Forecasting high-priority infectious disease surveillance regions: a socioeconomic model.

PubMed

Chan, Emily H; Scales, David A; Brewer, Timothy F; Madoff, Lawrence C; Pollack, Marjorie P; Hoen, Anne G; Choden, Tenzin; Brownstein, John S

2013-02-01

Few researchers have assessed the relationships between socioeconomic inequality and infectious disease outbreaks at the population level globally. We use a socioeconomic model to forecast national annual rates of infectious disease outbreaks. We constructed a multivariate mixed-effects Poisson model of the number of times a given country was the origin of an outbreak in a given year. The dataset included 389 outbreaks of international concern reported in the World Health Organization's Disease Outbreak News from 1996 to 2008. The initial full model included 9 socioeconomic variables related to education, poverty, population health, urbanization, health infrastructure, gender equality, communication, transportation, and democracy, and 1 composite index. Population, latitude, and elevation were included as potential confounders. The initial model was pared down to a final model by a backwards elimination procedure. The dependent and independent variables were lagged by 2 years to allow for forecasting future rates. Among the socioeconomic variables tested, the final model included child measles immunization rate and telephone line density. The Democratic Republic of Congo, China, and Brazil were predicted to be at the highest risk for outbreaks in 2010, and Colombia and Indonesia were predicted to have the highest percentage of increase in their risk compared to their average over 1996-2008. Understanding socioeconomic factors could help improve the understanding of outbreak risk. The inclusion of the measles immunization variable suggests that there is a fundamental basis in ensuring adequate public health capacity. Increased vigilance and expanding public health capacity should be prioritized in the projected high-risk regions.

Draft genome assembly of the Bengalese finch, Lonchura striata domestica, a model for motor skill variability and learning

PubMed Central

Mets, David G; Brainard, Michael S

2018-01-01

Abstract Background Vocal learning in songbirds has emerged as a powerful model for sensorimotor learning. Neurobehavioral studies of Bengalese finch (Lonchura striata domestica) song, naturally more variable and plastic than songs of other finch species, have demonstrated the importance of behavioral variability for initial learning, maintenance, and plasticity of vocalizations. However, the molecular and genetic underpinnings of this variability and the learning it supports are poorly understood. Findings To establish a platform for the molecular analysis of behavioral variability and plasticity, we generated an initial draft assembly of the Bengalese finch genome from a single male animal to 151× coverage and an N50 of 3.0 MB. Furthermore, we developed an initial set of gene models using RNA-seq data from 8 samples that comprise liver, muscle, cerebellum, brainstem/midbrain, and forebrain tissue from juvenile and adult Bengalese finches of both sexes. Conclusions We provide a draft Bengalese finch genome and gene annotation to facilitate the study of the molecular-genetic influences on behavioral variability and the process of vocal learning. These data will directly support many avenues for the identification of genes involved in learning, including differential expression analysis, comparative genomic analysis (through comparison to existing avian genome assemblies), and derivation of genetic maps for linkage analysis. Bengalese finch gene models and sequences will be essential for subsequent manipulation (molecular or genetic) of genes and gene products, enabling novel mechanistic investigations into the role of variability in learned behavior. PMID:29618046

Draft genome assembly of the Bengalese finch, Lonchura striata domestica, a model for motor skill variability and learning.

PubMed

Colquitt, Bradley M; Mets, David G; Brainard, Michael S

2018-03-01

Vocal learning in songbirds has emerged as a powerful model for sensorimotor learning. Neurobehavioral studies of Bengalese finch (Lonchura striata domestica) song, naturally more variable and plastic than songs of other finch species, have demonstrated the importance of behavioral variability for initial learning, maintenance, and plasticity of vocalizations. However, the molecular and genetic underpinnings of this variability and the learning it supports are poorly understood. To establish a platform for the molecular analysis of behavioral variability and plasticity, we generated an initial draft assembly of the Bengalese finch genome from a single male animal to 151× coverage and an N50 of 3.0 MB. Furthermore, we developed an initial set of gene models using RNA-seq data from 8 samples that comprise liver, muscle, cerebellum, brainstem/midbrain, and forebrain tissue from juvenile and adult Bengalese finches of both sexes. We provide a draft Bengalese finch genome and gene annotation to facilitate the study of the molecular-genetic influences on behavioral variability and the process of vocal learning. These data will directly support many avenues for the identification of genes involved in learning, including differential expression analysis, comparative genomic analysis (through comparison to existing avian genome assemblies), and derivation of genetic maps for linkage analysis. Bengalese finch gene models and sequences will be essential for subsequent manipulation (molecular or genetic) of genes and gene products, enabling novel mechanistic investigations into the role of variability in learned behavior.

Study of process variables associated with manufacturing hermetically-sealed nickel-cadmium cells

NASA Technical Reports Server (NTRS)

Miller, L.

1972-01-01

The effort and results of a program to determine and study the critical process variables associated with the manufacture of aerospace, hermetically-sealed, nickel-cadmium cells are reported. During the period, the impregnation/polarization process variable study was brought to a close with the completion of a series of related experiments. The results of the experiments are summarized. During this period, a general characterization of cell separator materials was initiated. The major conclusions resulting from the characterization of materials are included.

The impact of social cognitive variables on the initial level of depression and recovery.

PubMed

Lam, D H; Green, B; Power, M J; Checkley, S

1994-10-01

Thirty-seven patients who fulfilled DSM-III-R criteria for Major Depressive Disorder were recruited for a double-blind controlled trial of Desipramine and placebo for 6 weeks. Data about social cognitive variables, including social adversities, investment in roles and goals, general social support and crisis support were collected. Crisis support had a moderating effect on the initial level of depression: the more crisis support the subjects had, the less depressed they were on recruitment. Initial level of depression, the experience of adversity and drugs all contributed significantly to recovery defined as Hamilton Rating for Depression less than 10 at week 6. When recovery was defined as Hamilton score halved or more than halved between week 2 and week 6, subjects' level of ideal emotional support, and whether they had experienced adversity in their most invested domains, contributed significantly to recovery, independent of any drug effects or the initial level of depression. The higher their level of ideal emotional support, the less was the chance of these subjects recovering. The findings of this study pointed to the importance of controlling for psycho-social variables in studies of response to treatment.

Associations between period 3 gene polymorphisms and sleep- /chronotype-related variables in patients with late-life insomnia.

PubMed

Mansour, Hader A; Wood, Joel; Chowdari, Kodavali V; Tumuluru, Divya; Bamne, Mikhil; Monk, Timothy H; Hall, Martica H; Buysse, Daniel J; Nimgaonkar, Vishwajit L

2017-01-01

A variable number tandem repeat polymorphism (VNTR) in the period 3 (PER3) gene has been associated with heritable sleep and circadian variables, including self-rated chronotypes, polysomnographic (PSG) variables, insomnia and circadian sleep-wake disorders. This report describes novel molecular and clinical analyses of PER3 VNTR polymorphisms to better define their functional consequences. As the PER3 VNTR is located in the exonic (protein coding) region of PER3, we initially investigated whether both alleles (variants) are transcribed into messenger RNA in human fibroblasts. The VNTR showed bi-allelic gene expression. We next investigated genetic associations in relation to clinical variables in 274 older adult Caucasian individuals. Independent variables included genotypes for the PER3 VNTR as well as a representative set of single nucleotide polymorphisms (SNPs) that tag common variants at the PER3 locus (linkage disequilibrium (LD) between genetic variants < 0.5). In order to comprehensively evaluate variables analyzed individually in prior analyses, dependent measures included PSG total sleep time and sleep latency, self-rated chronotype, estimated with the Composite Scale (CS), and lifestyle regularity, estimated using the social rhythm metric (SRM). Initially, genetic polymorphisms were individually analyzed in relation to each outcome variable using analysis of variance (ANOVA). Nominally significant associations were further tested using regression analyses that incorporated individual ANOVA-associated DNA variants as potential predictors and each of the selected sleep/circadian variables as outcomes. The covariates included age, gender, body mass index and an index of medical co-morbidity. Significant genetic associations with the VNTR were not detected with the sleep or circadian variables. Nominally significant associations were detected between SNP rs1012477 and CS scores (p = 0.003) and between rs10462021 and SRM (p = 0.047); rs11579477 and average delta power (p = 0.043) (analyses uncorrected for multiple comparisons). In conclusion, alleles of the VNTR are expressed at the transcript level and may have a functional effect in cells expressing the PER3 gene. PER3 polymorphisms had a modest impact on selected sleep/circadian variables in our sample, suggesting that PER3 is associated with sleep and circadian function beyond VNTR polymorphisms. Further replicate analyses in larger, independent samples are recommended.

VizieR Online Data Catalog: AAVSO International Variable Star Index VSX (Watson+, 2006-2014)

NASA Astrophysics Data System (ADS)

Watson, C.; Henden, A. A.; Price, A.

2017-05-01

This file contains Galactic stars known or suspected to be variable. It lists all stars that have an entry in the AAVSO International Variable Star Index (VSX; http://www.aavso.org/vsx). The database consisted initially of the General Catalogue of Variable Stars (GCVS) and the New Catalogue of Suspected Variables (NSV) and was then supplemented with a large number of variable star catalogues, as well as individual variable star discoveries or variables found in the literature. Effort has also been invested to update the entries with the latest information regarding position, type and period and to remove duplicates. The VSX database is being continually updated and maintained. For historical reasons some objects outside of the Galaxy have been included. (3 data files).

VizieR Online Data Catalog: AAVSO International Variable Star Index VSX (Watson+, 2006-2014)

NASA Astrophysics Data System (ADS)

Watson, C.; Henden, A. A.; Price, A.

2018-05-01

This file contains Galactic stars known or suspected to be variable. It lists all stars that have an entry in the AAVSO International Variable Star Index (VSX; http://www.aavso.org/vsx). The database consisted initially of the General Catalogue of Variable Stars (GCVS) and the New Catalogue of Suspected Variables (NSV) and was then supplemented with a large number of variable star catalogues, as well as individual variable star discoveries or variables found in the literature. Effort has also been invested to update the entries with the latest information regarding position, type and period and to remove duplicates. The VSX database is being continually updated and maintained. For historical reasons some objects outside of the Galaxy have been included. (3 data files).

Meeting the 2020 American Graduation Initiative (AGI) Goal of Increasing Postsecondary Graduation Rates and Completions: A Macro Perspective of Community College Student Educational Attainment

ERIC Educational Resources Information Center

Kotamraju, Pradeep; Blackman, Orville

2011-01-01

The paper uses the Integrated Postsecondary Education Data system (IPEDS) data to simulate the 2020 American Graduation Initiative (AGI) goal introduced by President Obama in the summer of 2009. We estimate community college graduation rates and completion numbers under different scenarios that include the following sets of variables: (a) internal…

Decoupled and linear quadratic regulator control of a large, flexible space antenna with an observer in the control loop

NASA Technical Reports Server (NTRS)

Hamer, H. A.; Johnson, K. G.; Young, J. W.

1985-01-01

An analysis is performed to compare decoupled and linear quadratic regulator (LQR) procedures for the control of a large, flexible space antenna. Control objectives involve: (1) commanding changes in the rigid-body modes, (2) nulling initial disturbances in the rigid-body modes, or (3) nulling initial disturbances in the first three flexible modes. Control is achieved with two three-axis control-moment gyros located on the antenna column. Results are presented to illustrate various effects on control requirements for the two procedures. These effects include errors in the initial estimates of state variables, variations in the type, number, and location of sensors, and deletions of state-variable estimates for certain flexible modes after control activation. The advantages of incorporating a time lag in the control feedback are also illustrated. In addition, the effects of inoperative-control situations are analyzed with regard to control requirements and resultant modal responses. Comparisons are included which show the effects of perfect state feedback with no residual modes (ideal case). Time-history responses are presented to illustrate the various effects on the control procedures.

BOREAS RSS-8 BIOME-BGC Model Simulations at Tower Flux Sites in 1994

NASA Technical Reports Server (NTRS)

Hall, Forrest G. (Editor); Nickeson, Jaime (Editor); Kimball, John

2000-01-01

BIOME-BGC is a general ecosystem process model designed to simulate biogeochemical and hydrologic processes across multiple scales (Running and Hunt, 1993). In this investigation, BIOME-BGC was used to estimate daily water and carbon budgets for the BOREAS tower flux sites for 1994. Carbon variables estimated by the model include gross primary production (i.e., net photosynthesis), maintenance and heterotrophic respiration, net primary production, and net ecosystem carbon exchange. Hydrologic variables estimated by the model include snowcover, evaporation, transpiration, evapotranspiration, soil moisture, and outflow. The information provided by the investigation includes input initialization and model output files for various sites in tabular ASCII format.

Reasons Associated with Total Thyroidectomy as Initial Surgical Management of an Indeterminate Thyroid Nodule.

PubMed

Angell, Trevor E; Vyas, Chirag M; Barletta, Justine A; Cibas, Edmund S; Cho, Nancy L; Doherty, Gerard M; Gawande, Atul A; Howitt, Brooke E; Krane, Jeffrey F; Marqusee, Ellen; Strickland, Kyle C; Alexander, Erik K; Moore, Francis D; Nehs, Matthew A

2018-05-01

Diagnostic hemithyroidectomy (HT) is the most widely recommended surgical procedure for a nodule with indeterminate cytology; however, additional details may make initial total thyroidectomy (TT) preferable. We sought to identify patient-specific factors (PSFs) associated with initial TT in patients with indeterminate thyroid nodules. Retrospective analysis of all patients with a thyroid nodule ≥ 1 cm and initial cytology of atypia of undetermined significance or suspicious for follicular neoplasm between 2012 and 2015 who underwent thyroidectomy. Medical records were reviewed for patient demographics, neck symptoms, nodule size, cytology, molecular test results, final histopathology, and additional PSFs influencing surgical management. Variables were analyzed to determine associations with the use of initial TT. Logistic regression analyses were performed to identify independent associations. Of 325 included patients, 182/325 (56.0%) had HT and 143/325 (44.0%) had TT. While patient age and sex, nodule size, and cytology result were not associated with initial treatment, five PSFs were associated with initial TT (p < 0.0001). These included contralateral nodules, hypothyroidism, fluorodeoxyglucose avidity on positron emission tomography scan, family history of thyroid cancer, and increased surgical risk. At least one PSF was present in 126/143 (88.1%) TT patients versus 47/182 (25.8%) HT patients (p < 0.0001). Multivariate logistic regression analysis demonstrated that these variables were the strongest independent predictor of TT (odds ratio 45.93, 95% confidence interval 18.80-112.23, p < 0.001). When surgical management of an indeterminate cytology thyroid nodule was performed, several PSFs were associated with a preference by surgeons and patients for initial TT, which may be useful to consider in making decisions on initial operative extent.

LSENS, a general chemical kinetics and sensitivity analysis code for gas-phase reactions: User's guide

NASA Technical Reports Server (NTRS)

Radhakrishnan, Krishnan; Bittker, David A.

1993-01-01

A general chemical kinetics and sensitivity analysis code for complex, homogeneous, gas-phase reactions is described. The main features of the code, LSENS, are its flexibility, efficiency and convenience in treating many different chemical reaction models. The models include static system, steady, one-dimensional, inviscid flow, shock initiated reaction, and a perfectly stirred reactor. In addition, equilibrium computations can be performed for several assigned states. An implicit numerical integration method, which works efficiently for the extremes of very fast and very slow reaction, is used for solving the 'stiff' differential equation systems that arise in chemical kinetics. For static reactions, sensitivity coefficients of all dependent variables and their temporal derivatives with respect to the initial values of dependent variables and/or the rate coefficient parameters can be computed. This paper presents descriptions of the code and its usage, and includes several illustrative example problems.

Capacity for Physical Activity Predicts Weight Loss After Roux-en-Y Gastric Bypass

PubMed Central

Hatoum, Ida J.; Stein, Heather K.; Merrifield, Benjamin F.; Kaplan, Lee M.

2014-01-01

Despite its overall excellent outcomes, weight loss after Roux-en-Y gastric bypass (RYGB) is highly variable. We conducted this study to identify clinical predictors of weight loss after RYGB. We reviewed charts from 300 consecutive patients who underwent RYGB from August 1999 to November 2002. Data collected included patient demographics, medical comorbidities, and diet history. Of the 20 variables selected for univariate analysis, 9 with univariate P values ≤ 0.15 were entered into a multivariable regression analysis. Using backward selection, covariates with P < 0.05 were retained. Potential confounders were added back into the model and assessed for effect on all model variables. Complete records were available for 246 of the 300 patients (82%). The patient characteristics were 75% female, 93% white, mean age of 45 years, and mean initial BMI of 52.3 kg/m2. One year after surgery, patients lost an average of 64.8% of their excess weight (s.d. = 20.5%). The multivariable regression analysis revealed that limited physical activity, higher initial BMI, lower educational level, diabetes, and decreased attendance at postoperative appointments had an adverse effect on weight loss after RYGB. A model including these five factors accounts for 41% of the observed variability in weight loss (adjusted r2 = 0.41). In this cohort, higher initial BMI and limited physical activity were the strongest predictors of decreased excess weight loss following RYGB. Limited physical activity may be particularly important because it represents an opportunity for potentially meaningful pre- and postsurgical intervention to maximize weight loss following RYGB. PMID:18997674

Input Variability Facilitates Unguided Subcategory Learning in Adults

PubMed Central

Eidsvåg, Sunniva Sørhus; Austad, Margit; Asbjørnsen, Arve E.

2015-01-01

Purpose This experiment investigated whether input variability would affect initial learning of noun gender subcategories in an unfamiliar, natural language (Russian), as it is known to assist learning of other grammatical forms. Method Forty adults (20 men, 20 women) were familiarized with examples of masculine and feminine Russian words. Half of the participants were familiarized with 32 different root words in a high-variability condition. The other half were familiarized with 16 different root words, each repeated twice for a total of 32 presentations in a high-repetition condition. Participants were tested on untrained members of the category to assess generalization. Familiarization and testing was completed 2 additional times. Results Only participants in the high-variability group showed evidence of learning after an initial period of familiarization. Participants in the high-repetition group were able to learn after additional input. Both groups benefited when words included 2 cues to gender compared to a single cue. Conclusions The results demonstrate that the degree of input variability can influence learners' ability to generalize a grammatical subcategory (noun gender) from a natural language. In addition, the presence of multiple cues to linguistic subcategory facilitated learning independent of variability condition. PMID:25680081

Input Variability Facilitates Unguided Subcategory Learning in Adults.

PubMed

Eidsvåg, Sunniva Sørhus; Austad, Margit; Plante, Elena; Asbjørnsen, Arve E

2015-06-01

This experiment investigated whether input variability would affect initial learning of noun gender subcategories in an unfamiliar, natural language (Russian), as it is known to assist learning of other grammatical forms. Forty adults (20 men, 20 women) were familiarized with examples of masculine and feminine Russian words. Half of the participants were familiarized with 32 different root words in a high-variability condition. The other half were familiarized with 16 different root words, each repeated twice for a total of 32 presentations in a high-repetition condition. Participants were tested on untrained members of the category to assess generalization. Familiarization and testing was completed 2 additional times. Only participants in the high-variability group showed evidence of learning after an initial period of familiarization. Participants in the high-repetition group were able to learn after additional input. Both groups benefited when words included 2 cues to gender compared to a single cue. The results demonstrate that the degree of input variability can influence learners' ability to generalize a grammatical subcategory (noun gender) from a natural language. In addition, the presence of multiple cues to linguistic subcategory facilitated learning independent of variability condition.

Forecasting High-Priority Infectious Disease Surveillance Regions: A Socioeconomic Model

PubMed Central

Chan, Emily H.; Scales, David A.; Brewer, Timothy F.; Madoff, Lawrence C.; Pollack, Marjorie P.; Hoen, Anne G.; Choden, Tenzin; Brownstein, John S.

2013-01-01

Background. Few researchers have assessed the relationships between socioeconomic inequality and infectious disease outbreaks at the population level globally. We use a socioeconomic model to forecast national annual rates of infectious disease outbreaks. Methods. We constructed a multivariate mixed-effects Poisson model of the number of times a given country was the origin of an outbreak in a given year. The dataset included 389 outbreaks of international concern reported in the World Health Organization's Disease Outbreak News from 1996 to 2008. The initial full model included 9 socioeconomic variables related to education, poverty, population health, urbanization, health infrastructure, gender equality, communication, transportation, and democracy, and 1 composite index. Population, latitude, and elevation were included as potential confounders. The initial model was pared down to a final model by a backwards elimination procedure. The dependent and independent variables were lagged by 2 years to allow for forecasting future rates. Results. Among the socioeconomic variables tested, the final model included child measles immunization rate and telephone line density. The Democratic Republic of Congo, China, and Brazil were predicted to be at the highest risk for outbreaks in 2010, and Colombia and Indonesia were predicted to have the highest percentage of increase in their risk compared to their average over 1996–2008. Conclusions. Understanding socioeconomic factors could help improve the understanding of outbreak risk. The inclusion of the measles immunization variable suggests that there is a fundamental basis in ensuring adequate public health capacity. Increased vigilance and expanding public health capacity should be prioritized in the projected high-risk regions. PMID:23118271

Predictors of Using a Microbicide-like Product Among Adolescent Girls

PubMed Central

Short, Mary B.; Succop, Paul A.; Ugueto, Ana M.; Rosenthal, Susan L.

2007-01-01

Purpose This study examined demographic, sexual history and weekly contextual variables, and perceptions about microbicides as predictors of microbicide-like product use. Methods Adolescent girls (N=208; 14-21 years) participated in a 6-month study in which they completed three face-to-face interviews and 24-weekly phone call interviews. Participants were given microbicide-like products (vaginal lubricants) and encouraged to use them with condoms when they had intercourse. Results Seventy-five percent of girls had a sexual opportunity to use the product. Using multi-variable logistic regression, the following variables independently predicted ever using the product: length of sexual experience, number of lifetime vaginal partners, and the Comparison to Condoms subscale on the Perceptions of Microbicides Scale. Using mixed model repeat measure linear regression, the following variables independently predicted frequency of use: week of the study, age, condom frequency prior to the study, and 3 subscales on the Perceptions of Microbicide Scale including the Comparison to Condoms subscale, the Negative Effects subscale, and the Pleasure subscale. Conclusion Most girls used the product, including those who were not protecting themselves with condoms. Girls’ initial perceptions regarding the product predicted initial use and frequency of use. Further research should evaluate the best methods for supporting the use of these products by young or sexually less experienced girls. PMID:17875461

The Canadian Hydrological Model (CHM): A multi-scale, variable-complexity hydrological model for cold regions

NASA Astrophysics Data System (ADS)

Marsh, C.; Pomeroy, J. W.; Wheater, H. S.

2016-12-01

There is a need for hydrological land surface schemes that can link to atmospheric models, provide hydrological prediction at multiple scales and guide the development of multiple objective water predictive systems. Distributed raster-based models suffer from an overrepresentation of topography, leading to wasted computational effort that increases uncertainty due to greater numbers of parameters and initial conditions. The Canadian Hydrological Model (CHM) is a modular, multiphysics, spatially distributed modelling framework designed for representing hydrological processes, including those that operate in cold-regions. Unstructured meshes permit variable spatial resolution, allowing coarse resolutions at low spatial variability and fine resolutions as required. Model uncertainty is reduced by lessening the necessary computational elements relative to high-resolution rasters. CHM uses a novel multi-objective approach for unstructured triangular mesh generation that fulfills hydrologically important constraints (e.g., basin boundaries, water bodies, soil classification, land cover, elevation, and slope/aspect). This provides an efficient spatial representation of parameters and initial conditions, as well as well-formed and well-graded triangles that are suitable for numerical discretization. CHM uses high-quality open source libraries and high performance computing paradigms to provide a framework that allows for integrating current state-of-the-art process algorithms. The impact of changes to model structure, including individual algorithms, parameters, initial conditions, driving meteorology, and spatial/temporal discretization can be easily tested. Initial testing of CHM compared spatial scales and model complexity for a spring melt period at a sub-arctic mountain basin. The meshing algorithm reduced the total number of computational elements and preserved the spatial heterogeneity of predictions.

On the generation of climate model ensembles

NASA Astrophysics Data System (ADS)

Haughton, Ned; Abramowitz, Gab; Pitman, Andy; Phipps, Steven J.

2014-10-01

Climate model ensembles are used to estimate uncertainty in future projections, typically by interpreting the ensemble distribution for a particular variable probabilistically. There are, however, different ways to produce climate model ensembles that yield different results, and therefore different probabilities for a future change in a variable. Perhaps equally importantly, there are different approaches to interpreting the ensemble distribution that lead to different conclusions. Here we use a reduced-resolution climate system model to compare three common ways to generate ensembles: initial conditions perturbation, physical parameter perturbation, and structural changes. Despite these three approaches conceptually representing very different categories of uncertainty within a modelling system, when comparing simulations to observations of surface air temperature they can be very difficult to separate. Using the twentieth century CMIP5 ensemble for comparison, we show that initial conditions ensembles, in theory representing internal variability, significantly underestimate observed variance. Structural ensembles, perhaps less surprisingly, exhibit over-dispersion in simulated variance. We argue that future climate model ensembles may need to include parameter or structural perturbation members in addition to perturbed initial conditions members to ensure that they sample uncertainty due to internal variability more completely. We note that where ensembles are over- or under-dispersive, such as for the CMIP5 ensemble, estimates of uncertainty need to be treated with care.

Program for solution of ordinary differential equations

NASA Technical Reports Server (NTRS)

Sloate, H.

1973-01-01

A program for the solution of linear and nonlinear first order ordinary differential equations is described and user instructions are included. The program contains a new integration algorithm for the solution of initial value problems which is particularly efficient for the solution of differential equations with a wide range of eigenvalues. The program in its present form handles up to ten state variables, but expansion to handle up to fifty state variables is being investigated.

The Quebec Rural Emergency Department Project: A Cross-Sectional Study of a Potential Two-Pronged Strategy in the Knowledge Transfer Process

PubMed Central

Poitras, Julien; Chauny, Jean-Marc; Lévesque, Jean-Frédéric; Ouimet, Mathieu; Dupuis, Gilles; Tanguay, Alain; Simard-Racine, Geneviève

2015-01-01

Introduction Health services research generates useful knowledge. Promotion of implementation of this knowledge in medical practice is essential. Prior to initiation of a major study on rural emergency departments (EDs), we deployed two knowledge transfer strategies designed to generate interest and engagement from potential knowledge users. The objective of this paper was to review: 1) a combined project launch and media press release strategy, and 2) a pre-study survey designed to survey potential knowledge users’ opinions on the proposed study variables. Materials and Methods We evaluated the impact of the project launch (presentation at two conferences hosted by key stakeholders) and media press release via a survey of participants/stakeholders and by calculating the number of media interview requests and reports generated. We used a pre-study survey to collect potential key stakeholder’ opinions on the study variables. Results Twenty-one of Quebec’s 26 rural EDs participated in the pre-study survey (81% participation rate). The press release about the study generated 51 press articles and 20 media request for interviews, and contributed to public awareness of a major rural research initiative. In the pre-study survey, thirteen participants (46%) mentioned prior knowledge of the research project. Results from the pre-study survey revealed that all of the potential study variables were considered to be relevant for inclusion in the research project. Respondents also proposed additional variables of interest, including factors promoting retention of human resources. Conclusions The present study demonstrated the potential utility of a two-pronged knowledge transfer strategy, including a combined formal launch and press release, and a pre-study survey designed to ensure that the included variables were of interest to participants and stakeholders. PMID:25849328

Experimental validation of plastic constitutive hardening relationship based upon the direction of the Net Burgers Density Vector

NASA Astrophysics Data System (ADS)

Sarac, Abdulhamit; Kysar, Jeffrey W.

2018-02-01

We present a new methodology for experimental validation of single crystal plasticity constitutive relationships based upon spatially resolved measurements of the direction of the Net Burgers Density Vector, which we refer to as the β-field. The β-variable contains information about the active slip systems as well as the ratios of the Geometrically Necessary Dislocation (GND) densities on the active slip systems. We demonstrate the methodology by comparing single crystal plasticity finite element simulations of plane strain wedge indentations into face-centered cubic nickel to detailed experimental measurements of the β-field. We employ the classical Peirce-Asaro-Needleman (PAN) hardening model in this study due to the straightforward physical interpretation of its constitutive parameters that include latent hardening ratio, initial hardening modulus and the saturation stress. The saturation stress and the initial hardening modulus have relatively large influence on the β-variable compared to the latent hardening ratio. A change in the initial hardening modulus leads to a shift in the boundaries of plastic slip sectors with the plastically deforming region. As the saturation strength varies, both the magnitude of the β-variable and the boundaries of the plastic slip sectors change. We thus demonstrate that the β-variable is sensitive to changes in the constitutive parameters making the variable suitable for validation purposes. We identify a set of constitutive parameters that are consistent with the β-field obtained from the experiment.

Infection with multidrug-resistant gram-negative bacteria in a pediatric oncology intensive care unit: risk factors and outcomes.

PubMed

Costa, Patrícia de Oliveira; Atta, Elias Hallack; Silva, André Ricardo Araújo da

2015-01-01

This study aimed at evaluating the predictors and outcomes associated with multidrug-resistant gram-negative bacterial (MDR-GNB) infections in an oncology pediatric intensive care unit (PICU). Data were collected relating to all episodes of GNB infection that occurred in a PICU between January of 2009 and December of 2012. GNB infections were divided into two groups for comparison: (1) infections attributed to MDR-GNB and (2) infections attributed to non-MDR-GNB. Variables of interest included age, gender, presence of solid tumor or hematologic disease, cancer status, central venous catheter use, previous Pseudomonas aeruginosa infection, healthcare-associated infection, neutropenia in the preceding 7 days, duration of neutropenia, length of hospital stay before ICU admission, length of ICU stay, and the use of any of the following in the previous 30 days: antimicrobial agents, corticosteroids, chemotherapy, or radiation therapy. Other variables included initial appropriate antimicrobial treatment, definitive inadequate antimicrobial treatment, duration of appropriate antibiotic use, time to initiate adequate antibiotic therapy, and the 7- and 30-day mortality. Multivariate logistic regression analyses showed significant relationships between MDR-GNB and hematologic diseases (odds ratio [OR] 5.262; 95% confidence interval [95% CI] 1.282-21.594; p=0.021) and healthcare-associated infection (OR 18.360; 95% CI 1.778-189.560; p=0.015). There were significant differences between MDR-GNB and non-MDR-GNB patients for the following variables: inadequate initial empirical antibiotic therapy, time to initiate adequate antibiotic treatment, and inappropriate antibiotic therapy. Hematologic malignancy and healthcare-associated infection were significantly associated with MDR-GNB infection in this sample of pediatric oncology patients. Copyright © 2015 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. All rights reserved.

Resource utilization in home health care: results of a prospective study.

PubMed

Trisolini, M G; Thomas, C P; Cashman, S B; Payne, S M

1994-01-01

Resource utilization in home health care has become an issue of concern due to rising costs and recent initiatives to develop prospective payment systems for home health care. A number of issues remain unresolved for the development of prospective reimbursement in this sector, including the types of variables to be included as payment variables and appropriate measures of resource use. This study supplements previous work on home health case-mix by analyzing the factors affecting one aspect of resource use for skilled nursing visits--visit length--and explores the usefulness of several specially collected variables which are not routinely available in administrative records. A data collection instrument was developed with a focus group of skilled nurses, identifying a range of variables hypothesized to affect visit length. Five categories of variables were studied using multiple regression analysis: provider-related; patient's socio-economic status; patient's clinical status; patient's support services; and visit-specific. The final regression model identifies 9 variables which significantly affect visit time. Five of the 9 are visit-specific variables, a significant finding since these are not routinely collected. Case-mix systems which include visit time as a measure of resource use will need to investigate visit-specific variables, as this study indicates they could have the largest influence on visit time. Two other types of resources used in home health care, supplies and security drivers, were also investigated in less detail.

Pharmacokinetics, pharmacodynamics, and pharmacogenetics of hydroxyurea treatment for children with sickle cell anemia

PubMed Central

Despotovic, Jenny M.; Mortier, Nicole A.; Flanagan, Jonathan M.; He, Jin; Smeltzer, Matthew P.; Kimble, Amy C.; Aygun, Banu; Wu, Song; Howard, Thad; Sparreboom, Alex

2011-01-01

Hydroxyurea therapy has proven laboratory and clinical efficacies for children with sickle cell anemia (SCA). When administered at maximum tolerated dose (MTD), hydroxyurea increases fetal hemoglobin (HbF) to levels ranging from 10% to 40%. However, interpatient variability of percentage of HbF (%HbF) response is high, MTD itself is variable, and accurate predictors of hydroxyurea responses do not currently exist. HUSTLE (NCT00305175) was designed to provide first-dose pharmacokinetics (PK) data for children with SCA initiating hydroxyurea therapy, to investigate pharmacodynamics (PD) parameters, including HbF response and MTD after standardized dose escalation, and to evaluate pharmacogenetics influences on PK and PD parameters. For 87 children with first-dose PK studies, substantial interpatient variability was observed, plus a novel oral absorption phenotype (rapid or slow) that influenced serum hydroxyurea levels and total hydroxyurea exposure. PD responses in 174 subjects were robust and similar to previous cohorts; %HbF at MTD was best predicted by 5 variables, including baseline %HbF, whereas MTD was best predicted by 5 variables, including serum creatinine. Pharmacogenetics analysis showed single nucleotide polymorphisms influencing baseline %HbF, including 5 within BCL11A, but none influencing MTD %HbF or dose. Accurate prediction of hydroxyurea treatment responses for SCA remains a worthy but elusive goal. PMID:21876119

Impact of Exposure to Childhood Maltreatment on Transitions to Alcohol Dependence in Women and Men.

PubMed

Oberleitner, Lindsay M S; Smith, Philip H; Weinberger, Andrea H; Mazure, Carolyn M; McKee, Sherry A

2015-11-01

Childhood maltreatment decreases age of first use and speeds the transition from first use to dependence (i.e., telescoping) for alcohol use, however, it is currently unknown whether this influence is the same for men and women. Analyses were conducted with the National Epidemiologic Survey on Alcohol and Related Conditions (n = 34,653). Outcome variables included age of alcohol initiation and time to onset of Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition alcohol dependence. Predictor variables included gender and childhood maltreatment. Linear and Poisson regression analyses were conducted. Results demonstrated that in regard to age of drinking initiation, individuals who experienced childhood maltreatment initiated 1 year earlier than those without maltreatment, however, there was no interaction of this relationship with gender. Regarding the time to dependence, it was found that women who experienced childhood maltreatment demonstrated telescoping (shorter time between onset and dependence) compared to women without maltreatment and men (both with and without maltreatment). Women with a history of childhood maltreatment are particularly vulnerable to an accelerated time from initiation of alcohol use until dependence, a pattern indicative of increased negative alcohol-related outcomes. Findings highlight the need for development of gender-specific prevention efforts and behavioral treatments to aid in early intervention of problematic alcohol use in women. © The Author(s) 2015.

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.

The Mediator complex: a central integrator of transcription

PubMed Central

Allen, Benjamin L.; Taatjes, Dylan J.

2016-01-01

The RNA polymerase II (pol II) enzyme transcribes all protein-coding and most non-coding RNA genes and is globally regulated by Mediator, a large, conformationally flexible protein complex with variable subunit composition (for example, a four-subunit CDK8 module can reversibly associate). These biochemical characteristics are fundamentally important for Mediator's ability to control various processes important for transcription, including organization of chromatin architecture and regulation of pol II pre-initiation, initiation, re-initiation, pausing, and elongation. Although Mediator exists in all eukaryotes, a variety of Mediator functions appear to be specific to metazoans, indicative of more diverse regulatory requirements. PMID:25693131

Ecological niche modeling for a cultivated plant species: a case study on taro (Colocasia esculenta) in Hawaii.

PubMed

Kodis, Mali'o; Galante, Peter; Sterling, Eleanor J; Blair, Mary E

2018-04-26

Under the threat of ongoing and projected climate change, communities in the Pacific Islands face challenges of adapting culture and lifestyle to accommodate a changing landscape. Few models can effectively predict how biocultural livelihoods might be impacted. Here, we examine how environmental and anthropogenic factors influence an ecological niche model (ENM) for the realized niche of cultivated taro (Colocasia esculenta) in Hawaii. We created and tuned two sets of ENMs: one using only environmental variables, and one using both environmental and cultural characteristics of Hawaii. These models were projected under two different Intergovernmental Panel on Climate Change (IPCC) Representative Concentration Pathways (RCPs) for 2070. Models were selected and evaluated using average omission rate and area under the receiver operating characteristic curve (AUC). We compared optimal model predictions by comparing the percentage of taro plots predicted present and measured ENM overlap using Schoener's D statistic. The model including only environmental variables consisted of 19 Worldclim bioclimatic variables, in addition to slope, altitude, distance to perennial streams, soil evaporation, and soil moisture. The optimal model with environmental variables plus anthropogenic features also included a road density variable (which we assumed as a proxy for urbanization) and a variable indicating agricultural lands of importance to the state of Hawaii. The model including anthropogenic features performed better than the environment-only model based on omission rate, AUC, and review of spatial projections. The two models also differed in spatial projections for taro under anticipated future climate change. Our results demonstrate how ENMs including anthropogenic features can predict which areas might be best suited to plant cultivated species in the future, and how these areas could change under various climate projections. These predictions might inform biocultural conservation priorities and initiatives. In addition, we discuss the incongruences that arise when traditional ENM theory is applied to species whose distribution has been significantly impacted by human intervention, particularly at a fine scale relevant to biocultural conservation initiatives. © 2018 by the Ecological Society of America.

Human exploration of space and power development

NASA Technical Reports Server (NTRS)

Cohen, Aaron

1991-01-01

Reasons for mounting the Space Exploration Initiative, the variables facing U.S. planners, and the developmental technologies that will be needed to support this initiative are discussed. The three more advanced technological approaches in the field of power generation described include a lunar-based solar power system, a geosynchronous-based earth orbit solar power satellite system, and the utilization of helium-3/deuterium fusion reaction to create a nuclear fuel cycle. It is noted that the major elements of the SEI will include a heavy-lift launch vehicle, a transfer vehicle and a descent/ascent vehicle for use on lunar missions and adaptable to Mars exploration.

Variable Selection for Support Vector Machines in Moderately High Dimensions

PubMed Central

Zhang, Xiang; Wu, Yichao; Wang, Lan; Li, Runze

2015-01-01

Summary The support vector machine (SVM) is a powerful binary classification tool with high accuracy and great flexibility. It has achieved great success, but its performance can be seriously impaired if many redundant covariates are included. Some efforts have been devoted to studying variable selection for SVMs, but asymptotic properties, such as variable selection consistency, are largely unknown when the number of predictors diverges to infinity. In this work, we establish a unified theory for a general class of nonconvex penalized SVMs. We first prove that in ultra-high dimensions, there exists one local minimizer to the objective function of nonconvex penalized SVMs possessing the desired oracle property. We further address the problem of nonunique local minimizers by showing that the local linear approximation algorithm is guaranteed to converge to the oracle estimator even in the ultra-high dimensional setting if an appropriate initial estimator is available. This condition on initial estimator is verified to be automatically valid as long as the dimensions are moderately high. Numerical examples provide supportive evidence. PMID:26778916

Factors predicting Behavior Management Problems during Initial Dental Examination in Children Aged 2 to 8 Years

PubMed Central

Kumar, Dipanshu; Anand, Ashish; Mittal, Vipula; Singh, Aparna; Aggarwal, Nidhi

2017-01-01

Aim The aim of the present study was to identify the various background variables and its influence on behavior management problems (BMP) in children. Materials and methods The study included 165 children aged 2 to 8 years. During the initial dental visit, an experienced operator obtained each child’s background variables from accompanying guardians using a standardized questionnaire. Children’s dental behavior was rated by Frankel behavior rating scale. The behavior was then analyzed in relation to the answers of the questionnaire, and a logistic regression model was used to determine the power of the variables, separately or combined, to predict BMP. Results The logistic regression analysis considering differences in background variables between children with negative or positive behavior. Four variables turned out to be as predictors: Age, the guardian’s expectation of the child’s behavior at the dental examination, the child’s anxiety when meeting unfamiliar people, and the presence and absence of toothache. Conclusion The present study concluded that by means of simple questionnaire BMP in children may be expected if one of these attributes is found. Clinical significance Information on the origin of dental fear and uncooperative behavior in a child patient prior to treatment process may help the pediatric dentist plan appropriate behavior management and treatment strategy. How to cite this article Sharma A, Kumar D, Anand A, Mittal V, Singh A, Aggarwal N. Factors predicting Behavior Management Problems during Initial Dental Examination in Children Aged 2 to 8 Years. Int J Clin Pediatr Dent 2017;10(1):5-9. PMID:28377646

Empowerment variables for rehabilitation clients on perceived beliefs concerning work quality of life domains.

PubMed

Tschopp, Molly K; Frain, Michael P; Bishop, Malachy

2009-01-01

This article describes and presents an initial analysis of variables generally associated with empowerment towards perceived beliefs concerning quality of life work domains for individuals with disabilities. The model examines the domains of importance, satisfaction, control and degree of interference of disability that an individual feels towards work. The internet based study used results from 70 individuals with disabilities in varying aspects of work. The variables composing empowerment that correlated strongly with the work domains include: self-advocacy, self-efficacy, perceived stigma, and family resiliency as measured through coping. Quality of Life concerning work was measured through the DSC-C a domain specific QOL instrument.

Concurrently adjusting interrelated control parameters to achieve optimal engine performance

DOEpatents

Jiang, Li; Lee, Donghoon; Yilmaz, Hakan; Stefanopoulou, Anna

2015-12-01

Methods and systems for real-time engine control optimization are provided. A value of an engine performance variable is determined, a value of a first operating condition and a value of a second operating condition of a vehicle engine are detected, and initial values for a first engine control parameter and a second engine control parameter are determined based on the detected first operating condition and the detected second operating condition. The initial values for the first engine control parameter and the second engine control parameter are adjusted based on the determined value of the engine performance variable to cause the engine performance variable to approach a target engine performance variable. In order to cause the engine performance variable to approach the target engine performance variable, adjusting the initial value for the first engine control parameter necessitates a corresponding adjustment of the initial value for the second engine control parameter.

Setting the scene for SWOT: global maps of river reach hydrodynamic variables

NASA Astrophysics Data System (ADS)

Schumann, Guy J.-P.; Durand, Michael; Pavelsky, Tamlin; Lion, Christine; Allen, George

2017-04-01

Credible and reliable characterization of discharge from the Surface Water and Ocean Topography (SWOT) mission using the Manning-based algorithms needs a prior estimate constraining reach-scale channel roughness, base flow and river bathymetry. For some places, any one of those variables may exist locally or even regionally as a measurement, which is often only at a station, or sometimes as a basin-wide model estimate. However, to date none of those exist at the scale required for SWOT and thus need to be mapped at a continental scale. The prior estimates will be employed for producing initial discharge estimates, which will be used as starting-guesses for the various Manning-based algorithms, to be refined using the SWOT measurements themselves. A multitude of reach-scale variables were derived, including Landsat-based width, SRTM slope and accumulation area. As a possible starting point for building the prior database of low flow, river bathymetry and channel roughness estimates, we employed a variety of sources, including data from all GRDC records, simulations from the long-time runs of the global water balance model (WBM), and reach-based calculations from hydraulic geometry relationships as well as Manning's equation. Here, we present the first global maps of this prior database with some initial validation, caveats and prospective uses.

Career Decision Status as a Predictor of Resignation Behavior Five Years Later

ERIC Educational Resources Information Center

Earl, Joanne K.; Minbashian, Amirali; Sukijjakhamin, Aun; Bright, Jim E. H.

2011-01-01

This paper extends earlier research exploring the relationship between career decision status and work outcomes by examining resignation behavior in a group of new graduates five years after initial appointment. On appointment various measures were collected including career decision status variables. Earlier research identified a significant…

An analysis of rotor blade twist variables associated with different Euler sequences and pretwist treatments

NASA Technical Reports Server (NTRS)

Alkire, K.

1984-01-01

A nonlinear analysis which is necessary to adequately model elastic helicopter rotor blades experiencing moderately large deformations was examined. The analysis must be based on an appropriate description of the blade's deformation geometry including elastic bending and twist. Built-in pretwist angles complicate the deformation process ant its definition. Relationships between the twist variables associated with different rotation sequences and corresponding forms of the transformation matrix are lasted. Relationships between the twist variables associated with first, the pretwist combined with the deformation twist are included. Many of the corresponding forms of the transformation matrix for the two cases are listed. It is shown that twist variables connected with the combined twist treatment are related to those where the pretwist is applied initially. A method to determine the relationships and some results are outlined. A procedure to evaluate the transformation matrix that eliminates the Eulerlike sequence altogether is demonstrated. The resulting form of the transformation matrix is unaffected by rotation sequence or pretwist treatment.

Variability and Comprehensiveness of North American Online Available Physical Therapy Protocols Following Hip Arthroscopy for Femoroacetabular Impingement and Labral Repair.

PubMed

Cvetanovich, Gregory L; Lizzio, Vincent; Meta, Fabien; Chan, Derek; Zaltz, Ira; Nho, Shane J; Makhni, Eric C

2017-11-01

To assess comprehensiveness and variability of postoperative physical therapy protocols published online following hip arthroscopy for femoroacetabular impingement (FAI) and/or labral repair. Surgeons were identified by the International Society for Hip Arthroscopy "Find a Surgeon" feature in North America (http://www.isha.net/members/, search August 10, 2016). Exclusion criteria included nonsurgeons and protocols for conditions other than hip arthroscopy for FAI and/or labral tear. Protocols were identified by review of surgeons' personal and departmental websites and evaluated for postoperative restrictions, rehabilitation components, and the time points for ending restrictions and initiating activities. Of 111 surgeons available online, 31 (27.9%) had postoperative hip arthroscopy physical therapy protocols available online. Bracing was used in 54.8% (17/31) of protocols for median 2-week duration (range, 1-6 weeks). Most protocols specified the initial postoperative weight-bearing status (29/31, 93.5%), most frequently partial weight-bearing with 20 pounds foot flat (20/29, 69.0%). The duration of weight-bearing restriction was median 3 weeks (range, 2-6) for FAI and median 6 weeks (range, 3-8) for microfracture. The majority of protocols specified initial range of motion limitations (26/31, 83.9%) for median 3 weeks (range, 1.5-12). There was substantial variation in the rehabilitation activities and time points for initiating activities. Time to return to running was specified by 20/31 (64.5%) protocols at median 12 weeks (range, 6-19), and return to sport timing was specified by 13/31 (41.9%) protocols at median 15.5 weeks (range, 9-23). There is considerable variability in postoperative physical therapy protocols available online following hip arthroscopy for FAI, including postoperative restrictions, rehabilitation activities, and time points for activities. This information offers residents, fellows, and established hip arthroscopists a centralized comparison of publicly available physical therapy protocols following hip arthroscopy. Practicing arthroscopists might find this analysis useful to compare various therapy strategies to their own recommendations. The variability we report can also provide inspiration for future efficacy research toward a more standard rehabilitation. Copyright © 2017. Published by Elsevier Inc.

Modeling hydrologic and geomorphic hazards across post-fire landscapes using a self-organizing map approach

USGS Publications Warehouse

Friedel, Michael J.

2011-01-01

Few studies attempt to model the range of possible post-fire hydrologic and geomorphic hazards because of the sparseness of data and the coupled, nonlinear, spatial, and temporal relationships among landscape variables. In this study, a type of unsupervised artificial neural network, called a self-organized map (SOM), is trained using data from 540 burned basins in the western United States. The sparsely populated data set includes variables from independent numerical landscape categories (climate, land surface form, geologic texture, and post-fire condition), independent landscape classes (bedrock geology and state), and dependent initiation processes (runoff, landslide, and runoff and landslide combination) and responses (debris flows, floods, and no events). Pattern analysis of the SOM-based component planes is used to identify and interpret relations among the variables. Application of the Davies-Bouldin criteria following k-means clustering of the SOM neurons identified eight conceptual regional models for focusing future research and empirical model development. A split-sample validation on 60 independent basins (not included in the training) indicates that simultaneous predictions of initiation process and response types are at least 78% accurate. As climate shifts from wet to dry conditions, forecasts across the burned landscape reveal a decreasing trend in the total number of debris flow, flood, and runoff events with considerable variability among individual basins. These findings suggest the SOM may be useful in forecasting real-time post-fire hazards, and long-term post-recovery processes and effects of climate change scenarios.

Do Cognitive Models Help in Predicting the Severity of Posttraumatic Stress Disorder, Phobia, and Depression After Motor Vehicle Accidents? A Prospective Longitudinal Study

PubMed Central

Ehring, Thomas; Ehlers, Anke; Glucksman, Edward

2008-01-01

The study investigated the power of theoretically derived cognitive variables to predict posttraumatic stress disorder (PTSD), travel phobia, and depression following injury in a motor vehicle accident (MVA). MVA survivors (N = 147) were assessed at the emergency department on the day of their accident and 2 weeks, 1 month, 3 months, and 6 months later. Diagnoses were established with the Structured Clinical Interview for DSM–IV. Predictors included initial symptom severities; variables established as predictors of PTSD in E. J. Ozer, S. R. Best, T. L. Lipsey, and D. S. Weiss's (2003) meta-analysis; and variables derived from cognitive models of PTSD, phobia, and depression. Results of nonparametric multiple regression analyses showed that the cognitive variables predicted subsequent PTSD and depression severities over and above what could be predicted from initial symptom levels. They also showed greater predictive power than the established predictors, although the latter showed similar effect sizes as in the meta-analysis. In addition, the predictors derived from cognitive models of PTSD and depression were disorder-specific. The results support the role of cognitive factors in the maintenance of emotional disorders following trauma. PMID:18377119

Evaluating science return in space exploration initiative architectures

NASA Technical Reports Server (NTRS)

Budden, Nancy Ann; Spudis, Paul D.

1993-01-01

Science is an important aspect of the Space Exploration Initiative, a program to explore the Moon and Mars with people and machines. Different SEI mission architectures are evaluated on the basis of three variables: access (to the planet's surface), capability (including number of crew, equipment, and supporting infrastructure), and time (being the total number of man-hours available for scientific activities). This technique allows us to estimate the scientific return to be expected from different architectures and from different implementations of the same architecture. Our methodology allows us to maximize the scientific return from the initiative by illuminating the different emphases and returns that result from the alternative architectural decisions.

Salinity anomaly as a trigger for ENSO events

PubMed Central

Zhu, Jieshun; Huang, Bohua; Zhang, Rong-Hua; Hu, Zeng-Zhen; Kumar, Arun; Balmaseda, Magdalena A.; Marx, Lawrence; Kinter III, James L.

2014-01-01

According to the classical theories of ENSO, subsurface anomalies in ocean thermal structure are precursors for ENSO events and their initial specification is essential for skillful ENSO forecast. Although ocean salinity in the tropical Pacific (particularly in the western Pacific warm pool) can vary in response to El Niño events, its effect on ENSO evolution and forecasts of ENSO has been less explored. Here we present evidence that, in addition to the passive response, salinity variability may also play an active role in ENSO evolution, and thus important in forecasting El Niño events. By comparing two forecast experiments in which the interannually variability of salinity in the ocean initial states is either included or excluded, the salinity variability is shown to be essential to correctly forecast the 2007/08 La Niña starting from April 2007. With realistic salinity initial states, the tendency to decay of the subsurface cold condition during the spring and early summer 2007 was interrupted by positive salinity anomalies in the upper central Pacific, which working together with the Bjerknes positive feedback, contributed to the development of the La Niña event. Our study suggests that ENSO forecasts will benefit from more accurate salinity observations with large-scale spatial coverage. PMID:25352285

Salinity anomaly as a trigger for ENSO events.

PubMed

Zhu, Jieshun; Huang, Bohua; Zhang, Rong-Hua; Hu, Zeng-Zhen; Kumar, Arun; Balmaseda, Magdalena A; Marx, Lawrence; Kinter, James L

2014-10-29

According to the classical theories of ENSO, subsurface anomalies in ocean thermal structure are precursors for ENSO events and their initial specification is essential for skillful ENSO forecast. Although ocean salinity in the tropical Pacific (particularly in the western Pacific warm pool) can vary in response to El Niño events, its effect on ENSO evolution and forecasts of ENSO has been less explored. Here we present evidence that, in addition to the passive response, salinity variability may also play an active role in ENSO evolution, and thus important in forecasting El Niño events. By comparing two forecast experiments in which the interannually variability of salinity in the ocean initial states is either included or excluded, the salinity variability is shown to be essential to correctly forecast the 2007/08 La Niña starting from April 2007. With realistic salinity initial states, the tendency to decay of the subsurface cold condition during the spring and early summer 2007 was interrupted by positive salinity anomalies in the upper central Pacific, which working together with the Bjerknes positive feedback, contributed to the development of the La Niña event. Our study suggests that ENSO forecasts will benefit from more accurate salinity observations with large-scale spatial coverage.

Childhood maltreatment and early alcohol use among high-risk adolescents.

PubMed

Hamburger, Merle E; Leeb, Rebecca T; Swahn, Monica H

2008-03-01

Child maltreatment (CM) is prevalent among U.S. youth and has been associated with subsequent maladaptive behaviors, including substance use. The current study examines the associations between early child maltreatment and (1) preteen alcohol-use initiation and (2) heavy episodic drinking among students in a large study of adolescents. The Youth Violence Survey is a cross-sectional survey of public school students enrolled in Grades 7,9, 11, and 12 in a school district in a high-risk community. The analysis sample was limited to students who provided complete data on all relevant variables (N= 3,559). Fifty-two percent of the analysis sample was female. Early child maltreatment was defined as witnessing domestic violence and experiencing physical and/or sexual abuse before the age of 10 years. Outcome variables include ever drinking alcohol, preteen alcohol-use initiation, and heavy episodic drinking. Witnessing domestic violence, experiencing physical abuse, and experiencing sexual abuse were significantly associated with preteen alcohol-use initiation (adjusted odds ratio [AOR] = 1.55, 95% confidence interval [CI]: 1.26-1.91; AOR = 2.10, 95% CI: 1.69-2.63; AOR = 1.57, 95% CI: 1.16-2.14, respectively). Students who experienced one or more types of maltreatment were 1.5-3 times more likely to report preteen alcohol-use initiation. Heavy episodic drinking was associated only with childhood sexual abuse in boys (AOR = 2.62, 95% CI: 1.52-4.50). Prevention and treatment of the negative impact of early child maltreatment may delay and reduce alcohol use.

Should Age at Diagnosis Be Included as an Additional Variable in the Risk of Recurrence Classification System in Patients with Differentiated Thyroid Cancer.

PubMed

Pitoia, Fabián; Jerkovich, Fernando; Smulever, Anabella; Brenta, Gabriela; Bueno, Fernanda; Cross, Graciela

2017-07-01

To evaluate the influence of age at diagnosis on the frequency of structural incomplete response (SIR) according to the modified risk of recurrence (RR) staging system from the American Thyroid Association guidelines. We performed a retrospective analysis of 268 patients with differentiated thyroid cancer (DTC) followed up for at least 3 years after initial treatment (total thyroidectomy and remnant ablation). The median follow-up in the whole cohort was 74.3 months (range: 36.1-317.9) and the median age at diagnosis was 45.9 years (range: 18-87). The association between age at diagnosis and the initial and final response to treatment was assessed with analysis of variance (ANOVA). Patients were also divided into several groups considering age younger and older than 40, 50, and 60 years. Age at diagnosis was not associated with either an initial or final statistically significant different SIR to treatment ( p = 0.14 and p = 0.58, respectively). Additionally, we did not find any statistically significant differences when the percentages of SIR considering the classification of RR were compared between different groups of patients by using several age cutoffs. When patients are correctly risk stratified, it seems that age at diagnosis is not involved in the frequency of having a SIR at the initial evaluation or at the final follow-up, so it should not be included as an additional variable to be considered in the RR classifications.

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

Stevens, D.L.; Simonen, F.A.; Strosnider, J. Jr.

The VISA (Vessel Integrity Simulation Analysis) code was developed as part of the NRC staff evaluation of pressurized thermal shock. VISA uses Monte Carlo simulation to evaluate the failure probability of a pressurized water reactor (PWR) pressure vessel subjected to a pressure and thermal transient specified by the user. Linear elastic fracture mechanics are used to model crack initiation and propagation. parameters for initial crack size, copper content, initial RT/sub NDT/, fluence, crack-initiation fracture toughness, and arrest fracture toughness are treated as random variables. This report documents the version of VISA used in the NRC staff report (Policy Issue frommore » J.W. Dircks to NRC Commissioners, Enclosure A: NRC Staff Evaluation of Pressurized Thermal Shock, November 1982, SECY-82-465) and includes a user's guide for the code.« less

A satellite observation test bed for cloud parameterization development

NASA Astrophysics Data System (ADS)

Lebsock, M. D.; Suselj, K.

2015-12-01

We present an observational test-bed of cloud and precipitation properties derived from CloudSat, CALIPSO, and the the A-Train. The focus of the test-bed is on marine boundary layer clouds including stratocumulus and cumulus and the transition between these cloud regimes. Test-bed properties include the cloud cover and three dimensional cloud fraction along with the cloud water path and precipitation water content, and associated radiative fluxes. We also include the subgrid scale distribution of cloud and precipitation, and radiaitive quantities, which must be diagnosed by a model parameterization. The test-bed further includes meterological variables from the Modern Era Retrospective-analysis for Research and Applications (MERRA). MERRA variables provide the initialization and forcing datasets to run a parameterization in Single Column Model (SCM) mode. We show comparisons of an Eddy-Diffusivity/Mass-FLux (EDMF) parameterization coupled to micorphsycis and macrophysics packages run in SCM mode with observed clouds. Comparsions are performed regionally in areas of climatological subsidence as well stratified by dynamical and thermodynamical variables. Comparisons demonstrate the ability of the EDMF model to capture the observed transitions between subtropical stratocumulus and cumulus cloud regimes.

[Predicting the outcome in severe injuries: an analysis of 2069 patients from the trauma register of the German Society of Traumatology (DGU)].

PubMed

Rixen, D; Raum, M; Bouillon, B; Schlosser, L E; Neugebauer, E

2001-03-01

On hospital admission numerous variables are documented from multiple trauma patients. The value of these variables to predict outcome are discussed controversially. The aim was the ability to initially determine the probability of death of multiple trauma patients. Thus, a multivariate probability model was developed based on data obtained from the trauma registry of the Deutsche Gesellschaft für Unfallchirurgie (DGU). On hospital admission the DGU trauma registry collects more than 30 variables prospectively. In the first step of analysis those variables were selected, that were assumed to be clinical predictors for outcome from literature. In a second step a univariate analysis of these variables was performed. For all primary variables with univariate significance in outcome prediction a multivariate logistic regression was performed in the third step and a multivariate prognostic model was developed. 2069 patients from 20 hospitals were prospectively included in the trauma registry from 01.01.1993-31.12.1997 (age 39 +/- 19 years; 70.0% males; ISS 22 +/- 13; 18.6% lethality). From more than 30 initially documented variables, the age, the GCS, the ISS, the base excess (BE) and the prothrombin time were the most important prognostic factors to predict the probability of death (P(death)). The following prognostic model was developed: P(death) = 1/1 + e(-[k + beta 1(age) + beta 2(GCS) + beta 3(ISS) + beta 4(BE) + beta 5(prothrombin time)]) where: k = -0.1551, beta 1 = 0.0438 with p < 0.0001, beta 2 = -0.2067 with p < 0.0001, beta 3 = 0.0252 with p = 0.0071, beta 4 = -0.0840 with p < 0.0001 and beta 5 = -0.0359 with p < 0.0001. Each of the five variables contributed significantly to the multifactorial model. These data show that the age, GCS, ISS, base excess and prothrombin time are potentially important predictors to initially identify multiple trauma patients with a high risk of lethality. With the base excess and prothrombin time value, as only variables of this multifactorial model that can be therapeutically influenced, it might be possible to better guide early and aggressive therapy.

Variability of Anticipatory Postural Adjustments During Gait Initiation in Individuals With Parkinson Disease.

PubMed

Lin, Cheng-Chieh; Creath, Robert A; Rogers, Mark W

2016-01-01

In people with Parkinson disease (PD), difficulties with initiating stepping may be related to impairments of anticipatory postural adjustments (APAs). Increased variability in step length and step time has been observed in gait initiation in individuals with PD. In this study, we investigated whether the ability to generate consistent APAs during gait initiation is compromised in these individuals. Fifteen subjects with PD and 8 healthy control subjects were instructed to take rapid forward steps after a verbal cue. The changes in vertical force and ankle marker position were recorded via force platforms and a 3-dimensional motion capture system, respectively. Means, standard deviations, and coefficients of variation of both timing and magnitude of vertical force, as well as stepping variables, were calculated. During the postural phase of gait initiation the interval was longer and the force modulation was smaller in subjects with PD. Both the variability of timing and force modulation were larger in subjects with PD. Individuals with PD also had a longer time to complete the first step, but no significant differences were found for the variability of step time, length, and speed between groups. The increased variability of APAs during gait initiation in subjects with PD could affect posture-locomotion coupling, and lead to start hesitation, and even falls. Future studies are needed to investigate the effect of rehabilitation interventions on the variability of APAs during gait initiation in individuals with PD.Video abstract available for more insights from the authors (see Supplemental Digital Content 1, http://links.lww.com/JNPT/A119).

Refrigerator with variable capacity compressor and cycle priming action through capacity control and associated methods

DOEpatents

Gomes, Alberto Regio; Litch, Andrew D.; Wu, Guolian

2016-03-15

A refrigerator appliance (and associated method) that includes a condenser, evaporator and a multi-capacity compressor. The appliance also includes a pressure reducing device arranged within an evaporator-condenser refrigerant circuit, and a valve system for directing or restricting refrigerant flow through the device. The appliance further includes a controller for operating the compressor upon the initiation of a compressor ON-cycle at a priming capacity above a nominal capacity for a predetermined or calculated duration.

Approximate techniques of structural reanalysis

NASA Technical Reports Server (NTRS)

Noor, A. K.; Lowder, H. E.

1974-01-01

A study is made of two approximate techniques for structural reanalysis. These include Taylor series expansions for response variables in terms of design variables and the reduced-basis method. In addition, modifications to these techniques are proposed to overcome some of their major drawbacks. The modifications include a rational approach to the selection of the reduced-basis vectors and the use of Taylor series approximation in an iterative process. For the reduced basis a normalized set of vectors is chosen which consists of the original analyzed design and the first-order sensitivity analysis vectors. The use of the Taylor series approximation as a first (initial) estimate in an iterative process, can lead to significant improvements in accuracy, even with one iteration cycle. Therefore, the range of applicability of the reanalysis technique can be extended. Numerical examples are presented which demonstrate the gain in accuracy obtained by using the proposed modification techniques, for a wide range of variations in the design variables.

Heart rate variability measured early in patients with evolving acute coronary syndrome and 1-year outcomes of rehospitalization and mortality.

PubMed

Harris, Patricia R E; Stein, Phyllis K; Fung, Gordon L; Drew, Barbara J

2014-01-01

This study sought to examine the prognostic value of heart rate variability (HRV) measurement initiated immediately after emergency department presentation for patients with acute coronary syndrome (ACS). Altered HRV has been associated with adverse outcomes in heart disease, but the value of HRV measured during the earliest phases of ACS related to risk of 1-year rehospitalization and death has not been established. Twenty-four-hour Holter recordings of 279 patients with ACS were initiated within 45 minutes of emergency department arrival; recordings with ≥18 hours of sinus rhythm were selected for HRV analysis (number [N] =193). Time domain, frequency domain, and nonlinear HRV were examined. Survival analysis was performed. During the 1-year follow-up, 94 patients were event-free, 82 were readmitted, and 17 died. HRV was altered in relation to outcomes. Predictors of rehospitalization included increased normalized high frequency power, decreased normalized low frequency power, and decreased low/high frequency ratio. Normalized high frequency >42 ms(2) predicted rehospitalization while controlling for clinical variables (hazard ratio [HR] =2.3; 95% confidence interval [CI] =1.4-3.8, P=0.001). Variables significantly associated with death included natural logs of total power and ultra low frequency power. A model with ultra low frequency power <8 ms(2) (HR =3.8; 95% CI =1.5-10.1; P=0.007) and troponin >0.3 ng/mL (HR =4.0; 95% CI =1.3-12.1; P=0.016) revealed that each contributed independently in predicting mortality. Nonlinear HRV variables were significant predictors of both outcomes. HRV measured close to the ACS onset may assist in risk stratification. HRV cut-points may provide additional, incremental prognostic information to established assessment guidelines, and may be worthy of additional study.

Choice between Single and Multiple Reinforcers in Concurrent-Chains Schedules

ERIC Educational Resources Information Center

Mazur, James E.

2006-01-01

Pigeons responded on concurrent-chains schedules with equal variable-interval schedules as initial links. One terminal link delivered a single reinforcer after a fixed delay, and the other terminal link delivered either three or five reinforcers, each preceded by a fixed delay. Some conditions included a postreinforcer delay after the single…

Relationships between Observations of Elementary Mathematics Instruction and Student Achievement: Exploring Variability across Districts

ERIC Educational Resources Information Center

Lynch, Kathleen; Chin, Mark; Blazar, David

2017-01-01

Much debate surrounding teacher quality has focused on students' standardized test scores, but recent federal and state initiatives have emphasized the use of multiple measures to evaluate teacher quality, including classroom observations. In this study, we explore differences across school districts in the relationship between student achievement…

Modeling heart rate variability including the effect of sleep stages

NASA Astrophysics Data System (ADS)

Soliński, Mateusz; Gierałtowski, Jan; Żebrowski, Jan

2016-02-01

We propose a model for heart rate variability (HRV) of a healthy individual during sleep with the assumption that the heart rate variability is predominantly a random process. Autonomic nervous system activity has different properties during different sleep stages, and this affects many physiological systems including the cardiovascular system. Different properties of HRV can be observed during each particular sleep stage. We believe that taking into account the sleep architecture is crucial for modeling the human nighttime HRV. The stochastic model of HRV introduced by Kantelhardt et al. was used as the initial starting point. We studied the statistical properties of sleep in healthy adults, analyzing 30 polysomnographic recordings, which provided realistic information about sleep architecture. Next, we generated synthetic hypnograms and included them in the modeling of nighttime RR interval series. The results of standard HRV linear analysis and of nonlinear analysis (Shannon entropy, Poincaré plots, and multiscale multifractal analysis) show that—in comparison with real data—the HRV signals obtained from our model have very similar properties, in particular including the multifractal characteristics at different time scales. The model described in this paper is discussed in the context of normal sleep. However, its construction is such that it should allow to model heart rate variability in sleep disorders. This possibility is briefly discussed.

