Statistical Analysis for Multisite Trials Using Instrumental Variables with Random Coefficients

ERIC Educational Resources Information Center

Raudenbush, Stephen W.; Reardon, Sean F.; Nomi, Takako

2012-01-01

Multisite trials can clarify the average impact of a new program and the heterogeneity of impacts across sites. Unfortunately, in many applications, compliance with treatment assignment is imperfect. For these applications, we propose an instrumental variable (IV) model with person-specific and site-specific random coefficients. Site-specific IV…

Using instrumental variables to estimate a Cox's proportional hazards regression subject to additive confounding

PubMed Central

Tosteson, Tor D.; Morden, Nancy E.; Stukel, Therese A.; O'Malley, A. James

2014-01-01

The estimation of treatment effects is one of the primary goals of statistics in medicine. Estimation based on observational studies is subject to confounding. Statistical methods for controlling bias due to confounding include regression adjustment, propensity scores and inverse probability weighted estimators. These methods require that all confounders are recorded in the data. The method of instrumental variables (IVs) can eliminate bias in observational studies even in the absence of information on confounders. We propose a method for integrating IVs within the framework of Cox's proportional hazards model and demonstrate the conditions under which it recovers the causal effect of treatment. The methodology is based on the approximate orthogonality of an instrument with unobserved confounders among those at risk. We derive an estimator as the solution to an estimating equation that resembles the score equation of the partial likelihood in much the same way as the traditional IV estimator resembles the normal equations. To justify this IV estimator for a Cox model we perform simulations to evaluate its operating characteristics. Finally, we apply the estimator to an observational study of the effect of coronary catheterization on survival. PMID:25506259

Using instrumental variables to estimate a Cox's proportional hazards regression subject to additive confounding.

PubMed

MacKenzie, Todd A; Tosteson, Tor D; Morden, Nancy E; Stukel, Therese A; O'Malley, A James

2014-06-01

The estimation of treatment effects is one of the primary goals of statistics in medicine. Estimation based on observational studies is subject to confounding. Statistical methods for controlling bias due to confounding include regression adjustment, propensity scores and inverse probability weighted estimators. These methods require that all confounders are recorded in the data. The method of instrumental variables (IVs) can eliminate bias in observational studies even in the absence of information on confounders. We propose a method for integrating IVs within the framework of Cox's proportional hazards model and demonstrate the conditions under which it recovers the causal effect of treatment. The methodology is based on the approximate orthogonality of an instrument with unobserved confounders among those at risk. We derive an estimator as the solution to an estimating equation that resembles the score equation of the partial likelihood in much the same way as the traditional IV estimator resembles the normal equations. To justify this IV estimator for a Cox model we perform simulations to evaluate its operating characteristics. Finally, we apply the estimator to an observational study of the effect of coronary catheterization on survival.

Comparison of variance estimators for meta-analysis of instrumental variable estimates

PubMed Central

Schmidt, AF; Hingorani, AD; Jefferis, BJ; White, J; Groenwold, RHH; Dudbridge, F

2016-01-01

Abstract Background: Mendelian randomization studies perform instrumental variable (IV) analysis using genetic IVs. Results of individual Mendelian randomization studies can be pooled through meta-analysis. We explored how different variance estimators influence the meta-analysed IV estimate. Methods: Two versions of the delta method (IV before or after pooling), four bootstrap estimators, a jack-knife estimator and a heteroscedasticity-consistent (HC) variance estimator were compared using simulation. Two types of meta-analyses were compared, a two-stage meta-analysis pooling results, and a one-stage meta-analysis pooling datasets. Results: Using a two-stage meta-analysis, coverage of the point estimate using bootstrapped estimators deviated from nominal levels at weak instrument settings and/or outcome probabilities ≤ 0.10. The jack-knife estimator was the least biased resampling method, the HC estimator often failed at outcome probabilities ≤ 0.50 and overall the delta method estimators were the least biased. In the presence of between-study heterogeneity, the delta method before meta-analysis performed best. Using a one-stage meta-analysis all methods performed equally well and better than two-stage meta-analysis of greater or equal size. Conclusions: In the presence of between-study heterogeneity, two-stage meta-analyses should preferentially use the delta method before meta-analysis. Weak instrument bias can be reduced by performing a one-stage meta-analysis. PMID:27591262

Latent class instrumental variables: A clinical and biostatistical perspective

PubMed Central

Baker, Stuart G.; Kramer, Barnett S.; Lindeman, Karen S.

2015-01-01

In some two-arm randomized trials, some participants receive the treatment assigned to the other arm as a result of technical problems, refusal of a treatment invitation, or a choice of treatment in an encouragement design. In some before-and-after studies, the availability of a new treatment changes from one time period to this next. Under assumptions that are often reasonable, the latent class instrumental variable (IV) method estimates the effect of treatment received in the aforementioned scenarios involving all-or-none compliance and all-or-none availability. Key aspects are four initial latent classes (sometimes called principal strata) based on treatment received if in each randomization group or time period, the exclusion restriction assumption (in which randomization group or time period is an instrumental variable), the monotonicity assumption (which drops an implausible latent class from the analysis), and the estimated effect of receiving treatment in one latent class (sometimes called efficacy, the local average treatment effect, or the complier average causal effect). Since its independent formulations in the biostatistics and econometrics literatures, the latent class IV method (which has no well-established name) has gained increasing popularity. We review the latent class IV method from a clinical and biostatistical perspective, focusing on underlying assumptions, methodological extensions, and applications in our fields of obstetrics and cancer research. PMID:26239275

The contextual effects of social capital on health: a cross-national instrumental variable analysis.

PubMed

Kim, Daniel; Baum, Christopher F; Ganz, Michael L; Subramanian, S V; Kawachi, Ichiro

2011-12-01

Past research on the associations between area-level/contextual social capital and health has produced conflicting evidence. However, interpreting this rapidly growing literature is difficult because estimates using conventional regression are prone to major sources of bias including residual confounding and reverse causation. Instrumental variable (IV) analysis can reduce such bias. Using data on up to 167,344 adults in 64 nations in the European and World Values Surveys and applying IV and ordinary least squares (OLS) regression, we estimated the contextual effects of country-level social trust on individual self-rated health. We further explored whether these associations varied by gender and individual levels of trust. Using OLS regression, we found higher average country-level trust to be associated with better self-rated health in both women and men. Instrumental variable analysis yielded qualitatively similar results, although the estimates were more than double in size in both sexes when country population density and corruption were used as instruments. The estimated health effects of raising the percentage of a country's population that trusts others by 10 percentage points were at least as large as the estimated health effects of an individual developing trust in others. These findings were robust to alternative model specifications and instruments. Conventional regression and to a lesser extent IV analysis suggested that these associations are more salient in women and in women reporting social trust. In a large cross-national study, our findings, including those using instrumental variables, support the presence of beneficial effects of higher country-level trust on self-rated health. Previous findings for contextual social capital using traditional regression may have underestimated the true associations. Given the close linkages between self-rated health and all-cause mortality, the public health gains from raising social capital within and across countries may be large. Copyright © 2011 Elsevier Ltd. All rights reserved.

The contextual effects of social capital on health: a cross-national instrumental variable analysis

PubMed Central

Kim, Daniel; Baum, Christopher F; Ganz, Michael; Subramanian, S V; Kawachi, Ichiro

2011-01-01

Past observational studies of the associations of area-level/contextual social capital with health have revealed conflicting findings. However, interpreting this rapidly growing literature is difficult because estimates using conventional regression are prone to major sources of bias including residual confounding and reverse causation. Instrumental variable (IV) analysis can reduce such bias. Using data on up to 167 344 adults in 64 nations in the European and World Values Surveys and applying IV and ordinary least squares (OLS) regression, we estimated the contextual effects of country-level social trust on individual self-rated health. We further explored whether these associations varied by gender and individual levels of trust. Using OLS regression, we found higher average country-level trust to be associated with better self-rated health in both women and men. Instrumental variable analysis yielded qualitatively similar results, although the estimates were more than double in size in women and men using country population density and corruption as instruments. The estimated health effects of raising the percentage of a country's population that trusts others by 10 percentage points were at least as large as the estimated health effects of an individual developing trust in others. These findings were robust to alternative model specifications and instruments. Conventional regression and to a lesser extent IV analysis suggested that these associations are more salient in women and in women reporting social trust. In a large cross-national study, our findings, including those using instrumental variables, support the presence of beneficial effects of higher country-level trust on self-rated health. Past findings for contextual social capital using traditional regression may have underestimated the true associations. Given the close linkages between self-rated health and all-cause mortality, the public health gains from raising social capital within countries may be large. PMID:22078106

Instrumental variables analysis using multiple databases: an example of antidepressant use and risk of hip fracture.

PubMed

Uddin, Md Jamal; Groenwold, Rolf H H; de Boer, Anthonius; Gardarsdottir, Helga; Martin, Elisa; Candore, Gianmario; Belitser, Svetlana V; Hoes, Arno W; Roes, Kit C B; Klungel, Olaf H

2016-03-01

Instrumental variable (IV) analysis can control for unmeasured confounding, yet it has not been widely used in pharmacoepidemiology. We aimed to assess the performance of IV analysis using different IVs in multiple databases in a study of antidepressant use and hip fracture. Information on adults with at least one prescription of a selective serotonin reuptake inhibitor (SSRI) or tricyclic antidepressant (TCA) during 2001-2009 was extracted from the THIN (UK), BIFAP (Spain), and Mondriaan (Netherlands) databases. IVs were created using the proportion of SSRI prescriptions per practice or using the one, five, or ten previous prescriptions by a physician. Data were analysed using conventional Cox regression and two-stage IV models. In the conventional analysis, SSRI (vs. TCA) was associated with an increased risk of hip fracture, which was consistently found across databases: the adjusted hazard ratio (HR) was approximately 1.35 for time-fixed and 1.50 to 2.49 for time-varying SSRI use, while the IV analysis based on the IVs that appeared to satisfy the IV assumptions showed conflicting results, e.g. the adjusted HRs ranged from 0.55 to 2.75 for time-fixed exposure. IVs for time-varying exposure violated at least one IV assumption and were therefore invalid. This multiple database study shows that the performance of IV analysis varied across the databases for time-fixed and time-varying exposures and strongly depends on the definition of IVs. It remains challenging to obtain valid IVs in pharmacoepidemiological studies, particularly for time-varying exposure, and IV analysis should therefore be interpreted cautiously. Copyright © 2016 John Wiley & Sons, Ltd.

Performing both propensity score and instrumental variable analyses in observational studies often leads to discrepant results: a systematic review.

PubMed

Laborde-Castérot, Hervé; Agrinier, Nelly; Thilly, Nathalie

2015-10-01

Propensity score (PS) and instrumental variable (IV) are analytical techniques used to adjust for confounding in observational research. More and more, they seem to be used simultaneously in studies evaluating health interventions. The present review aimed to analyze the agreement between PS and IV results in medical research published to date. Review of all published observational studies that evaluated a clinical intervention using simultaneously PS and IV analyses, as identified in MEDLINE and Web of Science. Thirty-seven studies, most of them published during the previous 5 years, reported 55 comparisons between results from PS and IV analyses. There was a slight/fair agreement between the methods [Cohen's kappa coefficient = 0.21 (95% confidence interval: 0.00, 0.41)]. In 23 cases (42%), results were nonsignificant for one method and significant for the other, and IV analysis results were nonsignificant in most situations (87%). Discrepancies are frequent between PS and IV analyses and can be interpreted in various ways. This suggests that researchers should carefully consider their analytical choices, and readers should be cautious when interpreting results, until further studies clarify the respective roles of the two methods in observational comparative effectiveness research. Copyright © 2015 Elsevier Inc. All rights reserved.

How the 2SLS/IV estimator can handle equality constraints in structural equation models: a system-of-equations approach.

PubMed

Nestler, Steffen

2014-05-01

Parameters in structural equation models are typically estimated using the maximum likelihood (ML) approach. Bollen (1996) proposed an alternative non-iterative, equation-by-equation estimator that uses instrumental variables. Although this two-stage least squares/instrumental variables (2SLS/IV) estimator has good statistical properties, one problem with its application is that parameter equality constraints cannot be imposed. This paper presents a mathematical solution to this problem that is based on an extension of the 2SLS/IV approach to a system of equations. We present an example in which our approach was used to examine strong longitudinal measurement invariance. We also investigated the new approach in a simulation study that compared it with ML in the examination of the equality of two latent regression coefficients and strong measurement invariance. Overall, the results show that the suggested approach is a useful extension of the original 2SLS/IV estimator and allows for the effective handling of equality constraints in structural equation models. © 2013 The British Psychological Society.

Estimating the effect of treatment rate changes when treatment benefits are heterogeneous: antibiotics and otitis media.

PubMed

Park, Tae-Ryong; Brooks, John M; Chrischilles, Elizabeth A; Bergus, George

2008-01-01

Contrast methods to assess the health effects of a treatment rate change when treatment benefits are heterogeneous across patients. Antibiotic prescribing for children with otitis media (OM) in Iowa Medicaid is the empirical example. Instrumental variable (IV) and linear probability model (LPM) are used to estimate the effect of antibiotic treatments on cure probabilities for children with OM in Iowa Medicaid. Local area physician supply per capita is the instrument in the IV models. Estimates are contrasted in terms of their ability to make inferences for patients whose treatment choices may be affected by a change in population treatment rates. The instrument was positively related to the probability of being prescribed an antibiotic. LPM estimates showed a positive effect of antibiotics on OM patient cure probability while IV estimates showed no relationship between antibiotics and patient cure probability. Linear probability model estimation yields the average effects of the treatment on patients that were treated. IV estimation yields the average effects for patients whose treatment choices were affected by the instrument. As antibiotic treatment effects are heterogeneous across OM patients, our estimates from these approaches are aligned with clinical evidence and theory. The average estimate for treated patients (higher severity) from the LPM model is greater than estimates for patients whose treatment choices are affected by the instrument (lower severity) from the IV models. Based on our IV estimates it appears that lowering antibiotic use in OM patients in Iowa Medicaid did not result in lost cures.

Latent class instrumental variables: a clinical and biostatistical perspective.

PubMed

Baker, Stuart G; Kramer, Barnett S; Lindeman, Karen S

2016-01-15

In some two-arm randomized trials, some participants receive the treatment assigned to the other arm as a result of technical problems, refusal of a treatment invitation, or a choice of treatment in an encouragement design. In some before-and-after studies, the availability of a new treatment changes from one time period to this next. Under assumptions that are often reasonable, the latent class instrumental variable (IV) method estimates the effect of treatment received in the aforementioned scenarios involving all-or-none compliance and all-or-none availability. Key aspects are four initial latent classes (sometimes called principal strata) based on treatment received if in each randomization group or time period, the exclusion restriction assumption (in which randomization group or time period is an instrumental variable), the monotonicity assumption (which drops an implausible latent class from the analysis), and the estimated effect of receiving treatment in one latent class (sometimes called efficacy, the local average treatment effect, or the complier average causal effect). Since its independent formulations in the biostatistics and econometrics literatures, the latent class IV method (which has no well-established name) has gained increasing popularity. We review the latent class IV method from a clinical and biostatistical perspective, focusing on underlying assumptions, methodological extensions, and applications in our fields of obstetrics and cancer research. Copyright © 2015 John Wiley & Sons, Ltd.

Instrumental variable applications using nursing home prescribing preferences in comparative effectiveness research.

PubMed

Huybrechts, Krista F; Gerhard, Tobias; Franklin, Jessica M; Levin, Raisa; Crystal, Stephen; Schneeweiss, Sebastian

2014-08-01

Nursing home residents are of particular interest for comparative effectiveness research given their susceptibility to adverse treatment effects and systematic exclusion from trials. However, the risk of residual confounding because of unmeasured markers of declining health using conventional analytic methods is high. We evaluated the validity of instrumental variable (IV) methods based on nursing home prescribing preference to mitigate such confounding, using psychotropic medications to manage behavioral problems in dementia as a case study. A cohort using linked data from Medicaid, Medicare, Minimum Data Set, and Online Survey, Certification and Reporting for 2001-2004 was established. Dual-eligible patients ≥65 years who initiated psychotropic medication use after admission were selected. Nursing home prescribing preference was characterized using mixed-effects logistic regression models. The plausibility of IV assumptions was explored, and the association between psychotropic medication class and 180-day mortality was estimated. High-prescribing and low-prescribing nursing homes differed by a factor of 2. Each preference-based IV measure described a substantial proportion of variation in psychotropic medication choice (β(IV → treatment): 0.22-0.36). Measured patient characteristics were well balanced across patient groups based on instrument status (52% average reduction in Mahalanobis distance). There was no evidence that instrument status was associated with markers of nursing home quality of care. Findings indicate that IV analyses using nursing home prescribing preference may be a useful approach in comparative effectiveness studies, and should extend naturally to analyses including untreated comparison groups, which are of great scientific interest but subject to even stronger confounding. Copyright © 2014 John Wiley & Sons, Ltd.

Instrumental variables vs. grouping approach for reducing bias due to measurement error.

PubMed

Batistatou, Evridiki; McNamee, Roseanne

2008-01-01

Attenuation of the exposure-response relationship due to exposure measurement error is often encountered in epidemiology. Given that error cannot be totally eliminated, bias correction methods of analysis are needed. Many methods require more than one exposure measurement per person to be made, but the `group mean OLS method,' in which subjects are grouped into several a priori defined groups followed by ordinary least squares (OLS) regression on the group means, can be applied with one measurement. An alternative approach is to use an instrumental variable (IV) method in which both the single error-prone measure and an IV are used in IV analysis. In this paper we show that the `group mean OLS' estimator is equal to an IV estimator with the group mean used as IV, but that the variance estimators for the two methods are different. We derive a simple expression for the bias in the common estimator which is a simple function of group size, reliability and contrast of exposure between groups, and show that the bias can be very small when group size is large. We compare this method with a new proposal (group mean ranking method), also applicable with a single exposure measurement, in which the IV is the rank of the group means. When there are two independent exposure measurements per subject, we propose a new IV method (EVROS IV) and compare it with Carroll and Stefanski's (CS IV) proposal in which the second measure is used as an IV; the new IV estimator combines aspects of the `group mean' and `CS' strategies. All methods are evaluated in terms of bias, precision and root mean square error via simulations and a dataset from occupational epidemiology. The `group mean ranking method' does not offer much improvement over the `group mean method.' Compared with the `CS' method, the `EVROS' method is less affected by low reliability of exposure. We conclude that the group IV methods we propose may provide a useful way to handle mismeasured exposures in epidemiology with or without replicate measurements. Our finding may also have implications for the use of aggregate variables in epidemiology to control for unmeasured confounding.

Treatment Effect Estimation Using Nonlinear Two-Stage Instrumental Variable Estimators: Another Cautionary Note.

PubMed

Chapman, Cole G; Brooks, John M

2016-12-01

To examine the settings of simulation evidence supporting use of nonlinear two-stage residual inclusion (2SRI) instrumental variable (IV) methods for estimating average treatment effects (ATE) using observational data and investigate potential bias of 2SRI across alternative scenarios of essential heterogeneity and uniqueness of marginal patients. Potential bias of linear and nonlinear IV methods for ATE and local average treatment effects (LATE) is assessed using simulation models with a binary outcome and binary endogenous treatment across settings varying by the relationship between treatment effectiveness and treatment choice. Results show that nonlinear 2SRI models produce estimates of ATE and LATE that are substantially biased when the relationships between treatment and outcome for marginal patients are unique from relationships for the full population. Bias of linear IV estimates for LATE was low across all scenarios. Researchers are increasingly opting for nonlinear 2SRI to estimate treatment effects in models with binary and otherwise inherently nonlinear dependent variables, believing that it produces generally unbiased and consistent estimates. This research shows that positive properties of nonlinear 2SRI rely on assumptions about the relationships between treatment effect heterogeneity and choice. © Health Research and Educational Trust.

Variability among Research Diagnostic Interview Instruments in the Application of "DSM-IV-TR" Criteria for Pediatric Bipolar Disorder

ERIC Educational Resources Information Center

Galanter, Cathryn A.; Hundt, Stephanie R.; Goyal, Parag; Le, Jenna; Fisher, Prudence W.

2012-01-01

Objective: The "DSM-IV-TR "criteria for a manic episode and bipolar disorder (BD) were developed for adults but are used for children. The manner in which clinicians and researchers interpret these criteria may have contributed to the increase in BD diagnoses given to youth. Research interviews are designed to improve diagnostic reliability and…

Comparative Analysis of Length of Stay and Inpatient Costs for Orthopedic Surgery Patients Treated with IV Acetaminophen and IV Opioids vs. IV Opioids Alone for Post-Operative Pain.

PubMed

Hansen, Ryan N; Pham, An; Strassels, Scott A; Balaban, Stela; Wan, George J

2016-09-01

Recovery from orthopedic surgery is oriented towards restoring functional health outcomes while reducing hospital length of stay (LOS) and medical expenditures. Optimal pain management is a key to reaching these objectives. We sought to compare orthopedic surgery patients who received combination intravenous (IV) acetaminophen and IV opioid analgesia to those who received IV opioids alone and compared the two groups on LOS and hospitalization costs. We performed a retrospective analysis of the Premier Database (Premier, Inc.; between January 2009 and June 2015) comparing orthopedic surgery patients who received post-operative pain management with combination IV acetaminophen and IV opioids to those who received only IV opioids starting on the day of surgery and continuing up to the second post-operative day. The quarterly rate of IV acetaminophen use for all hospitalizations by hospital served as the instrumental variable in two-stage least squares regressions controlling for patient and hospital covariates to compare the LOS and hospitalization costs of IV acetaminophen recipients to opioid monotherapy patients. We identified 4,85,895 orthopedic surgery patients with 1,74,805 (36%) who had received IV acetaminophen. Study subjects averaged 64 years of age and were predominantly non-Hispanic Caucasians (78%) and female (58%). The mean unadjusted LOS for IV acetaminophen patients was 3.2 days [standard deviation (SD) 2.6] compared to 3.9 days (SD 3.9) with only IV opioids (P < 0.0001). Average unadjusted hospitalization costs were $19,024.9 (SD $13,113.7) for IV acetaminophen patients and $19,927.6 (SD $19,578.8) for IV opioid patients (P < 0.0001). These differences remained statistically significant in our instrumental variable models, with IV acetaminophen associated with 0.51 days shorter hospitalization [95% confidence interval (CI) -0.58 to -0.44, P < 0.0001] and $634.8 lower hospitalization costs (95% CI -$1032.5 to -$237.1, P = 0.0018). Compared to opioids alone, managing post-orthopedic surgery pain with the addition of IV acetaminophen is associated with shorter LOS and decreased hospitalization costs. Mallinckrodt Pharmaceuticals.

Instrumental variables estimates of peer effects in social networks.

PubMed

An, Weihua

2015-03-01

Estimating peer effects with observational data is very difficult because of contextual confounding, peer selection, simultaneity bias, and measurement error, etc. In this paper, I show that instrumental variables (IVs) can help to address these problems in order to provide causal estimates of peer effects. Based on data collected from over 4000 students in six middle schools in China, I use the IV methods to estimate peer effects on smoking. My design-based IV approach differs from previous ones in that it helps to construct potentially strong IVs and to directly test possible violation of exogeneity of the IVs. I show that measurement error in smoking can lead to both under- and imprecise estimations of peer effects. Based on a refined measure of smoking, I find consistent evidence for peer effects on smoking. If a student's best friend smoked within the past 30 days, the student was about one fifth (as indicated by the OLS estimate) or 40 percentage points (as indicated by the IV estimate) more likely to smoke in the same time period. The findings are robust to a variety of robustness checks. I also show that sharing cigarettes may be a mechanism for peer effects on smoking. A 10% increase in the number of cigarettes smoked by a student's best friend is associated with about 4% increase in the number of cigarettes smoked by the student in the same time period. Copyright © 2014 Elsevier Inc. All rights reserved.

Assessing the Impact of Drug Use on Hospital Costs

PubMed Central

Stuart, Bruce C; Doshi, Jalpa A; Terza, Joseph V

2009-01-01

Objective To assess whether outpatient prescription drug utilization produces offsets in the cost of hospitalization for Medicare beneficiaries. Data Sources/Study Setting The study analyzed a sample (N=3,101) of community-dwelling fee-for-service U.S. Medicare beneficiaries drawn from the 1999 and 2000 Medicare Current Beneficiary Surveys. Study Design Using a two-part model specification, we regressed any hospital admission (part 1: probit) and hospital spending by those with one or more admissions (part 2: nonlinear least squares regression) on drug use in a standard model with strong covariate controls and a residual inclusion instrumental variable (IV) model using an exogenous measure of drug coverage as the instrument. Principal Findings The covariate control model predicted that each additional prescription drug used (mean=30) raised hospital spending by $16 (p<.001). The residual inclusion IV model prediction was that each additional prescription fill reduced hospital spending by $104 (p<.001). Conclusions The findings indicate that drug use is associated with cost offsets in hospitalization among Medicare beneficiaries, once omitted variable bias is corrected using an IV technique appropriate for nonlinear applications. PMID:18783453

Sport participation and subjective well-being: instrumental variable results from German survey data.

PubMed

Ruseski, Jane E; Humphreys, Brad R; Hallman, Kirstin; Wicker, Pamela; Breuer, Christoph

2014-02-01

A major policy goal of many ministries of sport and health is increased participation in sport to promote health. A growing literature is emerging about the benefits of sport participation on happiness. A challenge in establishing a link between sport participation and happiness is controlling for endogeneity of sport participation in the happiness equation. This study seeks to establish causal evidence of a relationship between sport participation and self reported happiness using instrumental variables (IV). IV estimates based on data from a 2009 population survey living in Rheinberg, Germany indicate that individuals who participate in sport have higher life happiness. The results suggest a U-shaped relationship between age and self-reported happiness. Higher income is associated with greater self-reported happiness, males are less happy than females, and single individuals are less happy than nonsingles. Since the results are IV, this finding is interpreted as a causal relationship between sport participation and subjective well-being (SWB). This broader impact of sport participation on general happiness lends support to the policy priority of many governments to increase sport participation at all levels of the general population.

The Use of Linear Instrumental Variables Methods in Health Services Research and Health Economics: A Cautionary Note

PubMed Central

Terza, Joseph V; Bradford, W David; Dismuke, Clara E

2008-01-01

Objective To investigate potential bias in the use of the conventional linear instrumental variables (IV) method for the estimation of causal effects in inherently nonlinear regression settings. Data Sources Smoking Supplement to the 1979 National Health Interview Survey, National Longitudinal Alcohol Epidemiologic Survey, and simulated data. Study Design Potential bias from the use of the linear IV method in nonlinear models is assessed via simulation studies and real world data analyses in two commonly encountered regression setting: (1) models with a nonnegative outcome (e.g., a count) and a continuous endogenous regressor; and (2) models with a binary outcome and a binary endogenous regressor. Principle Findings The simulation analyses show that substantial bias in the estimation of causal effects can result from applying the conventional IV method in inherently nonlinear regression settings. Moreover, the bias is not attenuated as the sample size increases. This point is further illustrated in the survey data analyses in which IV-based estimates of the relevant causal effects diverge substantially from those obtained with appropriate nonlinear estimation methods. Conclusions We offer this research as a cautionary note to those who would opt for the use of linear specifications in inherently nonlinear settings involving endogeneity. PMID:18546544

Estimating the effects of wages on obesity.

PubMed

Kim, DaeHwan; Leigh, John Paul

2010-05-01

To estimate the effects of wages on obesity and body mass. Data on household heads, aged 20 to 65 years, with full-time jobs, were drawn from the Panel Study of Income Dynamics for 2003 to 2007. The Panel Study of Income Dynamics is a nationally representative sample. Instrumental variables (IV) for wages were created using knowledge of computer software and state legal minimum wages. Least squares (linear regression) with corrected standard errors were used to estimate the equations. Statistical tests revealed both instruments were strong and tests for over-identifying restrictions were favorable. Wages were found to be predictive (P < 0.05) of obesity and body mass in regressions both before and after applying IVs. Coefficient estimates suggested stronger effects in the IV models. Results are consistent with the hypothesis that low wages increase obesity prevalence and body mass.

Comparative effectiveness of chemotherapy vs resection of the primary tumour as the initial treatment in older patients with Stage IV colorectal cancer.

PubMed

Mehta, H B; Vargas, G M; Adhikari, D; Dimou, F; Riall, T S

2017-06-01

The objectives were to determine trends in the use of chemotherapy as the initial treatment and to evaluate the comparative effectiveness of initial chemotherapy vs resection of the primary tumour on survival (intention-to-treat analysis) in Stage IV colorectal cancer (CRC). This cohort study used 2000-2011 data from the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database, including patients ≥ 66 years of age presenting with Stage IV CRC. Cox proportional hazards models and instrumental variable analysis were used to compare the effectiveness of chemotherapy as the initial treatment with resection of the primary tumour as the initial treatment, with 2-year survival as the end point. The use of chemotherapy as the first treatment increased over time, from 26.8% in 2001 to 46.9% in 2009 (P < 0.0001). The traditional Cox model showed that chemotherapy as the initial treatment was associated with a higher risk of mortality [hazard ratio (HR) = 1.35; 95% CI: 1.27-1.44]. When accounting for known and unknown confounders in an instrumental variable analysis, chemotherapy as the initial treatment suggested benefit on 2-year survival (HR = 0.68; 95% CI: 0.44-1.04); however, the association did not reach statistical significance. The study findings were similar in six subgroup analyses. The use of chemotherapy as the initial therapy for CRC increased substantially from 2001 to 2009. Instrumental variable analysis found that, compared with resection, chemotherapy as the initial treatment offers similar or better 2-year survival in patients with Stage IV CRC. Given the morbidity and mortality associated with colorectal resection in elderly patients, chemotherapy provides an option to patients who are not good candidates for resection. Colorectal Disease © 2017 The Association of Coloproctology of Great Britain and Ireland.

Characterization and evaluation of an aeolian-photovoltaic system in operation

NASA Astrophysics Data System (ADS)

Bonfatti, F.; Calzolari, P. U.; Cardinali, G. C.; Vivanti, G.; Zani, A.

Data management, analysis techniques and results of performance monitoring of a prototype combined photovoltaic (PV)-wind turbine farm power plant in northern Italy are reported. Emphasis is placed on the PV I-V characteristics and irradiance and cell temperatures. Automated instrumentation monitors and records meteorological data and generator variables such as voltages, currents, output, battery electrolyte temperature, etc. Analysis proceeds by automated selection of I-V data for specific intervals of the year when other variables can be treated as constants. The technique permits characterization of generator performance, adjusting the power plant set points for optimal output, and tracking performance degradation over time.

Introduction to meteorological measurements and data handling for solar energy applications. Task IV. Development of an isolation handbook and instrument package

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

None

The following are covered: the Sun and its radiation, solar radiation and atmospheric interaction, solar radiation measurement methods, spectral irradiance measurements of natural sources, the measurement of infrared radiation, the measurement of circumsolar radiation, some empirical properties of solar radiation and related parameters, duration of sunshine, and meteorological variables related to solar energy. Included in appendices are manufacturers and distributors of solar radiation measuring instruments and an approximate method for quality control of solar radiation instruments. (MHR)

The productivity of mental health care: an instrumental variable approach.

PubMed

Lu, Mingshan

1999-06-01

BACKGROUND: Like many other medical technologies and treatments, there is a lack of reliable evidence on treatment effectiveness of mental health care. Increasingly, data from non-experimental settings are being used to study the effect of treatment. However, as in a number of studies using non-experimental data, a simple regression of outcome on treatment shows a puzzling negative and significant impact of mental health care on the improvement of mental health status, even after including a large number of potential control variables. The central problem in interpreting evidence from real-world or non-experimental settings is, therefore, the potential "selection bias" problem in observational data set. In other words, the choice/quantity of mental health care may be correlated with other variables, particularly unobserved variables, that influence outcome and this may lead to a bias in the estimate of the effect of care in conventional models. AIMS OF THE STUDY: This paper addresses the issue of estimating treatment effects using an observational data set. The information in a mental health data set obtained from two waves of data in Puerto Rico is explored. The results using conventional models - in which the potential selection bias is not controlled - and that from instrumental variable (IV) models - which is what was proposed in this study to correct for the contaminated estimation from conventional models - are compared. METHODS: Treatment effectiveness is estimated in a production function framework. Effectiveness is measured as the improvement in mental health status. To control for the potential selection bias problem, IV approaches are employed. The essence of the IV method is to use one or more instruments, which are observable factors that influence treatment but do not directly affect patient outcomes, to isolate the effect of treatment variation that is independent of unobserved patient characteristics. The data used in this study are the first (1992-1993) and second (1993-1994) wave of the ongoing longitudinal study Mental Health Care Utilization Among Puerto Ricans, which includes information for an island-wide probability sample of over 3000 adults living in poor areas of Puerto Rico. The instrumental variables employed in this study are travel distance and health insurance sources. RESULTS: It is very noticeable that in this study, treatment effects were found to be negative in all conventional models (in some cases, highly significant). However, after the IV method was applied, the estimated marginal effects of treatment became positive. Sensitivity analysis partly supports this conclusion. According to the IV estimation results, treatment is productive for the group in most need of mental health care. However, estimations do not find strong enough evidence to demonstrate treatment effects on other groups with less or no need. The results in this paper also suggest an important impact of the following factors on the probability of improvement in mental health status: baseline mental health status, previous treatment, sex, marital status and education. DISCUSSION: The IV approach provides a practical way to reduce the selection bias due to the confounding of treatment with unmeasured variables. The limitation of this study is that the instruments explored did not perform well enough in some IV equations, therefore the predictive power remains questionable. The most challenging part of applying the IV approach is on finding "good" instruments which influence the choice/quantity of treatment yet do not introduce further bias by being directly correlated with treatment outcome. CONCLUSIONS: The results in this paper are supportive of the concerns on the credibility of evaluation results using observation data set when the endogeneity of the treatment variable is not controlled. Unobserved factors contribute to the downward bias in the conventional models. The IV approach is shown to be an appropriate method to reduce the selection bias for the group in most need for mental health care, which is also the group of most policy and treatment concern. IMPLICATIONS FOR HEALTH CARE PROVISION AND USE: The results of this work have implications for resource allocation in mental health care. Evidence is found that mental health care provided in Puerto Rico is productive, and is most helpful for persons in most need for mental health care. According to what estimated from the IV models, on the margin, receiving formal mental health care significantly increases the probability of obtaining a better mental health outcome by 19.2%, and one unit increase in formal treatment increased the probability of becoming healthier by 6.2% to 8.4%. Consistent with other mental health literature, an individual's baseline mental health status is found to be significantly related to the probability of improvement in mental health status: individuals with previous treatment history are less likely to improve. Among demographic factors included in the production function, being female, married, and high education were found to contribute to a higher probability of improvement. IMPLICATION FOR FURTHER RESEARCH: In order to provide accurate evidence of treatment effectiveness of medical technologies to support decision making, it is important that the selection bias be controlled as rigorously as possible when using information from a non-experimental setting. More data and a longer panel are also needed to provide more valid evidence. tion.

Insurance and the utilization of medical services.

PubMed

Meer, Jonathan; Rosen, Harvey S

2004-05-01

Most data sets indicate a positive correlation between having health insurance and utilizing health care services. Yet the direction of causality is not at all clear. If we observe a positive correlation between the utilization of health care services and insurance status, we do not know if this is because people who anticipate poor health buy more insurance (or take jobs with generous medical coverage), or because insurance lowers the cost of health care, increasing the quantity demanded. While a few attempts have been made to implement an instrumental variables (IV) strategy to deal with endogeneity, the instruments chosen have not been entirely convincing. In this paper we revisit the IV estimation of the reduced form relationships between insurance and health care utilization taking advantage of what we argue is a good instrument-the individual's self-employment status. Our main finding is that a positive and statistically significant effect of insurance continues to obtain even after instrumenting. Indeed, instrumental variables estimates of the impact of insurance on utilization of a variety of health care services are larger than their non-instrumented counterparts. The validity of this exercise depends on the extent to which self-employment status is a suitable instrument. To argue this case, we analyze panel data on transitions from wage-earning into self-employment and show that individuals who select into self-employment do not differ systematically from those who remain wage-earners with respect to either the utilization of health care or health status. While this finding does not prove that self-employment status is an appropriate instrument, it is encouraging that there appear to be no underlying differences that might lead to self-employment per se affecting health services utilization.

How Financial Literacy Affects Household Wealth Accumulation.

PubMed

Behrman, Jere R; Mitchell, Olivia S; Soo, Cindy K; Bravo, David

2012-05-01

This study isolates the causal effects of financial literacy and schooling on wealth accumulation using a new household dataset and an instrumental variables (IV) approach. Financial literacy and schooling attainment are both strongly positively associated with wealth outcomes in linear regression models, whereas the IV estimates reveal even more potent effects of financial literacy. They also indicate that the schooling effect only becomes positive when interacted with financial literacy. Estimated impacts are substantial enough to imply that investments in financial literacy could have large wealth payoffs.

How Financial Literacy Affects Household Wealth Accumulation

PubMed Central

Behrman, Jere R.; Mitchell, Olivia S.; Soo, Cindy K.; Bravo, David

2012-01-01

This study isolates the causal effects of financial literacy and schooling on wealth accumulation using a new household dataset and an instrumental variables (IV) approach. Financial literacy and schooling attainment are both strongly positively associated with wealth outcomes in linear regression models, whereas the IV estimates reveal even more potent effects of financial literacy. They also indicate that the schooling effect only becomes positive when interacted with financial literacy. Estimated impacts are substantial enough to imply that investments in financial literacy could have large wealth payoffs. PMID:23355747

Pensions and Household Wealth Accumulation

ERIC Educational Resources Information Center

Engelhardt, Gary V.; Kumar, Anil

2011-01-01

Economists have long suggested that higher private pension benefits "crowd out" other sources of household wealth accumulation. We exploit detailed information on pensions and lifetime earnings for older workers in the 1992 wave of the Health and Retirement Study and employ an instrumental-variable (IV) identification strategy to estimate…

Graphical Models for Quasi-Experimental Designs

ERIC Educational Resources Information Center

Steiner, Peter M.; Kim, Yongnam; Hall, Courtney E.; Su, Dan

2017-01-01

Randomized controlled trials (RCTs) and quasi-experimental designs like regression discontinuity (RD) designs, instrumental variable (IV) designs, and matching and propensity score (PS) designs are frequently used for inferring causal effects. It is well known that the features of these designs facilitate the identification of a causal estimand…

Duration of untreated psychosis and clinical outcomes of first episode psychosis: An observational and an instrumental variables analysis.

PubMed

Sullivan, Sarah A; Carroll, Robert; Peters, Tim J; Amos, Tim; Jones, Peter B; Marshall, Max; Birchwood, Max; Fowler, David; Johnson, Sonia; Fisher, Helen L; Major, Barnaby; Rahaman, Nikola; Joyce, John; Chamberlain-Kent, Nick; Lawrence, Jo; Moran, Paul; Tilling, Kate

2018-04-26

Duration of untreated psychosis (DUP) is considered as a key prognostic variable in psychosis. Yet, it is unclear whether a longer DUP causes worse outcomes or whether reported associations have alternative explanations. Data from 2 cohorts of patients with first episode psychosis were used (n = 2134). Measures of DUP were assessed at baseline and outcomes at 12 months. Regression models were used to investigate the associations between DUP and outcomes. We also investigated whether any associations were replicated using instrumental variables (IV) analysis to reduce the effect of residual confounding and measurement bias. There were associations between DUP per 1-year increase and positive psychotic symptoms (7.0% in symptom score increase 95% confidence interval (CI) 4.0%, 10.0%, P < .001), worse recovery (risk difference [RD] 0.78, 95%, CI 0.68, 0.83, P < .001) and worse global functioning (0.62 decrease in functioning score 95% CI -1.19, -0.04, P = .035). There was no evidence of an association with negative psychotic symptoms (1.0%, 95%, CI -2.0%, 5.0%, P = .455). The IV analysis showed weaker evidence of associations in the same direction between DUP per 1-year increase and positive psychotic symptoms, recovery and global functioning. However, there was evidence of an inverse association with negative psychotic symptoms (decrease of 15.0% in symptom score 95% CI -26.0%, -3.0%, P = .016). We have confirmed previous findings of a positive association between positive psychotic symptoms, global functioning and recovery and DUP using regression analysis. IV analysis shows some support for these findings. Future investigation using IV analysis should be repeated in large data sets. © 2018 John Wiley & Sons Australia, Ltd.

Assessing the role of insulin-like growth factors and binding proteins in prostate cancer using Mendelian randomization: Genetic variants as instruments for circulating levels.

PubMed

Bonilla, Carolina; Lewis, Sarah J; Rowlands, Mari-Anne; Gaunt, Tom R; Davey Smith, George; Gunnell, David; Palmer, Tom; Donovan, Jenny L; Hamdy, Freddie C; Neal, David E; Eeles, Rosalind; Easton, Doug; Kote-Jarai, Zsofia; Al Olama, Ali Amin; Benlloch, Sara; Muir, Kenneth; Giles, Graham G; Wiklund, Fredrik; Grönberg, Henrik; Haiman, Christopher A; Schleutker, Johanna; Nordestgaard, Børge G; Travis, Ruth C; Pashayan, Nora; Khaw, Kay-Tee; Stanford, Janet L; Blot, William J; Thibodeau, Stephen; Maier, Christiane; Kibel, Adam S; Cybulski, Cezary; Cannon-Albright, Lisa; Brenner, Hermann; Park, Jong; Kaneva, Radka; Batra, Jyotsna; Teixeira, Manuel R; Pandha, Hardev; Lathrop, Mark; Martin, Richard M; Holly, Jeff M P

2016-10-01

Circulating insulin-like growth factors (IGFs) and their binding proteins (IGFBPs) are associated with prostate cancer. Using genetic variants as instruments for IGF peptides, we investigated whether these associations are likely to be causal. We identified from the literature 56 single nucleotide polymorphisms (SNPs) in the IGF axis previously associated with biomarker levels (8 from a genome-wide association study [GWAS] and 48 in reported candidate genes). In ∼700 men without prostate cancer and two replication cohorts (N ∼ 900 and ∼9,000), we examined the properties of these SNPS as instrumental variables (IVs) for IGF-I, IGF-II, IGFBP-2 and IGFBP-3. Those confirmed as strong IVs were tested for association with prostate cancer risk, low (< 7) vs. high (≥ 7) Gleason grade, localised vs. advanced stage, and mortality, in 22,936 controls and 22,992 cases. IV analysis was used in an attempt to estimate the causal effect of circulating IGF peptides on prostate cancer. Published SNPs in the IGFBP1/IGFBP3 gene region, particularly rs11977526, were strong instruments for IGF-II and IGFBP-3, less so for IGF-I. Rs11977526 was associated with high (vs. low) Gleason grade (OR per IGF-II/IGFBP-3 level-raising allele 1.05; 95% CI: 1.00, 1.10). Using rs11977526 as an IV we estimated the causal effect of a one SD increase in IGF-II (∼265 ng/mL) on risk of high vs. low grade disease as 1.14 (95% CI: 1.00, 1.31). Because of the potential for pleiotropy of the genetic instruments, these findings can only causally implicate the IGF pathway in general, not any one specific biomarker. © 2016 UICC.

Power and instrument strength requirements for Mendelian randomization studies using multiple genetic variants.

PubMed

Pierce, Brandon L; Ahsan, Habibul; Vanderweele, Tyler J

2011-06-01

Mendelian Randomization (MR) studies assess the causality of an exposure-disease association using genetic determinants [i.e. instrumental variables (IVs)] of the exposure. Power and IV strength requirements for MR studies using multiple genetic variants have not been explored. We simulated cohort data sets consisting of a normally distributed disease trait, a normally distributed exposure, which affects this trait and a biallelic genetic variant that affects the exposure. We estimated power to detect an effect of exposure on disease for varying allele frequencies, effect sizes and samples sizes (using two-stage least squares regression on 10,000 data sets-Stage 1 is a regression of exposure on the variant. Stage 2 is a regression of disease on the fitted exposure). Similar analyses were conducted using multiple genetic variants (5, 10, 20) as independent or combined IVs. We assessed IV strength using the first-stage F statistic. Simulations of realistic scenarios indicate that MR studies will require large (n > 1000), often very large (n > 10,000), sample sizes. In many cases, so-called 'weak IV' problems arise when using multiple variants as independent IVs (even with as few as five), resulting in biased effect estimates. Combining genetic factors into fewer IVs results in modest power decreases, but alleviates weak IV problems. Ideal methods for combining genetic factors depend upon knowledge of the genetic architecture underlying the exposure. The feasibility of well-powered, unbiased MR studies will depend upon the amount of variance in the exposure that can be explained by known genetic factors and the 'strength' of the IV set derived from these genetic factors.

Mendelian randomization with Egger pleiotropy correction and weakly informative Bayesian priors.

PubMed

Schmidt, A F; Dudbridge, F

2017-12-15

The MR-Egger (MRE) estimator has been proposed to correct for directional pleiotropic effects of genetic instruments in an instrumental variable (IV) analysis. The power of this method is considerably lower than that of conventional estimators, limiting its applicability. Here we propose a novel Bayesian implementation of the MR-Egger estimator (BMRE) and explore the utility of applying weakly informative priors on the intercept term (the pleiotropy estimate) to increase power of the IV (slope) estimate. This was a simulation study to compare the performance of different IV estimators. Scenarios differed in the presence of a causal effect, the presence of pleiotropy, the proportion of pleiotropic instruments and degree of 'Instrument Strength Independent of Direct Effect' (InSIDE) assumption violation. Based on empirical plasma urate data, we present an approach to elucidate a prior distribution for the amount of pleiotropy. A weakly informative prior on the intercept term increased power of the slope estimate while maintaining type 1 error rates close to the nominal value of 0.05. Under the InSIDE assumption, performance was unaffected by the presence or absence of pleiotropy. Violation of the InSIDE assumption biased all estimators, affecting the BMRE more than the MRE method. Depending on the prior distribution, the BMRE estimator has more power at the cost of an increased susceptibility to InSIDE assumption violations. As such the BMRE method is a compromise between the MRE and conventional IV estimators, and may be an especially useful approach to account for observed pleiotropy. © The Author 2017. Published by Oxford University Press on behalf of the International Epidemiological Association.

Birth Spacing and Sibling Outcomes

ERIC Educational Resources Information Center

Buckles, Kasey S.; Munnich, Elizabeth L.

2012-01-01

Using the NLSY79 and NLSY79 Child and Young Adult Surveys, we investigate the effect of the age difference between siblings (spacing) on educational achievement. Because spacing may be endogenous, we use an instrumental variables strategy that exploits variation in spacing driven by miscarriages. The IV results indicate that a one-year increase in…

The Perceived Impact of Agricultural Advice in Ethiopia

ERIC Educational Resources Information Center

Hamilton, Alexander; Hudson, John

2017-01-01

Purpose: We examine the impact of advice given by extension agents to Ethiopian farmers, as perceived by the farmers themselves. Design/methodology/approach: Using survey data from 2014, we analyze the perceived impact of advice on farmers' incomes and crop yields. We use a bootstrapped instrumental variable (IV) estimator and the conditional…

Semiparametric methods for estimation of a nonlinear exposure-outcome relationship using instrumental variables with application to Mendelian randomization.

PubMed

Staley, James R; Burgess, Stephen

2017-05-01

Mendelian randomization, the use of genetic variants as instrumental variables (IV), can test for and estimate the causal effect of an exposure on an outcome. Most IV methods assume that the function relating the exposure to the expected value of the outcome (the exposure-outcome relationship) is linear. However, in practice, this assumption may not hold. Indeed, often the primary question of interest is to assess the shape of this relationship. We present two novel IV methods for investigating the shape of the exposure-outcome relationship: a fractional polynomial method and a piecewise linear method. We divide the population into strata using the exposure distribution, and estimate a causal effect, referred to as a localized average causal effect (LACE), in each stratum of population. The fractional polynomial method performs metaregression on these LACE estimates. The piecewise linear method estimates a continuous piecewise linear function, the gradient of which is the LACE estimate in each stratum. Both methods were demonstrated in a simulation study to estimate the true exposure-outcome relationship well, particularly when the relationship was a fractional polynomial (for the fractional polynomial method) or was piecewise linear (for the piecewise linear method). The methods were used to investigate the shape of relationship of body mass index with systolic blood pressure and diastolic blood pressure. © 2017 The Authors Genetic Epidemiology Published by Wiley Periodicals, Inc.

Semiparametric methods for estimation of a nonlinear exposure‐outcome relationship using instrumental variables with application to Mendelian randomization

PubMed Central

Staley, James R.

2017-01-01

ABSTRACT Mendelian randomization, the use of genetic variants as instrumental variables (IV), can test for and estimate the causal effect of an exposure on an outcome. Most IV methods assume that the function relating the exposure to the expected value of the outcome (the exposure‐outcome relationship) is linear. However, in practice, this assumption may not hold. Indeed, often the primary question of interest is to assess the shape of this relationship. We present two novel IV methods for investigating the shape of the exposure‐outcome relationship: a fractional polynomial method and a piecewise linear method. We divide the population into strata using the exposure distribution, and estimate a causal effect, referred to as a localized average causal effect (LACE), in each stratum of population. The fractional polynomial method performs metaregression on these LACE estimates. The piecewise linear method estimates a continuous piecewise linear function, the gradient of which is the LACE estimate in each stratum. Both methods were demonstrated in a simulation study to estimate the true exposure‐outcome relationship well, particularly when the relationship was a fractional polynomial (for the fractional polynomial method) or was piecewise linear (for the piecewise linear method). The methods were used to investigate the shape of relationship of body mass index with systolic blood pressure and diastolic blood pressure. PMID:28317167

Generalized Path Analysis and Generalized Simultaneous Equations Model for Recursive Systems with Responses of Mixed Types

ERIC Educational Resources Information Center

Tsai, Tien-Lung; Shau, Wen-Yi; Hu, Fu-Chang

2006-01-01

This article generalizes linear path analysis (PA) and simultaneous equations models (SiEM) to deal with mixed responses of different types in a recursive or triangular system. An efficient instrumental variable (IV) method for estimating the structural coefficients of a 2-equation partially recursive generalized path analysis (GPA) model and…

Does Expert Advice Improve Educational Choice?

PubMed Central

2015-01-01

This paper reports evidence that an individual meeting with a study counselor at high school significantly improves the quality of choice of tertiary educational field, as self-assessed 18 months after graduation from college. To address endogeneity, we explore the variation in study counseling practices between schools as an instrumental variable (IV). Following careful scrutiny of the validity of the IV, our results indicate a significant and positive influence of study counseling on the quality of educational choice, foremost among males and those with low educated parents. The overall result is stable across a number of robustness checks. PMID:26692388

Use of the TAT in the assessment of DSM-IV cluster B personality disorders.

PubMed

Ackerman, S J; Clemence, A J; Weatherill, R; Hilsenroth, M J

1999-12-01

The Social Cognition and Object Relations Scale (SCORS), developed by Western, Lohr, Silk, Kerber, and Goodrich (1985), is a diagnostic instrument used to assess an array of psychological functioning by using clinical narratives such as the Thematic Apperception Test (TAT; Murray, 1943) stories. This study investigated the utility of the SCORS to differentiate between Diagnostic and Statistical Manual of Mental Disorders (4th ed. [DSM-IV]; American Psychiatric Association, 1994) antisocial personality disorder (ANPD), borderline personality disorder (BPD), narcissistic personality disorder (NPD), and Cluster C personality disorder (CPD). A sample of 58 patients was separated into four groups: ANPD (n = 9), BPD (n = 21; 18 with a primary BPD diagnosis and 3 with prominent borderline traits who met 4 of the 5 DSM-IV criteria necessary for a BPD diagnosis), NPD (n = 16; 8 with a primary NPD diagnosis and 8 with prominent narcissistic traits who met 4 of the 5 DSM-IV criteria necessary for a NPD diagnosis), and CPD (n = 12). These groups were then compared on the 8 SCORS variables by using 5 TAT cards (1, 2, 3BM, 4, and 13MF). Spearman-Brown correction for 2-way mixed effects model of reliability for the 8 SCORS variables ranged from .70 to .95. The results of categorical and dimensional analyses indicate that (a) SCORS variables can be used to differentiate ANPD, BPD, and NPD; (b) the BPD group scored significantly lower (greater maladjustment) than did the CPD group on certain variables; (c) the BPD group scored significantly lower (greater maladjustment) than did the NPD group on all 8 SCORS variables; (d) the ANPD group scored significantly lower than did the NPD group on certain variables; (e) certain variables were found to be empirically related to the total number of DSM-IV ANPD, BPD, and NPD criteria; and (f) certain variables were found to be empirically related to Minnesota Multiphasic Personality Inventory-2 (MMPI-2; Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1989) Personality disorder scales. The results of this study are discussed in terms of clinical utility, conceptual, and theoretical implications.

Getting a Job Is Only Half the Battle: Maternal Job Loss and Child Classroom Behavior in Low-Income Families

ERIC Educational Resources Information Center

Hill, Heather D.; Morris, Pamela A.; Castells, Nina; Walker, Jessica Thornton

2011-01-01

This study uses data from an experimental employment program and instrumental variables (IV) estimation to examine the effects of maternal job loss on child classroom behavior. Random assignment to the treatment at one of three program sites is an exogenous predictor of employment patterns. Cross-site variation in treatment-control differences is…

Effects of wages on smoking decisions of current and past smokers.

PubMed

Du, Juan; Leigh, J Paul

2015-08-01

We used longitudinal data and instrumental variables (IVs) in a prospective design to test for the causal effects of wages on smoking prevalence among current and past smokers. Nationally representative U.S. data were drawn from the 1999-2009 waves of the Panel Study of Income Dynamics. Our overall sample was restricted to full time employed persons, aged 21-65 years. We excluded part time workers and youths because smoking and wage correlations would be complicated by labor supply decisions. We excluded adult never smokers because people rarely begin smoking after the age of 20 years. IVs were created with state-level minimum wages and unionization rates. We analyzed subsamples of men, women, the less educated, the more educated, quitters, and backsliders. Validity and strength of instruments within the IV analysis were conducted with the Sargan-Hansen J statistic and F tests. We found some evidence that low wages lead to more smoking in the overall sample and substantial evidence for men, persons with high school educations or less (<13 years of schooling), and quitters. Results indicated that 10% increases in wages lead to 5.5 and 4.6 percentage point decreases in smoking for men and the less educated; they also increased the average chance of quitting among base-year smokers from 17.0% to 20.4%. Statistical tests suggested that IVs were strong and valid in most samples. Subjects' other family income, including spouses' wages, was entered as a control variable. Increases in an individual's wages, independent of other income, decreased the prevalence of smoking among current and past smokers. Copyright © 2015 Elsevier Inc. All rights reserved.

Sodium citrate vacuum tubes validation: preventing preanalytical variability in routine coagulation testing.

PubMed

Lima-Oliveira, Gabriel; Lippi, Giuseppe; Salvagno, Gian Luca; Montagnana, Martina; Picheth, Geraldo; Guidi, Gian Cesare

2013-04-01

Sometimes in-vitro diagnostic devices (e.g. blood collection tubes) are not validated before use or when the producer's brand is changed. The aim of this study was to validate five brands of sodium citrate vacuum tubes. Blood specimens from 50 volunteers were collected in five different tube brands (I: Venosafe, II: VACUETTE, III: BD Vacutainer, IV: LABOR IMPORT and V: S-Monovette). Routine coagulation tests [activated partial thromboplastin time (aPTT), prothrombin time (PT), and fibrinogen (FIB)] were performed on ACL TOP instrument using HemosIL reagents. The significance of the differences between samples was assessed by paired Student's t-test, set at P < 0.005. Significant differences were observed for: PT when comparing I vs. II, I vs. III, I vs. V, II vs. III, II vs. IV, II vs. V, III vs. IV, III vs. V and IV vs. V; aPTT when comparing I vs. II, I vs. III, I vs. IV, II vs. IV, III vs. IV and IV vs. V. No differences were observed among brands for FIB determination. We suggest that every laboratory management should both standardize the procedures and frequently evaluate the quality of in-vitro diagnostic devices.

The Effect of Private Insurance on the Health of Older, Working Age Adults: Evidence from the Health and Retirement Study

PubMed Central

Dor, Avi; Sudano, Joseph; Baker, David W

2006-01-01

Objective Primarily, to determine if the presence of private insurance leads to improved health status, as measured by a survey-based health score. Secondarily, to explore sensitivity of estimates to adjustments for endogeneity. The study focuses on adults in late middle age who are nearing entry into Medicare. Data Sources The analysis file is drawn from the Health and Retirement Study, a national survey of relatively older adults in the labor force. The dependent variable, an index of 5 health outcome items, was obtained from the 1996 survey. Independent variables were obtained from the 1992 survey. State-level instrumental variables were obtained from the Area Resources File and the TAXSIM file. The final sample consists of 9,034 individuals of which 1,540 were uninsured. Study Design Estimation addresses endogeneity of the insurance participation decision in health score regressions. In addition to ordinary least squares (OLS), two models are tested: an instrumental variables (IV) model, and a model with endogenous treatment effects due to Heckman (1978). Insurance participation and health behaviors enter with a lag to allow their effects to dissipate over time. Separate regressions were run for groupings of chronic conditions. Principal Findings The OLS model results in statistically significant albeit small effects of insurance on the computed health score, but the results may be downward biased. Adjusting for endogeneity using state-level instrumental variables yields up to a six-fold increase in the insurance effect. Results are consistent across IV and treatment effects models, and for major groupings of medical conditions. The insurance effect appears to be in the range of about 2–11 percent. There appear to be no significant differences in the insurance effect for subgroups with and without major chronic conditions. Conclusions Extending insurance coverage to working age adults may result in improved health. By conjecture, policies aimed at expanding coverage to this population may lead to improved health at retirement and entry to Medicare, potentially leading to savings. However, further research is needed to determine whether similar results are found when alternative measures of overall health or health scores are used. Future research should also explore the use of alternative instrumental variables. Preliminary results provide no justification for targeting certain subgroups with susceptibility to certain chronic conditions rather than broad policy interventions. PMID:16704511

Waist circumference, body mass index, and employment outcomes.

PubMed

Kinge, Jonas Minet

2017-07-01

Body mass index (BMI) is an imperfect measure of body fat. Recent studies provide evidence in favor of replacing BMI with waist circumference (WC). Hence, I investigated whether or not the association between fat mass and employment status vary by anthropometric measures. I used 15 rounds of the Health Survey for England (1998-2013), which has measures of employment status in addition to measured height, weight, and WC. WC and BMI were entered as continuous variables and obesity as binary variables defined using both WC and BMI. I used multivariate models controlling for a set of covariates. The association of WC with employment was of greater magnitude than the association between BMI and employment. I reran the analysis using conventional instrumental variables methods. The IV models showed significant impacts of obesity on employment; however, they were not more pronounced when WC was used to measure obesity, compared to BMI. This means that, in the IV models, the impact of fat mass on employment did not depend on the measure of fat mass.

Migraine headache and labor market outcomes.

PubMed

Rees, Daniel I; Sabia, Joseph J

2015-06-01

While migraine headache can be physically debilitating, no study has attempted to estimate its effects on labor market outcomes. Using data drawn from the National Longitudinal Study of Adolescent Health, we estimate the effect of being diagnosed with migraine headache on labor force participation, hours worked, and wages. Ordinary least squares (OLS) estimates suggest that migraines are associated with reduced labor force participation and lower wages among females. A negative association between migraine headache and the wages of female respondents is also obtained using an instrumental variables (IV) approach, although the IV estimates are imprecise relative to the OLS estimates. Copyright © 2014 John Wiley & Sons, Ltd.

Psychosocial Assessment of Self-Harm Patients and Risk of Repeat Presentation: An Instrumental Variable Analysis Using Time of Hospital Presentation.

PubMed

Carroll, Robert; Metcalfe, Chris; Steeg, Sarah; Davies, Neil M; Cooper, Jayne; Kapur, Nav; Gunnell, David

2016-01-01

Clinical guidelines have recommended psychosocial assessment of self-harm patients for years, yet estimates of its impact on the risk of repeat self-harm vary. Assessing the association of psychosocial assessment with risk of repeat self-harm is challenging due to the effects of confounding by indication. We analysed data from a cohort study of 15,113 patients presenting to the emergency departments of three UK hospitals to investigate the association of psychosocial assessment with risk of repeat hospital presentation for self-harm. Time of day of hospital presentation was used as an instrument for psychosocial assessment, attempting to control for confounding by indication. Conventional regression analysis suggested psychosocial assessment was not associated with risk of repeat self-harm within 12 months (Risk Difference (RD) 0.00 95% confidence interval (95%CI) -0.01 to 0.02). In contrast, IV analysis suggested risk of repeat self-harm was reduced by 18% (RD -0.18, 95%CI -0.32 to -0.03) in those patients receiving a psychosocial assessment. However, the instrument of time of day did not remove all potential effects of confounding by indication, suggesting the IV effect estimate may be biased. We found that psychosocial assessments reduce risk of repeat self-harm. This is in-line with other non-randomised studies based on populations in which allocation to assessment was less subject to confounding by indication. However, as our instrument did not fully balance important confounders across time of day, the IV effect estimate should be interpreted with caution.

Do genetic risk scores for body mass index predict risk of phobic anxiety? Evidence for a shared genetic risk factor

PubMed Central

Walter, Stefan; Glymour, M. Maria; Koenen, Karestan; Liang, Liming; Tchetgen Tchetgen, Eric J; Cornelis, Marilyn; Chang, Shun-Chiao; Rewak, Marissa; Rimm, Eric; Kawachi, Ichiro; Kubzansky, Laura D.

2015-01-01

Background Obesity and anxiety are often linked but the direction of effects is not clear. Methods Using genetic instrumental variable (IV) analyses in a sample of 5911 female participants from the Nurses´ Health Study (NHS, initiated in 1976) and 3697 male participants from the Health Professional Follow-up Study (HPFS, initiated in 1986), we aim to determine whether obesity increases symptoms of phobic anxiety. FTO, MC4R, and a genetic risk score (GRS) based on 32 single nucleotide polymorphisms that significantly predict body mass index (BMI), were used as instrumental variables. “Functional” GRS corresponding with specific biological pathways that shape BMI (adipogenesis, appetite, and cardio-pulmonary), were considered. Phobic anxiety as measured by the Crown Crisp Experimental Index (CCI) in 2004 in NHS and 2000 in HPFS was the main outcome. Results In observational analysis, a one unit higher BMI was associated with higher phobic anxiety symptoms (women NHS: beta=0.05; 95% Confidence Interval (CI): 0.030 – 0.068 and men, HPFS, beta = 0.04; 95% CI: 0.016 – 0.071). IV analyses showed that BMI instrumented by FTO was associated with higher phobic anxiety symptoms (p = 0.005) but BMI instrumented by GRS was not (p=0.256). Functional GRS scores showed heterogeneous, non-significant effects of BMI on phobic anxiety symptoms. Conclusions Our findings do not provide conclusive evidence in favor of the hypothesis that higher BMI leads to higher levels of phobic anxiety, but rather suggest that genes that influence obesity, in particular FTO, may have direct effects on phobic anxiety, i.e., that obesity and phobic anxiety may share common genetic determinants. PMID:25065638

Do genetic risk scores for body mass index predict risk of phobic anxiety? Evidence for a shared genetic risk factor.

PubMed

Walter, S; Glymour, M M; Koenen, K; Liang, L; Tchetgen Tchetgen, E J; Cornelis, M; Chang, S-C; Rewak, M; Rimm, E; Kawachi, I; Kubzansky, L D

2015-01-01

Obesity and anxiety are often linked but the direction of effects is not clear. Using genetic instrumental variable (IV) analyses in 5911 female participants from the Nurses' Health Study (NHS, initiated 1976) and 3697 male participants from the Health Professional Follow-up Study (HPFS, initiated 1986), we aimed to determine whether obesity increases symptoms of phobic anxiety. As instrumental variables we used the fat mass and obesity-associated (FTO) gene, the melanocortin 4 receptor (MC4R) gene and a genetic risk score (GRS) based on 32 single nucleotide polymorphisms (SNPs) that significantly predict body mass index (BMI). 'Functional' GRSs corresponding with specific biological pathways that shape BMI (adipogenesis, appetite and cardiopulmonary) were considered. The main outcome was phobic anxiety measured by the Crown Crisp Index (CCI) in 2004 in the NHS and in 2000 in the HPFS. In observational analysis, a 1-unit higher BMI was associated with higher phobic anxiety symptoms [women: β = 0.05, 95% confidence interval (CI) 0.030-0.068; men: β = 0.04, 95% CI 0.016-0.071). IV analyses showed that BMI was associated with higher phobic anxiety symptoms in the FTO-instrumented analysis (p = 0.005) but not in the GRS-instrumented analysis (p = 0.256). Functional GRSs showed heterogeneous, non-significant effects of BMI on phobic anxiety symptoms. Our findings do not provide conclusive evidence in favor of the hypothesis that higher BMI leads to higher levels of phobic anxiety, but rather suggest that genes that influence obesity, in particular FTO, may have direct effects on phobic anxiety, and hence that obesity and phobic anxiety may share common genetic determinants.

VizieR Online Data Catalog: OGLE: Gaia South Ecliptic Pole Field (Soszynski+, 2012)

NASA Astrophysics Data System (ADS)

Soszynski, I.; Udalski, A.; Poleski, R.; Kozlowski, S.; Wyrzykowski, L.; Pietrukowicz, P.; Szymanski, M. K.; Kubiak, M.; Pietrzynski, G.; Ulaczyk, K.; Skowron, J.

2013-03-01

We present a comprehensive analysis of the Gaia South Ecliptic Pole (GSEP) field, 5.3 square degrees area around the South Ecliptic Pole on the outskirts of the LMC, based on the data collected during the fourth phase of the Optical Gravitational Lensing Experiment, OGLE-IV. The GSEP field will be observed during the commissioning phase of the ESA Gaia space mission for testing and calibrating the Gaia instruments. We provide the photometric maps of the GSEP region containing the mean VI photometry of all detected stellar objects and their equatorial coordinates. We show the quality and completeness of the OGLE-IV photometry and color-magnitude diagrams of this region. We conducted an extensive search for variable stars in the GSEP field leading to the discovery of 6789 variable stars. In this sample we found 132 classical Cepheids, 686 RR Lyr type stars, 2819 long-period, and 1377 eclipsing variables. Several objects deserving special attention were also selected, including a new classical Cepheid in a binary eclipsing system. (9 data files).

Volumetric analysis of hand, reciprocating and rotary instrumentation techniques in primary molars using spiral computed tomography: An in vitro comparative study.

PubMed

Jeevanandan, Ganesh; Thomas, Eapen

2018-01-01

This present study was conducted to analyze the volumetric change in the root canal space and instrumentation time between hand files, hand files in reciprocating motion, and three rotary files in primary molars. One hundred primary mandibular molars were randomly allotted to one of the five groups. Instrumentation was done using Group I; nickel-titanium (Ni-Ti) hand file, Group II; Ni-Ti hand files in reciprocating motion, Group III; Race rotary files, Group IV; prodesign pediatric rotary files, and Group V; ProTaper rotary files. The mean volumetric changes were assessed using pre- and post-operative spiral computed tomography scans. Instrumentation time was recorded. Statistical analysis to access intergroup comparison for mean canal volume and instrumentation time was done using Bonferroni-adjusted Mann-Whitney test and Mann-Whitney test, respectively. Intergroup comparison of mean canal volume showed statistically significant difference between Groups II versus IV, Groups III versus V, and Groups IV versus V. Intergroup comparison of mean instrumentation time showed statistically significant difference among all the groups except Groups IV versus V. Among the various instrumentation techniques available, rotary instrumentation is the considered to be the better instrumentation technique for canal preparation in primary teeth.

Comparative analysis of efficacy and cleaning ability of hand and rotary devices for gutta-percha removal in root canal retreatment: an in vitro study.

PubMed

Reddy, Narender; Admala, Shilpa Reddy; Dinapadu, Sainath; Pasari, Srikanth; Reddy, Manoranjan P; Rao, M S Rama

2013-07-01

To evaluate the efficacy and cleaning ability of Hedstrom files, and ProTaper retreatment instruments in removing gutta-percha from root canals with and without xylene as solvent. Sixty extracted single rooted human teeth were selected and decoronated, straight access established working length determined 1 mm short of canal, chemomechanical preparation done and obturated with guttapercha and AH plus sealer. Samples were stored for 1 week in humidifier divided into four groups of 15 teeth each. • Group I: Hedstrom files without xylene. • Group II: Hedstrom files with xylene. • Group III: ProTaper retreatment instruments without xylene. • Group IV: ProTaper retreatment instruments with xylene. and the following criteria were assessed - Time taken for initial plunge of instrument into guttapercha. - Time taken for complete removal of gutta-percha to reach working length - Ability of H files and ProTaper retreatment files with/ without xylene to remove gutta-percha in coronal, middle and apical 1/3 of canal. The teeth were grooved in labiolingual cross section, observed under a steromicroscope and scored according to gutta-percha debris left in the canal. Results were evaluated using ANOVA test and multiple comparisons done using Scheffe test. The least time to reach working length was found with group IV followed by groups III, II and group I respectively. Also the fastest way to remove maximum gutta-percha was group IV followed by groups III, II, and I respectively with a statistically significant difference among all groups. Apical 1/3 has more amount of remaining gutta-percha debris than middle and coronal 1/3 in all groups. The amount of gutta-percha debris in apical 1/3 was least in group IV followed by groups III, II and I respectively. The better performance of ProTaper rotary instruments has been attributed to their special flute design which tends to pull gutta-percha coronally directing it toward orifice. Also the movements of engine driven instruments produce frictional heat which plasticises gutta-percha and aids in easy removal. Apical third of root canals showed more guttapercha debris compared to coronal and middle 1/3 and has been attributed to the greater anatomic variability and difficulty of instrumentation in the apical area. The existence of deep groves and depressions on dentine walls in this apical 1/3 make them less instrumented areas as it did be difficult to direct the file against the extreme root canal wall. The fastest technique to remove gutta-percha and the shortest time to reach working length was observed with ProTaper retreatment instruments with xylene followed by ProTaper retreatment files without xylene and Hedstrom files without xylene. After instrumentation for removal of gutta-percha, apical third was found to have more debris compared to coronal and middle 1/3 of the root canal.

The cross-cultural generalizability of Axis-II constructs: an evaluation of two personality disorder assessment instruments in the People's Republic of China.

PubMed

Yang, J; McCrae, R R; Costa, P T; Yao, S; Dai, X; Cai, T; Gao, B

2000-01-01

We examined the reliability, cross-instrument validity, and factor structure of Chinese adaptations of the Personality Diagnostic Questionnaire (PDQ-4+; N = 1,926) and Personality Disorders Interview (PDI-IV; N = 525) in psychiatric patients. Comparisons with data from Western countries suggest that the psychometric properties of these two instruments are comparable across cultures. Low to modest agreement between the PDQ-4+ and PDI-IV was observed for both dimensional and categorical personality disorder evaluations. When the PDI-IV was used as the diagnostic standard, the PDQ-4+ showed higher sensitivity than specificity, and higher negative predictive power than positive predictive power. Factor analyses of both instruments replicated the four-factor structure O'Connor and Dyce (1998) found in Western samples. Results suggested that conceptions and measures of DSM-IV personality disorders are cross-culturally generalizable to Chinese psychiatric populations.

The Optical Gravitational Lensing Experiment. Gaia South Ecliptic Pole Field as Seen by OGLE-IV

NASA Astrophysics Data System (ADS)

Soszyński, I.; Udalski, A.; Poleski, R.; Kozłowski, S.; Wyrzykowski, Ł.; Pietrukowicz, P.; Szymański, M. K.; Kubiak, M.; Pietrzyński, G.; Ulaczyk, K.; Skowron, J.

2012-09-01

We present a comprehensive analysis of the Gaia South Ecliptic Pole (GSEP) field, 5.3 square degrees area around the South Ecliptic Pole on the outskirts of the LMC, based on the data collected during the fourth phase of the Optical Gravitational Lensing Experiment, OGLE-IV. The GSEP field will be observed during the commissioning phase of the ESA Gaia space mission for testing and calibrating the Gaia instruments. We provide the photometric maps of the GSEP region containing the mean VI photometry of all detected stellar objects and their equatorial coordinates. We show the quality and completeness of the OGLE-IV photometry and color-magnitude diagrams of this region. We conducted an extensive search for variable stars in the GSEP field leading to the discovery of 6789 variable stars. In this sample we found 132 classical Cepheids, 686 RR Lyr type stars, 2819 long-period, and 1377 eclipsing variables. Several objects deserving special attention were also selected, including a new classical Cepheid in a binary eclipsing system. To provide empirical data for the Gaia Science Alert system we also conducted a search for optical transients. We discovered two firm type Ia supernovae and nine additional supernova candidates. To facilitate future Gaia supernovae detections we prepared a list of more than 1900 galaxies to redshift about 0.1 located in the GSEP field. Finally, we present the results of astrometric study of the GSEP field. With the 26 months time base of the presented here OGLE-IV data, proper motions of stars could be detected with the accuracy reaching 2 mas/yr. Astrometry allowed to distinguish galactic foreground variable stars detected in the GSEP field from LMC objects and to discover about 50 high proper motion stars (proper motion ≥ 100 mas/yr). Among them three new nearby white dwarfs were found. All data presented in this paper are available to the astronomical community from the OGLE Internet archive.

Wernher von Braun

NASA Image and Video Library

1959-03-01

In this photo, Director of the U.S. Army Ballistic Missile Agency's (ABMA) Development Operations Division, Dr. Wernher von Braun, and Director of Missile Firing Division, Dr. Kurt Debus, are shown with unidentified individuals, discussing two components that would make up the Pioneer IV Lunar Probe. The mercury batteries (left) were used to power the radio transmitter, cosmic radiation counter and other instruments in Pioneer IV. The conical shroud placed over the instruments of Pioneer IV was plated with gold to improve conductivity. The metal surface also served as the anterna for the probe's instruments signaling back to the Earth receiving stations.

Measuring the Impact of Financial Intermediation: Linking Contract Theory to Econometric Policy Evaluation *

PubMed Central

Townsend, Robert M.; Urzua, Sergio S.

