Understanding the proper balance of function allocation, automation and human decision-making is imperative to creating a nuclear power plant that is safe, efficient, and reliable. This research claims that new generations of operators are less engaged and thinking because they have been instructed to follow procedures to a fault. According to operators, they were once to know the plant and its interrelations, but organizationally more importance is now put on following procedure and policy. Literature reviews were performed, experts were questioned, and a model for context analysis was developed. The Context Analysis Method for Identifying Design Solutions (CAMIDS) Model was created, verified and validated through both peer review and application in real world scenarios in active nuclear power plant simulators. These experiments supported the claim that strict adherence and rigid compliance to procedures may not increase safety by studying the industry's propensity for following incorrect procedures, and when it directly affects the outcome of safety or security of the plant. The findings of this research indicate that the younger generations of operators rely highly on procedures, and the organizational pressures of required compliance to procedures may lead to incidents within the plant because operators feel pressured into following the rules and policy above performing the correct actions in a timely manner. The findings support computer based procedures, efficient alarm systems, and skill of the craft matrices. The solution to

  3. Accuracy of remotely sensed data: Sampling and analysis procedures

    NASA Technical Reports Server (NTRS)

    Congalton, R. G.; Oderwald, R. G.; Mead, R. A.

    1982-01-01

    A review and update of the discrete multivariate analysis techniques used for accuracy assessment is given. A listing of the computer program written to implement these techniques is given. New work on evaluating accuracy assessment using Monte Carlo simulation with different sampling schemes is given. The results of matrices from the mapping effort of the San Juan National Forest is given. A method for estimating the sample size requirements for implementing the accuracy assessment procedures is given. A proposed method for determining the reliability of change detection between two maps of the same area produced at different times is given.

  4. [Perioperative complications after total hip revision surgery and their predictive factors. A series of 181 consecutive procedures].

    PubMed

    de Thomasson, E; Guingand, O; Terracher, R; Mazel, C

    2001-09-01

    We conducted a retrospective study to assess morbidity and mortality in patients undergoing revision total hip arthroplasty (THA) procedures. Perioperative complications were recorded in 181 revision procedures (162 patients) performed between January 1995 and March 1999 (117 bipolar revisions and 64 acetabular isolated revisions). There were 86 complications (68 patients) leading to 21 new revisions. About half (50/86) were related to the surgical procedure (dislocation, femoral fracture, infection.). Life-threatening complications (3.6%) ended in patient death in 1.6% of the cases. Complications were more frequent in patients with an ASA score=3 (p<0.01) or aged over 75 years (p<0.05). Age was also predictive of femoral misalignment and fracture (p<0.05). Dislocations (8.8%) were observed more frequently in patients who had undergone more than 2 procedures prior to the revision (p<0.05) (4.8% of the dislocations in patients undergoing a first revision procedure and 14.3% in the others). In addition, peroperative blood loss and duration of the procedure were significantly greater in case of bipolar replacement than for isolated acetabular replacement (sigma > 1.96). Our experience and data in the literature point to the important age factor in the development of complications. Preservation of a well-fixed femoral component does not appear to worsen prognosis and leads to fewer complications than bipolar changes. The decision to revise a THA must take into consideration the functional impairment but also the risks inherent in revision procedures, particularly in old patients who have undergone several procedures. Revising the acetabular component alone can be an interesting option if the femoral component remains well-fixed although our follow-up is insufficient to determine whether this attitude provides better long-term outcome than complete biopolar revision. Better patient selection and improved operative technique, in particular in femur preparation, should

  5. A qualitative analysis of the determinants in the choice of a French journal reviewing procedures

    NASA Astrophysics Data System (ADS)

    Morge, Ludovic

    2015-12-01

    Between 1993 and 2010, two French journals (Aster and Didaskalia) coming from different backgrounds but belonging to the same institution used to publish papers on research in science and technology education. The merging of these journals made it necessary for them to compare the different reviewing procedures used by each. This merging occurred at a time when research is becoming increasingly international which partly determines some of the reviewing procedure choices. In order for a francophone international journal to survive, it needs to take this internationalization into account in a reasoned manner. The author of this article, as a chief editor of RDST (Recherches en Didactique des Sciences et des Technologies)—the journal resulting from the merging- taking part in this merger, analyses the social, cultural and pragmatic determinants which impacted the choices made in reviewing procedures. This paper describes how these diversity of factors leads us to drop the idea of a standard reviewing procedure which would be valid for all journals.

  6. Phylogenetic Factor Analysis.

    PubMed

    Tolkoff, Max R; Alfaro, Michael E; Baele, Guy; Lemey, Philippe; Suchard, Marc A

    2018-05-01

    Phylogenetic comparative methods explore the relationships between quantitative traits adjusting for shared evolutionary history. This adjustment often occurs through a Brownian diffusion process along the branches of the phylogeny that generates model residuals or the traits themselves. For high-dimensional traits, inferring all pair-wise correlations within the multivariate diffusion is limiting. To circumvent this problem, we propose phylogenetic factor analysis (PFA) that assumes a small unknown number of independent evolutionary factors arise along the phylogeny and these factors generate clusters of dependent traits. Set in a Bayesian framework, PFA provides measures of uncertainty on the factor number and groupings, combines both continuous and discrete traits, integrates over missing measurements and incorporates phylogenetic uncertainty with the help of molecular sequences. We develop Gibbs samplers based on dynamic programming to estimate the PFA posterior distribution, over 3-fold faster than for multivariate diffusion and a further order-of-magnitude more efficiently in the presence of latent traits. We further propose a novel marginal likelihood estimator for previously impractical models with discrete data and find that PFA also provides a better fit than multivariate diffusion in evolutionary questions in columbine flower development, placental reproduction transitions and triggerfish fin morphometry.

  7. Optimized Standard Operating Procedures for the Analysis of Cerebrospinal Fluid Aβ42 and the Ratios of Aβ Isoforms Using Low Protein Binding Tubes.

    PubMed

    Vanderstichele, Hugo Marcel Johan; Janelidze, Shorena; Demeyer, Leentje; Coart, Els; Stoops, Erik; Herbst, Victor; Mauroo, Kimberley; Brix, Britta; Hansson, Oskar

    2016-05-31

    Reduced cerebrospinal fluid (CSF) concentration of amyloid-β1-42 (Aβ1-42) reflects the presence of amyloidopathy in brains of subjects with Alzheimer's disease (AD). To qualify the use of Aβ1-42/Aβ1-40 for improvement of standard operating procedures (SOP) for measurement of CSF Aβ with a focus on CSF collection, storage, and analysis. Euroimmun ELISAs for CSF Aβ isoforms were used to set up a SOP with respect to recipient properties (low binding, polypropylene), volume of tubes, freeze/thaw cycles, addition of detergents (Triton X-100, Tween-20) in collection or storage tubes or during CSF analysis. Data were analyzed with linear repeated measures and mixed effects models. Optimization of CSF analysis included a pre-wash of recipients (e.g., tubes, 96-well plates) before sample analysis. Using the Aβ1-42/Aβ1-40 ratio, in contrast to Aβ1-42, eliminated effects of tube type, additional freeze/thaw cycles, or effect of CSF volumes for polypropylene storage tubes. 'Low binding' tubes reduced the loss of Aβ when aliquoting CSF or in function of additional freeze/thaw cycles. Addition of detergent in CSF collection tubes resulted in an almost complete absence of variation in function of collection procedures, but affected the concentration of Aβ isoforms in the immunoassay. The ratio of Aβ1-42/Aβ1-40 is a more robust biomarker than Aβ1-42 toward (pre-) analytical interfering factors. Further, 'low binding' recipients and addition of detergent in collection tubes are able to remove effects of SOP-related confounding factors. Integration of the Aβ1-42/Aβ1-40 ratio and 'low-binding tubes' into guidance criteria may speed up worldwide standardization of CSF biomarker analysis.

  8. The Big-Five factor structure as an integrative framework: an analysis of Clarke's AVA model.

    PubMed

    Goldberg, L R; Sweeney, D; Merenda, P F; Hughes, J E

    1996-06-01

    Using a large (N = 3,629) sample of participants selected to be representative of U.S. working adults in the year 2,000, we provide links between the constructs in 2 personality models that have been derived from quite different rationales. We demonstrate the use of a novel procedure for providing orthogonal Big-Five factor scores and use those scores to analyze the scales of the Activity Vector Analysis (AVA). We discuss the implications of our many findings both for the science of personality assessment and for future research using the AVA model.

  9. 48 CFR 45.202 - Evaluation procedures.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Evaluation procedures. 45... MANAGEMENT GOVERNMENT PROPERTY Solicitation and Evaluation Procedures 45.202 Evaluation procedures. (a) The... evaluation purposes only, a rental equivalent evaluation factor. (b) The contracting officer shall ensure the...

  10. Human factors evaluation of teletherapy: Function and task analysis. Volume 2

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

    Kaye, R.D.; Henriksen, K.; Jones, R.

    1995-07-01

    As a treatment methodology, teletherapy selectively destroys cancerous and other tissue by exposure to an external beam of ionizing radiation. Sources of radiation are either a radioactive isotope, typically Cobalt-60 (Co-60), or a linear accelerator. Records maintained by the NRC have identified instances of teletherapy misadministration where the delivered radiation dose has differed from the radiation prescription (e.g., instances where fractions were delivered to the wrong patient, to the wrong body part, or were too great or too little with respect to the defined treatment volume). Both human error and machine malfunction have led to misadministrations. Effective and safe treatmentmore » requires a concern for precision and consistency of human-human and human-machine interactions throughout the course of therapy. The present study is the first part of a series of human factors evaluations for identifying the root causes that lead to human error in the teletherapy environment. The human factors evaluations included: (1) a function and task analysis of teletherapy activities, (2) an evaluation of the human-system interfaces, (3) an evaluation of procedures used by teletherapy staff, (4) an evaluation of the training and qualifications of treatment staff (excluding the oncologists), (5) an evaluation of organizational practices and policies, and (6) an identification of problems and alternative approaches for NRC and industry attention. The present report addresses the function and task analysis of teletherapy activities and provides the foundation for the conduct of the subsequent evaluations. The report includes sections on background, methodology, a description of the function and task analysis, and use of the task analysis findings for the subsequent tasks. The function and task analysis data base also is included.« less

  11. A risk-factor analysis of medical litigation judgments related to fall injuries in Korea.

    PubMed

    Kim, Insook; Won, Seonae; Lee, Mijin; Lee, Won

    2018-01-01

    The aim of this study was to find out the risk factors through analysis of seven medical malpractice judgments related to fall injuries. The risk factors were analysed by using the framework that approaches falls from a systems perspective and comprised people, organisational or environmental factors, with each factor being comprised of subfactors. The risk factors found in each of the seven judgments were aggregated into one framework. The risk factors related to patients (i.e. the people factor) were age, pain, related disease, activities and functional status, urination state, cognitive function impairment, past history of fall, blood transfusion, sleep endoscopy state and uncooperative attitude. The risk factors related to the medical staff and caregivers (i.e. people factor) were observation negligence, no fall prevention activities and negligence in managing high-risk group for fall. Organisational risk factors were a lack of workforce, a lack of training, neglecting the management of the high-risk group, neglecting the management of caregivers and the absence of a fall prevention procedure. Regarding the environment, the risk factors were found to be the emergency room, chairs without a backrest and the examination table. Identifying risk factors is essential for preventing fall accidents, since falls are preventable patient-safety incidents. Falls do not happen as a result of a single risk factor. Therefore, a systems approach is effective to identify risk factors, especially organisational and environmental factors.

  12. A Procedure for Modeling Structural Component/Attachment Failure Using Transient Finite Element Analysis

    NASA Technical Reports Server (NTRS)

    Lovejoy, Andrew E.; Jegley, Dawn C. (Technical Monitor)

    2007-01-01

    Structures often comprise smaller substructures that are connected to each other or attached to the ground by a set of finite connections. Under static loading one or more of these connections may exceed allowable limits and be deemed to fail. Of particular interest is the structural response when a connection is severed (failed) while the structure is under static load. A transient failure analysis procedure was developed by which it is possible to examine the dynamic effects that result from introducing a discrete failure while a structure is under static load. The failure is introduced by replacing a connection load history by a time-dependent load set that removes the connection load at the time of failure. The subsequent transient response is examined to determine the importance of the dynamic effects by comparing the structural response with the appropriate allowables. Additionally, this procedure utilizes a standard finite element transient analysis that is readily available in most commercial software, permitting the study of dynamic failures without the need to purchase software specifically for this purpose. The procedure is developed and explained, demonstrated on a simple cantilever box example, and finally demonstrated on a real-world example, the American Airlines Flight 587 (AA587) vertical tail plane (VTP).

  13. A single factor underlies the metabolic syndrome: a confirmatory factor analysis.

    PubMed

    Pladevall, Manel; Singal, Bonita; Williams, L Keoki; Brotons, Carlos; Guyer, Heidi; Sadurni, Josep; Falces, Carles; Serrano-Rios, Manuel; Gabriel, Rafael; Shaw, Jonathan E; Zimmet, Paul Z; Haffner, Steven

    2006-01-01

    Confirmatory factor analysis (CFA) was used to test the hypothesis that the components of the metabolic syndrome are manifestations of a single common factor. Three different datasets were used to test and validate the model. The Spanish and Mauritian studies included 207 men and 203 women and 1,411 men and 1,650 women, respectively. A third analytical dataset including 847 men was obtained from a previously published CFA of a U.S. population. The one-factor model included the metabolic syndrome core components (central obesity, insulin resistance, blood pressure, and lipid measurements). We also tested an expanded one-factor model that included uric acid and leptin levels. Finally, we used CFA to compare the goodness of fit of one-factor models with the fit of two previously published four-factor models. The simplest one-factor model showed the best goodness-of-fit indexes (comparative fit index 1, root mean-square error of approximation 0.00). Comparisons of one-factor with four-factor models in the three datasets favored the one-factor model structure. The selection of variables to represent the different metabolic syndrome components and model specification explained why previous exploratory and confirmatory factor analysis, respectively, failed to identify a single factor for the metabolic syndrome. These analyses support the current clinical definition of the metabolic syndrome, as well as the existence of a single factor that links all of the core components.

  14. Concomitant apical suspensory procedures in women with anterior vaginal wall prolapse in the United States in 2011.

    PubMed

    Northington, Gina M; Hudson, Catherine O; Karp, Deborah R; Huber, Sarah A

    2016-04-01

    Although the surgical restoration of apical support has been shown to decrease reoperation rates, it is unclear whether this has been incorporated into current practice. The aims of this study were to determine the rate of concomitant apical suspensory procedures in women with anterior vaginal wall prolapse undergoing surgical repair in 2011 and to identify associated factors. This cross-sectional study queried the Nationwide Inpatient Sample for women with a primary diagnosis of cystocele who underwent prolapse repair in 2011. The study cohort was analyzed for demographics, concomitant procedures, and hospital characteristics. The rate of apical suspensory procedures was determined. Factors potentially associated with receiving concomitant apical suspensory procedure were evaluated using univariate analysis and multivariate logistic regression. A total of 2,900 women in the database had a primary diagnosis of cystocele and underwent surgical prolapse repair in 2011. 925 (31.9 %) subjects underwent a concomitant apical suspensory procedure. The mean age in the study cohort was 61.9 ± 12.8 years. Hysterectomies were performed in 11.1 % of subjects. 61.1 % were performed vaginally, 26.5 % laparoscopically, and 12.5 % abdominally. On multivariate analysis, age greater than 50 years, Caucasian race, concomitant hysterectomy, and an urban teaching hospital setting were independently associated with receiving concomitant apical suspensory procedure in 2011. Despite evidence that the restoration of apical support is important for optimal anterior support, the overall rate of concomitant apical suspensory procedures is low. Several factors may play a role in whether or not women receive an apical suspensory procedure. This study highlights opportunities to improve the quality of surgical care provided to women with anterior vaginal prolapse.

  15. Dosimetric factors for diagnostic nuclear medicine procedures in a non-reference pregnant phantom.

    PubMed

    Rafat-Motavalli, Laleh; Miri Hakimabad, Hashem; Hoseinian Azghadi, Elie

    2018-05-01

    This study was evaluated the impact of using non-reference fetal models on the fetal radiation dose from diagnostic radionuclide administration. The 6 month pregnant phantoms including fetal models at 10th and 90th growth percentiles were constructed at either end of the normal range around the 50th percentile and implemented in the Monte Carlo N-Particle code version MCNPX 2.6. The code have been used then to evaluate the 99mTc S factors of interested target organs as the most common used radionuclide in nuclear medicine procedures. Substantial variations were observed in the S factors between the 10th/90th percentile phantoms from the 50th percentile phantom, with the greatest difference being 38.6 %. When the source organs were in close proximity to, or inside the fetal body, the 99mTc S factors presented strong statistical correlations with fetal body habitus. The trends observed in the S factors and the differences between various percentiles were justified by the source organs' masses, and chord length distributions (CLDs). The results of this study showed that fetal body habitus had a considerable effect on fetal dose (on average up to 8.4%) if constant fetal biokinetic data was considered for all fetal weight percentiles. However, an almost smaller variation on fetal dose (up to 5.3%) was obtained if the available biokinetic data for the reference fetus was scaled by fetal mass. © 2018 IOP Publishing Ltd.

  16. An economic analysis of adherence engineering to improve use of best practices during central line maintenance procedures.

    PubMed

    Nelson, Richard E; Angelovic, Aaron W; Nelson, Scott D; Gleed, Jeremy R; Drews, Frank A

    2015-05-01

    Adherence engineering applies human factors principles to examine non-adherence within a specific task and to guide the development of materials or equipment to increase protocol adherence and reduce human error. Central line maintenance (CLM) for intensive care unit (ICU) patients is a task through which error or non-adherence to protocols can cause central line-associated bloodstream infections (CLABSIs). We conducted an economic analysis of an adherence engineering CLM kit designed to improve the CLM task and reduce the risk of CLABSI. We constructed a Markov model to compare the cost-effectiveness of the CLM kit, which contains each of the 27 items necessary for performing the CLM procedure, compared with the standard care procedure for CLM, in which each item for dressing maintenance is gathered separately. We estimated the model using the cost of CLABSI overall ($45,685) as well as the excess LOS (6.9 excess ICU days, 3.5 excess general ward days). Assuming the CLM kit reduces the risk of CLABSI by 100% and 50%, this strategy was less costly (cost savings between $306 and $860) and more effective (between 0.05 and 0.13 more quality-adjusted life-years) compared with not using the pre-packaged kit. We identified threshold values for the effectiveness of the kit in reducing CLABSI for which the kit strategy was no longer less costly. An adherence engineering-based intervention to streamline the CLM process can improve patient outcomes and lower costs. Patient safety can be improved by adopting new approaches that are based on human factors principles.

  17. High Cost of Hospitalization for Colonic Diverticular Bleeding Depended on Repeated Bleeding and Blood Transfusion: Analysis with Diagnosis Procedure Combination Data in Japan.

    PubMed

    Ito, Yoichiro; Sakata, Yasuhisa; Yoshida, Hisako; Nonaka, Sayuri; Fujii, Susumu; Tanaka, Yuichiro; Shirai, Shimpei; Takeshita, Eri; Akutagawa, Takashi; Kawakubo, Hiroharu; Yamamoto, Koji; Tsuruoka, Nanae; Shimoda, Ryo; Iwakiri, Ryuichi; Fujimoto, Kazuma

    2017-01-01

    Bleeding from a colonic diverticulum is serious in aged patients. The aim of this study was to determine the risk factors for high-cost hospitalization of colonic diverticular bleeding using the diagnosis procedure combination (DPC) data. From January 2009 to December 2015, 78 patients with colonic diverticular bleeding were identified by DPC data in Saga Medical School Hospital. All patients underwent colonic endoscopy within 3 days. The patients were divided into 2 groups: the low-cost group (DPC cost of <500,000 yen) and the high-cost group (DPC cost of >500,000 yen). Univariate analysis revealed that aging, hypertension, rebleeding, a low hemoglobin concentration at admission, and blood transfusion were risk factors for high hospitalization cost. Multivariate analysis revealed that rebleeding (OR 5.3; 95% CI 1.3-21.3; p = 0.017) and blood transfusion (OR 3.8; 95% CI 1.01-14.2; p = 0.048) were definite risk factors for high hospitalization cost. Rebleeding and blood transfusion were related to high hospitalization cost for colonic diverticular bleeding. © 2017 S. Karger AG, Basel.

  18. Anthropometric data reduction using confirmatory factor analysis.

    PubMed

    Rohani, Jafri Mohd; Olusegun, Akanbi Gabriel; Rani, Mat Rebi Abdul

    2014-01-01

    The unavailability of anthropometric data especially in developing countries has remained a limiting factor towards the design of learning facilities with sufficient ergonomic consideration. Attempts to use anthropometric data from developed countries have led to provision of school facilities unfit for the users. The purpose of this paper is to use factor analysis to investigate the suitability of the collected anthropometric data as a database for school design in Nigerian tertiary institutions. Anthropometric data were collected from 288 male students in a Federal Polytechnic in North-West of Nigeria. Their age is between 18-25 years. Nine vertical anthropometric dimensions related to heights were collected using the conventional traditional equipment. Exploratory factor analysis was used to categorize the variables into a model consisting of two factors. Thereafter, confirmatory factor analysis was used to investigate the fit of the data to the proposed model. A just identified model, made of two factors, each with three variables was developed. The variables within the model accounted for 81% of the total variation of the entire data. The model was found to demonstrate adequate validity and reliability. Various measuring indices were used to verify that the model fits the data properly. The final model reveals that stature height and eye height sitting were the most stable variables for designs that have to do with standing and sitting construct. The study has shown the application of factor analysis in anthropometric data analysis. The study highlighted the relevance of these statistical tools to investigate variability among anthropometric data involving diverse population, which has not been widely used for analyzing previous anthropometric data. The collected data is therefore suitable for use while designing for Nigerian students.

  19. Direct versus indirect revascularization procedures for moyamoya disease: a comparative effectiveness study.

    PubMed

    Macyszyn, Luke; Attiah, Mark; Ma, Tracy S; Ali, Zarina; Faught, Ryan; Hossain, Alisha; Man, Karen; Patel, Hiren; Sobota, Rosanna; Zager, Eric L; Stein, Sherman C

    2017-05-01

    OBJECTIVE Moyamoya disease (MMD) is a chronic cerebrovascular disease that can lead to devastating neurological outcomes. Surgical intervention is the definitive treatment, with direct, indirect, and combined revascularization procedures currently employed by surgeons. The optimal surgical approach, however, remains unclear. In this decision analysis, the authors compared the effectiveness of revascularization procedures in both adult and pediatric patients with MMD. METHODS A comprehensive literature search was performed for studies of MMD. Using complication and success rates from the literature, the authors constructed a decision analysis model for treatment using a direct and indirect revascularization technique. Utility values for the various outcomes and complications were extracted from the literature examining preferences in similar clinical conditions. Sensitivity analysis was performed. RESULTS A structured literature search yielded 33 studies involving 4197 cases. Cases were divided into adult and pediatric populations. These were further subdivided into 3 different treatment groups: indirect, direct, and combined revascularization procedures. In the pediatric population at 5- and 10-year follow-up, there was no significant difference between indirect and combination procedures, but both were superior to direct revascularization. In adults at 4-year follow-up, indirect was superior to direct revascularization. CONCLUSIONS In the absence of factors that dictate a specific approach, the present decision analysis suggests that direct revascularization procedures are inferior in terms of quality-adjusted life years in both adults at 4 years and children at 5 and 10 years postoperatively, respectively. These findings were statistically significant (p < 0.001 in all cases), suggesting that indirect and combination procedures may offer optimal results at long-term follow-up.

  20. RANDOMIZATION PROCEDURES FOR THE ANALYSIS OF EDUCATIONAL EXPERIMENTS.

    ERIC Educational Resources Information Center

    COLLIER, RAYMOND O.

    CERTAIN SPECIFIC ASPECTS OF HYPOTHESIS TESTS USED FOR ANALYSIS OF RESULTS IN RANDOMIZED EXPERIMENTS WERE STUDIED--(1) THE DEVELOPMENT OF THE THEORETICAL FACTOR, THAT OF PROVIDING INFORMATION ON STATISTICAL TESTS FOR CERTAIN EXPERIMENTAL DESIGNS AND (2) THE DEVELOPMENT OF THE APPLIED ELEMENT, THAT OF SUPPLYING THE EXPERIMENTER WITH MACHINERY FOR…

  1. Scenes for Social Information Processing in Adolescence: Item and factor analytic procedures for psychometric appraisal.

    PubMed

    Vagos, Paula; Rijo, Daniel; Santos, Isabel M

    2016-04-01

    Relatively little is known about measures used to investigate the validity and applications of social information processing theory. The Scenes for Social Information Processing in Adolescence includes items built using a participatory approach to evaluate the attribution of intent, emotion intensity, response evaluation, and response decision steps of social information processing. We evaluated a sample of 802 Portuguese adolescents (61.5% female; mean age = 16.44 years old) using this instrument. Item analysis and exploratory and confirmatory factor analytic procedures were used for psychometric examination. Two measures for attribution of intent were produced, including hostile and neutral; along with 3 emotion measures, focused on negative emotional states; 8 response evaluation measures; and 4 response decision measures, including prosocial and impaired social behavior. All of these measures achieved good internal consistency values and fit indicators. Boys seemed to favor and choose overt and relational aggression behaviors more often; girls conveyed higher levels of neutral attribution, sadness, and assertiveness and passiveness. The Scenes for Social Information Processing in Adolescence achieved adequate psychometric results and seems a valuable alternative for evaluating social information processing, even if it is essential to continue investigation into its internal and external validity. (c) 2016 APA, all rights reserved.

  2. A Study of Reading Errors Using Goodman's Miscue Analysis and Cloze Procedure.

    ERIC Educational Resources Information Center

    Farren, Sean N.

    A study of 11 boys, aged 12 to 14 with low reading ability, was conducted to discover what kinds of errors they made and whether or not differences might exist between error patterns in silent and oral reading. Miscue analysis was used to test oral reading while cloze procedures were used to test silent reading. Errors were categorized according…

  3. Communication Network Analysis Methods.

    ERIC Educational Resources Information Center

    Farace, Richard V.; Mabee, Timothy

    This paper reviews a variety of analytic procedures that can be applied to network data, discussing the assumptions and usefulness of each procedure when applied to the complexity of human communication. Special attention is paid to the network properties measured or implied by each procedure. Factor analysis and multidimensional scaling are among…

  4. Comparisons of Exploratory and Confirmatory Factor Analysis.

    ERIC Educational Resources Information Center

    Daniel, Larry G.

    Historically, most researchers conducting factor analysis have used exploratory methods. However, more recently, confirmatory factor analytic methods have been developed that can directly test theory either during factor rotation using "best fit" rotation methods or during factor extraction, as with the LISREL computer programs developed…

  5. Safety of Running Two Rooms: A Systematic Review and Meta-Analysis of Overlapping Neurosurgical Procedures.

    PubMed

    Self, D Mitchell; Ilyas, Adeel; Stetler, William R

    2018-04-27

    Overlapping surgery, a long-standing practice within academic neurosurgery centers nationwide, has recently come under scrutiny from the government and media as potentially harmful to patients. Therefore, the objective of this systematic review and meta-analysis is to determine the safety of overlapping neurosurgical procedures. The authors performed a systematic review and meta-analysis in accordance with PRISMA guidelines. A review of PubMed and Medline databases was undertaken with the search phrase "overlapping surgery AND neurosurgery AND outcomes." Data regarding patient demographics, type of neurosurgical procedure, and outcomes and complications were extracted from each study. The principle summary measure was odds ratio (OR) of the association of overlapping versus non-overlapping surgery with outcomes. The literature search yielded a total of 36 studies, of which 5 studies met inclusion criteria and were included in this study. These studies included a total of 25,764 patients undergoing neurosurgical procedures. Overlapping surgery was associated with an increased likelihood of being discharged home (OR = 1.32; 95% CI 1.20 to 1.44; P < 0.001) and a reduced 30-day unexpected return to the operating room (OR = 0.79; 95% CI 0.72 to 0.87; P < 0.001). Overlapping surgery did not significantly affect OR of length of surgery, 30-day mortality, or 30-day readmission. Overlapping neurosurgical procedures were not associated with worse patient outcomes. Additional, prospective studies are needed to further assess the safety overlapping procedures. Copyright © 2018. Published by Elsevier Inc.

  6. [Costing nuclear medicine diagnostic procedures].

    PubMed

    Markou, Pavlos

    2005-01-01

    To the Editor: Referring to a recent special report about the cost analysis of twenty-nine nuclear medicine procedures, I would like to clarify some basic aspects for determining costs of nuclear medicine procedure with various costing methodologies. Activity Based Costing (ABC) method, is a new approach in imaging services costing that can provide the most accurate cost data, but is difficult to perform in nuclear medicine diagnostic procedures. That is because ABC requires determining and analyzing all direct and indirect costs of each procedure, according all its activities. Traditional costing methods, like those for estimating incomes and expenses per procedure or fixed and variable costs per procedure, which are widely used in break-even point analysis and the method of ratio-of-costs-to-charges per procedure may be easily performed in nuclear medicine departments, to evaluate the variability and differences between costs and reimbursement - charges.

  7. Identifying Human Factors Issues in Aircraft Maintenance Operations

    NASA Technical Reports Server (NTRS)

    Veinott, Elizabeth S.; Kanki, Barbara G.; Shafto, Michael G. (Technical Monitor)

    1995-01-01

    Maintenance operations incidents submitted to the Aviation Safety Reporting System (ASRS) between 1986-1992 were systematically analyzed in order to identify issues relevant to human factors and crew coordination. This exploratory analysis involved 95 ASRS reports which represented a wide range of maintenance incidents. The reports were coded and analyzed according to the type of error (e.g, wrong part, procedural error, non-procedural error), contributing factors (e.g., individual, within-team, cross-team, procedure, tools), result of the error (e.g., aircraft damage or not) as well as the operational impact (e.g., aircraft flown to destination, air return, delay at gate). The main findings indicate that procedural errors were most common (48.4%) and that individual and team actions contributed to the errors in more than 50% of the cases. As for operational results, most errors were either corrected after landing at the destination (51.6%) or required the flight crew to stop enroute (29.5%). Interactions among these variables are also discussed. This analysis is a first step toward developing a taxonomy of crew coordination problems in maintenance. By understanding what variables are important and how they are interrelated, we may develop intervention strategies that are better tailored to the human factor issues involved.

  8. 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…

  9. SFCHECK: a unified set of procedures for evaluating the quality of macromolecular structure-factor data and their agreement with the atomic model.

    PubMed

    Vaguine, A A; Richelle, J; Wodak, S J

    1999-01-01

    In this paper we present SFCHECK, a stand-alone software package that features a unified set of procedures for evaluating the structure-factor data obtained from X-ray diffraction experiments and for assessing the agreement of the atomic coordinates with these data. The evaluation is performed completely automatically, and produces a concise PostScript pictorial output similar to that of PROCHECK [Laskowski, MacArthur, Moss & Thornton (1993). J. Appl. Cryst. 26, 283-291], greatly facilitating visual inspection of the results. The required inputs are the structure-factor amplitudes and the atomic coordinates. Having those, the program summarizes relevant information on the deposited structure factors and evaluates their quality using criteria such as data completeness, structure-factor uncertainty and the optical resolution computed from the Patterson origin peak. The dependence of various parameters on the nominal resolution (d spacing) is also given. To evaluate the global agreement of the atomic model with the experimental data, the program recomputes the R factor, the correlation coefficient between observed and calculated structure-factor amplitudes and Rfree (when appropriate). In addition, it gives several estimates of the average error in the atomic coordinates. The local agreement between the model and the electron-density map is evaluated on a per-residue basis, considering separately the macromolecule backbone and side-chain atoms, as well as solvent atoms and heterogroups. Among the criteria are the normalized average atomic displacement, the local density correlation coefficient and the polymer chain connectivity. The possibility of computing these criteria using the omit-map procedure is also provided. The described software should be a valuable tool in monitoring the refinement procedure and in assessing structures deposited in databases.

  10. Analysis of Academic Administrators' Attitudes: Annual Evaluations and Factors That Improve Teaching

    ERIC Educational Resources Information Center

    Cherry, Brian D.; Grasse, Nathan; Kapla, Dale; Hamel, Brad

    2017-01-01

    This article examines academic administrators' attitudes towards the academic evaluation process in the US and those factors that are utilised to improve teaching. We use path regressions to examine satisfaction with evaluation procedures, as well as the direct and indirect effects of these factors on perceptions of whether the evaluation process…

  11. Power analysis for multivariate and repeated measures designs: a flexible approach using the SPSS MANOVA procedure.

    PubMed

    D'Amico, E J; Neilands, T B; Zambarano, R

    2001-11-01

    Although power analysis is an important component in the planning and implementation of research designs, it is often ignored. Computer programs for performing power analysis are available, but most have limitations, particularly for complex multivariate designs. An SPSS procedure is presented that can be used for calculating power for univariate, multivariate, and repeated measures models with and without time-varying and time-constant covariates. Three examples provide a framework for calculating power via this method: an ANCOVA, a MANOVA, and a repeated measures ANOVA with two or more groups. The benefits and limitations of this procedure are discussed.

  12. Conditional Versus Unconditional Procedures for Sample-Free Item Analysis

    ERIC Educational Resources Information Center

    Wright, Benjamin D.; Douglas, Graham A.

    1977-01-01

    Two procedures for Rasch, sample-free item calibration are reviewed and compared for accuracy. The theoretically ideal "conditional" procedure is impractical for more than fifteen items. The more practical but biased "unconditional" procedure is discussed in detail. (Author/JKS)

  13. On the Extraction of Components and the Applicability of the Factor Model.

    ERIC Educational Resources Information Center

    Dziuban, Charles D.; Harris, Chester W.

    A reanalysis of Shaycroft's matrix of intercorrelations of 10 test variables plus 4 random variables is discussed. Three different procedures were used in the reanalysis: (1) Image Component Analysis, (2) Uniqueness Rescaling Factor Analysis, and (3) Alpha Factor Analysis. The results of these analyses are presented in tables. It is concluded from…

  14. 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…

  15. Nurses' discourse in contraceptive prescribing: an analysis using Foucault's 'procedures of exclusion'.

    PubMed

    Hayter, Mark

    2007-05-01

    This paper is a report of an analysis of the discourse about contraceptive efficacy and side effects used by nurses when prescribing contraception. All women seeking contraception should be informed of the efficacy and potential adverse effects of the particular method they are considering. This information facilitates an informed choice. Women also require this information in order to monitor for any side effects. Paradoxically, side effects are also a key factor in reducing adherence with contraceptive regimens. However, there is no literature that explores specifically how this issue is addressed in clinical consultations, or places these practices in a theoretical context. Forty-nine consultations between nurses and women in sexual health clinics were audio-recorded during 2002. Data were subject to a discourse analysis using Foucault's 'procedures of exclusion' to explore the discursive construction of contraceptive efficacy and side effects The nurses employed specific discursive strategies when discussing contraception. When addressing efficacy, discourse centred on medico-statistical facts, but side effects were described in lay terms that minimized their severity. Nurses contextualized contraceptive side effects within potential problems that women might experience in pregnancy, and also attempted to 'normalize' contraceptive-related problems. Discourse and its deployment play a key role in practitioner-client relationships that sexual health nurses need to become more aware of how they discuss clinical issues about contraception with women. Clinical data on contraceptive side-effects are present in the literature, and it is important that sexual health nurses use this to help women make truly informed decisions.

  16. A combined qualitative and quantitative procedure for the chemical analysis of urinary calculi

    PubMed Central

    Hodgkinson, A.

    1971-01-01

    A better understanding of the physico-chemical principles underlying the formation of calculus has led to a need for more precise information on the chemical composition of stones. A combined qualitative and quantitative procedure for the chemical analysis of urinary calculi which is suitable for routine use is presented. The procedure involves five simple qualitative tests followed by the quantitative determination of calcium, magnesium, inorganic phosphate, and oxalate. These data are used to calculate the composition of the stone in terms of calcium oxalate, apatite, and magnesium ammonium phosphate. Analytical results and derived values for five representative types of calculi are presented. PMID:5551382

  17. Predicting the difficulty of a lead extraction procedure: the LED index.

    PubMed

    Bontempi, Luca; Vassanelli, Francesca; Cerini, Manuel; D'Aloia, Antonio; Vizzardi, Enrico; Gargaro, Alessio; Chiusso, Francesco; Mamedouv, Rashad; Lipari, Alessandro; Curnis, Antonio

    2014-08-01

    According to recent surveys, many sites performing permanent lead extractions do not meet the minimum prerequisites concerning personnel training, procedures' volume, or facility requirements. The current Heart Rhythm Society consensus on lead extractions suggests that patients should be referred to more experienced sites when a better outcome could be achieved. The purpose of this study was to develop a score aimed at predicting the difficulty of a lead extraction procedure through the analysis of a high-volume center database. This score could help to discriminate patients who should be sent to a referral site. A total of 889 permanent leads were extracted from 469 patients. All procedures were performed from January 2009 to May 2012 by two expert electrophysiologists, at the University Hospital of Brescia. Factors influencing the difficulty of a procedure were assessed using a univariate and a multivariate logistic regression model. The fluoroscopy time of the procedure was taken as an index of difficulty. A Lead Extraction Difficulty (LED) score was defined, considering the strongest predictors. Overall, 873 of 889 (98.2%) leads were completely removed. Major complications were reported in one patient (0.2%) who manifested cardiac tamponade. Minor complications occurred in six (1.3%) patients. No deaths occurred. Median fluoroscopic time was 8.7 min (3.3-17.3). A procedure was classified as difficult when fluoroscopy time was more than 31.2 min [90th percentile (PCTL)].At a univariate analysis, the number of extracted leads and years from implant were significantly associated with an increased risk of fluoroscopy time above 90th PCTL [odds ratio (OR) 1.51, 95% confidence interval (CI) 1.08-2.11, P = 0.01; and OR 1.19, 95% CI 1.12-1.25, P < 0.001, respectively). After adjusting for patient age and sex, and combining with other covariates potentially influencing the extraction procedure, a multivariate analysis confirmed a 71% increased risk of fluoroscopy time

  18. Multiple Interacting Risk Factors: On Methods for Allocating Risk Factor Interactions.

    PubMed

    Price, Bertram; MacNicoll, Michael

    2015-05-01

    A persistent problem in health risk analysis where it is known that a disease may occur as a consequence of multiple risk factors with interactions is allocating the total risk of the disease among the individual risk factors. This problem, referred to here as risk apportionment, arises in various venues, including: (i) public health management, (ii) government programs for compensating injured individuals, and (iii) litigation. Two methods have been described in the risk analysis and epidemiology literature for allocating total risk among individual risk factors. One method uses weights to allocate interactions among the individual risk factors. The other method is based on risk accounting axioms and finding an optimal and unique allocation that satisfies the axioms using a procedure borrowed from game theory. Where relative risk or attributable risk is the risk measure, we find that the game-theory-determined allocation is the same as the allocation where risk factor interactions are apportioned to individual risk factors using equal weights. Therefore, the apportionment problem becomes one of selecting a meaningful set of weights for allocating interactions among the individual risk factors. Equal weights and weights proportional to the risks of the individual risk factors are discussed. © 2015 Society for Risk Analysis.