Prospective Analysis of the Influence of Sport and Educational Factors on the Prevalence and Initiation of Smoking in Older Adolescents from Croatia.

PubMed

Zenic, Natasa; Ban, Djivo; Jurisic, Sanja; Cubela, Mladen; Rodek, Jelena; Ostojic, Ljerka; Jelicic, Mario; Bianco, Antonino; Sekulic, Damir

2017-04-20

The prevalence of smoking among Croatian adolescents is alarmingly high, but no previous study has prospectively examined the sport- and academic-factors associated with smoking and smoking initiation. This study aimed to prospectively examine the associations between scholastic (educational) achievement and sport factors and smoking in 16- to 18-year-old adolescents. This two-year prospective cohort study included 644 adolescents who were 16 years of age at baseline (46% females). Baseline testing was implemented at the beginning of the 3rd year of high school (September 2014) when participants were 16 years old. Follow-up testing was completed at the end of the fourth year of high school, which occurred 20 months later. The evaluated predictor variables were educational-achievement- and sport-related-factors. The outcome variables were (i) smoking at baseline; (ii) smoking at follow-up; and (iii) smoking initiation over the course of the study. We assessed the associations between predictors and outcomes using logistic regression models adjusted for age, gender, socioeconomic status, and conflict with parents. The educational variables were consistently associated with smoking, with lower grade-point-average (Baseline: odd ratio (OR): 2.01, 95% confidence interval (CI): 1.61-2.55; Follow-up: 1.59, 1.31-1.94), more frequent absence from school (Baseline: OR: 1.40, 95% CI: 1.19-1.69; Follow-up: 1.30, 1.08-1.58), and lower behavioral grades (Baseline: OR: 1.80, 95% CI: 1.10-2.89; Follow-up: 1.57, 1.03-2.41) in children who smoke. Adolescents who reported quitting sports were at greater odds of being smokers (Baseline: 2.07, 1.31-3.32; Follow-up: 1.66, 1.09-2.56). Sport competitive achievement at baseline was protective against smoking initiation during following two-year period (0.45, 0.21-0.91). While the influence of the educational variables on smoking initiation has been found to be established earlier; sport achievement was identified as a significant protective factor against initiating smoking in older adolescents. Results should be used in development of an anti-smoking preventive campaign in older adolescents.

Variables Affecting Pharmacy Students’ Patient Care Interventions during Advanced Pharmacy Practice Experiences

PubMed Central

Patterson, Brandon J.; Sen, Sanchita; Bingham, Angela L.; Bowen, Jane F.; Ereshefsky, Benjamin; Siemianowski, Laura A.

2016-01-01

Objective. To identify the temporal effect and factors associated with student pharmacist self-initiation of interventions during acute patient care advanced pharmacy practice experiences (APPE). Methods. During the APPE, student pharmacists at an academic medical center recorded their therapeutic interventions and who initiated the intervention throughout clinical rotations. At the end of the APPE student pharmacists completed a demographic survey. Results. Sixty-two student pharmacists were included. Factors associated with lower rates of self-initiated interventions were infectious diseases and pediatrics APPEs and an intention to pursue a postgraduate residency. Timing of the APPE, previous specialty elective course completion, and previous hospital experience did not result in any significant difference in self-initiated recommendations. Conclusion. Preceptors should not base practice experience expectations for self-initiated interventions on previous student experience or future intentions. Additionally, factors leading to lower rates of self-initiated interventions on infectious diseases or pediatrics APPEs should be explored. PMID:27756924

Factors associated with the initiation of disease-modifying antirheumatic drugs in newly diagnosed rheumatoid arthritis: a retrospective claims database study.

PubMed

Bonafede, Machaon M K; Fox, Kathleen M; Johnson, Barbara H; Watson, Crystal; Gandra, Shravanthi R

2012-02-01

The objectives of this study were to quantify the proportion of US patients with newly diagnosed rheumatoid arthritis (RA) in whom disease-modifying antirheumatic drug (DMARD) therapy was initiated within 12 months following diagnosis, to determine mean time to initiation, to compare the characteristics of initiators versus noninitiators, and to identify factors associated with noninitiation. A retrospective study was conducted using claims from the databases of commercial managed care and Medicare supplemental managed care to identify patients with claims containing codes for RA dated January 1, 2004, through September 30, 2008. The percentage of patients with RA and a prescription for a DMARD within 12 months after the index date (initiators) was evaluated. The characteristics of DMARD initiators and noninitiators during the preindex period were compared, including demographic and clinical characteristics, health care resource utilization, and cost variables. The probability of DMARD initiation was determined using survival analysis. Multivariate analysis was performed to estimate mean time from diagnosis to DMARD initiation based on demographic and clinical variables. Of 26,911 patients with newly diagnosed RA identified in the database searches, 63% had been prescribed a DMARD within 12 months after diagnosis. DMARD initiators were significantly more likely to have had a rheumatologist visit and rheumatoid factor testing and were more likely to have received a corticosteroid and/or an NSAID (all, P < 0.001). DMARD initiators had significantly lower total costs ($10,534 vs $12,725, respectively) and pharmacy drug costs ($2438 vs $2822) over the preindex period compared with noninitiators (both, P < 0.001). Independent factors associated with a greater likelihood of DMARD initiation included a rheumatologist visit, rheumatoid factor testing, NSAID use, and corticosteroid use. Age ≥85 years and the presence of comorbidities were associated with a significantly lower likelihood of DMARD initiation. Among managed care enrollees in the present analysis, 37% of patients newly diagnosed with RA were not being treated with DMARDs in the first 12 months after diagnosis. Time to DMARD initiation plateaued after 90 days, suggesting that if a patient was not prescribed a DMARD soon after RA diagnosis, he or she was not likely to receive one. Copyright © 2012 Elsevier HS Journals, Inc. All rights reserved.

Evolutionary cost analysis of valsartan initiation among patients with hypertension: a time series approach.

PubMed

Sun, Peter; Chang, Joanne; Zhang, Jie; Kahler, Kristijan H

2012-01-01

This study examines the evolutionary impact of valsartan initiation on medical costs. A retrospective time series study design was used with a large, US national commercial claims database for the period of 2004-2008. Hypertensive patients who initiated valsartan between the ages of 18 and 63, and had continuous enrollment for 24-month pre-initiation period and 24-month post-initiation period were selected. Patients' monthly medical costs were calculated based on individual claims. A novel time series model was devised with monthly medical costs as its dependent variables, autoregressive integrated moving average (ARIMA) as its stochastic components, and four indicative variables as its decomposed interventional components. The number of post-initiation months before a cost-offset point was also assessed. Patients (n = 18,269) had mean age of 53 at the initiation date, and 53% of them were female. The most common co-morbid conditions were dyslipidemia (52%), diabetes (24%), and hypertensive complications (17%). The time series model suggests that medical costs were increasing by approximately $10 per month (p < 0.01) before the initiation, and decreasing by approximately $6 per month (p < 0.01) after the initiation. After the 4th post-initiation month, medical costs for patients with the initiation were statistically significantly lower (p < 0.01) than forecasted medical costs for the same patients without the initiation. The study has its limitations in data representativeness, ability to collect unrecorded clinical conditions, treatments, and costs, as well as its generalizability to patients with different characteristics. Commercially insured hypertensive patients experienced monthly medical cost increase before valsartan initiation. Based on our model, the evolutionary impact of the initiation on medical costs included a temporary cost surge, a gradual, consistent, and statistically significant cost decrease, and a cost-offset point around the 4th post-initiation month.

Cognitive function after the initiation of adjuvant endocrine therapy in early-stage breast cancer: an observational cohort study.

PubMed

Ganz, Patricia A; Petersen, Laura; Castellon, Steven A; Bower, Julienne E; Silverman, Daniel H S; Cole, Steven W; Irwin, Michael R; Belin, Thomas R

2014-11-01

This report examines cognitive complaints and neuropsychological (NP) testing outcomes in patients with early-stage breast cancer after the initiation of endocrine therapy (ET) to determine whether this therapy plays any role in post-treatment cognitive complaints. One hundred seventy-three participants from the Mind Body Study (MBS) observational cohort provided data from self-report questionnaires and NP testing obtained at enrollment (T1, before initiation of ET), and 6 months later (T2). Bivariate analyses compared demographic and treatment variables, cognitive complaints, depressive symptoms, quality of life, and NP functioning between those who received ET versus not. Multivariable linear regression models examined predictors of cognitive complaints at T2, including selected demographic variables, depressive symptoms, ET use, and other medical variables, along with NP domains that were identified in bivariate analyses. Seventy percent of the 173 MBS participants initiated ET, evenly distributed between tamoxifen or aromatase inhibitors. ET-treated participants reported significantly increased language and communication (LC) cognitive complaints at T2 (P = .003), but no significant differences in NP test performance. Multivariable regression on LC at T2 found higher LC complaints significantly associated with T1 LC score (P < .001), ET at T2 (P = .004), interaction between ET and past hormone therapy (HT) (P < .001), and diminished improvement in NP psychomotor function (P = .05). Depressive symptoms were not significant (P = .10). Higher LC complaints are significantly associated with ET 6 months after starting treatment and reflect diminished improvements in some NP tests. Past HT is a significant predictor of higher LC complaints after initiation of ET. © 2014 by American Society of Clinical Oncology.

Cognitive Function After the Initiation of Adjuvant Endocrine Therapy in Early-Stage Breast Cancer: An Observational Cohort Study

PubMed Central

Ganz, Patricia A.; Petersen, Laura; Castellon, Steven A.; Bower, Julienne E.; Silverman, Daniel H.S.; Cole, Steven W.; Irwin, Michael R.; Belin, Thomas R.

2014-01-01

Purpose This report examines cognitive complaints and neuropsychological (NP) testing outcomes in patients with early-stage breast cancer after the initiation of endocrine therapy (ET) to determine whether this therapy plays any role in post-treatment cognitive complaints. Patients and Methods One hundred seventy-three participants from the Mind Body Study (MBS) observational cohort provided data from self-report questionnaires and NP testing obtained at enrollment (T1, before initiation of ET), and 6 months later (T2). Bivariate analyses compared demographic and treatment variables, cognitive complaints, depressive symptoms, quality of life, and NP functioning between those who received ET versus not. Multivariable linear regression models examined predictors of cognitive complaints at T2, including selected demographic variables, depressive symptoms, ET use, and other medical variables, along with NP domains that were identified in bivariate analyses. Results Seventy percent of the 173 MBS participants initiated ET, evenly distributed between tamoxifen or aromatase inhibitors. ET-treated participants reported significantly increased language and communication (LC) cognitive complaints at T2 (P = .003), but no significant differences in NP test performance. Multivariable regression on LC at T2 found higher LC complaints significantly associated with T1 LC score (P < .001), ET at T2 (P = .004), interaction between ET and past hormone therapy (HT) (P < .001), and diminished improvement in NP psychomotor function (P = .05). Depressive symptoms were not significant (P = .10). Conclusion Higher LC complaints are significantly associated with ET 6 months after starting treatment and reflect diminished improvements in some NP tests. Past HT is a significant predictor of higher LC complaints after initiation of ET. PMID:25267747

GEO Carbon and GHG Initiative Task 3: Optimizing in-situ measurements of essential carbon cycle variables across observational networks

NASA Astrophysics Data System (ADS)

Durden, D.; Muraoka, H.; Scholes, R. J.; Kim, D. G.; Loescher, H. W.; Bombelli, A.

2017-12-01

The development of an integrated global carbon cycle observation system to monitor changes in the carbon cycle, and ultimately the climate system, across the globe is of crucial importance in the 21stcentury. This system should be comprised of space and ground-based observations, in concert with modelling and analysis, to produce more robust budgets of carbon and other greenhouse gases (GHGs). A global initiative, the GEO Carbon and GHG Initiative, is working within the framework of Group on Earth Observations (GEO) to promote interoperability and provide integration across different parts of the system, particularly at domain interfaces. Thus, optimizing the efforts of existing networks and initiatives to reduce uncertainties in budgets of carbon and other GHGs. This is a very ambitious undertaking; therefore, the initiative is separated into tasks to provide actionable objectives. Task 3 focuses on the optimization of in-situ observational networks. The main objective of Task 3 is to develop and implement a procedure for enhancing and refining the observation system for identified essential carbon cycle variables (ECVs) that meets user-defined specifications at minimum total cost. This work focuses on the outline of the implementation plan, which includes a review of essential carbon cycle variables and observation technologies, mapping the ECVs performance, and analyzing gaps and opportunities in order to design an improved observing system. A description of the gap analysis of in-situ observations that will begin in the terrestrial domain to address issues of missing coordination and large spatial gaps, then extend to ocean and atmospheric observations in the future, will be outlined as the subsequent step to landscape mapping of existing observational networks.

A pilot goal-directed perfusion initiative is associated with less acute kidney injury after cardiac surgery.

PubMed

Magruder, J Trent; Crawford, Todd C; Harness, Herbert Lynn; Grimm, Joshua C; Suarez-Pierre, Alejandro; Wierschke, Chad; Biewer, Jim; Hogue, Charles; Whitman, Glenn R; Shah, Ashish S; Barodka, Viachaslau

2017-01-01

We sought to determine whether a pilot goal-directed perfusion initiative could reduce the incidence of acute kidney injury after cardiac surgery. On the basis of the available literature, we identified goals to achieve during cardiopulmonary bypass (including maintenance of oxygen delivery >300 mL O2/min/m 2 and reduction in vasopressor use) that were combined into a goal-directed perfusion initiative and implemented as a quality improvement measure in patients undergoing cardiac surgery at Johns Hopkins during 2015. Goal-directed perfusion initiative patients were matched to controls who underwent cardiac surgery between 2010 and 2015 using propensity scoring across 15 variables. The primary and secondary outcomes were the incidence of acute kidney injury and the mean increase in serum creatinine within the first 72 hours after cardiac surgery. We used the goal-directed perfusion initiative in 88 patients and matched these to 88 control patients who were similar across all variables, including mean age (61 years in controls vs 64 years in goal-directed perfusion initiative patients, P = .12) and preoperative glomerular filtration rate (90 vs 83 mL/min, P = .34). Controls received more phenylephrine on cardiopulmonary bypass (mean 2.1 vs 1.4 mg, P < .001) and had lower nadir oxygen delivery (mean 241 vs 301 mL O2/min/m 2 , P < .001). Acute kidney injury incidence was 23.9% in controls and 9.1% in goal-directed perfusion initiative patients (P = .008); incidences of acute kidney injury stage 1, 2, and 3 were 19.3%, 3.4%, and 1.1% in controls, and 5.7%, 3.4%, and 0% in goal-directed perfusion initiative patients, respectively. Control patients exhibited a larger median percent increase in creatinine from baseline (27% vs 10%, P < .001). The goal-directed perfusion initiative was associated with reduced acute kidney injury incidence after cardiac surgery in this pilot study. Copyright © 2016. Published by Elsevier Inc.

Intraindividual variability of boldness is repeatable across contexts in a wild lizard.

PubMed

Highcock, Laura; Carter, Alecia J

2014-01-01

Animals do not behave in exactly the same way when repeatedly tested in the same context or situation, even once systematic variation, such as habituation, has been controlled for. This unpredictability is called intraindividual variability (IIV) and has been little studied in animals. Here we investigated how IIV in boldness (estimated by flight initiation distances) changed across two seasons--the dry, non-breeding season and the wet, breeding season--in a wild population of the Namibian rock agama, Agama planiceps. We found significant differences in IIV both between individuals and seasons, and IIV was higher in the wet season, suggesting plasticity in IIV. Further, IIV was highly repeatable (r = 0.61) between seasons and we found strong negative correlations between consistent individual differences in flight initiation distances, i.e. their boldness, and individuals' IIVs. We suggest that to understand personality in animals, researchers should generate a personality 'profile' that includes not only the relative level of a trait (i.e. its personality), but also its plasticity and variability under natural conditions.

Use of demographic and pharmacy data to identify patients included within both the Clinical Practice Research Datalink (CPRD) and The Health Improvement Network (THIN).

PubMed

Carbonari, Dena M; Saine, M Elle; Newcomb, Craig W; Blak, Betina; Roy, Jason A; Haynes, Kevin; Wood, Jennifer; Gallagher, Arlene M; Bhullar, Harshvinder; Cardillo, Serena; Hennessy, Sean; Strom, Brian L; Lo Re, Vincent

2015-09-01

Pharmacoepidemiology researchers often utilize data from two UK electronic medical record databases, the Clinical Practice Research Datalink (CPRD) and The Health Improvement Network (THIN), and may choose to combine the two in an effort to increase sample size. To minimize duplication of data, previous studies examined the practice-level overlap between these databases. However, the proportion of overlapping patients remains unknown. We developed a method using demographic and pharmacy variables to identify patients included in both CPRD and THIN, and applied this method to measure the proportion of overlapping patients who initiated the oral anti-diabetic drug saxagliptin. We conducted a cross-sectional study among patients initiating saxagliptin in CPRD and THIN between October 2009 and September 2012. Within both databases, we identified patients: (i) ≥18 years, (ii) newly prescribed saxagliptin, and (iii) with ≥180 days enrollment prior to saxagliptin initiation. Demographic data (birth year, sex, patient registration date, family number, and marital status) and prescriptions (including dates) for the first two oral anti-diabetic drugs prescribed within the study period were used to identify matching patients. Among 4202 CPRD and 3641 THIN patients initiating saxagliptin, 2574 overlapping patients (61% of CPRD saxagliptin initiators; 71% of THIN saxagliptin initiators) were identified. Among these patients, 2474 patients (96%) perfectly matched on all demographic and prescription data. Within each database, over 60% of patients initiating saxagliptin were included within both CPRD and THIN. Combined demographic and prescription data can be used to identify patients included in both CPRD and THIN. Copyright © 2015 John Wiley & Sons, Ltd.

Decadal evaluation of regional climate, air quality, and their interactions using WRF/Chem Version 3.6.1

NASA Astrophysics Data System (ADS)

Yahya, K.; Wang, K.; Campbell, P.; Glotfelty, T.; He, J.; Zhang, Y.

2015-08-01

The Weather Research and Forecasting model with Chemistry (WRF/Chem) v3.6.1 with the Carbon Bond 2005 (CB05) gas-phase mechanism is evaluated for its first decadal application during 2001-2010 using the Representative Concentration Pathway (RCP 8.5) emissions to assess its capability and appropriateness for long-term climatological simulations. The initial and boundary conditions are downscaled from the modified Community Earth System Model/Community Atmosphere Model (CESM/CAM5) v1.2.2. The meteorological initial and boundary conditions are bias-corrected using the National Center for Environmental Protection's Final (FNL) Operational Global Analysis data. Climatological evaluations are carried out for meteorological, chemical, and aerosol-cloud-radiation variables against data from surface networks and satellite retrievals. The model performs very well for the 2 m temperature (T2) for the 10 year period with only a small cold bias of -0.3 °C. Biases in other meteorological variables including relative humidity at 2 m, wind speed at 10 m, and precipitation tend to be site- and season-specific; however, with the exception of T2, consistent annual biases exist for most of the years from 2001 to 2010. Ozone mixing ratios are slightly overpredicted at both urban and rural locations but underpredicted at rural locations. PM2.5 concentrations are slightly overpredicted at rural sites, but slightly underpredicted at urban/suburban sites. In general, the model performs relatively well for chemical and meteorological variables, and not as well for aerosol-cloud-radiation variables. Cloud-aerosol variables including aerosol optical depth, cloud water path, cloud optical thickness, and cloud droplet number concentration are generally underpredicted on average across the continental US. Overpredictions of several cloud variables over eastern US result in underpredictions of radiation variables and overpredictions of shortwave and longwave cloud forcing which are important climate variables. While the current performance is deemed to be acceptable, improvements to the bias-correction method for CESM downscaling and the model parameterizations of cloud dynamics and thermodynamics, as well as aerosol-cloud interactions can potentially improve model performance for long-term climate simulations.

Variability in the initiation of resuscitation attempts by emergency medical services personnel during out-of-hospital cardiac arrest.

PubMed

Brooks, Steven C; Schmicker, Robert H; Cheskes, Sheldon; Christenson, Jim; Craig, Alan; Daya, Mohamud; Kudenchuk, Peter J; Nichol, Graham; Zive, Dana; Morrison, Laurie J

2017-08-01

Some patients with out-of-hospital cardiac arrest (OHCA) assessed by emergency medical services (EMS) do not receive attempts at resuscitation on the basis of perceived futility. 1) To measure variability in the initiation of resuscitation attempts in EMS-assessed OHCA patients across EMS agencies, 2) to evaluate the association between selected EMS agency characteristics and the proportion of patients receiving resuscitation attempts, and 3) to evaluate the association between proportion receiving resuscitation attempts and survival. A retrospective cohort study using data from 129 EMS agencies participating in the Resuscitation Outcomes Consortium (ROC) epidemiologic registry (EPISTRY) - Cardiac Arrest from 12/01/2005 to 12/31/2010. We included non-traumatic OHCA patients assessed by EMS. We included 86,912 OHCA patients. Overall, 54.8% had resuscitation attempted by EMS providers, varying from 23.9% to 100% (p=<0.001) across EMS agencies. The proportion of patients receiving a resuscitation attempt was 7.87% less (95% CI 3.73-12.0) among agencies with longer average response intervals (≥6min) compared with shorter average response intervals (<6min) and 16.9% less (95% CI 11.9-21.9) among agencies with higher levels of advanced life support (ALS) availability (≥50% of available units) compared with lower levels of ALS availability (<50% of available units). There was a moderate positive correlation between the proportion of patients with resuscitation attempts and survival to hospital discharge (r=0.54, p<0.001). The proportion of patients with OHCA who receive resuscitation attempts is variable across EMS agencies and is associated with EMS response interval, ALS unit availability and geographic region. On average, survival was higher among EMS agencies more likely to initiate resuscitation. Copyright © 2017 Elsevier B.V. All rights reserved.

Production of sugarcane and tropical grasses as a renewable energy source. Second annual report, 1978-1979

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

Not Available

1979-01-01

Reseach continued on tropical grasses from Saccharum and related genera as sources of intensively-produced, solar-dried biomass. Categories of candidate grasses include short-, intermediate-, and long-rotation species. These categories are based on the time interval required for maximum dry matter production, and on future management requirements of energy crops for intensive co-production with food crop commodities. Year 1 studies at the greenhouse and field-plot levels were continued and broadened during Year 2. This included candidate screening, importation and quarantine of new clones, breeding, controlled nitrogen and water regimes, chemical growth control, tissue expansion and maturation control, seeding rates, harvest frequency, andmore » variable row spacing. Second-year studies were extended to the project's field-scale and mechanized-harvest phases. These include initial economic anayses for the short-rotation phases. These include initial economic analyses for the short-rotation category of candidate species.« less

Enhancement of utilization of encryption engine

DOEpatents

Robertson, Robert J.; Witzke, Edward L.

2008-04-22

A method of enhancing throughput of a pipelined encryption/decryption engine for an encryption/decryption process has a predetermined number of stages and provides feedback around the stages (and of such an encryption/decryption engine) by receiving a source datablock for a given stage and encryption/decryption context identifier; indexing according to the encryption/decryption context identifier into a bank of initial variables to retrieve an initial variable for the source datablock; and generating an output datablock from the source datablock and its corresponding initial variable.

Initial characterization of unidentified Armillaria isolate from Serbia using LSU-IGS1 and TEF-1a genes

Treesearch

N. Keca; N. B. Klopfenstein; M.-S. Kim; H. Solheim; S. Woodward

2014-01-01

Armillaria species have a global distribution and play variable ecological roles, including causing root disease of diverse forest, ornamental and horticultural trees. Accurate identification of Armillaria species is critical to understand their distribution and ecological roles. This work focused on characterizing an unidentified Armillaria isolate from a Serbian...

Quality and Variability of Online Available Physical Therapy Protocols From Academic Orthopaedic Surgery Programs for Anterior Cruciate Ligament Reconstruction.

PubMed

Makhni, Eric C; Crump, Erica K; Steinhaus, Michael E; Verma, Nikhil N; Ahmad, Christopher S; Cole, Brian J; Bach, Bernard R

2016-08-01

To assess the quality and variability found across anterior cruciate ligament (ACL) rehabilitation protocols published online by academic orthopaedic programs. Web-based ACL physical therapy protocols from United States academic orthopaedic programs available online were included for review. Main exclusion criteria included concomitant meniscus repair, protocols aimed at pediatric patients, and failure to provide time points for the commencement or recommended completion of any protocol components. A comprehensive, custom scoring rubric was created that was used to assess each protocol for the presence or absence of various rehabilitation components, as well as when those activities were allowed to be initiated in each protocol. Forty-two protocols were included for review from 155 U.S. academic orthopaedic programs. Only 13 protocols (31%) recommended a prehabilitation program. Five protocols (12%) recommended continuous passive motion postoperatively. Eleven protocols (26%) recommended routine partial or non-weight bearing immediately postoperatively. Ten protocols (24%) mentioned utilization of a secondary/functional brace. There was considerable variation in range of desired full-weight-bearing initiation (9 weeks), as well as in the types of strength and proprioception exercises specifically recommended. Only 8 different protocols (19%) recommended return to sport after achieving certain strength and activity criteria. Many ACL rehabilitation protocols recommend treatment modalities not supported by current reports. Moreover, high variability in the composition and time ranges of rehabilitation components may lead to confusion among patients and therapists. Level II. Copyright © 2016 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

Managing water and salinity with desalination, conveyance, conservation, waste-water treatment and reuse to counteract climate variability in Gaza

NASA Astrophysics Data System (ADS)

Rosenberg, D. E.; Aljuaidi, A. E.; Kaluarachchi, J. J.

2009-12-01

We include demands for water of different salinity concentrations as input parameters and decision variables in a regional hydro-economic optimization model. This specification includes separate demand functions for saline water. We then use stochastic non-linear programming to jointly identify the benefit maximizing set of infrastructure expansions, operational allocations, and use of different water quality types under climate variability. We present a detailed application for the Gaza Strip. The application considers building desalination and waste-water treatment plants and conveyance pipelines, initiating water conservation and leak reduction programs, plus allocating and transferring water of different qualities among agricultural, industrial, and urban sectors and among districts. Results show how to integrate a mix of supply enhancement, conservation, water quality improvement, and water quality management actions into a portfolio that can economically and efficiently respond to changes and uncertainties in surface and groundwater availability due to climate variability. We also show how to put drawn-down and saline Gaza aquifer water to more sustainable and economical use.

Mitigating Insider Sabotage and Espionage: A Review of the United States Air Force’s Current Posture

DTIC Science & Technology

2009-03-01

published on ins ider threat, to include the variables that come into play and historical case studies. Existing insider threat models are discussed ...problem, including the initial development of a logical da ta mod el and a system dynamics model. This chapter also discusses the selection of the...Finally, Chapter V provides a summary of the research along with a discussion of its conclusions and impact. Recommendations for future research

Variable power distribution for zoned regeneration of an electrically heated particulate filter

DOEpatents

Bhatia, Garima [Bangalore, IN; Gonze, Eugene V [Pinckney, MI

2012-04-03

A system includes a particulate matter (PM) filter with multiple zones, an electric heater and a control module. The electrical heater includes heater segments, which each correspond with a respective one of the zones. The electrical heater is arranged upstream from and is proximate with the PM filter. The control module selectively applies a first energy level to a first one of the zones via a first one of the heater segments to initiate regeneration in the first zone. The control module also selectively applies a second energy level that is less than the first energy level to a second one of the zones via a second one of the heater segments to initiate regeneration in the second zone.

Review of advanced radiator technologies for spacecraft power systems and space thermal control

NASA Technical Reports Server (NTRS)

Juhasz, Albert J.; Peterson, George P.

1994-01-01

A two-part overview of progress in space radiator technologies is presented. The first part reviews and compares the innovative heat-rejection system concepts proposed during the past decade, some of which have been developed to the breadboard demonstration stage. Included are space-constructable radiators with heat pipes, variable-surface-area radiators, rotating solid radiators, moving-belt radiators, rotating film radiators, liquid droplet radiators, Curie point radiators, and rotating bubble-membrane radiators. The second part summarizes a multielement project including focused hardware development under the Civil Space Technology Initiative (CSTI) High Capacity Power program carried out by the NASA Lewis Research Center and its contractors to develop lightweight space radiators in support of Space Exploration Initiative (SEI) power systems technology.

Should Age at Diagnosis Be Included as an Additional Variable in the Risk of Recurrence Classification System in Patients with Differentiated Thyroid Cancer

PubMed Central

Pitoia, Fabián; Jerkovich, Fernando; Smulever, Anabella; Brenta, Gabriela; Bueno, Fernanda; Cross, Graciela

2017-01-01

Objective To evaluate the influence of age at diagnosis on the frequency of structural incomplete response (SIR) according to the modified risk of recurrence (RR) staging system from the American Thyroid Association guidelines. Patients and Methods We performed a retrospective analysis of 268 patients with differentiated thyroid cancer (DTC) followed up for at least 3 years after initial treatment (total thyroidectomy and remnant ablation). The median follow-up in the whole cohort was 74.3 months (range: 36.1-317.9) and the median age at diagnosis was 45.9 years (range: 18-87). The association between age at diagnosis and the initial and final response to treatment was assessed with analysis of variance (ANOVA). Patients were also divided into several groups considering age younger and older than 40, 50, and 60 years. Results Age at diagnosis was not associated with either an initial or final statistically significant different SIR to treatment (p = 0.14 and p = 0.58, respectively). Additionally, we did not find any statistically significant differences when the percentages of SIR considering the classification of RR were compared between different groups of patients by using several age cutoffs. Conclusions When patients are correctly risk stratified, it seems that age at diagnosis is not involved in the frequency of having a SIR at the initial evaluation or at the final follow-up, so it should not be included as an additional variable to be considered in the RR classifications. PMID:28785543

The relationship of bone and blood lead to hypertension: Further analyses of the normative aging study data

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

Hu, H.; Kim, Rokho; Korrick, S.

1996-12-31

In an earlier report based on participants in the Veterans Administration Normative Aging Study, we found a significant association between the risk of hypertension and lead levels in tibia. To examine the possible confounding effects of education and occupation, we considered in this study five levels of education and three levels of occupation as independent variables in the statistical model. Of 1,171 active subjects seen between August 1991 and December 1994, 563 provided complete data for this analysis. In the initial logistic regression model, acre and body mass index, family history of hypertension, and dietary sodium intake, but neither cumulativemore » smoking nor alcohol ingestion, conferred increased odds ratios for being hypertensive that were statistically significant. When the lead biomarkers were added separately to this initial logistic model, tibia lead and patella lead levels were associated with significantly elevated odds ratios for hypertension. In the final backward elimination logistic regression model that included categorical variables for education and occupation, the only variables retained were body mass index, family history of hypertension, and tibia lead level. We conclude that education and occupation variables were not confounding the association between the lead biomarkers and hypertension that we reported previously. 27 refs., 3 tabs.« less

Optimization of non-thermal plasma efficiency in the simultaneous elimination of benzene, toluene, ethyl-benzene, and xylene from polluted airstreams using response surface methodology.

PubMed

Najafpoor, Ali Asghar; Jonidi Jafari, Ahmad; Hosseinzadeh, Ahmad; Khani Jazani, Reza; Bargozin, Hasan

2018-01-01

Treatment with a non-thermal plasma (NTP) is a new and effective technology applied recently for conversion of gases for air pollution control. This research was initiated to optimize the efficient application of the NTP process in benzene, toluene, ethyl-benzene, and xylene (BTEX) removal. The effects of four variables including temperature, initial BTEX concentration, voltage, and flow rate on the BTEX elimination efficiency were investigated using response surface methodology (RSM). The constructed model was evaluated by analysis of variance (ANOVA). The model goodness-of-fit and statistical significance was assessed using determination coefficients (R 2 and R 2 adj ) and the F-test. The results revealed that the R 2 proportion was greater than 0.96 for BTEX removal efficiency. The statistical analysis demonstrated that the BTEX removal efficiency was significantly correlated with the temperature, BTEX concentration, voltage, and flow rate. Voltage was the most influential variable affecting the dependent variable as it exerted a significant effect (p < 0.0001) on the response variable. According to the achieved results, NTP can be applied as a progressive, cost-effective, and practical process for treatment of airstreams polluted with BTEX in conditions of low residence time and high concentrations of pollutants.

SIVA/DIVA- INITIAL VALUE ORDINARY DIFFERENTIAL EQUATION SOLUTION VIA A VARIABLE ORDER ADAMS METHOD

NASA Technical Reports Server (NTRS)

Krogh, F. T.

1994-01-01

The SIVA/DIVA package is a collection of subroutines for the solution of ordinary differential equations. There are versions for single precision and double precision arithmetic. These solutions are applicable to stiff or nonstiff differential equations of first or second order. SIVA/DIVA requires fewer evaluations of derivatives than other variable order Adams predictor-corrector methods. There is an option for the direct integration of second order equations which can make integration of trajectory problems significantly more efficient. Other capabilities of SIVA/DIVA include: monitoring a user supplied function which can be separate from the derivative; dynamically controlling the step size; displaying or not displaying output at initial, final, and step size change points; saving the estimated local error; and reverse communication where subroutines return to the user for output or computation of derivatives instead of automatically performing calculations. The user must supply SIVA/DIVA with: 1) the number of equations; 2) initial values for the dependent and independent variables, integration stepsize, error tolerance, etc.; and 3) the driver program and operational parameters necessary for subroutine execution. SIVA/DIVA contains an extensive diagnostic message library should errors occur during execution. SIVA/DIVA is written in FORTRAN 77 for batch execution and is machine independent. It has a central memory requirement of approximately 120K of 8 bit bytes. This program was developed in 1983 and last updated in 1987.

Variability in use of voiding cystourethrogram during initial evaluation of infants with congenital hydronephrosis.

PubMed

Vemulakonda, Vijaya M; Chiang, George; Corbett, Sean T

2014-05-01

To identify geographic variability in the imaging of infants with congenital hydronephrosis at initial pediatric urologic evaluation. We performed a retrospective review of infants aged ≤ 12 months with congenital hydronephrosis seen as new patients from October 2010 to September 2011 at 3 regionally diverse pediatric urology practices: University of Virginia Hospital, Rady Children's Hospital, and Children's Hospital Colorado. Primary outcomes measured were the type and number of tests ordered at initial evaluation. Independent variables collected included the following: patient age, location, and initial ultrasound findings. Ultrasound findings were manually extracted from the attending pediatric urologist's clinic note. All other data were automatically extracted from the electronic medical record. Proportions were analyzed using Pearson's goodness of fit and Fisher exact tests. Medians were compared using the Kruskal-Wallis test. Two hundred forty-one patients met the study criteria. Median patient age was 2 months and did not differ across sites. Most patients (64.7%) had Society for Fetal Urology grade 0-2 hydronephrosis; prevalence of high-grade hydronephrosis varied across sites (P = .002). Use of voiding cystourethrography also varied across sites (17.6%-88.9%); this difference persisted when controlling for age and hydronephrosis grade (P <.05). Use of other imaging studies did not significantly differ across sites. Use of screening voiding cystourethrography for infants with congenital hydronephrosis varies across practices. This variation persists when controlling for differences in age and ultrasound findings, suggesting that regional differences in patient demographics, provider/parental preferences, or referral patterns might contribute to practice variations in the evaluation of these patients. Copyright © 2014 Elsevier Inc. All rights reserved.

[Prospective multicenter study on long-term ketogenic diet therapy for intractable childhood epilepsy].

PubMed

2013-04-01

To evaluate the efficacy and safety of long-term ketogenic diet (KD) on the children with intractable epilepsy. This was a prospective, open-label study of intractable epilepsy patients treated with the classic KD with a lipid-to-nonlipid ratio 4:1 between October 2004 and July 2011 at five Chinese epilepsy centers. A total of 299 patients were enrolled. The patients were divided into different groups according to age (including the below-1-year-old group, 1-to-3-year-old group, 3-to-6-year-old group, 6-to-10-year-old group, and over-10-year-old group), etiology (cryptogenic epilepsy, symptomatic epilepsy, and idiopathic epilepsy), and the seizure types (included infantile spasm, Lennox-Gastaut syndrome, Ohtahara syndrome, tuberous sclerosis, Dravet syndrome, generalized epilepsy, and partial epilepsy). Parents were assigned to write seizure diaries which recorded the seizure presentations, tolerability, and complications associated with the KD. Patients' weight and height were measured every week. Blood β-hydroxybutyric acid, blood sugar, and urinary ketone bodies were monitored closely. Patients were followed up through telephone calls by the nutritionists every month and regular outpatient visits or hospitalizations were recommended at all time-points which included the third, sixth and twelfth month after initiation. Efficacy was measured through seizure frequency. The variables related to the efficacy were also analyzed. SPSS 17.0 was used for all statistical analysis. At 3, 6, and 12 months after initiation, 65.9%, 44.8%, and 26.4% patients remained on the diet, and 37.4%, 26.1%, and 20.4% had a > 50% reduction in their seizure frequency, including 21.7%, 10.7%, and 11.0% who became seizure free, respectively. At 24 months after initiation, 29 patients remained on the diet, and 28 patients had a > 90% seizure reduction, including five became seizure free. At 36 months after initiation, 7 patients remained on the diet, and all of them had a > 90% seizure reduction, including five became seizure free. No significant variables were related to the efficacy. Most complications were mild and reversible by conservative treatment. Gastrointestinal disturbances were the main complications, which included vomiting, diarrhea, constipation, and abdominal cramp. Severe complications occurred in four cases, including severe metabolic disturbances and severe pneumonia. The KD is a safe and effective alternative therapy for intractable childhood epilepsy.

A two-phase sampling survey for nonresponse and its paradata to correct nonresponse bias in a health surveillance survey.

PubMed

Santin, G; Bénézet, L; Geoffroy-Perez, B; Bouyer, J; Guéguen, A

2017-02-01

The decline in participation rates in surveys, including epidemiological surveillance surveys, has become a real concern since it may increase nonresponse bias. The aim of this study is to estimate the contribution of a complementary survey among a subsample of nonrespondents, and the additional contribution of paradata in correcting for nonresponse bias in an occupational health surveillance survey. In 2010, 10,000 workers were randomly selected and sent a postal questionnaire. Sociodemographic data were available for the whole sample. After data collection of the questionnaires, a complementary survey among a random subsample of 500 nonrespondents was performed using a questionnaire administered by an interviewer. Paradata were collected for the complete subsample of the complementary survey. Nonresponse bias in the initial sample and in the combined samples were assessed using variables from administrative databases available for the whole sample, not subject to differential measurement errors. Corrected prevalences by reweighting technique were estimated by first using the initial survey alone and then the initial and complementary surveys combined, under several assumptions regarding the missing data process. Results were compared by computing relative errors. The response rates of the initial and complementary surveys were 23.6% and 62.6%, respectively. For the initial and the combined surveys, the relative errors decreased after correction for nonresponse on sociodemographic variables. For the combined surveys without paradata, relative errors decreased compared with the initial survey. The contribution of the paradata was weak. When a complex descriptive survey has a low response rate, a short complementary survey among nonrespondents with a protocol which aims to maximize the response rates, is useful. The contribution of sociodemographic variables in correcting for nonresponse bias is important whereas the additional contribution of paradata in correcting for nonresponse bias is questionable. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

Design and Development of a Real-Time Model Attitude Measurement System for Hypersonic Facilities

NASA Technical Reports Server (NTRS)

Jones, Thomas W.; Lunsford, Charles B.

2005-01-01

A series of wind tunnel tests have been conducted to evaluate a multi-camera videogrammetric system designed to measure model attitude in hypersonic facilities. The technique utilizes processed video data and applies photogrammetric principles for point tracking to compute model position including pitch, roll and yaw variables. A discussion of the constraints encountered during the design, development, and testing process, including lighting, vibration, operational range and optical access is included. Initial measurement results from the NASA Langley Research Center (LaRC) 31-Inch Mach 10 tunnel are presented.

Design and Development of a Real-Time Model Attitude Measurement System for Hypersonic Facilities

NASA Technical Reports Server (NTRS)

Jones, Thomas W.; Lunsford, Charles B.

2004-01-01

A series of wind tunnel tests have been conducted to evaluate a multi-camera videogrammetric system designed to measure model attitude in hypersonic facilities. The technique utilizes processed video data and applies photogrammetric principles for point tracking to compute model position including pitch, roll and yaw variables. A discussion of the constraints encountered during the design, development, and testing process, including lighting, vibration, operational range and optical access is included. Initial measurement results from the NASA Langley Research Center (LaRC) 31-Inch Mach 10 tunnel are presented.

Mathematical, numerical and experimental analysis of the swirling flow at a Kaplan runner outlet

NASA Astrophysics Data System (ADS)

Muntean, S.; Ciocan, T.; Susan-Resiga, R. F.; Cervantes, M.; Nilsson, H.

2012-11-01

The paper presents a novel mathematical model for a-priori computation of the swirling flow at Kaplan runners outlet. The model is an extension of the initial version developed by Susan-Resiga et al [1], to include the contributions of non-negligible radial velocity and of the variable rothalpy. Simple analytical expressions are derived for these additional data from three-dimensional numerical simulations of the Kaplan turbine. The final results, i.e. velocity components profiles, are validated against experimental data at two operating points, with the same Kaplan runner blades opening, but variable discharge.

Land - Ocean Climate Linkages and the Human Evolution - New ICDP and IODP Drilling Initiatives in the East African Rift Valley and SW Indian Ocean

NASA Astrophysics Data System (ADS)

Zahn, R.; Feibel, C.; Co-Pis, Icdp/Iodp

2009-04-01

The past 5 Ma were marked by systematic shifts towards colder climates and concomitant reorganizations in ocean circulation and marine heat transports. Some of the changes involved plate-tectonic shifts such as the closure of the Panamanian Isthmus and restructuring of the Indonesian archipelago that affected inter-ocean communications and altered the world ocean circulation. These changes induced ocean-atmosphere feedbacks with consequences for climates globally and locally. Two new ICDP and IODP drilling initiatives target these developments from the perspectives of marine and terrestrial palaeoclimatology and the human evolution. The ICDP drilling initiative HSPDP ("Hominid Sites and Paleolakes Drilling Project"; ICDP ref. no. 10/07) targets lacustrine depocentres in Ethiopia (Hadar) and Kenya (West Turkana, Olorgesailie, Magadi) to retrieve sedimentary sequences close to the places and times where various species of hominins lived over currently available outcrop records. The records will provide a spatially resolved record of the East African environmental history in conjunction with climate variability at orbital (Milankovitch) and sub-orbital (ENSO decadal) time scales. HSPDP specifically aims at (1) compiling master chronologies for outcrops around each of the depocentres; (2) assessing which aspects of the paleoenvironmental records are a function of local origin (hydrology, hydrogeology) and which are linked with regional or larger-scale signals; (3) correlating broad-scale patterns of hominin phylogeny with the global beat of climate variability and (4) correlating regional shifts in the hominin fossil and archaeological record with more local patterns of paleoenvironmental change. Ultimately the aim is to test hypotheses that link physical and cultural adaptations in the course of the hominin evolution to local environmental change and variability. The IODP initiative SAFARI ("Southern African Climates, Agulhas Warm Water Transports and Retroflection, and Interocean Exchanges"; IODP ref. no. 702-full) aims at deciphering the late Neogene ocean history of the SW Indian Ocean. SAFARI specifically targets the Agulhas Current in the SW Indian Ocean that constitutes the strongest western boundary current in the southern hemisphere oceans. The Current transports warm and saline surface waters from the tropical Indian Ocean to the southern tip of Africa. Exchanges with the atmosphere influence eastern and southern African climates including individual weather systems such as extra-tropical cyclone formation in the region and rainfall patterns. Ocean models further suggest the "leakage" of Agulhas water around South Africa into the Atlantic potentially modulates the Atlantic meridional overturning circulation (MOC) with consequences for climate globally. The SAFARI drilling initiative aims to retrieve a suite of long drill cores along the southeast African margin and in the Indian-Atlantic ocean gateway. SAFARI will shed light on the history of Agulhas Current warm water transports along the southeast African margin during the late Neogene and its linking with ocean-climate developments. Specific objectives of SAFARI are to test (1) the sensitivity of the Agulhas Current to changing climates of the Plio/Pleistocene, including upstream forcing linked with equatorial Indian Ocean changes and Indonesian Throughflow; (2) the Current's influence on eastern and southern Africa climates, including rain fall patterns and vegetation changes; (3) buoyancy transfer to the Atlantic by Agulhas leakage around southern Africa, and (4) the contribution of variable Agulhas Leakage to shifts of the Atlantic MOC during episodes of major ocean and climate reorganizations of the past 5 Ma. These studies will provide insight into the Current's influence on eastern and southern African terrestrial climates, including its possible impact on the late Neogene evolution of large mammals including hominids. The ICDP and IODP drilling campaigns will enable us to establish the linkages between the ocean climatology of the SW Indian and terrestrial climates of Eastern Africa during key periods of global climate change. Combining the ICDP records of East African terrestrial climate at key hominin sites with IODP records of marine climate variability at the SE African continental margin will help to test if pulses of hominin evolutionary innovation were linked with periods of enhanced variability of local terrestrial environments and marine climatology of the Indian Ocean. * co-PIs of the ICDP initiative HSPDP are A.S. Cohen, R. Arrowsmith, A.K. Behrensmeyer, C. Feibel, R. Johnson, Z. Kubsa, D. Olago, R. Potts, R. Renaut * co-PIs of the IODP initiative SAFARI are R. Zahn, I. Hall, R. Schneider, M. Á. Bárcena, S. Barker, A. Biastoch, Chr. Charles, J. Compton, R. Cowling, P. Diz, L. Dupont, J.-A. Flores, S. Goldstein, S. Hemming, K. Holmgren, J. Lee-Thorp, G. Knorr, C. Lear, A. Mazaud, G. Mortyn, F. Peeters, B. Preu, R. Rickaby, J. Rogers, A. Rosell-Mele, Chr. Reason, V. Spiess, M. Trauth, G. Uenzelmann-Neben, S. Weldeab, P. Ziveri

Intraseasonal variability of the West African monsoon and African easterly waves during boreal summer

NASA Astrophysics Data System (ADS)

Alaka, Ghassan J., Jr.

Substantial subseasonal variability in African easterly wave (AEW) activity and cyclogenesis frequency occurs in the main hurricane development region of the Atlantic during boreal summer. A complete understanding of intraseasonal variability in the Atlantic and west Africa during boreal summer requires analysis of how the Madden-Julian Oscillation (MJO) modulates the west African monsoon and consequently AEWs. Because the MJO is predictable a few weeks in advance, understanding how and why the MJO impacts the west African monsoon may have a profound influence on Atlantic tropical cyclone prediction. This study documents the MJO influence on the west African monsoon system during boreal summer using a variety of reanalysis and satellite datasets. This study aims to identify and explain the MJO teleconnection to the west African monsoon, and the processes that induce precipitation and AEW variability in this region. Intraseasonal west African and Atlantic convective anomalies on 30-90 day timescales are likely induced by equatorial Kelvin and Rossby waves generated in the Indian Ocean and west Pacific by the MJO. Previous studies have hypothesized that an area including the Darfur mountains and the Ethiopian highlands is an initiation region for AEWs. It is shown here that the initial MJO influence on precipitation and AEW activity in the African monsoon appears to occur in these regions, where eddy kinetic energy (EKE) anomalies first appear in advance of MJO-induced periods of enhanced and suppressed AEW activity. In the initiation region, upper tropospheric temperature anomalies are reduced, the atmosphere moistens by horizontal advection, and an eastward extension of the African easterly jet occurs in advance of the MJO wet phase of the African monsoon, when AEW activity is also enhanced. These factors all support strong precursor disturbances in the initiation region that seed the African easterly jet and contribute to downstream development of AEWs. Opposite behavior occurs in advance of the MJO dry phase. Moisture and eddy kinetic energy (EKE) budgets are examined to provide further insight as to how the MJO modulates and initiates precipitation and AEW variability in this region. In particular, meridional moisture advection anomalies foster moistening in the initiation region by anomalous flow acting across the mean moisture gradient. Additionally, positive (negative) upstream EKE tendency anomalies in advance of the MJO convective maximum (minimum) over tropical north Africa suggest wave growth (decay) near the entrance of the AEJ, while enhanced (suppressed) conversion of eddy available potential energy (EAPE) to EKE and barotropic conversion maintains downstream AEW growth (decay).

Decadal climate predictability in the southern Indian Ocean captured by SINTEX-F using a simple SST-nudging scheme.

PubMed

Morioka, Yushi; Doi, Takeshi; Behera, Swadhin K

2018-01-26

Decadal climate variability in the southern Indian Ocean has great influences on southern African climate through modulation of atmospheric circulation. Although many efforts have been made to understanding physical mechanisms, predictability of the decadal climate variability, in particular, the internally generated variability independent from external atmospheric forcing, remains poorly understood. This study investigates predictability of the decadal climate variability in the southern Indian Ocean using a coupled general circulation model, called SINTEX-F. The ensemble members of the decadal reforecast experiments were initialized with a simple sea surface temperature (SST) nudging scheme. The observed positive and negative peaks during late 1990s and late 2000s are well reproduced in the reforecast experiments initiated from 1994 and 1999, respectively. The experiments initiated from 1994 successfully capture warm SST and high sea level pressure anomalies propagating from the South Atlantic to the southern Indian Ocean. Also, the other experiments initiated from 1999 skillfully predict phase change from a positive to negative peak. These results suggest that the SST-nudging initialization has the essence to capture the predictability of the internally generated decadal climate variability in the southern Indian Ocean.

The initial glycemic variability is associated with early neurological deterioration in diabetic patients with acute ischemic stroke.

PubMed

Hui, Jiaojie; Zhang, Jianping; Mao, Xuqiang; Li, Zaiwang; Li, Xinxin; Wang, Fengyun; Wang, Tao; Yuan, Qingfang; Wang, Sunwei; Pu, Mengjia; Xi, Guangjun

2018-06-05

The association between glycemic variability and early neurological deterioration (END) in acute ischemic stroke remains unclear. This study attempted to explore whether initial glycemic variability increases END in diabetic patients with acute ischemic stroke. We enrolled type 2 diabetic patients undergoing acute ischemic stroke from November 2015 to November 2016. A total of 336 patients within 72 h from stroke onset were included. The serum glucose levels were checked four times per day during the initial 3 hospital days. The standard deviation of blood glucose (SDBG) values and the mean amplitude of glycemic excursions (MAGE) were calculated for glycemic variability. END was defined as an increase in the National Institutes of Health Stroke Scale (NIHSS) ≥ 2 points between hospital days 0 and 5. The frequencies of END and HbA1c were significantly different in subjects grouped according to tertiles of MAGE (9.09, 12.07 and 50.00%, p < 0.001 for END; 7.36 ± 1.91, 7.83 ± 1.93 and 8.56 ± 1.79, p < 0.001 for HbA1c). Compared to patients without END, patients with END had significantly higher HbA1c levels (8.30 ± 1.92 vs 7.80 ± 1.93, p = 0.043), increased SDBG (3.42 ± 1.14 vs 2.60 ± 0.96, p < 0.001), and increased MAGE (6.46 ± 2.09 vs 4.59 ± 1.91, p < 0.001). In a multivariable logistic regression, stroke etiology (OR 0.675; 95% CI 0.485-0.940, p = 0.020), baseline NIHSS (OR 1.086; 95% CI 1.004-1.175, p = 0.040), and MAGE (OR 1.479; 95% CI 1.162-1.882, p = 0.001) were significantly associated with END. Initial glycemic variability is associated with END in diabetic patients with acute ischemic stroke.

An Agenda for Research on the Sustainability of Public Health Programs

PubMed Central

Dearing, James W.

2011-01-01

Funders of programs in public health and community health are increasingly concerned about the sustainability of changes they initiate. Despite a recent increase in sustainability research and evaluation, this literature has not developed a widely used paradigm for conducting research that can accumulate into generalizable findings. We provide guidance for research and evaluation of health program sustainability, including definitions and types of sustainability, specifications and measurements of dependent variables, definitions of independent variables or factors that influence sustainability, and suggestions for designs for research and data collection. We suggest viewing sustainability research as a further stage in the translation or dissemination of research-based interventions into practice. This perspective emphasizes ongoing relationships with earlier stages of a broader diffusion framework, including adoption and implementation processes. PMID:21940916

The nature and use of prediction skills in a biological computer simulation

NASA Astrophysics Data System (ADS)

Lavoie, Derrick R.; Good, Ron

The primary goal of this study was to examine the science process skill of prediction using qualitative research methodology. The think-aloud interview, modeled after Ericsson and Simon (1984), let to the identification of 63 program exploration and prediction behaviors.The performance of seven formal and seven concrete operational high-school biology students were videotaped during a three-phase learning sequence on water pollution. Subjects explored the effects of five independent variables on two dependent variables over time using a computer-simulation program. Predictions were made concerning the effect of the independent variables upon dependent variables through time. Subjects were identified according to initial knowledge of the subject matter and success at solving three selected prediction problems.Successful predictors generally had high initial knowledge of the subject matter and were formal operational. Unsuccessful predictors generally had low initial knowledge and were concrete operational. High initial knowledge seemed to be more important to predictive success than stage of Piagetian cognitive development.Successful prediction behaviors involved systematic manipulation of the independent variables, note taking, identification and use of appropriate independent-dependent variable relationships, high interest and motivation, and in general, higher-level thinking skills. Behaviors characteristic of unsuccessful predictors were nonsystematic manipulation of independent variables, lack of motivation and persistence, misconceptions, and the identification and use of inappropriate independent-dependent variable relationships.

Automatic Information Processing and High Performance Skills: Individual Differences and Mechanisms of Performance Improvement in Search-Detection and Complex Task

DTIC Science & Technology

1992-09-01

abilities is fit along with the autoregressive process. Initially, the influences on search performance of within-group age and sex were included as control...Results: PerformanceLAbility Structure Measurement Model: Ability Structure The correlations between all the ability measures, age, and sex are...subsequent analyses for young adults. Age and sex were included as control variables. There was an age range of 15 years; this range is sufficiently large that

Continuously Variable Transmission

NASA Technical Reports Server (NTRS)

Grana, D. C.

1985-01-01

Chain slides along two cones, in novel transmission concept. Transmission includes chain drive between two splined shafts. Chain sprockets follow surfaces of two cones. As one chain sprocket moves toward smaller diameter other chain sprocket moves toward larger diameter, thereby changing "gear" ratio. Movement initiated by tension applied to chain by planetary gear mechanism. Device positive, simple, and efficient over wide range of speed ratios.

Motivational stage of change in young patients undergoing day treatment for eating disorders.

PubMed

Bustin, Lisa A; Lane-Loney, Susan E; Hollenbeak, Christopher S; Ornstein, Rollyn M

2013-01-01

The objective was to determine whether motivation to change is significantly altered over the course of partial hospitalization in children and adolescents with eating disorders (EDs). This study was a retrospective chart review of 30 sets of adolescents and their parents who completed the Motivational Stage of Change for Adolescents Recovering from an Eating Disorder (MSCARED) at both intake and discharge from partial hospitalization. The main outcome variables included change in stage of change (SOC) for patients and their parents. Secondary outcomes included correlations between SOC and other baseline variables, as well as changes in SOC and psychological test scores. The SOC was significantly higher at discharge than at intake in both the patients and parents, but the two groups were not in agreement at discharge. The change in the SOC was correlated with change in Children's Eating Attitudes Test scores. Assessment of decisional balance showed correlations with SOC. Age, change in weight, and psychiatric diagnoses did not correlate with initial SOC. The MSCARED may be a useful tool for monitoring young ED patients' psychological improvements with day treatment. Initial SOC is not predictive of treatment outcomes.

The costs of turnover in nursing homes.

PubMed

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

2009-10-01

Turnover rates in nursing homes have been persistently high for decades, ranging upwards of 100%. To estimate the net costs associated with turnover of direct care staff in nursing homes. DATA AND SAMPLE: Nine hundred two nursing homes in California in 2005. Data included Medicaid cost reports, the Minimum Data Set, Medicare enrollment files, Census, and Area Resource File. We estimated total cost functions, which included in addition to exogenous outputs and wages, the facility turnover rate. Instrumental variable limited information maximum likelihood techniques were used for estimation to deal with the endogeneity of turnover and costs. 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 instrumental variable estimate of turnover costs was negative and significant (P = 0.039). The marginal cost savings associated with a 10% point increase in turnover for an average facility was $167,063 or 2.9% of annual total costs. 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.

Linear perturbations in spherically symmetric dust cosmologies including a cosmological constant

NASA Astrophysics Data System (ADS)

Meyer, Sven; Bartelmann, Matthias

2017-12-01

We study the dynamical behaviour of gauge-invariant linear perturbations in spherically symmetric dust cosmologies including a cosmological constant. In contrast to spatially homogeneous FLRW models, the reduced degree of spatial symmetry causes a non-trivial dynamical coupling of gauge-invariant quantities already at first order perturbation theory and the strength and influence of this coupling on the spacetime evolution is investigated here. We present results on the underlying dynamical equations augmented by a cosmological constant and integrate them numerically. We also present a method to derive cosmologically relevant initial variables for this setup. Estimates of angular power spectra for each metric variable are computed and evaluated on the central observer's past null cone. By comparing the full evolution to the freely evolved initial profiles, the coupling strength will be determined for a best fit radially inhomogeneous patch obtained in previous works (see [1]). We find that coupling effects are not noticeable within the cosmic variance limit and can therefore safely be neglected for a relevant cosmological scenario. On the contrary, we find very strong coupling effects in a best fit spherical void model matching the distance redshift relation of SNe which is in accordance with previous findings using parametric void models.

A Funding Initiative for Community-Based Participatory Research: Lessons from the Harvard Catalyst Seed Grants

PubMed Central

Tendulkar, Shalini A.; Chu, Jocelyn; Opp, Jennifer; Geller, Alan; DiGirolamo, Ann; Gandelman, Ediss; Grullon, Milagro; Patil, Pratima; King, Stacey; Hacker, Karen

2013-01-01

Background The National Institutes of Health–funded Clinical and Translational Science Awards (CTSA) have increasingly focused on community-engaged research and funded investigators for community-based participatory research (CBPR). However, because CBPR is a collaborative process focused on community-identified research topics, the Harvard CTSA and its Community Advisory Board (CERAB) funded community partners through a CBPR initiative. Objectives We describe lessons learned from this seed grants initiative designed to stimulate community–academic CBPR partnerships. Methods The CBPR program of the Harvard CTSA and the CERAB developed this initiative and each round incorporated participant and advisory feedback toward program improvement. Lessons Learned Although this initiative facilitated relevant and innovative research, challenges included variable community research readiness, insufficient project time, and difficulties identifying investigators for new partnerships. Conclusion Seed grants can foster innovative CBPR projects. Similar initiatives should consider preliminary assessments of community research readiness as well as strategies for meaningful academic researcher engagement. PMID:21441667

Probabilistic Structural Analysis of SSME Turbopump Blades: Probabilistic Geometry Effects

NASA Technical Reports Server (NTRS)

Nagpal, V. K.

1985-01-01

A probabilistic study was initiated to evaluate the precisions of the geometric and material properties tolerances on the structural response of turbopump blades. To complete this study, a number of important probabilistic variables were identified which are conceived to affect the structural response of the blade. In addition, a methodology was developed to statistically quantify the influence of these probabilistic variables in an optimized way. The identified variables include random geometric and material properties perturbations, different loadings and a probabilistic combination of these loadings. Influences of these probabilistic variables are planned to be quantified by evaluating the blade structural response. Studies of the geometric perturbations were conducted for a flat plate geometry as well as for a space shuttle main engine blade geometry using a special purpose code which uses the finite element approach. Analyses indicate that the variances of the perturbations about given mean values have significant influence on the response.

Prospective Analysis of the Influence of Sport and Educational Factors on the Prevalence and Initiation of Smoking in Older Adolescents from Croatia

PubMed Central

Zenic, Natasa; Ban, Djivo; Jurisic, Sanja; Cubela, Mladen; Rodek, Jelena; Ostojic, Ljerka; Jelicic, Mario; Bianco, Antonino; Sekulic, Damir

2017-01-01

The prevalence of smoking among Croatian adolescents is alarmingly high, but no previous study has prospectively examined the sport- and academic-factors associated with smoking and smoking initiation. This study aimed to prospectively examine the associations between scholastic (educational) achievement and sport factors and smoking in 16- to 18-year-old adolescents. This two-year prospective cohort study included 644 adolescents who were 16 years of age at baseline (46% females). Baseline testing was implemented at the beginning of the 3rd year of high school (September 2014) when participants were 16 years old. Follow-up testing was completed at the end of the fourth year of high school, which occurred 20 months later. The evaluated predictor variables were educational-achievement- and sport-related-factors. The outcome variables were (i) smoking at baseline; (ii) smoking at follow-up; and (iii) smoking initiation over the course of the study. We assessed the associations between predictors and outcomes using logistic regression models adjusted for age, gender, socioeconomic status, and conflict with parents. The educational variables were consistently associated with smoking, with lower grade-point-average (Baseline: odd ratio (OR): 2.01, 95% confidence interval (CI): 1.61–2.55; Follow-up: 1.59, 1.31–1.94), more frequent absence from school (Baseline: OR: 1.40, 95% CI: 1.19–1.69; Follow-up: 1.30, 1.08–1.58), and lower behavioral grades (Baseline: OR: 1.80, 95% CI: 1.10–2.89; Follow-up: 1.57, 1.03–2.41) in children who smoke. Adolescents who reported quitting sports were at greater odds of being smokers (Baseline: 2.07, 1.31–3.32; Follow-up: 1.66, 1.09–2.56). Sport competitive achievement at baseline was protective against smoking initiation during following two-year period (0.45, 0.21–0.91). While the influence of the educational variables on smoking initiation has been found to be established earlier; sport achievement was identified as a significant protective factor against initiating smoking in older adolescents. Results should be used in development of an anti-smoking preventive campaign in older adolescents. PMID:28425977

Effects of Ensemble Configuration on Estimates of Regional Climate Uncertainties

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

Goldenson, N.; Mauger, G.; Leung, L. R.

Internal variability in the climate system can contribute substantial uncertainty in climate projections, particularly at regional scales. Internal variability can be quantified using large ensembles of simulations that are identical but for perturbed initial conditions. Here we compare methods for quantifying internal variability. Our study region spans the west coast of North America, which is strongly influenced by El Niño and other large-scale dynamics through their contribution to large-scale internal variability. Using a statistical framework to simultaneously account for multiple sources of uncertainty, we find that internal variability can be quantified consistently using a large ensemble or an ensemble ofmore » opportunity that includes small ensembles from multiple models and climate scenarios. The latter also produce estimates of uncertainty due to model differences. We conclude that projection uncertainties are best assessed using small single-model ensembles from as many model-scenario pairings as computationally feasible, which has implications for ensemble design in large modeling efforts.« less

Force encoding in muscle spindles during stretch of passive muscle

PubMed Central

Blum, Kyle P.; Zytnicki, Daniel

2017-01-01

Muscle spindle proprioceptive receptors play a primary role in encoding the effects of external mechanical perturbations to the body. During externally-imposed stretches of passive, i.e. electrically-quiescent, muscles, the instantaneous firing rates (IFRs) of muscle spindles are associated with characteristics of stretch such as length and velocity. However, even in passive muscle, there are history-dependent transients of muscle spindle firing that are not uniquely related to muscle length and velocity, nor reproduced by current muscle spindle models. These include acceleration-dependent initial bursts, increased dynamic response to stretch velocity if a muscle has been isometric, and rate relaxation, i.e., a decrease in tonic IFR when a muscle is held at a constant length after being stretched. We collected muscle spindle spike trains across a variety of muscle stretch kinematic conditions, including systematic changes in peak length, velocity, and acceleration. We demonstrate that muscle spindle primary afferents in passive muscle fire in direct relationship to muscle force-related variables, rather than length-related variables. Linear combinations of whole muscle-tendon force and the first time derivative of force (dF/dt) predict the entire time course of transient IFRs in muscle spindle Ia afferents during stretch (i.e., lengthening) of passive muscle, including the initial burst, the dynamic response to lengthening, and rate relaxation following lengthening. Similar to acceleration scaling found previously in postural responses to perturbations, initial burst amplitude scaled equally well to initial stretch acceleration or dF/dt, though later transients were only described by dF/dt. The transient increase in dF/dt at the onset of lengthening reflects muscle short-range stiffness due to cross-bridge dynamics. Our work demonstrates a critical role of muscle cross-bridge dynamics in history-dependent muscle spindle IFRs in passive muscle lengthening conditions relevant to the detection and sensorimotor response to mechanical perturbations to the body, and to previously-described history-dependence in perception of limb position. PMID:28945740

Force encoding in muscle spindles during stretch of passive muscle.

PubMed

Blum, Kyle P; Lamotte D'Incamps, Boris; Zytnicki, Daniel; Ting, Lena H

2017-09-01

Muscle spindle proprioceptive receptors play a primary role in encoding the effects of external mechanical perturbations to the body. During externally-imposed stretches of passive, i.e. electrically-quiescent, muscles, the instantaneous firing rates (IFRs) of muscle spindles are associated with characteristics of stretch such as length and velocity. However, even in passive muscle, there are history-dependent transients of muscle spindle firing that are not uniquely related to muscle length and velocity, nor reproduced by current muscle spindle models. These include acceleration-dependent initial bursts, increased dynamic response to stretch velocity if a muscle has been isometric, and rate relaxation, i.e., a decrease in tonic IFR when a muscle is held at a constant length after being stretched. We collected muscle spindle spike trains across a variety of muscle stretch kinematic conditions, including systematic changes in peak length, velocity, and acceleration. We demonstrate that muscle spindle primary afferents in passive muscle fire in direct relationship to muscle force-related variables, rather than length-related variables. Linear combinations of whole muscle-tendon force and the first time derivative of force (dF/dt) predict the entire time course of transient IFRs in muscle spindle Ia afferents during stretch (i.e., lengthening) of passive muscle, including the initial burst, the dynamic response to lengthening, and rate relaxation following lengthening. Similar to acceleration scaling found previously in postural responses to perturbations, initial burst amplitude scaled equally well to initial stretch acceleration or dF/dt, though later transients were only described by dF/dt. The transient increase in dF/dt at the onset of lengthening reflects muscle short-range stiffness due to cross-bridge dynamics. Our work demonstrates a critical role of muscle cross-bridge dynamics in history-dependent muscle spindle IFRs in passive muscle lengthening conditions relevant to the detection and sensorimotor response to mechanical perturbations to the body, and to previously-described history-dependence in perception of limb position.