2010-01-01

We study the impact that financial intermediation can have on productivity through the alleviation of credit constraints in occupation choice and/or an improved allocation of risk, using both static and dynamic structural models as well as reduced form OLS and IV regressions. Our goal in this paper is to bring these two strands of the literature together. Even though, under certain assumptions, IV regressions can recover accurately the true model-generated local average treatment effect, these are quantitatively different, in order of magnitude and even sign, from other policy impact parameters (e.g., ATE and TT). We also show that laying out clearly alternative models can guide the search for instruments. On the other hand adding more margins of decision, i.e., occupation choice and intermediation jointly, or adding more periods with promised utilities as key state variables, as in optimal multi-period contracts, can cause the misinterpretation of IV as the causal effect of interest. PMID:20436953

Obtaining systematic teacher reports of disruptive behavior disorders utilizing DSM-IV.

PubMed

Wolraich, M L; Feurer, I D; Hannah, J N; Baumgaertel, A; Pinnock, T Y

1998-04-01

This study examines the psychometric properties of the Vanderbilt AD/HD Diagnostic Teacher Rating Scale (VADTRS) and provides preliminary normative data from a large, geographically defined population. The VADTRS consists of the complete list of DSM-IV AD/HD symptoms, a screen for other disruptive behavior disorders, anxiety and depression, and ratings of academic and classroom behavior performance. Teachers in one suburban county completed the scale for their students during 2 consecutive years. Statistical methods included (a) exploratory and confirmatory latent variable analyses of item data, (b) evaluation of the internal consistency of the latent dimensions, (c) evaluation of latent structure concordance between school year samples, and (d) preliminary evaluation of criterion-related validity. The instrument comprises four behavioral dimensions and two performance dimensions. The behavioral dimensions were concordant between school years and were consistent with a priori DSM-IV diagnostic criteria. Correlations between latent dimensions and relevant, known disorders or problems varied from .25 to .66.

Early Teen Marriage and Future Poverty

PubMed Central

DAHL, GORDON B.

2010-01-01

Both early teen marriage and dropping out of high school have historically been associated with a variety of negative outcomes, including higher poverty rates throughout life. Are these negative outcomes due to preexisting differences, or do they represent the causal effect of marriage and schooling choices? To better understand the true personal and societal consequences, in this article, I use an instrumental variables (IV) approach that takes advantage of variation in state laws regulating the age at which individuals are allowed to marry, drop out of school, and begin work. The baseline IV estimate indicates that a woman who marries young is 31 percentage points more likely to live in poverty when she is older. Similarly, a woman who drops out of school is 11 percentage points more likely to be poor. The results are robust to a variety of alternative specifications and estimation methods, including limited information maximum likelihood (LIML) estimation and a control function approach. While grouped ordinary least squares (OLS) estimates for the early teen marriage variable are also large, OLS estimates based on individual-level data are small, consistent with a large amount of measurement error. PMID:20879684

Early teen marriage and future poverty.

PubMed

Dahl, Gordon B

2010-08-01

Both early teen marriage and dropping out of high school have historically been associated with a variety of negative outcomes, including higher poverty rates throughout life. Are these negative outcomes due to preexisting differences, or do they represent the causal effect of marriage and schooling choices? To better understand the true personal and societal consequences, in this article, I use an instrumental variables (IV) approach that takes advantage of variation in state laws regulating the age at which individuals are allowed to marry, drop out of school, and begin work. The baseline IV estimate indicates that a woman who marries young is 31 percentage points more likely to live in poverty when she is older. Similarly, a woman who drops out of school is 11 percentage points more likely to be poor. The results are robust to a variety of alternative specifications and estimation methods, including limited information maximum likelihood (LIML) estimation and a control function approach. While grouped ordinary least squares (OLS) estimates for the early teen marriage variable are also large, OLS estimates based on individual-level data are small, consistent with a large amount of measurement error

Comparative Analysis of Inpatient Costs for Obstetrics and Gynecology Surgery Patients Treated With IV Acetaminophen and IV Opioids Versus IV Opioid-only Analgesia for Postoperative Pain.

PubMed

Hansen, Ryan N; Pham, An T; Lovelace, Belinda; Balaban, Stela; Wan, George J

2017-10-01

Recovery from obstetrics and gynecology (OB/GYN) surgery, including hysterectomy and cesarean section delivery, aims to restore function while minimizing hospital length of stay (LOS) and medical expenditures. Our analyses compare OB/GYN surgery patients who received combination intravenous (IV) acetaminophen and IV opioid analgesia with those who received IV opioid-only analgesia and estimate differences in LOS, hospitalization costs, and opioid consumption. We performed a retrospective analysis of the Premier Database between January 2009 and June 2015, comparing OB/GYN surgery patients who received postoperative pain management with combination IV acetaminophen and IV opioids with those who received only IV opioids starting on the day of surgery and continuing up to the second postoperative day. We performed instrumental variable 2-stage least-squares regressions controlling for patient and hospital covariates to compare the LOS, hospitalization costs, and daily opioid doses (morphine equivalent dose) of IV acetaminophen recipients with that of opioid-only analgesia patients. We identified 225 142 OB/GYN surgery patients who were eligible for our study of whom 89 568 (40%) had been managed with IV acetaminophen and opioids. Participants averaged 36 years of age and were predominantly non-Hispanic Caucasians (60%). Multivariable regression models estimated statistically significant differences in hospitalization cost and opioid use with IV acetaminophen associated with $484.4 lower total hospitalization costs (95% CI = -$760.4 to -$208.4; P = 0.0006) and 8.2 mg lower daily opioid use (95% CI = -10.0 to -6.4), whereas the difference in LOS was not significant, at -0.09 days (95% CI = -0.19 to 0.01; P = 0.07). Compared with IV opioid-only analgesia, managing post-OB/GYN surgery pain with the addition of IV acetaminophen is associated with decreased hospitalization costs and reduced opioid use.

Getting a Job is Only Half the Battle: Maternal Job Loss and Child Classroom Behavior in Low-Income Families

PubMed Central

Hill, Heather D.; Morris, Pamela A.; Castells, Nina; Walker, Jessica Thornton

2011-01-01

This study uses data from an experimental employment program and instrumental variables (IV) estimation to examine the effects of maternal job loss on child classroom behavior. Random assignment to the treatment at one of three program sites is an exogenous predictor of employment patterns. Cross-site variation in treatment-control differences is used to identify the effects of employment levels and transitions. Under certain assumptions, this method controls for unobserved correlates of job loss and child well-being, as well as measurement error and simultaneity. IV estimates suggest that maternal job loss sharply increases problem behavior but has neutral effects on positive social behavior. Current employment programs concentrate primarily on job entry, but these findings point to the importance of promoting job stability for workers and their children. PMID:22162901

Insurance disruption due to spousal Medicare transitions: implications for access to care and health care utilization for women approaching age 65.

PubMed

Schumacher, Jessica R; Smith, Maureen A; Liou, Jinn-Ing; Pandhi, Nancy

2009-06-01

To assess whether a husband's Medicare transition leads to insurance disruptions for his wife that impact her perceived access to care, health care utilization, or health status. Respondents were married women under age 65 from the 2003-2005 round of the Wisconsin Longitudinal Study (N=655). Instrumental variable (IV) linear and IV-probit analyses provided unbiased estimates of the effect of an insurance disruption on study outcomes. The instrument was the husband's age: (1) women with husbands who transitioned to Medicare within the previous year (age 65-66); (2) women with husbands who did not transition (60

HST FUV monitoring of TW Hya

NASA Astrophysics Data System (ADS)

Guenther, Hans; Brickhouse, N. S.; Dupree, A. K.; Luna, G.; Schneider, P. C.; Wolk, S. J.

2014-01-01

Classical T Tauri stars (CTTS) show strong, broad and asymmetric FUV emission lines. Neither the width, nor the line profile is understood. Likely, different mechanisms influence the line profile; the best candidates are accretion, winds and stellar activity. We monitored the C IV 1548/1550 Å doublet in the nearby, bright CTTS TW Hya to correlate it with i) the cool wind, as seen in COS NUV Mg II line profiles, ii) the photometric period from joint ground-based monitoring, iii) the accretion rate as determined from the UV continuum and iv) the Ha line profile from independent ground-based observations. The observations span 10 orbits distributed over a few weeks to cover the typical time scales of stellar rotation, accretion and winds. On short time scales (seconds) the variability in the data is compatible with counting statistics when we take certain instrumental effects (the detector dead-time fraction increases when the wavelength calibration lamps are switched on). This rules out any type of coherent accretion shock fluctuation as predicted in some simulations. On longer time scales (days) variability of a factor of 3 in the continuum and similarly massive changes in the line shape are seen. The ratio of the two lines of the doublet indicates that the lines are optically thick, calling into question the idea that the blue-shifted components of the C IV lines are formed in the pre-shock region.

The Stratospheric Aerosol and Gas Experiment (SAGE) IV Pathfinder

NASA Astrophysics Data System (ADS)

Hill, C. A.; Damadeo, R. P.; Gasbarre, J. F.

2017-12-01

Stratospheric ozone has been the subject of observation and research for decades. Measurements from satellites provided data on the initial decline in the late 1970s and early 1980s that supported the adoption of the Montreal Protocol to current observations hinting at potential recovery. Adequate determination of that recovery requires continuous and, in the case of multiple instruments, overlapping data records. However, most current satellite systems are well beyond their expected lifetimes and thus, with only a few "younger" instruments available, we look towards the future of satellite observations of stratospheric ozone to develop the Stratospheric Aerosol and Gas Experiment (SAGE) IV Pathfinder. The SAGE IV Pathfinder project will develop and validate a technology demonstration that will pave the way for a future SAGE IV mission. Utilizing solar occultation imaging, SAGE IV will be capable of measuring ozone, aerosol, and other trace gas species with the same quality as previous SAGE instruments but with greatly improved pointing knowledge. Furthermore, current technological advancements allow SAGE IV to fit within a CubeSat framework and make use of commercial hardware, significantly reducing the size and cost when compared with traditional missions and enabling sustainability of future measurements.

Validation of the Portuguese DSM-IV-MR-J.

PubMed

Calado, Filipa; Alexandre, Joana; Griffiths, Mark D

2016-01-01

Youth problem gambling is viewed as an emergent public health issue in many countries, and is also an emerging area of public concern in Portugal. However, there is currently no Portuguese instrument that focuses specifically on the measurement of problem gambling among young people. Consequently, the present study aimed to validate the DSM-IV-MR-J for use among Portuguese adolescents and to examine its' psychometric properties. A cross-cultural adaption of this instrument to the Portuguese language was performed using the translation and back translation method. The final version of the instrument was administered to 753 Portuguese high school and first year college students. The findings revealed an acceptable internal reliability and replicated the one-factor structure of this scale. Based on these findings, the Portuguese DSM-IV-MR-J appears to be a valid and reliable instrument, and provides a much needed psychometric tool for the development of more research on youth gambling in Portugal.

Preparing the MAX IV storage rings for timing-based experiments

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

Stråhlman, C., E-mail: Christian.Strahlman@maxlab.lu.se; Olsson, T., E-mail: Teresia.Olsson@maxlab.lu.se; Leemann, S. C.

2016-07-27

Time-resolved experimental techniques are increasingly abundant at storage ring facilities. Recent developments in accelerator technology and beamline instrumentation allow for simultaneous operation of high-intensity and timing-based experiments. The MAX IV facility is a state-of-the-art synchrotron light source in Lund, Sweden, that will come into operation in 2016. As many storage ring facilities are pursuing upgrade programs employing strong-focusing multibend achromats and passive harmonic cavities (HCs) in high-current operation, it is of broad interest to study the accelerator and instrumentation developments required to enable timing-based experiments at such machines. In particular, the use of hybrid filling modes combined with pulse pickingmore » by resonant excitation or pseudo single bunch has shown promising results. These methods can be combined with novel beamline instrumentation, such as choppers and instrument gating. In this paper we discuss how these techniques can be implemented and employed at MAX IV.« less

Effect of a community intervention programme promoting social interactions on functional disability prevention for older adults: propensity score matching and instrumental variable analyses, JAGES Taketoyo study.

PubMed

Hikichi, Hiroyuki; Kondo, Naoki; Kondo, Katsunori; Aida, Jun; Takeda, Tokunori; Kawachi, Ichiro

2015-09-01

The efficacy of promoting social interactions to improve the health of older adults is not fully established due to residual confounding and selection bias. The government of Taketoyo town, Aichi Prefecture, Japan, developed a resident-centred community intervention programme called 'community salons', providing opportunities for social interactions among local older residents. To evaluate the impact of the programme, we conducted questionnaire surveys for all older residents of Taketoyo. We carried out a baseline survey in July 2006 (prior to the introduction of the programme) and assessed the onset of functional disability during March 2012. We analysed the data of 2421 older people. In addition to the standard Cox proportional hazard regression, we conducted Cox regression with propensity score matching (PSM) and an instrumental variable (IV) analysis, using the number of community salons within a radius of 350 m from the participant's home as an instrument. In the 5 years after the first salon was launched, the salon participants showed a 6.3% lower incidence of functional disability compared with non-participants. Even adjusting for sex, age, equivalent income, educational attainment, higher level activities of daily living and depression, the Cox adjusted HR for becoming disabled was 0.49 (95% CI 0.33 to 0.72). Similar results were observed using PSM (HR 0.52, 95% CI 0.33 to 0.83) and IV-Cox analysis (HR 0.50, 95% CI 0.34 to 0.74). A community health promotion programme focused on increasing social interactions among older adults may be effective in preventing the onset of disability. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Hospital ownership and performance: evidence from stroke and cardiac treatment in Taiwan.

PubMed

Lien, Hsien-Ming; Chou, Shin-Yi; Liu, Jin-Tan

2008-09-01

This paper compares program expenditure and treatment quality of stroke and cardiac patients between 1997 and 2000 across hospitals of various ownership types in Taiwan. Because Taiwan implemented national health insurance in 1995, the analysis is immune from problems arising from the complex setting of the U.S. health care market, such as segmentation of insurance status or multiple payers. Because patients may select admitted hospitals based on their observed and unobserved characteristics, we employ instrument variable (IV) estimation to account for the endogeneity of ownership status. Results of IV estimation find that patients admitted to non-profit hospitals receive better quality care, either measured by 1- or 12-month mortality rates. In terms of treatment expenditure, our results indicate no difference between non-profits and for-profits index admission expenditures, and at most 10% higher long-term expenditure for patients admitted to non-profits than to for-profits.

Effect of nursing home ownership on hospitalization of long-stay residents: an instrumental variables approach

PubMed Central

Grabowski, David C.; Feng, Zhanlian; Rahman, Momotazur; Mor, Vincent

2014-01-01

Hospitalizations among nursing home residents are frequent, expensive, and often associated with further deterioration of resident condition. The literature indicates that a substantial fraction of admissions is potentially preventable and that nonprofit nursing homes are less likely to hospitalize their residents. However, the correlation between ownership and hospitalization might reflect unobserved resident differences rather than a causal relationship. Using national minimum data set assessments linked with Medicare claims, we use a national cohort of long-stay residents who were newly admitted to nursing homes within an 18-month period spanning January 1, 2004 and June 30, 2005. After instrumenting for ownership status, we found that IV estimates of the effect of nonprofit ownership on hospitalization are at least as large as the non-instrumented effects, indicating that selection bias does not explain the observed relationship. We also found evidence suggesting the lower rate of hospitalizations among nonprofits was due to a different threshold for transfer. PMID:24234287

Effect of nursing home ownership on hospitalization of long-stay residents: an instrumental variables approach.

PubMed

Hirth, Richard A; Grabowski, David C; Feng, Zhanlian; Rahman, Momotazur; Mor, Vincent

2014-03-01

Hospitalizations among nursing home residents are frequent, expensive, and often associated with further deterioration of resident condition. The literature indicates that a substantial fraction of admissions is potentially preventable and that nonprofit nursing homes are less likely to hospitalize their residents. However, the correlation between ownership and hospitalization might reflect unobserved resident differences rather than a causal relationship. Using national minimum data set assessments linked with Medicare claims, we use a national cohort of long-stay residents who were newly admitted to nursing homes within an 18-month period spanning January 1, 2004 and June 30, 2005. After instrumenting for ownership status, we found that IV estimates of the effect of nonprofit ownership on hospitalization are at least as large as the non-instrumented effects, indicating that selection bias does not explain the observed relationship. We also found evidence suggesting the lower rate of hospitalizations among nonprofits was due to a different threshold for transfer.

Remotely Operating a Fourier Transform Spectrometer for Atmospheric Remote Sensing

NASA Technical Reports Server (NTRS)

Blavier, J.-F.; Toon, G. C.; Sen, B.

2000-01-01

This paper describes how the MkIV instrument was adapted for remote operation from the Barcroft site, where the harsh winter conditions make access difficult. Some of the main technical challenges will be discussed including, (i) operation from solar panels and batteries, (ii) cooling the detectors with LN2, (iii) instrument control and monitoring over a cellular phone, and (iv) data storage, processing and analysis. Finally, MkIV spectra measured from Barcroft and compared with those measured from JPL to highlight the advantages of the higher altitude site.

Investigating the reasons of variability in Si IV and C IV broad absorption line troughs of quasars

NASA Astrophysics Data System (ADS)

Stathopoulos, Dimitrios; Lyratzi, Evangelia; Danezis, Emmanuel; Antoniou, Antonios; Tzimeas, Dimitrios

2017-09-01

In this paper we analyze the C IV and Si IV broad absorption troughs of two BALQSOs (J101056.69+355833.3, J114548.38+393746.6) to the individual components they consist of. By analyzing a BAL trough to its components we have the advantage to study the variations of the individual absorbing systems in the line of sight and not just the variations of the whole absorption trough or the variations of selected portions of BAL troughs exhibiting changes. We find that the velocity shifts and FWHMs (Full Width at Half Maximum) of the individual components do not vary between an interval of six years. All variable components show changes in the optical depths at line centers which are manifested as variations in the EW (Equivalent Width) of the components. In both BALQSOs, over corresponding velocities, Si IV has higher incidence of variability than C IV. From our analysis, evidence is in favour of different covering fractions between C IV and Si IV. Finally, although most of our results favour the crossing cloud scenario as the cause of variability, there is also strong piece of evidence indicating changing ionization as the source of variability. Thus, a mixed situation where both physical mechanisms contribute to BAL variability is the most possible scenario.

Comparison of variability in pork carcass composition and quality between barrows and gilts.

PubMed

Overholt, M F; Arkfeld, E K; Mohrhauser, D A; King, D A; Wheeler, T L; Dilger, A C; Shackelford, S D; Boler, D D

2016-10-01

Pigs ( = 8,042) raised in 8 different barns representing 2 seasons (cold and hot) and 2 production focuses (lean growth and meat quality) were used to characterize variability of carcass composition and quality traits between barrows and gilts. Data were collected on 7,684 pigs at the abattoir. Carcass characteristics, subjective loin quality, and fresh ham face color (muscles) were measured on a targeted 100% of carcasses. Fresh belly characteristics, boneless loin weight, instrumental loin color, and ultimate loin pH measurements were collected from 50% of the carcasses each slaughter day. Adipose tissue iodine value (IV), 30-min loin pH, LM slice shear force, and fresh ham muscle characteristic measurements were recorded on 10% of carcasses each slaughter day. Data were analyzed using the MIXED procedure of SAS as a 1-way ANOVA in a randomized complete block design with 2 levels (barrows and gilts). Barn (block), marketing group, production focus, and season were random variables. A 2-variance model was fit using the REPEATED statement of the MIXED procedure, grouped by sex for analysis of least squares means. Homogeneity of variance was tested on raw data using Levene's test of the GLM procedure. Hot carcass weight of pigs (94.6 kg) in this study was similar to U.S. industry average HCW (93.1 kg). Therefore, these data are representative of typical U.S. pork carcasses. There was no difference ( ≥ 0.09) in variability of HCW or loin depth between barrow and gilt carcasses. Back fat depth and estimated carcass lean were more variable ( ≤ 0.0001) and IV was less variable ( = 0.05) in carcasses from barrows than in carcasses from gilts. Fresh belly weight and thickness were more variable ( ≤ 0.01) for bellies of barrows than bellies of gilts, but there was no difference in variability for belly length, width, or flop distance ( ≥ 0.06). Fresh loin subjective color was less variable ( < 0.01) and subjective marbling was more variable ( < 0.0001) in loins from barrows than in those from gilts, but there were no differences ( ≥ 0.08) in variability for any other loin traits or fresh ham traits. Overall, traits associated with carcass fatness, including back fat depth, belly thickness, and marbling, but not IV, were more variable in carcasses from barrows than in carcasses from gilts, whereas minimal differences in variability existed between carcasses of barrows and carcasses of gilts for traits associated with carcass muscling and lean quality.

The Choice of Screening Instrument Matters: The Case of Problematic Cannabis Use Screening in Spanish Population of Adolescents

PubMed Central

Domingo-Salvany, Antónia; Barrio Anta, Gregorio; Sánchez Mañez, Amparo; Llorens Aleixandre, Noelia; Brime Beteta, Begoña; Vicente, Julián

2013-01-01

The aim of this study was to examine the feasibility of problem cannabis use screening instruments administration within wide school surveys, their psychometric properties, overlaps, and relationships with other variables. Students from 7 Spanish regions, aged 14–18, who attended secondary schools were sampled by two-stage cluster sampling (net sample 14,589). Standardized, anonymous questionnaire including DSM-IV cannabis abuse criteria, Cannabis Abuse Screening Test (CAST), and Severity of Dependence Scale (SDS) was self-completed with paper and pencil in the selected classrooms. Data was analysed using classical psychometric theory, bivariate tests, and multinomial logistic regression analysis. Not responding to instruments' items (10.5–12.3%) was associated with reporting less frequent cannabis use. The instruments overlapped partially, with 16.1% of positives being positive on all three. SDS was more likely to identify younger users with lower frequency of use who thought habitual cannabis use posed a considerable problem. CAST positivity was associated with frequent cannabis use and related problems. It is feasible to use short psychometric scales in wide school surveys, but one must carefully choose the screening instrument, as different instruments identify different groups of users. These may correspond to different types of problematic cannabis use; however, measurement bias seems to play a role too. PMID:25969832

The dependence of C IV broad absorption line properties on accompanying Si IV and Al III absorption: relating quasar-wind ionization levels, kinematics, and column densities

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

Filiz Ak, N.; Brandt, W. N.; Schneider, D. P.

2014-08-20

We consider how the profile and multi-year variability properties of a large sample of C IV Broad Absorption Line (BAL) troughs change when BALs from Si IV and/or Al III are present at corresponding velocities, indicating that the line of sight intercepts at least some lower ionization gas. We derive a number of observational results for C IV BALs separated according to the presence or absence of accompanying lower ionization transitions, including measurements of composite profile shapes, equivalent width (EW), characteristic velocities, composite variation profiles, and EW variability. We also measure the correlations between EW and fractional-EW variability for Cmore » IV, Si IV, and Al III. Our measurements reveal the basic correlated changes between ionization level, kinematics, and column density expected in accretion-disk wind models; e.g., lines of sight including lower ionization material generally show deeper and broader C IV troughs that have smaller minimum velocities and that are less variable. Many C IV BALs with no accompanying Si IV or Al III BALs may have only mild or no saturation.« less

Causal relationship between obesity and vitamin D status: bi-directional Mendelian randomization analysis of multiple cohorts.

PubMed

Vimaleswaran, Karani S; Berry, Diane J; Lu, Chen; Tikkanen, Emmi; Pilz, Stefan; Hiraki, Linda T; Cooper, Jason D; Dastani, Zari; Li, Rui; Houston, Denise K; Wood, Andrew R; Michaëlsson, Karl; Vandenput, Liesbeth; Zgaga, Lina; Yerges-Armstrong, Laura M; McCarthy, Mark I; Dupuis, Josée; Kaakinen, Marika; Kleber, Marcus E; Jameson, Karen; Arden, Nigel; Raitakari, Olli; Viikari, Jorma; Lohman, Kurt K; Ferrucci, Luigi; Melhus, Håkan; Ingelsson, Erik; Byberg, Liisa; Lind, Lars; Lorentzon, Mattias; Salomaa, Veikko; Campbell, Harry; Dunlop, Malcolm; Mitchell, Braxton D; Herzig, Karl-Heinz; Pouta, Anneli; Hartikainen, Anna-Liisa; Streeten, Elizabeth A; Theodoratou, Evropi; Jula, Antti; Wareham, Nicholas J; Ohlsson, Claes; Frayling, Timothy M; Kritchevsky, Stephen B; Spector, Timothy D; Richards, J Brent; Lehtimäki, Terho; Ouwehand, Willem H; Kraft, Peter; Cooper, Cyrus; März, Winfried; Power, Chris; Loos, Ruth J F; Wang, Thomas J; Järvelin, Marjo-Riitta; Whittaker, John C; Hingorani, Aroon D; Hyppönen, Elina

2013-01-01

Obesity is associated with vitamin D deficiency, and both are areas of active public health concern. We explored the causality and direction of the relationship between body mass index (BMI) and 25-hydroxyvitamin D [25(OH)D] using genetic markers as instrumental variables (IVs) in bi-directional Mendelian randomization (MR) analysis. We used information from 21 adult cohorts (up to 42,024 participants) with 12 BMI-related SNPs (combined in an allelic score) to produce an instrument for BMI and four SNPs associated with 25(OH)D (combined in two allelic scores, separately for genes encoding its synthesis or metabolism) as an instrument for vitamin D. Regression estimates for the IVs (allele scores) were generated within-study and pooled by meta-analysis to generate summary effects. Associations between vitamin D scores and BMI were confirmed in the Genetic Investigation of Anthropometric Traits (GIANT) consortium (n = 123,864). Each 1 kg/m(2) higher BMI was associated with 1.15% lower 25(OH)D (p = 6.52×10⁻²⁷). The BMI allele score was associated both with BMI (p = 6.30×10⁻⁶²) and 25(OH)D (-0.06% [95% CI -0.10 to -0.02], p = 0.004) in the cohorts that underwent meta-analysis. The two vitamin D allele scores were strongly associated with 25(OH)D (p≤8.07×10⁻⁵⁷ for both scores) but not with BMI (synthesis score, p = 0.88; metabolism score, p = 0.08) in the meta-analysis. A 10% higher genetically instrumented BMI was associated with 4.2% lower 25(OH)D concentrations (IV ratio: -4.2 [95% CI -7.1 to -1.3], p = 0.005). No association was seen for genetically instrumented 25(OH)D with BMI, a finding that was confirmed using data from the GIANT consortium (p≥0.57 for both vitamin D scores). On the basis of a bi-directional genetic approach that limits confounding, our study suggests that a higher BMI leads to lower 25(OH)D, while any effects of lower 25(OH)D increasing BMI are likely to be small. Population level interventions to reduce BMI are expected to decrease the prevalence of vitamin D deficiency.

Polarization Measurements on SUMI's TVLS Gratings

NASA Technical Reports Server (NTRS)

Kobayashi, K.; West, E. A.; Davis, J. M.; Gary, G. A.

2007-01-01

We present measurements of toroidal variable-line-space (TVLS) gratings for the Solar Ultraviolet Magnetograph Investigation (SUMI), currently being developed an the National Space Science and Technology Center (NSSTC). SUMI zs a spectro-polarimeter designed no measure magnetic fields in the solar chromosphere by observing two UV emission lines sensitive to magnetic fields, the C-IV line at 155nm and the Mg-II line at 280nm. The instrument uses a pair of TVLS gratings, to observe both linear polarizations simultaneously. Efficiency measurements were done on bare aluminum gratings and MgF2 coated gratings, at both linear polarizations.

Does childhood schooling affect old age memory or mental status? Using state schooling laws as natural experiments.

PubMed

Glymour, M M; Kawachi, I; Jencks, C S; Berkman, L F

2008-06-01

The association between schooling and old age cognitive outcomes such as memory disorders is well documented but, because of the threat of reverse causation, controversy persists over whether education affects old age cognition. Changes in state compulsory schooling laws (CSL) are treated as natural experiments (instruments) for estimating the effect of education on memory and mental status among the elderly. Changes in CSL predict changes in average years of schooling completed by children who are affected by the new laws. These educational differences are presumably independent of innate individual characteristics such as IQ. CSL-induced changes in education were used to obtain instrumental variable (IV) estimates of education's effect on memory (n = 10,694) and mental status (n = 9751) for white, non-Hispanic US-born Health and Retirement Survey participants born between 1900 and 1947 who did not attend college. After adjustment for sex, birth year, state of birth and state characteristics, IV estimates of education's effect on memory were large and statistically significant. IV estimates for mental status had very wide confidence intervals, so it was not possible to draw meaningful conclusions about the effect of education on this outcome. Increases in mandatory schooling lead to improvements in performance on memory tests many decades after school completion. These analyses condition on individual states, so differences in memory outcomes associated with CSL changes cannot be attributed to differences between states. Although unmeasured state characteristics that changed contemporaneously with CSL might account for these results, unobserved genetic variation is unlikely to do so.

Does childhood schooling affect old age memory or mental status? Using state schooling laws as natural experiments

PubMed Central

Glymour, M M; Kawachi, I; Jencks, C S; Berkman, L F

2009-01-01

Background The association between schooling and old age cognitive outcomes such as memory disorders is well documented but, because of the threat of reverse causation, controversy persists over whether education affects old age cognition. Changes in state compulsory schooling laws (CSL) are treated as natural experiments (instruments) for estimating the effect of education on memory and mental status among the elderly. Changes in CSL predict changes in average years of schooling completed by children who are affected by the new laws. These educational differences are presumably independent of innate individual characteristics such as IQ. Methods CSL-induced changes in education were used to obtain instrumental variable (IV) estimates of education’s effect on memory (n = 10 694) and mental status (n = 9751) for white, non-Hispanic US-born Health and Retirement Survey participants born between 1900 and 1947 who did not attend college. Results After adjustment for sex, birth year, state of birth and state characteristics, IV estimates of education’s effect on memory were large and statistically significant. IV estimates for mental status had very wide confidence intervals, so it was not possible to draw meaningful conclusions about the effect of education on this outcome. Conclusions Increases in mandatory schooling lead to improvements in performance on memory tests many decades after school completion. These analyses condition on individual states, so differences in memory outcomes associated with CSL changes cannot be attributed to differences between states. Although unmeasured state characteristics that changed contemporaneously with CSL might account for these results, unobserved genetic variation is unlikely to do so. PMID:18477752

Overcoming bias in estimating the volume-outcome relationship.

PubMed

Tsai, Alexander C; Votruba, Mark; Bridges, John F P; Cebul, Randall D

2006-02-01

To examine the effect of hospital volume on 30-day mortality for patients with congestive heart failure (CHF) using administrative and clinical data in conventional regression and instrumental variables (IV) estimation models. The primary data consisted of longitudinal information on comorbid conditions, vital signs, clinical status, and laboratory test results for 21,555 Medicare-insured patients aged 65 years and older hospitalized for CHF in northeast Ohio in 1991-1997. The patient was the primary unit of analysis. We fit a linear probability model to the data to assess the effects of hospital volume on patient mortality within 30 days of admission. Both administrative and clinical data elements were included for risk adjustment. Linear distances between patients and hospitals were used to construct the instrument, which was then used to assess the endogeneity of hospital volume. When only administrative data elements were included in the risk adjustment model, the estimated volume-outcome effect was statistically significant (p=.029) but small in magnitude. The estimate was markedly attenuated in magnitude and statistical significance when clinical data were added to the model as risk adjusters (p=.39). IV estimation shifted the estimate in a direction consistent with selective referral, but we were unable to reject the consistency of the linear probability estimates. Use of only administrative data for volume-outcomes research may generate spurious findings. The IV analysis further suggests that conventional estimates of the volume-outcome relationship may be contaminated by selective referral effects. Taken together, our results suggest that efforts to concentrate hospital-based CHF care in high-volume hospitals may not reduce mortality among elderly patients.

Maternal employment and childhood overweight in Germany.

PubMed

Meyer, Sophie-Charlotte

2016-12-01

A widespread finding among studies from the US and the UK is that maternal employment is correlated with an increased risk of child overweight, even in a causal manner, whereas studies from other countries obtain less conclusive results. As evidence for Germany is still scarce, the purpose of this study is to identify the effect of maternal employment on childhood overweight in Germany using two sets of representative micro data. We further explore potential underlying mechanisms that might explain this relationship. In order to address the selection into maternal full-time employment, we use an instrumental variable strategy exploiting the number of younger siblings in the household as an instrument. While the OLS models suggest that maternal full-time employment is related to a 5 percentage point higher probability of the child to be overweight, IV estimates indicate a 25 percentage points higher overweight probability due to maternal full-time employment. Exploring various possible pathways, we find that maternal full-time employment promotes unhealthy dietary and activity behavior which might explain the positive effect of maternal employment on child overweight to some extent. Although there are limitations to our IV approach, several sensitivity analyses confirm the robustness of our findings. Copyright © 2016 Elsevier B.V. All rights reserved.

Performance of the RAPS4/RAPS4-QF for DSM-5 compared to DSM-IV alcohol use disorders in the general population: Data from the 2000-2010 National Alcohol Surveys.

PubMed

Cherpitel, Cheryl J; Ye, Yu

2015-06-01

A number of relatively short screening instruments have been developed for identifying alcohol use disorders (AUD), but performance has been evaluated against the standard Diagnostic and Statistical Manual of Mental and Behavior Disorders (DSM) criteria, and it is not known how screening instruments may perform based on the newly formulated DSM-5 criteria, which is a radical departure from previous versions of the DSM. Analyzed here is the performance of the RAPS4/RAPS4-QF against DSM-5 criteria for AUD compared to DSM-IV dependence and abuse criteria. Sensitivity and specificity are analyzed in a merged sample of 21,386 respondents from three National Alcohol Surveys of the U.S. general population (2000, 2005, 2010). Sensitivity of the RAPS4 was lower for DSM-5 AUD (62.5%) than for DSM-IV dependence (88%), while the RAPS4-QF was higher for DSM-5 AUD (90.3%) than for DSM-IV abuse (81.3%), or abuse/dependence (85.8%), while maintaining good specificity (84%). Sensitivity of the RAPS4-QF was higher for males (92%) compared to females (86.6%) and highest for whites (93.8%) followed by Hispanics (84.2%) and blacks (82.4%). Screening instruments may not perform similarly for DSM-5 as for DSM-IV AUD, and data here suggest the RAPS4-QF may be a good instrument choice for identifying those meeting criteria for DSM-5 AUD. These data also suggest the need for additional research and a similar evaluation of other commonly used screening instruments for DSM-5 AUD. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Internal variability of a dynamically downscaled climate over North America

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

Wang, Jiali; Bessac, Julie; Kotamarthi, Rao

This study investigates the internal variability (IV) of a regional climate model, and considers the impacts of horizontal resolution and spectral nudging on the IV. A 16-member simulation ensemble was conducted using the Weather Research Forecasting model for three model configurations. Ensemble members included simulations at spatial resolutions of 50 km and 12 km without spectral nudging and simulations at a spatial resolution of 12 km with spectral nudging. All the simulations were generated over the same domain, which covered much of North America. The degree of IV was measured as the spread between the individual members of the ensemblemore » during the integration period. The IV of the 12 km simulation with spectral nudging was also compared with a future climate change simulation projected by the same model configuration. The variables investigated focus on precipitation and near-surface air temperature. While the IVs show a clear annual cycle with larger values in summer and smaller values in winter, the seasonal IV is smaller for a 50-km spatial resolution than for a 12-km resolution when nudging is not applied. Applying a nudging technique to the 12-km simulation reduces the IV by a factor of two, and produces smaller IV than the simulation at 50 km without nudging. Applying a nudging technique also changes the geographic distributions of IV in all examined variables. The IV is much smaller than the inter-annual variability at seasonal scales for regionally averaged temperature and precipitation. The IV is also smaller than the projected changes in air-temperature for the mid- and late 21st century. However, the IV is larger than the projected changes in precipitation for the mid- and late 21st century.« less

Internal variability of a dynamically downscaled climate over North America

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

Wang, Jiali; Bessac, Julie; Kotamarthi, Rao

This study investigates the internal variability (IV) of a regional climate model, and considers the impacts of horizontal resolution and spectral nudging on the IV. A 16-member simulation ensemble was conducted using the Weather Research Forecasting model for three model configurations. Ensemble members included simulations at spatial resolutions of 50 and 12 km without spectral nudging and simulations at a spatial resolution of 12 km with spectral nudging. All the simulations were generated over the same domain, which covered much of North America. The degree of IV was measured as the spread between the individual members of the ensemble duringmore » the integration period. The IV of the 12 km simulation with spectral nudging was also compared with a future climate change simulation projected by the same model configuration. The variables investigated focus on precipitation and near-surface air temperature. While the IVs show a clear annual cycle with larger values in summer and smaller values in winter, the seasonal IV is smaller for a 50-km spatial resolution than for a 12-km resolution when nudging is not applied. Applying a nudging technique to the 12-km simulation reduces the IV by a factor of two, and produces smaller IV than the simulation at 50 km without nudging. Applying a nudging technique also changes the geographic distributions of IV in all examined variables. The IV is much smaller than the inter-annual variability at seasonal scales for regionally averaged temperature and precipitation. The IV is also smaller than the projected changes in air-temperature for the mid- and late twenty-first century. However, the IV is larger than the projected changes in precipitation for the mid- and late twenty-first century.« less

Internal variability of a dynamically downscaled climate over North America

NASA Astrophysics Data System (ADS)

Wang, Jiali; Bessac, Julie; Kotamarthi, Rao; Constantinescu, Emil; Drewniak, Beth

2018-06-01

This study investigates the internal variability (IV) of a regional climate model, and considers the impacts of horizontal resolution and spectral nudging on the IV. A 16-member simulation ensemble was conducted using the Weather Research Forecasting model for three model configurations. Ensemble members included simulations at spatial resolutions of 50 and 12 km without spectral nudging and simulations at a spatial resolution of 12 km with spectral nudging. All the simulations were generated over the same domain, which covered much of North America. The degree of IV was measured as the spread between the individual members of the ensemble during the integration period. The IV of the 12 km simulation with spectral nudging was also compared with a future climate change simulation projected by the same model configuration. The variables investigated focus on precipitation and near-surface air temperature. While the IVs show a clear annual cycle with larger values in summer and smaller values in winter, the seasonal IV is smaller for a 50-km spatial resolution than for a 12-km resolution when nudging is not applied. Applying a nudging technique to the 12-km simulation reduces the IV by a factor of two, and produces smaller IV than the simulation at 50 km without nudging. Applying a nudging technique also changes the geographic distributions of IV in all examined variables. The IV is much smaller than the inter-annual variability at seasonal scales for regionally averaged temperature and precipitation. The IV is also smaller than the projected changes in air-temperature for the mid- and late twenty-first century. However, the IV is larger than the projected changes in precipitation for the mid- and late twenty-first century.

Internal variability of a dynamically downscaled climate over North America

NASA Astrophysics Data System (ADS)

Wang, Jiali; Bessac, Julie; Kotamarthi, Rao; Constantinescu, Emil; Drewniak, Beth

2017-09-01

This study investigates the internal variability (IV) of a regional climate model, and considers the impacts of horizontal resolution and spectral nudging on the IV. A 16-member simulation ensemble was conducted using the Weather Research Forecasting model for three model configurations. Ensemble members included simulations at spatial resolutions of 50 and 12 km without spectral nudging and simulations at a spatial resolution of 12 km with spectral nudging. All the simulations were generated over the same domain, which covered much of North America. The degree of IV was measured as the spread between the individual members of the ensemble during the integration period. The IV of the 12 km simulation with spectral nudging was also compared with a future climate change simulation projected by the same model configuration. The variables investigated focus on precipitation and near-surface air temperature. While the IVs show a clear annual cycle with larger values in summer and smaller values in winter, the seasonal IV is smaller for a 50-km spatial resolution than for a 12-km resolution when nudging is not applied. Applying a nudging technique to the 12-km simulation reduces the IV by a factor of two, and produces smaller IV than the simulation at 50 km without nudging. Applying a nudging technique also changes the geographic distributions of IV in all examined variables. The IV is much smaller than the inter-annual variability at seasonal scales for regionally averaged temperature and precipitation. The IV is also smaller than the projected changes in air-temperature for the mid- and late twenty-first century. However, the IV is larger than the projected changes in precipitation for the mid- and late twenty-first century.

The Sloan Digital Sky Survey Reverberation Mapping Project: The C IV Blueshift, Its Variability, and Its Dependence Upon Quasar Properties

NASA Astrophysics Data System (ADS)

Sun, Mouyuan; Xue, Yongquan; Richards, Gordon T.; Trump, Jonathan R.; Shen, Yue; Brandt, W. N.; Schneider, D. P.

2018-02-01

We use the multi-epoch spectra of 362 quasars from the Sloan Digital Sky Survey Reverberation Mapping project to investigate the dependence of the blueshift of C IV relative to Mg II on quasar properties. We confirm that high-blueshift sources tend to have low C IV equivalent widths (EWs), and that the low-EW sources span a range of blueshift. Other high-ionization lines, such as He II, also show similar blueshift properties. The ratio of the line width (measured as both the full width at half maximum and the velocity dispersion) of C IV to that of Mg II increases with blueshift. Quasar variability enhances the connection between the C IV blueshift and quasar properties (e.g., EW). The variability of the Mg II line center (i.e., the wavelength that bisects the cumulative line flux) increases with blueshift. In contrast, the C IV line center shows weaker variability at the extreme blueshifts. Quasars with the high-blueshift C IV lines tend to have less variable continuum emission, when controlling for EW, luminosity, and redshift. Our results support the scenario that high-blueshift sources tend to have large Eddington ratios.

Impact on mortality of prompt admission to critical care for deteriorating ward patients: an instrumental variable analysis using critical care bed strain.

PubMed

Harris, Steve; Singer, Mervyn; Sanderson, Colin; Grieve, Richard; Harrison, David; Rowan, Kathryn

2018-05-07

To estimate the effect of prompt admission to critical care on mortality for deteriorating ward patients. We performed a prospective cohort study of consecutive ward patients assessed for critical care. Prompt admissions (within 4 h of assessment) were compared to a 'watchful waiting' cohort. We used critical care strain (bed occupancy) as a natural randomisation event that would predict prompt transfer to critical care. Strain was classified as low, medium or high (2+, 1 or 0 empty beds). This instrumental variable (IV) analysis was repeated for the subgroup of referrals with a recommendation for critical care once assessed. Risk-adjusted 90-day survival models were also constructed. A total of 12,380 patients from 48 hospitals were available for analysis. There were 2411 (19%) prompt admissions (median delay 1 h, IQR 1-2) and 9969 (81%) controls; 1990 (20%) controls were admitted later (median delay 11 h, IQR 6-26). Prompt admissions were less frequent (p < 0.0001) as strain increased from low (22%), to medium (15%) to high (9%); the median delay to admission was 3, 4 and 5 h respectively. In the IV analysis, prompt admission reduced 90-day mortality by 7.4% (95% CI 1.7-18.5%, p = 0.117) overall, and 16.2% (95% CI 1.1-31.3%, p = 0.036) for those recommended for critical care. In the risk-adjust survival model, 90-day mortality was similar. After allowing for unobserved prognostic differences between the groups, we find that prompt admission to critical care leads to lower 90-day mortality for patients assessed and recommended to critical care.

The impact of health insurance programs on out-of-pocket expenditures in Indonesia: an increase or a decrease?

PubMed

Aji, Budi; De Allegri, Manuela; Souares, Aurelia; Sauerborn, Rainer

2013-07-18

We used panel data from the Indonesian Family Life Survey to investigate the impact of health insurance programs on reducing out-of-pocket expenditures. We employed three linear panel data models, two of which accounted for endogeneity: pooled ordinary least squares (OLS), pooled two-stage least squares (2SLS) for instrumental variable (IV), and fixed effects (FE). The study revealed that two health insurance programs had a significantly negative impact on out-of-pocket expenditures by using IV estimates. In the IV model, Askeskin decreased out-of-pocket expenditures by 34% and Askes by 55% compared with non-Askeskin and non-Askes, respectively, while Jamsostek was found to bear a nonsignificant effect on out-of-pocket expenditures. In the FE model, only Askeskin had a significant negative effect with an 11% reduction on out-of-pocket expenditures. This study showed that two large existing health insurance programs in Indonesia, Askeskin and Askes, effectively reduced household out-of-pocket expenditures. The ability of programs to offer financial protection by reducing out-of-pocket expenditures is likely to be a direct function of their benefits package and co-payment policies.

The Impact of Health Insurance Programs on Out-of-Pocket Expenditures in Indonesia: An Increase or a Decrease?

PubMed Central

Aji, Budi; De Allegri, Manuela; Souares, Aurelia; Sauerborn, Rainer

2013-01-01

We used panel data from the Indonesian Family Life Survey to investigate the impact of health insurance programs on reducing out-of-pocket expenditures. We employed three linear panel data models, two of which accounted for endogeneity: pooled ordinary least squares (OLS), pooled two-stage least squares (2SLS) for instrumental variable (IV), and fixed effects (FE). The study revealed that two health insurance programs had a significantly negative impact on out-of-pocket expenditures by using IV estimates. In the IV model, Askeskin decreased out-of-pocket expenditures by 34% and Askes by 55% compared with non-Askeskin and non-Askes, respectively, while Jamsostek was found to bear a nonsignificant effect on out-of-pocket expenditures. In the FE model, only Askeskin had a significant negative effect with an 11% reduction on out-of-pocket expenditures. This study showed that two large existing health insurance programs in Indonesia, Askeskin and Askes, effectively reduced household out-of-pocket expenditures. The ability of programs to offer financial protection by reducing out-of-pocket expenditures is likely to be a direct function of their benefits package and co-payment policies. PMID:23873263

45 CFR 310.25 - What conditions apply to acquisitions of Computerized Tribal IV-D Systems?

Code of Federal Regulations, 2010 CFR

2010-10-01

... FAMILIES, DEPARTMENT OF HEALTH AND HUMAN SERVICES COMPUTERIZED TRIBAL IV-D SYSTEMS AND OFFICE AUTOMATION... Acquisition Threshold; (c) Software and ownership rights. (1) All procurement and contract instruments must... Computerized Tribal IV-D System software or enhancements thereof and all associated documentation designed...

40 CFR Appendix IV to Part 261 - Reserved

Code of Federal Regulations, 2010 CFR

2010-07-01

... AND LISTING OF HAZARDOUS WASTE Financial Requirements for Management of Excluded Hazardous Secondary Materials Wording of the instruments. Appendix IV to Part 261 [Reserved for Radioactive Waste Test Methods] ...

Child height, health and human capital: Evidence using genetic markers

PubMed Central

von Hinke Kessler Scholder, Stephanie; Davey Smith, George; Lawlor, Debbie A.; Propper, Carol; Windmeijer, Frank

2013-01-01

Height has long been recognized as being associated with better outcomes: the question is whether this association is causal. We use children's genetic variants as instrumental variables to deal with possible unobserved confounders and examine the effect of child/adolescent height on a wide range of outcomes: academic performance, IQ, self-esteem, depression symptoms and behavioral problems. OLS findings show that taller children have higher IQ, perform better in school, and are less likely to have behavioral problems. The IV results differ: taller girls (but not boys) have better cognitive performance and, in contrast to the OLS, greater height appears to increase behavioral problems. PMID:25673883

Child height, health and human capital: Evidence using genetic markers.

PubMed

von Hinke Kessler Scholder, Stephanie; Davey Smith, George; Lawlor, Debbie A; Propper, Carol; Windmeijer, Frank

2013-01-01

Height has long been recognized as being associated with better outcomes: the question is whether this association is causal. We use children's genetic variants as instrumental variables to deal with possible unobserved confounders and examine the effect of child/adolescent height on a wide range of outcomes: academic performance, IQ, self-esteem, depression symptoms and behavioral problems. OLS findings show that taller children have higher IQ, perform better in school, and are less likely to have behavioral problems. The IV results differ: taller girls (but not boys) have better cognitive performance and, in contrast to the OLS, greater height appears to increase behavioral problems.

Media Influences on Social Outcomes: The Impact of MTV’s 16 and Pregnant on Teen Childbearing.

PubMed

Kearney, Melissa S; Levine, Phillip B

2015-12-01

This paper explores the impact of the introduction of the widely viewed MTV reality show 16 and Pregnant on teen childbearing. Our main analysis relates geographic variation in changes in teen childbearing rates to viewership of the show. We implement an instrumental variables (IV ) strategy using local area MTV ratings data from a pre-period to predict local area 16 and Pregnant ratings. The results imply that this show led to a 4.3 percent reduction in teen births. An examination of Google Trends and Twitter data suggest that the show led to increased interest in contraceptive use and abortion.

Insurance Disruption due to Spousal Medicare Transitions: Implications for Access to Care and Health Care Utilization for Women Approaching Age 65

PubMed Central

Schumacher, Jessica R; Smith, Maureen A; Liou, Jinn-Ing; Pandhi, Nancy

2009-01-01

Objective To assess whether a husband's Medicare transition leads to insurance disruptions for his wife that impact her perceived access to care, health care utilization, or health status. Data Sources/Study Setting Respondents were married women under age 65 from the 2003–2005 round of the Wisconsin Longitudinal Study (N=655). Study Design Instrumental variable (IV) linear and IV-probit analyses provided unbiased estimates of the effect of an insurance disruption on study outcomes. The instrument was the husband's age: (1) women with husbands who transitioned to Medicare within the previous year (age 65–66); (2) women with husbands who did not transition (60

Evaluation of the efficacy of rotary vs. hand files in root canal preparation of primary teeth in vitro using CBCT.

PubMed

Musale, P K; Mujawar, S A V

2014-04-01

This in vitro study aimed to evaluate the efficacy of rotary ProFile, ProTaper, Hero Shaper and K-files in shaping ability, cleaning efficacy, preparation time and instrument distortion in primary molars. Sixty extracted primary mandibular second molars were divided into four equal groups: Group I K-file, Group II ProFile, Group III ProTaper file and Group IV Hero Shaper file. The shaping ability was determined by comparing pre- and post-instrumentation CBCT scans and data analysed with SPSS program using the Chi-square test. Cleaning efficacy was evaluated by the degree of India ink removal from the canal walls under stereomicroscopy. Instrumentation times were calculated for each tooth and instrument distortion was visually checked and duly noted. The cleaning efficacy and instrumentation time were determined using ANOVA with Tukey's correction. Instrument distortion was analysed using Chi-square test. The canal taper was significantly more conical for rotary files as compared to K-files with Chi-square test (p < 0.05). Cleaning efficacy of rotary files with average scores (Groups II- 0.68, III- 0.48 and IV- 0.58) was significantly better than K-files (Group I- 0.93) (p < 0.05). Mean instrumentation time with K-file (20.7 min) was significantly higher than rotary files (Groups II 8.9, III 5.6, and IV 8.1 min) (p < 0.05). Instrument distortion was observed in Group I (4.3%), while none of the rotary files were distorted. Rotary files prepared more conical canals in primary teeth than manual instruments. Reduced preparation time with rotary files enhances patient cooperation especially in young children.

Demonstration of the MPV at Former Waikoloa Maneuver Area in Hawaii: UXO Characterization in Challenging Survey Environments Using the MPV

DTIC Science & Technology

2015-10-01

Hawaii HASP Health and Safety Plan IDA Institute for Defense Analyses IVS Instrument Verification Strip m Meter mm Millimeter MPV Man Portable...the ArcSecond laser ranger was impractical due to the requirement to maintain line-of-sight for three rovers and tedious calibration. The SERDP...within 0.1m spacing and 99% within 0.15 m Repeatability of Instrument Verification Strip (IVS) survey   Amplitude of EM anomaly Amplitude of

Using Instrumental Variable (IV) Tests to Evaluate Model Specification in Latent Variable Structural Equation Models*

PubMed Central

Kirby, James B.; Bollen, Kenneth A.

2009-01-01

Structural Equation Modeling with latent variables (SEM) is a powerful tool for social and behavioral scientists, combining many of the strengths of psychometrics and econometrics into a single framework. The most common estimator for SEM is the full-information maximum likelihood estimator (ML), but there is continuing interest in limited information estimators because of their distributional robustness and their greater resistance to structural specification errors. However, the literature discussing model fit for limited information estimators for latent variable models is sparse compared to that for full information estimators. We address this shortcoming by providing several specification tests based on the 2SLS estimator for latent variable structural equation models developed by Bollen (1996). We explain how these tests can be used to not only identify a misspecified model, but to help diagnose the source of misspecification within a model. We present and discuss results from a Monte Carlo experiment designed to evaluate the finite sample properties of these tests. Our findings suggest that the 2SLS tests successfully identify most misspecified models, even those with modest misspecification, and that they provide researchers with information that can help diagnose the source of misspecification. PMID:20419054

A Multivariate Twin Study of the DSM-IV Criteria for Antisocial Personality Disorder

PubMed Central

Kendler, Kenneth S.; Aggen, Steven H.; Patrick, Christopher J.

2012-01-01

BACKGROUND Many assessment instruments for psychopathy are multidimensional, suggesting that distinguishable factors are needed to effectively capture variation in this personality domain. However, no prior study has examined the factor structure of the DSM-IV criteria for antisocial personality disorder (ASPD). METHODS Self-report questionnaire items reflecting all A criteria for DSM-IV ASPD were available from 4,291 twins (including both members of 1,647 pairs) from the Virginia Adult Study of Psychiatric and Substance Use Disorders. Exploratory factor analysis and twin model fitting were performed using, respectively, Mplus and Mx. RESULTS Phenotypic factor analysis produced evidence for 2 correlated factors: aggressive-disregard and disinhibition. The best-fitting multivariate twin model included two genetic and one unique environmental common factor, along with criteria-specific genetic and environmental effects. The two genetic factors closely resembled the phenotypic factors and varied in their prediction of a range of relevant criterion variables. Scores on the genetic aggressive-disregard factor score were more strongly associated with risk for conduct disorder, early and heavy alcohol use, and low educational status, whereas scores on the genetic disinhibition factor score were more strongly associated with younger age, novelty seeking, and major depression. CONCLUSION From a genetic perspective, the DSM-IV criteria for ASPD do not reflect a single dimension of liability but rather are influenced by two dimensions of genetic risk reflecting aggressive-disregard and disinhibition. The phenotypic structure of the ASPD criteria results largely from genetic and not from environmental influences. PMID:21762879

Cerebral and brainstem electrophysiologic activity during euthanasia with pentobarbital sodium in horses.

PubMed

Aleman, M; Williams, D C; Guedes, A; Madigan, J E

2015-01-01

An overdose of pentobarbital sodium administered i.v. is the most commonly used method of euthanasia in veterinary medicine. Determining death after the infusion relies on the observation of physical variables. However, it is unknown when cortical electrical activity and brainstem function are lost in a sequence of events before death. To examine changes in the electrical activity of the cerebral cortex and brainstem during an overdose of pentobarbital sodium solution for euthanasia. Our testing hypothesis is that isoelectric pattern of the brain in support of brain death occurs before absence of electrocardiogram (ECG) activity. Fifteen horses requiring euthanasia. Prospective observational study. Horses with neurologic, orthopedic, and cardiac illnesses were selected and instrumented for recording of electroencephalogram, electrooculogram, brainstem auditory evoked response (BAER), and ECG. Physical and neurologic (brainstem reflexes) variables were monitored. Loss of cortical electrical activity occurred during or within 52 seconds after the infusion of euthanasia solution. Cessation of brainstem function as evidenced by a lack of brainstem reflexes and disappearance of the BAER happened subsequently. Despite undetectable heart sounds, palpable arterial pulse, and mean arterial pressure, recordable ECG was the last variable to be lost after the infusion (5.5-16 minutes after end of the infusion). Overdose of pentobarbital sodium solution administered i.v. is an effective, fast, and humane method of euthanasia. Brain death occurs within 73-261 seconds of the infusion. Although absence of ECG activity takes longer to occur, brain death has already occurred. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

Expectations among the elderly about nursing home entry.

PubMed

Lindrooth, R C; Hoerger, T J; Norton, E C

2000-12-01

To assess whether the covariates that explain expectations of nursing home entry are consistent with the characteristics of those who enter nursing homes. Waves 1 and 2 of the Assets and Health Dynamics Among the Oldest Old (AHEAD) survey. We model expectations about nursing home entry as a function of expectations about leaving a bequest, living at least ten years, health condition, and other observed characteristics. We use an instrumental variables and generalized least squares (IV-GLS) method based on Hausman and Taylor (1981) to obtain more efficient estimates than fixed effects, without the restrictive assumptions of random effects. Expectations about nursing home entry are reasonably close to the actual probability of nursing home entry. Most of the variables that affect actual entry also have significant effects on expectations about entry. Medicaid subsidies for nursing home care may have little effect on expectations about nursing home entry; individuals in the lowest asset quartile, who are most likely to receive these subsidies, report probabilities not significantly different from those in other quartiles. Application of the IV-GLS approach is supported by a series of specification tests. We find that expectations about future nursing home entry are consistent with the characteristics of actual entrants. Underestimation of risk of nursing home entry as a reason for low levels of long-term care insurance is not supported by this analysis.

Expectations among the elderly about nursing home entry.

PubMed Central

Lindrooth, R C; Hoerger, T J; Norton, E C

2000-01-01

OBJECTIVE: To assess whether the covariates that explain expectations of nursing home entry are consistent with the characteristics of those who enter nursing homes. DATA SOURCES: Waves 1 and 2 of the Assets and Health Dynamics Among the Oldest Old (AHEAD) survey. STUDY DESIGN: We model expectations about nursing home entry as a function of expectations about leaving a bequest, living at least ten years, health condition, and other observed characteristics. We use an instrumental variables and generalized least squares (IV-GLS) method based on Hausman and Taylor (1981) to obtain more efficient estimates than fixed effects, without the restrictive assumptions of random effects. PRINCIPAL FINDINGS: Expectations about nursing home entry are reasonably close to the actual probability of nursing home entry. Most of the variables that affect actual entry also have significant effects on expectations about entry. Medicaid subsidies for nursing home care may have little effect on expectations about nursing home entry; individuals in the lowest asset quartile, who are most likely to receive these subsidies, report probabilities not significantly different from those in other quartiles. Application of the IV-GLS approach is supported by a series of specification tests. CONCLUSIONS: We find that expectations about future nursing home entry are consistent with the characteristics of actual entrants. Underestimation of risk of nursing home entry as a reason for low levels of long-term care insurance is not supported by this analysis. PMID:11130816

Heterogeneity in Positive Predictive Value of RAS Mutations in Cytologically Indeterminate Thyroid Nodules.

PubMed

Nabhan, Fadi; Porter, Kyle; Lupo, Mark A; Randolph, Gregory W; Patel, Kepal N; Kloos, Richard T

2018-06-01

RAS mutations are common in the available mutational analysis of cytologically indeterminate (Cyto-I) thyroid nodules. However, their reported positive predictive value (PPV) for cancer is widely variable. The reason for this variability is unknown, and it causes clinical management uncertainty. A systematic review was performed, evaluating the PPV for cancer in RAS mutation positive Cyto-I nodules, and variables that might affect residual heterogeneity across the different studies were considered. PubMed was searched through February 22, 2017, including studies that evaluated at least one type of RAS mutation in Cyto-I nodules, including any (or all) of the Bethesda III/IV/V categories or their equivalents and where the histological diagnosis was available. The PPV residual heterogeneity was investigated after accounting for Bethesda classification, blindedness of the histopathologist to the RAS mutational status, Bethesda category-specific cancer prevalence for each study, and which RAS genes and codons were tested. This was studied using five meta-regression models fit to different sets of Bethesda classification categories: Bethesda III, IV, or V (III/IV/V); Bethesda III or IV (III/IV); Bethesda III only; Bethesda IV only; and Bethesda V only. Of 1831 studies, 23 were eligible for data inclusion. Wide ranges of PPV were found at 0-100%, 28-100%, and 0-100% in Bethesda III, IV, and V, respectively. Residual heterogeneity remained moderately high for PPV after accounting for the above moderators for Bethesda III/IV/V (21 studies; I 2  = 59.5%) and Bethesda III/IV (19 studies; I 2  = 66.0%), with significant Cochran's Q-test for residual heterogeneity (p < 0.001). Among individual Bethesda categories, residual heterogeneity was: Bethesda III (eight studies; I 2  = 89.0%), IV (12 studies; I 2  = 53.5%), and V (10 studies; I 2  = 34.4%), with significant Cochran's Q-test for Bethesda III (p < 0.001) and IV (p = 0.04). The PPV of RAS mutations in Bethesda III and IV categories is quite heterogeneous across different studies, creating low confidence in the accuracy of a single estimate of PPV. Clinicians must appreciate this wide variability when managing a RAS-mutated Cyto-I nodule. Future studies should seek to resolve this unexplained variability.

The Correlated Variations of {\\rm{C}}\\,{\\rm{IV}} Narrow Absorption Lines and Quasar Continuum

NASA Astrophysics Data System (ADS)

Chen, Zhi-Fu; Pang, Ting-Ting; He, Bing; Huang, Yong

2018-06-01

We assemble 207 variable quasars from the Sloan Digital Sky Survey, all with at least 3 observations, to analyze C IV narrow absorption doublets, and obtain 328 C IV narrow absorption line systems. We find that 19 out of 328 C IV narrow absorption line systems were changed by | {{Δ }}{W}rλ 1548| ≥slant 3{σ }{{Δ }{W}rλ 1548} on timescales from 15.9 to 1477 days at rest-frame. Among the 19 obviously variable C IV systems, we find that (1) 14 systems have relative velocities {\\upsilon }r> 0.01c and 4 systems have {\\upsilon }r> 0.1c, where c is the speed of light; (2) 13 systems are accompanied by other variable C IV systems; (3) 9 systems were changed continuously during multiple observations; and (4) 1 system with {\\upsilon }r = 16,862 km s‑1 was enhanced by {{Δ }}{W}rλ 1548=2.7{σ }{{Δ }{W}rλ 1548} in 0.67 day at rest-frame. The variations of absorption lines are inversely correlated with the changes in the ionizing continuum. We also find that large variations of C IV narrow absorption lines are form differently over a short timescale.

A comparative evaluation of cleaning efficacy (debris and smear layer removal) of hand and two NiTi rotary instrumentation systems (K3 and ProTaper): a SEM study.

PubMed

Reddy, K Balakoti; Dash, Shreemoy; Kallepalli, Sowmya; Vallikanthan, Sangeetha; Chakrapani, N; Kalepu, Vamsi

2013-11-01

The present study was conducted to compare the cleaning efficacy (debris and smear layer removal) of hand and two NiTi rotary instrumentation systems (K3 and ProTaper). Sixty single rooted human maxillary anterior teeth decoronated at the cementoenamel junction were used. All the specimens were divided into four groups of 15 teeth each, group I--ProTaper rotary instrumentation done, group II--K3 rotary instrumentation done, group III--Stainless steel K-file instrumentation done, group IV--root canal irrigation without instrumentation. Root canal preparation was done in a crown down manner and 3% sodium hypochlorite was used as irrigant after each file followed by final rinse with 5 ml of 17% EDTA solution, then specimens were scanning electron microscopic (SEM) examination. Statistical analysis was done using one-way ANOVA followed by post hoc Tukey's HSD test. Group I showed highly statistical significant difference compared to other groups. There was no statistically significant difference considering smear layer at any levels among the groups with no smear layer formation in group IV. ProTaper rotary instrumentation showed the maximum cleaning efficacy followed by K3 rotary instrumentation in the coronal, middle and apical thirds of the root canal. ProTaper rotary instruments are more efficient than hand and K3 rotary instruments during root canal treatment.

Planning for an Evaluation of Teaching Performance. Volume IV. Summaries of Instruments for Use in Evaluating Teacher Performance.

ERIC Educational Resources Information Center

Yuzdepski, I., Comp.; Elliott, L., Comp.

This document presents information, in the form of summary sheets, on 54 teacher evaluation instruments. Each summary contains pertinent information about the instrument regarding publishing company, author, criteria evaluated, subject of observation, category dimension, and coding units. The 19 criteria used in the evaluation tests, which were…

High speed photography, videography, and photonics IV; Proceedings of the Meeting, San Diego, CA, Aug. 19, 20, 1986

NASA Technical Reports Server (NTRS)

Ponseggi, B. G. (Editor)

1986-01-01

Various papers on high-speed photography, videography, and photonics are presented. The general topics addressed include: photooptical and video instrumentation, streak camera data acquisition systems, photooptical instrumentation in wind tunnels, applications of holography and interferometry in wind tunnel research programs, and data analysis for photooptical and video instrumentation.

Reduced interdecadal variability of Atlantic Meridional Overturning Circulation under global warming.

PubMed

Cheng, Jun; Liu, Zhengyu; Zhang, Shaoqing; Liu, Wei; Dong, Lina; Liu, Peng; Li, Hongli

2016-03-22

Interdecadal variability of the Atlantic Meridional Overturning Circulation (AMOC-IV) plays an important role in climate variation and has significant societal impacts. Past climate reconstruction indicates that AMOC-IV has likely undergone significant changes. Despite some previous studies, responses of AMOC-IV to global warming remain unclear, in particular regarding its amplitude and time scale. In this study, we analyze the responses of AMOC-IV under various scenarios of future global warming in multiple models and find that AMOC-IV becomes weaker and shorter with enhanced global warming. From the present climate condition to the strongest future warming scenario, on average, the major period of AMOC-IV is shortened from ∼50 y to ∼20 y, and the amplitude is reduced by ∼60%. These reductions in period and amplitude of AMOC-IV are suggested to be associated with increased oceanic stratification under global warming and, in turn, the speedup of oceanic baroclinic Rossby waves.

Adult height, coronary heart disease and stroke: a multi-locus Mendelian randomization meta-analysis

PubMed Central

Nüesch, Eveline; Dale, Caroline; Palmer, Tom M; White, Jon; Keating, Brendan J; van Iperen, Erik PA; Goel, Anuj; Padmanabhan, Sandosh; Asselbergs, Folkert W; Verschuren, WM; Wijmenga, C; Van der Schouw, YT; Onland-Moret, NC; Lange, Leslie A; Hovingh, GK; Sivapalaratnam, Suthesh; Morris, Richard W; Whincup, Peter H; Wannamethe, Goya S; Gaunt, Tom R; Ebrahim, Shah; Steel, Laura; Nair, Nikhil; Reiner, Alexander P; Kooperberg, Charles; Wilson, James F; Bolton, Jennifer L; McLachlan, Stela; Price, Jacqueline F; Strachan, Mark WJ; Robertson, Christine M; Kleber, Marcus E; Delgado, Graciela; März, Winfried; Melander, Olle; Dominiczak, Anna F; Farrall, Martin; Watkins, Hugh; Leusink, Maarten; Maitland-van der Zee, Anke H; de Groot, Mark CH; Dudbridge, Frank; Hingorani, Aroon; Ben-Shlomo, Yoav; Lawlor, Debbie A; Amuzu, A; Caufield, M; Cavadino, A; Cooper, J; Davies, TL; Drenos, F; Engmann, J; Finan, C; Giambartolomei, C; Hardy, R; Humphries, SE; Hypponen, E; Kivimaki, M; Kuh, D; Kumari, M; Ong, K; Plagnol, V; Power, C; Richards, M; Shah, S; Shah, T; Sofat, R; Talmud, PJ; Wareham, N; Warren, H; Whittaker, JC; Wong, A; Zabaneh, D; Davey Smith, George; Wells, Jonathan C; Leon, David A; Holmes, Michael V; Casas, Juan P

2016-01-01

Abstract Background: We investigated causal effect of completed growth, measured by adult height, on coronary heart disease (CHD), stroke and cardiovascular traits, using instrumental variable (IV) Mendelian randomization meta-analysis. Methods: We developed an allele score based on 69 single nucleotide polymorphisms (SNPs) associated with adult height, identified by the IBCCardioChip, and used it for IV analysis against cardiovascular risk factors and events in 21 studies and 60 028 participants. IV analysis on CHD was supplemented by summary data from 180 height-SNPs from the GIANT consortium and their corresponding CHD estimates derived from CARDIoGRAMplusC4D. Results: IV estimates from IBCCardioChip and GIANT-CARDIoGRAMplusC4D showed that a 6.5-cm increase in height reduced the odds of CHD by 10% [odds ratios 0.90; 95% confidence intervals (CIs): 0.78 to 1.03 and 0.85 to 0.95, respectively],which agrees with the estimate from the Emerging Risk Factors Collaboration (hazard ratio 0.93; 95% CI: 0.91 to 0.94). IV analysis revealed no association with stroke (odds ratio 0.97; 95% CI: 0.79 to 1.19). IV analysis showed that a 6.5-cm increase in height resulted in lower levels of body mass index (P < 0.001), triglycerides (P < 0.001), non high-density (non-HDL) cholesterol (P < 0.001), C-reactive protein (P = 0.042), and systolic blood pressure (P = 0.064) and higher levels of forced expiratory volume in 1 s and forced vital capacity (P < 0.001 for both). Conclusions: Taller individuals have a lower risk of CHD with potential explanations being that taller people have a better lung function and lower levels of body mass index, cholesterol and blood pressure. PMID:25979724

Tests of the Monte Carlo simulation of the photon-tagger focal-plane electronics at the MAX IV Laboratory

NASA Astrophysics Data System (ADS)

Preston, M. F.; Myers, L. S.; Annand, J. R. M.; Fissum, K. G.; Hansen, K.; Isaksson, L.; Jebali, R.; Lundin, M.

2014-04-01

Rate-dependent effects in the electronics used to instrument the tagger focal plane at the MAX IV Laboratory were recently investigated using the novel approach of Monte Carlo simulation to allow for normalization of high-rate experimental data acquired with single-hit time-to-digital converters (TDCs). The instrumentation of the tagger focal plane has now been expanded to include multi-hit TDCs. The agreement between results obtained from data taken using single-hit and multi-hit TDCs demonstrate a thorough understanding of the behavior of the detector system.

The Standardized Assessment of Personality-Abbreviated Scale as a screening instrument for personality disorders in substance-dependent criminal offenders.

PubMed

Jansen, Brigitte P M; Damen, Katinka F M; Hoffman, Tonko O; Vellema, Sietske L

2013-05-01

Personality disorders (PDs) are considered to be potential predictors of treatment outcome in substance-dependent patients and potential treatment matching variables. There is a need for a brief and simple screening instrument for PDs that can be used in routine psychological assessment, especially in a treatment setting for previously substance-dependent criminal offenders, where a high prevalence of PDs is expected. This study investigated the psychometric properties of the Standardized Assessment of Personality-Abbreviated Scale (SAPAS), a commonly used screening interview for PDs, in a population of inpatient criminal offenders with a history of substance dependence. Various statistical procedures were used to establish reliability and validity measures, such as Kuder-Richardson 20, confirmative factor analysis, receiver operating characteristic analysis and multitrait multimethod matrix. The SAPAS was administered to 101 inpatient criminal offenders with a history of substance dependence at baseline. Within three weeks, participants were administered the Structured Interview for DSM-IV Personality in order to assess the presence of PDs. Results show limited evidence to make firm conclusions on the psychometric qualities of the SAPAS as a screening instrument for comorbid PDs in a substance dependence treatment setting for criminal offenders. Suggestions for improvement concerning the psychometric qualities of the SAPAS as a screening instrument for this population are noted. Copyright © 2012 John Wiley & Sons, Ltd.

The Concise Knowledge Astronomy

NASA Astrophysics Data System (ADS)

Clerke, Agnes Mary; Fowler, Alfred; Ellard Gore, John

2011-01-01

Preface; Section I. History Agnes M. Clerke: 1. From Hipparchus to Laplace; 2. A century of progress; Section II. Geometrical Astronomy and Astronomical Instruments A. Fowler: 1. The Earth and its rotation; 2. The Earth's revolution round the Sun; 3. How the positions of the heavenly bodies are defined; 4. The Earth's orbit; 5. Mean solar time; 6. The movements of the Moon; 7. Movements of planets, satellites, and comets; 8. Eclipses and occultations; 9. How to find our situation on the Earth; 10. The exact size and shape of the earth; 11. The distances and dimensions of the heavenly bodies; 12. The masses of celestial bodies; 13. Gravitational effects of Sun and moon upon the Earth; 14. Instrumental measurement of angles and time; 15. Telescopes; 16. Instruments of precision; 17. Astrophysical instruments; Section III. The Solar System Agnes M. Clerke: 1. The solar system as a whole; 2. The Sun; 3. The Sun's surroundings; 4. The interior planets; 5. The Earth and Moon; 6. The planet Mars; 7. The asteroids; 8. The planet Jupiter; 9. The Saturnian system; 10. Uranus and Neptune; 11. Famous comets; 12. Nature and origin of comets; 13. Meteorites and shooting stars; Section IV. The Sidereal Heavens J.E. Gore: 1. The stars and constellations; 2. Double, multiple, and coloured stars; 3. The distances and motions of the stars; 4. Binary stars; 5. Variable and temporary stars; 6. Clusters and nebulae; 7. The construction of the heavens; Index.

The Hexapod Telescope -- A Never-ending Story

NASA Astrophysics Data System (ADS)

Chini, Rolf

The 1.5 m Hexapod Telescope is the prototype of a worldwide unique design concept for future telescopes. Its technical innovations comprise i) a mounting where the classical axes are replaced by six high-precision struts of variable lengths, ii) an actively controlled primary which consists of a thin Zerodur meniscus that is permanently fixed to a CFRP grid structure, iii) a secondary whose support legs are also designed as a Hexapod to compensate for gravitational deformation due to different elevations and, iv) a laser gyro system to provide the pointing. The telescope is currently tested in the Botanical Garden of the Ruhr-University Bochum and it is planned to transfer the instrument to Cerro Armazones, Chile after the world exhibition EXPO 2000.

A multivariate twin study of the DSM-IV criteria for antisocial personality disorder.

PubMed

Kendler, Kenneth S; Aggen, Steven H; Patrick, Christopher J

2012-02-01

Many assessment instruments for psychopathy are multidimensional, suggesting that distinguishable factors are needed to effectively capture variation in this personality domain. However, no prior study has examined the factor structure of the DSM-IV criteria for antisocial personality disorder (ASPD). Self-report questionnaire items reflecting all A criteria for DSM-IV ASPD were available from 4291 twins (including both members of 1647 pairs) from the Virginia Adult Study of Psychiatric and Substance Use Disorders. Exploratory factor analysis and twin model fitting were performed using, respectively, Mplus and Mx. Phenotypic factor analysis produced evidence for two correlated factors: aggressive-disregard and disinhibition. The best-fitting multivariate twin model included two genetic and one unique environmental common factor, along with criteria-specific genetic and environmental effects. The two genetic factors closely resembled the phenotypic factors and varied in their prediction of a range of relevant criterion variables. Scores on the genetic aggressive-disregard factor score were more strongly associated with risk for conduct disorder, early and heavy alcohol use, and low educational status, whereas scores on the genetic disinhibition factor score were more strongly associated with younger age, novelty seeking, and major depression. From a genetic perspective, the DSM-IV criteria for ASPD do not reflect a single dimension of liability but rather are influenced by two dimensions of genetic risk reflecting aggressive-disregard and disinhibition. The phenotypic structure of the ASPD criteria results largely from genetic and not from environmental influences. Copyright © 2012 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

Variable rainfall intensity and tillage effects on runoff, sediment, and carbon losses from a loamy sand under simulated rainfall.