  19. Random analysis of bearing capacity of square footing using the LAS procedure

    NASA Astrophysics Data System (ADS)

    Kawa, Marek; Puła, Wojciech; Suska, Michał

    2016-09-01

    In the present paper, a three-dimensional problem of bearing capacity of square footing on random soil medium is analyzed. The random fields of strength parameters c and φ are generated using LAS procedure (Local Average Subdivision, Fenton and Vanmarcke 1990). The procedure used is re-implemented by the authors in Mathematica environment in order to combine it with commercial program. Since the procedure is still tested the random filed has been assumed as one-dimensional: the strength properties of soil are random in vertical direction only. Individual realizations of bearing capacity boundary-problem with strength parameters of medium defined the above procedure are solved using FLAC3D Software. The analysis is performed for two qualitatively different cases, namely for the purely cohesive and cohesive-frictional soils. For the latter case the friction angle and cohesion have been assumed as independent random variables. For these two cases the random square footing bearing capacity results have been obtained for the range of fluctuation scales from 0.5 m to 10 m. Each time 1000 Monte Carlo realizations have been performed. The obtained results allow not only the mean and variance but also the probability density function to be estimated. An example of application of this function for reliability calculation has been presented in the final part of the paper.

  20. Meta-analysis of the technical performance of an imaging procedure: guidelines and statistical methodology.

    PubMed

    Huang, Erich P; Wang, Xiao-Feng; Choudhury, Kingshuk Roy; McShane, Lisa M; Gönen, Mithat; Ye, Jingjing; Buckler, Andrew J; Kinahan, Paul E; Reeves, Anthony P; Jackson, Edward F; Guimaraes, Alexander R; Zahlmann, Gudrun

    2015-02-01

    Medical imaging serves many roles in patient care and the drug approval process, including assessing treatment response and guiding treatment decisions. These roles often involve a quantitative imaging biomarker, an objectively measured characteristic of the underlying anatomic structure or biochemical process derived from medical images. Before a quantitative imaging biomarker is accepted for use in such roles, the imaging procedure to acquire it must undergo evaluation of its technical performance, which entails assessment of performance metrics such as repeatability and reproducibility of the quantitative imaging biomarker. Ideally, this evaluation will involve quantitative summaries of results from multiple studies to overcome limitations due to the typically small sample sizes of technical performance studies and/or to include a broader range of clinical settings and patient populations. This paper is a review of meta-analysis procedures for such an evaluation, including identification of suitable studies, statistical methodology to evaluate and summarize the performance metrics, and complete and transparent reporting of the results. This review addresses challenges typical of meta-analyses of technical performance, particularly small study sizes, which often causes violations of assumptions underlying standard meta-analysis techniques. Alternative approaches to address these difficulties are also presented; simulation studies indicate that they outperform standard techniques when some studies are small. The meta-analysis procedures presented are also applied to actual [18F]-fluorodeoxyglucose positron emission tomography (FDG-PET) test-retest repeatability data for illustrative purposes. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

  1. Meta-analysis of the technical performance of an imaging procedure: Guidelines and statistical methodology

    PubMed Central

    Huang, Erich P; Wang, Xiao-Feng; Choudhury, Kingshuk Roy; McShane, Lisa M; Gönen, Mithat; Ye, Jingjing; Buckler, Andrew J; Kinahan, Paul E; Reeves, Anthony P; Jackson, Edward F; Guimaraes, Alexander R; Zahlmann, Gudrun

    2017-01-01

    Medical imaging serves many roles in patient care and the drug approval process, including assessing treatment response and guiding treatment decisions. These roles often involve a quantitative imaging biomarker, an objectively measured characteristic of the underlying anatomic structure or biochemical process derived from medical images. Before a quantitative imaging biomarker is accepted for use in such roles, the imaging procedure to acquire it must undergo evaluation of its technical performance, which entails assessment of performance metrics such as repeatability and reproducibility of the quantitative imaging biomarker. Ideally, this evaluation will involve quantitative summaries of results from multiple studies to overcome limitations due to the typically small sample sizes of technical performance studies and/or to include a broader range of clinical settings and patient populations. This paper is a review of meta-analysis procedures for such an evaluation, including identification of suitable studies, statistical methodology to evaluate and summarize the performance metrics, and complete and transparent reporting of the results. This review addresses challenges typical of meta-analyses of technical performance, particularly small study sizes, which often causes violations of assumptions underlying standard meta-analysis techniques. Alternative approaches to address these difficulties are also presented; simulation studies indicate that they outperform standard techniques when some studies are small. The meta-analysis procedures presented are also applied to actual [18F]-fluorodeoxyglucose positron emission tomography (FDG-PET) test–retest repeatability data for illustrative purposes. PMID:24872353

  2. Analysis of nasopharyngeal carcinoma risk factors with Bayesian networks.

    PubMed

    Aussem, Alex; de Morais, Sérgio Rodrigues; Corbex, Marilys

    2012-01-01

    We propose a new graphical framework for extracting the relevant dietary, social and environmental risk factors that are associated with an increased risk of nasopharyngeal carcinoma (NPC) on a case-control epidemiologic study that consists of 1289 subjects and 150 risk factors. This framework builds on the use of Bayesian networks (BNs) for representing statistical dependencies between the random variables. We discuss a novel constraint-based procedure, called Hybrid Parents and Children (HPC), that builds recursively a local graph that includes all the relevant features statistically associated to the NPC, without having to find the whole BN first. The local graph is afterwards directed by the domain expert according to his knowledge. It provides a statistical profile of the recruited population, and meanwhile helps identify the risk factors associated to NPC. Extensive experiments on synthetic data sampled from known BNs show that the HPC outperforms state-of-the-art algorithms that appeared in the recent literature. From a biological perspective, the present study confirms that chemical products, pesticides and domestic fume intake from incomplete combustion of coal and wood are significantly associated with NPC risk. These results suggest that industrial workers are often exposed to noxious chemicals and poisonous substances that are used in the course of manufacturing. This study also supports previous findings that the consumption of a number of preserved food items, like house made proteins and sheep fat, are a major risk factor for NPC. BNs are valuable data mining tools for the analysis of epidemiologic data. They can explicitly combine both expert knowledge from the field and information inferred from the data. These techniques therefore merit consideration as valuable alternatives to traditional multivariate regression techniques in epidemiologic studies. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. Analysis of Pre-Analytic Factors Affecting the Success of Clinical Next-Generation Sequencing of Solid Organ Malignancies.

    PubMed

    Chen, Hui; Luthra, Rajyalakshmi; Goswami, Rashmi S; Singh, Rajesh R; Roy-Chowdhuri, Sinchita

    2015-08-28

    Application of next-generation sequencing (NGS) technology to routine clinical practice has enabled characterization of personalized cancer genomes to identify patients likely to have a response to targeted therapy. The proper selection of tumor sample for downstream NGS based mutational analysis is critical to generate accurate results and to guide therapeutic intervention. However, multiple pre-analytic factors come into play in determining the success of NGS testing. In this review, we discuss pre-analytic requirements for AmpliSeq PCR-based sequencing using Ion Torrent Personal Genome Machine (PGM) (Life Technologies), a NGS sequencing platform that is often used by clinical laboratories for sequencing solid tumors because of its low input DNA requirement from formalin fixed and paraffin embedded tissue. The success of NGS mutational analysis is affected not only by the input DNA quantity but also by several other factors, including the specimen type, the DNA quality, and the tumor cellularity. Here, we review tissue requirements for solid tumor NGS based mutational analysis, including procedure types, tissue types, tumor volume and fraction, decalcification, and treatment effects.

  4. Round-off errors in cutting plane algorithms based on the revised simplex procedure

    NASA Technical Reports Server (NTRS)

    Moore, J. E.

    1973-01-01

    This report statistically analyzes computational round-off errors associated with the cutting plane approach to solving linear integer programming problems. Cutting plane methods require that the inverse of a sequence of matrices be computed. The problem basically reduces to one of minimizing round-off errors in the sequence of inverses. Two procedures for minimizing this problem are presented, and their influence on error accumulation is statistically analyzed. One procedure employs a very small tolerance factor to round computed values to zero. The other procedure is a numerical analysis technique for reinverting or improving the approximate inverse of a matrix. The results indicated that round-off accumulation can be effectively minimized by employing a tolerance factor which reflects the number of significant digits carried for each calculation and by applying the reinversion procedure once to each computed inverse. If 18 significant digits plus an exponent are carried for each variable during computations, then a tolerance value of 0.1 x 10 to the minus 12th power is reasonable.

  5. Comprehensive evaluation of liver resection procedures: surgical mind development through cognitive task analysis.

    PubMed

    Ho, Cheng-Maw; Wakabayashi, Go; Yeh, Chi-Chuan; Hu, Rey-Heng; Sakaguchi, Takanori; Hasegawa, Yasushi; Takahara, Takeshi; Nitta, Hiroyuki; Sasaki, Akira; Lee, Po-Huang

    2018-01-01

    Liver resection is a complex procedure for trainee surgeons. Cognitive task analysis (CTA) facilitates understanding and decomposing tasks that require a great proportion of mental activity from experts. Using CTA and video-based coaching to compare liver resection by open and laparoscopic approaches, we decomposed the task of liver resection into exposure (visual field building), adequate tension made at the working plane (which may change three-dimensionally during the resection process), and target processing (intervention strategy) that can bridge the gap from the basic surgical principle. The key steps of highly-specialized techniques, including hanging maneuvers and looping of extra-hepatic hepatic veins, were shown on video by open and laparoscopic approaches. Familiarization with laparoscopic anatomical orientation may help surgeons already skilled at open liver resection transit to perform laparoscopic liver resection smoothly. Facilities at hand (such as patient tolerability, advanced instruments, and trained teams of personnel) can influence surgical decision making. Application of the rationale and realizing the interplay between the surgical principles and the other paramedical factors may help surgeons in training to understand the mental abstractions of experienced surgeons, to choose the most appropriate surgical strategy effectively at will, and to minimize the gap.

  6. Improved enteral tolerance following step procedure: systematic literature review and meta-analysis.

    PubMed

    Fernandes, Melissa A; Usatin, Danielle; Allen, Isabel E; Rhee, Sue; Vu, Lan

    2016-10-01

    Surgical management of children with short bowel syndrome (SBS) changed with the introduction of the serial transverse enteroplasty procedure (STEP). We conducted a systematic review and meta-analysis using MEDLINE and SCOPUS to determine if children with SBS had improved enteral tolerance following STEP. Studies were included if information about a child's pre- and post-STEP enteral tolerance was provided. A random effects meta-analysis provided a summary estimate of the proportion of children with enteral tolerance increase following STEP. From 766 abstracts, seven case series involving 86 children were included. Mean percent tolerance of enteral nutrition improved from 35.1 to 69.5. Sixteen children had no enteral improvement following STEP. A summary estimate showed that 87 % (95 % CI 77-95 %) of children who underwent STEP had an increase in enteral tolerance. Compilation of the literature supports the belief that SBS subjects' enteral tolerance improves following STEP. Enteral nutritional tolerance is a measure of efficacy of STEP and should be presented as a primary or secondary outcome. By standardizing data collection on children undergoing STEP procedure, better determination of nutritional benefit from STEP can be ascertained.

  7. Assessment of Various Risk Factors for Success of Delayed and Immediate Loaded Dental Implants: A Retrospective Analysis.

    PubMed

    Prasant, M C; Thukral, Rishi; Kumar, Sachin; Sadrani, Sannishth M; Baxi, Harsh; Shah, Aditi

    2016-10-01

    Ever since its introduction in 1977, a minimum of few months of period is required for osseointegration to take place after dental implant surgery. With the passage of time and advancements in the fields of dental implant, this healing period is getting smaller and smaller. Immediate loading of dental implants is becoming a very popular procedure in the recent time. Hence, we retrospectively analyzed the various risk factors for the failure of delayed and immediate loaded dental implants. In the present study, retrospective analysis of all the patients was done who underwent dental implant surgeries either by immediate loading procedure or by delayed loading procedures. All the patients were divided broadly into two groups with one group containing patients in which delayed loaded dental implants were placed while other consisted of patients in whom immediate loaded dental implants were placed. All the patients in whom follow-up records were missing and who had past medical history of any systemic diseases were excluded from the present study. Evaluation of associated possible risk factors was done by classifying the predictable factors as primary and secondary factors. All the results were analyzed by Statistical Package for the Social Sciences (SPSS) software. Kaplan-Meier survival analyses and chi-square test were used for assessment of level of significance. In delayed and immediate group of dental implants, mean age of the patients was 54.2 and 54.8 years respectively. Statistically significant results were obtained while comparing the clinical parameters of the dental implants in both the groups while demographic parameters showed nonsignificant correlation. Significant higher risk of dental implant failure is associated with immediate loaded dental implants. Tobacco smoking, shorter implant size, and other risk factors play a significant role in predicting the success and failure of dental implants. Delayed loaded dental implant placement should be preferred

  8. 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…

  9. Monitoring the use and outcomes of new devices and procedures: how does coding affect what Hospital Episode Statistics contribute? Lessons from 12 emerging procedures 2006-10.

    PubMed

    Patrick, Hannah; Sims, Andrew; Burn, Julie; Bousfield, Derek; Colechin, Elaine; Reay, Christopher; Alderson, Neil; Goode, Stephen; Cunningham, David; Campbell, Bruce

    2013-03-01

    New devices and procedures are often introduced into health services when the evidence base for their efficacy and safety is limited. The authors sought to assess the availability and accuracy of routinely collected Hospital Episodes Statistics (HES) data in the UK and their potential contribution to the monitoring of new procedures. Four years of HES data (April 2006-March 2010) were analysed to identify episodes of hospital care involving a sample of 12 new interventional procedures. HES data were cross checked against other relevant sources including national or local registers and manufacturers' information. HES records were available for all 12 procedures during the entire study period. Comparative data sources were available from national (5), local (2) and manufacturer (2) registers. Factors found to affect comparisons were miscoding, alternative coding and inconsistent use of subsidiary codes. The analysis of provider coverage showed that HES is sensitive at detecting centres which carry out procedures, but specificity is poor in some cases. Routinely collected HES data have the potential to support quality improvements and evidence-based commissioning of devices and procedures in health services but achievement of this potential depends upon the accurate coding of procedures.

  10. Stapled hemorrhoidopexy, an innovative surgical procedure for hemorrhoidal prolapse: cost-utility analysis.

    PubMed

    Ribarić, Goran; Kofler, Justus; Jayne, David G

    2011-08-15

    To undertake full economic evaluation of stapled hemorrhoidopexy (PPH) to establish its cost-effectiveness and investigate whether PPH can become cost-saving compared to conventional excisional hemorrhoidectomy (CH). A cost-utility analysis in hospital and health care system (UK) was undertaken using a probabilistic, cohort-based decision tree to compare the use of PPH with CH. Sensitivity analyses allowed showing outcomes in regard to the variations in clinical practice of PPH procedure. The participants were patients undergoing initial surgical treatment of third and fourth degree hemorrhoids within a 1-year time-horizon. Data on clinical effectiveness were obtained from a systematic review of the literature. Main outcome measures were the cost per procedure at the hospital level, total direct costs from the health care system perspective, quality adjusted life years (QALY) gained and incremental cost per QALY gained. A decrease in operating theater time and hospital stay associated with PPH led to a cost saving compared to CH of GBP 27 (US $43.11, €30.50) per procedure at the hospital level and to an incremental cost of GBP 33 (US $52.68, €37.29) after one year from the societal perspective. Calculation of QALYs induced an incremental QALY of 0.0076 and showed an incremental cost-effective ratio (ICER) of GBP 4316 (US $6890.47, €4878.37). Taking into consideration recent literature on clinical outcomes, PPH becomes cost saving compared to CH for the health care system. PPH is a cost-effective procedure with an ICER of GBP 4136 and it seems that an innovative surgical procedure could be cost saving in routine clinical practice.

  11. Interdisciplinary analysis procedures in the modeling and control of large space-based structures

    NASA Technical Reports Server (NTRS)

    Cooper, Paul A.; Stockwell, Alan E.; Kim, Zeen C.

    1987-01-01

    The paper describes a computer software system called the Integrated Multidisciplinary Analysis Tool, IMAT, that has been developed at NASA Langley Research Center. IMAT provides researchers and analysts with an efficient capability to analyze satellite control systems influenced by structural dynamics. Using a menu-driven interactive executive program, IMAT links a relational database to commercial structural and controls analysis codes. The paper describes the procedures followed to analyze a complex satellite structure and control system. The codes used to accomplish the analysis are described, and an example is provided of an application of IMAT to the analysis of a reference space station subject to a rectangular pulse loading at its docking port.

  12. Lasers and losers in the eyes of the law: liability for head and neck procedures.

    PubMed

    Svider, Peter F; Carron, Michael A; Zuliani, Giancarlo F; Eloy, Jean Anderson; Setzen, Michael; Folbe, Adam J

    2014-01-01

    Although some have noted that malpractice litigation may be "plateauing," defensive medical practices are pervasive and make up a considerable proportion of the "indirect" costs medicolegal issues contribute toward our health care system. Accordingly, these trends have spurred considerable interest in characterizing factors that play a role in alleged medical negligence, along with outcomes and awards. To conduct a focused examination of malpractice litigation regarding laser procedures in the head and neck and to determine the reasons for initiating litigation as well as outcomes and awards. Retrospective analysis of the WestlawNext legal database, encompassing publicly available federal and state court records, to identify malpractice cases involving laser procedures in the head and neck. Outcomes, awards, defendant specialty, and other allegations. Most cases (28 [82%]) included in this analysis involved female plaintiffs. Of 34 cases, 19 (56%) were resolved with a defendant verdict. The median indemnity was $150 000, and dermatologists, otolaryngologists, and plastic surgeons were the most commonly named defendants. The most common procedures were performed for age-related changes, acne scarring, hair removal, and vascular lesions, although there were also several rhinologic and airway cases. Of all cases, 25 (74%) involved cutaneous procedures, and common allegations noted included permanent injury (24 cases [71%]), disfigurement/scarring (23 [68%]), inadequate informed consent (17 [50%]), unnecessary/inappropriate procedure (15 [44%]), and burns (11 [32%]). Noncutaneous procedures had higher trending median payments ($600 000 vs $103 000), although this comparison did not reach statistical significance (P = .09). Procedures using lasers represent a potential target for malpractice litigation should an adverse event occur. Although cutaneous/cosmetic procedures were noted among cases included in this analysis, as well as other head and neck

  13. 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.

  14. Effectiveness of concurrent procedures during high tibial osteotomy for medial compartment osteoarthritis: a systematic review and meta-analysis.

    PubMed

    Lee, O-Sung; Ahn, Soyeon; Ahn, Jin Hwan; Teo, Seow Hui; Lee, Yong Seuk

    2018-02-01

    The purpose of this systematic review and meta-analysis was to evaluate the efficacy of concurrent cartilage procedures during high tibial osteotomy (HTO) for medial compartment osteoarthritis (OA) by comparing the outcomes of studies that directly compared the use of HTO plus concurrent cartilage procedures versus HTO alone. Results that are possible to be compared in more than two articles were presented as forest plots. A 95% confidence interval was calculated for each effect size, and we calculated the I 2 statistic, which presents the percentage of total variation attributable to the heterogeneity among studies. The random effects model was used to calculate the effect size. Seven articles were included to the final analysis. Case groups were composed of HTO without concurrent procedures and control groups were composed of HTO with concurrent procedures such as marrow stimulation procedure, mesenchymal stem cell transplantation, and injection. The case group showed a higher hospital for special surgery score and mean difference was 4.10 [I 2 80.8%, 95% confidence interval (CI) - 9.02 to 4.82]. Mean difference of the mechanical femorotibial angle in five studies was 0.08° (I 2 0%, 95% CI - 0.26 to 0.43). However, improved arthroscopic, histologic, and MRI results were reported in the control group. Our analysis support that concurrent procedures during HTO for medial compartment OA have little beneficial effect regarding clinical and radiological outcomes. However, they might have some beneficial effects in terms of arthroscopic, histologic, and MRI findings even though the quality of healed cartilage is not good as that of original cartilage. Therefore, until now, concurrent procedures for medial compartment OA have been considered optional. Nevertheless, no conclusions can be drawn for younger patients with focal cartilage defects and concomitant varus deformity. This question needs to be addressed separately.

  15. Safety and Performance Analysis of the Non-Radar Oceanic/Remote Airspace In-Trail Procedure

    NASA Technical Reports Server (NTRS)

    Carreno, Victor A.; Munoz, Cesar A.

    2007-01-01

    This document presents a safety and performance analysis of the nominal case for the In-Trail Procedure (ITP) in a non-radar oceanic/remote airspace. The analysis estimates the risk of collision between the aircraft performing the ITP and a reference aircraft. The risk of collision is only estimated for the ITP maneuver and it is based on nominal operating conditions. The analysis does not consider human error, communication error conditions, or the normal risk of flight present in current operations. The hazards associated with human error and communication errors are evaluated in an Operational Hazards Analysis presented elsewhere.

  16. Goals Analysis Procedure Guidelines for Applying the Goals Analysis Process

    NASA Technical Reports Server (NTRS)

    Motley, Albert E., III

    2000-01-01

    One of the key elements to successful project management is the establishment of the "right set of requirements", requirements that reflect the true customer needs and are consistent with the strategic goals and objectives of the participating organizations. A viable set of requirements implies that each individual requirement is a necessary element in satisfying the stated goals and that the entire set of requirements, taken as a whole, is sufficient to satisfy the stated goals. Unfortunately, it is the author's experience that during project formulation phases' many of the Systems Engineering customers do not conduct a rigorous analysis of the goals and objectives that drive the system requirements. As a result, the Systems Engineer is often provided with requirements that are vague, incomplete, and internally inconsistent. To complicate matters, most systems development methodologies assume that the customer provides unambiguous, comprehensive and concise requirements. This paper describes the specific steps of a Goals Analysis process applied by Systems Engineers at the NASA Langley Research Center during the formulation of requirements for research projects. The objective of Goals Analysis is to identify and explore all of the influencing factors that ultimately drive the system's requirements.

  17. A double-labeling procedure for sequence analysis of picomole amounts of nonradioactive RNA fragments.

    PubMed Central

    Gupta, R C; Randerath, E; Randerath, K

    1976-01-01

    A double-labeling procedure for sequence analysis of nonradioactive polyribonucleotides is detailed, which is based on controlled endonucleolytic degradation of 3'-terminally (3H)-labeled oligonucleotide-(3') dialcohols and 5"-terminal analysis of the partial (3H)-labeled fragments following their separation according to chain length by polyethyleneimine- (PEI-)cellulose TLC and detection by fluorography. Undesired nonradioactive partial digestion products are eliminated by periodate oxidation. The 5'-termini are assayed by enzymic incorporation of (32p)-label into the isolated fragments, enzymic release of (32p)-labeled nucleoside-(5') monophosphates, two-dimensional PEI-cellulose chromatography, and autoradiography. Using this procedure, as little as 0.1 - 0.3 A260 unit of tRNA is needed to sequence all fragments in complete ribonuclease T1 and A digests, whereas radioactive derivative methods previously described by us1-4 required 4 - 6 A260 units. Images PMID:826884

  18. From the operating room to the courtroom: a comprehensive characterization of litigation related to facial plastic surgery procedures.

    PubMed

    Svider, Peter F; Keeley, Brieze R; Zumba, Osvaldo; Mauro, Andrew C; Setzen, Michael; Eloy, Jean Anderson

    2013-08-01

    Malpractice litigation has increased in recent decades, contributing to higher health-care costs. Characterization of complications leading to litigation is of special interest to practitioners of facial plastic surgery procedures because of the higher proportion of elective cases relative to other subspecialties. In this analysis, we comprehensively examine malpractice litigation in facial plastic surgery procedures and characterize factors important in determining legal responsibility, as this information may be of great interest and use to practitioners in several specialties. Retrospective analysis. The Westlaw legal database was examined for court records pertaining to facial plastic surgery procedures. The term "medical malpractice" was searched in combination with numerous procedures obtained from the American Academy of Facial Plastic and Reconstructive Surgery website. Of the 88 cases included, 62.5% were decided in the physician's favor, 9.1% were resolved with an out-of-court settlement, and 28.4% ended in a jury awarding damages for malpractice. The mean settlement was $577,437 and mean jury award was $352,341. The most litigated procedures were blepharoplasties and rhinoplasties. Alleged lack of informed consent was noted in 38.6% of cases; other common complaints were excessive scarring/disfigurement, functional considerations, and postoperative pain. This analysis characterized factors in determining legal responsibility in facial plastic surgery cases. Several factors were identified as potential targets for minimizing liability. Informed consent was the most reported entity in these malpractice suits. This finding emphasizes the importance of open communication between physicians and their patients regarding expectations as well as documentation of specific risks, benefits, and alternatives. © 2013 The American Laryngological, Rhinological, and Otological Society, Inc.

  19. A Risk Analysis Methodology to Address Human and Organizational Factors in Offshore Drilling Safety: With an Emphasis on Negative Pressure Test

    NASA Astrophysics Data System (ADS)

    Tabibzadeh, Maryam

    According to the final Presidential National Commission report on the BP Deepwater Horizon (DWH) blowout, there is need to "integrate more sophisticated risk assessment and risk management practices" in the oil industry. Reviewing the literature of the offshore drilling industry indicates that most of the developed risk analysis methodologies do not fully and more importantly, systematically address the contribution of Human and Organizational Factors (HOFs) in accident causation. This is while results of a comprehensive study, from 1988 to 2005, of more than 600 well-documented major failures in offshore structures show that approximately 80% of those failures were due to HOFs. In addition, lack of safety culture, as an issue related to HOFs, have been identified as a common contributing cause of many accidents in this industry. This dissertation introduces an integrated risk analysis methodology to systematically assess the critical role of human and organizational factors in offshore drilling safety. The proposed methodology in this research focuses on a specific procedure called Negative Pressure Test (NPT), as the primary method to ascertain well integrity during offshore drilling, and analyzes the contributing causes of misinterpreting such a critical test. In addition, the case study of the BP Deepwater Horizon accident and their conducted NPT is discussed. The risk analysis methodology in this dissertation consists of three different approaches and their integration constitutes the big picture of my whole methodology. The first approach is the comparative analysis of a "standard" NPT, which is proposed by the author, with the test conducted by the DWH crew. This analysis contributes to identifying the involved discrepancies between the two test procedures. The second approach is a conceptual risk assessment framework to analyze the causal factors of the identified mismatches in the previous step, as the main contributors of negative pressure test

  20. A “Cookbook” Cost Analysis Procedure for Medical Information Systems*

    PubMed Central

    Torrance, Janice L.; Torrance, George W.; Covvey, H. Dominic

    1983-01-01

    A costing procedure for medical information systems is described. The procedure incorporates state-of-the-art costing methods in an easy to follow “cookbook” format. Application of the procedure consists of filling out a series of Mac-Tor EZ-Cost forms. The procedure and forms have been field tested by application to a cardiovascular database system. This article describes the major features of the costing procedure. The forms and other details are available upon request.

  1. General Staining and Segmentation Procedures for High Content Imaging and Analysis.

    PubMed

    Chambers, Kevin M; Mandavilli, Bhaskar S; Dolman, Nick J; Janes, Michael S

    2018-01-01

    Automated quantitative fluorescence microscopy, also known as high content imaging (HCI), is a rapidly growing analytical approach in cell biology. Because automated image analysis relies heavily on robust demarcation of cells and subcellular regions, reliable methods for labeling cells is a critical component of the HCI workflow. Labeling of cells for image segmentation is typically performed with fluorescent probes that bind DNA for nuclear-based cell demarcation or with those which react with proteins for image analysis based on whole cell staining. These reagents, along with instrument and software settings, play an important role in the successful segmentation of cells in a population for automated and quantitative image analysis. In this chapter, we describe standard procedures for labeling and image segmentation in both live and fixed cell samples. The chapter will also provide troubleshooting guidelines for some of the common problems associated with these aspects of HCI.

  2. Systematic Review of Factors Influencing Surgical Performance: Practical Recommendations for Microsurgical Procedures in Neurosurgery.

    PubMed

    Belykh, Evgenii; Onaka, Naomi R; Abramov, Irakliy T; Yağmurlu, Kaan; Byvaltsev, Vadim A; Spetzler, Robert F; Nakaj, Peter; Preul, Mark C

    2018-04-01

    Microneurosurgical techniques involve complex manual skills and hand-eye coordination that require substantial training. Many factors affect microneurosurgical skills. The goal of this study was to use a systematic evidence-based approach to analyze the quality of evidence for intrinsic and extrinsic factors that influence microneurosurgical performance and to make weighted practical recommendations. A literature search of factors that may affect microsurgical performance was conducted using PubMed and Embase. The criteria for inclusion were established in accordance with the PRISMA-P (Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols) statement. Forty-eight studies were included in the analysis. Most of the studies used surgeons as participants. Most used endoscopic surgery simulators to assess skills, and only 12 studies focused on microsurgery. This review provides 18 practical recommendations based on a systematic literature analysis of the following 8 domains: 1) listening to music before and during microsurgery, 2) caffeine consumption, 3) β-blocker use, 4) physical exercise, 5) sleep deprivation, 6) alcohol consumption before performing surgery, 7) duration of the operation, and 8) the ergonomic position of the surgeon. Despite the clear value of determining the effects of various factors on surgical performance, the available body of literature is limited, and it is not possible to determine standards for each surgical field. These recommendations may be used by neurosurgical trainees and practicing neurosurgeons to improve microsurgical performance and acquisition of microsurgical skills. Randomized studies assessing the factors that influence microsurgical performance are required. Copyright © 2018 Elsevier Inc. All rights reserved.

  3. Recurrent-neural-network-based Boolean factor analysis and its application to word clustering.

    PubMed

    Frolov, Alexander A; Husek, Dusan; Polyakov, Pavel Yu

    2009-07-01

    The objective of this paper is to introduce a neural-network-based algorithm for word clustering as an extension of the neural-network-based Boolean factor analysis algorithm (Frolov , 2007). It is shown that this extended algorithm supports even the more complex model of signals that are supposed to be related to textual documents. It is hypothesized that every topic in textual data is characterized by a set of words which coherently appear in documents dedicated to a given topic. The appearance of each word in a document is coded by the activity of a particular neuron. In accordance with the Hebbian learning rule implemented in the network, sets of coherently appearing words (treated as factors) create tightly connected groups of neurons, hence, revealing them as attractors of the network dynamics. The found factors are eliminated from the network memory by the Hebbian unlearning rule facilitating the search of other factors. Topics related to the found sets of words can be identified based on the words' semantics. To make the method complete, a special technique based on a Bayesian procedure has been developed for the following purposes: first, to provide a complete description of factors in terms of component probability, and second, to enhance the accuracy of classification of signals to determine whether it contains the factor. Since it is assumed that every word may possibly contribute to several topics, the proposed method might be related to the method of fuzzy clustering. In this paper, we show that the results of Boolean factor analysis and fuzzy clustering are not contradictory, but complementary. To demonstrate the capabilities of this attempt, the method is applied to two types of textual data on neural networks in two different languages. The obtained topics and corresponding words are at a good level of agreement despite the fact that identical topics in Russian and English conferences contain different sets of keywords.

  4. Functional and Structural Analyses of Behavior: Approaches Leading to Reduced Use of Punishment Procedures?

    ERIC Educational Resources Information Center

    Axelrod, Saul

    1987-01-01

    Emerging approaches for dealing with inappropriate behaviors of the disabled involve conducting a functional or structural behavior analysis to isolate the factors responsible for the aberrant behavior and implementing corrective procedures (often alternatives to punishment) relevant to the function of the inappropriate behavior. (Author/DB)

  5. Unanticipated hospital admission in pediatric patients with congenital heart disease undergoing ambulatory noncardiac surgical procedures.

    PubMed

    Yuki, Koichi; Koutsogiannaki, Sophia; Lee, Sandra; DiNardo, James A

    2018-05-18

    An increasing number of surgical and nonsurgical procedures are being performed on an ambulatory basis in children. Analysis of a large group of pediatric patients with congenital heart disease undergoing ambulatory procedures has not been undertaken. The objective of this study was to characterize the profile of children with congenital heart disease who underwent noncardiac procedures on an ambulatory basis at our institution, to determine the incidence of adverse cardiovascular and respiratory adverse events, and to determine the risk factors for unscheduled hospital admission. This is a retrospective study of children with congenital heart disease who underwent noncardiac procedures on an ambulatory basis in a single center. Using the electronic preoperative anesthesia evaluation form, we identified 3010 patients with congenital heart disease who underwent noncardiac procedures of which 1028 (34.1%) were scheduled to occur on an ambulatory basis. Demographic, echocardiographic and functional status data, cardiovascular and respiratory adverse events, and reasons for postprocedure admission were recorded. Univariable analysis was conducted. The unplanned hospital admission was 2.7% and univariable analysis demonstrated that performance of an echocardiogram within 6 mo of the procedure and procedures performed in radiology were associated with postoperative admission. Cardiovascular adverse event incidence was 3.9%. Respiratory adverse event incidence was 1.8%. Ambulatory, noncomplex procedures can be performed in pediatric patients with congenital heart disease and good functional status with a relatively low unanticipated hospital admission rate. © 2018 John Wiley & Sons Ltd.

  6. Forensic analysis of Salvia divinorum using multivariate statistical procedures. Part I: discrimination from related Salvia species.

    PubMed

    Willard, Melissa A Bodnar; McGuffin, Victoria L; Smith, Ruth Waddell

    2012-01-01

    Salvia divinorum is a hallucinogenic herb that is internationally regulated. In this study, salvinorin A, the active compound in S. divinorum, was extracted from S. divinorum plant leaves using a 5-min extraction with dichloromethane. Four additional Salvia species (Salvia officinalis, Salvia guaranitica, Salvia splendens, and Salvia nemorosa) were extracted using this procedure, and all extracts were analyzed by gas chromatography-mass spectrometry. Differentiation of S. divinorum from other Salvia species was successful based on visual assessment of the resulting chromatograms. To provide a more objective comparison, the total ion chromatograms (TICs) were subjected to principal components analysis (PCA). Prior to PCA, the TICs were subjected to a series of data pretreatment procedures to minimize non-chemical sources of variance in the data set. Successful discrimination of S. divinorum from the other four Salvia species was possible based on visual assessment of the PCA scores plot. To provide a numerical assessment of the discrimination, a series of statistical procedures such as Euclidean distance measurement, hierarchical cluster analysis, Student's t tests, Wilcoxon rank-sum tests, and Pearson product moment correlation were also applied to the PCA scores. The statistical procedures were then compared to determine the advantages and disadvantages for forensic applications.

  7. A comparison study on detection of key geochemical variables and factors through three different types of factor analysis

    NASA Astrophysics Data System (ADS)

    Hoseinzade, Zohre; Mokhtari, Ahmad Reza

    2017-10-01

    Large numbers of variables have been measured to explain different phenomena. Factor analysis has widely been used in order to reduce the dimension of datasets. Additionally, the technique has been employed to highlight underlying factors hidden in a complex system. As geochemical studies benefit from multivariate assays, application of this method is widespread in geochemistry. However, the conventional protocols in implementing factor analysis have some drawbacks in spite of their advantages. In the present study, a geochemical dataset including 804 soil samples collected from a mining area in central Iran in order to search for MVT type Pb-Zn deposits was considered to outline geochemical analysis through various fractal methods. Routine factor analysis, sequential factor analysis, and staged factor analysis were applied to the dataset after opening the data with (additive logratio) alr-transformation to extract mineralization factor in the dataset. A comparison between these methods indicated that sequential factor analysis has more clearly revealed MVT paragenesis elements in surface samples with nearly 50% variation in F1. In addition, staged factor analysis has given acceptable results while it is easy to practice. It could detect mineralization related elements while larger factor loadings are given to these elements resulting in better pronunciation of mineralization.

  8. Job compensable factors and factor weights derived from job analysis data.

    PubMed

    Chi, Chia-Fen; Chang, Tin-Chang; Hsia, Ping-Ling; Song, Jen-Chieh

    2007-06-01

    Government data on 1,039 job titles in Taiwan were analyzed to assess possible relationships between job attributes and compensation. For each job title, 79 specific variables in six major classes (required education and experience, aptitude, interest, work temperament, physical demands, task environment) were coded to derive the statistical predictors of wage for managers, professionals, technical, clerical, service, farm, craft, operatives, and other workers. Of the 79 variables, only 23 significantly related to pay rate were subjected to a factor and multiple regression analysis for predicting monthly wages. Given the heterogeneous nature of collected job titles, a 4-factor solution (occupational knowledge and skills, human relations skills, work schedule hardships, physical hardships) explaining 43.8% of the total variance but predicting only 23.7% of the monthly pay rate was derived. On the other hand, multiple regression with 9 job analysis items (required education, professional training, professional certificate, professional experience, coordinating, leadership and directing, demand on hearing, proportion of shift working indoors, outdoors and others, rotating shift) better predicted pay and explained 32.5% of the variance. A direct comparison of factors and subfactors of job evaluation plans indicated mental effort and responsibility (accountability) had not been measured with the current job analysis data. Cross-validation of job evaluation factors and ratings with the wage rates is required to calibrate both.

  9. Exchange nailing for nonunion of diaphyseal fractures of the tibia: our results and an analysis of the risk factors for failure.

    PubMed

    Tsang, S T J; Mills, L A; Frantzias, J; Baren, J P; Keating, J F; Simpson, A H R W

    2016-04-01

    The aim of this study was to identify risk factors for the failure of exchange nailing in nonunion of tibial diaphyseal fractures. A cohort of 102 tibial diaphyseal nonunions in 101 patients with a mean age of 36.9 years (15 to 74) were treated between January 1992 and December 2012 by exchange nailing. Of which 33 (32%) were initially open injuries. The median time from primary fixation to exchange nailing was 6.5 months (interquartile range (IQR) 4.3 to 9.8 months). The main outcome measures were union, number of secondary fixation procedures required to achieve union and time to union. Univariate analysis and multiple regression were used to identify risk factors for failure to achieve union. Multiple causes for the primary nonunion were found for 28 (27%) tibiae, with infection present in 32 (31%). Six patients were lost to follow-up. Further surgical procedures were required in 35 (36%) nonunions. Other fixation modalities were required in five fractures. A single nail exchange procedure achieved union in 60/96 (63%) of all nonunions. Only 11 out of 31 infected nonunions (35.4%) healed after one exchange nail procedure. Up to five repeated exchange nailings, with or without bone grafting, ultimately achieved union in 89 (93%) fractures. The median time to union after exchange nailing was 8.7 months (IQR 5.7 to 14.0 months). Univariate analysis confirmed that an oligotrophic/atrophic pattern of nonunion (p = 0.002), a bone gap of 5 mm or more (p = 0.04) and infection (p < 0.001), were predictive for failure of exchange nailing Multiple regression analysis found that infection was the strongest predictor of failure (p < 0.001). Exchange nailing is an effective treatment for aseptic tibial diaphyseal nonunion. However, in the presence of severe infection with a highly resistant organism, or extensive sclerosis of the bone, other fixation modalities, such as Ilizarov treatment, should be considered. Exchange nailing is an effective treatment for aseptic tibial

  10. Photo point monitoring handbook—Part A: Field procedures; Part B: Concepts and analysis.

    Treesearch

    Frederick C. Hall

    2002-01-01

    This handbook describes quick, effective methods for documenting change in vegetation and soil through repeat photography. It is published in two parts: field procedures in part A and concepts and office analysis in part B. Topics may be effects of logging, change in wildlife habitat, livestock grazing impacts, or stream channel reaction to land management. Land...