Clotting Factor Changes during the First Cycle of Oral Contraceptive Use

PubMed Central

Westhoff, Carolyn L.; Eisenberger, Andrew; Tang, Rosalind; Cremers, Serge; Grossman, Lisa V.; Pike, Malcolm C.

2016-01-01

Objectives The risk of venous thromboembolism (VTE) is highest during the initial months of oral contraceptive (OC) use. We sought to evaluate the extent of hemostatic variable changes during the initial OC cycle and if such changes are related to systemic ethinyl estradiol (EE2) exposure. Study Design Participants provided multiple blood samples during a 21-day OC cycle (30 mcg EE2; 150 mcg levonorgestrel) and after a single dose following a wash-out period. Analytes included D-dimer, factor VIII activity, protein C total antigen and the hepatic proteins corticosteroid- and sex-hormone-binding globulins (CBG and SHBG). EE2 pharmacokinetic analyses related to the 24 hours after the first OC tablet (OC1) and at steady state (OC21). Results Seventeen women completed the study. D-dimer more than doubled by OC6 (p = 0.013) and remained elevated at OC21 (p=0.012). D-dimer levels within women varied widely from day-to-day. Factor VIII increased 27% by OC2 (p < 0.001), but declined to a 9% increase by OC21. Protein C increased only 6%. EE2 steady-state area-under-the-curve ranged from 488 to 1103 pg·h/mL; higher levels were not correlated with greater increases in clotting variables. CBG and SHBG increased significantly, but were not significantly correlated with levels of EE2 or with the hemostatic variables. Conclusions D-dimer increases during the first OC cycle were at least as great as increases seen with longer OC use. These results provide support for the increased VTE risk during initial OC use. The extreme variability in D-dimer levels may be an important component of this risk. PMID:26452328

The effect of latent heat release on synoptic-to-planetary wave interactions and its implication for satellite observations: Theoretical modeling

NASA Technical Reports Server (NTRS)

Branscome, Lee E.; Bleck, Rainer; Obrien, Enda

1990-01-01

The project objectives are to develop process models to investigate the interaction of planetary and synoptic-scale waves including the effects of latent heat release (precipitation), nonlinear dynamics, physical and boundary-layer processes, and large-scale topography; to determine the importance of latent heat release for temporal variability and time-mean behavior of planetary and synoptic-scale waves; to compare the model results with available observations of planetary and synoptic wave variability; and to assess the implications of the results for monitoring precipitation in oceanic-storm tracks by satellite observing systems. Researchers have utilized two different models for this project: a two-level quasi-geostrophic model to study intraseasonal variability, anomalous circulations and the seasonal cycle, and a 10-level, multi-wave primitive equation model to validate the two-level Q-G model and examine effects of convection, surface processes, and spherical geometry. It explicitly resolves several planetary and synoptic waves and includes specific humidity (as a predicted variable), moist convection, and large-scale precipitation. In the past year researchers have concentrated on experiments with the multi-level primitive equation model. The dynamical part of that model is similar to the spectral model used by the National Meteorological Center for medium-range forecasts. The model includes parameterizations of large-scale condensation and moist convection. To test the validity of results regarding the influence of convective precipitation, researchers can use either one of two different convective schemes in the model, a Kuo convective scheme or a modified Arakawa-Schubert scheme which includes downdrafts. By choosing one or the other scheme, they can evaluate the impact of the convective parameterization on the circulation. In the past year researchers performed a variety of initial-value experiments with the primitive-equation model. Using initial conditions typical of climatological winter conditions, they examined the behavior of synoptic and planetary waves growing in moist and dry environments. Surface conditions were representative of a zonally averaged ocean. They found that moist convection associated with baroclinic wave development was confined to the subtropics.

Scheduling the blended solution as industrial CO2 absorber in separation process by back-propagation artificial neural networks.

PubMed

Abdollahi, Yadollah; Sairi, Nor Asrina; Said, Suhana Binti Mohd; Abouzari-lotf, Ebrahim; Zakaria, Azmi; Sabri, Mohd Faizul Bin Mohd; Islam, Aminul; Alias, Yatimah

2015-11-05

It is believe that 80% industrial of carbon dioxide can be controlled by separation and storage technologies which use the blended ionic liquids absorber. Among the blended absorbers, the mixture of water, N-methyldiethanolamine (MDEA) and guanidinium trifluoromethane sulfonate (gua) has presented the superior stripping qualities. However, the blended solution has illustrated high viscosity that affects the cost of separation process. In this work, the blended fabrication was scheduled with is the process arranging, controlling and optimizing. Therefore, the blend's components and operating temperature were modeled and optimized as input effective variables to minimize its viscosity as the final output by using back-propagation artificial neural network (ANN). The modeling was carried out by four mathematical algorithms with individual experimental design to obtain the optimum topology using root mean squared error (RMSE), R-squared (R(2)) and absolute average deviation (AAD). As a result, the final model (QP-4-8-1) with minimum RMSE and AAD as well as the highest R(2) was selected to navigate the fabrication of the blended solution. Therefore, the model was applied to obtain the optimum initial level of the input variables which were included temperature 303-323 K, x[gua], 0-0.033, x[MDAE], 0.3-0.4, and x[H2O], 0.7-1.0. Moreover, the model has obtained the relative importance ordered of the variables which included x[gua]>temperature>x[MDEA]>x[H2O]. Therefore, none of the variables was negligible in the fabrication. Furthermore, the model predicted the optimum points of the variables to minimize the viscosity which was validated by further experiments. The validated results confirmed the model schedulability. Accordingly, ANN succeeds to model the initial components of the blended solutions as absorber of CO2 capture in separation technologies that is able to industries scale up. Copyright © 2015 Elsevier B.V. All rights reserved.

Initial testing of a variable-stroke Stirling engine

NASA Technical Reports Server (NTRS)

Thieme, L. G.

1985-01-01

In support of the U.S. Department of Energy's Stirling Engine Highway Vehicle Systems Program, NASA Lewis Research Center is evaluating variable-stroke control for Stirling engines. The engine being tested is the Advenco Stirling engine; this engine was manufactured by Philips Research Laboratories of the Netherlands and uses a variable-angle swash-plate drive to achieve variable stroke operation. The engine is described, initial steady-state test data taken at Lewis are presented, a major drive system failure and subsequent modifications are described. Computer simulation results are presented to show potential part-load efficiency gains with variable-stroke control.

Adding Recognition Discriminability Index to the Delayed Recall Is Useful to Predict Conversion from Mild Cognitive Impairment to Alzheimer's Disease in the Alzheimer's Disease Neuroimaging Initiative.

PubMed

Russo, María J; Campos, Jorge; Vázquez, Silvia; Sevlever, Gustavo; Allegri, Ricardo F

2017-01-01

Background: Ongoing research is focusing on the identification of those individuals with mild cognitive impairment (MCI) who are most likely to convert to Alzheimer's disease (AD). We investigated whether recognition memory tasks in combination with delayed recall measure of episodic memory and CSF biomarkers can predict MCI to AD conversion at 24-month follow-up. Methods: A total of 397 amnestic-MCI subjects from Alzheimer's disease Neuroimaging Initiative were included. Logistic regression modeling was done to assess the predictive value of all RAVLT measures, risk factors such as age, sex, education, APOE genotype, and CSF biomarkers for progression to AD. Estimating adjusted odds ratios was used to determine which variables would produce an optimal predictive model, and whether adding tests of interaction between the RAVLT Delayed Recall and recognition measures (traditional score and d-prime) would improve prediction of the conversion from a-MCI to AD. Results: 112 (28.2%) subjects developed dementia and 285 (71.8%) subjects did not. Of the all included variables, CSF Aβ1-42 levels, RAVLT Delayed Recall, and the combination of RAVLT Delayed Recall and d-prime were predictive of progression to AD (χ 2 = 38.23, df = 14, p < 0.001). Conclusions: The combination of RAVLT Delayed Recall and d-prime measures may be predictor of conversion from MCI to AD in the ADNI cohort, especially in combination with amyloid biomarkers. A predictive model to help identify individuals at-risk for dementia should include not only traditional episodic memory measures (delayed recall or recognition), but also additional variables (d-prime) that allow the homogenization of the assessment procedures in the diagnosis of MCI.

Adding Recognition Discriminability Index to the Delayed Recall Is Useful to Predict Conversion from Mild Cognitive Impairment to Alzheimer's Disease in the Alzheimer's Disease Neuroimaging Initiative

PubMed Central

Russo, María J.; Campos, Jorge; Vázquez, Silvia; Sevlever, Gustavo; Allegri, Ricardo F.; Weiner, Michael W.

2017-01-01

Background: Ongoing research is focusing on the identification of those individuals with mild cognitive impairment (MCI) who are most likely to convert to Alzheimer's disease (AD). We investigated whether recognition memory tasks in combination with delayed recall measure of episodic memory and CSF biomarkers can predict MCI to AD conversion at 24-month follow-up. Methods: A total of 397 amnestic-MCI subjects from Alzheimer's disease Neuroimaging Initiative were included. Logistic regression modeling was done to assess the predictive value of all RAVLT measures, risk factors such as age, sex, education, APOE genotype, and CSF biomarkers for progression to AD. Estimating adjusted odds ratios was used to determine which variables would produce an optimal predictive model, and whether adding tests of interaction between the RAVLT Delayed Recall and recognition measures (traditional score and d-prime) would improve prediction of the conversion from a-MCI to AD. Results: 112 (28.2%) subjects developed dementia and 285 (71.8%) subjects did not. Of the all included variables, CSF Aβ1-42 levels, RAVLT Delayed Recall, and the combination of RAVLT Delayed Recall and d-prime were predictive of progression to AD (χ2 = 38.23, df = 14, p < 0.001). Conclusions: The combination of RAVLT Delayed Recall and d-prime measures may be predictor of conversion from MCI to AD in the ADNI cohort, especially in combination with amyloid biomarkers. A predictive model to help identify individuals at-risk for dementia should include not only traditional episodic memory measures (delayed recall or recognition), but also additional variables (d-prime) that allow the homogenization of the assessment procedures in the diagnosis of MCI. PMID:28344552

Comparative study of flare control laws. [optimal control of b-737 aircraft approach and landing

NASA Technical Reports Server (NTRS)

Nadkarni, A. A.; Breedlove, W. J., Jr.

1979-01-01

A digital 3-D automatic control law was developed to achieve an optimal transition of a B-737 aircraft between various initial glid slope conditions and the desired final touchdown condition. A discrete, time-invariant, optimal, closed-loop control law presented for a linear regulator problem, was extended to include a system being acted upon by a constant disturbance. Two forms of control laws were derived to solve this problem. One method utilized the feedback of integral states defined appropriately and augmented with the original system equations. The second method formulated the problem as a control variable constraint, and the control variables were augmented with the original system. The control variable constraint control law yielded a better performance compared to feedback control law for the integral states chosen.

Racial/ethnic differences in breastfeeding duration among WIC-eligible families.

PubMed

Sparks, Patrice Johnelle

2011-01-01

This research documented racial/ethnic differences in breastfeeding duration among mothers from seven diverse racial/ethnic groups in rural and urban areas of the United States that initiated breastfeeding among income and categorically eligible WIC participants. Using data from the Longitudinal 9-Month-Preschool Restricted-Use data file of the Early Childhood Longitudinal Study-Birth Cohort, this research first assessed racial/ethnic differences in breastfeeding initiation and duration, maternal and child health characteristics, social service usage, and sociodemographic characteristics. Next, breastfeeding survivorship and Cox proportional hazards models were estimated to assess potential racial/ethnic disparities in breastfeeding duration once these control variables were accounted for in multiple variable models. Breastfeeding initiation rates and breastfeeding durations of 6 months were lower among WIC-eligible mothers compared with all mothers. WIC-eligible, foreign-born Mexican-Origin Hispanic (FBMOH) mothers were most likely to breastfeed for 6 months. Breastfeeding duration rates dropped quickly after 4 months of duration among WIC-eligible mothers that initiated. Two crossover patterns in breastfeeding durations were noted among 1) FBMOH and non-Hispanic Black mothers and 2) Asian and Native American mothers. A FBMOH breastfeeding duration advantage was noted compared with non-Hispanic White mothers once all control variables were included in the Cox proportional hazard models. No other racial/ethnic disparities in breastfeeding duration were noted. More attention to educational programs and broad forms of support as part of WIC are needed to help reach the breastfeeding duration goals of Healthy People 2010 and continued support of the Loving Support Peer Counseling Program may serve as an ideal policy for local WIC offices. Copyright © 2011 Jacobs Institute of Women's Health. Published by Elsevier Inc. All rights reserved.

Association Between Facility-Level Utilization of Non-pharmacologic Chronic Pain Treatment and Subsequent Initiation of Long-Term Opioid Therapy.

PubMed

Carey, Evan P; Nolan, Charlotte; Kerns, Robert D; Ho, P Michael; Frank, Joseph W

2018-05-01

Expert guidelines recommend non-pharmacologic treatments and non-opioid medications for chronic pain and recommend against initiating long-term opioid therapy (LTOT). We examined whether veterans with incident chronic pain receiving care at facilities with greater utilization of non-pharmacologic treatments and non-opioid medications are less likely to initiate LTOT. Retrospective cohort study PARTICIPANTS: Veterans receiving primary care from a Veterans Health Administration facility with incident chronic pain between 1/1/2010 and 12/31/2015 based on either of 2 criteria: (1) persistent moderate-to-severe patient-reported pain and (2) diagnoses "likely to represent" chronic pain. The independent variable was facility-level utilization of pain-related treatment modalities (non-pharmacologic, non-opioid medications, LTOT) in the prior calendar year. The dependent variable was patient-level initiation of LTOT (≥ 90 days within 365 days) in the subsequent year, adjusting for patient characteristics. Among 1,094,569 veterans with incident chronic pain from 2010 to 2015, there was wide facility-level variation in utilization of 10 pain-related treatment modalities, including initiation of LTOT (median, 16%; range, 5-32%). Veterans receiving care at facilities with greater utilization of non-pharmacologic treatments were less likely to initiate LTOT in the year following incident chronic pain. Conversely, veterans receiving care at facilities with greater non-opioid and opioid medication utilization were more likely to initiate LTOT; this association was strongest for past year facility-level LTOT initiation (adjusted rate ratio, 2.10; 95% confidence interval, 2.06-2.15, top vs. bottom quartile of facility-level LTOT initiation in prior calendar year). Facility-level utilization patterns of non-pharmacologic, non-opioid, and opioid treatments for chronic pain are associated with subsequent patient-level initiation of LTOT among veterans with incident chronic pain. Further studies should seek to understand facility-level variation in chronic pain care and to identify facility-level utilization patterns that are associated with improved patient outcomes.

The influence of primary caregivers on the sexual behavior of early adolescents.

PubMed

Rose, Allison; Koo, Helen P; Bhaskar, Brinda; Anderson, Karen; White, Gregory; Jenkins, Renee R

2005-08-01

To describe rates of sexual intercourse initiation, anticipated level of sexual activity in the next 12 months, and other risk behaviors among fifth graders and to examine parental factors associated with such behaviors. This study is based on a cross-sectional, self-administered survey conducted with a nonrandom sample of 408 fifth graders and their caregivers. Children answered questions regarding sexual intercourse initiation, anticipated sexual activity in the next 12 months, and involvement in other risk behaviors. Caregivers answered questions about parenting factors such as monitoring behaviors, parent-child relationship quality, and parent-child communication. Bivariate and multivariable analyses examined the association of these variables with the adolescents' behaviors. Almost 5% of girls and 17% of boys reported they had engaged in sexual intercourse. Only 34% of girls and 13% of boys said they did not expect to engage in any type of sexual contact in the next 12 months if they were going with someone they "liked a lot." Parental factors associated with fewer risk behaviors and expected sexual behaviors included higher levels of monitoring, fewer communication barriers, less permissive attitudes regarding adolescent sexual behavior, higher relationship quality with child, having fewer than five children in the household, higher levels of education, and being employed. Significant gender interactions were found for several variables. Adolescents are initiating sexual intercourse at extremely young ages. To delay early sexual activity and prevent adolescent pregnancy, prevention efforts must begin during the elementary school years and include those who raise and care for the adolescent.

Factors predicting survival in amyotrophic lateral sclerosis patients on non-invasive ventilation.

PubMed

Gonzalez Calzada, Nuria; Prats Soro, Enric; Mateu Gomez, Lluis; Giro Bulta, Esther; Cordoba Izquierdo, Ana; Povedano Panades, Monica; Dorca Sargatal, Jordi; Farrero Muñoz, Eva

2016-01-01

Non invasive ventilation (NIV) improves quality of life and extends survival in amyotrophic lateral sclerosis (ALS) patients. However, few data exist about the factors related to survival. We intended to assess the predictive factors that influence survival in patients after NIV initiation. Patients who started NIV from 2000 to 2014 and were tolerant (compliance ≥ 4 hours) were included; demographic, disease related and respiratory variables at NIV initiation were analysed. Statistical analysis was performed using the Kaplan-Meier test and Cox proportional hazard models. 213 patients were included with median survival from NIV initiation of 13.5 months. In univariate analysis, the identified risk factors for mortality were severity of bulbar involvement (HR 2), Forced Vital Capacity (FVC) % (HR 0.99) and ALSFRS-R (HR 0.97). Multivariate analysis showed that bulbar involvement (HR 1.92) and ALSFRS-R (HR 0.97) were independent predictive factors of survival in patients on NIV. In our study, the two prognostic factors in ALS patients following NIV were the severity of bulbar involvement and ALSFRS-R at the time on NIV initiation. A better assessment of bulbar involvement, including evaluation of the upper airway, and a careful titration on NIV are necessary to optimize treatment efficacy.

Comparison of repaglinide and metformin monotherapy as an initial therapy in Chinese patients with newly diagnosed type 2 diabetes mellitus.

PubMed

Fang, Fu-Sheng; Gong, Yan-Ping; Li, Chun-Lin; Li, Jian; Tian, Hui; Huang, Wei; Wang, Liang-Chen; Li, Lin

2014-06-01

We aimed to compare the effect of repaglinide and metformin monotherapy as an initial therapy in Chinese patients with newly diagnosed type 2 diabetes mellitus (T2DM). In this 15-week, open-labelled, parallel-controlled, randomised study, 60 Chinese drug-naive patients with newly diagnosed T2DM were randomised (2:1) to receive repaglinide or metformin monotherapy. Primary endpoint was change in HbA1c from baseline to the end of the trial. Secondary endpoints included changes in glycaemic variability, insulin sensitivity and β-cell function. Patients in both repaglinide and metformin groups achieved significant reductions in HbA1c (-1.8 ± 1.5 vs -1.6 ± 1.5%), FPG (fasting blood glucose) (-1.7 ± 1.7 vs -2.1 ± 1.7  mmol/l) and 2-h PPG (post-prandial glucose) (-3.8 ± 3.1 vs -3.8 ± 3.6  mmol/l), with no statistical differences between the groups. Glycaemic variability, glucose infusion rate and β-cell function were all significantly improved from baseline in the two groups (all P<0.05), without any statistical differences in the improvement between the groups. Repaglinide and metformin achieved comparable efficacy in improving glycaemic control, reducing glycaemic variability, enhancing insulin sensitivity and ameliorating β-cell function. Therefore, repaglinide is an optional agent for initial therapy in Chinese patients with newly diagnosed T2DM. © 2014 European Society of Endocrinology.

Phonological effects in handwriting production: evidence from the implicit priming paradigm.

PubMed

Afonso, Olivia; Álvarez, Carlos J

2011-11-01

In the present article, we report 3 experiments using the odd-man-out variant of the implicit priming paradigm, aimed at determining the role played by phonological information during the handwriting process. Participants were asked to write a small set of words learned in response to prompts. Within each block, response words could share initial segments (constant homogeneous) or not (heterogeneous). Also, 2 variable homogeneous blocks were created by including a response word that did not share orthographic onset with the other response (odd-man-out). This odd-man-out could be phonologically related to the targets or not. Experiment 1 showed a preparation effect in the constant homogeneous condition, which disappeared (spoil effect) in the variable condition not phonologically related. However, no spoil effect was found when the odd-man-out shared the phonological initial segment with the targets. In Experiment 2, we obtained a spoil effect in the variable phonologically related condition, but it was significantly smaller than in the variable not phonologically related condition. The effects observed in Experiment 2 vanished in Experiment 3 under articulatory suppression, suggesting that they originated at a sublexical level. These findings suggest that phonological sublexical information is used during handwriting and provide evidence that the implicit priming paradigm (and the odd-man-out version of this) is a suitable tool for handwriting production research.

Dynamic rupture modeling with laboratory-derived constitutive relations

USGS Publications Warehouse

Okubo, P.G.

1989-01-01

A laboratory-derived state variable friction constitutive relation is used in the numerical simulation of the dynamic growth of an in-plane or mode II shear crack. According to this formulation, originally presented by J.H. Dieterich, frictional resistance varies with the logarithm of the slip rate and with the logarithm of the frictional state variable as identified by A.L. Ruina. Under conditions of steady sliding, the state variable is proportional to (slip rate)-1. Following suddenly introduced increases in slip rate, the rate and state dependencies combine to produce behavior which resembles slip weakening. When rupture nucleation is artificially forced at fixed rupture velocity, rupture models calculated with the state variable friction in a uniformly distributed initial stress field closely resemble earlier rupture models calculated with a slip weakening fault constitutive relation. Model calculations suggest that dynamic rupture following a state variable friction relation is similar to that following a simpler fault slip weakening law. However, when modeling the full cycle of fault motions, rate-dependent frictional responses included in the state variable formulation are important at low slip rates associated with rupture nucleation. -from Author

Studying the Variability of Bright Stars with the CONCAM Sky Monitoring Network

NASA Astrophysics Data System (ADS)

Pereira, W. E.; Nemiroff, R. J.; Rafert, J. B.; Perez-Ramirez, D.

2001-12-01

CONCAMs have now been deployed at some of the world's major observatories including KPNO in Arizona, Mauna Kea in Hawaii, and Wise Observatory in Israel. Data from these mobile, inexpensive and continuous sky cameras, consisting of a fish-eye lens mated to a CCD camera and run by a laptop, has been ever-increasing. Initial efforts to carry out photometric analysis of CONCAM fits images have now been fortified by a more automated technique of analyzing this data. Results of such analyses - variability of several bright stars, in particular, are presented, as well as the use of these cameras as cloud monitors to remote observers.

Understanding the Interdependencies Between Composition, Microstructure, and Continuum Variables and Their Influence on the Fracture Toughness of α/β-Processed Ti-6Al-4V

NASA Astrophysics Data System (ADS)

Collins, P. C.; Koduri, S.; Dixit, V.; Fraser, H. L.

2018-03-01

The fracture toughness of a material depends upon the material's composition and microstructure, as well as other material properties operating at the continuum level. The interrelationships between these variables are complex, and thus difficult to interpret, especially in multi-component, multi-phase ductile engineering alloys such as α/β-processed Ti-6Al-4V (nominal composition, wt pct). Neural networks have been used to elucidate how variables such as composition and microstructure influence the fracture toughness directly ( i.e., via a crack initiation or propagation mechanism)—and independent of the influence of the same variables influence on the yield strength and plasticity of the material. The variables included in the models and analysis include (i) alloy composition, specifically, Al, V, O, and Fe; (ii) materials microstructure, including phase fractions and average sizes of key microstructural features; (iii) the yield strength and reduction in area obtained from uniaxial tensile tests; and (iv) an assessment of the degree to which plane strain conditions were satisfied by including a factor related to the plane strain thickness. Once trained, virtual experiments have been conducted which permit the determination of each variable's functional dependency on the resulting fracture toughness. Given that the database includes both K 1 C and K Q values, as well as the in-plane component of the stress state of the crack tip, it is possible to quantitatively assess the effect of sample thickness on K Q and the degree to which the K Q and K 1 C values may vary. These interpretations drawn by comparing multiple neural networks have a significant impact on the general understanding of how the microstructure influences the fracture toughness in ductile materials, as well as an ability to predict the fracture toughness of α/β-processed Ti-6Al-4V.

Initialization, conceptualization, and application in the generalized (fractional) calculus.

PubMed

Lorenzo, Carl F; Hartley, Tom T

2007-01-01

This paper provides a formalized basis for initialization in the fractional calculus. The intent is to make the fractional calculus readily accessible to engineering and the sciences. A modified set of definitions for the fractional calculus is provided which formally include the effects of initialization. Conceptualizations of fractional derivatives and integrals are shown. Physical examples of the basic elements from electronics are presented along with examples from dynamics, material science, viscoelasticity, filtering, instrumentation, and electrochemistry to indicate the broad application of the theory and to demonstrate the use of the mathematics. The fundamental criteria for a generalized calculus established by Ross (1974) are shown to hold for the generalized fractional calculus under appropriate conditions. A new generalized form for the Laplace transform of the generalized differintegral is derived. The concept of a variable structure (order) differintegral is presented along with initial efforts toward meaningful definitions.

Cortical Action Potential Backpropagation Explains Spike Threshold Variability and Rapid-Onset Kinetics

PubMed Central

Yu, Yuguo; Shu, Yousheng; McCormick, David A.

2008-01-01

Neocortical action potential responses in vivo are characterized by considerable threshold variability, and thus timing and rate variability, even under seemingly identical conditions. This finding suggests that cortical ensembles are required for accurate sensorimotor integration and processing. Intracellularly, trial-to-trial variability results not only from variation in synaptic activities, but also in the transformation of these into patterns of action potentials. Through simultaneous axonal and somatic recordings and computational simulations, we demonstrate that the initiation of action potentials in the axon initial segment followed by backpropagation of these spikes throughout the neuron results in a distortion of the relationship between the timing of synaptic and action potential events. In addition, this backpropagation also results in an unusually high rate of rise of membrane potential at the foot of the action potential. The distortion of the relationship between the amplitude time course of synaptic inputs and action potential output caused by spike back-propagation results in the appearance of high spike threshold variability at the level of the soma. At the point of spike initiation, the axon initial segment, threshold variability is considerably less. Our results indicate that spike generation in cortical neurons is largely as expected by Hodgkin—Huxley theory and is more precise than previously thought. PMID:18632930

Alternative Approaches to Land Initialization for Seasonal Precipitation and Temperature Forecasts

NASA Technical Reports Server (NTRS)

Koster, Randal; Suarez, Max; Liu, Ping; Jambor, Urszula

2004-01-01

The seasonal prediction system of the NASA Global Modeling and Assimilation Office is used to generate ensembles of summer forecasts utilizing realistic soil moisture initialization. To derive the realistic land states, we drive offline the system's land model with realistic meteorological forcing over the period 1979-1993 (in cooperation with the Global Land Data Assimilation System project at GSFC) and then extract the state variables' values on the chosen forecast start dates. A parallel series of forecast ensembles is performed with a random (though climatologically consistent) set of land initial conditions; by comparing the two sets of ensembles, we can isolate the impact of land initialization on forecast skill from that of the imposed SSTs. The base initialization experiment is supplemented with several forecast ensembles that use alternative initialization techniques. One ensemble addresses the impact of minimizing climate drift in the system through the scaling of the initial conditions, and another is designed to isolate the importance of the precipitation signal from that of all other signals in the antecedent offline forcing. A third ensemble includes a more realistic initialization of the atmosphere along with the land initialization. The impact of each variation on forecast skill is quantified.

Positive Wigner functions render classical simulation of quantum computation efficient.

PubMed

Mari, A; Eisert, J

2012-12-07

We show that quantum circuits where the initial state and all the following quantum operations can be represented by positive Wigner functions can be classically efficiently simulated. This is true both for continuous-variable as well as discrete variable systems in odd prime dimensions, two cases which will be treated on entirely the same footing. Noting the fact that Clifford and Gaussian operations preserve the positivity of the Wigner function, our result generalizes the Gottesman-Knill theorem. Our algorithm provides a way of sampling from the output distribution of a computation or a simulation, including the efficient sampling from an approximate output distribution in the case of sampling imperfections for initial states, gates, or measurements. In this sense, this work highlights the role of the positive Wigner function as separating classically efficiently simulable systems from those that are potentially universal for quantum computing and simulation, and it emphasizes the role of negativity of the Wigner function as a computational resource.

Early markers of adult obesity: a review

PubMed Central

Brisbois, T D; Farmer, A P; McCargar, L J

2012-01-01

Summary The purpose of this review was to evaluate factors in early childhood (≤5 years of age) that are the most significant predictors of the development of obesity in adulthood. Factors of interest included exposures/insults in the prenatal period, infancy and early childhood, as well as other socio-demographic variables such as socioeconomic status (SES) or birth place that could impact all three time periods. An extensive electronic and systematic search initially resulted in 8,880 citations, after duplicates were removed. Specific inclusion and exclusion criteria were set, and following two screening processes, 135 studies were retained for detailed abstraction and analysis. A total of 42 variables were associated with obesity in adulthood; however, of these, only seven variables may be considered as potential early markers of obesity based on the reported associations. Possible early markers of obesity included maternal smoking and maternal weight gain during pregnancy. Probable early markers of obesity included maternal body mass index, childhood growth patterns (early rapid growth and early adiposity rebound), childhood obesity and father's employment (a proxy measure for SES in many studies). Health promotion programmes/agencies should consider these factors as reasonable targets to reduce the risk of adult obesity. PMID:22171945

Precipitation response to the current ENSO variability in a warming world

NASA Astrophysics Data System (ADS)

Bonfils, C.; Santer, B. D.; Phillips, T. J.; Marvel, K.; Leung, L.

2013-12-01

The major triggers of past and recent droughts include large modes of variability, such as ENSO, as well as specific and persistent patterns of sea surface temperature anomalies (SSTAs; Hoerling and Kumar, 2003, Shin et al. 2010, Schubert et al. 2009). However, alternative drought initiators are also anticipated in response to increasing greenhouse gases, potentially changing the relative contribution of ocean variability as drought initiator. They include the intensification of the current zonal wet-dry patterns (the thermodynamic mechanism, Held and Soden, 2006), a latitudinal redistribution of global precipitation (the dynamical mechanism, Seager et al. 2007, Seidel et al. 2008, Scheff and Frierson 2008) and a reduction of local soil moisture and precipitation recycling (the land-atmosphere argument). Our ultimate goal is to investigate whether the relative contribution of those mechanisms change over time in response to global warming. In this study, we first perform an EOF analysis of the 1900-1999 time series of observed global SST field and identify a simple ENSO-like (ENSOL) mode of SST variability. We show that this mode is well spatially and temporally correlated with observed worldwide regional precipitation and drought variability. We then develop concise metrics to examine the fidelity with which the CMIP5 coupled global climate models (CGCMs) capture this particular ENSO-like mode in the current climate, and their ability to replicate the observed teleconnections with precipitation. Based on the CMIP5 model projections of future climate change, we finally analyze the potential temporal variations in ENSOL to be anticipated under further global warming, as well as their associated teleconnections with precipitation (pattern, amplitude, and total response). Overall, our approach allows us to determine what will be the effect of the current ENSO-like variability (i.e., as measured with instrumental observations) on precipitation in a warming world. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344, and is supported, among others, by C.B. Early Career Research Program award.

Understanding the mathematics and science achievement and growth trajectories of high ability high school students using hierarchical linear modeling

NASA Astrophysics Data System (ADS)

Belen-Ferrer, Bellasanta

2009-12-01

This study used longitudinal data and individual, family, and academic-related matriculation variables to examine trends in initial status and growth trajectories in overall academics, mathematics, and science achievement among 224 high ability high school Asian students. Results indicate that females have an advantage in both initial status and growth rates in overall academics and science. None of the family variables entered in the models were found to be significantly related to overall academics grade point average. All available matriculation variables entered into the models explained less than or at most about half the variance in initial achievement status and growth rate in overall academics and science but not in mathematics. These results strongly imply that other factors, notably family and school and/or classroom-related variables, not measured by the ones used in the models could explain the expected variance in initial status and growth rate of the students especially in Mathematics.

The stigma of having psychological problems: relations with engagement, working alliance, and depression in psychotherapy.

PubMed

Kendra, Matthew S; Mohr, Jonathan J; Pollard, Jeffrey W

2014-12-01

The stigma of having psychological problems is a barrier to seeking mental health treatment, but little research has examined whether this stigma influences the experiences of those in treatment. In a sample of 42 psychotherapy clients, we explored links over the first few sessions between 2 facets of stigma (self-stigma and perceived public stigma) and 3 variables germane to the therapeutic process (depression, working alliance, and engagement). Initial self-stigma (SS) level was positively associated with initial depression, negatively associated with initial working alliance, and unrelated to initial engagement. Initial perceived public stigma (PPS) level was unrelated to initial levels in the 3 outcome variables. Initial SS and PPS levels were both generally unrelated to linear changes in the outcomes over the initial phase of counseling. Relations between stigma and outcome variables often differed within- and between-persons. For example, the association between PPS and engagement was negative at the between-person level but positive at the within-person level. Finally, on average, PPS decreased over the first few sessions but SS remained constant. Such findings may help therapists better understand the role of stigma in their clinical work, and stimulate research examining how to address stigmatization in psychotherapy.

Utility of combinations of biomarkers, cognitive markers, and risk factors to predict conversion from mild cognitive impairment to Alzheimer disease in patients in the Alzheimer's disease neuroimaging initiative.

PubMed

Gomar, Jesus J; Bobes-Bascaran, Maria T; Conejero-Goldberg, Concepcion; Davies, Peter; Goldberg, Terry E

2011-09-01

Biomarkers have become increasingly important in understanding neurodegenerative processes associated with Alzheimer disease. Markers include regional brain volumes, cerebrospinal fluid measures of pathological Aβ1-42 and total tau, cognitive measures, and individual risk factors. To determine the discriminative utility of different classes of biomarkers and cognitive markers by examining their ability to predict a change in diagnostic status from mild cognitive impairment to Alzheimer disease. Longitudinal study. We analyzed the Alzheimer's Disease Neuroimaging Initiative database to study patients with mild cognitive impairment who converted to Alzheimer disease (n = 116) and those who did not convert (n = 204) within a 2-year period. We determined the predictive utility of 25 variables from all classes of markers, biomarkers, and risk factors in a series of logistic regression models and effect size analyses. The Alzheimer's Disease Neuroimaging Initiative public database. Primary outcome measures were odds ratios, pseudo- R(2)s, and effect sizes. In comprehensive stepwise logistic regression models that thus included variables from all classes of markers, the following baseline variables predicted conversion within a 2-year period: 2 measures of delayed verbal memory and middle temporal lobe cortical thickness. In an effect size analysis that examined rates of decline, change scores for biomarkers were modest for 2 years, but a change in an everyday functional activities measure (Functional Assessment Questionnaire) was considerably larger. Decline in scores on the Functional Assessment Questionnaire and Trail Making Test, part B, accounted for approximately 50% of the predictive variance in conversion from mild cognitive impairment to Alzheimer disease. Cognitive markers at baseline were more robust predictors of conversion than most biomarkers. Longitudinal analyses suggested that conversion appeared to be driven less by changes in the neurobiologic trajectory of the disease than by a sharp decline in functional ability and, to a lesser extent, by declines in executive function.

Variations in thematic mapper spectra of soil related to tillage and crop residue management - Initial evaluation

NASA Technical Reports Server (NTRS)

Seeley, M. W.; Ruschy, D. L.; Linden, D. R.

1983-01-01

A cooperative research project was initiated in 1982 to study differences in thematic mapper spectral characteristics caused by variable tillage and crop residue practices. Initial evaluations of radiometric data suggest that spectral separability of variably tilled soils can be confounded by moisture and weathering effects. Separability of bare tilled soils from those with significant amounts of corn residue is enhanced by wet conditions, but still possible under dry conditions when recent tillage operations have occurred. In addition, thematic mapper data may provide an alternative method to study the radiant energy balance at the soil surface in conjunction with variable tillage systems.

Effect of process variables on the quality attributes of briquettes from wheat, oat, canola and barley

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

Jaya Shankar Tumuluru

2011-08-01

Effect of process variables on the quality attributes of briquettes from wheat, oat, canola and barley straw Jaya Shankar Tumuluru*, L. G. Tabil, Y. Song, K. L. Iroba and V. Meda Biomass is a renewable energy source and environmentally friendly substitute for fossil fuels such as coal and petroleum products. Major limitation of biomass for successful energy application is its low bulk density, which makes it very difficult and costly to transport and handle. To overcome this limitation, biomass has to be densified. The commonly used technologies for densification of biomass are pelletization and briquetting. Briquetting offers many advantages atmore » it can densify larger particles sizes of biomass at higher moisture contents. Briquetting is influenced by a number of feedstock and process variables such as moisture content, particle size distribution, and some operating variables such as temperature and densification pressure. In the present study, experiments were designed and conducted based on Box-Behnken design to produce briquettes using barley, wheat, canola and barley straws. A laboratory scale hydraulic briquette press was used for the present study. The experimental process variables and their levels used in the present study were pressure levels (7.5, 10, 12.5 MPa), three levels of temperature (90, 110, 130 C), at three moisture content levels (9, 12, 15% w.b.), and three levels of particle size (19.1, 25.04, 31.75 mm). The quality variables studied includes moisture content, initial density and final briquette density after two weeks of storage, size distribution index and durability. The raw biomass was initially chopped and size reduced using a hammer mill. The ground biomass was conditioned at different moisture contents and was further densified using laboratory hydraulic press. For each treatment combination, ten briquettes were manufactured at a residence time of about 30 s after compression pressure setpoint was achieved. After compression, the initial dimensions and the final dimensions after 2 weeks of storage in controlled environment of all the samples were measured. Durability, dimensional stability, and moisture content tests were conducted after two weeks of storage of the briquettes produced. Initial results indicated that moisture content played a significant role on briquettes durability, stability, and density. Low moisture content of the straws (7-12%) gave more durable briquettes. Briquette density increased with increasing pressure depending on the moisture content value. The axial expansion was more significant than the lateral expansion, which in some cases tended to be nil depending on the material and operating variables. Further data analysis is in progress in order to understand the significance of the process variables based on ANOVA. Regression models were developed to predict the changes in quality of briquettes with respect of the process variables under study. Keywords: Herbaceous biomass, densification, briquettes, density, durability, dimensional stability, ANOVA and regression equations« less

High neuroticism at age 20 predicts history of mental disorders and low self-esteem at age 35.

PubMed

Lönnqvist, Jan-Erik; Verkasalo, Markku; Mäkinen, Seppo; Henriksson, Markus

2009-07-01

The authors assessed whether neuroticism in emerging adulthood predicts mental disorders and self-esteem in early adulthood after controlling for possible confounding variables. A sample of 69 male military conscripts was initially assessed at age 20 and again as civilians at age 35. The initial assessment included a psychiatric interview, objective indicators of conscript competence, an intellectual performance test, and neuroticism questionnaires. The follow-up assessment included a Structured Clinical Interview for DSM-IV (SCID; First, Spitzer, Gibbon, & Williams, 1996) and the Rosenberg Self-Esteem Scale (Rosenberg, 1965). Neuroticism predicted future mental disorders and low self-esteem beyond more objective indicators of adjustment. The results support the use of neuroticism as a predictor of future mental disorders, even over periods of time when personality is subject to change.

Nonlinear Dynamic Models in Advanced Life Support

NASA Technical Reports Server (NTRS)

Jones, Harry

2002-01-01

To facilitate analysis, ALS systems are often assumed to be linear and time invariant, but they usually have important nonlinear and dynamic aspects. Nonlinear dynamic behavior can be caused by time varying inputs, changes in system parameters, nonlinear system functions, closed loop feedback delays, and limits on buffer storage or processing rates. Dynamic models are usually cataloged according to the number of state variables. The simplest dynamic models are linear, using only integration, multiplication, addition, and subtraction of the state variables. A general linear model with only two state variables can produce all the possible dynamic behavior of linear systems with many state variables, including stability, oscillation, or exponential growth and decay. Linear systems can be described using mathematical analysis. Nonlinear dynamics can be fully explored only by computer simulations of models. Unexpected behavior is produced by simple models having only two or three state variables with simple mathematical relations between them. Closed loop feedback delays are a major source of system instability. Exceeding limits on buffer storage or processing rates forces systems to change operating mode. Different equilibrium points may be reached from different initial conditions. Instead of one stable equilibrium point, the system may have several equilibrium points, oscillate at different frequencies, or even behave chaotically, depending on the system inputs and initial conditions. The frequency spectrum of an output oscillation may contain harmonics and the sums and differences of input frequencies, but it may also contain a stable limit cycle oscillation not related to input frequencies. We must investigate the nonlinear dynamic aspects of advanced life support systems to understand and counter undesirable behavior.

A predictive model for diagnosing bipolar disorder based on the clinical characteristics of major depressive episodes in Chinese population.

PubMed

Gan, Zhaoyu; Diao, Feici; Wei, Qinling; Wu, Xiaoli; Cheng, Minfeng; Guan, Nianhong; Zhang, Ming; Zhang, Jinbei

2011-11-01

A correct timely diagnosis of bipolar depression remains a big challenge for clinicians. This study aimed to develop a clinical characteristic based model to predict the diagnosis of bipolar disorder among patients with current major depressive episodes. A prospective study was carried out on 344 patients with current major depressive episodes, with 268 completing 1-year follow-up. Data were collected through structured interviews. Univariate binary logistic regression was conducted to select potential predictive variables among 19 initial variables, and then multivariate binary logistic regression was performed to analyze the combination of risk factors and build a predictive model. Receiver operating characteristic (ROC) curve was plotted. Of 19 initial variables, 13 variables were preliminarily selected, and then forward stepwise exercise produced a final model consisting of 6 variables: age at first onset, maximum duration of depressive episodes, somatalgia, hypersomnia, diurnal variation of mood, irritability. The correct prediction rate of this model was 78% (95%CI: 75%-86%) and the area under the ROC curve was 0.85 (95%CI: 0.80-0.90). The cut-off point for age at first onset was 28.5 years old, while the cut-off point for maximum duration of depressive episode was 7.5 months. The limitations of this study include small sample size, relatively short follow-up period and lack of treatment information. Our predictive models based on six clinical characteristics of major depressive episodes prove to be robust and can help differentiate bipolar depression from unipolar depression. Copyright © 2011 Elsevier B.V. All rights reserved.

Predictors of early breastfeeding initiation among mothers of children under 24 months of age in rural part of West Ethiopia.

PubMed

Hailemariam, Tsedeke Wolde; Adeba, Emiru; Sufa, Alem

2015-10-21

The World Health Organization recommends initiation of breastfeeding within the first hour after childbirth. In developing countries alone, early initiation of breastfeeding could save as many as 1.45 million lives each year by reducing deaths mainly due to diarrheal disorders and lower respiratory tract infections in children. The current study aimed to determine the rate and the predictors of breastfeeding initiation in East Wollega Zones of West Ethiopia. A community-based, cross-sectional study was conducted from April to May 2014 among 594 mothers who had children less than 24 months. Multi stage cluster sampling method was used to select the study population. Eligible mothers were invited to interview using pretested questionnaires to gather data regarding sociodemographics, health-related variables, breastfeeding initiation, and current breastfeeding practices. A multivariable logistic regression analysis was used to identify independent predictors of early initiation of breastfeeding after controlling for confounding variables. A sample of 593 mothers was included in the study. Breastfeeding was initiated by 83.1 % of mothers within the first hour of childbirth. Being a housewife (AOR (95 % CI) = 2.48 (1.54- 3.99)) and infant received colostrum (AOR (95 % CI) =2.22 (1.08-4.55)) were significant positive predictors for early breastfeeding initiation as revealed by logistic regression. The multivariable logistic regression analysis showed that the mothers who had no radio and/or TV in the household (AOR (95 % CI = 0.55 (0.35-0.88)), were not exposure to health information (AOR (95 % CI) = 0.44 (0.25-0.75)), and infants were provided with prelacteal feeds (AOR (95 % CI)=0.30 (0.14-0.65)) were less likely to initiate breastfeeding. The rate of timely initiation of breastfeeding was high. Breastfeeding promotion program is essential to encourage the practice of timely initiation of breastfeeding, and reduce the practice of providing prelacteal feeds within three days of life. Thus appropriate health information is vital to boost early initiation of breastfeeding.

Decadal predictions of Southern Ocean sea ice : testing different initialization methods with an Earth-system Model of Intermediate Complexity

NASA Astrophysics Data System (ADS)

Zunz, Violette; Goosse, Hugues; Dubinkina, Svetlana

2013-04-01

The sea ice extent in the Southern Ocean has increased since 1979 but the causes of this expansion have not been firmly identified. In particular, the contribution of internal variability and external forcing to this positive trend has not been fully established. In this region, the lack of observations and the overestimation of internal variability of the sea ice by contemporary General Circulation Models (GCMs) make it difficult to understand the behaviour of the sea ice. Nevertheless, if its evolution is governed by the internal variability of the system and if this internal variability is in some way predictable, a suitable initialization method should lead to simulations results that better fit the reality. Current GCMs decadal predictions are generally initialized through a nudging towards some observed fields. This relatively simple method does not seem to be appropriated to the initialization of sea ice in the Southern Ocean. The present study aims at identifying an initialization method that could improve the quality of the predictions of Southern Ocean sea ice at decadal timescales. We use LOVECLIM, an Earth-system Model of Intermediate Complexity that allows us to perform, within a reasonable computational time, the large amount of simulations required to test systematically different initialization procedures. These involve three data assimilation methods: a nudging, a particle filter and an efficient particle filter. In a first step, simulations are performed in an idealized framework, i.e. data from a reference simulation of LOVECLIM are used instead of observations, herein after called pseudo-observations. In this configuration, the internal variability of the model obviously agrees with the one of the pseudo-observations. This allows us to get rid of the issues related to the overestimation of the internal variability by models compared to the observed one. This way, we can work out a suitable methodology to assess the efficiency of the initialization procedures tested. It also allows us determine the upper limit of improvement that can be expected if more sophisticated initialization methods are used in decadal prediction simulations and if models have an internal variability agreeing with the observed one. Furthermore, since pseudo-observations are available everywhere at any time step, we also analyse the differences between simulations initialized with a complete dataset of pseudo-observations and the ones for which pseudo-observations data are not assimilated everywhere. In a second step, simulations are realized in a realistic framework, i.e. through the use of actual available observations. The same data assimilation methods are tested in order to check if more sophisticated methods can improve the reliability and the accuracy of decadal prediction simulations, even if they are performed with models that overestimate the internal variability of the sea ice extent in the Southern Ocean.

CEOS Ocean Variables Enabling Research and Applications for Geo (COVERAGE)

NASA Astrophysics Data System (ADS)

Tsontos, V. M.; Vazquez, J.; Zlotnicki, V.

2017-12-01

The CEOS Ocean Variables Enabling Research and Applications for GEO (COVERAGE) initiative seeks to facilitate joint utilization of different satellite data streams on ocean physics, better integrated with biological and in situ observations, including near real-time data streams in support of oceanographic and decision support applications for societal benefit. COVERAGE aligns with programmatic objectives of CEOS (the Committee on Earth Observation Satellites) and the missions of GEO-MBON (Marine Biodiversity Observation Network) and GEO-Blue Planet, which are to advance and exploit synergies among the many observational programs devoted to ocean and coastal waters. COVERAGE is conceived of as 3 year pilot project involving international collaboration. It focuses on implementing technologies, including cloud based solutions, to provide a data rich, web-based platform for integrated ocean data delivery and access: multi-parameter observations, easily discoverable and usable, organized by disciplines, available in near real-time, collocated to a common grid and including climatologies. These will be complemented by a set of value-added data services available via the COVERAGE portal including an advanced Web-based visualization interface, subsetting/extraction, data collocation/matchup and other relevant on demand processing capabilities. COVERAGE development will be organized around priority use cases and applications identified by GEO and agency partners. The initial phase will be to develop co-located 25km products from the four Ocean Virtual Constellations (VCs), Sea Surface Temperature, Sea Level, Ocean Color, and Sea Surface Winds. This aims to stimulate work among the ocean VCs while developing products and system functionality based on community recommendations. Such products as anomalies from a time mean, would build on the theme of applications with a relevance to CEOS/GEO mission and vision. Here we provide an overview of the COVERAGE initiative with an emphasis on international collaborative aspects entailed with the intent of soliciting community feedback as we develop and implement

Effects of additional data on Bayesian clustering.

PubMed

Yamazaki, Keisuke

2017-10-01

Hierarchical probabilistic models, such as mixture models, are used for cluster analysis. These models have two types of variables: observable and latent. In cluster analysis, the latent variable is estimated, and it is expected that additional information will improve the accuracy of the estimation of the latent variable. Many proposed learning methods are able to use additional data; these include semi-supervised learning and transfer learning. However, from a statistical point of view, a complex probabilistic model that encompasses both the initial and additional data might be less accurate due to having a higher-dimensional parameter. The present paper presents a theoretical analysis of the accuracy of such a model and clarifies which factor has the greatest effect on its accuracy, the advantages of obtaining additional data, and the disadvantages of increasing the complexity. Copyright © 2017 Elsevier Ltd. All rights reserved.

Under-Five Mortality in High Focus States in India: A District Level Geospatial Analysis

PubMed Central

Kumar, Chandan; Singh, Prashant Kumar; Rai, Rajesh Kumar

2012-01-01

Background This paper examines if, when controlling for biophysical and geographical variables (including rainfall, productivity of agricultural lands, topography/temperature, and market access through road networks), socioeconomic and health care indicators help to explain variations in the under-five mortality rate across districts from nine high focus states in India. The literature on this subject is inconclusive because the survey data, upon which most studies of child mortality rely, rarely include variables that measure these factors. This paper introduces these variables into an analysis of 284 districts from nine high focus states in India. Methodology/Principal Findings Information on the mortality indicator was accessed from the recently conducted Annual Health Survey of 2011 and other socioeconomic and geographic variables from Census 2011, District Level Household and Facility Survey (2007–08), Department of Economics and Statistics Divisions of the concerned states. Displaying high spatial dependence (spatial autocorrelation) in the mortality indicator (outcome variable) and its possible predictors used in the analysis, the paper uses the Spatial-Error Model in an effort to negate or reduce the spatial dependence in model parameters. The results evince that the coverage gap index (a mixed indicator of district wise coverage of reproductive and child health services), female literacy, urbanization, economic status, the number of newborn care provided in Primary Health Centers in the district transpired as significant correlates of under-five mortality in the nine high focus states in India. The study identifies three clusters with high under-five mortality rate including 30 districts, and advocates urgent attention. Conclusion Even after controlling the possible biophysical and geographical variables, the study reveals that the health program initiatives have a major role to play in reducing under-five mortality rate in the high focus states in India. PMID:22629412

Age of smoking initiation among adolescents in Africa.

PubMed

Veeranki, Sreenivas P; John, Rijo M; Ibrahim, Abdallah; Pillendla, Divya; Thrasher, James F; Owusu, Daniel; Ouma, Ahmed E O; Mamudu, Hadii M

2017-01-01

To estimate prevalence and identify correlates of age of smoking initiation among adolescents in Africa. Data (n = 16,519) were obtained from nationally representative Global Youth Tobacco Surveys in nine West African countries. Study outcome was adolescents' age of smoking initiation categorized into six groups: ≤7, 8 or 9, 10 or 11, 12 or 13, 14 or 15 and never-smoker. Explanatory variables included sex, parental or peer smoking behavior, exposure to tobacco industry promotions, and knowledge about smoking harm. Weighted multinomial logit models were conducted to determine correlates associated with adolescents' age of smoking initiation. Age of smoking initiation was as early as ≤7 years; prevalence estimates ranged from 0.7 % in Ghana at 10 or 11 years age to 9.6 % in Cote d'Ivoire at 12 or 13 years age. Males, exposures to parental or peer smoking, and industry promotions were identified as significant correlates. West African policymakers should adopt a preventive approach consistent with the World Health Organization Framework Convention on Tobacco Control to prevent an adolescent from initiating smoking and developing into future regular smokers.

Virtual Airport Simulation Technology: Perceptions of Airport Operations Initial Training Program Variables and Effectiveness for Airside Professional Competence

ERIC Educational Resources Information Center

DeCarlo, Jeffrey

2010-01-01

Air travel is expected to grow by a factor of 2 to 3 times by 2025 and people working in the aviation system, including airport personnel, pilots, and air traffic controllers, must be able to safely and efficiently operate in this arena ("NextGen"). In response to the personnel training and education requirements concomitant with "NextGen,"…

A Simplified Analytic Investigation of the Riverside Effects of Sediment Diversions

DTIC Science & Technology

2013-09-01

demonstrated that the river bed consists of a sand layer of variable thickness, underlain by erosion resistant strata (either relict glacial deposits...following analysis. Simplifications and Initial Conditions. Consider a river modeled as a wide rectangular channel of constant width (Figure 1). The...CHETN-VII-13 September 2013 14  Short term effects include the redistribution of sediment by erosion upstream of the diversion to deposition

Automated predesign of aircraft

NASA Technical Reports Server (NTRS)

Poe, C. C., Jr.; Kruse, G. S.; Tanner, C. J.; Wilson, P. J.

1978-01-01

Program uses multistation structural-synthesis to size and design box-beam structures for transport aircraft. Program optimizes static strength and scales up to satisfy fatigue and fracture criteria. It has multimaterial capability and library of materials properties, including advanced composites. Program can be used to evaluate impact on weight of variables such as materials, types of construction, structural configurations, minimum gage limits, applied loads, fatigue lives, crack-growth lives, initial crack sizes, and residual strengths.

An ecological approach to evaluating a system of care program: dollars making sense.

PubMed

Green, Denise M; Twill, Sarah E; Nackerud, Larry; Holosko, Michael

2014-01-01

System of care (SOC) models in North America were developed in response to the needs of children with a severe emotional disturbance. Such children experience problems across life spheres including issues at home that put them at risk of abuse and neglect, difficulties at school including special education classification and dropping-out, and involvement with the juvenile courts. SOC evaluations and research suggests that an overreliance of evaluative research efforts on standardized scales and preconceived measurable outcomes have resulted in a loss of other important data. This study's confirmatory and holistic approach to evaluation illuminates important information concerning commonly ignored variables when using traditional evaluation models. The evaluative research study described focuses on three often overlooked behavioral variables in one SOC initiative, KidsNet Georgia, of Rockdale County, GA. These variables are: (a) using cohort analysis over time; (b) costing out services utilized; and (c) focusing on behavioral indicators and chance over time. The evaluative strategy, data collection, data, and cost analysis are discussed along with implications for practice with severe emotional disturbance youth and their families.

BLM Density Management and Riparian Buffer Study: Establishment Report and Study Plan

USGS Publications Warehouse

Cissel, John H.; Anderson, P.D.; Olson, Deanna H.; Puettmann, Klaus; Berryman, Shanti; Chan, Samuel; Thompson, Charley

2006-01-01

The Bureau of Land Management (BLM), Pacific Northwest Research Station (PNW), U.S. Geological Survey (USGS), and Oregon State University (OSU) established the BLM Density Management and Riparian Buffer Study (DMS) in 1994 to demonstrate and test options for young stand management to meet Northwest Forest Plan objectives in western Oregon. The primary objectives of the DMS are to evaluate the effects of alternative forest density management treatments in young stands on the development of important late-successional forest habitat attributes and to assess the combined effects of density management and alternative riparian buffer widths on aquatic and riparian ecosystems. The DMS consists of three integrated studies: initial thinning, rethinning, and riparian buffer widths. The initial thinning study was installed in 50- to 80-year-old stands that had never been commercially thinned. Four stand treatments of 30-60 acres each were established at each of seven study sites: (1) unthinned control, (2) high density retention [120 trees per acre (TPA)], (3) moderate density retention (80 TPA), and (4) variable density retention (40-120 TPA). Small (1/4 to 1 acre in size) leave islands were included in all treatments except the control, and small patch cuts (1/4 to 1 acre in size) were included in the moderate and variable density treatments. An eighth site, Callahan Creek, contains a partial implementation of the study design. The rethinning study was installed in four 70- to 90-year-old stands that previously had been commercially thinned. Each study stand was split into two parts: one part as an untreated control and the other part as a rethinning (30-60 TPA). The riparian buffer study was nested within the moderate density retention treatment at each of the eight initial thinning study sites and two rethinning sites. Alternative riparian buffer widths included: (1) streamside retention (one tree canopy width, or 20-25 feet), (2) variable width (follows topographic and vegetative breaks, 50 feet slope distance minimum), (3) one full site-potential tree height (approximately 220 feet), and (4) two full tree heights (approximately 440 feet). A second round of density management manipulations are now being planned for implementation beginning in 2009. Stem density will be reduced in the high, moderate, and variable density treatments and most existing riparian buffers, leave islands, and patch cuts will remain in place. Remeasurement, data management, and analysis are ongoing for three long-term, core components of the DMS: vegetation, microclimate, and aquatic vertebrates. In addition, several short-term collaborative studies have been completed on these sites, including leave island effectiveness as refugia, treatment response of terrestrial and aquatic arthropods, and smaller-scale studies of fungal, lichen, and bryophyte community response. Additional collaborative studies are encouraged on DMS sites.

How do Indonesian youth perceive cigarette advertising? A cross-sectional study among Indonesian high school students

PubMed Central

Prabandari, Yayi Suryo; Dewi, Arika

2016-01-01

Background Previous studies have reported an association between cigarette advertising and smoking behavior. Although this has been reported extensively in the West, it has been reported less in Southeast Asian countries that have not completely banned tobacco advertising promotion and sponsorship (TAPS). Indonesia is the only ASEAN country that has not ratified the Framework Convention on Tobacco Control, so TAPS regulation is limited. This study aimed to assess the association between youths’ perceptions of cigarette ads and smoking initiation. Design We conducted a cross-sectional survey among 2,115 high school students aged 13–18 years in Yogyakarta, Indonesia. A self-administered questionnaire was distributed to gauge the perception of cigarette ads and initiation to smoking. We calculated the odds ratio (OR) between the perception of cigarette ads and smoking initiation, adjusting for sociodemographic and psychosocial variables. The sociodemographic variables included in the final model were age and sex. Results The final multivariate model showed an association between perception of tobacco ads encouraging youths to smoke and smoking initiation (OR 2.70) and current smoking (OR 7.63). Attitude toward TAPS was associated with smoking initiation (OR 1.51) and current smoking (OR 3.32). Exposure to cigarette ads had an association with smoking initiation only (OR 1.27) and did not have an association with current smoking. Having friends and family who smoked was associated with smoking initiation and current smoking in the final multivariate model. Smoking initiation and current smoking were also related to the susceptibility to smoke. Conclusions This study revealed that cigarette ads were perceived as encouraging youths to smoke and that smoking status was consistently associated with perception of cigarette ads targeted at youths, attitude toward TAPS, and susceptibility as well as smoking friends and family. Regulations to ban TAPS, particularly cigarette ads for preventing youths from smoking, should be adopted rapidly in Indonesia, where tobacco control remains limited. PMID:27578600

Microwave Heating of Crystals with Gold Nanoparticles and Synovial Fluid under Synthetic Skin Patches

PubMed Central

2017-01-01

Gout is a disease with elusive treatment options. Reduction of the size of l-alanine crystals as a model crystal for gouty tophi with the use of a monomode solid-state microwave was examined as a possible therapeutic aid. The effect of microwave heating on l-alanine crystals in the presence of gold nanoparticles (Au NPs) in solution and synovial fluid (SF) in a plastic pouch through a synthetic skin patch was investigated. In this regard, three experimental paradigms were employed: Paradigm 1 includes the effect of variable microwave power (5–10 W) and variable heating time (5–60 s) and Au NPs in water (20 nm size, volume of 10 μL) in a plastic pouch (1 × 2 cm2 in size). Paradigm 2 includes the effect of a variable volume of 20 nm Au NPs in a variable volume of SF up to 100 μL in a plastic pouch at a constant microwave power (10 W) for 30 s. Paradigm 3 includes the effect of constant microwave power (10 W) and microwave heating time (30 s), constant volume of Au NPs (100 μL), and variable size of Au NPs (20–200 nm) placed in a plastic pouch through a synthetic skin patch. In these experiments, an average of 60–100% reduction in the size of an l-alanine crystal (initial size = 450 μm) without damage to the synthetic skin or increasing the temperature of the samples beyond the physiological range was reported. PMID:28983527

Understanding the drivers of interprofessional collaborative practice among HIV primary care providers and case managers in HIV care programmes.

PubMed

Mavronicolas, Heather A; Laraque, Fabienne; Shankar, Arti; Campbell, Claudia

2017-05-01

Care coordination programmes are an important aspect of HIV management whose success depends largely on HIV primary care provider (PCP) and case manager collaboration. Factors influencing collaboration among HIV PCPs and case managers remain to be studied. The study objective was to test an existing theoretical model of interprofessional collaborative practice and determine which factors play the most important role in facilitating collaboration. A self-administered, anonymous mail survey was sent to HIV PCPs and case managers in New York City. An adapted survey instrument elicited information on demographic, contextual, and perceived social exchange (trustworthiness, role specification, and relationship initiation) characteristics. The dependent variable, perceived interprofessional practice, was constructed from a validated scale. A sequential block wise regression model specifying variable entry order examined the relative importance of each group of factors and of individual variables. The analysis showed that social exchange factors were the dominant drivers of collaboration. Relationship initiation was the most important predictor of interprofessional collaboration. Additional influential factors included organisational leadership support of collaboration, practice settings, and frequency of interprofessional meetings. Addressing factors influencing collaboration among providers will help public health programmes optimally design their structural, hiring, and training strategies to foster effective social exchanges and promote collaborative working relationships.

A taxonomy for mechanical ventilation: 10 fundamental maxims.

PubMed

Chatburn, Robert L; El-Khatib, Mohamad; Mireles-Cabodevila, Eduardo

2014-11-01

The American Association for Respiratory Care has declared a benchmark for competency in mechanical ventilation that includes the ability to "apply to practice all ventilation modes currently available on all invasive and noninvasive mechanical ventilators." This level of competency presupposes the ability to identify, classify, compare, and contrast all modes of ventilation. Unfortunately, current educational paradigms do not supply the tools to achieve such goals. To fill this gap, we expand and refine a previously described taxonomy for classifying modes of ventilation and explain how it can be understood in terms of 10 fundamental constructs of ventilator technology: (1) defining a breath, (2) defining an assisted breath, (3) specifying the means of assisting breaths based on control variables specified by the equation of motion, (4) classifying breaths in terms of how inspiration is started and stopped, (5) identifying ventilator-initiated versus patient-initiated start and stop events, (6) defining spontaneous and mandatory breaths, (7) defining breath sequences (8), combining control variables and breath sequences into ventilatory patterns, (9) describing targeting schemes, and (10) constructing a formal taxonomy for modes of ventilation composed of control variable, breath sequence, and targeting schemes. Having established the theoretical basis of the taxonomy, we demonstrate a step-by-step procedure to classify any mode on any mechanical ventilator. Copyright © 2014 by Daedalus Enterprises.

Development of a Statistical Model for Forecasting Episodes of Visibility Degradation in the Denver Metropolitan Area.

NASA Astrophysics Data System (ADS)

Reddy, P. J.; Barbarick, D. E.; Osterburg, R. D.

1995-03-01

In 1990, the State of Colorado implemented a visibility standard of 0.076 km1 of beta extinction for the Denver metropolitan area. Meteorologists with Colorado's Air Pollution Control Division forecast high pollution days associated with visibility impairment as well as those due to high levels of the federal criteria pollutants. Visibility forecasts are made from a few hours up to about 26 h in advance of the period of interest. Here we discuss the key microscale, mesoscale, and synoptic-scale features associated with episodes of visibility impairment. Data from special studies, case studies, and the 22 NOAA Program for Regional Observing and Forecasting Services mesonet sites have been invaluable in identifying patterns associated with extremes in visibility conditions. A preliminary statistical forecast model has been developed using variables that represent many of these patterns. Six variables were selected from an initial pool of 27 to be used in a model based on linear logistic regression. These six variables include forecast measures of snow cover, surface pressures and a surface pressure gradient in eastern Colorado, relative humidity, and 500-mb ridge position. The initial testing of the model has been encouraging. The model correctly predicted 76% of the good visibility days and 67% of the poor visibility days for a test set of 171 days.

Are state laws granting pharmacists authority to vaccinate associated with HPV vaccination rates among adolescents?

PubMed

Trogdon, Justin G; Shafer, Paul R; Shah, Parth D; Calo, William A

2016-08-31

We explored whether state laws allowing pharmacists to administer human papillomavirus (HPV) vaccinations to adolescents are associated with a higher likelihood of HPV vaccine uptake. We examined provider-reported HPV vaccination among 13-17year olds in the National Immunization Survey-Teen: 2008-2014 for girls (N=48,754) and 2010-2014 for boys (N=31,802). Outcome variables were HPV vaccine initiation (⩾1 dose) and completion (⩾3 doses). The explanatory variable of interest was a categorical variable for the type of pharmacist authority regarding HPV vaccination for adolescents (<18years) in the state: not permitted (reference), by prescription, by collaborative practice protocol, or independent authority. We ran separate difference-in-difference regression models by sex. During 2008-2014, 15 states passed laws allowing pharmacists to administer HPV vaccine to adolescents. Pharmacist authority laws were not statistically significantly associated with increased HPV vaccine initiation or completion. As currently implemented, state laws allowing pharmacists to administer HPV vaccine to adolescents were not associated with uptake. Possible explanations that need further research include restrictions on pharmacists' third-party billing ability and the lack of promotion of pharmacy vaccination services to age-eligible adolescents. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Variable Vector Countermeasure Suit (V2Suit) for space habitation and exploration.