PubMed

Truman, C C; Strickland, T C; Potter, T L; Franklin, D H; Bosch, D D; Bednarz, C W

2007-01-01

The low-carbon, intensively cropped Coastal Plain soils of Georgia are susceptible to runoff, soil loss, and drought. Reduced tillage systems offer the best management tool for sustained row crop production. Understanding runoff, sediment, and chemical losses from conventional and reduced tillage systems is expected to improve if the effect of a variable rainfall intensity storm was quantified. Our objective was to quantify and compare effects of a constant (Ic) intensity pattern and a more realistic, observed, variable (Iv) rainfall intensity pattern on runoff (R), sediment (E), and carbon losses (C) from a Tifton loamy sand cropped to conventional-till (CT) and strip-till (ST) cotton (Gossypium hirsutum L.). Four treatments were evaluated: CT-Ic, CT-Iv, ST-Ic, and ST-Iv, each replicated three times. Field plots (n=12), each 2 by 3 m, were established on each treatment. Each 6-m2 field plot received simulated rainfall at a constant (57 mm h(-1)) or variable rainfall intensity pattern for 70 min (12-run ave.=1402 mL; CV=3%). The Iv pattern represented the most frequent occurring intensity pattern for spring storms in the region. Compared with CT, ST decreased R by 2.5-fold, E by 3.5-fold, and C by 7-fold. Maximum runoff values for Iv events were 1.6-fold higher than those for Ic events and occurred 38 min earlier. Values for Etot and Ctot for Iv events were 19-36% and 1.5-fold higher than corresponding values for Ic events. Values for Emax and Cmax for Iv events were 3-fold and 4-fold higher than corresponding values for Ic events. Carbon enrichment ratios (CER) were or=1.0 for CT plots (except for first 20 min). Maximum CER for CT-Ic, CT-Iv, ST-Ic, and ST-Iv were 2.0, 2.2, 1.0, and 1.2, respectively. Transport of sediment, carbon, and agrichemicals would be better understood if variable rainfall intensity patterns derived from natural rainfall were used in rainfall simulations to evaluate their fate and transport from CT and ST systems.

Revision to Planetary Protection Policy for Mars Missions

NASA Technical Reports Server (NTRS)

DeVincenzi, D. L.; Stabekis, P.; Barengoltz, J.; Morrison, David (Technical Monitor)

1994-01-01

Under existing COSPAR policy adopted in 1984, missions to Mars (landers, probes, and some orbiters) are designated as Category IV missions. As such, the procedures for implementing planetary protection requirements could include trajectory biasing, cleanrooms, bioload reduction, sterilization of hardware, and bioshields, i. e. requirements could be similar to Viking. However, in 1992, a U. S. National Academy of Sciences study recommended that controls on forward contamination of Mars be tied to specific mission objectives. The report recommended that Mars landers with life detection instruments be subject to at least Viking-level sterilization procedures for bioload reduction, while spacecraft (including orbiters) without life detection instruments be subject to at least Viking-level pre sterilization procedures for bioload reduction but need not be sterilized. In light of this, it is proposed that the current policy's Category IV missions and their planetary protection requirements be divided into two subcategories as follows: Category IV A, for missions comprising landers and probes without life detection experiments and some orbiters, which will meet a specified bioburden limit for exposed surfaces; Category IV B, for landers and probes with life detection experiments, which will require complete system sterilization. For Category IV A missions, bioburden specifications will be proposed and implementing procedures discussed. A resolution will be proposed to modify the existing COSPAR policy to reflect these changes. Similar specifications, procedures, and resolution for Category IV B missions will be the subject of a later study.

Variability in Wechsler Adult Intelligence Scale-IV subtest performance across age.

PubMed

Wisdom, Nick M; Mignogna, Joseph; Collins, Robert L

2012-06-01

Normal Wechsler Adult Intelligence Scale (WAIS)-IV performance relative to average normative scores alone can be an oversimplification as this fails to recognize disparate subtest heterogeneity that occurs with increasing age. The purpose of the present study is to characterize the patterns of raw score change and associated variability on WAIS-IV subtests across age groupings. Raw WAIS-IV subtest means and standard deviations for each age group were tabulated from the WAIS-IV normative manual along with the coefficient of variation (CV), a measure of score dispersion calculated by dividing the standard deviation by the mean and multiplying by 100. The CV further informs the magnitude of variability represented by each standard deviation. Raw mean scores predictably decreased across age groups. Increased variability was noted in Perceptual Reasoning and Processing Speed Index subtests, as Block Design, Matrix Reasoning, Picture Completion, Symbol Search, and Coding had CV percentage increases ranging from 56% to 98%. In contrast, Working Memory and Verbal Comprehension subtests were more homogeneous with Digit Span, Comprehension, Information, and Similarities percentage of the mean increases ranging from 32% to 43%. Little change in the CV was noted on Cancellation, Arithmetic, Letter/Number Sequencing, Figure Weights, Visual Puzzles, and Vocabulary subtests (<14%). A thorough understanding of age-related subtest variability will help to identify test limitations as well as further our understanding of cognitive domains which remain relatively steady versus those which steadily decline.

Toward a clearer portrayal of confounding bias in instrumental variable applications.

PubMed

Jackson, John W; Swanson, Sonja A

2015-07-01

Recommendations for reporting instrumental variable analyses often include presenting the balance of covariates across levels of the proposed instrument and levels of the treatment. However, such presentation can be misleading as relatively small imbalances among covariates across levels of the instrument can result in greater bias because of bias amplification. We introduce bias plots and bias component plots as alternative tools for understanding biases in instrumental variable analyses. Using previously published data on proposed preference-based, geography-based, and distance-based instruments, we demonstrate why presenting covariate balance alone can be problematic, and how bias component plots can provide more accurate context for bias from omitting a covariate from an instrumental variable versus non-instrumental variable analysis. These plots can also provide relevant comparisons of different proposed instruments considered in the same data. Adaptable code is provided for creating the plots.

Reduced interdecadal variability of Atlantic Meridional Overturning Circulation under global warming

PubMed Central

Cheng, Jun; Liu, Zhengyu; Zhang, Shaoqing; Liu, Wei; Dong, Lina; Liu, Peng; Li, Hongli

2016-01-01

Interdecadal variability of the Atlantic Meridional Overturning Circulation (AMOC-IV) plays an important role in climate variation and has significant societal impacts. Past climate reconstruction indicates that AMOC-IV has likely undergone significant changes. Despite some previous studies, responses of AMOC-IV to global warming remain unclear, in particular regarding its amplitude and time scale. In this study, we analyze the responses of AMOC-IV under various scenarios of future global warming in multiple models and find that AMOC-IV becomes weaker and shorter with enhanced global warming. From the present climate condition to the strongest future warming scenario, on average, the major period of AMOC-IV is shortened from ∼50 y to ∼20 y, and the amplitude is reduced by ∼60%. These reductions in period and amplitude of AMOC-IV are suggested to be associated with increased oceanic stratification under global warming and, in turn, the speedup of oceanic baroclinic Rossby waves. PMID:26951654

Predictors of comorbid personality disorders in patients with panic disorder with agoraphobia.

PubMed

Latas, M; Starcevic, V; Trajkovic, G; Bogojevic, G

2000-01-01

The aim of this study was to ascertain predictors of comorbid personality disorders in patients with panic disorder with agoraphobia (PDAG). Sixty consecutive outpatients with PDAG were administered the Structured Clinical Interview for DSM-IV Axis II Personality Disorders (SCID-II) for the purpose of diagnosing personality disorders. Logistic regressions were used to identify predictors of any comorbid personality disorder, any DSM-IV cluster A, cluster B, and cluster C personality disorder. Independent variables in these regressions were gender, age, duration of panic disorder (PD), severity of PDAG, and scores on self-report instruments that assess the patient's perception of their parents, childhood separation anxiety, and traumatic experiences. High levels of parental protection on the Parental Bonding Instrument (PBI), indicating a perception of the parents as overprotective and controlling, emerged as the only statistically significant predictor of any comorbid personality disorder. This finding was attributed to the association between parental overprotection and cluster B personality disorders, particularly borderline personality disorder. The duration of PD was a significant predictor of any cluster B and any cluster C personality disorder, suggesting that some of the cluster B and cluster C personality disorders may be a consequence of the long-lasting PDAG. Any cluster B personality disorder was also associated with younger age. In conclusion, despite a generally nonspecific nature of the relationship between parental overprotection in childhood and adult psychopathology, the findings of this study suggest some specificity for the association between parental overprotection in childhood and personality disturbance in PDAG patients, particularly cluster B personality disorders.

Actinide Corroles: Synthesis and Characterization of Thorium(IV) and Uranium(IV) bis(-chloride) Dimers

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

Ward, Ashleigh L.; Buckley, Heather L.; Gryko, Daniel T.

2013-12-01

The first synthesis and structural characterization of actinide corroles is presented. Thorium(IV) and uranium(IV) macrocycles of Mes2(p-OMePh)corrole were synthesised and characterized by single-crystal X-ray diffraction, UV-Visible spectroscopy, variable-temperature 1H NMR, ESI mass spectrometry and cyclic voltammetry.

High-resolution observations in the western Mediterranean Sea: the REP14-MED experiment

NASA Astrophysics Data System (ADS)

Onken, Reiner; Fiekas, Heinz-Volker; Beguery, Laurent; Borrione, Ines; Funk, Andreas; Hemming, Michael; Hernandez-Lasheras, Jaime; Heywood, Karen J.; Kaiser, Jan; Knoll, Michaela; Mourre, Baptiste; Oddo, Paolo; Poulain, Pierre-Marie; Queste, Bastien Y.; Russo, Aniello; Shitashima, Kiminori; Siderius, Martin; Thorp Küsel, Elizabeth

2018-04-01

The observational part of the REP14-MED experiment was conducted in June 2014 in the Sardo-Balearic Basin west of Sardinia (western Mediterranean Sea). Two research vessels collected high-resolution oceanographic data by means of hydrographic casts, towed systems, and underway measurements. In addition, a vast amount of data was provided by a fleet of 11 ocean gliders, time series were available from moored instruments, and information on Lagrangian flow patterns was obtained from surface drifters and one profiling float. The spatial resolution of the observations encompasses a spectrum over 4 orders of magnitude from 𝒪(101 m) to 𝒪(105 m), and the time series from the moored instruments cover a spectral range of 5 orders from 𝒪(101 s) to 𝒪(106 s). The objective of this article is to provide an overview of the huge data set which has been utilised by various studies, focusing on (i) water masses and circulation, (ii) operational forecasting, (iii) data assimilation, (iv) variability of the ocean, and (v) new payloads for gliders.

Cleanliness in the Root Canal System: An Scanning Electron Microscopic Evaluation of Manual and Automated Instrumentation using 4% Sodium Hypochlorite and EDTA (Glyde File Prep)―An in vitro Study

PubMed Central

Meshram, GK

2010-01-01

ABSTRACT Aim : To assess the cleaning efficacy of manual and automated instrumentation using 4% sodium hypochlorite singly and in combination with Glyde file Prep as root canal irrigant. Methodology : The study utilized 40 extracted human permanent premolars with single, straight and fully formed root. The teeth were then divided into four groups of ten each, Group I and II were prepared by manual instruments with 4% sodium hypochlorite used as irrigant singly [Group I] or in combination with Glyde file prep. Group III and IV were prepared by automated instruments at 250 rpm with 4% sodium hypochlorite as irrigant singly [Group III] and in combination with glyde file prep [Group IV] automated instrumentation. After completion of the root canal preparation the canal, teeth were prepared for SEM examination. These photomicrographs were qualitatively evaluated using criteria. Overall cleanliness, presence or absence of the smear layer, presence or absence of the debris, patency of the opening of dentinal tubules. Results : When comparing the cleansing efficacy of manual and automated instrumentation using 4% sodium hypochlorite better cleansing was there with manual instrumentation. When comparing the cleansing efficacy of manual and automated instrumentation using combination regime cleansing is better with automated instrumentation. When comparing the cleansing efficacy of manual instrumentation using 4% sodium hypochlorite singly and in combination with EDTA, the combination regime led to better cleansing. When comparing the cleansing efficacy of automated instrumentation using 4% sodium hypochlorite singly and in combination regime lead to better cleansing. Conclusion : Neither of instrumentation technique, nor irrigating regimes were capable of providing a completely clean canal. Automated instrumentation with a combination of sodium hypochlorite & EDTA resulted the best cleansing efficacy. PMID:27616839

Physical fitness predicts technical-tactical and time-motion profile in simulated Judo and Brazilian Jiu-Jitsu matches.

PubMed

Coswig, Victor S; Gentil, Paulo; Bueno, João C A; Follmer, Bruno; Marques, Vitor A; Del Vecchio, Fabrício B

2018-01-01

Among combat sports, Judo and Brazilian Jiu-Jitsu (BJJ) present elevated physical fitness demands from the high-intensity intermittent efforts. However, information regarding how metabolic and neuromuscular physical fitness is associated with technical-tactical performance in Judo and BJJ fights is not available. This study aimed to relate indicators of physical fitness with combat performance variables in Judo and BJJ. The sample consisted of Judo ( n  = 16) and BJJ ( n  = 24) male athletes. At the first meeting, the physical tests were applied and, in the second, simulated fights were performed for later notational analysis. The main findings indicate: (i) high reproducibility of the proposed instrument and protocol used for notational analysis in a mobile device; (ii) differences in the technical-tactical and time-motion patterns between modalities; (iii) performance-related variables are different in Judo and BJJ; and (iv) regression models based on metabolic fitness variables may account for up to 53% of the variances in technical-tactical and/or time-motion variables in Judo and up to 31% in BJJ, whereas neuromuscular fitness models can reach values up to 44 and 73% of prediction in Judo and BJJ, respectively. When all components are combined, they can explain up to 90% of high intensity actions in Judo. In conclusion, performance prediction models in simulated combat indicate that anaerobic, aerobic and neuromuscular fitness variables contribute to explain time-motion variables associated with high intensity and technical-tactical variables in Judo and BJJ fights.

Falsification Testing of Instrumental Variables Methods for Comparative Effectiveness Research.

PubMed

Pizer, Steven D

2016-04-01

To demonstrate how falsification tests can be used to evaluate instrumental variables methods applicable to a wide variety of comparative effectiveness research questions. Brief conceptual review of instrumental variables and falsification testing principles and techniques accompanied by an empirical application. Sample STATA code related to the empirical application is provided in the Appendix. Comparative long-term risks of sulfonylureas and thiazolidinediones for management of type 2 diabetes. Outcomes include mortality and hospitalization for an ambulatory care-sensitive condition. Prescribing pattern variations are used as instrumental variables. Falsification testing is an easily computed and powerful way to evaluate the validity of the key assumption underlying instrumental variables analysis. If falsification tests are used, instrumental variables techniques can help answer a multitude of important clinical questions. © Health Research and Educational Trust.

Use of Angiotensin-Converting Enzyme Inhibitors and Angiotensin Receptor Blockers for Geriatric Ischemic Stroke Patients: Are the Rates Right?

PubMed

Brooks, John M; Chapman, Cole G; Suneja, Manish; Schroeder, Mary C; Fravel, Michelle A; Schneider, Kathleen M; Wilwert, June; Li, Yi-Jhen; Chrischilles, Elizabeth A; Brenton, Douglas W; Brenton, Marian; Robinson, Jennifer

2018-05-30

Our objective is to estimate the effects associated with higher rates of renin-angiotensin system antagonists, angiotensin-converting enzyme inhibitors and angiotensin receptor blockers (ACEI/ARBs), in secondary prevention for geriatric (aged >65 years) patients with new ischemic strokes by chronic kidney disease (CKD) status. The effects of ACEI/ARBs on survival and renal risk were estimated by CKD status using an instrumental variable (IV) estimator. Instruments were based on local area variation in ACEI/ARB use. Data abstracted from charts were used to assess the assumptions underlying the instrumental estimator. ACEI/ARBs were used after stroke by 45.9% and 45.2% of CKD and non-CKD patients, respectively. ACEI/ARB rate differences across local areas grouped by practice styles were nearly identical for CKD and non-CKD patients. Higher ACEI/ARB use rates for non-CKD patients were associated with higher 2-year survival rates, whereas higher ACEI/ARB use rates for patients with CKD were associated with lower 2-year survival rates. While the negative survival estimates for patients with CKD were not statistically different from zero, they were statistically lower than the estimates for non-CKD patients. Confounders abstracted from charts were not associated with the instrumental variable used. Higher ACEI/ARB use rates had different survival implications for older ischemic stroke patients with and without CKD. ACEI/ARBs appear underused in ischemic stroke patients without CKD as higher use rates were associated with higher 2-year survival rates. This conclusion is not generalizable to the ischemic stroke patients with CKD, as higher ACEI/ARBS use rates were associated with lower 2-year survival rates that were statistically lower than the estimates for non-CKD patients. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Tutorial in Biostatistics: Instrumental Variable Methods for Causal Inference*

PubMed Central

Baiocchi, Michael; Cheng, Jing; Small, Dylan S.

2014-01-01

A goal of many health studies is to determine the causal effect of a treatment or intervention on health outcomes. Often, it is not ethically or practically possible to conduct a perfectly randomized experiment and instead an observational study must be used. A major challenge to the validity of observational studies is the possibility of unmeasured confounding (i.e., unmeasured ways in which the treatment and control groups differ before treatment administration which also affect the outcome). Instrumental variables analysis is a method for controlling for unmeasured confounding. This type of analysis requires the measurement of a valid instrumental variable, which is a variable that (i) is independent of the unmeasured confounding; (ii) affects the treatment; and (iii) affects the outcome only indirectly through its effect on the treatment. This tutorial discusses the types of causal effects that can be estimated by instrumental variables analysis; the assumptions needed for instrumental variables analysis to provide valid estimates of causal effects and sensitivity analysis for those assumptions; methods of estimation of causal effects using instrumental variables; and sources of instrumental variables in health studies. PMID:24599889

Factor Structure of the DSM-IV Criteria for College Students Using the Adult Behavior Checklist.

ERIC Educational Resources Information Center

Johnson, Brian D.; Smith, Everett V., Jr.

1998-01-01

The factor structure of the "Diagnostic and Statistical Manual of Mental Disorders" (DSM-IV) criteria for attention deficit hyperactivity disorder (ADHD) is evaluated in a sample of 1,503 college students. The Adult Behavior Checklist is evaluated as a screening instrument. Results support the extension of ADHD criteria for diagnosis to college…

49 CFR 572.137 - Test conditions and instrumentation.

Code of Federal Regulations, 2011 CFR

2011-10-01

...—Class 1000 (2) Neck: (i) Forces—Class 1000 (ii) Moments—Class 600 (iii) Pendulum acceleration—Class 180... and pendulum accelerations—Class 180 (iii) Sternum deflection—Class 600 (iv) Forces—Class 1000 (v...—Class 180 (6) Femur forces and knee pendulum—Class 600 (n) Coordinate signs for instrumentation polarity...

49 CFR 572.137 - Test conditions and instrumentation.

Code of Federal Regulations, 2010 CFR

2010-10-01

...—Class 1000 (2) Neck: (i) Forces—Class 1000 (ii) Moments—Class 600 (iii) Pendulum acceleration—Class 180... and pendulum accelerations—Class 180 (iii) Sternum deflection—Class 600 (iv) Forces—Class 1000 (v...—Class 180 (6) Femur forces and knee pendulum—Class 600 (n) Coordinate signs for instrumentation polarity...

49 CFR 572.137 - Test conditions and instrumentation.

Code of Federal Regulations, 2013 CFR

2013-10-01

...—Class 1000 (2) Neck: (i) Forces—Class 1000 (ii) Moments—Class 600 (iii) Pendulum acceleration—Class 180... and pendulum accelerations—Class 180 (iii) Sternum deflection—Class 600 (iv) Forces—Class 1000 (v...—Class 180 (6) Femur forces and knee pendulum—Class 600 (n) Coordinate signs for instrumentation polarity...

49 CFR 572.137 - Test conditions and instrumentation.

Code of Federal Regulations, 2014 CFR

2014-10-01

...—Class 1000 (2) Neck: (i) Forces—Class 1000 (ii) Moments—Class 600 (iii) Pendulum acceleration—Class 180... and pendulum accelerations—Class 180 (iii) Sternum deflection—Class 600 (iv) Forces—Class 1000 (v...—Class 180 (6) Femur forces and knee pendulum—Class 600 (n) Coordinate signs for instrumentation polarity...

49 CFR 572.137 - Test conditions and instrumentation.

Code of Federal Regulations, 2012 CFR

2012-10-01

...—Class 1000 (2) Neck: (i) Forces—Class 1000 (ii) Moments—Class 600 (iii) Pendulum acceleration—Class 180... and pendulum accelerations—Class 180 (iii) Sternum deflection—Class 600 (iv) Forces—Class 1000 (v...—Class 180 (6) Femur forces and knee pendulum—Class 600 (n) Coordinate signs for instrumentation polarity...

Evidence-Based Diagnosis: Incorporating Diagnostic Instruments into Clinical Practice

ERIC Educational Resources Information Center

Doss, Amanda Jensen

2005-01-01

This article is intended to serve as a practical guide for practitioners interested in incorporating evidence-based diagnosis (EBD) instruments into their clinical practices to refine the diagnostic process. Three measures are used to illustrate this process, the DISC-IV (Shaffer et al., 2000), the Schedule for Affective Disorders and…

[Instruments for quantitative methods of nursing research].

PubMed

Vellone, E

2000-01-01

Instruments for quantitative nursing research are a mean to objectify and measure a variable or a phenomenon in the scientific research. There are direct instruments to measure concrete variables and indirect instruments to measure abstract concepts (Burns, Grove, 1997). Indirect instruments measure the attributes by which a concept is made of. Furthermore, there are instruments for physiologic variables (e.g. for the weight), observational instruments (Check-lists e Rating Scales), interviews, questionnaires, diaries and the scales (Check-lists, Rating Scales, Likert Scales, Semantic Differential Scales e Visual Anologue Scales). The choice to select an instrument or another one depends on the research question and design. Instruments research are very useful in research both to describe the variables and to see statistical significant relationships. Very carefully should be their use in the clinical practice for diagnostic assessment.

Can we still learn something from the relationship between fertility and mother's employment? Evidence from developing countries.

PubMed

Cáceres-Delpiano, Julio

2012-02-01

In this work, I study the impact of fertility on mothers' employment for a sample of developing countries. Using the event of multiple births as an instrumental variable (IV) for fertility, I find that having children has a negative impact on female employment. In addition, three types of heterogeneity are found. First, the magnitude of the impact depends on the birth at which the increase in fertility takes place. Second, the types of jobs affected by a fertility shock (multiple births) are jobs identified with a higher degree of informality, such as self-employment or unpaid jobs. Finally, the heterogeneity analysis reveals that an unexpected change in fertility is stronger at a higher education level of the mother and in urban areas.

Reliability and Validity of Three Instruments (DSM-IV, CPGI, and PPGM) in the Assessment of Problem Gambling in South Korea.

PubMed

Back, Ki-Joon; Williams, Robert J; Lee, Choong-Ki

2015-09-01

Most research on the assessment, epidemiology, and treatment of problem gambling has occurred in Western jurisdictions. This potentially limits the cross-cultural validity of problem gambling assessment instruments as well as etiological models of problem gambling. The primary objective of the present research was to investigate the reliability and validity of three problem gambling assessment instruments within a South Korean context. A total of 4,330 South Korean adults participated in a comprehensive assessment of their gambling behavior that included the administration of the DSM-IV criteria for pathological gambling (NODS), the Canadian Problem Gambling Index (CPGI), and the Problem and Pathological Gambling Measure (PPGM). Cronbach alpha showed that all three instruments had good internal consistency. Concurrent validity was established by the significant associations observed between scores on the instruments and measures of gambling involvement (number of gambling formats engaged in; frequency of gambling; and gambling expenditure). Most importantly, kappa statistics showed that all instruments have satisfactory classification accuracy against clinical assessment of problem gambling conducted by South Korean clinicians (NODS κ = .66; PPGM κ = .62; CPGI κ = .51). These results confirm that Western-derived operationalizations of problem gambling have applicability in a South Korean setting.

Ocean Optics Protocols for Satellite Ocean Color Sensor Validation, Revision 4, Volume IV: Inherent Optical Properties: Instruments, Characterizations, Field Measurements and Data Analysis Protocols

NASA Technical Reports Server (NTRS)

Mueller, J. L.; Fargion, G. S.; McClain, C. R. (Editor); Pegau, S.; Zanefeld, J. R. V.; Mitchell, B. G.; Kahru, M.; Wieland, J.; Stramska, M.

2003-01-01

This document stipulates protocols for measuring bio-optical and radiometric data for the Sensor Intercomparision and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) Project activities and algorithm development. The document is organized into 6 separate volumes as Ocean Optics Protocols for Satellite Ocean Color Sensor Validation, Revision 4. Volume I: Introduction, Background, and Conventions; Volume II: Instrument Specifications, Characterization and Calibration; Volume III: Radiometric Measurements and Data Analysis Methods; Volume IV: Inherent Optical Properties: Instruments, Characterization, Field Measurements and Data Analysis Protocols; Volume V: Biogeochemical and Bio-Optical Measurements and Data Analysis Methods; Volume VI: Special Topics in Ocean Optics Protocols and Appendices. The earlier version of Ocean Optics Protocols for Satellite Ocean Color Sensor Validation, Revision 3 is entirely superseded by the six volumes of Revision 4 listed above.

Conscientiousness and obsessive-compulsive personality disorder.

PubMed

Samuel, Douglas B; Widiger, Thomas A

2011-07-01

A dimensional perspective on personality disorder hypothesizes that the current diagnostic categories represent maladaptive variants of general personality traits. However, a fundamental foundation of this viewpoint is that dimensional models can adequately account for the pathology currently described by these categories. While most of the personality disorders have well established links to dimensional models that buttress this hypothesis, obsessive-compulsive personality disorder (OCPD) has obtained only inconsistent support. The current study administered multiple measures of 1) conscientiousness-related personality traits, 2) DSM-IV OCPD, and 3) specific components of OCPD (e.g., compulsivity and perfectionism) to a sample of 536 undergraduates who were oversampled for elevated OCPD scores. Six existing measures of conscientiousness-related personality traits converged strongly with each other supporting their assessment of a common trait. These measures of conscientiousness correlated highly with scales assessing specific components of OCPD, but obtained variable relationships with measures of DSM-IV OCPD. More specifically, there were differences within the conscientiousness instruments such that those designed to assess general personality functioning had small to medium relationships with OCPD, but those assessing more maladaptive variants obtained large effect sizes. These findings support the view that OCPD does represent a maladaptive variant of normal-range conscientiousness.

Cardiovascular effects of pimobendan in healthy mature horses.

PubMed

Afonso, T; Giguère, S; Rapoport, G; Barton, M H; Coleman, A E

2016-05-01

Pimobendan is an inodilator used in dogs for the management of heart failure due to myxomatous valve disease or dilated cardiomyopathy. The lack of data regarding the effects of pimobendan in horses prevents the rational use of this drug. To determine the cardiovascular effects of pimobendan in healthy mature horses. Randomised experimental study. Five horses were fasted overnight prior to receiving i.v. pimobendan (0.25 mg/kg bwt), intragastric (i.g.) pimobendan (0.25 mg/kg bwt) or i.g. placebo with a washout period of one week between each administration. Horses were instrumented for the measurement of right ventricular (RV) minimum pressure, RV maximum pressure, RV end diastolic pressure, and maximum rate of increase and decrease in RV pressure before and 0.5, 1, 2, 4, and 8 h after drug administration. Arterial blood pressure, central venous pressure, cardiac output and heart rate were measured at the same time points. Data were expressed as a maximum percentage of change over baseline values. There were no adverse effects associated with administration of pimobendan. The percentage increase in heart rate was significantly greater for horses given pimobendan i.g. (33 ± 4%) and i.v. (36 ± 14%) than for those given a placebo (-2 ± 7%). The percentage increase in maximum rate of increase in RV pressure (35 ± 36%) and the percentage decrease in minimum pressure (47 ± 24%) and end diastolic pressure (34 ± 13%) were significantly greater in horses given pimobendan i.v. than in those given placebo. Other variables measured were not significantly different between treatment groups. Pimobendan administered i.v. has positive chronotropic and inotropic effects in healthy mature horses and warrants further investigation for the treatment of heart failure in horses. © 2015 EVJ Ltd.

Medical Spending and the Health of the Elderly

PubMed Central

Hadley, Jack; Waidmann, Timothy; Zuckerman, Stephen; Berenson, Robert A

2011-01-01

Objective To estimate the relationship between variations in medical spending and health outcomes of the elderly. Data Sources 1992–2002 Medicare Current Beneficiary Surveys. Study Design We used instrumental variable (IV) estimation to identify the relationships between alternative measures of elderly Medicare beneficiaries' medical spending over a 3-year observation period and health status, measured by the Health and Activity Limitation Index (HALex) and survival status at the end of the 3 years. We used the Dartmouth Atlas End-of-Life Expenditure Index defined for hospital referral regions in 1996 as the exogenous identifying variable to construct the IVs for medical spending. Data Collection/Extraction Methods The analysis sample includes 17,438 elderly (age >64) beneficiaries who entered the Medicare Current Beneficiary Survey in the fall of each year from 1991 to 1999, were not institutionalized at baseline, stayed in fee-for-service Medicare for the entire observation period, and survived for at least 2 years. Measures of baseline health were constructed from information obtained in the fall of the year the person entered the survey, and changes in health were from subsequent interviews over the entire observation period. Medicare and total medical spending were constructed from Medicare claims and self-reports of other spending over the entire observation period. Principal Findings IV estimation results in a positive and statistically significant relationship between medical spending and better health: 10 percent greater medical spending over the prior 3 years (mean = U.S.$2,709) is associated with a 1.9 percent larger HALex value (p = .045; range 1.2–2.2 percent depending on medical spending measure) and a 1.5 percent greater survival probability (p = .039; range 1.2–1.7 percent). Conclusions On average, greater medical spending is associated with better health status of Medicare beneficiaries, implying that across-the-board reductions in Medicare spending may result in poorer health for some beneficiaries. PMID:21609331

Estimation of treatment efficacy with complier average causal effects (CACE) in a randomized stepped wedge trial.

PubMed

Gruber, Joshua S; Arnold, Benjamin F; Reygadas, Fermin; Hubbard, Alan E; Colford, John M

2014-05-01

Complier average causal effects (CACE) estimate the impact of an intervention among treatment compliers in randomized trials. Methods used to estimate CACE have been outlined for parallel-arm trials (e.g., using an instrumental variables (IV) estimator) but not for other randomized study designs. Here, we propose a method for estimating CACE in randomized stepped wedge trials, where experimental units cross over from control conditions to intervention conditions in a randomized sequence. We illustrate the approach with a cluster-randomized drinking water trial conducted in rural Mexico from 2009 to 2011. Additionally, we evaluated the plausibility of assumptions required to estimate CACE using the IV approach, which are testable in stepped wedge trials but not in parallel-arm trials. We observed small increases in the magnitude of CACE risk differences compared with intention-to-treat estimates for drinking water contamination (risk difference (RD) = -22% (95% confidence interval (CI): -33, -11) vs. RD = -19% (95% CI: -26, -12)) and diarrhea (RD = -0.8% (95% CI: -2.1, 0.4) vs. RD = -0.1% (95% CI: -1.1, 0.9)). Assumptions required for IV analysis were probably violated. Stepped wedge trials allow investigators to estimate CACE with an approach that avoids the stronger assumptions required for CACE estimation in parallel-arm trials. Inclusion of CACE estimates in stepped wedge trials with imperfect compliance could enhance reporting and interpretation of the results of such trials.

Eliminating Survivor Bias in Two-stage Instrumental Variable Estimators.

PubMed

Vansteelandt, Stijn; Walter, Stefan; Tchetgen Tchetgen, Eric

2018-07-01

Mendelian randomization studies commonly focus on elderly populations. This makes the instrumental variables analysis of such studies sensitive to survivor bias, a type of selection bias. A particular concern is that the instrumental variable conditions, even when valid for the source population, may be violated for the selective population of individuals who survive the onset of the study. This is potentially very damaging because Mendelian randomization studies are known to be sensitive to bias due to even minor violations of the instrumental variable conditions. Interestingly, the instrumental variable conditions continue to hold within certain risk sets of individuals who are still alive at a given age when the instrument and unmeasured confounders exert additive effects on the exposure, and moreover, the exposure and unmeasured confounders exert additive effects on the hazard of death. In this article, we will exploit this property to derive a two-stage instrumental variable estimator for the effect of exposure on mortality, which is insulated against the above described selection bias under these additivity assumptions.

Higher Order, Multisample, Confirmatory Factor Analysis of the Wechsler Intelligence Scale for Children--Fourth Edition: What Does It Measure?

ERIC Educational Resources Information Center

Keith, Timothy Z.; Fine, Jodene Goldenring; Taub, Gordon E.; Reynolds, Matthew R.; Kranzler, John H.

2006-01-01

The recently published fourth edition of the Wechsler Intelligence Scale for Children (WISC-IV) represents a considerable departure from previous versions of the scale. The structure of the instrument has changed, and some subtests have been added and others deleted. The technical manual for the WISC-IV provided evidence supporting this new…

Use of the Panic Attack Questionnaire-IV to assess non-clinical panic attacks and limited symptom panic attacks in student and community samples.

PubMed

Norton, Peter J; Zvolensky, Michael J; Bonn-Miller, Marcel O; Cox, Brian J; Norton, G Ron

2008-10-01

Since its development in the mid-1980s, the Panic Attack Questionnaire (PAQ) has been one of the more, if not the most, commonly used self-report tools for assessing panic attacks. The usage of the instrument, however, has come amid potential concerns that instructions and descriptions may lead to an over-estimate of the prevalence of panic attacks. Furthermore, the instrument has not been revised since 1992, despite changes in DSM-IV criteria and more recent developments in the understanding of panic attacks. As a result, this paper describes a revision of the PAQ to improve the instruction and descriptive set, and to fully assess features of panic derived from recent conceptualizations. Students meeting DSM-IV panic attack criteria and those endorsing panic attacks, but not meeting criteria, showed few differences with the exception that those not meeting DSM-IV criteria typically reported a longer onset-to-peak intensity time than did Panickers. Results were cross-validated and extended using an independent Community Sample. A full descriptive phenomenology of panic attacks is described, and future directions for studying panic attacks using the PAQ are presented.

Internal variability of fine-scale components of meteorological fields in extended-range limited-area model simulations with atmospheric and surface nudging

NASA Astrophysics Data System (ADS)

Separovic, Leo; Husain, Syed Zahid; Yu, Wei

2015-09-01

Internal variability (IV) in dynamical downscaling with limited-area models (LAMs) represents a source of error inherent to the downscaled fields, which originates from the sensitive dependence of the models to arbitrarily small modifications. If IV is large it may impose the need for probabilistic verification of the downscaled information. Atmospheric spectral nudging (ASN) can reduce IV in LAMs as it constrains the large-scale components of LAM fields in the interior of the computational domain and thus prevents any considerable penetration of sensitively dependent deviations into the range of large scales. Using initial condition ensembles, the present study quantifies the impact of ASN on IV in LAM simulations in the range of fine scales that are not controlled by spectral nudging. Four simulation configurations that all include strong ASN but differ in the nudging settings are considered. In the fifth configuration, grid nudging of land surface variables toward high-resolution surface analyses is applied. The results show that the IV at scales larger than 300 km can be suppressed by selecting an appropriate ASN setup. At scales between 300 and 30 km, however, in all configurations, the hourly near-surface temperature, humidity, and winds are only partly reproducible. Nudging the land surface variables is found to have the potential to significantly reduce IV, particularly for fine-scale temperature and humidity. On the other hand, hourly precipitation accumulations at these scales are generally irreproducible in all configurations, and probabilistic approach to downscaling is therefore recommended.

Criteria for choosing an intravenous infusion line intended for multidrug infusion in anaesthesia and intensive care units.

PubMed

Maiguy-Foinard, Aurélie; Genay, Stéphanie; Lannoy, Damien; Barthélémy, Christine; Lebuffe, Gilles; Debaene, Bertrand; Odou, Pascal; Décaudin, Bertrand

2017-02-01

The aims are to identify critical parameters influencing the drug mass flow rate of infusion delivery to patients during multidrug infusion and to discuss their clinical relevance. A review of literature was conducted in January 2016 using Medline, Google Scholar, ScienceDirect, Web of Science and Scopus online databases. References relating to the accuracy of fluid delivery via gravity-flow intravenous (IV) infusion systems and positive displacement pumps, components of IV administration sets, causes of flow rate variability, potential complications due to flow rate variability, IV therapies especially at low flow rates and drug compatibilities were considered relevant. Several parameters impact the delivery of drugs and fluids by IV infusion. Among them are the components of infusion systems that particularly influence the flow rate of medications and fluids being delivered. By their conception, they may generate significant start-up delays and flow rate variability. Performing multidrug infusion requires taking into account two main points: the common dead volume of drugs delivered simultaneously with potential consequences on the accuracy and amount of drug delivery and the prevention of drug incompatibilities and their clinical effects. To prevent the potentially serious effects of flow rate variability on patients, clinicians should receive instruction on the fluid dynamics of an IV administration set and so be able to take steps to minimise flow rate changes during IV therapy. Copyright © 2016 Société française d’anesthésie et de réanimation (Sfar). Published by Elsevier Masson SAS. All rights reserved.

The UK Infrared Telescope M33 monitoring project - IV. Variable red giant stars across the galactic disc

NASA Astrophysics Data System (ADS)

Javadi, Atefeh; Saberi, Maryam; van Loon, Jacco Th.; Khosroshahi, Habib; Golabatooni, Najmeh; Mirtorabi, Mohammad Taghi

2015-03-01

We have conducted a near-infrared monitoring campaign at the UK InfraRed Telescope, of the Local Group spiral galaxy M33 (Triangulum). The main aim was to identify stars in the very final stage of their evolution, and for which the luminosity is more directly related to the birth mass than the more numerous less-evolved giant stars that continue to increase in luminosity. In this fourth paper of the series, we present a search for variable red giant stars in an almost square degree region comprising most of the galaxy's disc, carried out with the WFCAM (Wide Field CAMera) instrument in the K band. These data, taken during the period 2005-2007, were complemented by J- and H-band images. Photometry was obtained for 403 734 stars in this region; of these, 4643 stars were found to be variable, most of which are asymptotic giant branch (AGB) stars. The variable stars are concentrated towards the centre of M33, more so than low-mass, less-evolved red giants. Our data were matched to optical catalogues of variable stars and carbon stars and to mid-infrared photometry from the Spitzer Space Telescope. Most dusty AGB stars had not been previously identified in optical variability surveys, and our survey is also more complete for these types of stars than the Spitzer survey. The photometric catalogue is made publicly available at the Centre de Données astronomiques de Strasbourg.

Can Monitoring Fetal Intestinal Inflammation Using Heart Rate Variability Analysis Signal Incipient Necrotizing Enterocolitis of the Neonate?

PubMed

Liu, Hai Lun; Garzoni, Luca; Herry, Christophe; Durosier, Lucien Daniel; Cao, Mingju; Burns, Patrick; Fecteau, Gilles; Desrochers, André; Patey, Natalie; Seely, Andrew J E; Faure, Christophe; Frasch, Martin G

2016-04-01

Necrotizing enterocolitis of the neonate is an acute inflammatory intestinal disease that can cause necrosis and sepsis. Chorioamnionitis is a risk factor of necrotizing enterocolitis. The gut represents the biggest vagus-innervated organ. Vagal activity can be measured via fetal heart rate variability. We hypothesized that fetal heart rate variability can detect fetuses with incipient gut inflammation. Prospective animal study. University research laboratory. Chronically instrumented near-term fetal sheep (n = 21). Animals were surgically instrumented with vascular catheters and electrocardiogram to allow manipulation and recording from nonanesthetized animals. In 14 fetal sheep, inflammation was induced with lipopolysaccharide (IV) to mimic chorioamnionitis. Fetal arterial blood samples were drawn at selected time points over 54 hours post lipopolysaccharide for blood gas and cytokines (interleukin-6 and tumor necrosis factor-α enzymelinked immunosorbent assay). Fetal heart rateV was quantified throughout the experiment. The time-matched fetal heart rate variability measures were correlated to the levels of interleukin-6 and tumor necrosis factor-α. Upon necropsy, ionized calcium binding adaptor molecule 1+ (Iba1+), CD11c+ (M1), CD206+ (M2 macrophages), and occludin (leakiness marker) immunofluorescence in the terminal ileum was quantified along with regional Iba1+ signal in the brain (microglia). Interleukin-6 peaked at 3 hours post lipopolysaccharide accompanied by mild cardiovascular signs of sepsis. At 54 hours, we identified an increase in Iba1+ and, specifically, M1 macrophages in the ileum accompanied by increased leakiness, with no change in Iba1 signal in the brain. Preceding this change on tissue level, at 24 hours, a subset of nine fetal heart rate variability measures correlated exclusively to the Iba+ markers of ileal, but not brain, inflammation. An additional fetal heart rate variability measure, mean of the differences of R-R intervals, correlated uniquely to M1 ileum macrophages increasing due to lipopolysaccharide. We identified a unique subset of fetal heart rate variability measures reflecting 1.5 days ahead of time the levels of macrophage activation and increased leakiness in terminal ileum. We propose that such subset of fetal heart rate variability measures reflects brain-gut communication via the vagus nerve. Detecting such noninvasively obtainable organ-specific fetal heart rate variability signature of inflammation would alarm neonatologists about neonates at risk of developing necrotizing enterocolitis and sepsis. Clinical validation studies are required.

The oculo-dento-digital syndrome: male-to-male transmission and variable expression in a family.

PubMed

Ioan, D M; Dumitriu, L; Belengeariu, V; Fryns, J P

1997-01-01

We report two siblings--a 5 1/2 year old female and her 4 1/2 year old brother, both presenting the classical clinical findings of oculo-dento-digital dysplasia (ODD). 1. Digital anomalies: bilateral complete cutaneous syndactyly of fingers IV-V (III-IV-V at the left hand of the boy) and camptodactyly IV. 2. Facial and ocular anomalies: microphtalamos-epicanthal folds, small midfacies, thin nose with hypoplastic alae nasi and small nares. 3. Dental anomalies with partial dental agenesis and enamel hypoplasia. Examination of the parents showed a bilateral cutaneous syndactyly IV-V in the father as the sole partial manifestation of ODD. The findings in the present family confirm the autosomal dominant inheritance of ODD with great variability in clinical expression. Moreover, the facial morphology (thin, hypoplastic nose) observed in several ODD patients suggests nosological overlap with the Hallerman-Streiff syndrome and could indicate that both syndromes are variable expressions of a contiguous gene deletion syndrome.

7 CFR 3575.52 - Processing.

Code of Federal Regulations, 2010 CFR

2010-01-01

... applicable); (iii) Supporting documentation necessary to make an eligibility determination such as financial statements, audits, copies of organizational documents, existing debt instruments, etc.; and (iv...

Implementation of Instrumental Variable Bounds for Data Missing Not at Random.

PubMed

Marden, Jessica R; Wang, Linbo; Tchetgen, Eric J Tchetgen; Walter, Stefan; Glymour, M Maria; Wirth, Kathleen E

2018-05-01

Instrumental variables are routinely used to recover a consistent estimator of an exposure causal effect in the presence of unmeasured confounding. Instrumental variable approaches to account for nonignorable missing data also exist but are less familiar to epidemiologists. Like instrumental variables for exposure causal effects, instrumental variables for missing data rely on exclusion restriction and instrumental variable relevance assumptions. Yet these two conditions alone are insufficient for point identification. For estimation, researchers have invoked a third assumption, typically involving fairly restrictive parametric constraints. Inferences can be sensitive to these parametric assumptions, which are typically not empirically testable. The purpose of our article is to discuss another approach for leveraging a valid instrumental variable. Although the approach is insufficient for nonparametric identification, it can nonetheless provide informative inferences about the presence, direction, and magnitude of selection bias, without invoking a third untestable parametric assumption. An important contribution of this article is an Excel spreadsheet tool that can be used to obtain empirical evidence of selection bias and calculate bounds and corresponding Bayesian 95% credible intervals for a nonidentifiable population proportion. For illustrative purposes, we used the spreadsheet tool to analyze HIV prevalence data collected by the 2007 Zambia Demographic and Health Survey (DHS).

Cross-section and panel estimates of peer effects in early adolescent cannabis use: With a little help from my 'friends once removed'.

PubMed

Moriarty, John; McVicar, Duncan; Higgins, Kathryn

2016-08-01

Peer effects in adolescent cannabis are difficult to estimate, due in part to the lack of appropriate data on behaviour and social ties. This paper exploits survey data that have many desirable properties and have not previously been used for this purpose. The data set, collected from teenagers in three annual waves from 2002 to 2004 contains longitudinal information about friendship networks within schools (N = 5020). We exploit these data on network structure to estimate peer effects on adolescents from their nominated friends within school using two alternative approaches to identification. First, we present a cross-sectional instrumental variable (IV) estimate of peer effects that exploits network structure at the second degree, i.e. using information on friends of friends who are not themselves ego's friends to instrument for the cannabis use of friends. Second, we present an individual fixed effects estimate of peer effects using the full longitudinal structure of the data. Both innovations allow a greater degree of control for correlated effects than is commonly the case in the substance-use peer effects literature, improving our chances of obtaining estimates of peer effects than can be plausibly interpreted as causal. Both estimates suggest positive peer effects of non-trivial magnitude, although the IV estimate is imprecise. Furthermore, when we specify identical models with behaviour and characteristics of randomly selected school peers in place of friends', we find effectively zero effect from these 'placebo' peers, lending credence to our main estimates. We conclude that cross-sectional data can be used to estimate plausible positive peer effects on cannabis use where network structure information is available and appropriately exploited. Copyright © 2016 Elsevier Ltd. All rights reserved.

A Taxometric Investigation of "DSM-IV" Major Depression in a Large Outpatient Sample: Interpretable Structural Results Depend on the Mode of Assessment

ERIC Educational Resources Information Center

Ruscio, John; Brown, Timothy A.; Ruscio, Ayelet Meron

2009-01-01

Most taxometric studies of depressive constructs have drawn indicators from self-report instruments that do not bear directly on the "Diagnostic and Statistical Manual of Mental Disorders, 4th edition (DSM-IV)" diagnostic construct of major depressive disorder (MDD). The present study examined the latent structure of MDD using indicator sets…

Analysis of School Leaders Licensure Assessment Content Category I-V Scores and Principal Internship Self-Assessment Scores for ISLLC Standards I-V

ERIC Educational Resources Information Center

Kelly, Michael D.

2016-01-01

This study compares School Leaders Licensure Assessment (SLLA) sub-scores with principal interns' self-assessment sub-scores (ISA) for a principal internship evaluation instrument in one educational leadership graduate program. The results of the study will be used to help establish the effectiveness of the current principal internship program,…

Preliminary Design of Critical Function Monitoring System of PGSFR

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

NONE

2015-07-01

A PGSFR (Prototype Gen-IV Sodium-cooled Fast Reactor) is under development at Korea Atomic Energy Research Institute. A critical function monitoring system of the PGSFR is preliminarily studied. The functions of CFMS are to display critical plant variables related to the safety of the plant during normal and accident conditions and guide the operators corrective actions to keep the plant in a safe condition and mitigate the consequences of accidents. The minimal critical functions of the PGSFR are composed of reactivity control, reactor core cooling, reactor coolant system integrity, primary heat transfer system(PHTS) heat removal, sodium water reaction mitigation, radiation controlmore » and containment conditions. The variables and alarm legs of each critical function of the PGSFR are as follows; - Reactivity control: The variables of reactivity control function are power range neutron flux instrumentation, intermediate range neutron flux instrumentation, source range neutron flux instrumentation, and control rod bottom contacts. The alarm leg to display the reactivity controls consists of status of control drop malfunction, high post trip power and thermal reactivity addition. - Reactor core cooling: The variables are PHTS sodium level, hot pool temperature of PHTS, subassembly exit temperature, cold pool temperature of the PHTS, PHTS pump current, and PHTS pump breaker status. The alarm leg consists of high core delta temperature, low sodium level of the PHTS, high subassembly exit temperature, and low PHTS pump load. - Reactor coolant system integrity: The variables are PHTS sodium level, cover gas pressure, and safeguard vessel sodium level. The alarm leg is composed of low sodium level of PHTS, high cover gas pressure and high sodium level of the safety guard vessel. - PHTS heat removal: The variables are PHTS sodium level, hot pool temperature of PHTS, core exit temperature, cold pool temperature of the PHTS, flow rate of passive residual heat removal system, flow rate of active residual heat removal system, and temperatures of air heat exchanger temperature of residual heat removal systems. The alarm legs are composed of two legs of a 'passive residual heat removal system not cooling' and 'active residual heat removal system not cooling'. - Sodium water reaction mitigation: The variables are intermediate heat transfer system(IHTS) pressure, pressure and temperature and level of sodium dump tank, the status of rupture disk, hydrogen concentration in IHTS and direct variable of sodium-water-reaction measure. The alarm leg consists of high IHTS pressure, the status of sodium water reaction mitigation system and the indication of direct measure. - Radiation control: The variables are radiation of PHTS, radiation of IHTS, and radiation of containment purge. The alarm leg is composed of high radiation of PHTS and IHTS, and containment purge system. - Containment condition: The variables are containment pressure, containment isolation status, and sodium fire. The alarm leg consists of high containment pressure, status of containment isolation and status of sodium fire. (authors)« less

Developments in Post-marketing Comparative Effectiveness Research

PubMed Central

S, Schneeweiss

2010-01-01

Physicians and insurers need to weigh the effectiveness of new drugs against existing therapeutics in routine care to make decisions about treatment and formularies. Because Food and Drug Administration (FDA) approval of most new drugs requires demonstrating efficacy and safety against placebo, there is limited interest by manufacturers in conducting such head-to-head trials. Comparative effectiveness research seeks to provide head-to-head comparisons of treatment outcomes in routine care. Health-care utilization databases record drug use and selected health outcomes for large populations in a timely way and reflect routine care, and therefore may be the preferred data source for comparative effectiveness research. Confounding caused by selective prescribing based on indication, severity, and prognosis threatens the validity of non-randomized database studies that often have limited details on clinical information. Several recent developments may bring the field closer to acceptable validity, including approaches that exploit the concepts of proxy variables using high-dimensional propensity scores, within-patient variation of drug exposure using crossover designs, and between-provider variation in prescribing preference using instrumental variable (IV) analyses. PMID:17554243

Developments in post-marketing comparative effectiveness research.

PubMed

Schneeweiss, S

2007-08-01

Physicians and insurers need to weigh the effectiveness of new drugs against existing therapeutics in routine care to make decisions about treatment and formularies. Because Food and Drug Administration (FDA) approval of most new drugs requires demonstrating efficacy and safety against placebo, there is limited interest by manufacturers in conducting such head-to-head trials. Comparative effectiveness research seeks to provide head-to-head comparisons of treatment outcomes in routine care. Health-care utilization databases record drug use and selected health outcomes for large populations in a timely way and reflect routine care, and therefore may be the preferred data source for comparative effectiveness research. Confounding caused by selective prescribing based on indication, severity, and prognosis threatens the validity of non-randomized database studies that often have limited details on clinical information. Several recent developments may bring the field closer to acceptable validity, including approaches that exploit the concepts of proxy variables using high-dimensional propensity scores, within-patient variation of drug exposure using crossover designs, and between-provider variation in prescribing preference using instrumental variable (IV) analyses.

Multiple Intravenous Infusions Phase 2a: Ontario Survey

PubMed Central

Fan, Mark; Koczmara, Christine; Masino, Caterina; Cassano-Piché, Andrea; Trbovich, Patricia; Easty, Anthony

2014-01-01

Background Research conducted in earlier phases of this study prospectively identified a number of concerns related to the safe administration of multiple intravenous (IV) infusions in Ontario hospitals. Objective To investigate the potential prevalence of practices or policies that may contribute to the patient safety risks identified in Phase 1b of this study. Data Sources and Review Methods Sixty-four survey responses were analyzed from clinical units where multiple IV infusions may occur (e.g., adult intensive care units). Survey questions were organized according to the topics identified in Phase 1b as potential contributors to patient harm (e.g., labelling practices, patient transfer practices, secondary infusion policies). Results Survey results indicated suboptimal practices and policies in some clinical units, and variability in a number of infusion practices. Key areas of concern included the following: use of primary IV tubing without back check valves when administering secondary infusions administration of secondary infusions with/as high-alert continuous IV medications potential confusion about how IV tubing should be labelled to reflect replacement date and time interruptions to IV therapy due to IV pump and/or tubing changes when patients are transferred between clinical units coadministration of continuous or intermittent infusions on central venous pressure monitoring ports variability in respondents’ awareness of the infusion pump's bolus capabilities Limitations Due to the limited sample size, survey responses may not be representative of infusion practices across Ontario. Answers to some questions indicated that the intent of the questions might have been misunderstood. Due to a design error, 1 question about bolus administration methods was not shown to as many respondents as appropriate. Conclusions The Ontario survey revealed variability in IV infusion practice across the province and potential opportunities to improve safety. PMID:26257837

Physical fitness predicts technical-tactical and time-motion profile in simulated Judo and Brazilian Jiu-Jitsu matches

PubMed Central

Gentil, Paulo; Bueno, João C.A.; Follmer, Bruno; Marques, Vitor A.; Del Vecchio, Fabrício B.

2018-01-01

Background Among combat sports, Judo and Brazilian Jiu-Jitsu (BJJ) present elevated physical fitness demands from the high-intensity intermittent efforts. However, information regarding how metabolic and neuromuscular physical fitness is associated with technical-tactical performance in Judo and BJJ fights is not available. This study aimed to relate indicators of physical fitness with combat performance variables in Judo and BJJ. Methods The sample consisted of Judo (n = 16) and BJJ (n = 24) male athletes. At the first meeting, the physical tests were applied and, in the second, simulated fights were performed for later notational analysis. Results The main findings indicate: (i) high reproducibility of the proposed instrument and protocol used for notational analysis in a mobile device; (ii) differences in the technical-tactical and time-motion patterns between modalities; (iii) performance-related variables are different in Judo and BJJ; and (iv) regression models based on metabolic fitness variables may account for up to 53% of the variances in technical-tactical and/or time-motion variables in Judo and up to 31% in BJJ, whereas neuromuscular fitness models can reach values up to 44 and 73% of prediction in Judo and BJJ, respectively. When all components are combined, they can explain up to 90% of high intensity actions in Judo. Discussion In conclusion, performance prediction models in simulated combat indicate that anaerobic, aerobic and neuromuscular fitness variables contribute to explain time-motion variables associated with high intensity and technical-tactical variables in Judo and BJJ fights. PMID:29844991

The role of psychological processes in estimates of stuttering severity.

PubMed

Manning, Walter; Gayle Beck, J

2013-12-01

To examine the associations of trait anxiety (STAI), social anxiety (SIAS), depression (BDI-II), and personality features (ADP-IV) with three measures of stuttering severity: %SS, Stuttering Severity, Instrument, and the Overall Assessment of the Speaker's Experience of Stuttering. Fifty adults with a history of stuttering served as participants. Participant scores on trait, anxiety, social anxiety, depression, and personality features were entered into a regression analysis, with the criterion variables (DVs) being: %SS, SSI-3, OASES total score. In order to explore the OASES, further, each of the four OASES subscales were also examined. A separate regression was conducted for, each dependent variable. The OASES total score model was significant (p<.0001) and revealed that social anxiety and, trait anxiety were the only significant predictors, with medium effect sizes noted for both variables. In contrast, percent syllables stuttered and the SSI were not significantly associated with psychological, variables, suggesting that anxiety may not always be related to overt indicators of stuttering. Depression and personality dysfunction were not significantly associated with any measure of, stuttering severity. Anxiety in the form of social and trait anxiety are significantly associated with stuttering, severity as indicated by the OASES. Traditional procedures for assigning severity ratings to individuals, who stutter based on percent syllables stuttered and the Stuttering Severity Instrument are not, significantly related to psychological processes central to the stuttering experience. Depression and, personality characteristics do not meaningfully account for stuttering. The reader will be able to: (a) differentiate forms of anxiety that are likely to be associated with stuttering (b) understand the importance of determining features of stuttering that go beyond the obvious, surface characteristics of stuttering frequency, and (c) discuss the important clinical and theoretical implications for understanding the degree of psychological dysfunction that is likely to be characteristic of those who stutter. Copyright © 2013 Elsevier Inc. All rights reserved.

Relationships between convective storms and their environment in AVE IV determined from a three-dimensional subsynoptic-scale, trajectory model

NASA Technical Reports Server (NTRS)

Wilson, G. S.

1977-01-01

The paper describes interrelationships between synoptic-scale and convective-scale systems obtained by following individual air parcels as they traveled within the convective storm environment of AVE IV. (NASA's fourth Atmospheric Variability Experiment, AVE IV, was a 36-hour study in April 1975 of the atmospheric variability and structure in regions of convective storms.) A three-dimensional trajectory model was used to calculate parcel paths, and manually digitized radar was employed to locate convective activity of various intensities and to determine those trajectories that traversed the storm environment. Spatial and temporal interrelationships are demonstrated by reference to selected time periods of AVE IV which contain the development and movement of the squall line in which the Neosho tornado was created.

Content Aggregations for Reading Skills and Mathematics for the Comparative Study of Phase IV of the IGE Evaluation Project. Phase IV, Project Paper 80-3.

ERIC Educational Resources Information Center

Nerenz, Anne G.; Webb, Norman L.

This is one of a series of reports which provide definitions of and descriptive data on the variables used in the Comparative Study of Phase IV of the Individually Guided Education (IEG) Evaluation Project. Phase IV investigated three curriculum programs specifically designed to be compatible with instructional programming for the individual…

Effects of women's autonomy on maternal healthcare utilization in Bangladesh: Evidence from a national survey.

PubMed

Haider, Mohammad Rifat; Qureshi, Zaina P; Khan, M Mahmud

2017-12-01

This study aims to construct an index of women's autonomy to analyze its effect on maternal healthcare utilization in Bangladesh. Empirical modeling of the study used instrumental variable (IV) approach to correct for possible endogeneity of women's autonomy variable. Data from the Bangladesh Demographic and Health Survey (BDHS) 2011 was used for the study. Women's autonomy variable was obtained through factor analysis of variables related to autonomy in decision making regarding healthcare, financial autonomy and freedom of movement. Conditional mixed process (CMP) models were fitted for three maternal healthcare indicators: at least four antenatal care (ANC) by trained personnel, institutional delivery and postnatal care (PNC) by trained personnel. Study sample consisted of 8753 women with 5.5 mean years of schooling. Women with no formal education, of Islamic faith, from poorest wealth quintile, residing in rural areas and with low autonomy used the maternal healthcare least. Marginal effect shows that if women's autonomy score is increased by one unit, probability of maternal healthcare utilization will increase by 0.14 for ANC, 0.14 for institutional delivery, and 0.13 for PNC. Women's autonomy is an important driver of maternal healthcare utilization in Bangladesh. Results suggest that women participating in social and economic activities enhances their autonomy. Other factors affecting women's autonomy are female literacy, educational attainment and households' economic status. Copyright © 2017 Elsevier B.V. All rights reserved.

Power calculator for instrumental variable analysis in pharmacoepidemiology

PubMed Central

Walker, Venexia M; Davies, Neil M; Windmeijer, Frank; Burgess, Stephen; Martin, Richard M

2017-01-01

Abstract Background Instrumental variable analysis, for example with physicians’ prescribing preferences as an instrument for medications issued in primary care, is an increasingly popular method in the field of pharmacoepidemiology. Existing power calculators for studies using instrumental variable analysis, such as Mendelian randomization power calculators, do not allow for the structure of research questions in this field. This is because the analysis in pharmacoepidemiology will typically have stronger instruments and detect larger causal effects than in other fields. Consequently, there is a need for dedicated power calculators for pharmacoepidemiological research. Methods and Results The formula for calculating the power of a study using instrumental variable analysis in the context of pharmacoepidemiology is derived before being validated by a simulation study. The formula is applicable for studies using a single binary instrument to analyse the causal effect of a binary exposure on a continuous outcome. An online calculator, as well as packages in both R and Stata, are provided for the implementation of the formula by others. Conclusions The statistical power of instrumental variable analysis in pharmacoepidemiological studies to detect a clinically meaningful treatment effect is an important consideration. Research questions in this field have distinct structures that must be accounted for when calculating power. The formula presented differs from existing instrumental variable power formulae due to its parametrization, which is designed specifically for ease of use by pharmacoepidemiologists. PMID:28575313

Compliance-Effect Correlation Bias in Instrumental Variables Estimators

ERIC Educational Resources Information Center

Reardon, Sean F.

2010-01-01

Instrumental variable estimators hold the promise of enabling researchers to estimate the effects of educational treatments that are not (or cannot be) randomly assigned but that may be affected by randomly assigned interventions. Examples of the use of instrumental variables in such cases are increasingly common in educational and social science…

Assessment Inventories, Surveys, and Templates for Evaluating Educational Technology Regional and Local Assistance Programs. Phase IV of the Comprehensive Study of Educational Technology Programs Authorized from 1984-1992.

ERIC Educational Resources Information Center

Far West Lab. for Educational Research and Development, San Francisco, CA.

This report on Phase IV, of a four-phase study, provided for the development of evaluation templates and instruments to be used by the California Department of Education to facilitate systematic assessment of state funded educational technology programs and projects. These assessment documents comprised the major data collection sources for the…

Linking measures of adolescent nicotine dependence to a common latent continuum.

PubMed

Strong, David R; Kahler, Christopher W; Colby, Suzanne M; Griesler, Pamela C; Kandel, Denise

2009-01-01

Using the theoretical model of nicotine dependence (ND) operationalized within the Diagnostic and Statistical Manual of Mental Disorder, fourth Edition (DSM-IV: American Psychiatric [American Psychiatric Association, 1994. Diagnostic and Statistical Manual of Mental Disorders. 4th ed. American Psychiatric Association, Washington, DC]) as a frame of reference, we used methods based in item response theory to link alternative instruments assessing adolescent nicotine dependence severity to a common latent continuum. A multi-ethnic cohort of 6th-10th graders selected from the Chicago Public Schools (CPS) completed five household interviews over 2 years. Youth who reported at least some cigarette use in the last 30 days prior to the interviews at waves W3-W5 completed measures of DSM-IV ND, the Modified Fagertrom Tolerance Questionnaire (mFTQ: Prokhorov et al., 1998) and the Nicotine Dependence Syndrome Scale (NDSS: Shiffman et al., 2004), yielding samples of 253, 241, and 296 respondents at W3-W5, respectively. Confirmatory factor analysis supported a primary dimension of ND. Each instrument's items had complementary and stable relationships to ND across multiple waves of assessment. By aligning symptoms along a common latent ND continuum, we evaluated the consistency of symptoms from different instruments that target similar content. Further, these methods allowed for the examination of the DSM-IV as a continuous index of ND, evaluation of the degree of heterogeneity in levels of ND within groups above and below diagnostic thresholds, and the utility of using the pattern or particular DSM-IV symptoms that led to each score in further differentiating levels of ND. Finally, we examined concurrent validity of the ND continuum and levels of current of smoking at each wave of assessment.

Goddard High Resolution Spectrograph Observations of Variability in the RS Canum Venaticorum System V711 Tauri (HR 1099)

NASA Technical Reports Server (NTRS)

Dempsey, Robert C.; Neff, James E.; Thorpe, Marjorie J.; Linsky, Jeffrey L.; Brown, Alexander; Cutispoto, Giuseppe; Rodono, Marcello

1996-01-01

Goddard High Resolution Spectrograph (GHRS) observations of the RS CVn-type binary V711 Tau (Kl IV+G5 IV) were obtained at several phases over two consecutive stellar orbital cycles in order to study ultraviolet emission-line profile and flux variability. Spectra cover the Mg II h and k lines, C IV doublet, and Si IV region, as well as the density-sensitive lines of C III] (1909 A) and Si III] (1892 A). IUE spectra, Extreme Ultra Violet (EUV) data, and Ultraviolet, Blue, Visual (UBV) photometry were obtained contemporaneously with the GHRS data. Variable extended wings were detected in the Mg II lines. We discuss the Mg II line profile variability using various Gaussian emission profile models. No rotational modulation of the line profiles was observed, but there were several large flares. These flares produced enhanced emission in the extended line wings, radial velocity shifts, and asymmetries in some line profiles. Nearly continuous flaring for more than 24 hr, as indicated in the IUE data, represents the most energetic and long-lived chromospheric and transition region flare ever observed with a total energy much greater than 5 x 10(exp 35) ergs. The C III] to Si III] line ratio is used to estimate the plasma density during the flares.

The Reliability and Criterion Validity of the Diagnostic Infant and Preschool Assessment: A New Diagnostic Instrument for Young Children

ERIC Educational Resources Information Center

Scheeringa, Michael S.; Haslett, Nancy

2010-01-01

The need to assess Diagnostic and Statistical Manual, Fourth Edition (DSM-IV) disorders in children younger than 7 years of age has intensified as clinical efforts to diagnose and treat this population have increased, and clinical research on psychopathology has advanced. A new diagnostic instrument for young children was created, the Diagnostic…

The Dark Energy Spectroscopic Instrument (DESI)

NASA Astrophysics Data System (ADS)

Flaugher, Brenna; Bebek, Chris

2014-07-01

The Dark Energy Spectroscopic Instrument (DESI) is a Stage IV ground-based dark energy experiment that will study baryon acoustic oscillations (BAO) and the growth of structure through redshift-space distortions with a wide-area galaxy and quasar spectroscopic redshift survey. The DESI instrument consists of a new wide-field (3.2 deg. linear field of view) corrector plus a multi-object spectrometer with up to 5000 robotically positioned optical fibers and will be installed at prime focus on the Mayall 4m telescope at Kitt Peak, Arizona. The fibers feed 10 three-arm spectrographs producing spectra that cover a wavelength range from 360-980 nm and have resolution of 2000-5500 depending on the wavelength. The DESI instrument is designed for a 14,000 sq. deg. multi-year survey of targets that trace the evolution of dark energy out to redshift 3.5 using the redshifts of luminous red galaxies (LRGs), emission line galaxies (ELGs) and quasars. DESI is the successor to the successful Stage-III BOSS spectroscopic redshift survey and complements imaging surveys such as the Stage-III Dark Energy Survey (DES, currently operating) and the Stage-IV Large Synoptic Survey Telescope (LSST, planned start early in the next decade).

Effect of hot carcass weight on loin, ham, and belly quality from pigs sourced from a commercial processing facility,.

PubMed

Harsh, B N; Arkfeld, E K; Mohrhauser, D A; King, D A; Wheeler, T L; Dilger, A C; Shackelford, S D; Boler, D D

2017-11-01

The objective was to determine the predictive abilities of HCW for loin, ham, and belly quality of 7,684 pigs with carcass weights ranging from 53.2 to 129.6 kg. Carcass composition, subjective loin quality, and ham face color were targeted on all carcasses, whereas in-plant instrumental loin color and belly quality were assessed on 52.0 and 47.5% of carcasses, respectively. Loin chop slice shear force (SSF), cured ham quality, and adipose iodine value (IV) were evaluated on at least 10% of the population. The slope of regression lines and coefficients of determination between HCW and quality traits were computed using PROC REG of SAS and considered significant at ≤ 0.05. As HCW increased, boneless loins became darker and redder, evidenced by lower L* (β = -0.0243, < 0.001) and greater a* values (β = 0.0106, < 0.001); however, HCW accounted for only ≤0.80% of the variability in loin L* and a* values. Similarly, subjective loin color score (β = 0.0024, < 0.001) increased with increasing carcass weight, but subjective marbling score was not affected by HCW (β = -0.0022, = 0.06). After 20 d of aging, HCW explained only 0.98% of the variability in loin L* values (β = -0.0287, < 0.01). Heavier carcasses had lower SSF values (β = -0.1269, < 0.001) of LM chops, although HCW explained only 4.46% of the variability in SSF. Although heavier carcasses produced loins that exhibited lower ultimate pH values (β = -0.0018, < 0.001), HCW explained only 1.23% of the variability in ultimate loin pH. Interestingly, cook loss decreased (β = -0.0521, < 0.001) as HCW increased, with HCW accounting for 5.60% of the variability in cook loss. Heavier carcasses resulted in darker, redder ham face color ( < 0.001), but HCW accounted for only ≤2.87% of the variability in ham face L* values and 0.47% of the variability in a* values. Heavier carcasses produced thicker and firmer bellies, with HCW accounting for 37.81% of the variability in belly thickness (β = 0.0272, < 0.001), 20.35% of the variability in subjective flop score (β = 0.0406, < 0.001), and 10.35% of the variability in IV (β = -0.1263, < 0.001). Overall, the proportion of variability in loin and ham quality explained by HCW was poor (≤5.60%), suggesting that HCW is a poor predictor of the primal quality of pigs within this weight range. Nonetheless, HCW was a moderate predictor of belly quality traits. The findings of this study suggest that increasing HCW did not compromise loin, ham, or belly quality attributes.

Variation between hospitals in inpatient admission practices for self-harm patients and its impact on repeat presentation.

PubMed

Carroll, R; Corcoran, P; Griffin, E; Perry, I; Arensman, E; Gunnell, D; Metcalfe, C

2016-11-01

Self-harm patient management varies markedly between hospitals, with fourfold differences in the proportion of patients who are admitted to a medical or psychiatric inpatient bed. The current study aimed to investigate whether differences in admission practices are associated with patient outcomes (repeat self-harm) while accounting for differences in patient case mix. Data came from the National Self-Harm Registry Ireland. A prospective cohort of 43,595 self-harm patients presenting to hospital between 2007 and 2012 were included. As well as conventional regression analysis, instrumental variable (IV) methods utilising between hospital differences in rates of hospital admission were used in an attempt to gain unbiased estimates of the association of admission with risk of repeat self-harm. The proportion of self-harm patients admitted to a medical bed varied from 10 to 74 % between hospitals. Conventional regression and IV analysis suggested medical admission was not associated with risk of repeat self-harm. Psychiatric inpatient admission was associated with an increased risk of repeat self-harm in both conventional and IV analyses. This increased risk persisted in analyses stratified by gender and when restricted to self-poisoning patients only. No strong evidence was found to suggest medical admission reduces the risk of repeat self-harm. Models of health service provision that encourage prompt mental health assessment in the emergency department and avoid unnecessary medical admission of self-harm patients appear warranted. Psychiatric inpatient admission may be associated with a heightened risk of repeat self-harm in some patients, but these findings could be biased by residual confounding and require replication.

Inference for the effect of treatment on survival probability in randomized trials with noncompliance and administrative censoring.

PubMed

Nie, Hui; Cheng, Jing; Small, Dylan S

2011-12-01

In many clinical studies with a survival outcome, administrative censoring occurs when follow-up ends at a prespecified date and many subjects are still alive. An additional complication in some trials is that there is noncompliance with the assigned treatment. For this setting, we study the estimation of the causal effect of treatment on survival probability up to a given time point among those subjects who would comply with the assignment to both treatment and control. We first discuss the standard instrumental variable (IV) method for survival outcomes and parametric maximum likelihood methods, and then develop an efficient plug-in nonparametric empirical maximum likelihood estimation (PNEMLE) approach. The PNEMLE method does not make any assumptions on outcome distributions, and makes use of the mixture structure in the data to gain efficiency over the standard IV method. Theoretical results of the PNEMLE are derived and the method is illustrated by an analysis of data from a breast cancer screening trial. From our limited mortality analysis with administrative censoring times 10 years into the follow-up, we find a significant benefit of screening is present after 4 years (at the 5% level) and this persists at 10 years follow-up. © 2011, The International Biometric Society.

Mortality reductions from marginal increases in public spending on health.

PubMed

Edney, L C; Haji Ali Afzali, H; Cheng, T C; Karnon, J

2018-04-27

There is limited empirical evidence of the nature of any relationship between health spending and health outcomes in Australia. We address this by estimating the elasticity of health outcomes with respect to public healthcare spending using an instrumental variable (IV) approach to account for endogeneity of healthcare spending to health outcomes. Results suggest that, based on the conditional mean, a 1% increase in public health spending was associated with a 2.2% (p < 0.05) reduction in the number of standardised Years of Life Lost (YLL). Sensitivity analyses and robustness checks supported this conclusion. Further exploration using IV quantile regression indicated that marginal returns on public health spending were significantly greater for areas with poorer health outcomes compared to areas with better health outcomes. On average, marginal increases in public health spending reduce YLL, but areas with poorer health outcomes have the greatest potential to benefit from the same marginal increase in public health spending compared to areas with better health outcomes. Understanding the relationship between health spending and outcomes and how this differs according to baseline health outcomes can help meet dual policy objectives to improve the productivity of the healthcare system and reduce inequity. Copyright © 2018 Elsevier B.V. All rights reserved.

The costs of turnover in nursing homes

PubMed Central

Mukamel, Dana B.; Spector, William D.; Limcangco, Rhona; Wang, Ying; Feng, Zhanlian; Mor, Vincent

2009-01-01

Background Turnover rates in nursing homes have been persistently high for decades, ranging upwards of 100%. Objectives To estimate the net costs associated with turnover of direct care staff in nursing homes. Data and sample 902 nursing homes in California in 2005. Data included Medicaid cost reports, the Minimum Data Set (MDS), Medicare enrollment files, Census and Area Resource File (ARF). Research Design We estimated total cost functions, which included in addition to exogenous outputs and wages, the facility turnover rate. Instrumental variable (IV) limited information maximum likelihood techniques were used for estimation to deal with the endogeneity of turnover and costs. Results The cost functions exhibited the expected behavior, with initially increasing and then decreasing returns to scale. The ordinary least square estimate did not show a significant association between costs and turnover. The IV estimate of turnover costs was negative and significant (p=0.039). The marginal cost savings associated with a 10 percentage point increase in turnover for an average facility was $167,063 or 2.9% of annual total costs. Conclusion The net savings associated with turnover offer an explanation for the persistence of this phenomenon over the last decades, despite the many policy initiatives to reduce it. Future policy efforts need to recognize the complex relationship between turnover and costs. PMID:19648834

Thai Undergraduate Chemistry Practical Learning Experiences Using the Jigsaw IV Method

ERIC Educational Resources Information Center

Jansoon, Ninna; Somsook, Ekasith; Coll, Richard K.