  11. Depth of anaesthesia monitoring during procedural sedation and analgesia: A systematic review and meta-analysis.

    PubMed

    Conway, Aaron; Sutherland, Joanna

    2016-11-01

    Processed electroencephalogram-based depth of anaesthesia monitoring devices provide an additional method to monitor level of consciousness during procedural sedation and analgesia. The objective of this systematic review was to determine whether using a depth of anaesthesia monitoring device improves the safety and efficacy of sedation. Systematic review and meta-analysis. Electronic databases (CENTRAL; Medline; CINAHL) were searched up to May 2015. Randomised controlled trials that compared use of a depth of anaesthesia monitoring device to a control group who received standard monitoring during procedural sedation and analgesia were included. Study selection, data extraction and risk of bias assessment (Cochrane risk of bias tool) were performed by two reviewers. Safety outcomes were hypoxaemia, hypotension and adverse events. Efficacy outcomes were amount of sedation used, duration of sedation recovery and rate of incomplete procedures. A total of 16 trials (2138 participants) were included. Evidence ratings were downgraded to either low or moderate quality due to study limitations and imprecision. Meta-analysis of 8 trials (766 participants) found no difference in hypoxaemia (RR 0.87; 95% CI=0.67-1.12). No statistically significant difference in hypotension was observed in meta-analysis of 8 trials (RR 0.96; 95% CI=0.54-1.7; 942 participants). Mean dose of propofol was 51mg lower for participants randomised to depth of anaesthesia monitoring (95% CI=-88.7 to -13.3mg) in meta-analysis of results from four trials conducted with 434 participants who underwent interventional endoscopy procedures with propofol infusions to maintain sedation. The difference in recovery time between depth of anaesthesia and standard monitoring groups was not clinically significant (standardised mean difference -0.41; 95% CI=-0.8 to -0.02; I 2 =86%; 8 trials; 809 participants). Depth of anaesthesia monitoring did impact sedation titration during interventional procedures with propofol

  12. Risk factors for pedicled flap necrosis in hand soft tissue reconstruction: a multivariate logistic regression analysis.

    PubMed

    Gong, Xu; Cui, Jianli; Jiang, Ziping; Lu, Laijin; Li, Xiucun

    2018-03-01

    Few clinical retrospective studies have reported the risk factors of pedicled flap necrosis in hand soft tissue reconstruction. The aim of this study was to identify non-technical risk factors associated with pedicled flap perioperative necrosis in hand soft tissue reconstruction via a multivariate logistic regression analysis. For patients with hand soft tissue reconstruction, we carefully reviewed hospital records and identified 163 patients who met the inclusion criteria. The characteristics of these patients, flap transfer procedures and postoperative complications were recorded. Eleven predictors were identified. The correlations between pedicled flap necrosis and risk factors were analysed using a logistic regression model. Of 163 skin flaps, 125 flaps survived completely without any complications. The pedicled flap necrosis rate in hands was 11.04%, which included partial flap necrosis (7.36%) and total flap necrosis (3.68%). Soft tissue defects in fingers were noted in 68.10% of all cases. The logistic regression analysis indicated that the soft tissue defect site (P = 0.046, odds ratio (OR) = 0.079, confidence interval (CI) (0.006, 0.959)), flap size (P = 0.020, OR = 1.024, CI (1.004, 1.045)) and postoperative wound infection (P < 0.001, OR = 17.407, CI (3.821, 79.303)) were statistically significant risk factors for pedicled flap necrosis of the hand. Soft tissue defect site, flap size and postoperative wound infection were risk factors associated with pedicled flap necrosis in hand soft tissue defect reconstruction. © 2017 Royal Australasian College of Surgeons.

  13. Identification of risk factors for mucosal injury during laparoscopic Heller myotomy for achalasia.

    PubMed

    Tsuboi, Kazuto; Omura, Nobuo; Yano, Fumiaki; Hoshino, Masato; Yamamoto, Se-Ryung; Akimoto, Shusuke; Masuda, Takahiro; Kashiwagi, Hideyuki; Yanaga, Katsuhiko

    2016-02-01

    Mucosal injury during myotomy is the most frequent complication seen with the Heller-Dor procedure for achalasia. The present study aimed to examine risk factors for such mucosal injury during this procedure. This was a retrospective analysis of patients who underwent the laparoscopic Heller-Dor procedure for achalasia at a single facility. Variables for evaluation included patient characteristics, preoperative pathophysiological findings, and surgeon's operative experience. Logistic regression was used to identify risk factors. We also examined surgical outcomes and the degree of patient satisfaction in relation to intraoperative mucosal injury. Four hundred thirty-five patients satisfied study criteria. Intraoperative mucosal injury occurred in 67 patients (15.4%). In univariate analysis, mucosal injury was significantly associated with the patient age ≥60 years, disease history ≥10 years, prior history of cardiac diseases, preoperative esophageal transverse diameter ≥80 mm, and surgeon's operative experience with fewer than five cases. In multivariate analysis involving these factors, the following variables were identified as risk factors: age ≥60 years, esophageal transverse diameter ≥80 mm, and surgeon's operative experience with fewer than five cases. The mucosal injury group had significant extension of the operative time and increased blood loss. However, there were no significant differences between the two groups in the incidence of reflux esophagitis or the degree of symptom alleviation postoperatively. The fragile esophagus caused by advanced patient age and/or dilatation were risk factor for mucosal injury during laparoscopic Heller-Dor procedure. And novice surgeon was also identified as an isolated risk factor for mucosal injury.

  14. Settlements around pumping wells: Analysis of influential factors and a simple calculation procedure

    NASA Astrophysics Data System (ADS)

    Pujades, Estanislao; De Simone, Silvia; Carrera, Jesus; Vázquez-Suñé, Enric; Jurado, Anna

    2017-05-01

    Estimated and measured settlements caused by pumping rarely agree. Several reasons could explain this mismatch, including the influence of layering, the mechanical parameters used in the predictions, or the relationship between settlements and drawdown. We analyze the influence of the above issues by investigating the mechanical response of pumped elastic porous media under different conditions. A radially symmetric conceptual model is considered and several hydro-mechanical simulations are performed varying the boundary conditions, the size of the modeled domain and the presence or not of an overlying layer. The simplicity of the considered problem allows us to compare our results with existing analytical solutions, to identify the role of each variable on pumping settlements and to generalize the results. The most relevant results are as follows: (1) settlements are proportional to drawdown only outside a circle of radius equal to 0.7 times the thickness of the pumped porous medium; inside, they are virtually constant, which leads to two simple procedures for computing pumping settlements. (2) Poorly conductive layers located above (or below) a pumped porous medium (with higher hydraulic conductivity) reduce and smooth settlements. (3) Boundary constraints affect the local specific storage coefficient and the displacements occurred. (4) The specific storage coefficient evaluated by interpreting pumping tests with the Cooper and Jacob method (1946) leads to overestimation of the actual Young's Modulus of the soil. The main conclusion is that settlements are less differential than expected near pumping wells. Still, they must always be evaluated acknowledging the nature of layering, the boundary constraints and carefully selecting the mechanical parameters of the soil.

  15. Using BMDP and SPSS for a Q factor analysis.

    PubMed

    Tanner, B A; Koning, S M

    1980-12-01

    While Euclidean distances and Q factor analysis may sometimes be preferred to correlation coefficients and cluster analysis for developing a typology, commercially available software does not always facilitate their use. Commands are provided for using BMDP and SPSS in a Q factor analysis with Euclidean distances.

  16. The interval testing procedure: A general framework for inference in functional data analysis.

    PubMed

    Pini, Alessia; Vantini, Simone

    2016-09-01

    We introduce in this work the Interval Testing Procedure (ITP), a novel inferential technique for functional data. The procedure can be used to test different functional hypotheses, e.g., distributional equality between two or more functional populations, equality of mean function of a functional population to a reference. ITP involves three steps: (i) the representation of data on a (possibly high-dimensional) functional basis; (ii) the test of each possible set of consecutive basis coefficients; (iii) the computation of the adjusted p-values associated to each basis component, by means of a new strategy here proposed. We define a new type of error control, the interval-wise control of the family wise error rate, particularly suited for functional data. We show that ITP is provided with such a control. A simulation study comparing ITP with other testing procedures is reported. ITP is then applied to the analysis of hemodynamical features involved with cerebral aneurysm pathology. ITP is implemented in the fdatest R package. © 2016, The International Biometric Society.

  17. Laboratory Analytical Procedures | Bioenergy | NREL

    Science.gov Websites

    analytical procedures (LAPs) to provide validated methods for biofuels and pyrolysis bio-oils research . Biomass Compositional Analysis These lab procedures provide tested and accepted methods for performing

  18. Standard operating procedures, water immersion facility, revision B

    NASA Technical Reports Server (NTRS)

    1979-01-01

    General guideline procedures to identify those factors that are common to all spacecraft design laboratory support group emergency procedures and to establish the basic rescue plan are presented. This eliminates needless repetition of the fundamentals from the other, more specific procedures.

  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. Human factors research plan for instrument procedures : FY12 version 1.1

    DOT National Transportation Integrated Search

    2012-06-19

    This research will support the development of instrument procedures for performance-based navigation (PBN) operations. These procedures include, but are not limited to, area navigation (RNAV) and required navigation performance (RNP) operations. The ...

  1. Application of statistical process control and process capability analysis procedures in orbiter processing activities at the Kennedy Space Center

    NASA Technical Reports Server (NTRS)

    Safford, Robert R.; Jackson, Andrew E.; Swart, William W.; Barth, Timothy S.

    1994-01-01

    Successful ground processing at KSC requires that flight hardware and ground support equipment conform to specifications at tens of thousands of checkpoints. Knowledge of conformance is an essential requirement for launch. That knowledge of conformance at every requisite point does not, however, enable identification of past problems with equipment, or potential problem areas. This paper describes how the introduction of Statistical Process Control and Process Capability Analysis identification procedures into existing shuttle processing procedures can enable identification of potential problem areas and candidates for improvements to increase processing performance measures. Results of a case study describing application of the analysis procedures to Thermal Protection System processing are used to illustrate the benefits of the approaches described in the paper.

  2. Measuring cognitive load during procedural skills training with colonoscopy as an exemplar.

    PubMed

    Sewell, Justin L; Boscardin, Christy K; Young, John Q; Ten Cate, Olle; O'Sullivan, Patricia S

    2016-06-01

    Few studies have investigated cognitive factors affecting learning of procedural skills in medical education. Cognitive load theory, which focuses on working memory, is highly relevant, but methods for measuring cognitive load during procedural training are not well understood. Using colonoscopy as an exemplar, we used cognitive load theory to develop a self-report instrument to measure three types of cognitive load (intrinsic, extraneous and germane load) and to provide evidence for instrument validity. We developed the instrument (the Cognitive Load Inventory for Colonoscopy [CLIC]) using a multi-step process. It included 19 items measuring three types of cognitive load, three global rating items and demographics. We then conducted a cross-sectional survey that was administered electronically to 1061 gastroenterology trainees in the USA. Participants completed the CLIC following a colonoscopy. The two study phases (exploratory and confirmatory) each lasted for 10 weeks during the 2014-2015 academic year. Exploratory factor analysis determined the most parsimonious factor structure; confirmatory factor analysis assessed model fit. Composite measures of intrinsic, extraneous and germane load were compared across years of training and with global rating items. A total of 477 (45.0%) invitees participated (116 in the exploratory study and 361 in the confirmatory study) in 154 (95.1%) training programmes. Demographics were similar to national data from the USA. The most parsimonious factor structure included three factors reflecting the three types of cognitive load. Confirmatory factor analysis verified that a three-factor model was the best fit. Intrinsic, extraneous and germane load items had high internal consistency (Cronbach's alpha 0.90, 0.87 and 0.96, respectively) and correlated as expected with year in training and global assessment of cognitive load. The CLIC measures three types of cognitive load during colonoscopy training. Evidence of validity is

  3. Data and analysis procedures for improved aerial applications mission performance. [agricultural aircraft wing geometry

    NASA Technical Reports Server (NTRS)

    Holmes, B. J.; Morris, D. K.; Razak, K.

    1979-01-01

    An analysis procedure is given and cases analyzed for the effects of wing geometry on lateral transport of a variety of agricultural particles released in the wake of an agricultural airplane. The cases analyzed simulate the release of particles from a fuselage centerline-mounted dry material spreader; however, the procedure applies to particles released anywhere along the wing span. Consideration is given to the effects of taper ratio, aspect ratio, wing loading, and deflected flaps. It is noted that significant lateral transport of large particles can be achieved using high-lift devices positioned to create a strong vortex near the location of particle release.

  4. User's operating procedures. Volume 2: Scout project financial analysis program

    NASA Technical Reports Server (NTRS)

    Harris, C. G.; Haris, D. K.

    1985-01-01

    A review is presented of the user's operating procedures for the Scout Project Automatic Data system, called SPADS. SPADS is the result of the past seven years of software development on a Prime mini-computer located at the Scout Project Office, NASA Langley Research Center, Hampton, Virginia. SPADS was developed as a single entry, multiple cross-reference data management and information retrieval system for the automation of Project office tasks, including engineering, financial, managerial, and clerical support. This volume, two (2) of three (3), provides the instructions to operate the Scout Project Financial Analysis program in data retrieval and file maintenance via the user friendly menu drivers.

  5. Reduction procedures for accurate analysis of MSX surveillance experiment data

    NASA Technical Reports Server (NTRS)

    Gaposchkin, E. Mike; Lane, Mark T.; Abbot, Rick I.

    1994-01-01

    Technical challenges of the Midcourse Space Experiment (MSX) science instruments require careful characterization and calibration of these sensors for analysis of surveillance experiment data. Procedures for reduction of Resident Space Object (RSO) detections will be presented which include refinement and calibration of the metric and radiometric (and photometric) data and calculation of a precise MSX ephemeris. Examples will be given which support the reduction, and these are taken from ground-test data similar in characteristics to the MSX sensors and from the IRAS satellite RSO detections. Examples to demonstrate the calculation of a precise ephemeris will be provided from satellites in similar orbits which are equipped with S-band transponders.

  6. What School Psychologists Need to Know about Factor Analysis

    ERIC Educational Resources Information Center

    McGill, Ryan J.; Dombrowski, Stefan C.

    2017-01-01

    Factor analysis is a versatile class of psychometric techniques used by researchers to provide insight into the psychological dimensions (factors) that may account for the relationships among variables in a given dataset. The primary goal of a factor analysis is to determine a more parsimonious set of variables (i.e., fewer than the number of…

  7. A comparison of the Monti and spiral Monti procedures: A long-term analysis.

    PubMed

    Whittam, B M; Szymanski, K M; Flack, C; Misseri, R; Kaefer, M; Rink, R C; Cain, M P

    2015-06-01

    The Monti ileovesicostomy provides an excellent substitution for an appendicovesicostomy when the appendix is unavailable or suitable for use. The spiral Monti is a useful modification to the traditional Monti as it allows creation of a longer channel when needed. In 2007, the short-term outcomes were reported; they compared traditional and spiral Monti in 188 patients with an average follow-up of 43 months. In the present population, a total of 25 subfasical revisions were performed in 21 patients: nine (8.3%) subfascial revisions in the traditional Monti (TM) patients and 12 (15.2%) subfascial revisions in the spiral Monti (SM) patients. The study found an increased risk of subfascial revisions of either TM or SM when the stoma was located at the umbilicus versus right lower quadrant (16.8% vs 6.3%, P < 0.05). On subgroup analysis, this increased subfascial revision rate appeared to be driven by SM channels to the umbilicus rather than other stomal locations, but this trend was not statistically significant. It was hypothesized that with longer follow-up, the spiral Monti would require more subfascial revisions due to progressive lengthening of the channel. A retrospective chart review was performed for all patients undergoing a traditional Monti (TM) or spiral Monti (SM) procedure at the present institution (1997-2013). Patient demographics, bowel segment used, stomal location, channel or stomal revisions, number of anesthetic endoscopic procedures performed, and indications for revision were reviewed. Kaplan-Meier analysis and Cox proportional hazards modeling was used for analysis. Of the 296 patients identified, 146 had Monti procedures and 150 had spiral Monti procedures (median follow-up 7.7 years). Median age at surgery was 10.6 years. Myelomeningocele was the most common underlying cause of neuropathic bladder, totaling 169 (57.1%) patients. Stomas were located at the umbilicus (106, 35.8%), right lower quadrant (183, 61.8%) and left lower quadrant (seven

  8. 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)…

  9. 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,…

  10. Assessment of economic factors affecting the satellite power system. Volume 1: System cost factors

    NASA Technical Reports Server (NTRS)

    Hazelrigg, G. A., Jr.

    1978-01-01

    The factors relevant to SPS costing and selection of preferred SPS satellite configurations were studied. The issues discussed are: (1) consideration of economic factors in the SPS system that relate to selection of SPS satellite configuration; (2) analysis of the proper rate of interest for use in SPS system definition studies; and (3) the impacts of differential inflation on SPS system definition costing procedures. A cost-risk comparison of the SPS satellite configurations showed a significant difference in the levelized cost of power from them. It is concluded, that this difference is the result more of differences in the procedures for assessing costs rather than in the satellite technologies required or of any advantages of one satellite configuration over the other. Analysis of the proper rate of interest for use in SPS system is 4 percent. The major item of differential inflation to be expected over this period of time is the real cost of labor. This cost is likely to double between today and the period of SPS construction.

  11. Development of a thermal and structural analysis procedure for cooled radial turbines

    NASA Technical Reports Server (NTRS)

    Kumar, Ganesh N.; Deanna, Russell G.

    1988-01-01

    A procedure for computing the rotor temperature and stress distributions in a cooled radial turbine is considered. Existing codes for modeling the external mainstream flow and the internal cooling flow are used to compute boundary conditions for the heat transfer and stress analyses. An inviscid, quasi three-dimensional code computes the external free stream velocity. The external velocity is then used in a boundary layer analysis to compute the external heat transfer coefficients. Coolant temperatures are computed by a viscous one-dimensional internal flow code for the momentum and energy equation. These boundary conditions are input to a three-dimensional heat conduction code for calculation of rotor temperatures. The rotor stress distribution may be determined for the given thermal, pressure and centrifugal loading. The procedure is applied to a cooled radial turbine which will be tested at the NASA Lewis Research Center. Representative results from this case are included.

  12. Genomic Sequencing Procedure Microcosting Analysis and Health Economic Cost-Impact Analysis: A Report of the Association for Molecular Pathology.

    PubMed

    Sabatini, Linda M; Mathews, Charles; Ptak, Devon; Doshi, Shivang; Tynan, Katherine; Hegde, Madhuri R; Burke, Tara L; Bossler, Aaron D

    2016-05-01

    The increasing use of advanced nucleic acid sequencing technologies for clinical diagnostics and therapeutics has made vital understanding the costs of performing these procedures and their value to patients, providers, and payers. The Association for Molecular Pathology invested in a cost and value analysis of specific genomic sequencing procedures (GSPs) newly coded by the American Medical Association Current Procedural Terminology Editorial Panel. Cost data and work effort, including the development and use of data analysis pipelines, were gathered from representative laboratories currently performing these GSPs. Results were aggregated to generate representative cost ranges given the complexity and variability of performing the tests. Cost-impact models for three clinical scenarios were generated with assistance from key opinion leaders: impact of using a targeted gene panel in optimizing care for patients with advanced non-small-cell lung cancer, use of a targeted gene panel in the diagnosis and management of patients with sensorineural hearing loss, and exome sequencing in the diagnosis and management of children with neurodevelopmental disorders of unknown genetic etiology. Each model demonstrated value by either reducing health care costs or identifying appropriate care pathways. The templates generated will aid laboratories in assessing their individual costs, considering the value structure in their own patient populations, and contributing their data to the ongoing dialogue regarding the impact of GSPs on improving patient care. Copyright © 2016 American Society for Investigative Pathology and the Association for Molecular Pathology. Published by Elsevier Inc. All rights reserved.

  13. Factors affecting successful colonoscopy procedures: Single-center experience.

    PubMed

    Kozan, Ramazan; Yılmaz, Tonguç Utku; Baştuğral, Uygar; Kerimoğlu, Umut; Yavuz, Yücel

    2018-01-01

    Colonoscopy is a gold standard procedure for several colon pathologies. Successful colonoscopy means demonstration of the ileocecal valve and determination of colon polyps. Here we aimed to evaluate our colonoscopy success and results. This retrospective descriptive study was performed in İstanbul Eren hospital endoscopy unit between 2012 and 2015. Colonoscopy results and patient demographics were obtained from the hospital database. All colonoscopy procedures were performed under general anesthesia and after full bowel preparation. In all, 870 patients were included to the study. We reached to the cecum in 850 (97.8%) patients. We were unable to reach the cecum in patients who were old and obese and those with previous lower abdominal operations. Angulation, inability to move forward, and tortuous colon were the reasons for inability to reach the cecum. Total 203 polyp samplings were performed in 139 patients. We performed 1, 2, and 3 polypectomies in 97, 28, and 10 patients, respectively. There were 29 (3.3%) colorectal cancers in our series. There was no mortality or morbidity in our study. General anesthesia and full bowel preparation may be the reason for increased success of colonoscopy. Increased experience and patient-endoscopist cooperation increased the rate of cecum access and polyp resection and decreased the complication rate.

  14. 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…

  15. Identification of modifiable factors for reducing readmission after colectomy: a national analysis.

    PubMed

    Lawson, Elise H; Hall, Bruce Lee; Louie, Rachel; Zingmond, David S; Ko, Clifford Y

    2014-05-01

    Rates of hospital readmission are currently used for public reporting and pay for performance. Colectomy procedures account for a large number of readmissions among operative procedures. Our objective was to compare the importance of 3 groups of clinical variables (demographics, preoperative risk factors, and postoperative complications) in predicting readmission after colectomy procedures. Patient records (2005-2008) from the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) were linked to Medicare inpatient claims. Patient demographics (n = 2), preoperative risk factors (n = 23), and 30-day postoperative complications (n = 17) were identified from ACS-NSQIP, whereas 30-day postoperative readmissions and costs were determined from Medicare. Multivariable logistic regression models were used to examine risk-adjusted predictors of colectomy readmission. Among 12,981 colectomy patients, the 30-day postoperative readmission rate was 13.5%. Readmitted patients had slightly greater rates of comorbidities and indicators of clinical severity and substantially greater rates of complications than non-readmitted patients. After risk adjustment, patients with a complication were 3.3 times as likely to be readmitted as patients without a complication. Among individual complications, progressive renal failure and organ-space surgical site infection had the highest risk-adjusted relative risks of readmission (4.6 and 4.0, respectively). Demographic, preoperative risk factor, and postoperative complication variables increased the ability to discriminate readmissions (reflected by the c-statistic) by 5.3%, 23.3%, and 35.4%, respectively. Postoperative complications after colectomy are more predictive of readmission than traditional risk factors. Focusing quality improvement efforts on preventing and managing postoperative complications may be the most important step toward reducing readmission rates. Copyright © 2014 Mosby, Inc. All rights

  16. Proportion of general factor variance in a hierarchical multiple-component measuring instrument: a note on a confidence interval estimation procedure.

    PubMed

    Raykov, Tenko; Zinbarg, Richard E

    2011-05-01

    A confidence interval construction procedure for the proportion of explained variance by a hierarchical, general factor in a multi-component measuring instrument is outlined. The method provides point and interval estimates for the proportion of total scale score variance that is accounted for by the general factor, which could be viewed as common to all components. The approach may also be used for testing composite (one-tailed) or simple hypotheses about this proportion, and is illustrated with a pair of examples. ©2010 The British Psychological Society.

  17. Comprehensive evaluation of liver resection procedures: surgical mind development through cognitive task analysis

    PubMed Central

    Wakabayashi, Go; Yeh, Chi-Chuan; Hu, Rey-Heng; Sakaguchi, Takanori; Hasegawa, Yasushi; Takahara, Takeshi; Nitta, Hiroyuki; Sasaki, Akira; Lee, Po-Huang

    2018-01-01

    Background Liver resection is a complex procedure for trainee surgeons. Cognitive task analysis (CTA) facilitates understanding and decomposing tasks that require a great proportion of mental activity from experts. Methods Using CTA and video-based coaching to compare liver resection by open and laparoscopic approaches, we decomposed the task of liver resection into exposure (visual field building), adequate tension made at the working plane (which may change three-dimensionally during the resection process), and target processing (intervention strategy) that can bridge the gap from the basic surgical principle. Results The key steps of highly-specialized techniques, including hanging maneuvers and looping of extra-hepatic hepatic veins, were shown on video by open and laparoscopic approaches. Conclusions Familiarization with laparoscopic anatomical orientation may help surgeons already skilled at open liver resection transit to perform laparoscopic liver resection smoothly. Facilities at hand (such as patient tolerability, advanced instruments, and trained teams of personnel) can influence surgical decision making. Application of the rationale and realizing the interplay between the surgical principles and the other paramedical factors may help surgeons in training to understand the mental abstractions of experienced surgeons, to choose the most appropriate surgical strategy effectively at will, and to minimize the gap. PMID:29445607

  18. 76 FR 77742 - Guidelines Establishing Test Procedures for the Analysis of Pollutants Under the Clean Water Act...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-14

    ... ENVIRONMENTAL PROTECTION AGENCY 40 CFR Part 136 [EPA-HQ-OW-2010-0192; FRL-9504-2] Guidelines Establishing Test Procedures for the Analysis of Pollutants Under the Clean Water Act; Analysis and Sampling... waste constituent. Similarly, if EPA has established sampling requirements, measurements taken under an...

  19. Classical Item Analysis Using Latent Variable Modeling: A Note on a Direct Evaluation Procedure

    ERIC Educational Resources Information Center

    Raykov, Tenko; Marcoulides, George A.

    2011-01-01

    A directly applicable latent variable modeling procedure for classical item analysis is outlined. The method allows one to point and interval estimate item difficulty, item correlations, and item-total correlations for composites consisting of categorical items. The approach is readily employed in empirical research and as a by-product permits…

  20. Common factor analysis versus principal component analysis: choice for symptom cluster research.

    PubMed

    Kim, Hee-Ju

    2008-03-01

    The purpose of this paper is to examine differences between two factor analytical methods and their relevance for symptom cluster research: common factor analysis (CFA) versus principal component analysis (PCA). Literature was critically reviewed to elucidate the differences between CFA and PCA. A secondary analysis (N = 84) was utilized to show the actual result differences from the two methods. CFA analyzes only the reliable common variance of data, while PCA analyzes all the variance of data. An underlying hypothetical process or construct is involved in CFA but not in PCA. PCA tends to increase factor loadings especially in a study with a small number of variables and/or low estimated communality. Thus, PCA is not appropriate for examining the structure of data. If the study purpose is to explain correlations among variables and to examine the structure of the data (this is usual for most cases in symptom cluster research), CFA provides a more accurate result. If the purpose of a study is to summarize data with a smaller number of variables, PCA is the choice. PCA can also be used as an initial step in CFA because it provides information regarding the maximum number and nature of factors. In using factor analysis for symptom cluster research, several issues need to be considered, including subjectivity of solution, sample size, symptom selection, and level of measure.

  1. Post-procedure bleeding in interventional radiology.

    PubMed

    Mayer, J; Tacher, V; Novelli, L; Djabbari, M; You, K; Chiaradia, M; Deux, J-F; Kobeiter, H

    2015-01-01

    Following interventional radiology procedures, bleeding can occur in 0.5 to 4% of the cases. Risk factors are related to the patient, to the procedure, and to the end organ. Bleeding is treated usually by interventional radiologists and consists mainly of embolization. Bleeding complications are preventable: before the procedure by checking hemostasis, during the procedure by ensuring the accurate puncture site (with ultrasound or fluoroscopy guidance) or by treating the puncture path using gelatin sponge, curaspon(®), biological glue or thermocoagulation, and after the procedure by carefully monitoring the patients. Copyright © 2015 Éditions françaises de radiologie. Published by Elsevier Masson SAS. All rights reserved.

  2. Factors predictive of survival after stapler hepatectomy of hepatocellular carcinoma: a multivariate, single-center analysis.

    PubMed

    Hoffmann, Katrin; Müller-Bütow, Verena; Franz, Clemens; Hinz, Ulf; Longerich, Thomas; Büchler, Markus W; Schemmer, Peter

    2014-02-01

    New technical devices for hepatic parenchymal transection have improved perioperative safety and patient survival. The aim of the present study was to determine the oncological outcome after stapler hepatectomy in patients with HCC. Data of 95 patients who underwent stapler hepatectomy for HCC between 2001 and 2011 were analyzed retrospectively regarding clinical safety of the procedure and predictive factors for survial. Thirty-nine minor (≤2 segments) and 56 major (≥3 segments) hepatic resections were performed. The median survival was 47.5 months, after 36 months follow-up. Low grading, tumors ≥5 cm, multiple nodules and liver cirrhosis were predictors of decreased overall survival using multivariate analysis with hazard ratio(HR)=2.62, 2.41, 2.05, and 1.92 respectively. An estimated intra-operative blood loss of ≥1.2l was inversely correlated to disease free survival (HR=1.96). Stapler hepatectomy is a safe procedure in patients with HCC. Substantial intraoperative blood loss and the presence of cirrhosis independently predict the overall probability of patient survival. Intraoperative blood loss directly impacts HCC recurrence.

  3. Requirements for emergent neurosurgical procedures among patients undergoing neuroendovascular procedures in contemporary practice.

    PubMed

    Khatri, R; Ansar, M; Sultan, F; Chaudhry, S A; Khan, A A; Rodriguez, G J; Tummala, R P; Qureshi, A I

    2012-03-01

    Provisions for an emergent neurosurgical procedure have been a mandatory component of centers that perform neuroendovascular procedures. We sought to determine the need for emergent neurosurgical procedures following neuroendovascular interventions in 2 comprehensive stroke centers in settings with such provisions. Analysis of retrospectively collected data from procedure logs and patient charts was performed to identify patients who required immediate (before the termination of the intervention) or adjunctive (within 24 hours of the intervention) neurosurgical procedures related to a neuroendovascular intervention complication. The types of neurosurgical procedures and in-hospital outcomes of identified patients are reported as an aggregate and per endovascular procedure-type analyses. We reviewed a total of 933 neuroendovascular procedures performed during 3.5 years (2006-2010). A total of 759 intracranial procedures were performed. There was a need for emergent neurosurgical procedures in 8 patients (0.85% cumulative incidence and 1.05% for major intracranial procedures) (mean age, 46 years; 7 were women); the procedures were categorized as 3 immediate and 5 adjunctive procedures. There were 5 in-hospital deaths (62.5%) among these 8 patients. Neurosurgical procedures performed were external ventricular drainage placement in 6 (6 of 8, 75%) patients, decompressive craniectomy in 1 (12.5%) patient, and both surgical procedures in 1 (12.5%) patient. The need for emergent neurosurgical procedures is very low among patients undergoing intracranial neuroendovascular procedures. Survival in such patients despite emergent neurosurgical procedures is quite low.

  4. Derived Basic Ability Factors: A Factor Analysis Replication Study.

    ERIC Educational Resources Information Center

    Lee, Mickey, M.; Lee, Lynda Newby

    The purpose of this study was to replicate the study conducted by Potter, Sagraves, and McDonald to determine whether their recommended analysis could separate criterion variables into similar factors that were stable from year to year and from school to school. The replication samples consisted of all students attending Louisiana State University…

  5. Logistic regression analysis of risk factors for postoperative recurrence of spinal tumors and analysis of prognostic factors.

    PubMed

    Zhang, Shanyong; Yang, Lili; Peng, Chuangang; Wu, Minfei

    2018-02-01

    The aim of the present study was to investigate the risk factors for postoperative recurrence of spinal tumors by logistic regression analysis and analysis of prognostic factors. In total, 77 male and 48 female patients with spinal tumor were selected in our hospital from January, 2010 to December, 2015 and divided into the benign (n=76) and malignant groups (n=49). All the patients underwent microsurgical resection of spinal tumors and were reviewed regularly 3 months after operation. The McCormick grading system was used to evaluate the postoperative spinal cord function. Data were subjected to statistical analysis. Of the 125 cases, 63 cases showed improvement after operation, 50 cases were stable, and deterioration was found in 12 cases. The improvement rate of patients with cervical spine tumor, which reached 56.3%, was the highest. Fifty-two cases of sensory disturbance, 34 cases of pain, 30 cases of inability to exercise, 26 cases of ataxia, and 12 cases of sphincter disorders were found after operation. Seventy-two cases (57.6%) underwent total resection, 18 cases (14.4%) received subtotal resection, 23 cases (18.4%) received partial resection, and 12 cases (9.6%) were only treated with biopsy/decompression. Postoperative recurrence was found in 57 cases (45.6%). The mean recurrence time of patients in the malignant group was 27.49±6.09 months, and the mean recurrence time of patients in the benign group was 40.62±4.34. The results were significantly different (P<0.001). Recurrence was found in 18 cases of the benign group and 39 cases of the malignant group, and results were significantly different (P<0.001). Tumor recurrence was shorter in patients with a higher McCormick grade (P<0.001). Recurrence was found in 13 patients with resection and all the patients with partial resection or biopsy/decompression. The results were significantly different (P<0.001). Logistic regression analysis of total resection-related factors showed that total resection

  6. Logistic regression analysis of risk factors for postoperative recurrence of spinal tumors and analysis of prognostic factors

    PubMed Central

    Zhang, Shanyong; Yang, Lili; Peng, Chuangang; Wu, Minfei

    2018-01-01

    The aim of the present study was to investigate the risk factors for postoperative recurrence of spinal tumors by logistic regression analysis and analysis of prognostic factors. In total, 77 male and 48 female patients with spinal tumor were selected in our hospital from January, 2010 to December, 2015 and divided into the benign (n=76) and malignant groups (n=49). All the patients underwent microsurgical resection of spinal tumors and were reviewed regularly 3 months after operation. The McCormick grading system was used to evaluate the postoperative spinal cord function. Data were subjected to statistical analysis. Of the 125 cases, 63 cases showed improvement after operation, 50 cases were stable, and deterioration was found in 12 cases. The improvement rate of patients with cervical spine tumor, which reached 56.3%, was the highest. Fifty-two cases of sensory disturbance, 34 cases of pain, 30 cases of inability to exercise, 26 cases of ataxia, and 12 cases of sphincter disorders were found after operation. Seventy-two cases (57.6%) underwent total resection, 18 cases (14.4%) received subtotal resection, 23 cases (18.4%) received partial resection, and 12 cases (9.6%) were only treated with biopsy/decompression. Postoperative recurrence was found in 57 cases (45.6%). The mean recurrence time of patients in the malignant group was 27.49±6.09 months, and the mean recurrence time of patients in the benign group was 40.62±4.34. The results were significantly different (P<0.001). Recurrence was found in 18 cases of the benign group and 39 cases of the malignant group, and results were significantly different (P<0.001). Tumor recurrence was shorter in patients with a higher McCormick grade (P<0.001). Recurrence was found in 13 patients with resection and all the patients with partial resection or biopsy/decompression. The results were significantly different (P<0.001). Logistic regression analysis of total resection-related factors showed that total resection

  7. Risk factors of chronic periodontitis on healing response: a multilevel modelling analysis.

    PubMed

    Song, J; Zhao, H; Pan, C; Li, C; Liu, J; Pan, Y

    2017-09-15

    Chronic periodontitis is a multifactorial polygenetic disease with an increasing number of associated factors that have been identified over recent decades. Longitudinal epidemiologic studies have demonstrated that the risk factors were related to the progression of the disease. A traditional multivariate regression model was used to find risk factors associated with chronic periodontitis. However, the approach requirement of standard statistical procedures demands individual independence. Multilevel modelling (MLM) data analysis has widely been used in recent years, regarding thorough hierarchical structuring of the data, decomposing the error terms into different levels, and providing a new analytic method and framework for solving this problem. The purpose of our study is to investigate the relationship of clinical periodontal index and the risk factors in chronic periodontitis through MLM analysis and to identify high-risk individuals in the clinical setting. Fifty-four patients with moderate to severe periodontitis were included. They were treated by means of non-surgical periodontal therapy, and then made follow-up visits regularly at 3, 6, and 12 months after therapy. Each patient answered a questionnaire survey and underwent measurement of clinical periodontal parameters. Compared with baseline, probing depth (PD) and clinical attachment loss (CAL) improved significantly after non-surgical periodontal therapy with regular follow-up visits at 3, 6, and 12 months after therapy. The null model and variance component models with no independent variables included were initially obtained to investigate the variance of the PD and CAL reductions across all three levels, and they showed a statistically significant difference (P < 0.001), thus establishing that MLM data analysis was necessary. Site-level had effects on PD and CAL reduction; those variables could explain 77-78% of PD reduction and 70-80% of CAL reduction at 3, 6, and 12 months. Other levels only

  8. Procedural instruction in invasive bedside procedures: a systematic review and meta-analysis of effective teaching approaches.