PubMed

Duda, Kevin R; Vasquez, Rebecca A; Middleton, Akil J; Hansberry, Mitchell L; Newman, Dava J; Jacobs, Shane E; West, John J

2015-01-01

The "Variable Vector Countermeasure Suit (V2Suit) for Space Habitation and Exploration" is a novel system concept that provides a platform for integrating sensors and actuators with daily astronaut intravehicular activities to improve health and performance, while reducing the mass and volume of the physiologic adaptation countermeasure systems, as well as the required exercise time during long-duration space exploration missions. The V2Suit system leverages wearable kinematic monitoring technology and uses inertial measurement units (IMUs) and control moment gyroscopes (CMGs) within miniaturized modules placed on body segments to provide a "viscous resistance" during movements against a specified direction of "down"-initially as a countermeasure to the sensorimotor adaptation performance decrements that manifest themselves while living and working in microgravity and during gravitational transitions during long-duration spaceflight, including post-flight recovery and rehabilitation. Several aspects of the V2Suit system concept were explored and simulated prior to developing a brassboard prototype for technology demonstration. This included a system architecture for identifying the key components and their interconnects, initial identification of key human-system integration challenges, development of a simulation architecture for CMG selection and parameter sizing, and the detailed mechanical design and fabrication of a module. The brassboard prototype demonstrates closed-loop control from "down" initialization through CMG actuation, and provides a research platform for human performance evaluations to mitigate sensorimotor adaptation, as well as a tool for determining the performance requirements when used as a musculoskeletal deconditioning countermeasure. This type of countermeasure system also has Earth benefits, particularly in gait or movement stabilization and rehabilitation.

Cardiac autonomic function during sleep: effects of alcohol dependence and evidence of partial recovery with abstinence.

PubMed

de Zambotti, Massimiliano; Willoughby, Adrian R; Baker, Fiona C; Sugarbaker, David S; Colrain, Ian M

2015-06-01

Chronic alcoholism is associated with the development of cardiac and peripheral autonomic nervous system (ANS) pathology. The aim of the present study was to evaluate the extent to which recovery in ANS function could be demonstrated over the first 4 months of abstinence. Fifteen alcoholics (7 women) were studied on three occasions: within a month of detoxification, at approximately 2 months post-detox, and at 4 months post-detox. Thirteen control subjects (6 women) were also studied on three occasions with inter-study intervals matching those of the alcoholics. Six alcoholics relapsed, 48.7 ± 27.9 days following the initial PSG session. ANS function was assessed in the first part of stable non-rapid eye movement sleep. Frequency-domain power spectral analysis of heart rate variability (HRV) produced variables including: heart rate (HR), total power (TP; an index representing total HR variability), High Frequency power (HFa; an index reflecting cardiac vagal modulation), HF proportion of total power (HFprop sympathovagal balance), and HF peak frequency (HFpf; an index reflecting respiration rate). Overall, high total and high frequency variability and low sympathovagal balance and myocardial contractility are considered as desired conditions to promote cardiovascular health. At initial assessment, alcoholics had a higher HR (p < 0.001) and respiratory rate (p < 0.01), and lower vagal activity (HFa; p < 0.01) than controls. Alcoholics showed evidence of recovery in HR (p = 0.039) and HFa (p = 0.031) with 4 months of abstinence. Alcoholics with higher TP at the initial visit showed a greater improvement in TP from the initial to the 4 month follow-up session (r = 0.75, p < 0.05). Alcoholics showed substantial recovery in HR and vagal modulation of HRV with 4 months of abstinence, with evidence that the extent of recovery in HRV may be partially determined by the extent of alcohol dependence-related insult to the cardiac ANS system. These data support other studies showing recovery in a number of ANS, central nervous system, and behavioral domains with abstinence, even in those with long-term dependence. Copyright © 2015 Elsevier Inc. All rights reserved.

Inlet-engine matching for SCAR including application of a bicone variable geometry inlet

NASA Technical Reports Server (NTRS)

Wasserbauer, J. F.; Gerstenmaier, W. H.

1978-01-01

Airflow characteristics of variable cycle engines (VCE) designed for Mach 2.32 can have transonic airflow requirements as high as 1.6 times the cruise airflow. This is a formidable requirement for conventional, high performance, axisymmetric, translating centerbody mixed compression inlets. An alternate inlet is defined, where the second cone of a two cone center body collapses to the initial cone angle to provide a large off-design airflow capability, and incorporates modest centerbody translation to minimize spillage drag. Estimates of transonic spillage drag are competitive with those of conventional translating centerbody inlets. The inlet's cruise performance exhibits very low bleed requirements with good recovery and high angle of attack capability.

Modelling interactions between mitigation, adaptation and sustainable development

NASA Astrophysics Data System (ADS)

Reusser, D. E.; Siabatto, F. A. P.; Garcia Cantu Ros, A.; Pape, C.; Lissner, T.; Kropp, J. P.

2012-04-01

Managing the interdependence of climate mitigation, adaptation and sustainable development requires a good understanding of the dominant socioecological processes that have determined the pathways in the past. Key variables include water and food availability which depend on climate and overall ecosystem services, as well as energy supply and social, political and economic conditions. We present our initial steps to build a system dynamic model of nations that represents a minimal set of relevant variables of the socio- ecological development. The ultimate goal of the modelling exercise is to derive possible future scenarios and test those for their compatibility with sustainability boundaries. Where dynamics go beyond sustainability boundaries intervention points in the dynamics can be searched.

An explanatory model of academic achievement based on aptitudes, goal orientations, self-concept and learning strategies.

PubMed

Miñano Pérez, Pablo; Castejón Costa, Juan-Luis; Gilar Corbí, Raquel

2012-03-01

As a result of studies examining factors involved in the learning process, various structural models have been developed to explain the direct and indirect effects that occur between the variables in these models. The objective was to evaluate a structural model of cognitive and motivational variables predicting academic achievement, including general intelligence, academic self-concept, goal orientations, effort and learning strategies. The sample comprised of 341 Spanish students in the first year of compulsory secondary education. Different tests and questionnaires were used to evaluate each variable, and Structural Equation Modelling (SEM) was applied to contrast the relationships of the initial model. The model proposed had a satisfactory fit, and all the hypothesised relationships were significant. General intelligence was the variable most able to explain academic achievement. Also important was the direct influence of academic self-concept on achievement, goal orientations and effort, as well as the mediating ability of effort and learning strategies between academic goals and final achievement.

Using Equation-Free Computation to Accelerate Network-Free Stochastic Simulation of Chemical Kinetics.

PubMed

Lin, Yen Ting; Chylek, Lily A; Lemons, Nathan W; Hlavacek, William S

2018-06-21

The chemical kinetics of many complex systems can be concisely represented by reaction rules, which can be used to generate reaction events via a kinetic Monte Carlo method that has been termed network-free simulation. Here, we demonstrate accelerated network-free simulation through a novel approach to equation-free computation. In this process, variables are introduced that approximately capture system state. Derivatives of these variables are estimated using short bursts of exact stochastic simulation and finite differencing. The variables are then projected forward in time via a numerical integration scheme, after which a new exact stochastic simulation is initialized and the whole process repeats. The projection step increases efficiency by bypassing the firing of numerous individual reaction events. As we show, the projected variables may be defined as populations of building blocks of chemical species. The maximal number of connected molecules included in these building blocks determines the degree of approximation. Equation-free acceleration of network-free simulation is found to be both accurate and efficient.

Software sensors for biomass concentration in a SSC process using artificial neural networks and support vector machine.

PubMed

Acuña, Gonzalo; Ramirez, Cristian; Curilem, Millaray

2014-01-01

The lack of sensors for some relevant state variables in fermentation processes can be coped by developing appropriate software sensors. In this work, NARX-ANN, NARMAX-ANN, NARX-SVM and NARMAX-SVM models are compared when acting as software sensors of biomass concentration for a solid substrate cultivation (SSC) process. Results show that NARMAX-SVM outperforms the other models with an SMAPE index under 9 for a 20 % amplitude noise. In addition, NARMAX models perform better than NARX models under the same noise conditions because of their better predictive capabilities as they include prediction errors as inputs. In the case of perturbation of initial conditions of the autoregressive variable, NARX models exhibited better convergence capabilities. This work also confirms that a difficult to measure variable, like biomass concentration, can be estimated on-line from easy to measure variables like CO₂ and O₂ using an adequate software sensor based on computational intelligence techniques.

Organizational factors associated with readiness for change in residential aged care settings.

PubMed

von Treuer, Kathryn; Karantzas, Gery; McCabe, Marita; Mellor, David; Konis, Anastasia; Davison, Tanya E; O'Connor, Daniel

2018-02-01

Organizational change is inevitable in any workplace. Previous research has shown that leadership and a number of organizational climate and contextual variables can affect the adoption of change initiatives. The effect of these workplace variables is particularly important in stressful work sectors such as aged care where employees work with challenging older clients who frequently exhibit dementia and depression. This study sought to examine the effect of organizational climate and leadership variables on organizational readiness for change across 21 residential aged care facilities. Staff from each facility (N = 255) completed a self-report measure assessing organizational factors including organizational climate, leadership and readiness for change. A hierarchical regression model revealed that the organizational climate variables of work pressure, innovation, and transformational leadership were predictive of employee perceptions of organizational readiness for change. These findings suggest that within aged care facilities an organization's capacity to change their organizational climate and leadership practices may enhance an organization's readiness for change.

Distillation of mixed-state continuous-variable entanglement by photon subtraction

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

Zhang Shengli; Loock, Peter van

2010-12-15

We present a detailed theoretical analysis for the distillation of one copy of a mixed two-mode continuous-variable entangled state using beam splitters and coherent photon-detection techniques, including conventional on-off detectors and photon-number-resolving detectors. The initial Gaussian mixed-entangled states are generated by transmitting a two-mode squeezed state through a lossy bosonic channel, corresponding to the primary source of errors in current approaches to optical quantum communication. We provide explicit formulas to calculate the entanglement in terms of logarithmic negativity before and after distillation, including losses in the channel and the photon detection, and show that one-copy distillation is still possible evenmore » for losses near the typical fiber channel attenuation length. A lower bound for the transmission coefficient of the photon-subtraction beam splitter is derived, representing the minimal value that still allows to enhance the entanglement.« less

Space Shuttle 2 advanced space transportation system, volume 2

NASA Technical Reports Server (NTRS)

Adinaro, James N.; Benefield, Philip A.; Johnson, Shelby D.; Knight, Lisa K.

1989-01-01

To determine the best configuration from all candidate configurations, it was necessary first to calculate minimum system weights and performance. To optimize the design, it is necessary to vary configuration-specific variables such as total system weight, thrust-to-weight ratios, burn durations, total thrust available, and mass fraction for the system. Optimizing each of these variables at the same time is technically unfeasible and not necessarily mathematically possible. However, discrete sets of data can be generated which will eliminate many candidate configurations. From the most promising remaining designs, a final configuration can be selected. Included are the three most important designs considered: one which closely approximates the design criteria set forth in a Marshall Space Flight Center study of the Shuttle 2; the configuration used in the initial proposal; and the final configuration. A listing by cell of the formulas used to generate the aforementioned data is included for reference.

Instrumental record of debris flow initiation during natural rainfall: Implications for modeling slope stability

USGS Publications Warehouse

Montgomery, D.R.; Schmidt, K.M.; Dietrich, W.E.; McKean, J.

2009-01-01

The middle of a hillslope hollow in the Oregon Coast Range failed and mobilized as a debris flow during heavy rainfall in November 1996. Automated pressure transducers recorded high spatial variability of pore water pressure within the area that mobilized as a debris flow, which initiated where local upward flow from bedrock developed into overlying colluvium. Postfailure observations of the bedrock surface exposed in the debris flow scar reveal a strong spatial correspondence between elevated piezometric response and water discharging from bedrock fractures. Measurements of apparent root cohesion on the basal (Cb) and lateral (Cl) scarp demonstrate substantial local variability, with areally weighted values of Cb = 0.1 and Cl = 4.6 kPa. Using measured soil properties and basal root strength, the widely used infinite slope model, employed assuming slope parallel groundwater flow, provides a poor prediction of hydrologie conditions at failure. In contrast, a model including lateral root strength (but neglecting lateral frictional strength) gave a predicted critical value of relative soil saturation that fell within the range defined by the arithmetic and geometric mean values at the time of failure. The 3-D slope stability model CLARA-W, used with locally observed pore water pressure, predicted small areas with lower factors of safety within the overall slide mass at sites consistent with field observations of where the failure initiated. This highly variable and localized nature of small areas of high pore pressure that can trigger slope failure means, however, that substantial uncertainty appears inevitable for estimating hydrologie conditions within incipient debris flows under natural conditions. Copyright 2009 by the American Geophysical Union.

Contracts, grants and funding summary of supersonic cruise research and variable-cycle engine technology programs, 1972 - 1982

NASA Technical Reports Server (NTRS)

Hoffman, S.; Varholic, M. C.

1983-01-01

NASA-SCAR (AST) program was initiated in 1972 at the direct request of the Executive Office of the White House and Congress following termination of the U.S. SST program. The purpose of SCR was to conduct a focused research and technology program on those technology programs which contributed to the SST termination and, also, to provide an expanded data base for future civil and military supersonic transport aircraft. Funding for the Supersonic Cruise Research (SCR) Program was initiated in fiscal year 1973 and terminated in fiscal year 1981. The program was implemented through contracts and grants with industry, universities, and by in-house investigations at the NASA/OAST centers. The studies included system studies and five disciplines: propulsion, stratospheric emissions impact, materials and structures, aerodynamic performance, and stability and control. The NASA/Lewis Variable-Cycle Engine (VCE) Component Program was initiated in 1976 to augment the SCR program in the area of propulsion. After about 2 years, the title was changed to VCE Technology program. The total number of contractors and grantees on record at the AST office in 1982 was 101 for SCR and 4 for VCE. This paper presents a compilation of all the contracts and grants as well as the funding summaries for both programs.

Dry and wet arc track propagation resistance testing

NASA Technical Reports Server (NTRS)

Beach, Rex

1995-01-01

The wet arc-propagation resistance test for wire insulation provides an assessment of the ability of an insulation to prevent damage in an electrical environment. Results of an arc-propagation test may vary slightly due to the method of arc initiation; therefore a standard test method must be selected to evaluate the general arc-propagation resistance characteristics of an insulation. This test method initiates an arc by dripping salt water over pre-damaged wires which creates a conductive path between the wires. The power supply, test current, circuit resistances, and other variables are optimized for testing 20 guage wires. The use of other wire sizes may require modifications to the test variables. The dry arc-propagation resistance test for wire insulation also provides an assessment of the ability of an insulation to prevent damage in an electrical arc environment. In service, electrical arcs may originate form a variety of factors including insulation deterioration, faulty installation, and chafing. Here too, a standard test method must be selected to evaluate the general arc-propagation resistance characteristics of an insulation. This test method initiates an arc with a vibrating blade. The test also evaluates the ability of the insulation to prevent further arc-propagation when the electrical arc is re-energized.

Aging and death-associated changes in serum albumin variability over the course of chronic hemodialysis treatment.

PubMed

Nakazato, Yuichi; Kurane, Riichi; Hirose, Satoru; Watanabe, Akihisa; Shimoyama, Hiromi

2017-01-01

Several epidemiological studies have demonstrated associations between variability in a number of biological parameters and adverse outcomes. As the variability may reflect impaired homeostatic regulation, we assessed albumin variability over time in chronic hemodialysis (HD) patients. Data from 1346 subjects who received chronic HD treatment from May 2001 to February 2015 were analyzed according to three phases of HD treatment: post-HD initiation, during maintenance HD treatment, and before death. The serum albumin values were grouped according to the time interval from HD initiation or death, and the yearly trends for both the albumin levels and the intra-individual albumin variability (quantified by the residual coefficient of variation: Alb-rCV) were examined. The HD initiation and death-associated changes were also analyzed using generalized additive mixed models. Furthermore, the long-term trend throughout the maintenance treatment period was evaluated separately using linear regression models. Albumin levels and variability showed distinctive changes during each of the 3 periods. After HD initiation, albumin variability decreased and reached a nadir within a year. During the subsequent maintenance treatment period (interquartile range = 5.2-11.0 years), the log Alb-rCV showed a significant upward trend (mean slope: 0.011 ± 0.035 /year), and its overall mean was -1.49 ± 0.08 (equivalent to an Alb-rCV of 3.22%). During the 1-2 years before death, this upward trend clearly accelerated, and the mean log Alb-rCV in the last year of life was -1.36 ± 0.17. The albumin levels and variability were negatively correlated with each other and exhibited exactly opposite movements throughout the course of chronic HD treatment. Different from the albumin levels, albumin variability was not dependent on chronological age but was independently associated with an individual's aging and death process. The observed upward trend in albumin variability seems to be consistent with a presumed aging-related decline in homeostatic capacity.

From the Last Interglacial to the Anthropocene: Modelling a Complete Glacial Cycle (PalMod)

NASA Astrophysics Data System (ADS)

Brücher, Tim; Latif, Mojib

2017-04-01

We will give a short overview and update on the current status of the national climate modelling initiative PalMod (Paleo Modelling, www.palmod.de). PalMod focuses on the understanding of the climate system dynamics and its variability during the last glacial cycle. The initiative is funded by the German Federal Ministry of Education and Research (BMBF) and its specific topics are: (i) to identify and quantify the relative contributions of the fundamental processes which determined the Earth's climate trajectory and variability during the last glacial cycle, (ii) to simulate with comprehensive Earth System Models (ESMs) the climate from the peak of the last interglacial - the Eemian warm period - up to the present, including the changes in the spectrum of variability, and (iii) to assess possible future climate trajectories beyond this century during the next millennia with sophisticated ESMs tested in such a way. The research is intended to be conducted over a period of 10 years, but with shorter funding cycles. PalMod kicked off in February 2016. The first phase focuses on the last deglaciation (app. the last 23.000 years). From the ESM perspective PalMod pushes forward model development by coupling ESM with dynamical ice sheet models. Computer scientists work on speeding up climate models using different concepts (like parallelisation in time) and one working group is dedicated to perform a comprehensive data synthesis to validate model performance. The envisioned approach is innovative in three respects. First, the consortium aims at simulating a full glacial cycle in transient mode and with comprehensive ESMs which allow full interactions between the physical and biogeochemical components of the Earth system, including ice sheets. Second, we shall address climate variability during the last glacial cycle on a large range of time scales, from interannual to multi-millennial, and attempt to quantify the relative contributions of external forcing and processes internal to the Earth system to climate variability at different time scales. Third, in order to achieve a higher level of understanding of natural climate variability at time scales of millennia, its governing processes and implications for the future climate, we bring together three different research communities: the Earth system modeling community, the proxy data community and the computational science community. The consortium consists of 18 partners including all major modelling centers within Germany. The funding comprises approximately 65 PostDoc positions and more than 120 scientists are involved. PalMod is coordinated at the Helmholtz Centre for Ocean Research Kiel (GEOMAR).

Reproducibility of Interferon Gamma (IFN-γ) Release Assays. A Systematic Review

PubMed Central

Tagmouti, Saloua; Slater, Madeline; Benedetti, Andrea; Kik, Sandra V.; Banaei, Niaz; Cattamanchi, Adithya; Metcalfe, John; Dowdy, David; van Zyl Smit, Richard; Dendukuri, Nandini

2014-01-01

Rationale: Interferon gamma (IFN-γ) release assays for latent tuberculosis infection result in a larger-than-expected number of conversions and reversions in occupational screening programs, and reproducibility of test results is a concern. Objectives: Knowledge of the relative contribution and extent of the individual sources of variability (immunological, preanalytical, or analytical) could help optimize testing protocols. Methods: We performed a systematic review of studies published by October 2013 on all potential sources of variability of commercial IFN-γ release assays (QuantiFERON-TB Gold In-Tube and T-SPOT.TB). The included studies assessed test variability under identical conditions and under different conditions (the latter both overall and stratified by individual sources of variability). Linear mixed effects models were used to estimate within-subject SD. Measurements and Main Results: We identified a total of 26 articles, including 7 studies analyzing variability under the same conditions, 10 studies analyzing variability with repeat testing over time under different conditions, and 19 studies reporting individual sources of variability. Most data were on QuantiFERON (only three studies on T-SPOT.TB). A considerable number of conversions and reversions were seen around the manufacturer-recommended cut-point. The estimated range of variability of IFN-γ response in QuantiFERON under identical conditions was ±0.47 IU/ml (coefficient of variation, 13%) and ±0.26 IU/ml (30%) for individuals with an initial IFN-γ response in the borderline range (0.25–0.80 IU/ml). The estimated range of variability in noncontrolled settings was substantially larger (±1.4 IU/ml; 60%). Blood volume inoculated into QuantiFERON tubes and preanalytic delay were identified as key sources of variability. Conclusions: This systematic review shows substantial variability with repeat IFN-γ release assays testing even under identical conditions, suggesting that reversions and conversions around the existing cut-point should be interpreted with caution. PMID:25188809

Correlates of Sexual Satisfaction Among Sexually Active Postmenopausal Women in the Women’s Health Initiative-Observational Study

PubMed Central

Jaramillo, Sarah A.; Legault, Claudine; Freund, Karen M.; Cochrane, Barbara B.; Manson, JoAnn E.; Wenger, Nanette K.; Eaton, Charles B.; Rodriguez, Beatriz L.; McNeeley, S. Gene; Bonds, Denise

2008-01-01

BACKGROUND Satisfaction with sexual activity is important for health-related quality of life, but little is known about the sexual health of postmenopausal women. OBJECTIVE Describe factors associated with sexual satisfaction among sexually active postmenopausal women. DESIGN Cross-sectional analysis. PARTICIPANTS All members of the Women’s Health Initiative-Observational Study (WHI-OS), ages 50–79, excluding women who did not respond to the sexual satisfaction question or reported no partnered sexual activity in the past year (N = 46,525). MEASUREMENTS Primary outcome: dichotomous response to the question, “How satisfied are you with your sexual activity (satisfied versus unsatisfied)?” Covariates included sociodemographic factors, measures of physical and mental health, and gynecological variables, medications, and health behaviors related to female sexual health. RESULTS Of the cohort, 52% reported sexual activity with a partner in the past year, and 96% of these answered the sexual satisfaction question. Nonmodifiable factors associated with sexual dissatisfaction included age, identification with certain racial or ethnic groups, marital status, parity, and smoking history. Potentially modifiable factors included lower mental health status and use of SSRIs. The final model yielded a c-statistic of 0.613, reflecting only a modest ability to discriminate between the sexually satisfied and dissatisfied. CONCLUSIONS Among postmenopausal women, the variables selected for examination yielded modest ability to discriminate between sexually satisfied and dissatisfied participants. Further study is necessary to better describe the cofactors associated with sexual satisfaction in postmenopausal women. PMID:18839256

Decadal evaluation of regional climate, air quality, and their interactions over the continental US and their interactions using WRF/Chem version 3.6.1

NASA Astrophysics Data System (ADS)

Yahya, Khairunnisa; Wang, Kai; Campbell, Patrick; Glotfelty, Timothy; He, Jian; Zhang, Yang

2016-02-01

The Weather Research and Forecasting model with Chemistry (WRF/Chem) v3.6.1 with the Carbon Bond 2005 (CB05) gas-phase mechanism is evaluated for its first decadal application during 2001-2010 using the Representative Concentration Pathway 8.5 (RCP 8.5) emissions to assess its capability and appropriateness for long-term climatological simulations. The initial and boundary conditions are downscaled from the modified Community Earth System Model/Community Atmosphere Model (CESM/CAM5) v1.2.2. The meteorological initial and boundary conditions are bias-corrected using the National Center for Environmental Protection's Final (FNL) Operational Global Analysis data. Climatological evaluations are carried out for meteorological, chemical, and aerosol-cloud-radiation variables against data from surface networks and satellite retrievals. The model performs very well for the 2 m temperature (T2) for the 10-year period, with only a small cold bias of -0.3 °C. Biases in other meteorological variables including relative humidity at 2 m, wind speed at 10 m, and precipitation tend to be site- and season-specific; however, with the exception of T2, consistent annual biases exist for most of the years from 2001 to 2010. Ozone mixing ratios are slightly overpredicted at both urban and rural locations with a normalized mean bias (NMB) of 9.7 % but underpredicted at rural locations with an NMB of -8.8 %. PM2.5 concentrations are moderately overpredicted with an NMB of 23.3 % at rural sites but slightly underpredicted with an NMB of -10.8 % at urban/suburban sites. In general, the model performs relatively well for chemical and meteorological variables, and not as well for aerosol-cloud-radiation variables. Cloud-aerosol variables including aerosol optical depth, cloud water path, cloud optical thickness, and cloud droplet number concentration are generally underpredicted on average across the continental US. Overpredictions of several cloud variables over the eastern US result in underpredictions of radiation variables (such as net shortwave radiation - GSW - with a mean bias - MB - of -5.7 W m-2) and overpredictions of shortwave and longwave cloud forcing (MBs of ˜ 7 to 8 W m-2), which are important climate variables. While the current performance is deemed to be acceptable, improvements to the bias-correction method for CESM downscaling and the model parameterizations of cloud dynamics and thermodynamics, as well as aerosol-cloud interactions, can potentially improve model performance for long-term climate simulations.

What factors have influence on persistence of neck pain after a whiplash?

PubMed

Cobo, Eulogio Pleguezuelos; Mesquida, M Engracia Pérez; Fanegas, Elisabet Palomera; Atanasio, Eva Moreno; Pastor, M Beatriz Samitier; Pont, Cristina Perucho; Prieto, Carlos Matarrubia; Gómez, Genoveva Reverón; Cano, Lluis Guirao

2010-04-20

Prospective longitudinal study. To identify prognosis factors that allow us to identify patients with risk of developing chronic symptoms and disabilities after a whiplash injury. The prognosis factors for poor recovery in acute whiplash are not conclusive. We included 557 patients who suffered whiplash injury after road traffic accident and visited the Department of Physical Medicine and Rehabilitation of Mataró Hospital (Spain) for medical evaluation and rehabilitation treatment. The variables were collected following a protocol designed for the study, and all patients were assessed through the Visual Analogue Scale (VAS) for the intensity of neck pain, the Goldberg Depression and Anxiety Scale and the Northwick Park Neck Pain Questionnaire (NPH) for cervical column functionality at initial evaluation and 6 months later. Factors related with VAS 6 months after the whiplash injury were women, age, number of days of cervical column immobilization, previous neck pain, self-employed workers, housewives, pensioners, students, presence of headache or dizziness, and VAS, Goldberg Depression and Anxiety scale, and NPH scores at initial evaluation. In multivaried analysis, it had been found that the variables that had influence on VAS 6 months after the whiplash injury were statistically significant for age, presence of dizziness, self-employed workers, and VAS and NPH scores at initial evaluation. Our findings indicate that factors that allow us to identify patients at risk for poor recovery are age, dizziness, and initial evaluation of neck pain with VAS and cervical column functionality with NPH.

Five-city economics of a solar hot-water-system

NASA Technical Reports Server (NTRS)

1981-01-01

Report projects energy savings and system costs for five sites using analysis of actual solar energy installation performance in Togus, Maine. Maine system supplies 75 percent of hot water needed for single-family residence; economic payback period is 19 years. Benefits for all sites depend on maintenance or decrease of initial investment required and continuing increase in cost of conventional energy. Report includes analysis weighing potential changes in variables used to evaluate system profitability.

Variable Dynamic Testbed Vehicle Dynamics Analysis

DOT National Transportation Integrated Search

1996-03-01

ANTI-ROLL BAR, EMULATION, FOUR-WHEEL-STEERING, LATERAL RESPONSE CHARACTERISTICS, SIMULATION, VARIABLE DYNAMIC TESTBED VEHICLE, INTELLIGENT VEHICLE INITIATIVE OR IVI : THE VARIABLE DYNAMIC TESTBED VEHICLE (VDTV) CONCEPT HAS BEEN PROPOSED AS A TOOL...

Using a cross section to train veterinary students to visualize anatomical structures in three dimensions

NASA Astrophysics Data System (ADS)

Provo, Judy; Lamar, Carlton; Newby, Timothy

2002-01-01

A cross section was used to enhance three-dimensional knowledge of anatomy of the canine head. All veterinary students in two successive classes (n = 124) dissected the head; experimental groups also identified structures on a cross section of the head. A test assessing spatial knowledge of the head generated 10 dependent variables from two administrations. The test had content validity and statistically significant interrater and test-retest reliability. A live-dog examination generated one additional dependent variable. Analysis of covariance controlling for performance on course examinations and quizzes revealed no treatment effect. Including spatial skill as a third covariate revealed a statistically significant effect of spatial skill on three dependent variables. Men initially had greater spatial skill than women, but spatial skills were equal after 8 months. A qualitative analysis showed the positive impact of this experience on participants. Suggestions for improvement and future research are discussed.

A probabilistic fatigue analysis of multiple site damage

NASA Technical Reports Server (NTRS)

Rohrbaugh, S. M.; Ruff, D.; Hillberry, B. M.; Mccabe, G.; Grandt, A. F., Jr.

1994-01-01

The variability in initial crack size and fatigue crack growth is incorporated in a probabilistic model that is used to predict the fatigue lives for unstiffened aluminum alloy panels containing multiple site damage (MSD). The uncertainty of the damage in the MSD panel is represented by a distribution of fatigue crack lengths that are analytically derived from equivalent initial flaw sizes. The variability in fatigue crack growth rate is characterized by stochastic descriptions of crack growth parameters for a modified Paris crack growth law. A Monte-Carlo simulation explicitly describes the MSD panel by randomly selecting values from the stochastic variables and then grows the MSD cracks with a deterministic fatigue model until the panel fails. Different simulations investigate the influences of the fatigue variability on the distributions of remaining fatigue lives. Six cases that consider fixed and variable conditions of initial crack size and fatigue crack growth rate are examined. The crack size distribution exhibited a dominant effect on the remaining fatigue life distribution, and the variable crack growth rate exhibited a lesser effect on the distribution. In addition, the probabilistic model predicted that only a small percentage of the life remains after a lead crack develops in the MSD panel.

Child Attitude Toward Illness Scale (CATIS): A systematic review of the literature.

PubMed

Ramsey, Rachelle R; Ryan, Jamie L; Fedele, David A; Mullins, Larry L; Chaney, John M; Wagner, Janelle L

2016-06-01

The objective of this study was to systematically review the literature utilizing the Child Attitude Toward Illness Scale (CATIS) as a measure of illness attitudes within pediatric chronic illness, including epilepsy, and provide recommendations for its use. This review includes an examination of the psychometric properties of the CATIS and the relationship between the CATIS and psychological, academic, behavioral, and illness variables. Electronic searches were conducted using Medline and PsychINFO to identify twenty-two relevant publications. The CATIS was identified as a reliable and valid self-report assessment tool across chronic illnesses, including pediatric epilepsy. Although originally developed for children ages 8-12, the CATIS has demonstrated reliability and validity in youth ages 8-22. The CATIS scores were reliably associated with cognitive appraisal variables and internalizing symptoms. Initial support exists for the relation between illness attitudes and externalizing behavior, academic functioning, and psychosocial care needs. Mixed findings were reported with regard to the relation between illness attitudes and demographic and disease variables, as well as both social and family functioning. The CATIS is a psychometrically sound self-report instrument for measuring illness attitudes and demonstrates clinical utility for examining adjustment outcomes across chronic illnesses, particularly pediatric epilepsy. Copyright © 2016 Elsevier Inc. All rights reserved.

A US database study characterizing patients initiating a budesonide-formoterol combination versus tiotropium bromide as initial maintenance therapy for chronic obstructive pulmonary disease.

PubMed

Kern, David M; Williams, Setareh A; Tunceli, Ozgur; Wessman, Catrin; Zhou, Siting; Pethick, Ned; Elhefni, Hanaa; Trudo, Frank

2014-01-01

To compare clinical and demographic characteristics, resource utilization and costs of chronic obstructive pulmonary disease (COPD) patients prior to initiating budesonide-formoterol combination (BFC) or tiotropium-maintenance therapy. This cross-sectional study used claims-based diagnosis to identify COPD patients in the HealthCore Integrated Research Database who initiated BFC or tiotropium therapy between March 1, 2009 and January 31, 2012 (intake period); the index date was defined as the initial prescription fill for either agent. Patients diagnosed with respiratory tract cancer or receiving inhaled corticosteroids/long-acting β2-adrenergic agonists or tiotropium in 12 months prior to index date were excluded. Categorical variables were evaluated with χ(2) tests; mean cost differences were evaluated using γ-regression. Overall, 6,940 BFC and 10,831 tiotropium patients were identified. The BFC group was younger (mean age 64 versus 67 years), with a greater proportion of females (54% versus 51%). BFC-treated patients had more comorbid respiratory conditions, including asthma (25% versus 13%), but fewer comorbid cardiovascular conditions, including atherosclerosis (7% versus 10%) and myocardial infarction (4% versus 6%). A greater proportion of BFC patients received prior respiratory medication, including oral corticosteroids (46% versus 35%) and short-acting β2-agonists (44% versus 35%). Tiotropium-treated patients had a greater mean number of COPD-related outpatient visits (4.6 versus 4.1). BFC-treated patients had lower total all-cause ($17,259 versus $17,926) and COPD-related ($1,718 versus $1,930) health care costs, driven by lower all-cause and COPD-related inpatient expenditures. Initiators of BFC or tiotropium showed differences in clinical and demographic characteristics and health care utilization and costs prior to starting COPD maintenance therapy.

Retrospective Analysis of Dose Titration and Serum Testosterone Level Assessments in Patients Treated With Topical Testosterone.

PubMed

Muram, David; Kaltenboeck, Anna; Boytsov, Natalie; Hayes-Larson, Eleanor; Ivanova, Jasmina; Birnbaum, Howard G; Swindle, Ralph

2015-11-01

Patterns of care following topical testosterone agent (TTA) initiation are poorly understood. This study aimed to characterize care following TTA initiation and compare results between patients with and without a serum testosterone (T) assay within 30 days before and including TTA initiation. Adult men (N=4,146) initiating TTAs from January 1, 2011, to March 31, 2012, were identified from a commercially insured database. Patients were included if they initiated at recommended starting dose (RSD) and had ≥12 and ≥6 months of continuous eligibility preinitiation (baseline) and postinitiation (study period), respectively. Patients were stratified by preinitiation T assay. Maintenance dose attainment month was determined using unadjusted generalized estimating equations regression to compare dose relative to RSD month by month. Outcomes included maintenance dose attainment month, time to stopping of index TTA refills or a claim for nonindex testosterone replacement therapy (TRT), and proportion of patients with study period T assay or diagnosis of hypogonadism (HG) or another low testosterone condition, and were compared using chi-square and Wilcoxon rank-sum tests for categorical and continuous variables, respectively. Maintenance dose was attained in Month 4 postinitiation, at 115.2% of RSD. Approximately 46% of patients had a preinitiation T assay; these men were more likely to receive a diagnosis of HG or another low testosterone condition, to have a follow-up T assay, to continue treatment by filling a nonindex TRT, and less likely to stop refilling treatment with their index TTA. Differences in care following TTA initiation suggest that preinitiation T assays (i.e., guideline-based care) may be helpful in ensuring treatment benefits. © The Author(s) 2014.

Governance of extended lifecycle in large-scale eHealth initiatives: analyzing variability of enterprise architecture elements.

PubMed

Mykkänen, Juha; Virkanen, Hannu; Tuomainen, Mika

2013-01-01

The governance of large eHealth initiatives requires traceability of many requirements and design decisions. We provide a model which we use to conceptually analyze variability of several enterprise architecture (EA) elements throughout the extended lifecycle of development goals using interrelated projects related to the national ePrescription in Finland.

Continuous glucose monitoring to assess the ecologic validity of dietary glycemic index and glycemic load123

PubMed Central

Ebbeling, Cara B; Wadden, Thomas A; Ludwig, David S

2011-01-01

Background: The circumstances under which the glycemic index (GI) and glycemic load (GL) are derived do not reflect real-world eating behavior. Thus, the ecologic validity of these constructs is incompletely known. Objective: This study examined the relation of dietary intake to glycemic response when foods are consumed under free-living conditions. Design: Participants were 26 overweight or obese adults with type 2 diabetes who participated in a randomized trial of lifestyle modification. The current study includes baseline data, before initiation of the intervention. Participants wore a continuous glucose monitor and simultaneously kept a food diary for 3 d. The dietary variables included GI, GL, and intakes of energy, fat, protein, carbohydrate, sugars, and fiber. The glycemic response variables included AUC, mean and SD of continuous glucose monitoring (CGM) values, percentage of CGM values in euglycemic and hyperglycemic ranges, and mean amplitude of glycemic excursions. Relations between daily dietary intake and glycemic outcomes were examined. Results: Data were available from 41 d of monitoring. Partial correlations, controlled for energy intake, indicated that GI or GL was significantly associated with each glycemic response outcome. In multivariate analyses, dietary GI accounted for 10% to 18% of the variance in each glycemic variable, independent of energy and carbohydrate intakes (P < 0.01). Conclusions: The data support the ecologic validity of the GI and GL constructs in free-living obese adults with type 2 diabetes. GI was the strongest and most consistent independent predictor of glycemic stability and variability. PMID:22071699

A Potential Function Derivation of a Constitutive Equation for Inelastic Material Response

NASA Technical Reports Server (NTRS)

Stouffer, D. C.; Elfoutouh, N. A.

1983-01-01

Physical and thermodynamic concepts are used to develop a potential function for application to high temperature polycrystalline material response. Inherent in the formulation is a differential relationship between the potential function and constitutive equation in terms of the state variables. Integration of the differential relationship produces a state variable evolution equation that requires specification of the initial value of the state variable and its time derivative. It is shown that the initial loading rate, which is directly related to the initial hardening rate, can significantly influence subsequent material response. This effect is consistent with observed material behavior on the macroscopic and microscopic levels, and may explain the wide scatter in response often found in creep testing.

Engaging Generation Now, Inspiring Generation Next

NASA Astrophysics Data System (ADS)

Simonsen, Mike; Gay, P.

2008-05-01

In 2008, the Education and Public Outreach Committee of the American Association of Variable Star Observers (AAVSO) initiated several new strategies for disseminating accurate, stimulating, engaging information on general astronomy and variable star science to thousands of students, parents, and amateur astronomers each year through astronomy clubs, societies, and star party events. We are initiating contact with astronomy clubs and organizations to offer qualified speakers from the AAVSO Speakers Bureau for their meetings and activities. The current roster of speakers include, professional astronomers, doctors, engineers, teachers and some of the world's leading variable star observers. Request information is available on the AAVSO website. For organizations and individuals unable to engage one of our speakers due to time, distance or financial constraints, we have made PowerPoint presentations used in previous talks available free for download from the same web pages. Thousands of amateur astronomers and their children attend star parties each year. As an extension of our speakers’ bureau, our goal is to have an AAVSO representative at each of the major star parties each year giving an enthusiastic talk on variable stars or related astronomical subject and supplying inspirational printed materials on astronomy and amateur contributions to science. The nation's largest astronomy clubs have monthly newsletters they distribute to their membership. Newsletter editors are constantly in need of quality, interesting content to fill out their issues each month. We are offering a `writers’ bureau’ service to newsletter editors, similar to the news wire services used by newspapers. We will supply up to a half dozen articles on astronomy and variable star science each month for editors to use at their discretion in their publications. Our goal is to provide information, inspiration and encourage participation among amateur astronomers and their kids, our next generation of astronomers.

Prognostic importance of glycaemic variability on hospital mortality in patients hospitalised in Internal Medicine Departments.

PubMed

Sáenz-Abad, D; Gimeno-Orna, J A; Pérez-Calvo, J I

2015-12-01

The objective was to assess the prognostic importance of various glycaemic control measures on hospital mortality. Retrospective, analytical cohort study that included patients hospitalised in internal medicine departments with a diagnosis related to diabetes mellitus (DM), excluding acute decompensations. The clinical endpoint was hospital mortality. We recorded clinical, analytical and glycaemic control-related variables (scheduled insulin administration, plasma glycaemia at admission, HbA1c, mean glycaemia (MG) and in-hospital glycaemic variability and hypoglycaemia). The measurement of hospital mortality predictors was performed using univariate and multivariate logistic regression. A total of 384 patients (50.3% men) were included. The mean age was 78.5 (SD, 10.3) years. The DM-related diagnoses were type 2 diabetes (83.6%) and stress hyperglycaemia (6.8%). Thirty-one (8.1%) patients died while in hospital. In the multivariate analysis, the best model for predicting mortality (R(2)=0.326; P<.0001) consisted, in order of importance, of age (χ(2)=8.19; OR=1.094; 95% CI 1.020-1.174; P=.004), Charlson index (χ(2)=7.28; OR=1.48; 95% CI 1.11-1.99; P=.007), initial glycaemia (χ(2)=6.05; OR=1.007; 95% CI 1.001-1.014; P=.014), HbA1c (χ(2)=5.76; OR=0.59; 95% CI 0.33-1; P=.016), glycaemic variability (χ(2)=4.41; OR=1.031; 95% CI 1-1.062; P=.036), need for corticosteroid treatment (χ(2)=4.03; OR=3.1; 95% CI 1-9.64; P=.045), administration of scheduled insulin (χ(2)=3.98; OR=0.26; 95% CI 0.066-1; P=.046) and systolic blood pressure (χ(2)=2.92; OR=0.985; 95% CI 0.97-1.003; P=.088). An increase in initial glycaemia and in-hospital glycaemic variability predict the risk of mortality for hospitalised patients with DM. Copyright © 2015 Elsevier España, S.L.U. y Sociedad Española de Medicina Interna (SEMI). All rights reserved.

Assimilation of Dual-Polarimetric Radar Observations with WRF GSI

NASA Technical Reports Server (NTRS)

Li, Xuanli; Mecikalski, John; Fehnel, Traci; Zavodsky, Bradley; Srikishen, Jayanthi

2014-01-01

Dual-polarimetric (dual-pol) radar typically transmits both horizontally and vertically polarized radio wave pulses. From the two different reflected power returns, more accurate estimate of liquid and solid cloud and precipitation can be provided. The upgrade of the traditional NWS WSR-88D radar to include dual-pol capabilities will soon be completed for the entire NEXRAD network. Therefore, the use of dual-pol radar network will have a broad impact in both research and operational communities. The assimilation of dual-pol radar data is especially challenging as few guidelines have been provided by previous research. It is our goal to examine how to best use dual-pol radar data to improve forecast of severe storm and forecast initialization. In recent years, the Development Testbed Center (DTC) has released the community Gridpoint Statistical Interpolation (GSI) DA system for the Weather Research and Forecasting (WRF) model. The community GSI system runs in independently environment, yet works functionally equivalent to operational centers. With collaboration with the NASA Short-term Prediction Research and Transition (SPoRT) Center, this study explores regional assimilation of the dual-pol radar variables from the WSR-88D radars for real case storms. Our presentation will highlight our recent effort on incorporating the horizontal reflectivity (ZH), differential reflectivity (ZDR), specific differential phase (KDP), and radial velocity (VR) data for initializing convective storms, with a significant focus being on an improved representation of hydrometeor fields. In addition, discussion will be provided on the development of enhanced assimilation procedures in the GSI system with respect to dual-pol variables. Beyond the dual-pol variable assimilation procedure developing within a GSI framework, highresolution (=1 km) WRF model simulations and storm scale data assimilation experiments will be examined, emphasizing both model initialization and short-term forecast of precipitation fields and processes. Further details of the methodology of data assimilation, the impact of different dual-pol variables, the influence on precipitation forecast will be presented at the conference.

Porting Inition and Failure to Linked Cheetah

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

Vitello, P; Souers, P C

2007-07-18

Linked CHEETAH is a thermo-chemical code coupled to a 2-D hydrocode. Initially, a quadratic-pressure dependent kinetic rate was used, which worked well in modeling prompt detonation of explosives of large size, but does not work on other aspects of explosive behavior. The variable-pressure Tarantula reactive flow rate model was developed with JWL++ in order to also describe failure and initiation, and we have moved this model into Linked CHEETAH. The model works by turning on only above a pressure threshold, where a slow turn-on creates initiation. At a higher pressure, the rate suddenly leaps to a large value over amore » small pressure range. A slowly failing cylinder will see a rapidly declining rate, which pushes it quickly into failure. At a high pressure, the detonation rate is constant. A sequential validation procedure is used, which includes metal-confined cylinders, rate-sticks, corner-turning, initiation and threshold, gap tests and air gaps. The size (diameter) effect is central to the calibration.« less

Postural adjustment errors during lateral step initiation in older and younger adults

PubMed Central

Sparto, Patrick J.; Fuhrman, Susan I.; Redfern, Mark S.; Perera, Subashan; Jennings, J. Richard; Furman, Joseph M.

2016-01-01

The purpose was to examine age differences and varying levels of step response inhibition on the performance of a voluntary lateral step initiation task. Seventy older adults (70 – 94 y) and twenty younger adults (21 – 58 y) performed visually-cued step initiation conditions based on direction and spatial location of arrows, ranging from a simple choice reaction time task to a perceptual inhibition task that included incongruous cues about which direction to step (e.g. a left pointing arrow appearing on the right side of a monitor). Evidence of postural adjustment errors and step latencies were recorded from vertical ground reaction forces exerted by the stepping leg. Compared with younger adults, older adults demonstrated greater variability in step behavior, generated more postural adjustment errors during conditions requiring inhibition, and had greater step initiation latencies that increased more than younger adults as the inhibition requirements of the condition became greater. Step task performance was related to clinical balance test performance more than executive function task performance. PMID:25595953

Postural adjustment errors during lateral step initiation in older and younger adults

PubMed Central

Sparto, Patrick J.; Fuhrman, Susan I.; Redfern, Mark S.; Perera, Subashan; Jennings, J. Richard; Furman, Joseph M.

2014-01-01

The purpose was to examine age differences and varying levels of step response inhibition on the performance of a voluntary lateral step initiation task. Seventy older adults (70 – 94 y) and twenty younger adults (21 – 58 y) performed visually-cued step initiation conditions based on direction and spatial location of arrows, ranging from a simple choice reaction time task to a perceptual inhibition task that included incongruous cues about which direction to step (e.g. a left pointing arrow appearing on the right side of a monitor). Evidence of postural adjustment errors and step latencies were recorded from vertical ground reaction forces exerted by the stepping leg. Compared with younger adults, older adults demonstrated greater variability in step behavior, generated more postural adjustment errors during conditions requiring inhibition, and had greater step initiation latencies that increased more than younger adults as the inhibition requirements of the condition became greater. Step task performance was related to clinical balance test performance more than executive function task performance. PMID:25183162

A heuristic neural network initialization scheme for modeling nonlinear functions in engineering mechanics: continuous development

NASA Astrophysics Data System (ADS)

Pei, Jin-Song; Mai, Eric C.

2007-04-01

This paper introduces a continuous effort towards the development of a heuristic initialization methodology for constructing multilayer feedforward neural networks to model nonlinear functions. In this and previous studies that this work is built upon, including the one presented at SPIE 2006, the authors do not presume to provide a universal method to approximate arbitrary functions, rather the focus is given to the development of a rational and unambiguous initialization procedure that applies to the approximation of nonlinear functions in the specific domain of engineering mechanics. The applications of this exploratory work can be numerous including those associated with potential correlation and interpretation of the inner workings of neural networks, such as damage detection. The goal of this study is fulfilled by utilizing the governing physics and mathematics of nonlinear functions and the strength of the sigmoidal basis function. A step-by-step graphical procedure utilizing a few neural network prototypes as "templates" to approximate commonly seen memoryless nonlinear functions of one or two variables is further developed in this study. Decomposition of complex nonlinear functions into a summation of some simpler nonlinear functions is utilized to exploit this prototype-based initialization methodology. Training examples are presented to demonstrate the rationality and effciency of the proposed methodology when compared with the popular Nguyen-Widrow initialization algorithm. Future work is also identfied.

Universal Surface-initiated Polymerization of Antifouling Zwitterionic Brushes Using A Mussel-Mimetic Peptide Initiator

PubMed Central

Kuang, Jinghao; Messersmith, Phillip B.

2012-01-01

We report a universal method for the surface-initated polymerization (SIP) of a antifouling polymer brush on various classes of surfaces, including noble metals, metal oxides and inert polymers. Inspired by the versatility of mussel adhesive proteins, we synthesized a novel bifunctional tripeptide bromide (BrYKY) which combines an atom transfer radical polymerization (ATRP) initiating alkyl bromide with l-3,4-dihydroxyphenylalanine (DOPA) and lysine. Simple dip-coating of substrates with variable wetting properties and compositions, including Teflon®, in a BrYKY solution at pH 8.5 led to formation of a thin film of cross-linked BrYKY. Subsequently, we showed that the BrYKY layer initiated the ATRP of a zwitterionic monomer, sulfobetaine methacrylate (SBMA) on all substrates, resulting in high density antifouling pSBMA brushes. Both BrYKY deposition and pSBMA grafting were unambiguously confirmed by ellipsometry, X-ray photoelectron spectroscopy and goniometry. All substrates that were coated with BrYKY/pSBMA dramatically reduced bacterial adhesion for 24 h and also resisted mammalian cell adhesion for at least 4 months, demonstrating the long-term stability of the BrYKY anchoring and antifouling properties of pSBMA. The use of BrYKY as a primer and polymerization initiator has the potential to be widely employed in surface grafted polymer brush modifications for biomedical and other applications. PMID:22506651

Effects of ice shelf basal melt variability on evolution of Thwaites Glacier

NASA Astrophysics Data System (ADS)

Hoffman, M. J.; Fyke, J. G.; Price, S. F.; Asay-Davis, X.; Perego, M.

2017-12-01

Theory, modeling, and observations indicate that marine ice sheets on a retrograde bed, including Thwaites Glacier, Antarctica, are only conditionally stable. Previous modeling studies have shown that rapid, unstable retreat can occur when steady ice-shelf basal melting causes the grounding line to retreat past restraining bedrock bumps. Here we explore the initiation and evolution of unstable retreat of Thwaites Glacier when the ice-shelf basal melt forcing includes temporal variability mimicking realistic climate variability. We use the three-dimensional, higher-order Model for Prediction Across Scales-Land Ice (MPASLI) model forced with an ice shelf basal melt parameterization derived from previous coupled ice sheet/ocean simulations. We add sinusoidal temporal variability to the melt parameterization that represents shoaling and deepening of Circumpolar Deep Water. We perform an ensemble of 250 year duration simulations with different values for the amplitude, period, and phase of the variability. Preliminary results suggest that, overall, variability leads to slower grounding line retreat and less mass loss than steady simulations. Short period (2 yr) variability leads to similar results as steady forcing, whereas decadal variability can result in up to one-third less mass loss. Differences in phase lead to a large range in mass loss/grounding line retreat, but it is always less than the steady forcing. The timing of ungrounding from each restraining bedrock bump, which is strongly affected by the melt variability, is the rate limiting factor, and variability-driven delays in ungrounding at each bump accumulate. Grounding line retreat in the regions between bedrock bumps is relatively unaffected by ice shelf melt variability. While the results are sensitive to the form of the melt parameterization and its variability, we conclude that decadal period ice shelf melt variability could potentially delay marine ice sheet instability by up to many decades. However, it does not alter the eventual mass loss and sea level rise at centennial scales. The potential differences are significant enough to highlight the need for further observations to constrain the amplitude and period of the modes of climate and ocean variability relevant to Antarctic ice shelf melting.

Role of subsurface ocean in decadal climate predictability over the South Atlantic.

PubMed

Morioka, Yushi; Doi, Takeshi; Storto, Andrea; Masina, Simona; Behera, Swadhin K

2018-06-04

Decadal climate predictability in the South Atlantic is explored by performing reforecast experiments using a coupled general circulation model with two initialization schemes; one is assimilated with observed sea surface temperature (SST) only, and the other is additionally assimilated with observed subsurface ocean temperature and salinity. The South Atlantic is known to undergo decadal variability exhibiting a meridional dipole of SST anomalies through variations in the subtropical high and ocean heat transport. Decadal reforecast experiments in which only the model SST is initialized with the observation do not predict well the observed decadal SST variability in the South Atlantic, while the other experiments in which the model SST and subsurface ocean are initialized with the observation skillfully predict the observed decadal SST variability, particularly in the Southeast Atlantic. In-depth analysis of upper-ocean heat content reveals that a significant improvement of zonal heat transport in the Southeast Atlantic leads to skillful prediction of decadal SST variability there. These results demonstrate potential roles of subsurface ocean assimilation in the skillful prediction of decadal climate variability over the South Atlantic.

The Routine Fitting of Kinetic Data to Models

PubMed Central

Berman, Mones; Shahn, Ezra; Weiss, Marjory F.

1962-01-01

A mathematical formalism is presented for use with digital computers to permit the routine fitting of data to physical and mathematical models. Given a set of data, the mathematical equations describing a model, initial conditions for an experiment, and initial estimates for the values of model parameters, the computer program automatically proceeds to obtain a least squares fit of the data by an iterative adjustment of the values of the parameters. When the experimental measures are linear combinations of functions, the linear coefficients for a least squares fit may also be calculated. The values of both the parameters of the model and the coefficients for the sum of functions may be unknown independent variables, unknown dependent variables, or known constants. In the case of dependence, only linear dependencies are provided for in routine use. The computer program includes a number of subroutines, each one of which performs a special task. This permits flexibility in choosing various types of solutions and procedures. One subroutine, for example, handles linear differential equations, another, special non-linear functions, etc. The use of analytic or numerical solutions of equations is possible. PMID:13867975

LSENS, The NASA Lewis Kinetics and Sensitivity Analysis Code

NASA Technical Reports Server (NTRS)

Radhakrishnan, K.

2000-01-01

A general chemical kinetics and sensitivity analysis code for complex, homogeneous, gas-phase reactions is described. The main features of the code, LSENS (the NASA Lewis kinetics and sensitivity analysis code), are its flexibility, efficiency and convenience in treating many different chemical reaction models. The models include: static system; steady, one-dimensional, inviscid flow; incident-shock initiated reaction in a shock tube; and a perfectly stirred reactor. In addition, equilibrium computations can be performed for several assigned states. An implicit numerical integration method (LSODE, the Livermore Solver for Ordinary Differential Equations), which works efficiently for the extremes of very fast and very slow reactions, is used to solve the "stiff" ordinary differential equation systems that arise in chemical kinetics. For static reactions, the code uses the decoupled direct method to calculate sensitivity coefficients of the dependent variables and their temporal derivatives with respect to the initial values of dependent variables and/or the rate coefficient parameters. Solution methods for the equilibrium and post-shock conditions and for perfectly stirred reactor problems are either adapted from or based on the procedures built into the NASA code CEA (Chemical Equilibrium and Applications).

Impact of Age at Smoking Initiation on Smoking-Related Morbidity and All-Cause Mortality.

PubMed

Choi, Seung Hee; Stommel, Manfred

2017-07-01

Using a nationally representative sample of U.S. adults, the aims of this study were to examine the impact of early smoking initiation on the development of self-reported smoking-related morbidity and all-cause mortality. National Health Interview Survey data from 1997 through 2005 were linked to the National Death Index with follow-up to December 31, 2011. Two primary dependent variables were smoking-related morbidity and all-cause mortality; the primary independent variable was age of smoking initiation. The analyses included U.S. population of current and former smokers aged ≥30 years (N=90,278; population estimate, 73.4 million). The analysis relied on fitting logistic regression and Cox proportional hazards models. Among the U.S. population of smokers, 7.3% started smoking before age 13 years, 11.0% at ages 13-14 years, 24.2% at ages 15-16 years, 24.5% at ages 17-18 years, 14.5% at ages 19-20 years, and 18.5% at ages ≥21 years. Early smoking initiation before age 13 years was associated with increased risks for cardiovascular/metabolic (OR=1.67) and pulmonary (OR=1.79) diseases as well as smoking-related cancers (OR=2.1) among current smokers; the risks among former smokers were cardiovascular/metabolic (OR=1.38); pulmonary (OR=1.89); and cancers (OR=1.44). Elevated mortality was also related to early smoking initiation among both current (hazard ratio, 1.18) and former smokers (hazard ratio, 1.19). Early smoking initiation increases risks of experiencing smoking-related morbidities and all-cause mortality. These risks are independent of demographic characteristics, SES, health behaviors, and subsequent smoking intensity. Comprehensive tobacco control programs should be implemented to prevent smoking initiation and promote cessation among youth. Copyright © 2017 American Journal of Preventive Medicine. Published by Elsevier Inc. All rights reserved.

The "doses" of initial, untreated hallucinations and delusions: a proof-of-concept study of enhanced predictors of first-episode symptomatology and functioning relative to duration of untreated psychosis.

PubMed

Compton, Michael T; Gordon, Tynessa L; Weiss, Paul S; Walker, Elaine F

2011-11-01

A prominent limitation of literature on duration of untreated psychosis (DUP) is that researchers have studied only unidimensional duration as an early-course predictor, neglecting potential effects of frequency/severity of initial, untreated psychosis. This study demonstrates utility of the concept of "doses" of initial, untreated hallucinations and delusions-representing more complete measures of "exposure"-as enhanced predictors of symptomatology/functioning relative to DUP alone. 109 first-episode patients with a psychotic disorder based on Structured Clinical Interview for DSM-IV Axis I Disorders criteria were assessed at 3 public-sector psychiatric units serving an urban, socially disadvantaged, predominantly African American community between July 2004 and June 2008. Dependent variables included negative symptoms, general psychopathology, insight, and global functioning at initial hospitalization. When added to a baseline model (age, gender, and premorbid academic and social functioning), DUP predicted current negative symptoms (P = .02, model R(2) = 0.20), though dose of hallucinations and dose of delusions did not. However, regarding general psychopathology symptoms, DUP was not predictive, though dose of delusions was, when controlling for the other 5 variables (P = .02, model R(2) = 0.15). DUP was not a significant predictor of insight, though dose of hallucinations was, such that a greater dose of initial, untreated hallucinations was associated with better insight at initial hospitalization (P < .01, model R(2) = 0.20). DUP was associated with global functioning (P = .05), and dose of delusions added significantly to this prediction (P = .04; model R(2) = 0.13). Doses of initial, untreated hallucinations and delusions add substantively, though differentially, to the prediction of early-course symptomatology and functioning. Findings suggest a need for focused research on frequency/severity of pretreatment psychotic symptoms beyond duration measures. © Copyright 2011 Physicians Postgraduate Press, Inc.

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

Simonen, F.A.; Johnson, K.I.; Liebetrau, A.M.

The VISA-II (Vessel Integrity Simulation Analysis code was originally developed as part of the NRC staff evaluation of pressurized thermal shock. VISA-II uses Monte Carlo simulation to evaluate the failure probability of a pressurized water reactor (PWR) pressure vessel subjected to a pressure and thermal transient specified by the user. Linear elastic fracture mechanics methods are used to model crack initiation and propagation. Parameters for initial crack size and location, copper content, initial reference temperature of the nil-ductility transition, fluence, crack-initiation fracture toughness, and arrest fracture toughness are treated as random variables. This report documents an upgraded version of themore » original VISA code as described in NUREG/CR-3384. Improvements include a treatment of cladding effects, a more general simulation of flaw size, shape and location, a simulation of inservice inspection, an updated simulation of the reference temperature of the nil-ductility transition, and treatment of vessels with multiple welds and initial flaws. The code has been extensively tested and verified and is written in FORTRAN for ease of installation on different computers. 38 refs., 25 figs.« less

Evaluation of outcome and prognostic factors for dogs living greater than one year after diagnosis of osteosarcoma: 90 cases (1997-2008).

PubMed

Culp, William T N; Olea-Popelka, Francisco; Sefton, Jennifer; Aldridge, Charles F; Withrow, Stephen J; Lafferty, Mary H; Rebhun, Robert B; Kent, Michael S; Ehrhart, Nicole

2014-11-15

To evaluate clinical characteristics, outcome, and prognostic variables in a cohort of dogs surviving > 1 year after an initial diagnosis of osteosarcoma. Retrospective case series. 90 client-owned dogs. Medical records for an 11-year period from 1997 through 2008 were reviewed, and patients with appendicular osteosarcoma that lived > 1 year after initial histopathologic diagnosis were studied. Variables including signalment, weight, serum alkaline phosphatase activity, tumor location, surgery, and adjuvant therapies were recorded. Median survival times were calculated by means of a Kaplan-Meier survival function. Univariate analysis was conducted to compare the survival function for categorical variables, and the Cox proportional hazard model was used to evaluate the likelihood of death > 1 year after diagnosis on the basis of the selected risk factors. 90 dogs met the inclusion criteria; clinical laboratory information was not available in all cases. Median age was 8.2 years (range, 2.7 to 13.3 years), and median weight was 38 kg (83.6 lb; range, 21 to 80 kg [46.2 to 176 lb]). Serum alkaline phosphatase activity was high in 29 of 60 (48%) dogs. The most common tumor location was the distal portion of the radius (54/90 [60%]). Eighty-nine of 90 (99%) dogs underwent surgery, and 78 (87%) received chemotherapy. Overall, 49 of 90 (54%) dogs developed metastatic disease. The median survival time beyond 1 year was 243 days (range, 1 to 1,899 days). Dogs that developed a surgical-site infection after limb-sparing surgery had a significantly improved prognosis > 1 year after osteosarcoma diagnosis, compared with dogs that did not develop infections. Results of the present study indicated that dogs with an initial diagnosis of osteosarcoma that lived > 1 year had a median survival time beyond the initial year of approximately 8 months. As reported previously, the development of a surgical-site infection in dogs undergoing a limb-sparing surgery significantly affected prognosis and warrants further study.

Singular vector-based targeted observations of chemical constituents: description and first application of the EURAD-IM-SVA v1.0

NASA Astrophysics Data System (ADS)

Goris, N.; Elbern, H.

2015-12-01

Measurements of the large-dimensional chemical state of the atmosphere provide only sparse snapshots of the state of the system due to their typically insufficient temporal and spatial density. In order to optimize the measurement configurations despite those limitations, the present work describes the identification of sensitive states of the chemical system as optimal target areas for adaptive observations. For this purpose, the technique of singular vector analysis (SVA), which has proven effective for targeted observations in numerical weather prediction, is implemented in the EURAD-IM (EURopean Air pollution and Dispersion - Inverse Model) chemical transport model, yielding the EURAD-IM-SVA v1.0. Besides initial values, emissions are investigated as critical simulation controlling targeting variables. For both variants, singular vectors are applied to determine the optimal placement for observations and moreover to quantify which chemical compounds have to be observed with preference. Based on measurements of the airship based ZEPTER-2 campaign, the EURAD-IM-SVA v1.0 has been evaluated by conducting a comprehensive set of model runs involving different initial states and simulation lengths. For the sake of brevity, we concentrate our attention on the following chemical compounds, O3, NO, NO2, HCHO, CO, HONO, and OH, and focus on their influence on selected O3 profiles. Our analysis shows that the optimal placement for observations of chemical species is not entirely determined by mere transport and mixing processes. Rather, a combination of initial chemical concentrations, chemical conversions, and meteorological processes determines the influence of chemical compounds and regions. We furthermore demonstrate that the optimal placement of observations of emission strengths is highly dependent on the location of emission sources and that the benefit of including emissions as target variables outperforms the value of initial value optimization with growing simulation length. The obtained results confirm the benefit of considering both initial values and emission strengths as target variables and of applying the EURAD-IM-SVA v1.0 for measurement decision guidance with respect to chemical compounds.

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

Branstator, Grant

The overall aim of our project was to quantify and characterize predictability of the climate as it pertains to decadal time scale predictions. By predictability we mean the degree to which a climate forecast can be distinguished from the climate that exists at initial forecast time, taking into consideration the growth of uncertainty that occurs as a result of the climate system being chaotic. In our project we were especially interested in predictability that arises from initializing forecasts from some specific state though we also contrast this predictability with predictability arising from forecasting the reaction of the system to externalmore » forcing – for example changes in greenhouse gas concentration. Also, we put special emphasis on the predictability of prominent intrinsic patterns of the system because they often dominate system behavior. Highlights from this work include: • Development of novel methods for estimating the predictability of climate forecast models. • Quantification of the initial value predictability limits of ocean heat content and the overturning circulation in the Atlantic as they are represented in various state of the art climate models. These limits varied substantially from model to model but on average were about a decade with North Atlantic heat content tending to be more predictable than North Pacific heat content. • Comparison of predictability resulting from knowledge of the current state of the climate system with predictability resulting from estimates of how the climate system will react to changes in greenhouse gas concentrations. It turned out that knowledge of the initial state produces a larger impact on forecasts for the first 5 to 10 years of projections. • Estimation of the predictability of dominant patterns of ocean variability including well-known patterns of variability in the North Pacific and North Atlantic. For the most part these patterns were predictable for 5 to 10 years. • Determination of especially predictable patterns in the North Atlantic. The most predictable of these retain predictability substantially longer than generic patterns, with some being predictable for two decades.« less

Improving organ donation rates by modifying the family approach process.

PubMed

Ebadat, Aileen; Brown, Carlos V R; Ali, Sadia; Guitierrez, Tim; Elliot, Eric; Dworaczyk, Sarah; Kadric, Carie; Coopwood, Ben

2014-06-01

The purpose of this study was to identify steps during family approach for organ donation that may be modified to improve consent rates of potential organ donors. Retrospective study of our local organ procurement organization (OPO) database of potential organ donors. Modifiable variables involved in the family approach of potential organ donors were collected and included race and sex of OPO representative, individual initiating approach discussion with family (RN or MD vs. OPO), length of donation discussion, use of a translator, and time of day of approach. Of 1137 potential organ donors, 661 (58%) consented and 476 (42%) declined. Consent rates were higher with matched race of donor and OPO representative (66% vs. 52%, p < 0.001), family approach by female OPO representative (67% vs. 56%, p = 0.002), if approach was initiated by OPO representative (69% vs. 49%, p < 0.001), and if consent rate was dependent on time of day the approach occurred: 6:00 am to noon (56%), noon to 6:00 pm (67%), 6:00 pm to midnight (68%), and midnight to 6:00 am (45%), p = 0.04. Family approach that led to consent lasted longer than those declining (67 vs. 43 minutes, p < 0.001). Independent predictors of consent to donation included female OPO representative (odds ratio [OR], 1.7; p = 0.006), approach discussion initiated by OPO representative (OR, 1.9; p = 0.001), and longer approach discussions (OR, 1.02; p < 0.001). The independent predictor of declined donation was the use of a translator (OR, 0.39; p = 0.01). Variables such as race and sex of OPO representative and time of day should be considered before approaching a family for organ donation. Avoiding translators during the approach process may improve donation rates. Education for health care providers should reinforce the importance of allowing OPO representatives to initiate the family approach for organ donation. Epidemiologic study, level IV. Therapeutic study, level IV.