2008-01-01

The research reported in this study consisted of an investigation of student learning experiences in Thai chemistry laboratories using the Jigsaw IV method. A hands-on experiment based on the Jigsaw IV method using a real life example based on green tea beverage was designed to improve student affective variables for studying topics related to…

Workshop on Radio Transients

NASA Astrophysics Data System (ADS)

Croft, Steve; Gaensler, Bryan

2012-04-01

abstract-type="normal">SummaryWe are entering a new era in the study of variable and transient radio sources. This workshop discussed the instruments and the strategies employed to study those sources, how they are identified and classified, how results from different surveys can be compared, and how radio observations tie in with those at other wavelengths. The emphasis was on learning what common ground there is between the plethora of on-going projects, how methods and code can be shared, and how best practices regarding survey strategy could be adopted. The workshop featured the four topics below. Each topic commenced with a fairly brief introductory talk, which then developed into discussion. By way of preparation, participants had been invited to upload and discuss one slide per topic to a wiki ahead of the workshop. 1. Telescopes, instrumentation and survey strategy. New radio facilities and on-going projects (including upgrades) are both studying the variability of the radio sky, and searching for transients. The discussion first centred on the status of those facilities, and on projects with a time-domain focus, both ongoing and planned, before turning to factors driving choices of instrumentation, such as phased array versus single pixel feeds, the field of view, spatial and time resolution, frequency and bandwidth, depth, area, and cadence of the surveys. 2. Detection, pipelines, and classification. The workshop debated (a) the factors that influence decisions to study variability in the (u,v) plane, in images, or in catalogues, (b) whether, and how much, pipeline code could potentially be shared between one project and another, and which software packages are best for different approaches, (c) how data are stored and later accessed, and (d) how transients and variables are defined and classified. 3. Statistics, interpretation, and synthesis. It then discussed how (i) the choice of facility and strategy and (ii) detection and classification schemes influence what is seen (in terms of types of object and rates) by different surveys, (iii) how results from different surveys could be compared, and (iv) how what we know from existing surveys drives choices (i) and (ii), particularly as regards finding new classes of object. 4. Multiwavelength approaches. The workshop concluded by discussing what information is needed from wavelengths other than radio in order to classify transients and variables adequately and predict their rates as a function of topics (1), (2) and (3). It asked what the constraints are on responding to, and issuing triggers for, follow-up observations, and how that might feed back into considerations for designing our telescopes and surveys.

Method and Circuit for In-Situ Health Monitoring of Solar Cells in Space

NASA Technical Reports Server (NTRS)

Krasowski, Michael J.; Prokop, Norman F.

2010-01-01

This innovation represents a method and circuit realization of a system designed to make in-situ measurements of test solar-cell operational parameters on orbit using readily available high-temperature and high-ionizing-radiation- tolerant electronic components. This innovation enables on-orbit in-situ solar-array health monitoring and is in response to a need recognized by the U.S. Air Force for future solar arrays for unmanned spacecraft. This system can also be constructed out of commercial-grade electronics and can be embedded into terrestrial solar power system as a diagnostics instrument. This innovation represents a novel approach to I-V curve measurement that is radiation and temperature hard, consumes very few system resources, is economical, and utilizes commercially available components. The circuit will also operate at temperatures as low as 55 C and up to +225 C, allowing it to reside close to the array in direct sunlight. It uses a swept mode transistor functioning as a resistive load while utilizing the solar cells themselves as the biasing device, so the size of the instrument is small and there is no danger of over-driving the cells. Further, this innovation utilizes nearly universal spacecraft bus resources and therefore can be readily adapted to any spacecraft bus allowing for ease of retrofit, or designed into new systems without requiring the addition of infrastructure. One unique characteristic of this innovation is that it effects the measurement of I-V curves without the use of large resistor arrays or active current sources normally used to characterize cells. A single transistor is used as a variable resistive load across the cell. This multi-measurement instrument was constructed using operational amplifiers, analog switches, voltage regulators, MOSFETs, resistors, and capacitors. The operational amplifiers, analog switches, and voltage regulators are silicon-on-insulator (SOI) technology known for its hardness to the effects of ionizing radiation. The SOI components used can tolerate temperatures up to 225 C, which gives plenty of thermal headroom allowing this circuit to perhaps reside in the solar cell panel itself where temperatures can reach over 100 C.

The Evolution of Quasar C IV and Si IV Broad Absorption Lines over Multi-year Timescales

NASA Astrophysics Data System (ADS)

Gibson, Robert R.; Brandt, W. N.; Gallagher, S. C.; Hewett, Paul C.; Schneider, Donald P.

2010-04-01

We investigate the variability of C IV λ1549 broad absorption line (BAL) troughs over rest-frame timescales of up to ≈7 yr in 14 quasars at redshifts z >~ 2.1. For nine sources at sufficiently high redshift, we also compare the C IV and Si IV λ1400 absorption variation. We compare shorter and longer term variability using spectra from up to four different epochs per source and find complex patterns of variation in the sample overall. The scatter in the change of absorption equivalent width (EW), ΔEW, increases with the time between observations. BALs do not, in general, strengthen or weaken monotonically, and variation observed over shorter (lsimmonths) timescales is not predictive of multi-year variation. We find no evidence for asymmetry in the distribution of ΔEW that would indicate that BALs form and decay on different timescales, and we constrain the typical BAL lifetime to be gsim30 yr. The BAL absorption for one source, LBQS 0022+0150, has weakened and may now be classified as a mini-BAL. Another source, 1235+1453, shows evidence of variable, blue continuum emission that is relatively unabsorbed by the BAL outflow. C IV and Si IV BAL shape changes are related in at least some sources. Given their high velocities, BAL outflows apparently traverse large spatial regions and may interact with parsec-scale structures such as an obscuring torus. Assuming BAL outflows are launched from a rotating accretion disk, notable azimuthal symmetry is required in the outflow to explain the relatively small changes observed in velocity structure over times up to 7 yr.

Diagnostic Efficiency among Psychiatric Outpatients of a Self-Report Version of a Subset of Screen Items of the Structured Clinical Interview for DSM-IV-TR Personality Disorders (SCID-II)

ERIC Educational Resources Information Center

Germans, Sara; Van Heck, Guus L.; Masthoff, Erik D.; Trompenaars, Fons J. W. M.; Hodiamont, Paul P. G.

2010-01-01

This article describes the identification of a 10-item set of the Structured Clinical Interview for DSM-IV Personality Disorders (SCID-II) items, which proved to be effective as a self-report assessment instrument in screening personality disorders. The item selection was based on the retrospective analyses of 495 SCID-II interviews. The…

Poliovirus hybrids expressing neutralization epitopes from variable domains I and IV of the major outer membrane protein of Chlamydia trachomatis elicit broadly cross-reactive C. trachomatis-neutralizing antibodies.

PubMed Central

Murdin, A D; Su, H; Klein, M H; Caldwell, H D

1995-01-01

Trachoma and sexually transmitted diseases caused by Chlamydia trachomatis are major health problems worldwide. Epitopes from the variable domains of the major outer membrane protein are candidates for vaccine development. We have constructed hybrid polioviruses expressing sequences from major outer membrane protein variable domains I and IV. Antisera to the hybrids could, in combination, strongly neutralize 8 of the 12 C. trachomatis serovars most commonly associated with oculogenital infections and weakly neutralize the others. PMID:7532625

Maternal employment and the health of low-income young children.

PubMed

Gennetian, Lisa A; Hill, Heather D; London, Andrew S; Lopoo, Leonard M

2010-05-01

This study examines whether maternal employment affects the health status of low-income, elementary-school-aged children using instrumental variables estimation and experimental data from a welfare-to-work program implemented in the early 1990s. Maternal report of child health status is predicted as a function of exogenous variation in maternal employment associated with random assignment to the experimental group. IV estimates show a modest adverse effect of maternal employment on children's health. Making use of data from another welfare-to-work program we propose that any adverse effect on child health may be tempered by increased family income and access to public health insurance coverage, findings with direct relevance to a number of current policy discussions. In a secondary analysis using fixed effects techniques on longitudinal survey data collected in 1998 and 2001, we find a comparable adverse effect of maternal employment on child health that supports the external validity of our primary result.

HIV and sexual behavior change: why not Africa?

PubMed

Oster, Emily

2012-01-01

Despite high rates of HIV in Sub-Saharan Africa, and the corresponding high mortality risk associated with risky sexual behavior, behavioral response has been limited. This paper explores three explanations for this: bias in OLS estimates, limited non-HIV life expectancy and limited knowledge. I find support for the first two. First, using a new instrumental variable strategy I find that OLS estimates of the relationship between risky sex and HIV are biased upwards, and IV estimates indicate reductions in risky behavior in response to the epidemic. Second, I find these reductions are larger for individuals who live in areas with higher life expectancy, suggesting high rates of non-HIV mortality suppress behavioral response; this is consistent with optimizing behavior. Using somewhat limited knowledge proxies, I find no evidence that areas with higher knowledge of the epidemic have greater behavior change. Copyright © 2012 Elsevier B.V. All rights reserved.

Electrophysiologic Study of a Method of Euthanasia Using Intrathecal Lidocaine Hydrochloride Administered during Intravenous Anesthesia in Horses.

PubMed

Aleman, M; Davis, E; Williams, D C; Madigan, J E; Smith, F; Guedes, A

2015-01-01

An intravenous (IV) overdose of pentobarbital sodium is the most commonly used method of euthanasia in veterinary medicine. However, this compound is not available in many countries or rural areas resulting in usage of alternative methods such as intrathecal lidocaine administration after IV anesthesia. Its safety and efficacy as a method of euthanasia have not been investigated in the horse. To investigate changes in mean arterial blood pressure and electrical activity of the cerebral cortex, brainstem, and heart during intrathecal administration of lidocaine. Our hypothesis was that intrathecal lidocaine affects the cerebral cortex and brainstem before affecting cardiovascular function. Eleven horses requiring euthanasia for medical reasons. Prospective observational study. Horses were anesthetized with xylazine, midazolam, and ketamine; and instrumented for recording of electroencephalogram (EEG), electrooculogram (EOG), brainstem auditory evoked response (BAER), and electrocardiogram (ECG). Physical and neurological (brainstem reflexes) variables were monitored. Mean arterial blood pressure was recorded throughout the study. Loss of cerebro-cortical electrical activity occurred up to 226 seconds after the end of the infusion of lidocaine solution. Cessation of brainstem function as evidenced by a lack of brainstem reflexes and disappearance of BAER occurred subsequently. Undetectable heart sounds, nonpalpable arterial pulse, and extremely low mean arterial blood pressure supported cardiac death; a recordable ECG was the last variable to disappear after the infusion (300-1,279 seconds). Intrathecal administration of lidocaine is an effective alternative method of euthanasia in anesthetized horses, during which brain death occurs before cardiac death. Copyright © 2015 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of American College of Veterinary Internal Medicine.

Suicidality in obsessive-compulsive disorder: prevalence and relation to symptom dimensions and comorbid conditions.

PubMed

Torres, Albina R; Ramos-Cerqueira, Ana Teresa A; Ferrão, Ygor A; Fontenelle, Leonardo F; do Rosário, Maria Conceição; Miguel, Euripedes C

2011-01-01

Suicidal thoughts and behaviors, also known as suicidality, are a fairly neglected area of study in patients with obsessive-compulsive disorder (OCD). To evaluate several aspects of suicidality in a large multicenter sample of OCD patients and to compare those with and without suicidal ideation, plans, and attempts according to demographic and clinical variables, including symptom dimensions and comorbid disorders. This cross-sectional study included 582 outpatients with primary OCD (DSM-IV) recruited between August 2003 and March 2008 from 7 centers of the Brazilian Research Consortium on Obsessive-Compulsive Spectrum Disorders. The following assessment instruments were used: the Yale-Brown Obsessive Compulsive Scale, the Dimensional Yale-Brown Obsessive Compulsive Scale, the Beck Depression and Anxiety Inventories, the Structured Clinical Interview for DSM-IV Axis I Disorders, and 6 specific questions to investigate suicidality. After univariate analyses, logistic regression analyses were performed to adjust the associations between the dependent and explanatory variables for possible confounders. Thirty-six percent of the patients reported lifetime suicidal thoughts, 20% had made suicidal plans, 11% had already attempted suicide, and 10% presented current suicidal thoughts. In the logistic regression, only lifetime major depressive disorder and posttraumatic stress disorder (PTSD) remained independently associated with all aspects of suicidal behaviors. The sexual/religious dimension and comorbid substance use disorders remained associated with suicidal thoughts and plans, while impulse-control disorders were associated with current suicidal thoughts and with suicide plans and attempts. The risk of suicidal behaviors must be carefully investigated in OCD patients, particularly those with symptoms of the sexual/religious dimension and comorbid major depressive disorder, PTSD, substance use disorders, and impulse-control disorders. © Copyright 2011 Physicians Postgraduate Press, Inc.

Censored Quantile Instrumental Variable Estimates of the Price Elasticity of Expenditure on Medical Care.

PubMed

Kowalski, Amanda

2016-01-02

Efforts to control medical care costs depend critically on how individuals respond to prices. I estimate the price elasticity of expenditure on medical care using a censored quantile instrumental variable (CQIV) estimator. CQIV allows estimates to vary across the conditional expenditure distribution, relaxes traditional censored model assumptions, and addresses endogeneity with an instrumental variable. My instrumental variable strategy uses a family member's injury to induce variation in an individual's own price. Across the conditional deciles of the expenditure distribution, I find elasticities that vary from -0.76 to -1.49, which are an order of magnitude larger than previous estimates.

Crystal structures of lazulite-type oxidephosphates Ti IIITi IV3O 3(PO 4) 3 and MIII4Ti IV27O 24(PO 4) 24 ( MIII=Ti, Cr, Fe)

NASA Astrophysics Data System (ADS)

Schöneborn, M.; Glaum, R.; Reinauer, F.

2008-06-01

Single crystals of the oxidephosphates Ti IIITi IV3O 3(PO 4) 3 (black), Cr III4Ti IV27O 24(PO 4) 24 (red-brown, transparent), and Fe III4Ti IV27O 24(PO 4) 24 (brown) with edge-lengths up to 0.3 mm were grown by chemical vapour transport. The crystal structures of these orthorhombic members (space group F2 dd ) of the lazulite/lipscombite structure family were refined from single-crystal data [Ti IIITi IV3O 3(PO 4) 3: Z=24, a=7.3261(9) Å, b=22.166(5) Å, c=39.239(8) Å, R1=0.029, w R2=0.084, 6055 independent reflections, 301 variables; Cr III4Ti IV27O 24(PO 4) 24: Z=1, a=7.419(3) Å, b=21.640(5) Å, c=13.057(4) Å, R1=0.037, w R2=0.097, 1524 independent reflections, 111 variables; Fe III4Ti IV27O 24(PO 4) 24: Z=1, a=7.4001(9) Å, b=21.7503(2) Å, c=12.775(3) Å, R1=0.049, w R2=0.140, 1240 independent reflections, 112 variables). For Ti IIITi IVO 3(PO 4) 3 a well-ordered structure built from dimers [Ti III,IV2O 9] and [Ti IV,IV2O 9] and phosphate tetrahedra is found. The metal sites in the crystal structures of Cr 4Ti 27O 24(PO 4) 24 and Fe 4Ti 27O 24(PO 4) 24, consisting of dimers [ MIIITi IVO 9] and [Ti IV,IV2O 9], monomeric [Ti IVO 6] octahedra, and phosphate tetrahedra, are heavily disordered. Site disorder, leading to partial occupancy of all octahedral voids of the parent lipscombite/lazulite structure, as well as splitting of the metal positions is observed. According to Guinier photographs Ti III4Ti IV27O 24(PO 4) 24 ( a=7.418(2) Å, b=21.933(6) Å, c=12.948(7) Å) is isotypic to the oxidephosphates MIII4Ti IV27O 24(PO 4) 24 ( MIII: Cr, Fe). The UV/vis spectrum of Cr 4Ti 27O 24(PO 4) 24 reveals a rather small ligand-field splitting Δ o=14,370 cm -1 and a very low nephelauxetic ratio β=0.72 for the chromophores [Cr IIIO 6] within the dimers [Cr IIITi IVO 9].

49 CFR 572.127 - Test conditions and instrumentation.

Code of Federal Regulations, 2010 CFR

2010-10-01

...) Forces—Class 1000; (ii) Moments—Class 600; (iii) Pendulum acceleration—Class 180; (iv) Rotation—Class 60 (if used). (3) Thorax: (i) Rib acceleration—Class 1000; (ii) Spine and pendulum accelerations—Class...

49 CFR 572.127 - Test conditions and instrumentation.

Code of Federal Regulations, 2014 CFR

2014-10-01

...) Forces—Class 1000; (ii) Moments—Class 600; (iii) Pendulum acceleration—Class 180; (iv) Rotation—Class 60 (if used). (3) Thorax: (i) Rib acceleration—Class 1000; (ii) Spine and pendulum accelerations—Class...

49 CFR 572.127 - Test conditions and instrumentation.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) Forces—Class 1000; (ii) Moments—Class 600; (iii) Pendulum acceleration—Class 180; (iv) Rotation—Class 60 (if used). (3) Thorax: (i) Rib acceleration—Class 1000; (ii) Spine and pendulum accelerations—Class...

49 CFR 572.127 - Test conditions and instrumentation.

Code of Federal Regulations, 2013 CFR

2013-10-01

...) Forces—Class 1000; (ii) Moments—Class 600; (iii) Pendulum acceleration—Class 180; (iv) Rotation—Class 60 (if used). (3) Thorax: (i) Rib acceleration—Class 1000; (ii) Spine and pendulum accelerations—Class...

49 CFR 572.127 - Test conditions and instrumentation.

Code of Federal Regulations, 2012 CFR

2012-10-01

...) Forces—Class 1000; (ii) Moments—Class 600; (iii) Pendulum acceleration—Class 180; (iv) Rotation—Class 60 (if used). (3) Thorax: (i) Rib acceleration—Class 1000; (ii) Spine and pendulum accelerations—Class...

The two variables in the triple system HR 6469 = V819 Her: One eclipsing, one spotted

NASA Technical Reports Server (NTRS)

Van Hamme, Walter V.; Hall, Douglas S.; Hargrove, Adam W.; Henry, Gregory W.; Wasson, Rick; Barksdale, William S.; Chang, Sandy; Fried, Robert E.; Green, Charles L.; Lines, Helen C.

1994-01-01

A complete BV light curve, from 14 nights of good data obtained with the Vanderbilt University-Tennessee State University (VU-TSU) automatic telescope, are presented and solved with the Wilson-Devinney program. Third light is evaluated, with the companion star brighter by 0.58(sup m) in V and 0.11(sup m) in B. The eclipses are partial. Inferred color indices yield F2 V and F8 V for the eclipsing pair and G8 IV-III for the distant companion star. After removing the variability due to eclipses, we study the residual variability of the G8 IV-III star over the ten years 1982 to 1992. Each yearly light curve is fit with a two-spot model. Three relatively long-lived spots are identified, with rotation periods of 85.9(sup d), 85.9(sup d), and 86.1(sup d). The weak and intermittent variability is understood because the G8 IV-III star has a Rossby number at the threshold for the onset of heavy spottedness.

A Conceptual Approach to Assimilating Remote Sensing Data to Improve Soil Moisture Profile Estimates in a Surface Flux/Hydrology Model. Part 1; Overview

NASA Technical Reports Server (NTRS)

Crosson, William L.; Laymon, Charles A.; Inguva, Ramarao; Schamschula, Marius; Caulfield, John

1998-01-01

Knowledge of the amount of water in the soil is of great importance to many earth science disciplines. Soil moisture is a key variable in controlling the exchange of water and energy between the land surface and the atmosphere. Thus, soil moisture information is valuable in a wide range of applications including weather and climate, runoff potential and flood control, early warning of droughts, irrigation, crop yield forecasting, soil erosion, reservoir management, geotechnical engineering, and water quality. Despite the importance of soil moisture information, widespread and continuous measurements of soil moisture are not possible today. Although many earth surface conditions can be measured from satellites, we still cannot adequately measure soil moisture from space. Research in soil moisture remote sensing began in the mid 1970s shortly after the surge in satellite development. Recent advances in remote sensing have shown that soil moisture can be measured, at least qualitatively, by several methods. Quantitative measurements of moisture in the soil surface layer have been most successful using both passive and active microwave remote sensing, although complications arise from surface roughness and vegetation type and density. Early attempts to measure soil moisture from space-borne microwave instruments were hindered by what is now considered sub-optimal wavelengths (shorter than 5 cm) and the coarse spatial resolution of the measurements. L-band frequencies between 1 and 3 GHz (10-30 cm) have been deemed optimal for detection of soil moisture in the upper few centimeters of soil. The Electronically Steered Thinned Array Radiometer (ESTAR), an aircraft-based instrument operating a 1,4 GHz, has shown great promise for soil moisture determination. Initiatives are underway to develop a similar instrument for space. Existing space-borne synthetic aperture radars (SARS) operating at C- and L-band have also shown some potential to detect surface wetness. The advantage of radar is its much higher resolution than passive microwave systems, but it is currently hampered by surface roughness effects and the lack of a good algorithm based on a single frequency and single polarization. In addition, its repeat frequency is generally low (about 40 days). In the meantime, two new radiometers offer some hope for remote sensing of soil moisture from space. The Tropical Rainfall Measuring Mission (TRMM) Microwave Imager (TMI), launched in November 1997, possesses a 10.65 GHz channel and the Advanced Microwave Scanning Radiometer (AMSR) on both the ADEOS-11 and Earth Observing System AM-1 platforms to be launched in 1999 possesses a 6.9 GHz channel. Aside from issues about interference from vegetation, the coarse resolution of these data will provide considerable challenges pertaining to their application. The resolution of TMI is about 45 km and that of AMSR is about 70 km. These resolutions are grossly inconsistent with the scale of soil moisture processes and the spatial variability of factors that control soil moisture. Scale disparities such as these are forcing us to rethink how we assimilate data of various scales in hydrologic models. Of particular interest is how to assimilate soil moisture data by reconciling the scale disparity between what we can expect from present and future remote sensing measurements of soil moisture and modeling soil moisture processes. It is because of this disparity between the resolution of space-based sensors and the scale of data needed for capturing the spatial variability of soil moisture and related properties that remote sensing of soil moisture has not met with more widespread success. Within a single footprint of current sensors at the wavelengths optimal for this application, in most cases there is enormous heterogeneity in soil moisture created by differences in landcover, soils and topography, as well as variability in antecedent precipitation. It is difficult to interpret the meaning of 'mean' soil moisture under such conditions and even more difficult to apply such a value. Because of the non-linear relationships between near-surface soil moisture and other variables of interest, such as surface energy fluxes and runoff, mean soil moisture has little applicability at such large scales. It is for these reasons that the use of remote sensing in conjunction with a hydrologic model appears to be of benefit in capturing the complete spatial and temporal structure of soil moisture. This paper is Part I of a four-part series describing a method for intermittently assimilating remotely-sensed soil moisture information to improve performance of a distributed land surface hydrology model. The method, summarized in section II, involves the following components, each of which is detailed in the indicated section of the paper or subsequent papers in this series: Forward radiative transfer model methods (section II and Part IV); Use of a Kalman filter to assimilate remotely-sensed soil moisture estimates with the model profile (section II and Part IV); Application of a soil hydrology model to capture the continuous evolution of the soil moisture profile within and below the root zone (section III); Statistical aggregation techniques (section IV and Part II); Disaggregation techniques using a neural network approach (section IV and Part III); and Maximum likelihood and Bayesian algorithms for inversely solving for the soil moisture profile in the upper few cm (Part IV).

A global database with parallel measurements to study non-climatic changes

NASA Astrophysics Data System (ADS)

Venema, Victor; Auchman, Renate; Aguilar, Enric

2017-04-01

In this work we introduce the rationale behind the ongoing compilation of a parallel measurements database, in the framework of the International Surface Temperatures Initiative (ISTI) and with the support of the World Meteorological Organization. We intend this database to become instrumental for a better understanding of inhomogeneities affecting the evaluation of long-term changes in daily climate data. Long instrumental climate records are usually affected by non-climatic changes, due to, e.g., (i) station re- locations, (ii) instrument height changes, (iii) instrumentation changes, (iv) observing environment changes, (v) different sampling intervals or data collection procedures, among others. These so-called inhomogeneities distort the climate signal and can hamper the assessment of long-term trends and variability of climate. Thus to study climatic changes we need to accurately distinguish non-climatic and climatic signals. The most direct way to study the influence of non-climatic changes on the distribution and to understand the reasons for these biases is the analysis of parallel measurements representing the old and new situation (in terms of e.g. instruments, location, different radiation shields, etc.). According to the limited number of available studies and our understanding of the causes of inhomogeneity, we expect that they will have a strong impact on the tails of the distribution of air temperatures and most likely of other climate elements. Our abilities to statistically homogenize daily data will be increased by systematically studying different causes of inhomogeneity replicated through parallel measurements. Current studies of non-climatic changes using parallel data are limited to local and regional case studies. However, the effect of specific transitions depends on the local climate and the most interesting climatic questions are about the systematic large-scale biases produced by transitions that occurred in many regions. Important potentially biasing transitions are the adoption of Stevenson screens, relocations (to airports) efforts to reduce undercatchment of precipitation or the move to automatic weather stations. Thus a large global parallel dataset is highly desirable as it allows for the study of systematic biases in the global record. We are interested in data from all climate variables at all time scales; from annual to sub-daily. High-resolution data is important for understanding the physical causes for the differences between the parallel measurements. For the same reason, we are also interested in other climate variables measured at the same station. For example, in case of parallel air temperature measurements, the influencing factors are expected to be global radiation, wind, humidity and cloud cover; in case of parallel precipitation measurements, wind and wet-bulb temperature are potentially important.

49 CFR 572.146 - Test conditions and instrumentation.

Code of Federal Regulations, 2013 CFR

2013-10-01

...) Head acceleration—Class 1000 (2) Neck (i) Force—Class 1000 (ii) Moments—Class 600 (iii) Pendulum... acceleration—Class 1000 (ii) Spine and pendulum accelerations—Class 180 (iii) Sternum deflection—Class 600 (iv...

49 CFR 572.155 - Test conditions and instrumentation.

Code of Federal Regulations, 2014 CFR

2014-10-01

...) Moments—Class 600; (iii) Pendulum acceleration—Class 180; (iv) Rotation potentiometer response (if used)—CFC 60. (3) Thorax: (i) Spine and pendulum accelerations—Class 180; (ii) Shoulder forces—Class 600; (4...

49 CFR 572.155 - Test conditions and instrumentation.

Code of Federal Regulations, 2013 CFR

2013-10-01

...) Moments—Class 600; (iii) Pendulum acceleration—Class 180; (iv) Rotation potentiometer response (if used)—CFC 60. (3) Thorax: (i) Spine and pendulum accelerations—Class 180; (ii) Shoulder forces—Class 600; (4...

49 CFR 572.155 - Test conditions and instrumentation.

Code of Federal Regulations, 2012 CFR

2012-10-01

...) Moments—Class 600; (iii) Pendulum acceleration—Class 180; (iv) Rotation potentiometer response (if used)—CFC 60. (3) Thorax: (i) Spine and pendulum accelerations—Class 180; (ii) Shoulder forces—Class 600; (4...

49 CFR 572.146 - Test conditions and instrumentation.

Code of Federal Regulations, 2012 CFR

2012-10-01

...) Head acceleration—Class 1000 (2) Neck (i) Force—Class 1000 (ii) Moments—Class 600 (iii) Pendulum... acceleration—Class 1000 (ii) Spine and pendulum accelerations—Class 180 (iii) Sternum deflection—Class 600 (iv...

49 CFR 572.146 - Test conditions and instrumentation.

Code of Federal Regulations, 2014 CFR

2014-10-01

...) Head acceleration—Class 1000 (2) Neck (i) Force—Class 1000 (ii) Moments—Class 600 (iii) Pendulum... acceleration—Class 1000 (ii) Spine and pendulum accelerations—Class 180 (iii) Sternum deflection—Class 600 (iv...

49 CFR 572.155 - Test conditions and instrumentation.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) Moments—Class 600; (iii) Pendulum acceleration—Class 180; (iv) Rotation potentiometer response (if used)—CFC 60. (3) Thorax: (i) Spine and pendulum accelerations—Class 180; (ii) Shoulder forces—Class 600; (4...

49 CFR 572.146 - Test conditions and instrumentation.

Code of Federal Regulations, 2010 CFR

2010-10-01

...) Head acceleration—Class 1000 (2) Neck (i) Force—Class 1000 (ii) Moments—Class 600 (iii) Pendulum... acceleration—Class 1000 (ii) Spine and pendulum accelerations—Class 180 (iii) Sternum deflection—Class 600 (iv...

49 CFR 572.146 - Test conditions and instrumentation.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) Head acceleration—Class 1000 (2) Neck (i) Force—Class 1000 (ii) Moments—Class 600 (iii) Pendulum... acceleration—Class 1000 (ii) Spine and pendulum accelerations—Class 180 (iii) Sternum deflection—Class 600 (iv...

49 CFR 572.155 - Test conditions and instrumentation.

Code of Federal Regulations, 2010 CFR

2010-10-01

...) Moments—Class 600; (iii) Pendulum acceleration—Class 180; (iv) Rotation potentiometer response (if used)—CFC 60. (3) Thorax: (i) Spine and pendulum accelerations—Class 180; (ii) Shoulder forces—Class 600; (4...

Airborne gas chromatograph for in situ measurements of long-lived species in the upper troposphere and lower stratosphere

NASA Astrophysics Data System (ADS)

Elkins, J. W.; Fahey, D. W.; Gilligan, J. M.; Dutton, G. S.; Baring, T. J.; Volk, C. M.; Dunn, R. E.; Myers, R. C.; Montzka, S. A.; Wamsley, P. R.; Hayden, A. H.; Butler, J. H.; Thompson, T. M.; Swanson, T. H.; Dlugokencky, E. J.; Novelli, P. C.; Hurst, D. F.; Lobert, J. M.; Ciciora, S. J.; McLaughlin, R. J.; Thompson, T. L.; Winkler, R. H.; Fraser, P. J.; Steele, L. P.; Lucarelli, M. P.

A new instrument, the Airborne Chromatograph for Atmospheric Trace Species IV (ACATS-IV), for measuring long-lived species in the upper troposphere and lower stratosphere is described. Using an advanced approach to gas chromatography and electron capture detection, the instrument can detect low levels of CFC-11 (CCl3F), CFC-12 (CCl2F2), CFC-113 (CCl2F-CClF2), methyl chloroform (CH3CCl3), carbon tetrachloride (CCl4), nitrous oxide (N2O), sulfur hexafluoride (SF6), Halon-1211 (CBrClF2), hydrogen (H2), and methane (CH4) acquired in ambient samples every 180 or 360 s. The instrument operates fully-automated onboard the NASA ER-2 high-altitude aircraft on flights lasting up to 8 hours or more in duration. Recent measurements include 24 successful flights covering a broad latitude range (70°S-61°N) during the Airborne Southern Hemisphere Ozone Experiment/Measurements for Assessing the Effects of Stratospheric Aircraft (ASHOE/MAESA) campaign in 1994.

Intravenous cannulation of adolescents does not affect the modulation of autonomic tone assessed by heart rate and blood pressure variability.

PubMed

Stewart, J M

2000-02-01

Invasive arterial monitoring alters autonomic tone. The effects of intravenous (i.v.) insertion are less clear. The author assessed the effects of i.v. insertion on autonomic activity in patients aged 11 to 19 years prior to head-up tilt by measuring heart rate, blood pressure, heart rate variability, blood pressure variability, and baroreceptor gain before and after i.v. insertion with continuous electrocardiography and arterial tonometry in patients with orthostatic tachycardia syndrome (OTS, N = 21), in patients who experienced simple fainting (N = 14), and in normal control subjects (N = 6). Five-minute samples were collected after 30 minutes supine. Fifteen minutes after i.v. insertion, data were collected again. These 5-minute samples were also collected in a separate control population without i.v. insertion after 30 minutes supine and again 30 minutes later. This population included 12 patients with OTS, 13 patients who experienced simple fainting, and 6 normal control subjects. Heart rate variability included the mean RR, the standard deviation of the RR interval (SDNN), and the root mean square of successive RR differences (RMSSD). Autoregressive spectral modeling was used. Low-frequency power (LFP, 0.04-0.15 Hz), high-frequency power (HFP, 0.15-0.40 Hz), and total power (TP, 0.01-0.40 Hz) were compared. Blood pressure variability included standard deviation of systolic blood pressure, LFP, and HFP. Baroreceptor gain at low frequency and high frequency was calculated from cross-spectral transfer function magnitudes when coherence was greater than 0.5. In patients with OTS, RR (790 +/- 50 msec), SDNN (54 +/- 6 msec), RMSSD (55 +/- 5 msec), LFP (422 +/- 200 ms2/Hz), HFP (846 +/- 400 ms2/Hz), and TP (1550 +/- 320 ms2/Hz) were less than in patients who experienced simple fainting (RR, 940 +/- 50 msec; SDNN, 84 +/- 10 msec; RMSSD, 91 +/- 7 msec; LFP, 880 +/- 342 ms2/Hz; HFP, 1720 +/- 210 ms2/Hz; and TP, 3228 +/- 490 ms2/Hz) or normal control subjects (RR, 920 +/- 30 msec; SDNN, 110 +/- 29 msec; RMSSD, 120 +/- 16 msec; LFP, 1600 +/- 331 ms2/Hz; HFP, 2700 +/- 526 ms2/Hz; and TP, 5400 +/- 1017 ms2/Hz). Blood pressure and blood pressure variability were not different in any group. Standard deviation, LFP, and HFP were, respectively, 5.24 +/- 0.8 mm Hg, 1.2 +/- 0.2, and 1.5 +/- 0.3 for patients with OTS; 4.6 +/- 0.4 mm Hg, 1.2 +/- 0.2, and 1.4 +/- 0.3 for patients who experienced simple fainting; and 5.55 +/- 1.0 mm Hg, 1.4 +/- 0.2, and 1.6 +/- 0.3 for normal control subjects. Baroreceptor gain at low frequency and high frequency in patients with OTS (16 +/- 4 msec/mm Hg, 17 +/- 5) was comparable to that in patients who experienced simple fainting (33 +/- 4, 32 +/- 3) and that in normal control subjects (31 +/- 8, 37 +/- 9). Heart rate variability differed between patients with OTS and patients who experienced simple fainting or normal control subjects, and blood pressure and blood pressure variability were not different, but no parameter changed after i.v. insertion. There were no differences from the groups that did not receive i.v. insertions. Data suggest, at most, a limited effect of i.v. insertion on autonomic function in adolescents.

[Patients' perspective and economic variables as objectives in clinical trials: added value to clinical parameters].

PubMed

Bovaira-García, M J; Soler-Company, E

2012-01-01

Patient-reported outcome (PRO) measures complement traditional biomedical outcome measures. The purpose of this study was to evaluate the use of PRO measures including health-related quality of life (HRQoL) questionnaires as a measurement of efficacy and the frequency of inclusion of economic variables related to direct and indirect costs in the design of clinical trials and phase IV observational studies. Moreover, for the trials quality score were measured, and if there were any relationship between the quality study design score and the PRO inclusion. Retrospective observational study of the clinical trials and phase IV observational studies approved by a Clinical Research Ethics Committee (2008-2010). We gathered data concerning general aspects including medical specialty, pathology, methodological quality based on Jadad scale (0-5), inclusion of PRO and economic variables. For clinical trials including HRQoL measurements, we analysed the type of questionnaire in use. Where there were no HRQoL measurements, we analysed if their inclusion would have been proper or not. A total of 70 protocols (59 CTs and 11 phase IV observational studies) were analysed; 37 (52.8%) included PRO measures, and 3 protocols (4.3%) used them as a primary endpoint. Data analysis by therapeutic area showed that PRO measures were most commonly studied in the fields of endocrinology, neurology, digestive diseases, and cardiology. The average quality score for the trials was 2.8. The trials with more PRO inclusion in their end points had a significantly higher quality score. Only 13 (22%) clinical trials and 2 (18.2%) phase IV observational studies included economic variables. The emergence of economic variables in clinical trials and phase IV observational studies evaluated was low, however, more than half of the revised protocols have included PRO measures, reflecting the importance of these parameters in the assessment of the effectiveness of drug treatments, although its use is still not systematic. Copyright © 2011 SECA. Published by Elsevier Espana. All rights reserved.

Screening older cancer patients for a Comprehensive Geriatric Assessment: A comparison of three instruments

PubMed Central

Owusu, Cynthia; Koroukian, Siran M.; Schluchter, Mark; Bakaki, Paul; Berger, Nathan A.

2011-01-01

Background The Vulnerable Elders Survey (VES-13) has been validated for screening older cancer patients for a Comprehensive Geriatric Assessment (CGA). To identify a widely acceptable approach that encourages oncologists to screen older cancer patients for a CGA, we examined the Eastern Cooperative Oncology Group Performance Status (ECOG-PS) and Karnofsky Index of Performance Status (KPS) scales’ ability to identify abnormalities on a CGA and compared the performance of the two instruments with the VES-13. Methods We enrolled 117 participants, ≥65 years with stage I–IV cancer into this cross-sectional study. Our primary outcome variable was ≥two abnormalities on the CGA, (Yes or No). We employed receiver operating characteristic curve analysis to compare the discriminatory abilities of the three instruments to identify ≥two abnormalities on the CGA. Results Of the 117 participants, 43% had ≥two abnormalities on the CGA. The VES-13 was predictive of ≥two abnormalities on the CGA, area under the curve (AUC)=0.85 [(95% CI: 0.78–0.92); sensitivity=88%, specificity=69%, at cut-off ≥3]. The ECOG-PS and KPS showed similar discriminatory powers, AUC=0.88 [(95% CI: 0.83–0.94); sensitivity=94%, specificity=55%, at cut-off ≥1]; and AUC=0.90 [(95% CI: 0.84–0.96); sensitivity=78%, specificity=91%, at cut-off ≤80%], respectively. Conclusion The ECOG-PS and KPS were equivalent to the VES-13 in identifying older cancer patients with at least two abnormalities on the CGA. Given that oncologists are already conversant with the KPS and ECOG-PS, these two instruments offer medical oncologists a widely acceptable approach for screening older patients for a CGA. PMID:21927633

Censored Quantile Instrumental Variable Estimates of the Price Elasticity of Expenditure on Medical Care

PubMed Central

Kowalski, Amanda

2015-01-01

Efforts to control medical care costs depend critically on how individuals respond to prices. I estimate the price elasticity of expenditure on medical care using a censored quantile instrumental variable (CQIV) estimator. CQIV allows estimates to vary across the conditional expenditure distribution, relaxes traditional censored model assumptions, and addresses endogeneity with an instrumental variable. My instrumental variable strategy uses a family member’s injury to induce variation in an individual’s own price. Across the conditional deciles of the expenditure distribution, I find elasticities that vary from −0.76 to −1.49, which are an order of magnitude larger than previous estimates. PMID:26977117

Influence of cognition and symptoms of schizophrenia on IADL performance.

PubMed

Lipskaya, Lena; Jarus, Tal; Kotler, Moshe

2011-09-01

People with schizophrenia experience difficulties with instrumental activities of daily living (IADL), which are required for independent living. Yet, factors that influence IADL performance are still poorly understood. Identification of such factors will contribute to the rehabilitation process and recovery. The present study aimed to examine the influence of cognitive abilities, schizophrenia symptoms, and demographic variables on IADL functioning during acute hospital admission. The participants were 81 adults with DSM-IV chronic schizophrenia. They were assessed on the Revised Observed Tasks of Daily Living (OTDL-R), the Positive and Negative Syndrome Scale (PANSS), the Neurobehavioral Cognitive Status Examination (Cognistat), and the Kitchen Task Assessment (KTA) at acute hospitalization. The prediction model of IADL performance at this time consists of executive functioning (explained 21% of variance), memory and abstract thinking (explained 13.5%), negative symptoms (explained 13%), age of illness onset and years of education (explained 8%). The total explained variance is 53.5%. These results provide evidence-based guidelines for the evaluation process in inpatient settings. Such guidelines are important since planning of intervention processes and appropriate community integration programs often occurs during acute hospitalization, while the structured nature of inpatient settings limits natural variability in occupational performance.

Physicians' prescribing preferences were a potential instrument for patients' actual prescriptions of antidepressants☆

PubMed Central

Davies, Neil M.; Gunnell, David; Thomas, Kyla H.; Metcalfe, Chris; Windmeijer, Frank; Martin, Richard M.

2013-01-01

Objectives To investigate whether physicians' prescribing preferences were valid instrumental variables for the antidepressant prescriptions they issued to their patients. Study Design and Setting We investigated whether physicians' previous prescriptions of (1) tricyclic antidepressants (TCAs) vs. selective serotonin reuptake inhibitors (SSRIs) and (2) paroxetine vs. other SSRIs were valid instruments. We investigated whether the instrumental variable assumptions are likely to hold and whether TCAs (vs. SSRIs) were associated with hospital admission for self-harm or death by suicide using both conventional and instrumental variable regressions. The setting for the study was general practices in the United Kingdom. Results Prior prescriptions were strongly associated with actual prescriptions: physicians who previously prescribed TCAs were 14.9 percentage points (95% confidence interval [CI], 14.4, 15.4) more likely to prescribe TCAs, and those who previously prescribed paroxetine were 27.7 percentage points (95% CI, 26.7, 28.8) more likely to prescribe paroxetine, to their next patient. Physicians' previous prescriptions were less strongly associated with patients' baseline characteristics than actual prescriptions. We found no evidence that the estimated association of TCAs with self-harm/suicide using instrumental variable regression differed from conventional regression estimates (P-value = 0.45). Conclusion The main instrumental variable assumptions held, suggesting that physicians' prescribing preferences are valid instruments for evaluating the short-term effects of antidepressants. PMID:24075596

OSO 8 observations of wave propagation in the solar chromosphere and transition region

NASA Technical Reports Server (NTRS)

Chipman, E. G.

1978-01-01

The University of Colorado instrument on OSO 8 has been used to observe relative phases of the 300-s intensity variation between the temperature-minimum region and several emission lines formed in the solar chromosphere and chromosphere-corona transition region. The lines used are due to Fe II, Si II, C II, Si IV, and C IV. The scattered light in the spectrograph, which originates almost entirely in the spectral region between 1700 and 1900 A, was used as a probe of the temperature-minimum region. The lines of Fe II, Si II, and C II show almost identical delays of approximately 30 s relative to the temperature minimum, while the intensity oscillations of the lines of Si IV and C IV appear to lead the temperature-minimum intensity oscillations by about 10 s.

UV - GAITHERSBURG MD

EPA Science Inventory

Brewer 105 is located in Gaithersburg MD, measuring ultraviolet solar radiation. Irradiance and column ozone are derived from this data. Ultraviolet solar radiation is measured with a Brewer Mark IV, single-monochrometer, spectrophotometer manufactured by SCI-TEC Instruments, Inc...

Can Women Have Children and a Career? IV Evidence from IVF Treatments.

PubMed

Lundborg, Petter; Plug, Erik; Rasmussen, Astrid Wurtz

2017-06-01

This paper introduces a new IV strategy based on IVF (in vitro fertilization) induced fertility variation among childless women to estimate the causal effect of having children on their career. For this purpose, we use administrative data on IVF treated women in Denmark. Because observed chances of IVF success do not depend on labor market histories, IVF treatment success provides a plausible instrument for childbearing. Our IV estimates indicate that fertility effects on earnings are: (i) negative, large, and long-lasting; (ii) driven by fertility effects on hourly earnings and not so much on labor supply; and (iii) much stronger at the extensive margin than at the intensive margin.

Instrumental Variable Analysis with a Nonlinear Exposure–Outcome Relationship

PubMed Central

Davies, Neil M.; Thompson, Simon G.

2014-01-01

Background: Instrumental variable methods can estimate the causal effect of an exposure on an outcome using observational data. Many instrumental variable methods assume that the exposure–outcome relation is linear, but in practice this assumption is often in doubt, or perhaps the shape of the relation is a target for investigation. We investigate this issue in the context of Mendelian randomization, the use of genetic variants as instrumental variables. Methods: Using simulations, we demonstrate the performance of a simple linear instrumental variable method when the true shape of the exposure–outcome relation is not linear. We also present a novel method for estimating the effect of the exposure on the outcome within strata of the exposure distribution. This enables the estimation of localized average causal effects within quantile groups of the exposure or as a continuous function of the exposure using a sliding window approach. Results: Our simulations suggest that linear instrumental variable estimates approximate a population-averaged causal effect. This is the average difference in the outcome if the exposure for every individual in the population is increased by a fixed amount. Estimates of localized average causal effects reveal the shape of the exposure–outcome relation for a variety of models. These methods are used to investigate the relations between body mass index and a range of cardiovascular risk factors. Conclusions: Nonlinear exposure–outcome relations should not be a barrier to instrumental variable analyses. When the exposure–outcome relation is not linear, either a population-averaged causal effect or the shape of the exposure–outcome relation can be estimated. PMID:25166881

Neighborhood Prices of Healthier and Unhealthier Foods and Associations with Diet Quality: Evidence from the Multi-Ethnic Study of Atherosclerosis.

PubMed

Kern, David M; Auchincloss, Amy H; Stehr, Mark F; Roux, Ana V Diez; Moore, Latetia V; Kanter, Genevieve P; Robinson, Lucy F

2017-11-16

It is known that the price of food influences the purchasing and consumption decisions of individuals; however, little work has examined if the price of healthier food relative to unhealthier food in an individual's neighborhood is associated with overall dietary quality while using data from multiple regions in the United States. Cross-sectional person-level data came from The Multi-Ethnic Study of Atherosclerosis (exam 5, 2010-2012 n = 2765); a food frequency questionnaire assessed diet. Supermarket food/beverage prices came from Information Resources Inc. (n = 794 supermarkets). For each individual, the average price of select indicators of healthier foods (vegetables, fruits, dairy) and unhealthier foods (soda, sweets, salty snacks), as well as their ratio, was computed for supermarkets within three miles of the person's residential address. Logistic regression estimated odds ratios of a high-quality diet (top quintile of Healthy Eating Index 2010) associated with healthy-to-unhealthy price ratio, adjusted for individual and neighborhood characteristics. Sensitivity analyses used an instrumental variable (IV) approach. Healthier foods cost nearly twice as much as unhealthier foods per serving on average (mean healthy-to-unhealthy ratio = 1.97 [SD 0.14]). A larger healthy-to-unhealthy price ratio was associated with lower odds of a high-quality diet (OR = 0.76 per SD increase in the ratio, 95% CI = [0.64-0.9]). IV analyses largely confirmed these findings although-as expected with IV adjustment-confidence intervals were wide (OR = 0.82 [0.57-1.19]). Policies to address the large price differences between healthier and unhealthy foods may help improve diet quality in the United States.

Neighborhood Prices of Healthier and Unhealthier Foods and Associations with Diet Quality: Evidence from the Multi-Ethnic Study of Atherosclerosis

PubMed Central

Kern, David M.; Stehr, Mark F.; Diez Roux, Ana V.; Moore, Latetia V.; Kanter, Genevieve P.; Robinson, Lucy F.

2017-01-01

It is known that the price of food influences the purchasing and consumption decisions of individuals; however, little work has examined if the price of healthier food relative to unhealthier food in an individual’s neighborhood is associated with overall dietary quality while using data from multiple regions in the United States. Cross-sectional person-level data came from The Multi-Ethnic Study of Atherosclerosis (exam 5, 2010–2012, n = 2765); a food frequency questionnaire assessed diet. Supermarket food/beverage prices came from Information Resources Inc. (n = 794 supermarkets). For each individual, the average price of select indicators of healthier foods (vegetables, fruits, dairy) and unhealthier foods (soda, sweets, salty snacks), as well as their ratio, was computed for supermarkets within three miles of the person’s residential address. Logistic regression estimated odds ratios of a high-quality diet (top quintile of Healthy Eating Index 2010) associated with healthy-to-unhealthy price ratio, adjusted for individual and neighborhood characteristics. Sensitivity analyses used an instrumental variable (IV) approach. Healthier foods cost nearly twice as much as unhealthier foods per serving on average (mean healthy-to-unhealthy ratio = 1.97 [SD 0.14]). A larger healthy-to-unhealthy price ratio was associated with lower odds of a high-quality diet (OR = 0.76 per SD increase in the ratio, 95% CI = [0.64–0.9]). IV analyses largely confirmed these findings although—as expected with IV adjustment—confidence intervals were wide (OR = 0.82 [0.57–1.19]). Policies to address the large price differences between healthier and unhealthy foods may help improve diet quality in the United States. PMID:29144387

Public transport policy, social engagement and mental health in older age: a quasi-experimental evaluation of free bus passes in England.

PubMed

Reinhard, Erica; Courtin, Emilie; van Lenthe, Frank J; Avendano, Mauricio

2018-05-01

Social engagement and social isolation are key determinants of mental health in older age, yet there is limited evidence on how public policies may contribute to reducing isolation, promoting social engagement and improving mental health among older people. This study examines the impact of the introduction of an age-friendly transportation policy, free bus passes, on the mental health of older people in England. We use an instrumental variable (IV) approach that exploits eligibility criteria for free bus passes to estimate the impact of increased public transportation use on depressive symptoms, loneliness, social isolation and social engagement. Eligibility for the free bus travel pass was associated with an 8% (95% CI 6.4% to 9.6%) increase in the use of public transportation among older people. The IV model suggests that using public transport reduces depressive symptoms by 0.952 points (95% CI -1.712 to -0.192) on the Center for Epidemiologic Studies Depression Scale. IV models also suggest that using public transport reduces feelings of loneliness (β -0.794, 95% CI -1.528 to -0.061), increases volunteering at least monthly (β 0.237, 95% CI 0.059 to 0.414) and increases having regular contact with children (β 0.480, 95% CI 0.208 to 0.752) and friends (β 0.311, 95% CI 0.109 to 0.513). Free bus travel is associated with reductions in depressive symptoms and feelings of loneliness among older people. Transportation policies may increase older people's social engagement and consequently deliver significant benefits to mental health. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Hardware and software systems for the determination of charged particle parameters in low pressure plasmas using impedance-tuned Langmuir probes

NASA Astrophysics Data System (ADS)

Ye, Yuancai; Marcus, R. Kenneth

1997-12-01

A computer-controlled, impedance-tuned Langmuir probe data acquisition system and processing software package have been designed for the diagnostic study of low pressure plasmas. The combination of impedance-tuning and a wide range of applied potentials (± 100 V) provides a versatile system, applicable to a variety of analytical plasmas without significant modification. The automated probe system can be used to produce complete and undistorted current-voltage (i-V) curves with extremely low noise over the wide potential range. Based on these hardware and software systems, it is possible to determine all of the important charged particle parameters in a plasma; electron number density ( ne), ion number density ( ni), electron temperature ( Te), electron energy distribution function (EEDF), and average electron energy (<ɛ>). The complete data acquisition system and evaluation software are described in detail. A LabView (National Instruments Corporation, Austin, TX) application program has been developed for the Apple Macintosh line of microcomputers to control all of the operational aspects of the Langmuir probe experiments. The description here is mainly focused on the design aspects of the acquisition system with the targets of extremely low noise and reduction of the influence of measurement noise in the calculation procedures. This is particularly important in the case of electron energy distribution functions where multiple derivatives are calculated from the obtained i-V curves. A separate C-language data processing program has been developed and is included here to allow the reader to evaluate data obtained with the described hardware, or any i-V data imported in tab separated variable format. Both of the software systems are included on a Macintosh formatted disk for their use in other laboratories desiring these capabilities.

Evaluation and validation of social and psychological markers in randomised trials of complex interventions in mental health: a methodological research programme.

PubMed

Dunn, Graham; Emsley, Richard; Liu, Hanhua; Landau, Sabine; Green, Jonathan; White, Ian; Pickles, Andrew

2015-11-01

The development of the capability and capacity to evaluate the outcomes of trials of complex interventions is a key priority of the National Institute for Health Research (NIHR) and the Medical Research Council (MRC). The evaluation of complex treatment programmes for mental illness (e.g. cognitive-behavioural therapy for depression or psychosis) not only is a vital component of this research in its own right but also provides a well-established model for the evaluation of complex interventions in other clinical areas. In the context of efficacy and mechanism evaluation (EME) there is a particular need for robust methods for making valid causal inference in explanatory analyses of the mechanisms of treatment-induced change in clinical outcomes in randomised clinical trials. The key objective was to produce statistical methods to enable trial investigators to make valid causal inferences about the mechanisms of treatment-induced change in these clinical outcomes. The primary objective of this report is to disseminate this methodology, aiming specifically at trial practitioners. The three components of the research were (1) the extension of instrumental variable (IV) methods to latent growth curve models and growth mixture models for repeated-measures data; (2) the development of designs and regression methods for parallel trials; and (3) the evaluation of the sensitivity/robustness of findings to the assumptions necessary for model identifiability. We illustrate our methods with applications from psychological and psychosocial intervention trials, keeping the technical details to a minimum, leaving the reporting of the more theoretical and mathematically demanding results for publication in appropriate specialist journals. We show how to estimate treatment effects and introduce methods for EME. We explain the use of IV methods and principal stratification to evaluate the role of putative treatment effect mediators and therapeutic process measures. These results are extended to the analysis of longitudinal data structures. We consider the design of EME trials. We focus on designs to create convincing IVs, bearing in mind assumptions needed to attain model identifiability. A key area of application that has become apparent during this work is the potential role of treatment moderators (predictive markers) in the evaluation of treatment effect mechanisms for personalised therapies (stratified medicine). We consider the role of targeted therapies and multiarm trials and the use of parallel trials to help elucidate the evaluation of mediators working in parallel. In order to demonstrate both efficacy and mechanism, it is necessary to (1) demonstrate a treatment effect on the primary (clinical) outcome, (2) demonstrate a treatment effect on the putative mediator (mechanism) and (3) demonstrate a causal effect from the mediator to the outcome. Appropriate regression models should be applied for (3) or alternative IV procedures, which account for unmeasured confounding, provided that a valid instrument can be identified. Stratified medicine may provide a setting where such instruments can be designed into the trial. This work could be extended by considering improved trial designs, sample size considerations and measurement properties. The project presents independent research funded under the MRC-NIHR Methodology Research Programme (grant reference G0900678).

A new instrument to measure pre-service primary teachers' attitudes to teaching mathematics

NASA Astrophysics Data System (ADS)

Nisbet, Steven

1991-06-01

This article outlines the development of an instrument to measure pre-service primary teachers' attitudes to teaching mathematics. A trial questionnaire was devised using the set of Fennema-Sherman scales on students' attitudes to the subject mathematics as a model. Analysis of the responses to the questionnaire by 155 student teachers was carried out to develop meaningful attitude scales and to refine the instrument. The end-product is a new instrument which can be used to monitor the attitudes of student teachers. The attitude scales identified in the analysis and built into the final form of the questionnaire are (i) anxiety, (ii) confidence and enjoyment, (iii) desire for recognition and (iv) pressure to conform.

Ultraviolet continuum absorption /less than about 1000 A/ above the quiet sun transition region

NASA Technical Reports Server (NTRS)

Doschek, G. A.; Feldman, U.

1982-01-01

Lyman continuum absorption shortward of 912 A in the quiet sun solar transition region is investigated by combining spectra obtained from the Apollo Telescope Mount experiments on Skylab. The most recent atomic data are used to compute line intensities for lines that fall on both sides of the Lyman limit. Lines of O III, O IV, O V, and S IV are considered. The computed intensity ratios of most lines from O IV, O V, and S IV agree with the experimental ratios to within a factor of 2. However, the discrepancies show no apparent wavelength dependence. From this fact, it is concluded that at least part of the discrepancy between theory and observation for lines of these ions can be accounted for by uncertainties in instrumental calibration and atomic data. However, difficulties remain in reconciling observation and theory, particularly for lines of O III, and one line of S IV. The other recent results of Schmahl and Orrall (1979) are also discussed in terms of newer atomic data.

Angiotensin II and CRF receptors in the central nucleus of the amygdala mediate hemodynamic response variability to cocaine in conscious rats.

PubMed

Watanabe, Mari A; Kucenas, Sarah; Bowman, Tamara A; Ruhlman, Melissa; Knuepfer, Mark M

2010-01-14

Stress or cocaine evokes either a large increase in systemic vascular resistance (SVR) or a smaller increase in SVR accompanied by an increase in cardiac output (designated vascular and mixed responders, respectively) in Sprague-Dawley rats. We hypothesized that the central nucleus of the amygdala (CeA) mediates this variability. Conscious, freely-moving rats, instrumented for measurement of arterial pressure and cardiac output and for drug delivery into the CeA, were given cocaine (5 mg/kg, iv, 4-6 times) and characterized as vascular (n=15) or mixed responders (n=10). Subsequently, we administered cocaine after bilateral microinjections (100 nl) of saline or selective agents in the CeA. Muscimol (80 pmol), a GABA(A) agonist, or losartan (43.4 pmol), an AT(1) receptor antagonist, attenuated the cocaine-induced increase in SVR in vascular responders, selectively, such that vascular responders were no longer different from mixed responders. The corticotropin releasing factor (CRF) antagonist, alpha-helical CRF(9-41) (15.7 pmol), abolished the difference between cardiac output and SVR in mixed and vascular responders. We conclude that greater increases in SVR observed in vascular responders are dependent on AT(1) receptor activation and, to a lesser extent on CRF receptors. Therefore, AT(1) and CRF receptors in the CeA contribute to hemodynamic response variability to intravenous cocaine.

Angiotensin II and CRF Receptors in the Central Nucleus of the Amygdala Mediate Hemodynamic Response Variability to Cocaine in Conscious Rats

PubMed Central

Watanabe, Mari A.; Kucenas, Sarah; Bowman, Tamara A.; Ruhlman, Melissa; Knuepfer, Mark M.

2009-01-01

Stress or cocaine evokes either a large increase in systemic vascular resistance (SVR) or a smaller increase in SVR accompanied by an increase in cardiac output (designated vascular and mixed responders, respectively) in Sprague-Dawley rats. We hypothesized that the central nucleus of the amygdala (CeA) mediates this variability. Conscious, freely-moving rats, instrumented for measurement of arterial pressure and cardiac output and for drug delivery into the CeA, were given cocaine (5 mg/kg, iv, 4-6 times) and characterized as vascular (n=15) or mixed responders (n=10). Subsequently, we administered cocaine after bilateral microinjections (100 nl) of saline or selective agents in the CeA. Muscimol (80 pmol), a GABAA agonist, or losartan (43.4 pmol), an AT1 receptor antagonist, attenuated the cocaine-induced increase in SVR in vascular responders, selectively, such that vascular responders were no longer different from mixed responders. The corticotropin releasing factor (CRF) antagonist, α-helical CRF9-41 (15.7 pmol), abolished the difference between cardiac output and SVR in mixed and vascular responders. We conclude that greater increases in SVR observed in vascular responders are dependent on AT1 receptor activation and, to a lesser extent on CRF receptors. Therefore, AT1 and CRF receptors in the CeA contribute to hemodynamic response variability to intravenous cocaine. PMID:19879859

Case-related factors affecting cutting errors of the proximal tibia in total knee arthroplasty assessed by computer navigation.

PubMed

Tsukeoka, Tadashi; Tsuneizumi, Yoshikazu; Yoshino, Kensuke; Suzuki, Mashiko

2018-05-01

The aim of this study was to determine factors that contribute to bone cutting errors of conventional instrumentation for tibial resection in total knee arthroplasty (TKA) as assessed by an image-free navigation system. The hypothesis is that preoperative varus alignment is a significant contributory factor to tibial bone cutting errors. This was a prospective study of a consecutive series of 72 TKAs. The amount of the tibial first-cut errors with reference to the planned cutting plane in both coronal and sagittal planes was measured by an image-free computer navigation system. Multiple regression models were developed with the amount of tibial cutting error in the coronal and sagittal planes as dependent variables and sex, age, disease, height, body mass index, preoperative alignment, patellar height (Insall-Salvati ratio) and preoperative flexion angle as independent variables. Multiple regression analysis showed that sex (male gender) (R = 0.25 p = 0.047) and preoperative varus alignment (R = 0.42, p = 0.001) were positively associated with varus tibial cutting errors in the coronal plane. In the sagittal plane, none of the independent variables was significant. When performing TKA in varus deformity, careful confirmation of the bone cutting surface should be performed to avoid varus alignment. The results of this study suggest technical considerations that can help a surgeon achieve more accurate component placement. IV.

Barriers to administering intravenous tissue plasminogen activator (tPA) for acute ischemic stroke in the emergency department: A cross-sectional survey of stroke centers.

PubMed

Hargis, Mitch; Shah, Jharna N; Mazabob, Janine; Rao, Chethan Venkatasubba; Suarez, Jose I; Bershad, Eric M

2015-08-01

The logistics involved in administration of IV tPA for acute ischemic stroke patients are complex, and may contribute to variability in door-to-needle times between different hospitals. We sought to identify practice patterns in stroke centers related to IV tPA use. We hypothesized that there would be significant variability in logistics related to ancillary staff (i.e. nursing, pharmacists) processes in the emergency room setting. A 21 question survey was distributed to attendees of the AHA/ASA Southwest Affiliate Stroke Coordinators Conference to evaluate potential barriers and delays with regards to thrombolysis for acute strokes patients in the Emergency Department setting. Answers were anonymous and aggregated to examine trends in responses. Responses were obtained from 37 of 67 (55%) stroke centers, which were located mainly in the Southwest United States. Logistical processes differed between facilities. Nursing and pharmacy carried stroke pagers in only 19% of the centers, and pharmacy responded to stroke alerts only one-third of centers. Insertion of Foley catheters and nasogastric tubes prior to tPA was routine in some of the sites. Other barriers to IV tPA administration included physician reluctance and inadequate communication between health care providers. Practices regarding logistics for giving IV tPA may be variable amongst different stroke centers. Given this potential variability, prospective evaluation to confirm these preliminary findings is warranted. Copyright © 2015 Elsevier B.V. All rights reserved.

20 CFR Appendix B to Part 718 - Standards for Administration and Interpretation of Pulmonary Function Tests. Tables B1, B2, B3...

Code of Federal Regulations, 2010 CFR

2010-04-01

... greater. (ii) The instrument shall be capable of measuring vital capacity from 0 to 7 liters BTPS. (iii... to airflow at 12 liters per second must be less than 1.5 cm H20/liter/sec. (iv) The instrument or... at flow rates up to 12 liters per second over the volume range. (ix) The spirogram shall be recorded...

20 CFR Appendix B to Part 718 - Standards for Administration and Interpretation of Pulmonary Function Tests. Tables B1, B2, B3...

Code of Federal Regulations, 2011 CFR

2011-04-01

... greater. (ii) The instrument shall be capable of measuring vital capacity from 0 to 7 liters BTPS. (iii... to airflow at 12 liters per second must be less than 1.5 cm H20/liter/sec. (iv) The instrument or... at flow rates up to 12 liters per second over the volume range. (ix) The spirogram shall be recorded...

Multi-Epoch Mid-Infrared Interferometric Observations of the Oxygen-rich Mira Variable Star RR Aql with the VLTI/MIDI Instrument

DTIC Science & Technology

2011-01-01

VLTI/ MIDI Instrument I. Karovicova,1,3 M. Wittkowski,1 D. A. Boboltz,2 E. Fossat,3 K. Ohnaka,4 and M. Scholz5,6 1European Southern Observatory...the oxygen-rich Mira variable RR Aql at 13 epochs covering 4 pulsation cycles with the MIDI instrument at the VLTI. We modeled the observed data...Variable Star RR Aql with the VLTI/ MIDI Instrument 5a. CONTRACT NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR(S) 5d. PROJECT NUMBER 5e

A multi-epoch spectroscopic study of the BAL quasar APM 08279+5255. II. Emission- and absorption-line variability time lags

NASA Astrophysics Data System (ADS)

Saturni, F. G.; Trevese, D.; Vagnetti, F.; Perna, M.; Dadina, M.

2016-03-01

Context. The study of high-redshift bright quasars is crucial to gather information about the history of galaxy assembly and evolution. Variability analyses can provide useful data on the physics of quasar processes and their relation with the host galaxy. Aims: In this study, we aim to measure the black hole mass of the bright lensed BAL QSO APM 08279+5255 at z = 3.911 through reverberation mapping, and to update and extend the monitoring of its C IV absorption line variability. Methods: We perform the first reverberation mapping of the Si IV and C IV emission lines for a high-luminosity quasar at high redshift with the use of 138 R-band photometric data and 30 spectra available over 16 years of observations. We also cross-correlate the C IV absorption equivalent width variations with the continuum light curve to estimate the recombination time lags of the various absorbers and infer the physical conditions of the ionised gas. Results: We find a reverberation-mapping time lag of ~900 rest-frame days for both Si IV and C IV emission lines. This is consistent with an extension of the BLR size-to-luminosity relation for active galactic nuclei up to a luminosity of ~1048 erg s-1, and implies a black hole mass of 1010 M⊙. Additionally, we measure a recombination time lag of ~160 days in the rest frame for the C IV narrow absorption system, which implies an electron density of the absorbing gas of ~2.5 × 104 cm-3. Conclusions: The measured black hole mass of APM 08279+5255 indicates that the quasar resides in an under-massive host-galaxy bulge with Mbulge ~ 7.5MBH, and that the lens magnification is lower than ~8. Finally, the inferred electron density of the narrow-line absorber implies a distance of the order of 10 kpc of the absorbing gas from the quasar, placing it within the host galaxy.

Temporal Synchronization Analysis for Improving Regression Modeling of Fecal Indicator Bacteria Levels

EPA Science Inventory

Multiple linear regression models are often used to predict levels of fecal indicator bacteria (FIB) in recreational swimming waters based on independent variables (IVs) such as meteorologic, hydrodynamic, and water-quality measures. The IVs used for these analyses are traditiona...

UV - EVERGLADES NATIONAL PARK FL

EPA Science Inventory

Brewer 135 is located in Everglades NP, measuring ultraviolet solar radiation. Irradiance and column ozone are derived from this data. Ultraviolet solar radiation is measured with a Brewer Mark IV, single-monochrometer, spectrophotometer manufactured by SCI-TEC Instruments, Inc. ...

Testing the limits: cautions and concerns regarding the new Wechsler IQ and Memory scales.

PubMed

Loring, David W; Bauer, Russell M

2010-02-23

The Wechsler Adult Intelligence Scale (WAIS) and the Wechsler Memory Scale (WMS) are 2 of the most common psychological tests used in clinical care and research in neurology. Newly revised versions of both instruments (WAIS-IV and WMS-IV) have recently been published and are increasingly being adopted by the neuropsychology community. There have been significant changes in the structure and content of both scales, leading to the potential for inaccurate patient classification if algorithms developed using their predecessors are employed. There are presently insufficient clinical data in neurologic populations to insure their appropriate application to neuropsychological evaluations. We provide a perspective on these important new neuropsychological instruments, comment on the pressures to adopt these tests in the absence of an appropriate evidence base supporting their incremental validity, and describe the potential negative impact on both patient care and continuing research applications.

Violent Recidivism: A Long-Time Follow-Up Study of Mentally Disordered Offenders

PubMed Central

Nilsson, Thomas; Wallinius, Märta; Gustavson, Christina; Anckarsäter, Henrik; Kerekes, Nóra

2011-01-01

Background In this prospective study, mentally disordered perpetrators of severe violent and/or sexual crimes were followed through official registers for 59 (range 8 to 73) months. The relapse rate in criminality was assessed, compared between offenders sentenced to prison versus forensic psychiatric care, and the predictive ability of various risk factors (criminological, clinical, and of structured assessment instruments) was investigated. Method One hundred perpetrators were consecutively assessed between 1998 and 2001 by a clinical battery of established instruments covering DSM-IV diagnoses, psychosocial background factors, and structured assessment instruments (HCR-20, PCL-R, and life-time aggression (LHA)). Follow-up data was collected from official registers for: (i) recidivistic crimes, (ii) crimes during ongoing sanction. Results Twenty subjects relapsed in violent criminality during ongoing sanctions (n = 6) or after discharge/parole (n = 14). Individuals in forensic psychiatric care spent significantly more time at liberty after discharge compared to those in prison, but showed significantly fewer relapses. Criminological (age at first conviction), and clinical (conduct disorder and substance abuse/dependence) risk factors, as well as scores on structured assessment instruments, were moderately associated with violent recidivism. Logistic regression analyses showed that the predictive ability of criminological risk factors versus clinical risk factors combined with scores from assessment instruments was comparable, with each set of variables managing to correctly classify about 80% of all individuals, but the only predictors that remained significant in multiple models were criminological (age at first conviction, and a history of substance abuse among primary relatives). Conclusions Only one in five relapsed into serious criminality, with significantly more relapses among subjects sentenced to prison as compared to forensic psychiatric care. Criminological risk factors tended to be the best predictors of violent relapses, while few synergies were seen when the risk factors were combined. Overall, the predictive validity of common risk factors for violent criminality was rather weak. PMID:22022445

In-vehicle signing functions of an in-vehicle information system

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

Tufano, D.R.; Knee, H.E.; Spelt, P.F.

The definition of In-Vehicle Signing (IVS) functions was guided by the principles of traffic engineering as they apply to the design and placement of roadway signs. Because of the dynamic and active nature of computing, communications, and display technology, IVS can fulfill the signing principles of traffic engineering in ways that have been impossible with conventional signage. Current signing technology represents a series of compromises of these principles, especially the data and equations contributing to the calculation of required sight distance. A number of conditions relevant to sight distance are quite variable, e.g.: vehicle speed, visibility, weather, and driver reactionmore » time. However, conventional signing requires that there are fixed values of each variable for the determination of (e.g.) legibility distance. IVS, on the other hand, will be able to tailor the timing of sign presentation to the dynamically diverse variable values of all of these conditions. A clear, in-vehicle sign display, adaptive to ambient and driver conditions, will in fact obviate the entire issue of sign legibility. These capabilities, together with information filtering functions, will truly enhance the presentation of sign information to drivers. The development of IVS is a critical step in the development of an integrated In-Vehicle Information System (IVIS).« less

Effects of marketing group and production focus on quality and variability of adipose tissue and bellies sourced from a commercial processing facility.

PubMed

Overholt, M F; Arkfeld, E K; Wilson, K B; Mohrhauser, D A; King, D A; Wheeler, T L; Dilger, A C; Shackelford, S D; Boler, D D

2016-12-01

Objectives were to determine the effects of marketing group on quality and variability of belly and adipose tissue quality traits of pigs sourced from differing production focuses (lean vs. quality). Pigs ( = 8,042) raised in 8 barns representing 2 seasons (cold and hot) were used. Three groups were marketed from each barn with 2 barns per production focus marketed per season. Data were collected on 7,684 carcasses at a commercial abattoir. Fresh belly characteristics, American Oil Chemists' Society iodine value (AOCS-IV), and near-infrared iodine value were measured on a targeted 50, 10, and 100% of carcasses, respectively. Data were analyzed as a split-plot design in the MIXED procedure of SAS 9.4 with production focus as the whole-plot factor and marketing group as the split-plot factor. Barn (block), season, and sex were random variables. A multivariance model was fit using the REPEATED statement with the marketing group × production focus interaction as the grouping variable. Variances for production focus and marketing groups were calculated using the MEANS procedure. Homogeneity of variance was tested on raw data using the Levene's test of the GLM procedure. Among quality focus carcasses, marketing group 3 bellies weighed less ( ≤ 0.03) than those from either marketing group 1 or 2, but there was no difference ( ≥ 0.99) among marketing groups of the lean focus carcasses. There was no effect ( ≥ 0.11) of production focus on fresh belly measures, SFA, or iodine value (IV), but lean focus carcasses had decreased ( = 0.04) total MUFA and increased ( < 0.01) total PUFA compared with quality focus carcasses. Marketing group did not affect ( ≥ 0.10) fresh belly dimensions, total SFA, total MUFA, total PUFA, or IV. Belly weight, flop score, width, and all depth measurements were less variable ( ≤ 0.01); whereas, belly length, total SFA, and total MUFA were more variable ( < 0.0001) in lean focus carcasses than in quality focus carcasses. There was no difference ( ≥ 0.17) in total PUFA or AOCS-IV variability between production focuses. Variance of flop score, total MUFA, and total PUFA were not equal ( ≤ 0.01) among marketing groups. Belly weight, length, width, and depth measurements; SFA; or IV variance did not differ ( ≥ 0.06) among marketing groups. Although a multiple-marketing strategy was effective at minimizing differences in belly characteristics, differences in the variability of these traits exist among marketing groups and are likely dependent on the production system used.

An instrumental variable random-coefficients model for binary outcomes

PubMed Central

Chesher, Andrew; Rosen, Adam M

2014-01-01

In this paper, we study a random-coefficients model for a binary outcome. We allow for the possibility that some or even all of the explanatory variables are arbitrarily correlated with the random coefficients, thus permitting endogeneity. We assume the existence of observed instrumental variables Z that are jointly independent with the random coefficients, although we place no structure on the joint determination of the endogenous variable X and instruments Z, as would be required for a control function approach. The model fits within the spectrum of generalized instrumental variable models, and we thus apply identification results from our previous studies of such models to the present context, demonstrating their use. Specifically, we characterize the identified set for the distribution of random coefficients in the binary response model with endogeneity via a collection of conditional moment inequalities, and we investigate the structure of these sets by way of numerical illustration. PMID:25798048

OSO-8 observations of the impulsive phase of solar flares in the transition-zone and corona

NASA Technical Reports Server (NTRS)

Lites, B. W.; Bruner, E. C., Jr.; Wolfson, C. J.

1981-01-01

Several solar flares were observed from their onset in C IV 1548.2 A and 1-8 A X-rays using instruments on OSO-8. It is found that impulsive brightening in C IV is often accompanied by redshifts, interpreted as downflows, of the order of 80 km/s. The maximum soft X-ray intensity usually arrives several minutes after the maximum C IV intensity. The most energetic C IV event observed shows a small blueshift just before reaching maximum intensity; estimates of the mass flux associated with this upflow through the transition zone are consistent with the increase of mass in the coronal loops as observed in soft X-rays. Finally, it is suggested that the frequent occurrence of violent dynamical processes at the onset of the flare is associated with the initial energy release mechanism.

[Neurocognitive disorders in DSM-5: pervasive changes in the diagnostics of dementia].