    PubMed

    Huang, Grace C; McSparron, Jakob I; Balk, Ethan M; Richards, Jeremy B; Smith, C Christopher; Whelan, Julia S; Newman, Lori R; Smetana, Gerald W

    2016-04-01

    Optimal approaches to teaching bedside procedures are unknown. To identify effective instructional approaches in procedural training. We searched PubMed, EMBASE, Web of Science and Cochrane Library through December 2014. We included research articles that addressed procedural training among physicians or physician trainees for 12 bedside procedures. Two independent reviewers screened 9312 citations and identified 344 articles for full-text review. Two independent reviewers extracted data from full-text articles. We included measurements as classified by translational science outcomes T1 (testing settings), T2 (patient care practices) and T3 (patient/public health outcomes). Due to incomplete reporting, we post hoc classified study outcomes as 'negative' or 'positive' based on statistical significance. We performed meta-analyses of outcomes on the subset of studies sharing similar outcomes. We found 161 eligible studies (44 randomised controlled trials (RCTs), 34 non-RCTs and 83 uncontrolled trials). Simulation was the most frequently published educational mode (78%). Our post hoc classification showed that studies involving simulation, competency-based approaches and RCTs had higher frequencies of T2/T3 outcomes. Meta-analyses showed that simulation (risk ratio (RR) 1.54 vs 0.55 for studies with vs without simulation, p=0.013) and competency-based approaches (RR 3.17 vs 0.89, p<0.001) were effective forms of training. This systematic review of bedside procedural skills demonstrates that the current literature is heterogeneous and of varying quality and rigour. Evidence is strongest for the use of simulation and competency-based paradigms in teaching procedures, and these approaches should be the mainstay of programmes that train physicians to perform procedures. Further research should clarify differences among instructional methods (eg, forms of hands-on training) rather than among educational modes (eg, lecture vs simulation). Published by the BMJ Publishing

  9. Isolating the Effects of Training Using Simple Regression Analysis: An Example of the Procedure.

    ERIC Educational Resources Information Center

    Waugh, C. Keith

    This paper provides a case example of simple regression analysis, a forecasting procedure used to isolate the effects of training from an identified extraneous variable. This case example focuses on results of a three-day sales training program to improve bank loan officers' knowledge, skill-level, and attitude regarding solicitation and sale of…

  10. Risk factors for postoperative complications in robotic general surgery.

    PubMed

    Fantola, Giovanni; Brunaud, Laurent; Nguyen-Thi, Phi-Linh; Germain, Adeline; Ayav, Ahmet; Bresler, Laurent

    2017-03-01

    The feasibility and safety of robotically assisted procedures in general surgery have been reported from various groups worldwide. Because postoperative complications may lead to longer hospital stays and higher costs overall, analysis of risk factors for postoperative surgical complications in this subset of patients is clinically relevant. The goal of this study was to identify risk factors for postoperative morbidity after robotic surgical procedures in general surgery. We performed an observational monocentric retrospective study. All consecutive robotic surgical procedures from November 2001 to December 2013 were included. One thousand consecutive general surgery patients met the inclusion criteria. The mean overall postoperative morbidity and major postoperative morbidity (Clavien >III) rates were 20.4 and 6 %, respectively. This included a conversion rate of 4.4 %, reoperation rate of 4.5 %, and mortality rate of 0.2 %. Multivariate analysis showed that ASA score >3 [OR 1.7; 95 % CI (1.2-2.4)], hematocrit value <38 [OR 1.6; 95 % CI (1.1-2.2)], previous abdominal surgery [OR 1.5; 95 % CI (1-2)], advanced dissection [OR 5.8; 95 % CI (3.1-10.6)], and multiquadrant surgery [OR 2.5; 95 % CI (1.7-3.8)] remained independent risk factors for overall postoperative morbidity. It also showed that advanced dissection [OR 4.4; 95 % CI (1.9-9.6)] and multiquadrant surgery [OR 4.4; 95 % CI (2.3-8.5)] remained independent risk factors for major postoperative morbidity (Clavien >III). This study identifies independent risk factors for postoperative overall and major morbidity in robotic general surgery. Because these factors independently impacted postoperative complications, we believe they could be taken into account in future studies comparing conventional versus robot-assisted laparoscopic procedures in general surgery.

  11. On the Likelihood Ratio Test for the Number of Factors in Exploratory Factor Analysis

    ERIC Educational Resources Information Center

    Hayashi, Kentaro; Bentler, Peter M.; Yuan, Ke-Hai

    2007-01-01

    In the exploratory factor analysis, when the number of factors exceeds the true number of factors, the likelihood ratio test statistic no longer follows the chi-square distribution due to a problem of rank deficiency and nonidentifiability of model parameters. As a result, decisions regarding the number of factors may be incorrect. Several…

  12. Analysis of half diallel mating designs I: a practical analysis procedure for ANOVA approximation.

    Treesearch

    G.R. Johnson; J.N. King

    1998-01-01

    Procedures to analyze half-diallel mating designs using the SAS statistical package are presented. The procedure requires two runs of PROC and VARCOMP and results in estimates of additive and non-additive genetic variation. The procedures described can be modified to work on most statistical software packages which can compute variance component estimates. The...

  13. Bootstrap-based procedures for inference in nonparametric receiver-operating characteristic curve regression analysis.

    PubMed

    Rodríguez-Álvarez, María Xosé; Roca-Pardiñas, Javier; Cadarso-Suárez, Carmen; Tahoces, Pablo G

    2018-03-01

    Prior to using a diagnostic test in a routine clinical setting, the rigorous evaluation of its diagnostic accuracy is essential. The receiver-operating characteristic curve is the measure of accuracy most widely used for continuous diagnostic tests. However, the possible impact of extra information about the patient (or even the environment) on diagnostic accuracy also needs to be assessed. In this paper, we focus on an estimator for the covariate-specific receiver-operating characteristic curve based on direct regression modelling and nonparametric smoothing techniques. This approach defines the class of generalised additive models for the receiver-operating characteristic curve. The main aim of the paper is to offer new inferential procedures for testing the effect of covariates on the conditional receiver-operating characteristic curve within the above-mentioned class. Specifically, two different bootstrap-based tests are suggested to check (a) the possible effect of continuous covariates on the receiver-operating characteristic curve and (b) the presence of factor-by-curve interaction terms. The validity of the proposed bootstrap-based procedures is supported by simulations. To facilitate the application of these new procedures in practice, an R-package, known as npROCRegression, is provided and briefly described. Finally, data derived from a computer-aided diagnostic system for the automatic detection of tumour masses in breast cancer is analysed.

  14. NASTRAN/FLEXSTAB procedure for static aeroelastic analysis

    NASA Technical Reports Server (NTRS)

    Schuster, L. S.

    1984-01-01

    Presented is a procedure for using the FLEXSTAB External Structural Influence Coefficients (ESIC) computer program to produce the structural data necessary for the FLEXSTAB Stability Derivatives and Static Stability (SD&SS) program. The SD&SS program computes trim state, stability derivatives, and pressure and deflection data for a flexible airplane having a plane of symmetry. The procedure used a NASTRAN finite-element structural model as the source of structural data in the form of flexibility matrices. Selection of a set of degrees of freedom, definition of structural nodes and panels, reordering and reformatting of the flexibility matrix, and redistribution of existing point mass data are among the topics discussed. Also discussed are boundary conditions and the NASTRAN substructuring technique.

  15. 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)

  16. Adaptive kernel independent component analysis and UV spectrometry applied to characterize the procedure for processing prepared rhubarb roots.

    PubMed

    Wang, Guoqing; Hou, Zhenyu; Peng, Yang; Wang, Yanjun; Sun, Xiaoli; Sun, Yu-an

    2011-11-07

    By determination of the number of absorptive chemical components (ACCs) in mixtures using median absolute deviation (MAD) analysis and extraction of spectral profiles of ACCs using kernel independent component analysis (KICA), an adaptive KICA (AKICA) algorithm was proposed. The proposed AKICA algorithm was used to characterize the procedure for processing prepared rhubarb roots by resolution of the measured mixed raw UV spectra of the rhubarb samples that were collected at different steaming intervals. The results show that the spectral features of ACCs in the mixtures can be directly estimated without chemical and physical pre-separation and other prior information. The estimated three independent components (ICs) represent different chemical components in the mixtures, which are mainly polysaccharides (IC1), tannin (IC2), and anthraquinone glycosides (IC3). The variations of the relative concentrations of the ICs can account for the chemical and physical changes during the processing procedure: IC1 increases significantly before the first 5 h, and is nearly invariant after 6 h; IC2 has no significant changes or is slightly decreased during the processing procedure; IC3 decreases significantly before the first 5 h and decreases slightly after 6 h. The changes of IC1 can explain why the colour became black and darkened during the processing procedure, and the changes of IC3 can explain why the processing procedure can reduce the bitter and dry taste of the rhubarb roots. The endpoint of the processing procedure can be determined as 5-6 h, when the increasing or decreasing trends of the estimated ICs are insignificant. The AKICA-UV method provides an alternative approach for the characterization of the processing procedure of rhubarb roots preparation, and provides a novel way for determination of the endpoint of the traditional Chinese medicine (TCM) processing procedure by inspection of the change trends of the ICs.

  17. Rates and risk factors of unplanned 30-day readmission following general and thoracic pediatric surgical procedures.

    PubMed

    Polites, Stephanie F; Potter, Donald D; Glasgow, Amy E; Klinkner, Denise B; Moir, Christopher R; Ishitani, Michael B; Habermann, Elizabeth B

    2017-08-01

    Postoperative unplanned readmissions are costly and decrease patient satisfaction; however, little is known about this complication in pediatric surgery. The purpose of this study was to determine rates and predictors of unplanned readmission in a multi-institutional cohort of pediatric surgical patients. Unplanned 30-day readmissions following general and thoracic surgical procedures in children <18 were identified from the 2012-2014 National Surgical Quality Improvement Program- Pediatric. Time-dependent rates of readmission per 30 person-days were determined to account for varied postoperative length of stay (pLOS). Patients were randomly divided into 70% derivation and 30% validation cohorts which were used for creation and validation of a risk model for readmission. Readmission occurred in 1948 (3.6%) of 54,870 children for a rate of 4.3% per 30 person-days. Adjusted predictors of readmission included hepatobiliary procedures, increased wound class, operative duration, complications, and pLOS. The predictive model discriminated well in the derivation and validation cohorts (AUROC 0.710 and 0.701) with good calibration between observed and expected readmission events in both cohorts (p>.05). Unplanned readmission occurs less frequently in pediatric surgery than what is described in adults, calling into question its use as a quality indicator in this population. Factors that predict readmission including type of procedure, complications, and pLOS can be used to identify at-risk children and develop prevention strategies. III. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Patient Dose During Carotid Artery Stenting With Embolic-Protection Devices: Evaluation With Radiochromic Films and Related Diagnostic Reference Levels According to Factors Influencing the Procedure

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

    D'Ercole, Loredana, E-mail: l.dercole@smatteo.pv.it; Quaretti, Pietro; Cionfoli, Nicola

    2013-04-15

    To measure the maximum entrance skin dose (MESD) on patients undergoing carotid artery stenting (CAS) using embolic-protection devices, to analyze the dependence of dose and exposure parameters on anatomical, clinical, and technical factors affecting the procedure complexity, to obtain some local diagnostic reference levels (DRLs), and to evaluate whether overcoming DRLs is related to procedure complexity. MESD were evaluated with radiochromic films in 31 patients (mean age 72 {+-} 7 years). Five of 33 (15 %) procedures used proximal EPD, and 28 of 33 (85 %) procedures used distal EPD. Local DRLs were derived from the recorded exposure parameters inmore » 93 patients (65 men and 28 women, mean age 73 {+-} 9 years) undergoing 96 CAS with proximal (33 %) or distal (67 %) EPD. Four bilateral lesions were included. MESD values (mean 0.96 {+-} 0.42 Gy) were <2 Gy without relevant dependence on procedure complexity. Local DRL values for kerma area product (KAP), fluoroscopy time (FT), and number of frames (N{sub FR}) were 269 Gy cm{sup 2}, 28 minutes, and 251, respectively. Only simultaneous bilateral treatment was associated with KAP (odds ratio [OR] 10.14, 95 % confidence interval [CI] 1-102.7, p < 0.05) and N{sub FR} overexposures (OR 10.8, 95 % CI 1.1-109.5, p < 0.05). Type I aortic arch decreased the risk of FT overexposure (OR 0.4, 95 % CI 0.1-0.9, p = 0.042), and stenosis {>=} 90 % increased the risk of N{sub FR} overexposure (OR 2.8, 95 % CI 1.1-7.4, p = 0.040). At multivariable analysis, stenosis {>=} 90 % (OR 2.8, 95 % CI 1.1-7.4, p = 0.040) and bilateral treatment (OR 10.8, 95 % CI 1.1-109.5, p = 0.027) were associated with overexposure for two or more parameters. Skin doses are not problematic in CAS with EPD because these procedures rarely lead to doses >2 Gy.« less

  19. Hand function evaluation: a factor analysis study.

    PubMed

    Jarus, T; Poremba, R

    1993-05-01

    The purpose of this study was to investigate hand function evaluations. Factor analysis with varimax rotation was used to assess the fundamental characteristics of the items included in the Jebsen Hand Function Test and the Smith Hand Function Evaluation. The study sample consisted of 144 subjects without disabilities and 22 subjects with Colles fracture. Results suggest a four factor solution: Factor I--pinch movement; Factor II--grasp; Factor III--target accuracy; and Factor IV--activities of daily living. These categories differentiated the subjects without Colles fracture from the subjects with Colles fracture. A hand function evaluation consisting of these four factors would be useful. Such an evaluation that can be used for current clinical purposes is provided.

  20. Fundamental procedures of geographic information analysis

    NASA Technical Reports Server (NTRS)

    Berry, J. K.; Tomlin, C. D.

    1981-01-01

    Analytical procedures common to most computer-oriented geographic information systems are composed of fundamental map processing operations. A conceptual framework for such procedures is developed and basic operations common to a broad range of applications are described. Among the major classes of primitive operations identified are those associated with: reclassifying map categories as a function of the initial classification, the shape, the position, or the size of the spatial configuration associated with each category; overlaying maps on a point-by-point, a category-wide, or a map-wide basis; measuring distance; establishing visual or optimal path connectivity; and characterizing cartographic neighborhoods based on the thematic or spatial attributes of the data values within each neighborhood. By organizing such operations in a coherent manner, the basis for a generalized cartographic modeling structure can be developed which accommodates a variety of needs in a common, flexible and intuitive manner. The use of each is limited only by the general thematic and spatial nature of the data to which it is applied.

  1. Variations in hospitals costs for surgical procedures: inefficient care or sick patients?

    PubMed

    Gani, Faiz; Hundt, John; Daniel, Michael; Efron, Jonathan E; Makary, Martin A; Pawlik, Timothy M

    2017-01-01

    Reducing unwanted variations has been identified as an avenue for cost containment. We sought to characterize variations in hospital costs after major surgery and quantitate the variability attributable to the patient, procedure, and provider. A total of 22,559 patients undergoing major surgical procedure at a tertiary-care center between 2009 and 2013 were identified. Hierarchical linear regression analysis was performed to calculate risk-adjusted fixed, variable and total costs. The median cost of surgery was $23,845 (interquartile ranges, 13,353 to 43,083). Factors associated with increased costs included insurance status (Medicare vs private; coefficient: 14,934; 95% CI = 12,445.7 to 17,422.5, P < .001), preoperative comorbidity (Charlson Comorbidity Index = 1; coefficient: 10,793; 95% CI = 8,412.7 to 13,174.2; Charlson Comorbidity Index ≥2; coefficient: 24,468; 95% CI = 22,552.7 to 26,383.6; both P < .001) and the development of a postoperative complication (coefficient: 58,624.1; 95% CI = 56,683.6 to 60,564.7; P < .001). Eighty-six percent of total variability was explained by patient-related factors, whereas 8% of the total variation was attributed to surgeon practices and 6% due to factors at the level of surgical specialty. Although inpatient costs varied markedly between procedures and providers, the majority of variation in costs was due to patient-level factors and should be targeted by future cost containment strategies. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Evaluation of shoulder function in clavicular fracture patients after six surgical procedures based on a network meta-analysis.

    PubMed

    Huang, Shou-Guo; Chen, Bo; Lv, Dong; Zhang, Yong; Nie, Feng-Feng; Li, Wei; Lv, Yao; Zhao, Huan-Li; Liu, Hong-Mei

    2017-01-01

    Purpose Using a network meta-analysis approach, our study aims to develop a ranking of the six surgical procedures, that is, Plate, titanium elastic nail (TEN), tension band wire (TBW), hook plate (HP), reconstruction plate (RP) and Knowles pin, by comparing the post-surgery constant shoulder scores in patients with clavicular fracture (CF). Methods A comprehensive search of electronic scientific literature databases was performed to retrieve publications investigating surgical procedures in CF, with the stringent eligible criteria, and clinical experimental studies of high quality and relevance to our area of interest were selected for network meta-analysis. Statistical analyses were conducted using Stata 12.0. Results A total of 19 studies met our inclusion criteria were eventually enrolled into our network meta-analysis, representing 1164 patients who had undergone surgical procedures for CF (TEN group = 240; Plate group = 164; TBW group  =  180; RP group  =  168; HP group  =  245; Knowles pin group  =  167). The network meta-analysis results revealed that RP significantly improved constant shoulder score in patients with CF when compared with TEN, and the post-operative constant shoulder scores in patients with CF after Plate, TBW, HP, Knowles pin and TEN were similar with no statistically significant differences. The treatment relative ranking of predictive probabilities of constant shoulder scores in patients with CF after surgery revealed the surface under the cumulative ranking curves (SUCRA) value is the highest in RP. Conclusion The current network meta-analysis suggests that RP may be the optimum surgical treatment among six inventions for patients with CF, and it can improve the shoulder score of patients with CF. Implications for Rehabilitation RP improves shoulder joint function after surgical procedure. RP achieves stability with minimal complications after surgery. RP may be the optimum surgical treatment for

  3. An efficient solution procedure for the thermoelastic analysis of truss space structures

    NASA Technical Reports Server (NTRS)

    Givoli, D.; Rand, O.

    1992-01-01

    A solution procedure is proposed for the thermal and thermoelastic analysis of truss space structures in periodic motion. In this method, the spatial domain is first descretized using a consistent finite element formulation. Then the resulting semi-discrete equations in time are solved analytically by using Fourier decomposition. Geometrical symmetry is taken advantage of completely. An algorithm is presented for the calculation of heat flux distribution. The method is demonstrated via a numerical example of a cylindrically shaped space structure.

  4. Guidelines as rationing tools: a qualitative analysis of psychosocial patient selection criteria for cardiac procedures

    PubMed Central

    Giacomini, Mita K.; Cook, Deborah J.; Streiner, David L.; Anand, Sonia S.

    2001-01-01

    Background Cardiac procedure guidelines often include psychosocial criteria for selecting patients that potentially introduce social value judgements into clinical decisions and decisions about the rationing of care. The aim of this study was to investigate the terms and justifications for and the meanings of psychosocial patient characteristics used in cardiac procedure guidelines. Methods We selected English-language guidelines published since 1990 and chapters in textbooks published since 1989. These guidelines amalgamated multiple sources of evidence and expertise and made recommendations regarding patient selection for specific procedures. A multidisciplinary team of physicians and social scientists extracted passages regarding psychosocial criteria and developed categories and conceptual relationships to describe and interpret their content. Results Sixty-five papers met the criteria for inclusion in the study. Forty-five (69%) mentioned psychosocial criteria as procedure indications or contraindications. The latter fell into several categories, including behavioural and psychological issues, relationships with significant others, financial resources, social roles and environmental circumstances. Interpretation Psychosocial characteristics are portrayed as having 2 roles in patient selection: as risk factors intrinsic to the candidate or as indicators of need for special intervention. Guidelines typically simply list psychosocial contraindications without clarifying their specific nature or providing any justification for their use. Psychosocial considerations can help in the evaluation of patients for cardiac procedures, but they become ethically controversial when used to restrict access. The use of psychosocial indications and contraindications could be improved by more precise descriptions of the psychosocial problem at issue, explanations regarding why the criterion matters and justification of the characteristic using a biological rationale or research

  5. NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR ANALYSIS OF VOLATILE ORGANIC COMPOUNDS COLLECTED WITH A PASSIVE SAMPLER (BCO-L-17.1)

    EPA Science Inventory

    The purpose of this SOP is to describe the methodology used for the analysis of the 3M OVM 3500 Organic Vapor Monitors for volatile organic compounds (VOCs), using solvent extraction and standard gas chromatography/mass spectrometry (GC/MS) analysis procedures. This procedure was...

  6. Multivariate analysis of prognostic factors in synovial sarcoma.

    PubMed

    Koh, Kyoung Hwan; Cho, Eun Yoon; Kim, Dong Wook; Seo, Sung Wook

    2009-11-01

    Many studies have described the diversity of synovial sarcoma in terms of its biological characteristics and clinical features. Moreover, much effort has been expended on the identification of prognostic factors because of unpredictable behaviors of synovial sarcomas. However, with the exception of tumor size, published results have been inconsistent. We attempted to identify independent risk factors using survival analysis. Forty-one consecutive patients with synovial sarcoma were prospectively followed from January 1997 to March 2008. Overall and progression-free survival for age, sex, tumor size, tumor location, metastasis at presentation, histologic subtype, chemotherapy, radiation therapy, and resection margin were analyzed, and standard multivariate Cox proportional hazard regression analysis was used to evaluate potential prognostic factors. Tumor size (>5 cm), nonlimb-based tumors, metastasis at presentation, and a monophasic subtype were associated with poorer overall survival. Multivariate analysis showed metastasis at presentation and monophasic tumor subtype affected overall survival. For the progression-free survival, monophasic subtype was found to be only 1 prognostic factor. The study confirmed that histologic subtype is the single most important independent prognostic factors of synovial sarcoma regardless of tumor stage.

  7. Automated processing of first-pass radionuclide angiocardiography by factor analysis of dynamic structures.

    PubMed

    Cavailloles, F; Bazin, J P; Capderou, A; Valette, H; Herbert, J L; Di Paola, R

    1987-05-01

    A method for automatic processing of cardiac first-pass radionuclide study is presented. This technique, factor analysis of dynamic structures (FADS) provides an automatic separation of anatomical structures according to their different temporal behaviour, even if they are superimposed. FADS has been applied to 76 studies. A description of factor patterns obtained in various pathological categories is presented. FADS provides easy diagnosis of shunts and tricuspid insufficiency. Quantitative information derived from the factors (cardiac output and mean transit time) were compared to those obtained by the region of interest method. Using FADS, a higher correlation with cardiac catheterization was found for cardiac output calculation. Thus compared to the ROI method, FADS presents obvious advantages: a good separation of overlapping cardiac chambers is obtained; this operator independant method provides more objective and reproducible results. A number of parameters of the cardio-pulmonary function can be assessed by first-pass radionuclide angiocardiography (RNA) [1,2]. Usually, they are calculated using time-activity curves (TAC) from regions of interest (ROI) drawn on the cardiac chambers and the lungs. This method has two main drawbacks: (1) the lack of inter and intra-observers reproducibility; (2) the problem of crosstalk which affects the evaluation of the cardio-pulmonary performance. The crosstalk on planar imaging is due to anatomical superimposition of the cardiac chambers and lungs. The activity measured in any ROI is the sum of the activity in several organs and 'decontamination' of the TAC cannot easily be performed using the ROI method [3]. Factor analysis of dynamic structures (FADS) [4,5] can solve the two problems mentioned above. It provides an automatic separation of anatomical structures according to their different temporal behaviour, even if they are superimposed. The resulting factors are estimates of the time evolution of the activity in each

  8. Methods of analysis by the U.S. Geological Survey National Water Quality Laboratory; comparison of a nitric acid in-bottle digestion procedure to other whole-water digestion procedures

    USGS Publications Warehouse

    Garbarino, John R.; Hoffman, Gerald L.

    1999-01-01

    A hydrochloric acid in-bottle digestion procedure is used to partially digest wholewater samples prior to determining recoverable elements by various analytical methods. The use of hydrochloric acid is problematic for some methods of analysis because of spectral interference. The inbottle digestion procedure has been modified to eliminate such interference by using nitric acid instead of hydrochloric acid in the digestion. Implications of this modification are evaluated by comparing results for a series of synthetic whole-water samples. Results are also compared with those obtained by using U.S. Environmental Protection Agency (1994) (USEPA) Method 200.2 total-recoverable digestion procedure. Percentage yields that use the nitric acid inbottle digestion procedure are within 10 percent of the hydrochloric acid in-bottle yields for 25 of the 26 elements determined in two of the three synthetic whole-water samples tested. Differences in percentage yields for the third synthetic whole-water sample were greater than 10 percent for 16 of the 26 elements determined. The USEPA method was the most rigorous for solubilizing elements from particulate matter in all three synthetic whole-water samples. Nevertheless, the variability in the percentage yield by using the USEPA digestion procedure was generally greater than the in-bottle digestion procedure, presumably because of the difficulty in controlling the digestion conditions accurately.

  9. Procedural learning in Parkinson's disease, specific language impairment, dyslexia, schizophrenia, developmental coordination disorder, and autism spectrum disorders: A second-order meta-analysis.

    PubMed

    Clark, Gillian M; Lum, Jarrad A G

    2017-10-01

    The serial reaction time task (SRTT) has been used to study procedural learning in clinical populations. In this report, second-order meta-analysis was used to investigate whether disorder type moderates performance on the SRTT. Using this approach to quantitatively summarise past research, it was tested whether autism spectrum disorder, developmental coordination disorder, dyslexia, Parkinson's disease, schizophrenia, and specific language impairment differentially affect procedural learning on the SRTT. The main analysis revealed disorder type moderated SRTT performance (p=0.010). This report demonstrates comparable levels of procedural learning impairment in developmental coordination disorder, dyslexia, Parkinson's disease, schizophrenia, and specific language impairment. However, in autism, procedural learning is spared. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Conditional Versus Unconditional Procedures for Sample-Free Item Analysis

    ERIC Educational Resources Information Center

    Wright, Benjamin D.; Douglas, Graham A.

    1977-01-01

    Procedures for the Rasch model, sample free item calibration are reviewed and compared for accuracy. The theoretically ideal procedure is shown to have practical limitations. Two alternatives to the ideal are presented and discussed. A correction for bias in the most widely used alternative is presented. (Author/JKS)

  11. Cleaning procedure for improved photothermal background of toroidal optical microresonators

    NASA Astrophysics Data System (ADS)

    Horak, Erik H.; Knapper, Kassandra A.; Heylman, Kevin D.; Goldsmith, Randall H.

    2016-09-01

    High Q-factors and small mode volumes have made toroidal optical microresonators exquisite sensors to small shifts in the effective refractive index of the WGM modes. Eliminating contaminants and improving quality factors is key for many different sensing techniques, and is particularly important for photothermal imaging as contaminants add photothermal background obscuring objects of interest. Several different cleaning procedures including wet- and dry-chemical procedures are tested for their effect on Q-factors and photothermal background. RCA cleaning was shown to be successful in contrast to previously described acid cleaning procedures, most likely due to the different surface reactivity of the acid reagents used. UV-ozone cleaning was shown to be vastly superior to O2 plasma cleaning procedures, significantly reducing the photothermal background of the resonator.

  12. Factor Analysis for Clustered Observations.

    ERIC Educational Resources Information Center

    Longford, N. T.; Muthen, B. O.

    1992-01-01

    A two-level model for factor analysis is defined, and formulas for a scoring algorithm for this model are derived. A simple noniterative method based on decomposition of total sums of the squares and cross-products is discussed and illustrated with simulated data and data from the Second International Mathematics Study. (SLD)

  13. Completely automated modal analysis procedure based on the combination of different OMA methods

    NASA Astrophysics Data System (ADS)

    Ripamonti, Francesco; Bussini, Alberto; Resta, Ferruccio

    2018-03-01

    In this work a completely automated output-only Modal Analysis procedure is presented and all its benefits are listed. Based on the merging of different Operational Modal Analysis methods and a statistical approach, the identification process has been improved becoming more robust and giving as results only the real natural frequencies, damping ratios and mode shapes of the system. The effect of the temperature can be taken into account as well, leading to the creation of a better tool for automated Structural Health Monitoring. The algorithm has been developed and tested on a numerical model of a scaled three-story steel building present in the laboratories of Politecnico di Milano.

  14. ANALYSIS OF TRACE-LEVEL ORGANIC COMBUSTION PROCESS EMISSIONS USING NOVEL MULTIDIMENSIONAL GAS CHROMATOGRAPHY-MASS SPECTROMETRY PROCEDURES

    EPA Science Inventory

    The paper discusses the analysis of trace-level organic combustion process emissions using novel multidimensional gas chromatography-mass spectrometry (MDGC-MS) procedures. It outlines the application of the technique through the analyses of various incinerator effluent and produ...

  15. Purification and Properties of Streptococcal Competence Factor Isolated from Chemically Defined Medium

    PubMed Central

    Leonard, C. Gomez; Cole, Roger M.

    1972-01-01

    A procedure for the isolation and purification of competence factor produced in a defined medium by group H streptococci, strain Challis-6, is presented. Partial characterization and chemical analysis of the product are described. The procedure yields competence factor of high purity, as shown by homogeneity in electrofocusing, by electrophoresis in sodium dodecyl sulfate polyacrylamide gels, and by chemical analysis. The data indicate that competence factor is a small, dialyzable, highly basic compound. It is free from lipids, phosphorus, and carbohydrates, and is colorless and thermoresistant. Its biological activity is destroyed by trypsin but not by deoxyribonuclease, ribonuclease, lipase, or lysozyme. Its high isoelectric point of above pH 11.0 suggests that competence factor may be a protamine or a polymer of basic amino acids. The possibility that a polyamine may be an integral part of the polypeptide molecule has not been excluded. PMID:5018023

  16. Evaluation of Diabetes Mellitus as a Risk Factor for Major Complications in Patients Undergoing Aesthetic Surgery.

    PubMed

    Bamba, Ravinder; Gupta, Varun; Shack, R Bruce; Grotting, James C; Higdon, K Kye

    2016-05-01

    Diabetes mellitus has been linked with a variety of perioperative adverse events across surgical disciplines. There is a paucity of studies systematically examining risk factors, including diabetes, and complications of aesthetic surgical procedures. The purpose of this study was to compare incidence and type of complications between diabetic and non-diabetic patients undergoing various aesthetic surgical procedures, to identify specific procedures where diabetes significantly increases risk of complications, and to study diabetes as an independent risk factor for major complications following aesthetic surgery. A prospective cohort of 129,007 patients who enrolled into the CosmetAssure insurance program and underwent cosmetic surgical procedures between May 2008 and May 2013 were reviewed. Diabetes was evaluated as risk factor for major complications, requiring hospital admission, emergency room visit, or a reoperation within 30 days after surgery. Multivariate regression analysis was performed controlling for the effects of age, smoking, obesity, gender, type of procedures, and surgical facility. Overall, 2506 patients (1.9%) had a major complication. Diabetics had significantly more complications compared to non-diabetics (3.1% vs 1.9%, P < 0.01). In univariate analysis, infectious (1.1% vs 0.5%, P < 0.01) and pulmonary (0.3% vs 0.1%, P < 0.01) complications were significantly higher among diabetics. Notably, diabetics had higher risks of complication in body cases (4.3% vs 2.6%, P < 0.01) and specifically abdominoplasty (6.1% vs 3.0%, P < 0.01). In multivariate analysis, diabetes was found to be an independent risk factor of any complication (relative risk 1.31, P = 0.03) and infection (relative risk 1.70, P < 0.01). Diabetes is an independent risk factor of major complications, particularly infection, after aesthetic surgical procedures. © 2016 The American Society for Aesthetic Plastic Surgery, Inc. Reprints and permission: journals.permissions@oup.com.

  17. Evaluation of solution procedures for material and/or geometrically nonlinear structural analysis by the direct stiffness method.

    NASA Technical Reports Server (NTRS)

    Stricklin, J. A.; Haisler, W. E.; Von Riesemann, W. A.

    1972-01-01

    This paper presents an assessment of the solution procedures available for the analysis of inelastic and/or large deflection structural behavior. A literature survey is given which summarized the contribution of other researchers in the analysis of structural problems exhibiting material nonlinearities and combined geometric-material nonlinearities. Attention is focused at evaluating the available computation and solution techniques. Each of the solution techniques is developed from a common equation of equilibrium in terms of pseudo forces. The solution procedures are applied to circular plates and shells of revolution in an attempt to compare and evaluate each with respect to computational accuracy, economy, and efficiency. Based on the numerical studies, observations and comments are made with regard to the accuracy and economy of each solution technique.

  18. An Examination of the Test Scores of the Folger and Konovsky Measure of Procedural Justice.

    ERIC Educational Resources Information Center

    DeConinck, James B.; King, Wesley C., Jr.

    2002-01-01

    Examined the validity of the measure of procedural justice developed by R. Folger and M. Konovsky (1989) through confirmatory factor analysis of data from 416 bank employees and 221 marketing managers. Results indicate that an underlying construct for the feedback and planning subscales is the communication relationship between manager and…

  19. 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…

  20. Factors Associated with Anxiety About Colonoscopy: The Preparation, the Procedure, and the Anticipated Findings.

    PubMed

    Shafer, L A; Walker, J R; Waldman, C; Yang, C; Michaud, V; Bernstein, C N; Hathout, L; Park, J; Sisler, J; Restall, G; Wittmeier, K; Singh, H

    2018-03-01

    Previous research has assessed anxiety around colonoscopy procedures, but has not considered anxiety related to different aspects related to the colonoscopy process. Before colonoscopy, we assessed anxiety about: bowel preparation, the procedure, and the anticipated results. We evaluated associations between patient characteristics and anxiety in each area. An anonymous survey was distributed to patients immediately prior to their outpatient colonoscopy in six hospitals and two ambulatory care centers in Winnipeg, Canada. Anxiety was assessed using a visual analog scale. For each aspect, logistic regression models were used to explore associations between patient characteristics and high anxiety. A total of 1316 respondents completed the questions about anxiety (52% female, median age 56 years). Anxiety scores > 70 (high anxiety) were reported by 18% about bowel preparation, 29% about the procedure, and 28% about the procedure results. High anxiety about bowel preparation was associated with female sex, perceived unclear instructions, unfinished laxative, and no previous colonoscopies. High anxiety about the procedure was associated with female sex, no previous colonoscopies, and confusing instructions. High anxiety about the results was associated with symptoms as an indication for colonoscopy and instructions perceived as confusing. Fewer people had high anxiety about preparation than about the procedure and findings of the procedure. There are unique predictors of anxiety about each colonoscopy aspect. Understanding the nuanced differences in aspects of anxiety may help to design strategies to reduce anxiety, leading to improved acceptance of the procedure, compliance with preparation instructions, and less discomfort with the procedure.

  1. Interactions between toxic chemicals and natural environmental factors--a meta-analysis and case studies.

    PubMed

    Laskowski, Ryszard; Bednarska, Agnieszka J; Kramarz, Paulina E; Loureiro, Susana; Scheil, Volker; Kudłek, Joanna; Holmstrup, Martin

    2010-08-15

    The paper addresses problems arising from effects of natural environmental factors on toxicity of pollutants to organisms. Most studies on interactions between toxicants and natural factors, including those completed in the EU project NoMiracle (Novel Methods for Integrated Risk Assessment of Cumulative Stressors in Europe) described herein, showed that effects of toxic chemicals on organisms can differ vastly depending purely on external conditions. We compiled data from 61 studies on effects of temperature, moisture and dissolved oxygen on toxicity of a range of chemicals representing pesticides, polycyclic aromatic hydrocarbons, plant protection products of bacterial origin and trace metals. In 62.3% cases significant interactions (p< or =0.05 or less) between natural factors and chemicals were found, reaching 100% for the effect of dissolved oxygen on toxicity of waterborne chemicals. The meta-analysis of the 61 studies showed that the null hypothesis assuming no interactions between toxic chemicals and natural environmental factors should be rejected at p=2.7 x 10(-82) (truncated product method probability). In a few cases of more complex experimental designs, also second-order interactions were found, indicating that natural factors can modify interactions among chemicals. Such data emphasize the necessity of including information on natural factors and their variation in time and across geographic regions in ecological risk assessment. This can be done only if appropriate ecotoxicological test designs are used, in which test organisms are exposed to toxicants at a range of environmental conditions. We advocate designing such tests for the second-tier ecological risk assessment procedures. Copyright 2010 Elsevier B.V. All rights reserved.

  2. Comparison of procedures for correction of matrix interferences in the analysis of soils by ICP-OES with CCD detection

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

    Sadler, D.A.; Sun, F.; Littlejohn, D.

    1995-12-31

    ICP-OES is a useful technique for multi-element analysis of soils. However, as a number of elements are present in relatively high concentrations, matrix interferences can occur and examples have been widely reported. The availability of CCD detectors has increased the opportunities for rapid multi-element, multi-wave-length determination of elemental concentrations in soils and other environmental samples. As the composition of soils from industrial sites can vary considerably, especially when taken from different pit horizons, procedures are required to assess the extent of interferences and correct the effects, on a simultaneous multi-element basis. In single element analysis, plasma operating conditions can sometimesmore » be varied to minimize or even remove multiplicative interferences. In simultaneous multi-element analysis, the scope for this approach may be limited, depending on the spectrochemical characteristics of the emitting analyte species. Matrix matching, by addition of major sample components to the analyte calibrant solutions, can be used to minimize inaccuracies. However, there are also limitations to this procedure, when the sample composition varies significantly. Multiplicative interference effects can also be assessed by a {open_quotes}single standard addition{close_quotes} of each analyte to the sample solution and the information obtained may be used to correct the analyte concentrations determined directly. Each of these approaches has been evaluated to ascertain the best procedure for multi-element analysis of industrial soils by ICP-OES with CCD detection at multiple wavelengths. Standard reference materials and field samples have been analyzed to illustrate the efficacy of each procedure.« less

  3. Role of laser irradiation in direct pulp capping procedures: a systematic review and meta-analysis.

    PubMed

    Javed, Fawad; Kellesarian, Sergio Varela; Abduljabbar, Tariq; Gholamiazizi, Elham; Feng, Changyong; Aldosary, Khaled; Vohra, Fahim; Romanos, Georgios E

    2017-02-01

    A variety of materials are available to treat exposed dental pulp by direct pulp capping. The healing response of the pulp is crucial to form a dentin bridge and seal off the exposed pulp. Studies have used lasers to stimulate the exposed pulp to form tertiary dentin. The aim of the present systematic review and meta-analysis was to evaluate the evidence on the effects of laser irradiation as an adjunctive therapy to stimulate healing after pulp exposure. A systematic literature search was conducted up to April 2016. A structured search using the keywords "Direct pulp capping," "Lasers," "Calcium hydroxide pulp capping," and "Resin pulp capping" was performed. Initially, 34 potentially relevant articles were identified. After removal of duplicates and screening by title, abstract, and full text when necessary, nine studies were included. Studies were assessed for bias and data were synthetized using a random-effects meta-analysis model. Six studies were clinical, and three were preclinical animal trials; the follow-up period ranged from 2 weeks to 54 months. More than two thirds of the included studies showed that laser therapy used as an adjunct for direct pulp capping was more effective in maintaining pulp vitality than conventional therapy alone. Meta-analysis showed that the success rate in the laser treatment group was significantly higher than the control group (log odds ratio = 1.737; 95 % confidence interval, 1.304-2.171). Lasers treatment of exposed pulps can improve the outcome of direct pulp capping procedures; a number of confounding factors may have influenced the outcomes of the included studies.