New Perspectives on the Role of Internal Variability in Regional Climate Change and Climate Model Evaluation

NASA Astrophysics Data System (ADS)

Deser, C.

2017-12-01

Natural climate variability occurs over a wide range of time and space scales as a result of processes intrinsic to the atmosphere, the ocean, and their coupled interactions. Such internally generated climate fluctuations pose significant challenges for the identification of externally forced climate signals such as those driven by volcanic eruptions or anthropogenic increases in greenhouse gases. This challenge is exacerbated for regional climate responses evaluated from short (< 50 years) data records. The limited duration of the observations also places strong constraints on how well the spatial and temporal characteristics of natural climate variability are known, especially on multi-decadal time scales. The observational constraints, in turn, pose challenges for evaluation of climate models, including their representation of internal variability and assessing the accuracy of their responses to natural and anthropogenic radiative forcings. A promising new approach to climate model assessment is the advent of large (10-100 member) "initial-condition" ensembles of climate change simulations with individual models. Such ensembles allow for accurate determination, and straightforward separation, of externally forced climate signals and internal climate variability on regional scales. The range of climate trajectories in a given model ensemble results from the fact that each simulation represents a particular sequence of internal variability superimposed upon a common forced response. This makes clear that nature's single realization is only one of many that could have unfolded. This perspective leads to a rethinking of approaches to climate model evaluation that incorporate observational uncertainty due to limited sampling of internal variability. Illustrative examples across a range of well-known climate phenomena including ENSO, volcanic eruptions, and anthropogenic climate change will be discussed.

Trends from the Long-term Data Record and Models: What Do They Tell Us About our Ability to Predict Ozone Recovery?

NASA Technical Reports Server (NTRS)

Strahan, Susan; Stolarski, Richard; Douglass, Anne; Steenrod, Stephen

2005-01-01

Our industrial society has performed an experiment on the stratospheric ozone layer over the last several decades. The initial part of this experiment was the rapidly increasing release of halogen-containing compounds that carry chlorine and bromine to the stratosphere where they can cause a loss of ozone. The present part of this experiment is the implementation of the Montreal Protocol, which has led to a leveling off of these halogen compounds and the beginning of their slow removal from the atmosphere. The observation and attribution of ozone response to the halogens has been a particularly important and difficult task because of the impact of solar cycle uv variation, two major volcanic eruptions (El Chichon and Pinatubo), and interannual dynamic variability of the stratosphere. We have run 3 different simulations of the chemistry and transport of ozone and the minor constituents that affect ozone to help evaluate our understanding of the causes of ozone change and to assess our ability to predict ozone recovery with the removal of halogens from the stratosphere. One simulation, using the Goddard chemical transport model (CTM), had interannual variability in the dynamics for the entire 50 years of simulation, which included the past 3 decades (1974-2004) and the next 2 decades to 2022. The other two simulations used the Global Modeling Initiative (GMI) CTM with no dynamical variability: one used a the winds and temperatures from a repeating warm Arctic winter and the other used a repeating cold Arctic winter. All simulations included the effects of aerosol surfaces from volcanic eruptions on chemical reactions as well as the variation in UV over the 11-year solar cycle.

Type curves for selected problems of flow to wells in confined aquifers

USGS Publications Warehouse

Reed, J.E.

1980-01-01

This report presents type curves and related material for 11 conditions of flow to wells m confined aquifers. These solutions, compiled from hydrologic literature, span an interval of time from Theis (1935) to Papadopulos, Bredehoeft, and Cooper (1973). Solutions are presented for constant discharge, constant drawdown, and variable discharge for pumping wells that fully penetrate leaky and nonleaky aquifers. Solutions for wells that partially penetrate leaky and nonleaky aquifers are included. Also, solutions are included for the effect of finite well radius and the sudden injection of a volume of water for nonleaky aquifers. Each problem includes the partial differential equation, boundary and initial conditions, and solutions. Programs in FORTRAN for calculating additional function values are included for most of the solutions.

Constraining biosphere CO2 flux at regional scale with WRF-CO2 4DVar assimilation system

NASA Astrophysics Data System (ADS)

Zheng, T.

2017-12-01

The WRF-CO2 4DVar assimilation system is updated to include (1) operators for tower based observations (2) chemistry initial and boundary condition in the state vector (3) mechanism for aggregation from simulation model grid to state vector space. The update system is first tested with synthetic data to ensure its accuracy. The system is then used to test regional scale CO2 inversion at MCI (Midcontinental intensive) sites where CO2 mole fraction data were collected at multiple high towers during 2007-2008. The model domain is set to center on Iowa and include 8 towers within its boundary, and it is of 12x12km horizontal grid spacing. First, the relative impacts of the initial and boundary condition are assessed by the system's adjoint model. This is done with 24, 48, 72 hour time span. Second, we assessed the impacts of the transport error, including the misrepresentation of the boundary layer and cumulus activities. Third, we evaluated the different aggregation approach from the native model grid to the control variables (including scaling factors for flux, initial and boundary conditions). Four, we assessed the inversion performance using CO2 observation with different time-interval, and from different tower levels. We also examined the appropriate treatment of the background and observation error covariance in relation with these varying observation data sets.

Correlations between Learners' Initial EFL Proficiency and Variables of Clicker-Aided Flipped EFL Class

ERIC Educational Resources Information Center

Yu, Zhonggen; Yu, Liheng

2017-01-01

Although the flipped class has been hotly discussed, the clicker-aided flipped EFL class (CFEC) still remains a mystery for most scholars. This study aims to determine the correlations between the initial EFL proficiency and other variables of the clicker-aided EFL flipped class. The sample was made up of randomly selected 79 participants (Female…

Loading rate increases during barefoot running in habitually shod runners: Individual responses to an unfamiliar condition.

PubMed

Tam, Nicholas; Astephen Wilson, Janie L; Coetzee, Devon R; van Pletsen, Leanri; Tucker, Ross

2016-05-01

The purpose of this study was to examine the effect of barefoot running on initial loading rate (LR), lower extremity joint kinematics and kinetics, and neuromuscular control in habitually shod runners with an emphasis on the individual response to this unfamiliar condition. Kinematics and ground reaction force data were collected from 51 habitually shod runners during overground running in a barefoot and shod condition. Joint kinetics and stiffness were calculated with inverse dynamics. Inter-individual initial LR variability was explored by separating individuals by a barefoot/shod ratio to determine acute responders/non-responders. Mean initial LR was 54.1% greater in the barefoot when compared to the shod condition. Differences between acute responders/non-responders were found at peak and initial contact sagittal ankle angle and at initial ground contact. Correlations were found between barefoot sagittal ankle angle at initial ground contact and barefoot initial LR. A large variability in biomechanical responses to an acute exposure to barefoot running was found. A large intra-individual variability was found in initial LR but not ankle plantar-dorsiflexion between footwear conditions. A majority of habitually shod runners do not exhibit previously reported benefits in terms of reduced initial LRs when barefoot. Lastly, runners who increased LR when barefoot reduced LRs when wearing shoes to levels similar seen in habitually barefoot runners who do adopt a forefoot-landing pattern, despite increased dorsiflexion. Copyright © 2016 Elsevier B.V. All rights reserved.

Intitialization, Conceptualization, and Application in the Generalized Fractional Calculus

NASA Technical Reports Server (NTRS)

Lorenzo, Carl F.; Hartley, Tom T.

1998-01-01

This paper provides a formalized basis for initialization in the fractional calculus. The intent is to make the fractional calculus readily accessible to engineering and the sciences. A modified set of definitions for the fractional calculus is provided which formally include the effects of initialization. Conceptualizations of fractional derivatives and integrals are shown. Physical examples of the basic elements from electronics are presented along with examples from dynamics, material science, viscoelasticity, filtering, instrumentation, and electrochemistry to indicate the broad application of the theory and to demonstrate the use of the mathematics. The fundamental criteria for a generalized calculus established by Ross (1974) are shown to hold for the generalized fractional calculus under appropriate conditions. A new generalized form for the Laplace transform of the generalized differintegral is derived. The concept of a variable structure (order) differintegral is presented along with initial efforts toward meaningful definitions.

Review of the Effects of Microstructure on Fatigue in Aluminum Alloys. Ph.D. Thesis - Cincinnati Univ.

NASA Technical Reports Server (NTRS)

Telesman, J.

1984-01-01

Literature survey was conducted to determine the effects of different microstructural features and different load histories on fatigue crack initiation and propagation of aluminum alloys. Comparison of microstructure and monotonic and cyclic properties between powder metallurgy (P/M) and ingot metallurgy (I/M) alloys is presented. The two alloys that are representative of each process on which the comparison is focused are X7091 and 7050. Included is a detailed description of the microstructure produced through the P/M and I/M proesses. The effect of each pertinent microstructural feature on monotonic and cyclic properties, such as yield strength, toughness, crack initiation and propagation is discussed. Also discussed are the proposed mechanisms for crack initiation and propagation, as well as the effects of aggressive environments on these cyclic properties. The effects of variable amplitude loadin on fatigue crack propagation and the various models proposed to predict load interaction effects are discussed.

Balance control during gait initiation: State-of-the-art and research perspectives.

PubMed

Yiou, Eric; Caderby, Teddy; Delafontaine, Arnaud; Fourcade, Paul; Honeine, Jean-Louis

2017-11-18

It is well known that balance control is affected by aging, neurological and orthopedic conditions. Poor balance control during gait and postural maintenance are associated with disability, falls and increased mortality. Gait initiation - the transient period between the quiet standing posture and steady state walking - is a functional task that is classically used in the literature to investigate how the central nervous system (CNS) controls balance during a whole-body movement involving change in the base of support dimensions and center of mass progression. Understanding how the CNS in able-bodied subjects exerts this control during such a challenging task is a pre-requisite to identifying motor disorders in populations with specific impairments of the postural system. It may also provide clinicians with objective measures to assess the efficiency of rehabilitation programs and better target interventions according to individual impairments. The present review thus proposes a state-of-the-art analysis on: (1) the balance control mechanisms in play during gait initiation in able bodied subjects and in the case of some frail populations; and (2) the biomechanical parameters used in the literature to quantify dynamic stability during gait initiation. Balance control mechanisms reviewed in this article included anticipatory postural adjustments, stance leg stiffness, foot placement, lateral ankle strategy, swing foot strike pattern and vertical center of mass braking. Based on this review, the following viewpoints were put forward: (1) dynamic stability during gait initiation may share a principle of homeostatic regulation similar to most physiological variables, where separate mechanisms need to be coordinated to ensure stabilization of vital variables, and consequently; and (2) rehabilitation interventions which focus on separate or isolated components of posture, balance, or gait may limit the effectiveness of current clinical practices.

Balance control during gait initiation: State-of-the-art and research perspectives

PubMed Central

Yiou, Eric; Caderby, Teddy; Delafontaine, Arnaud; Fourcade, Paul; Honeine, Jean-Louis

2017-01-01

It is well known that balance control is affected by aging, neurological and orthopedic conditions. Poor balance control during gait and postural maintenance are associated with disability, falls and increased mortality. Gait initiation - the transient period between the quiet standing posture and steady state walking - is a functional task that is classically used in the literature to investigate how the central nervous system (CNS) controls balance during a whole-body movement involving change in the base of support dimensions and center of mass progression. Understanding how the CNS in able-bodied subjects exerts this control during such a challenging task is a pre-requisite to identifying motor disorders in populations with specific impairments of the postural system. It may also provide clinicians with objective measures to assess the efficiency of rehabilitation programs and better target interventions according to individual impairments. The present review thus proposes a state-of-the-art analysis on: (1) the balance control mechanisms in play during gait initiation in able bodied subjects and in the case of some frail populations; and (2) the biomechanical parameters used in the literature to quantify dynamic stability during gait initiation. Balance control mechanisms reviewed in this article included anticipatory postural adjustments, stance leg stiffness, foot placement, lateral ankle strategy, swing foot strike pattern and vertical center of mass braking. Based on this review, the following viewpoints were put forward: (1) dynamic stability during gait initiation may share a principle of homeostatic regulation similar to most physiological variables, where separate mechanisms need to be coordinated to ensure stabilization of vital variables, and consequently; and (2) rehabilitation interventions which focus on separate or isolated components of posture, balance, or gait may limit the effectiveness of current clinical practices. PMID:29184756

Demand Response and Energy Storage Integration Study

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

Ma, Ookie; Cheung, Kerry; Olsen, Daniel J.

2016-03-01

Demand response and energy storage resources present potentially important sources of bulk power system services that can aid in integrating variable renewable generation. While renewable integration studies have evaluated many of the challenges associated with deploying large amounts of variable wind and solar generation technologies, integration analyses have not yet fully incorporated demand response and energy storage resources. This report represents an initial effort in analyzing the potential integration value of demand response and energy storage, focusing on the western United States. It evaluates two major aspects of increased deployment of demand response and energy storage: (1) Their operational valuemore » in providing bulk power system services and (2) Market and regulatory issues, including potential barriers to deployment.« less

GaAs MMIC elements in phased-array antennas

NASA Technical Reports Server (NTRS)

Leonard, Regis F.

1988-01-01

Over the last six years NASA Lewis Research Center has carried out a program aimed at the development of advanced monolithic microwave integrated circuit technology, principally for use in phased-array antenna applications. Arising out of the Advanced Communications Technology Satellite (ACTS) program, the initial targets of the program were chips which operated at 30 and 20 GHz. Included in this group of activities were monolithic power modules with an output of 2 watts at GHz, variable phase shifters at both 20 and 30 GHz, low noise technology at 30 GHz, and a fully integrated (phase shifter, variable gain amplifier, power amplifier) transmit module at 20 GHz. Subsequent developments are centered on NASA mission requirements, particularly Space Station communications systems and deep space data communications.

[MORPHOLOGICAL VARIABILITY OF PROTEOCEPHALUS PERCAE (MÜLLER 1780) PARASITIZING COREGONID FISHES].

PubMed

Anikieva, L V; Ieshko, E P; Lebedeva, D I

2015-01-01

Morphological variability of Proteocephalus percae from native host--perch Perca fluviatilis and two species of coregonids (whitefish Coregonus lavaretus and Arctic cisco C. autumnalis) from fish farms of Karelia were studied. Parasite groups from 3 host species differed by morphometric parameters. Morphological structure of P. percae from native host included three morphs, those numbers were almost equal. Parasite groups of whitefish and Arctic cisco differed from that of perch in morphological structure and dominance of different morphs. Changes of the P. percae morphological structure was related to differences in ecological niches of three hosts of parasite. This reflects the initial stages of microevolution. The results obtained allow us to estimate an adaptive response of parasitic worms to new host species settling to pond.

Demand Response and Energy Storage Integration Study

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

Ma, Ookie; Cheung, Kerry

Demand response and energy storage resources present potentially important sources of bulk power system services that can aid in integrating variable renewable generation. While renewable integration studies have evaluated many of the challenges associated with deploying large amounts of variable wind and solar generation technologies, integration analyses have not yet fully incorporated demand response and energy storage resources. This report represents an initial effort in analyzing the potential integration value of demand response and energy storage, focusing on the western United States. It evaluates two major aspects of increased deployment of demand response and energy storage: (1) Their operational valuemore » in providing bulk power system services and (2) Market and regulatory issues, including potential barriers to deployment.« less

The role of serial free/total prostate-specific antigen ratios in a watchful observation protocol for men with localized prostate cancer.

PubMed

Do, V; Choo, R; De Boer, G; Klotz, L; Danjoux, C; Morton, G; Szumacher, E; Fleshner, N; Bunting, P

2002-05-01

To examine the change in the free/total prostate specific antigen ratio (f/tPSA) with time and to assess the potential value of serial measurements of f/tPSA as a determinant of disease progression in untreated, low-to-intermediate grade prostate cancer (T1b-T2b N0M0, Gleason score < or = 7 and PSA < or = 15 ng/mL). In a prospective single-arm cohort study from November 1995, patients were conservatively managed with watchful observation alone unless they met arbitrarily defined criteria (clinical, histological and biochemical) of disease progression. Patients were followed regularly and underwent blood tests including PSA and f/tPSA. The initial and mean f/tPSA and the rate of change of f/tPSA with time were evaluated against the rate constant for the PSA doubling time (PSATd). Correlation analyses were used to evaluate any association between baseline clinical variables and either the rate of change of f/tPSA or initial f/tPSA. As of December 2000, 161 of a total of 206 accrued patients had three or more f/tPSA measurements and formed the basis of the study (median age 70 years; median follow-up 2.7 years). The median initial f/tPSA was 0.16; there was a significant negative correlation between this value and the initial total PSA. The mean f/tPSA and rate of change of f/tPSA with time were significantly negatively correlated with the rate constant for PSATd. Also, the rate of change of f/tPSA correlated negatively with clinical T stage, but not with other baseline variables, including initial PSA, age and Gleason score. The f/tPSA in men with untreated, clinically localized prostate cancer varied widely. The negative correlation between the rate of change of f/tPSA with time and rate constant for PSATd suggests that both might provide valuable information to allow clinicians to develop a strategy for optimizing the timing of therapeutic intervention for those patients choosing watchful observation alone.

An Overview of OCTAV-UTLS (Observed Composition Trends and Variability in the UTLS), a SPARC Emerging Activity

NASA Astrophysics Data System (ADS)

Petropavlovskikh, I. V.; Manney, G. L.; Hoor, P. M.; Bourassa, A. E.; Braathen, G.; Chang, K. L.; Hegglin, M. I.; Kramarova, N. A.; Kunkel, D.; Lawrence, Z. D.; Leblanc, T.; Livesey, N. J.; Millan Valle, L. F.; Stiller, G. P.; Tegtmeier, S.; Thouret, V.; Voigt, C.; Walker, K. A.

2017-12-01

The distribution of tracers in the upper troposphere and lower stratosphere (UTLS) shows large spatial and temporal variability because of interactions of transport, chemical, and mixing processes near the tropopause, as well as variations in the location of the tropopause itself. This strongly affects quantitative estimates of the impact of radiatively active substances, including ozone and water vapour, on surface temperatures, and complicates diagnosis of dynamical processes such as stratosphere troposphere exchange (STE). The Stratosphere-troposphere Processes And their Role in Climate (SPARC) emerging activity OCTAV-UTLS (Observed Composition Trends and Variability in the UTLS) aims to reduce the uncertainties in trend estimates by accounting for these dynamically induced sources of variability. Achieving these goals by using existing UTLS trace gas observations from aircraft, ground-based, balloon and satellite platforms requires a consistent analysis of these different data with respect to the tropopause or the jets. As a central task for OCTAV-UTLS, we are developing and applying common metrics, calculated using the same reanalysis datasets, to compare UTLS data using geophysically-based coordinate systems including tropopause and upper tropospheric jet relative coordinates. In addition to assessing present day measurement capabilities, OCTAV-UTLS will assess gaps in current geographical / temporal sampling of the UTLS that limit our ability to determine atmospheric composition variability and trends. This talk will provide an overview of the OCTAV-UTLS activity and some examples of initial calculations of geophysically-based coordinates and comparisons of remapped data.

Evaluating Channel Head Conditions for Environmental Impact Assessment in Northwestern Sonoma County, California

NASA Astrophysics Data System (ADS)

Sherwood, M. N.; O'Connor, M.; Pennington, R.

2007-12-01

Erosion and sedimentation have been identified as processes significantly affecting water quality in northern California Coast Range watersheds. These watersheds, including the Gualala River watershed in northwestern Sonoma County, have been designated as having water quality impaired by sediment under provisions of the Clean Water Act Section 303(d). A study was performed to estimate potential increases in erosion rates resulting from proposed vineyard development of ridge top forestland in the Gualala River watershed. The study area has an extensive history of logging, with substantial ground disturbance from tractors. The study area is characterized by flat ridge tops with steeply incised drainages shaped by debris slides, rock slides and earth flows. Jurassic age sedimentary and meta-sedimentary rocks of the coastal and central belt Franciscan formation comprise the underlying bedrock. Channel head development and advancement has long been understood to play a key role in sediment delivery and is possibly the most sensitive to changes in the external factors such as changes in climate or land use (Dietrich and Dunne 1993). Quantifying the amount of sediment contributed by potential channel head incision and/or initiation is an objective of environmental analysis for the project. Field surveys were performed during the field seasons of 2005 and 2006 to acquire measurements of channel head locations and slope, channel dimensions and substrate associated with the proposed development sites. Analysis of this field data, including the use of ArcGIS, allowed us to examine the local relationships between variables that influence channel initiation. Variables considered include drainage area, slope, soil type, geology and vegetation. An initial analysis of a selection of area-slope data failed to produce an inverse area-slope relationship as has been found in previous studies by Montgomery and Dietrich (1988). A more complete evaluation of the entire data set is presented here.

Cost-effectiveness analysis of initial treatment strategies for mild-to-moderate Clostridium difficile infection in hospitalized patients.

PubMed

Ford, Diana C; Schroeder, Mary C; Ince, Dilek; Ernst, Erika J

2018-06-14

The cost-effectiveness of initial treatment strategies for mild-to-moderate Clostridium difficile infection (CDI) in hospitalized patients was evaluated. Decision-analytic models were constructed to compare initial treatment with metronidazole, vancomycin, and fidaxomicin. The primary model included 1 recurrence, and the secondary model included up to 3 recurrences. Model variables were extracted from published literature with costs based on a healthcare system perspective. The primary outcome was the incremental cost-effective ratio (ICER) between initial treatment strategies. In the primary model, the overall percentage of patients cured was 94.23%, 95.19%, and 96.53% with metronidazole, vancomycin, and fidaxomicin, respectively. Expected costs per case were $1,553.01, $1,306.62, and $5,095.70, respectively. In both models, vancomycin was more effective and less costly than metronidazole, resulting in negative ICERs. The ICERs for fidaxomicin compared with those for metronidazole and vancomycin in the primary model were $1,540.23 and $2,828.69 per 1% gain in cure, respectively. Using these models, a hospital currently treating initial episodes of mild-to-moderate CDI with metronidazole could expect to save $246.39-$388.37 per case treated by using vancomycin for initial therapy. A decision-analytic model revealed vancomycin to be cost-effective, compared with metronidazole, for treatment of initial episodes of mild-to-moderate CDI in adult inpatients. From the hospital perspective, initial treatment with vancomycin resulted in a higher probability of cure and a lower probability of colectomy, recurrence, persistent recurrence, and cost per case treated, compared with metronidazole. Use of fidaxomicin was associated with an increased probability of cure compared with metronidazole and vancomycin, but at a substantially increased cost. Copyright © 2018 by the American Society of Health-System Pharmacists, Inc. All rights reserved.

A Content Analysis of Television Ads: Does Current Practice Maximize Cognitive Processing?

DTIC Science & Technology

2008-12-11

ads with arousing content such as sexual imagery and fatty/sweet food imagery have the potential to stress the cognitive processing system. When the...to examine differences in content arousal , this study included variables shown to elicit arousal —loved brands, sexual images, and fatty/sweet food...loved brands as well as ads with sexual and fatty/food images are not all the same—they are not likely to be equally arousing . Initially, brands were

Biomechanics of side impact: injury criteria, aging occupants, and airbag technology.

PubMed

Yoganandan, Narayan; Pintar, Frank A; Stemper, Brian D; Gennarelli, Thomas A; Weigelt, John A

2007-01-01

This paper presents a survey of side impact trauma-related biomedical investigations with specific reference to certain aspects of epidemiology relating to the growing elderly population, improvements in technology such as side airbags geared toward occupant safety, and development of injury criteria. The first part is devoted to the involvement of the elderly by identifying variables contributing to injury including impact severity, human factors, and national and international field data. This is followed by a survey of various experimental models used in the development of injury criteria and tolerance limits. The effects of fragility of the elderly coupled with physiological changes (e.g., visual, musculoskeletal) that may lead to an abnormal seating position (termed out-of-position) especially for the driving population are discussed. Fundamental biomechanical parameters such as thoracic, abdominal and pelvic forces; upper and lower spinal and sacrum accelerations; and upper, middle and lower chest deflections under various initial impacting conditions are evaluated. Secondary variables such as the thoracic trauma index and pelvic acceleration (currently adopted in the United States Federal Motor Vehicle Safety Standards), peak chest deflection, and viscous criteria are also included in the survey. The importance of performing research studies with specific focus on out-of-position scenarios of the elderly and using the most commonly available torso side airbag as the initial contacting condition in lateral impacts for occupant injury assessment is emphasized.

Biomechanics of side impact: Injury criteria, aging occupants, and airbag technology

PubMed Central

Yoganandan, Narayan; Pintar, Frank A.; Stemper, Brian D.; Gennarelli, Thomas A.; Weigelt, John A.

2007-01-01

This paper presents a survey of side impact trauma-related biomedical investigations with specific reference to certain aspects of epidemiology relating to the growing elderly population, improvements in technology such as side airbags geared toward occupant safety, and development of injury criteria. The first part is devoted to the involvement of the elderly by identifying variables contributing to injury including impact severity, human factors, and national and international field data. This is followed by a survey of various experimental models used in the development of injury criteria and tolerance limits. The effects of fragility of the elderly coupled with physiological changes (e.g., visual, musculoskeletal) that may lead to an abnormal seating position (termed out-of-position) especially for the driving population are discussed. Fundamental biomechanical parameters such as thoracic, abdominal and pelvic forces; upper and lower spinal and sacrum accelerations; and upper, middle and lower chest deflections under various initial impacting conditions are evaluated. Secondary variables such as the thoracic trauma index and pelvic acceleration (currently adopted in the United States Federal Motor Vehicle Safety Standards), peak chest deflection, and viscous criteria are also included in the survey. The importance of performing research studies with specific focus on out-of-position scenarios of the elderly and using the most commonly available torso side airbag as the initial contacting condition in lateral impacts for occupant injury assessment is emphasized. PMID:16527285

The effect of prior healthcare employment on the wages of registered nurses.

PubMed

Yoo, Byung-Kwang; Kim, Minchul; Lin, Tzu-Chun; Sasaki, Tomoko; Ward, Debbie; Spetz, Joanne

2016-08-19

The proportion of registered nurses (RNs) with employment in health-related positions before their initial RN education has increased in the past two decades. Previous research found that prior health-related employment is positively associated with RN workforce supply, potentially due to the wage differences based on different career paths. This study's objective is to test the hypotheses that prior health-related employment is associated with differences in starting wages and with different rates of wage growth for experience as an RN. We conducted a cross-sectional analysis using the 2008 National Sample Survey of Registered Nurses (NSSRN) linked with county-level variables from the Area Health Resource File. We estimated a Heckman model where the second-stage equation's outcome variable was the logarithm of the RN hourly wage, accounting for the self-selection of working or not working as an RN (i.e., the first-stage equation's outcome variable). Key covariates included interaction terms between years of experience, experience squared, and six categories of prior health-related employment (manager, LPN/LVN, allied health, nursing aide, clerk, and all other healthcare positions). Additional covariates included demographics, weekly working hours, marital status, highest nursing degree, and county-level variables (e.g., unemployment rate). We estimated the marginal effect of experience on wage for each type of prior health-related employment, conducting separate analyses for RNs whose initial education was a Bachelor of Science in Nursing (BSN) (unweighted N = 10,345/weighted N = 945,429), RNs whose initial education was an Associate degree (unweighted N = 13,791/weighted N = 1,296,809), and total population combining the former groups (unweighted N = 24,136/weighted N = 2,242,238). Prior health-related employment was associated with higher wages, with the strongest wage differences among BSN-educated RNs. Among BSN-educated RNs, previous employment as a health care manager, LPN/LVN, or nursing aide produced statistically higher starting wages ($1.72-$3.86 per hour; $3400-$7700 per year; p = 0.006-0.08). However, experience-based wage growth was lower for BSN-educated RNs previously employed as allied health workers, LPN/LVNs, or nursing aides. Among Associate degree-educated RNs, wage difference was not observed except for higher initial wage for RNs with previous employment as LPN/LVNs. Prior employment in health-related positions was associated with both starting salary and experience-based wage growth among BSN-educated RNs. The higher wage return for those with a BSN may motivate non-RN healthcare workers to seek a BSN in their transition to RN jobs, which could help advancement toward the 80 % BSN workforce recommended by the U.S. Institute of Medicine.

Increasing Access to Oral Health Care for People Living with HIV/AIDS in the U.S.: Baseline Evaluation Results of the Innovations in Oral Health Care Initiative

PubMed Central

Fox, Jane E.; Tobias, Carol R.; Bachman, Sara S.; Reznik, David A.; Rajabiun, Serena; Verdecias, Niko

2012-01-01

Objectives We provide an overview of the Health Resources and Services Administration HIV/AIDS Bureau's Special Projects of National Significance Innovations in Oral Health Care Initiative, describe the models developed by the 15 demonstration sites and associated evaluation center, and present initial descriptive data about the characteristics of the multisite evaluation study sample. Methods Baseline data were collected from May 2007–August 2009 for 2,469 adults living with HIV/AIDS who had been without dental care, except for emergency care, for 12 months or longer. Variables included sociodemographic characteristics, HIV status, medical care, history of dental care and oral health symptoms, oral health practices, and physical and mental health quality of life. Descriptive statistics of baseline variables were calculated. Results The study sample included 2,469 adults who had been HIV-positive for a decade; most were engaged in HIV care. The majority (52.4%) of patients had not seen a dentist in more than two years; 48.2% reported an unmet oral health-care need since testing positive for HIV, and 63.2% rated the health of their teeth and gums as “fair” or “poor.” Conclusions This study is the largest to examine oral health care among people living with HIV/AIDS in more than a decade. The need for access to oral health care among members of this HIV-positive patient sample is greater than in the general population, following previous trends. Findings from our study reinforce the necessity for continued federal and statewide advocacy and support for oral health programs targeting people living with HIV/AIDS; findings can be extended to other vulnerable populations. PMID:22547872

Intrinsic platelet reactivity before start with clopidogrel as predictor for on-clopidogrel platelet function and long-term clinical outcome.

PubMed

Hochholzer, Willibald; Valina, Christian M; Bömicke, Timo; Amann, Michael; Stratz, Christian; Nührenberg, Thomas; Trenk, Dietmar; Neumann, Franz-Josef

2015-07-01

High on-clopidogrel platelet reactivity is associated with worse clinical outcome. Previous data suggest that intrinsic platelet reactivity before initiation of clopidogrel contributes significantly to on-clopidogrel platelet reactivity. It is unknown whether intrinsic reactivity can sufficiently predict on-clopidogrel reactivity and therefore identify patients with insufficient response to clopidogrel before initiation of treatment and at risk for worse clinical outcome. This analysis included 765 consecutive patients undergoing elective coronary stent implantation. Platelet reactivity was assessed by light transmission aggregometry (5 µM ADP) before administration of clopidogrel 600mg and after intake of first maintenance dose of clopidogrel on day 1 following coronary stenting. Patients were followed for up to seven years. The combined primary endpoint was death of any cause or non-fatal myocardial infarction. Intrinsic and on-clopidogrel platelet reactivity were significant correlated (r=0.31; p < 0.001). Among all tested clinical and genetic factors including the cytochrome P450 2C19*2 polymorphism, intrinsic platelet reactivity was the strongest predictor for on-clopidogrel platelet reactivity. However, intrinsic platelet reactivity could only explain 8 % of variability of on-clopidogrel platelet function. Only on-treatment platelet reactivity was predictive for long-term clinical outcome (HR 1.47, 95 % CI 1.05-2.05; p = 0.02) whereas intrinsic platelet reactivity was not (HR 1.03, 95 % CI 0.74-1.43; p = 0.86). In conclusion, intrinsic platelet reactivity before initiation of clopidogrel is the strongest predictor of early on-clopidogrel platelet reactivity but can only explain a minor proportion of its variability and is not significantly associated with clinical outcome. Thus, baseline testing cannot substitute on-clopidogrel platelet function testing.

The Variable Vector Countermeasure Suit (V2Suit) for space habitation and exploration

PubMed Central

Duda, Kevin R.; Vasquez, Rebecca A.; Middleton, Akil J.; Hansberry, Mitchell L.; Newman, Dava J.; Jacobs, Shane E.; West, John J.

2015-01-01

The “Variable Vector Countermeasure Suit (V2Suit) for Space Habitation and Exploration” is a novel system concept that provides a platform for integrating sensors and actuators with daily astronaut intravehicular activities to improve health and performance, while reducing the mass and volume of the physiologic adaptation countermeasure systems, as well as the required exercise time during long-duration space exploration missions. The V2Suit system leverages wearable kinematic monitoring technology and uses inertial measurement units (IMUs) and control moment gyroscopes (CMGs) within miniaturized modules placed on body segments to provide a “viscous resistance” during movements against a specified direction of “down”—initially as a countermeasure to the sensorimotor adaptation performance decrements that manifest themselves while living and working in microgravity and during gravitational transitions during long-duration spaceflight, including post-flight recovery and rehabilitation. Several aspects of the V2Suit system concept were explored and simulated prior to developing a brassboard prototype for technology demonstration. This included a system architecture for identifying the key components and their interconnects, initial identification of key human-system integration challenges, development of a simulation architecture for CMG selection and parameter sizing, and the detailed mechanical design and fabrication of a module. The brassboard prototype demonstrates closed-loop control from “down” initialization through CMG actuation, and provides a research platform for human performance evaluations to mitigate sensorimotor adaptation, as well as a tool for determining the performance requirements when used as a musculoskeletal deconditioning countermeasure. This type of countermeasure system also has Earth benefits, particularly in gait or movement stabilization and rehabilitation. PMID:25914631

Initial treatment seeking from professional health care providers for eating disorders: A review and synthesis of potential barriers to and facilitators of "first contact".

PubMed

Regan, Pamela; Cachelin, Fary M; Minnick, Alyssa M

2017-03-01

The objective of this study is to provide a comprehensive review of empirical research exploring barriers to and facilitators of initial treatment seeking ("first contact") from professional health care providers by adults and young adults with eating disorders (EDs). A search of databases PsycINFO and MEDLINE using the terms "treatment" and "eating disorder*" yielded 9,468 peer-reviewed articles published from January 1945 to June 2016. Screening identified 31 articles meeting the following criteria: (1) participants were 16 or older and presented with a self-reported or clinically diagnosed ED; (2) studies focused on (a) initial treatment seeking (b) for an ED (c) from professional health care providers; (3) articles were empirical, and (4) peer reviewed. Quantitative studies revealed few consistent correlates of treatment seeking, perhaps because most variables were examined in only one or two investigations. Variables with some degree of predictive utility (i.e., produced significant results in multiple studies) were age (older), ethnicity (nonethnic minority), ED type (anorexia, purging BN), specific ED-related behaviors (i.e., purging), and time spent on a treatment waitlist following referral (less). Although BMI was one of the most investigated variables, it did not predict treatment seeking. Qualitative studies revealed the following perceived barriers: (1) personal feelings of shame/fear, (2) ED-related beliefs/perceptions, (3) lack of access/availability, and (4) aspects of the treatment process. Perceived facilitators included (1) health-related concerns, (2) emotional distress, and (3) social support. Implications for clinical practice and areas for further research are discussed. Results highlight the need for shared definitions and methodologies across studies of treatment seeking. © 2017 Wiley Periodicals, Inc.

Syncope Best Practices: A Syncope Clinical Practice Guideline to Improve Quality.

PubMed

Phelps, Heather M; Sachdeva, Ritu; Mahle, William T; McCracken, Courtney E; Kelleman, Michael; McConnell, Michael; Fischbach, Peter S; Cardis, Brian M; Campbell, Robert M; Oster, Matthew E

2016-05-01

To determine whether implementation of a standardized clinical practice guideline (CPG) for the evaluation of syncope would decrease practice variability and resource utilization. A retrospective review of medical records of patients presenting to our practice for outpatient evaluation of syncope before and after implementation of the CPG. The guideline included elements of history, physical exam, electrocardiogram, and "red flags" for further testing. Outpatient pediatric cardiology offices of a large pediatric cardiology practice. All new patients between 3 and 21 years old, who presented to cardiology clinic with a chief complaint of syncope. The CPG for the evaluation of pediatric syncope was presented to the providers. Resource utilization was determined by the tests ordered by individual physicians before and after initiation of the CPG. Patient final diagnoses were recorded and the medical records were subsequently reviewed to determine if any patients, who presented again to the system, were ultimately diagnosed with cardiac disease. Of the 1496 patients with an initial visit for syncope, there was no significant difference in the diagnosis of cardiac disease before or after initiation of the CPG: (0.6% vs. 0.4%, P = .55). Electrocardiography provides the highest yield in the evaluation of pediatric syncope. Despite high compliance (86.9%), there were no overall changes in costs ($346.31 vs. $348.53, P = .85) or in resource utilization. There was, however, a decrease in the variability of ordering of echocardiograms among physicians, particularly among those at the extremes of utilization. Although the CPG did not decrease already low costs, it did decrease the wide variability in echo utilization. Evaluation beyond detailed history, physical exam, and electrocardiography provides no additional benefit in the evaluations of pediatric patients presenting with syncope. © 2015 Wiley Periodicals, Inc.

Probabilistic modeling of anatomical variability using a low dimensional parameterization of diffeomorphisms.

PubMed

Zhang, Miaomiao; Wells, William M; Golland, Polina

2017-10-01

We present an efficient probabilistic model of anatomical variability in a linear space of initial velocities of diffeomorphic transformations and demonstrate its benefits in clinical studies of brain anatomy. To overcome the computational challenges of the high dimensional deformation-based descriptors, we develop a latent variable model for principal geodesic analysis (PGA) based on a low dimensional shape descriptor that effectively captures the intrinsic variability in a population. We define a novel shape prior that explicitly represents principal modes as a multivariate complex Gaussian distribution on the initial velocities in a bandlimited space. We demonstrate the performance of our model on a set of 3D brain MRI scans from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database. Our model yields a more compact representation of group variation at substantially lower computational cost than the state-of-the-art method such as tangent space PCA (TPCA) and probabilistic principal geodesic analysis (PPGA) that operate in the high dimensional image space. Copyright © 2017 Elsevier B.V. All rights reserved.

Word naming times and psycholinguistic norms for Italian nouns.

PubMed

Barca, Laura; Burani, Cristina; Arduino, Lisa S

2002-08-01

The present study describes normative measures for 626 Italian simple nouns. The database (LEXVAR.XLS) is freely available for down-loading on the Web site http://wwwistc.ip.rm.cnr.it/materia/database/. For each of the 626 nouns, values for the following variables are reported: age of acquisition, familiarity, imageability, concreteness, adult written frequency, child written frequency, adult spoken frequency, number of orthographic neighbors, mean bigram frequency, length in syllables, and length in letters. A classification of lexical stress and of the type of word-initial phoneme is also provided. The intercorrelations among the variables, a factor analysis, and the effects of variables and of the extracted factors on word naming are reported. Naming latencies were affected primarily by a factor including word length and neighborhood size and by a word frequency factor. Neither a semantic factor including imageability, concreteness, and age of acquisition nor a factor defined by mean bigram frequency had significant effects on pronunciation times. These results hold for a language with shallow orthography, like Italian, for which lexical nonsemantic properties have been shown to affect reading aloud. These norms are useful in a variety of research areas involving the manipulation and control of stimulus attributes.

Multivariate analyses of tinnitus complaint and change in tinnitus complaint: a masker study.

PubMed

Jakes, S; Stephens, S D

1987-11-01

Multivariate statistical techniques were used to re-analyse the data from the recent DHSS multi-centre masker study. These analyses were undertaken to three ends. First, to clarify and attempt to replicate the previously found factor structure of complaints about tinnitus. Secondly, to attempt to identify common factors in the change or improvement measures pre- and post-masker treatment. Thirdly, to identify predictors of any such outcome factors. Two complaint factors were identified; 'Distress' and 'intrusiveness'. A series of analyses were conducted on change measures using different numbers of subjects and variables. When only semantic differential scales were used, the change factors were very similar to the complaint factors noted above. When variables measuring other aspects of improvement were included, several other factors were identified. These included; 'tinnitus helped', 'masking effects', 'residual inhibition' and 'matched loudness'. Twenty-five conceptually distinct predictors of outcome were identified. These predictor variables were quite different for different outcome factors. For example, high-frequency hearing loss was a predictor of tinnitus being helped by the masker, and a low frequency match and a low masking threshold predicted therapeutic success on residual inhibition. Decrease in matched loudness was predicted by louder tinnitus initially.

Datalist: A Value Added Service to Enable Easy Data Selection

NASA Technical Reports Server (NTRS)

Li, Angela; Hegde, Mahabaleshwa; Bryant, Keith; Seiler, Edward; Shie, Chung-Lin; Teng, William; Liu, Zhong; Hearty, Thomas; Shen, Suhung; Kempler, Steven;

Palliative care and prognosis in COPD: a systematic review with a validation cohort.

PubMed

Almagro, Pere; Yun, Sergi; Sangil, Ana; Rodríguez-Carballeira, Mónica; Marine, Meritxell; Landete, Pedro; Soler-Cataluña, Juan José; Soriano, Joan B; Miravitlles, Marc

2017-01-01

Current recommendations to consider initiation of palliative care (PC) in COPD patients are often based on an expected poor prognosis. However, this approach is not evidence-based, and which and when COPD patients should start PC is controversial. We aimed to assess whether current suggested recommendations for initiating PC were sufficiently reliable. We identified prognostic variables proposed in the literature for initiating PC; then, we ascertained their relationship with 1-year mortality, and finally, we validated their utility in our cohort of 697 patients hospitalized for COPD exacerbation. From 24 articles of 499 screened, we selected 20 variables and retrieved 48 original articles in which we were able to calculate the relationship between each of them and 1-year mortality. The number of studies where 1-year mortality was detailed for these variables ranged from 9 for previous hospitalizations or FEV 1 ≤30% to none for albumin ≤25 mg/dL. The percentage of 1-year mortality in the literature for these variables ranged from 5% to 60%. In the validation cohort study, the prevalence of these proposed variables ranged from 8% to 64%; only 10 of the 18 variables analyzed in our cohort reached statistical significance with Cox regression analysis, and none overcame an area under the curve ≥0.7. We conclude that none of the suggested criteria for initiating PC based on an expected poor vital prognosis in COPD patients in the short or medium term offers sufficient reliability, and consequently, they should be avoided as exclusive criteria for considering PC or at least critically appraised.

Palliative care and prognosis in COPD: a systematic review with a validation cohort

PubMed Central

Almagro, Pere; Yun, Sergi; Sangil, Ana; Rodríguez-Carballeira, Mónica; Marine, Meritxell; Landete, Pedro; Soler-Cataluña, Juan José; Soriano, Joan B; Miravitlles, Marc

2017-01-01

Current recommendations to consider initiation of palliative care (PC) in COPD patients are often based on an expected poor prognosis. However, this approach is not evidence-based, and which and when COPD patients should start PC is controversial. We aimed to assess whether current suggested recommendations for initiating PC were sufficiently reliable. We identified prognostic variables proposed in the literature for initiating PC; then, we ascertained their relationship with 1-year mortality, and finally, we validated their utility in our cohort of 697 patients hospitalized for COPD exacerbation. From 24 articles of 499 screened, we selected 20 variables and retrieved 48 original articles in which we were able to calculate the relationship between each of them and 1-year mortality. The number of studies where 1-year mortality was detailed for these variables ranged from 9 for previous hospitalizations or FEV1 ≤30% to none for albumin ≤25 mg/dL. The percentage of 1-year mortality in the literature for these variables ranged from 5% to 60%. In the validation cohort study, the prevalence of these proposed variables ranged from 8% to 64%; only 10 of the 18 variables analyzed in our cohort reached statistical significance with Cox regression analysis, and none overcame an area under the curve ≥0.7. We conclude that none of the suggested criteria for initiating PC based on an expected poor vital prognosis in COPD patients in the short or medium term offers sufficient reliability, and consequently, they should be avoided as exclusive criteria for considering PC or at least critically appraised. PMID:28652724

Sleep variability and fatigue in adolescents: Associations with school-related features.

PubMed

Matos, M G; Gaspar, T; Tomé, G; Paiva, T

2016-10-01

This study aims to evaluate the influences of sleep duration and sleep variability (SleepV), upon adolescents' school-related situations. The Health Behaviour in School-Aged Children (HBSC) survey is based on a self-completed questionnaire. The participants were 3164 pupils (53.7% girls), attending the 8th and 10th grades, 14.9 years old, and were inquired about subjective sleep duration during the week and weekends, SleepV, fatigue, difficulties in sleep initiation, school achievement, feelings towards schools, pressure with school work and skipping classes. Multiple regression models used, as dependent variables: (a) school achievement, (b) disliking school, (c) pressure with school work and (d) skipping classes, using as independent variables, each of the remaining school-related variables, fatigue, total sleep duration and difficulties in sleep initiation. The average sleep duration in the week and during weekdays was lower than recommended for these age groups, and almost half of students had high SleepV between weekdays and weekends. A logistic model revealed that the absence of SleepV was associated with lower perception of school work pressure, less frequent skipping classes, more infrequent fatigue and more infrequent difficulties in sleep initiation. Poor sleep quality, SleepV and insufficient sleep duration affected negatively school-related variables. © 2015 International Union of Psychological Science.

K-Means Algorithm Performance Analysis With Determining The Value Of Starting Centroid With Random And KD-Tree Method

NASA Astrophysics Data System (ADS)

Sirait, Kamson; Tulus; Budhiarti Nababan, Erna

2017-12-01

Clustering methods that have high accuracy and time efficiency are necessary for the filtering process. One method that has been known and applied in clustering is K-Means Clustering. In its application, the determination of the begining value of the cluster center greatly affects the results of the K-Means algorithm. This research discusses the results of K-Means Clustering with starting centroid determination with a random and KD-Tree method. The initial determination of random centroid on the data set of 1000 student academic data to classify the potentially dropout has a sse value of 952972 for the quality variable and 232.48 for the GPA, whereas the initial centroid determination by KD-Tree has a sse value of 504302 for the quality variable and 214,37 for the GPA variable. The smaller sse values indicate that the result of K-Means Clustering with initial KD-Tree centroid selection have better accuracy than K-Means Clustering method with random initial centorid selection.

Inter-observer variability in diagnosing radiological features of aneurysmal subarachnoid hemorrhage; a preliminary single centre study comparing observers from different specialties and levels of training.

PubMed

Siddiqui, Usman T; Khan, Anjum F; Shamim, Muhammad Shahzad; Hamid, Rana Shoaib; Alam, Muhammad Mehboob; Emaduddin, Muhammad

2014-01-01

A noncontrast computed tomography (CT) scan remains the initial radiological investigation of choice for a patient with suspected aneurysmal subarachnoid hemorrhage (aSAH). This initial scan may be used to derive key information about the underlying aneurysm which may aid in further management. The interpretation, however, is subject to the skill and experience of the interpreting individual. The authors here evaluate the interpretation of such CT scans by different individuals at different levels of training, and in two different specialties (Radiology and Neurosurgery). Initial nonontrast CT scan of 35 patients with aSAH was evaluated independently by four different observers. The observers selected for the study included two from Radiology and two from Neurosurgery at different levels of training; a resident currently in mid training and a resident who had recently graduated from training of each specialty. Measured variables included interpreter's suspicion of presence of subarachnoid blood, side of the subarachnoid hemorrhage, location of the aneurysm, the aneurysm's proximity to vessel bifurcation, number of aneurysm(s), contour of aneurysm(s), presence of intraventricular hemorrhage (IVH), intracerebral hemorrhage (ICH), infarction, hydrocephalus and midline shift. To determine the inter-observer variability (IOV), weighted kappa values were calculated. There was moderate agreement on most of the CT scan findings among all observers. Substantial agreement was found amongst all observers for hydrocephalus, IVH, and ICH. Lowest agreement rates were seen in the location of aneurysm being supra or infra tentorial. There were, however, some noteworthy exceptions. There was substantial to almost perfect agreement between the radiology graduate and radiology resident on most CT findings. The lowest agreement was found between the neurosurgery graduate and the radiology graduate. Our study suggests that although agreements were seen in the interpretation of some of the radiological features of aSAH, there is still considerable IOV in the interpretation of most features among physicians belonging to different levels of training and different specialties. Whether these might affect management or outcome is unclear.

Factors influencing delay in the diagnosis of colorectal cancer: a study protocol

PubMed Central

Esteva, Magdalena; Ramos, Maria; Cabeza, Elena; Llobera, Joan; Ruiz, Amador; Pita, Salvador; Segura, Josep M; Cortés, Jose M; González-Lujan, Luis

2007-01-01

Background Colorectal cancer (CRC) is the second most frequent tumor in developed countries. Since survival from CRC depends mostly on disease stage at the time of diagnosis, individuals with symptoms or signs suspicious of CRC should be examined without delay. Many factors, however, intervene between symptom onset and diagnosis. This study was designed to: 1) Describe the diagnostic process of CRC from the onset of first symptoms to diagnosis and treatment. 2) Establish the time interval from initial symptoms to diagnosis and treatment, globally and considering patient's and doctors' delay, with the latter due to family physician and/or hospital services. 3) Identify the factors related to defined types of delay. 4) Assess the concordance between information included in primary health care and hospital clinical records regarding onset of first symptoms. Methods/Design Descriptive study, coordinated, with 5 participant groups of 5 different Spanish regions (Balearic Islands, Galicia, Catalunya, Aragón and Valencia Health Districts), with a total of 8 acute public hospitals and 140 primary care centers. Incident cases of CRC during the study period, as identified from pathology services at the involved hospitals. A sample size of 896 subjects has been estimated, 150 subjects for each participant group. Information will be collected through patient interviews and primary health care and hospital clinical records. Patient variables will include sociodemographic variables, family history of cancer, symptom perception, and confidence in the family physician; tumor variables will include tumor site, histological type, grade and stage; symptom variables will include date of onset, type and number of symptoms; health system variables will include number of patient contacts with family physician, type and content of the referral, hospital services attending the patient, diagnostic modalities and results; and delay intervals, including global delays and delays attributed to the patient, family physician and hospital. Discussion To obtain a nonrestricted sample of patients with CRC we have minimized selection risk by identifying the patients from pathology services. A greater constraint may be associated with information sources based on clinical records. Due to inherent features of coordinated studies, it is important to standardize the collection of information. PMID:17697332

Analysis of Lower Body Kinematic and Kinetic: Differences Between Age and Handicap in Golfers of Various Ages and Skill Levels

NASA Astrophysics Data System (ADS)

Smilensky, Alexander

The purpose of this thesis was to provide a preliminary analysis of lower body golf swing biomechanics. Fourteen golfers of various ages and handicaps performed 10 swings off a tee with their driver. This study focused on a number of dependent variables including lead knee joint flexion angles, internal/external rotations, valgus/varus angles, as well as ground reaction forces normalized to body weight (%BW), X-Factor angle and club head velocity. Dependent variables were analyzed at four specifically defined events (start, initiation of downswing, contact and swing termination). Simple linear regressions were performed using age and handicap as independent variables to see if patterns could be determined at any of the events. No significant trends or results were reported within our sample. An analysis of variance (ANOVA) was then used to examine the effect of event on specific dependent variables. A number of differences were reported within each of the variables across the four events. This study hoped to provide a more comprehensive understanding of the movement patterns occurring at the lower body with special focus on the lead knee.

Size, Loading Efficiency, and Cytotoxicity of Albumin-Loaded Chitosan Nanoparticles: An Artificial Neural Networks Study.

PubMed

Baharifar, Hadi; Amani, Amir

2017-01-01

When designing nanoparticles for drug delivery, many variables such as size, loading efficiency, and cytotoxicity should be considered. Usually, smaller particles are preferred in drug delivery because of longer blood circulation time and their ability to escape from immune system, whereas smaller nanoparticles often show increased toxicity. Determination of parameters which affect size of particles and factors such as loading efficiency and cytotoxicity could be very helpful in designing drug delivery systems. In this work, albumin (as a protein drug model)-loaded chitosan nanoparticles were prepared by polyelectrolyte complexation method. Simultaneously, effects of 4 independent variables including chitosan and albumin concentrations, pH, and reaction time were determined on 3 dependent variables (i.e., size, loading efficiency, and cytotoxicity) by artificial neural networks. Results showed that concentrations of initial materials are the most important factors which may affect the dependent variables. A drop in the concentrations decreases the size directly, but they simultaneously decrease loading efficiency and increase cytotoxicity. Therefore, an optimization of the independent variables is required to obtain the most useful preparation. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

Stability analysis of spectral methods for hyperbolic initial-boundary value systems

NASA Technical Reports Server (NTRS)

Gottlieb, D.; Lustman, L.; Tadmor, E.

1986-01-01

A constant coefficient hyperbolic system in one space variable, with zero initial data is discussed. Dissipative boundary conditions are imposed at the two points x = + or - 1. This problem is discretized by a spectral approximation in space. Sufficient conditions under which the spectral numerical solution is stable are demonstrated - moreover, these conditions have to be checked only for scalar equations. The stability theorems take the form of explicit bounds for the norm of the solution in terms of the boundary data. The dependence of these bounds on N, the number of points in the domain (or equivalently the degree of the polynomials involved), is investigated for a class of standard spectral methods, including Chebyshev and Legendre collocations.

The 200-kilowatt wind turbine project

NASA Technical Reports Server (NTRS)

1978-01-01

The three 200 kilowatt wind turbines described, compose the first of three separate systems. Proposed wind turbines of the two other systems, although similar in design, are larger in both physical size and rated power generation. The overall objective of the project is to obtain early operation and performance data while gaining initial experience in the operation of large, horizontal-axis wind turbines in typical utility environments. Several of the key issues addressed include the following: (1) impact of the variable power output (due to varying wind speeds) on the utility grid (2) compatibility with utility requirements (voltage and frequency control of generated power) (3) demonstration of unattended, fail-safe operation (4) reliability of the wind turbine system (5) required maintenance and (6) initial public reaction and acceptance.

Remission of relapsing polychondritis after successful treatment of myelodysplastic syndrome with azacitidine: a case and review of the literature.

PubMed

Erden, Abdulsamet; Bilgin, Emre; Kılıç, Levent; Sarı, Alper; Armağan, Berkan; Büyükaşık, Yahya; Kalyoncu, Umut

2018-05-01

Relapsing polychondritis (RP) is a rare autoimmune disorder, and myelodysplastic syndrome (MDS) is accompanied by RP at variable rates. Herein, we report a case with RP and MDS who responded dramatically to 5-azacitidine for MDS. With conventional immunosuppressive treatment, our patient had several episodes of different side effects, including infections. With the diagnosis of MDS and initiation of azacitidine treatment, all the manifestations of RP disappeared, and remission was achieved for MDS. Although he had relapses of either RP or MDS after several years of azacitidine treatment, all relapses were controlled well with the initiation of azacitidine treatment every time. Azacitidine should be kept in mind as a treatment option for RP patients with MDS.

Delay of Treatment Initiation Does Not Adversely Affect Survival Outcome in Breast Cancer.

PubMed

Yoo, Tae-Kyung; Han, Wonshik; Moon, Hyeong-Gon; Kim, Jisun; Lee, Jun Woo; Kim, Min Kyoon; Lee, Eunshin; Kim, Jongjin; Noh, Dong-Young

2016-07-01

Previous studies examining the relationship between time to treatment and survival outcome in breast cancer have shown inconsistent results. The aim of this study was to analyze the overall impact of delay of treatment initiation on patient survival and to determine whether certain subgroups require more prompt initiation of treatment. This study is a retrospective analysis of stage I-III patients who were treated in a single tertiary institution between 2005 and 2008. Kaplan-Meier survival analysis and Cox proportional hazards regression model were used to evaluate the impact of interval between diagnosis and treatment initiation in breast cancer and various subgroups. A total of 1,702 patients were included. Factors associated with longer delay of treatment initiation were diagnosis at another hospital, medical comorbidities, and procedures performed before admission for surgery. An interval between diagnosis and treatment initiation as a continuous variable or with a cutoff value of 15, 30, 45, and 60 days had no impact on disease-free survival (DFS). Subgroup analyses for hormone-responsiveness, triple-negative breast cancer, young age, clinical stage, and type of initial treatment showed no significant association between longer delay of treatment initiation and DFS. Our results show that an interval between diagnosis and treatment initiation of 60 days or shorter does not appear to adversely affect DFS in breast cancer.

Effect of Understress on Fretting Fatigue Crack Initiation of Press-Fitted Axle

NASA Astrophysics Data System (ADS)

Kubota, Masanobu; Niho, Sotaro; Sakae, Chu; Kondo, Yoshiyuki

Axles are one of the most important components in railway vehicles with regard to safety, since a fail-safe design is not available. The problems of fretting fatigue crack initiation in a press-fitted axle have not been completely solved even though up-to-date fatigue design methods are employed. The objective of the present study is to clarify the effect of understress on fretting fatigue crack initiation behavior in the press-fitted axle. Most of the stress amplitude given to the axle in service is smaller than the fretting fatigue limit based on the stress to initiate cracks under a constant load σwf1. Rotating bending fatigue tests were performed using a 40mm-diameter press-fitted axle assembly. Two-step variable stresses consisting of σwf1 and half or one-third of σwf1 were used in the experiment. Crack initiation life was defined as the number of cycles when a fretting fatigue crack, which is longer than 30µm, was found using a metallurgical microscope. Fretting fatigue cracks were initiated even when the variable stress did not contain the stress above the fretting fatigue crack initiation limit. The crack initiation life varied from 4.0×107 to 1.2×108 depending on the stress frequency ratio nL/nH. The sum of the number of cycles of higher stress at crack initiation NH was much smaller than the number of cycles to initiate cracks estimated from the modified Miner's rule. The value of the modified Miner's damage ranged from 0.013 to 0.185. To clarify the effect of variable amplitude on the fretting fatigue crack initiation, a comprehensive investigation related to relative slip, tangential force and fretting wear is necessary.

Initiation of Coitus in Early Adolescence.

ERIC Educational Resources Information Center

Udry, J. Richard; Billy, John O. G.

1987-01-01

White males' initiation of coitus in early adolescence is dominated by motivational hormone effects and social attractiveness. White females' initiation of coitus is dominated by the effects of social controls. Black females' initiation of coitus is dominated by their level of pubertal development, an attractiveness variable. (Author/BJV)

Geomorphological control on variably saturated hillslope hydrology and slope instability

USGS Publications Warehouse

Giuseppe, Formetta; Simoni, Silvia; Godt, Jonathan W.; Lu, Ning; Rigon, Riccardo

2016-01-01

In steep topography, the processes governing variably saturated subsurface hydrologic response and the interparticle stresses leading to shallow landslide initiation are physically linked. However, these processes are usually analyzed separately. Here, we take a combined approach, simultaneously analyzing the influence of topography on both hillslope hydrology and the effective stress fields within the hillslope itself. Clearly, runoff and saturated groundwater flow are dominated by gravity and, ultimately, by topography. Less clear is how landscape morphology influences flows in the vadose zone, where transient fluxes are usually taken to be vertical. We aim to assess and quantify the impact of topography on both saturated and unsaturated hillslope hydrology and its effects on shallow slope stability. Three real hillslope morphologies (concave, convex, and planar) are analyzed using a 3-D, physically based, distributed model coupled with a module for computation of the probability of failure, based on the infinite slope assumption. The results of the analyses, which included parameter uncertainty analysis of the results themselves, show that convex and planar slopes are more stable than concave slopes. Specifically, under the same initial, boundary, and infiltration conditions, the percentage of unstable areas ranges from 1.3% for the planar hillslope, 21% for convex, to a maximum value of 33% for the concave morphology. The results are supported by a sensitivity analysis carried out to examine the effect of initial conditions and rainfall intensity.

[Trajectories of aging in a sample of elderly people: a longitudinal study].

PubMed

Navarro-González, Elena; Calero, María Dolores; Becerra-Reina, Dolores

2015-01-01

The present study analyzes variables associated with different trajectories of aging, and the level of cognitive functioning in a sample of older adults. Although this work is part of a broader investigation where initially 141 people were assessed, this paper only discusses the cognitive functioning and cognitive development of 64 older people who have been followed up four years after the initial assessment, with a mean age of 83.84 years (age range 65 to 99 years). In the initial assessment all the participants were assessed with a psychological battery that included the MEC, the verbal fluency task FVS, a sustained attention task, a working memory test, a Quality of Life Questionnaire, a scale of dependency, and the AVLT-Learning Potential test. In the follow up assessment, participants have been assessed with the MEC, the verbal fluency task FVS, and the verbal memory test AVLT-PA. the results show relatively stable trajectories of aging and that the variables that better predict cognitive evolution of the elderly are working memory and post-test score in the AVLT-LP. Despite the time lapse between the two assessments and the age of the participants, older adults have remained relatively stable in their cognitive functioning, which in part contradicts the idea that--especially after 80 years--a general decline of cognitive functioning occurs in old age. Copyright © 2014 SEGG. Published by Elsevier Espana. All rights reserved.

Hair Cortisol in Twins: Heritability and Genetic Overlap with Psychological Variables and Stress-System Genes.

PubMed

Rietschel, Liz; Streit, Fabian; Zhu, Gu; McAloney, Kerrie; Frank, Josef; Couvy-Duchesne, Baptiste; Witt, Stephanie H; Binz, Tina M; McGrath, John; Hickie, Ian B; Hansell, Narelle K; Wright, Margaret J; Gillespie, Nathan A; Forstner, Andreas J; Schulze, Thomas G; Wüst, Stefan; Nöthen, Markus M; Baumgartner, Markus R; Walker, Brian R; Crawford, Andrew A; Colodro-Conde, Lucía; Medland, Sarah E; Martin, Nicholas G; Rietschel, Marcella

2017-11-10

Hair cortisol concentration (HCC) is a promising measure of long-term hypothalamus-pituitary-adrenal (HPA) axis activity. Previous research has suggested an association between HCC and psychological variables, and initial studies of inter-individual variance in HCC have implicated genetic factors. However, whether HCC and psychological variables share genetic risk factors remains unclear. The aims of the present twin study were to: (i) assess the heritability of HCC; (ii) estimate the phenotypic and genetic correlation between HPA axis activity and the psychological variables perceived stress, depressive symptoms, and neuroticism; using formal genetic twin models and molecular genetic methods, i.e. polygenic risk scores (PRS). HCC was measured in 671 adolescents and young adults. These included 115 monozygotic and 183 dizygotic twin-pairs. For 432 subjects PRS scores for plasma cortisol, major depression, and neuroticism were calculated using data from large genome wide association studies. The twin model revealed a heritability for HCC of 72%. No significant phenotypic or genetic correlation was found between HCC and the three psychological variables of interest. PRS did not explain variance in HCC. The present data suggest that HCC is highly heritable. However, the data do not support a strong biological link between HCC and any of the investigated psychological variables.

Explanatory model of emotional-cognitive variables in school mathematics performance: a longitudinal study in primary school.

PubMed

Cerda, Gamal; Pérez, Carlos; Navarro, José I; Aguilar, Manuel; Casas, José A; Aragón, Estíbaliz

2015-01-01

This study tested a structural model of cognitive-emotional explanatory variables to explain performance in mathematics. The predictor variables assessed were related to students' level of development of early mathematical competencies (EMCs), specifically, relational and numerical competencies, predisposition toward mathematics, and the level of logical intelligence in a population of primary school Chilean students (n = 634). This longitudinal study also included the academic performance of the students during a period of 4 years as a variable. The sampled students were initially assessed by means of an Early Numeracy Test, and, subsequently, they were administered a Likert-type scale to measure their predisposition toward mathematics (EPMAT) and a basic test of logical intelligence. The results of these tests were used to analyse the interaction of all the aforementioned variables by means of a structural equations model. This combined interaction model was able to predict 64.3% of the variability of observed performance. Preschool students' performance in EMCs was a strong predictor for achievement in mathematics for students between 8 and 11 years of age. Therefore, this paper highlights the importance of EMCs and the modulating role of predisposition toward mathematics. Also, this paper discusses the educational role of these findings, as well as possible ways to improve negative predispositions toward mathematical tasks in the school domain.

From cannabis initiation to daily use: educational inequalities in consumption behaviours over three generations in France.

PubMed

Legleye, Stéphane; Khlat, Myriam; Mayet, Aurélie; Beck, François; Falissard, Bruno; Chau, Nearkasen; Peretti-Watel, Patrick

2016-10-01

The diffusion of cannabis initiation has been accompanied by a reversal in the educational gradient: contrary to older generations, the less educated in recent generations are more likely to initiate than the more educated. We tested whether the educational gradient for the transition from initiation to daily use evolved in the same way. A French telephone random survey conducted in 2010 (21 818 respondents aged 15-64 years), asking interviewees about their ages at initiation to daily use, if any. A total of 6824 cannabis initiators aged 18-64 years at data collection. Three birth cohort groups (generations) were compared: 1946-60 (n = 767), 1961-75 (n = 2632) and 1976-92 (n = 3425) with, respectively, 47, 42 and 45% of women. Risks of transition to daily use from ages 11-34 were compared through time-discrete logistic regressions and educational gradients were quantified through a relative index of inequality (RII). Control variables include age and time-varying variables (ages at tobacco daily use, at first drunkenness and at first other use of an illicit drug in a list of 13 products). Twenty-four per cent of the initiators reported daily use before age 35, the proportions tripling from the oldest to the youngest generation (from 11.7 to 38.6% in men, from 7.7 to 22.2% in women). Whatever the generation, the less educated initiators more often shifted to daily use than the most educated: from the oldest to the youngest generation, RII = 2.13, 95% confidence interval (CI) = [0.65, 7.02]; 2.19 95% CI = [1.33, 3.63]; and 2.24, 95% CI = [1.60, 3.15] in men; RII = 3.31, 95% CI = [0.75, 14.68]; 3.17, 95% CI = [1.49, 6.76]; and 3.56, 95% CI = [2.07, 6.14] in women, respectively. In France, the risk of transition from cannabis initiation to daily use has remained consistently higher among less educated cannabis initiators over three generations (1946-60, 1961-75, 1976-92), in contrast to what is observed for initiation. © 2016 Society for the Study of Addiction.

Interannual Variability of Ammonia Concentrations over the United States: Sources and Implications for Inorganic Particulate Matter

NASA Astrophysics Data System (ADS)

Schiferl, L. D.; Heald, C. L.; Van Damme, M.; Pierre-Francois, C.; Clerbaux, C.