PubMed

Maier, W; Barnikol, U B

2014-05-01

The Diagnostic and Statistical Manual of Mental Disorders (DSM-5) proposes an innovative chapter on neurocognitive disorders (NCD) as a substitute for the dementia, delirium and amnestic disorders chapter in DSM-IV. This NCD chapter promotes a most innovative change compared to DSM-IV. While the term delirium is preserved, the commonly used term dementia does not occur as a diagnostic entity. Neurocognitive disorders are more inclusive than dementias; they also cover early prodromal stages of dementias below the DSM-IV threshold. The diagnosis of NCDs requires essentially neuropsychological testing preferentially with standardized instruments. Special focus is given to etiological subtyping taking former diagnostic consensus processes by expert groups into consideration. The subsequent more extensive concept of NCD also allows the diagnosis of etiological-specific prodromal states of cognitive impairments. The changes from DSM-IV to DSM-5 are critically discussed.

Cardiopulmonary, blood and peritoneal fluid alterations associated with abdominal insufflation of carbon dioxide in standing horses.

PubMed

Latimer, F G; Eades, S C; Pettifer, G; Tetens, J; Hosgood, G; Moore, R M

2003-05-01

Abdominal insufflation is performed routinely during laparoscopy in horses to improve visualisation and facilitate instrument and visceral manipulations during surgery. It has been shown that high-pressure pneumoperitoneum with carbon dioxide (CO2) has deleterious cardiopulmonary effects in dorsally recumbent, mechanically ventilated, halothane-anaesthetised horses. There is no information on the effects of CO2 pneumoperitoneum on cardiopulmonary function and haematology, plasma chemistry and peritoneal fluid (PF) variables in standing sedated horses during laparoscopic surgery. To determine the effects of high pressure CO2 pneumoperitoneum in standing sedated horses on cardiopulmonary function, blood gas, haematology, plasma chemistry and PF variables. Six healthy, mature horses were sedated with an i.v. bolus of detomidine (0.02 mg/kg bwt) and butorphanol (0.02 mg/kg bwt) and instrumented to determine the changes in cardiopulmonary function, haematology, serum chemistry and PF values during and after pneumoperitoneum with CO2 to 15 mmHg pressure for standing laparoscopy. Each horse was assigned at random to either a standing left flank exploratory laparoscopy (LFL) with CO2 pneumoperitoneum or sham procedure (SLFL) without insufflation, and instrumented for measurement of cardiopulmonary variables. Each horse underwent a second procedure in crossover fashion one month later so that all 6 horses had both an LFL and SLFL performed. Cardiopulmonary variables and blood gas analyses were obtained 5 mins after sedation and every 15 mins during 60 mins baseline (BL), insufflation (15 mmHg) and desufflation. Haematology, serum chemistry analysis and PF analysis were performed at BL, insufflation and desufflation, and 24 h after the conclusion of each procedure. Significant decreases in heart rate, cardiac output and cardiac index and significant increases in mean right atrial pressure, systemic vascular resistance and pulmonary vascular resistance were recorded immediately after and during sedation in both groups of horses. Pneumoperitoneum with CO2 at 15 mmHg had no significant effect on cardiopulmonary function during surgery. There were no significant differences in blood gas, haematology or plasma chemistry values within or between groups at any time interval during the study. There was a significant increase in the PF total nucleated cell count 24 h following LFL compared to baseline values for LFL or SLFL at 24 h. There were no differences in PF protein concentrations within or between groups at any time interval. Pneumoperitoneum with CO2 during standing laparoscopy in healthy horses does not cause adverse alterations in cardiopulmonary, haematology or plasma chemistry variables, but does induce a mild inflammatory response within the peritoneal cavity. High pressure (15 mmHg) pneumoperitoneum in standing sedated mature horses for laparoscopic surgery can be performed safely without any short-term or cumulative adverse effects on haemodynamic or cardiopulmonary function.

Self-report assessment of the DSM-IV personality disorders. Measurement of trait and distress characteristics: the ADP-IV.

PubMed

Schotte, C K; de Doncker, D; Vankerckhoven, C; Vertommen, H; Cosyns, P

1998-09-01

Self-report instruments assessing the DSM personality disorders are characterized by overdiagnosis due to their emphasis on the measurement of personality traits rather than the impairment and distress associated with the criteria. The ADP-IV, a Dutch questionnaire, introduces an alternative assessment method: each test item assesses 'Trait' as well as 'Distress/impairment' characteristics of a DSM-IV criterion. This item format allows dimensional as well as categorical diagnostic evaluations. The present study explores the validity of the ADP-IV in a sample of 659 subjects of the Flemish population. The dimensional personality disorder subscales, measuring Trait characteristics, are internally consistent and display a good concurrent validity with the Wisconsin Personality Disorders Inventory. Factor analysis at the item-level resulted in 11 orthogonal factors, describing personality dimensions such as psychopathy, social anxiety and avoidance, negative affect and self-image. Factor analysis at the subscale-level identified two basic dimensions, reflecting hostile (DSM-IV Cluster B) and anxious (DSM-IV Cluster C) interpersonal attitudes. Categorical ADP-IV diagnoses are obtained using scoring algorithms, which emphasize the Trait or the Distress concepts in the diagnostic evaluation. Prevalences of ADP-IV diagnoses of any personality disorder according to these algorithms vary between 2.28 and 20.64%. Although further research in clinical samples is required, the present results support the validity of the ADP-IV and the potential of the measurement of trait and distress characteristics as a method for assessing personality pathology.

Initial Construction of a Maladaptive Personality Trait Model and Inventory for DSM-5

PubMed Central

Krueger, Robert F.; Derringer, Jaime; Markon, Kristian E.; Watson, David; Skodol, Andrew E.

2012-01-01

Background DSM-IV-TR suggests that clinicians should assess clinically relevant personality traits that do not necessarily constitute a formal personality disorder, and should note these traits on Axis II, but DSM-IV-TR does not provide a trait model to guide the clinician. Our goal was to provide a provisional trait model and a preliminary corresponding assessment instrument, in our roles as members of the DSM-5 personality and personality disorders workgroup and workgroup advisors. Methods An initial list of specific traits and domains (broader groups of traits) was derived from DSM-5 literature reviews and workgroup deliberations, with a focus on capturing maladaptive personality characteristics deemed clinically salient, including those related to the criteria for DSM-IV-TR personality disorders (PDs). The model and instrument were then developed iteratively using data from community samples of treatment seeking participants. The analytic approach relied on tools of modern psychometrics (e.g., item response theory models). Results Twenty-five reliably measured core elements of personality description emerged that, together, delineate five broad domains of maladaptive personality variation: negative affect, detachment, antagonism, disinhibition, and psychoticism. Conclusions We developed a maladaptive personality trait model and corresponding instrument as a step on the path toward helping users of DSM-5 assess traits that may or may not constitute a formal PD. The inventory we developed is reprinted in its entirety in the supplementary materials, with the goal of encouraging additional refinement and development by other investigators prior to the finalization of DSM-5. Continuing discussion should focus on various options for integrating personality traits into DSM-5. PMID:22153017

Considerations in comparing the U.S. Geological Survey one‐year induced‐seismicity hazard models with “Did You Feel It?” and instrumental data

USGS Publications Warehouse

White, Isabel; Liu, Taojun; Luco, Nicolas; Liel, Abbie

2017-01-01

The recent steep increase in seismicity rates in Oklahoma, southern Kansas, and other parts of the central United States led the U.S. Geological Survey (USGS) to develop, for the first time, a probabilistic seismic hazard forecast for one year (2016) that incorporates induced seismicity. In this study, we explore a process to ground‐truth the hazard model by comparing it with two databases of observations: modified Mercalli intensity (MMI) data from the “Did You Feel It?” (DYFI) system and peak ground acceleration (PGA) values from instrumental data. Because the 2016 hazard model was heavily based on earthquake catalogs from 2014 to 2015, this initial comparison utilized observations from these years. Annualized exceedance rates were calculated with the DYFI and instrumental data for direct comparison with the model. These comparisons required assessment of the options for converting hazard model results and instrumental data from PGA to MMI for comparison with the DYFI data. In addition, to account for known differences that affect the comparisons, the instrumental PGA and DYFI data were declustered, and the hazard model was adjusted for local site conditions. With these adjustments, examples at sites with the most data show reasonable agreement in the exceedance rates. However, the comparisons were complicated by the spatial and temporal completeness of the instrumental and DYFI observations. Furthermore, most of the DYFI responses are in the MMI II–IV range, whereas the hazard model is oriented toward forecasts at higher ground‐motion intensities, usually above about MMI IV. Nevertheless, the study demonstrates some of the issues that arise in making these comparisons, thereby informing future efforts to ground‐truth and improve hazard modeling for induced‐seismicity applications.

Testing concordance of instrumental variable effects in generalized linear models with application to Mendelian randomization

PubMed Central

Dai, James Y.; Chan, Kwun Chuen Gary; Hsu, Li

2014-01-01

Instrumental variable regression is one way to overcome unmeasured confounding and estimate causal effect in observational studies. Built on structural mean models, there has been considerale work recently developed for consistent estimation of causal relative risk and causal odds ratio. Such models can sometimes suffer from identification issues for weak instruments. This hampered the applicability of Mendelian randomization analysis in genetic epidemiology. When there are multiple genetic variants available as instrumental variables, and causal effect is defined in a generalized linear model in the presence of unmeasured confounders, we propose to test concordance between instrumental variable effects on the intermediate exposure and instrumental variable effects on the disease outcome, as a means to test the causal effect. We show that a class of generalized least squares estimators provide valid and consistent tests of causality. For causal effect of a continuous exposure on a dichotomous outcome in logistic models, the proposed estimators are shown to be asymptotically conservative. When the disease outcome is rare, such estimators are consistent due to the log-linear approximation of the logistic function. Optimality of such estimators relative to the well-known two-stage least squares estimator and the double-logistic structural mean model is further discussed. PMID:24863158

THE SLOAN DIGITAL SKY SURVEY REVERBERATION MAPPING PROJECT: RAPID C iv BROAD ABSORPTION LINE VARIABILITY

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

Grier, C. J.; Brandt, W. N.; Trump, J. R.

2015-06-10

We report the discovery of rapid variations of a high-velocity C iv broad absorption line trough in the quasar SDSS J141007.74+541203.3. This object was intensively observed in 2014 as a part of the Sloan Digital Sky Survey Reverberation Mapping Project, during which 32 epochs of spectroscopy were obtained with the Baryon Oscillation Spectroscopic Survey spectrograph. We observe significant (>4σ) variability in the equivalent width (EW) of the broad (∼4000 km s{sup −1} wide) C iv trough on rest-frame timescales as short as 1.20 days (∼29 hr), the shortest broad absorption line variability timescale yet reported. The EW varied by ∼10%more » on these short timescales, and by about a factor of two over the duration of the campaign. We evaluate several potential causes of the variability, concluding that the most likely cause is a rapid response to changes in the incident ionizing continuum. If the outflow is at a radius where the recombination rate is higher than the ionization rate, the timescale of variability places a lower limit on the density of the absorbing gas of n{sub e} ≳ 3.9 × 10{sup 5} cm{sup −3}. The broad absorption line variability characteristics of this quasar are consistent with those observed in previous studies of quasars, indicating that such short-term variability may in fact be common and thus can be used to learn about outflow characteristics and contributions to quasar/host-galaxy feedback scenarios.« less

Determinants of quality of life of patients with heart failure and iron deficiency treated with ferric carboxymaltose: FAIR-HF sub-analysis.

PubMed

Gutzwiller, Florian S; Pfeil, Alena M; Comin-Colet, Josep; Ponikowski, Piotr; Filippatos, Gerasimos; Mori, Claudio; Braunhofer, Peter G; Szucs, Thomas D; Schwenkglenks, Matthias; Anker, Stefan D

2013-10-09

Heart failure (HF) is a burden to patients and health care systems. The objectives of HF treatment are to improve health related quality of life (HRQoL) and reduce mortality and morbidity. We aimed to evaluate determinants of health-related quality of life (HRQoL) in patients with iron deficiency and HF treated with intravenous (i.v.) iron substitution or placebo. A randomised, double-blind, placebo-controlled trial (n = 459) in iron-deficient chronic heart failure (CHF) patients with or without anaemia studied clinical and HRQoL benefits of i.v. iron substitution using ferric carboxymaltose (FCM) over a 24-week trial period. Multivariate analysis was carried out with various clinical variables as independent variables and HRQoL measures as dependent variables. Mean change from baseline of European Quality of Life - 5 Dimensions (EQ-5D) (value set-based) utilities (on a 0 to 100 scale) at week 24 was 8.91 (i.v. iron) and 0.68 (placebo; p < 0.01). In a multivariate analysis excluding baseline HRQoL, a higher exercise tolerance and i.v. iron substitution positively influenced HRQoL, whereas impaired renal function and a history of stroke had a negative effect. The level of HRQoL was also influenced by country of residence. When baseline HRQoL was factored in, the multivariate model remained stable. In this study, i.v. iron substitution, exercise tolerance, stroke, country of residence and renal function influenced measures of HRQoL in patients with heart failure and iron deficiency. © 2013.

A Handbook of Descriptive and Practical Astronomy

NASA Astrophysics Data System (ADS)

Chambers, George Frederick

2010-06-01

Book I. A Sketch of the Solar System: 1. The sun; 2. The planets; 3. Vulcan; 4. Mercury; 5. Venus; 6. The earth; 7. The moon; 8. Mars; 9. The minor planets; 10. Jupiter; 11. Saturn; 12. Uranus; 13. Neptune; Book II. Eclipses and their Associated Phenomena: 1. General outlines; 2. Eclipses of the sun; 3. The total eclipse of the sun of July 28, 1851; 4. The annular eclipse of the sun of March 14-15, 1858; 5. The total eclipse of the sun of July 18, 1860; 6. Historical notices; 7. Eclipses of the moon; 8. Suggestions for observing annular eclipses of the sun; 9. Transits of the inferior planets; 10. Occultations; Book III. The Tides: 1. Introduction; 2. Local disturbing influences; Book IV. Miscellaneous Astronomical Phenomena: 1. Variation in the obliquity of the ecliptic; 2. Aberration; 3. Refraction; Book V. Comets: 1. General remarks; 2. Periodic comets; 3. Remarkable comets; 4. Cometary statistics; 5. Historical notices; Book VI. Chronological Astronomy: 1. What time is; 2. Hours; 3. Means of measuring time; 4. The Dominical or Sunday letter; 5. Tables for the conversion of time; Book VII. The Starry Heavens: 1. The Pole-Star; 2. Double stars; 3. Variable stars; 4. Clusters and nebulae; 5. The Milky Way; 6. The constellations; Book VIII. Astronomical Instruments: 1. Telescopes; 2. Telescope stands; 3. The equatorial; 4. The transit instrument; 5. Other astronomical instruments; 6. History of the telescope; Book IX. A Sketch of the History of Astronomy; Book X. Meteoric Astronomy: 1. Classification of the subject; 2. The origin of aërolites; 3. Shooting stars; Appendices; Index.

Comparing the Personality Disorder Interview for DSM-IV (PDI-IV) and SCID-II borderline personality disorder scales: an item-response theory analysis.

PubMed

Huprich, Steven K; Paggeot, Amy V; Samuel, Douglas B

2015-01-01

One-hundred sixty-nine psychiatric outpatients and 171 undergraduate students were assessed with the Personality Disorder Interview-IV (PDI-IV; Widiger, Mangine, Corbitt, Ellis, & Thomas, 1995) and the Structured Clinical Interview for DSM-IV Axis II disorders (SCID-II; First, Gibbon, Spitzer, Williams, & Benjamin, 1997) for borderline personality disorder (BPD). Eighty individuals met PDI-IV BPD criteria, whereas 34 met SCID-II BPD criteria. Dimensional ratings of both measures were highly intercorrelated (rs = .78, .75), and item-level interrater reliability fell in the good to excellent range. An item-response theory analysis was performed to investigate whether properties of the items from each interview could help understand these differences. The limited agreement seemed to be explained by differences in the response options across the two interviews. We found that suicidal behavior was among the most discriminating criteria on both instruments, whereas dissociation and difficulty controlling anger had the 2 lowest alpha parameter values. Finally, those meeting BPD criteria on both interviews had higher levels of anxiety, depression, and more impairments in object relations than those meeting criteria on just the PDI-IV. These findings suggest that the choice of measure has a notable effect on the obtained diagnostic prevalence and the level of BPD severity that is detected.

Compliance and coping potential of cancer patients treated in liaison-consultation psychiatry.

PubMed

Grube, Michael

2006-01-01

To investigate the impact of psychiatric illness, aggression, and other covarying variables on the compliance and coping potential of cancer patients treated in liaison-consultation psychiatry. The study involves 270 cancer patients who were admitted to the oncology ward for diagnosis and treatment. Each patient took part in a psychiatric consultation. We used the Transplant Evaluation Rating Scale (TERS), which provides a system for differentially recording the patient's compliance and coping potential (total score for the TERS items 3-10). Following standardization using the basic psychooncological documentation (PO-BADO), the demographic variables were recorded. We also identified the internal processes which each patient used to deal with the disease using criteria established by Kübler-Ross as well as the phases of cancer experience according to Fawzy. Twenty-three variables were checked for their relationship to the coping and compliance potential. For 13 of these, the Mann-Whitney U-test or Spearmann-Rank correlation calculated exceeded the required Bonferroni-adjusted significance level. The calculation of an ordinal regression model containing these significant single variables showed that the following variables are associated with a lower compliance and coping potential according to their estimate (Beta-value): aggression as the dominant form of dealing internally with cancer (Kübler-Ross), pre-existing DSM IV Axis 1 psychiatric disorders, carcinoma-induced psychiatric disorders, necessity of treatment with neuroleptics and male gender. Acceptance as the dominant form of dealing internally with cancer (Kübler-Ross) is strongly associated with a higher compliance and coping potential. The results show that the compliance and coping potential of oncological in-patients can be comprehensively described by the Transplant Evaluation Rating Scale. The instruments of measurement used in the study are also useful for describing risk factors associated with low levels of compliance and coping potential.

48 CFR 10.002 - Procedures.

Code of Federal Regulations, 2010 CFR

2010-10-01

... officer may use market research conducted within 18 months before the award of any task or delivery order... or business publications. (iv) Querying the Governmentwide database of contracts and other procurement instruments intended for use by multiple agencies available at http://www.contractdirectory.gov...

Determining the Attitudes of Undergraduate Students Having Vocational Music Education towards Individual Instrument Course According to Different Variables

ERIC Educational Resources Information Center

Uluçay, Taner

2017-01-01

This study was carried out in order to determine attitudes of undergraduate students who studied music vocationally towards the individual instrument course according to the variables of grade, gender, individual instrument and graduated high school type. The research data were obtained from 102 undergraduate students studying in Erzincan…

Development and validation of a new instrument to evaluate the ease of use of patient-controlled analgesic modalities for postoperative patients.

PubMed

Harding, Gale; Schein, Jeff R; Nelson, Winnie W; Vallow, Sue; Olson, William H; Hewitt, David J; Polomano, Rosemary C

2010-03-01

To describe the development and psychometric evaluation of a questionnaire assessing the ease of use that patients associate with patient-controlled analgesia (PCA) modalities. Qualitative interviews were conducted with patients who had experience with intravenous (IV) PCA for postoperative pain management to generate items relevant to the ease of using PCA modalities. The content validity of the resulting questionnaire was examined through follow-up patient interviews, and an expert panel reviewed the questionnaire. Cognitive debriefing interviews were conducted with patients to determine the clarity and content of the instructions, items, and response scales, and the ease of completing the instrument. Psychometric evaluation was performed with patients who had undergone surgery and received IV PCA for postoperative pain management. Item and scale quality and the internal consistency reliability of the questionnaire were assessed. Construct validity was evaluated by examining the relationship between subscales of the questionnaire with patient-reported outcome measures. Known-groups validity was determined by assessing the instrument's ability to differentiate between patients with versus without an IV PCA problem. A potential limitation of this study was the exclusive sampling of patients who had experience with IV PCA. The Patient Ease-of-Care (EOC) Questionnaire included 23 items in the following subscales: Confidence with Device, Comfort with Device, Movement, Dosing Confidence, Pain Control, Knowledge/Understanding, and Satisfaction. Coefficient alpha reliability estimates were ≥ 0.66 for Overall EOC (includes all subscales except Satisfaction) and all EOC subscales. Construct validity was supported by the moderate relationship between the Pain Control subscale and measures of pain severity and pain interference; additional evidence of construct validity was provided by correlations of the Confidence with Device subscale, the Satisfaction subscale, and Overall EOC with measures of pain severity, pain interference, and satisfaction. Significant mean score differences were reported between participants with and without IV PCA problems for Overall EOC and for the Comfort with Device, Confidence with Device, Movement, Pain Control, and Satisfaction subscales indicating known-groups validity. Results provide evidence for the reliability and validity of the Patient EOC Questionnaire as a measure of the ease of use that patients associate with PCA systems and may be useful for evaluating emerging PCA modalities.

Variability in the prevalence of adult ADHD in treatment seeking substance use disorder patients: results from an international multi-center study exploring DSM-IV and DSM-5 criteria.

PubMed

van de Glind, Geurt; Konstenius, Maija; Koeter, Maarten W J; van Emmerik-van Oortmerssen, Katelijne; Carpentier, Pieter-Jan; Kaye, Sharlene; Degenhardt, Louisa; Skutle, Arvid; Franck, Johan; Bu, Eli-Torild; Moggi, Franz; Dom, Geert; Verspreet, Sofie; Demetrovics, Zsolt; Kapitány-Fövény, Máté; Fatséas, Melina; Auriacombe, Marc; Schillinger, Arild; Møller, Merete; Johnson, Brian; Faraone, Stephen V; Ramos-Quiroga, J Antoni; Casas, Miguel; Allsop, Steve; Carruthers, Susan; Schoevers, Robert A; Wallhed, Sara; Barta, Csaba; Alleman, Peter; Levin, Frances R; van den Brink, Wim

2014-01-01

Available studies vary in their estimated prevalence of attention deficit/hyperactivity disorder (ADHD) in substance use disorder (SUD) patients, ranging from 2 to 83%. A better understanding of the possible reasons for this variability and the effect of the change from DSM-IV to DSM-5 is needed. A two stage international multi-center, cross-sectional study in 10 countries, among patients form inpatient and outpatient addiction treatment centers for alcohol and/or drug use disorder patients. A total of 3558 treatment seeking SUD patients were screened for adult ADHD. A subsample of 1276 subjects, both screen positive and screen negative patients, participated in a structured diagnostic interview. Prevalence of DSM-IV and DSM-5 adult ADHD varied for DSM-IV from 5.4% (CI 95%: 2.4-8.3) for Hungary to 31.3% (CI 95%:25.2-37.5) for Norway and for DSM-5 from 7.6% (CI 95%: 4.1-11.1) for Hungary to 32.6% (CI 95%: 26.4-38.8) for Norway. Using the same assessment procedures in all countries and centers resulted in substantial reduction of the variability in the prevalence of adult ADHD reported in previous studies among SUD patients (2-83%→5.4-31.3%). The remaining variability was partly explained by primary substance of abuse and by country (Nordic versus non-Nordic countries). Prevalence estimates for DSM-5 were slightly higher than for DSM-IV. Given the generally high prevalence of adult ADHD, all treatment seeking SUD patients should be screened and, after a confirmed diagnosis, treated for ADHD since the literature indicates poor prognoses of SUD in treatment seeking SUD patients with ADHD. Copyright © 2013 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.

Variability in the prevalence of adult ADHD in treatment seeking substance use disorder patients: Results from an international multi-center study exploring DSM-IV and DSM-5 criteria☆☆

PubMed Central

van de Glind, Geurt; Konstenius, Maija; Koeter, Maarten W.J.; van Emmerik-van Oortmerssen, Katelijne; Carpentier, Pieter-Jan; Kaye, Sharlene; Degenhardt, Louisa; Skutle, Arvid; Franck, Johan; Bu, Eli-Torild; Moggi, Franz; Dom, Geert; Verspreet, Sofie; Demetrovics, Zsolt; Kapitány-Fövény, Máté; Fatséas, Melina; Auriacombe, Marc; Schillinger, Arild; Møller, Merete; Johnson, Brian; Faraone, Stephen V.; Ramos-Quiroga, J. Antoni; Casas, Miguel; Allsop, Steve; Carruthers, Susan; Schoevers, Robert A.; Wallhed, Sara; Barta, Csaba; Alleman, Peter; Levin, Frances R.; van den Brink, Wim

2014-01-01

Background Available studies vary in their estimated prevalence of attention deficit/hyperactivity disorder (ADHD) in substance use disorder (SUD) patients, ranging from 2 to 83%. A better understanding of the possible reasons for this variability and the effect of the change from DSM-IV to DSM-5 is needed. Methods A two stage international multi-center, cross-sectional study in 10 countries, among patients form inpatient and outpatient addiction treatment centers for alcohol and/or drug use disorder patients. A total of 3558 treatment seeking SUD patients were screened for adult ADHD. A subsample of 1276 subjects, both screen positive and screen negative patients, participated in a structured diagnostic interview. Results Prevalence of DSM-IV and DSM-5 adult ADHD varied for DSM-IV from 5.4% (CI 95%: 2.4–8.3) for Hungary to 31.3% (CI 95%:25.2–37.5) for Norway and for DSM-5 from 7.6% (CI 95%: 4.1–11.1) for Hungary to 32.6% (CI 95%: 26.4–38.8) for Norway. Using the same assessment procedures in all countries and centers resulted in substantial reduction of the variability in the prevalence of adult ADHD reported in previous studies among SUD patients (2–83%→ 5.4–31.3%). The remaining variability was partly explained by primary substance of abuse and by country (Nordic versus non-Nordic countries). Prevalence estimates for DSM-5 were slightly higher than for DSM-IV. Conclusions Given the generally high prevalence of adult ADHD, all treatment seeking SUD patients should be screened and, after a confirmed diagnosis, treated for ADHD since the literature indicates poor prognoses of SUD in treatment seeking SUD patients with ADHD. PMID:24156882

Instrumental variables estimation of exposure effects on a time-to-event endpoint using structural cumulative survival models.

PubMed

Martinussen, Torben; Vansteelandt, Stijn; Tchetgen Tchetgen, Eric J; Zucker, David M

2017-12-01

The use of instrumental variables for estimating the effect of an exposure on an outcome is popular in econometrics, and increasingly so in epidemiology. This increasing popularity may be attributed to the natural occurrence of instrumental variables in observational studies that incorporate elements of randomization, either by design or by nature (e.g., random inheritance of genes). Instrumental variables estimation of exposure effects is well established for continuous outcomes and to some extent for binary outcomes. It is, however, largely lacking for time-to-event outcomes because of complications due to censoring and survivorship bias. In this article, we make a novel proposal under a class of structural cumulative survival models which parameterize time-varying effects of a point exposure directly on the scale of the survival function; these models are essentially equivalent with a semi-parametric variant of the instrumental variables additive hazards model. We propose a class of recursive instrumental variable estimators for these exposure effects, and derive their large sample properties along with inferential tools. We examine the performance of the proposed method in simulation studies and illustrate it in a Mendelian randomization study to evaluate the effect of diabetes on mortality using data from the Health and Retirement Study. We further use the proposed method to investigate potential benefit from breast cancer screening on subsequent breast cancer mortality based on the HIP-study. © 2017, The International Biometric Society.

A global database with parallel measurements to study non-climatic changes

NASA Astrophysics Data System (ADS)

Venema, Victor; Auchmann, Renate; Aguilar, Enric; Auer, Ingeborg; Azorin-Molina, Cesar; Brandsma, Theo; Brunetti, Michele; Dienst, Manuel; Domonkos, Peter; Gilabert, Alba; Lindén, Jenny; Milewska, Ewa; Nordli, Øyvind; Prohom, Marc; Rennie, Jared; Stepanek, Petr; Trewin, Blair; Vincent, Lucie; Willett, Kate; Wolff, Mareile

2016-04-01

In this work we introduce the rationale behind the ongoing compilation of a parallel measurements database, in the framework of the International Surface Temperatures Initiative (ISTI) and with the support of the World Meteorological Organization. We intend this database to become instrumental for a better understanding of inhomogeneities affecting the evaluation of long-term changes in daily climate data. Long instrumental climate records are usually affected by non-climatic changes, due to, e.g., (i) station relocations, (ii) instrument height changes, (iii) instrumentation changes, (iv) observing environment changes, (v) different sampling intervals or data collection procedures, among others. These so-called inhomogeneities distort the climate signal and can hamper the assessment of long-term trends and variability of climate. Thus to study climatic changes we need to accurately distinguish non-climatic and climatic signals. The most direct way to study the influence of non-climatic changes on the distribution and to understand the reasons for these biases is the analysis of parallel measurements representing the old and new situation (in terms of e.g. instruments, location, different radiation shields, etc.). According to the limited number of available studies and our understanding of the causes of inhomogeneity, we expect that they will have a strong impact on the tails of the distribution of air temperatures and most likely of other climate elements. Our abilities to statistically homogenize daily data will be increased by systematically studying different causes of inhomogeneity replicated through parallel measurements. Current studies of non-climatic changes using parallel data are limited to local and regional case studies. However, the effect of specific transitions depends on the local climate and the most interesting climatic questions are about the systematic large-scale biases produced by transitions that occurred in many regions. Important potentially biasing transitions are the adoption of Stevenson screens, relocations (to airports) efforts to reduce undercatchment of precipitation or the move to automatic weather stations. Thus a large global parallel dataset is highly desirable as it allows for the study of systematic biases in the global record. We are interested in data from all climate variables at all time scales; from annual to sub-daily. High-resolution data is important for understanding the physical causes for the differences between the parallel measurements. For the same reason, we are also interested in other climate variables measured at the same station. For example, in case of parallel air temperature measurements, the influencing factors are expected to be global radiation, wind, humidity and cloud cover; in case of parallel precipitation measurements, wind and wet-bulb temperature are potentially important. Metadata that describe the parallel measurements is as important as the data itself and will be collected as well. For example, the types of the instruments, their siting, height, maintenance, etc. Because they are widely used to study moderate extremes, we will compute the indices of the Expert Team on Climate Change Detection and Indices (ETCCDI). In case the daily data cannot be shared, we would appreciate contributions containing these indices from parallel measurements. For more information: http://tinyurl.com/ISTI-Parallel

The Study of Programs of Instruction for Handicapped Children and Youth in Day and Residential Facilities. Volume IV. Survey Instruments and Materials for the Survey of Separate Facilities and the Survey of SEA Special Education Divisions.

ERIC Educational Resources Information Center

Stephens, Susan A.; Lakin, K. Charlie

This document, the fourth of five volumes of a study of programs of instruction for handicapped children and youth in separate day and residential facilities throughout the United States, contains instruments and materials used in two surveys designed to gather data for the study: (1) a survey of separate facilities; and (2) a survey of State…

Environmental Monitoring Instrumentation and Monitoring Techniques for Space Shuttle Launches.

DTIC Science & Technology

1983-07-01

Monitoring Instrumentation 32 1. Chemiluminescence HCl 32 2. Passive Dosimeter 34 3. Piezoelectric Quartz Crystal Microbalance 34 iJ ,- r, T , .{ , , : , Z...Sensing for STS Launohes 44 IV. SUISIAiR AND CONCLUSIONS 45 V. IBCOIMXIONS 47 References 49 Appendix A - Dosimeter Tube Monitoring Results 52 B - TenaxR...Monitoring Results 6 3 Summary of GBOMET HCI Data for the Launches of STS-i through 8 STS-5 at KSC 4 Dosimeter Tube Inlet Configuration Comparison 14 5 pH

Plasma and cerebrospinal fluid pharmacokinetic parameters after single-dose administration of intravenous, oral, or rectal acetaminophen.

PubMed

Singla, Neil K; Parulan, Cherri; Samson, Roselle; Hutchinson, Joel; Bushnell, Rick; Beja, Evelyn G; Ang, Robert; Royal, Mike A

2012-09-01

This is the first study to compare plasma and cerebrospinal fluid (CSF) pharmacokinetics of intravenous (IV), oral (PO), or rectal (PR) formulations of acetaminophen. Healthy male subjects (N = 6) were randomized to receive a single dose of IV (OFIRMEV(®) ; Cadence) 1,000 mg (15 minute infusion), PO (2 Tylenol(®) 500 mg caplets; McNeil Consumer Healthcare), or PR acetaminophen (2 Feverall(®) 650 mg suppositories; Actavis) with a 1-day washout period between doses. The 1,300 mg PR concentrations were standardized to 1,000 mg. Acetaminophen plasma and CSF levels were obtained at T0, 0.25, 0.5, 0.75, 1, 2, 3, 4, and 6 hours. IV acetaminophen showed earlier and higher plasma and CSF levels compared with PO or PR administration. CSF bioavailability over 6 hours (AUC(0-6)) for IV, PO, and PR 1 g was 24.9, 14.2, and 10.3 μg·h/mL, respectively. No treatment-related adverse events were reported. One subject was replaced because of premature failure of his lumbar spinal catheter. The mean CSF level in the IV group was similar to plasma from 3 to 4 hours and higher from 4 hours on. Absorption phase, variability in plasma, and CSF were greater in PO and PR groups than variability with IV administration. These results demonstrate that earlier and greater CSF penetration occurs as a result of the earlier and higher plasma peak with IV administration compared with PO or PR. © 2012 Lotus Clinical Research, LLC. Pain Practice © 2012 World Institute of Pain.

77 FR 3810 - New York Life Insurance and Annuity Corporation, et al., Notice of Application

Federal Register 2010, 2011, 2012, 2013, 2014

2012-01-25

... SECURITIES AND EXCHANGE COMMISSION [Release No. IC-29923; File No. 812-13902] New York Life... Act from Section 17(a) of the 1940 Act. Applicants: New York Life Insurance and Annuity Corporation... Annuity Separate Account--IV (``VA IV''), NYLIAC Variable Universal Life Separate Account--I (``VUL I...

The Effect of Childhood Family Size on Fertility in Adulthood: New Evidence From IV Estimation.

PubMed

Cools, Sara; Kaldager Hart, Rannveig

2017-02-01

Although fertility is positively correlated across generations, the causal effect of children's experience with larger sibships on their own fertility in adulthood is poorly understood. With the sex composition of the two firstborn children as an instrumental variable, we estimate the effect of sibship size on adult fertility using high-quality data from Norwegian administrative registers. Our study sample is all firstborns or second-borns during the 1960s in Norwegian families with at least two children (approximately 110,000 men and 104,000 women). An additional sibling has a positive effect on male fertility, mainly causing them to have three children themselves, but has a negative effect on female fertility at the same margin. Investigation into mediators reveals that mothers of girls shift relatively less time from market to family work when an additional child is born. We speculate that this scarcity in parents' time makes girls aware of the strains of life in large families, leading them to limit their own number of children in adulthood.

Do High Consumers of Sugar-Sweetened Beverages Respond Differently to Price Changes? A Finite Mixture IV-Tobit Approach.

PubMed

Etilé, Fabrice; Sharma, Anurag

2015-09-01

This study compares the impact of sugar-sweetened beverages (SSBs) tax between moderate and high consumers in Australia. The key methodological contribution is that price response heterogeneity is identified while controlling for censoring of consumption at zero and endogeneity of expenditure by using a finite mixture instrumental variable Tobit model. The SSB price elasticity estimates show a decreasing trend across increasing consumption quantiles, from -2.3 at the median to -0.2 at the 95th quantile. Although high consumers of SSBs have a less elastic demand for SSBs, their very high consumption levels imply that a tax would achieve higher reduction in consumption and higher health gains. Our results also suggest that an SSB tax would represent a small fiscal burden for consumers whatever their pre-policy level of consumption, and that an excise tax should be preferred to an ad valorem tax. Copyright © 2015 John Wiley & Sons, Ltd.

The relationship between cigarette taxes and child maltreatment.

PubMed

McLaughlin, Michael

2018-05-01

Prior research suggests that income and child maltreatment are related, but questions remain about the specific types of economic factors that affect the risk of maltreatment. The need to understand the role of economics in child welfare is critical, given the significant public health costs of child maltreatment. One factor that has been overlooked is regressive taxation. This study addresses this need by examining whether state-level changes in cigarette tax rates predict changes in state-level child maltreatment rates. The results of both a fixed effects (FE) and a fixed effects instrumental variables (FE-IV) estimator show that increases in state cigarette tax rates are followed by increases in child abuse and neglect. An additional test finds that increases in the sales tax (another tax deemed to be regressive) also predict increases in child maltreatment rates. Taken as a whole, the findings suggest that regressive taxes have a significant effect on the risk of child maltreatment. Copyright © 2018 Elsevier Ltd. All rights reserved.

Causal inference from observational data.

PubMed

Listl, Stefan; Jürges, Hendrik; Watt, Richard G

2016-10-01

Randomized controlled trials have long been considered the 'gold standard' for causal inference in clinical research. In the absence of randomized experiments, identification of reliable intervention points to improve oral health is often perceived as a challenge. But other fields of science, such as social science, have always been challenged by ethical constraints to conducting randomized controlled trials. Methods have been established to make causal inference using observational data, and these methods are becoming increasingly relevant in clinical medicine, health policy and public health research. This study provides an overview of state-of-the-art methods specifically designed for causal inference in observational data, including difference-in-differences (DiD) analyses, instrumental variables (IV), regression discontinuity designs (RDD) and fixed-effects panel data analysis. The described methods may be particularly useful in dental research, not least because of the increasing availability of routinely collected administrative data and electronic health records ('big data'). © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Mothers’ Employment and Health of Low-Income Children

PubMed Central

Gennetian, Lisa; Hill, Heather; Lopoo, Leonard; London, Andrew

2010-01-01

This study examines whether maternal employment affects the health status of low-income, elementary-school-aged children using instrumental variables estimation and experimental data from a welfare-to-work program implemented in the early 1990s. Mother’s report of child health status is predicted as a function of exogenous variation in maternal employment associated with random assignment to the program group. IV estimates show a modest adverse effect of maternal employment on children’s health. Making use of data from another welfare-to-work program we propose that any adverse effect on child health may be tempered by increased family income and access to public health insurance coverage, findings with direct relevance to a number of current policy discussions. In a secondary analysis using fixed effects techniques on longitudinal survey data collected in 1998 and 2001, we find a comparable adverse effect of maternal employment on child health that supports the external validity of our primary result. PMID:20356641

Prevalence of and Risk Factors for Asymptomatic Inflammatory (NIH-IV) Prostatitis in Chinese Men

PubMed Central

Wu, Chunlei; Zhang, Zhifu; Lu, Zheng; Liao, Ming; Zhang, Youjie; Xie, Yuanliang; Guo, Xuefeng; Yu, Xiaoxiang; Yang, Xiaobo; Gao, Yong; Tan, Aihua; Mo, Zengnan

2013-01-01

Background While many investigators have studied symptomatic prostatitis, little research has been done with regard to asymptomatic (NIH-IV) prostatitis. Purpose To describe the prevalence of and risk factors for NIH-IV prostatitis among a large male population. Methods The study population was comprised of 1,868 men at the second phase recruitment of a population-based cohort in China. Asymptomatic and symptomatic men were defined by the National Institutes of Health Chronic Prostatitis (CP) Symptom Index. Meanwhile, EPS specimens and their leukocyte count were collected. Lifestyle and demographic characteristics were obtained through a questionnaire. Results Prevalence of NIH-IV prostatitis was 21.1% among 1,868 asymptomatic men aged 19–78 years and increased with age. After adjusteing for potential confounding variables (age, smoking habits, alcohol drinking habits, education, physical activity, hypertension, dyslipidemia, obesity and diabetes), age remained a significant factor for NIH-IV prostatitis (OR = 1.35; 95% CI = 1.06–1.71; P = 0.01) and the risk of NIH-IV prostatitis was significantly higher in smokers≧15 pack/years than non-smokers (OR = 1.33; 95% CI = 1.01–1.75; P = 0.03). In addition, compared with non-drinkers, the OR of NIH-IV prostatitis in drinkers ≧1 drinks/week was 1.35 (95% CI = 1.03, 1.77, p = 0.02) after adjusting for the other variables above. In addition, having less than a college education may be a risk factor for NIH-IV prostatitis, although a statistically significant difference did not exist in our data (OR = 1.22; 95% CI = 0.97–1.52; P = 0.08). Conclusions Our findings suggest that NIH-IV prostatitis is prevalent in China. Age, smoking, drinking and lower education levels were associated with an increased risk of NIH-IV prostatitis. The prevalence of NIH-IV prostatitis should be taken into account when estimating the total prevalence of CP in future studies. PMID:23967188

Quality appraisal of generic self-reported instruments measuring health-related productivity changes: a systematic review

PubMed Central

2014-01-01

Background Health impairments can result in disability and changed work productivity imposing considerable costs for the employee, employer and society as a whole. A large number of instruments exist to measure health-related productivity changes; however their methodological quality remains unclear. This systematic review critically appraised the measurement properties in generic self-reported instruments that measure health-related productivity changes to recommend appropriate instruments for use in occupational and economic health practice. Methods PubMed, PsycINFO, Econlit and Embase were systematically searched for studies whereof: (i) instruments measured health-related productivity changes; (ii) the aim was to evaluate instrument measurement properties; (iii) instruments were generic; (iv) ratings were self-reported; (v) full-texts were available. Next, methodological quality appraisal was based on COSMIN elements: (i) internal consistency; (ii) reliability; (iii) measurement error; (iv) content validity; (v) structural validity; (vi) hypotheses testing; (vii) cross-cultural validity; (viii) criterion validity; and (ix) responsiveness. Recommendations are based on evidence syntheses. Results This review included 25 articles assessing the reliability, validity and responsiveness of 15 different generic self-reported instruments measuring health-related productivity changes. Most studies evaluated criterion validity, none evaluated cross-cultural validity and information on measurement error is lacking. The Work Limitation Questionnaire (WLQ) was most frequently evaluated with moderate respectively strong positive evidence for content and structural validity and negative evidence for reliability, hypothesis testing and responsiveness. Less frequently evaluated, the Stanford Presenteeism Scale (SPS) showed strong positive evidence for internal consistency and structural validity, and moderate positive evidence for hypotheses testing and criterion validity. The Productivity and Disease Questionnaire (PRODISQ) yielded strong positive evidence for content validity, evidence for other properties is lacking. The other instruments resulted in mostly fair-to-poor quality ratings with limited evidence. Conclusions Decisions based on the content of the instrument, usage purpose, target country and population, and available evidence are recommended. Until high-quality studies are in place to accurately assess the measurement properties of the currently available instruments, the WLQ and, in a Dutch context, the PRODISQ are cautiously preferred based on its strong positive evidence for content validity. Based on its strong positive evidence for internal consistency and structural validity, the SPS is cautiously recommended. PMID:24495301

Econometrics in outcomes research: the use of instrumental variables.

PubMed

Newhouse, J P; McClellan, M

1998-01-01

We describe an econometric technique, instrumental variables, that can be useful in estimating the effectiveness of clinical treatments in situations when a controlled trial has not or cannot be done. This technique relies upon the existence of one or more variables that induce substantial variation in the treatment variable but have no direct effect on the outcome variable of interest. We illustrate the use of the technique with an application to aggressive treatment of acute myocardial infarction in the elderly.

Direct variable cost of the topical treatment of stages III and IV pressure injuries incurred in a public university hospital.

PubMed

Chacon, Julieta M F; Blanes, Leila; Borba, Luis G; Rocha, Luis R M; Ferreira, Lydia M

2017-05-01

to estimate the direct variable costs of the topical treatment of stages III and IV pressure injuries of hospitalized patients in a public university hospital, and assess the correlation between these costs and hospitalization time. Forty patients of both sexes who had been admitted to the São Paulo Hospital, São Paulo, SP, Brazil, from 2011 to 2012, with pressure injuries in the sacral, ischial or trochanteric region were included. The patients had a total of 57 pressure injuries in the selected regions, and the lesions were monitored daily until patient release, transfer or death. The quantities and types of materials, as well as the amount of professional labor time spent on each procedure and each patient were recorded. The unit costs of the materials and the hourly costs of the professional labor were obtained from the hospital's purchasing and human resources departments, respectively. Spearman's correlation coefficient and the Mann-Whitney and Kruskal-Wallis tests were used for the statistical analyses. The mean topical treatment costs for stages III and IV PIs were significantly different (US$ 854.82 versus US$ 1785.35; p = 0.004). The mean topical treatment cost of stages III and IV pressure injuries per patient was US$ 1426.37. The mean daily topical treatment cost per patient was US$ 40.83. There was a significant correlation between hospitalization time and the total costs of labor and materials (p < 0.05). There was no significant difference between hospitalization time periods for stages III and IV pressure injuries (40.80 days and 45.01 days, respectively; p = 0.834). The mean direct variable cost of the topical treatment for stages III and IV pressure injuries per patient in this public university hospital was US$ 1426.37. Copyright © 2016. Published by Elsevier Ltd.

Statistical methods for biodosimetry in the presence of both Berkson and classical measurement error

NASA Astrophysics Data System (ADS)

Miller, Austin

In radiation epidemiology, the true dose received by those exposed cannot be assessed directly. Physical dosimetry uses a deterministic function of the source term, distance and shielding to estimate dose. For the atomic bomb survivors, the physical dosimetry system is well established. The classical measurement errors plaguing the location and shielding inputs to the physical dosimetry system are well known. Adjusting for the associated biases requires an estimate for the classical measurement error variance, for which no data-driven estimate exists. In this case, an instrumental variable solution is the most viable option to overcome the classical measurement error indeterminacy. Biological indicators of dose may serve as instrumental variables. Specification of the biodosimeter dose-response model requires identification of the radiosensitivity variables, for which we develop statistical definitions and variables. More recently, researchers have recognized Berkson error in the dose estimates, introduced by averaging assumptions for many components in the physical dosimetry system. We show that Berkson error induces a bias in the instrumental variable estimate of the dose-response coefficient, and then address the estimation problem. This model is specified by developing an instrumental variable mixed measurement error likelihood function, which is then maximized using a Monte Carlo EM Algorithm. These methods produce dose estimates that incorporate information from both physical and biological indicators of dose, as well as the first instrumental variable based data-driven estimate for the classical measurement error variance.

Taller height as a risk factor for venous thromboembolism: a Mendelian randomization meta-analysis.

PubMed

Roetker, N S; Armasu, S M; Pankow, J S; Lutsey, P L; Tang, W; Rosenberg, M A; Palmer, T M; MacLehose, R F; Heckbert, S R; Cushman, M; de Andrade, M; Folsom, A R

2017-07-01

Essentials Observational data suggest taller people have a higher risk of venous thromboembolism (VTE). We used Mendelian randomization techniques to further explore this association in three studies. Risk of VTE increased by 30-40% for each 10 cm increment in height. Height was more strongly associated with deep vein thrombosis than with pulmonary embolism. Background Taller height is associated with a greater risk of venous thromboembolism (VTE). Objectives To use instrumental variable (IV) techniques (Mendelian randomization) to further explore this relationship. Methods Participants of European ancestry were included from two cohort studies (Atherosclerosis Risk in Communities [ARIC] study and Cardiovascular Health Study [CHS]) and one case-control study (Mayo Clinic VTE Study [Mayo]). We created two weighted genetic risk scores (GRSs) for height; the full GRS included 668 single-nucleotide polymorphisms (SNPs) from a previously published meta-analysis, and the restricted GRS included a subset of 362 SNPs not associated with weight independently of height. Standard logistic regression and IV models were used to estimate odds ratios (ORs) for VTE per 10-cm increment in height. ORs were pooled across the three studies by the use of inverse variance-weighted random effects meta-analysis. Results Among 9143 ARIC and 3180 CHS participants free of VTE at baseline, there were 367 and 109 incident VTE events. There were 1143 VTE cases and 1292 controls included from Mayo. The pooled ORs from non-IV models and models using the full and restricted GRSs as IVs were 1.27 (95% confidence interval [CI] 1.11-1.46), 1.34 (95% CI 1.04-1.73) and 1.45 (95% CI 1.04-2.01) per 10-cm greater height, respectively. Conclusions Taller height is associated with an increased risk of VTE in adults of European ancestry. Possible explanations for this association, including taller people having a greater venous surface area, a higher number of venous valves, or greater hydrostatic pressure, need to be explored further. © 2017 International Society on Thrombosis and Haemostasis.

Simultaneous detection and analysis of optical and ultraviolet broad emission lines in quasars at z 2.2

NASA Astrophysics Data System (ADS)

Bisogni, S.; di Serego Alighieri, S.; Goldoni, P.; Ho, L. C.; Marconi, A.; Ponti, G.; Risaliti, G.

2017-06-01

We studied the spectra of six z 2.2 quasars obtained with the X-shooter spectrograph at the Very Large Telescope. The redshift of these sources and the X-shooter's spectral coverage allow us to cover the rest of the spectral range 1200-7000 Å for the simultaneous detection of optical and ultraviolet lines emitted by the broad-line region. Simultaneous measurements, avoiding issues related to quasars variability, help us understand the connection between the different broad-line region line profiles generally used as virial estimators of black hole masses in quasars. The goal of this work is to compare the different emission lines for each object to check on the reliability of Hα, Mg II and C iv with respect to Hβ. Hα and Mg II linewidths correlate well with Hβ, while C iv shows a poorer correlation, due to the presence of strong blueshifts and asymmetries in the profile. We compared our sample with the only other two whose spectra were taken with the same instrument and for all examined lines our results are in agreement with the ones obtained with X-shooter at z 1.5-1.7. We finally evaluate C III] as a possible substitute of C iv in the same spectral range and find that its behaviour is more coherent with those of the other lines: we believe that, when a high quality spectrum such as the ones we present is available and a proper modelization with the Fe II and Fe III emissions is performed, it is more appropriate to use this line than that of C iv if not corrected for the contamination by non-virialized components. Based on observations collected at the European Organisation for Astronomical Research in the Southern Hemisphere, Chile, under programme 086.B-0320(A).The reduced spectra (FITS files) are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/603/A1

The Role of Adiposity in Cardiometabolic Traits: A Mendelian Randomization Analysis

PubMed Central

Ploner, Alexander; Fischer, Krista; Horikoshi, Momoko; Sarin, Antti-Pekka; Thorleifsson, Gudmar; Ladenvall, Claes; Kals, Mart; Kuningas, Maris; Draisma, Harmen H. M.; Ried, Janina S.; van Zuydam, Natalie R.; Huikari, Ville; Mangino, Massimo; Sonestedt, Emily; Benyamin, Beben; Nelson, Christopher P.; Rivera, Natalia V.; Kristiansson, Kati; Shen, Huei-yi; Havulinna, Aki S.; Dehghan, Abbas; Donnelly, Louise A.; Kaakinen, Marika; Nuotio, Marja-Liisa; Robertson, Neil; de Bruijn, Renée F. A. G.; Ikram, M. Arfan; Amin, Najaf; Balmforth, Anthony J.; Braund, Peter S.; Doney, Alexander S. F.; Döring, Angela; Elliott, Paul; Esko, Tõnu; Franco, Oscar H.; Gretarsdottir, Solveig; Hartikainen, Anna-Liisa; Heikkilä, Kauko; Herzig, Karl-Heinz; Holm, Hilma; Hottenga, Jouke Jan; Hyppönen, Elina; Illig, Thomas; Isaacs, Aaron; Isomaa, Bo; Karssen, Lennart C.; Kettunen, Johannes; Koenig, Wolfgang; Kuulasmaa, Kari; Laatikainen, Tiina; Laitinen, Jaana; Lindgren, Cecilia; Lyssenko, Valeriya; Läärä, Esa; Rayner, Nigel W.; Männistö, Satu; Pouta, Anneli; Rathmann, Wolfgang; Rivadeneira, Fernando; Ruokonen, Aimo; Savolainen, Markku J.; Sijbrands, Eric J. G.; Small, Kerrin S.; Smit, Jan H.; Steinthorsdottir, Valgerdur; Syvänen, Ann-Christine; Taanila, Anja; Tobin, Martin D.; Uitterlinden, Andre G.; Willems, Sara M.; Willemsen, Gonneke; Witteman, Jacqueline; Perola, Markus; Evans, Alun; Ferrières, Jean; Virtamo, Jarmo; Kee, Frank; Tregouet, David-Alexandre; Arveiler, Dominique; Amouyel, Philippe; Ferrario, Marco M.; Brambilla, Paolo; Hall, Alistair S.; Heath, Andrew C.; Madden, Pamela A. F.; Martin, Nicholas G.; Montgomery, Grant W.; Whitfield, John B.; Jula, Antti; Knekt, Paul; Oostra, Ben; van Duijn, Cornelia M.; Penninx, Brenda W. J. H.; Davey Smith, George; Kaprio, Jaakko; Samani, Nilesh J.; Gieger, Christian; Peters, Annette; Wichmann, H.-Erich; Boomsma, Dorret I.; de Geus, Eco J. C.; Tuomi, TiinaMaija; Power, Chris; Hammond, Christopher J.; Spector, Tim D.; Lind, Lars; Orho-Melander, Marju; Palmer, Colin Neil Alexander; Morris, Andrew D.; Groop, Leif; Järvelin, Marjo-Riitta; Salomaa, Veikko; Vartiainen, Erkki; Hofman, Albert; Ripatti, Samuli; Metspalu, Andres; Thorsteinsdottir, Unnur; Stefansson, Kari; Pedersen, Nancy L.; McCarthy, Mark I.; Ingelsson, Erik; Prokopenko, Inga

2013-01-01

Background The association between adiposity and cardiometabolic traits is well known from epidemiological studies. Whilst the causal relationship is clear for some of these traits, for others it is not. We aimed to determine whether adiposity is causally related to various cardiometabolic traits using the Mendelian randomization approach. Methods and Findings We used the adiposity-associated variant rs9939609 at the FTO locus as an instrumental variable (IV) for body mass index (BMI) in a Mendelian randomization design. Thirty-six population-based studies of individuals of European descent contributed to the analyses. Age- and sex-adjusted regression models were fitted to test for association between (i) rs9939609 and BMI (n = 198,502), (ii) rs9939609 and 24 traits, and (iii) BMI and 24 traits. The causal effect of BMI on the outcome measures was quantified by IV estimators. The estimators were compared to the BMI–trait associations derived from the same individuals. In the IV analysis, we demonstrated novel evidence for a causal relationship between adiposity and incident heart failure (hazard ratio, 1.19 per BMI-unit increase; 95% CI, 1.03–1.39) and replicated earlier reports of a causal association with type 2 diabetes, metabolic syndrome, dyslipidemia, and hypertension (odds ratio for IV estimator, 1.1–1.4; all p<0.05). For quantitative traits, our results provide novel evidence for a causal effect of adiposity on the liver enzymes alanine aminotransferase and gamma-glutamyl transferase and confirm previous reports of a causal effect of adiposity on systolic and diastolic blood pressure, fasting insulin, 2-h post-load glucose from the oral glucose tolerance test, C-reactive protein, triglycerides, and high-density lipoprotein cholesterol levels (all p<0.05). The estimated causal effects were in agreement with traditional observational measures in all instances except for type 2 diabetes, where the causal estimate was larger than the observational estimate (p = 0.001). Conclusions We provide novel evidence for a causal relationship between adiposity and heart failure as well as between adiposity and increased liver enzymes. Please see later in the article for the Editors' Summary PMID:23824655

The effects of designation and volume of neonatal care on mortality and morbidity outcomes of very preterm infants in England: retrospective population-based cohort study

PubMed Central

Watson, S I; Arulampalam, W; Petrou, S; Marlow, N; Morgan, A S; Draper, E S; Santhakumaran, S; Modi, N

2014-01-01

Objective To examine the effects of designation and volume of neonatal care at the hospital of birth on mortality and morbidity outcomes in very preterm infants in a managed clinical network setting. Design A retrospective, population-based analysis of operational clinical data using adjusted logistic regression and instrumental variables (IV) analyses. Setting 165 National Health Service neonatal units in England contributing data to the National Neonatal Research Database at the Neonatal Data Analysis Unit and participating in the Neonatal Economic, Staffing and Clinical Outcomes Project. Participants 20 554 infants born at <33 weeks completed gestation (17 995 born at 27–32 weeks; 2559 born at <27 weeks), admitted to neonatal care and either discharged or died, over the period 1 January 2009–31 December 2011. Intervention Tertiary designation or high-volume neonatal care at the hospital of birth. Outcomes Neonatal mortality, any in-hospital mortality, surgery for necrotising enterocolitis, surgery for retinopathy of prematurity, bronchopulmonary dysplasia and postmenstrual age at discharge. Results Infants born at <33 weeks gestation and admitted to a high-volume neonatal unit at the hospital of birth were at reduced odds of neonatal mortality (IV regression odds ratio (OR) 0.70, 95% CI 0.53 to 0.92) and any in-hospital mortality (IV regression OR 0.68, 95% CI 0.54 to 0.85). The effect of volume on any in-hospital mortality was most acute among infants born at <27 weeks gestation (IV regression OR 0.51, 95% CI 0.33 to 0.79). A negative association between tertiary-level unit designation and mortality was also observed with adjusted logistic regression for infants born at <27 weeks gestation. Conclusions High-volume neonatal care provided at the hospital of birth may protect against in-hospital mortality in very preterm infants. Future developments of neonatal services should promote delivery of very preterm infants at hospitals with high-volume neonatal units. PMID:25001393

The effects of designation and volume of neonatal care on mortality and morbidity outcomes of very preterm infants in England: retrospective population-based cohort study.

PubMed

Watson, S I; Arulampalam, W; Petrou, S; Marlow, N; Morgan, A S; Draper, E S; Santhakumaran, S; Modi, N

2014-07-07

To examine the effects of designation and volume of neonatal care at the hospital of birth on mortality and morbidity outcomes in very preterm infants in a managed clinical network setting. A retrospective, population-based analysis of operational clinical data using adjusted logistic regression and instrumental variables (IV) analyses. 165 National Health Service neonatal units in England contributing data to the National Neonatal Research Database at the Neonatal Data Analysis Unit and participating in the Neonatal Economic, Staffing and Clinical Outcomes Project. 20 554 infants born at <33 weeks completed gestation (17 995 born at 27-32 weeks; 2559 born at <27 weeks), admitted to neonatal care and either discharged or died, over the period 1 January 2009-31 December 2011. Tertiary designation or high-volume neonatal care at the hospital of birth. Neonatal mortality, any in-hospital mortality, surgery for necrotising enterocolitis, surgery for retinopathy of prematurity, bronchopulmonary dysplasia and postmenstrual age at discharge. Infants born at <33 weeks gestation and admitted to a high-volume neonatal unit at the hospital of birth were at reduced odds of neonatal mortality (IV regression odds ratio (OR) 0.70, 95% CI 0.53 to 0.92) and any in-hospital mortality (IV regression OR 0.68, 95% CI 0.54 to 0.85). The effect of volume on any in-hospital mortality was most acute among infants born at <27 weeks gestation (IV regression OR 0.51, 95% CI 0.33 to 0.79). A negative association between tertiary-level unit designation and mortality was also observed with adjusted logistic regression for infants born at <27 weeks gestation. High-volume neonatal care provided at the hospital of birth may protect against in-hospital mortality in very preterm infants. Future developments of neonatal services should promote delivery of very preterm infants at hospitals with high-volume neonatal units. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

R and D program for core instrumentation improvements devoted for French sodium fast reactors

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

Jeannot, J. P.; Rodriguez, G.; Jammes, C.

2011-07-01

Under the framework of French R and D studies for Generation IV reactors and more specifically for sodium-cooled fast reactors (SFR); the CEA, EDF and AREVA have launched a joint coordinated research programme. This paper deals with the R and D sets out to achieve better inspection, maintenance, availability and decommissioning. In particular the instrumentation requirements for core monitoring and detection in the case of accidental events. Requirements mainly involve diversifying the means of protection and improving instrumentation performance in terms of responsiveness and sensitivity. Operation feedback from the Phenix and Superphenix prototype reactors and studies, carried out within themore » scope of the EFR projects, has been used to define the needs for instrumentation enhancement. (authors)« less

Bipolar mixed features - Results from the comparative effectiveness for bipolar disorder (Bipolar CHOICE) study.

PubMed

Tohen, Mauricio; Gold, Alexandra K; Sylvia, Louisa G; Montana, Rebecca E; McElroy, Susan L; Thase, Michael E; Rabideau, Dustin J; Nierenberg, Andrew A; Reilly-Harrington, Noreen A; Friedman, Edward S; Shelton, Richard C; Bowden, Charles L; Singh, Vivek; Deckersbach, Thilo; Ketter, Terence A; Calabrese, Joseph R; Bobo, William V; McInnis, Melvin G

2017-08-01

DSM-5 changed the criteria from DSM-IV for mixed features in mood disorder episodes to include non-overlapping symptoms of depression and hypomania/mania. It is unknown if, by changing these criteria, the same group would qualify for mixed features. We assessed how those meeting DSM-5 criteria for mixed features compare to those meeting DSM-IV criteria. We analyzed data from 482 adult bipolar patients in Bipolar CHOICE, a randomized comparative effectiveness trial. Bipolar diagnoses were confirmed through the MINI International Neuropsychiatric Interview (MINI). Presence and severity of mood symptoms were collected with the Bipolar Inventory of Symptoms Scale (BISS) and linked to DSM-5 and DSM-IV mixed features criteria. Baseline demographics and clinical variables were compared between mood episode groups using ANOVA for continuous variables and chi-square tests for categorical variables. At baseline, the frequency of DSM-IV mixed episodes diagnoses obtained with the MINI was 17% and with the BISS was 20%. Using DSM-5 criteria, 9% of participants met criteria for hypomania/mania with mixed features and 12% met criteria for a depressive episode with mixed features. Symptom severity was also associated with increased mixed features with a high rate of mixed features in patients with mania/hypomania (63.8%) relative to those with depression (8.0%). Data on mixed features were collected at baseline only and thus do not reflect potential patterns in mixed features within this sample across the study duration. The DSM-5 narrower, non-overlapping definition of mixed episodes resulted in fewer patients who met mixed criteria compared to DSM-IV. Copyright © 2017. Published by Elsevier B.V.

The craving withdrawal model for alcoholism: towards the DSM-V. Improving the discriminant validity of alcohol use disorder diagnosis.

PubMed

de Bruijn, Carla; van den Brink, Wim; de Graaf, Ron; Vollebergh, Wilma A M

2005-01-01

To compare the discriminant validity of the DSM-IV and the ICD-10 classification of alcohol use disorders (AUD) with an alternative classification, the craving withdrawal model (CWM). CWM requires craving and withdrawal for the diagnosis of alcohol dependence and raises the alcohol abuse threshold to two DSM-IV AUD criteria. Data were derived from The Netherlands Mental Health Survey and Incidence Study, a large representative sample of the general Dutch population. In the present study, only non-abstinent subjects were included (n=6041). Three diagnostic systems (DSM-IV, ICD-10, and CWM) were compared using the following discriminant variables: alcohol intake, psychiatric comorbidity, functional status, familial alcohol problems, and treatment sought. The year prevalence of CWM alcohol dependence was lower than the prevalence of ICD-10 and DSM-IV dependence (0.3% vs 1.4% and 1.4%). The year prevalence of abuse was similar for CWM and DSM-IV (4.7 and 4.9%), but lower for ICD-10 harmful use (1.7%). DSM-IV resulted in a poor distinction between normality and abuse and ICD-10 resulted in a poor distinction between harmful use and dependence. In contrast, the CWM distinctions between normality and abuse, and between abuse, and dependence were significant for most of the discriminant variables. This study indicates that CWM improves the discriminant validity of AUD diagnoses. The predictive validity of the CWM for alcohol and other substance use disorders remain to be studied.

Selective thoracic surgery in the Lenke type 1A: King III and King IV type curves.

PubMed

Parisini, P; Di Silvestre, M; Lolli, F; Bakaloudis, G

2009-06-01

Pedicle screw fixation enables enhanced three-dimensional correction of spinal deformities and effectively shortens the distal fusion level. However, the choice of distal fusion level is still controversial in single thoracic idiopathic scoliosis with the lumbar compensatory curve not crossing the middle line (Lenke type 1 with modifier A or King type III and IV curves).The authors retrospectively analyzed 31 patients treated by segmental pedicular instrumentation alone, affected by a single thoracic adolescent idiopathic scoliosis with a compensatory lumbar curve not crossing the midline (Lenke 1A), with an average age of 16.3 years (range 10-22 years). The patients with regard to the King classification were also assessed. A statistical analysis was performed to determine whether the two groups (King III, King IV) presented differences concerning the level of the stable vertebra (SV), end vertebra (EV), and neutral vertebra (NV) and were also analyzed the results at follow-up regarding the relationships between the SV, EV, and lowest instrumented vertebra (LIV). The statistical analysis showed a significant difference between the two curve types. In the King III type curve the SV, EV, and NV appeared to be more proximal than those of the King IV type curve and the segments between the SV, EV, and NV appeared to be reduced in King III curves compared with King IV curves. At a follow-up of 3.2 years (range 2.2-5) the thoracic curve showed a correction of 58.4% (from 62.3 degrees to 26.6 degrees ) and compensatory lumbar curve an average spontaneous correction of 52.4% (from 38.1 degrees to 18.1 degrees ).The position of the LIV was shorter than the position of the SV in 30 patients (97%) with an average "salvage" of 2.1 (from 1 to 4) distal fusion levels. Four cases (13%), all affected by a King IV type curve, presented at follow-up an unsatisfactory results due to an "adding on" phenomenon. The statistical analysis confirmed that this phenomenon was correlated with The King IV curve (P = 0.043; Chi-square test) and that the only predictive parameter for its onset was the LIV-SV difference (odds ratio = 0.093; with a confidence interval of 0.008-1): every time that in King IV curve type the LIV was three or more levels shorter than the stable vertebra at follow-up the "adding on" phenomenon was present. The authors conclude that Lenke's type 1 with modifier A includes two kinds of curves, King III and King IV and that the Lenke's type 2 curves and King V with the lumbar curve not crossing the middle line have a similar behavior. Therefore, it is of authors' opinion that "the adding on phenomenon" could be prevented by more rigidly defining K. IV versus K. III curves. In Lenke's 1/2 A-K. IV/V type with the rotation of the first vertebra just below the thoracic lower EV in the same direction as the thoracic curve, and when SV and EV show more than two levels of difference, it is necessary to extend the lower fusion down to L2 or L3 (not more than two levels shorter than the SV). Whereas in Lenke's 1/2 A-K. III/V with the rotation of the first proximal vertebra of lumbar curve in the opposite direction to the thoracic apex and when SV and EV show not more than two level gap differences, the position of the lowest instrumented vertebra can be two or three levels shorter than the stable vertebra with satisfactory postoperative spinal balance. Therefore, the stable vertebra and the rotation of lumbar curve are considered to be a reliable guide for selecting the lower level of fusion.

Influence of Strategy of Learning and Achievement Motivation of Learning Achievement Class VIII Students of State Junior High School in District Blitar

ERIC Educational Resources Information Center

Ayundawati, Dyah; Setyosari, Punaji; Susilo, Herawati; Sihkabuden

2016-01-01

This study aims for know influence of problem-based learning strategies and achievement motivation on learning achievement. The method used in this research is quantitative method. The instrument used in this study is two fold instruments to measure moderator variable (achievement motivation) and instruments to measure the dependent variable (the…

Alcohol and disorientation-related responses. IV, Effects of different alcohol dosages and display illumination tracking performance during vestibular stimulation.

DOT National Transportation Integrated Search

1971-07-01

A previous CAMI laboratory investigation showed that alcohol impairs the ability of men to suppress vestibular nystagmus while visually fixating on a cockpit instrument, thus degrading visual tracking performance (eye-hand coordination) during angula...

14 CFR 121.337 - Protective breathing equipment.

Code of Federal Regulations, 2010 CFR

2010-01-01

... REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Instrument and Equipment Requirements § 121.337... systems other than chemical oxygen generators, there must be a means to allow the crew to readily... fully charged. (iv) For each chemical oxygen generator, the supply system equipment must meet the...

Potential Aquifer Vulnerability in Regions Down-Gradient from Uranium In Situ Recovery (ISR) Sites

EPA Science Inventory

Sandstone-hosted roll-front uranium ore deposits originate when U(VI) dissolved in groundwater is reduced and precipitated as insoluble U(IV) minerals. Groundwater redox geochemistry, aqueous complexation, and solute migration are instrumental in leaching uranium from source rock...

A Meta-Analytic Review of the Relationships Between the Five-Factor Model and DSM-IV-TR Personality Disorders: A Facet Level Analysis

PubMed Central

Samuel, Douglas B.; Widiger, Thomas A.

2008-01-01

Theory and research have suggested that the personality disorders contained within the American Psychiatric Association's Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR) can be understood as maladaptive variants of the personality traits included within the five-factor model (FFM). The current meta-analysis of FFM personality disorder research both replicated and extended the 2004 work of Saulsman and Page (The five-factor model and personality disorder empirical literature: A meta-analytic review. Clinical Psychology Review, 23, 1055-1085) through a facet-level analysis that provides a more specific and nuanced description of each DSM-IV-TR personality disorder. The empirical FFM profiles generated for each personality disorder were generally congruent at the facet level with hypothesized FFM translations of the DSM-IV-TR personality disorders. However, notable exceptions to the hypotheses did occur and even some findings that were consistent with FFM theory could be said to be instrument specific. PMID:18708274

Pore Structure and Fluoride Ion Adsorption Characteristics of Zr (IV) Surface-Immobilized Resin Prepared Using Polystyrene as a Porogen

NASA Astrophysics Data System (ADS)

Mizuki, Hidenobu; Ito, Yudai; Harada, Hisashi; Uezu, Kazuya

Zr(IV) surface-immobilized resins for removal of fluoride ion were prepared by surface template polymerization using polystyrene as a porogen. At polymerization, polystyrene was added in order to increase mesopores (2-50 nm) and macropore (>50 nm) with large macropores (around 300 nm) formed with internal aqueous phase of W⁄O emulsion. The pore structure of Zr(IV) surface-immobilized resins was evaluated by measuring specific surface area, pore volume, and pore size distribution with volumetric adsorption measurement instrument and mercury porosimeter. The adsorption isotherms were well fitted by Langmuir equation. The removal of fluoride was also carried out with column method. Zr(IV) surface-immobilized resins, using 10 g⁄L polystyrene in toluene at polymerization, possessed higher volume of not only mesopores and macropores but also large macropores. Furethermore, by adding the polystyrene with smaller molecular size, the pore volume of mesopores, macropores and large macropores was significantly increased, and the fluoride ion adsorption capacity and the column utilization also increased.

Maternal and infant activity: Analytic approaches for the study of circadian rhythm.

PubMed

Thomas, Karen A; Burr, Robert L; Spieker, Susan

2015-11-01

The study of infant and mother circadian rhythm entails choice of instruments appropriate for use in the home environment as well as selection of analytic approach that characterizes circadian rhythm. While actigraphy monitoring suits the needs of home study, limited studies have examined mother and infant rhythm derived from actigraphy. Among this existing research a variety of analyses have been employed to characterize 24-h rhythm, reducing ability to evaluate and synthesize findings. Few studies have examined the correspondence of mother and infant circadian parameters for the most frequently cited approaches: cosinor, non-parametric circadian rhythm analysis (NPCRA), and autocorrelation function (ACF). The purpose of this research was to examine analytic approaches in the study of mother and infant circadian activity rhythm. Forty-three healthy mother and infant pairs were studied in the home environment over a 72h period at infant age 4, 8, and 12 weeks. Activity was recorded continuously using actigraphy monitors and mothers completed a diary. Parameters of circadian rhythm were generated from cosinor analysis, NPCRA, and ACF. The correlation among measures of rhythm center (cosinor mesor, NPCRA mid level), strength or fit of 24-h period (cosinor magnitude and R(2), NPCRA amplitude and relative amplitude (RA)), phase (cosinor acrophase, NPCRA M10 and L5 midpoint), and rhythm stability and variability (NPCRA interdaily stability (IS) and intradaily variability (IV), ACF) was assessed, and additionally the effect size (eta(2)) for change over time evaluated. Results suggest that cosinor analysis, NPCRA, and autocorrelation provide several comparable parameters of infant and maternal circadian rhythm center, fit, and phase. IS and IV were strongly correlated with the 24-h cycle fit. The circadian parameters analyzed offer separate insight into rhythm and differing effect size for the detection of change over time. Findings inform selection of analysis and circadian parameters in the study of maternal and infant activity rhythm. Copyright © 2015 Elsevier Inc. All rights reserved.