  4. Clinical Outcomes of Root Reimplantation and Bentall Procedure: Propensity Score Matching Analysis.

    PubMed

    Lee, Heemoon; Cho, Yang Hyun; Sung, Kiick; Kim, Wook Sung; Park, Kay-Hyun; Jeong, Dong Seop; Park, Pyo Won; Lee, Young Tak

    2018-03-26

    This study aimed to evaluate the clinical outcomes of aortic root replacement(ARR) surgery:Root reimplantation as valve-sparing root replacement(VSR) and the Bentall procedure. We retrospectively reviewed 216 patients who underwent ARR between 1995 and 2013 at Samsung Medical Center. Patients were divided into two groups, depending on the procedure they underwent: Bentall(n=134) and VSR(n=82). The mean follow-up duration was 100.9±56.4 months. There were 2 early deaths in the Bentall group and none in the VSR group(p=0.53). Early morbidities were not different between the groups. Overall mortality was significantly lower in the VSR group (HR=0.12,p=0.04). Despite the higher reoperation rate in the VSR group(p=0.03), major adverse valve-related events(MAVRE) did not differ between the groups(p=0.28). Bleeding events were significantly higher in the Bentall group during follow-up(10 in Bentall group, 0 in VSR group, p=0.04). here were 6 thromboembolic events only in the Bentall group(p=0.11). We performed a propensity score matching analysis comparing the groups(134 Bentall vs 43 VSR). Matched analysis gave similar results, i.e. HR=0.17 and p=0.10 for overall mortality and HR=1.01 and p=0.99 for MAVRE. Although there was marginal significance in the propensity matched analysis, it is plausible to anticipate a survival benefit with VSR during long-term follow-up. Despite a higher reoperation for aortic valves, VSR can be a viable option in patients who decline life-long anticoagulation, especially the young or the patients in whom anticoagulation is contraindicated. Copyright © 2018. Published by Elsevier Inc.

  5. Progression of Human Factors Considerations for the In-Trail Procedure

    DOT National Transportation Integrated Search

    2016-03-16

    The In-Trail Procedure (ITP) is one of the Automatic Dependent Surveillance-Broadcast (ADS-B) applications in the NextGen program. The Federal Aviation Administration, in partnership with United Airlines, is conducting an operational evaluation of th...

  6. Simple estimation procedures for regression analysis of interval-censored failure time data under the proportional hazards model.

    PubMed

    Sun, Jianguo; Feng, Yanqin; Zhao, Hui

    2015-01-01

    Interval-censored failure time data occur in many fields including epidemiological and medical studies as well as financial and sociological studies, and many authors have investigated their analysis (Sun, The statistical analysis of interval-censored failure time data, 2006; Zhang, Stat Modeling 9:321-343, 2009). In particular, a number of procedures have been developed for regression analysis of interval-censored data arising from the proportional hazards model (Finkelstein, Biometrics 42:845-854, 1986; Huang, Ann Stat 24:540-568, 1996; Pan, Biometrics 56:199-203, 2000). For most of these procedures, however, one drawback is that they involve estimation of both regression parameters and baseline cumulative hazard function. In this paper, we propose two simple estimation approaches that do not need estimation of the baseline cumulative hazard function. The asymptotic properties of the resulting estimates are given, and an extensive simulation study is conducted and indicates that they work well for practical situations.

  7. The Recoverability of P-Technique Factor Analysis

    ERIC Educational Resources Information Center

    Molenaar, Peter C. M.; Nesselroade, John R.

    2009-01-01

    It seems that just when we are about to lay P-technique factor analysis finally to rest as obsolete because of newer, more sophisticated multivariate time-series models using latent variables--dynamic factor models--it rears its head to inform us that an obituary may be premature. We present the results of some simulations demonstrating that even…

  8. Limiting excessive postoperative blood transfusion after cardiac procedures. A review.

    PubMed Central

    Ferraris, V A; Ferraris, S P

    1995-01-01

    Analysis of blood product use after cardiac operations reveals that a few patients (< or = 20%) consume the majority of blood products (> 80%). The risk factors that predispose a minority of patients to excessive blood use include patient-related factors, transfusion practices, drug-related causes, and procedure-related factors. Multivariate studies suggest that patient age and red blood cell volume are independent patient-related variables that predict excessive blood product transfusion after cardiac procedures. Other factors include preoperative aspirin ingestion, type of operation, over- or underutilization of heparin during cardiopulmonary bypass, failure to correct hypothermia after cardiopulmonary bypass, and physician overtransfusion. A survey of the currently available blood conservation techniques reveals 5 that stand out as reliable methods: 1) high-dose aprotinin therapy, 2) preoperative erythropoietin therapy when time permits adequate dosage before operation, 3) hemodilution by harvest of whole blood immediately before cardiopulmonary bypass, 4) autologous predonation of blood, and 5) salvage of oxygenator blood after cardiopulmonary bypass. Other methods, such as the use of epsilon-aminocaproic acid or desmopressin, cell saving devices, reinfusion of shed mediastinal blood, and hemofiltration have been reported to be less reliable and may even be harmful in some high-risk patients. Consideration of the available data allows formulation of a 4-pronged plan for limiting excessive blood transfusion after surgery: 1) recognize the causes of excessive transfusion, including the importance of red blood cell volume, type of procedure being performed, preoperative aspirin ingestion, etc.; 2) establish a quality management program, including a survey of transfusion practices that emphasizes physician education and availability of real-time laboratory testing to guide transfusion therapy; 3) adopt a multimodal approach using institution-proven techniques; and

  9. Surgeon and type of anesthesia predict variability in surgical procedure times.

    PubMed

    Strum, D P; Sampson, A R; May, J H; Vargas, L G

    2000-05-01

    Variability in surgical procedure times increases the cost of healthcare delivery by increasing both the underutilization and overutilization of expensive surgical resources. To reduce variability in surgical procedure times, we must identify and study its sources. Our data set consisted of all surgeries performed over a 7-yr period at a large teaching hospital, resulting in 46,322 surgical cases. To study factors associated with variability in surgical procedure times, data mining techniques were used to segment and focus the data so that the analyses would be both technically and intellectually feasible. The data were subdivided into 40 representative segments of manageable size and variability based on headers adopted from the common procedural terminology classification. Each data segment was then analyzed using a main-effects linear model to identify and quantify specific sources of variability in surgical procedure times. The single most important source of variability in surgical procedure times was surgeon effect. Type of anesthesia, age, gender, and American Society of Anesthesiologists risk class were additional sources of variability. Intrinsic case-specific variability, unexplained by any of the preceding factors, was found to be highest for shorter surgeries relative to longer procedures. Variability in procedure times among surgeons was a multiplicative function (proportionate to time) of surgical time and total procedure time, such that as procedure times increased, variability in surgeons' surgical time increased proportionately. Surgeon-specific variability should be considered when building scheduling heuristics for longer surgeries. Results concerning variability in surgical procedure times due to factors such as type of anesthesia, age, gender, and American Society of Anesthesiologists risk class may be extrapolated to scheduling in other institutions, although specifics on individual surgeons may not. This research identifies factors associated

  10. Microbial ecology laboratory procedures manual NASA/MSFC

    NASA Technical Reports Server (NTRS)

    Huff, Timothy L.

    1990-01-01

    An essential part of the efficient operation of any microbiology laboratory involved in sample analysis is a standard procedures manual. The purpose of this manual is to provide concise and well defined instructions on routine technical procedures involving sample analysis and methods for monitoring and maintaining quality control within the laboratory. Of equal importance is the safe operation of the laboratory. This manual outlines detailed procedures to be followed in the microbial ecology laboratory to assure safety, analytical control, and validity of results.

  11. Faying Surface Lubrication Effects on Nut Factors

    NASA Technical Reports Server (NTRS)

    Taylor, Deneen M.; Morrison, Raymond F.

    2006-01-01

    Bolted joint analysis typically is performed using nut factors derived from textbooks and procedures from program requirement documents. Joint specific testing was performed for a critical International Space Station (ISS) joint. Test results indicate that for some configurations the nut factor may be significantly different than accepted textbook values. This paper presents results of joint specific testing to aid in determining if joint specific testing should be performed to insure required preloads are obtained.

  12. Evaluation of results of US corn and soybeans exploratory experiment: Classification procedures verification test. [Missouri, Iowa, Indiana, and Illinois

    NASA Technical Reports Server (NTRS)

    Carnes, J. G.; Baird, J. E. (Principal Investigator)

    1980-01-01

    The classification procedure utilized in making crop proportion estimates for corn and soybeans using remotely sensed data was evaluated. The procedure was derived during the transition year of the Large Area Crop Inventory Experiment. Analysis of variance techniques were applied to classifications performed by 3 groups of analysts who processed 25 segments selected from 4 agrophysical units (APU's). Group and APU effects were assessed to determine factors which affected the quality of the classifications. The classification results were studied to determine the effectiveness of the procedure in producing corn and soybeans proportion estimates.

  13. 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…

  14. Donor retention in health care in Iran: a factor analysis

    PubMed Central

    Aghababa, Sara; Nasiripour, Amir Ashkan; Maleki, Mohammadreza; Gohari, Mahmoodreza

    2017-01-01

    Background: Long-term financial support is essential for the survival of a charitable organization. Health charities need to identify the effective factors influencing donor retention. Methods: In the present study, the items of a questionnaire were derived from both literature review and semi-structured interviews related to donor retention. Using a purposive sampling, 300 academic and executive practitioners were selected. After the follow- up, a total of 243 usable questionnaires were prepared for factor analysis. The questionnaire was validated based on the face and content validity and reliability through Cronbach’s α-coefficient. Results: The results of exploratory factor analysis extracted 2 factors for retention: donor factor (variance = 33.841%; Cronbach’s α-coefficient = 90.2) and charity factor (variance = 29.038%; Cronbach’s α-coefficient = 82.8), respectively. Subsequently, confirmatory factor analysis was applied to support the overall reasonable fit. Conclusions: In this study, it was found that repeated monetary donations are supplied to the charitable organizations when both aspects of donor factor (retention factor and charity factor) for retention are taken into consideration. This model could provide a perspective for making sustainable donations and charitable giving PMID:28955663

  15. Investigation of the factor structure of the Wechsler Adult Intelligence Scale--Fourth Edition (WAIS-IV): exploratory and higher order factor analyses.

    PubMed

    Canivez, Gary L; Watkins, Marley W

    2010-12-01

    The present study examined the factor structure of the Wechsler Adult Intelligence Scale--Fourth Edition (WAIS-IV; D. Wechsler, 2008a) standardization sample using exploratory factor analysis, multiple factor extraction criteria, and higher order exploratory factor analysis (J. Schmid & J. M. Leiman, 1957) not included in the WAIS-IV Technical and Interpretation Manual (D. Wechsler, 2008b). Results indicated that the WAIS-IV subtests were properly associated with the theoretically proposed first-order factors, but all but one factor-extraction criterion recommended extraction of one or two factors. Hierarchical exploratory analyses with the Schmid and Leiman procedure found that the second-order g factor accounted for large portions of total and common variance, whereas the four first-order factors accounted for small portions of total and common variance. It was concluded that the WAIS-IV provides strong measurement of general intelligence, and clinical interpretation should be primarily at that level.

  16. Effect of Previous Abdominal Surgery on Laparoscopic Liver Resection: Analysis of Feasibility and Risk Factors for Conversion.

    PubMed

    Cipriani, Federica; Ratti, Francesca; Fiorentini, Guido; Catena, Marco; Paganelli, Michele; Aldrighetti, Luca

    2018-03-28

    Previous abdominal surgery has traditionally been considered an additional element of difficulty to later laparoscopic procedures. The aim of the study is to analyze the effect of previous surgery on the feasibility and safety of laparoscopic liver resection (LLR), and its role as a risk factor for conversion. After matching, 349 LLR in patients known for previous abdominal surgery (PS group) were compared with 349 LLR on patients with a virgin abdomen (NPS group). Subgroup analysis included 161 patients with previous upper abdominal surgery (UPS subgroup). Feasibility and safety were evaluated in terms of conversion rate, reasons for conversion and outcomes, and risk factors for conversion assessed via uni/multivariable analysis. Conversion rate was 9.4%, and higher for PS patients compared with NPS patients (13.7% versus 5.1%, P = .021). Difficult adhesiolysis resulted the commonest reason for conversion in PS group (5.7%). However, operative time (P = .840), blood loss (P = .270), transfusion (P = .650), morbidity rate (P = .578), hospital stay (P = .780), and R1 rate (P = .130) were comparable between PS and NPS group. Subgroup analysis confirmed higher conversion rates for UPS patients (23%) compared with both NPS (P = .015) and PS patients (P = .041). Previous surgery emerged as independent risk factor for conversion (P = .033), alongside the postero-superior location and major hepatectomy. LLR are feasible in case of previous surgery and proved to be safe and maintain the benefits of LLR carried out in standard settings. However, a history of surgery should be considered a risk factor for conversion.

  17. The Factor Structure of the English Language Development Assessment: A Confirmatory Factor Analysis

    ERIC Educational Resources Information Center

    Kuriakose, Anju

    2011-01-01

    This study investigated the internal factor structure of the English language development Assessment (ELDA) using confirmatory factor analysis. ELDA is an English language proficiency test developed by a consortium of multiple states and is used to identify and reclassify English language learners in kindergarten to grade 12. Scores on item…

  18. Influential Observations in Principal Factor Analysis.

    ERIC Educational Resources Information Center

    Tanaka, Yutaka; Odaka, Yoshimasa

    1989-01-01

    A method is proposed for detecting influential observations in iterative principal factor analysis. Theoretical influence functions are derived for two components of the common variance decomposition. The major mathematical tool is the influence function derived by Tanaka (1988). (SLD)

  19. Pilot Task Profiles, Human Factors, And Image Realism

    NASA Astrophysics Data System (ADS)

    McCormick, Dennis

    1982-06-01

    Computer Image Generation (CIG) visual systems provide real time scenes for state-of-the-art flight training simulators. The visual system reauires a greater understanding of training tasks, human factors, and the concept of image realism to produce an effective and efficient training scene than is required by other types of visual systems. Image realism must be defined in terms of pilot visual information reauirements. Human factors analysis of training and perception is necessary to determine the pilot's information requirements. System analysis then determines how the CIG and display device can best provide essential information to the pilot. This analysis procedure ensures optimum training effectiveness and system performance.

  20. When procedures meet practice in community pharmacies: qualitative insights from pharmacists and pharmacy support staff

    PubMed Central

    Ashcroft, Darren M

    2016-01-01

    Objectives Our aim was to explore how members of community pharmacy staff perceive and experience the role of procedures within the workplace in community pharmacies. Setting Community pharmacies in England and Wales. Participants 24 community pharmacy staff including pharmacists and pharmacy support staff were interviewed regarding their view of procedures in community pharmacy. Transcripts were analysed using thematic analysis. Results 3 main themes were identified. According to the ‘dissemination and creation of standard operating procedures’ theme, community pharmacy staff were required to follow a large amount of procedures as part of their work. At times, complying with all procedures was not possible. According to the ‘complying with procedures’ theme, there are several factors that influenced compliance with procedures, including work demands, the high workload and the social norm within the pharmacy. Lack of staff, pressure to hit targets and poor communication also affected how able staff felt to follow procedures. The third theme ‘procedural compliance versus using professional judgement’ highlighted tensions between the standardisation of practice and the professional autonomy of pharmacists. Pharmacists feared being unsupported by their employer for working outside of procedures, even when acting for patient benefit. Some support staff believed that strictly following procedures would keep patients and themselves safe. Dispensers described following the guidance of the pharmacist which sometimes meant working outside of procedures, but occasionally felt unable to voice concerns about not working to rule. Conclusions Organisational resilience in community pharmacy was apparent and findings from this study should help to inform policymakers and practitioners regarding factors likely to influence the implementation of procedures in community pharmacy settings. Future research should focus on exploring community pharmacy employees' intentions

  1. Multielemental analysis of 18 essential and toxic elements in amniotic fluid samples by ICP-MS: Full procedure validation and estimation of measurement uncertainty.

    PubMed

    Markiewicz, B; Sajnóg, A; Lorenc, W; Hanć, A; Komorowicz, I; Suliburska, J; Kocyłowski, R; Barałkiewicz, D

    2017-11-01

    Amniotic fluid is the substantial factor in the development of an embryo and fetus due to the fact that water and solutes contained in it penetrate the fetal membranes in an hydrostatic and osmotic way as well as being swallowed by the fetus. Elemental composition of amniotic fluid influences the growth and health of the fetus, therefore, an analysis of amniotic fluid is important because the results would indicate abnormal levels of minerals or toxic elements. Inductively coupled plasma mass spectroscopy (ICP-MS) is often used for determination of trace and ultra-trace level elements in a wide range of matrices including biological samples because of its unique analytical capabilities. In the case of trace and ultra-trace level analysis detailed characteristics of analytical procedure as well as properties of the analytical result are particularly important. The purpose of this study was to develop a new analytical procedure for multielemental analysis of 18 elements (Al, As, Ba, Ca, Cd, Co, Cr, Cu, Mg, Mn, Ni, Pb, Sb, Se, Sr, U, V and Zn) in amniotic fluid samples using ICP-MS. Dynamic reaction cell (DRC) with two reaction gases, ammonia and oxygen, was involved in the experiment to eliminate spectral interferences. Detailed validation was conducted using 3 certified reference mterials (CRMs) and real amniotic fluid samples collected from patients. Repeatability for all analyzed analytes was found to range from 0.70% to 8.0% and for intermediate precision results varied from 1.3% to 15%. Trueness expressed as recovery ranged from 80% to 125%. Traceability was assured through the analyses of CRMs. Uncertainty of the results was also evaluated using single-laboratory validation approach. The obtained expanded uncertainty (U) results for CRMs, expressed as a percentage of the concentration of an analyte, were found to be between 8.3% for V and 45% for Cd. Standard uncertainty of the precision was found to have a greater influence on the combined standard uncertainty

  2. Patent Network Analysis and Quadratic Assignment Procedures to Identify the Convergence of Robot Technologies

    PubMed Central

    Lee, Woo Jin; Lee, Won Kyung

    2016-01-01

    Because of the remarkable developments in robotics in recent years, technological convergence has been active in this area. We focused on finding patterns of convergence within robot technology using network analysis of patents in both the USPTO and KIPO. To identify the variables that affect convergence, we used quadratic assignment procedures (QAP). From our analysis, we observed the patent network ecology related to convergence and found technologies that have great potential to converge with other robotics technologies. The results of our study are expected to contribute to setting up convergence based R&D policies for robotics, which can lead new innovation. PMID:27764196

  3. Do procedures for verbal reporting of thinking have to be reactive? A meta-analysis and recommendations for best reporting methods.

    PubMed

    Fox, Mark C; Ericsson, K Anders; Best, Ryan

    2011-03-01

    Since its establishment, psychology has struggled to find valid methods for studying thoughts and subjective experiences. Thirty years ago, Ericsson and Simon (1980) proposed that participants can give concurrent verbal expression to their thoughts (think aloud) while completing tasks without changing objectively measurable performance (accuracy). In contrast, directed requests for concurrent verbal reports, such as explanations or directions to describe particular kinds of information, were predicted to change thought processes as a consequence of the need to generate this information, thus altering performance. By comparing performance of concurrent verbal reporting conditions with their matching silent control condition, Ericsson and Simon found several studies demonstrating that directed verbalization was associated with changes in performance. In contrast, the lack of effects of thinking aloud was merely suggested by a handful of experimental studies. In this article, Ericsson and Simon's model is tested by a meta-analysis of 94 studies comparing performance while giving concurrent verbalizations to a matching condition without verbalization. Findings based on nearly 3,500 participants show that the "think-aloud" effect size is indistinguishable from zero (r = -.03) and that this procedure remains nonreactive even after statistically controlling additional factors such as task type (primarily visual or nonvisual). In contrast, procedures that entail describing or explaining thoughts and actions are significantly reactive, leading to higher performance than silent control conditions. All verbal reporting procedures tend to increase times to complete tasks. These results suggest that think-aloud should be distinguished from other methods in future studies. Theoretical and practical implications are discussed. (c) 2011 APA, all rights reserved.

  4. Dispersed particle extraction--a new procedure for trace element enrichment from natural aqueous samples with subsequent ICP-OES analysis.

    PubMed

    Bauer, Gerald; Neouze, Marie-Alexandra; Limbeck, Andreas

    2013-01-15

    A novel sample pre-treatment method for multi trace element enrichment from environmental waters prior to optical emission spectrometry analysis with inductively coupled plasma (ICP-OES) is proposed, based on dispersed particle extraction (DPE). This method is based on the use of silica nanoparticles functionalized with strong cation exchange ligands. After separation from the investigated sample solution, the nanoparticles used for the extraction are directly introduced in the ICP for measurement of the adsorbed target analytes. A prerequisite for the successful application of the developed slurry approach is the use of sorbent particles with a mean size of 500 nm instead of commercially available μm sized beads. The proposed method offers the known advantages of common bead-injection (BI) techniques, and further circumvents the elution step required in conventional solid phase extraction procedures. With the use of 14.4 mL sample and addition of ammonium acetate buffer and particle slurry limits of detection (LODs) from 0.03 μg L(-1) for Be to 0.48 μg L(-1) for Fe, with relative standard deviations ranging from 1.7% for Fe and 5.5% for Cr and an average enrichment factor of 10.4 could be achieved. By implementing this method the possibility to access sorbent materials with irreversible bonding mechanisms for sample pre-treatment is established, thus improvements in the selectivity of sample pre-treatment procedures can be achieved. The presented procedure was tested for accuracy with NIST standard reference material 1643e (fresh water) and was applied to drinking water samples from the vicinity of Vienna. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Application of factor analysis to the water quality in reservoirs

    NASA Astrophysics Data System (ADS)

    Silva, Eliana Costa e.; Lopes, Isabel Cristina; Correia, Aldina; Gonçalves, A. Manuela

    2017-06-01

    In this work we present a Factor Analysis of chemical and environmental variables of the water column and hydro-morphological features of several Portuguese reservoirs. The objective is to reduce the initial number of variables, keeping their common characteristics. Using the Factor Analysis, the environmental variables measured in the epilimnion and in the hypolimnion, together with the hydromorphological characteristics of the dams were reduced from 63 variables to only 13 factors, which explained a total of 83.348% of the variance in the original data. After performing rotation using the Varimax method, the relations between the factors and the original variables got clearer and more explainable, which provided a Factor Analysis model for these environmental variables using 13 varifactors: Water quality and distance to the source, Hypolimnion chemical composition, Sulfite-reducing bacteria and nutrients, Coliforms and faecal streptococci, Reservoir depth, Temperature, Location, among other factors.

  6. Estimating the Cost of Neurosurgical Procedures in a Low-Income Setting: An Observational Economic Analysis.

    PubMed

    Abdelgadir, Jihad; Tran, Tu; Muhindo, Alex; Obiga, Doomwin; Mukasa, John; Ssenyonjo, Hussein; Muhumza, Michael; Kiryabwire, Joel; Haglund, Michael M; Sloan, Frank A

    2017-05-01

    There are no data on cost of neurosurgery in low-income and middle-income countries. The objective of this study was to estimate the cost of neurosurgical procedures in a low-resource setting to better inform resource allocation and health sector planning. In this observational economic analysis, microcosting was used to estimate the direct and indirect costs of neurosurgical procedures at Mulago National Referral Hospital (Kampala, Uganda). During the study period, October 2014 to September 2015, 1440 charts were reviewed. Of these patients, 434 had surgery, whereas the other 1006 were treated nonsurgically. Thirteen types of procedures were performed at the hospital. The estimated mean cost of a neurosurgical procedure was $542.14 (standard deviation [SD], $253.62). The mean cost of different procedures ranged from $291 (SD, $101) for burr hole evacuations to $1,221 (SD, $473) for excision of brain tumors. For most surgeries, overhead costs represented the largest proportion of the total cost (29%-41%). This is the first study using primary data to determine the cost of neurosurgery in a low-resource setting. Operating theater capacity is likely the binding constraint on operative volume, and thus, investing in operating theaters should achieve a higher level of efficiency. Findings from this study could be used by stakeholders and policy makers for resource allocation and to perform economic analyses to establish the value of neurosurgery in achieving global health goals. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE--COMPENDIUM OF METHODS FOR ANALYSIS OF TRACE METALS AND PESTICIDES IN DIETARY SAMPLES USING TOTAL DIET STUDY PROCEDURES (FDA-COMPENDIUM)

    EPA Science Inventory

    This compendium contains seven SOPs developed by Food and Drug Administration (FDA) laboratories for methods of analyzing trace metals in dietary samples collected using Total Diet study procedures. The SOPs include the following: (1) Quality Control for Analysis of NHEXAS Food o...

  8. Pre-procedural bioimpedance vectorial analysis of fluid status and prediction of contrast-induced acute kidney injury.

    PubMed

    Maioli, Mauro; Toso, Anna; Leoncini, Mario; Musilli, Nicola; Bellandi, Francesco; Rosner, Mitchell H; McCullough, Peter A; Ronco, Claudio

    2014-04-15

    The aim of this study was to evaluate the relationship between pre-procedural fluid status assessed by bioimpedance vector analysis (BIVA) and development of contrast-induced acute kidney injury (CI-AKI). Accurate fluid management in patients undergoing angiographic procedures is of critical importance in limiting the risk of CI-AKI. Therefore, establishing peri-procedural fluid volume related to increased risk of CI-AKI development is essential. We evaluated the fluid status by BIVA of 900 consecutive patients with stable coronary artery disease (CAD) immediately before coronary angiography, measuring the resistance/height (R/H) ratio and impedance/height (Z/H) vector. CI-AKI was defined as an increase in serum creatinine ≥0.5 mg/dl above baseline within 3 days after contrast administration (iodixanol). CI-AKI occurred in 54 patients (6.0%). Pre-procedural R/H ratios were significantly higher in patients with CI-AKI than without CI-AKI (395 ± 71 Ohm/m vs. 352 ± 58 Ohm/m, p = 0.001 for women; 303 ± 59 Ohm/m vs. 279 ± 45 Ohm/m, p = 0.009 for men), indicating lower fluid volume in the patients with CI-AKI. When patients were stratified according to R/H ratio, there was an almost 3-fold higher risk in patients with higher values (odds ratio [OR]: 2.9; 95% confidence interval [CI]: 1.5 to 5.5; p = 0.002). The optimal receiver-operating characteristic curve analysis threshold values of R/H ratio for predicting CI-AKI were 380 Ohm/m for women and 315 Ohm/m for men. R/H ratio above these thresholds was found to be a significant and independent predictor of CI-AKI (OR: 3.1; 95% CI: 1.8 to 5.5; p = 0.001). Lower fluid status evaluated by BIVA immediately before contrast medium administration resulted in a significant and independent predictor of CI-AKI in patients with stable CAD. This simple noninvasive analysis should be tested in guiding tailored volume repletion. Copyright © 2014 American College of Cardiology Foundation. Published by Elsevier Inc. All rights

  9. Electrically evoked compound action potentials artefact rejection by independent component analysis: procedure automation.

    PubMed

    Akhoun, Idrick; McKay, Colette; El-Deredy, Wael

    2015-01-15

    Independent-components-analysis (ICA) successfully separated electrically-evoked compound action potentials (ECAPs) from the stimulation artefact and noise (ECAP-ICA, Akhoun et al., 2013). This paper shows how to automate the ECAP-ICA artefact cancellation process. Raw-ECAPs without artefact rejection were consecutively recorded for each stimulation condition from at least 8 intra-cochlear electrodes. Firstly, amplifier-saturated recordings were discarded, and the data from different stimulus conditions (different current-levels) were concatenated temporally. The key aspect of the automation procedure was the sequential deductive source categorisation after ICA was applied with a restriction to 4 sources. The stereotypical aspect of the 4 sources enables their automatic classification as two artefact components, a noise and the sought ECAP based on theoretical and empirical considerations. The automatic procedure was tested using 8 cochlear implant (CI) users and one to four stimulus electrodes. The artefact and noise sources were successively identified and discarded, leaving the ECAP as the remaining source. The automated ECAP-ICA procedure successfully extracted the correct ECAPs compared to standard clinical forward masking paradigm in 22 out of 26 cases. ECAP-ICA does not require extracting the ECAP from a combination of distinct buffers as it is the case with regular methods. It is an alternative that does not have the possible bias of traditional artefact rejections such as alternate-polarity or forward-masking paradigms. The ECAP-ICA procedure bears clinical relevance, for example as the artefact rejection sub-module of automated ECAP-threshold detection techniques, which are common features of CI clinical fitting software. Copyright © 2014. Published by Elsevier B.V.

  10. Uncertainty analysis routine for the Ocean Thermal Energy Conversion (OTEC) biofouling measurement device and data reduction procedure. [HTCOEF code

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

    Bird, S.P.

    1978-03-01

    Biofouling and corrosion of heat exchanger surfaces in Ocean Thermal Energy Conversion (OTEC) systems may be controlling factors in the potential success of the OTEC concept. Very little is known about the nature and behavior of marine fouling films at sites potentially suitable for OTEC power plants. To facilitate the acquisition of needed data, a biofouling measurement device developed by Professor J. G. Fetkovich and his associates at Carnegie-Mellon University (CMU) has been mass produced for use by several organizations in experiments at a variety of ocean sites. The CMU device is designed to detect small changes in thermal resistancemore » associated with the formation of marine microfouling films. An account of the work performed at the Pacific Northwest Laboratory (PNL) to develop a computerized uncertainty analysis for estimating experimental uncertainties of results obtained with the CMU biofouling measurement device and data reduction scheme is presented. The analysis program was written as a subroutine to the CMU data reduction code and provides an alternative to the CMU procedure for estimating experimental errors. The PNL code was used to analyze sample data sets taken at Keahole Point, Hawaii; St. Croix, the Virgin Islands; and at a site in the Gulf of Mexico. The uncertainties of the experimental results were found to vary considerably with the conditions under which the data were taken. For example, uncertainties of fouling factors (where fouling factor is defined as the thermal resistance of the biofouling layer) estimated from data taken on a submerged buoy at Keahole Point, Hawaii were found to be consistently within 0.00006 hr-ft/sup 2/-/sup 0/F/Btu, while corresponding values for data taken on a tugboat in the Gulf of Mexico ranged up to 0.0010 hr-ft/sup 2/-/sup 0/F/Btu. Reasons for these differences are discussed.« less

  11. An Aggregate IRT Procedure for Exploratory Factor Analysis

    ERIC Educational Resources Information Center

    Camilli, Gregory; Fox, Jean-Paul

    2015-01-01

    An aggregation strategy is proposed to potentially address practical limitation related to computing resources for two-level multidimensional item response theory (MIRT) models with large data sets. The aggregate model is derived by integration of the normal ogive model, and an adaptation of the stochastic approximation expectation maximization…

  12. A procedure for partitioning bulk sediments into distinct grain-size fractions for geochemical analysis

    USGS Publications Warehouse

    Barbanti, A.; Bothner, Michael H.

    1993-01-01

    A method to separate sediments into discrete size fractions for geochemical analysis has been tested. The procedures were chosen to minimize the destruction or formation of aggregates and involved gentle sieving and settling of wet samples. Freeze-drying and sonication pretreatments, known to influence aggregates, were used for comparison. Freeze-drying was found to increase the silt/clay ratio by an average of 180 percent compared to analysis of a wet sample that had been wet sieved only. Sonication of a wet sample decreased the silt/clay ratio by 51 percent. The concentrations of metals and organic carbon in the separated fractions changed depending on the pretreatment procedures in a manner consistent with the hypothesis that aggregates consist of fine-grained organic- and metal-rich particles. The coarse silt fraction of a freeze-dried sample contained 20–44 percent higher concentrations of Zn, Cu, and organic carbon than the coarse silt fraction of the wet sample. Sonication resulted in concentrations of these analytes that were 18–33 percent lower in the coarse silt fraction than found in the wet sample. Sonication increased the concentration of lead in the clay fraction by an average of 40 percent compared to an unsonicated sample. Understanding the magnitude of change caused by different analysis protocols is an aid in designing future studies that seek to interpret the spatial distribution of contaminated sediments and their transport mechanisms.

  13. Considering Horn's Parallel Analysis from a Random Matrix Theory Point of View.

    PubMed

    Saccenti, Edoardo; Timmerman, Marieke E

    2017-03-01

    Horn's parallel analysis is a widely used method for assessing the number of principal components and common factors. We discuss the theoretical foundations of parallel analysis for principal components based on a covariance matrix by making use of arguments from random matrix theory. In particular, we show that (i) for the first component, parallel analysis is an inferential method equivalent to the Tracy-Widom test, (ii) its use to test high-order eigenvalues is equivalent to the use of the joint distribution of the eigenvalues, and thus should be discouraged, and (iii) a formal test for higher-order components can be obtained based on a Tracy-Widom approximation. We illustrate the performance of the two testing procedures using simulated data generated under both a principal component model and a common factors model. For the principal component model, the Tracy-Widom test performs consistently in all conditions, while parallel analysis shows unpredictable behavior for higher-order components. For the common factor model, including major and minor factors, both procedures are heuristic approaches, with variable performance. We conclude that the Tracy-Widom procedure is preferred over parallel analysis for statistically testing the number of principal components based on a covariance matrix.

  14. Restorative Procedures in Colonic Crohn Disease

    PubMed Central

    Martin, Sean T.; Vogel, Jon D.

    2013-01-01

    Surgical management for refractory Crohn colitis often involves creation of a temporary or permanent stoma. Traditionally, the procedure of choice has been a total proctocolectomy with permanent ileostomy. However, restorative procedures that help to avoid a permanent stoma are being used with more frequency. In this article, the authors will address these procedures, including colocolonic anastomosis, ileorectal anastomosis, ileal pouch rectal anastomosis, and ileal pouch anal anastomosis. Factors that may influence one's decision to perform these procedures, such as patient age and nutritional status, medical comorbidities, sphincter function, desire to avoid a permanent ostomy, and prior medical therapy, will be discussed. Functional outcomes regarding these procedures will also be described. One should keep in mind that surgery does not cure Crohn disease and that postoperative long-term management is essential in preventing progression or recurrence of disease. PMID:24436657

  15. National Trends of Simple Prostatectomy for Benign Prostatic Hyperplasia With an Analysis of Risk Factors for Adverse Perioperative Outcomes.

    PubMed

    Pariser, Joseph J; Pearce, Shane M; Patel, Sanjay G; Bales, Gregory T

    2015-10-01

    To examine the national trends of simple prostatectomy (SP) for benign prostatic hyperplasia (BPH) focusing on perioperative outcomes and risk factors for complications. The National Inpatient Sample (2002-2012) was utilized to identify patients with BPH undergoing SP. Analysis included demographics, hospital details, associated procedures, and operative approach (open, robotic, or laparoscopic). Outcomes included complications, length of stay, charges, and mortality. Multivariate logistic regression was used to determine the risk factors for perioperative complications. Linear regression was used to assess the trends in the national annual utilization of SP. The study population included 35,171 patients. Median length of stay was 4 days (interquartile range 3-6). Cystolithotomy was performed concurrently in 6041 patients (17%). The overall complication rate was 28%, with bleeding occurring most commonly. In total, 148 (0.4%) patients experienced in-hospital mortality. On multivariate analysis, older age, black race, and overall comorbidity were associated with greater risk of complications while the use of a minimally invasive approach and concurrent cystolithotomy had a decreased risk. Over the study period, the national use of simple prostatectomy decreased, on average, by 145 cases per year (P = .002). By 2012, 135/2580 procedures (5%) were performed using a minimally invasive approach. The nationwide utilization of SP for BPH has decreased. Bleeding complications are common, but perioperative mortality is low. Patients who are older, black race, or have multiple comorbidities are at higher risk of complications. Minimally invasive approaches, which are becoming increasingly utilized, may reduce perioperative morbidity. Copyright © 2015 Elsevier Inc. All rights reserved.

  16. Multi-response permutation procedure as an alternative to the analysis of variance: an SPSS implementation.

    PubMed

    Cai, Li

    2006-02-01

    A permutation test typically requires fewer assumptions than does a comparable parametric counterpart. The multi-response permutation procedure (MRPP) is a class of multivariate permutation tests of group difference useful for the analysis of experimental data. However, psychologists seldom make use of the MRPP in data analysis, in part because the MRPP is not implemented in popular statistical packages that psychologists use. A set of SPSS macros implementing the MRPP test is provided in this article. The use of the macros is illustrated by analyzing example data sets.

  17. Is isomerism a risk factor for intestinal volvulus?

    PubMed

    Landisch, Rachel M; Loomba, Rohit S; Salazar, Jose H; Buelow, Matthew W; Frommelt, Michele; Anderson, Robert H; Wagner, Amy J

    2018-03-06

    Isomerism, or heterotaxy syndrome, affects many organ systems anatomically and functionally. Intestinal malrotation is common in patients with isomerism. Despite a low reported risk of volvulus, some physicians perform routine screening and prophylactic Ladd procedures on asymptomatic patients with isomerism who are found to have intestinal malrotation. The primary aim of this study was to determine if isomerism is an independent risk factor for volvulus. Kid's Inpatient Database data from 1997 to 2012 was utilized for this study. Characteristics of admissions with and without isomerism were compared with a particular focus on intestinal malrotation, volvulus, and Ladd procedure. A logistic regression was conducted to determine independent risk factors for volvulus with respect to isomerism. 15,962,403 inpatient admissions were included in the analysis, of which 7970 (0.05%) patients had isomerism, and 6 patients (0.1%) developed volvulus. Isomerism was associated with a 52-fold increase in the odds of intestinal malrotation by univariate analysis. Of 251 with isomerism and intestinal malrotation, only 2.4% experienced volvulus. Logistic regression demonstrated that isomerism was not an independent risk factor for volvulus. Isomerism is associated with an increased risk of intestinal malrotation but is not an independent risk factor for volvulus. Prognosis study. Level III. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. A replication of a factor analysis of motivations for trapping

    USGS Publications Warehouse

    Schroeder, Susan; Fulton, David C.

    2015-01-01

    Using a 2013 sample of Minnesota trappers, we employed confirmatory factor analysis to replicate an exploratory factor analysis of trapping motivations conducted by Daigle, Muth, Zwick, and Glass (1998).  We employed the same 25 items used by Daigle et al. and tested the same five-factor structure using a recent sample of Minnesota trappers. We also compared motivations in our sample to those reported by Daigle et el.

  19. 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)

  20. Factors associated with patient, and diagnostic delays in Chinese TB patients: a systematic review and meta-analysis.