2015-12-01

Modern agricultural practices have greatly increased the emission of ammonia (NH3) to the atmosphere. Recent controls to reduce the emissions of sulfur and nitrogen oxides (SOX and NOX) have increased the importance of understanding the role ammonia plays in the formation of surface fine inorganic particulate matter (PM2.5) in the United States. In this study, we identify the interannual variability in ammonia concentration, explore the sources of this variability and determine their contribution to the variability in surface PM2.5 concentration. Over the summers of 2008-2012, measurements from the Ammonia Monitoring Network (AMoN) and the Infrared Atmospheric Sounding Interferometer (IASI) satellite instrument show considerable variability in both surface and column ammonia concentrations (+/- 29% and 28% of the mean), respectively. This observed variability is larger than that simulated by the GEOS-Chem chemical transport model, where meteorology dominates the variability in ammonia and PM2.5 concentrations compared to the changes caused by SOX and NOX reductions. Our initial simulation does not include year-to-year changes in ammonia agricultural emissions. We use county-wide information on fertilizer sales and livestock populations, as well as meteorological variations to account for the interannual variability in agricultural activity and ammonia volatilization. These sources of ammonia emission variability are important for replicating observed variations in ammonia and PM2.5, highlighting how accurate ammonia emissions characterization is central to PM air quality prediction.

Development of a non-piston MR suspension rod for variable mass systems

NASA Astrophysics Data System (ADS)

Deng, Huaxia; Han, Guanghui; Zhang, Jin; Wang, Mingxian; Ma, Mengchao; Zhong, Xiang; Yu, Liandong

2018-06-01

The semi-active suspension systems for variable mass systems require long work stroke and variable damping, while the currently piston structure limits the work stroke for the magnetorheological (MR) dampers. The main work of this paper is to design a semi-active non-piston MR (NPMR) suspension rod for the reduction of the vibration of an automatic impeller washing machine, which is a typical variable mass system. The designed suspension rod locates in the suspension system that links the internal tub to the washing machine cabinet. The NPMR suspension rod includes a MR part and a air part. The MR part can provide low initial damping force and the unlimited work stroke compared with the piston MR damper. The hysteretic response tests and vibration performance evaluation with different loadings are conducted to verify the dynamic performance for the designed rod. The measured damping force of the MR part varies from 5 to 20 N. Studies of dehydration mode experiments of the washing machine indicate that its vibration acceleration with the NPMR suspension rods can reduce to half of the original passive ones in certain conditions.

Shoulder Pain, Functional Status, and Health-Related Quality of Life after Head and Neck Cancer Surgery

PubMed Central

Wang, Hsiao-Lan; Keck, Juanita F.; Weaver, Michael T.; Mikesky, Alan; Bunnell, Karen; Buelow, Janice M.; Rawl, Susan M.

2013-01-01

Head and neck cancer (HNC) patients experience treatment-related complications that may interfere with health-related quality of life (HRQOL). The purpose of this study was to describe the symptom experience (shoulder pain) and functional status factors that are related to global and domain-specific HRQOL at one month after HNC surgery. In this exploratory study, we examined 29 patients. The outcome variables included global HRQOL as well as physical, functional, emotional, and social well-being. Symptom experience and functional status factors were the independent variables. In the symptom experience variables, shoulder pain distress was negatively associated with physical well-being (R 2 = 0.24). Among the functional status variables, eating impairment was negatively related to global HRQOL (R 2 = 0.18) and physical well-being (R 2 = 0.21). Speaking impairment and impaired body image explained a large amount of the variance in functional well-being (R 2 = 0.45). This study provided initial results regarding symptom experience and functional status factors related to poor HRQOL in the early postoperative period for HNC patients. PMID:24455274

Factors associated with delayed recovery in athletes with concussion treated at a pediatric neurology concussion clinic.

PubMed

Bock, Suzanne; Grim, Rod; Barron, Todd F; Wagenheim, Andrew; Hu, Yaowen Eliot; Hendell, Matthew; Deitch, John; Deibert, Ellen

2015-11-01

With the increase in knowledge and management of sport-related concussion over the last 15 years, there has been a shift from a grading scale approach to an individualized management approach. As a result, there is an increased need to better understand the factors involved in delayed recovery of concussion. The purpose of this retrospective study was to examine factors that may be associated with recovery from sport-related concussion in student athletes aged 11 to 18 years old. Of the 366 patients who met the inclusion criteria, 361 were included in our analysis. The primary dependent variable included days until athlete was able to return to play (RTP). Independent variables of interest included age, gender, academic performance, comorbid factors, sports, on-field markers, days until initial neurological evaluation, Immediate Post-Concussion Assessment and Cognitive Testing (ImPACT®) scores, acute headache rescue medications, chronic headache medication, sleep medication, and referral to concussion rehabilitation program. Variables associated with longer median RTP were being female (35 days), having a referral to concussion rehabilitation program (53 days), being prescribed acute headache rescue therapy (34 days), and having chronic headache treatment (53 days) (all p < 0.05). Variables associated with shorter RTP were on-field marker of headache (23 days) and evaluation within 1 week of concussion by a concussion specialist (16 days) (Both p < 0.05). This study supports the need for a concussed athlete to have access to a provider trained in concussion management in a timely fashion in order to prevent delayed recovery and return to play.

Development of equations to predict the influence of floor space on average daily gain, average daily feed intake and gain : feed ratio of finishing pigs.

PubMed

Flohr, J R; Dritz, S S; Tokach, M D; Woodworth, J C; DeRouchey, J M; Goodband, R D

2018-05-01

Floor space allowance for pigs has substantial effects on pig growth and welfare. Data from 30 papers examining the influence of floor space allowance on the growth of finishing pigs was used in a meta-analysis to develop alternative prediction equations for average daily gain (ADG), average daily feed intake (ADFI) and gain : feed ratio (G : F). Treatment means were compiled in a database that contained 30 papers for ADG and 28 papers for ADFI and G : F. The predictor variables evaluated were floor space (m2/pig), k (floor space/final BW0.67), Initial BW, Final BW, feed space (pigs per feeder hole), water space (pigs per waterer), group size (pigs per pen), gender, floor type and study length (d). Multivariable general linear mixed model regression equations were used. Floor space treatments within each experiment were the observational and experimental unit. The optimum equations to predict ADG, ADFI and G : F were: ADG, g=337.57+(16 468×k)-(237 350×k 2)-(3.1209×initial BW (kg))+(2.569×final BW (kg))+(71.6918×k×initial BW (kg)); ADFI, g=833.41+(24 785×k)-(388 998×k 2)-(3.0027×initial BW (kg))+(11.246×final BW (kg))+(187.61×k×initial BW (kg)); G : F=predicted ADG/predicted ADFI. Overall, the meta-analysis indicates that BW is an important predictor of ADG and ADFI even after computing the constant coefficient k, which utilizes final BW in its calculation. This suggests including initial and final BW improves the prediction over using k as a predictor alone. In addition, the analysis also indicated that G : F of finishing pigs is influenced by floor space allowance, whereas individual studies have concluded variable results.

Evaluation of Ten Methods for Initializing a Land Surface Model

NASA Technical Reports Server (NTRS)

Rodell, M.; Houser, P. R.; Berg, A. A.; Famiglietti, J. S.

2005-01-01

Land surface models (LSMs) are computer programs, similar to weather and climate prediction models, which simulate the stocks and fluxes of water (including soil moisture, snow, evaporation, and runoff) and energy (including the temperature of and sensible heat released from the soil) after they arrive on the land surface as precipitation and sunlight. It is not currently possible to measure all of the variables of interest everywhere on Earth with sufficient accuracy and space-time resolution. Hence LSMs have been developed to integrate the available observations with our understanding of the physical processes involved, using powerful computers, in order to map these stocks and fluxes as they change in time. The maps are used to improve weather forecasts, support water resources and agricultural applications, and study the Earth"s water cycle and climate variability. NASA"s Global Land Data Assimilation System (GLDAS) project facilitates testing of several different LSMs with a variety of input datasets (e.g., precipitation, plant type).

Early Results from the Lunar Atmosphere and Dust Environment Explorer (LADEE)

NASA Technical Reports Server (NTRS)

Elphic, R. C.; Hine, B.; Delory, G. T.; Mahaffy, Paul; Benna, Mehdi; Horanyi, Mihaly; Colaprete, Anthony; Noble, Sarah

2014-01-01

On 6 September, 2013, a near-perfect launch of the first Minotaur V rocket successfully carried NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) into a high-eccentricity geocentric orbit. After 30 days of phasing, LADEE arrived at the Moon on 6 October, 2013. LADEE's science objectives are twofold: (1) Determine the composition of the lunar atmosphere, investigate processes controlling its distribution and variability, including sources, sinks, and surface interactions; (2) Characterize the lunar exospheric dust environment, measure its spatial and temporal variability, and effects on the lunar atmosphere, if any. After a successful commissioning phase, the three science instruments have made systematic observations of the lunar dust and exospheric environment. These include initial observations of argon, neon and helium exospheres, and their diurnal variations; the lunar micrometeoroid impact ejecta cloud and its variations; spatial and temporal variations of the sodium exosphere; and the search for sunlight extinction caused by dust. LADEE also made observations of the effects of the Chang'e 3 landing on 14 December 2013.

State space approach to mixed boundary value problems.

NASA Technical Reports Server (NTRS)

Chen, C. F.; Chen, M. M.

1973-01-01

A state-space procedure for the formulation and solution of mixed boundary value problems is established. This procedure is a natural extension of the method used in initial value problems; however, certain special theorems and rules must be developed. The scope of the applications of the approach includes beam, arch, and axisymmetric shell problems in structural analysis, boundary layer problems in fluid mechanics, and eigenvalue problems for deformable bodies. Many classical methods in these fields developed by Holzer, Prohl, Myklestad, Thomson, Love-Meissner, and others can be either simplified or unified under new light shed by the state-variable approach. A beam problem is included as an illustration.

Image Display and Manipulation System (IDAMS) program documentation, Appendixes A-D. [including routines, convolution filtering, image expansion, and fast Fourier transformation

NASA Technical Reports Server (NTRS)

Cecil, R. W.; White, R. A.; Szczur, M. R.

1972-01-01

The IDAMS Processor is a package of task routines and support software that performs convolution filtering, image expansion, fast Fourier transformation, and other operations on a digital image tape. A unique task control card for that program, together with any necessary parameter cards, selects each processing technique to be applied to the input image. A variable number of tasks can be selected for execution by including the proper task and parameter cards in the input deck. An executive maintains control of the run; it initiates execution of each task in turn and handles any necessary error processing.

The Increase of Exotic Zoonotic Helminth Infections: The Impact of Urbanization, Climate Change and Globalization.

PubMed

Gordon, Catherine A; McManus, Donald P; Jones, Malcolm K; Gray, Darren J; Gobert, Geoffrey N

2016-01-01

Zoonotic parasitic diseases are increasingly impacting human populations due to the effects of globalization, urbanization and climate change. Here we review the recent literature on the most important helminth zoonoses, including reports of incidence and prevalence. We discuss those helminth diseases which are increasing in endemic areas and consider their geographical spread into new regions within the framework of globalization, urbanization and climate change to determine the effect these variables are having on disease incidence, transmission and the associated challenges presented for public health initiatives, including control and elimination. Copyright © 2016 Elsevier Ltd. All rights reserved.

The SeaFlux Turbulent Flux Dataset Version 1.0 Documentation

NASA Technical Reports Server (NTRS)

Clayson, Carol Anne; Roberts, J. Brent; Bogdanoff, Alec S.

2012-01-01

Under the auspices of the World Climate Research Programme (WCRP) Global Energy and Water cycle EXperiment (GEWEX) Data and Assessment Panel (GDAP), the SeaFlux Project was created to investigate producing a high-resolution satellite-based dataset of surface turbulent fluxes over the global oceans. The most current release of the SeaFlux product is Version 1.0; this represents the initial release of turbulent surface heat fluxes, associated near-surface variables including a diurnally varying sea surface temperature.

Optical Variability and Bottom Classification in Turbid Waters: HyMOM Predictions of the Light Field in Ports and Beneath Ship Hulls

DTIC Science & Technology

2006-09-30

dealing with the bleaching of corals and foraminifera and the photosynthesis of benthic plants. OBJECTIVES The initial objective of this work...of the structural light field around coral heads and other vertical structures should be included in future studies of bleaching of coral and... coral bleaching –Perceptibility problem begun for AUV @2m and @8m above 10m bottom –Higher resolution and higher-speed calculations (e.g. more

A Study of Overhead Rate Behavior at a US Air Force Base in the Context of A-76 Competitions.

DTIC Science & Technology

1999-07-28

was included separately to portray time as an important independent variable. 12 Defense Reform Initiative Report (DoD 1997a), p. 29 . 13 Defense...a threshold of savings that is at least 10 percent of direct personnel costs or $10 million over the performance period. 29 OMB established this...been performing the activity prior to the competition and, 29 The length of the contract is generally considered to be the performance period. Depending

Design of helicopter rotors to noise constraints

NASA Technical Reports Server (NTRS)

Schaeffer, E. G.; Sternfeld, H., Jr.

1978-01-01

Results of the initial phase of a research project to study the design constraints on helicopter noise are presented. These include the calculation of nonimpulsive rotor harmonic and broadband hover noise spectra, over a wide range of rotor design variables and the sensitivity of perceived noise level (PNL) to changes in rotor design parameters. The prediction methodology used correlated well with measured whirl tower data. Application of the predictions to variations in rotor design showed tip speed and thrust as having the most effect on changing PNL.

Theoretical and Experimental Investigation of Heat Conduction in Air, Including Effects of Oxygen Dissociation

NASA Technical Reports Server (NTRS)

Hansen, C. Frederick; Early, Richard A.; Alzofon, Frederick E.; Witteborn, Fred C.

1959-01-01

Solutions are presented for the conduction of beat through a semi-infinite gas medium having a uniform initial temperature and a constant boundary temperature. The coefficients of thermal conductivity and diffusivity are treated as variables, and the solutions are extended to the case of air at temperatures where oxygen dissociation occurs. These solutions are used together with shock-tube measurements to evaluate the integral of thermal conductivity for air as a function of temperature.

Osteogenesis imperfecta and hearing loss--description of three case reports.

PubMed

Pereira da Silva, Ana; Feliciano, Telma; Figueirinhas, Rosário; Almeida E Sousa, Cecília

2013-01-01

Osteogenesis imperfecta is the commonest connective tissue hereditary disease. Its clinical presentation has a wide spectrum of characteristics, which includes skeletal deformities and hearing loss. We describe three case reports of individuals carriers of this disease presenting with different patterns of hearing loss. Hearing loss prevalence and patterns are variable and have no clear relation with genotype. Its assessment at initial evaluation and posterior monitoring is essential to provide the best therapeutic alternatives. Copyright © 2012 Elsevier España, S.L. All rights reserved.

A Bayesian Approach to Identifying Structural Nonlinearity using Free-Decay Response: Application to Damage Detection in Composites

DTIC Science & Technology

2010-03-03

obtainable while for the free-decay problem we simply have to include the initial conditions as random variables to be predicted. A different approach that...important and useful properties of MLEs is that, under regularity conditions , they are asymptotically unbiased and possess the minimum possible...becomes pLðzjh;s2G;MiÞ (i.e. the likelihood is conditional on the specified model). However, in this work we will only consider a single model and drop the

An Analysis of the United States Special Operations Command’s Acquisition Process to Determine Its Compliance with Acquisition Reform Initiatives of the Past Decade

DTIC Science & Technology

1996-12-01

This includes an exemption from publishing the opportunity in the Commerce Business Daily ( CBD ) and elimination of the requirement to hold the...of assigned programs. In discharging this responsibility, thc 990 coor.int-tes his efforts with ether ASN(RDMA) offices, b. TEFlO..M-VAL OPERATIONS...Communications, Computers and Information Systems CA Civil Affairs CAIV Cost as an Independent Variable CBD Commerce Business Daily CBPL Capabilities

Techniques and resources for storm-scale numerical weather prediction

NASA Technical Reports Server (NTRS)

Droegemeier, Kelvin; Grell, Georg; Doyle, James; Soong, Su-Tzai; Skamarock, William; Bacon, David; Staniforth, Andrew; Crook, Andrew; Wilhelmson, Robert

1993-01-01

The topics discussed include the following: multiscale application of the 5th-generation PSU/NCAR mesoscale model, the coupling of nonhydrostatic atmospheric and hydrostatic ocean models for air-sea interaction studies; a numerical simulation of cloud formation over complex topography; adaptive grid simulations of convection; an unstructured grid, nonhydrostatic meso/cloud scale model; efficient mesoscale modeling for multiple scales using variable resolution; initialization of cloud-scale models with Doppler radar data; and making effective use of future computing architectures, networks, and visualization software.

Report of the solar physics panel

NASA Technical Reports Server (NTRS)

Withbroe, George L.; Fisher, Richard R.; Antiochos, Spiro; Brueckner, Guenter; Hoeksema, J. Todd; Hudson, Hugh; Moore, Ronald; Radick, Richard R.; Rottman, Gary; Scherrer, Philip

1991-01-01

Recent accomplishments in solar physics can be grouped by the three regions of the Sun: the solar interior, the surface, and the exterior. The future scientific problems and areas of interest involve: generation of magnetic activity cycle, energy storage and release, solar activity, solar wind and solar interaction. Finally, the report discusses a number of future space mission concepts including: High Energy Solar Physics Mission, Global Solar Mission, Space Exploration Initiative, Solar Probe Mission, Solar Variability Explorer, Janus, as well as solar physics on Space Station Freedom.

Formulation and process factors influencing product quality and in vitro performance of ophthalmic ointments.

PubMed

Xu, Xiaoming; Al-Ghabeish, Manar; Rahman, Ziyaur; Krishnaiah, Yellela S R; Yerlikaya, Firat; Yang, Yang; Manda, Prashanth; Hunt, Robert L; Khan, Mansoor A

2015-09-30

Owing to its unique anatomical and physiological functions, ocular surface presents special challenges for both design and performance evaluation of the ophthalmic ointment drug products formulated with a variety of bases. The current investigation was carried out to understand and identify the appropriate in vitro methods suitable for quality and performance evaluation of ophthalmic ointment, and to study the effect of formulation and process variables on its critical quality attributes (CQA). The evaluated critical formulation variables include API initial size, drug percentage, and mineral oil percentage while the critical process parameters include mixing rate, temperature, time and cooling rate. The investigated quality and performance attributes include drug assay, content uniformity, API particle size in ointment, rheological characteristics, in vitro drug release and in vitro transcorneal drug permeation. Using design of experiments (DoE) as well as a novel principle component analysis approach, five of the quality and performance attributes (API particle size, storage modulus of ointment, high shear viscosity of ointment, in vitro drug release constant and in vitro transcorneal drug permeation rate constant) were found to be highly influenced by the formulation, in particular the strength of API, and to a lesser degree by processing variables. Correlating the ocular physiology with the physicochemical characteristics of acyclovir ophthalmic ointment suggested that in vitro quality metrics could be a valuable predictor of its in vivo performance. Published by Elsevier B.V.

Space vehicle approach velocity judgments under simulated visual space conditions

NASA Technical Reports Server (NTRS)

Haines, Richard F.

1987-01-01

Thirty-five volunteers responded when they first perceived an increase in apparent size of a collimated, 2-D image of an Orbiter vehicle. The test variables of interest included the presence of a fixed angular reticle within the field of view (FOV); three initial Orbiter distances; three constant Orbiter approach velocities corresponding to 1.6, 0.8, and 0.4 percent of the initial distance per second; and two background starfield velocities. It was found that: (1) at each initial range, increasing approach velocity led to a larger distance between the eye and Orbiter image at threshold; (2) including the fixed reticle in the FOV produced a smaller distance between the eye and Orbiter image at threshold; and (3) increasing background star velocity during this judgment led to a smaller distance between the eye and Orbiter image at threshold. The last two findings suggest that other detail within the FOV may compete for available attention which otherwise would be available for judging image expansion; thus, the target has to approach the observer nearer than otherwise if these details were present. These findings are discussed in relation to previous research and possible underlying mechanisms.

Meteorological factors and timing of the initiating event of human parturition

NASA Astrophysics Data System (ADS)

Hirsch, Emmet; Lim, Courtney; Dobrez, Deborah; Adams, Marci G.; Noble, William

2011-03-01

The aim of this study was to determine whether meteorological factors are associated with the timing of either onset of labor with intact membranes or rupture of membranes prior to labor—together referred to as `the initiating event' of parturition. All patients delivering at Evanston Hospital after spontaneous labor or rupture of membranes at ≥20 weeks of gestation over a 6-month period were studied. Logistic regression models of the initiating event of parturition using clinical variables (maternal age, gestational age, parity, multiple gestation and intrauterine infection) with and without the addition of meteorological variables (barometric pressure, temperature and humidity) were compared. A total of 1,088 patients met the inclusion criteria. Gestational age, multiple gestation and chorioamnionitis were associated with timing of initiation of parturition ( P < 0.01). The addition of meteorological to clinical variables generated a statistically significant improvement in prediction of the initiating event; however, the magnitude of this improvement was small (less than 2% difference in receiver-operating characteristic score). These observations held regardless of parity, fetal number and gestational age. Meteorological factors are associated with the timing of parturition, but the magnitude of this association is small.

Analysis and Hindcast Experiments of the 2009 Sudden Stratospheric Warming in WACCMX+DART

NASA Astrophysics Data System (ADS)

Pedatella, N. M.; Liu, H.-L.; Marsh, D. R.; Raeder, K.; Anderson, J. L.; Chau, J. L.; Goncharenko, L. P.; Siddiqui, T. A.

2018-04-01

The ability to perform data assimilation in the Whole Atmosphere Community Climate Model eXtended version (WACCMX) is implemented using the Data Assimilation Research Testbed (DART) ensemble adjustment Kalman filter. Results are presented demonstrating that WACCMX+DART analysis fields reproduce the middle and upper atmosphere variability during the 2009 major sudden stratospheric warming (SSW) event. Compared to specified dynamics WACCMX, which constrains the meteorology by nudging toward an external reanalysis, the large-scale dynamical variability of the stratosphere, mesosphere, and lower thermosphere is improved in WACCMX+DART. This leads to WACCMX+DART better representing the downward transport of chemical species from the mesosphere into the stratosphere following the SSW. WACCMX+DART also reproduces most aspects of the observed variability in ionosphere total electron content and equatorial vertical plasma drift during the SSW. Hindcast experiments initialized on 5, 10, 15, 20, and 25 January are used to assess the middle and upper atmosphere predictability in WACCMX+DART. A SSW, along with the associated middle and upper atmosphere variability, is initially predicted in the hindcast initialized on 15 January, which is ˜10 days prior to the warming. However, it is not until the hindcast initialized on 20 January that a major SSW is forecast to occur. The hindcast experiments reveal that dominant features of the total electron content can be forecasted ˜10-20 days in advance. This demonstrates that whole atmosphere models that properly account for variability in lower atmosphere forcing can potentially extend the ionosphere-thermosphere forecast range.

Treating Hepatitis C in a Ryan White-Funded HIV Clinic: Has the Treatment Uptake Improved in the Interferon-Free Directly Active Antiviral Era?

PubMed

Cope, Rebecca; Glowa, Thomas; Faulds, Samantha; McMahon, Deborah; Prasad, Ramakrishna

2016-02-01

Now that highly efficacious, interferon-free (IFN-free), direct acting antivirals (DAA) for the treatment of hepatitis C (HCV) have closed the gap between treatment and cure, identifying barriers that prevent initiation of treatment is more crucial than ever. This is a retrospective study utilizing Electronic Medical Records and Prior Authorization Records to identify HCV treatment gaps, including predictors for intention-to-treat and treatment initiation in the first 15 months of a Ryan White funded human immunodeficiency virus (HIV)/HCV co-infection clinic. This study included 128 adults ≥ 18 years old with HIV and chronic HCV infection who had visited the treatment center at least once since January 2013. Provider intent-to-treat was used to differentiate patients actively considered for treatment based on documentation kept by a multidisciplinary HCV team. Members of this group who had gone on to initiate treatment were identified. Baseline characteristics were compared. Rates of active treatment consideration and treatment initiation were 30% and 14%, respectively. HCV treatment-naïve individuals were less likely to be considered for treatment [risk ratio (RR) 1.58, 95% confidence interval (CI) 1.07-2.32] and initiate therapy (RR 2.33, 95% CI 0.97-5.60). Advanced liver disease had no significant association. Black race (RR 1.96, 95% CI 0.90-4.25) and Medicaid insurance holders (RR 1.90, 95% CI 0.95-3.82) tended to be less likely to initiate therapy. The availability of IFN-free DAA regimens has yet to increase HCV treatment uptake in our HIV/HCV co-infected population. Barriers to HCV treatment initiation have shifted from medical contraindications to socioeconomic variables.

Breastfeeding initiation in women with gestational diabetes mellitus.

PubMed

Cordero, L; Gabbe, S G; Landon, M B; Nankervis, C A

2013-01-01

In the United States, breastfeeding initiation (BFI) is reported for 75% of all live births; however, little information is available regarding mothers affected by gestational diabetes mellitus (GDM). To examine feeding practices and factors associated with BFI in women with GDM and their infants. A total of 303 GDM (58 late preterm and 245 term) pregnancies were studied. Infant feeding preference was ascertained on admission to labor and delivery. Variables known to influence BFI including maternal age, smoking, obesity, racial and educational characteristics were assessed. On admission 188 women intended to BF, 60 intended to feed formula and 55 were undecided. None of the women who wished to feed formula and 27% of the originally undecided later initiated BF. Regardless of feeding preference 163 (54%) of all mothers initiated BF. Similar BFI rates were found for 176 Class A1 and 127 class A2 women. Logistic regression analysis showed that intention to BF was the most significant predictor of BFI. Factors associated with BFI failure included African American race, lower education, smoking, obesity and admission to NICU. Following delivery 264 (87%) infants received well baby care while 39 (13%) were admitted to the NICU. Among 188 women who intended to BF, BFI involved 81% of 160 infants receiving well baby care and 61% of the 28 admitted to the NICU. More than half of women with GDM, who intended to BF, initiated BF. BFI failure remains associated with race, lower education level, smoking, obesity, preference for formula feeding and admission to NICU.

An investigation of bioecological influences associated with first use of methamphetamine in a rural state.

PubMed

Bowen, Anne; Moring, John; Williams, Mark; Hopper, Glenna; Daniel, Candice

2012-01-01

Methamphetamine (MA) addiction is a significant problem in rural areas of the United States. Yet, little theoretically driven formative research has been conducted on the interactions of factors influencing initiation. The study was guided by Bronfenbrenner's bioecological model. Eighty-three MA users participated in an interview. Quantitative data included sociodemographic characteristics, drug use history, and psychosocial functioning. Semistructured interviews examined MA use histories with a focus on initiation. Transcripts of the interviews were coded for 5 themes related to Bronfenbrenner's influences including individual motivation, family, peers, work or school, or community as factors influencing initiation of MA use. Five dummy variables representing the presence or absence of a mention of Bronfenbrenner's 5 influences were created from the qualitative codes and entered into a hierarchical cluster analysis. The analyses revealed 4 distinct clusters: (1) predominantly female, influenced by peers and individual curiosity, (2) predominantly female, youngest age of first use, influenced by a family culture of drug use, (3) predominantly male, older age at first use, influenced by work settings and family co-workers, and (4) predominantly male, older age at first use, in the school context with a desire to increase intimacy. Bronfenbrenner's bioecological model was useful for classifying initiating influences and grouping individuals based on different combinations of influences. Identifying combinations of initiating factors such as work and community may facilitate tailoring of prevention programs, which may maximize efficacy and cost-effectiveness. © 2011 National Rural Health Association.

Students' Misconceptions about Random Variables

ERIC Educational Resources Information Center

Kachapova, Farida; Kachapov, Ilias

2012-01-01

This article describes some misconceptions about random variables and related counter-examples, and makes suggestions about teaching initial topics on random variables in general form instead of doing it separately for discrete and continuous cases. The focus is on post-calculus probability courses. (Contains 2 figures.)

The Role of Microtexture on Fatigue Lifetime Variability and Crack Initiation Mechanisms (Preprint)

DTIC Science & Technology

2011-10-01

October 2011 4 . TITLE AND SUBTITLE THE ROLE OF MICROTEXTURE OF FATIGUE LIFETIME VARIABILITY AND CRACK INITIATION MECHANISMS (PREPRINT) 5a...CONTRACT NUMBER In-house 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 62102F 6 . AUTHOR(S) Christopher J. Szczepanski (Universal Technology...Preprint journal article to be submitted to Titanium 2011 World Conference. This document contains color. 14. ABSTRACT Commercial titanium alloys

A Multi-Model Assessment for the 2006 and 2010 Simulations under the Air Quality Model Evaluation International Initiative (AQMEII) Phase 2 over North America: Part II. Evaluation of Column Variable Predictions Using Satellite Data

EPA Science Inventory

Within the context of the Air Quality Model Evaluation International Initiative phase 2 (AQMEII2) project, this part II paper performs a multi-model assessment of major column abundances of gases, radiation, aerosol, and cloud variables for 2006 and 2010 simulations with three on...

Progression paths in children's problem solving: The influence of dynamic testing, initial variability, and working memory.

PubMed

Resing, Wilma C M; Bakker, Merel; Pronk, Christine M E; Elliott, Julian G

2017-01-01

The current study investigated developmental trajectories of analogical reasoning performance of 104 7- and 8-year-old children. We employed a microgenetic research method and multilevel analysis to examine the influence of several background variables and experimental treatment on the children's developmental trajectories. Our participants were divided into two treatment groups: repeated practice alone and repeated practice with training. Each child received an initial working memory assessment and was subsequently asked to solve figural analogies on each of several sessions. We examined children's analogical problem-solving behavior and their subsequent verbal accounts of their employed solving processes. We also investigated the influence of verbal and visual-spatial working memory capacity and initial variability in strategy use on analogical reasoning development. Results indicated that children in both treatment groups improved but that gains were greater for those who had received training. Training also reduced the influence of children's initial variability in the use of analogical strategies with the degree of improvement in reasoning largely unrelated to working memory capacity. Findings from this study demonstrate the value of a microgenetic research method and the use of multilevel analysis to examine inter- and intra-individual change in problem-solving processes. Copyright © 2016 Elsevier Inc. All rights reserved.

Step-to-step spatiotemporal variables and ground reaction forces of intra-individual fastest sprinting in a single session.

PubMed

Nagahara, Ryu; Mizutani, Mirai; Matsuo, Akifumi; Kanehisa, Hiroaki; Fukunaga, Tetsuo

2018-06-01

We aimed to investigate the step-to-step spatiotemporal variables and ground reaction forces during the acceleration phase for characterising intra-individual fastest sprinting within a single session. Step-to-step spatiotemporal variables and ground reaction forces produced by 15 male athletes were measured over a 50-m distance during repeated (three to five) 60-m sprints using a long force platform system. Differences in measured variables between the fastest and slowest trials were examined at each step until the 22nd step using a magnitude-based inferences approach. There were possibly-most likely higher running speed and step frequency (2nd to 22nd steps) and shorter support time (all steps) in the fastest trial than in the slowest trial. Moreover, for the fastest trial there were likely-very likely greater mean propulsive force during the initial four steps and possibly-very likely larger mean net anterior-posterior force until the 17th step. The current results demonstrate that better sprinting performance within a single session is probably achieved by 1) a high step frequency (except the initial step) with short support time at all steps, 2) exerting a greater mean propulsive force during initial acceleration, and 3) producing a greater mean net anterior-posterior force during initial and middle acceleration.

Random Initialisation of the Spectral Variables: an Alternate Approach for Initiating Multivariate Curve Resolution Alternating Least Square (MCR-ALS) Analysis.

PubMed

Kumar, Keshav

2017-11-01

Multivariate curve resolution alternating least square (MCR-ALS) analysis is the most commonly used curve resolution technique. The MCR-ALS model is fitted using the alternate least square (ALS) algorithm that needs initialisation of either contribution profiles or spectral profiles of each of the factor. The contribution profiles can be initialised using the evolve factor analysis; however, in principle, this approach requires that data must belong to the sequential process. The initialisation of the spectral profiles are usually carried out using the pure variable approach such as SIMPLISMA algorithm, this approach demands that each factor must have the pure variables in the data sets. Despite these limitations, the existing approaches have been quite a successful for initiating the MCR-ALS analysis. However, the present work proposes an alternate approach for the initialisation of the spectral variables by generating the random variables in the limits spanned by the maxima and minima of each spectral variable of the data set. The proposed approach does not require that there must be pure variables for each component of the multicomponent system or the concentration direction must follow the sequential process. The proposed approach is successfully validated using the excitation-emission matrix fluorescence data sets acquired for certain fluorophores with significant spectral overlap. The calculated contribution and spectral profiles of these fluorophores are found to correlate well with the experimental results. In summary, the present work proposes an alternate way to initiate the MCR-ALS analysis.

Initial 12-h operative fluid volume is an independent risk factor for pleural effusion after hepatectomy.

PubMed

Cheng, Xiang; Wu, Jia-Wei; Sun, Ping; Song, Zi-Fang; Zheng, Qi-Chang

2016-12-01

Pleural effusion after hepatectomy is associated with significant morbidity and prolonged hospital stays. Several studies have addressed the risk factors for postoperative pleural effusion. However, there are no researches concerning the role of the initial 12-h operative fluid volume. The aim of this study was to evaluate whether the initial 12-h operative fluid volume during liver resection is an independent risk factor for pleural effusion after hepatectomy. In this study, we retrospectively analyzed clinical data of 470 patients consecutively undergoing elective hepatectomy between January 2011 and December 2012. We prospectively collected and retrospectively analyzed baseline and clinical data, including preoperative, intraoperative, and postoperative variables. Univariate and multivariate analyses were carried out to identify whether the initial 12-h operative fluid volume was an independent risk factor for pleural effusion after hepatectomy. The multivariate analysis identified 2 independent risk factors for pleural effusion: operative time [odds ratio (OR)=10.2] and initial 12-h operative fluid volume (OR=1.0003). Threshold effect analyses revealed that the initial 12 h operative fluid volume was positively correlated with the incidence of pleural effusion when the initial 12-h operative fluid volume exceeded 4636 mL. We conclude that the initial 12-h operative fluid volume during liver resection and operative time are independent risk factors for pleural effusion after hepatectomy. Perioperative intravenous fluids should be restricted properly.

Water quality parameters of harbors of Charlotte Amalie, St. Thomas, Virgin Islands: Acquisition of in situ water data, intercorrelation of selected water parameters, and initial correlation of these in situ biological, chemical and physical data with ERTS-1 bulk CCT MSS band 5 data

NASA Technical Reports Server (NTRS)

Coulbourn, W. C.; Olsen, D. A. (Principal Investigator)

1973-01-01

The author has identified the following significant results. Remote sensing by the ERTS-1 satellite was compared with selected water quality parameters including pH, salinity, conductivity, dissolved oxygen, water depth, water temperature, turbidity, plankton concentration, current variables, chlorophylla, total carotenoids, and species diversity of the benthic community. Strong correlation between turbidity and MSS-sensed radiance was recorded and less strong correlations between the two plankton pigments and radiance. Turbidity and benthic species diversity were highly correlated furnishing an inferential tie between an easily sensed water quality variable and a sensitive indicator of average water quality conditions.

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

Dayman, Ken J; Ade, Brian J; Weber, Charles F

High-dimensional, nonlinear function estimation using large datasets is a current area of interest in the machine learning community, and applications may be found throughout the analytical sciences, where ever-growing datasets are making more information available to the analyst. In this paper, we leverage the existing relevance vector machine, a sparse Bayesian version of the well-studied support vector machine, and expand the method to include integrated feature selection and automatic function shaping. These innovations produce an algorithm that is able to distinguish variables that are useful for making predictions of a response from variables that are unrelated or confusing. We testmore » the technology using synthetic data, conduct initial performance studies, and develop a model capable of making position-independent predictions of the coreaveraged burnup using a single specimen drawn randomly from a nuclear reactor core.« less

Clinical predictors of vestibulo-ocular dysfunction in pediatric sports-related concussion.

PubMed

Ellis, Michael J; Cordingley, Dean M; Vis, Sara; Reimer, Karen M; Leiter, Jeff; Russell, Kelly

2017-01-01

OBJECTIVE There were 2 objectives of this study. The first objective was to identify clinical variables associated with vestibulo-ocular dysfunction (VOD) detected at initial consultation among pediatric patients with acute sports-related concussion (SRC) and postconcussion syndrome (PCS). The second objective was to reexamine the prevalence of VOD in this clinical cohort and evaluate the effect of VOD on length of recovery and the development of PCS. METHODS A retrospective review was conducted for all patients with acute SRC and PCS who were evaluated at a pediatric multidisciplinary concussion program from September 2013 to May 2015. Acute SRS was defined as presenting < 30 days postinjury, and PCS was defined according to the International Classification of Diseases, 10th Revision criteria and included being symptomatic 30 days or longer postinjury. The initial assessment included clinical history and physical examination performed by 1 neurosurgeon. Patients were assessed for VOD, defined as the presence of more than 1 subjective vestibular and oculomotor complaint (dizziness, diplopia, blurred vision, etc.) and more than 1 objective physical examination finding (abnormal near point of convergence, smooth pursuits, saccades, or vestibulo-ocular reflex testing). Poisson regression analysis was used to identify factors that increased the risk of VOD at initial presentation and the development of PCS. RESULTS Three hundred ninety-nine children, including 306 patients with acute SRC and 93 with PCS, were included. Of these patients, 30.1% of those with acute SRC (65.0% male, mean age 13.9 years) and 43.0% of those with PCS (41.9% male, mean age 15.4 years) met the criteria for VOD at initial consultation. Independent predictors of VOD at initial consultation included female sex, preinjury history of depression, posttraumatic amnesia, and presence of dizziness, blurred vision, or difficulty focusing at the time of injury. Independent predictors of PCS among patients with acute SRC included the presence of VOD at initial consultation, preinjury history of depression, and posttraumatic amnesia at the time of injury. CONCLUSIONS This study identified important potential risk factors for the development of VOD following pediatric SRC. These results provide confirmatory evidence that VOD at initial consultation is associated with prolonged recovery and is an independent predictor for the development of PCS. Future studies examining clinical prediction rules in pediatric concussion should include VOD. Additional research is needed to elucidate the natural history of VOD following SRC and establish evidence-based indications for targeted vestibular rehabilitation.

Framework for the rapid optimization of soluble protein expression in Escherichia coli combining microscale experiments and statistical experimental design.

PubMed

Islam, R S; Tisi, D; Levy, M S; Lye, G J

2007-01-01

A major bottleneck in drug discovery is the production of soluble human recombinant protein in sufficient quantities for analysis. This problem is compounded by the complex relationship between protein yield and the large number of variables which affect it. Here, we describe a generic framework for the rapid identification and optimization of factors affecting soluble protein yield in microwell plate fermentations as a prelude to the predictive and reliable scaleup of optimized culture conditions. Recombinant expression of firefly luciferase in Escherichia coli was used as a model system. Two rounds of statistical design of experiments (DoE) were employed to first screen (D-optimal design) and then optimize (central composite face design) the yield of soluble protein. Biological variables from the initial screening experiments included medium type and growth and induction conditions. To provide insight into the impact of the engineering environment on cell growth and expression, plate geometry, shaking speed, and liquid fill volume were included as factors since these strongly influence oxygen transfer into the wells. Compared to standard reference conditions, both the screening and optimization designs gave up to 3-fold increases in the soluble protein yield, i.e., a 9-fold increase overall. In general the highest protein yields were obtained when cells were induced at a relatively low biomass concentration and then allowed to grow slowly up to a high final biomass concentration, >8 g.L-1. Consideration and analysis of the model results showed 6 of the original 10 variables to be important at the screening stage and 3 after optimization. The latter included the microwell plate shaking speeds pre- and postinduction, indicating the importance of oxygen transfer into the microwells and identifying this as a critical parameter for subsequent scale translation studies. The optimization process, also known as response surface methodology (RSM), predicted there to be a distinct optimum set of conditions for protein expression which could be verified experimentally. This work provides a generic approach to protein expression optimization in which both biological and engineering variables are investigated from the initial screening stage. The application of DoE reduces the total number of experiments needed to be performed, while experimentation at the microwell scale increases experimental throughput and reduces cost.

Report on Status of Shipment of High Fluence Austenitic Steel Samples for Characterization and Stress Corrosion Crack Testing

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

Clark, Scarlett R.; Leonard, Keith J.

The goal of the Mechanisms of Irradiation Assisted Stress Corrosion Cracking (IASCC) task in the LWRS Program is to conduct experimental research into understanding how multiple variables influence the crack initiation and crack growth in materials subjected to stress under corrosive conditions. This includes understanding the influences of alloy composition, radiation condition, water chemistry and metallurgical starting condition (i.e., previous cold work or heat treatments and the resulting microstructure) has on the behavior of materials. Testing involves crack initiation and growth testing on irradiated specimens of single-variable alloys in simulated Light Water Reactor (LWR) environments, tensile testing, hardness testing, microstructuralmore » and microchemical analysis, and detailed efforts to characterize localized deformation. Combined, these single-variable experiments will provide mechanistic understanding that can be used to identify key operational variables to mitigate or control IASCC, optimize inspection and maintenance schedules to the most susceptible materials/locations, and, in the long-term, design IASCC-resistant materials. In support of this research, efforts are currently underway to arrange shipment of “free” high fluence austenitic alloys available through Électricité de France (EDF) for post irradiation testing at the Oak Ridge National Laboratory (ORNL) and IASCC testing at the University of Michigan. These high fluence materials range in damage values from 45 to 125 displacements per atom (dpa). The samples identified for transport to the United States, which include nine, no-cost, 304, 308 and 316 tensile bars, were relocated from the Research Institute of Atomic Reactors (RIAR) in Dimitrovgrad, Ulyanovsk Oblast, Russia, and received at the Halden Reactor in Halden, Norway, on August 23, 2016. ORNL has been notified that a significant amount of work is required to prepare the samples for further shipment to Oak Ridge, Tennessee. The preliminary work for sample shipment between Halden and Oak Ridge includes fabrication of an inner cask sample container, decontamination and preparation of a Type A container, preparation of new activity calculations, all necessary paperwork, and handling. ORNL will continue to work to track progress of sample preparation and shipment status, and to work toward an agreement that covers material shipping costs between the Halden Reactor and the Oak Ridge National Laboratory.« less

A new approach in space-time analysis of multivariate hydrological data: Application to Brazil's Nordeste region rainfall

NASA Astrophysics Data System (ADS)

Sicard, Emeline; Sabatier, Robert; Niel, HéLèNe; Cadier, Eric

2002-12-01

The objective of this paper is to implement an original method for spatial and multivariate data, combining a method of three-way array analysis (STATIS) with geostatistical tools. The variables of interest are the monthly amounts of rainfall in the Nordeste region of Brazil, recorded from 1937 to 1975. The principle of the technique is the calculation of a linear combination of the initial variables, containing a large part of the initial variability and taking into account the spatial dependencies. It is a promising method that is able to analyze triple variability: spatial, seasonal, and interannual. In our case, the first component obtained discriminates a group of rain gauges, corresponding approximately to the Agreste, from all the others. The monthly variables of July and August strongly influence this separation. Furthermore, an annual study brings out the stability of the spatial structure of components calculated for each year.

Significant Pre-Accession Factors Predicting Success or Failure During a Marine Corps Officer’s Initial Service Obligation

DTIC Science & Technology

2015-12-01

WAIVERS ..............................................................................................49  APPENDIX C. DESCRIPTIVE STATISTICS ... Statistics of Dependent Variables. .............................................23  Table 6.  Summary Statistics of Academics Variables...24  Table 7.  Summary Statistics of Application Variables ............................................25  Table 8

Systematic Review of Cerebral Palsy Registries/Surveillance Groups: Relationships between Registry Characteristics and Knowledge Dissemination

PubMed Central

Hurley, Donna S; Sukal-Moulton, Theresa; Gaebler-Spira, Deborah; Krosschell, Kristin J; Pavone, Larissa; Mutlu, Akmer; Dewald, Julius PA; Msall, Michael E

2016-01-01

The aims of this study were to provide a comprehensive summary of the body of research disseminated by Cerebral Palsy (CP) registries and surveillance programs from January 2009 through May 2014 in order to describe the influence their results have on our overall understanding of CP. Secondly, registries/surveillance programs and the work they produced were evaluated and grouped using standardized definitions and classification systems. Method A systematic review search in PubMed, CINAH and Embase for original articles published from 1 January 2009 to 20 May 2014 originating from or supported by population based CP registries and surveillance programs or population based national registries including CP were included. Articles were grouped by 2009 World CP Registry Congress aim, registry/surveillance program classification, geographical region, and the International Classification of Function, Disability and Health (ICF) domain. Registry variables were assessed using the ICF-CY classification. Results Literature searches returned 177 articles meeting inclusion criteria. The majority (69%) of registry/surveillance program productivity was related to contributions as a Resource for CP Research. Prevention (23%) and Surveillance (22%) articles were other areas of achievement, but fewer articles were published in the areas of Planning (17%) and Raising the Profile of CP (2%). There was a range of registry/surveillance program classifications contributing to this productivity, and representation from multiple areas of the globe, although most of the articles originated in Europe, Australia, and Canada. The domains of the ICF that were primarily covered included body structures and function at the early stages of life. Encouragingly, a variety of CP registry/surveillance program initiatives included additional ICF domains of participation and environmental and personal factors. Interpretation CP registries and surveillance programs, including novel non-traditional ones, have significantly contributed to the understanding of how CP affects individuals, families and society. Moving forward, the global CP registry/surveillance program community should continue to strive for uniformity in CP definitions, variables collected and consistency with international initiatives like the ICF so that databases can be consolidated for research use. Adaptation to new technologies can improve access, reduce cost and facilitate information transfer between registrants, researchers and registries/surveillance programs. Finally, increased efforts in documenting variables of individuals with CP into adulthood should be made in order to expand our understanding of CP across the lifespan. PMID:27790626

Quality indicators in inflammatory bowel disease.

PubMed

Berry, Sameer K; Melmed, Gil Y

2018-01-01

Inflammatory bowel disease (IBD), which includes Crohn's disease and ulcerative colitis, is a chronic, debilitating, and expensive condition affecting millions of people globally. There is significant variation in the quality of care for patients with IBD across North America, Europe, and Asia; this variation suggests poor quality of care due to overuse, underuse, or misuse of health services and disparity of outcomes. Several initiatives have been developed to reduce variation in care delivery and improve processes of care, patient outcomes, and reduced healthcare costs. These initiatives include the development of quality indicator sets to standardize care across organizations, and learning health systems to enable data sharing between doctors and patients, and sharing of best practices among providers. These programs have been variably successful in improving patient outcomes and reducing healthcare utilization. Further studies are needed to demonstrate the long-term impact and applicability of these efforts in different geographic areas around the world, as regional variations in patient populations, societal preferences, and costs should inform local quality improvement efforts.

Seasonal Drought Prediction: Advances, Challenges, and Future Prospects

NASA Astrophysics Data System (ADS)

Hao, Zengchao; Singh, Vijay P.; Xia, Youlong

2018-03-01

Drought prediction is of critical importance to early warning for drought managements. This review provides a synthesis of drought prediction based on statistical, dynamical, and hybrid methods. Statistical drought prediction is achieved by modeling the relationship between drought indices of interest and a suite of potential predictors, including large-scale climate indices, local climate variables, and land initial conditions. Dynamical meteorological drought prediction relies on seasonal climate forecast from general circulation models (GCMs), which can be employed to drive hydrological models for agricultural and hydrological drought prediction with the predictability determined by both climate forcings and initial conditions. Challenges still exist in drought prediction at long lead time and under a changing environment resulting from natural and anthropogenic factors. Future research prospects to improve drought prediction include, but are not limited to, high-quality data assimilation, improved model development with key processes related to drought occurrence, optimal ensemble forecast to select or weight ensembles, and hybrid drought prediction to merge statistical and dynamical forecasts.

Porting Initiation and Failure into Linked CHEETAH

NASA Astrophysics Data System (ADS)

Souers, Clark; Vitello, Peter

2007-06-01

Linked CHEETAH is a thermo-chemical code coupled to a 2-D hydrocode. Initially, a quadratic-pressure dependent kinetic rate was used, which worked well in modeling prompt detonation of explosives of large size, but does not work on other aspects of explosive behavior. The variable-pressure Tarantula reactive flow rate model was developed with JWL++ in order to also describe failure and initiation, and we have moved this model into Linked CHEETAH. The model works by turning on only above a pressure threshold, where a slow turn-on creates initiation. At a higher pressure, the rate suddenly leaps to a large value over a small pressure range. A slowly failing cylinder will see a rapidly declining rate, which pushes it quickly into failure. At a high pressure, the detonation rate is constant. A sequential validation procedure is used, which includes metal-confined cylinders, rate-sticks, corner-turning, initiation and threshold, gap tests and air gaps. The size (diameter) effect is central to the calibration. This work was performed under the auspices of the U.S. Department of Energy by the University of California Lawrence Livermore National Laboratory under contract No. W-7405-Eng-48.

Gestational Age at First Antenatal Care Visit in Malawi.

PubMed

Mkandawire, Paul

2015-11-01

This paper examines the gestational age at first antenatal care (ANC) visit and factors associated with timely initiation of ANC in Malawi in a context where maternal and child health services are generally provided for free. Lognormal survival models are applied to Demographic and Health Survey data from a nationally representative sample of women (n = 13,588) of child-bearing age. The findings of this study show that less than 30 % of pregnant women initiate ANC within the World Health Organization recommended gestational timeframe of 16 weeks or earlier. The hazard analysis shows a gradient in the initiation of ANC by maternal education level, with least educated mothers most likely to delay their first ANC visit. However, after adjusting for variables capturing intimate partner violence in the multivariate models, the effect of maternal education attenuated and lost statistical significance. Other significant predictors of gestational age at first ANC include media exposure, perceived distance from health facility, age, and birth order. The findings of the study link domestic violence directly with the gestational age at which mothers initiate ANC, suggesting that gender-based violence may operate through delayed initiation of ANC to undermine maternal and child health outcomes.

Common Variable Immunodeficiency (CVID)

MedlinePlus

... Award Negotiation & Initial Award After Award Foreign Grants Management Getting Your Initial International Award Actions You Can Take as the Project Leader on a Foreign Grant Subawards for Foreign ...

The role of social and cognitive processes in the relationship between fear network and psychological distress among parents of children undergoing hematopoietic stem cell transplantation.

PubMed

Virtue, Shannon Myers; Manne, Sharon; Mee, Laura; Bartell, Abraham; Sands, Stephen; Ohman-Strickland, Pamela; Gajda, Tina Marie

2014-09-01

The current study examined whether cognitive and social processing variables mediated the relationship between fear network and depression among parents of children undergoing hematopoietic stem cell transplant (HSCT). Parents whose children were initiating HSCT (N = 179) completed survey measures including fear network, Beck Depression Inventory, cognitive processing variables (positive reappraisal and self-blame) and social processing variables (emotional support and holding back from sharing concerns). Fear network was positively correlated with depression (p < .001). Self-blame and holding back emerged as individual partial mediators in the relationship between fear network and depression. Together they accounted for 34.3% of the variance in the relationship between fear network and depression. Positive reappraisal and emotional support did not have significant mediating effects. Social and cognitive processes, specifically self-blame and holding back from sharing concerns, play a negative role in parents' psychological adaptation to fears surrounding a child's HSCT.

The Role of Social and Cognitive Processes in the Relationship between Fear Network and Psychological Distress among Parents of Children Undergoing Hematopoietic Stem Cell Transplantation

PubMed Central

Virtue, Shannon Myers; Manne, Sharon; Mee, Laura; Bartell, Abraham; Sands, Stephen; Ohman-Strickland, Pamela; Gajda, Tina Marie

2014-01-01

The current study examined whether cognitive and social processing variables mediated the relationship between fear network and depression among parents of children undergoing hematopoietic stem cell transplant (HSCT). Parents whose children were initiating HSCT (N = 179) completed survey measures including fear network, Beck Depression Inventory (BDI), cognitive processing variables (positive reappraisal and self-blame) and social processing variables (emotional support and holding back from sharing concerns). Fear network was positively correlated with depression (p < .001). Self-blame and holding back emerged as individual partial mediators in the relationship between fear network and depression. Together they accounted for 34.3% of the variance in the relationship between fear network and depression. Positive reappraisal and emotional support did not have significant mediating effects. Social and cognitive processes, specifically self-blame and holding back from sharing concerns, play a negative role in parents’ psychological adaptation to fears surrounding a child’s HSCT. PMID:25081956

Initial sociometric impressions of attention-deficit hyperactivity disorder and comparison boys: predictions from social behaviors and from nonbehavioral variables.

PubMed

Erhardt, Drew; Hinshaw, Stephen P

1994-08-01

This study systematically compared the influence of naturalistic social behaviors and nonbehavioral variables on the development of peer status in 49 previously unfamiliar boys, aged 6-12 years, who attended a summer research program. Twenty-five boys with attention-deficit hyperactivity disorder (ADHD) and 24 comparison boys participated. Physical attractiveness, motor competence, intelligence, and academic achievement constituted the nonbehavioral variables; social behaviors included noncompliance, aggression, prosocial actions, and isolation, measured by live observations of classroom and playground interactions. As early as the first day of interaction, ADHD and comparison boys displayed clear differences in social behaviors, and the ADHD youngsters were overwhelmingly rejected. Whereas prosocial behavior independently predicted friendship ratings during the first week, the magnitude of prediction was small. In contrast, the boys' aggression (or noncompliance) strongly predicted negative nominations, even with nonbehavioral factors, group status (ADHD versus comparison), and other social behaviors controlled statistically. Implications for understanding and remediating negative peer reputations are discussed.

Evolution of the Orszag-Tang vortex system in a compressible medium. II - Supersonic flow

NASA Technical Reports Server (NTRS)

Picone, J. Michael; Dahlburg, Russell B.

1991-01-01

A study is presented on the effect of embedded supersonic flows and the resulting emerging shock waves on phenomena associated with MHD turbulence, including reconnection, the formation of current sheets and vortex structures, and the evolution of spatial and temporal correlations among physical variables. A two-dimensional model problem, the Orszag-Tang (1979) vortex system, is chosen, which involves decay from nonrandom initial conditions. The system is doubly periodic, and the initial conditions consist of single-mode solenoidal velocity and magnetic fields, each containing X points and O points. The initial mass density is flat, and the initial pressure fluctuations are incompressible, balancing the local forces for a magnetofluid of unit mass density. Results on the evolution of the local structure of the flow field, the global properties of the system, and spectral correlations are presented. The important dynamical properties and observational consequences of embedded supersonic regions and emerging shocks in the Orszag-Tang model of an MHD system undergoing reconnection are discussed. Conclusions are drawn regarding the effects of local supersonic regions on MHD turbulence.

Lessons learned from the U.S. Geological Survey abandoned mine lands initiative: 1997-2002

USGS Publications Warehouse

Kimball, Briant A.; Church, Stan E.; Besser, John M.

2006-01-01

Growth of the United States has been facilitated, in part, by hard-rock mining in the Rocky Mountains. Abandoned and inactive mines cause many significant environmental concerns in hundreds of watersheds. Those who have responsibility to address these environmental concerns must have a basic level of scientific information about mining and mine wastes in a watershed prior to initiating remediation activities. To demonstrate what information is needed and how to obtain that information, the U.S. Geological Survey implemented the Abandoned Mine Lands (AML) Initiative from 1997 to 2002 with demonstration studies in the Boulder River watershed in Montana and the Animas River watershed in Colorado. The AML Initiative included collection and analysis of geologic, hydrologic, geochemical, geophysical, and biological data. The synergy of this interdisciplinary analysis produced a perspective of the environmental concerns that could not have come from a single discipline. Two examples of these perspectives include (1) the combination of hydrological tracer techniques, structural geology, and geophysics help to understand the spatial distribution of loading to the streams in a way that cannot be evaluated by monitoring at a catchment outlet, and (2) the combination of toxicology and hydrology combine to illustrate that seasonal variability of toxicity conditions occurs. Lessons have been learned by listening to and collaborating with land-management agencies to understand their needs and by applying interdisciplinary methods to answer their questions.

Impacts of climate on shrubland fuels and fire behavior in the Owyhee Basin, Idaho

NASA Astrophysics Data System (ADS)

Vogelmann, J. E.; Shi, H.; Hawbaker, T.; Li, Z.

2013-12-01

There is evidence that wildland fire is increasing as a function of global change. However, fire activity is spatially, temporally and ecologically variable across the globe, and our understanding of fire risk and behavior in many ecosystems is limited. After a series of severe fire seasons that occurred during the late 1990's in the western United States, the LANDFIRE program was developed with the goals of providing the fire community with objective spatial fuel data for assessing wildland fire risk. Even with access to the data provided by LANDFIRE, assessing fire behavior in shrublands in sagebrush-dominated ecosystems of the western United States has proven especially problematic, in part due to the complex nature of the vegetation, the variable influence of understory vegetation including invasive species (e.g. cheatgrass), and prior fire history events. Climate is undoubtedly playing a major role, affecting the intra- and inter-annual variability in vegetation conditions, which in turn impacts fire behavior. In order to further our understanding of climate-vegetation-fire interactions in shrublands, we initiated a study in the Owyhee Basin, which is located in southwestern Idaho and adjacent Nevada. Our goals include: (1) assessing the relationship between climate and vegetation condition, (2) quantifying the range of temporal variability in grassland and shrubland fuel loads, (3) identifying methods to operationally map the variability in fuel loads, and (4) assessing how the variability in fuel loads affect fire spread simulations. To address these goals, we are using a wide variety of geospatial data, including remotely sensed time-series data sets derived from MODIS and Landsat, and climate data from DAYMET and PRISM. Remotely-sensed information is used to characterize climate-induced temporal variability in primary productivity in the Basin, where fire spread can be extensive after senescence when dry vegetation is added to dead fuel loads. Gridded climate data indicate that this area has become warmer and dryer over the previous three decades. We have also observed that fires are especially prevalent in areas that have high Normalized Difference Vegetation Index (NDVI) values in the spring, followed by low NDVI in the summer. At present we are concentrating on the temporally rich MODIS data to map spatial and temporal variability in live fuel loads. To translate NDVI to biomass, we are scaling the range of biomass values using data from the literature. We assume that departure from maximum NDVI, typically occurring during spring, to NDVI values later in the season are related to the proportion of live biomass transferred to dead biomass, which burns more readily than green biomass. Using the FARSITE fire spread model, our initial simulations show that the conversion from live herbaceous fuel to dead fuel increases the burn area by 30% compared with using default static fuel parameters. This indicates that current fuel models underestimate fire spread and areas that could potentially burn. Our study also indicates that a combined remote sensing product with good temporal resolution (MODIS) and spatial resolution (Landsat) is necessary to provide accurate information on the fuel dynamics in shrublands.

Academic Procrastination and Goal Accomplishment: A Combined Experimental and Individual Differences Investigation

PubMed Central

Gustavson, Daniel E.; Miyake, Akira

2017-01-01

This study examined the relationship between academic procrastination and goal accomplishment in two novel ways. First, we experimentally tested whether undergraduate students (N = 177) could reduce their academic procrastination over a course of three weeks after performing goal-related exercises to set so-called SMART goals and/or to prepare those students with specific strategies to resist their temptations (forming implementation intentions). Second, we conducted systematic regression analyses to examine whether academic procrastination at baseline uniquely predicts later goal-related outcomes, controlling for various correlated variables, including personality traits (e.g., impulsivity), motivational factors (e.g., motivation for the generated goals), and situational factors (e.g., memory for the goals). Results indicated that neither the SMART-goal nor implementation-intention intervention significantly reduced academic procrastination in the three-week interval, even when relevant moderating variables were examined. Initial levels of academic procrastination, however, were predictive of the success of accomplishing the goals generated during the initial exercises, above and beyond a wide range of other candidate correlates. These results provided new correlational evidence for the association between academic procrastination and goal accomplishment, but suggest a need for further research to understand what interventions are effective at reducing academic procrastination. PMID:28943742

Academic Procrastination and Goal Accomplishment: A Combined Experimental and Individual Differences Investigation.

PubMed

Gustavson, Daniel E; Miyake, Akira

2017-02-01

This study examined the relationship between academic procrastination and goal accomplishment in two novel ways. First, we experimentally tested whether undergraduate students ( N = 177) could reduce their academic procrastination over a course of three weeks after performing goal-related exercises to set so-called SMART goals and/or to prepare those students with specific strategies to resist their temptations (forming implementation intentions). Second, we conducted systematic regression analyses to examine whether academic procrastination at baseline uniquely predicts later goal-related outcomes, controlling for various correlated variables, including personality traits (e.g., impulsivity), motivational factors (e.g., motivation for the generated goals), and situational factors (e.g., memory for the goals). Results indicated that neither the SMART-goal nor implementation-intention intervention significantly reduced academic procrastination in the three-week interval, even when relevant moderating variables were examined. Initial levels of academic procrastination, however, were predictive of the success of accomplishing the goals generated during the initial exercises, above and beyond a wide range of other candidate correlates. These results provided new correlational evidence for the association between academic procrastination and goal accomplishment, but suggest a need for further research to understand what interventions are effective at reducing academic procrastination.

Potential determinants of efficacy of mirror therapy in stroke patients--A pilot study.

PubMed

Brunetti, Maddalena; Morkisch, Nadine; Fritzsch, Claire; Mehnert, Jan; Steinbrink, Jens; Niedeggen, Michael; Dohle, Christian

2015-01-01

Mirror therapy (MT) was found to improve motor function after stroke. However, there is high variability between patients regarding motor recovery. The following pilot study was designed to identify potential factors determining this variability between patients with severe upper limb paresis, receiving MT. Eleven sub-acute stroke patients with severe upper limb paresis participated, receiving in-patient rehabilitation. After a set of pre-assessments (including measurement of brain activity at the primary motor cortex and precuneus during the mirror illusion, using near-infrared spectroscopy as described previously), four weeks of MT were applied, followed by a set of post-assessments. Discriminant group analysis for MT responders and non-responders was performed. Six out of eleven patients were defined as responders and five as non-responders on the basis of their functional motor improvement. The initial motor function and the activity shift in both precunei (mirror index) were found to discriminate significantly between responders and non-responders. In line with earlier results, initial motor function was confirmed as crucial determinant of motor recovery. Additionally, activity response to the mirror illusion in both precunei was found to be a candidate for determination of the efficacy of MT.

Prospective versus predictive control in timing of hitting a falling ball.

PubMed

Katsumata, Hiromu; Russell, Daniel M

2012-02-01

Debate exists as to whether humans use prospective or predictive control to intercept an object falling under gravity (Baurès et al. in Vis Res 47:2982-2991, 2007; Zago et al. in Vis Res 48:1532-1538, 2008). Prospective control involves using continuous information to regulate action. τ, the ratio of the size of the gap to the rate of gap closure, has been proposed as the information used in guiding interceptive actions prospectively (Lee in Ecol Psychol 10:221-250, 1998). This form of control is expected to generate movement modulation, where variability decreases over the course of an action based upon more accurate timing information. In contrast, predictive control assumes that a pre-programmed movement is triggered at an appropriate criterion timing variable. For a falling object it is commonly argued that an internal model of gravitational acceleration is used to predict the motion of the object and determine movement initiation. This form of control predicts fixed duration movements initiated at consistent time-to-contact (TTC), either across conditions (constant criterion operational timing) or within conditions (variable criterion operational timing). The current study sought to test predictive and prospective control hypotheses by disrupting continuous visual information of a falling ball and examining consistency in movement initiation and duration, and evidence for movement modulation. Participants (n = 12) batted a ball dropped from three different heights (1, 1.3 and 1.5 m), under both full-vision and partial occlusion conditions. In the occlusion condition, only the initial ball drop and the final 200 ms of ball flight to the interception point could be observed. The initiation of the swing did not occur at a consistent TTC, τ, or any other timing variable across drop heights, in contrast with previous research. However, movement onset was not impacted by occluding the ball flight for 280-380 ms. This finding indicates that humans did not need to be continuously coupled to vision of the ball to initiate the swing accurately, but instead could use predictive control based on acceleration timing information (TTC2). However, other results provide evidence for movement modulation, a characteristic of prospective control. Strong correlations between movement initiation and duration and reduced timing variability from swing onset to arrival at the interception point, both support compensatory variability. An analysis of modulation within the swing revealed that early in the swing, the movement acceleration was strongly correlated to the required mean velocity at swing onset and that later in the swing, the movement acceleration was again strongly correlated with the current required mean velocity. Rather than a consistent movement initiated at the same time, these findings show that the swing was variable but modulated for meeting the demands of each trial. A prospective model of coupling τ (bat-ball) with τ (ball-target) was found to provide a very strong linear fit for an average of 69% of the movement duration. These findings provide evidence for predictive control based on TTC2 information in initiating the swing and prospective control based on τ in guiding the bat to intercept the ball.

Effects of model error on control of large flexible space antenna with comparisons of decoupled and linear quadratic regulator control procedures

NASA Technical Reports Server (NTRS)

Hamer, H. A.; Johnson, K. G.

1986-01-01

An analysis was performed to determine the effects of model error on the control of a large flexible space antenna. Control was achieved by employing two three-axis control-moment gyros (CMG's) located on the antenna column. State variables were estimated by including an observer in the control loop that used attitude and attitude-rate sensors on the column. Errors were assumed to exist in the individual model parameters: modal frequency, modal damping, mode slope (control-influence coefficients), and moment of inertia. Their effects on control-system performance were analyzed either for (1) nulling initial disturbances in the rigid-body modes, or (2) nulling initial disturbances in the first three flexible modes. The study includes the effects on stability, time to null, and control requirements (defined as maximum torque and total momentum), as well as on the accuracy of obtaining initial estimates of the disturbances. The effects on the transients of the undisturbed modes are also included. The results, which are compared for decoupled and linear quadratic regulator (LQR) control procedures, are shown in tabular form, parametric plots, and as sample time histories of modal-amplitude and control responses. Results of the analysis showed that the effects of model errors on the control-system performance were generally comparable for both control procedures. The effect of mode-slope error was the most serious of all model errors.