Maternal and infant activity: Analytic approaches for the study of circadian rhythm

PubMed Central

Thomas, Karen A.; Burr, Robert L.; Spieker, Susan

2015-01-01

The study of infant and mother circadian rhythm entails choice of instruments appropriate for use in the home environment as well as selection of analytic approach that characterizes circadian rhythm. While actigraphy monitoring suits the needs of home study, limited studies have examined mother and infant rhythm derived from actigraphy. Among this existing research a variety of analyses have been employed to characterize 24-h rhythm, reducing ability to evaluate and synthesize findings. Few studies have examined the correspondence of mother and infant circadian parameters for the most frequently cited approaches: cosinor, non-parametric circadian rhythm analysis (NPCRA), and autocorrelation function (ACF). The purpose of this research was to examine analytic approaches in the study of mother and infant circadian activity rhythm. Forty-three healthy mother and infant pairs were studied in the home environment over a 72 h period at infant age 4, 8, and 12 weeks. Activity was recorded continuously using actigraphy monitors and mothers completed a diary. Parameters of circadian rhythm were generated from cosinor analysis, NPCRA, and ACF. The correlation among measures of rhythm center (cosinor mesor, NPCRA mid level), strength or fit of 24-h period (cosinor magnitude and R2, NPCRA amplitude and relative amplitude (RA)), phase (cosinor acrophase, NPCRA M10 and L5 midpoint), and rhythm stability and variability (NPCRA interdaily stability (IS) and intradaily variability (IV), ACF) was assessed, and additionally the effect size (eta2) for change over time evaluated. Results suggest that cosinor analysis, NPCRA, and autocorrelation provide several comparable parameters of infant and maternal circadian rhythm center, fit, and phase. IS and IV were strongly correlated with the 24-h cycle fit. The circadian parameters analyzed offer separate insight into rhythm and differing effect size for the detection of change over time. Findings inform selection of analysis and circadian parameters in the study of maternal and infant activity rhythm. PMID:26360916

Assessing the Genetic Predisposition of Education on Myopia: a Mendelian Randomization Study

PubMed Central

Cuellar-Partida, Gabriel; Lu, Yi; Kho, Pik Fang; Hewitt, Alex W.; Wichmann, H.-Erich; Yazar, Seyhan; Stambolian, Dwight; Bailey-Wilson, Joan E.; Wojciechowski, Robert; Wang, Jie Jin; Mitchell, Paul; Mackey, David A.; MacGregor, Stuart

2016-01-01

Myopia is the largest cause of uncorrected visual impairments globally and its recent dramatic increase in the population has made it a major public health problem. In observational studies, educational attainment has been consistently reported to be correlated to myopia. Nonetheless, correlation does not imply causation. Observational studies do not tell us if education causes myopia or if instead there are confounding factors underlying the association. In this work, we use a two-step least squares instrumental-variable (IV) approach to estimate the causal effect of education on refractive error, specifically myopia. We used the results from the educational attainment GWAS from the Social Science Genetic Association Consortium to define a polygenic risk score (PGRS) in three cohorts of late middle age and elderly Caucasian individuals (N=5,649). In a meta-analysis of the three cohorts, using the PGRS as an IV, we estimated that each z-score increase in education (approximately 2 years of education) results in a reduction of 0.92 ± 0.29 diopters (P=1.04×10−3). Our estimate of the effect of education on myopia was higher (P=0.01) than the observed estimate (0.25 ± 0.03 diopters reduction per education z-score [~2 years] increase). This suggests that observational studies may actually underestimate the true effect. Our Mendelian Randomization (MR) analysis provides new evidence for a causal role of educational attainment on refractive error. PMID:26497973

The Relationship of Hypochondriasis to Anxiety, Depressive, and Somatoform Disorders

PubMed Central

Scarella, Timothy M.; Laferton, Johannes A. C.; Ahern, David K.; Fallon, Brian A.; Barsky, Arthur

2015-01-01

Background Though the phenotype of anxiety about medical illness has long been recognized, there continues to be debate as to whether it is a distinct psychiatric disorder and, if so, to which diagnostic category it belongs. Our objective was to investigate the pattern of psychiatric co-morbidity in hypochondriasis and to assess the relationship of health anxiety to anxiety, depressive, and somatoform disorders. Methods Data were collected as part of a clinical trial on treatment methods for hypochondriasis. 194 participants meeting criteria for DSM-IV hypochondriasis were assessed by sociodemographic variables, results of structured diagnostic interviews, and validated instruments for assessing various symptom dimensions of psychopathology. Results The majority of individuals with hypochondriasis had co-morbid psychiatric illness; the mean number of co-morbid diagnoses was 1.4, and 35.1% had hypochondriasis as their only diagnosis. Participants were more likely to have only co-morbid anxiety disorders than only co-morbid depressive or somatoform disorders. Multiple regression analysis of continuous measures of symptoms revealed the strongest correlation of health anxiety with anxiety symptoms, and a weaker correlation with somatoform symptoms; in multiple regression analysis, there was no correlation between health anxiety and depressive symptoms. Conclusion Our findings suggest that the entity of health anxiety (Hypochondriasis in DSM-IV, Illness Anxiety Disorder in DSM-5) is a clinical syndrome distinct from other psychiatric disorders. Analysis of co-morbidity patterns and continuous measures of symptoms suggest its appropriate classification is with anxiety rather than somatoform or mood disorders. PMID:26785798

Assessing the Genetic Predisposition of Education on Myopia: A Mendelian Randomization Study.

PubMed

Cuellar-Partida, Gabriel; Lu, Yi; Kho, Pik Fang; Hewitt, Alex W; Wichmann, H-Erich; Yazar, Seyhan; Stambolian, Dwight; Bailey-Wilson, Joan E; Wojciechowski, Robert; Wang, Jie Jin; Mitchell, Paul; Mackey, David A; MacGregor, Stuart

2016-01-01

Myopia is the largest cause of uncorrected visual impairments globally and its recent dramatic increase in the population has made it a major public health problem. In observational studies, educational attainment has been consistently reported to be correlated to myopia. Nonetheless, correlation does not imply causation. Observational studies do not tell us if education causes myopia or if instead there are confounding factors underlying the association. In this work, we use a two-step least squares instrumental-variable (IV) approach to estimate the causal effect of education on refractive error, specifically myopia. We used the results from the educational attainment GWAS from the Social Science Genetic Association Consortium to define a polygenic risk score (PGRS) in three cohorts of late middle age and elderly Caucasian individuals (N = 5,649). In a meta-analysis of the three cohorts, using the PGRS as an IV, we estimated that each z-score increase in education (approximately 2 years of education) results in a reduction of 0.92 ± 0.29 diopters (P = 1.04 × 10(-3) ). Our estimate of the effect of education on myopia was higher (P = 0.01) than the observed estimate (0.25 ± 0.03 diopters reduction per education z-score [∼2 years] increase). This suggests that observational studies may actually underestimate the true effect. Our Mendelian Randomization (MR) analysis provides new evidence for a causal role of educational attainment on refractive error. © 2015 WILEY PERIODICALS, INC.

Studying deep seafloor processes based on the analysis of Ocean Bottom Seismometer records

NASA Astrophysics Data System (ADS)

Geli, L. B.; Evangelia, B.; Bayrakci, G.; Tary, J. B.; Klingelhoefer, F.

2017-12-01

Ocean Bottom Seismometers (OBSs) are ultra-sensible instruments capable to detect micrometric motions of seafloor sediments. OBSs commonly record Short Duration Events (SDEs) characterized by durations of less than 0.8 s, by frequencies ranging between 4 and 30 Hz, by highly variable amplitudes and by one single wavetrain, e.g. with undistinguishable P and S arrivals. SDEs may occur either on a regular, permanent basis, at a rate of a few hundred times per day; either as swarms of SDEs, occurring over time spans of a few hours. Seafloor sediment motion may result from a large variety of causes, among which four are described here: i) seabottom currents (including tidal currents); ii) bioturbation processes through which living organisms buried within the uppermost centimeters of sediments expel fluids from tiny cavities just below the seafloor; iii) fluid (water or gas) migration processes, possibly triggered by earthquakes shaking the seafloor sediments; iv) marine mammals, such as finback whales, which also produce signals recorded by hydrophones in the water column. Hence, OBSs are powerful tools that could contribute addressing a number of critical challenges in ocean sciences, provided that we can discriminate between the different causes, e.g.: i) the coupling between ocean current and sediment properties; ii) the role of bioturbation processes in global carbon budgets; iii) the amount of methane and carbon dioxide released by earthquakes into the water column; iv) the tracking of marine mammals, etc.

Linkage mapping of a mouse gene, iv, that controls left-right asymmetry of the heart and viscera.

PubMed Central

Brueckner, M; D'Eustachio, P; Horwich, A L

1989-01-01

Inherited single gene defects have been identified in both humans and mice that lead to loss of developmental control over the left-right asymmetry of the heart and viscera. In mice the recessively inherited mutation iv leads to such apparent loss of control over situs: 50% of iv/iv mice exhibit situs inversus and 50% exhibit normal situs. The affected gene product has not been identified in these animals. To study the normal function of iv, we have taken an approach directed to the gene itself. As a first step, we have mapped iv genetically, by examining its segregation in backcrosses with respect to markers defined by restriction fragment length polymorphisms. The iv locus lies 3 centimorgans (cM) from the immunoglobulin heavy-chain constant-region gene complex (Igh-C) on chromosome 12. A multilocus map of the region suggests the gene order centromere-Aat (alpha 1-antitrypsin gene complex)-(11 cM)-iv-(3 cM)-Igh-C-(1 cM)-Igh-V (immunoglobulin heavy-chain variable-region gene complex). Images PMID:2740340

Quantifying measurement uncertainty and spatial variability in the context of model evaluation

NASA Astrophysics Data System (ADS)

Choukulkar, A.; Brewer, A.; Pichugina, Y. L.; Bonin, T.; Banta, R. M.; Sandberg, S.; Weickmann, A. M.; Djalalova, I.; McCaffrey, K.; Bianco, L.; Wilczak, J. M.; Newman, J. F.; Draxl, C.; Lundquist, J. K.; Wharton, S.; Olson, J.; Kenyon, J.; Marquis, M.

2017-12-01

In an effort to improve wind forecasts for the wind energy sector, the Department of Energy and the NOAA funded the second Wind Forecast Improvement Project (WFIP2). As part of the WFIP2 field campaign, a large suite of in-situ and remote sensing instrumentation was deployed to the Columbia River Gorge in Oregon and Washington from October 2015 - March 2017. The array of instrumentation deployed included 915-MHz wind profiling radars, sodars, wind- profiling lidars, and scanning lidars. The role of these instruments was to provide wind measurements at high spatial and temporal resolution for model evaluation and improvement of model physics. To properly determine model errors, the uncertainties in instrument-model comparisons need to be quantified accurately. These uncertainties arise from several factors such as measurement uncertainty, spatial variability, and interpolation of model output to instrument locations, to name a few. In this presentation, we will introduce a formalism to quantify measurement uncertainty and spatial variability. The accuracy of this formalism will be tested using existing datasets such as the eXperimental Planetary boundary layer Instrumentation Assessment (XPIA) campaign. Finally, the uncertainties in wind measurement and the spatial variability estimates from the WFIP2 field campaign will be discussed to understand the challenges involved in model evaluation.

48 CFR 204.7001 - Policy.

Code of Federal Regulations, 2010 CFR

2010-10-01

... the basic PII number unchanged for the life of the instrument unless the conditions in paragraph (c... not in the Government's best interest solely for administrative reasons (e.g., when the supplementary... predecessor contract once issued; and (iv) Shall not evade competition, expand the scope of work, or extend...

THAT INSTRUMENT IS LOUSY! IN SEARCH OF AGREEMENT WHEN USING INSTRUMENTAL VARIABLES ESTIMATION IN SUBSTANCE USE RESEARCH

PubMed Central

Popovici, Ioana

2009-01-01

SUMMARY The primary statistical challenge that must be addressed when using cross-sectional data to estimate the consequences of consuming addictive substances is the likely endogeneity of substance use. While economists are in agreement on the need to consider potential endogeneity bias and the value of instrumental variables estimation, the selection of credible instruments is a topic of heated debate in the field. Rather than attempt to resolve this debate, our paper highlights the diversity of judgments about what constitutes appropriate instruments for substance use based on a comprehensive review of the economics literature since 1990. We then offer recommendations related to the selection of reliable instruments in future studies. PMID:20029936

Planck early results. IV. First assessment of the High Frequency Instrument in-flight performance

NASA Astrophysics Data System (ADS)

Planck HFI Core Team; Ade, P. A. R.; Aghanim, N.; Ansari, R.; Arnaud, M.; Ashdown, M.; Aumont, J.; Banday, A. J.; Bartelmann, M.; Bartlett, J. G.; Battaner, E.; Benabed, K.; Benoît, A.; Bernard, J.-P.; Bersanelli, M.; Bhatia, R.; Bock, J. J.; Bond, J. R.; Borrill, J.; Bouchet, F. R.; Boulanger, F.; Bradshaw, T.; Bréelle, E.; Bucher, M.; Camus, P.; Cardoso, J.-F.; Catalano, A.; Challinor, A.; Chamballu, A.; Charra, J.; Charra, M.; Chary, R.-R.; Chiang, C.; Church, S.; Clements, D. L.; Colombi, S.; Couchot, F.; Coulais, A.; Cressiot, C.; Crill, B. P.; Crook, M.; de Bernardis, P.; Delabrouille, J.; Delouis, J.-M.; Désert, F.-X.; Dolag, K.; Dole, H.; Doré, O.; Douspis, M.; Efstathiou, G.; Eng, P.; Filliard, C.; Forni, O.; Fosalba, P.; Fourmond, J.-J.; Ganga, K.; Giard, M.; Girard, D.; Giraud-Héraud, Y.; Gispert, R.; Górski, K. M.; Gratton, S.; Griffin, M.; Guyot, G.; Haissinski, J.; Harrison, D.; Helou, G.; Henrot-Versillé, S.; Hernández-Monteagudo, C.; Hildebrandt, S. R.; Hills, R.; Hivon, E.; Hobson, M.; Holmes, W. A.; Huffenberger, K. M.; Jaffe, A. H.; Jones, W. C.; Kaplan, J.; Kneissl, R.; Knox, L.; Lagache, G.; Lamarre, J.-M.; Lami, P.; Lange, A. E.; Lasenby, A.; Lavabre, A.; Lawrence, C. R.; Leriche, B.; Leroy, C.; Longval, Y.; Macías-Pérez, J. F.; Maciaszek, T.; MacTavish, C. J.; Maffei, B.; Mandolesi, N.; Mann, R.; Mansoux, B.; Masi, S.; Matsumura, T.; McGehee, P.; Melin, J.-B.; Mercier, C.; Miville-Deschênes, M.-A.; Moneti, A.; Montier, L.; Mortlock, D.; Murphy, A.; Nati, F.; Netterfield, C. B.; Nørgaard-Nielsen, H. U.; North, C.; Noviello, F.; Novikov, D.; Osborne, S.; Paine, C.; Pajot, F.; Patanchon, G.; Peacocke, T.; Pearson, T. J.; Perdereau, O.; Perotto, L.; Piacentini, F.; Piat, M.; Plaszczynski, S.; Pointecouteau, E.; Pons, R.; Ponthieu, N.; Prézeau, G.; Prunet, S.; Puget, J.-L.; Reach, W. T.; Renault, C.; Ristorcelli, I.; Rocha, G.; Rosset, C.; Roudier, G.; Rowan-Robinson, M.; Rusholme, B.; Santos, D.; Savini, G.; Schaefer, B. M.; Shellard, P.; Spencer, L.; Starck, J.-L.; Stassi, P.; Stolyarov, V.; Stompor, R.; Sudiwala, R.; Sunyaev, R.; Sygnet, J.-F.; Tauber, J. A.; Thum, C.; Torre, J.-P.; Touze, F.; Tristram, M.; van Leeuwen, F.; Vibert, L.; Vibert, D.; Wade, L. A.; Wandelt, B. D.; White, S. D. M.; Wiesemeyer, H.; Woodcraft, A.; Yurchenko, V.; Yvon, D.; Zacchei, A.

2011-12-01

The Planck High Frequency Instrument (HFI) is designed to measure the temperature and polarization anisotropies of the cosmic microwave background and Galactic foregrounds in six ~30% bands centered at 100, 143, 217, 353, 545, and 857 GHz at an angular resolution of 10' (100 GHz), 7' (143 GHz), and 5' (217 GHz and higher). HFI has been operating flawlessly since launch on 14 May 2009, with the bolometers reaching 100 mK the first week of July. The settings of the readout electronics, including bolometer bias currents, that optimize HFI's noise performance on orbit are nearly the same as the ones chosen during ground testing. Observations of Mars, Jupiter, and Saturn have confirmed that the optical beams and the time responses of the detection chains are in good agreement with the predictions of physical optics modeling and pre-launch measurements. The Detectors suffer from a high flux of cosmic rays due to historically low levels of solar activity. As a result of the redundancy of Planck's observation strategy, theremoval of a few percent of data contaminated by glitches does not significantly affect the instrumental sensitivity. The cosmic ray flux represents a significant and variable heat load on the sub-Kelvin stage. Temporal variation and the inhomogeneous distribution of the flux results in thermal fluctuations that are a probable source of low frequency noise. The removal of systematic effects in the time ordered data provides a signal with an average noise equivalent power that is 70% of the goal in the 0.6-2.5 Hz range. This is slightly higher than was achieved during the pre-launch characterization but better than predicted in the early phases of the project. The improvement over the goal is a result of the low level of instrumental background loading achieved by the optical and thermal design of the HFI. Corresponding author: J.-M. Lamarre, jean-michel.lamarre@obspm.fr

Network Mendelian randomization: using genetic variants as instrumental variables to investigate mediation in causal pathways

PubMed Central

Burgess, Stephen; Daniel, Rhian M; Butterworth, Adam S; Thompson, Simon G

2015-01-01

Background: Mendelian randomization uses genetic variants, assumed to be instrumental variables for a particular exposure, to estimate the causal effect of that exposure on an outcome. If the instrumental variable criteria are satisfied, the resulting estimator is consistent even in the presence of unmeasured confounding and reverse causation. Methods: We extend the Mendelian randomization paradigm to investigate more complex networks of relationships between variables, in particular where some of the effect of an exposure on the outcome may operate through an intermediate variable (a mediator). If instrumental variables for the exposure and mediator are available, direct and indirect effects of the exposure on the outcome can be estimated, for example using either a regression-based method or structural equation models. The direction of effect between the exposure and a possible mediator can also be assessed. Methods are illustrated in an applied example considering causal relationships between body mass index, C-reactive protein and uric acid. Results: These estimators are consistent in the presence of unmeasured confounding if, in addition to the instrumental variable assumptions, the effects of both the exposure on the mediator and the mediator on the outcome are homogeneous across individuals and linear without interactions. Nevertheless, a simulation study demonstrates that even considerable heterogeneity in these effects does not lead to bias in the estimates. Conclusions: These methods can be used to estimate direct and indirect causal effects in a mediation setting, and have potential for the investigation of more complex networks between multiple interrelated exposures and disease outcomes. PMID:25150977

Multivariate approach in popcorn genotypes using the Ward-MLM strategy: morpho-agronomic analysis and incidence of Fusarium spp.

PubMed

Kurosawa, R N F; do Amaral Junior, A T; Silva, F H L; Dos Santos, A; Vivas, M; Kamphorst, S H; Pena, G F

2017-02-08

The multivariate analyses are useful tools to estimate the genetic variability between accessions. In the breeding programs, the Ward-Modified Location Model (MLM) multivariate method has been a powerful strategy to quantify variability using quantitative and qualitative variables simultaneously. The present study was proposed in view of the dearth of information about popcorn breeding programs under a multivariate approach using the Ward-MLM methodology. The objective of this study was thus to estimate the genetic diversity among 37 genotypes of popcorn aiming to identify divergent groups associated with morpho-agronomic traits and traits related to resistance to Fusarium spp. To this end, 7 qualitative and 17 quantitative variables were analyzed. The experiment was conducted in 2014, at Universidade Estadual do Norte Fluminense, located in Campos dos Goytacazes, RJ, Brazil. The Ward-MLM strategy allowed the identification of four groups as follows: Group I with 10 genotypes, Group II with 11 genotypes, Group III with 9 genotypes, and Group IV with 7 genotypes. Group IV was distant in relation to the other groups, while groups I, II, and III were near. The crosses between genotypes from the other groups with those of group IV allow an exploitation of heterosis. The Ward-MLM strategy provided an appropriate grouping of genotypes; ear weight, ear diameter, and grain yield were the traits that most contributed to the analysis of genetic diversity.

Treating pre-instrumental data as "missing" data: using a tree-ring-based paleoclimate record and imputations to reconstruct streamflow in the Missouri River Basin

NASA Astrophysics Data System (ADS)

Ho, M. W.; Lall, U.; Cook, E. R.

2015-12-01

Advances in paleoclimatology in the past few decades have provided opportunities to expand the temporal perspective of the hydrological and climatological variability across the world. The North American region is particularly fortunate in this respect where a relatively dense network of high resolution paleoclimate proxy records have been assembled. One such network is the annually-resolved Living Blended Drought Atlas (LBDA): a paleoclimate reconstruction of the Palmer Drought Severity Index (PDSI) that covers North America on a 0.5° × 0.5° grid based on tree-ring chronologies. However, the use of the LBDA to assess North American streamflow variability requires a model by which streamflow may be reconstructed. Paleoclimate reconstructions have typically used models that first seek to quantify the relationship between the paleoclimate variable and the environmental variable of interest before extrapolating the relationship back in time. In contrast, the pre-instrumental streamflow is here considered as "missing" data. A method of imputing the "missing" streamflow data, prior to the instrumental record, is applied through multiple imputation using chained equations for streamflow in the Missouri River Basin. In this method, the distribution of the instrumental streamflow and LBDA is used to estimate sets of plausible values for the "missing" streamflow data resulting in a ~600 year-long streamflow reconstruction. Past research into external climate forcings, oceanic-atmospheric variability and its teleconnections, and assessments of rare multi-centennial instrumental records demonstrate that large temporal oscillations in hydrological conditions are unlikely to be captured in most instrumental records. The reconstruction of multi-centennial records of streamflow will enable comprehensive assessments of current and future water resource infrastructure and operations under the existing scope of natural climate variability.

CARMENES. IV: instrument control software

NASA Astrophysics Data System (ADS)

Guàrdia, Josep; Colomé, Josep; Ribas, Ignasi; Hagen, Hans-Jürgen; Morales, Rafael; Abril, Miguel; Galadí-Enríquez, David; Seifert, Walter; Sánchez Carrasco, Miguel A.; Quirrenbach, Andreas; Amado, Pedro J.; Caballero, Jose A.; Mandel, Holger

2012-09-01

The overall purpose of the CARMENES instrument is to perform high-precision measurements of radial velocities of late-type stars with long-term stability. CARMENES will be installed in 2014 at the 3.5 m telescope in the German- Spanish Astronomical Center at Calar Alto observatory (CAHA, Spain) and will be equipped with two spectrographs in the near-infrared and visible windows. The technology involved in such instrument represents a challenge at all levels. The instrument coordination and management is handled by the Instrument Control System (ICS), which is responsible of carrying out the operations of the different subsystems and providing a tool to operate the instrument from low to high user interaction level. The main goal of the ICS and the CARMENES control layer architecture is to maximize the instrument efficiency by reducing time overheads and by operating it in an integrated manner. The ICS implements the CARMENES operational design. A description of the ICS architecture and the application programming interfaces for low- and high-level communication is given. Internet Communications Engine is the technology selected to implement most of the interface protocols.

Validity of Simpson-Angus Scale (SAS) in a naturalistic schizophrenia population.

PubMed

Janno, Sven; Holi, Matti M; Tuisku, Katinka; Wahlbeck, Kristian

2005-03-17

Simpson-Angus Scale (SAS) is an established instrument for neuroleptic-induced parkinsonism (NIP), but its statistical properties have been studied insufficiently. Some shortcomings concerning its content have been suggested as well. According to a recent report, the widely used SAS mean score cut-off value 0.3 of for NIP detection may be too low. Our aim was to evaluate SAS against DSM-IV diagnostic criteria for NIP and objective motor assessment (actometry). Ninety-nine chronic institutionalised schizophrenia patients were evaluated during the same interview by standardised actometric recording and SAS. The diagnosis of NIP was based on DSM-IV criteria. Internal consistency measured by Cronbach's alpha, convergence to actometry and the capacity for NIP case detection were assessed. Cronbach's alpha for the scale was 0.79. SAS discriminated between DSM-IV NIP and non-NIP patients. The actometric findings did not correlate with SAS. ROC-analysis yielded a good case detection power for SAS mean score. The optimal threshold value of SAS mean score was between 0.65 and 0.95, i.e. clearly higher than previously suggested threshold value. We conclude that SAS seems a reliable and valid instrument. The previously commonly used cut-off mean score of 0.3 has been too low resulting in low specificity, and we suggest a new cut-off value of 0.65, whereby specificity could be doubled without loosing sensitivity.

Validity of Simpson-Angus Scale (SAS) in a naturalistic schizophrenia population

PubMed Central

Janno, Sven; Holi, Matti M; Tuisku, Katinka; Wahlbeck, Kristian

2005-01-01

Background Simpson-Angus Scale (SAS) is an established instrument for neuroleptic-induced parkinsonism (NIP), but its statistical properties have been studied insufficiently. Some shortcomings concerning its content have been suggested as well. According to a recent report, the widely used SAS mean score cut-off value 0.3 of for NIP detection may be too low. Our aim was to evaluate SAS against DSM-IV diagnostic criteria for NIP and objective motor assessment (actometry). Methods Ninety-nine chronic institutionalised schizophrenia patients were evaluated during the same interview by standardised actometric recording and SAS. The diagnosis of NIP was based on DSM-IV criteria. Internal consistency measured by Cronbach's α, convergence to actometry and the capacity for NIP case detection were assessed. Results Cronbach's α for the scale was 0.79. SAS discriminated between DSM-IV NIP and non-NIP patients. The actometric findings did not correlate with SAS. ROC-analysis yielded a good case detection power for SAS mean score. The optimal threshold value of SAS mean score was between 0.65 and 0.95, i.e. clearly higher than previously suggested threshold value. Conclusion We conclude that SAS seems a reliable and valid instrument. The previously commonly used cut-off mean score of 0.3 has been too low resulting in low specificity, and we suggest a new cut-off value of 0.65, whereby specificity could be doubled without loosing sensitivity. PMID:15774006

Concordance of DSM-IV Axis I and II diagnoses by personal and informant's interview.

PubMed

Schneider, Barbara; Maurer, Konrad; Sargk, Dieter; Heiskel, Harald; Weber, Bernhard; Frölich, Lutz; Georgi, Klaus; Fritze, Jürgen; Seidler, Andreas

2004-06-30

The validity and reliability of using psychological autopsies to diagnose a psychiatric disorder is a critical issue. Therefore, interrater and test-retest reliability of the Structured Clinical Interview for DSM-IV Axis I and Personality Disorders and the usefulness of these instruments for the psychological autopsy method were investigated. Diagnoses by informant's interview were compared with diagnoses generated by a personal interview of 35 persons. Interrater reliability and test-retest reliability were assessed in 33 and 29 persons, respectively. Chi-square analysis, kappa and intraclass correlation coefficients, and Kendall's tau were used to determine agreement of diagnoses. Kappa coefficients were above 0.84 for substance-related disorders, mood disorders, and anxiety and adjustment disorders, and above 0.65 for Axis II disorders for interrater and test-retest reliability. Agreement by personal and relative's interview generated kappa coefficients above 0.79 for most Axis I and above 0.65 for most personality disorder diagnoses; Kendall's tau for dimensional individual personality disorder scores ranged from 0.22 to 0.72. Despite of a small number of psychiatric disorders in the selected population, the present results provide support for the validity of most diagnoses obtained through the best-estimate method using the Structured Clinical Interview for DSM-IV Axis I and Personality Disorders. This instrument can be recommended as a tool for the psychological autopsy procedure in post-mortem research. Copyright 2004 Elsevier Ireland Ltd.

ON THE CHALLENGING VARIABILITY OF LS IV-14{sup 0}116: PULSATIONAL INSTABILITIES EXCITED BY THE {epsilon}-MECHANISM

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

Miller Bertolami, M. M.; Corsico, A. H.; Althaus, L. G., E-mail: mmiller@fcaglp.unlp.edu.ar

2011-11-01

We investigate the pulsation driving mechanism responsible for the long-period photometric variations observed in LS IV-14{sup 0}116, a subdwarf B star showing a He-enriched atmospheric composition. To this end, we perform detailed nonadiabatic pulsation computations over fully evolutionary post-He-core-flash stellar structure models, appropriate for hot subdwarf stars at evolutionary phases previous to the He-core burning stage. We found that the variability of LS IV-14{sup 0}116 can be attributed to non-radial g-mode pulsations excited by the {epsilon}-mechanism acting in the He-burning shells that appear before the star settles in the He-core burning stage. Even more interestingly, our results show that LSmore » IV-14{sup 0}116 could be the first known pulsating star in which the {epsilon}-mechanism of mode excitation is operating. Last but not the least, we find that the period range of destabilized modes is sensitive to the exact location of the burning shell, something that might help in distinguishing between the different evolutionary scenarios proposed for the formation of this star.« less

Nonparametric methods in actigraphy: An update

PubMed Central

Gonçalves, Bruno S.B.; Cavalcanti, Paula R.A.; Tavares, Gracilene R.; Campos, Tania F.; Araujo, John F.

2014-01-01

Circadian rhythmicity in humans has been well studied using actigraphy, a method of measuring gross motor movement. As actigraphic technology continues to evolve, it is important for data analysis to keep pace with new variables and features. Our objective is to study the behavior of two variables, interdaily stability and intradaily variability, to describe rest activity rhythm. Simulated data and actigraphy data of humans, rats, and marmosets were used in this study. We modified the method of calculation for IV and IS by modifying the time intervals of analysis. For each variable, we calculated the average value (IVm and ISm) results for each time interval. Simulated data showed that (1) synchronization analysis depends on sample size, and (2) fragmentation is independent of the amplitude of the generated noise. We were able to obtain a significant difference in the fragmentation patterns of stroke patients using an IVm variable, while the variable IV60 was not identified. Rhythmic synchronization of activity and rest was significantly higher in young than adults with Parkinson׳s when using the ISM variable; however, this difference was not seen using IS60. We propose an updated format to calculate rhythmic fragmentation, including two additional optional variables. These alternative methods of nonparametric analysis aim to more precisely detect sleep–wake cycle fragmentation and synchronization. PMID:26483921

Community Physician-Guided Long-Term Domiciliary Oxygen Therapy Combined With Conventional Therapy in Stage IV COPD Patients.

PubMed

Bao, Hong; Wang, Jiaman; Zhou, Ding; Han, Zhaoyong; Zhang, Yuan; Su, Ling; Ye, Xiong; Xu, Chunyan; Fu, Meihong; Li, Qinghua

The aim of the study was to explore clinical effect of community physician-guided long-term domiciliary oxygen therapy (LTDOT) on patients with Stage IV chronic obstructive pulmonary disease (COPD). A retrospective study. Fifty-four patients with Stage IV COPD were recruited and randomly divided into two groups (the LTDOT group and the control group). Patients in LTDOT group accepted additional oxygen therapy for more than 15 hours every day with continuous low flow (1-2 L/min) for 3 years. PaO2 (O2 pressure), FEV1/FVC (forced vital capacity), and FEV1% (percentage of forced expiratory volume in 1 second) in the LTDOT group increased significantly after treatment. A significant decrease was observed on the BODE index in the LTDOT group (p < .05) but not in control group (p > .05). Frequencies and costs of hospitalization therapy and emergency medical services were markedly decreased after 3 years of LTDOT. Community physician-guided LTDOT can improve prognosis and reduce the costs for stage IV COPD patients. Rehabilitation nurses can be instrumental in helping patients with stage IV COPD learn principles of LTDOT.

Evaluation of fracture resistance in simulated immature teeth using Resilon and Ribbond as root reinforcements--an in vitro study.

PubMed

Hemalatha, Hiremath; Sandeep, Metgud; Kulkarni, Sadanand; Yakub, Shoeb Sheikh

2009-08-01

To compare the reinforcement and strengthening ability of resilon, gutta-percha, and ribbond in endodontically treated roots of immature teeth. Sixty five freshly extracted human maxillary anterior teeth were prepared with a Peeso no. 6 to simulate immature teeth (Cvek's stage 3 root development). After instrumentation, each root was irrigated with sodium hypochlorite and with ethylene diamino tetra acetic acid to remove the smear layer. To simulate single visit apexification technique a 4-5 mm white Pro Root mineral trioxide aggregate plug was placed apically using schilder carrier. The teeth were divided into three experimental groups and one control group. Group I--control group (root canals instrumented but not filled); Group II--backfilled with thermoplastisized gutta-percha using AH plus sealer; Group III--reinforced with Resilon using epiphany sealer; Group IV--reinforced with Ribbond fibers using Panavia F luting cement. A Universal Testing Machine was used to apply a load, at the level of the lingual cementoenamel junction with a chisel-shaped tip The peak load to fracture was recorded and statistical analysis was completed using student's t-test. Values of peak load to fracture were 1320.8, 1604.88, 1620, and 1851 newtons for Group I to Group IV respectively. The results of student's t-test, revealed no significant difference (P > 0.05,) between Group II and Group III. Comparison between Group IV and Group III and between Group IV and Group II revealed highly significant difference (P > 0.001). Teeth reinforced with Ribbond fibers using Panavia F luting cement showed the highest resistance to fracture. Resilon could not strengthen the roots and showed no statistically significant difference when compared with thermoplastisized gutta-percha in reinforcing immature tooth when tested with universal testing machine in an experimental model of immature tooth.

46 CFR 62.25-20 - Instrumentation, alarms, and centralized stations.

Code of Federal Regulations, 2010 CFR

2010-10-01

... ENGINEERING VITAL SYSTEM AUTOMATION General Requirements for All Automated Vital Systems § 62.25-20... there is no off position. (5) Automation alarms must be separate and independent of the following: (i... with a means to test audible and visual annunciators; (iv) Provide for normal equipment starting and...

The CGE-PLATO Electronic Laboratory Station Structure and Operation.

ERIC Educational Resources Information Center

Neal, J. P.

An electronic laboratory station was designed for student use in learning electronic instrumentation and measurement by means of the computer-guided experimentation (CGE) system. The station features rack-mounted electronic laboratory equipment on a laboratory table adjacent to a PLATO IV terminal. An integrated logic system behind the laboratory…

75 FR 52033 - Rigging Equipment for Material Handling; Extension of the Office of Management and Budget's (OMB...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-08-24

.... Estimated Total Burden Hours: 51,815. Estimated Cost (Operation and Maintenance): $0. IV. Public... desired format, reporting burden (time and costs) is minimal, collection instruments are clearly...; The accuracy of OSHA's estimate of the burden (time and costs) of the information collection...

77 FR 24990 - Marine Terminals and Longshoring Standards; Extension of the Office of Management and Budget's...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-26

.... Estimated Total Burden Hours: 47,398. Estimated Cost (Operation and Maintenance): $0. IV. Public..., reporting burden (time and costs) is minimal, collection instruments are clearly understood, and OSHA's... safety and health hazards associated with marine terminals and longshoring operations. OSHA uses the...

75 FR 65033 - Manlifts; Extension of the Office of Management and Budget's (OMB) Approval of Information...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-21

.... Estimated Cost (Operation and Maintenance): $0. IV. Public Participation--Submission of Comments on This... costs) is minimal, collection instruments are clearly understood, and OSHA's estimate of the information... of OSHA's estimate of the burden (time and costs) of the information collection requirements...

76 FR 36579 - Onsite Consultation Agreements; Extension of the Office of Management and Budget's (OMB) Approval...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-22

.... Estimated Total urden Hours: 222,924. Estimated Cost (Operation and Maintenance): $0. IV. Public... costs) is minimal, collection instruments are clearly understood, and OSHA's estimate of the information... of OSHA's estimate of the burden (time and costs) of the information collection requirements...

A proposed method to estimate premorbid full scale intelligence quotient (FSIQ) for the Canadian Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) using demographic and combined estimation procedures.

PubMed

Schoenberg, Mike R; Lange, Rael T; Saklofske, Donald H

2007-11-01

Establishing a comparison standard in neuropsychological assessment is crucial to determining change in function. There is no available method to estimate premorbid intellectual functioning for the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV). The WISC-IV provided normative data for both American and Canadian children aged 6 to 16 years old. This study developed regression algorithms as a proposed method to estimate full-scale intelligence quotient (FSIQ) for the Canadian WISC-IV. Participants were the Canadian WISC-IV standardization sample (n = 1,100). The sample was randomly divided into two groups (development and validation groups). The development group was used to generate regression algorithms; 1 algorithm only included demographics, and 11 combined demographic variables with WISC-IV subtest raw scores. The algorithms accounted for 18% to 70% of the variance in FSIQ (standard error of estimate, SEE = 8.6 to 14.2). Estimated FSIQ significantly correlated with actual FSIQ (r = .30 to .80), and the majority of individual FSIQ estimates were within +/-10 points of actual FSIQ. The demographic-only algorithm was less accurate than algorithms combining demographic variables with subtest raw scores. The current algorithms yielded accurate estimates of current FSIQ for Canadian individuals aged 6-16 years old. The potential application of the algorithms to estimate premorbid FSIQ is reviewed. While promising, clinical validation of the algorithms in a sample of children and/or adolescents with known neurological dysfunction is needed to establish these algorithms as a premorbid estimation procedure.

Invited Commentary: Using Financial Credits as Instrumental Variables for Estimating the Causal Relationship Between Income and Health.

PubMed

Pega, Frank

2016-05-01

Social epidemiologists are interested in determining the causal relationship between income and health. Natural experiments in which individuals or groups receive income randomly or quasi-randomly from financial credits (e.g., tax credits or cash transfers) are increasingly being analyzed using instrumental variable analysis. For example, in this issue of the Journal, Hamad and Rehkopf (Am J Epidemiol. 2016;183(9):775-784) used an in-work tax credit called the Earned Income Tax Credit as an instrument to estimate the association between income and child development. However, under certain conditions, the use of financial credits as instruments could violate 2 key instrumental variable analytic assumptions. First, some financial credits may directly influence health, for example, through increasing a psychological sense of welfare security. Second, financial credits and health may have several unmeasured common causes, such as politics, other social policies, and the motivation to maximize the credit. If epidemiologists pursue such instrumental variable analyses, using the amount of an unconditional, universal credit that an individual or group has received as the instrument may produce the most conceptually convincing and generalizable evidence. However, other natural income experiments (e.g., lottery winnings) and other methods that allow better adjustment for confounding might be more promising approaches for estimating the causal relationship between income and health. © The Author 2016. Published by Oxford University Press on behalf of the Johns Hopkins Bloomberg School of Public Health. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Understanding bias in relationships between the food environment and diet quality: the Coronary Artery Risk Development in Young Adults (CARDIA) study.

PubMed

Rummo, Pasquale E; Guilkey, David K; Ng, Shu Wen; Meyer, Katie A; Popkin, Barry M; Reis, Jared P; Shikany, James M; Gordon-Larsen, Penny

2017-12-01

The relationship between food environment exposures and diet behaviours is unclear, possibly because the majority of studies ignore potential residual confounding. We used 20 years (1985-1986, 1992-1993 2005-2006) of data from the Coronary Artery Risk Development in Young Adults (CARDIA) study across four US cities (Birmingham, Alabama; Chicago, Illinois; Minneapolis, Minnesota; Oakland, California) and instrumental variables (IV) regression to obtain causal estimates of longitudinal associations between the percentage of neighbourhood food outlets (per total food outlets within 1 km network distance of respondent residence) and an a priori diet quality score, with higher scores indicating higher diet quality. To assess the presence and magnitude of bias related to residual confounding, we compared results from causal models (IV regression) to non-causal models, including ordinary least squares regression, which does not account for residual confounding at all and fixed-effects regression, which only controls for time-invariant unmeasured characteristics. The mean diet quality score across follow-up was 63.4 (SD=12.7). A 10% increase in fast food restaurants (relative to full-service restaurants) was associated with a lower diet quality score over time using IV regression (β=-1.01, 95% CI -1.99 to -0.04); estimates were attenuated using non-causal models. The percentage of neighbourhood convenience and grocery stores (relative to supermarkets) was not associated with diet quality in any model, but estimates from non-causal models were similarly attenuated compared with causal models. Ignoring residual confounding may generate biased estimated effects of neighbourhood food outlets on diet outcomes and may have contributed to weak findings in the food environment literature. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Relationships between lumbar inter-vertebral motion and lordosis in healthy adult males: a cross sectional cohort study.

PubMed

du Rose, Alister; Breen, Alan

2016-03-10

Intervertebral motion impairment is widely thought to be related to chronic back disability, however, the movements of inter-vertebral pairs are not independent of each other and motion may also be related to morphology. Furthermore, maximum intervertebral range of motion (IV-RoMmax) is difficult to measure accurately in living subjects. The purpose of this study was to explore possible relationships between (IV-RoMmax) and lordosis, initial attainment rate and IV-RoMmax at other levels during weight-bearing flexion using quantitative fluoroscopy (QF). Continuous QF motion sequences were recorded during controlled active sagittal flexion of 60° in 18 males (mean age 27.6 SD 4.4) with no history of low back pain in the previous year. IV-RoMmax, lordotic angle, and initial attainment rate at all inter-vertebral levels from L2-S1 were extracted. Relationships between IV-RoMmax and the other variables were explored using correlation coefficients, and simple linear regression was used to determine the effects of any significant relationships. Within and between observer repeatability of IV-RoMmax and initial attainment rate measurements were assessed in a sub-set of ten participants, using the intra-class correlation coefficient (ICC) and standard error of measurement (SEM). QF measurements were highly repeatable, the lowest ICC for IV-RoMmax, being 0.94 (0.80-0.99) and highest SEM (0.76°). For initial attainment rate the lowest ICC was 0.84 (0.49-0.96) and the highest SEM (0.036). The results also demonstrated significant positive and negative correlations between IV-RoMmax and IV-RoMmax at other lumbar levels (r = -0.64-0.65), lordosis (r = -0.52-0.54), and initial attainment rate (r = -0.64-0.73). Simple linear regression analysis of all significant relationships showed that these predict between 28 and 42 % of the variance in IV-RoMmax. This study found weak to moderate effects of individual kinematic variables and lumbar lordosis on IV-RoMmax at other intervertebral levels. These effects, when combined, may be important when such levels are being considered by healthcare professionals as potential sources of pain generation. Multivariate investigations in larger samples are warranted.

Critical evaluation of connectivity-based point of care testing systems of glucose in a hospital environment.

PubMed

Floré, Katelijne M J; Fiers, Tom; Delanghe, Joris R

2008-01-01

In recent years a number of point of care testing (POCT) glucometers were introduced on the market. We investigated the analytical variability (lot-to-lot variation, calibration error, inter-instrument and inter-operator variability) of glucose POCT systems in a university hospital environment and compared these results with the analytical needs required for tight glucose monitoring. The reference hexokinase method was compared to different POCT systems based on glucose oxidase (blood gas instruments) or glucose dehydrogenase (handheld glucometers). Based upon daily internal quality control data, total errors were calculated for the various glucose methods and the analytical variability of the glucometers was estimated. The total error of the glucometers exceeded by far the desirable analytical specifications (based on a biological variability model). Lot-to-lot variation, inter-instrument variation and inter-operator variability contributed approximately equally to total variance. As in a hospital environment, distribution of hematocrit values is broad, converting blood glucose into plasma values using a fixed factor further increases variance. The percentage of outliers exceeded the ISO 15197 criteria in a broad glucose concentration range. Total analytical variation of handheld glucometers is larger than expected. Clinicians should be aware that the variability of glucose measurements obtained by blood gas instruments is lower than results obtained with handheld glucometers on capillary blood.

Comparative Evaluation of Smear Layer and Debris on the Canal Walls prepared with a Combination of Hand and Rotary ProTaper Technique using Scanning Electron Microscope.

PubMed

Kiran, S; Prakash, Sandeep; Siddharth, Pujari R; Saha, Supradip; Geojan, Naiza E; Ramachandran, Mookambika

2016-07-01

The effect of smear layer and debris on the success rate of endodontic treatment has not yet been definitely determined. So the present study was aimed to evaluate the amount of smear layer and debris on the canal walls prepared with a combination of hand and rotary ProTaper technique using NaOCl and ethylenediaminetetraacetic acid (EDTA) alternately as root canal irrigants using scanning electron microscope (SEM). Eighty intact freshly extracted human permanent mandibular premolar teeth were collected and randomly divided equally into four groups. In group I canals were prepared with hand K-Flexofiles; group II with rotary ProTaper instruments; group III with rotary ProTaper instruments and final instrumentation was done with hand K-Flexofile; group IV with rotary ProTaper instruments and final instrumentation was done with RC-Prep and irrigated with 1 mL of normal saline. In all groups canals were irrigated using NaOCl and EDTA alternately. After instrumentation, the teeth were prepared for SEM examination using five-score indices for debris and smear layer at coronal, middle, and apical third levels. Statistical analysis was performed using chi-square test (p < 0.05) and Kruskal-Wallis test (p < 0.05). Statistically significant difference was observed between the groups in cleaning the apical third. Groups I and III showed better canal cleanliness compared to group II. The use of EDTA and NaOCl in group III was more effective in removing debris and smear layer compared to EDTA and normal saline in group IV. Regardless of the instrumentation technique employed and the irrigant used, the cleaning ability decreased in the apical third, resulting in higher debris and smear layer scores compared to coronal and middle third levels. None of the instrumentation techniques in the present study could completely eliminate the smear layer and debris from the canal walls. Instrumentation of the canals with hand files after automated rotary preparation could result in cleaner canal walls. Alternate irrigation with NaOCl and EDTA is effective in the removal of debris and smear layer in the coronal and middle level, but the effectiveness in the apical third is less.

Extreme Ultraviolet Variability Experiment (EVE) Multiple EUV Grating Spectrographs (MEGS): Radiometric Calibrations and Results

NASA Technical Reports Server (NTRS)

Hock, R. A.; Woods, T. N.; Crotser, D.; Eparvier, F. G.; Woodraska, D. L.; Chamberlin, P. C.; Woods, E. C.

2010-01-01

The NASA Solar Dynamics Observatory (SDO), scheduled for launch in early 2010, incorporates a suite of instruments including the Extreme Ultraviolet Variability Experiment (EVE). EVE has multiple instruments including the Multiple Extreme ultraviolet Grating Spectrographs (MEGS) A, B, and P instruments, the Solar Aspect Monitor (SAM), and the Extreme ultraviolet SpectroPhotometer (ESP). The radiometric calibration of EVE, necessary to convert the instrument counts to physical units, was performed at the National Institute of Standards and Technology (NIST) Synchrotron Ultraviolet Radiation Facility (SURF III) located in Gaithersburg, Maryland. This paper presents the results and derived accuracy of this radiometric calibration for the MEGS A, B, P, and SAM instruments, while the calibration of the ESP instrument is addressed by Didkovsky et al. . In addition, solar measurements that were taken on 14 April 2008, during the NASA 36.240 sounding-rocket flight, are shown for the prototype EVE instruments.

Busulfan pharmacokinetics following intravenous and oral dosing regimens in children receiving high-dose myeloablative chemotherapy for high-risk neuroblastoma as part of the HR-NBL-1/SIOPEN trial.

PubMed

Veal, G J; Nguyen, L; Paci, A; Riggi, M; Amiel, M; Valteau-Couanet, D; Brock, P; Ladenstein, R; Vassal, G

2012-11-01

Busulfan is widely used in a neuroblastoma setting, with several studies reporting marked inter-patient variability in busulfan pharmacokinetics and pharmacodynamics. The current study reports on the pharmacokinetics of oral versus intravenous (IV) busulfan in high-risk neuroblastoma patients treated on the European HR-NBL-1/SIOPEN study. Busulfan was administered four times daily for 4 days to children aged 0.7-13.1 years, either orally (1.45-1.55 mg/kg) or by the IV route (0.8-1.2mg/kg according to body weight strata). Blood samples were obtained prior to administration, 2, 4, and 6h after the start of administration on dose 1. Busulfan analysis was carried out by gas chromatography-mass spectrometry and data analysed using a NONMEM population pharmacokinetic approach. Busulfan plasma concentrations obtained from 38 patients receiving IV busulfan and 25 patients receiving oral busulfan, were fitted simultaneously using a one-compartment pharmacokinetic model. Lower variability in drug exposure was observed following IV administration, with a mean busulfan area under the plasma concentration versus time curve (AUC) of 1146 ± 187 μM.min (range 838-1622), as compared to 953 ± 290 μM.min (range 434-1427) following oral busulfan. A total of 87% of children treated with IV busulfan achieved AUC values within the target of 900-1500 μM.min versus 56% of patients following oral busulfan. Busulfan AUC values were significantly higher in HR-NBL-1/SIOPEN trial patients who experienced hepatic toxicity or veno-occlusive disease (VOD) (1177 ± 189 μM.min versus 913 ± 256 μM.min; p=0.0086). Further stratification based on route of administration suggested that the incidence of hepatic toxicity was related to both high busulfan AUC and oral drug administration. The reduced pharmacokinetic variability and improved control of busulfan AUC observed following IV administration support its utility within the ongoing HR-NBL-1/SIOPEN trial. Copyright © 2012 Elsevier Ltd. All rights reserved.

Coverage and parental perceptions of influenza vaccination among parents of children aged 6 to 23 months in Hong Kong

PubMed Central

2013-01-01

Background The impact of influenza on young children can be severe and even fatal. Influenza vaccination (IV) has been shown to be effective in reducing complications of influenza among children. This study investigated the prevalence and factors of IV among children aged 6-23 months in Hong Kong. Methods A sample of 401 Chinese parents of children aged 6-23 months were interviewed at local Maternal and Child Health Centers. Socio-demographic information, variables related to Health Belief Model, including perceptions about the child’s chance of contracting influenza, perceived harm of influenza on children, perceived benefits and side-effects of IV, having received recommendations from health professionals to uptake IV, and IV behaviors of the children were measured. Multivariate analysis was used to examine factors associated with IV behaviors of children. Results Only 9% of the children had ever been vaccinated. Among those parents who had heard of IV (92.0%), substantial proportions perceived that IV could reduce the risk of influenza-induced complications (70.5%), hospitalization (70.5%) and death (65.9%). Relatively few of the participants believed that IV had no side effects (17.1%) and even less had been recommended by health care professionals to uptake IV (10.6%). Results from multivariate analysis showed that physician recommendations were associated with a higher likelihood for IV among younger children, whilst parental perceptions of the side effects of IV was associated with a lower likelihood for IV. Conclusion The prevalence of IV among children aged 6-23 months in Hong Kong was very low. Promotion of IV with the component of physician recommendations and parents’ knowledge about IV safety for this group is warranted. PMID:24171947

Prospective associations of parental smoking, alcohol use, marital status, maternal satisfaction, and parental and childhood body mass index at 6.5 years with later problematic eating attitudes.

PubMed

Wade, K H; Skugarevsky, O; Kramer, M S; Patel, R; Bogdanovich, N; Vilchuck, K; Sergeichick, N; Richmond, R; Palmer, T; Davey Smith, G; Gillman, M; Oken, E; Martin, R M

2014-01-06

Few studies have prospectively investigated whether early-life exposures are associated with pre-adolescent eating attitudes. The objective of this study is to prospectively investigate associations of parental smoking, alcohol use, marital status, measures of maternal satisfaction, self-reported parental body mass index (BMI) and clinically measured childhood BMI, assessed between birth and 6.5 years, with problematic eating attitudes at 11.5 years. Observational cohort analysis nested within the Promotion of Breastfeeding Intervention Trial, a cluster-randomised trial conducted in 31 maternity hospitals and affiliated polyclinics in Belarus. Our primary outcome was a Children's Eating Attitudes Test (ChEAT) score 22.5 (85th percentile), an indicator of problematic eating attitudes. We employed multivariable mixed logistic regression models, which allow inference at the individual level. We also performed instrumental variable (IV) analysis using parents' BMIs as instruments for the child's BMI, to assess whether associations could be explained by residual confounding or reverse causation. Of the 17 046 infants enrolled between 1996 and 1997 across Belarus, 13 751 (80.7%) completed the ChEAT test at 11.5 years. In fully adjusted models, overweight children at age 6.5 years had a 2.14-fold (95% confidence interval (CI): 1.82, 2.52) increased odds of having ChEAT scores 85th percentile at age 11.5 years, and those who were obese had a 3.89-fold (95% CI: 2.95, 5.14) increased odds compared with normal-weight children. Children of mothers or fathers who were themselves overweight or obese were more likely to score 85th percentile (P for trend 0.001). IV analysis was consistent with a child's BMI causally affecting future eating attitudes. There was little evidence that parental smoking, alcohol use, or marital status or maternal satisfaction were associated with eating attitudes. In our large, prospective cohort in Belarus, both parental and childhood overweight and obesity at 6.5 years were associated with pre-adolescent problematic eating attitudes 5 years later.

Testing our scenario of a failed wind in TW Hya

NASA Astrophysics Data System (ADS)

Canizares, Claude

2017-09-01

We recently discovered variability in X-ray indicators of accretion in the CTTS TW Hya. We seek to use this to understand the physics of accretion in our upcoming HST observations. We have been granted 7 HST orbits to monitor the C IV 155 nm doublet in TW Hya, the closest CTTS, to correlate i) the hot wind ii) the cool wind iii) the photometric period iv) the accretion. In existing HETGS data of TW Hya we see variability in emission lines from the accretion shock on the star. However, the densities in Ne IX and O VII indicate that today's shock models are incomplete. A hot wind is the most promising candidate for this missing component.

Unilateral robotic hybrid mini-maze: a novel experimental approach.

PubMed

Moslemi, Mohammad; Rawashdeh, Badi; Meyer, Mark; Nguyen, Duy; Poston, Robert; Gharagozloo, Farid

2016-03-01

A complete Cox maze IV procedure is difficult to accomplish using current endoscopic and minimally invasive techniques. These techniques are hampered by inability to adequately dissect the posterior structures of the heart and place all necessary lesions. We present a novel approach, using robotic technology, that achieves placement of all the lesions of the complete maze procedure. In three cadaveric human models, the technical feasibility of using robotic instruments through the right chest to dissect the posterior structures of the heart and place all Cox maze lesions was performed. The entire posterior aspect of the heart was dissected in the cadaveric model facilitating successful placement of all Cox maze IV lesions with robotic assistance through minimally invasive incisions. The robotic Cox maze IV procedure through the novel right thoracic approach is feasible. This obviates the need for sternotomy and avoids the associated morbidity of the conventional Cox-maze procedure. Copyright © 2015 John Wiley & Sons, Ltd.

The Development of Astronomy and Emergence of Astrophysics in Thailand

NASA Astrophysics Data System (ADS)

Soonthornthum, Boonrucksar

Astronomy was introduced to Siam (present-day Thailand) over 300 years ago during the reign of King Narai, the Great. The first astronomical observatory was built in Loburi province by French missionary-astronomers and various astronomical instruments were brought to Siam at that time. After King Narai died, astronomy was neglected for over 180 years until the reign of King Rama IV when astronomy became more popular. Members of the Royal Family, King Rama IV in particular, were very interested in astronomy and hence became patrons of modern astronomy in Siam. King Rama IV himself made a precise calculation of the time and location of a total solar eclipse which could be observed from Siam on 18 August 1868. However, modern astronomy in Siam did not evolve rapidly at this time, due in part to the slow development of the educational system.

C IV broad absorption line variability in QSO spectra from SDSS surveys

NASA Astrophysics Data System (ADS)

De Cicco, Demetra; Brandt, William N.; Grier, Catherine J.; Paolillo, Maurizio

2017-12-01

Broad absorption lines (BALs) in the spectra of quasi-stellar objects (QSOs) are thought to arise from outflowing winds along our line of sight; winds, in turn, are thought to originate from the accretion disk, in the very surroundings of the central supermassive black hole (SMBH), and they likely affect the accretion process onto the SMBH, as well as galaxy evolution. BALs can exhibit variability on timescales typically ranging from months to years. We analyze such variability and, in particular, BAL disappearance, with the aim of investigating QSO physics and structure. We search for disappearing C IV BALs in the spectra of 1319 QSOs from different programs from the Sloan Digital Sky Survey (SDSS); the analyzed time span covers 0.28-4.9 yr (rest frame), and the source redshifts are in the range 1.68-4.27. This is to date the largest sample ever used for such a study. We find 67 sources (5.1_{-0.6}^{+0.7}% of the sample) with 73 disappearing BALs in total (3.9_{-0.5}^{+0.5}% of the total number of C IV BALs detected; some sources have more than one BAL that disappears). We compare the sample of disappearing BALs to the whole sample of BALs, and investigate the correlation in the variability of multiple troughs in the same spectrum. We also derive estimates of the average lifetime of a BAL trough and of the BAL phase along our line of sight.

Confirmatory Factor Analysis of the Scales for Diagnosing Attention Deficit Hyperactivity Disorder (SCALES)

ERIC Educational Resources Information Center

Ryser, Gail R.; Campbell, Hilary L.; Miller, Brian K.

2010-01-01

The diagnostic criteria for attention deficit hyperactivity disorder have evolved over time with current versions of the "Diagnostic and Statistical Manual", (4th edition), text revision, ("DSM-IV-TR") suggesting that two constellations of symptoms may be present alone or in combination. The SCALES instrument for diagnosing attention deficit…

Aerospace Plane Technology: Research and Development Efforts in Japan and Australia

DTIC Science & Technology

1991-10-01

However, only with the develop- Aerospace Planes ment of better test facility instruments and more trained personnel, together with the renovation and...necessary. Such a rocket booster (the H-IID) would be one of the largest launchers in the world after the Soviet Energia booster and U.S. Titan IV launch

14 CFR Appendix A to Part 129 - Application for Operations Specifications by Foreign Air Carriers

Code of Federal Regulations, 2010 CFR

2010-01-01

.... Operations. State whether the operation proposed is day or night, visual flight rules, instrument flight...). Sec. IV. Communications facilities. List all communication facilities to be used by the applicant in... English language to a degree necessary to enable them to properly communicate with Airport Traffic Control...

75 FR 9953 - Definition and Requirements for a Nationally Recognized Testing Laboratory (NRTL); Extension of...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-03-04

... Cost (Operation and Maintenance): $0. IV. Public Participation--Submission of Comments on This Notice... and costs) is minimal, collection instruments are clearly understood, and OSHA's estimate of the... information is useful; The accuracy of OSHA's estimate of the burden (time and costs) of the information...

77 FR 9703 - Blasting and the Use of Explosives; Extension of the Office of Management and Budget's (OMB...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-02-17

... Burden Hours: 1,294. Estimated Cost (Operation and Maintenance): $400,000. IV. Public Participation..., reporting burden (time and costs) is minimal, collection instruments are clearly understood, and OSHA's... blasting operations to prevent the accidental discharge of electric blasting caps caused by current induced...

76 FR 65217 - Inorganic Arsenic Standard; Extension of the Office of Management and Budget's (OMB) Approval of...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-20

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77 FR 40087 - 1,3-Butadiene Standard; Extension of the Office of Management and Budget's (OMB) Approval of...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-06

.... Estimated Cost (Operation and Maintenance): $105,912. IV. Public Participation--Submission of Comments on..., reporting burden (time and costs) is minimal, collection instruments are clearly understood, and OSHA's... the information is useful; The accuracy of OSHA's estimate of the burden (time and costs) of the...

77 FR 31395 - The Temporary Labor Camps Standard; Extension of the Office of Management and Budget's (OMB...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-05-25

... Hours: 54 hours. Estimated Cost (Operation and Maintenance): $0. IV. Public Participation--Submission of..., reporting burden (time and costs) is minimal, collection instruments are clearly understood, and OSHA's..., including whether the information is useful; The accuracy of OSHA's estimate of the burden (time and costs...

Family Functioning and Parental Bonding During Childhood in Adults Diagnosed With ADHD.

PubMed

Montejo, José E; Durán, Mariona; Del Mar Martínez, María; Hilari, Ainoa; Roncalli, Nicoletta; Vilaregut, Anna; Corrales, Montserrat; Nogueira, Mariana; Casas, Miguel; Linares, Juan Luis; Ramos-Quiroga, J Antoni

2015-08-24

This work assesses family functioning, parental bonding, and the relationship between the two in adults diagnosed with ADHD. The study used a retrospective, ex post facto design and consisted of 100 adult participants, who were distributed into two groups: with and without diagnosis of ADHD. Two family assessment instruments were applied: the Family Adaptability and Cohesion Evaluation Scale short spanish version (FACES-20esp)) and the Parental Bonding Instrument (PBI). The diagnosis of ADHD was done by using a semistructured interview for Diagnostic and Statistical Manual of Mental Disorders (4th ed.; DSM-IV) criteria (Conners' Adult ADHD Diagnostic Interview for DSM-IV [CAADID]). The results showed that higher rigidity and lower emotional connection were significantly associated with ADHD family functioning. Regarding parental bonding, the results showed significant differences only in the care dimension, with the ADHD group reporting lower care than the control group. The results suggest that ADHD families present dysfunctional family functioning with a rigid, separated typology, and parental bonding based on control without affection. © 2015 SAGE Publications.

Distracted driving in elderly and middle-aged drivers.

PubMed

Thompson, Kelsey R; Johnson, Amy M; Emerson, Jamie L; Dawson, Jeffrey D; Boer, Erwin R; Rizzo, Matthew

2012-03-01

Automobile driving is a safety-critical real-world example of multitasking. A variety of roadway and in-vehicle distracter tasks create information processing loads that compete for the neural resources needed to drive safely. Drivers with mind and brain aging may be particularly susceptible to distraction due to waning cognitive resources and control over attention. This study examined distracted driving performance in an instrumented vehicle (IV) in 86 elderly (mean=72.5 years, SD=5.0 years) and 51 middle-aged drivers (mean=53.7 years, SD=9.3 year) under a concurrent auditory-verbal processing load created by the Paced Auditory Serial Addition Task (PASAT). Compared to baseline (no-task) driving performance, distraction was associated with reduced steering control in both groups, with middle-aged drivers showing a greater increase in steering variability. The elderly drove slower and showed decreased speed variability during distraction compared to middle-aged drivers. They also tended to "freeze up", spending significantly more time holding the gas pedal steady, another tactic that may mitigate time pressured integration and control of information, thereby freeing mental resources to maintain situation awareness. While 39% of elderly and 43% of middle-aged drivers committed significantly more driving safety errors during distraction, 28% and 18%, respectively, actually improved, compatible with allocation of attention resources to safety critical tasks under a cognitive load. Copyright © 2011 Elsevier Ltd. All rights reserved.

Distracted Driving in Elderly and Middle-Aged Drivers

PubMed Central

Thompson, Kelsey R.; Johnson, Amy M.; Emerson, Jamie L.; Dawson, Jeffrey D.; Boer, Erwin R.

2011-01-01

Automobile driving is a safety-critical real-world example of multitasking. A variety of roadway and in-vehicle distracter tasks create information processing loads that compete for the neural resources needed to drive safely. Drivers with mind and brain aging may be particularly susceptible to distraction due to waning cognitive resources and control over attention. This study examined distracted driving performance in an instrumented vehicle (IV) in 86 elderly (mean = 72.5 years, SD = 5.0 years) and 51 middle-aged drivers (mean = 53.7 years, SD = 9.3 year) under a concurrent auditory-verbal processing load created by the Paced Auditory Serial Addition Task (PASAT). Compared to baseline (no-task) driving performance, distraction was associated with reduced steering control in both groups, with middle-aged drivers showing a greater increase in steering variability. The elderly drove slower and showed decreased speed variability during distraction compared to middle-aged drivers. They also tended to “freeze up”, spending significantly more time holding the gas pedal steady, another tactic that may mitigate time pressured integration and control of information, thereby freeing mental resources to maintain situation awareness. While 39% of elderly and 43% of middle-aged drivers committed significantly more driving safety errors during distraction, 28% and 18%, respectively, actually improved, compatible with allocation of attention resources to safety critical tasks under a cognitive load. PMID:22269561

Beyond the floor effect on the Wechsler Intelligence Scale for Children--4th Ed. (WISC-IV): calculating IQ and Indexes of subjects presenting a floored pattern of results.

PubMed

Orsini, A; Pezzuti, L; Hulbert, S

2015-05-01

It is now widely known that children with severe intellectual disability show a 'floor effect' on the Wechsler scales. This effect emerges because the practice of transforming raw scores into scaled scores eliminates any variability present in participants with low intellectual ability and because intelligence quotient (IQ) scores are limited insofar as they do not measure scores lower than 40. Following Hessl et al.'s results, the present authors propose a method for the computation of the Wechsler Intelligence Scale for Children--4th Ed. (WISC-IV)'s IQ and Indexes in intellectually disabled participants affected by a floored pattern of results. The Italian standardization sample (n = 2200) for the WISC-IV was used. The method presented in this study highlights the limits of the 'floor effect' of the WISC-IV in children with serious intellectual disability who present a profile with weighted scores of 1 in all the subtests despite some variability in the raw scores. Such method eliminates the floor effect of the scale and therefore makes it possible to analyse the strengths and weaknesses of the WISC-IV's Indexes in these participants. The Authors reflect on clinical utility of this method and on the meaning of raw score of 0 on subtest. © 2014 MENCAP and International Association of the Scientific Study of Intellectual and Developmental Disabilities and John Wiley & Sons Ltd.

The Paired Availability Design and Related Instrumental Variable Meta-analyses | Division of Cancer Prevention

Cancer.gov

Stuart G. Baker, 2017 Introduction This software computes meta-analysis and extrapolation estimates for an instrumental variable meta-analysis of randomized trial or before-and-after studies (the latter also known as the paired availability design). The software also checks on the assumptions if sufficient data are available. |

Job demands and job strain as risk factors for employee wellbeing in elderly care: an instrumental-variables analysis.

PubMed

Elovainio, Marko; Heponiemi, Tarja; Kuusio, Hannamaria; Jokela, Markus; Aalto, Anna-Mari; Pekkarinen, Laura; Noro, Anja; Finne-Soveri, Harriet; Kivimäki, Mika; Sinervo, Timo

2015-02-01

The association between psychosocial work environment and employee wellbeing has repeatedly been shown. However, as environmental evaluations have typically been self-reported, the observed associations may be attributable to reporting bias. Applying instrumental-variable regression, we used staffing level (the ratio of staff to residents) as an unconfounded instrument for self-reported job demands and job strain to predict various indicators of wellbeing (perceived stress, psychological distress and sleeping problems) among 1525 registered nurses, practical nurses and nursing assistants working in elderly care wards. In ordinary regression, higher self-reported job demands and job strain were associated with increased risk of perceived stress, psychological distress and sleeping problems. The effect estimates for the associations of these psychosocial factors with perceived stress and psychological distress were greater, but less precisely estimated, in an instrumental-variables analysis which took into account only the variation in self-reported job demands and job strain that was explained by staffing level. No association between psychosocial factors and sleeping problems was observed with the instrumental-variable analysis. These results support a causal interpretation of high self-reported job demands and job strain being risk factors for employee wellbeing. © The Author 2014. Published by Oxford University Press on behalf of the European Public Health Association. All rights reserved.

From BASE-ASIA Toward 7-SEAS: A Satellite-Surface Perspective of Boreal Spring Biomass-Burning Aerosols and Clouds in Southeast Asia

NASA Technical Reports Server (NTRS)

Tsay, Si-Chee; Hsu, N. Christina; Lau, William K.-M.; Li, Can; Gabriel, Philip M.; Ji, Qiang; Holben, Brent N.; Welton, E. Judd; Nguyen, Anh X.; Janjai, Serm;

Reducing Readmissions among Heart Failure Patients Discharged to Home Health Care: Effectiveness of Early and Intensive Nursing Services and Early Physician Follow-Up.

PubMed

Murtaugh, Christopher M; Deb, Partha; Zhu, Carolyn; Peng, Timothy R; Barrón, Yolanda; Shah, Shivani; Moore, Stanley M; Bowles, Kathryn H; Kalman, Jill; Feldman, Penny H; Siu, Albert L

2017-08-01

To compare the effectiveness of two "treatments"-early, intensive home health nursing and physician follow-up within a week-versus less intense and later postacute care in reducing readmissions among heart failure (HF) patients discharged to home health care. National Medicare administrative, claims, and patient assessment data. Patients with a full week of potential exposure to the treatments were followed for 30 days to determine exposure status, 30-day all-cause hospital readmission, other health care use, and mortality. An extension of instrumental variables methods for nonlinear statistical models corrects for nonrandom selection of patients into treatment categories. Our instruments are the index hospital's rate of early aftercare for non-HF patients and hospital discharge day of the week. All hospitalizations for a HF principal diagnosis with discharge to home health care between July 2009 and June 2010 were identified from source files. Neither treatment by itself has a statistically significant effect on hospital readmission. In combination, however, they reduce the probability of readmission by roughly 8 percentage points (p < .001; confidence interval = -12.3, -4.1). Results are robust to changes in implementation of the nonlinear IV estimator, sample, outcome measure, and length of follow-up. Our results call for closer coordination between home health and medical providers in the clinical management of HF patients immediately after hospital discharge. © Health Research and Educational Trust.

International guidelines for the in vivo assessment of skin properties in non-clinical settings: Part 2. transepidermal water loss and skin hydration.

PubMed

du Plessis, Johan; Stefaniak, Aleksandr; Eloff, Fritz; John, Swen; Agner, Tove; Chou, Tzu-Chieh; Nixon, Rosemary; Steiner, Markus; Franken, Anja; Kudla, Irena; Holness, Linn

2013-08-01

There is an emerging perspective that it is not sufficient to just assess skin exposure to physical and chemical stressors in workplaces, but that it is also important to assess the condition, i.e. skin barrier function of the exposed skin at the time of exposure. The workplace environment, representing a non-clinical environment, can be highly variable and difficult to control, thereby presenting unique measurement challenges not typically encountered in clinical settings. An expert working group convened a workshop as part of the 5th International Conference on Occupational and Environmental Exposure of Skin to Chemicals (OEESC) to develop basic guidelines and best practices (based on existing clinical guidelines, published data, and own experiences) for the in vivo measurement of transepidermal water loss (TEWL) and skin hydration in non-clinical settings with specific reference to the workplace as a worst-case scenario. Key elements of these guidelines are: (i) to minimize or recognize, to the extent feasible, the influences of relevant endogenous-, exogenous-, environmental- and measurement/instrumentation-related factors; (ii) to measure TEWL with a closed-chamber type instrument; (iii) report results as a difference or percent change (rather than absolute values); and (iv) accurately report any notable deviations from this guidelines. It is anticipated that these guidelines will promote consistent data reporting, which will facilitate inter-comparison of study results. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

International guidelines for the in vivo assessment of skin properties in non-clinical settings: Part 2. transepidermal water loss and skin hydration

PubMed Central

du Plessis, Johan; Stefaniak, Aleksandr; Eloff, Fritz; John, Swen; Agner, Tove; Chou, Tzu-Chieh; Nixon, Rosemary; Steiner, Markus; Franken, Anja; Kudla, Irena; Holness, Linn

2015-01-01

Background There is an emerging perspective that it is not sufficient to just assess skin exposure to physical and chemical stressors in workplaces, but that it is also important to assess the condition, i.e. skin barrier function of the exposed skin at the time of exposure. The workplace environment, representing a non-clinical environment, can be highly variable and difficult to control, thereby presenting unique measurement challenges not typically encountered in clinical settings. Methods An expert working group convened a workshop as part of the 5th International Conference on Occupational and Environmental Exposure of Skin to Chemicals (OEESC) to develop basic guidelines and best practices (based on existing clinical guidelines, published data, and own experiences) for the in vivo measurement of transepidermal water loss (TEWL) and skin hydration in non-clinical settings with specific reference to the workplace as a worst-case scenario. Results Key elements of these guidelines are: (i) to minimize or recognize, to the extent feasible, the influences of relevant endogenous-, exogenous-, environmental- and measurement/instrumentation-related factors; (ii) to measure TEWL with a closed-chamber type instrument; (iii) report results as a difference or percent change (rather than absolute values); and (iv) accurately report any notable deviations from this guidelines. Conclusion It is anticipated that these guidelines will promote consistent data reporting, which will facilitate inter-comparison of study results. PMID:23331328

TRUMP; transient and steady state temperature distribution. [IBM360,370; CDC7600; FORTRAN IV (95%) and BAL (5%) (IBM); FORTRAN IV (CDC)

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

Elrod, D.C.; Turner, W.D.

TRUMP solves a general nonlinear parabolic partial differential equation describing flow in various kinds of potential fields, such as fields of temperature, pressure, or electricity and magnetism; simultaneously, it will solve two additional equations representing, in thermal problems, heat production by decomposition of two reactants having rate constants with a general Arrhenius temperature dependence. Steady-state and transient flow in one, two, or three dimensions are considered in geometrical configurations having simple or complex shapes and structures. Problem parameters may vary with spatial position, time, or primary dependent variables--temperature, pressure, or field strength. Initial conditions may vary with spatial position, andmore » among the criteria that may be specified for ending a problem are upper and lower limits on the size of the primary dependent variable, upper limits on the problem time or on the number of time-steps or on the computer time, and attainment of steady state.IBM360,370;CDC7600; FORTRAN IV (95%) and BAL (5%) (IBM); FORTRAN IV (CDC); OS/360 (IBM360), OS/370 (IBM370), SCOPE 2.1.5 (CDC7600); As dimensioned, the program requires 400K bytes of storage on an IBM370 and 145,100 (octal) words on a CDC7600.« less

The Relationship of Hypochondriasis to Anxiety, Depressive, and Somatoform Disorders.

PubMed

Scarella, Timothy M; Laferton, Johannes A C; Ahern, David K; Fallon, Brian A; Barsky, Arthur

2016-01-01

Though the phenotype of anxiety about medical illness has long been recognized, there continues to be debate as to whether it is a distinct psychiatric disorder and, if so, to which diagnostic category it belongs. Our objective was to investigate the pattern of psychiatric comorbidity in hypochondriasis (HC) and to assess the relationship of health anxiety to anxiety, depressive, and somatoform disorders. Data were collected as part of a clinical trial on treatment methods for HC. In all, 194 participants meeting criteria for Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV) HC were assessed by sociodemographic variables, results of structured diagnostic interviews, and validated instruments for assessing various symptom dimensions of psychopathology. Most of the individuals with HC had comorbid psychiatric illness; the mean number of comorbid diagnoses was 1.4, and 35.1% had HC as their only diagnosis. Participants were more likely to have only comorbid anxiety disorders than only comorbid depressive or somatoform disorders. Multiple regression analysis of continuous measures of symptoms revealed the strongest correlation of health anxiety with anxiety symptoms, and a weaker correlation with somatoform symptoms; in multiple regression analysis, there was no correlation between health anxiety and depressive symptoms. Our findings suggest that the entity of health anxiety (HC in DSM-IV and illness anxiety disorder in DSM-5) is a clinical syndrome distinct from other psychiatric disorders. Analysis of comorbidity patterns and continuous measures of symptoms suggest that its appropriate classification is with anxiety rather than somatoform or mood disorders. Copyright © 2016 The Academy of Psychosomatic Medicine. Published by Elsevier Inc. All rights reserved.

Effectiveness of a coordinated and tailored return-to-work intervention for sickness absence beneficiaries with mental health problems.

PubMed

Martin, Marie H T; Nielsen, Maj Britt D; Madsen, Ida E H; Petersen, Signe M A; Lange, Theis; Rugulies, Reiner

2013-12-01

Sickness absence and exclusion from the labour market due to mental health problems (MHPs) is a growing concern in many countries. Knowledge about effective return-to-work (RTW) intervention models is still limited, but a multidisciplinary, coordinated and tailored approach has shown promising results in the context of musculoskeletal disorders. The purpose of this study was to assess the effectiveness of this approach as implemented among sickness absence beneficiaries with MHPs. In a quasi-randomised, controlled trial, we assessed the intervention's effect in terms of time to RTW and labour market status after 1 year. We used two different analytical strategies to compare time to RTW between participants receiving the intervention (n = 88) and those receiving conventional case management (n = 80): (1) a traditional multivariable regression analysis controlling for measured confounding, and (2) an instrumental variable (IV) analysis controlling for unmeasured confounding. The two analytical approaches provided similar results in terms of a longer time to RTW among recipients of the intervention (HR = 0.50; 95 % CI 0.34-0.75), although the estimate provided by the IV-analysis was non-significant (HR = 0.70; 95 % CI 0.23-2.12). After 1 year, more recipients of the intervention than of conventional case management were receiving sickness absence benefits (p = 0.031). The intervention delayed RTW compared to conventional case management, after accounting for measured confounding. The delayed RTW may be due to either implementation or program failure, or both. It may also reflect the complexity of retaining employees with mental health problems in the workplace.