    PubMed

    Li, Ying; Ehiri, John; Tang, Shenglan; Li, Daikun; Bian, Yongqiao; Lin, Hui; Marshall, Caitlin; Cao, Jia

    2013-07-02

    Delay in seeking care is a major impediment to effective management of tuberculosis (TB) in China. To elucidate factors that underpin patient and diagnostic delays in TB management, we conducted a systematic review and meta-analysis of factors that are associated with delays in TB care-seeking and diagnosis in the country. This review was prepared following standard procedures of the Cochrane Collaboration and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement and checklist. Relevant studies published up to November 2012 were identified from three major international and Chinese literature databases: Medline/PubMed, EMBASE and CNKI (China National Knowledge Infrastructure). We included 29 studies involving 38,947 patients from 17 provinces in China. Qualitative analysis showed that key individual level determinants of delays included socio-demographic and economic factors, mostly poverty, rural residence, lack of health insurance, lower educational attainment, stigma and poor knowledge of TB. Health facility determinants included limited availability of resources to perform prompt diagnosis, lack of qualified health workers and geographical barriers.Quantitative meta-analysis indicated that living in rural areas was a risk factor for patient delays (pooled odds ratio (OR) (95% confidence interval (CI)): 1.79 (1.62, 1.98)) and diagnostic delays (pooled OR (95% CI): 1.40 (1.23, 1.59)). Female patients had higher risk of patient delay (pooled OR (95% CI): 1.94 (1.13, 3.33)). Low educational attainment (primary school and below) was also a risk factor for patient delay (pooled OR (95% CI): 2.14 (1.03, 4.47)). The practice of seeking care first from Traditional Chinese Medicine (TMC) providers was also identified as a risk factor for diagnostic delay (pooled OR (95% CI): 5.75 (3.03, 10.94)). Patient and diagnostic delays in TB care are mediated by individual and health facility factors. Population-based interventions that seek to reduce TB

  1. 40 CFR 1065.12 - Approval of alternate procedures.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Applicability and General Provisions § 1065.12 Approval of... individual engine manufacturer may request to use an alternate procedure. This also means that an instrument... show that your engines comply with all applicable emission standards. (3) Any relevant factors...

  2. 40 CFR 1065.12 - Approval of alternate procedures.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Applicability and General Provisions § 1065.12 Approval of... individual engine manufacturer may request to use an alternate procedure. This also means that an instrument... show that your engines comply with all applicable emission standards. (3) Any relevant factors...

  3. 40 CFR 1065.12 - Approval of alternate procedures.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Applicability and General Provisions § 1065.12 Approval of... individual engine manufacturer may request to use an alternate procedure. This also means that an instrument... show that your engines comply with all applicable emission standards. (3) Any relevant factors...

  4. A General Procedure to Assess the Internal Structure of a Noncognitive Measure--The Student360 Insight Program (S360) Time Management Scale. Research Report. ETS RR-11-42

    ERIC Educational Resources Information Center

    Ling, Guangming; Rijmen, Frank

    2011-01-01

    The factorial structure of the Time Management (TM) scale of the Student 360: Insight Program (S360) was evaluated based on a national sample. A general procedure with a variety of methods was introduced and implemented, including the computation of descriptive statistics, exploratory factor analysis (EFA), and confirmatory factor analysis (CFA).…

  5. Biliary bypass surgery - Analysis of indications & outcome of different procedures.

    PubMed

    Hussain Talpur, K Altaf; Mahmood Malik, Arshad; Iqbal Memon, Amir; Naeem Qureshi, Jawed; Khan Sangrasi, Ahmed; Laghari, Abdul Aziz

    2013-05-01

    This study reports the indications and outcome of various biliary bypass surgical procedures from a single centre over a period of 10 years. This is a prospective observational study conducted over a period of 10 years (January 2001-december 2010). A total of 1500 patients were included, who underwent pancreatico-biliary surgery due to common bile duct (CBD) stones, congenital anomalies of biliary tree, unoperable pancreatico-biliary malignancies, CBD strictures and cases who developed iatrogenic biliary injuries during cholecystectomy (both open & laproscopic) during this period of time. The patients who required biliary bypass surgery were further analysed for indications and outcome. Out of 1500 patients 83(5.53%) required biliary bypass surgical procedures. The CBD stones were observed as the most common indication (25.3%), followed by CBD injuries after open(10.84%) or laproscopic-cholecystectomy (14.46%), carcinoma head of pancreas (12.05%) and CBD obstruction(14.46%) either due to CBD strictures or unknown distal obstruction. Roux-en-Y-hepatico-jejunostomy (26.51%) was the most frequently performed procedure, followed by choledochoduodenostomy and Roux-en-Y choledocho-jejunostomy (i.e. 25.3% and 12.05% respectively). Roux-en-Y biliary bypass procedure was observed to be associated with better outcome in terms of rate of complications as well duration of hospital stay. Biliary bypass surgical procedures are the better options to restore the continuity of biliary system in patients with iatrogenic biliary tree injuries and un-operable pancreatico-biliary malignancy. Roux-en-Y biliary bypass procedure is safe and problem solving method in these cases.

  6. Factor Analysis of the Brazilian Version of UPPS Impulsive Behavior Scale

    PubMed Central

    Sediyama, Cristina Y. N.; Moura, Ricardo; Garcia, Marina S.; da Silva, Antonio G.; Soraggi, Carolina; Neves, Fernando S.; Albuquerque, Maicon R.; Whiteside, Setephen P.; Malloy-Diniz, Leandro F.

    2017-01-01

    Objective: To examine the internal consistency and factor structure of the Brazilian adaptation of the UPPS Impulsive Behavior Scale. Methods: UPPS is a self-report scale composed by 40 items assessing four factors of impulsivity: (a) urgency, (b) lack of premeditation; (c) lack of perseverance; (d) sensation seeking. In the present study 384 participants (278 women and 106 men), who were recruited from schools, universities, leisure centers and workplaces fulfilled the UPPS scale. An exploratory factor analysis was performed by using Varimax factor rotation and Kaiser Normalization, and we also conducted two confirmatory analyses to test the independency of the UPPS components found in previous analysis. Results: Results showed a decrease in mean UPPS total scores with age and this analysis showed that the youngest participants (below 30 years) scored significantly higher than the other groups over 30 years. No difference in gender was found. Cronbach’s alpha, results indicated satisfactory values for all subscales, with similar high values for the subscales and confirmatory factor analysis indexes also indicated a poor model fit. The results of two exploratory factor analysis were satisfactory. Conclusion: Our results showed that the Portuguese version has the same four-factor structure of the original and previous translations of the UPPS. PMID:28484414

  7. Factor Analysis of the Brazilian Version of UPPS Impulsive Behavior Scale.

    PubMed

    Sediyama, Cristina Y N; Moura, Ricardo; Garcia, Marina S; da Silva, Antonio G; Soraggi, Carolina; Neves, Fernando S; Albuquerque, Maicon R; Whiteside, Setephen P; Malloy-Diniz, Leandro F

    2017-01-01

    Objective: To examine the internal consistency and factor structure of the Brazilian adaptation of the UPPS Impulsive Behavior Scale. Methods: UPPS is a self-report scale composed by 40 items assessing four factors of impulsivity: (a) urgency, (b) lack of premeditation; (c) lack of perseverance; (d) sensation seeking. In the present study 384 participants (278 women and 106 men), who were recruited from schools, universities, leisure centers and workplaces fulfilled the UPPS scale. An exploratory factor analysis was performed by using Varimax factor rotation and Kaiser Normalization, and we also conducted two confirmatory analyses to test the independency of the UPPS components found in previous analysis. Results: Results showed a decrease in mean UPPS total scores with age and this analysis showed that the youngest participants (below 30 years) scored significantly higher than the other groups over 30 years. No difference in gender was found. Cronbach's alpha, results indicated satisfactory values for all subscales, with similar high values for the subscales and confirmatory factor analysis indexes also indicated a poor model fit. The results of two exploratory factor analysis were satisfactory. Conclusion: Our results showed that the Portuguese version has the same four-factor structure of the original and previous translations of the UPPS.

  8. Application of GIS-based Procedure on Slopeland Use Classification and Identification

    NASA Astrophysics Data System (ADS)

    KU, L. C.; LI, M. C.

    2016-12-01

    In Taiwan, the "Slopeland Conservation and Utilization Act" regulates the management of the slopelands. It categorizes the slopeland into land suitable for agricultural or animal husbandry, land suitable for forestry and land for enhanced conservation, according to the environmental factors of average slope, effective soil depth, soil erosion and parental rock. Traditionally, investigations of environmental factors require cost-effective field works. It has been confronted with many practical issues such as non-evaluated cadastral parcels, evaluation results depending on expert's opinion, difficulties in field measurement and judgment, and time consuming. This study aimed to develop a GIS-based procedure involved in the acceleration of slopeland use classification and quality improvement. First, the environmental factors of slopelands were analyzed by GIS and SPSS software. The analysis involved with the digital elevation model (DEM), soil depth map, land use map and satellite images. Second, 5% of the analyzed slopelands were selected to perform the site investigations and correct the results of classification. Finally, a 2nd examination was involved by randomly selected 2% of the analyzed slopelands to perform the accuracy evaluation. It was showed the developed procedure is effective in slopeland use classification and identification. Keywords: Slopeland Use Classification, GIS, Management

  9. New microfluidic-based sampling procedure for overcoming the hematocrit problem associated with dried blood spot analysis.

    PubMed

    Leuthold, Luc Alexis; Heudi, Olivier; Déglon, Julien; Raccuglia, Marc; Augsburger, Marc; Picard, Franck; Kretz, Olivier; Thomas, Aurélien

    2015-02-17

    Hematocrit (Hct) is one of the most critical issues associated with the bioanalytical methods used for dried blood spot (DBS) sample analysis. Because Hct determines the viscosity of blood, it may affect the spreading of blood onto the filter paper. Hence, accurate quantitative data can only be obtained if the size of the paper filter extracted contains a fixed blood volume. We describe for the first time a microfluidic-based sampling procedure to enable accurate blood volume collection on commercially available DBS cards. The system allows the collection of a controlled volume of blood (e.g., 5 or 10 μL) within several seconds. Reproducibility of the sampling volume was examined in vivo on capillary blood by quantifying caffeine and paraxanthine on 5 different extracted DBS spots at two different time points and in vitro with a test compound, Mavoglurant, on 10 different spots at two Hct levels. Entire spots were extracted. In addition, the accuracy and precision (n = 3) data for the Mavoglurant quantitation in blood with Hct levels between 26% and 62% were evaluated. The interspot precision data were below 9.0%, which was equivalent to that of a manually spotted volume with a pipet. No Hct effect was observed in the quantitative results obtained for Hct levels from 26% to 62%. These data indicate that our microfluidic-based sampling procedure is accurate and precise and that the analysis of Mavoglurant is not affected by the Hct values. This provides a simple procedure for DBS sampling with a fixed volume of capillary blood, which could eliminate the recurrent Hct issue linked to DBS sample analysis.

  10. Relations among conceptual knowledge, procedural knowledge, and procedural flexibility in two samples differing in prior knowledge.

    PubMed

    Schneider, Michael; Rittle-Johnson, Bethany; Star, Jon R

    2011-11-01

    Competence in many domains rests on children developing conceptual and procedural knowledge, as well as procedural flexibility. However, research on the developmental relations between these different types of knowledge has yielded unclear results, in part because little attention has been paid to the validity of the measures or to the effects of prior knowledge on the relations. To overcome these problems, we modeled the three constructs in the domain of equation solving as latent factors and tested (a) whether the predictive relations between conceptual and procedural knowledge were bidirectional, (b) whether these interrelations were moderated by prior knowledge, and (c) how both constructs contributed to procedural flexibility. We analyzed data from 2 measurement points each from two samples (Ns = 228 and 304) of middle school students who differed in prior knowledge. Conceptual and procedural knowledge had stable bidirectional relations that were not moderated by prior knowledge. Both kinds of knowledge contributed independently to procedural flexibility. The results demonstrate how changes in complex knowledge structures contribute to competence development.

  11. Structural-Vibration-Response Data Analysis

    NASA Technical Reports Server (NTRS)

    Smith, W. R.; Hechenlaible, R. N.; Perez, R. C.

    1983-01-01

    Computer program developed as structural-vibration-response data analysis tool for use in dynamic testing of Space Shuttle. Program provides fast and efficient time-domain least-squares curve-fitting procedure for reducing transient response data to obtain structural model frequencies and dampings from free-decay records. Procedure simultaneously identifies frequencies, damping values, and participation factors for noisy multiple-response records.

  12. A Factor Analysis of Learning Data and Selected Ability Test Scores

    ERIC Educational Resources Information Center

    Jones, Dorothy L.

    1976-01-01

    A verbal concept-learning task permitting the externalizing and quantifying of learning behavior and 16 ability tests were administered to female graduate students. Data were analyzed by alpha factor analysis and incomplete image analysis. Six alpha factors and 12 image factors were extracted and orthogonally rotated. Four areas of cognitive…

  13. Risk factors and prognosis for neonatal sepsis in southeastern Mexico: analysis of a four-year historic cohort follow-up

    PubMed Central

    2012-01-01

    Background Neonatal sepsis is a worldwide public health issue in which, depending on the studied population, marked variations concerning its risk and prognostic factors have been reported. The aim of this study was to assess risk and prognostic factors for neonatal sepsis prevailing at a medical unit in southeastern Mexico. Thus, we used a historic cohort design to assess the association between a series of neonates and their mothers, in addition to hospital evolution features and the risk and prognosis of neonatal sepsis (defined by Pediatric Sepsis Consensus [PSC] criteria) in 11,790 newborns consecutively admitted to a Neonatology Service in Mérida, Mexico, between 2004 and 2007. Results Sepsis was found in 514 of 11,790 (4.3 %) newborns; 387 of these cases were categorized as early-onset (<72 h) (75.3 %) and 127, as late-onset (>72 h) (24.7 %). After logistic regression, risk factors for sepsis included the following: low birth weight; prematurity; abnormal amniotic fluid; premature membrane rupture (PMR) at >24 h; respiratory complications, and the requirement of assisted ventilation, O2 Inspiration fraction (IF) >60 %, or a surgical procedure. Some of these factors were differentially associated with early- or late-onset neonatal sepsis. The overall mortality rate of sepsis was 9.5 %. A marked difference in the mortality rate was found between early- and late-onset sepsis (p >0.0001). After Cox analysis, factors associated with mortality in newborns with sepsis comprised the following: prematurity; low birth weight; low Apgar score; perinatal asphyxia, and the requirement of any invasive medical or surgical procedure. Conclusions The incidence of neonatal sepsis in southeastern Mexico was 4.3 %. A different risk and prognostic profile between early- and late-onset neonatal sepsis was found. PMID:22691696

  14. Soil Sampling Operating Procedure

    EPA Pesticide Factsheets

    EPA Region 4 Science and Ecosystem Support Division (SESD) document that describes general and specific procedures, methods, and considerations when collecting soil samples for field screening or laboratory analysis.

  15. Sediment Sampling Operating Procedure

    EPA Pesticide Factsheets

    EPA Region 4 Science and Ecosystem Support Division (SESD) document that describes general and specific procedures, methods, and considerations when collecting sediment samples for field screening or laboratory analysis.

  16. An XML Representation for Crew Procedures

    NASA Technical Reports Server (NTRS)

    Simpson, Richard C.

    2005-01-01

    NASA ensures safe operation of complex systems through the use of formally-documented procedures, which encode the operational knowledge of the system as derived from system experts. Crew members use procedure documentation on the ground for training purposes and on-board space shuttle and space station to guide their activities. Investigators at JSC are developing a new representation for procedures that is content-based (as opposed to display-based). Instead of specifying how a procedure should look on the printed page, the content-based representation will identify the components of a procedure and (more importantly) how the components are related (e.g., how the activities within a procedure are sequenced; what resources need to be available for each activity). This approach will allow different sets of rules to be created for displaying procedures on a computer screen, on a hand-held personal digital assistant (PDA), verbally, or on a printed page, and will also allow intelligent reasoning processes to automatically interpret and use procedure definitions. During his NASA fellowship, Dr. Simpson examined how various industries represent procedures (also called business processes or workflows), in areas such as manufacturing, accounting, shipping, or customer service. A useful method for designing and evaluating workflow representation languages is by determining their ability to encode various workflow patterns, which depict abstract relationships between the components of a procedure removed from the context of a specific procedure or industry. Investigators have used this type of analysis to evaluate how well-suited existing workflow representation languages are for various industries based on the workflow patterns that commonly arise across industry-specific procedures. Based on this type of analysis, it is already clear that existing workflow representations capture discrete flow of control (i.e., when one activity should start and stop based on when other

  17. A 20-year review of pectus surgery: an analysis of factors predictive of recurrence and outcomes.

    PubMed

    Tikka, Theofano; Kalkat, Maninder S; Bishay, Ehab; Steyn, Richard S; Rajesh, Pala B; Naidu, Babu

    2016-12-01

    Only a few studies report the long-term outcomes following repair of pectus excavatum (PE) and pectus carinatum (PC). Predictors of recurrence after surgery are important in this group of young patients. The purpose of this study was to assess the short- and long-term outcomes of both PE and PC and identify factors associated with postoperative complications and pectus recurrence. This was a retrospective observational study that included all patients who underwent primary or recurrent repair of PC and PE in a regional thoracic centre over 20 years. Patients' demographics, type of surgery, complications and recurrence were recorded. Logistic regression analysis was performed to identify factors predictive of pectus recurrence. A total of 297 patients were included (262 men and 35 women). The mean age was 19.8 years (95% CI 19.3-20.5). A total of 169 patients had surgery for PE and 127 for PC. A total of 243 patients had a modified Ravitch procedure (166 without a bar) and 53 patients underwent the Nuss repair. The main postoperative complications were wound infection and bleeding or haematoma. The recurrence rate over the mean follow-up period of 8.6 years was 10%. In PE, patients treated with the Ravitch procedure with the bar experienced more complications. Univariate and multivariate analyses showed that PE patients who developed a complication had a significantly increased chance of recurrence. No risk factors were linked with recurrence of PC. Life-transforming pectus surgery can be performed with low morbidity and good long-term outcomes. Recurrence of PE deformity is associated with the development of postoperative complications. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

  18. Prescriptive Profile Procedure for Children With Learning Disabilities.

    ERIC Educational Resources Information Center

    Levine, Eleanor; Fineman, Carol

    The Prescriptive Profile Procedure (PPP) attempts to provide teachers of learning disabled elementary school children with a procedure of individualized diagnosis and educational prescription which encompasses strengths and weaknesses in prerequisite skills, basic school subjects, and behavioral factors. A competency statement and six to 12…

  19. Biological risk factors for suicidal behaviors: a meta-analysis

    PubMed Central

    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

  20. A BPM calibration procedure using TBT data

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

    Yang, M.J.; Crisp, J.; Prieto, P.

    2007-06-01

    Accurate BPM calibration is crucial for lattice analysis. It is also reassuring when the calibration can be independently verified. This paper outlines a procedure that can extract BPM calibration information from TBT orbit data. The procedure is developed as an extension to the Turn-By-Turn lattice analysis [1]. Its application to data from both Recycler Ring and Main Injector (MI) at Fermilab have produced very encouraging results. Some specifics in hardware design will be mentioned to contrast that of analysis results.

  1. Polarization of perceived Procedural Justice.

    PubMed

    Flint, Douglas H; Hernandez-Marrero, Pablo; Wielemaker, Martin

    2006-02-01

    This study examined polarization of perceptions of Procedural Justice. Two polarization mechanisms are examined, Persuasive Arguments and Social Comparisons. Participants were students enrolled in a first-year introductory business class. There were 216 participants in the Persuasive Arguments study, 429 in the Social Comparisons study. The average age of all participants was 22.3 yr. (SD = 2.1); 56% were women. Fields of study represented were business, engineering, information technology, and sports. Analysis showed under conditions of low Procedural Justice, polarization effects were only found with the Persuasive Arguments mechanism. Under conditions of high Procedural Justice, polarization effects were only found with Social Comparisons. Implications for group polarization and Procedural Justice theories are considered.

  2. An integrated portfolio optimisation procedure based on data envelopment analysis, artificial bee colony algorithm and genetic programming

    NASA Astrophysics Data System (ADS)

    Hsu, Chih-Ming

    2014-12-01

    Portfolio optimisation is an important issue in the field of investment/financial decision-making and has received considerable attention from both researchers and practitioners. However, besides portfolio optimisation, a complete investment procedure should also include the selection of profitable investment targets and determine the optimal timing for buying/selling the investment targets. In this study, an integrated procedure using data envelopment analysis (DEA), artificial bee colony (ABC) and genetic programming (GP) is proposed to resolve a portfolio optimisation problem. The proposed procedure is evaluated through a case study on investing in stocks in the semiconductor sub-section of the Taiwan stock market for 4 years. The potential average 6-month return on investment of 9.31% from 1 November 2007 to 31 October 2011 indicates that the proposed procedure can be considered a feasible and effective tool for making outstanding investment plans, and thus making profits in the Taiwan stock market. Moreover, it is a strategy that can help investors to make profits even when the overall stock market suffers a loss.

  3. A Statistical Selection Strategy for Normalization Procedures in LC-MS Proteomics Experiments through Dataset Dependent Ranking of Normalization Scaling Factors

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

    Webb-Robertson, Bobbie-Jo M.; Matzke, Melissa M.; Jacobs, Jon M.

    2011-12-01

    Quantification of LC-MS peak intensities assigned during peptide identification in a typical comparative proteomics experiment will deviate from run-to-run of the instrument due to both technical and biological variation. Thus, normalization of peak intensities across a LC-MS proteomics dataset is a fundamental step in pre-processing. However, the downstream analysis of LC-MS proteomics data can be dramatically affected by the normalization method selected . Current normalization procedures for LC-MS proteomics data are presented in the context of normalization values derived from subsets of the full collection of identified peptides. The distribution of these normalization values is unknown a priori. If theymore » are not independent from the biological factors associated with the experiment the normalization process can introduce bias into the data, which will affect downstream statistical biomarker discovery. We present a novel approach to evaluate normalization strategies, where a normalization strategy includes the peptide selection component associated with the derivation of normalization values. Our approach evaluates the effect of normalization on the between-group variance structure in order to identify candidate normalization strategies that improve the structure of the data without introducing bias into the normalized peak intensities.« less

  4. [Successful management of neurosurgical procedures with continuous infusion of recombinant factor IX in a child with hemophilia B].

    PubMed

    Yamamoto, Mariko; Nakadate, Hisaya; Iguchi, Umefumi; Masuda, Hiroshi; Sakai, Hirokazu; Ishiguro, Akira

    2013-03-01

    This report describes the successful management of neurosurgical procedures with continuous infusion of recombinant factor IX (rFIX). A 1-year-old boy with severe hemophilia B was administered prophylactic therapy with rFIX after intracranial bleeding. We found the enlargement of an arachnoid cyst in a follow-up CT scan. He underwent marsupialization of the cyst under the continuous infusion of rFIX. FIX levels were examined in our hospital and the rFIX infusion rate was adjusted in an attempt to keep FIX levels above 90% intraoperatively, and 70% until his 7th post-operative day. We studied the pharmacokinetic profile of rFIX and found a half-time of 25 hours and mean in vivo recovery of 0.69 IU/dl/IU/kg. Reconstituted rFIX also retained at least 95% activity after 72 hours at room temperature. This is the first report of the perioperative management of a child undergoing a neurosurgical procedure under the continuous infusion of rFIX in Japan. Further studies are required before the routine use of this product for continuous infusion.

  5. Keystroke Analysis: Reflections on Procedures and Measures

    ERIC Educational Resources Information Center

    Baaijen, Veerle M.; Galbraith, David; de Glopper, Kees

    2012-01-01

    Although keystroke logging promises to provide a valuable tool for writing research, it can often be difficult to relate logs to underlying processes. This article describes the procedures and measures that the authors developed to analyze a sample of 80 keystroke logs, with a view to achieving a better alignment between keystroke-logging measures…

  6. 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.

  7. Bayesian Factor Analysis When Only a Sample Covariance Matrix Is Available

    ERIC Educational Resources Information Center

    Hayashi, Kentaro; Arav, Marina

    2006-01-01

    In traditional factor analysis, the variance-covariance matrix or the correlation matrix has often been a form of inputting data. In contrast, in Bayesian factor analysis, the entire data set is typically required to compute the posterior estimates, such as Bayes factor loadings and Bayes unique variances. We propose a simple method for computing…

  8. Evaluation of Parallel Analysis Methods for Determining the Number of Factors

    ERIC Educational Resources Information Center

    Crawford, Aaron V.; Green, Samuel B.; Levy, Roy; Lo, Wen-Juo; Scott, Lietta; Svetina, Dubravka; Thompson, Marilyn S.

    2010-01-01

    Population and sample simulation approaches were used to compare the performance of parallel analysis using principal component analysis (PA-PCA) and parallel analysis using principal axis factoring (PA-PAF) to identify the number of underlying factors. Additionally, the accuracies of the mean eigenvalue and the 95th percentile eigenvalue criteria…

  9. Phrenic nerve injury after radiofrequency ablation of lung tumors: retrospective evaluation of the incidence and risk factors.

    PubMed

    Matsui, Yusuke; Hiraki, Takao; Gobara, Hideo; Uka, Mayu; Masaoka, Yoshihisa; Tada, Akihiro; Toyooka, Shinichi; Mitsuhashi, Toshiharu; Mimura, Hidefumi; Kanazawa, Susumu

    2012-06-01

    To retrospectively investigate the incidence of and risk factors for phrenic nerve injury after radiofrequency (RF) ablation of lung tumors. The study included 814 RF ablation procedures of lung tumors. To evaluate the development of phrenic nerve injury, chest radiographs obtained before and after the procedure were examined. Phrenic nerve injury was assumed to have developed if the diaphragmatic level was elevated after the procedure. To identify risk factors for phrenic nerve injury, multiple variables were compared between cases of phrenic nerve injury and randomly selected controls by using univariate analyses. Multivariate analysis was then performed to identify independent risk factors. Evaluation of phrenic nerve injury from chest radiographs was possible after 786 procedures. Evidence of phrenic nerve injury developed after 10 cases (1.3%). Univariate analysis revealed that larger tumor size (≥ 20 mm; P = .014), proximity of the phrenic nerve to the tumor (< 10 mm; P < .001), the use of larger electrodes (array diameter or noninsulated tip length ≥ 3 cm; P = .001), and higher maximum power applied during ablation (≥ 100 W; P < .001) were significantly associated with the development of phrenic nerve injury. Multivariate analysis demonstrated that the proximity of the phrenic nerve to the tumor (< 10 mm; P < .001) was a significant independent risk factor. The incidence of phrenic nerve injury after RF ablation was 1.3%. The proximity of the phrenic nerve to the tumor was an independent risk factor for phrenic nerve injury. Copyright © 2012 SIR. Published by Elsevier Inc. All rights reserved.

  10. Normalization of RNA-seq data using factor analysis of control genes or samples

    PubMed Central

    Risso, Davide; Ngai, John; Speed, Terence P.; Dudoit, Sandrine

    2015-01-01

    Normalization of RNA-seq data has proven essential to ensure accurate inference of expression levels. Here we show that usual normalization approaches mostly account for sequencing depth and fail to correct for library preparation and other more-complex unwanted effects. We evaluate the performance of the External RNA Control Consortium (ERCC) spike-in controls and investigate the possibility of using them directly for normalization. We show that the spike-ins are not reliable enough to be used in standard global-scaling or regression-based normalization procedures. We propose a normalization strategy, remove unwanted variation (RUV), that adjusts for nuisance technical effects by performing factor analysis on suitable sets of control genes (e.g., ERCC spike-ins) or samples (e.g., replicate libraries). Our approach leads to more-accurate estimates of expression fold-changes and tests of differential expression compared to state-of-the-art normalization methods. In particular, RUV promises to be valuable for large collaborative projects involving multiple labs, technicians, and/or platforms. PMID:25150836

  11. Sampling protocol, estimation, and analysis procedures for the down woody materials indicator of the FIA program

    Treesearch

    Christopher W. Woodall; Vicente J. Monleon

    2008-01-01

    The USDA Forest Service's Forest Inventory and Analysis program conducts an inventory of forests of the United States including down woody materials (DWM). In this report we provide the rationale and context for a national inventory of DWM, describe the components sampled, discuss the sampling protocol used and corresponding estimation procedures, and provide...

  12. Alternative Methods for Calculating Intercoder Reliability in Content Analysis: Kappa, Weighted Kappa and Agreement Charts Procedures.

    ERIC Educational Resources Information Center

    Kang, Namjun

    If content analysis is to satisfy the requirement of objectivity, measures and procedures must be reliable. Reliability is usually measured by the proportion of agreement of all categories identically coded by different coders. For such data to be empirically meaningful, a high degree of inter-coder reliability must be demonstrated. Researchers in…

  13. Application of Factor Analysis on the Financial Ratios of Indian Cement Industry and Validation of the Results by Cluster Analysis

    NASA Astrophysics Data System (ADS)

    De, Anupam; Bandyopadhyay, Gautam; Chakraborty, B. N.

    2010-10-01

    Financial ratio analysis is an important and commonly used tool in analyzing financial health of a firm. Quite a large number of financial ratios, which can be categorized in different groups, are used for this analysis. However, to reduce number of ratios to be used for financial analysis and regrouping them into different groups on basis of empirical evidence, Factor Analysis technique is being used successfully by different researches during the last three decades. In this study Factor Analysis has been applied over audited financial data of Indian cement companies for a period of 10 years. The sample companies are listed on the Stock Exchange India (BSE and NSE). Factor Analysis, conducted over 44 variables (financial ratios) grouped in 7 categories, resulted in 11 underlying categories (factors). Each factor is named in an appropriate manner considering the factor loads and constituent variables (ratios). Representative ratios are identified for each such factor. To validate the results of Factor Analysis and to reach final conclusion regarding the representative ratios, Cluster Analysis had been performed.

  14. 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

  15. 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…

  16. Percutaneous adhesiolysis procedures in the medicare population: analysis of utilization and growth patterns from 2000 to 2011.

    PubMed

    Manchikanti, Laxmaiah; Helm Ii, Standiford; Pampati, Vidyasagar; Racz, Gabor B

    2014-01-01

    Multiple reviews have shown that interventional techniques for chronic pain have increased dramatically over the years. Of these interventional techniques, both sacroiliac joint injections and facet joint interventions showed explosive growth, followed by epidural procedures. Percutaneous adhesiolysis procedures have not been assessed for their utilization patterns separately from epidural injections. An analysis of the utilization patterns of percutaneous adhesiolysis procedures in managing chronic low back pain in the Medicare population from 2000 to 2011. To assess the utilization and growth patterns of percutaneous adhesiolysis in managing chronic low back pain. The study was performed utilizing the Centers for Medicare and Medicaid Services (CMS) Physician Supplier Procedure Summary Master of Fee-For-Service (FFS) Data from 2000 to 2011. Percutaneous adhesiolysis procedures increased 47% with an annual growth rate of 3.6% in the FFS Medicare population from 2000 to 2011. These growth rates are significantly lower than the growth rates for sacroiliac joint injections (331%), facet joint interventions (308%), and epidural injections (130%), but substantially lower than lumbar transforaminal injections (665%) and lumbar facet joint neurolysis (544%). Study limitations include lack of inclusion of Medicare Advantage patients. In addition, the statewide data is based on claims which may include the contiguous or other states. Percutaneous adhesiolysis utilization increased moderately in Medicare beneficiaries from 2000 to 2011. Overall, there was an increase of 47% in the utilization of adhesiolysis procedures per 100,000 Medicare beneficiaries, with an annual geometric average increase of 3.6%.

  17. Centre characteristics and procedure-related factors have an impact on outcomes of allogeneic transplantation for patients with CLL: a retrospective analysis from the European Society for Blood and Marrow Transplantation (EBMT).

    PubMed

    Schetelig, Johannes; de Wreede, Liesbeth C; Andersen, Niels S; Moreno, Carol; van Gelder, Michel; Vitek, Antonin; Karas, Michal; Michallet, Mauricette; Machaczka, Maciej; Gramatzki, Martin; Beelen, Dietrich; Finke, Jürgen; Delgado, Julio; Volin, Liisa; Passweg, Jakob; Dreger, Peter; Schaap, Nicolaas; Wagner, Eva; Henseler, Anja; van Biezen, Anja; Bornhäuser, Martin; Iacobelli, Simona; Putter, Hein; Schönland, Stefan O; Kröger, Nicolaus

    2017-08-01

    The best approach for allogeneic haematopoietic stem cell transplantations (alloHCT) in patients with chronic lymphocytic leukaemia (CLL) is unknown. We therefore analysed the impact of procedure- and centre-related factors on 5-year event-free survival (EFS) in a large retrospective study. Data of 684 CLL patients who received a first alloHCT between 2000 and 2011 were analysed by multivariable Cox proportional hazards models with a frailty component to investigate unexplained centre heterogeneity. Five-year EFS of the whole cohort was 37% (95% confidence interval [CI], 34-42%). Larger numbers of CLL alloHCTs (hazard ratio [HR] 0·96, P = 0·002), certification of quality management (HR 0·7, P = 0·045) and a higher gross national income per capita (HR 0·4, P = 0·04) improved EFS. In vivo T-cell depletion (TCD) with alemtuzumab compared to no TCD (HR 1·5, P = 0·03), and a female donor compared to a male donor for a male patient (HR 1·4, P = 0·02) had a negative impact on EFS, but not non-myeloablative versus more intensive conditioning. After correcting for patient-, procedure- and centre-characteristics, significant variation in centre outcomes persisted. In conclusion, further research on the impact of centre and procedural characteristics is warranted. Non-myeloablative conditioning appears to be the preferable approach for patients with CLL. © 2017 John Wiley & Sons Ltd.

  18. Tennessee environmental procedures manual

    DOT National Transportation Integrated Search

    2007-04-16

    The Tennessee Environmental Procedures Manual (TEPM or manual) provides guidance for the preparation of environmental analysis and documentation for federally funded and state-funded transportation projects. /Abstract from report, p. I-1/

  19. 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…

  20. Surgical risk factors associated with lung transplantation.

    PubMed

    Paradela, M; González, D; Parente, I; Fernández, R; De La Torre, M M; Delgado, M; García, J A; Fieira, E; Bonhome, C; Maté, J M B

    2009-01-01

    Despite years of experience with lung transplantation, perioperative morbidity rates remain high. The objective of this study was to analyze our series of lung transplant recipients, seeking to identify possible intra- and postoperative risk factors associated with mortality. We performed a descriptive, retrospective study of 224 consecutive patients undergoing lung transplantation over a period of 112 months; we excluded retransplant procedures. We gathered details of the surgical procedure and postoperative period in the recovery unit. Univariate analysis using the chi-square test identified variables associated with the incidence of mortality. From 1999 to 2008, we performed 224 lung transplants, including 66% in men and 34% in women. Their overall mean age was 49.9 +/- 13.5 years. The conditions that led to transplantation were pulmonary fibrosis (38.4%); chronic obstructive pulmonary disease emphysema (29%); cystic fibrosis (10.7%); bronchiectasis (8.9%); pulmonary hypertension (3.1%); and other diseases (9.9%). A total of 124 (55.4%) patients underwent single and 100 (44.6%) received sequential bilateral lung transplantations. Surgical risk factors were identified in 51.3% of the cases, the most frequent being hemorrhage (25.3%), followed by severe pulmonary hypertension (14.7%) and cardiopulmonary bypass (12.1%). Greater perioperative mortality was detected among patients with surgical risk factors, namely, significantly related to cardiopulmonary bypass, pulmonary hypertension, and air leak. A higher frequency of surgical risk factors was observed among patients with bilateral lung transplantations and longer procedures, but they were not associated with greater perioperative mortality. Reoperation was necessary in 16 patients (7.2%), mainly owing to bleeding, it was not significantly related to mortality risk. The incidence of surgical risk factors in lung transplantation was high, especially in bilateral lung transplantations and prolonged procedures

  1. [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. Copyright © 2012 Asociación Colombiana de Psiquiatría. Publicado por Elsevier España. All rights reserved.

  2. [Hereditary heterozygous factor VII deficiency in patients undergoing surgery : Clinical relevance].

    PubMed

    Woehrle, D; Martinez, M; Bolliger, D

    2016-10-01

    A hereditary deficiency in coagulation factor VII (FVII) may affect the international normalized ratio (INR) value. However, FVII deficiency is occasionally associated with a tendency to bleed spontaneously. We hypothesized that perioperative substitution with coagulation factor concentrates might not be indicated in most patients. In this retrospective data analysis, we included all patients with hereditary heterozygous FVII deficiency who underwent surgical procedures at the University Hospital Basel between December 2010 and November 2015. In addition, by searching the literature, we identified publications reporting patients with FVII deficiency undergoing surgical procedures without perioperative substitution. We identified 22 patients undergoing 46 surgical procedures, resulting in a prevalence of 1:1500-2000. Coagulation factor concentrates were administered during the perioperative period in 15 procedures (33 %), whereas in the other 31 procedures (66 %), FVII deficiency was not substituted. No postoperative bleeding or thromboembolic events were reported. In addition, we found no differences in pre- and postoperative hemoglobin and coagulation parameters, with the exception of an improved postoperative INR value in the substituted group. In the literature review, we identified five publications, including 125 patients with FVII deficiency, undergoing 213 surgical procedures with no perioperative substitution. Preoperative substitution using coagulation factor concentrates does not seem to be mandatory in patients with an FVII level ≥15 %. For decision-making on preoperative substitution, patient history of an increased tendency to bleed may be more important than the FVII level or increased INR value.

  3. Analysis of Factors Influencing Creative Personality of Elementary School Students

    ERIC Educational Resources Information Center

    Park, Jongman; Kim, Minkee; Jang, Shinho

    2017-01-01

    This quantitative research examined factors that affect elementary students' creativity and how those factors correlate. Aiming to identify significant factors that affect creativity and to clarify the relationship between these factors by path analysis, this research was designed to be a stepping stone for creativity enhancement studies. Data…

  4. Generalized five-dimensional dynamic and spectral factor analysis

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

    El Fakhri, Georges; Sitek, Arkadiusz; Zimmerman, Robert E.

    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 thatmore » 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

  5. A procedure for analysis of guyline tension.

    Treesearch

    Ward W. Carson; Jens E. Jorgensen; Stephen E. Reutebuch; William J. Bramwell

    1982-01-01

    Most cable logging operations use a spar held in place near the landing by a system of guylines and anchors. Safety and economic considerations require that overloads be avoided and that the spar remain stable. This paper presents a procedure and a computer program to estimate the guyline and anchor loads on a particular system configuration by a specific set of...

  6. An analysis of contingency statements in a DRO procedure: A case report.

    PubMed

    Gerow, Stephanie; Rispoli, Mandy; Boles, Margot B; Neely, Leslie C

    2015-06-01

    To examine latency to criterion for reduction of challenging behaviour with and without stating a contingency statement immediately prior to a DRO procedure. An ABAC design in which A was baseline, B was used to evaluate the efficacy of a DRO procedure, and C was used to evaluate the efficacy of a DRO procedure with a contingency statement. The DRO with the contingency statement intervention was associated with a shorter latency to behaviour change than the DRO procedure without the contingency statement. These preliminary findings from this case study highlight the importance of examining the efficiency of behaviour change procedures. Directions for future research are provided.

  7. 49 CFR Appendix D to Part 172 - Rail Risk Analysis Factors

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 2 2011-10-01 2011-10-01 false Rail Risk Analysis Factors D Appendix D to Part... REQUIREMENTS, AND SECURITY PLANS Pt. 172, App. D Appendix D to Part 172—Rail Risk Analysis Factors A. This... safety and security risk analyses required by § 172.820. The risk analysis to be performed may be...