Between-Subject Variability in the Breaking Continuous Flash Suppression Paradigm: Potential Causes, Consequences, and Solutions

PubMed Central

Gayet, Surya; Stein, Timo

2017-01-01

A recent focus in the field of consciousness research involves investigating the propensity of initially non-conscious visual information to gain access to consciousness. A critical tool for measuring conscious access is the so-called breaking continuous flash suppression paradigm (b-CFS). In this paradigm, a high contrast dynamic pattern is presented to one eye, thereby temporarily suppressing a target stimulus that is presented to the other eye. The time it takes for observers to report (e.g., the location of) the initially suppressed stimulus provides a measure of conscious access. Typical observations in b-CFS studies include the finding that upright faces are released from suppression faster than inverted faces, and the finding that stimuli that match the current content of visual working memory are released from suppression faster than mismatching stimuli. Interestingly, the extent to which observers exhibit these effects varies extensively (in the range of hundreds of milliseconds). By re-analyzing existing datasets and a new dataset we establish that the difference in RTs between conditions in b-CFS tasks (i.e., the effect of interest) is highly correlated with participants' overall suppression durations, and with their trial-to-trial variability in RTs. We advocate the usage of a simple latency- normalization method, which (1) removes the between-subject variability in suppression duration from the effect of interest, while (2) providing distributions of RT differences that are better suited for parametric testing. We next compare this latency-normalization method to two other transformations that are widely applied on within-subject RT data (z-transformations and log-transformations). Finally, we tentatively discuss how trial-to-trial variability and overall suppression duration might relate to prolonged phases of shallow suppression that are more prone to modulations of conscious access. PMID:28396645

Identification of the significant factors in food safety using global sensitivity analysis and the accept-and-reject algorithm: application to the cold chain of ham.

PubMed

Duret, Steven; Guillier, Laurent; Hoang, Hong-Minh; Flick, Denis; Laguerre, Onrawee

2014-06-16

Deterministic models describing heat transfer and microbial growth in the cold chain are widely studied. However, it is difficult to apply them in practice because of several variable parameters in the logistic supply chain (e.g., ambient temperature varying due to season and product residence time in refrigeration equipment), the product's characteristics (e.g., pH and water activity) and the microbial characteristics (e.g., initial microbial load and lag time). This variability can lead to different bacterial growth rates in food products and has to be considered to properly predict the consumer's exposure and identify the key parameters of the cold chain. This study proposes a new approach that combines deterministic (heat transfer) and stochastic (Monte Carlo) modeling to account for the variability in the logistic supply chain and the product's characteristics. The model generates a realistic time-temperature product history , contrary to existing modeling whose describe time-temperature profile Contrary to existing approaches that use directly a time-temperature profile, the proposed model predicts product temperature evolution from the thermostat setting and the ambient temperature. The developed methodology was applied to the cold chain of cooked ham including, the display cabinet, transport by the consumer and the domestic refrigerator, to predict the evolution of state variables, such as the temperature and the growth of Listeria monocytogenes. The impacts of the input factors were calculated and ranked. It was found that the product's time-temperature history and the initial contamination level are the main causes of consumers' exposure. Then, a refined analysis was applied, revealing the importance of consumer behaviors on Listeria monocytogenes exposure. Copyright © 2014. Published by Elsevier B.V.

Segment coupling and coordination variability analyses of the roundhouse kick in taekwondo relative to the initial stance position.

PubMed

Estevan, Isaac; Freedman Silvernail, Julia; Jandacka, Daniel; Falco, Coral

2016-09-01

The initial stance position (ISP) has been observed as a factor affecting the execution technique during taekwondo kicks. In the present study, authors aimed to analyse a roundhouse kick to the chest by measuring movement coordination and the variability of coordination and comparing this across the different ISP (0°, 45° and 90°). Eight experienced taekwondo athletes performed consecutive kicking trials in random order from every of the three relative positions. The execution was divided into three phases (stance, first swing and second swing phase). A motion capture system was used to measure athletes' angular displacement of pelvis and thigh. A modified vector coding technique was used to quantify the coordination of the segments which contributed to the overall movement. The variability of this coordination (CV) for each ISP was also calculated. Comparative analysis showed that during the stance phase in the transverse plane, athletes coordinated movement of the trunk and thigh with a higher frequency of in-phase and lower frequency of exclusive thigh rotation in the 0° stance than the 90° stance position (P < 0.05). CV was also influenced by the different ISP. During the first swing and the majority of the second swing phase, predominant in-phase coordination of the pelvis and thigh was observed. Including exercises that require in-phase movement could not only help athletes to acquire coordination stability but also efficiency. The existence of a constraint such as ISP implies an increase of the variability when the athletes have to kick from ISP they are not used to adopt (i.e., 0° and 90° ISP) as an evidence of adaptability in the athletes' execution technique.

Some lessons from NACA/NASA aerodynamic studies following World War II

NASA Technical Reports Server (NTRS)

Spearman, M. L.

1983-01-01

An historical account is presented of the new departures in aerodynamic research conducted by NACA, and subsequently NASA, as a result of novel aircraft technologies and operational regimes encountered in the course of the Second World War. The invention and initial development of the turbojet engine furnished the basis for a new speed/altitude regime in which numerous aerodynamic design problems arose. These included compressibility effects near the speed of sound, with attendant lift/drag efficiency reductions and longitudinal stability enhancements that were accompanied by a directional stability reduction. Major research initiatives were mounted in the investigation of swept, delta, trapezoidal and variable sweep wing configurations, sometimes conducted through flight testing of the 'X-series' aircraft. Attention is also given to the development of the first generation of supersonic fighter aircraft.

Multihospital System Membership and Patient Treatments, Expenditures, and Outcomes

PubMed Central

Madison, Kristin

2004-01-01

Objective To determine the relationship between hospital membership in systems and the treatments, expenditures, and outcomes of patients. Data Sources The Medicare Provider Analysis and Review dataset, for data on Medicare patients admitted to general medical-surgical hospitals between 1985 and 1998 with a diagnosis of acute myocardial infarction (AMI); the American Hospital Association Annual Survey, for data on hospitals. Study Design A multivariate regression analysis. An observation is a fee-for-service Medicare AMI patient admitted to a study hospital. Dependent variables include patient transfers, catheterizations, angioplasties or bypass surgeries, 90-day mortality, and Medicare expenditures. Independent variables include system participation, other admission hospital and patient traits, and hospital and year fixed effects. The five-part system definition incorporates the size and location of the index admission hospital and the size and distance of its partners. Principal Findings While the effects of multihospital system membership on patients are in general limited, patients initially admitted to small rural system hospitals that have big partners within 100 miles experience lower mortality rates than patients initially admitted to independent hospitals. Regression results show that to the extent system hospital patients experience differences in treatments and outcomes relative to patients of independent hospitals, these differences remain even after controlling for the admission hospital's capacity to provide cardiac services. Conclusions Multihospital system participation may affect AMI patient treatment and outcomes through factors other than cardiac service offerings. Additional investigation into the nature of these factors is warranted. PMID:15230926

Early Activation of Ventral Hippocampus and Subiculum during Spontaneous Seizures in a Rat Model of Temporal Lobe Epilepsy

PubMed Central

Toyoda, Izumi; Bower, Mark R.; Leyva, Fernando

2013-01-01

Temporal lobe epilepsy is the most common form of epilepsy in adults. The pilocarpine-treated rat model is used frequently to investigate temporal lobe epilepsy. The validity of the pilocarpine model has been challenged based largely on concerns that seizures might initiate in different brain regions in rats than in patients. The present study used 32 recording electrodes per rat to evaluate spontaneous seizures in various brain regions including the septum, dorsomedial thalamus, amygdala, olfactory cortex, dorsal and ventral hippocampus, substantia nigra, entorhinal cortex, and ventral subiculum. Compared with published results from patients, seizures in rats tended to be shorter, spread faster and more extensively, generate behavioral manifestations more quickly, and produce generalized convulsions more frequently. Similarities to patients included electrographic waveform patterns at seizure onset, variability in sites of earliest seizure activity within individuals, and variability in patterns of seizure spread. Like patients, the earliest seizure activity in rats was recorded most frequently within the hippocampal formation. The ventral hippocampus and ventral subiculum displayed the earliest seizure activity. Amygdala, olfactory cortex, and septum occasionally displayed early seizure latencies, but not above chance levels. Substantia nigra and dorsomedial thalamus demonstrated consistently late seizure onsets, suggesting their unlikely involvement in seizure initiation. The results of the present study reveal similarities in onset sites of spontaneous seizures in patients with temporal lobe epilepsy and pilocarpine-treated rats that support the model's validity. PMID:23825415

Green initiative impact on stock prices: A quantitative study of the clean energy industry

NASA Astrophysics Data System (ADS)

Jurisich, John M.

The purpose of this quantitative ex post facto research study was to explore the relationship between green initiative expense disclosures and stock prices of 46 NASDAQ listed Clean Edge Green Energy global companies from 2007 to 2010. The independent variables were sales and marketing, environmental, customer and supplier, community, and corporate governance practices that were correlated with the dependent variable in the study of stock prices. Expense disclosures were examined in an effort to measure the impact of green initiative programs and to expose the interrelationships between green initiative expense disclosures and fluctuations of stock prices. The data for the research was secondary data from existing annual reports. A statistically significant relationship was revealed between environmental practices and changes in stock prices. The study results also provided substantial evidence for leadership and managerial decision making to reduce or increase green initiative practices to maximize shareholder wealth of their respective organizations.

Patient initiated clinics for patients with chronic or recurrent conditions managed in secondary care: a systematic review of patient reported outcomes and patient and clinician satisfaction

PubMed Central

2013-01-01

Background The cost to the NHS of missed or inappropriate hospital appointments is considerable. Alternative methods of appointment scheduling might be more flexible to patients’ needs without jeopardising health and service quality. The objective was to systematically review evidence of patient initiated clinics in secondary care on patient reported outcomes among patients with chronic/recurrent conditions. Methods Seven databases were searched from inception to June 2013. Hand searching of included studies references was also conducted. Studies comparing the effects of patient initiated clinics with traditional consultant led clinics in secondary care for patients with long term chronic or recurrent diseases on health related quality of life and/or patient satisfaction were included. Data was extracted by one reviewer and checked by a second. Results were synthesised narratively. Results Seven studies were included in the review, these covered a total of 1,655 participants across three conditions: breast cancer, inflammatory bowel disease and rheumatoid arthritis. Quality of reporting was variable. Results showed no significant differences between the intervention and control groups for psychological and health related quality of life outcomes indicating no evidence of harm. Some patients reported significantly more satisfaction using patient-initiated clinics than usual care (p < 0.001). Conclusions The results show potential for patient initiated clinics to result in greater patient and clinician satisfaction. The patient-consultant relationship appeared to play an important part in patient satisfaction and should be considered an important area of future research as should the presence or absence of a guidebook to aid self-management. Patient initiated clinics fit the models of care suggested by policy makers and so further research into long term outcomes for patients and service use in this area of practice is both relevant and timely. PMID:24289832

Within-site variability in surveys of wildlife populations

USGS Publications Warehouse

Link, William A.; Barker, Richard J.; Sauer, John R.; Droege, Sam

1994-01-01

Most large-scale surveys of animal populations are based on counts of individuals observed during a sampling period, which are used as indexes to the population. The variability in these indexes not only reflects variability in population sizes among sites but also variability due to the inexactness of the counts. Repeated counts at survey sites can be used to document this additional source of variability and, in some applications, to mitigate its effects. We present models for evaluating the proportion of total variability in counts that is attributable to this within-site variability and apply them in the analysis of data from repeated counts on routes from the North American Breeding Bird Survey. We analyzed data on 98 species, obtaining estimates of these percentages, which ranged from 3.5 to 100% with a mean of 36.25%. For at least 14 of the species, more than half of the variation in counts was attributable to within-site sources. Counts for species with lower average counts had a higher percentage of within-site variability. We discuss the relative cost efficiency of replicating sites or initiating new sites for several objectives, concluding that it is frequently better to initiate new sites than to attempt to replicate existing sites.

Estimate of Shock-Hugoniot Adiabat of Liquids from Hydrodynamics

NASA Astrophysics Data System (ADS)

Bouton, E.; Vidal, P.

2007-12-01

Shock states are generally obtained from shock velocity (D) and material velocity (u) measurements. In this paper, we propose a hydrodynamical method for estimating the (D-u) relation of Nitromethane from easily measured properties of the initial state. The method is based upon the differentiation of the Rankine-Hugoniot jump relations with the initial temperature considered as a variable and under the constraint of a unique nondimensional shock-Hugoniot. We then obtain an ordinary differential equation for the shock velocity D in the variable u. Upon integration, this method predicts the shock Hugoniot of liquid Nitromethane with a 5% accuracy for initial temperatures ranging from 250 K to 360 K.

Genetic Algorithm for Initial Orbit Determination with Too Short Arc

NASA Astrophysics Data System (ADS)

Li, Xin-ran; Wang, Xin

2017-01-01

A huge quantity of too-short-arc (TSA) observational data have been obtained in sky surveys of space objects. However, reasonable results for the TSAs can hardly be obtained with the classical methods of initial orbit determination (IOD). In this paper, the IOD is reduced to a two-stage hierarchical optimization problem containing three variables for each stage. Using the genetic algorithm, a new method of the IOD for TSAs is established, through the selections of the optimized variables and the corresponding genetic operators for specific problems. Numerical experiments based on the real measurements show that the method can provide valid initial values for the follow-up work.

Genetic Algorithm for Initial Orbit Determination with Too Short Arc

NASA Astrophysics Data System (ADS)

Li, X. R.; Wang, X.

2016-01-01

The sky surveys of space objects have obtained a huge quantity of too-short-arc (TSA) observation data. However, the classical method of initial orbit determination (IOD) can hardly get reasonable results for the TSAs. The IOD is reduced to a two-stage hierarchical optimization problem containing three variables for each stage. Using the genetic algorithm, a new method of the IOD for TSAs is established, through the selection of optimizing variables as well as the corresponding genetic operator for specific problems. Numerical experiments based on the real measurements show that the method can provide valid initial values for the follow-up work.

Early Adolescent Sexual Initiation and Physical/Psychological Symptoms: A Comparative Analysis of Five Nations

PubMed Central

Farhat, Tilda; Halpern, Carolyn Tucker; Godeau, Emmanuelle; Gabhainn, Saoirse Nic

2010-01-01

Although most people in developed countries experience sexual initiation during adolescence, little is known about inter-country variability in the psychosocial correlates of early initiation. Population-based samples of 15-year-olds (n = 6,111, 52% female) who participated in the Health Behaviors in School-Aged Children Study (Finland, Scotland, France and Poland, 1997/1998) or the National Longitudinal Study of Adolescent Health (United States, 1996) self-reported sexual intercourse experience and physical (headaches, trouble sleeping) or psychological (unhappiness, loneliness, sadness, moodiness) symptoms. Analyses were conducted stratified by gender. Sexual initiation prevalence and symptoms scores varied significantly across nations. In adjusted models, sexual initiation was not related to symptoms among boys in any nation, but significantly positively related to symptoms among girls in Poland and the US. Results support variability by gender and nation in the relationship between adolescents’ sexual initiation and physical/psychological symptoms. Empirically investigating specific features of national contexts that generate these differences should be explored further. PMID:20333456

Early adolescent sexual initiation and physical/psychological symptoms: a comparative analysis of five nations.

PubMed

Madkour, Aubrey Spriggs; Farhat, Tilda; Halpern, Carolyn Tucker; Godeau, Emmanuelle; Nic Gabhainn, Saoirse

2010-10-01

Although most people in developed countries experience sexual initiation during adolescence, little is known about inter-country variability in the psychosocial correlates of early initiation. Population-based samples of 15-year-olds (n = 6,111, 52% female) who participated in the Health Behaviors in School-Aged Children Study (Finland, Scotland, France and Poland, 1997/1998) or the National Longitudinal Study of Adolescent Health (United States, 1996) self-reported sexual intercourse experience and physical (headaches, trouble sleeping) or psychological (unhappiness, loneliness, sadness, moodiness) symptoms. Analyses were conducted stratified by gender. Sexual initiation prevalence and symptoms scores varied significantly across nations. In adjusted models, sexual initiation was not related to symptoms among boys in any nation, but significantly positively related to symptoms among girls in Poland and the US. Results support variability by gender and nation in the relationship between adolescents' sexual initiation and physical/psychological symptoms. Empirically investigating specific features of national contexts that generate these differences should be explored further.

Treatment intensification using long-acting insulin -predictors of future basal insulin supported oral therapy in the DIVE registry.

PubMed

Danne, Thomas; Bluhmki, Tobias; Seufert, Jochen; Kaltheuner, Matthias; Rathmann, Wolfgang; Beyersmann, Jan; Bramlage, Peter

2015-10-07

In patients with type-2 diabetes receiving oral antidiabetic drugs (OADs), the addition of insulin is frequently required to achieve sufficient control over blood glucose levels. It is, however, difficult to predict if, when and in which patients insulin therapy will be needed. We aimed to identify patient related variables associated with the addition of basal insulin to oral therapy resulting in a basal supported oral therapy (BOT). DIVE (DIabetes Versorgungs-Evaluation) is a prospective, observational, multi-centre diabetes registry established in Germany in 2011. For the present explorative analysis, 31,008 patients with type-2 diabetes prescribed at least one OAD were included. Patients who had previously received insulin and those over 90 years old were excluded. The event of interest was defined as the initiation of BOT during the observational period. Cause-specific Cox proportional hazards models based on a competing risk framework were applied for risk quantification. Multivariable adjusted hazard ratios demonstrated that longer diabetes duration, higher BMI, poorer glycaemic control, documentation of any micro- or macrovascular comorbidity, the presence of concomitant non-antidiabetic pharmacotherapies, and greater numbers of prescribed OADs increased the likelihood of BOT initiation. On the other hand BOT initiation was less likely in patients with older age and female gender. Analysing the likelihood of OAD termination without initiation of BOT provided supportive evidence for the variables predictive of BOT initiation. Analysis of the DIVE registry has resulted in the identification of a number of factors that may be predictive for the initiation of BOT for type-2 diabetes patients initially prescribed one or more OADs. Poor glycaemic control, the presence of vascular comorbidities and concomitant medications, and a greater number of OADs were all detected to increase the risk of a switch to BOT. Female gender and younger age showed protective properties. The close monitoring of patients displaying these characteristics may help to identify individuals who might benefit from early addition of insulin therapy to their oral treatment regimen.

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

Best, William M. J.; Liu, Michael C.; Magnier, Eugene A.

We present initial results from a wide-field (30,000 deg{sup 2}) search for L/T transition brown dwarfs within 25 pc using the Pan-STARRS1 and Wide-field Infrared Survey Explorer (WISE) surveys. Previous large-area searches have been incomplete for L/T transition dwarfs, because these objects are faint in optical bands and have near-infrared (near-IR) colors that are difficult to distinguish from background stars. To overcome these obstacles, we have cross-matched the Pan-STARRS1 (optical) and WISE (mid-IR) catalogs to produce a unique multi-wavelength database for finding ultracool dwarfs. As part of our initial discoveries, we have identified seven brown dwarfs in the L/T transitionmore » within 9-15 pc of the Sun. The L9.5 dwarf PSO J140.2308+45.6487 and the T1.5 dwarf PSO J307.6784+07.8263 (both independently discovered by Mace et al.) show possible spectroscopic variability at the Y and J bands. Two more objects in our sample show evidence of photometric J-band variability, and two others are candidate unresolved binaries based on their spectra. We expect our full search to yield a well-defined, volume-limited sample of L/T transition dwarfs that will include many new targets for study of this complex regime. PSO J307.6784+07.8263 in particular may be an excellent candidate for in-depth study of variability, given its brightness (J = 14.2 mag) and proximity (11 pc)« less

Effect of private versus emergency medical systems transportation in motor vehicle accident victims: Trauma Center Experience in Saudi Arabia.

PubMed

Alshahrani, Mohammed S

2017-01-01

To assess the effect of the mode of transportation of trauma patients (emergency medical service [EMS] vs. non-EMS) on their final clinical outcome in terms of mortality and length of hospital stay. A retrospective study included all patients who were involved in motor vehicle crashes, and who were transferred immediately to an emergency department of a trauma care center from December 2008 to December 2012. Patients were classified into two groups: those brought through EMS and those brought by non-EMS (private transport). Information on demographic characteristics including age and gender was recorded and medical data such as blood pressure, pulse, oxygen saturation, temperature, initial Glasgow Coma Score (GCS), saturation, temperature, initial Glasgow Coma Score (GCS), injury severity score (ISS), and final outcome (discharged or expired) were obtained. Descriptive statistics, mean and standard deviation (SD) were computed for continuous variables and statistical significance was tested by t -test or Mann-Whitney U-test. Categorical variables were described by frequency distribution and percentages; Chi-square or Fisher's exact test as appropriate were employed to test for statistical significance. Logistics regression was performed with mortality as dependent variable and mode of transport and all demographic and prehospital variables as independent variables. A general linear model analysis was performed to test whether the mode of transport was significant to length of hospital stay in EMS and non-EMS clients. Out of 308 patients identified during the study period, 232 were transported through EMS and 76 through non-EMS. The two groups were similar with regard to mortality and length of stay. The crude mortality rate was 30.6% (95% confidence interval [CI]: 24.64-36.53) in the EMS group and 28.9% (95% CI: 18.44-38.76) in the non-EMS group ( p = 0.785). The average length of hospital stay was 9 days (interquartile range [IQR] = 8, 95% CI: 7.3-10.1) for the EMS group and 8 days (IQR = 9.5, 95% CI: 6.7-10.9) for the non-EMS group ( p = 0.803). Multivariate analysis showed that of the study variables, only the injury severity score (ISS) and Glasgow coma score (GCS) were significant to mortality ( p < 0.01), and GCS was more significant to the length of hospital stay ( p < 0.01). There was no significant difference between the EMS and non-EMS groups as they relate to mortality and length of stay in hospital. However, the mortality and length of hospital stay was statistically significant to ISS and GCS.

Factors Associated with Initiation of Ecstasy Use among US Adolescents: Findings from a National Survey

PubMed Central

Wu, Ping; Liu, Xinhua; Fan, Bin

2009-01-01

Aims To investigate adolescent pathways to ecstasy use by (1) examining how early onsets of smoking, drinking, and marijuana use are related to a child’s risk of initiation of ecstasy use and (2) assessing the influence of other individual and parental factors on ecstasy use initiation. Methods Data on 6,426 adolescents (12–17 years old at baseline) from the National Survey of Parents and Youth (NSPY), a longitudinal, nationally-representative household survey of youth and their parents, were used in the analyses. Information on youth substance use, including ecstasy use, as well as familial and parental characteristics, was available. Results Initiation of ecstasy use is predicted by an adolescent’s early initiation of smoking, drinking, or marijuana use. In particular, early initiation either of marijuana use, or of both smoking and drinking, increases a child’s risk for ecstasy use initiation. Among the familial and parental variables, parent drug use emerged as significantly predictive of child initiation of ecstasy use; living with both parents and close parental monitoring, on the other hand, are negatively associated with ecstasy use initiation, and may be protective against it. At the individual level, sensation seeking tendencies and positive attitudes toward substance use, as well as close associations with deviant peers, are predictive of adolescent initiation of ecstasy use. Conclusion Our findings on the risk and protective factors for initiation of ecstasy use, especially with regard to factors that are modifiable, will be useful for prevention programs targeting youth use not only of ecstasy, but also of other drugs. PMID:19781862

P09.62 Towards individualized survival prediction in glioblastoma patients using machine learning methods

PubMed Central

Vera, L.; Pérez-Beteta, J.; Molina, D.; Borrás, J. M.; Benavides, M.; Barcia, J. A.; Velásquez, C.; Albillo, D.; Lara, P.; Pérez-García, V. M.

2017-01-01

Abstract Introduction: Machine learning methods are integrated in clinical research studies due to their strong capability to discover parameters having a high information content and their predictive combined potential. Several studies have been developed using glioblastoma patient’s imaging data. Many of them have focused on including large numbers of variables, mostly two-dimensional textural features and/or genomic data, regardless of their meaning or potential clinical relevance. Materials and methods: 193 glioblastoma patients were included in the study. Preoperative 3D magnetic resonance images were collected and semi-automatically segmented using an in-house software. After segmentation, a database of 90 parameters including geometrical and textural image-based measures together with patients’ clinical data (including age, survival, type of treatment, etc.) was constructed. The criterion for including variables in the study was that they had either shown individual impact on survival in single or multivariate analyses or have a precise clinical or geometrical meaning. These variables were used to perform several machine learning experiments. In a first set of computational cross-validation experiments based on regression trees, those attributes showing the highest information measures were extracted. In the second phase, more sophisticated learning methods were employed in order to validate the potential of the previous variables predicting survival. Concretely support vector machines, neural networks and sparse grid methods were used. Results: Variables showing high information measure in the first phase provided the best prediction results in the second phase. Specifically, patient age, Stupp regimen and a geometrical measure related with the irregularity of contrast-enhancing areas were the variables showing the highest information measure in the first stage. For the second phase, the combinations of patient age and Stupp regimen together with one tumor geometrical measure and one tumor heterogeneity feature reached the best quality prediction. Conclusions: Advanced machine learning methods identified the parameters with the highest information measure and survival predictive potential. The uninformed machine learning methods identified a novel feature measure with direct impact on survival. Used in combination with other previously known variables multi-indexes can be defined that can help in tumor characterization and prognosis prediction. Recent advances on the definition of those multi-indexes will be reported in the conference. Funding: James S. Mc. Donnell Foundation (USA) 21st Century Science Initiative in Mathematical and Complex Systems Approaches for Brain Cancer [Collaborative award 220020450 and planning grant 220020420], MINECO/FEDER [MTM2015-71200-R], JCCM [PEII-2014-031-P].

Commercial launch systems: A risky investment?

NASA Astrophysics Data System (ADS)

Dupnick, Edwin; Skratt, John

1996-03-01

A myriad of evolutionary paths connect the current state of government-dominated space launch operations to true commercial access to space. Every potential path requires the investment of private capital sufficient to fund the commercial venture with a perceived risk/return ratio acceptable to the investors. What is the private sector willing to invest? Does government participation reduce financial risk? How viable is a commercial launch system without government participation and support? We examine the interplay between various forms of government participation in commercial launch system development, alternative launch system designs, life cycle cost estimates, and typical industry risk aversion levels. The boundaries of this n-dimensional envelope are examined with an ECON-developed business financial model which provides for the parametric assessment and interaction of SSTO design variables (including various operational scenarios with financial variables including debt/equity assumptions, and commercial enterprise burden rates on various functions. We overlay this structure with observations from previous ECON research which characterize financial risk aversion levels for selected industrial sectors in terms of acceptable initial lump-sum investments, cumulative investments, probability of failure, payback periods, and ROI. The financial model allows the construction of parametric tradeoffs based on ranges of variables which can be said to actually encompass the ``true'' cost of operations and determine what level of ``true'' costs can be tolerated by private capitalization.

Variable developmental delays and characteristic facial features-A novel 7p22.3p22.2 microdeletion syndrome?

PubMed

Yu, Andrea C; Zambrano, Regina M; Cristian, Ingrid; Price, Sue; Bernhard, Birgitta; Zucker, Marc; Venkateswaran, Sunita; McGowan-Jordan, Jean; Armour, Christine M

2017-06-01

Isolated 7p22.3p22.2 deletions are rarely described with only two reports in the literature. Most other reported cases either involve a much larger region of the 7p arm or have an additional copy number variation. Here, we report five patients with overlapping microdeletions at 7p22.3p22.2. The patients presented with variable developmental delays, exhibiting relative weaknesses in expressive language skills and relative strengths in gross, and fine motor skills. The most consistent facial features seen in these patients included a broad nasal root, a prominent forehead a prominent glabella and arched eyebrows. Additional variable features amongst the patients included microcephaly, metopic ridging or craniosynostosis, cleft palate, cardiac defects, and mild hypotonia. Although the patients' deletions varied in size, there was a 0.47 Mb region of overlap which contained 7 OMIM genes: EIP3B, CHST12, LFNG, BRAT1, TTYH3, AMZ1, and GNA12. We propose that monosomy of this region represents a novel microdeletion syndrome. We recommend that individuals with 7p22.3p22.2 deletions should receive a developmental assessment and a thorough cardiac exam, with consideration of an echocardiogram, as part of their initial evaluation. © 2017 Wiley Periodicals, Inc.

Evaluation of a safety training program in three food service companies.

PubMed

Sinclair, Raymond C; Smith, Randall; Colligan, Michael; Prince, Mary; Nguyen, Trang; Stayner, Leslie

2003-01-01

Outcome measures for safety training effectiveness research often do not include measures such as occupational injury experience. Effectiveness mediators also receive sparse attention. A new safety training curriculum was delivered to workers in a stratified random sample of food service facilities across three companies. A similar group of facilities received usual training. We collected post-test measures of demographic variables, safety knowledge, perceptions of transfer of training climate, and workers' compensation claim data for one year after the initial training activities. Knowledge test scores were apparently higher in the new-training units than in the usual-training units. Some demographic variables were inconsistently associated with these differences. Evidence for reduction of the injury rate associated with the new training was observed from two companies but only approached significance for one company. A second company revealed a similar but non-significant trend. Knowledge scores were not significantly associated with lower injury rates. We found evidence that safety training increases knowledge and reduces injuries. We found almost no evidence of effects of training effectiveness mediators, including no relationship between safety knowledge and injury experience. Methodological issues related to conducting a large study may have influenced these results. Although safety training leads to greater knowledge and, in some cases, reduced occupational injuries, the influence of mediating variables remains to be fully explained.

Application of Taguchi Design and Response Surface Methodology for Improving Conversion of Isoeugenol into Vanillin by Resting Cells of Psychrobacter sp. CSW4.

PubMed

Ashengroph, Morahem; Nahvi, Iraj; Amini, Jahanshir

2013-01-01

For all industrial processes, modelling, optimisation and control are the keys to enhance productivity and ensure product quality. In the current study, the optimization of process parameters for improving the conversion of isoeugenol to vanillin by Psychrobacter sp. CSW4 was investigated by means of Taguchi approach and Box-Behnken statistical design under resting cell conditions. Taguchi design was employed for screening the significant variables in the bioconversion medium. Sequentially, Box-Behnken design experiments under Response Surface Methodology (RSM) was used for further optimization. Four factors (isoeugenol, NaCl, biomass and tween 80 initial concentrations), which have significant effects on vanillin yield, were selected from ten variables by Taguchi experimental design. With the regression coefficient analysis in the Box-Behnken design, a relationship between vanillin production and four significant variables was obtained, and the optimum levels of the four variables were as follows: initial isoeugenol concentration 6.5 g/L, initial tween 80 concentration 0.89 g/L, initial NaCl concentration 113.2 g/L and initial biomass concentration 6.27 g/L. Under these optimized conditions, the maximum predicted concentration of vanillin was 2.25 g/L. These optimized values of the factors were validated in a triplicate shaking flask study and an average of 2.19 g/L for vanillin, which corresponded to a molar yield 36.3%, after a 24 h bioconversion was obtained. The present work is the first one reporting the application of Taguchi design and Response surface methodology for optimizing bioconversion of isoeugenol into vanillin under resting cell conditions.

Demographic and socioenvironmental predictors of premorbid marijuana use among patients with first-episode psychosis.

PubMed

Pauselli, Luca; Birnbaum, Michael L; Vázquez Jaime, Beatriz Paulina; Paolini, Enrico; Kelley, Mary E; Broussard, Beth; Compton, Michael T

2018-01-31

We identified, in subjects with first-episode psychosis, demographic and socioenvironmental predictors of three variables pertaining to premorbid marijuana use: age at initiation of marijuana use, trajectories of marijuana use in the five years prior to onset of psychosis, and the cumulative "dose" of marijuana intake in that same premorbid period. We enrolled 247 first-episode psychosis patients and collected data on lifetime marijuana/alcohol/tobacco use, age at onset of psychosis, diverse socioenvironmental variables, premorbid adjustment, past traumatic experiences, perceived neighborhood-level social disorder, and cannabis use experiences. Bivariate tests were used to examine associations between the three premorbid marijuana use variables and hypothesized predictors. Regression models determined which variables remained independently significantly associated. Age at initiation of cigarette smoking was linked to earlier initiation, faster escalation, and higher cumulative dose of premorbid marijuana use. During childhood, poorer academic performance was predictive of an earlier age at initiation of marijuana use, while poorer sociability was related to more rapid escalation to daily use and a higher cumulative dose. As expected, experiencing euphoric effects was positively correlated with trajectories and cumulative dose, but having negative experiences was unrelated. Traumatic childhood/adolescent experiences were correlated with rapid escalation and amount of marijuana used, but not with age at initiation of marijuana use. These data expand the very limited literature on predictors of premorbid marijuana use in first-episode psychosis. Given its association with earlier age at onset of psychosis, and poorer outcomes among first-episode patients, prevention and treatment efforts should be further developed. Copyright © 2018 Elsevier B.V. All rights reserved.

Biomechanical Differences of Foot-Strike Patterns During Running: A Systematic Review With Meta-analysis.

PubMed

Almeida, Matheus O; Davis, Irene S; Lopes, Alexandre D

2015-10-01

Systematic review with meta-analysis. To determine the biomechanical differences between foot-strike patterns used when running. Strike patterns during running have received attention in the recent literature due to their potential mechanical differences and associated injury risks. Electronic databases (MEDLINE, Embase, LILACS, SciELO, and SPORTDiscus) were searched through July 2014. Studies (cross-sectional, case-control, prospective, and retrospective) comparing the biomechanical characteristics of foot-strike patterns during running in distance runners at least 18 years of age were included in this review. Two independent reviewers evaluated the risk of bias. A meta-analysis with a random-effects model was used to combine the data from the included studies. Sixteen studies were included in the final analysis. In the meta-analyses of kinematic variables, significant differences between forefoot and rearfoot strikers were found for foot and knee angle at initial contact and knee flexion range of motion. A forefoot-strike pattern resulted in a plantar-flexed ankle position and a more flexed knee position, compared to a dorsiflexed ankle position and a more extended knee position for the rearfoot strikers, at initial contact with the ground. In the comparison of rearfoot and midfoot strikers, midfoot strikers demonstrated greater ankle dorsiflexion range of motion and decreased knee flexion range of motion compared to rearfoot strikers. For kinetic variables, the meta-analysis revealed that rearfoot strikers had higher vertical loading rates compared to forefoot strikers. There are differences in kinematic and kinetic characteristics between foot-strike patterns when running. Clinicians should be aware of these characteristics to help in the management of running injuries and advice on training.

Predictors of a variceal source among patients presenting with upper gastrointestinal bleeding.

PubMed

Alharbi, Ahmad; Almadi, Majid; Barkun, Alan; Martel, Myriam

2012-04-01

Patients with upper gastrointestinal bleeding (UGIB) require an early, tailored approach best guided by knowledge of the bleeding lesion, especially a variceal versus a nonvariceal source. To identify, by investigating a large national registry, variables that would be predictive of a variceal origin of UGIB using clinical parameters before endoscopic evaluation. A retrospective study was conducted in 21 Canadian hospitals during the period from January 2004 until the end of May 2005. Consecutive charts for hospitalized patients with a primary or secondary discharge diagnosis of UGIB were reviewed. Data regarding demographics, including historical, physical examination, initial laboratory investigations, endoscopic and pharmacological therapies administered, as well as clinical outcomes, were collected. Multivariable logistic regression modelling was performed to identify clinical predictors of a variceal source of bleeding. The patient population included 2020 patients (mean [± SD] age 66.3±16.4 years; 38.4% female). Overall, 215 (10.6%) were found to be bleeding from upper gastrointestinal varices. Among 26 patient characteristics, variables predicting a variceal source of bleeding included history of liver disease (OR 6.36 [95% CI 3.59 to 11.3]), excessive alcohol use (OR 2.28 [95% CI 1.37 to 3.77]), hematemesis (OR 2.65 [95% CI 1.61 to 4.36]), hematochezia (OR 3.02 [95% CI 1.46 to 6.22]) and stigmata of chronic liver disease (OR 2.49 [95% CI 1.46 to 4.25]). Patients treated with antithrombotic therapy were more likely to experience other causes of hemorrhage (OR 0.44 [95% CI 0.35 to 0.78]). Presenting historical and physical examination data, and initial laboratory tests carry significant predictive ability in discriminating variceal versus nonvariceal sources of bleeding.

The impact of football training on motor development in male children.

PubMed

Erceg, Marko; Zagorac, Nebojsa; Katić, Ratko

2008-03-01

The aim of the study was to determine the effect of football school program and physical education curriculum on changes in the motor abilities of 7- and 8-year-old boys. The study included a sample of 180 boys divided into group 1 (7-year-old boys), subdivided to experimental (n = 40) and control (n = 50) groups, and group 2 (8-year-old boys), subdivided to experimental (n = 40) and control (n = 50) groups. Experimental groups included children attending three training units of football training over a 9-month period, in addition to the conventional physical education curriculum. Control groups included children attending only conventional physical education curriculum. All study subjects underwent testing with a battery of 12 motor tests at the beginning and at the end of the study. Results obtained by discriminative canonic analysis showed no statistically significant between-group difference in motor abilities at the beginning of the study. However, significant differences in favor of experimental groups were recorded at the end of the study. Favorable changes in all motor variables were observed in both experimental and control groups of children from the initial through the final state. These changes were more pronounced in experimental groups. Analysis of variance for difference variables (final to initial measurement) indicated programmed education in the form of football training in addition to regular physical education curriculum to predominantly influence the development of aerobic endurance, agility, speed and flexibility in 7-year-old boys, and of explosive strength, aerobic endurance, flexibility and speed in 8-year-old boys. In the latter, football training led to the formation of a motor complex integrating explosiveness, speed, coordination, endurance and flexibility as a general motor factor determining future quality development in football.

Physician communication in the operating room: expanding application of face-negotiation theory to the health communication context.

PubMed

Kirschbaum, Kristin

2012-01-01

Communication variables that are associated with face-negotiation theory were examined in a sample of operating-room physicians. A survey was administered to anesthesiologists and surgeons at a teaching hospital in the southwestern United States to measure three variables commonly associated with face-negotiation theory: conflict-management style, face concern, and self-construal. The survey instrument that was administered to physicians includes items that measured these three variables in previous face-negotiation research with slight modification of item wording for relevance in the medical setting. The physician data were analyzed using confirmatory factor analysis, Pearson's correlations, and t-tests. Results of this initial investigation showed that variables associated with face-negotiation theory were evident in the sample physician population. In addition, the correlations were similar among variables in the medical sample as those found in previous face-negotiation research. Finally, t-tests suggest variance between anesthesiologists and surgeons on specific communication variables. These findings suggest three implications that warrant further investigation with expanded sample size: (1) An intercultural communication theory and instrument can be utilized for health communication research; (2) as applied in a medical context, face-negotiation theory can be expanded beyond traditional intercultural communication boundaries; and (3) theoretically based communication structures applied in a medical context could help explain physician miscommunication in the operating room to assist future design of communication training programs for operating-room physicians.

Explanatory model of emotional-cognitive variables in school mathematics performance: a longitudinal study in primary school

PubMed Central

Cerda, Gamal; Pérez, Carlos; Navarro, José I.; Aguilar, Manuel; Casas, José A.; Aragón, Estíbaliz

2015-01-01

This study tested a structural model of cognitive-emotional explanatory variables to explain performance in mathematics. The predictor variables assessed were related to students’ level of development of early mathematical competencies (EMCs), specifically, relational and numerical competencies, predisposition toward mathematics, and the level of logical intelligence in a population of primary school Chilean students (n = 634). This longitudinal study also included the academic performance of the students during a period of 4 years as a variable. The sampled students were initially assessed by means of an Early Numeracy Test, and, subsequently, they were administered a Likert-type scale to measure their predisposition toward mathematics (EPMAT) and a basic test of logical intelligence. The results of these tests were used to analyse the interaction of all the aforementioned variables by means of a structural equations model. This combined interaction model was able to predict 64.3% of the variability of observed performance. Preschool students’ performance in EMCs was a strong predictor for achievement in mathematics for students between 8 and 11 years of age. Therefore, this paper highlights the importance of EMCs and the modulating role of predisposition toward mathematics. Also, this paper discusses the educational role of these findings, as well as possible ways to improve negative predispositions toward mathematical tasks in the school domain. PMID:26441739

Interannual variability in global mean sea level estimated from the CESM Large and Last Millennium Ensembles

DOE PAGES

Fasullo, John T.; Nerem, Robert S.

2016-10-31

To better understand global mean sea level (GMSL) as an indicator of climate variability and change, contributions to its interannual variation are quantified in the Community Earth System Model (CESM) Large Ensemble and Last Millennium Ensemble. Consistent with expectations, the El Niño/Southern Oscillation (ENSO) is found to exert a strong influence due to variability in rainfall over land (PL) and terrestrial water storage (TWS). Other important contributors include changes in ocean heat content (OHC) and precipitable water (PW). The temporal evolution of individual contributing terms is documented. The magnitude of peak GMSL anomalies associated with ENSO generally are of themore » order of 0.5 mm·K -1 with significant inter-event variability, with a standard deviation (σ) that is about half as large The results underscore the exceptional rarity of the 2010/2011 La Niña-related GMSL drop and estimate the frequency of such an event to be about only once in every 75 years. In addition to ENSO, major volcanic eruptions are found to be a key driver of interannual variability. Associated GMSL variability contrasts with that of ENSO as TWS and PW anomalies initially offset the drop due to OHC reductions but short-lived relative to them. Furthermore, responses up to 25 mm are estimated for the largest eruptions of the Last Millennium.« less

Interannual variability in global mean sea level estimated from the CESM Large and Last Millennium Ensembles

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

Fasullo, John T.; Nerem, Robert S.

To better understand global mean sea level (GMSL) as an indicator of climate variability and change, contributions to its interannual variation are quantified in the Community Earth System Model (CESM) Large Ensemble and Last Millennium Ensemble. Consistent with expectations, the El Niño/Southern Oscillation (ENSO) is found to exert a strong influence due to variability in rainfall over land (PL) and terrestrial water storage (TWS). Other important contributors include changes in ocean heat content (OHC) and precipitable water (PW). The temporal evolution of individual contributing terms is documented. The magnitude of peak GMSL anomalies associated with ENSO generally are of themore » order of 0.5 mm·K -1 with significant inter-event variability, with a standard deviation (σ) that is about half as large The results underscore the exceptional rarity of the 2010/2011 La Niña-related GMSL drop and estimate the frequency of such an event to be about only once in every 75 years. In addition to ENSO, major volcanic eruptions are found to be a key driver of interannual variability. Associated GMSL variability contrasts with that of ENSO as TWS and PW anomalies initially offset the drop due to OHC reductions but short-lived relative to them. Furthermore, responses up to 25 mm are estimated for the largest eruptions of the Last Millennium.« less

Managing variability in decision making in swine growing-finishing units.

PubMed

Agostini, Piero da Silva; Manzanilla, Edgar Garcia; de Blas, Carlos; Fahey, Alan G; da Silva, Caio Abercio; Gasa, Josep

2015-01-01

Analysis of data collected from pig farms may be useful to understand factors affecting pig health and productive performance. However, obtaining these data and drawing conclusions from them can be done at different levels and presents several challenges. In the present study, information from 688 batches of growing-finishing (GF) pigs (average initial and final body weight of 19.1 and 108.5 kg respectively) from 404 GF farms integrated in 7 companies was obtained between July 2008 and July 2010 in Spain by survey. Management and facility factors associated with feed conversion ratio (FCR) and mortality were studied by multiple linear regression analysis in each single company (A to G) and in an overall database (OD). Factors studied were geographic location of the farm, trimester the pigs entered the farm, breed of sire and sex segregation in pens (BREGENSEG), use of circovirus vaccine, number of origins the pigs were obtained from, age of the farm, percentage of slatted floor, type of feeder, drinker and ventilation, number of phases and form of feed, antibiotic administration system, water source, and number and initial weight of pigs. In two or more companies studied and/or in OD, the trimester when pigs were placed in the farm, BREGENSEG, number of origins of the pigs, age of the farm and initial body weight were factors associated with FCR. Regarding mortality, trimester of placement, number of origins of the pigs, water source in the farm, number of pigs placed and the initial body weight were relevant factors. Age of the farm, antibiotic administration system, and water source were only provided by some of the studied companies and were not included in the OD model, however, when analyzed in particular companies these three variables had an important effect and may be variables of interest in companies that do not record them. Analysing data collected from farms at different levels helps better understand factors associated with productive performance of pig herds. Out of the studied factors trimester of placement and number of origins of the pigs were the most relevant factors associated with FCR and mortality.

Evaluation of outcome and prognostic factors for dogs living greater than one year after diagnosis of osteosarcoma: 90 cases (1997–2008)

PubMed Central

Culp, William T. N.; Olea-Popelka, Francisco; Sefton, Jennifer; Aldridge, Charles F.; Withrow, Stephen J.; Lafferty, Mary H.; Rebhun, Robert B.; Kent, Michael S.; Ehrhart, Nicole

2015-01-01

Objective To evaluate clinical characteristics, outcome, and prognostic variables in a cohort of dogs surviving > 1 year after an initial diagnosis of osteosarcoma. Design Retrospective case series. Animals 90 client-owned dogs. Procedures Medical records for an 11-year period from 1997 through 2008 were reviewed, and patients with appendicular osteosarcoma that lived > 1 year after initial histopathologic diagnosis were studied. Variables including signalment, weight, serum alkaline phosphatase activity, tumor location, surgery, and adjuvant therapies were recorded. Median survival times were calculated by means of a Kaplan-Meier survival function. Univariate analysis was conducted to compare the survival function for categorical variables, and the Cox proportional hazard model was used to evaluate the likelihood of death > 1 year after diagnosis on the basis of the selected risk factors. Results 90 dogs met the inclusion criteria; clinical laboratory information was not available in all cases. Median age was 8.2 years (range, 2.7 to 13.3 years), and median weight was 38 kg (83.6 lb; range, 21 to 80 kg [46.2 to 176 lb]). Serum alkaline phosphatase activity was high in 29 of 60 (48%) dogs. The most common tumor location was the distal portion of the radius (54/90 [60%]). Eighty-nine of 90 (99%) dogs underwent surgery, and 78 (87%) received chemotherapy. Overall, 49 of 90 (54%) dogs developed metastatic disease. The median survival time beyond 1 year was 243 days (range, 1 to 1,899 days). Dogs that developed a surgical-site infection after limb-sparing surgery had a significantly improved prognosis > 1 year after osteosarcoma diagnosis, compared with dogs that did not develop infections. Conclusions and Clinical Relevance Results of the present study indicated that dogs with an initial diagnosis of osteosarcoma that lived > 1 year had a median survival time beyond the initial year of approximately 8 months. As reported previously, the development of a surgical-site infection in dogs undergoing a limb-sparing surgery significantly affected prognosis and warrants further study. PMID:25356715

Unraveling the Links Between the Initiation of Ventilation and Brain Injury in Preterm Infants

PubMed Central

Barton, Samantha K.; Tolcos, Mary; Miller, Suzie L.; Roehr, Charles C.; Schmölzer, Georg M.; Davis, Peter G.; Moss, Timothy J. M.; LaRosa, Domenic A.; Hooper, Stuart B.; Polglase, Graeme R.

2015-01-01

The initiation of ventilation in the delivery room is one of the most important but least controlled interventions a preterm infant will face. Tidal volumes (V T) used in the neonatal intensive care unit are carefully measured and adjusted. However, the V Ts that an infant receives during resuscitation are usually unmonitored and highly variable. Inappropriate V Ts delivered to preterm infants during respiratory support substantially increase the risk of injury and inflammation to the lungs and brain. These may cause cerebral blood flow instability and initiate a cerebral inflammatory cascade. The two pathways increase the risk of brain injury and potential life-long adverse neurodevelopmental outcomes. The employment of new technologies, including respiratory function monitors, can improve and guide the optimal delivery of V Ts and reduce confounders, such as leak. Better respiratory support in the delivery room has the potential to improve both respiratory and neurological outcomes in this vulnerable population. PMID:26618148

Cauchy problem as a two-surface based ‘geometrodynamics’

NASA Astrophysics Data System (ADS)

Rácz, István

2015-01-01

Four-dimensional spacetimes foliated by a two-parameter family of homologous two-surfaces are considered in Einstein's theory of gravity. By combining a 1 + (1 + 2) decomposition, the canonical form of the spacetime metric and a suitable specification of the conformal structure of the foliating two-surfaces, a gauge fixing is introduced. It is shown that, in terms of the chosen geometrically distinguished variables, the 1 + 3 Hamiltonian and momentum constraints can be recast into the form of a parabolic equation and a first order symmetric hyperbolic system, respectively. Initial data to this system can be given on one of the two-surfaces foliating the three-dimensional initial data surface. The 1 + 3 reduced Einstein's equations are also determined. By combining the 1 + 3 momentum constraint with the reduced system of the secondary 1 + 2 decomposition, a mixed hyperbolic-hyperbolic system is formed. It is shown that solutions to this mixed hyperbolic-hyperbolic system are also solutions to the full set of Einstein's equations provided that the 1 + 3 Hamiltonian constraint is solved on the initial data surface {{Σ }0} and the 1 + 2 Hamiltonian and momentum type expressions vanish on a world-tube yielded by the Lie transport of one of the two-surfaces foliating {{Σ }0} along the time evolution vector field. Whenever the foliating two-surfaces are compact without boundary in the spacetime and a regular origin exists on the time-slices—this is the location where the foliating two-surfaces smoothly reduce to a point—it suffices to guarantee that the 1 + 3 Hamiltonian constraint holds on the initial data surface. A short discussion on the use of the geometrically distinguished variables in identifying the degrees of freedom of gravity are also included. Dedicated to Zoltán Cseke on the occasion of his 70th birthday.

Prediction of Clinical Outcomes in Prenatal Hydronephrosis: Importance of Gravity Assisted Drainage.

PubMed

Sussman, Rachael D; Blum, Emily S; Sprague, Bruce M; Majd, Massoud; Rushton, H Gil; Pohl, Hans G

2017-03-01

In infants with SFU (Society for Fetal Urology) grade 3-4 congenital hydronephrosis, 99m Tc-mercaptoacetyltriglycine diuretic renography assesses differential function and drainage half-time. We routinely also include the percent of radiotracer drained after 30 minutes of diuresis as well as after 15 minutes with the patient in the upright position. We investigated whether any 1 or more of these parameters on initial diuretic renography predicts persistent or worsening drainage parameters. Infants 6 months or younger with grade 3-4 congenital hydronephrosis who presented between January 2009 and December 2014 were identified from billing data and included in analysis if they underwent at least 1 baseline diuretic renography. Those with structural anomalies were excluded from study. Baseline and followup differential function, diuresis half-time, clearance at 30 minutes and clearance with the patient upright were abstracted and comparisons were made between those with initially indeterminate diuresis half-time who underwent pyeloplasty vs those showing spontaneous improvement. A total of 74 patients (82 renal units) with presumed ureteropelvic junction obstruction met inclusion/exclusion criteria. All 10 renal units with initial diuresis half-time less than 5 minutes resolved spontaneously and all 25 renal units with initial diuresis half-time greater than 75 minutes underwent pyeloplasty. Therefore, we defined the indeterminate group as the 47 renal units with initial half-time between 5 and 75 minutes. Of those 47 renal units with indeterminate initial diuresis half-time 23 (47%) underwent pyeloplasty and 25 (53%) resolved spontaneously. Indications for pyeloplasty included worsening in 17 cases, persistent obstruction in 4 and urinary tract infection in 1. Among renal units with indeterminate drainage clearance while upright and clearance at 30 minutes were the only variables that differed significantly between surgical cases and those that resolved spontaneously. Radiotracer clearance with the patient upright and clearance at 30 minutes are more predictive of surgical management than diuresis half-time or differential function for renal units with indeterminate drainage. They should be included in the standard assessment of ureteropelvic junction obstruction. Copyright © 2017 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Longitudinal assessment of optical quality and intraocular scattering using the double-pass instrument in normal eyes and eyes with short tear breakup time.

PubMed

Kobashi, Hidenaga; Kamiya, Kazutaka; Yanome, Kyohei; Igarashi, Akihito; Shimizu, Kimiya

2013-01-01

To assess the longitudinal changes in optical quality including intraocular scattering in normal eyes and eyes with short tear breakup time (TBUT). We prospectively examined twenty eyes of 20 healthy subjects, and age-matched twenty eyes of 20 short TBUT subjects. The modulation transfer function (MTF) cutoff frequency, the Strehl ratio, and the objective scattering index (OSI) were quantitatively assessed using an Optical Quality Analysis System. We investigated the changes in these variables measured consecutively at the initial examination, 5, and 10 seconds without blinking. We also compared these variables in eyes with short TBUT with those in normal eyes. No significant differences in the MTF cutoff frequency, Strehl ratio, or OSI were detected over a 10-second period in normal eyes. These variables also became significantly degraded even over a 5-second period in eyes with short TBUT (p<0.01). We found significant differences in these variables at 5 and 10 seconds (p<0.05), but none immediately after the blink between normal and short TBUT eyes. Optical quality including intraocular scattering deteriorated significantly with time in eyes with short TBUT, whereas we found significant differences over a 10-second period in normal eyes. Eyes with short TBUT showed greater deterioration in optical quality after the blink than normal eyes. The longitudinal assessment of optical quality may be effective in distinguishing eyes with short TBUT from normal eyes.

Amniotic fluid index predicts the relief of variable decelerations after amnioinfusion bolus.

PubMed

Spong, C Y; McKindsey, F; Ross, M G

1996-10-01

Our purpose was to determine whether intrapartum amniotic fluid index before amnioinfusion can be used to predict response to therapeutic amnioinfusion. Intrapartum patients (n = 85) with repetitive variable decelerations in fetal heart rate that necessitated amnioinfusion (10 ml/min for 60 minutes) underwent determination of amniotic fluid index before and after bolus amnioinfusion. The fetal heart tracing was scored (scorer blinded to amniotic fluid index values) for number and characteristics of variable decelerations before and 1 hour after initiation of amnioinfusion. The amnioinfusion was considered successful if it resulted in a decrease of > or = 50% in total number of variable decelerations or a decrease of > or = 50% in the rate of atypical or severe variable decelerations after administration of the bolus. Spontaneous vaginal births before completion of administration of the bolus (n = 18) were excluded from analysis. The probability of success of amnioinfusion in relation to amniotic fluid index was analyzed with the chi(2) test for progressive sequence. The mean amniotic fluid index before amnioinfusion was 6.2 +/- 3.3 cm. An amniotic fluid index of < or = 5 cm was present in 40% of patients (27/67), and an amniotic fluid index of < or = 8 cm was present in 72% of patients (48/67). The probability of success of amnioinfusion decreased with increasing amniotic fluid index before amnioinfusion (76% [16/21] when initial amniotic fluid index was 0 to 4 cm, 63% [17/27] when initial amniotic fluid index was 4 to 8 cm, 44% [7/16] when initial amniotic fluid index was 8 to 12 cm, and 33% [1/3] when initial amniotic fluid index was > 12 cm, p = 0.03). The incidence of nuchal cords or true umbilical cord knots increased in relation to amniotic fluid index before amnioinfusion. Amniotic fluid index before amnioinfusion can be used to predict the success of amnioinfusion for relief of variable decelerations in fetal heart rate. Failure of amnioinfusion at a high amniotic fluid index before amnioinfusion may be explained by the increased prevalence of nuchal cords or true knots in the umbilical cord.

A novel model incorporating two variability sources for describing motor evoked potentials

PubMed Central

Goetz, Stefan M.; Luber, Bruce; Lisanby, Sarah H.; Peterchev, Angel V.

2014-01-01

Objective Motor evoked potentials (MEPs) play a pivotal role in transcranial magnetic stimulation (TMS), e.g., for determining the motor threshold and probing cortical excitability. Sampled across the range of stimulation strengths, MEPs outline an input–output (IO) curve, which is often used to characterize the corticospinal tract. More detailed understanding of the signal generation and variability of MEPs would provide insight into the underlying physiology and aid correct statistical treatment of MEP data. Methods A novel regression model is tested using measured IO data of twelve subjects. The model splits MEP variability into two independent contributions, acting on both sides of a strong sigmoidal nonlinearity that represents neural recruitment. Traditional sigmoidal regression with a single variability source after the nonlinearity is used for comparison. Results The distribution of MEP amplitudes varied across different stimulation strengths, violating statistical assumptions in traditional regression models. In contrast to the conventional regression model, the dual variability source model better described the IO characteristics including phenomena such as changing distribution spread and skewness along the IO curve. Conclusions MEP variability is best described by two sources that most likely separate variability in the initial excitation process from effects occurring later on. The new model enables more accurate and sensitive estimation of the IO curve characteristics, enhancing its power as a detection tool, and may apply to other brain stimulation modalities. Furthermore, it extracts new information from the IO data concerning the neural variability—information that has previously been treated as noise. PMID:24794287

Exercise systolic blood pressure variability is associated with increased risk for new-onset hypertension among normotensive adults.

PubMed

Berger, Assaf; Grossman, Ehud; Katz, Moshe; Kivity, Shaye; Klempfner, Robert; Segev, Shlomo; Goldenberg, Ilan; Sidi, Yehezkel; Maor, Elad

2016-06-01

Both resting blood pressure (BP) variability and exercise BP previously showed association with incident hypertension. The aim of the present study was to examine whether visit-to-visit variability in exercise systolic blood pressure (SBP) can predict the risk for new-onset hypertension among normotensive adults. We investigated 6546 normotensive men and women who were annually screened in a tertiary medical center and completed treadmill exercise tests at each visit. Based on the initial three baseline annual visits, long-term intervisit variability of exercise SBP among the three tests was measured using standard deviation (SD) and coefficient of variation for each participant. The rate of newly diagnosed hypertension was measured in different variability levels during 6 ± 3 years of follow-up. Multivariate analysis adjusted for various clinical factors, including resting BP, showed that each 5 mm Hg rise in the SD of exercise SBP resulted in a significant 5% increase in the risk for the development of future hypertension (P = .015). Subjects in the upper exercise SBP SD variability tertile had a 28% (P = .007) increased risk for hypertension during follow-up, as compared with those in the lowest tertile. Similar results were achieved for the assessment of coefficient of variation of exercise SBP. In conclusion, visit-to-visit variability in exercise SBP can predict the development of future hypertension among normotensive individuals. Copyright © 2016 American Society of Hypertension. Published by Elsevier Inc. All rights reserved.

Further evaluation of leisure items in the attention condition of functional analyses.

PubMed

Roscoe, Eileen M; Carreau, Abbey; MacDonald, Jackie; Pence, Sacha T

2008-01-01

Research suggests that including leisure items in the attention condition of a functional analysis may produce engagement that masks sensitivity to attention. In this study, 4 individuals' initial functional analyses indicated that behavior was maintained by nonsocial variables (n = 3) or by attention (n = 1). A preference assessment was used to identify items for subsequent functional analyses. Four conditions were compared, attention with and without leisure items and control with and without leisure items. Following this, either high- or low-preference items were included in the attention condition. Problem behavior was more probable during the attention condition when no leisure items or low-preference items were included, and lower levels of problem behavior were observed during the attention condition when high-preference leisure items were included. These findings suggest how preferred items may hinder detection of behavioral function.

Sexual possibility situations and sexual behaviors among young adolescents: the moderating role of protective factors.

PubMed

DiLorio, Colleen; Dudley, William N; Soet, Johanna E; McCarty, Frances

2004-12-01

To examine sexual possibility situations (SPS) and protective practices associated with involvement in intimate sexual behaviors and the initiation of sexual intercourse among young adolescents and to determine if protective factors moderate the relationship between SPS and sexual behaviors. Data for these analyses were obtained from the baseline assessment for adolescents conducted as part of an HIV prevention study called "Keepin' it R.E.A.L.!" The study was conducted with a community-based organization (CBO) in an urban area serving a predominantly African-American population. In addition to items assessing SPS, intimate sexual behaviors, and initiation of sexual intercourse, adolescents provided information on the following protective factors: educational goals, self-concept, future time perspective, orientation to health, self-efficacy, outcome expectations, parenting, communication, values, and prosocial activities. Background personal information, including age and gender, was also collected. The analyses were conducted on data from 491 predominantly African-American adolescents, 61% of whom were boys. Variables were combined to form SPS and protective indices that were used in the first set of regression analyses. In a second set of analyses, the indices were unbundled and individual variables were entered into regression analyses. Both SPS and protective indices explained significant portions of variance in intimate sexual behaviors, and the SPS index explained a significant portion of variance in the initiation of sexual intercourse. The regression analysis using the unbundled SPS and protective factors revealed the following statistically significant predictors for intimate sexual behaviors: age, gender, time alone with groups of peers, time alone with a member of the opposite sex, behavior self-concept, popularity self-concept, self-efficacy for abstinence, outcome expectations for abstinence, parental control, personal values, and parental values. A similar regression analysis revealed that age, time alone with a member of the opposite sex, and personal values were significant predictors of initiation of sexual intercourse. These results provide evidence for the important role of protective factors in explaining early involvement in sexual behaviors and show that protective factors extend beyond personal characteristics to include both familial and peer factors.

Production, Stocks and Characteristics of Wildfire Charcoal in Canadian Boreal Forests; a Preliminary Synthesis

NASA Astrophysics Data System (ADS)

Preston, C. M.; Simard, M.

2016-12-01

Crowning wildfires are a major driver of carbon stocks and ecosystem development in Canadian boreal forests, but there is insufficient information to incorporate pyrogenic carbon (PyC) into models and management strategies. Data comparison is challenging because of varied experimental design, and studies are often limited to forest floor; nonetheless we have attempted a synthesis limited to visually determined PyC, hereafter designated "charcoal". Sources include our study of amounts, depth distribution (forest floor plus variable amounts of upper mineral soil) and chemical properties of charcoal (>2 mm) from a fire chronosequence in the Abitibi region of Quebec (51 jack pine (Pinus banksiana) and black spruce (Picea mariana) sites, 24 to 2355 years since fire). Complete charcoal production of 7900 kg/ha (forest floor, down wood, standing stems) was determined from an experimental crownfire in jack pine near Fort Providence (NWT) in 2012. Published data were assembled mainly from boreal conifer studies, but using more disparate sources for production, plus laboratory charring studies. Typical findings include high spatial variability, with depth distributions often showing a maximum around the organic-mineral interface. Stocks varied widely (up to ca. 5500 kg/ha), with little initial discernable trend with time, but were much lower in the few older sites (>700y). Total C and N were widely scattered for younger samples, but older samples were mainly 500-600 g C/kg with C/N values around 100. Similarly, carbon-13 NMR spectra show wider variation in young samples, with the oldest samples being highly aromatic. These initial variations are consistent with field reports of highly variable temperatures and duration of charring and many laboratory studies. As a starting point, it may be possibly suggested that a boreal crowning wildfire might produce some 5000-10000 kg/ha of charred material of 550-650 g C/kg, with half to two-thirds on forest floor and down wood and most of the rest on standing stems. Our synthesis mainly highlights future research needs, including more measurements on stems and down wood and chemical analysis of the black carbon component of charcoal.

Surgical Versus Nonsurgical Management of Rotator Cuff Tears: Predictors of Treatment Allocation.

PubMed

Kweon, Christopher; Gagnier, Joel J; Robbins, Christopher B; Bedi, Asheesh; Carpenter, James E; Miller, Bruce S

2015-10-01

Rotator cuff tears are a common shoulder disorder resulting in significant disability to patients and financial burden on the health care system. While both surgical and nonsurgical management are accepted treatment options, there is a paucity of data to support a treatment algorithm for care providers. Defining variables to guide treatment allocation may be important for patient education and counseling, as well as to deliver the most efficient care plan at the time of presentation. To identify independent variables at the time of initial clinical presentation that are associated with preferred allocation to surgical versus nonsurgical management for patients with known full-thickness rotator cuff tears. Case control study; Level of evidence, 3. A total of 196 consecutive adult patients with known full-thickness rotator cuff tears were enrolled into a prospective cohort study. Robust data were collected for each subject at baseline, including age, sex, body mass index (BMI), shoulder activity score, smoking status, size of cuff tear, duration of symptoms, functional comorbidity index, the American Shoulder and Elbow Surgeons (ASES) score, the Western Ontario Rotator Cuff index (WORC), and the Veterans Rand 12-Item Health Survey (VR-12). Logistic regression was performed to identify variables associated with treatment allocation, and the corresponding odds ratios were calculated. Of the 196 patients enrolled, 112 underwent surgical intervention and 84 nonoperative management. With covariates controlled for, significant baseline patient characteristics predictive of eventual allocation to surgical treatment included younger age, lower BMI, and durations of symptoms less than 1 year. Increasing age, higher BMI, and duration of symptoms longer than 1 year were predictive of nonsurgical treatment. Factors that were not associated with treatment allocation included sex, tear size, functional comorbidity score, or any of the patient-derived outcome scores at presentation (ASES, WORC, VR-12, shoulder activity score). Patient demographics at the time of initial presentation for a symptomatic rotator cuff tear are more predictive of treatment allocation to a surgical or nonoperative approach than the patient-derived outcome scores for activity level and shoulder disability. Further study is warranted to help define appropriate indications for treatment allocation in patients with rotator cuff tears. © 2015 The Author(s).

Parental Decisional Regret after Primary Distal Hypospadias Repair: Family and Surgery Variables, and Repair Outcomes.

PubMed

Ghidini, Filippo; Sekulovic, Sasa; Castagnetti, Marco

2016-03-01

Decisional regret is defined as distress after making a health care choice and can be an issue for parents electing distal hypospadias repair for their sons. We assessed the influence on decisional regret of variables related to the family, surgery and outcomes. Charts for 372 patients undergoing primary distal hypospadias repair between 2005 and 2012 were reviewed, and validated questionnaires, including the Decisional Regret Scale, Pediatric Penile Perception Score and Dysfunctional Voiding and Incontinence Scoring System, were administered to parents. Data were available for 172 of 372 families (response rate 46.2%). Of 323 parents 128 (39.6%) presented with moderately strong decisional regret, with good agreement within couples. Predictors of decisional regret included intermediate parental educational level (OR 3.19, 95% CI 1.52-6.69), patient not being the first born (OR 2.01, 95% CI 1.07-3.78), family history of hypospadias (OR 4.42, 95% CI 1.96-9.97), initial desire to avoid surgery (OR 2.07, 95% CI 1.04-4.12), younger age at followup (OR 0.81, 95% CI 0.72-0.91), presence of lower urinary tract symptoms (OR 4.92, 95% CI 1.53-15.81) and lower Pediatric Penile Perception Score (OR 0.86, 95% CI 0.75-0.99). Decisional regret was unrelated to parental desire to avoid circumcision, surgical variables, development of complications and duration of followup. Decisional regret is a problem in a significant proportion of parents electing distal hypospadias repair for their sons. In our experience family variables seemed to be predictors of decisional regret, while surgical variables did not. Predictors of decisional regret included worse parental perception of penile appearance and the presence of lower urinary tract symptoms. However, the latter could be unrelated to surgery. Irrespective of the duration of followup, decisional regret seems decreased in parents of older patients. Copyright © 2016 American Urological Association Education and Research, Inc. Published by Elsevier Inc. All rights reserved.