Validation of the alcohol use module from a multidimensional prenatal psychosocial risk screening instrument.

PubMed

Harrison, Patricia A; Godecker, Amy; Sidebottom, Abbey C

2012-12-01

The purpose of the study was to validate the Prenatal Risk Overview (PRO) Alcohol use domain against a structured diagnostic interview. The PRO was developed to screen for 13 psychosocial risk factors associated with poor birth outcomes. After clinic staff administered the PRO to prenatal patients, they asked for consent to administration of selected modules of the structured clinical interview for DSM-IV (SCID) by a research assistant. To assess the criterion validity of the PRO, low and moderate/high risk classifications from the alcohol use domain were cross-tabulated with SCID Alcohol Use Disorder variables. The study sample included 744 women. Based on PRO responses, 48.7% reported alcohol use during the 12 months before they learned they were pregnant; 5.4% reported use post pregnancy awareness. The typical quantity consumed pre-pregnancy was four or more drinks per occasion. Based on the SCID, 7.4% met DSM-IV criteria for either Alcohol Abuse or Dependence. Sensitivity and specificity of the PRO for Alcohol Use Disorders were 83.6 and 80.3%, respectively. Negative predictive value was 98.4% and positive predictive value was 25.3%. The results indicate the PRO effectively identified pregnant women with Alcohol Use Disorders. However, prenatal screening must also detect consumption patterns that do not meet diagnostic thresholds but may endanger fetal development. The PRO also identified women who continued to drink after they knew they were pregnant, as well as those whose previous drinking habits put them at risk for resumption of hazardous use.

Effects of education on cognition at older ages: evidence from China's Great Famine.

PubMed

Huang, Wei; Zhou, Yi

2013-12-01

This paper explores whether educational attainment has a cognitive reserve capacity in elder life. Using pilot data from the China Health and Retirement Longitudinal Study (CHARLS), we examined the impact of education on cognitive abilities at old ages. OLS results showed that respondents who completed primary school obtained 18.2 percent higher scores on cognitive tests than those who did not. We then constructed an instrumental variable (IV) by leveraging China's Great Famine of 1959-1961 as a natural experiment to estimate the causal effect of education on cognition. Two-stage least squares (2SLS) results provided sound evidence that completing primary school significantly increases cognition scores, especially in episode memory, by almost 20 percent on average. Moreover, Regression Discontinuity (RD) analysis provides further evidence for the causal interpretation, and shows that the effects are different for the different measures of cognition we explored. Our results also show that the Great Famine can result in long-term health consequences through the pathway of losing educational opportunities other than through the pathway of nutrition deprivation. Copyright © 2013 Elsevier Ltd. All rights reserved.

Income and Child Maltreatment in Unmarried Families: Evidence from the Earned Income Tax Credit.

PubMed

Berger, Lawrence M; Font, Sarah A; Slack, Kristen S; Waldfogel, Jane

2017-12-01

This study estimates the associations of income with both (self-reported) child protective services (CPS) involvement and parenting behaviors that proxy for child abuse and neglect risk among unmarried families. Our primary strategy follows the instrumental variables (IV) approach employed by Dahl and Lochner (2012), which leverages variation between states and over time in the generosity of the total state and federal Earned Income Tax Credit for which a family is eligible to identify exogenous variation in family income. As a robustness check, we also estimate standard OLS regressions (linear probability models), reduced form OLS regressions, and OLS regressions with the inclusion of a control function (each with and without family-specific fixed effects). Our micro-level data are drawn from the Fragile Families and Child Wellbeing Study, a longitudinal birth-cohort of relatively disadvantaged urban children who have been followed from birth to age nine. Results suggest that an exogenous increase in income is associated with reductions in behaviorally-approximated child neglect and CPS involvement, particularly among low-income single-mother families.

Confirmatory factor analysis of the PTSD Checklist and the Clinician-Administered PTSD Scale in disaster workers exposed to the World Trade Center Ground Zero.

PubMed

Palmieri, Patrick A; Weathers, Frank W; Difede, JoAnn; King, Dainel W

2007-05-01

Although posttraumatic stress disorder (PTSD) factor analytic research has yielded little support for the DSM-IV 3-factor model of reexperiencing, avoidance, and hyperarousal symptoms, no clear consensus regarding alternative models has emerged. One possible explanation is differential instrumentation across studies. In the present study, the authors used confirmatory factor analysis to compare a self-report measure, the PTSD Checklist (PCL), and a structured clinical interview, the Clinician-Administered PTSD Scale (CAPS), in 2,960 utility workers exposed to the World Trade Center Ground Zero site. Although two 4-factor models fit adequately for each measure, the latent structure of the PCL was slightly better represented by correlated reexperiencing, avoidance, dysphoria, and hyperarousal factors, whereas that of the CAPS was slightly better represented by correlated reexperiencing, avoidance, emotional numbing, and hyperarousal factors. After accounting for method variance, the model specifying dysphoria as a distinct factor achieved slightly better fit. Patterns of correlations with external variables provided additional support for the dysphoria model. Implications regarding the underlying structure of PTSD are discussed.

Current status of intravenous thrombolysis for acute ischemic stroke in Asia.

PubMed

Sharma, Vijay K; Ng, Kay W P; Venketasubramanian, Narayanaswamy; Saqqur, Maher; Teoh, Hock L; Kaul, Subash; Srivastava, Padma M V; Sergentanis, Theodoris; Suwanwela, Nijasri; Nguyen, Thang H; Lawrence Wong, K S; Chan, Bernard P L

2011-12-01

Data regarding thrombolysis for acute ischemic stroke in Asia are scarce and only a small percentage of patients are thrombolysed. The dose of intravenous tissue plasminogen activator (IV-tPA) in Asia remains controversial. Case-controlled observation studies in Asia included only Japanese patients and suggested the clinical efficacy and safety of low-dose IV-tPA (0.6 mg/kg body weight; max 60 mg) comparable to standard dose (0.9 mg/kg body weight; max. 90 mg). Reduced treatment cost, lower symptomatic intracerebral hemorrhage risk and comparable efficacy encouraged many Asian centers to adopt low-dose or even variable-dose IV-tPA regimens. We evaluated various Asian thrombolysis studies and compared with SITS-MOST registry and NINDS trial. We included the published studies on acute ischemic stroke thrombolysis in Asia. Unadjusted relative risks and 95% Confidence intervals were calculated for each study. Pooled estimates from random effects models were used because the tests for heterogeneity were significant. We found only 18 publications regarding acute ischemic stroke thrombolysis in Asia that included total of 9300 patients. Owing to ethnic differences, stroke severity, small number of cases in individual reports, outcome measures and tPA dose regimes, it is difficult to compare these studies. Functional outcomes were almost similar (to Japanese studies) when lower-dose IV-tPA was used in non-Japanese populations across Asia. Interestingly, with standard dose IV-tPA, considerably better functional outcomes were observed, without increasing symptomatic intracerebral hemorrhage rates. Variable dose regimens of IV-tPA are used across Asia without any reliable or established evidence. Establishing a uniform IV-tPA regimen is essential since the rapid improvements in health-care facilities and public awareness are expected to increase the rates of thrombolysis in Asia. © 2011 The Authors. International Journal of Stroke © 2011 World Stroke Organization.

A review of oral cannabinoids and medical marijuana for the treatment of chemotherapy-induced nausea and vomiting: a focus on pharmacokinetic variability and pharmacodynamics.

PubMed

Badowski, Melissa E

2017-09-01

Oral cannabinoids (i.e., dronabinol, nabilone) containing the active component of marijuana, delta(Δ)9-tetrahydrocannabinol (THC), are available for the treatment of chemotherapy-induced nausea and vomiting (CINV) in patients with cancer who have failed to adequately respond to conventional antiemetic therapy. The aim of this article is to provide an overview of the efficacy, pharmacokinetics (PK), pharmacodynamics (PD), and safety of oral cannabinoids for patients with CINV. A PubMed search of the English-language literature available through 4 January 2017 was conducted to identify relevant articles for inclusion in the review. Oral cannabinoids have been shown to have similar or improved efficacy compared with conventional antiemetics for the resolution of nausea and/or vomiting in patients with cancer. However, oral THC has high PK variability, with variability in oral dronabinol peak plasma concentrations (C max ) estimated between 150 and 200%. A new oral dronabinol solution has decreased intraindividual variability (area under the curve) vs oral dronabinol capsules. Further, oral THC has a slower time to C max compared with THC administered intravenously (IV) or by smoking, and a lower systemic availability than IV or smoked THC. The PD profile (e.g., "high") of oral THC differs from that of IV or smoked THC in healthy individuals. Oral cannabinoids are associated with greater incidence of adverse effects compared with conventional antiemetic therapy or placebo (e.g., dizziness, hypotension, and dysphoria or depression). A new formulation of oral cannabinoids (i.e., dronabinol oral solution) minimized the PK/PD variability currently observed with capsule formulations.

Hypoglycemia in noncritically ill patients receiving total parenteral nutrition: a multicenter study. (Study group on the problem of hyperglycemia in parenteral nutrition; Nutrition area of the Spanish Society of Endocrinology and Nutrition).

PubMed

Olveira, Gabriel; Tapia, María José; Ocón, Julia; Cabrejas-Gómez, Carmen; Ballesteros-Pomar, María D; Vidal-Casariego, Alfonso; Arraiza-Irigoyen, Carmen; Olivares, Josefina; Conde-García, Maria Carmen; García-Manzanares, Álvaro; Botella-Romero, Francisco; Quílez-Toboso, Rosa P; Matía, Pilar; Rubio, Miguel Ángel; Chicharro, Luisa; Burgos, Rosa; Pujante, Pedro; Ferrer, Mercedes; Zugasti, Ana; Petrina, Estrella; Manjón, Laura; Diéguez, Marta; Carrera, Ma José; Vila-Bundo, Anna; Urgelés, Juan Ramón; Aragón-Valera, Carmen; Sánchez-Vilar, Olga; Bretón, Irene; García-Peris, Pilar; Muñoz-Garach, Araceli; Márquez, Efren; Del Olmo, Dolores; Pereira, José Luis; Tous, María C

2015-01-01

Hypoglycemia is a common problem among hospitalized patients. Treatment of hyperglycemia with insulin is potentially associated with an increased risk for hypoglycemia. The aim of this study was to determine the prevalence and predictors of hypoglycemia (capillary blood glucose <70 mg/dL) in hospitalized patients receiving total parenteral nutrition (TPN). This prospective multicenter study involved 19 Spanish hospitals. Noncritically ill adults who were prescribed TPN were included, thus enabling us to collect data on capillary blood glucose and insulin dosage. The study included 605 patients of whom 6.8% (n = 41) had at least one capillary blood glucose <70 mg/dL and 2.6% (n = 16) had symptomatic hypoglycemia. The total number of hypoglycemic episodes per 100 d of TPN was 0.82. In univariate analysis, hypoglycemia was significantly associated with the presence of diabetes, a lower body mass index (BMI), and treatment with intravenous (IV) insulin. Patients with hypoglycemia also had a significantly longer hospital length of stay, PN duration, higher blood glucose variability, and a higher insulin dose. Multiple logistic regression analysis showed that a lower BMI, high blood glucose variability, and TPN duration were risk factors for hypoglycemia. Use of IV insulin and blood glucose variability were predictors of symptomatic hypoglycemia. The occurrence of hypoglycemia in noncritically ill patients receiving PN is low. A lower BMI and a greater blood glucose variability and TPN duration are factors associated with the risk for hypoglycemia. IV insulin and glucose variability were predictors of symptomatic hypoglycemia. Copyright © 2015 Elsevier Inc. All rights reserved.

Use of a handheld low-cost sensor to explore the effect of urban design features on local-scale spatial and temporal air quality variability.

PubMed

Miskell, Georgia; Salmond, Jennifer A; Williams, David E

2018-04-01

Portable low-cost instruments have been validated and used to measure ambient nitrogen dioxide (NO 2 ) at multiple sites over a small urban area with 20min time resolution. We use these results combined with land use regression (LUR) and rank correlation methods to explore the effects of traffic, urban design features, and local meteorology and atmosphere chemistry on small-scale spatio-temporal variations. We measured NO 2 at 45 sites around the downtown area of Vancouver, BC, in spring 2016, and constructed four different models: i) a model based on averaging concentrations observed at each site over the whole measurement period, and separate temporal models for ii) morning, iii) midday, and iv) afternoon. Redesign of the temporal models using the average model predictors as constants gave three 'hybrid' models that used both spatial and temporal variables. These accounted for approximately 50% of the total variation with mean absolute error±5ppb. Ranking sites by concentration and by change in concentration across the day showed a shift of high NO 2 concentrations across the central city from morning to afternoon. Locations could be identified in which NO 2 concentration was determined by the geography of the site, and others as ones in which the concentration changed markedly from morning to afternoon indicating the importance of temporal controls. Rank correlation results complemented LUR in identifying significant urban design variables that impacted NO 2 concentration. High variability across a relatively small space was partially described by predictor variables related to traffic (bus stop density, speed limits, traffic counts, distance to traffic lights), atmospheric chemistry (ozone, dew point), and environment (land use, trees). A high-density network recording continuously would be needed fully to capture local variations. Copyright © 2017 Elsevier B.V. All rights reserved.

Assessment of Semi-Structured Clinical Interview for Mobile Phone Addiction Disorder.

PubMed

Alavi, Seyyed Salman; Mohammadi, Mohammad Reza; Jannatifard, Fereshteh; Mohammadi Kalhori, Soroush; Sepahbodi, Ghazal; BabaReisi, Mohammad; Sajedi, Sahar; Farshchi, Mojtaba; KhodaKarami, Rasul; Hatami Kasvaee, Vahid

2016-04-01

The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) classified mobile phone addiction disorder under "impulse control disorder not elsewhere classified". This study surveyed the diagnostic criteria of DSM-IV-TR for the diagnosis of mobile phone addiction in correspondence with Iranian society and culture. Two hundred fifty students of Tehran universities were entered into this descriptive-analytical and cross-sectional study. Quota sampling method was used. At first, semi- structured clinical interview (based on DSM-IV-TR) was performed for all the cases, and another specialist reevaluated the interviews. Data were analyzed using content validity, inter-scorer reliability (Kappa coefficient) and test-retest via SPSS18 software. The content validity of the semi- structured clinical interview matched the DSM-IV-TR criteria for behavioral addiction. Moreover, their content was appropriate, and two items, including "SMS pathological use" and "High monthly cost of using the mobile phone" were added to promote its validity. Internal reliability (Kappa) and test-retest reliability were 0.55 and r = 0.4 (p<0. 01) respectively. The results of this study revealed that semi- structured diagnostic criteria of DSM-IV-TR are valid and reliable for diagnosing mobile phone addiction, and this instrument is an effective tool to diagnose this disorder.

The 10/66 Dementia Research Group's fully operationalised DSM-IV dementia computerized diagnostic algorithm, compared with the 10/66 dementia algorithm and a clinician diagnosis: a population validation study

PubMed Central

Prince, Martin J; de Rodriguez, Juan Llibre; Noriega, L; Lopez, A; Acosta, Daisy; Albanese, Emiliano; Arizaga, Raul; Copeland, John RM; Dewey, Michael; Ferri, Cleusa P; Guerra, Mariella; Huang, Yueqin; Jacob, KS; Krishnamoorthy, ES; McKeigue, Paul; Sousa, Renata; Stewart, Robert J; Salas, Aquiles; Sosa, Ana Luisa; Uwakwa, Richard

2008-01-01

Background The criterion for dementia implicit in DSM-IV is widely used in research but not fully operationalised. The 10/66 Dementia Research Group sought to do this using assessments from their one phase dementia diagnostic research interview, and to validate the resulting algorithm in a population-based study in Cuba. Methods The criterion was operationalised as a computerised algorithm, applying clinical principles, based upon the 10/66 cognitive tests, clinical interview and informant reports; the Community Screening Instrument for Dementia, the CERAD 10 word list learning and animal naming tests, the Geriatric Mental State, and the History and Aetiology Schedule – Dementia Diagnosis and Subtype. This was validated in Cuba against a local clinician DSM-IV diagnosis and the 10/66 dementia diagnosis (originally calibrated probabilistically against clinician DSM-IV diagnoses in the 10/66 pilot study). Results The DSM-IV sub-criteria were plausibly distributed among clinically diagnosed dementia cases and controls. The clinician diagnoses agreed better with 10/66 dementia diagnosis than with the more conservative computerized DSM-IV algorithm. The DSM-IV algorithm was particularly likely to miss less severe dementia cases. Those with a 10/66 dementia diagnosis who did not meet the DSM-IV criterion were less cognitively and functionally impaired compared with the DSMIV confirmed cases, but still grossly impaired compared with those free of dementia. Conclusion The DSM-IV criterion, strictly applied, defines a narrow category of unambiguous dementia characterized by marked impairment. It may be specific but incompletely sensitive to clinically relevant cases. The 10/66 dementia diagnosis defines a broader category that may be more sensitive, identifying genuine cases beyond those defined by our DSM-IV algorithm, with relevance to the estimation of the population burden of this disorder. PMID:18577205

Concordance between DSM-5 and DSM-IV nicotine, alcohol, and cannabis use disorder diagnoses among pediatric patients.

PubMed

Kelly, Sharon M; Gryczynski, Jan; Mitchell, Shannon Gwin; Kirk, Arethusa; O'Grady, Kevin E; Schwartz, Robert P

2014-07-01

The recently published Diagnostic and Statistical Manual of Mental Disorders-5 (DSM-5) includes several major revisions to substance use diagnoses. Studies have evaluated the impact of these changes among adult samples but research with adolescent samples is lacking. 525 adolescents (93% African American) awaiting primary care appointments in Baltimore, Maryland were recruited for a study evaluating a substance use screening instrument. Participants were assessed for DSM-5 nicotine, alcohol, and cannabis use disorder, DSM-IV alcohol and cannabis abuse, and DSM-IV dependence for all three substances during the past year using the modified Composite International Diagnostic Interview-2, Substance Abuse Module. Contingency tables examining DSM-5 vs. DSM-IV joint frequency distributions were examined for each substance. Diagnoses were more prevalent using DSM-5 criteria compared with DSM-IV for nicotine (4.0% vs. 2.7%), alcohol (4.6% vs. 3.8%), and cannabis (10.7% vs. 8.2%). Cohen's κ, Somers' d, and Cramer's V ranged from 0.70 to 0.99 for all three substances. Of the adolescents categorized as "diagnostic orphans" under DSM-IV, 7/16 (43.8%), 9/29 (31.0%), and 13/36 (36.1%) met criteria for DSM-5 disorder for nicotine, alcohol, and cannabis, respectively. Additionally, 5/17 (29.4%) and 1/21 (4.8%) adolescents who met criteria for DSM-IV abuse did not meet criteria for a DSM-5 diagnosis for alcohol and cannabis, respectively. Categorizing adolescents using DSM-5 criteria may result in diagnostic net widening-particularly for cannabis use disorders-by capturing adolescents who were considered diagnostic orphans using DSM-IV criteria. Future research examining the validity of DSM-5 substance use disorders with larger and more diverse adolescent samples is needed. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Concordance between DSM-5 and DSM-IV nicotine, alcohol, and cannabis use disorder diagnoses among pediatric patients

PubMed Central

Kelly, Sharon M.; Gryczynski, Jan; Mitchell, Shannon Gwin; Kirk, Arethusa; O’Grady, Kevin E.; Schwartz, Robert P.

2014-01-01

Background The recently published Diagnostic and Statistical Manual of Mental Disorders-5 (DSM-5) includes several major revisions to substance use diagnoses. Studies have evaluated the impact of these changes among adult samples but research with adolescent samples is lacking. Methods 525 adolescents (93% African American) awaiting primary care appointments in Baltimore, Maryland were recruited for a study evaluating a substance use screening instrument. Participants were assessed for DSM-5 nicotine, alcohol, and cannabis use disorder, DSM-IV alcohol and cannabis abuse, and DSM-IV dependence for all three substances during the past year using the modified Composite International Diagnostic Interview-2, Substance Abuse Module. Contingency tables examining DSM-5 vs. DSM-IV joint frequency distributions were examined for each substance. Results Diagnoses were more prevalent using DSM-5 criteria compared with DSM-IV for nicotine (4.0% vs. 2.7%), alcohol (4.6% vs. 3.8%), and cannabis (10.7% vs. 8.2%). Cohen's κ, Somers' d, and Cramer's V ranged from 0.70-0.99 for all three substances. Of the adolescents categorized as “diagnostic orphans” under DSM-IV, 7/16 (43.8%), 9/29 (31.0%), and 13/36 (36.1%) met criteria for DSM-5 disorder for nicotine, alcohol, and cannabis, respectively. Additionally, 5/17 (29.4%) and 1/21 (4.8%) adolescents who met criteria for DSM-IV abuse did not meet criteria for a DSM-5 diagnosis for alcohol and cannabis, respectively. Conclusions Categorizing adolescents using DSM-5 criteria may result in diagnostic net widening-particularly for cannabis use disorders-by capturing adolescents who were considered diagnostic orphans using DSM-IV criteria. Future research examining the validity of DSM-5 substance use disorders with larger and more diverse adolescent samples is needed. PMID:24793367

Prediction of future falls in a community dwelling older adult population using instrumented balance and gait analysis.

PubMed

Bauer, C M; Gröger, I; Rupprecht, R; Marcar, V L; Gaßmann, K G

2016-04-01

The role of instrumented balance and gait assessment when screening for prospective fallers is currently a topic of controversial discussion. This study analyzed the association between variables derived from static posturography, instrumented gait analysis and clinical assessments with the occurrence of prospective falls in a sample of community dwelling older people. In this study 84 older people were analyzed. Based on a prospective occurrence of falls, participants were categorized into fallers and non-fallers. Variables derived from clinical assessments, static posturography and instrumented gait analysis were evaluated with respect to the association with the occurrence of prospective falls using a forward stepwise, binary, logistic regression procedure. Fallers displayed a significantly shorter single support time during walking while counting backwards, increased mediolateral to anteroposterior sway amplitude ratio, increased fast mediolateral oscillations and a larger coefficient (Coeff) of sway direction during various static posturography tests. Previous falls were insignificantly associated with the occurrence of prospective falls. Variables derived from posturography and instrumented gait analysis showed significant associations with the occurrence of prospective falls in a sample of community dwelling older adults.

Robust best linear estimator for Cox regression with instrumental variables in whole cohort and surrogates with additive measurement error in calibration sample

PubMed Central

Wang, Ching-Yun; Song, Xiao

2017-01-01

SUMMARY Biomedical researchers are often interested in estimating the effect of an environmental exposure in relation to a chronic disease endpoint. However, the exposure variable of interest may be measured with errors. In a subset of the whole cohort, a surrogate variable is available for the true unobserved exposure variable. The surrogate variable satisfies an additive measurement error model, but it may not have repeated measurements. The subset in which the surrogate variables are available is called a calibration sample. In addition to the surrogate variables that are available among the subjects in the calibration sample, we consider the situation when there is an instrumental variable available for all study subjects. An instrumental variable is correlated with the unobserved true exposure variable, and hence can be useful in the estimation of the regression coefficients. In this paper, we propose a nonparametric method for Cox regression using the observed data from the whole cohort. The nonparametric estimator is the best linear combination of a nonparametric correction estimator from the calibration sample and the difference of the naive estimators from the calibration sample and the whole cohort. The asymptotic distribution is derived, and the finite sample performance of the proposed estimator is examined via intensive simulation studies. The methods are applied to the Nutritional Biomarkers Study of the Women’s Health Initiative. PMID:27546625

Nonparametric instrumental regression with non-convex constraints

NASA Astrophysics Data System (ADS)

Grasmair, M.; Scherzer, O.; Vanhems, A.

2013-03-01

This paper considers the nonparametric regression model with an additive error that is dependent on the explanatory variables. As is common in empirical studies in epidemiology and economics, it also supposes that valid instrumental variables are observed. A classical example in microeconomics considers the consumer demand function as a function of the price of goods and the income, both variables often considered as endogenous. In this framework, the economic theory also imposes shape restrictions on the demand function, such as integrability conditions. Motivated by this illustration in microeconomics, we study an estimator of a nonparametric constrained regression function using instrumental variables by means of Tikhonov regularization. We derive rates of convergence for the regularized model both in a deterministic and stochastic setting under the assumption that the true regression function satisfies a projected source condition including, because of the non-convexity of the imposed constraints, an additional smallness condition.

Development of Probabilistic Rigid Pavement Design Methodologies for Military Airfields.

DTIC Science & Technology

1983-12-01

4A161102AT22, Task AO, Work Unit 009, "Methodology for Considering Material Variability in Pavement Design." OCE Project Monitor was Mr. S. S. Gillespie. The...PREFACE. .. ............................. VOLUME 1: STATE OF THE ART VARIABILITY OF AIRFIELD PAVEMENT MATERIALS VOLUME 11: MATHEMATICAL FORMULATION OF...VOLUME IV: PROBABILISTIC ANALYSIS OF RIGID AIRFIELD DESIGN BY ELASTIC LAYERED THEORY VOLUME I STATE OF THE ART VARIABILITY OF AIRFIELD PAVEMENT MATERIALS

A search for the cause of cyclical wind variability in O stars. Simultaneous UV and optical observations including magnetic field measurements of the O7.5III star xi Persei

NASA Astrophysics Data System (ADS)

de Jong, J. A.; Henrichs, H. F.; Kaper, L.; Nichols, J. S.; Bjorkman, K.; Bohlender, D. A.; Cao, H.; Gordon, K.; Hill, G.; Jiang, Y.; Kolka, I.; Morrison, N.; Neff, J.; O'Neal, D.; Scheers, B.; Telting, J. H.

2001-03-01

We present the results of an extensive observing campaign on the O7.5 III star xi Persei. The UV observations were obtained with the International Ultraviolet Explorer. xi Per was monitored continuously in October 1994 during 10 days at ultraviolet and visual wavelengths. The ground-based optical observations include magnetic field measurements, Hα and He I lambda 6678 spectra, and were partially covered by photometry and polarimetry. We describe a method to automatically remove the variable contamination of telluric lines in the groundbased spectra. The aim of this campaign was to search for the origin of the cyclical wind variability in this star. We determined a very accurate period of 2.086(2) d in the resonance lines of Si Iv and in the subordinate N Iv and Hα line profiles. The epochs of maximum absorption in the UV resonance lines due to discrete absorption components (DACs) coincide in phase with the maxima in blue-shifted Hα absorption. This implies that the periodic variability originates close to the stellar surface. The phase-velocity relation shows a maximum at -1400 km s-1. The general trend of these observations can be well explained by the corotating interaction region (CIR) model. In this model the wind is perturbed by one or more fixed patches on the stellar surface, which are most probably due to small magnetic field structures. Our magnetic field measurements gave, however, only a null-detection with a 1sigma errorbar of 70 G in the longitudinal component. Some observations are more difficult to fit into this picture. The 2-day period is not detected in the photospheric/transition region line He I lambda 6678. The dynamic spectrum of this line shows a pattern indicating the presence of non-radial pulsation, consistent with the previously reported period of 3.5 h. The edge variability around -2300 km s-1 in the saturated wind lines of C Iv and N V is nearly identical to the edge variability in the unsaturated Si Iv line, supporting the view that this type of variability is also due to the moving DACs. A detailed analysis using Fourier reconstructions reveals that each DAC actually consists of 2 different components: a ``fast'' and a ``slow'' one which merge at higher velocities. Based on observations obtained using the International Ultraviolet Explorer, collected at NASA Goddard Space Flight Center and Villafranca Satellite Tracking Station of the European Space Agency.

To score or not to score: a qualitative study on GPs views on the use of instruments for depression.

PubMed

Pettersson, Agneta; Björkelund, Cecilia; Petersson, Eva-Lisa

2014-04-01

To improve the detection, diagnosis and follow-up of depression in primary care patients, it has been proposed that GPs should employ assessment instruments as a complement to the consultation. However, most GPs do not use such instruments routinely. To explore perceptions of Swedish GPs on the use of instruments in the medical consultation. Twenty-seven GPs discussed in five focus groups that were digitally recorded, transcribed verbatim and analysed by systematic text condensation. Six code groups emerged from the focus group discussions: (i) a perceived pressure from authorities and psychiatry to report depression scores; (ii) the scores were considered to be of limited value for the GP but could help the patient by facilitating sick leave compensation and hospitalization; (iii) instruments hampered the dialogue with the patient and non-verbal information was lost; (iv) the reliability of questionnaires was questioned; (v) instruments were seen as not fitting into primary care and GPs were uncertain how to use them and (vi) the main advantage of instruments was to promote communication with specific categories of patients. Using instruments to obtain a quantitative score of depression was of no benefit to the GPs. Given the weak evidence for the clinical relevance of many instruments, there is little reason to introduce them into practice. However, the instruments can facilitate communication with external actors and specific groups of patients.

Dynamic modal estimation using instrumental variables

NASA Technical Reports Server (NTRS)

Salzwedel, H.

1980-01-01

A method to determine the modes of dynamical systems is described. The inputs and outputs of a system are Fourier transformed and averaged to reduce the error level. An instrumental variable method that estimates modal parameters from multiple correlations between responses of single input, multiple output systems is applied to estimate aircraft, spacecraft, and off-shore platform modal parameters.

Teachers' Pedagogical Management and Instrumental Performance in Students of an Artistic Higher Education School

ERIC Educational Resources Information Center

De La Cruz Bautista, Edwin

2017-01-01

This research aims to know the relationship between the variables teachers' pedagogical management and instrumental performance in students from an Artistic Higher Education School. It is a descriptive and correlational research that seeks to find the relationship between both variables. The sample of the study consisted of 30 students of the…

Polychronometry: The Study of Time Variables in Behavior.

ERIC Educational Resources Information Center

Mackey, William Francis

There is a growing need for instrumentation which can enable us to observe and compute phenomena that take place in time. Although problems of observation, computation, interpretation and categorization vary from field to field and from problem to problem, it is possible to design an instrument for use in any situation where time-variables have to…

Predicting Preservice Music Teachers' Performance Success in Instrumental Courses Using Self-Regulated Study Strategies and Predictor Variables

ERIC Educational Resources Information Center

Ersozlu, Zehra N.; Nietfeld, John L.; Huseynova, Lale

2017-01-01

The purpose of this study was to examine the extent to which self-regulated study strategies and predictor variables predict performance success in instrumental performance college courses. Preservice music teachers (N = 123) from a music education department in two state universities in Turkey completed the Music Self-Regulated Studying…

Can Two Psychotherapy Process Measures Be Dependably Rated Simultaneously? A Generalizability Study

ERIC Educational Resources Information Center

Ulvenes, Pal G.; Berggraf, Lene; Hoffart, Asle; Levy, Raymon A.; Ablon, J. Stuart; McCullough, Leigh; Wampold, Bruce E.

2012-01-01

Observer ratings in psychotherapy are a common way of collecting information in psychotherapy research. However, human observers are imperfect instruments, and their ratings may be subject to variability from several sources. One source of variability can be raters' assessing more than 1 instrument at a time. The purpose of this research is to…

Search for correlated UV and x ray absorption of NGC 3516

NASA Technical Reports Server (NTRS)

Martin, Christopher; Halpern, Jules P.; Kolman, Michiel

1991-01-01

NGC 3516, a low-luminosity Seyfert galaxy, is one of a small fraction of Seyfert galaxies that exhibit broad absorption in a resonance line. In order to determine whether the UV and x ray absorption in NGC 3516 are related, 5 IUE observations were obtained, quasi-simultaneously with 4 Ginga observations. The results are presented and discussed. The following subject areas are covered: short-term UV variability; emission lines; galactic absorption lines; the C IV, N V, and Si IV absorption features; lower limit on the carbon column density; estimate of the distance from the absorber to the continuum source; variability in the continuum and absorption; a comparison with BAL QSO's; and the x ray-UV connection.

Psychological variables and Wechsler Adult Intelligence Scale-IV performance.

PubMed

Gass, Carlton S; Gutierrez, Laura

2017-01-01

The MMPI-2 and WAIS-IV are commonly used together in neuropsychological evaluations yet little is known about their interrelationships. This study explored the potential influence of psychological factors on WAIS-IV performance in a sample of 180 predominantly male veteran referrals that underwent a comprehensive neuropsychological examination in a VA Medical Center. Exclusionary criteria included failed performance validity testing and self-report distortion on the MMPI-2. A Principal Components Analysis was performed on the 15 MMPI-2 content scales, yielding three broader higher-order psychological dimensions: Internalized Emotional Dysfunction (IED), Externalized Emotional Dysfunction (EED), and Fear. Level of IED was not related to performance on the WAIS-IV Full Scale IQ or its four indexes: (Verbal Comprehension, Perceptual Reasoning, Working Memory, and Processing Speed). EED was not related to WAIS-IV performance. Level of Fear, which encompasses health preoccupations (HEA) and distorted perceptions (BIZ), was significantly related to WAIS-IV Full Scale IQ and Verbal Comprehension. These results challenge the common use of high scores on the MMPI-2 IED measures (chiefly depression and anxiety) to explain deficient WAIS-IV performance. In addition, they provide impetus for further investigation of the relation between verbal intelligence and Fear.

Hydroclimatic variability and predictability: a survey of recent research

DOE PAGES

Koster, Randal D.; Betts, Alan K.; Dirmeyer, Paul A.; ...

2017-07-25

Recent research in large-scale hydroclimatic variability is surveyed, focusing on five topics: (i) variability in general, (ii) droughts, (iii) floods, (iv) land–atmosphere coupling, and (v) hydroclimatic prediction. Moreover, each surveyed topic is supplemented by illustrative examples of recent research, as presented at a 2016 symposium honoring the career of Professor Eric Wood. Altogether, the recent literature and the illustrative examples clearly show that current research into hydroclimatic variability is strong, vibrant, and multifaceted.

Hydroclimatic variability and predictability: a survey of recent research

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

Koster, Randal D.; Betts, Alan K.; Dirmeyer, Paul A.

Recent research in large-scale hydroclimatic variability is surveyed, focusing on five topics: (i) variability in general, (ii) droughts, (iii) floods, (iv) land–atmosphere coupling, and (v) hydroclimatic prediction. Moreover, each surveyed topic is supplemented by illustrative examples of recent research, as presented at a 2016 symposium honoring the career of Professor Eric Wood. Altogether, the recent literature and the illustrative examples clearly show that current research into hydroclimatic variability is strong, vibrant, and multifaceted.

Articular congruity is associated with short-term clinical outcomes of operatively treated SER IV ankle fractures.

PubMed

Berkes, Marschall B; Little, Milton T M; Lazaro, Lionel E; Pardee, Nadine C; Schottel, Patrick C; Helfet, David L; Lorich, Dean G

2013-10-02

With regard to supination-external rotation type-IV (SER IV) ankle fractures, there is no consensus regarding which patient, injury, and treatment variables most strongly influence clinical outcome. The purpose of this investigation was to examine the impact of articular surface congruity on the functional outcomes of operatively treatment of SER IV ankle fractures. A prospectively generated database consisting of operatively treated SER IV ankle fractures was reviewed. Postoperative computed tomography (CT) scans were used to assess ankle joint congruity. Ankles were considered incongruent in the presence of >2 mm of articular step-off, intra-articular loose bodies, or an articular surface gap of >2 mm (despite an otherwise anatomic reduction) due to joint impaction and comminution. Patients with at least one year of clinical follow-up were eligible for analysis. The primary and secondary outcome measures were the Foot and Ankle Outcome Score (FAOS) and ankle motion. One hundred and eight SER IV fractures met our inclusion criteria. The average duration of follow-up was twenty-one months. Seventy-two patients (67%) had a congruent ankle joint, and thirty-six (33%) had elements of articular surface incongruity on postoperative CT scanning. These two groups were similar with regard to comorbidities and injury and treatment variables. At the time of the final follow-up, the group with articular incongruity had a significantly worse FAOS with regard to symptoms (p = 0.012), pain (p = 0.004), and activities of daily living (p = 0.038). Those with articular incongruity had worse average scores in the FAOS sport domain as well. No significant differences in ankle motion were found between the two groups. In this population of patients with an operatively treated SER IV ankle fracture, the presence of postoperative articular incongruity correlated with inferior early clinical outcomes. Orthopaedic surgeons should scrutinize ankle fracture reductions and strive for perfection to allow for the best possible clinical outcome. Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

[Conceptual foundation of the operational diagnostic approach in psychiatry].

PubMed

Jäger, M; Strauss, A; Frasch, K; Becker, T

2007-08-01

Based on the pioneering work of Emil Kraepelin, Karl Jaspers, Kurt Schneider and representatives of logical empiricism, the basic principles of the operational diagnostic approach in psychiatry are described. Operational diagnostic systems like ICD-10 and DSM-IV aimed at a standardisation of psychiatric language which can be accepted by different schools in psychiatry. However, ICD-10 and DSM-IV should not be misinterpreted as "nosology" because they do not reflect a specific model of psychiatric diseases. The advantages of operational diagnostic systems as instruments for communication in a clinical and scientific context are limited by the fact that they disregard the subjective psychopathology. This dimension, however, deserves attention in clinic and research.

Revisiting NMR composite pulses for broadband 2H excitation

PubMed Central

Shen, Ming; Roopchand, Rabia; Mananga, Eugene S.; Amoureux, Jean-Paul; Chen, Qun; Boutis, Gregory S.; Hu, Bingwen

2014-01-01

Quadrupolar echo NMR spectroscopy of static solids often requires RF excitation that covers spectral widths exceeding 100 kHz, which is difficult to obtain due to instrumental limitations. In this work we revisit four well-known composite pulses (COM-I, II, III and IV) for broadband excitation in deuterium quadrupolar echo spectroscopy. These composite pulses are combined with several phase cycling schemes that were previously shown to decrease finite pulse width distortions in deuterium solid-echo experiments performed with two single pulses. The simulations and experiments show that COM-II and IV composite pulses combined with an 8-step phase cycling aid in achieving broadband excitation with limited pulse width distortions. PMID:25583576

Narrow absorption lines with two observations from the Sloan Digital Sky Survey

NASA Astrophysics Data System (ADS)

Chen, Zhi-Fu; Gu, Qiu-Sheng; Chen, Yan-Mei; Cao, Yue

2015-07-01

We assemble 3524 quasars from the Sloan Digital Sky Survey (SDSS) with repeated observations to search for variations of the narrow C IV λ λ 1548,1551 and Mg II λ λ 2796,2803 absorption doublets in spectral regions shortward of 7000 Å in the observed frame, which corresponds to time-scales of about 150-2643 d in the quasar rest frame. In these quasar spectra, we detect 3580 C IV absorption systems with zabs = 1.5188-3.5212 and 1809 Mg II absorption systems with zabs = 0.3948-1.7167. In term of the absorber velocity (β) distribution in the quasar rest frame, we find a substantial number of C IV absorbers with β < 0.06, which might be connected to absorption of quasar outflows. The outflow absorption peaks at υ ≈ 2000 km s^{-1} and drops rapidly below this peak value. Among 3580 C IV absorption systems, 52 systems (˜1.5 per cent) show obvious variations in equivalent widths in the absorber rest frame (Wr): 16 enhanced, 16 emerged, 12 weakened and 8 disappeared systems, respectively. We find that changes in Wrλ1548 are related neither to the time-scales of the two SDSS observations nor to absorber velocities in the quasar rest frame. Variable absorption in low-ionization species is important to constrain the physical conditions of the absorbing gas. There are two variable Mg II absorption systems measured from SDSS spectra detected by Hacker et al. However, in our Mg II absorption sample, we find that neither shows variable absorption with confident levels of >4σ for λ2796 lines and >3σ for λ2803 lines.

34 CFR 682.511 - Procedures for filing a claim.

Code of Federal Regulations, 2013 CFR

2013-07-01

...) The repayment instrument. (iv) A payment history, as described in § 682.414(a)(3)(ii)(I). (v) A collection history, as described in § 682.414(a)(3)(ii)(J). (vi) A copy of the final demand letter if... America of all rights, title, and interest of the lender in the note underlying the claim. (d) Bankruptcy...

34 CFR 682.511 - Procedures for filing a claim.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) The repayment instrument. (iv) A payment history, as described in § 682.414(a)(3)(ii)(I). (v) A collection history, as described in § 682.414(a)(3)(ii)(J). (vi) A copy of the final demand letter if... America of all rights, title, and interest of the lender in the note underlying the claim. (d) Bankruptcy...

34 CFR 682.511 - Procedures for filing a claim.

Code of Federal Regulations, 2012 CFR

2012-07-01

...) The repayment instrument. (iv) A payment history, as described in § 682.414(a)(3)(ii)(I). (v) A collection history, as described in § 682.414(a)(3)(ii)(J). (vi) A copy of the final demand letter if... America of all rights, title, and interest of the lender in the note underlying the claim. (d) Bankruptcy...

Mission Specialist (MS) Allen experiments with beverage on middeck

NASA Image and Video Library

1982-11-16

STS005-04-134 (11-16 Nov. 1982) --- Astronaut Joseph P. Allen IV, STS-5 mission specialist, uses beverage container and drinking straw, experiments with microgravity characteristics of orange juice on middeck in front of the Development Flight Instrument (DFI) unit and forward lockers. Allen laughs as he watches the results of his experimentation. Photo credit: NASA

Referred Students' Performance on the Reynolds Intellectual Assessment Scales and the Wechsler Intelligence Scale for Children--Fourth Edition

ERIC Educational Resources Information Center

Edwards, Oliver W.; Paulin, Rachel V.

2007-01-01

This study investigates the convergent relations of the Reynolds Intellectual Assessment Scales (RIAS) and the Wechsler Intelligence Scale for Children--Fourth Edition (WISC-IV). Data from counterbalanced administrations of each instrument to 48 elementary school students referred for psychoeducational testing were examined. Analysis of the 96…

Under What Assumptions Do Site-by-Treatment Instruments Identify Average Causal Effects?

ERIC Educational Resources Information Center

Reardon, Sean F.; Raudenbush, Stephen W.

2011-01-01

The purpose of this paper is to clarify the assumptions that must be met if this--multiple site, multiple mediator--strategy, hereafter referred to as "MSMM," is to identify the average causal effects (ATE) in the populations of interest. The authors' investigation of the assumptions of the multiple-mediator, multiple-site IV model demonstrates…

Absolute Risk Aversion and the Returns to Education.

ERIC Educational Resources Information Center

Brunello, Giorgio

2002-01-01

Uses 1995 Italian household income and wealth survey to measure individual absolute risk aversion of 1,583 married Italian male household heads. Uses this measure as an instrument for attained education in a standard-log earnings equation. Finds that the IV estimate of the marginal return to schooling is much higher than the ordinary least squares…

The Reliability and Validity of the Dominic Interactive: A Computerized Child Report Instrument for Mental Health Problems

ERIC Educational Resources Information Center

Kuijpers, Rowella C. W. M.; Otten, Roy; Krol, Nicole P. C. M.; Vermulst, Ad A.; Engels, Rutger C. M. E.

2013-01-01

Background: Children and youths' self-report of mental health problems is considered essential but complicated. Objective: This study examines the psychometric properties of the Dominic Interactive, a computerized DSM-IV based self-report questionnaire and explores informant correspondence. Methods: The Dominic Interactive was administered to 214…

An Assessment of the Need for Standard Variable Names for Airborne Field Campaigns

NASA Astrophysics Data System (ADS)

Beach, A. L., III; Chen, G.; Northup, E. A.; Kusterer, J.; Quam, B. M.

2017-12-01

The NASA Earth Venture Program has led to a dramatic increase in airborne observations, requiring updated data management practices with clearly defined data standards and protocols for metadata. An airborne field campaign can involve multiple aircraft and a variety of instruments. It is quite common to have different instruments/techniques measure the same parameter on one or more aircraft platforms. This creates a need to allow instrument Principal Investigators (PIs) to name their variables in a way that would distinguish them across various data sets. A lack of standardization of variables names presents a challenge for data search tools in enabling discovery of similar data across airborne studies, aircraft platforms, and instruments. This was also identified by data users as one of the top issues in data use. One effective approach for mitigating this problem is to enforce variable name standardization, which can effectively map the unique PI variable names to fixed standard names. In order to ensure consistency amongst the standard names, it will be necessary to choose them from a controlled list. However, no such list currently exists despite a number of previous efforts to establish a sufficient list of atmospheric variable names. The Atmospheric Composition Variable Standard Name Working Group was established under the auspices of NASA's Earth Science Data Systems Working Group (ESDSWG) to solicit research community feedback to create a list of standard names that are acceptable to data providers and data users This presentation will discuss the challenges and recommendations of standard variable names in an effort to demonstrate how airborne metadata curation/management can be improved to streamline data ingest, improve interoperability, and discoverability to a broader user community.

Use of allele scores as instrumental variables for Mendelian randomization

PubMed Central

Burgess, Stephen; Thompson, Simon G

2013-01-01

Background An allele score is a single variable summarizing multiple genetic variants associated with a risk factor. It is calculated as the total number of risk factor-increasing alleles for an individual (unweighted score), or the sum of weights for each allele corresponding to estimated genetic effect sizes (weighted score). An allele score can be used in a Mendelian randomization analysis to estimate the causal effect of the risk factor on an outcome. Methods Data were simulated to investigate the use of allele scores in Mendelian randomization where conventional instrumental variable techniques using multiple genetic variants demonstrate ‘weak instrument’ bias. The robustness of estimates using the allele score to misspecification (for example non-linearity, effect modification) and to violations of the instrumental variable assumptions was assessed. Results Causal estimates using a correctly specified allele score were unbiased with appropriate coverage levels. The estimates were generally robust to misspecification of the allele score, but not to instrumental variable violations, even if the majority of variants in the allele score were valid instruments. Using a weighted rather than an unweighted allele score increased power, but the increase was small when genetic variants had similar effect sizes. Naive use of the data under analysis to choose which variants to include in an allele score, or for deriving weights, resulted in substantial biases. Conclusions Allele scores enable valid causal estimates with large numbers of genetic variants. The stringency of criteria for genetic variants in Mendelian randomization should be maintained for all variants in an allele score. PMID:24062299

Temporal Lobe Reactions After Carbon Ion Radiation Therapy: Comparison of Relative Biological Effectiveness–Weighted Tolerance Doses Predicted by Local Effect Models I and IV

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

Gillmann, Clarissa, E-mail: clarissa.gillmann@med.uni-heidelberg.de; Jäkel, Oliver; Heidelberg Ion Beam Therapy Center

2014-04-01

Purpose: To compare the relative biological effectiveness (RBE)–weighted tolerance doses for temporal lobe reactions after carbon ion radiation therapy using 2 different versions of the local effect model (LEM I vs LEM IV) for the same patient collective under identical conditions. Methods and Materials: In a previous study, 59 patients were investigated, of whom 10 experienced temporal lobe reactions (TLR) after carbon ion radiation therapy for low-grade skull-base chordoma and chondrosarcoma at Helmholtzzentrum für Schwerionenforschung (GSI) in Darmstadt, Germany in 2002 and 2003. TLR were detected as visible contrast enhancements on T1-weighted MRI images within a median follow-up time ofmore » 2.5 years. Although the derived RBE-weighted temporal lobe doses were based on the clinically applied LEM I, we have now recalculated the RBE-weighted dose distributions using LEM IV and derived dose-response curves with Dmax,V-1 cm³ (the RBE-weighted maximum dose in the remaining temporal lobe volume, excluding the volume of 1 cm³ with the highest dose) as an independent dosimetric variable. The resulting RBE-weighted tolerance doses were compared with those of the previous study to assess the clinical impact of LEM IV relative to LEM I. Results: The dose-response curve of LEM IV is shifted toward higher values compared to that of LEM I. The RBE-weighted tolerance dose for a 5% complication probability (TD{sub 5}) increases from 68.8 ± 3.3 to 78.3 ± 4.3 Gy (RBE) for LEM IV as compared to LEM I. Conclusions: LEM IV predicts a clinically significant increase of the RBE-weighted tolerance doses for the temporal lobe as compared to the currently applied LEM I. The limited available photon data do not allow a final conclusion as to whether RBE predictions of LEM I or LEM IV better fit better clinical experience in photon therapy. The decision about a future clinical application of LEM IV therefore requires additional analysis of temporal lobe reactions in a comparable photon-treated collective using the same dosimetric variable as in the present study.« less

The C IV doublet ratio intensity effect in symbiotic stars

NASA Technical Reports Server (NTRS)

Michalitsianos, A. G.; Fahey, M.; Kafatos, M.; Viotti, R.; Cassatella, A.

1988-01-01

High-resolution UV spectra in the 1200-2000 wavelength range of the symbiotic variable R Aqr and its nebular jet were obtained in July 1987 with the IUE. The line profile structure of the C IV 1548, 1550 doublet in the jet indicates multicomponent velocity structure from an optically thin emitting gas. The C IV doublet profiles in the compact H II region engulfing the Mira and hot companion binary also suggest multicomponent structure with radial velocities up to about -100 km/s. The value of the doublet intensity ratio in the R Aqr H II region has been observed in other similar symbiotic stars, such as RX Pup. It is suggested that the anomalous behavior of the C IV doublet intensities may be useful for studying the spatial structure and temporal nature of winds in symbiotic stars.

EVIDENCE FOR PHOTOIONIZATION-DRIVEN BROAD ABSORPTION LINE VARIABILITY

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

Wang, Tinggui; Yang, Chenwei; Wang, Huiyuan

2015-12-01

We present a qualitative analysis of the variability of quasar broad absorption lines using the large multi-epoch spectroscopic data set of the Sloan Digital Sky Survey Data Release 10. We confirm that variations of absorption lines are highly coordinated among different components of the same ion or the same absorption component of different ions for C iv, Si iv, and N v. Furthermore, we show that the equivalent widths (EWs) of the lines decrease or increase statistically when the continuum brightens or dims. This is further supported by the synchronized variations of emission and absorption-line EWs when the well-established intrinsicmore » Baldwin effect for emission lines is taken into account. We find that the emergence of an absorption component is usually accompanied by the dimming of the continuum while the disappearance of an absorption-line component is accompanied by the brightening of the continuum. This suggests that the emergence or disappearance of a C iv absorption component is only the extreme case, when the ionic column density is very sensitive to continuum variations or the continuum variability the amplitude is larger. These results support the idea that absorption-line variability is driven mainly by changes in the gas ionization in response to continuum variations, that the line-absorbing gas is highly ionized, and in some extreme cases, too highly ionized to be detected in UV absorption lines. Due to uncertainties in the spectroscopic flux calibration, we cannot quantify the fraction of quasars with asynchronized continuum and absorption-line variations.« less

Do Two or More Multicomponent Instruments Measure the Same Construct? Testing Construct Congruence Using Latent Variable Modeling

ERIC Educational Resources Information Center

Raykov, Tenko; Marcoulides, George A.; Tong, Bing

2016-01-01

A latent variable modeling procedure is discussed that can be used to test if two or more homogeneous multicomponent instruments with distinct components are measuring the same underlying construct. The method is widely applicable in scale construction and development research and can also be of special interest in construct validation studies.…

Comparison and covalidation of ozone anomalies and variability observed in SBUV(/2) and Umkehr northern midlatitude ozone profile estimates

NASA Astrophysics Data System (ADS)

Petropavlovskikh, I.; Ahn, Changwoo; Bhartia, P. K.; Flynn, L. E.

2005-03-01

This analysis presents comparisons of upper-stratosphere ozone information observed by two independent systems: the Solar Backscatter UltraViolet (SBUV and SBUV/2) satellite instruments, and ground-based Dobson spectrophotometers. Both the new SBUV Version 8 and the new UMK04 profile retrieval algorithms are optimized for studying long-term variability and trends in ozone. Trend analyses of the ozone time series from the SBUV(/2) data set are complex because of the multiple instruments involved, changes in the instruments' geo-location, and short periods of overlaps for inter-calibrations among different instruments. Three northern middle latitudes Dobson ground stations (Arosa, Boulder, and Tateno) are used in this analysis to validate the trend quality of the combined 25-year SBUV/2 time series, 1979 to 2003. Generally, differences between the satellite and ground-based data do not suggest any significant time-dependent shifts or trends. The shared features confirm the value of these data sets for studies of ozone variability.

C IV absorption-line variability in X-ray-bright broad absorption-line quasi-stellar objects

NASA Astrophysics Data System (ADS)

Joshi, Ravi; Chand, Hum; Srianand, Raghunathan; Majumdar, Jhilik

2014-07-01

We report the kinematic shift and strength variability of the C IV broad absorption-line (BAL) trough in two high-ionization X-ray-bright quasi-stellar objects (QSOs): SDSS J085551+375752 (at zem ˜ 1.936) and SDSS J091127+055054 (at zem ˜ 2.793). Both these QSOs have shown a combination of profile shifts and the appearance and disappearance of absorption components belonging to a single BAL trough. The observed average kinematic shift of the whole BAL profile resulted in an average deceleration of ˜-0.7 ± 0.1, -2.0 ± 0.1 cm s-2 over rest-frame time-spans of 3.11 and 2.34 yr for SDSS J085551+375752 and SDSS J091127+055054, respectively. To our knowledge, these are the largest kinematic shifts known, exceeding by factors of about 2.8 and 7.8 the highest deceleration reported in the literature; this makes both objects potential candidates to investigate outflows using multiwavelength monitoring of their line and continuum variability. We explore various possible mechanisms to understand the observed profile variations. Outflow models involving many small self-shielded clouds, probably moving in a curved path, provide the simplest explanation for the C IV BAL strength and velocity variations, along with the X-ray-bright nature of these sources.

Evaluation of peak force of a manually operated chiropractic adjusting instrument with an adapter for use in animals.

PubMed

Duarte, Felipe Coutinho Kullmann; Kolberg, Carolina; Barros, Rodrigo R; Silva, Vivian G A; Gehlen, Günter; Vassoler, Jakson M; Partata, Wania A

2014-05-01

This study was designed to assess the peak force of a manually operated chiropractic adjusting instrument, the Activator Adjusting Instrument 4 (AAI 4), with an adapter for use in animals, which has a 3- to 4-fold smaller contact surface area than the original rubber tip. Peak force was determined by thrusting the AAI 4 with the adapter or the original rubber tip onto a load cell. First, the AAI 4 was applied perpendicularly by a doctor of chiropractic onto the load cell. Then, the AAI 4 was fixed in a rigid framework and applied to the load cell. This procedure was done to prevent any load on the load cell before the thrust impulse. In 2 situations, trials were performed with the AAI 4 at all force settings (settings I, II, III, and IV, minimum to maximum, respectively). A total of 50000 samples per second over a period of 3 seconds were collected. In 2 experimental protocols, the use of the adapter in the AAI 4 increased the peak force only with setting I. The new value was around 80% of the maximum value found for the AAI 4. Nevertheless, the peak force values of the AAI 4 with the adapter and with the original rubber tip in setting IV were similar. The adapter effectively determines the maximum peak force value at force setting I of AAI 4. Copyright © 2014 National University of Health Sciences. Published by Mosby, Inc. All rights reserved.

Tiros IV Radiation Data Catalog and Users' Manual

NASA Technical Reports Server (NTRS)

Kunde, V. G.

1963-01-01

The TIROS IV Meteorological Satellite contains a medium resolution scanning radiometer. Two of the channels of this instrument are sensitive to reflected solar radiation and the remaining two respond to emitted thermal radiation from the earth and its atmosphere. The two thermal channels are calibrated in terms of equivalent blackbody temperatures, and the reflected solar radiation channels in terms of effective radiant emittances. The calibration data, along with orbital and attitude data and the radiation data from the satellite, were incorporated in a computer program for an IBM 7090 which was used to produce, in binary form, the "Final Meteorological Radiation Tape" which is the basic repository of all radiation data. After launch, the radiometer displaye d the same degradation of response characteristics as did its predecessors in TIROS II and TIROS III. The onset of degradation results in a departure of the data from the prelaunch laboratory calibration. The cause of degradation has not been determined, and the matter is still being studied at the Goddard Space Flight Center. Before work with the TIROS IV radiation data is attempted, an understanding of the radiometer, its calibration, and the problems encountered in the experiment, especially from response degradation, is essential. The instrumentation design, development work, and the calibrations herein described were performed by the Goddard Space Flight Center Staff, whereas the computer and programming efforts were carried out jointly by the staffs of the National Weather Satellite Center, U. S. Weather Bureau, and the Goddard Space Flight Center. In this Catalog-Manual, the radiometer an d its calibration, data processing, the "Final Meteorological Radiation Tape", the observed degradation patterns, and possible corrections for degradation are discussed. The Catalog-Manual also includes, in two forms, documentation of each orbit of successfully reduced radiation data acquired by TIROS IV. One method of presentation is the Index of Final Meteorological Radiation Tapes and the other is a Subpoint Track, Summary of Available Radiation Data in diagrammatic form.

Dynamic tunable notch filters for the Antarctic Impulsive Transient Antenna (ANITA)

NASA Astrophysics Data System (ADS)

Allison, P.; Banerjee, O.; Beatty, J. J.; Connolly, A.; Deaconu, C.; Gordon, J.; Gorham, P. W.; Kovacevich, M.; Miki, C.; Oberla, E.; Roberts, J.; Rotter, B.; Stafford, S.; Tatem, K.; Batten, L.; Belov, K.; Besson, D. Z.; Binns, W. R.; Bugaev, V.; Cao, P.; Chen, C.; Chen, P.; Chen, Y.; Clem, J. M.; Cremonesi, L.; Dailey, B.; Dowkontt, P. F.; Hsu, S.; Huang, J.; Hupe, R.; Israel, M. H.; Kowalski, J.; Lam, J.; Learned, J. G.; Liewer, K. M.; Liu, T. C.; Ludwig, A. B.; Matsuno, S.; Mulrey, K.; Nam, J.; Nichol, R. J.; Novikov, A.; Prohira, S.; Rauch, B. F.; Ripa, J.; Romero-Wolf, A.; Russell, J.; Saltzberg, D.; Seckel, D.; Shiao, J.; Stockham, J.; Stockham, M.; Strutt, B.; Varner, G. S.; Vieregg, A. G.; Wang, S.; Wissel, S. A.; Wu, F.; Young, R.

2018-06-01

The Antarctic Impulsive Transient Antenna (ANITA) is a NASA long-duration balloon experiment with the primary goal of detecting ultra-high-energy (> 1018eV) neutrinos via the Askaryan Effect. The fourth ANITA mission, ANITA-IV, recently flew from Dec 2 to Dec 29, 2016. For the first time, the Tunable Universal Filter Frontend (TUFF) boards were deployed for mitigation of narrow-band, anthropogenic noise with tunable, switchable notch filters. The TUFF boards also performed second-stage amplification by approximately 45 dB to boost the ∼ μV-level radio frequency (RF) signals to ∼ mV-level for digitization, and supplied power via bias tees to the first-stage, antenna-mounted amplifiers. The other major change in signal processing in ANITA-IV is the resurrection of the 90 ° hybrids deployed previously in ANITA-I, in the trigger system, although in this paper we focus on the TUFF boards. During the ANITA-IV mission, the TUFF boards were successfully operated throughout the flight. They contributed to a factor of 2.8 higher total instrument livetime on average in ANITA-IV compared to ANITA-III due to reduction of narrow-band, anthropogenic noise before a trigger decision is made.

Memory assessment and depression: testing for factor structure and measurement invariance of the Wechsler Memory Scale-Fourth Edition across a clinical and matched control sample.

PubMed

Pauls, Franz; Petermann, Franz; Lepach, Anja Christina

2013-01-01

Between-group comparisons are permissible and meaningfully interpretable only if diagnostic instruments are proved to measure the same latent dimensions across different groups. Addressing this issue, the present study was carried out to provide a rigorous test of measurement invariance. Confirmatory factor analyses were used to determine which model solution could best explain memory performance as measured by the Wechsler Memory Scale-Fourth Edition (WMS-IV) in a clinical depression sample and in healthy controls. Multigroup confirmatory factor analysis was conducted to evaluate the evidence for measurement invariance. A three-factor model solution including the dimensions of auditory memory, visual memory, and visual working memory was identified to best fit the data in both samples, and measurement invariance was partially satisfied. The results supported clinical utility of the WMS-IV--that is, auditory and visual memory performances of patients with depressive disorders are interpretable on the basis of the WMS-IV standardization data. However, possible differences in visual working memory functions between healthy and depressed individuals could restrict comparisons of the WMS-IV working memory index.

Risk Factors for Sexual Violence in the Military: An Analysis of Sexual Assault and Sexual Harassment Incidents and Reporting

DTIC Science & Technology

2017-03-01

53 ix LIST OF TABLES Table 1. Descriptive Statistics for Control Variables by... Statistics for Control Variables by Gender (Random Subsample with Complete Survey) ............................................................30 Table...empirical analysis. Chapter IV describes the summary statistics and results. Finally, Chapter V offers concluding thoughts, study limitations, and

Robust best linear estimator for Cox regression with instrumental variables in whole cohort and surrogates with additive measurement error in calibration sample.

PubMed

Wang, Ching-Yun; Song, Xiao

2016-11-01

Biomedical researchers are often interested in estimating the effect of an environmental exposure in relation to a chronic disease endpoint. However, the exposure variable of interest may be measured with errors. In a subset of the whole cohort, a surrogate variable is available for the true unobserved exposure variable. The surrogate variable satisfies an additive measurement error model, but it may not have repeated measurements. The subset in which the surrogate variables are available is called a calibration sample. In addition to the surrogate variables that are available among the subjects in the calibration sample, we consider the situation when there is an instrumental variable available for all study subjects. An instrumental variable is correlated with the unobserved true exposure variable, and hence can be useful in the estimation of the regression coefficients. In this paper, we propose a nonparametric method for Cox regression using the observed data from the whole cohort. The nonparametric estimator is the best linear combination of a nonparametric correction estimator from the calibration sample and the difference of the naive estimators from the calibration sample and the whole cohort. The asymptotic distribution is derived, and the finite sample performance of the proposed estimator is examined via intensive simulation studies. The methods are applied to the Nutritional Biomarkers Study of the Women's Health Initiative. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Investigation of Music Student Efficacy as Influenced by Age, Experience, Gender, Ethnicity, and Type of Instrument Played in South Carolina

ERIC Educational Resources Information Center

White, Norman

2010-01-01

The purpose of this research study was to quantitatively examine South Carolina high school instrumental music students' self-efficacy as measured by the Generalized Self-Efficacy (GSE) instrument (Schwarzer & Jerusalem, 1993). The independent variables of age, experience, gender, ethnicity, and type of instrument played) were correlated with…

Synthetic Spectral Ananlysis of the Nova-Like Variable KQ Mon

NASA Astrophysics Data System (ADS)

Wolfe, Aaron; Sion, E.

2011-01-01

KQ Mon is classified as a nova-like variable with an uncertain orbital period of 0.128 d. Optical spectra (Zwitter, T. & Munari, U.1994, A&AS, 107, 503) reveal no emission lines but strong Balmer absorption features. High speed flickering has been observed indicative of accretion. IUE spectra reveal deep absorption lines due to C III, C II, Si III, Si IV, C IV, He II but no P Cygni profiles indicative of outflow. Its classification in Ritter and Kolb (2006) as a UX UMa type nova-like is uncertain. We have carried out the first synthetic spectral analysis of the IUE archival spectra of KQ Mon with realistic accretion disk models with vertical structure and high gravity photosphere models. The results of our model atmosphere and model accretion disk analyses are presented. We discuss the properties that we have derived for KQ Mon and compare KQ Mon with other nova-like variables viewed at low inclination. This work was supported in part by NSF grant AST0807892 to Villanova University.

Health status, mental health and air quality: evidence from pensioners in Europe.

PubMed

Giovanis, Eleftherios; Ozdamar, Oznur

2018-05-01

Environmental quality is an important determinant of individuals' well-being and one of the main concerns of the governments is the improvement on air quality and the protection of public health. This is especially the case of sensitive demographic groups, such as the old aged people. However, the question this study attempts to answer is how do individuals value the effects on the environment. The study explores the effects of old and early public pension schemes, as well as the impact of air pollution on health status of retired citizens. The empirical analysis relies on detailed micro-level data derived from the Survey of Health, Ageing and Retirement in Europe (SHARE). As proxies for health, we use the general health status and the Eurod mental health indicator. We examine two air pollutants: the sulphur dioxide (SO 2 ) and ground-level ozone (O 3 ). Next, we calculate the marginal willingness-to-pay (MWTP) which shows how much the people are willing to pay for improvement in air quality. We apply various quantitative techniques and approaches, including the fixed effects ordinary least squares (OLS) and the fixed effects instrumental variables (IV) approach. The last approach is applied to reduce the endogeneity problem coming from possible reverse causality between the air pollution, pensions and the health outcomes. For robustness check, we apply also a structural equation modelling (SEM) which is proper when the outcomes are latent variables. Based on our favoured IV estimates and the health status, we find that the MWTP values for one unit decrease in SO 2 and O 3 are respectively €221 and €88 per year. The respective MWTP values using the Eurod measure are €155 and €68. Overall, improvement of health status implies reduction in health expenditures, and in previous literature, ageing has been traditionally considered the most important determinant. However, this study shows that health lifestyle and socio-economic status, such as education and marital status, are more important, and furthermore, air pollution cannot be ignored in the agenda of policy makers.

Mapping Variables.

ERIC Educational Resources Information Center

Stone, Mark H.; Wright, Benjamin D.; Stenner, A. Jackson

1999-01-01

Describes mapping variables, the principal technique for planning and constructing a test or rating instrument. A variable map is also useful for interpreting results. Provides several maps to show the importance and value of mapping a variable by person and item data. (Author/SLD)

The sn stars - Magnetically controlled stellar winds among the helium-weak stars

NASA Technical Reports Server (NTRS)

Shore, Steven N.; Brown, Douglas N.; Sonneborn, George

1987-01-01

The paper reports observations of magnetically controlled stellar mass outflows in three helium-weak sn stars: HD 21699 = HR 1063; HD 5737 = Alpha Scl; and HD 79158 = 36 Lyn. IUE observations show that the C IV resonance doublet is variable on the rotational timescale but that there are no other strong-spectrum variations in the UV. Magnetic fields, which reverse sign on the rotational timescale, are present in all three stars. This phenomenology is interpreted in terms of jetlike mass loss above the magnetic poles, and these objects are discussed in the context of a general survey of the C IV and Si IV profiles of other more typical helium-weak stars.

Detection Limit of Smectite by Chemin IV Laboratory Instrument: Preliminary Implications for Chemin on the Mars Science Laboratory Mission

NASA Technical Reports Server (NTRS)

Archilles, Cherie; Ming, D. W.; Morris, R. V.; Blake, D. F.

2011-01-01

The CheMin instrument on the Mars Science Laboratory (MSL) is an miniature X-ray diffraction (XRD) and X-ray fluorescence (XRF) instrument capable of detecting the mineralogical and elemental compositions of rocks, outcrops and soils on the surface of Mars. CheMin uses a microfocus-source Co X-ray tube, a transmission sample cell, and an energy-discriminating X-ray sensitive CCD to produce simultaneous 2-D XRD patterns and energy-dispersive X-ray histograms from powdered samples. CRISM and OMEGA have identified the presence of phyllosilicates at several locations on Mars including the four candidate MSL landing sites. The objective of this study was to conduct preliminary studies to determine the CheMin detection limit of smectite in a smectite/olivine mixed mineral system.

Development and validation of a screening instrument for bipolar spectrum disorder: the Mood Disorder Questionnaire.

PubMed

Hirschfeld, R M; Williams, J B; Spitzer, R L; Calabrese, J R; Flynn, L; Keck, P E; Lewis, L; McElroy, S L; Post, R M; Rapport, D J; Russell, J M; Sachs, G S; Zajecka, J

2000-11-01

Bipolar spectrum disorders, which include bipolar I, bipolar II, and bipolar disorder not otherwise specified, frequently go unrecognized, undiagnosed, and untreated. This report describes the validation of a new brief self-report screening instrument for bipolar spectrum disorders called the Mood Disorder Questionnaire. A total of 198 patients attending five outpatient clinics that primarily treat patients with mood disorders completed the Mood Disorder Questionnaire. A research professional, blind to the Mood Disorder Questionnaire results, conducted a telephone research diagnostic interview by means of the bipolar module of the Structured Clinical Interview for DSM-IV. A Mood Disorder Questionnaire screening score of 7 or more items yielded good sensitivity (0.73) and very good specificity (0.90). The Mood Disorder Questionnaire is a useful screening instrument for bipolar spectrum disorder in a psychiatric outpatient population.

The DAPP-SF as a screener for personality disorder in a forensic setting.

PubMed

Spaans, Marleen; Rinne, Thomas; de Beurs, Edwin; Spinhoven, Philip

2015-01-01

Studies on the Dimensional Assessment of Personality Pathology-Short Form (DAPP-SF) have shown its ability to identify treatment-seeking patients with personality disorders. This study focuses on its screening potential for personality disorder in 89 criminal suspects (77 men, 12 women; M age = 37.0 years) undergoing residential pretrial psychological assessments in a high-security setting. It was expected that Structured Interview for DSM-IV Personality (SIDP-IV) criteria met for personality disorder(s) would be associated with higher DAPP-SF scores. A floor effect was found in DAPP-SF scores: The forensic population reported less personality pathology than the general population. Only moderate associations between DAPP-SF and SIDP-IV outcome were found. Receiver operating characteristic analysis showed that some DAPP-SF subscales did not exceed chance level in their ability to screen for personality disorders. It is concluded that the DAPP-SF has limited usefulness as a screener for personality disorders in a forensic pretrial setting. Alternative forensic screening instruments are presented.

Assessment of Semi-Structured Clinical Interview for Mobile Phone Addiction Disorder

PubMed Central

Alavi, Seyyed Salman; Jannatifard, Fereshteh; Mohammadi Kalhori, Soroush; Sepahbodi, Ghazal; BabaReisi, Mohammad; Sajedi, Sahar; Farshchi, Mojtaba; KhodaKarami, Rasul; Hatami Kasvaee, Vahid

2016-01-01

Objective: The Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision (DSM-IV-TR) classified mobile phone addiction disorder under “impulse control disorder not elsewhere classified”. This study surveyed the diagnostic criteria of DSM-IV-TR for the diagnosis of mobile phone addiction in correspondence with Iranian society and culture. Method: Two hundred fifty students of Tehran universities were entered into this descriptive-analytical and cross-sectional study. Quota sampling method was used. At first, semi- structured clinical interview (based on DSM-IV-TR) was performed for all the cases, and another specialist reevaluated the interviews. Data were analyzed using content validity, inter-scorer reliability (Kappa coefficient) and test-retest via SPSS18 software. Results: The content validity of the semi- structured clinical interview matched the DSM–IV-TR criteria for behavioral addiction. Moreover, their content was appropriate, and two items, including “SMS pathological use” and “High monthly cost of using the mobile phone” were added to promote its validity. Internal reliability (Kappa) and test–retest reliability were 0.55 and r = 0.4 (p<0. 01) respectively. Conclusion: The results of this study revealed that semi- structured diagnostic criteria of DSM-IV-TR are valid and reliable for diagnosing mobile phone addiction, and this instrument is an effective tool to diagnose this disorder. PMID:27437008

Predicting College Women's Career Plans: Instrumentality, Work, and Family

ERIC Educational Resources Information Center

Savela, Alexandra E.; O'Brien, Karen M.

2016-01-01

This study examined how college women's instrumentality and expectations about combining work and family predicted early career development variables. Specifically, 177 undergraduate women completed measures of instrumentality (i.e., traits such as ambition, assertiveness, and risk taking), willingness to compromise career for family, anticipated…

A critical appraisal of instruments to measure outcomes of interprofessional education.

PubMed

Oates, Matthew; Davidson, Megan

2015-04-01

Interprofessional education (IPE) is believed to prepare health professional graduates for successful collaborative practice. A range of instruments have been developed to measure the outcomes of IPE. An understanding of the psychometric properties of these instruments is important if they are to be used to measure the effectiveness of IPE. This review set out to identify instruments available to measure outcomes of IPE and collaborative practice in pre-qualification health professional students and to critically appraise the psychometric properties of validity, responsiveness and reliability against contemporary standards for instrument design. Instruments were selected from a pool of extant instruments and subjected to critical appraisal to determine whether they satisfied inclusion criteria. The qualitative and psychometric attributes of the included instruments were appraised using a checklist developed for this review. Nine instruments were critically appraised, including the widely adopted Readiness for Interprofessional Learning Scale (RIPLS) and the Interdisciplinary Education Perception Scale (IEPS). Validity evidence for instruments was predominantly based on test content and internal structure. Ceiling effects and lack of scale width contribute to the inability of some instruments to detect change in variables of interest. Limited reliability data were reported for two instruments. Scale development and scoring protocols were generally reported by instrument developers, but the inconsistent application of scoring protocols for some instruments was apparent. A number of instruments have been developed to measure outcomes of IPE in pre-qualification health professional students. Based on reported validity evidence and reliability data, the psychometric integrity of these instruments is limited. The theoretical test construction paradigm on which instruments have been developed may be contributing to the failure of some instruments to detect change in variables of interest following an IPE intervention. These limitations should be considered in any future research on instrument design. © 2015 John Wiley & Sons Ltd.

A Process Evaluation of Project Developmental Continuity. Interim Report IV, Volume I: Pilot Year Impact Study--Instrument Characteristics and Attrition Trends.

ERIC Educational Resources Information Center

Granville, Arthur C.; And Others

This interim report of a pilot year impact study on evaluation methodology is part of a series of documents on the evaluation of Project Developmental Continuity, a Head Start demonstration program aimed at promoting educational and developmental continuity between children's Head Start and primary school experiences. This report deals with…

Real Time Quality Control Methods for Cued EMI Data Collection

DTIC Science & Technology

2016-03-14

contents be construed as reflecting the official policy or position of the Department of Defense. Reference herein to any specific commercial product...This project evaluated the effectiveness of in-field quality control (QC) procedures during cued electromagnetic induction (EMI) data collection. The...electromagnetic induction ESTCP Environmental Security Technology Certification Program hr hour ISO Industry Standard Object IVS Instrument

77 FR 25457 - Applications for New Awards; Enhanced Assessment Instruments Grants Program-Enhanced Assessment...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-30

... priorities and one competitive preference priority. In accordance with 34 CFR 75.105(b)(2)(iv), absolute... priorities. Under 34 CFR 75.105(c)(3) we consider only applications that meet: (a) one or more of the... Title I and Title III of the ESEA; (4) Can be used, as appropriate, as one of multiple measures, to...