  8. 49 CFR Appendix D to Part 172 - Rail Risk Analysis Factors

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 2 2010-10-01 2010-10-01 false Rail Risk Analysis Factors D Appendix D to Part... REQUIREMENTS, AND SECURITY PLANS Pt. 172, App. D Appendix D to Part 172—Rail Risk Analysis Factors A. This... safety and security risk analyses required by § 172.820. The risk analysis to be performed may be...

  9. [Procedural learning and anxiolytic effects: electroencephalographic, motor and attentional measures].

    PubMed

    Portella, Claudio Elidio; Silva, Julio Guilherme; Bastos, Victor Hugo; Machado, Dionis; Cunha, Marlo; Cagy, Maurício; Basile, Luis; Piedade, Roberto; Ribeiro, Pedro

    2006-06-01

    The objective of the present study was to evaluate attentional, motor and electroencephalographic (EEG) parameters during a procedural task when subjects have ingested 6 mg of bromazepam. The sample consisted of 26 healthy subjects, male or female, between 19 and 36 years of age. The control (placebo) and experimental (bromazepam 6 mg) groups were submitted to a typewriting task in a randomized, double-blind design. The findings did not show significant differences in attentional and motor measures between groups. Coherence measures (qEEG) were evaluated between scalp regions, in theta, alpha and beta bands. A first analysis revealed a main effect for condition (Anova 2-way--condition versus blocks). A second Anova 2-way (condition versus scalp regions) showed a main effect for both factors. The coherence measure was not a sensitive tool at demonstrating differences between cortical areas as a function of procedural learning.

  10. Examining evolving performance on the Force Concept Inventory using factor analysis

    NASA Astrophysics Data System (ADS)

    Semak, M. R.; Dietz, R. D.; Pearson, R. H.; Willis, C. W.

    2017-06-01

    The application of factor analysis to the Force Concept Inventory (FCI) has proven to be problematic. Some studies have suggested that factor analysis of test results serves as a helpful tool in assessing the recognition of Newtonian concepts by students. Other work has produced at best ambiguous results. For the FCI administered as a pre- and post-test, we see factor analysis as a tool by which the changes in conceptual associations made by our students may be gauged given the evolution of their response patterns. This analysis allows us to identify and track conceptual linkages, affording us insight as to how our students have matured due to instruction. We report on our analysis of 427 pre- and post-tests. The factor models for the pre- and post-tests are explored and compared along with the methodology by which these models were fit to the data. The post-test factor pattern is more aligned with an expert's interpretation of the questions' content, as it allows for a more readily identifiable relationship between factors and physical concepts. We discuss this evolution in the context of approaching the characteristics of an expert with force concepts. Also, we find that certain test items do not significantly contribute to the pre- or post-test factor models and attempt explanations as to why this is so. This may suggest that such questions may not be effective in probing the conceptual understanding of our students.

  11. Academic status does not affect outcome following complex hepato-pancreato-biliary procedures.

    PubMed

    Altieri, Maria S; Yang, Jie; Groves, Donald; Yin, Donglei; Cagino, Kristen; Talamini, Mark; Pryor, Aurora

    2018-05-01

    There is a growing debate regarding outcomes following complex hepato-pancreato-biliary (HPB) procedures. The purpose of our study is to examine if facility type has any impact on complications, readmission rates, emergency department (ED) visit rates, and length of stay (LOS) for patients undergoing HPB surgery. The SPARCS administrative database was used to identify patients undergoing complex HPB procedures between 2012 and 2014 in New York. Univariate generalized linear mixed models were fit to estimate the marginal association between outcomes such as overall/severe complication rates, 30-day and 1-year readmission rates, 30-day and 1-year ED-visit rates, and potential risk factors. Univariate linear mixed models were used to estimate the marginal association between possible risk factors and LOS. Facility type, as well as any variables found to be significant in our univariate analysis (p = 0.05), was further included in the multivariable regression models. There were 4122 complex HPB procedures performed. Academic facilities were more likely to have a higher hospital volume (p < 0001). Surgery at academic facilities were less likely to have coexisting comorbidities; however, they were more likely to have metastatic cancer and/or liver disease (p = 0.0114, < 0. 0001, and = 0.0299, respectively). Postoperatively, patients at non-academic facilities experienced higher overall complication rates, and higher severe complication rates, when compared to those at academic facilities (p < 0.0001 and = 0.0018, respectively). Further analysis via adjustment for possible confounding factors, however, revealed no significant difference in the risk of severe complications between the two facility types. Such adjustment also demonstrated higher 30-day readmission risk in patients who underwent their surgery at an academic facility. No significant difference was found when comparing the outcomes of academic and non-academic facilities, after adjusting

  12. 76 FR 21239 - Revision of Voting Rights Procedures

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-15

    ... both the Attorney General and the district court undertake, i.e., deciding whether the change complies..., or procedure affecting voting, not only a practice or procedure. Section 51.57(e) Relevant Factors...'' as synonyms for each other. See, e.g., Harper v. Virginia State Board of Elections, 383 U.S. 663, 667...

  13. Cytological preparations for molecular analysis: A review of technical procedures, advantages and limitations for referring samples for testing.

    PubMed

    da Cunha Santos, G; Saieg, M A; Troncone, G; Zeppa, P

    2018-04-01

    Minimally invasive procedures such as endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) must yield not only good quality and quantity of material for morphological assessment, but also an adequate sample for analysis of molecular markers to guide patients to appropriate targeted therapies. In this context, cytopathologists worldwide should be familiar with minimum requirements for refereeing cytological samples for testing. The present manuscript is a review with comprehensive description of the content of the workshop entitled Cytological preparations for molecular analysis: pre-analytical issues for EBUS TBNA, presented at the 40th European Congress of Cytopathology in Liverpool, UK. The present review emphasises the advantages and limitations of different types of cytology substrates used for molecular analysis such as archival smears, liquid-based preparations, archival cytospin preparations and FTA (Flinders Technology Associates) cards, as well as their technical requirements/features. These various types of cytological specimens can be successfully used for an extensive array of molecular studies, but the quality and quantity of extracted nucleic acids rely directly on adequate pre-analytical assessment of those samples. In this setting, cytopathologists must not only be familiar with the different types of specimens and associated technical procedures, but also correctly handle the material provided by minimally invasive procedures, ensuring that there is sufficient amount of material for a precise diagnosis and correct management of the patient through personalised care. © 2018 John Wiley & Sons Ltd.

  14. The effects of predictor method factors on selection outcomes: A modular approach to personnel selection procedures.

    PubMed

    Lievens, Filip; Sackett, Paul R

    2017-01-01

    Past reviews and meta-analyses typically conceptualized and examined selection procedures as holistic entities. We draw on the product design literature to propose a modular approach as a complementary perspective to conceptualizing selection procedures. A modular approach means that a product is broken down into its key underlying components. Therefore, we start by presenting a modular framework that identifies the important measurement components of selection procedures. Next, we adopt this modular lens for reviewing the available evidence regarding each of these components in terms of affecting validity, subgroup differences, and applicant perceptions, as well as for identifying new research directions. As a complement to the historical focus on holistic selection procedures, we posit that the theoretical contributions of a modular approach include improved insight into the isolated workings of the different components underlying selection procedures and greater theoretical connectivity among different selection procedures and their literatures. We also outline how organizations can put a modular approach into operation to increase the variety in selection procedures and to enhance the flexibility in designing them. Overall, we believe that a modular perspective on selection procedures will provide the impetus for programmatic and theory-driven research on the different measurement components of selection procedures. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  15. Red blood cell transfusion probability and associated costs in neurosurgical procedures.

    PubMed

    Barth, Martin; Weiss, Christel; Schmieder, Kirsten

    2018-03-20

    The extent of red blood cell units (RBC) needed for different neurosurgical procedures and the time point of their administration are widely unknown, which results in generously cross-matching prior to surgery. However, RBC are increasingly requested in the aging western populations, and blood donations are significantly reduced. Therefore, the knowledge of the extent and time point of administration of RBC is of major importance. This is a retrospective single center analysis. The incidence of RBC transfusion during surgery or within 48 h after surgery was analyzed for all neurosurgical patients within 3 years. Costs for cross-matched and transfused RBC were calculated and risk factors for RBC transfusion analyzed. The risk of intraoperative RBC administration was low for spinal and intracranial tumor resections (1.87%) and exceeded 10% only in spinal fusion procedures. This was dependent on the number of fused segments with an intraoperative transfusion risk of > 12.5% with fusion of more than three levels. Multiple logistic regression analysis showed a significantly increased risk for RBC transfusion for female gender (p = 0.006; OR 1.655), higher age (N = 4812; p < 0.0001; OR 1.028), and number of fused segments (N = 737; p < 0.0001; OR 1.433). Annual costs for cross-matching were 783,820.88 USD and for intraoperative RBC administration 121,322.13 USD. Neurosurgical procedures are associated with a low number of RBC needed intraoperatively. Only elective spine fusion procedures with ≥ 3 levels involved and AVM resections seem to require cross-matching of RBC. The present data may allow changing the preoperative algorithm of RBC cross-matching in neurosurgical procedures and help to save resources and costs.

  16. Analysis of plant gums and saccharide materials in paint samples: comparison of GC-MS analytical procedures and databases

    PubMed Central

    2012-01-01

    Background Saccharide materials have been used for centuries as binding media, to paint, write and illuminate manuscripts and to apply metallic leaf decorations. Although the technical literature often reports on the use of plant gums as binders, actually several other saccharide materials can be encountered in paint samples, not only as major binders, but also as additives. In the literature, there are a variety of analytical procedures that utilize GC-MS to characterize saccharide materials in paint samples, however the chromatographic profiles are often extremely different and it is impossible to compare them and reliably identify the paint binder. Results This paper presents a comparison between two different analytical procedures based on GC-MS for the analysis of saccharide materials in works-of-art. The research presented here evaluates the influence of the analytical procedure used, and how it impacts the sugar profiles obtained from the analysis of paint samples that contain saccharide materials. The procedures have been developed, optimised and systematically used to characterise plant gums at the Getty Conservation Institute in Los Angeles, USA (GCI) and the Department of Chemistry and Industrial Chemistry of the University of Pisa, Italy (DCCI). The main steps of the analytical procedures and their optimisation are discussed. Conclusions The results presented highlight that the two methods give comparable sugar profiles, whether the samples analysed are simple raw materials, pigmented and unpigmented paint replicas, or paint samples collected from hundreds of centuries old polychrome art objects. A common database of sugar profiles of reference materials commonly found in paint samples was thus compiled. The database presents data also from those materials that only contain a minor saccharide fraction. This database highlights how many sources of saccharides can be found in a paint sample, representing an important step forward in the problem of

  17. Analysis of plant gums and saccharide materials in paint samples: comparison of GC-MS analytical procedures and databases.

    PubMed

    Lluveras-Tenorio, Anna; Mazurek, Joy; Restivo, Annalaura; Colombini, Maria Perla; Bonaduce, Ilaria

    2012-10-10

    Saccharide materials have been used for centuries as binding media, to paint, write and illuminate manuscripts and to apply metallic leaf decorations. Although the technical literature often reports on the use of plant gums as binders, actually several other saccharide materials can be encountered in paint samples, not only as major binders, but also as additives. In the literature, there are a variety of analytical procedures that utilize GC-MS to characterize saccharide materials in paint samples, however the chromatographic profiles are often extremely different and it is impossible to compare them and reliably identify the paint binder. This paper presents a comparison between two different analytical procedures based on GC-MS for the analysis of saccharide materials in works-of-art. The research presented here evaluates the influence of the analytical procedure used, and how it impacts the sugar profiles obtained from the analysis of paint samples that contain saccharide materials. The procedures have been developed, optimised and systematically used to characterise plant gums at the Getty Conservation Institute in Los Angeles, USA (GCI) and the Department of Chemistry and Industrial Chemistry of the University of Pisa, Italy (DCCI). The main steps of the analytical procedures and their optimisation are discussed. The results presented highlight that the two methods give comparable sugar profiles, whether the samples analysed are simple raw materials, pigmented and unpigmented paint replicas, or paint samples collected from hundreds of centuries old polychrome art objects. A common database of sugar profiles of reference materials commonly found in paint samples was thus compiled. The database presents data also from those materials that only contain a minor saccharide fraction. This database highlights how many sources of saccharides can be found in a paint sample, representing an important step forward in the problem of identifying polysaccharide binders in

  18. Ultra-high performance supercritical fluid chromatography-mass spectrometry procedure for analysis of monosaccharides from plant gum binders.

    PubMed

    Pauk, Volodymyr; Pluháček, Tomáš; Havlíček, Vladimír; Lemr, Karel

    2017-10-09

    The ultra-high performance supercritical fluid chromatography-mass spectrometry (UHPSFC/MS) procedure for analysis of native monosaccharides was developed. Chromatographic conditions were investigated to separate a mixture of four hexoses, three pentoses, two deoxyhexoses and two uronic acids. Increasing water content in methanol modifier to 5% and formic acid to 4% improved peak shapes of neutral monosaccharides and allowed complete elution of highly polar uronic acids in a single run. An Acquity HSS C18SB column outperformed other three tested stationary phases (BEH (silica), BEH 2-ethylpyridine, CSH Fluoro-Phenyl) in terms of separation of isomers and analysis time (4.5 min). Limits of detection were in the range 0.01-0.12 ng μL -1 . Owing to separation of anomers, identification of critical pairs (arabinose-xylose and glucose-galactose) was possible. Feasibility of the new method was demonstrated on plant-derived polysaccharide binders. Samples of watercolor paints, painted paper and three plant gums widely encountered in painting media (Arabic, cherry and tragacanth) were decomposed prior the analysis by microwave-assisted hydrolysis at 40 bar initial pressure using 2 mol L -1 trifluoroacetic acid. Among tested temperatures, 120 °C ensured appropriate hydrolysis efficiency for different types of gum and avoided excessive degradation of labile monosaccharides. Procedure recovery tested on gum Arabic was 101% with an RSD below 8%. Aqueous hydrolysates containing monosaccharides in different ratios specific to each type of plant gum were diluted or analyzed directly. Filtration of samples before hydrolysis reduced interferences from a paper support and identification of gum Arabic in watercolor-painted paper samples was demonstrated. Successful identification of pure gum Arabic was confirmed for sample quantities as little as 1 μg. Two classification approaches were compared and principal component analysis was superior to analysis based on peak area

  19. An efficient numerical procedure for thermohydrodynamic analysis of cavitating bearings

    NASA Technical Reports Server (NTRS)

    Vijayaraghavan, D.

    1995-01-01

    An efficient and accurate numerical procedure to determine the thermo-hydrodynamic performance of cavitating bearings is described. This procedure is based on the earlier development of Elrod for lubricating films, in which the properties across the film thickness are determined at Lobatto points and their distributions are expressed by collocated polynomials. The cavitated regions and their boundaries are rigorously treated. Thermal boundary conditions at the surfaces, including heat dissipation through the metal to the ambient, are incorporated. Numerical examples are presented comparing the predictions using this procedure with earlier theoretical predictions and experimental data. With a few points across the film thickness and across the journal and the bearing in the radial direction, the temperature profile is very well predicted.

  20. Error analysis for intrinsic quality factor measurement in superconducting radio frequency resonators

    DOE PAGES

    Melnychuk, O.; Grassellino, A.; Romanenko, A.

    2014-12-19

    In this paper, we discuss error analysis for intrinsic quality factor (Q₀) and accelerating gradient (E acc ) measurements in superconducting radio frequency (SRF) resonators. The analysis is applicable for cavity performance tests that are routinely performed at SRF facilities worldwide. We review the sources of uncertainties along with the assumptions on their correlations and present uncertainty calculations with a more complete procedure for treatment of correlations than in previous publications [T. Powers, in Proceedings of the 12th Workshop on RF Superconductivity, SuP02 (Elsevier, 2005), pp. 24–27]. Applying this approach to cavity data collected at Vertical Test Stand facility atmore » Fermilab, we estimated total uncertainty for both Q₀ and E acc to be at the level of approximately 4% for input coupler coupling parameter β₁ in the [0.5, 2.5] range. Above 2.5 (below 0.5) Q₀ uncertainty increases (decreases) with β₁ whereas E acc uncertainty, in contrast with results in Powers [in Proceedings of the 12th Workshop on RF Superconductivity, SuP02 (Elsevier, 2005), pp. 24–27], is independent of β₁. Overall, our estimated Q₀ uncertainty is approximately half as large as that in Powers [in Proceedings of the 12th Workshop on RF Superconductivity, SuP02 (Elsevier, 2005), pp. 24–27].« less

  1. Risk Factors for Urinary Tract Infections in Cardiac Surgical Patients

    PubMed Central

    Gillen, Jacob R.; Isbell, James M.; Michaels, Alex D.; Lau, Christine L.

    2015-01-01

    Abstract Background: Risk factors for catheter-associated urinary tract infections (CAUTIs) in patients undergoing non-cardiac surgical procedures have been well documented. However, the variables associated with CAUTIs in the cardiac surgical population have not been clearly defined. Therefore, the purpose of this study was to investigate risk factors associated with CAUTIs in patients undergoing cardiac procedures. Methods: All patients undergoing cardiac surgery at a single institution from 2006 through 2012 (4,883 patients) were reviewed. Patients with U.S. Centers for Disease Control (CDC) criteria for CAUTI were identified from the hospital's Quality Assessment database. Pre-operative, operative, and post-operative patient factors were evaluated. Univariate and multivariable analyses were used to identify significant correlations between perioperative characteristics and CAUTIs. Results: There were 55 (1.1%) documented CAUTIs in the study population. On univariate analysis, older age, female gender, diabetes mellitus, cardiogenic shock, urgent or emergent operation, packed red blood cell (PRBC) units transfused, and intensive care unit length of stay (ICU LOS) were all significantly associated with CAUTI [p<0.05]. On multivariable logistic regression, older age, female gender, diabetes mellitus, and ICU LOS remained significantly associated with CAUTI. Additionally, there was a significant association between CAUTI and 30-d mortality on univariate analysis. However, when controlling for common predictors of operative mortality on multivariable analysis, CAUTI was no longer associated with mortality. Conclusions: There are several identifiable risk factors for CAUTI in patients undergoing cardiac procedures. CAUTI is not independently associated with increased mortality, but it does serve as a marker of sicker patients more likely to die from other comorbidities or complications. Therefore, awareness of the high-risk nature of these patients should lead to

  2. Risk Factors for Urinary Tract Infections in Cardiac Surgical Patients.

    PubMed

    Gillen, Jacob R; Isbell, James M; Michaels, Alex D; Lau, Christine L; Sawyer, Robert G

    2015-10-01

    Risk factors for catheter-associated urinary tract infections (CAUTIs) in patients undergoing non-cardiac surgical procedures have been well documented. However, the variables associated with CAUTIs in the cardiac surgical population have not been clearly defined. Therefore, the purpose of this study was to investigate risk factors associated with CAUTIs in patients undergoing cardiac procedures. All patients undergoing cardiac surgery at a single institution from 2006 through 2012 (4,883 patients) were reviewed. Patients with U.S. Centers for Disease Control (CDC) criteria for CAUTI were identified from the hospital's Quality Assessment database. Pre-operative, operative, and post-operative patient factors were evaluated. Univariate and multivariable analyses were used to identify significant correlations between perioperative characteristics and CAUTIs. There were 55 (1.1%) documented CAUTIs in the study population. On univariate analysis, older age, female gender, diabetes mellitus, cardiogenic shock, urgent or emergent operation, packed red blood cell (PRBC) units transfused, and intensive care unit length of stay (ICU LOS) were all significantly associated with CAUTI [p<0.05]. On multivariable logistic regression, older age, female gender, diabetes mellitus, and ICU LOS remained significantly associated with CAUTI. Additionally, there was a significant association between CAUTI and 30-d mortality on univariate analysis. However, when controlling for common predictors of operative mortality on multivariable analysis, CAUTI was no longer associated with mortality. There are several identifiable risk factors for CAUTI in patients undergoing cardiac procedures. CAUTI is not independently associated with increased mortality, but it does serve as a marker of sicker patients more likely to die from other comorbidities or complications. Therefore, awareness of the high-risk nature of these patients should lead to increased diligence and may help to improve peri

  3. The environmental analysis of helicopter operations by Federal agencies: Current procedures and research needs

    NASA Technical Reports Server (NTRS)

    Smith, C. C.; Warner, D. B.; Dajani, J. S.

    1977-01-01

    The technical, economic, and environmental problems restricting commercial helicopter passenger operations are reviewed. The key considerations for effective assessment procedures are outlined and a preliminary model for the environmental analysis of helicopters is developed. It is recommended that this model, or some similar approach, be used as a common base for the development of comprehensive environmental assessment methods for each of the federal agencies concerned with helicopters. A description of the critical environmental research issues applicable to helicopters is also presented.

  4. Dual-Tracer PET Using Generalized Factor Analysis of Dynamic Sequences

    PubMed Central

    Fakhri, Georges El; Trott, Cathryn M.; Sitek, Arkadiusz; Bonab, Ali; Alpert, Nathaniel M.

    2013-01-01

    Purpose With single-photon emission computed tomography, simultaneous imaging of two physiological processes relies on discrimination of the energy of the emitted gamma rays, whereas the application of dual-tracer imaging to positron emission tomography (PET) imaging has been limited by the characteristic 511-keV emissions. Procedures To address this limitation, we developed a novel approach based on generalized factor analysis of dynamic sequences (GFADS) that exploits spatio-temporal differences between radiotracers and applied it to near-simultaneous imaging of 2-deoxy-2-[18F]fluoro-D-glucose (FDG) (brain metabolism) and 11C-raclopride (D2) with simulated human data and experimental rhesus monkey data. We show theoretically and verify by simulation and measurement that GFADS can separate FDG and raclopride measurements that are made nearly simultaneously. Results The theoretical development shows that GFADS can decompose the studies at several levels: (1) It decomposes the FDG and raclopride study so that they can be analyzed as though they were obtained separately. (2) If additional physiologic/anatomic constraints can be imposed, further decomposition is possible. (3) For the example of raclopride, specific and nonspecific binding can be determined on a pixel-by-pixel basis. We found good agreement between the estimated GFADS factors and the simulated ground truth time activity curves (TACs), and between the GFADS factor images and the corresponding ground truth activity distributions with errors less than 7.3±1.3 %. Biases in estimation of specific D2 binding and relative metabolism activity were within 5.9±3.6 % compared to the ground truth values. We also evaluated our approach in simultaneous dual-isotope brain PET studies in a rhesus monkey and obtained accuracy of better than 6 % in a mid-striatal volume, for striatal activity estimation. Conclusions Dynamic image sequences acquired following near-simultaneous injection of two PET radiopharmaceuticals

  5. Testing all six person-oriented principles in dynamic factor analysis.

    PubMed

    Molenaar, Peter C M

    2010-05-01

    All six person-oriented principles identified by Sterba and Bauer's Keynote Article can be tested by means of dynamic factor analysis in its current form. In particular, it is shown how complex interactions and interindividual differences/intraindividual change can be tested in this way. In addition, the necessity to use single-subject methods in the analysis of developmental processes is emphasized, and attention is drawn to the possibility to optimally treat developmental psychopathology by means of new computational techniques that can be integrated with dynamic factor analysis.

  6. Procedure for analysis and design of weaving sections : volume 1, research findings and development of techniques for application.

    DOT National Transportation Integrated Search

    1983-12-01

    This research was performed to complete and advance the status of recently developed : procedures for analysis and design of weaving sections (known as the Leisch method and-initially published in the 1979 issue of ITE Journal). The objective was to ...

  7. Exploratory factor analysis of borderline personality disorder criteria in hospitalized adolescents.

    PubMed

    Becker, Daniel F; McGlashan, Thomas H; Grilo, Carlos M

    2006-01-01

    The authors examined the factor structure of borderline personality disorder (BPD) in hospitalized adolescents and also sought to add to the theoretical and clinical understanding of any homogeneous components by determining whether they may be related to specific forms of Axis I pathology. Subjects were 123 adolescent inpatients, who were reliably assessed with structured diagnostic interviews for Diagnostic and Statistical Manual of Mental Disorders, Revised Third Edition Axes I and II disorders. Exploratory factor analysis identified BPD components, and logistic regression analyses tested whether these components were predictive of specific Axis I disorders. Factor analysis revealed a 4-factor solution that accounted for 67.0% of the variance. Factor 1 ("suicidal threats or gestures" and "emptiness or boredom") predicted depressive disorders and alcohol use disorders. Factor 2 ("affective instability," "uncontrolled anger," and "identity disturbance") predicted anxiety disorders and oppositional defiant disorder. Factor 3 ("unstable relationships" and "abandonment fears") predicted only anxiety disorders. Factor 4 ("impulsiveness" and "identity disturbance") predicted conduct disorder and substance use disorders. Exploratory factor analysis of BPD criteria in adolescent inpatients revealed 4 BPD factors that appear to differ from those reported for similar studies of adults. The factors represent components of self-negation, irritability, poorly modulated relationships, and impulsivity--each of which is associated with characteristic Axis I pathology. These findings shed light on the nature of BPD in adolescents and may also have implications for treatment.

  8. 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. © 2014 John Wiley & Sons Ltd.

  9. Current good manufacturing practices, quality control procedures, quality factors, notification requirements, and records and reports, for infant formula. Final rule.

    PubMed

    2014-06-10

    The Food and Drug Administration (FDA or we) is issuing a final rule that adopts, with some modifications, the interim final rule (IFR) entitled "Current Good Manufacturing Practices, Quality Control Procedures, Quality Factors, Notification Requirements, and Records and Reports, for Infant Formula'' (February 10, 2014). This final rule affirms the IFR's changes to FDA's regulations and provides additional modifications and clarifications. The final rule also responds to certain comments submitted in response to the request for comments in the IFR.

  10. Factor analysis of an instrument to measure the impact of disease on daily life.

    PubMed

    Pedrosa, Rafaela Batista Dos Santos; Rodrigues, Roberta Cunha Matheus; Padilha, Kátia Melissa; Gallani, Maria Cecília Bueno Jayme; Alexandre, Neusa Maria Costa

    2016-01-01

    to verify the structure of factors of an instrument to measure the Heart Valve Disease Impact on Daily Life (IDCV) when applied to coronary artery disease patients. the study included 153 coronary artery disease patients undergoing outpatient follow-up care. The IDCV structure of factors was initially assessed by means of confirmatory factor analysis and, subsequently, by exploratory factor analysis. The Varimax rotation method was used to estimate the main components of analysis, eigenvalues greater than one for extraction of factors, and factor loading greater than 0.40 for selection of items. Internal consistency was estimated using Cronbach's alpha coefficient. confirmatory factor analysis did not confirm the original structure of factors of the IDCV. Exploratory factor analysis showed three dimensions, which together explained 78% of the measurement variance. future studies with expansion of case selection are necessary to confirm the IDCV new structure of factors.

  11. Biomechanical analysis of the upper thoracic spine after decompressive procedures.

    PubMed

    Healy, Andrew T; Lubelski, Daniel; Mageswaran, Prasath; Bhowmick, Deb A; Bartsch, Adam J; Benzel, Edward C; Mroz, Thomas E

    2014-06-01

    Decompressive procedures such as laminectomy, facetectomy, and costotransversectomy are routinely performed for various pathologies in the thoracic spine. The thoracic spine is unique, in part, because of the sternocostovertebral articulations that provide additional strength to the region relative to the cervical and lumbar spines. During decompressive surgeries, stability is compromised at a presently unknown point. To evaluate thoracic spinal stability after common surgical decompressive procedures in thoracic spines with intact sternocostovertebral articulations. Biomechanical cadaveric study. Fresh-frozen human cadaveric spine specimens with intact rib cages, C7-L1 (n=9), were used. An industrial robot tested all spines in axial rotation (AR), lateral bending (LB), and flexion-extension (FE) by applying pure moments (±5 Nm). The specimens were first tested in their intact state and then tested after each of the following sequential surgical decompressive procedures at T4-T5 consisting of laminectomy; unilateral facetectomy; unilateral costotransversectomy, and subsequently instrumented fusion from T3-T7. We found that in all three planes of motion, the sequential decompressive procedures caused no statistically significant change in motion between T3-T7 or T1-T12 when compared with intact. In comparing between intact and instrumented specimens, our study found that instrumentation reduced global range of motion (ROM) between T1-T12 by 16.3% (p=.001), 12% (p=.002), and 18.4% (p=.0004) for AR, FE, and LB, respectively. Age showed a negative correlation with motion in FE (r = -0.78, p=.01) and AR (r=-0.7, p=.04). Thoracic spine stability was not significantly affected by sequential decompressive procedures in thoracic segments at the level of the true ribs in all three planes of motion in intact thoracic specimens. Age appeared to negatively correlate with ROM of the specimen. Our study suggests that thoracic spinal stability is maintained immediately after

  12. DOSE COEFFICIENTS FOR LIVER CHEMOEMBOLISATION PROCEDURES USING MONTE CARLO CODE.

    PubMed

    Karavasilis, E; Dimitriadis, A; Gonis, H; Pappas, P; Georgiou, E; Yakoumakis, E

    2016-12-01

    The aim of the present study is the estimation of radiation burden during liver chemoembolisation procedures. Organ dose and effective dose conversion factors, normalised to dose-area product (DAP), were estimated for chemoembolisation procedures using a Monte Carlo transport code in conjunction with an adult mathematical phantom. Exposure data from 32 patients were used to determine the exposure projections for the simulations. Equivalent organ (H T ) and effective (E) doses were estimated using individual DAP values. The organs receiving the highest amount of doses during these exams were lumbar spine, liver and kidneys. The mean effective dose conversion factor was 1.4 Sv Gy -1 m -2 Dose conversion factors can be useful for patient-specific radiation burden during chemoembolisation procedures. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  13. Improved Variable Selection Algorithm Using a LASSO-Type Penalty, with an Application to Assessing Hepatitis B Infection Relevant Factors in Community Residents

    PubMed Central

    Guo, Pi; Zeng, Fangfang; Hu, Xiaomin; Zhang, Dingmei; Zhu, Shuming; Deng, Yu; Hao, Yuantao

    2015-01-01

    Objectives In epidemiological studies, it is important to identify independent associations between collective exposures and a health outcome. The current stepwise selection technique ignores stochastic errors and suffers from a lack of stability. The alternative LASSO-penalized regression model can be applied to detect significant predictors from a pool of candidate variables. However, this technique is prone to false positives and tends to create excessive biases. It remains challenging to develop robust variable selection methods and enhance predictability. Material and methods Two improved algorithms denoted the two-stage hybrid and bootstrap ranking procedures, both using a LASSO-type penalty, were developed for epidemiological association analysis. The performance of the proposed procedures and other methods including conventional LASSO, Bolasso, stepwise and stability selection models were evaluated using intensive simulation. In addition, methods were compared by using an empirical analysis based on large-scale survey data of hepatitis B infection-relevant factors among Guangdong residents. Results The proposed procedures produced comparable or less biased selection results when compared to conventional variable selection models. In total, the two newly proposed procedures were stable with respect to various scenarios of simulation, demonstrating a higher power and a lower false positive rate during variable selection than the compared methods. In empirical analysis, the proposed procedures yielding a sparse set of hepatitis B infection-relevant factors gave the best predictive performance and showed that the procedures were able to select a more stringent set of factors. The individual history of hepatitis B vaccination, family and individual history of hepatitis B infection were associated with hepatitis B infection in the studied residents according to the proposed procedures. Conclusions The newly proposed procedures improve the identification of

  14. 43 CFR 10010.48 - Decision-making procedures.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... in its formal decision-making procedures provisions for consideration of environmental factors and... the environmental impacts of the entire range of alternatives described in any relevant environmental...

  15. 43 CFR 10010.48 - Decision-making procedures.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... in its formal decision-making procedures provisions for consideration of environmental factors and... the environmental impacts of the entire range of alternatives described in any relevant environmental...

  16. 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.

  17. Tensor-Dictionary Learning with Deep Kruskal-Factor Analysis

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

    Stevens, Andrew J.; Pu, Yunchen; Sun, Yannan

    We introduce new dictionary learning methods for tensor-variate data of any order. We represent each data item as a sum of Kruskal decomposed dictionary atoms within the framework of beta-process factor analysis (BPFA). Our model is nonparametric and can infer the tensor-rank of each dictionary atom. This Kruskal-Factor Analysis (KFA) is a natural generalization of BPFA. We also extend KFA to a deep convolutional setting and develop online learning methods. We test our approach on image processing and classification tasks achieving state of the art results for 2D & 3D inpainting and Caltech 101. The experiments also show that atom-rankmore » impacts both overcompleteness and sparsity.« less

  18. Reoperations within 48 hours following 7942 pediatric neurosurgery procedures.

    PubMed

    Roy, Anil K; Chu, Jason; Bozeman, Caroline; Sarda, Samir; Sawvel, Michael; Chern, Joshua J

    2017-06-01

    OBJECTIVE Various indicators are used to evaluate the quality of care delivered by surgical services, one of which is early reoperation rate. The indications and rate of reoperations within a 48-hour time period have not been previously reported for pediatric neurosurgery. METHODS Between May 1, 2009, and December 30, 2014, 7942 surgeries were performed by the pediatric neurosurgery service in the operating rooms at a single institution. Demographic, socioeconomic, and clinical characteristics associated with each of the operations were prospectively collected. The procedures were grouped into 31 categories based on the nature of the procedure and underlying diseases. Reoperations within 48 hours at the conclusion of the index surgery were reviewed to determine whether the reoperation was planned or unplanned. Multivariate logistic regression was employed to analyze risk factors associated with unplanned reoperations. RESULTS Cerebrospinal fluid shunt-and hydrocephalus-related surgeries accounted for 3245 (40.8%) of the 7942 procedures. Spinal procedures, craniotomy for tumor resections, craniotomy for traumatic injury, and craniofacial reconstructions accounted for an additional 8.7%, 6.8%, 4.5%, and 4.5% of surgical volume. There were 221 reoperations within 48 hours of the index surgery, yielding an overall incidence of 2.78%; 159 of the reoperation were unplanned. Of these 159 unplanned reoperations, 121 followed index operations involving shunt manipulations. Using unplanned reoperations as the dependent variable (n = 159), index operations with a starting time after 3 pm and admission through the emergency department (ED) were associated with a two- to threefold increase in the likelihood of reoperations (after-hour surgery, odds ratio [OR] 2.01 [95% CI 1.43-2.83, p < 0.001]; ED admission, OR 1.97 (95% CI 1.32-2.96, p < 0.05]). CONCLUSIONS Approximately 25% of the reoperations within 48 hours of a pediatric neurosurgical procedure were planned. When

  19. 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,…

  20. Confirmatory factor analysis applied to the Force Concept Inventory

    NASA Astrophysics Data System (ADS)

    Eaton, Philip; Willoughby, Shannon D.

    2018-06-01

    In 1995, Huffman and Heller used exploratory factor analysis to draw into question the factors of the Force Concept Inventory (FCI). Since then several papers have been published examining the factors of the FCI on larger sets of student responses and understandable factors were extracted as a result. However, none of these proposed factor models have been verified to not be unique to their original sample through the use of independent sets of data. This paper seeks to confirm the factor models proposed by Scott et al. in 2012, and Hestenes et al. in 1992, as well as another expert model proposed within this study through the use of confirmatory factor analysis (CFA) and a sample of 20 822 postinstruction student responses to the FCI. Upon application of CFA using the full sample, all three models were found to fit the data with acceptable global fit statistics. However, when CFA was performed using these models on smaller sample sizes the models proposed by Scott et al. and Eaton and Willoughby were found to be far more stable than the model proposed by Hestenes et al. The goodness of fit of these models to the data suggests that the FCI can be scored on factors that are not unique to a single class. These scores could then be used to comment on how instruction methods effect the performance of students along a single factor and more in-depth analyses of curriculum changes may be possible as a result.

  1. Toward Reflective Judgment in Exploratory Factor Analysis Decisions: Determining the Extraction Method and Number of Factors To Retain.

    ERIC Educational Resources Information Center

    Knight, Jennifer L.

    This paper considers some decisions that must be made by the researcher conducting an exploratory factor analysis. The primary purpose is to aid the researcher in making informed decisions during the factor analysis instead of relying on defaults in statistical programs or traditions of previous researchers. Three decision areas are addressed.…

  2. The computational structural mechanics testbed procedures manual

    NASA Technical Reports Server (NTRS)

    Stewart, Caroline B. (Compiler)

    1991-01-01

    The purpose of this manual is to document the standard high level command language procedures of the Computational Structural Mechanics (CSM) Testbed software system. A description of each procedure including its function, commands, data interface, and use is presented. This manual is designed to assist users in defining and using command procedures to perform structural analysis in the CSM Testbed User's Manual and the CSM Testbed Data Library Description.

  3. Critical Factors Analysis for Offshore Software Development Success by Structural Equation Modeling

    NASA Astrophysics Data System (ADS)

    Wada, Yoshihisa; Tsuji, Hiroshi

    In order to analyze the success/failure factors in offshore software development service by the structural equation modeling, this paper proposes to follow two approaches together; domain knowledge based heuristic analysis and factor analysis based rational analysis. The former works for generating and verifying of hypothesis to find factors and causalities. The latter works for verifying factors introduced by theory to build the model without heuristics. Following the proposed combined approaches for the responses from skilled project managers of the questionnaire, this paper found that the vendor property has high causality for the success compared to software property and project property.

  4. A Comparison of Coverage Restrictions for Biopharmaceuticals and Medical Procedures.

    PubMed

    Chambers, James; Pope, Elle; Bungay, Kathy; Cohen, Joshua; Ciarametaro, Michael; Dubois, Robert; Neumann, Peter J

    2018-04-01

    Differences in payer evaluation and coverage of pharmaceuticals and medical procedures suggest that coverage may differ for medications and procedures independent of their clinical benefit. We hypothesized that coverage for medications is more restricted than corresponding coverage for nonmedication interventions. We included top-selling medications and highly utilized procedures. For each intervention-indication pair, we classified value in terms of cost-effectiveness (incremental cost per quality-adjusted life-year), as reported by the Tufts Medical Center Cost-Effectiveness Analysis Registry. For each intervention-indication pair and for each of 10 large payers, we classified coverage, when available, as either "more restrictive" or as "not more restrictive," compared with a benchmark. The benchmark reflected the US Food and Drug Administration label information, when available, or pertinent clinical guidelines. We compared coverage policies and the benchmark in terms of step edits and clinical restrictions. Finally, we regressed coverage restrictiveness against intervention type (medication or nonmedication), controlling for value (cost-effectiveness more or less favorable than a designated threshold). We identified 392 medication and 185 procedure coverage decisions. A total of 26.3% of the medication coverage and 38.4% of the procedure coverage decisions were more restrictive than their corresponding benchmarks. After controlling for value, the odds of being more restrictive were 42% lower for medications than for procedures. Including unfavorable tier placement in the definition of "more restrictive" greatly increased the proportion of medication coverage decisions classified as "more restrictive" and reversed our findings. Therapy access depends on factors other than cost and clinical benefit, suggesting potential health care system inefficiency. Copyright © 2018 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by

  5. NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR EXTRACTION OF AIR SAMPLES FOR GC/MS ANALYSIS OF PESTICIDES (BCO-L-11.0)

    EPA Science Inventory

    The purpose of this SOP is to describe the procedures for extracting and preparing an air sample consisting of a polyurethane foam (PUF) plug and Teflon-coated glass fiber filter (Pallflex T60A20) for analysis of pesticides. This procedure covers sample preparation for samples t...

  6. 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,…

  7. Post-ERCP acute pancreatitis and its risk factors.

    PubMed

    Iorgulescu, A; Sandu, I; Turcu, F; Iordache, N

    2013-03-15

    Endoscopic retrograde cholangiopancreatography (ERCP) is a complex endoscopic technique that evolved from a diagnostic to a mainly therapeutic procedure. This was due to the identification of post-procedural complications that can follow both simple ERCP and that associated with the instrumentation of the biliary and pancreatic ductals. The identification of post ERCP complications in a proportion of 5 to 10% of cases, with a mortality rate of 0.33%, imposed their analysis and study of risk factors involved in their occurrence. The significance of post ERCP complications reveals the necessity of their avoidance by adopting additional measures if risk factors are identified. We have retrospectively analyzed 900 cases that underwent ERCP in the Surgery Department of "Sf. Ioan" Clinical Hospital in a period of 17 years. The complications of the procedure were studied. Among them, a special attention was given to post-ERCP acute pancreatitis (pERCP-AP), the most common complication that occurred in the study group. We also tried to find out and highlight the risk factors for this complication. ERCP is a relatively safe invasive procedure, yet it has complications (8% of cases), some of them potentially fatal (mortality 0.43%). The most common complications after ERCP are acute pancreatitis (3.7%), papillary bleeding (1.04%), retroperitoneal duodenal perforation (0.69%) and biliary septic complications like acute cholecystitis and cholangitis (1.21%). Acute pancreatitis is by far the most common complication. Risk factors for its occurrence are difficult sphincterotomy with precut use, failure of CBD desobstruction, pancreatic sphincterotomy, repeated injection of contrast in the pancreatic ductal system, dysfunction of the sphincter of Oddi and the absence of changes of chronic pancreatitis. When risk factors are identified, the patients' selection must be very strict and diagnostic ERCP should be avoided in favor of non-invasive diagnostic methods (MRI

  8. Spinal Surgeon Variation in Single-Level Cervical Fusion Procedures: A Cost and Hospital Resource Utilization Analysis.

    PubMed

    Hijji, Fady Y; Massel, Dustin H; Mayo, Benjamin C; Narain, Ankur S; Long, William W; Modi, Krishna D; Burke, Rory M; Canar, Jeff; Singh, Kern

    2017-07-01

    Retrospective analysis. To compare perioperative costs and outcomes of patients undergoing single-level anterior cervical discectomy and fusions (ACDF) at both a service (orthopedic vs. neurosurgical) and individual surgeon level. Hospital systems are experiencing significant pressure to increase value of care by reducing costs while maintaining or improving patient-centered outcomes. Few studies have examined the cost-effectiveness cervical arthrodesis at a service level. A retrospective review of patients who underwent a primary 1-level ACDF by eight surgeons (four orthopedic and four neurosurgical) at a single academic institution between 2013 and 2015 was performed. Patients were identified by Diagnosis-Related Group and procedural codes. Patients with the ninth revision of the International Classification of Diseases coding for degenerative cervical pathology were included. Patients were excluded if they exhibited preoperative diagnoses or postoperative social work issues affecting their length of stay. Comparisons of preoperative demographics were performed using Student t tests and chi-squared analysis. Perioperative outcomes and costs for hospital services were compared using multivariate regression adjusted for preoperative characteristics. A total of 137 patients diagnosed with cervical degeneration underwent single-level ACDF; 44 and 93 were performed by orthopedic surgeons and neurosurgeons, respectively. There was no difference in patient demographics. ACDF procedures performed by orthopedic surgeons demonstrated shorter operative times (89.1 ± 25.5 vs. 96.0 ± 25.5 min; P = 0.002) and higher laboratory costs (Δ+$6.53 ± $5.52 USD; P = 0.041). There were significant differences in operative time (P = 0.014) and labor costs (P = 0.034) between individual surgeons. There was no difference in total costs between specialties or individual surgeons. Surgical subspecialty training does not significantly affect total costs of

  9. Biliary bypass surgery – Analysis of indications & outcome of different procedures

    PubMed Central

    Hussain Talpur, K.Altaf; Mahmood Malik, Arshad; Iqbal Memon, Amir; Naeem Qureshi, Jawed; Khan Sangrasi, Ahmed; Laghari, Abdul Aziz

    2013-01-01

    Objectives: This study reports the indications and outcome of various biliary bypass surgical procedures from a single centre over a period of 10 years. Methods: This is a prospective observational study conducted over a period of 10 years (January 2001-december 2010). A total of 1500 patients were included, who underwent pancreatico-biliary surgery due to common bile duct (CBD) stones, congenital anomalies of biliary tree, unoperable pancreatico-biliary malignancies, CBD strictures and cases who developed iatrogenic biliary injuries during cholecystectomy (both open & laproscopic) during this period of time. The patients who required biliary bypass surgery were further analysed for indications and outcome. Results: Out of 1500 patients 83(5.53%) required biliary bypass surgical procedures. The CBD stones were observed as the most common indication (25.3%), followed by CBD injuries after open(10.84%) or laproscopic-cholecystectomy (14.46%), carcinoma head of pancreas (12.05%) and CBD obstruction(14.46%) either due to CBD strictures or unknown distal obstruction. Roux-en-Y-hepatico-jejunostomy (26.51%) was the most frequently performed procedure, followed by choledochoduodenostomy and Roux-en-Y choledocho-jejunostomy (i.e. 25.3% and 12.05% respectively). Roux-en-Y biliary bypass procedure was observed to be associated with better outcome in terms of rate of complications as well duration of hospital stay. Conclusion: Biliary bypass surgical procedures are the better options to restore the continuity of biliary system in patients with iatrogenic biliary tree injuries and un-operable pancreatico-biliary malignancy. Roux-en-Y biliary bypass procedure is safe and problem solving method in these cases. PMID:24353631

  10. 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…

  11. Procedures for experimental measurement and theoretical analysis of large plastic deformations

    NASA Technical Reports Server (NTRS)

    Morris, R. E.

    1974-01-01

    Theoretical equations are derived and analytical procedures are presented for the interpretation of experimental measurements of large plastic strains in the surface of a plate. Orthogonal gage lengths established on the metal surface are measured before and after deformation. The change in orthogonality after deformation is also measured. Equations yield the principal strains, deviatoric stresses in the absence of surface friction forces, true stresses if the stress normal to the surface is known, and the orientation angle between the deformed gage line and the principal stress-strain axes. Errors in the measurement of nominal strains greater than 3 percent are within engineering accuracy. Applications suggested for this strain measurement system include the large-strain-stress analysis of impact test models, burst tests of spherical or cylindrical pressure vessels, and to augment small-strain instrumentation tests where large strains are anticipated.

  12. Sparse multivariate factor analysis regression models and its applications to integrative genomics analysis.

    PubMed

    Zhou, Yan; Wang, Pei; Wang, Xianlong; Zhu, Ji; Song, Peter X-K

    2017-01-01

    The multivariate regression model is a useful tool to explore complex associations between two kinds of molecular markers, which enables the understanding of the biological pathways underlying disease etiology. For a set of correlated response variables, accounting for such dependency can increase statistical power. Motivated by integrative genomic data analyses, we propose a new methodology-sparse multivariate factor analysis regression model (smFARM), in which correlations of response variables are assumed to follow a factor analysis model with latent factors. This proposed method not only allows us to address the challenge that the number of association parameters is larger than the sample size, but also to adjust for unobserved genetic and/or nongenetic factors that potentially conceal the underlying response-predictor associations. The proposed smFARM is implemented by the EM algorithm and the blockwise coordinate descent algorithm. The proposed methodology is evaluated and compared to the existing methods through extensive simulation studies. Our results show that accounting for latent factors through the proposed smFARM can improve sensitivity of signal detection and accuracy of sparse association map estimation. We illustrate smFARM by two integrative genomics analysis examples, a breast cancer dataset, and an ovarian cancer dataset, to assess the relationship between DNA copy numbers and gene expression arrays to understand genetic regulatory patterns relevant to the disease. We identify two trans-hub regions: one in cytoband 17q12 whose amplification influences the RNA expression levels of important breast cancer genes, and the other in cytoband 9q21.32-33, which is associated with chemoresistance in ovarian cancer. © 2016 WILEY PERIODICALS, INC.

  13. Factor analysis of the Hamilton Depression Rating Scale in Parkinson's disease.

    PubMed

    Broen, M P G; Moonen, A J H; Kuijf, M L; Dujardin, K; Marsh, L; Richard, I H; Starkstein, S E; Martinez-Martin, P; Leentjens, A F G

    2015-02-01

    Several studies have validated the Hamilton Depression Rating Scale (HAMD) in patients with Parkinson's disease (PD), and reported adequate reliability and construct validity. However, the factorial validity of the HAMD has not yet been investigated. The aim of our analysis was to explore the factor structure of the HAMD in a large sample of PD patients. A principal component analysis of the 17-item HAMD was performed on data of 341 PD patients, available from a previous cross sectional study on anxiety. An eigenvalue ≥1 was used to determine the number of factors. Factor loadings ≥0.4 in combination with oblique rotations were used to identify which variables made up the factors. Kaiser-Meyer-Olkin measure (KMO), Cronbach's alpha, Bartlett's test, communality, percentage of non-redundant residuals and the component correlation matrix were computed to assess factor validity. KMO verified the sample's adequacy for factor analysis and Cronbach's alpha indicated a good internal consistency of the total scale. Six factors had eigenvalues ≥1 and together explained 59.19% of the variance. The number of items per factor varied from 1 to 6. Inter-item correlations within each component were low. There was a high percentage of non-redundant residuals and low communality. This analysis demonstrates that the factorial validity of the HAMD in PD is unsatisfactory. This implies that the scale is not appropriate for studying specific symptom domains of depression based on factorial structure in a PD population. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR ANALYSIS OF PASSIVE FORMALDEHYDE SAMPLERS (BCO-L-16.0)

    EPA Science Inventory

    The purpose of this SOP is to describe the methodology used by Air Quality Research (Research Triangle Park, NC) for the analysis of the PF-1 passive formaldehyde samplers using a colorimetric method and chromotropic acid. This procedure was followed to ensure consistent data re...

  15. Patient-specific risk factors for infection in arthroplasty procedure.

    PubMed

    Marmor, S; Kerroumi, Y

    2016-02-01

    All patients are not equally at risk when it comes to postoperative infections, whether the risks are related to the environment or the patient. Patient-specific infection risk factors for arthroplasty should be a focal point during the preoperative consultation as they impact the treatment decision. Eighty percent of patients have at least one modifiable infection risk factor. These risk factors must be corrected preoperatively whenever possible so that the patient is operated under the best possible conditions, with the lowest possible infection risk. The screenings and preoperative preparations are multidisciplinary but must also involve the patient. The information provided to the patient must match the patient's infectious risk profile. This lecture will review every infection risk factor, whether it is modifiable or not, and then suggest how the treatment decision should be adapted to each patient's infection risk. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  16. A DNA fingerprinting procedure for ultra high-throughput genetic analysis of insects.

    PubMed

    Schlipalius, D I; Waldron, J; Carroll, B J; Collins, P J; Ebert, P R

    2001-12-01

    Existing procedures for the generation of polymorphic DNA markers are not optimal for insect studies in which the organisms are often tiny and background molecular information is often non-existent. We have used a new high throughput DNA marker generation protocol called randomly amplified DNA fingerprints (RAF) to analyse the genetic variability in three separate strains of the stored grain pest, Rhyzopertha dominica. This protocol is quick, robust and reliable even though it requires minimal sample preparation, minute amounts of DNA and no prior molecular analysis of the organism. Arbitrarily selected oligonucleotide primers routinely produced approximately 50 scoreable polymorphic DNA markers, between individuals of three independent field isolates of R. dominica. Multivariate cluster analysis using forty-nine arbitrarily selected polymorphisms generated from a single primer reliably separated individuals into three clades corresponding to their geographical origin. The resulting clades were quite distinct, with an average genetic difference of 37.5 +/- 6.0% between clades and of 21.0 +/- 7.1% between individuals within clades. As a prelude to future gene mapping efforts, we have also assessed the performance of RAF under conditions commonly used in gene mapping. In this analysis, fingerprints from pooled DNA samples accurately and reproducibly reflected RAF profiles obtained from individual DNA samples that had been combined to create the bulked samples.

  17. Evaluating voice characteristics of first-year acting students in Israel: factor analysis.

    PubMed

    Amir, Ofer; Primov-Fever, Adi; Kushnir, Tami; Kandelshine-Waldman, Osnat; Wolf, Michael

    2013-01-01

    Acting students require diverse, high-quality, and high-intensity vocal performance from early stages of their training. Demanding vocal activities, before developing the appropriate vocal skills, put them in high risk for developing vocal problems. A retrospective analysis of voice characteristics of first-year acting students using several voice evaluation tools. A total of 79 first-year acting students (55 women and 24 men) were assigned into two study groups: laryngeal findings (LFs) and no laryngeal findings, based on stroboscopic findings. Their voice characteristics were evaluated using acoustic analysis, aerodynamic examination, perceptual scales, and self-report questionnaires. Results obtained from each set of measures were examined using a factor analysis approach. Significant differences between the two groups were found for a single fundamental frequency (F(0))-Regularity factor; a single Grade, Roughness, Breathiness, Asthenia, Strain perceptual factor; and the three self-evaluation factors. Gender differences were found for two acoustic analysis factors, which were based on F(0) and its derivatives, namely an aerodynamic factor that represents expiratory volume measurements and a single self-evaluation factor that represents the tendency to seek therapy. Approximately 50% of the first-year acting students had LFs. These students differed from their peers in the control group in a single acoustic analysis factor, as well as perceptual and self-report factors. No group differences, however, were found for the aerodynamic factors. Early laryngeal examination and voice evaluation of future professional voice users could provide a valuable individual baseline, to which later examinations could be compared, and assist in providing personally tailored treatment. Copyright © 2013 The Voice Foundation. Published by Mosby, Inc. All rights reserved.

  18. A modification of procedures for petrographic analysis of tertiary Indonesian coals

    NASA Astrophysics Data System (ADS)

    Moore, T. A.; Ferm, J. C.

    A study undertaken to characterize the Eocene coals from southeast Kalimantan has shown that standard preparation procedures fail to capture some basic petrographic properties of the coal. Modification of these procedures permits recognition of distinct plant parts and tissues embedded in finer grained matrix components. Plant parts and tissues can be classified on the basis of morphology and degree of degradation. The highest concentration and best preservation of plant parts and tissues occurs in banded coal and is lowest in the non-banded coal. Use of these procedures, which relates megascopic appearance to petrographic character, should allow more precise utilization of the coal.

  19. Procedures in complex systems: the airline cockpit.

    PubMed

    Degani, A; Wiener, E L

    1997-05-01

    In complex human-machine systems, successful operations depend on an elaborate set of procedures which are specified by the operational management of the organization. These procedures indicate to the human operator (in this case the pilot) the manner in which operational management intends to have various tasks done. The intent is to provide guidance to the pilots and to ensure a safe, logical, efficient, and predictable (standardized) means of carrying out the objectives of the job. However, procedures can become a hodge-podge. Inconsistent or illogical procedures may lead to noncompliance by operators. Based on a field study with three major airlines, the authors propose a model for procedure development called the "Four P's": philosophy, policies, procedures, and practices. Using this model as a framework, the authors discuss the intricate issue of designing flight-deck procedures, and propose a conceptual approach for designing any set of procedures. The various factors, both external and internal to the cockpit, that must be considered for procedure design are presented. In particular, the paper addresses the development of procedures for automated cockpits--a decade-long, and highly controversial issue in commercial aviation. Although this paper is based on airline operations, we assume that the principles discussed here are also applicable to other high-risk supervisory control systems, such as space flight, manufacturing process control, nuclear power production, and military operations.

  20. Reversal of Hartmann's procedure: a high-risk operation?

    PubMed

    Schmelzer, Thomas M; Mostafa, Gamal; Norton, H James; Newcomb, William L; Hope, William W; Lincourt, Amy E; Kercher, Kent W; Kuwada, Timothy S; Gersin, Keith S; Heniford, B Todd

    2007-10-01

    Patients who undergo Hartmann's procedure often do not have their colostomy closed based on the perceived risk of the operation. This study evaluated the outcome of reversal of Hartmann's procedure based on preoperative risk factors. We retrospectively reviewed adult patients who underwent reversal of Hartmann's procedure at our tertiary referral institution. Patient outcomes were compared based on identified risk factors (age >60 years, American Society of Anesthesiologists [ASA] score >2, and >2 preoperative comorbidities). One-hundred thirteen patients were included. Forty-four patients (39%) had an ASA score of >or=3. The mean hospital duration of stay was 6.8 days. There were 28 (25%) postoperative complications and no mortality. Patients >60 years old had significantly longer LOS compared with the rest of the group (P = .02). There were no differences in outcomes between groups based on ASA score or the presence of multiple preoperative comorbidities. An albumin level of <3.5 was the only significant predictor of postoperative complications (P = .04). The reversal of Hartmann's operation appears to be a safe operation with acceptable morbidity rates and can be considered in patients, including those with significant operative risk factors.

  1. Association of code status discussion with invasive procedures among advanced-stage cancer and noncancer patients.

    PubMed

    Sasaki, Akinori; Hiraoka, Eiji; Homma, Yosuke; Takahashi, Osamu; Norisue, Yasuhiro; Kawai, Koji; Fujitani, Shigeki

    2017-01-01

    Code status discussion is associated with a decrease in invasive procedures among terminally ill cancer patients. We investigated the association between code status discussion on admission and incidence of invasive procedures, cardiopulmonary resuscitation (CPR), and opioid use among inpatients with advanced stages of cancer and noncancer diseases. We performed a retrospective cohort study in a single center, Ito Municipal Hospital, Japan. Participants were patients who were admitted to the Department of Internal Medicine between October 1, 2013 and August 30, 2015, with advanced-stage cancer and noncancer. We collected demographic data and inquired the presence or absence of code status discussion within 24 hours of admission and whether invasive procedures, including central venous catheter placement, intubation with mechanical ventilation, and CPR for cardiac arrest, and opioid treatment were performed. We investigated the factors associated with CPR events by using multivariate logistic regression analysis. Among the total 232 patients, code status was discussed with 115 patients on admission, of which 114 (99.1%) patients had do-not-resuscitate (DNR) orders. The code status was not discussed with the remaining 117 patients on admission, of which 69 (59%) patients had subsequent code status discussion with resultant DNR orders. Code status discussion on admission decreased the incidence of central venous catheter placement, intubation with mechanical ventilation, and CPR in both cancer and noncancer patients. It tended to increase the rate of opioid use. Code status discussion on admission was the only factor associated with the decreased use of CPR ( P <0.001, odds ratio =0.03, 95% CI =0.004-0.21), which was found by using multivariate logistic regression analysis. Code status discussion on admission is associated with a decrease in invasive procedures and CPR in cancer and noncancer patients. Physicians should be educated about code status discussion to

  2. Cost-consequence analysis of different active flowable hemostatic matrices in cardiac surgical procedures.

    PubMed

    Makhija, D; Rock, M; Xiong, Y; Epstein, J D; Arnold, M R; Lattouf, O M; Calcaterra, D

    2017-06-01

    A recent retrospective comparative effectiveness study found that use of the FLOSEAL Hemostatic Matrix in cardiac surgery was associated with significantly lower risks of complications, blood transfusions, surgical revisions, and shorter length of surgery than use of SURGIFLO Hemostatic Matrix. These outcome improvements in cardiac surgery procedures may translate to economic savings for hospitals and payers. The objective of this study was to estimate the cost-consequence of two flowable hemostatic matrices (FLOSEAL or SURGIFLO) in cardiac surgeries for US hospitals. A cost-consequence model was constructed using clinical outcomes from a previously published retrospective comparative effectiveness study of FLOSEAL vs SURGIFLO in adult cardiac surgeries. The model accounted for the reported differences between these products in length of surgery, rates of major and minor complications, surgical revisions, and blood product transfusions. Costs were derived from Healthcare Cost and Utilization Project's National Inpatient Sample (NIS) 2012 database and converted to 2015 US dollars. Savings were modeled for a hospital performing 245 cardiac surgeries annually, as identified as the average for hospitals in the NIS dataset. One-way sensitivity analysis and probabilistic sensitivity analysis were performed to test model robustness. The results suggest that if FLOSEAL is utilized in a hospital that performs 245 mixed cardiac surgery procedures annually, 11 major complications, 31 minor complications, nine surgical revisions, 79 blood product transfusions, and 260.3 h of cumulative operating time could be avoided. These improved outcomes correspond to a net annualized saving of $1,532,896. Cost savings remained consistent between $1.3m and $1.8m and between $911k and $2.4m, even after accounting for the uncertainty around clinical and cost inputs, in a one-way and probabilistic sensitivity analysis, respectively. Outcome differences associated with FLOSEAL vs SURGIFLO

  3. Designing Flight Deck Procedures

    NASA Technical Reports Server (NTRS)

    Degani, Asaf; Wiener, Earl

    2005-01-01

    Three reports address the design of flight-deck procedures and various aspects of human interaction with cockpit systems that have direct impact on flight safety. One report, On the Typography of Flight- Deck Documentation, discusses basic research about typography and the kind of information needed by designers of flight deck documentation. Flight crews reading poorly designed documentation may easily overlook a crucial item on the checklist. The report surveys and summarizes the available literature regarding the design and typographical aspects of printed material. It focuses on typographical factors such as proper typefaces, character height, use of lower- and upper-case characters, line length, and spacing. Graphical aspects such as layout, color coding, fonts, and character contrast are discussed; and several cockpit conditions such as lighting levels and glare are addressed, as well as usage factors such as angular alignment, paper quality, and colors. Most of the insights and recommendations discussed in this report are transferable to paperless cockpit systems of the future and computer-based procedure displays (e.g., "electronic flight bag") in aerospace systems and similar systems that are used in other industries such as medical, nuclear systems, maritime operations, and military systems.

  4. Scientific literacy: Factor structure and gender differences

    NASA Astrophysics Data System (ADS)

    Manhart, James Joseph

    The purpose of this study was to investigate the factor structure of scientific literacy and to document any gender differences with respect to each factor. Participants included 1139 students (574 females, 565 males) in grades 9 through 12 who were taking a science class at one of four Midwestern high schools. Based on National Science Education Standards, a 100 item multiple-choice test was constructed to assess scientific literacy. Confirmatory factor analysis of item parcels suggested a three factor model was the best way to explain the data resulting from the administration of this test. The factors were labeled constructs of science, abilities necessary to do scientific inquiry, and social aspects of science. Gender differences with respect to these factors were examined using analysis of variance procedures. Because differential enrollment in science classes could cause gender differences in grades 11 and 12, parallel analyses were conducted on the grades 9 and 10 subsample and the grades 11 and 12 subsample. However, the results of the two analyses were similar. The most consistent gender difference observed was that females performed better than males on the social aspects of science factor. Males tended to perform better than females on the constructs of science factor, although no consistent gender difference was noted for items dealing with life science. With respect to the abilities necessary to do scientific inquiry factor, females tended to perform better than males in grades 9 and 10, while no consistent gender difference was observed in grades 11 and 12. Gender differences were also examined using the Mantel-Haenszel procedure to flag individual items that functioned differently for females and males of the same ability. Twelve items were flagged for grades 9 and 10 (8 in favor of females, 4 in favor of males). Fourteen items were flagged for grades 11 and 12 (7 in favor of females, 7 in favor of males). All of the flagged items exhibited only

  5. Current evidence on the role of smoking in plastic surgery elective procedures: A systematic review and meta-analysis.

    PubMed

    Theocharidis, Vasileios; Katsaros, Ioannis; Sgouromallis, Emmanouil; Serifis, Nikolaos; Boikou, Vasileios; Tasigiorgos, Sotirios; Kokosis, George; Economopoulos, Konstantinos P

    2018-05-01

    Smoking is considered to be a significant risk factor for the development of postoperative complications after various surgical procedures, mainly by limiting oxygen delivery to tissues. Evidence on the collective impact of smoking in aesthetic procedure outcomes is scarce. The aim of this study is to evaluate the current evidence on the association between smoking and postoperative outcomes in patients who underwent common elective procedures in plastic surgery. PubMed and Cochrane bibliographical databases were searched from January 1950 to October 2016 for studies reporting on patients who underwent facelift, abdominoplasty, breast reduction and breast reconstruction and for studies with included data on smoking history of treated patients. Fifty-three studies reporting on postoperative complications in tobacco users undergoing facelift, abdominoplasty, breast reduction and reconstruction were identified. Tobacco use is found to significantly increase the total number of postoperative complications as far as abdominoplasty (OR: 5.43; 95% CI = 2.92-10.10), breast reduction (OR: 2.36; 95% CI = 1.64-3.39) and breast reconstruction (OR: 1.91; 95% CI = 1.69-2.17) are concerned. Smoking history does not significantly affect total postoperative complications after facelift procedures (OR: 3.36; 95% CI = 0.92-12.30). Smoking predisposes to surgical site infections, delayed wound healing and skin necrosis in patients undergoing the most common aesthetic procedures in plastic surgery. More rigorous and detailed reporting on the history of tobacco use and surgical outcomes following plastic surgery procedures is needed to better quantify the impact of smoking on the overall postoperative care for this patient population. Copyright © 2018 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  6. Assessment of modal-pushover-based scaling procedure for nonlinear response history analysis of ordinary standard bridges

    USGS Publications Warehouse

    Kalkan, E.; Kwong, N.

    2012-01-01

    The earthquake engineering profession is increasingly utilizing nonlinear response history analyses (RHA) to evaluate seismic performance of existing structures and proposed designs of new structures. One of the main ingredients of nonlinear RHA is a set of ground motion records representing the expected hazard environment for the structure. When recorded motions do not exist (as is the case in the central United States) or when high-intensity records are needed (as is the case in San Francisco and Los Angeles), ground motions from other tectonically similar regions need to be selected and scaled. The modal-pushover-based scaling (MPS) procedure was recently developed to determine scale factors for a small number of records such that the scaled records provide accurate and efficient estimates of “true” median structural responses. The adjective “accurate” refers to the discrepancy between the benchmark responses and those computed from the MPS procedure. The adjective “efficient” refers to the record-to-record variability of responses. In this paper, the accuracy and efficiency of the MPS procedure are evaluated by applying it to four types of existing Ordinary Standard bridges typical of reinforced concrete bridge construction in California. These bridges are the single-bent overpass, multi-span bridge, curved bridge, and skew bridge. As compared with benchmark analyses of unscaled records using a larger catalog of ground motions, it is demonstrated that the MPS procedure provided an accurate estimate of the engineering demand parameters (EDPs) accompanied by significantly reduced record-to-record variability of the EDPs. Thus, it is a useful tool for scaling ground motions as input to nonlinear RHAs of Ordinary Standard bridges.

  7. Establishing Evidence for Internal Structure Using Exploratory Factor Analysis

    ERIC Educational Resources Information Center

    Watson, Joshua C.

    2017-01-01

    Exploratory factor analysis (EFA) is a data reduction technique used to condense data into smaller sets of summary variables by identifying underlying factors potentially accounting for patterns of collinearity among said variables. Using an illustrative example, the 5 general steps of EFA are described with best practices for decision making…

  8. The SAM framework: modeling the effects of management factors on human behavior in risk analysis.

    PubMed

    Murphy, D M; Paté-Cornell, M E

    1996-08-01

    Complex engineered systems, such as nuclear reactors and chemical plants, have the potential for catastrophic failure with disastrous consequences. In recent years, human and management factors have been recognized as frequent root causes of major failures in such systems. However, classical probabilistic risk analysis (PRA) techniques do not account for the underlying causes of these errors because they focus on the physical system and do not explicitly address the link between components' performance and organizational factors. This paper describes a general approach for addressing the human and management causes of system failure, called the SAM (System-Action-Management) framework. Beginning with a quantitative risk model of the physical system, SAM expands the scope of analysis to incorporate first the decisions and actions of individuals that affect the physical system. SAM then links management factors (incentives, training, policies and procedures, selection criteria, etc.) to those decisions and actions. The focus of this paper is on four quantitative models of action that describe this last relationship. These models address the formation of intentions for action and their execution as a function of the organizational environment. Intention formation is described by three alternative models: a rational model, a bounded rationality model, and a rule-based model. The execution of intentions is then modeled separately. These four models are designed to assess the probabilities of individual actions from the perspective of management, thus reflecting the uncertainties inherent to human behavior. The SAM framework is illustrated for a hypothetical case of hazardous materials transportation. This framework can be used as a tool to increase the safety and reliability of complex technical systems by modifying the organization, rather than, or in addition to, re-designing the physical system.

  9. An Evaluation on Factors Influencing Decision making for Malaysia Disaster Management: The Confirmatory Factor Analysis Approach

    NASA Astrophysics Data System (ADS)

    Zubir, S. N. A.; Thiruchelvam, S.; Mustapha, K. N. M.; Che Muda, Z.; Ghazali, A.; Hakimie, H.

    2017-12-01

    For the past few years, natural disaster has been the subject of debate in disaster management especially in flood disaster. Each year, natural disaster results in significant loss of life, destruction of homes and public infrastructure, and economic hardship. Hence, an effective and efficient flood disaster management would assure non-futile efforts for life saving. The aim of this article is to examine the relationship between approach, decision maker, influence factor, result, and ethic to decision making for flood disaster management in Malaysia. The key elements of decision making in the disaster management were studied based on the literature. Questionnaire surveys were administered among lead agencies at East Coast of Malaysia in the state of Kelantan and Pahang. A total of 307 valid responses had been obtained for further analysis. Exploratory Factor Analysis (EFA) and Confirmatory Factor Analysis (CFA) were carried out to analyse the measurement model involved in the study. The CFA for second-order reflective and first-order reflective measurement model indicates that approach, decision maker, influence factor, result, and ethic have a significant and direct effect on decision making during disaster. The results from this study showed that decision- making during disaster is an important element for disaster management to necessitate a successful collaborative decision making. The measurement model is accepted to proceed with further analysis known as Structural Equation Modeling (SEM) and can be assessed for the future research.

  10. NHEXAS PHASE I ARIZONA STUDY--STANDARD OPERATING PROCEDURE FOR EXTRACTION OF SOIL/HOUSE DUST FOR GC/MS ANALYSIS OF PESTICIDES (BCO-L-14.0)

    EPA Science Inventory

    The purpose of this SOP is to describe procedures for extracting and preparing dust or soil samples for gas chromatography/mass spectrometry (GC/MS) analysis of pesticides. This procedure was followed to ensure consistent data retrieval during the Arizona NHEXAS project and the "...

  11. Soil Gas Sampling Operating Procedure

    EPA Pesticide Factsheets

    EPA Region 4 Science and Ecosystem Support Division (SESD) document that describes general and specific procedures, methods, and considerations when collecting soil gas samples for field screening or laboratory analysis.

  12. Analysis of the influencing factors of global energy interconnection development

    NASA Astrophysics Data System (ADS)

    Zhang, Yi; He, Yongxiu; Ge, Sifan; Liu, Lin

    2018-04-01

    Under the background of building global energy interconnection and achieving green and low-carbon development, this paper grasps a new round of energy restructuring and the trend of energy technology change, based on the present situation of global and China's global energy interconnection development, established the index system of the impact of global energy interconnection development factors. A subjective and objective weight analysis of the factors affecting the development of the global energy interconnection was conducted separately by network level analysis and entropy method, and the weights are summed up by the method of additive integration, which gives the comprehensive weight of the influencing factors and the ranking of their influence.

  13. The vehicle design evaluation program - A computer-aided design procedure for transport aircraft

    NASA Technical Reports Server (NTRS)

    Oman, B. H.; Kruse, G. S.; Schrader, O. E.

    1977-01-01

    The vehicle design evaluation program is described. This program is a computer-aided design procedure that provides a vehicle synthesis capability for vehicle sizing, external load analysis, structural analysis, and cost evaluation. The vehicle sizing subprogram provides geometry, weight, and balance data for aircraft using JP, hydrogen, or methane fuels. The structural synthesis subprogram uses a multistation analysis for aerodynamic surfaces and fuselages to develop theoretical weights and geometric dimensions. The parts definition subprogram uses the geometric data from the structural analysis and develops the predicted fabrication dimensions, parts material raw stock buy requirements, and predicted actual weights. The cost analysis subprogram uses detail part data in conjunction with standard hours, realization factors, labor rates, and material data to develop the manufacturing costs. The program is used to evaluate overall design effects on subsonic commercial type aircraft due to parameter variations.

  14. Evaluation of vertical profiles to design continuous descent approach procedure

    NASA Astrophysics Data System (ADS)

    Pradeep, Priyank

    The current research focuses on predictability, variability and operational feasibility aspect of Continuous Descent Approach (CDA), which is among the key concepts of the Next Generation Air Transportation System (NextGen). The idle-thrust CDA is a fuel economical, noise and emission abatement procedure, but requires increased separation to accommodate for variability and uncertainties in vertical and speed profiles of arriving aircraft. Although a considerable amount of researches have been devoted to the estimation of potential benefits of the CDA, only few have attempted to explain the predictability, variability and operational feasibility aspect of CDA. The analytical equations derived using flight dynamics and Base of Aircraft and Data (BADA) Total Energy Model (TEM) in this research gives insight into dependency of vertical profile of CDA on various factors like wind speed and gradient, weight, aircraft type and configuration, thrust settings, atmospheric factors (deviation from ISA (DISA), pressure and density of the air) and descent speed profile. Application of the derived equations to idle-thrust CDA gives an insight into sensitivity of its vertical profile to multiple factors. This suggests fixed geometric flight path angle (FPA) CDA has higher degree of predictability and lesser variability at the cost of non-idle and low thrust engine settings. However, with optimized design this impact can be overall minimized. The CDA simulations were performed using Future ATM Concept Evaluation Tool (FACET) based on radar-track and aircraft type data (BADA) of the real air-traffic to some of the busiest airports in the USA (ATL, SFO and New York Metroplex (JFK, EWR and LGA)). The statistical analysis of the vertical profiles of CDA shows 1) mean geometric FPAs derived from various simulated vertical profiles are consistently shallower than 3° glideslope angle and 2) high level of variability in vertical profiles of idle-thrust CDA even in absence of

  15. Procedural learning is impaired in dyslexia: Evidence from a meta-analysis of serial reaction time studies☆

    PubMed Central

    Lum, Jarrad A.G.; Ullman, Michael T.; Conti-Ramsden, Gina

    2013-01-01

    A number of studies have investigated procedural learning in dyslexia using serial reaction time (SRT) tasks. Overall, the results have been mixed, with evidence of both impaired and intact learning reported. We undertook a systematic search of studies that examined procedural learning using SRT tasks, and synthesized the data using meta-analysis. A total of 14 studies were identified, representing data from 314 individuals with dyslexia and 317 typically developing control participants. The results indicate that, on average, individuals with dyslexia have worse procedural learning abilities than controls, as indexed by sequence learning on the SRT task. The average weighted standardized mean difference (the effect size) was found to be 0.449 (CI95: .204, .693), and was significant (p < .001). However, moderate levels of heterogeneity were found between study-level effect sizes. Meta-regression analyses indicated that studies with older participants that used SRT tasks with second order conditional sequences, or with older participants that used sequences that were presented a large number of times, were associated with smaller effect sizes. These associations are discussed with respect to compensatory and delayed memory systems in dyslexia. PMID:23920029

  16. A Procedure for the supercritical fluid extraction of coal samples, with subsequent analysis of extracted hydrocarbons

    USGS Publications Warehouse

    Kolak, Jonathan J.

    2006-01-01

    Introduction: This report provides a detailed, step-by-step procedure for conducting extractions with supercritical carbon dioxide (CO2) using the ISCO SFX220 supercritical fluid extraction system. Protocols for the subsequent separation and analysis of extracted hydrocarbons are also included in this report. These procedures were developed under the auspices of the project 'Assessment of Geologic Reservoirs for Carbon Dioxide Sequestration' (see http://pubs.usgs.gov/fs/fs026-03/fs026-03.pdf) to investigate possible environmental ramifications associated with CO2 storage (sequestration) in geologic reservoirs, such as deep (~1 km below land surface) coal beds. Supercritical CO2 has been used previously to extract contaminants from geologic matrices. Pressure-temperature conditions within deep coal beds may render CO2 supercritical. In this context, the ability of supercritical CO2 to extract contaminants from geologic materials may serve to mobilize noxious compounds from coal, possibly complicating storage efforts. There currently exists little information on the physicochemical interactions between supercritical CO2 and coal in this setting. The procedures described herein were developed to improve the understanding of these interactions and provide insight into the fate of CO2 and contaminants during simulated CO2 injections.

  17. Pleural procedures in the management of malignant effusions

    PubMed Central

    Ferreiro, Lucía; Suárez-Antelo, Juan; Valdés, Luis

    2017-01-01

    Malignant pleural effusion (MPE) is common in clinical practice, and despite the existence of studies to guide clinical decisions, it often poses diagnostic and therapeutic dilemmas. Once it is diagnosed, median survival does not usually exceed 6 months. The management of these patients focuses on symptom relief since no treatments have been shown to increase survival to date. Conversely, poor management can shorten survival. The approach must be multidisciplinary and allow for individualized care. Initial diagnostic procedures should be minimally invasive and, according to the results and other factors, procedures of increasing complexity will be selecting. Likewise, the treatment of MPEs should be individualized according to factors such as type of tumor, patient functional status, means available, benefits of each procedure, or life expectancy. Currently, treatment seems to tend toward less interventional approaches, in which patients can be managed on an outpatient basis, thus minimizing both the discomfort that more aggressive approaches involve and the costs of care associated with this disease. This article reviews the pleural procedures employed in the management of MPEs with special emphasis on the indication for each one, its usefulness, benefits, and complications. PMID:28197215

  18. Examining Evolving Performance on the Force Concept Inventory Using Factor Analysis

    ERIC Educational Resources Information Center

    Semak, M. R.; Dietz, R. D.; Pearson, R. H.; Willis, C. W

    2017-01-01

    The application of factor analysis to the "Force Concept Inventory" (FCI) has proven to be problematic. Some studies have suggested that factor analysis of test results serves as a helpful tool in assessing the recognition of Newtonian concepts by students. Other work has produced at best ambiguous results. For the FCI administered as a…

  19. A Markov Chain Monte Carlo Approach to Confirmatory Item Factor Analysis

    ERIC Educational Resources Information Center

    Edwards, Michael C.

    2010-01-01

    Item factor analysis has a rich tradition in both the structural equation modeling and item response theory frameworks. The goal of this paper is to demonstrate a novel combination of various Markov chain Monte Carlo (MCMC) estimation routines to estimate parameters of a wide variety of confirmatory item factor analysis models. Further, I show…

  20. 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…