The Importance of Relying on the Manual: Scoring Error Variance in the WISC-IV Vocabulary Subtest

ERIC Educational Resources Information Center

Erdodi, Laszlo A.; Richard, David C. S.; Hopwood, Christopher

2009-01-01

Classical test theory assumes that ability level has no effect on measurement error. Newer test theories, however, argue that the precision of a measurement instrument changes as a function of the examinee's true score. Research has shown that administration errors are common in the Wechsler scales and that subtests requiring subjective scoring…

Interpretation of Endodontic File Length Adjustments Using Radiovisiography

DTIC Science & Technology

1993-01-01

periapical tissues would cause apical granulomas, and sometimes epithelial proliferation leading to cyst formation. They believed that better results...RVG) images. Comparisons were made between RVG images and conventional periapical radiographs. Maxillary and mandibular human cadaver sections with a...Biologic aspects of endodontics IV. Periapical tissue reactions to root-filled teeth whose canals had been instrumented short of their apices. Oral

40 CFR 65.104 - Instrument and sensory monitoring for leaks.

Code of Federal Regulations, 2013 CFR

2013-07-01

.... (i) Valves in gas/vapor service and in light liquid service shall be monitored pursuant to § 65.106(b). (ii) Pumps in light liquid service shall be monitored pursuant to § 65.107(b). (iii) Connectors in gas/vapor service and in light liquid service shall be monitored pursuant to § 65.108(b). (iv) Agitators in...

40 CFR 65.104 - Instrument and sensory monitoring for leaks.

Code of Federal Regulations, 2011 CFR

2011-07-01

.... (i) Valves in gas/vapor service and in light liquid service shall be monitored pursuant to § 65.106(b). (ii) Pumps in light liquid service shall be monitored pursuant to § 65.107(b). (iii) Connectors in gas/vapor service and in light liquid service shall be monitored pursuant to § 65.108(b). (iv) Agitators in...

77 FR 25463 - Applications for New Awards; Enhanced Assessment Instruments Grants Program-Enhanced Assessment...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-04-30

... consider only applications that meet one or more of the Statutory Priorities. These priorities are... matching. 3. Other: An application from a consortium of SEAs must designate one SEA as the fiscal agent. IV... more than 45 pages, using the following standards: A ``page'' is 8.5 x 11 , on one side only with 1...

The influence of lifestyle on cardiovascular risk factors. Analysis using a neural network.

PubMed

Gueli, Nicoló; Piccirillo, Gianfanco; Troisi, Giovanni; Cicconetti, Paolo; Meloni, Fortunato; Ettorre, Evaristo; Verico, Paola; D'Arcangelo, Enzo; Cacciafesta, Mauro

2005-01-01

The cardiovascular pathologies are the most common causes of death in the elderly patient. To single out the main risk factors in order to effectively prevent the onset of the disease, the authors experimented a special computerized tool, the neural network, that works out a mathematical relation that can obtain certain data (defined as output) as a function of other data (defined as input). Data were processed from a sample of 276 subjects of both sexes aged 26-69 years old. The output data were: high/low cholesterolemia, HDL cholesterol, triglyceridemia with respect to an established cut-off; the input data were: sex, age, build, weight, married/single, number of children, number of cigarettes smoked/day, amount of wine and number of cups of coffee. We conclude that: (i) a relationship exists, deduced from a neural network, between a set of input variables and a dichotomous output variable; (ii) this relationship can be expressed as a mathematical function; (iii) a neural network, having learned the data on a sufficiently large population, can provide valid predictive data for a single individual with a high probability (up to 93.33%) that the response it gives is correct. In this study, such a result is found for two of the three cardiovascular risk indicators considered (cholesterol and triglycerides); (iv) the repetition of the neural network analysis of the cases in question after a "pruning" operation provided a somewhat less good performance; (v) a statistical analysis conducted on those same cases has confirmed the existence of a strong relationship between the input and the output variables. Therefore the neural network is a valid instrument for providing predictive in a single subject on cardiovascular pathology risks.

Rationale for hedging initiatives: Empirical evidence from the energy industry

NASA Astrophysics Data System (ADS)

Dhanarajata, Srirajata

Theory offers different rationales for hedging including (i) financial distress and bankruptcy cost, (ii) capacity to capture attractive investment opportunities, (iii) information asymmetry, (iv) economy of scale, (v) substitution for hedging, (vi) managerial risk aversion, and (vii) convexity of tax schedule. The purpose of this dissertation is to empirically test the explanatory power of the first five theoretical rationales on hedging done by oil and gas exploration and production (E&P) companies. The level of hedging is measured by the percentage of production effectively hedged, calculated based on the concept of delta and delta-gamma hedging. I employ Tobit regression, principal components, and panel data analysis on dependent and raw independent variables. Tobit regression is applied due to the fact that the dependent variable used in the analysis is non-negative. Principal component analysis helps to reduce the dimension of explanatory variables while panel data analysis combines/pools the data that is a combination of time-series and cross-sectional. Based on the empirical results, leverage level is consistently found to be a significant factor on hedging activities, either due to an attempt to avoid financial distress by the firm, or an attempt to control agency cost by debtholders, or both. The effect of capital expenditures and discretionary cash flows are both indeterminable due possibly to a potential mismatch in timing of realized cash flow items and hedging decision. Firm size is found to be positively related to hedging supporting economy of scale hypothesis, which is introduced in past literature, as well as the argument that large firm usually are more sophisticated and should be more willing and more comfortable to use hedge instruments than smaller firms.

Technology Roadmap Instrumentation, Control, and Human-Machine Interface to Support DOE Advanced Nuclear Energy Programs

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

Donald D Dudenhoeffer; Burce P Hallbert

Instrumentation, Controls, and Human-Machine Interface (ICHMI) technologies are essential to ensuring delivery and effective operation of optimized advanced Generation IV (Gen IV) nuclear energy systems. In 1996, the Watts Bar I nuclear power plant in Tennessee was the last U.S. nuclear power plant to go on line. It was, in fact, built based on pre-1990 technology. Since this last U.S. nuclear power plant was designed, there have been major advances in the field of ICHMI systems. Computer technology employed in other industries has advanced dramatically, and computing systems are now replaced every few years as they become functionally obsolete. Functionalmore » obsolescence occurs when newer, more functional technology replaces or supersedes an existing technology, even though an existing technology may well be in working order.Although ICHMI architectures are comprised of much of the same technology, they have not been updated nearly as often in the nuclear power industry. For example, some newer Personal Digital Assistants (PDAs) or handheld computers may, in fact, have more functionality than the 1996 computer control system at the Watts Bar I plant. This illustrates the need to transition and upgrade current nuclear power plant ICHMI technologies.« less

Refinement of planetary protection policy for Mars missions

NASA Technical Reports Server (NTRS)

DeVincenzi, D. L.; Stabekis, P.; Barengoltz, J.

1996-01-01

Under existing COSPAR policy adopted in 1984, missions to Mars (landers, probes, and some orbiters) are designated as Category IV missions. As such, the procedures for implementing planetary protection requirements could include trajectory biasing, cleanrooms, bioload reduction, sterilization of hardware, and bioshields. In 1992, a U.S. National Research Council study recommended that controls on forward contamination of Mars be tied to specific mission objectives. The report recommended that Mars landers with life detection instruments be subject to at least Viking-level sterilization procedures for bioload reduction, while spacecraft (including orbiters) without life detection instruments be subject to at least Viking-level pre-sterilization procedures for bioload reduction but need not be sterilized. In light of this, it is proposed that the current policy's Category IV and its planetary protection requirements be divided into two sub-categories as follows: Category IVa, for missions comprising landers and probes without life detection experiments, which will meet a specified bioburden limit for exposed surfaces, and Category IVb, for landers and probes with life detection experiments, which will require sterilization of landed systems. In addition, Category III orbiter mission specifications are expanded to be consistent with these recommendations.

IV-VI semiconductor lasers for gas phase biomarker detection

NASA Astrophysics Data System (ADS)

McCann, Patrick; Namjou, Khosrow; Roller, Chad; McMillen, Gina; Kamat, Pratyuma

2007-09-01

A promising absorption spectroscopy application for mid-IR lasers is exhaled breath analysis where sensitive, selective, and speedy measurement of small gas phase biomarker molecules can be used to diagnose disease and monitor therapies. Many molecules such as nitric oxide, ethane, formaldehyde, acetaldehyde, acetone, carbonyl sulfide, and carbon disulfide have been connected to diseases or conditions such as asthma, oxidative stress, breast cancer, lung cancer, diabetes, organ transplant rejection, and schizophrenia. Measuring these and other, yet to be discovered, biomarker molecules in exhaled breath with mid-IR lasers offers great potential for improving health care since such tests are non-invasive, real-time, and do not require expensive consumables or chemical reagents. Motivated by these potential benefits, mid-IR laser spectrometers equipped with presently available cryogenically-cooled IV-VI lasers mounted in compact Stirling coolers have been developed for clinical research applications. This paper will begin with a description of the development of mid-IR laser instruments and their use in the largest known exhaled breath clinical study ever performed. It will then shift to a description of recent work on the development of new IV-VI semiconductor quantum well materials and laser fabrication methods that offer the promise of low power consumption (i.e. efficient) continuous wave emission at room temperature. Taken together, the demonstration of compelling clinical applications with large market opportunities and the clear identification of a viable pathway to develop low cost mid-IR laser instrumentation can create a renewed focus for future research and development efforts within the mid-IR materials and devices area.

Spanish adaptation of the NDSS (Nicotine Dependence Syndrome Scale) and assessment of nicotine-dependent individuals at primary care health centers in Spain.

PubMed

Becoña, Elisardo; López, Ana; Fernández del Río, Elena; Míguez, Ma Carmen; Castro, Josefina

2010-11-01

The availability of adequate instruments for the assessment of nicotine dependence is an important factor that is relevant in the area of tobacco addiction. In this study, we present a Spanish validation of the Nicotine Dependence Syndrome Scale (NDSS) (Shiffman, Waters, & Hickcox, 2004). The sample was composed ofpatients, all daily smokers, who visited their General Practitioner (GP) at five Primary Health Care Centers in different cities of Spain (N = 637). The results indicated adequate reliability for the general factor that assesses nicotine dependence (NDSS-Total) (Cronbach's alpha = .76). Factor analysis confirms the five factors of the original validation: Drive, Continuity, Stereotypy, Priority, and Tolerance. It must be noted that reliability is adequate for the first, and moderate or low for the rest. The NDSS-T and its scales correlate significantly with the Fagerström Test for Nicotine Dependence (FTND), with the nicotine dependence criteria of the Diagnostic and Statistical Manual of Mental Disorders IV (DSM-IV) as assessed through the Structured Clinical Interview for DSM-IV (SCID), with carbon monoxide levels in expired air (CO), and with the number of cigarettes smoked. The ROC curve indicates that the NDSS-T has a score of .79 which is under the curve (.69 for the FTND), thus the prediction of nicotine dependence is adequate. We conclude that this instrument is useful (in terms of its total score NDSS-T) for assessing nicotine dependence for Spanish smokers (in Spain), as has been found in other countries, language groups, and cultures.

Development of a new linearly variable edge filter (LVEF)-based compact slit-less mini-spectrometer

NASA Astrophysics Data System (ADS)

Mahmoud, Khaled; Park, Seongchong; Lee, Dong-Hoon

2018-02-01

This paper presents the development of a compact charge-coupled detector (CCD) spectrometer. We describe the design, concept and characterization of VNIR linear variable edge filter (LVEF)- based mini-spectrometer. The new instrument has been realized for operation in the 300 nm to 850 nm wavelength range. The instrument consists of a linear variable edge filter in front of CCD array. Low-size, light-weight and low-cost could be achieved using the linearly variable filters with no need to use any moving parts for wavelength selection as in the case of commercial spectrometers available in the market. This overview discusses the main components characteristics, the main concept with the main advantages and limitations reported. Experimental characteristics of the LVEFs are described. The mathematical approach to get the position-dependent slit function of the presented prototype spectrometer and its numerical de-convolution solution for a spectrum reconstruction is described. The performance of our prototype instrument is demonstrated by measuring the spectrum of a reference light source.

Exploration of an oculometer-based model of pilot workload

NASA Technical Reports Server (NTRS)

Krebs, M. J.; Wingert, J. W.; Cunningham, T.

1977-01-01

Potential relationships between eye behavior and pilot workload are discussed. A Honeywell Mark IIA oculometer was used to obtain the eye data in a fixed base transport aircraft simulation facility. The data were analyzed to determine those parameters of eye behavior which were related to changes in level of task difficulty of the simulated manual approach and landing on instruments. A number of trends and relationships between eye variables and pilot ratings were found. A preliminary equation was written based on the results of a stepwise linear regression. High variability in time spent on various instruments was related to differences in scanning strategy among pilots. A more detailed analysis of individual runs by individual pilots was performed to investigate the source of this variability more closely. Results indicated a high degree of intra-pilot variability in instrument scanning. No consistent workload related trends were found. Pupil diameter which had demonstrated a strong relationship to task difficulty was extensively re-exmained.

Using Bayesian variable selection to analyze regular resolution IV two-level fractional factorial designs

DOE PAGES

Chipman, Hugh A.; Hamada, Michael S.

2016-06-02

Regular two-level fractional factorial designs have complete aliasing in which the associated columns of multiple effects are identical. Here, we show how Bayesian variable selection can be used to analyze experiments that use such designs. In addition to sparsity and hierarchy, Bayesian variable selection naturally incorporates heredity . This prior information is used to identify the most likely combinations of active terms. We also demonstrate the method on simulated and real experiments.

Using Bayesian variable selection to analyze regular resolution IV two-level fractional factorial designs

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

Chipman, Hugh A.; Hamada, Michael S.

Regular two-level fractional factorial designs have complete aliasing in which the associated columns of multiple effects are identical. Here, we show how Bayesian variable selection can be used to analyze experiments that use such designs. In addition to sparsity and hierarchy, Bayesian variable selection naturally incorporates heredity . This prior information is used to identify the most likely combinations of active terms. We also demonstrate the method on simulated and real experiments.

Cesarean delivery rates among family physicians versus obstetricians: a population-based cohort study using instrumental variable methods

PubMed Central

Dawe, Russell Eric; Bishop, Jessica; Pendergast, Amanda; Avery, Susan; Monaghan, Kelly; Duggan, Norah; Aubrey-Bassler, Kris

2017-01-01

Background: Previous research suggests that family physicians have rates of cesarean delivery that are lower than or equivalent to those for obstetricians, but adjustments for risk differences in these analyses may have been inadequate. We used an econometric method to adjust for observed and unobserved factors affecting the risk of cesarean delivery among women attended by family physicians versus obstetricians. Methods: This retrospective population-based cohort study included all Canadian (except Quebec) hospital deliveries by family physicians and obstetricians between Apr. 1, 2006, and Mar. 31, 2009. We excluded women with multiple gestations, and newborns with a birth weight less than 500 g or gestational age less than 20 weeks. We estimated the relative risk of cesarean delivery using instrumental-variable-adjusted and logistic regression. Results: The final cohort included 776 299 women who gave birth in 390 hospitals. The risk of cesarean delivery was 27.3%, and the mean proportion of deliveries by family physicians was 26.9% (standard deviation 23.8%). The relative risk of cesarean delivery for family physicians versus obstetricians was 0.48 (95% confidence interval [CI] 0.41-0.56) with logistic regression and 1.27 (95% CI 1.02-1.57) with instrumental-variable-adjusted regression. Interpretation: Our conventional analyses suggest that family physicians have a lower rate of cesarean delivery than obstetricians, but instrumental variable analyses suggest the opposite. Because instrumental variable methods adjust for unmeasured factors and traditional methods do not, the large discrepancy between these estimates of risk suggests that clinical and/or sociocultural factors affecting the decision to perform cesarean delivery may not be accounted for in our database. PMID:29233843

A Systematic Review of Instruments to Identify Mental Health and Substance Use Problems Among Children in the Emergency Department.

PubMed

Newton, Amanda S; Soleimani, Amir; Kirkland, Scott W; Gokiert, Rebecca J

2017-05-01

Specialized instruments to screen and diagnose mental health problems in children and adolescents are not yet standard components of clinical assessments in emergency departments (EDs). We conducted a systematic review to investigate the psychometric properties, accuracy, and performance metrics of instruments used in the ED to identify pediatric mental health and substance use problems. We searched seven electronic databases and the gray literature for psychometric validation studies, diagnostic studies, and cohort studies that assessed any instrument to screen for or diagnose mental illness, emotional or behavioral problems, or substance use disorders. Studies had to include children and adolescents with mental health presentations or positive screens for substance use. Two reviewers independently screened studies for relevance and quality. Diagnostic study quality was assessed with the four QUADAS-2 domains. Psychometric study quality was assessed with published criteria for instrument reliability, validity, and usability. We present a descriptive analysis of the reported psychometric properties and diagnostic performance of instruments for each study. Of the 4,832 references screened, 14 met inclusion criteria. Included studies evaluate 18 instruments for identifying suicide risk (six studies), alcohol use disorders (six studies), mood disorders (one study), and ED decision making (need for assessment, admission; one study). Nine studies include a psychometric focus but quality varies, with no studies fully meeting criteria for reliability, validity, and usability. Seven studies examine diagnostic performance of an instrument, but no study has a low risk of bias for all QUADAS-2 domains. The HEADS-ED instrument has good inter-rater reliability (r = 0.785) for identifying general mental health problems and modest evidence for ruling in patients requiring hospital admission (positive likelihood ratio [LR+] = 6.30). Internal consistency (reliability) varies for instruments to screen for suicide risk (α = 0.46-0.97), and no instruments have both high sensitivity and high specificity. The Ask Suicide-Screening Questions (ASQ) is highly sensitive (98%) and has strong evidence for ruling out risk (negative likelihood ratio [LR-] = 0.04). Among screening instruments for alcohol use disorders, internal consistency is high for the consumption subscale of the Alcohol Use Disorders Identification Test (α = 0.83-0.88) and the Adolescent Drinking Index (α = 0.92). Both instruments also had sound internal validity. Diagnostically, a two-item instrument based on DSM-IV criteria is the most accurate in identifying patients with a disorder (area under the curve = 0.89) and has modest evidence for ruling in and out risk (LR+ = 8.80, LR- = 0.13). From available evidence, we recommend that ED clinicians use 1) the HEADS-ED to rule in ED admission among pediatric patients with visits for mental health care, 2) the ASQ to rule out suicide risk among pediatric patients with any visit type, and 3) the DSM-IV two-item instrument to rule in/rule out alcohol use disorders among pediatric patients currently using alcohol. These instruments require minimal to no training or time commitment. We also recommend that clinicians become familiar with each instrument's psychometric properties to understand the quality of the evidence base. In this review, however, we identify methodologic limitations in the evidence base. To develop a robust evidence base, additional research is necessary. © 2017 by the Society for Academic Emergency Medicine.

A summary of results from solar monitoring rocket flights

NASA Technical Reports Server (NTRS)

Duncan, C. H.

1981-01-01

Three rocket flights to measure the solar constant and provide calibration data for sensors aboard Nimbus 6, 7, and Solar Maximum Mission (SMM) spacecraft were accomplished. The values obtained by the rocket instruments for the solar constant in SI units are: 1367 w/sq m on 29 June 1976; 1372 w/sq m on 16 November 1978; and 1374 w/sq m on 22 May 1980. The uncertainty of the rocket measurements is + or - 0.5%. The values obtained by the Hickey-Frieden sensor on Nimbus 7 during the second and third flights was 1376 w/sq m. The value obtained by the Active Cavity Radiometer Model IV (ACR IV) on SMM during the flight was 1368 w/sq m.

Cost effectiveness of high-dose intravenous esomeprazole for peptic ulcer bleeding.

PubMed

Barkun, Alan N; Adam, Viviane; Sung, Joseph J Y; Kuipers, Ernst J; Mössner, Joachim; Jensen, Dennis; Stuart, Robert; Lau, James Y; Nauclér, Emma; Kilhamn, Jan; Granstedt, Helena; Liljas, Bengt; Lind, Tore

2010-01-01

Peptic ulcer bleeding (PUB) is a serious and sometimes fatal condition. The outcome of PUB strongly depends on the risk of rebleeding. A recent multinational placebo-controlled clinical trial (ClinicalTrials.gov identifier: NCT00251979) showed that high-dose intravenous (IV) esomeprazole, when administered after successful endoscopic haemostasis in patients with PUB, is effective in preventing rebleeding. From a policy perspective it is important to assess the cost efficacy of this benefit so as to enable clinicians and payers to make an informed decision regarding the management of PUB. Using a decision-tree model, we compared the cost efficacy of high-dose IV esomeprazole versus an approach of no-IV proton pump inhibitor for prevention of rebleeding in patients with PUB. The model adopted a 30-day time horizon and the perspective of third-party payers in the USA and Europe. The main efficacy variable was the number of averted rebleedings. Healthcare resource utilization costs (physician fees, hospitalizations, surgeries, pharmacotherapies) relevant for the management of PUB were also determined. Data for unit costs (prices) were primarily taken from official governmental sources, and data for other model assumptions were retrieved from the original clinical trial and the literature. After successful endoscopic haemostasis, patients received either high-dose IV esomeprazole (80 mg infusion over 30 min, then 8 mg/hour for 71.5 hours) or no-IV esomeprazole treatment, with both groups receiving oral esomeprazole 40 mg once daily from days 4 to 30. Rebleed rates at 30 days were 7.7% and 13.6%, respectively, for the high-dose IV esomeprazole and no-IV esomeprazole treatment groups (equating to a number needed to treat of 17 in order to prevent one additional patient from rebleeding). In the US setting, the average cost per patient for the high-dose IV esomeprazole strategy was $US14 290 compared with $US14 239 for the no-IV esomeprazole strategy (year 2007 values). For the European setting, Sweden and Spain were used as examples. In the Swedish setting the corresponding respective figures were Swedish kronor (SEK)67 862 ($US9220 at average 2006 interbank exchange rates) and SEK67 807 ($US9212) [year 2006 values]. Incremental cost-effectiveness ratios were $US866 and SEK938 ($US127), respectively, per averted rebleed when using IV esomeprazole. For the Spanish setting, the high-dose IV esomeprazole strategy was dominant (more effective and less costly than the no-IV esomeprazole strategy) [year 2008 values]. All results appeared robust to univariate/threshold sensitivity analysis, with high-dose IV esomeprazole becoming dominant with small variations in assumptions in the US and Swedish settings, while remaining a dominant approach in the Spanish scenario across a broad range of values. Sensitivity variables with prespecified ranges included lengths of stay and per diem assumptions, rebleeding rates and, in some cases, professional fees. In patients with PUB, high-dose IV esomeprazole after successful endoscopic haemostasis appears to improve outcomes at a modest increase in costs relative to a no-IV esomeprazole strategy from the US and Swedish third-party payer perspective. Whereas, in the Spanish setting, the high-dose IV esomeprazole strategy appeared dominant, being more effective and less costly.

Reconstructing pre-instrumental streamflow in Eastern Australia using a water balance approach

NASA Astrophysics Data System (ADS)

Tozer, C. R.; Kiem, A. S.; Vance, T. R.; Roberts, J. L.; Curran, M. A. J.; Moy, A. D.

2018-03-01

Streamflow reconstructions based on paleoclimate proxies provide much longer records than the short instrumental period records on which water resource management plans are currently based. In Australia there is a lack of in-situ high resolution paleoclimate proxy records, but remote proxies with teleconnections to Australian climate have utility in producing streamflow reconstructions. Here we investigate, via a case study for a catchment in eastern Australia, the novel use of an Antarctic ice-core based rainfall reconstruction within a Budyko-framework to reconstruct ∼1000 years of annual streamflow. The resulting streamflow reconstruction captures interannual to decadal variability in the instrumental streamflow, validating both the use of the ice core rainfall proxy record and the Budyko-framework method. In the preinstrumental era the streamflow reconstruction shows longer wet and dry epochs and periods of streamflow variability that are higher than observed in the instrumental era. Importantly, for both the instrumental record and preinstrumental reconstructions, the wet (dry) epochs in the rainfall record are shorter (longer) in the streamflow record and this non-linearity must be considered when inferring hydroclimatic risk or historical water availability directly from rainfall proxy records alone. These insights provide a better understanding of present infrastructure vulnerability in the context of past climate variability for eastern Australia. The streamflow reconstruction presented here also provides a better understanding of the range of hydroclimatic variability possible, and therefore represents a more realistic baseline on which to quantify the potential impacts of anthropogenic climate change on water security.

FDG-PET reproducibility in tumor-bearing mice: comparing a traditional SUV approach with a tumor-to-brain tissue ratio approach.

PubMed

Busk, Morten; Munk, Ole L; Jakobsen, Steen; Frøkiær, Jørgen; Overgaard, Jens; Horsman, Michael R

2017-05-01

Current [F-18]-fluorodeoxyglucose positron emission tomography (FDG-PET) procedures in tumor-bearing mice typically includes fasting, anesthesia, and standardized uptake value (SUV)-based quantification. Such procedures may be inappropriate for prolonged multiscan experiments. We hypothesize that normalization of tumor FDG retention relative to a suitable reference tissue may improve accuracy as this method may be less susceptible to uncontrollable day-to-day changes in blood glucose levels, physical activity, or unnoticed imperfect tail vein injections. Fed non-anesthetized tumor-bearing mice were administered FDG intravenously (i.v.) or intraperitoneally (i.p.) and PET scanned on consecutive days using a Mediso nanoScan PET/magnetic resonance imaging (MRI). Reproducibility of various PET-deduced measures of tumor FDG retention, including normalization to FDG signal in reference organs and a conventional SUV approach, was evaluated. Day-to-day variability in i.v. injected mice was lower when tumor FDG retention was normalized to brain signal (T/B), compared to normalization to other tissues or when using SUV-based normalization. Assessment of tissue radioactivity in dissected tissues confirmed the validity of PET-derived T/B ratios. Mean T/B and SUV values were similar in i.v. and i.p. administered animals, but SUV normalization was more robust in the i.p. group than in the i.v. group. Multimodality scanners allow tissue delineation and normalization of tumor FDG uptake relative to reference tissues. Normalization to brain, but not liver or kidney, improved scan reproducibility considerably and was superior to traditional SUV quantification in i.v. tracer-injected animals. Day-to-day variability in SUV's was lower in i.p. than in i.v. injected animals, and i.p. injections may therefore be a valuable alternative in prolonged rodent studies, where repeated vein injections are undesirable.

Comparison of APACHE III, APACHE IV, SAPS 3, and MPM0III and Influence of Resuscitation Status on Model Performance

PubMed Central

Gajic, Ognjen; Afessa, Bekele

2012-01-01

Background: There are few comparisons among the most recent versions of the major adult ICU prognostic systems (APACHE [Acute Physiology and Chronic Health Evaluation] IV, Simplified Acute Physiology Score [SAPS] 3, Mortality Probability Model [MPM]0III). Only MPM0III includes resuscitation status as a predictor. Methods: We assessed the discrimination, calibration, and overall performance of the models in 2,596 patients in three ICUs at our tertiary referral center in 2006. For APACHE and SAPS, the analyses were repeated with and without inclusion of resuscitation status as a predictor variable. Results: Of the 2,596 patients studied, 283 (10.9%) died before hospital discharge. The areas under the curve (95% CI) of the models for prediction of hospital mortality were 0.868 (0.854-0.880), 0.861 (0.847-0.874), 0.801 (0.785-0.816), and 0.721 (0.704-0.738) for APACHE III, APACHE IV, SAPS 3, and MPM0III, respectively. The Hosmer-Lemeshow statistics for the models were 33.7, 31.0, 36.6, and 21.8 for APACHE III, APACHE IV, SAPS 3, and MPM0III, respectively. Each of the Hosmer-Lemeshow statistics generated P values < .05, indicating poor calibration. Brier scores for the models were 0.0771, 0.0749, 0.0890, and 0.0932, respectively. There were no significant differences between the discriminative ability or the calibration of APACHE or SAPS with and without “do not resuscitate” status. Conclusions: APACHE III and IV had similar discriminatory capability and both were better than SAPS 3, which was better than MPM0III. The calibrations of the models studied were poor. Overall, models with more predictor variables performed better than those with fewer. The addition of resuscitation status did not improve APACHE III or IV or SAPS 3 prediction. PMID:22499827

Oral bioavailability of DN101, a concentrated formulation of calcitriol, in tumor-bearing dogs.

PubMed

Rassnick, Kenneth M; Muindi, Josephia R; Johnson, Candace S; Bailey, Dennis B; Trump, Donald L

2011-01-01

High-dose calcitriol (1,25-dihydroxyvitamin D(3)) has antineoplastic activity against a range of tumors and potentiates chemotherapeutic agents. In an earlier canine study, the MTD of intravenous (i.v.) calcitriol was 3.75 μg/kg, but polysorbate-associated hypersensitivity reactions were common. Use of commercially available oral calcitriol is limited by the absence of a formulation of suitable strength to allow administration of a reasonable number of caplets. This study evaluated the bioavailability of DN101, a concentrated oral calcitriol formulation specifically developed for anticancer applications. An open-label, single-dose, 2-way crossover study was conducted. Dogs randomly received a single 3.75 μg/kg dose of calcitriol either i.v. or oral (as DN101), followed by cisplatin (60 mg/m(2)). Three weeks later, the alternate form of calcitriol was given prior to another dose of cisplatin. Dogs received antihistamines and corticosteroids prior to both treatments. Food was withheld for 12 h before and after therapy. Serum calcitriol concentrations were measured by radioimmunoassay. Ten tumor-bearing dogs received both i.v. and oral calcitriol. Six dogs experienced hypersensitivity reactions during i.v. calcitriol. Sequence of calcitriol administration (day-1 vs. day-21) by either i.v. or oral routes had no effect on the major calcitriol pharmacokinetic parameters. Oral calcitriol resulted in significantly lower values for AUC (P = 0.05) and prolonged T (1/2) (P = 0.003) when compared to i.v. Calcitriol oral bioavailability was highly variable among dogs (mean ± SEM, 71 ± 12.6%). This study demonstrates that a high-dose formulation of calcitriol has a moderate bioavailability in dogs, but inter-individual variability in PK parameters is similar to that observed in people. With this bioavailability, serum concentrations of calcitriol that exhibit antitumor activity in a preclinical murine model were achieved in some dogs. Exploration of methods to minimize variation in calcitriol systemic exposure is warranted.

Ocean Current Effects on Marine Seismic Systems and Deployments.

DTIC Science & Technology

1982-01-01

UNCLASSIFIED NOROA-TN 132 N 44, i . 4- iv L~~~ Kr~4~ !jj A r qt4 : ~’~A71 I0 AII ABSTRACT Upper level and near bottom current measurements were made...indicated a variable yet generally slow 1 " current regime which posed minimal threat of cable entanglement. Current [ measurements made 5 m off bottom during...diameters a iv -ALI-- - 1. 1. Introduction Two types of physical oceanographic measurements were supplied by NORDA Code 331 In support of the March-April

The BALDER Beamline at the MAX IV Laboratory

NASA Astrophysics Data System (ADS)

Klementiev, K.; Norén, K.; Carlson, S.; Sigfridsson Clauss, K. G. V.; Persson, I.

2016-05-01

X-ray absorption spectroscopy (XAS) includes well-established methods to study the local structure around the absorbing element - extended X-ray absorption fine structure (EXAFS), and the effective oxidation number or to quantitatively determine the speciation of an element in a complex matrix - X-ray absorption near-edge structure (XANES). The increased brilliance and intensities available at the new generation of synchrotron light sources makes it possible to study, in-situ and in-operando, much more dilute systems with relevance for natural systems, as well as the micro-scale variability and dynamics of chemical reactions on the millisecond time-scale. The design of the BALDER beamline at the MAX IV Laboratory 3 GeV ring has focused on a high flux of photons in a wide energy range, 2.4-40 keV, where the K-edge is covered for the elements S to La, and the L 3-edge for all elements heavier than Sb. The overall design of the beamline will allow large flexibility in energy range, beam size and data collection time. The other focus of the beamline design is the possibility to perform multi-technique analyses on samples. Development of sample environment requires focus on implementation of auxiliary methods in such a way that techniques like Fourier transform infrared (FTIR) spectroscopy, UV-Raman spectroscopy, X-ray diffraction and/or mass spectrometry can be performed simultaneously as the XAS study. It will be a flexible system where different instruments can be plugged in and out depending on the needs for the particular investigation. Many research areas will benefit from the properties of the wiggler based light source and the capabilities to perform in-situ and in-operando measurements, for example environmental and geochemical sciences, nuclear chemistry, catalysis, materials sciences, and cultural heritage.

Performance of bias-correction methods for exposure measurement error using repeated measurements with and without missing data.

PubMed

Batistatou, Evridiki; McNamee, Roseanne

2012-12-10

It is known that measurement error leads to bias in assessing exposure effects, which can however, be corrected if independent replicates are available. For expensive replicates, two-stage (2S) studies that produce data 'missing by design', may be preferred over a single-stage (1S) study, because in the second stage, measurement of replicates is restricted to a sample of first-stage subjects. Motivated by an occupational study on the acute effect of carbon black exposure on respiratory morbidity, we compare the performance of several bias-correction methods for both designs in a simulation study: an instrumental variable method (EVROS IV) based on grouping strategies, which had been recommended especially when measurement error is large, the regression calibration and the simulation extrapolation methods. For the 2S design, either the problem of 'missing' data was ignored or the 'missing' data were imputed using multiple imputations. Both in 1S and 2S designs, in the case of small or moderate measurement error, regression calibration was shown to be the preferred approach in terms of root mean square error. For 2S designs, regression calibration as implemented by Stata software is not recommended in contrast to our implementation of this method; the 'problematic' implementation of regression calibration although substantially improved with use of multiple imputations. The EVROS IV method, under a good/fairly good grouping, outperforms the regression calibration approach in both design scenarios when exposure mismeasurement is severe. Both in 1S and 2S designs with moderate or large measurement error, simulation extrapolation severely failed to correct for bias. Copyright © 2012 John Wiley & Sons, Ltd.

The value of specialist care-infectious disease specialist referrals-why and for whom? A retrospective cohort study in a French tertiary hospital.

PubMed

Sasikumar, M; Boyer, S; Remacle-Bonnet, A; Ventelou, B; Brouqui, P

2017-04-01

This study evaluated the impact of infectious disease (ID) specialist referrals on outcomes in a tertiary hospital in France. This study tackled methodological constraints (selection bias, endogeneity) using instrumental variables (IV) methods in order to obtain a quasi-experimental design. In addition, we investigated whether certain characteristics of patients have a bearing on the impact of the intervention. We used the payments database and ID department files to obtain data for adults admitted with an ID diagnosis in the North Hospital, Marseille from 2012 to 2014. Comparable cohorts were obtained using coarsened exact matching and analysed using IV models. Mortality, readmissions, cost (payer perspective) and length of stay (LoS) were analysed. We recorded 15,393 (85.97%) stays, of which 2,159 (14.03%) benefited from IDP consultations. The intervention was seen to significantly lower the risk of inpatient mortality (marginal effect (M.E) = -19.06%) and cost of stay (average treatment effect (ATE) = - €5,573.39). The intervention group was seen to have a longer LoS (ATE = +4.95 days). The intervention conferred a higher reduction in mortality and cost for stays that experienced ICU care (mortality: odds ratio (OR) =0.09, M.E cost = -8,328.84 €) or had a higher severity of illness (mortality: OR=0.35, M.E cost = -1,331.92 €) and for patients aged between 50 and 65 years (mortality: OR=0.28, M.E cost = -874.78 €). This study shows that ID referrals are associated with lower risk of inpatient mortality and cost of stay, especially when targeted to certain subgroups.

Food Swamps Predict Obesity Rates Better Than Food Deserts in the United States.

PubMed

Cooksey-Stowers, Kristen; Schwartz, Marlene B; Brownell, Kelly D

2017-11-14

This paper investigates the effect of food environments, characterized as food swamps, on adult obesity rates. Food swamps have been described as areas with a high-density of establishments selling high-calorie fast food and junk food, relative to healthier food options. This study examines multiple ways of categorizing food environments as food swamps and food deserts, including alternate versions of the Retail Food Environment Index. We merged food outlet, sociodemographic and obesity data from the United States Department of Agriculture (USDA) Food Environment Atlas, the American Community Survey, and a commercial street reference dataset. We employed an instrumental variables (IV) strategy to correct for the endogeneity of food environments (i.e., that individuals self-select into neighborhoods and may consider food availability in their decision). Our results suggest that the presence of a food swamp is a stronger predictor of obesity rates than the absence of full-service grocery stores. We found, even after controlling for food desert effects, food swamps have a positive, statistically significant effect on adult obesity rates. All three food swamp measures indicated the same positive association, but reflected different magnitudes of the food swamp effect on rates of adult obesity ( p values ranged from 0.00 to 0.16). Our adjustment for reverse causality, using an IV approach, revealed a stronger effect of food swamps than would have been obtained by naïve ordinary least squares (OLS) estimates. The food swamp effect was stronger in counties with greater income inequality ( p < 0.05) and where residents are less mobile ( p < 0.01). Based on these findings, local government policies such as zoning laws simultaneously restricting access to unhealthy food outlets and incentivizing healthy food retailers to locate in underserved neighborhoods warrant consideration as strategies to increase health equity.

Food Swamps Predict Obesity Rates Better Than Food Deserts in the United States

PubMed Central

Cooksey-Stowers, Kristen; Schwartz, Marlene B.; Brownell, Kelly D.

2017-01-01

This paper investigates the effect of food environments, characterized as food swamps, on adult obesity rates. Food swamps have been described as areas with a high-density of establishments selling high-calorie fast food and junk food, relative to healthier food options. This study examines multiple ways of categorizing food environments as food swamps and food deserts, including alternate versions of the Retail Food Environment Index. We merged food outlet, sociodemographic and obesity data from the United States Department of Agriculture (USDA) Food Environment Atlas, the American Community Survey, and a commercial street reference dataset. We employed an instrumental variables (IV) strategy to correct for the endogeneity of food environments (i.e., that individuals self-select into neighborhoods and may consider food availability in their decision). Our results suggest that the presence of a food swamp is a stronger predictor of obesity rates than the absence of full-service grocery stores. We found, even after controlling for food desert effects, food swamps have a positive, statistically significant effect on adult obesity rates. All three food swamp measures indicated the same positive association, but reflected different magnitudes of the food swamp effect on rates of adult obesity (p values ranged from 0.00 to 0.16). Our adjustment for reverse causality, using an IV approach, revealed a stronger effect of food swamps than would have been obtained by naïve ordinary least squares (OLS) estimates. The food swamp effect was stronger in counties with greater income inequality (p < 0.05) and where residents are less mobile (p < 0.01). Based on these findings, local government policies such as zoning laws simultaneously restricting access to unhealthy food outlets and incentivizing healthy food retailers to locate in underserved neighborhoods warrant consideration as strategies to increase health equity. PMID:29135909

Pharmacodynamics and Pharmacokinetics of Morphine After Cardiac Surgery in Children With and Without Down Syndrome.

PubMed

Valkenburg, Abraham J; Calvier, Elisa A M; van Dijk, Monique; Krekels, Elke H J; O'Hare, Brendan P; Casey, William F; Mathôt, Ron A A; Knibbe, Catherijne A J; Tibboel, Dick; Breatnach, Cormac V

2016-10-01

To compare the pharmacodynamics and pharmacokinetics of IV morphine after cardiac surgery in two groups of children-those with and without Down syndrome. Prospective, single-center observational trial. PICU in a university-affiliated pediatric teaching hospital. Twenty-one children with Down syndrome and 17 without, 3-36 months old, scheduled for cardiac surgery with cardiopulmonary bypass. A loading dose of morphine (100 μg/kg) was administered after coming off bypass; thereafter, morphine infusion was commenced at 40 μg/kg/hr. During intensive care, nurses regularly assessed pain and discomfort with validated observational instruments (COMFORT-Behavior scale and Numeric Rating Scale-for pain). These scores guided analgesic and sedative treatment. Plasma samples were obtained for pharmacokinetic analysis. Median COMFORT-Behavior and Numeric Rating Scale scores were not statistically significantly different between the two groups. The median morphine infusion rate during the first 24 hours after surgery was 31.3 μg/kg/hr (interquartile range, 23.4-36.4) in the Down syndrome group versus 31.7 μg/kg/hr (interquartile range, 25.1-36.1) in the control group (p = 1.00). Population pharmacokinetic analysis revealed no statistically significant differences in any of the pharmacokinetic variables of morphine between the children with and without Down syndrome. This prospective trial showed that there are no differences in pharmacokinetics or pharmacodynamics between children with and without Down syndrome if pain and distress management is titrated to effect based on outcomes of validated assessment instruments. We have no evidence to adjust morphine dosing after cardiac surgery in children with Down syndrome.

Soil examination for a forensic trace evidence laboratory-Part 3: A proposed protocol for the effective triage and management of soil examinations.

PubMed

Woods, Brenda; Lennard, Chris; Kirkbride, K Paul; Robertson, James

2016-05-01

In the past, forensic soil examination was a routine aspect of forensic trace evidence examinations. The apparent need for soil examinations then went through a period of decline and with it the capability of many forensic laboratories to carry out soil examinations. In more recent years, interest in soil examinations has been renewed due-at least in part-to soil examinations contributing to some high profile investigations. However, much of this renewed interest has been in organisations with a primary interest in soil and geology rather than forensic science. We argue the need to reinstate soil examinations as a trace evidence sub-discipline within forensic science laboratories and present a pathway to support this aim. An examination procedure is proposed that includes: (i) appropriate sample collection and storage by qualified crime scene examiners; (ii) exclusionary soil examinations by trace evidence scientists within a forensic science laboratory; (iii) inclusionary soil examinations by trace evidence scientists within a forensic science laboratory; and (iv) higher-level examination of soils by specialist soil scientists and palynologists. Soil examinations conducted by trace evidence scientists will be facilitated if the examinations are conducted using the instrumentation routinely used by these examiners. Hence, the proposed examination protocol incorporates instrumentation in routine use in a forensic trace evidence laboratory. Finally, we report on an Australian soil scene variability study and a blind trial that demonstrate the utility of the proposed protocol for the effective triage and management of soil samples by forensic laboratories. Crown Copyright © 2016. Published by Elsevier Ireland Ltd. All rights reserved.

PM101: a cyclodextrin-based intravenous formulation of amiodarone devoid of adverse hemodynamic effects.

PubMed

Cushing, Daniel J; Kowey, Peter R; Cooper, Warren D; Massey, Bill W; Gralinski, Michael R; Lipicky, Raymond J

2009-04-01

Intravenous amiodarone (Amiodarone i.v.) is widely used to treat cardiac arrhythmias. The most frequent clinical adverse event associated with Amiodarone i.v. administration is systemic hypotension which has been attributed to the cosolvents used in the formulation, polysorbate 80 and benzyl alcohol. To minimize hypotension Amiodarone i.v. is diluted in 5% dextrose in water prior to administration and slowly infused. PM101 is a novel intravenous formulation that uses sulfobutylether-7-beta-cyclodextrin to solubilize amiodarone, and thus should be devoid of the untoward hemodynamic effects associated with polysorbate 80 and benzyl alcohol. Beagle dogs (n=7/group) were anesthetized with morphine and alpha-chloralose and instrumented to assess aortic blood pressure, cardiac output, cardiac contractility, and heart rate. Animals were treated with the U.S. approved human-equivalent loading dose (2.14 mg/kg) of Amiodarone i.v., PM101, and their respective vehicle controls. Administration of Amiodarone i.v. rapidly and significantly decreased mean aortic pressure, cardiac output, and cardiac contractility. A significant increase in heart rate was also observed as was a transient, but not significant, decrease in systemic vascular resistance. A similar pattern of rapid and significant hemodynamic changes was produced by the Amiodarone i.v. Vehicle (polysorbate 80/benzyl alcohol) alone. In marked contrast, PM101 and its vehicle produced no significant hemodynamic effects. This study provides a useful model for the continued search for a safe and effective intravenous amiodarone formulation devoid of the hypotensive risk associated with the current commercial formulation.

8 years of Solar Spectral Irradiance Variability Observed from the ISS with the SOLAR/SOLSPEC Instrument

NASA Astrophysics Data System (ADS)

Damé, Luc; Bolsée, David; Meftah, Mustapha; Irbah, Abdenour; Hauchecorne, Alain; Bekki, Slimane; Pereira, Nuno; Cessateur, Marchand; Gäel; , Marion; et al.

2016-10-01

Accurate measurements of Solar Spectral Irradiance (SSI) are of primary importance for a better understanding of solar physics and of the impact of solar variability on climate (via Earth's atmospheric photochemistry). The acquisition of a top of atmosphere reference solar spectrum and of its temporal and spectral variability during the unusual solar cycle 24 is of prime interest for these studies. These measurements are performed since April 2008 with the SOLSPEC spectro-radiometer from the far ultraviolet to the infrared (166 nm to 3088 nm). This instrument, developed under a fruitful LATMOS/BIRA-IASB collaboration, is part of the Solar Monitoring Observatory (SOLAR) payload, externally mounted on the Columbus module of the International Space Station (ISS). The SOLAR mission, with its actual 8 years duration, will cover almost the entire solar cycle 24. We present here the in-flight operations and performances of the SOLSPEC instrument, including the engineering corrections, calibrations and improved know-how procedure for aging corrections. Accordingly, a SSI reference spectrum from the UV to the NIR will be presented, together with its variability in the UV, as measured by SOLAR/SOLSPEC for 8 years. Uncertainties on these measurements and comparisons with other instruments will be briefly discussed.

Towards Student Instrumentation of Computer-Based Algebra Systems in University Courses

ERIC Educational Resources Information Center

Stewart, Sepideh; Thomas, Michael O. J.; Hannah, John

2005-01-01

There are many perceived benefits of using technology, such as computer algebra systems, in undergraduate mathematics courses. However, attaining these benefits sometimes proves elusive. Some of the key variables are the teaching approach and the student instrumentation of the technology. This paper considers the instrumentation of computer-based…

Instructional Interactions of Kindergarten Mathematics Classrooms: Validating a Direct Observation Instrument

ERIC Educational Resources Information Center

Doabler, Christian; Smolkowski, Keith; Fien, Hank; Kosty, Derek B.; Cary, Mari Strand

2010-01-01

In this paper, the authors report research focused directly on the validation of the Coding of Academic Teacher-Student interactions (CATS) direct observation instrument. They use classroom information gathered by the CATS instrument to better understand the potential mediating variables hypothesized to influence student achievement. Their study's…

26 CFR 1.1275-5 - Variable rate debt instruments.

Code of Federal Regulations, 2010 CFR

2010-04-01

... nonpublicly traded property. A debt instrument (other than a tax-exempt obligation) that would otherwise... variations in the cost of newly borrowed funds in the currency in which the debt instrument is denominated... on the yield of actively traded personal property (within the meaning of section 1092(d)(1)). (ii...

Power Sector Variability

EPA Pesticide Factsheets

This Technical Support Document (TSD) provides information in support of section IV.F, “Emission Reduction Requirements Including Variability”, in the preamble to the proposed Transport Rule (now known as the Cross-State Air Pollution Rule).

Planetary Protection Plan for an Antibody based instrument proposed for Mars2020

NASA Astrophysics Data System (ADS)

Smith, Heather; Parro, Víctor

The Signs Of Life Detector (SOLID) instrument is a high TRL level instrument proposed for the Mars 2020 instrument suite. In this presentation we describe the planetary protection instrument plan as if the instrument is classified as a life detection instrument compliant with Category IV(b) planetary protection mission requirements, NASA, ESA, and COSPAR policy. SOLID uses antibodies as a method for detecting organic and biomolecular components in soils. Due to the sensitive detection method, the scientific integrity of the instrument exceeds the planetary protection requirements. The instrument will be assembled and integrated in an ISO level 8 cleanroom or better (ISO 4 for the sample read out and fluidics components). Microbial reduction methods and assays employed are as follows: Wipe the outside and inside of the instrument with a mixture of isopropyl alcohol (70%) and water. Cell cultures will be the standard assay to determine enumeration of “viable” spores and other rapid assays such as LAL and ATP bioluminescence as secondary assays to verify the interior of the instrument is microbe free. SOLID’s design factors for contamination control include the following features: SOLID has the capability to heat the catchment tray to pyrolyze any Earth hitchhikers. There will also be an “air gap” of cm maintained between the sample acquisition device and the funnel inlet. This will prevent forward contamination of the sample collection device and reverse contamination of the detection unit. To mitigate false positives, SOLID will include anti-bodies for potential contaminants from organisms most commonly found in clean rooms. If selected for the Mars 2020 Rover, SOLID would be the first life detection instrument based on biomolecules sent by NASA, as such the planetary protection plan will set a precedence for future life detection instruments carrying biomolecules to other planetary bodies.

Comparison of the remaining dentin thickness in the root after hand and four rotary instrumentation techniques: an in vitro study.

PubMed

Rao, M S Rama; Shameem, Abdul; Nair, Rashmi; Ghanta, Sureshbabu; Thankachan, Rekha P; Issac, Johnson K

2013-07-01

The aim of the present study was to compare the remaining dental thickness (RDT) in the mesiobuccal root of mandibular first molars at 3 and 7 mm from the anatomic apex after instrumentation with ProTaper, light speed LSX, K3 and M2 and to compare with that of K-files. In this study, 60 extracted, untreated human mandibular first molars with fully formed apices, with curvature less than 35° and no root resorption were used. Prepared specimens were cut horizontally at 3 and 7 mm short of anatomic apex. The least dentin thickness from canal to external root surface was observed under 3× magnification and recorded using Clemax measuring tool and the sections were reassembled. Group I-instrumentation with ProTaper, group II-instrumentation with K3, group III-instrumentation with Light Speed LSX, group IV-instrumentation with M2 and group V- instrumentation with K-files and RDT was measured. Results showed that group V removed lesser amount of dentin compared to all other groups while all the three instrumentation techniques removed almost equal amount of dentin apically. Cleaning and shaping of the root canal space involves the elimination of pathogenic contents as well as attaining a uniform specific shape. However, the RDT following the use of various intraradicular procedures is an important factor to be considered as an iatrogenic cause that may result in root fracture. To avoid this, newer rotary instruments are being introduced.

Geophysics From Terrestrial Time-Variable Gravity Measurements

NASA Astrophysics Data System (ADS)

Van Camp, Michel; de Viron, Olivier; Watlet, Arnaud; Meurers, Bruno; Francis, Olivier; Caudron, Corentin

2017-12-01

In a context of global change and increasing anthropic pressure on the environment, monitoring the Earth system and its evolution has become one of the key missions of geosciences. Geodesy is the geoscience that measures the geometric shape of the Earth, its orientation in space, and gravity field. Time-variable gravity, because of its high accuracy, can be used to build an enhanced picture and understanding of the changing Earth. Ground-based gravimetry can determine the change in gravity related to the Earth rotation fluctuation, to celestial body and Earth attractions, to the mass in the direct vicinity of the instruments, and to vertical displacement of the instrument itself on the ground. In this paper, we review the geophysical questions that can be addressed by ground gravimeters used to monitor time-variable gravity. This is done in relation to the instrumental characteristics, noise sources, and good practices. We also discuss the next challenges to be met by ground gravimetry, the place that terrestrial gravimetry should hold in the Earth observation system, and perspectives and recommendations about the future of ground gravity instrumentation.

Effect of corruption on healthcare satisfaction in post-soviet nations: A cross-country instrumental variable analysis of twelve countries.

PubMed

Habibov, Nazim

2016-03-01

There is the lack of consensus about the effect of corruption on healthcare satisfaction in transitional countries. Interpreting the burgeoning literature on this topic has proven difficult due to reverse causality and omitted variable bias. In this study, the effect of corruption on healthcare satisfaction is investigated in a set of 12 Post-Socialist countries using instrumental variable regression on the sample of 2010 Life in Transition survey (N = 8655). The results indicate that experiencing corruption significantly reduces healthcare satisfaction. Copyright © 2016 The Author. Published by Elsevier Ltd.. All rights reserved.

Obstetric Facility Quality and Newborn Mortality in Malawi: A Cross-Sectional Study

PubMed Central

Fink, Günther; Nsona, Humphreys

2016-01-01

Background Ending preventable newborn deaths is a global health priority, but efforts to improve coverage of maternal and newborn care have not yielded expected gains in infant survival in many settings. One possible explanation is poor quality of clinical care. We assess facility quality and estimate the association of facility quality with neonatal mortality in Malawi. Methods and Findings Data on facility infrastructure as well as processes of routine and basic emergency obstetric care for all facilities in the country were obtained from 2013 Malawi Service Provision Assessment. Birth location and mortality for children born in the preceding two years were obtained from the 2013–2014 Millennium Development Goals Endline Survey. Facilities were classified as higher quality if they ranked in the top 25% of delivery facilities based on an index of 25 predefined quality indicators. To address risk selection (sicker mothers choosing or being referred to higher-quality facilities), we employed instrumental variable (IV) analysis to estimate the association of facility quality of care with neonatal mortality. We used the difference between distance to the nearest facility and distance to a higher-quality delivery facility as the instrument. Four hundred sixty-seven of the 540 delivery facilities in Malawi, including 134 rated as higher quality, were linked to births in the population survey. The difference between higher- and lower-quality facilities was most pronounced in indicators of basic emergency obstetric care procedures. Higher-quality facilities were located a median distance of 3.3 km further from women than the nearest delivery facility and were more likely to be in urban areas. Among the 6,686 neonates analyzed, the overall neonatal mortality rate was 17 per 1,000 live births. Delivery in a higher-quality facility (top 25%) was associated with a 2.3 percentage point lower newborn mortality (95% confidence interval [CI] -0.046, 0.000, p-value 0.047). These results imply a newborn mortality rate of 28 per 1,000 births at low-quality facilities and of 5 per 1,000 births at the top 25% of facilities, accounting for maternal and newborn characteristics. This estimate applies to newborns whose mothers would switch from a lower-quality to a higher-quality facility if one were more accessible. Although we did not find an indication of unmeasured associations between the instrument and outcome, this remains a potential limitation of IV analysis. Conclusions Poor quality of delivery facilities is associated with higher risk of newborn mortality in Malawi. A shift in focus from increasing utilization of delivery facilities to improving their quality is needed if global targets for further reductions in newborn mortality are to be achieved. PMID:27755547

Kinetic and isotherm analyses for thorium (IV) adsorptive removal from aqueous solutions by modified magnetite nanoparticle using response surface methodology (RSM)

NASA Astrophysics Data System (ADS)

Karimi, Mohammad; Milani, Saeid Alamdar; Abolgashemi, Hossein

2016-10-01

In this study, the ability and the adsorption capacity of magnetite/aminopropyltriethoxysilane/glutaraldehyde (Fe3O4/APTES/GA) adsorbent were evaluated for the adsorption of thorium (IV) ions from aqueous solutions. The influence of the several variables such as pH (1-5), Th (IV) initial concentration (50-300 mg L-1) and adsorbent concentration (1-5 g L-1) on the Th (IV) adsorption were investigated by response surface methodology (RSM). The results showed that the highest absorption capacity (q) was 107.23 mg g-1 with respect to pH = 4.5, initial concentration of 250 mg L-1 and adsorbent concentration of 1 g L-1 for 90 min. Modeling equilibrium sorption data with the Langmuir, Freundlich and Dubinin-Radushkevich models pointed out that the results were in good agreement with Langmuir model. The experimental kinetic data were well fitted to pseudo-second-order equation with R2 = 0.9739. Also thermodynamic parameters (ΔGo, ΔHo, ΔSo) declared that the Th (IV) adsorption was endothermic and spontaneous.

VLBI Analysis with the Multi-Technique Software GEOSAT

NASA Technical Reports Server (NTRS)

Kierulf, Halfdan Pascal; Andersen, Per-Helge; Boeckmann, Sarah; Kristiansen, Oddgeir

2010-01-01

GEOSAT is a multi-technique geodetic analysis software developed at Forsvarets Forsknings Institutt (Norwegian defense research establishment). The Norwegian Mapping Authority has now installed the software and has, together with Forsvarets Forsknings Institutt, adapted the software to deliver datum-free normal equation systems in SINEX format. The goal is to be accepted as an IVS Associate Analysis Center and to provide contributions to the IVS EOP combination on a routine basis. GEOSAT is based on an upper diagonal factorized Kalman filter which allows estimation of time variable parameters like the troposphere and clocks as stochastic parameters. The tropospheric delays in various directions are mapped to tropospheric zenith delay using ray-tracing. Meteorological data from ECMWF with a resolution of six hours is used to perform the ray-tracing which depends both on elevation and azimuth. Other models are following the IERS and IVS conventions. The Norwegian Mapping Authority has submitted test SINEX files produced with GEOSAT to IVS. The results have been compared with the existing IVS combined products. In this paper the outcome of these comparisons is presented.

Dynamic Architecture Computer

DTIC Science & Technology

1988-12-01

Figures ................................... v List of Tables ................................... vi I. Introduction ..................... 1 Background... 1 Problem ................................ 3 Scope .................................. 4 Approach...Collected Data on Variables ...... 136 Appendix D: Collected Data on Operations...............208 iv List of Figures Figure Page 2- 1 Keyword Search

Intraindividual neuropsychological test variability in healthy individuals with high average intelligence and educational attainment.

PubMed

Heyanka, Daniel J; Holster, Jessica L; Golden, Charles J

2013-08-01

Knowledge of patterns of neuropsychological performance among normal, healthy individuals is integral to the practice of clinical neuropsychology, because clinicians may not always account for intraindividual variability (IIV) before coming to diagnostic conclusions. The IIV was assessed among a sample of 46 healthy individuals with high average intelligence and educational attainment, utilizing a battery of neuropsychological tests, including the Wechsler Adult Intelligence Scale, Fourth Edition (WAIS-IV) and Wechsler Memory Scale, Fourth Edition (WMS-IV). The data indicated substantial variability in neurocognitive abilities. All participants were found to demonstrate scores considered impaired by at least 2 standard deviations (SDs). Despite adjusting for outliers, no participant produced a "normal" testing profile with an intraindividual maximum discrepancy (MD) of less than 1 SD in either direction. When WAIS-IV Full Scale IQ (FSIQ) was considered, participants generally demonstrated cognitive test scores ranging from 2 SDs less than to 1.5 SDs greater than their FSIQ. Furthermore, after demographic corrections, the majority (59%) of participants demonstrated at least 1 impaired cognitive test score, as defined by being 1 to 1.5 SDs below the mean. Overall, results substantiate the need for clinicians to consider FSIQ and educational attainment in interpretation of neuropsychological testing results, given the relevant commonality of "abnormal" test scores within this population. This may ultimately reduce the likelihood of making false-positive conclusions of impairment when educational attainment and intelligence are high, thus improving diagnostic accuracy.

Modeling and Error Analysis of a Superconducting Gravity Gradiometer.

DTIC Science & Technology

1979-08-01

fundamental limit to instrument - -1- sensitivity is the thermal noise of the sensor . For the gradiometer design outlined above, the best sensitivity...Mapoles at Stanford. Chapter IV determines the relation between dynamic range, the sensor Q, and the thermal noise of the cryogenic accelerometer. An...C.1 Accelerometer Optimization (1) Development and optimization of the loaded diaphragm sensor . (2) Determination of the optimal values of the

Post-Master's Education for Middle and Upper-Level Personnel in Libraries and Information Centers. Final Report, Phase I.

ERIC Educational Resources Information Center

Kortendick, James J.; Stone, Elizabeth W.

A major way of upgrading the profession of librarianship is through a post-master's education program. This data base for the curriculum development of such a program utilized two data-gathering instruments: (1) a questionnaire and (2) interviews. The data are presented under three-headings: (1) questionnaire results, Chapters III, IV, V and VI;…

Comparing the Diagnostic Accuracy of Six Potential Screening Instruments for Bipolar Disorder in Youths Aged 5 to 17 Years.

ERIC Educational Resources Information Center

Youngstrom, Eric A.; Findling, Robert L.; Calabrese, Joseph R.; Gracious, Barbara L.; Demeter, Christine; DelPorto Bedoya, Denise; Price, Megan

2004-01-01

Objective: To compare the diagnostic efficiency of six index tests as predictors of juvenile bipolar disorder in two large outpatient samples, aged 5 to 10 and 11 to 17 years, gathered from 1997 to 2002. Method: DSM-IV diagnosis was based on a semistructured diagnostic interview (Schedule for Affective Disorders and Schizophrenia for School-Age…

Measurement of psychological disorders using cognitive diagnosis models.

PubMed

Templin, Jonathan L; Henson, Robert A

2006-09-01

Cognitive diagnosis models are constrained (multiple classification) latent class models that characterize the relationship of questionnaire responses to a set of dichotomous latent variables. Having emanated from educational measurement, several aspects of such models seem well suited to use in psychological assessment and diagnosis. This article presents the development of a new cognitive diagnosis model for use in psychological assessment--the DINO (deterministic input; noisy "or" gate) model--which, as an illustrative example, is applied to evaluate and diagnose pathological gamblers. As part of this example, a demonstration of the estimates obtained by cognitive diagnosis models is provided. Such estimates include the probability an individual meets each of a set of dichotomous Diagnostic and Statistical Manual of Mental Disorders (text revision [DSM-IV-TR]; American Psychiatric Association, 2000) criteria, resulting in an estimate of the probability an individual meets the DSM-IV-TR definition for being a pathological gambler. Furthermore, a demonstration of how the hypothesized underlying factors contributing to pathological gambling can be measured with the DINO model is presented, through use of a covariance structure model for the tetrachoric correlation matrix of the dichotomous latent variables representing DSM-IV-TR criteria. Copyright 2006 APA

Audiological findings in children with mucopolysaccharidoses type i-iv.

PubMed

Vargas-Gamarra, María F; de Paula-Vernetta, Carlos; Vitoria Miñana, Isidro; Ibañez-Alcañiz, Isabel; Cavallé-Garrido, Laura; Alamar-Velazquez, Agustín

The aim of our study is to reflect hearing impairment of 23children diagnosed with mucopolysaccharidosis (MPS) typeI, II, III and IV. Retrospective study of the clinical, audiological and treatment (medical vs surgical) findings of 23children diagnosed with MPS typeI, II, III or IV followed at a Tertiary Referral Hospital between 1997 and 2015. Six cases of MPSI, 8 of MPSII, 4 of MPSIII and 5 of MPSIV were reviewed. 71.2% of patients had secretory otitis media (SOM) and 54% of patients had some type of hearing loss (HL). The behaviour of hearing loss was variable in each of the subgroups of MPS, finding greater involvement and variability in typesI and II. Children with MPS have a high risk of hearing loss. A significant percentage of transmissive HL progressing to mixed or sensorineural HL was observed. This was more common in typesI and II. Periodic follow up of these patients is mandatory because of hearing impairment and consequences for their development and quality of life. Copyright © 2016 Elsevier España, S.L.U. and Sociedad Española de Otorrinolaringología y Cirugía de Cabeza y Cuello. All rights reserved.

Ultraviolet studies of nova-like variables with the IUE

NASA Technical Reports Server (NTRS)

Guinan, E. F.

1983-01-01

KQ Mon is a new UX UMa-type nova-like variable. Optical spectra taken in 1978 reveal very shallow Balmer absorption lines and He I (wavelength 4471) absorption. There was no evidence of orbital variations but the appearance of the optical spectrum and the presence of low amplitude flickering suggested a strong similarity to CD-42 degrees 14462 (=V3885 Sgr) and other members of the UX UMa class. KQ Mon was observed at low dispersion with the IUE satellite. Six spectra taken with the short wavelength prime (SWP) camera are dominated by strong broad absorption lines due to N V, O I, Si III, Si IV, C IV, He II, N IV, and A1 III. There is little evidence of orbital phase modulation over the time baseline of the observations. Unlike UV observations of other UX UMa-type objects, KQ Mon exhibits no emission lines or P Cygni-type profiles and the velocity displacements appear to be smaller, suggesting the absence of a hot, high velocity wind characterizing other UX UMa stars. The relationship of KQ Mon to other UX UMa disk stars is discussed and a model is suggested to explain their observed properties and the lack of major outbursts.

Ocean Optics Protocols for Satellite Ocean Color Sensor Validation. Volume 4; Inherent Optical Properties: Instruments, Characterizations, Field Measurements and Data Analysis Protocols; Revised

NASA Technical Reports Server (NTRS)

Mueller, J. L. (Editor); Fargion, Giuletta S. (Editor); McClain, Charles R. (Editor); Pegau, Scott; Zaneveld, J. Ronald V.; Mitchell, B. Gregg; Kahru, Mati; Wieland, John; Stramska, Malgorzat

2003-01-01

This document stipulates protocols for measuring bio-optical and radiometric data for the Sensor Intercomparison and Merger for Biological and Interdisciplinary Oceanic Studies (SIMBIOS) Project activities and algorithm development. The document is organized into 6 separate volumes as Ocean Optics Protocols for Satellite Ocean Color Sensor Validation, Revision 4. Volume I: Introduction, Background and Conventions; Volume II: Instrument Specifications, Characterization and Calibration; Volume III: Radiometric Measurements and Data Analysis Methods; Volume IV: Inherent Optical Properties: Instruments, Characterization, Field Measurements and Data Analysis Protocols; Volume V: Biogeochemical and Bio-Optical Measurements and Data Analysis Methods; Volume VI: Special Topics in Ocean Optics Protocols and Appendices. The earlier version of Ocean Optics Protocols for Satellite Ocean Color Sensor Validation, Revision 3 (Mueller and Fargion 2002, Volumes 1 and 2) is entirely superseded by the six volumes of Revision 4 listed above.

Development of an instrumentation system for measurement of degradation of lubricating oil using optical fiber sensor

NASA Astrophysics Data System (ADS)

Laskar, S.; Bordoloi, S.

2016-01-01

This paper presents an instrumentation system to measure the degradation in lubricating oil using a bare, tapered and bent multi-mode optical fiber (BTBMOF) sensor probe and a temperature probe. The sensor system consists of (i) a bare, tapered and bent multi-mode optical fiber (BTBMOF) as optical sensor along with a laser source and a LDR (Light Dependent Resistor) as detector (ii) a temperature sensor (iii) a ATmega microcontroller based data acquisition system and (iv) a trained ANN for processing and calibration. The BTBMOF sensor and the temperature sensor are used to provide the measure of refractive index (RI) and the temperature of a lubricating oil sample. A microcontroller based instrumentation system with trained ANN algorithm has been developed to determine the degradation of the lubricating oil sample by sampling the readings of the optical fiber sensor, and the temperature sensor.

Derisking Renewable Energy Investment. A Framework to Support Policymakers in Selecting Public Instruments to Promote Renewable Energy Investment in Developing Countries

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

Waissbein, Oliver; Glemarec, Yannick; Bayraktar, Hande

2013-03-15

This report introduces an innovative framework to assist policymakers to quantitatively compare the impact of different public instruments to promote renewable energy. The report identifies the need to reduce the high financing costs for renewable energy in developing countries as an important task for policymakers acting today. The framework is structured in four stages: (i) risk environment, (ii) public instruments, (iii) levelised cost and (iv) evaluation. To illustrate how the framework can support decision-making in practice, the report presents findings from illustrative case studies in four developing countries. It then draws on these results to discuss possible directions for enhancingmore » public interventions to scale-up renewable energy investment. UNDP is also releasing a financial tool for policymakers to accompany the framework. The financial tool is available for download on the UNDP website.« less

Regularization Methods for High-Dimensional Instrumental Variables Regression With an Application to Genetical Genomics

PubMed Central

Lin, Wei; Feng, Rui; Li, Hongzhe

2014-01-01

In genetical genomics studies, it is important to jointly analyze gene expression data and genetic variants in exploring their associations with complex traits, where the dimensionality of gene expressions and genetic variants can both be much larger than the sample size. Motivated by such modern applications, we consider the problem of variable selection and estimation in high-dimensional sparse instrumental variables models. To overcome the difficulty of high dimensionality and unknown optimal instruments, we propose a two-stage regularization framework for identifying and estimating important covariate effects while selecting and estimating optimal instruments. The methodology extends the classical two-stage least squares estimator to high dimensions by exploiting sparsity using sparsity-inducing penalty functions in both stages. The resulting procedure is efficiently implemented by coordinate descent optimization. For the representative L1 regularization and a class of concave regularization methods, we establish estimation, prediction, and model selection properties of the two-stage regularized estimators in the high-dimensional setting where the dimensionality of co-variates and instruments are both allowed to grow exponentially with the sample size. The practical performance of the proposed method is evaluated by simulation studies and its usefulness is illustrated by an analysis of mouse obesity data. Supplementary materials for this article are available online. PMID:26392642

Estimating the causal influence of body mass index on risk of Parkinson disease: A Mendelian randomisation study

PubMed Central

Price, T. Ryan; De Pablo-Fernandez, Eduardo; Haycock, Philip C.; Schrag, Anette; Lees, Andrew J.; Hardy, John; Singleton, Andrew; Nalls, Mike A.; Pearce, Neil; Wood, Nicholas W.

2017-01-01

Background Both positive and negative associations between higher body mass index (BMI) and Parkinson disease (PD) have been reported in observational studies, but it has been difficult to establish causality because of the possibility of residual confounding or reverse causation. To our knowledge, Mendelian randomisation (MR)—the use of genetic instrumental variables (IVs) to explore causal effects—has not previously been used to test the effect of BMI on PD. Methods and findings Two-sample MR was undertaken using genome-wide association (GWA) study data. The associations between the genetic instruments and BMI were obtained from the GIANT consortium and consisted of the per-allele difference in mean BMI for 77 independent variants that reached genome-wide significance. The per-allele difference in log-odds of PD for each of these variants was estimated from a recent meta-analysis, which included 13,708 cases of PD and 95,282 controls. The inverse-variance weighted method was used to estimate a pooled odds ratio (OR) for the effect of a 5-kg/m2 higher BMI on PD. Evidence of directional pleiotropy averaged across all variants was sought using MR–Egger regression. Frailty simulations were used to assess whether causal associations were affected by mortality selection. A combined genetic IV expected to confer a lifetime exposure of 5-kg/m2 higher BMI was associated with a lower risk of PD (OR 0.82, 95% CI 0.69–0.98). MR–Egger regression gave similar results, suggesting that directional pleiotropy was unlikely to be biasing the result (intercept 0.002; p = 0.654). However, the apparent protective influence of higher BMI could be at least partially induced by survival bias in the PD GWA study, as demonstrated by frailty simulations. Other important limitations of this application of MR include the inability to analyse non-linear associations, to undertake subgroup analyses, and to gain mechanistic insights. Conclusions In this large study using two-sample MR, we found that variants known to influence BMI had effects on PD in a manner consistent with higher BMI leading to lower risk of PD. The mechanism underlying this apparent protective effect warrants further study. PMID:28609445

Early meteorological records from Latin-America and the Caribbean during the 18th and 19th centuries

NASA Astrophysics Data System (ADS)

Domínguez-Castro, Fernando; Vaquero, José Manuel; Gallego, María Cruz; Farrona, Ana María Marín; Antuña-Marrero, Juan Carlos; Cevallos, Erika Elizabeth; Herrera, Ricardo García; de La Guía, Cristina; Mejía, Raúl David; Naranjo, José Manuel; Del Rosario Prieto, María; Ramos Guadalupe, Luis Enrique; Seiner, Lizardo; Trigo, Ricardo Machado; Villacís, Marcos

2017-11-01

This paper provides early instrumental data recovered for 20 countries of Latin-America and the Caribbean (Argentina, Bahamas, Belize, Brazil, British Guiana, Chile, Colombia, Costa Rica, Cuba, Ecuador, France (Martinique and Guadalupe), Guatemala, Jamaica, Mexico, Nicaragua, Panama, Peru, Puerto Rico, El Salvador and Suriname) during the 18th and 19th centuries. The main meteorological variables retrieved were air temperature, atmospheric pressure, and precipitation, but other variables, such as humidity, wind direction, and state of the sky were retrieved when possible. In total, more than 300,000 early instrumental data were rescued (96% with daily resolution). Especial effort was made to document all the available metadata in order to allow further post-processing. The compilation is far from being exhaustive, but the dataset will contribute to a better understanding of climate variability in the region, and to enlarging the period of overlap between instrumental data and natural/documentary proxies.

Early meteorological records from Latin-America and the Caribbean during the 18th and 19th centuries.

PubMed

Domínguez-Castro, Fernando; Vaquero, José Manuel; Gallego, María Cruz; Farrona, Ana María Marín; Antuña-Marrero, Juan Carlos; Cevallos, Erika Elizabeth; Herrera, Ricardo García; de la Guía, Cristina; Mejía, Raúl David; Naranjo, José Manuel; Del Rosario Prieto, María; Ramos Guadalupe, Luis Enrique; Seiner, Lizardo; Trigo, Ricardo Machado; Villacís, Marcos

2017-11-14

This paper provides early instrumental data recovered for 20 countries of Latin-America and the Caribbean (Argentina, Bahamas, Belize, Brazil, British Guiana, Chile, Colombia, Costa Rica, Cuba, Ecuador, France (Martinique and Guadalupe), Guatemala, Jamaica, Mexico, Nicaragua, Panama, Peru, Puerto Rico, El Salvador and Suriname) during the 18th and 19th centuries. The main meteorological variables retrieved were air temperature, atmospheric pressure, and precipitation, but other variables, such as humidity, wind direction, and state of the sky were retrieved when possible. In total, more than 300,000 early instrumental data were rescued (96% with daily resolution). Especial effort was made to document all the available metadata in order to allow further post-processing. The compilation is far from being exhaustive, but the dataset will contribute to a better understanding of climate variability in the region, and to enlarging the period of overlap between instrumental data and natural/documentary proxies.

The impact of extracurricular activities participation on youth delinquent behaviors: An instrumental variables approach.

PubMed

Han, Sehee; Lee, Jonathan; Park, Kyung-Gook

2017-07-01

The purpose of this study was to examine the association between extracurricular activities (EA) participation and youth delinquency while tackling an endogeneity problem of EA participation. Using survey data of 12th graders in South Korea (n = 1943), this study employed an instrumental variables approach to address the self-selection problem of EA participation as the data for this study was based on an observational study design. We found a positive association between EA participation and youth delinquency based on conventional regression analysis. By contrast, we found a negative association between EA participation and youth delinquency based on an instrumental variables approach. These results indicate that caution should be exercised when we interpret the effect of EA participation on youth delinquency based on observational study designs. Copyright © 2017 The Foundation for Professionals in Services for Adolescents. Published by Elsevier Ltd. All rights reserved.