Characterizing uncertainty and variability in physiologically based pharmacokinetic models: state of the science and needs for research and implementation.

PubMed

Barton, Hugh A; Chiu, Weihsueh A; Setzer, R Woodrow; Andersen, Melvin E; Bailer, A John; Bois, Frédéric Y; Dewoskin, Robert S; Hays, Sean; Johanson, Gunnar; Jones, Nancy; Loizou, George; Macphail, Robert C; Portier, Christopher J; Spendiff, Martin; Tan, Yu-Mei

2007-10-01

Physiologically based pharmacokinetic (PBPK) models are used in mode-of-action based risk and safety assessments to estimate internal dosimetry in animals and humans. When used in risk assessment, these models can provide a basis for extrapolating between species, doses, and exposure routes or for justifying nondefault values for uncertainty factors. Characterization of uncertainty and variability is increasingly recognized as important for risk assessment; this represents a continuing challenge for both PBPK modelers and users. Current practices show significant progress in specifying deterministic biological models and nondeterministic (often statistical) models, estimating parameters using diverse data sets from multiple sources, using them to make predictions, and characterizing uncertainty and variability of model parameters and predictions. The International Workshop on Uncertainty and Variability in PBPK Models, held 31 Oct-2 Nov 2006, identified the state-of-the-science, needed changes in practice and implementation, and research priorities. For the short term, these include (1) multidisciplinary teams to integrate deterministic and nondeterministic/statistical models; (2) broader use of sensitivity analyses, including for structural and global (rather than local) parameter changes; and (3) enhanced transparency and reproducibility through improved documentation of model structure(s), parameter values, sensitivity and other analyses, and supporting, discrepant, or excluded data. Longer-term needs include (1) theoretical and practical methodological improvements for nondeterministic/statistical modeling; (2) better methods for evaluating alternative model structures; (3) peer-reviewed databases of parameters and covariates, and their distributions; (4) expanded coverage of PBPK models across chemicals with different properties; and (5) training and reference materials, such as cases studies, bibliographies/glossaries, model repositories, and enhanced software. The multidisciplinary dialogue initiated by this Workshop will foster the collaboration, research, data collection, and training necessary to make characterizing uncertainty and variability a standard practice in PBPK modeling and risk assessment.

A novel approach for evaluating the impact of fixed variables on photovoltaic (PV) solar installations using enhanced meta data analysis among higher education institutions in the United States

NASA Astrophysics Data System (ADS)

De Hoyos, Diane N.

The global demand for electric energy has continuously increased over the last few decades. Some mature, alternative generation methods are wind, power, photovoltaic panels, biogas and fuel cells. In order to find alternative sources of energy to aid in the reduction of our nation's dependency on non-renewable fuels, energy sources include the use of solar energy panels. The intent of these initiatives is to provide substantial energy savings and reduce dependence on the electrical grid and net metering savings during the peak energy-use hours. The focus of this study explores and provides a clearer picture of the adoption of solar photovoltaic technology in institutions of higher education. It examines the impact of different variables associated with a photovoltaic installation in an institutions of higher education in the United States on the production generations for universities. Secondary data was used with permission from the Advancement of Suitability in Higher Education (AASHE). A multiple regression analysis was performed to determine the impact of different variables on the energy generation production. A Meta Data transformation analysis offered a deeper investigation into the impact of the variables on the photovoltaic installations. Although a review of a significant number of journal articles, dissertations and thesis in the area of photovoltaic solar installations are available, there were limited studies of actual institutions of higher education with the significant volume of institutions. However a study where the database included a significant number of data variables is unique and provides a researcher the opportunity to investigate different facets of a solar installation. The data of the installations ranges from 1993-2015. Included in this observation are the researcher's experience both in the procurement industry and as a team member of a solar institution of higher education in the southern portion of the United States.

A Prospective Study on the Influence of Scholastic Factors on the Prevalence and Initiation of Illicit Drug Misuse in Adolescence.

PubMed

Zubak, Zoran; Zenic, Natasa; Ostojic, Ljerka; Zubak, Ivana; Pojskic, Haris

2018-04-27

This study aimed to prospectively investigate the scholastic factors related to illicit drug misuse (IDM) and the initiation of IDM among older adolescents from Bosnia and Herzegovina. This 2-year prospective study included 436 participants (202 females), who were an average of 16 years old at the beginning of the study (baseline). The participants were tested at baseline and follow-up (20 months later). The predictors included variables of scholastic-achievement (grade point average, school absences, unexcused absences and behavioral grade). The criteria were: (i) IDM at baseline; (ii) IDM at follow-up; and (iii) initiation of IDM over the study course. Results : Logistic regression indicated increased odds of IDM in adolescents who were more frequent absent from school (baseline: Odds Ratio (OR): 3.73, 95% Confidence Interval (CI): 2.12⁻6.57; follow-up: OR: 2.91, 95% CI: 1.90⁻4.65). The lower grade point average and more unexcused absences were evidenced for adolescents who consumed drugs on follow-up (OR: 1.67, 95% CI: 1.11⁻2.51; OR: 1.74, 95% CI: 1.30⁻2.32 for grade point average and unexcused absences, respectively). Initiation of IDM was predicted by frequent absences from school (OR: 2.2, 95% CI: 1.3⁻3.8), and lower behavioral grades (OR: 1.9, 95% CI: 1.2⁻3.3). The findings confirmed strong correlations between scholastic failure and IDM. Absences from school and lower behavioral grades at baseline were predictive of the initiation of IDM in older adolescents.

Properties of Zero-Free Transfer Function Matrices

NASA Astrophysics Data System (ADS)

D. O. Anderson, Brian; Deistler, Manfred

Transfer functions of linear, time-invariant finite-dimensional systems with more outputs than inputs, as arise in factor analysis (for example in econometrics), have, for state-variable descriptions with generic entries in the relevant matrices, no finite zeros. This paper gives a number of characterizations of such systems (and indeed square discrete-time systems with no zeros), using state-variable, impulse response, and matrix-fraction descriptions. Key properties include the ability to recover the input values at any time from a bounded interval of output values, without any knowledge of an initial state, and an ability to verify the no-zero property in terms of a property of the impulse response coefficient matrices. Results are particularized to cases where the transfer function matrix in question may or may not have a zero at infinity or a zero at zero.

A hybrid model for traffic flow and crowd dynamics with random individual properties.

PubMed

Schleper, Veronika

2015-04-01

Based on an established mathematical model for the behavior of large crowds, a new model is derived that is able to take into account the statistical variation of individual maximum walking speeds. The same model is shown to be valid also in traffic flow situations, where for instance the statistical variation of preferred maximum speeds can be considered. The model involves explicit bounds on the state variables, such that a special Riemann solver is derived that is proved to respect the state constraints. Some care is devoted to a valid construction of random initial data, necessary for the use of the new model. The article also includes a numerical method that is shown to respect the bounds on the state variables and illustrative numerical examples, explaining the properties of the new model in comparison with established models.

The Lunar Atmosphere and Dust Environment Explorer (LADEE): Initial Science Results

NASA Technical Reports Server (NTRS)

Elphic, R. C.; Hine, B.; Delory, G. T.; Salute, J. S.; Noble, S.; Colaprete, A.; Horanyi, M.; Mahaffy, P.

2014-01-01

On September 6, 2013, a nearperfect launch of the first Minotaur V rocket successfully carried NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE) into a higheccentricity geocentric orbit. The launch, from NASA's Wallops Flight Facility in Virginia, was visible from much of the eastern seaboard. Over the next 30 days, LADEE performed three phasing orbits, with near-perfect maneuvers that placed apogee at ever higher altitudes in preparation for rendezvous with the Moon. LADEE arrived at the Moon on October 6, 2013, during the government shutdown. LADEE's science objectives are twofold: (1) Determine the composition of the lunar atmosphere, investigate processes controlling its distribution and variability, including sources, sinks, and surface interactions; (2) Characterize the lunar exospheric dust environment, measure its spatial and temporal variability, and effects on the lunar atmosphere, if any.

Hamiltonian models for the propagation of irrotational surface gravity waves over a variable bottom

NASA Astrophysics Data System (ADS)

Compelli, A.; Ivanov, R.; Todorov, M.

2017-12-01

A single incompressible, inviscid, irrotational fluid medium bounded by a free surface and varying bottom is considered. The Hamiltonian of the system is expressed in terms of the so-called Dirichlet-Neumann operators. The equations for the surface waves are presented in Hamiltonian form. Specific scaling of the variables is selected which leads to approximations of Boussinesq and Korteweg-de Vries (KdV) types, taking into account the effect of the slowly varying bottom. The arising KdV equation with variable coefficients is studied numerically when the initial condition is in the form of the one-soliton solution for the initial depth. This article is part of the theme issue 'Nonlinear water waves'.

Towards the Prediction of Decadal to Centennial Climate Processes in the Coupled Earth System Model

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

Liu, Zhengyu; Kutzbach, J.; Jacob, R.

2011-12-05

In this proposal, we have made major advances in the understanding of decadal and long term climate variability. (a) We performed a systematic study of multidecadal climate variability in FOAM-LPJ and CCSM-T31, and are starting exploring decadal variability in the IPCC AR4 models. (b) We develop several novel methods for the assessment of climate feedbacks in the observation. (c) We also developed a new initialization scheme DAI (Dynamical Analogue Initialization) for ensemble decadal prediction. (d) We also studied climate-vegetation feedback in the observation and models. (e) Finally, we started a pilot program using Ensemble Kalman Filter in CGCM for decadalmore » climate prediction.« less

The moderating effects of culture on peer deviance and alcohol use among high-risk African-American Adolescents.

PubMed

Nasim, Aashir; Belgrave, Faye Z; Jagers, Robert J; Wilson, Karen D; Owens, Kristal

2007-01-01

African-American adolescents have lower rates of alcohol consumption than White youth. However, African-American youth suffer disproportionately more adverse social, mental, and physical health outcomes related to alcohol use. Affiliating with negative peers is a risk factor for alcohol initiation and consumption. Cultural variables have shown moderating effects against other risk factors for African-American youth and therefore were the focus of this study. Specifically, we tested whether three culturally-relevant variables, Africentric beliefs, religiosity, and ethnic identity were promotive or protective for alcohol initiation and use within the context of negative peer affiliations. The sample consisted of 114 at-risk African-American adolescents whose ages ranged from 13 to 20. Participants were administered a questionnaire with measures of alcohol initiation and use, peer risk behaviors, ethnic identity, Africentric beliefs, religiosity, and demographic items. Peer risk behaviors accounted for significant percentages of the variance in age of alcohol initiation, lifetime use, and current and heavy alcohol use after adjusting for age and gender. Cultural variables showed both promotive and protective effects. Africentric beliefs were promotive of delayed alcohol initiation, whereas both Africentrism and religiosity moderated peer risk behaviors effect on alcohol initiation. Africentric beliefs were also inversely related to lifetime alcohol use revealing a promotive effect. Moreover, there were significant protective effects of ethnic identity and religiosity on heavy alcohol consumption. One implication of these findings is that prevention programs that infuse cultural values and practices such as Africentrism, ethnic identity, and religiosity may delay alcohol initiation and reduce use especially for youth with high risk peers.

Early smoking initiation and associated factors among in-school male and female adolescents in seven African countries.

PubMed

Peltzer, K

2011-09-01

This report examines the prevalence and common correlates of early smoking initiation among male and female school children across seven African countries. The total sample included 17,725 school children aged 13 to 15 years from nationally representative samples in seven African countries. Univariate and multivariate analyses were conducted to assess the relationship between early smoking initiation, health compromising behaviours, mental distress, protective factors and socio-economic status variables. Overall 15.5% had experienced smoking initiation before age 14, with the percentages 20.1% among boys and 10.9% among girls. In multivariable analysis, early smoking initiation was among boys associated with ever drunk from alcohol use (OR = 4.73, p = 0.001), ever used drugs (OR = 2.36, p = 0.04) and ever had sex (OR = 1.63, p = 0.04). Among girls, it was associated with higher education (OR = 5.77, p = 0.001), ever drunk from alcohol use (OR = 4.76, p = 0.002), parental or guardian tobacco use (OR = 2.83, p = 0.001) and suicide ideation (OR = 2.05, p = 0.02). The study found a high prevalence of early smoking initiation among 13-15 year-olds in seven African countries. Various risk factors have been identified in boys and girls who initiate smoking before age 14, forming a distinct risk group in this setting. Specific interventions are needed for boys and girls in the preteen years, before smoking initiation.

Predictive factors for rebleeding and death in alcoholic cirrhotic patients with acute variceal bleeding: a multivariate analysis.

PubMed

Krige, Jake E J; Kotze, Urda K; Distiller, Greg; Shaw, John M; Bornman, Philippus C

2009-10-01

Bleeding from esophageal varices is a leading cause of death in alcoholic cirrhotic patients. The aim of the present single-center study was to identify risk factors predictive of variceal rebleeding and death within 6 weeks of initial treatment. Univariate and multivariate analyses were performed on 310 prospectively documented alcoholic cirrhotic patients with acute variceal hemorrhage (AVH) who underwent 786 endoscopic variceal injection treatments between January 1984 and December 2006. All injections were administered during the first 6 weeks after the patients were treated for their first variceal bleed. Seventy-five (24.2%) patients experienced a rebleed, 38 within 5 days of the initial treatment and 37 within 6 weeks of their initial treatment. Of the 15 variables studied and included in a multivariate analysis using a logistic regression model, a bilirubin level >51 mmol/l and transfusion of >6 units of blood during the initial hospital admission were predictors of variceal rebleeding within the first 6 weeks. Seventy-seven (24.8%) patients died, 29 (9.3%) within 5 days and 48 (15.4%) between 6 and 42 days after the initial treatment. Stepwise multivariate logistic regression analysis showed that six variables were predictors of death within the first 6 weeks: encephalopathy, ascites, bilirubin level >51 mmol/l, international normalized ratio (INR) >2.3, albumin <25 g/l, and the need for balloon tube tamponade. Survival was influenced by the severity of liver failure, with most deaths occurring in Child-Pugh grade C patients. Patients with AVH and encephalopathy, ascites, bilirubin levels >51 mmol/l, INR >2.3, albumin <25 g/l and who require balloon tube tamponade are at increased risk of dying within the first 6 weeks. Bilirubin levels >51 mmol/l and transfusion of >6 units of blood were predictors of variceal rebleeding.

Instructions to "put the phone down" do not improve the quality of bystander initiated dispatcher-assisted cardiopulmonary resuscitation.

PubMed

Brown, Todd B; Saini, Devashish; Pepper, Tracy; Mirza, Muzna; Nandigam, Hari Krishna; Kaza, Niroop; Cofield, Stacey S

2008-02-01

The quality of early bystander CPR appears important in maximizing survival. This trial tests whether explicit instructions to "put the phone down" improve the quality of bystander initiated dispatch-assisted CPR. In a randomized, double-blinded, controlled trial, subjects were randomized to a modified version of the Medical Priority Dispatch System (MPDS) version 11.2 protocol or a simplified protocol, each with or without instruction to "put the phone down" during CPR. Data were recorded from a Laerdal Resusci Anne Skillreporter manikin. A simulated emergency medical dispatcher, contacted by cell phone, delivered standardized instructions. Primary outcome measures included chest compression rate, depth, and the proportion of compressions without error, with correct hand position, adequate depth, and total release. Time was measured in two distinct ways: time required for initiation of CPR and total amount of time hands were off the chest during CPR. Proportions were analyzed by Wilcoxon rank sum tests and time variables with ANOVA. All tests used a two-sided alpha-level of 0.05. Two hundred and fifteen subjects were randomized-107 in the "put the phone down" instruction group and 108 in the group without "put the phone down" instructions. The groups were comparable across demographic and experiential variables. The additional instruction to "put the phone down" had no effect on the proportion of compressions administered without error, with the correct depth, and with the correct hand position. Likewise, "put the phone down" did not affect the average compression depth, the average compression rate, the total hands-off-chest time, or the time to initiate chest compressions. A statistically significant, yet trivial, effect was found in the proportion of compressions with total release of the chest wall. Instructions to "put the phone down" had no effect on the quality of bystander initiated dispatcher-assisted CPR in this trial.

Regional-scale brine migration along vertical pathways due to CO2 injection - Part 2: A simulated case study in the North German Basin

NASA Astrophysics Data System (ADS)

Kissinger, Alexander; Noack, Vera; Knopf, Stefan; Konrad, Wilfried; Scheer, Dirk; Class, Holger

2017-06-01

Saltwater intrusion into potential drinking water aquifers due to the injection of CO2 into deep saline aquifers is one of the hazards associated with the geological storage of CO2. Thus, in a site-specific risk assessment, models for predicting the fate of the displaced brine are required. Practical simulation of brine displacement involves decisions regarding the complexity of the model. The choice of an appropriate level of model complexity depends on multiple criteria: the target variable of interest, the relevant physical processes, the computational demand, the availability of data, and the data uncertainty. In this study, we set up a regional-scale geological model for a realistic (but not real) onshore site in the North German Basin with characteristic geological features for that region. A major aim of this work is to identify the relevant parameters controlling saltwater intrusion in a complex structural setting and to test the applicability of different model simplifications. The model that is used to identify relevant parameters fully couples flow in shallow freshwater aquifers and deep saline aquifers. This model also includes variable-density transport of salt and realistically incorporates surface boundary conditions with groundwater recharge. The complexity of this model is then reduced in several steps, by neglecting physical processes (two-phase flow near the injection well, variable-density flow) and by simplifying the complex geometry of the geological model. The results indicate that the initial salt distribution prior to the injection of CO2 is one of the key parameters controlling shallow aquifer salinization. However, determining the initial salt distribution involves large uncertainties in the regional-scale hydrogeological parameterization and requires complex and computationally demanding models (regional-scale variable-density salt transport). In order to evaluate strategies for minimizing leakage into shallow aquifers, other target variables can be considered, such as the volumetric leakage rate into shallow aquifers or the pressure buildup in the injection horizon. Our results show that simplified models, which neglect variable-density salt transport, can reach an acceptable agreement with more complex models.

Configuration optimization of space structures

NASA Technical Reports Server (NTRS)

Felippa, Carlos; Crivelli, Luis A.; Vandenbelt, David

1991-01-01

The objective is to develop a computer aid for the conceptual/initial design of aerospace structures, allowing configurations and shape to be apriori design variables. The topics are presented in viewgraph form and include the following: Kikuchi's homogenization method; a classical shape design problem; homogenization method steps; a 3D mechanical component design example; forming a homogenized finite element; a 2D optimization problem; treatment of volume inequality constraint; algorithms for the volume inequality constraint; object function derivatives--taking advantage of design locality; stiffness variations; variations of potential; and schematics of the optimization problem.

Parametric study of minimum converter loss in an energy-storage dc-to-dc converter

NASA Technical Reports Server (NTRS)

Wong, R. C.; Owen, H. A., Jr.; Wilson, T. G.

1982-01-01

Through a combination of analytical and numerical minimization procedures, a converter design that results in the minimum total converter loss (including core loss, winding loss, capacitor and energy-storage-reactor loss, and various losses in the semiconductor switches) is obtained. Because the initial phase involves analytical minimization, the computation time required by the subsequent phase of numerical minimization is considerably reduced in this combination approach. The effects of various loss parameters on the optimum values of the design variables are also examined.

Timing of Operative Debridement in Open Fractures.

PubMed

Rozell, Joshua C; Connolly, Keith P; Mehta, Samir

2017-01-01

The optimal treatment of open fractures continues to be an area of debate in the orthopedic literature. Recent research has challenged the dictum that open fractures should be debrided within 6 hours of injury. However, the expedient administration of intravenous antibiotics remains of paramount importance in infection prevention. Multiple factors, including fracture severity, thoroughness of debridement, time to initial treatment, and antibiotic administration, among other variables, contribute to the incidence of infection and complicate identifying an optimal time to debridement. Copyright © 2016 Elsevier Inc. All rights reserved.

SAPHO: What radiologists should know.

PubMed

Depasquale, R; Kumar, N; Lalam, R K; Tins, B J; Tyrrell, P N M; Singh, J; Cassar-Pullicino, V N

2012-03-01

SAPHO (synovitis, acne, pustulosis, hyperostosis, and osteitis) is an umbrella acronym for inflammatory clinical conditions whose common denominator is aseptic osteoarticular involvement with characteristic skin lesions. It involves all ages, can involve any skeletal site, and has variable imaging appearances depending on the stage/age of the lesion and imaging method. It mimics important differentials including infection and neoplasia. Awareness of the imaging features, especially in the spine, facilitates early diagnosis, prevents repeated biopsies, and avoids unnecessary surgery, while initiating appropriate treatment. Copyright © 2011 The Royal College of Radiologists. Published by Elsevier Ltd. All rights reserved.

The Lifespan of a Class of Smooth Spherically Symmetric Solutions of the Compressible Euler Equations with Variable Entropy in Three Space Dimensions

NASA Astrophysics Data System (ADS)

Godin, Paul

2005-09-01

We consider smooth three-dimensional spherically symmetric Eulerian flows of ideal polytropic gases with variable entropy, whose initial data are obtained by adding a small smooth perturbation with compact support to a constant state. Under a natural assumption, we obtain precise information on the asymptotic behavior of their lifespan when the size of the initial perturbation tends to 0. This is achieved by the construction and estimate of a suitable approximate flow.

Systematic review of statistically-derived models of immunological response in HIV-infected adults on antiretroviral therapy in Sub-Saharan Africa.

PubMed

Sempa, Joseph B; Ujeneza, Eva L; Nieuwoudt, Martin

2017-01-01

In Sub-Saharan African (SSA) resource limited settings, Cluster of Differentiation 4 (CD4) counts continue to be used for clinical decision making in antiretroviral therapy (ART). Here, HIV-infected people often remain with CD4 counts <350 cells/μL even after 5 years of viral load suppression. Ongoing immunological monitoring is necessary. Due to varying statistical modeling methods comparing immune response to ART across different cohorts is difficult. We systematically review such models and detail the similarities, differences and problems. 'Preferred Reporting Items for Systematic Review and Meta-Analyses' guidelines were used. Only studies of immune-response after ART initiation from SSA in adults were included. Data was extracted from each study and tabulated. Outcomes were categorized into 3 groups: 'slope', 'survival', and 'asymptote' models. Wordclouds were drawn wherein the frequency of variables occurring in the reviewed models is indicated by their size and color. 69 covariates were identified in the final models of 35 studies. Effect sizes of covariates were not directly quantitatively comparable in view of the combination of differing variables and scale transformation methods across models. Wordclouds enabled the identification of qualitative and semi-quantitative covariate sets for each outcome category. Comparison across categories identified sex, baseline age, baseline log viral load, baseline CD4, ART initiation regimen and ART duration as a minimal consensus set. Most models were different with respect to covariates included, variable transformations and scales, model assumptions, modelling strategies and reporting methods, even for the same outcomes. To enable comparison across cohorts, statistical models would benefit from the application of more uniform modelling techniques. Historic efforts have produced results that are anecdotal to individual cohorts only. This study was able to define 'prior' knowledge in the Bayesian sense. Such information has value for prospective modelling efforts.

Falls, Cognitive Impairment, and Gait Performance: Results From the GOOD Initiative

PubMed Central

Allali, Gilles; Launay, Cyrille P.; Blumen, Helena M.; Callisaya, Michele L.; De Cock, Anne-Marie; Kressig, Reto W.; Srikanth, Velandai; Steinmetz, Jean-Paul; Verghese, Joe; Beauchet, Olivier

2017-01-01

Objectives Falls are highly prevalent in individuals with cognitive decline. The complex relationship between falls and cognitive decline (including both subtype and severity of dementia) and the influence of gait disorders have not been studied. This study aimed to examine the association between the subtype (Alzheimer disease [AD] versus non-AD) and the severity (from preclinical to moderate dementia) of cognitive impairment and falls, and to establish an association between falls and gait parameters during the course of dementia. Design Multicenter cross-sectional study. Setting “Gait, cOgnitiOn & Decline” (GOOD) initiative. Participants A total of 2496 older adults (76.6 ± 7.6 years; 55.0% women) were included in this study (1161 cognitively healthy individuals [CHI], 529 patients with mild cognitive impairment [MCI], 456 patients with mild dementia, and 350 with moderate dementia) from 7 countries. Measurements Falls history was collected retrospectively at baseline in each study. Gait speed and stride time variability were recorded at usual walking pace with the GAITRite system. Results The prevalence of individuals who fall was 50% in AD and 64% in non-AD; whereas it was 25% in CHIs. Only mild and moderate non-AD dementia were associated with an increased risk for falls in comparison with CHI. Higher stride time variability was associated with falls in older adults without dementia (CHI and each MCI subgroup) and mild non-AD dementia, whereas lower gait speed was associated with falls in all participant groups, except in mild AD dementia. When gait speed was adjusted for, higher stride time variability was associated with falls only in CHIs (odds ratio 1.14; P = .012), but not in MCI or in patients with dementia. Conclusions These findings suggest that non-AD, but not AD dementia, is associated with increased falls in comparison with CHIs. The association between gait parameters and falls also differs across cognitive status, suggesting different mechanisms leading to falls in older individuals with dementia in comparison with CHIs who fall. PMID:27914848

Stress and its effects on medical students: a cross-sectional study at a college of medicine in Saudi Arabia.

PubMed

Abdulghani, Hamza M; AlKanhal, Abdulaziz A; Mahmoud, Ebrahim S; Ponnamperuma, Gominda G; Alfaris, Eiad A

2011-10-01

Medical education is perceived as being stressful, and a high level of stress may have a negative effect on cognitive functioning and learning of students in a medical school. This cross-sectional study was conducted to determine the prevalence of stress among medical students and to observe an association between the levels of stress and their academic performance, including the sources of their stress. All the medical students from year one to year five levels from the College of Medicine, King Saud University, were enrolled in the study. The study was conducted using Kessler10 psychological distress (K10) inventory, which measures the level of stress according to none, mild, moderate, and severe categories. The prevalence of stress was measured and compared with the five study variables, such as gender, academic year, academic grades, regularity to course attendance, and perceived physical problems. The response rate among the study subjects was 87% (n=892). The total prevalence of stress was 63%, and the prevalence of severe stress was 25%. The prevalence of stress was higher (p<0.5) among females (75.7%) than among males (57%) (odds ratio=2.3, chi2=27.2, p<0.0001). The stress significantly decreased as the year of study increased, except for the final year. The study variables, including being female (p<0.0001), year of study (p<0.001), and presence of perceived physical problems (p<0.0001), were found as independent significant risk factors for the outcome variables of stress. Students' grade point average (academic score) or regularity to attend classes was not significantly associated with the stress level. The prevalence of stress was higher during the initial three years of study and among the female students. Physical problems are associated with high stress levels. Preventive mental health services, therefore, could be made an integral part of routine clinical services for medical students, especially in the initial academic years, to prevent such occurrence.

Replication of Simulated Prebiotic Amphiphilic Vesicles in a Finite Environment Exhibits Complex Behavior That Includes High Progeny Variability and Competition

PubMed Central

Armstrong, Don L.; Lancet, Doron

2018-01-01

Abstract We studied the simulated replication and growth of prebiotic vesicles composed of 140 phospholipids and cholesterol using our R-GARD (Real Graded Autocatalysis Replication Domain) formalism that utilizes currently extant lipids that have known rate constants of lipid-vesicle interactions from published experimental data. R-GARD normally modifies kinetic parameters of lipid-vesicle interactions based on vesicle composition and properties. Our original R-GARD model tracked the growth and division of one vesicle at a time in an environment with unlimited lipids at a constant concentration. We explore here a modified model where vesicles compete for a finite supply of lipids. We observed that vesicles exhibit complex behavior including initial fast unrestricted growth, followed by intervesicle competition for diminishing resources, then a second growth burst driven by better-adapted vesicles, and ending with a final steady state. Furthermore, in simulations without kinetic parameter modifications (“invariant kinetics”), the initial replication was an order of magnitude slower, and vesicles' composition variability at the final steady state was much lower. The complex kinetic behavior was not observed either in the previously published R-GARD simulations or in additional simulations presented here with only one lipid component. This demonstrates that both a finite environment (inducing selection) and multiple components (providing variation for selection to act upon) are crucial for portraying evolution-like behavior. Such properties can improve survival in a changing environment by increasing the ability of early protocellular entities to respond to rapid environmental fluctuations likely present during abiogenesis both on Earth and possibly on other planets. This in silico simulation predicts that a relatively simple in vitro chemical system containing only lipid molecules might exhibit properties that are relevant to prebiotic processes. Key Words: Phospholipid vesicles—Prebiotic compartments—Prebiotic vesicle competition—Prebiotic vesicle variability. Astrobiology 18, 419–430. PMID:29634319

Estimate of shock-Hugoniot adiabat of liquids from hydrodyamics

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

Bouton, E.; Vidal, P.

2007-12-12

Shock states are generally obtained from shock velocity (D) and material velocity (u) measurements. In this paper, we propose a hydrodynamical method for estimating the (D-u) relation of Nitromethane from easily measured properties of the initial state. The method is based upon the differentiation of the Rankine-Hugoniot jump relations with the initial temperature considered as a variable and under the constraint of a unique nondimensional shock-Hugoniot. We then obtain an ordinary differential equation for the shock velocity D in the variable u. Upon integration, this method predicts the shock Hugoniot of liquid Nitromethane with a 5% accuracy for initial temperaturesmore » ranging from 250 K to 360 K.« less

A Retrospective Analysis of Corticosteroid Utilization Before Initiation of Biologic DMARDs Among Patients with Rheumatoid Arthritis in the United States.

PubMed

Spivey, Christina A; Griffith, Jenny; Kaplan, Cameron; Postlethwaite, Arnold; Ganguli, Arijit; Wang, Junling

2018-06-01

Understanding the effects of corticosteroid utilization prior to initiation of biologic disease-modifying antirheumatic drugs (DMARDs) can inform decision-makers on the appropriate use of these medications. This study examined treatment patterns and associated burden of corticosteroid utilization before initiation of biologic DMARDs among rheumatoid arthritis (RA) patients. A retrospective analysis was conducted of adult RA patients in the US MarketScan Database (2011-2015). The following patterns of corticosteroid utilization were analyzed: whether corticosteroids were used; duration of use (short/long duration defined as < or ≥ 3 months); and dosage (low as < 2.5, medium as 2.5 to < 7.5 and high as ≥ 7.5 mg/day). Effects of corticosteroid use on time to biologic DMARD initiation were examined using Cox proportional hazards models. Likelihood and number of adverse events were examined using logistic and negative binomial regression models. Generalized linear models were used to examine healthcare costs. Independent variables in all models included patient demographics and health characteristics. A total of 25,542 patients were included (40.84% used corticosteroids). Lower hazard of biologic DMARD initiation was associated with corticosteroid use (hazard ratio = 0.89, 95% confidence interval = 0.83-0.96), long duration and lower dose. Corticosteroid users compared to non-users had higher incidence rates of various adverse events including cardiovascular events (P < 0.05). Higher likelihood of adverse events was associated with corticosteroid use and long duration of use, as was increased number of adverse events. Corticosteroid users had a greater annualized mean number of physician visits, hospitalizations, and emergency department (ED) visits than non-users in adjusted analysis. Corticosteroid users compared to non-users had higher mean costs for total healthcare, physician visits, hospitalizations, and ED visits. Among patients with RA, corticosteroid utilization is associated with delayed initiation of biologic DMARDS and higher burden of adverse events and healthcare utilization/costs before the initiation of biologic DMARDs. AbbVie Inc.

Carbon monoxide poisoning from waterpipe smoking: a retrospective cohort study.

PubMed

Eichhorn, Lars; Michaelis, Dirk; Kemmerer, Michael; Jüttner, Björn; Tetzlaff, Kay

2018-04-01

Waterpipe smoking may increasingly account for unintentional carbon monoxide poisoning, a serious health hazard with high morbidity and mortality. We aimed at identifying waterpipe smoking as a cause for carbon monoxide poisoning in a large critical care database of a specialty care referral center. This retrospective cohort study included patients with a history of exposure to waterpipe smoking and carbon monoxide blood gas levels >10% or presence of clinical symptoms compatible with CO poisoning admitted between January 2013 and December 2016. Patients' initial symptoms and carbon monoxide blood levels were retrieved from records and neurologic status was assessed before and after hyperbaric oxygen treatment. Sixty-one subjects with carbon monoxide poisoning were included [41 males, 20 females; mean age 23 (SD ± 6) years; range 13-45] with an initial mean carboxyhemoglobin of 26.93% (SD ± 9.72). Most common symptoms included syncope, dizziness, headache, and nausea; 75% had temporary syncope. Symptoms were not closely associated with blood COHb levels. CO poisoning after waterpipe smoking may present in young adults with a wide variability of symptoms from none to unconsciousness. Therefore diagnosis should be suspected even in the absence of symptoms.

Phenotypic Variability in Autosomal Dominant Familial Alzheimer Disease due to the S170F Mutation of Presenilin-1.

PubMed

Tiedt, Hannes O; Benjamin, Beate; Niedeggen, Michael; Lueschow, Andreas

2018-02-22

In rare cases, patients with Alzheimer disease (AD) present at an early age and with a family history suggestive of an autosomal dominant mode of inheritance. Mutations of the presenilin-1 (PSEN1) gene are the most common causes of dementia in these patients. Early-onset and particularly familial AD patients frequently present with variable non-amnestic cognitive symptoms such as visual, language or behavioural changes as well as non-cognitive, e.g. motor, symptoms. To investigate the phenotypic variability in carriers of the PSEN1 S170F mutation. We report a family with 4 patients carrying the S170F mutation of whom 2 underwent detailed clinical examinations. We discuss our current findings in the context of previously reported S170F cases. The clinical phenotype was consistent regarding initial memory impairment and early onset in the late twenties found in all S170F patients. There were frequent non-amnestic cognitive changes and, at early stages of the disease, indications of a more pronounced disturbance of visuospatial abilities as compared to face and object recognition. Non-cognitive symptoms most often included myoclonus and cerebellar ataxia. A review of the available case reports indicates some phenotypic variability associated with the S170F mutation including different constellations of symptoms such as parkinsonism and delusions. The variable clinical findings associated with the S170F mutation highlight the relevance of atypical phenotypes in the context of research and under a clinical perspective. CSF sampling and detection of Aβ species may be essential to indicate AD pathology in unclear cases presenting with cognitive and motor symptoms at a younger age. © 2018 S. Karger AG, Basel.

Linking bovine tuberculosis on cattle farms to white-tailed deer and environmental variables using Bayesian hierarchical analysis

USGS Publications Warehouse

Walter, W. David; Smith, Rick; Vanderklok, Mike; VerCauterren, Kurt C.

2014-01-01

Bovine tuberculosis is a bacterial disease caused by Mycobacterium bovis in livestock and wildlife with hosts that include Eurasian badgers (Meles meles), brushtail possum (Trichosurus vulpecula), and white-tailed deer (Odocoileus virginianus). Risk-assessment efforts in Michigan have been initiated on farms to minimize interactions of cattle with wildlife hosts but research onM. bovis on cattle farms has not investigated the spatial context of disease epidemiology. To incorporate spatially explicit data, initial likelihood of infection probabilities for cattle farms tested for M. bovis, prevalence of M. bovis in white-tailed deer, deer density, and environmental variables for each farm were modeled in a Bayesian hierarchical framework. We used geo-referenced locations of 762 cattle farms that have been tested for M. bovis, white-tailed deer prevalence, and several environmental variables that may lead to long-term survival and viability of M. bovis on farms and surrounding habitats (i.e., soil type, habitat type). Bayesian hierarchical analyses identified deer prevalence and proportion of sandy soil within our sampling grid as the most supported model. Analysis of cattle farms tested for M. bovisidentified that for every 1% increase in sandy soil resulted in an increase in odds of infection by 4%. Our analysis revealed that the influence of prevalence of M. bovis in white-tailed deer was still a concern even after considerable efforts to prevent cattle interactions with white-tailed deer through on-farm mitigation and reduction in the deer population. Cattle farms test positive for M. bovis annually in our study area suggesting that the potential for an environmental source either on farms or in the surrounding landscape may contributing to new or re-infections with M. bovis. Our research provides an initial assessment of potential environmental factors that could be incorporated into additional modeling efforts as more knowledge of deer herd factors and cattle farm prevalence is documented.

Angiographic assessment of initial balloon angioplasty results.

PubMed

Gardiner, Geoffrey A; Sullivan, Kevin L; Halpern, Ethan J; Parker, Laurence; Beck, Margaret; Bonn, Joseph; Levin, David C

2004-10-01

To determine the influence of three factors involved in the angiographic assessment of balloon angioplasty-interobserver variability, operator bias, and the definition used to determine success-on the primary (technical) results of angioplasty in the peripheral arteries. Percent stenosis in 107 lesions in lower-extremity arteries was graded by three independent, experienced vascular radiologists ("observers") before and after balloon angioplasty and their estimates were compared with the initial interpretations reported by the physician performing the procedure ("operator") and an automated quantitative computer analysis. Observer variability was measured with use of intraclass correlation coefficients and SD. Differences among the operator, observers, and the computer were analyzed with use of the Wilcoxon signed-rank test and analysis of variance. For each evaluator, the results in this series of lesions were interpreted with three different definitions of success. Estimation of residual stenosis varied by an average range of 22.76% with an average SD of 8.99. The intraclass correlation coefficients averaged 0.59 for residual stenosis after angioplasty for the three observers but decreased to 0.36 when the operator was included as the fourth evaluator. There was good to very good agreement among the three independent observers and the computer, but poor correlation with the operator (P

Smoker Characteristics and Smoking-Cessation Milestones

PubMed Central

Japuntich, Sandra J.; Leventhal, Adam M.; Piper, Megan E.; Bolt, Daniel M.; Roberts, Linda J.; Fiore, Michael C.; Baker, Timothy B.

2011-01-01

Background Contextual variables often predict long-term abstinence, but little is known about how these variables exert their effects. These variables could influence abstinence by affecting the ability to quit at all, or by altering risk of lapsing, or progressing from a lapse to relapse. Purpose To examine the effect of common predictors of smoking-cessation failure on smoking-cessation processes. Methods The current study (N = 1504, 58% female, 84% Caucasian; recruited from January 2005 to June 2007; data analyzed in 2009) uses the approach advocated by Shiffman et al., (2006), which measures cessation outcomes on three different cessation milestones (achieving initial abstinence, lapse risk, and the lapse-relapse transition) to examine relationships of smoker characteristics (dependence, contextual and demographic factors) with smoking-cessation process. Results High nicotine dependence strongly predicted all milestones: not achieving initial abstinence, and a higher risk of both lapse and transitioning from lapse to complete relapse. Numerous contextual and demographic variables were associated with higher initial cessation rates and/or decreased lapse risk at 6 months post-quit (e.g., ethnicity, gender, marital status, education, smoking in the workplace, number of smokers in the social network, and number of supportive others). However, aside from nicotine dependence, only gender significantly predicted the risk of transition from lapse to relapse. Conclusions These findings demonstrate that: (1) higher nicotine dependence predicted worse outcomes across every cessation milestone; (2) demographic and contextual variables are generally associated with initial abstinence rates and lapse risk and not the lapse-relapse transition. These results identify groups who are at risk for failure at specific stages of the smoking-cessation process, and this may have implications for treatment. PMID:21335259

Validation of an ocean shelf model for the prediction of mixed-layer properties in the Mediterranean Sea west of Sardinia

NASA Astrophysics Data System (ADS)

Onken, Reiner

2017-04-01

The Regional Ocean Modeling System (ROMS) has been employed to explore the sensitivity of the forecast skill of mixed-layer properties to initial conditions, boundary conditions, and vertical mixing parameterisations. The initial and lateral boundary conditions were provided by the Mediterranean Forecasting System (MFS) or by the MERCATOR global ocean circulation model via one-way nesting; the initial conditions were additionally updated through the assimilation of observations. Nowcasts and forecasts from the weather forecast models COSMO-ME and COSMO-IT, partly melded with observations, served as surface boundary conditions. The vertical mixing was parameterised by the GLS (generic length scale) scheme Umlauf and Burchard (2003) in four different set-ups. All ROMS forecasts were validated against the observations which were taken during the REP14-MED survey to the west of Sardinia. Nesting ROMS in MERCATOR and updating the initial conditions through data assimilation provided the best agreement of the predicted mixed-layer properties with the time series from a moored thermistor chain. Further improvement was obtained by the usage of COSMO-ME atmospheric forcing, which was melded with real observations, and by the application of the k-ω vertical mixing scheme with increased vertical eddy diffusivity. The predicted temporal variability of the mixed-layer temperature was reasonably well correlated with the observed variability, while the modelled variability of the mixed-layer depth exhibited only agreement with the observations near the diurnal frequency peak. For the forecasted horizontal variability, reasonable agreement was found with observations from a ScanFish section, but only for the mesoscale wave number band; the observed sub-mesoscale variability was not reproduced by ROMS.

Need for Initiatives to Promote Procedural Understanding in Physics among School Teachers

NASA Astrophysics Data System (ADS)

Khaparde, Rajesh B.

2010-07-01

It is believed that there are three essential abilities which a student develops through a set of introductory physics laboratory courses. These abilities include 1) conceptual understanding, 2) experimental skills, and 3) procedural understanding. While the first two are well accepted, the third one is often implicit and goes behind the planning and execution of experimental physics. Procedural understanding has been described by a number of researchers including R. Gott and S. Duggan [1], and R. Roberts [2]. The author in his work [3] has adopted the approach of these researchers and extended it to physics laboratory training at the university level. Procedural understanding is the understanding of a set of ideas or concepts related to the `knowing how' of science and needed to put science into practice. It is the understanding of `concepts of evidence' like variable identification, sample size, variable types, relative scale, range, interval, choice of instruments, repeatability, graph type, etc. It is the thinking behind the doing and is a kind of cognitive understanding in its own right. It has been observed that while school (Grade 1-12) teachers are reasonably prepared to help students with respect to the development of conceptual understanding and experimental skills, a few are aware of the contents, methods and strategies related to the development of procedural understanding. It is felt that school teachers can play a very important role in helping students to develop procedural understanding at an early stage of their education and before students enter university courses. A need was felt to initiate and promote well-planned teacher improvement programmes at various levels of school education, with an objective to develop procedural understanding and understand the strategies of teaching suitable for various regions and learning environments. The author has initiated one such programme in India and will present details of a workshop organized at Mumbai, India.

Programming and execution of movement in Parkinson's disease.

PubMed

Sheridan, M R; Flowers, K A; Hurrell, J

1987-10-01

Programming and execution of arm movements in Parkinson's disease were investigated in choice and simple reaction time (RT) situations in which subjects made aimed movements at a target. A no-aiming condition was also studied. Reaction time was fractionated using surface EMG recording into premotor (central) and motor (peripheral) components. Premotor RT was found to be greater for parkinsonian patients than normal age-matched controls in the simple RT condition, but not in the choice condition. This effect did not depend on the parameters of the impending movement. Thus, paradoxically, parkinsonian patients were not inherently slower at initiating aiming movements from the starting position, but seemed unable to use advance information concerning motor task demands to speed up movement initiation. For both groups, low velocity movements took longer to initiate than high velocity ones. In the no-aiming condition parkinsonian RTs were markedly shorter than when aiming, but were still significantly longer than control RTs. Motor RT was constant across all conditions and was not different for patient and control subjects. In all conditions, parkinsonian movements were around 37% slower than control movements, and their movement times were more variable, the differences showing up early on in the movement, that is, during the initial ballistic phase. The within-subject variability of movement endpoints was also greater in patients. The motor dysfunction displayed in Parkinson's disease involves a number of components: (1) a basic central problem with simply initiating movements, even when minimal programming is required (no-aiming condition); (2) difficulty in maintaining computed forces for motor programs over time (simple RT condition); (3) a basic slowness of movement (bradykinesia) in all conditions; and (4) increased variability of movement in both time and space, presumably caused by inherent variability in force production.

Rotorcraft handling-qualities design criteria development

NASA Technical Reports Server (NTRS)

Aiken, Edwin W.; Lebacqz, J. Victor; Chen, Robert T. N.; Key, David L.

1988-01-01

Joint NASA/Army efforts at the Ames Research Center to develop rotorcraft handling-qualities design criteria began in earnest in 1975. Notable results were the UH-1H VSTOLAND variable stability helicopter, the VFA-2 camera-and-terrain-board simulator visual system, and the generic helicopter real-time mathematical model, ARMCOP. An initial series of handling-qualities studies was conducted to assess the effects of rotor design parameters, interaxis coupling, and various levels of stability and control augmentation. The ability to conduct in-flight handling-qualities research was enhanced by the development of the NASA/Army CH-47 variable-stability helicopter. Research programs conducted using this vehicle include vertical-response investigations, hover augmentation systems, and the effects of control-force characteristics. The handling-qualities data base was judged to be sufficient to allow an update of the military helicopter handling-qualities specification, MIL-H-8501. These efforts, including not only the in-house experimental work but also contracted research and collaborative programs performed under the auspices of various international agreements. The report concludes by reviewing the topics that are currently most in need of work, and the plans for addressing these topics.

Apparatus for and method of testing an electrical ground fault circuit interrupt device

DOEpatents

Andrews, L.B.

1998-08-18

An apparatus for testing a ground fault circuit interrupt device includes a processor, an input device connected to the processor for receiving input from an operator, a storage media connected to the processor for storing test data, an output device connected to the processor for outputting information corresponding to the test data to the operator, and a calibrated variable load circuit connected between the processor and the ground fault circuit interrupt device. The ground fault circuit interrupt device is configured to trip a corresponding circuit breaker. The processor is configured to receive signals from the calibrated variable load circuit and to process the signals to determine a trip threshold current and/or a trip time. A method of testing the ground fault circuit interrupt device includes a first step of providing an identification for the ground fault circuit interrupt device. Test data is then recorded in accordance with the identification. By comparing test data from an initial test with test data from a subsequent test, a trend of performance for the ground fault circuit interrupt device is determined. 17 figs.

Apparatus for and method of testing an electrical ground fault circuit interrupt device

DOEpatents

Andrews, Lowell B.

1998-01-01

An apparatus for testing a ground fault circuit interrupt device includes a processor, an input device connected to the processor for receiving input from an operator, a storage media connected to the processor for storing test data, an output device connected to the processor for outputting information corresponding to the test data to the operator, and a calibrated variable load circuit connected between the processor and the ground fault circuit interrupt device. The ground fault circuit interrupt device is configured to trip a corresponding circuit breaker. The processor is configured to receive signals from the calibrated variable load circuit and to process the signals to determine a trip threshold current and/or a trip time. A method of testing the ground fault circuit interrupt device includes a first step of providing an identification for the ground fault circuit interrupt device. Test data is then recorded in accordance with the identification. By comparing test data from an initial test with test data from a subsequent test, a trend of performance for the ground fault circuit interrupt device is determined.

A global multiproxy database for temperature reconstructions of the Common Era.

PubMed

2017-07-11

Reproducible climate reconstructions of the Common Era (1 CE to present) are key to placing industrial-era warming into the context of natural climatic variability. Here we present a community-sourced database of temperature-sensitive proxy records from the PAGES2k initiative. The database gathers 692 records from 648 locations, including all continental regions and major ocean basins. The records are from trees, ice, sediment, corals, speleothems, documentary evidence, and other archives. They range in length from 50 to 2000 years, with a median of 547 years, while temporal resolution ranges from biweekly to centennial. Nearly half of the proxy time series are significantly correlated with HadCRUT4.2 surface temperature over the period 1850-2014. Global temperature composites show a remarkable degree of coherence between high- and low-resolution archives, with broadly similar patterns across archive types, terrestrial versus marine locations, and screening criteria. The database is suited to investigations of global and regional temperature variability over the Common Era, and is shared in the Linked Paleo Data (LiPD) format, including serializations in Matlab, R and Python.

Use of a deuterated internal standard with pyrolysis-GC/MS dimeric marker analysis to quantify tire tread particles in the environment.

PubMed

Unice, Kenneth M; Kreider, Marisa L; Panko, Julie M

2012-11-08

Pyrolysis(pyr)-GC/MS analysis of characteristic thermal decomposition fragments has been previously used for qualitative fingerprinting of organic sources in environmental samples. A quantitative pyr-GC/MS method based on characteristic tire polymer pyrolysis products was developed for tread particle quantification in environmental matrices including soil, sediment, and air. The feasibility of quantitative pyr-GC/MS analysis of tread was confirmed in a method evaluation study using artificial soil spiked with known amounts of cryogenically generated tread. Tread concentration determined by blinded analyses was highly correlated (r2 ≥ 0.88) with the known tread spike concentration. Two critical refinements to the initial pyrolysis protocol were identified including use of an internal standard and quantification by the dimeric markers vinylcyclohexene and dipentene, which have good specificity for rubber polymer with no other appreciable environmental sources. A novel use of deuterated internal standards of similar polymeric structure was developed to correct the variable analyte recovery caused by sample size, matrix effects, and ion source variability. The resultant quantitative pyr-GC/MS protocol is reliable and transferable between laboratories.

A global multiproxy database for temperature reconstructions of the Common Era

USGS Publications Warehouse

Emile-Geay, Julian; McKay, Nicholas P.; Kaufman, Darrell S.; von Gunten, Lucien; Wang, Jianghao; Anchukaitis, Kevin J.; Abram, Nerilie J.; Addison, Jason A.; Curran, Mark A.J.; Evans, Michael N.; Henley, Benjamin J.; Hao, Zhixin; Martrat, Belen; McGregor, Helen V.; Neukom, Raphael; Pederson, Gregory T.; Stenni, Barbara; Thirumalai, Kaustubh; Werner, Johannes P.; Xu, Chenxi; Divine, Dmitry V.; Dixon, Bronwyn C.; Gergis, Joelle; Mundo, Ignacio A.; Nakatsuka, T.; Phipps, Steven J.; Routson, Cody C.; Steig, Eric J.; Tierney, Jessica E.; Tyler, Jonathan J.; Allen, Kathryn J.; Bertler, Nancy A. N.; Bjorklund, Jesper; Chase, Brian M.; Chen, Min-Te; Cook, Ed; de Jong, Rixt; DeLong, Kristine L.; Dixon, Daniel A.; Ekaykin, Alexey A.; Ersek, Vasile; Filipsson, Helena L.; Francus, Pierre; Freund, Mandy B.; Frezzotti, M.; Gaire, Narayan P.; Gajewski, Konrad; Ge, Quansheng; Goosse, Hugues; Gornostaeva, Anastasia; Grosjean, Martin; Horiuchi, Kazuho; Hormes, Anne; Husum, Katrine; Isaksson, Elisabeth; Kandasamy, Selvaraj; Kawamura, Kenji; Koc, Nalan; Leduc, Guillaume; Linderholm, Hans W.; Lorrey, Andrew M.; Mikhalenko, Vladimir; Mortyn, P. Graham; Motoyama, Hideaki; Moy, Andrew D.; Mulvaney, Robert; Munz, Philipp M.; Nash, David J.; Oerter, Hans; Opel, Thomas; Orsi, Anais J.; Ovchinnikov, Dmitriy V.; Porter, Trevor J.; Roop, Heidi; Saenger, Casey; Sano, Masaki; Sauchyn, David; Saunders, K.M.; Seidenkrantz, Marit-Solveig; Severi, Mirko; Shao, X.; Sicre, Marie-Alexandrine; Sigl, Michael; Sinclair, Kate; St. George, Scott; St. Jacques, Jeannine-Marie; Thamban, Meloth; Thapa, Udya Kuwar; Thomas, E.; Turney, Chris; Uemura, Ryu; Viau, A.E.; Vladimirova, Diana O.; Wahl, Eugene; White, James W. C.; Yu, Z.; Zinke, Jens

2017-01-01

Reproducible climate reconstructions of the Common Era (1 CE to present) are key to placing industrial-era warming into the context of natural climatic variability. Here we present a community-sourced database of temperature-sensitive proxy records from the PAGES2k initiative. The database gathers 692 records from 648 locations, including all continental regions and major ocean basins. The records are from trees, ice, sediment, corals, speleothems, documentary evidence, and other archives. They range in length from 50 to 2000 years, with a median of 547 years, while temporal resolution ranges from biweekly to centennial. Nearly half of the proxy time series are significantly correlated with HadCRUT4.2 surface temperature over the period 1850–2014. Global temperature composites show a remarkable degree of coherence between high- and low-resolution archives, with broadly similar patterns across archive types, terrestrial versus marine locations, and screening criteria. The database is suited to investigations of global and regional temperature variability over the Common Era, and is shared in the Linked Paleo Data (LiPD) format, including serializations in Matlab, R and Python.

The MedCLIVAR Network

NASA Astrophysics Data System (ADS)

Lionello, Piero; Medclivar sg, The

2013-04-01

The MedCLIVAR initiative was first proposed at the 2003 European Geosciences Union assembly in Nice, France. In 2005, it was endorsed by the International Climate Variability and Predictability (CLIVAR) office. Subsequently, the MedCLIVAR Research Network Project was formally approved by the European Science Foundation and launched in May 2006 with the support of funding agencies from 12 countries. Since then, MedCLIVAR has served as a scientific network to promote interaction among different scientific disciplines and to develop a multidisciplinary vision of the evolution of the Mediterranean climate through studies that integrate atmospheric, marine, and terrestrial climate components at time scales ranging from paleoreconstructions to future climate scenarios. Presently, the network continues dealing with scientific issues including past climate variability; connections between the Mediterranean and global climate; the Mediterranean Sea circulation and sea level; feedbacks on the global climate system; and regional responses to greenhouse gas, air pollution, and aerosols. Its present activities include the publication of a newsletter, the organization of the next MedCLIVAR conference in 2014 and the publication of a special issue of Regional Environmental Change devoted to the climate of the Mediterranean region.

A global multiproxy database for temperature reconstructions of the Common Era

PubMed Central

Emile-Geay, Julien; McKay, Nicholas P.; Kaufman, Darrell S.; von Gunten, Lucien; Wang, Jianghao; Anchukaitis, Kevin J.; Abram, Nerilie J.; Addison, Jason A.; Curran, Mark A.J.; Evans, Michael N.; Henley, Benjamin J.; Hao, Zhixin; Martrat, Belen; McGregor, Helen V.; Neukom, Raphael; Pederson, Gregory T.; Stenni, Barbara; Thirumalai, Kaustubh; Werner, Johannes P.; Xu, Chenxi; Divine, Dmitry V.; Dixon, Bronwyn C.; Gergis, Joelle; Mundo, Ignacio A.; Nakatsuka, Takeshi; Phipps, Steven J.; Routson, Cody C.; Steig, Eric J.; Tierney, Jessica E.; Tyler, Jonathan J.; Allen, Kathryn J.; Bertler, Nancy A.N.; Björklund, Jesper; Chase, Brian M.; Chen, Min-Te; Cook, Ed; de Jong, Rixt; DeLong, Kristine L.; Dixon, Daniel A.; Ekaykin, Alexey A.; Ersek, Vasile; Filipsson, Helena L.; Francus, Pierre; Freund, Mandy B.; Frezzotti, Massimo; Gaire, Narayan P.; Gajewski, Konrad; Ge, Quansheng; Goosse, Hugues; Gornostaeva, Anastasia; Grosjean, Martin; Horiuchi, Kazuho; Hormes, Anne; Husum, Katrine; Isaksson, Elisabeth; Kandasamy, Selvaraj; Kawamura, Kenji; Kilbourne, K. Halimeda; Koç, Nalan; Leduc, Guillaume; Linderholm, Hans W.; Lorrey, Andrew M.; Mikhalenko, Vladimir; Mortyn, P. Graham; Motoyama, Hideaki; Moy, Andrew D.; Mulvaney, Robert; Munz, Philipp M.; Nash, David J.; Oerter, Hans; Opel, Thomas; Orsi, Anais J.; Ovchinnikov, Dmitriy V.; Porter, Trevor J.; Roop, Heidi A.; Saenger, Casey; Sano, Masaki; Sauchyn, David; Saunders, Krystyna M.; Seidenkrantz, Marit-Solveig; Severi, Mirko; Shao, Xuemei; Sicre, Marie-Alexandrine; Sigl, Michael; Sinclair, Kate; St. George, Scott; St. Jacques, Jeannine-Marie; Thamban, Meloth; Kuwar Thapa, Udya; Thomas, Elizabeth R.; Turney, Chris; Uemura, Ryu; Viau, Andre E.; Vladimirova, Diana O.; Wahl, Eugene R.; White, James W.C.; Yu, Zicheng; Zinke, Jens

2017-01-01

Reproducible climate reconstructions of the Common Era (1 CE to present) are key to placing industrial-era warming into the context of natural climatic variability. Here we present a community-sourced database of temperature-sensitive proxy records from the PAGES2k initiative. The database gathers 692 records from 648 locations, including all continental regions and major ocean basins. The records are from trees, ice, sediment, corals, speleothems, documentary evidence, and other archives. They range in length from 50 to 2000 years, with a median of 547 years, while temporal resolution ranges from biweekly to centennial. Nearly half of the proxy time series are significantly correlated with HadCRUT4.2 surface temperature over the period 1850–2014. Global temperature composites show a remarkable degree of coherence between high- and low-resolution archives, with broadly similar patterns across archive types, terrestrial versus marine locations, and screening criteria. The database is suited to investigations of global and regional temperature variability over the Common Era, and is shared in the Linked Paleo Data (LiPD) format, including serializations in Matlab, R and Python. PMID:28696409

Cognitive inconsistency in bipolar patients is determined by increased intra-individual variability in initial phase of task performance.

PubMed

Krukow, Paweł; Szaniawska, Ola; Harciarek, Michał; Plechawska-Wójcik, Małgorzata; Jonak, Kamil

2017-03-01

Bipolar patients show high intra-individual variability during cognitive processing. However, it is not known whether there are a specific fluctuations of variability contributing to the overall high cognitive inconsistency. The objective was to compare dynamic profiles of patients and healthy controls to identify hypothetical differences and their associations with overall variability and processing speed. Changes of reaction times iSD during processing speed test performance over time was measured by dividing the iSD for whole task into four consecutive parts. Motor speed and cognitive effort were controlled. Patients with BD exhibited significantly lower results regarding processing speed and higher intra-individual variability comparing with HC. The profile of intra-individual variability changes over time of performance was significantly different in BD versus HC groups: F(3, 207)=8.60, p<0.0001, η p 2 =0.11. iSD of BD patients in the initial phase of performance was three times higher than in the last. There was no significant differences between four intervals in HC group. Inter-group difference in the initial part of the profiles was significant also after controlling for several cognitive and clinical variables. Applied computer version of Cognitive Speed Test was relatively new and, thus, replication studies are needed. Effect seen in the present study is driven mainly by the BD type I. Patients with BD exhibits problems with setting a stimulus-response association in starting phase of cognitive processing. This deficit may negatively interfere with the other cognitive functions, decreasing level of psychosocial functioning, therefore should be explored in future studies. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of initial total solids concentration on volatile fatty acid production from food waste during anaerobic acidification.

PubMed

Wang, Quan; Jiang, Jianguo; Zhang, Yujing; Li, Kaimin

2015-01-01

The effect of initial total solids (TS) concentration on volatile fatty acid (VFAs) production from food waste under mesophilic conditions (35 °C) was determined. VFAs concentration and composition, biogas production, soluble chemical oxygen demand concentration, TS and volatile solids (VS) reduction, and ammonia nitrogen [Formula: see text] release were investigated. The VFAs concentrations were 26.10, 39.68, 59.58, and 62.64 g COD/L at TS contents of 40, 70, 100, and 130 g/L, respectively. While the VFAs' yields ranged from 0.467 to 0.799 g COD/g VSfed, decreased as initial TS increased. The percentage of propionate was not affected by TS concentration, accounting for 30.19-34.86% of the total VFAs, while a higher percentage of butyrate and lower percentage of acetate was achieved at a higher TS concentration. Biogas included mainly hydrogen and carbon dioxide and the maximum hydrogen yield of 148.9 ml/g VSfed was obtained at 130 g TS/L. [Formula: see text] concentration, TS and VS reductions increased as initial TS increased. Considering the above variables, we conclude that initial TS of 100 g/L shall be the most appropriate to VFAs production.

Breast-feeding initiation in low-income women: Role of attitudes, support, and perceived control.

PubMed

Khoury, Amal J; Moazzem, S Wakerul; Jarjoura, Chad M; Carothers, Cathy; Hinton, Agnes

2005-01-01

Despite the documented health and emotional benefits of breast-feeding to women and children, breast-feeding rates are low among subgroups of women. In this study, we examine factors associated with breast-feeding initiation in low-income women, including Theory of Planned Behavior measures of attitude, support, and perceived control, as well as sociodemographic characteristics. A mail survey, with telephone follow-up, of 733 postpartum Medicaid beneficiaries in Mississippi was conducted in 2000. The breast-feeding initiation rate in this population was 38%. Women who were older, white, non-Hispanic, college-educated, married, not certified for the Supplemental Nutrition Program for Women, Infants, and Children, and not working full-time were more likely to breast-feed than formula-feed at hospital discharge. Attitudes regarding benefits and barriers to breast-feeding, as well as health care system and social support, were associated with breast-feeding initiation at the multivariate level. Adding the health care system support variables to the regression model, and specifically support from lactation specialists and hospital nurses, explained the association between breast-feeding initiation and women's perceived control over the time and social constraints barriers to breast-feeding. The findings support the need for health care system interventions, family interventions, and public health education campaigns to promote breast-feeding in low-income women.

The Association between Quality Improvement Initiatives in Dementia Care and Supportive Psychosocial Work Environments in Nursing Homes.

PubMed

Nakanishi, Miharu; Tei-Tominaga, Maki

2018-05-08

Background : Quality improvement initiatives can help nursing homes strengthen psychosocial work environments. The aim of the present study was to examine the association between supportive psychosocial work environment, and professional and organizational characteristics regarding quality improvement initiatives in dementia care. Methods : A paper questionnaire survey was administered to a convenience sample of 365 professional caregivers in 12 special nursing homes in Japan. Psychosocial work environment was assessed using the Social Capital and Ethical Climate at the Workplace Scale to calculate a score of social capital in the workplace, ethical leadership, and exclusive workplace climate. Variables for quality improvement initiatives included type of home (unit-type or traditional), presence of additional benefit for dementia care, and professionalism in dementia care among caregivers evaluated using the Japanese version of the Sense of Competence in Dementia Care Staff Scale. Results : Elevated professionalism and unit-type home were significantly associated with high social capital, strong ethical leadership, and low exclusive workplace climate. The presence of dementia care benefit was not associated with any subscale of psychosocial work environment. Conclusions : Quality improvement initiatives to foster supportive psychosocial work environment should enhance professionalism in dementia care with unit-based team building of professional caregivers in special nursing homes.

International spinal cord injury endocrine and metabolic extended data set.

PubMed

Bauman, W A; Wecht, J M; Biering-Sørensen, F

2017-05-01

The objective of this study was to develop the International Spinal Cord Injury (SCI) Endocrine and Metabolic Extended Data Set (ISCIEMEDS) within the framework of the International SCI Data Sets that would facilitate consistent collection and reporting of endocrine and metabolic findings in the SCI population. This study was conducted in an international setting. The ISCIEMEDS was developed by a working group. The initial ISCIEMEDS was revised based on suggestions from members of the International SCI Data Sets Committee, the International Spinal Cord Society (ISCoS) Executive and Scientific Committees, American Spinal Injury Association (ASIA) Board, other interested organizations, societies and individual reviewers. The data set was posted for two months on ISCoS and ASIA websites for comments. Variable names were standardized, and a suggested database structure for the ISCIEMEDS was provided by the Common Data Elements (CDEs) project at the National Institute on Neurological Disorders and Stroke (NINDS) of the US National Institute of Health (NIH), and are available at https://commondataelements.ninds.nih.gov/SCI.aspx#tab=Data_Standards. The final ISCIEMEDS contains questions on the endocrine and metabolic conditions related to SCI. Because the information may be collected at any time, the date of data collection is important to determine the time after SCI. ISCIEMEDS includes information on carbohydrate metabolism (6 variables), calcium and bone metabolism (12 variables), thyroid function (9 variables), adrenal function (2 variables), gonadal function (7 variables), pituitary function (6 variables), sympathetic nervous system function (1 variable) and renin-aldosterone axis function (2 variables). The complete instructions for data collection and the data sheet itself are freely available on the website of ISCoS (http://www.iscos.org.uk/international-sci-data-sets).

Extreme infrared variables from UKIDSS - II. An end-of-survey catalogue of eruptive YSOs and unusual stars

NASA Astrophysics Data System (ADS)

Lucas, P. W.; Smith, L. C.; Contreras Peña, C.; Froebrich, D.; Drew, J. E.; Kumar, M. S. N.; Borissova, J.; Minniti, D.; Kurtev, R.; Monguió, M.

2017-12-01

We present a catalogue of 618 high-amplitude infrared variable stars (1 < ΔK < 5 mag) detected by the two widely separated epochs of 2.2 μm data in the UKIDSS Galactic plane survey, from searches covering ∼1470 deg2. Most were discovered by a search of all fields at 30 < l < 230°. Sources include new dusty Mira variables, three new cataclysmic variable candidates, a blazar and a peculiar source that may be an interacting binary system. However, ∼60 per cent are young stellar obbjects (YSOs), based on spatial association with star-forming regions at distances ranging from 300 pc to over 10 kpc. This confirms our initial result in Contreras Peña et al. (Paper I) that YSOs dominate the high-amplitude infrared variable sky in the Galactic disc. It is also supported by recently published VISTA Variables in the Via Lactea (VVV) results at 295 < l < 350°. The spectral energy distributions of the YSOs indicate class I or flat-spectrum systems in most cases, as in the VVV sample. A large number of variable YSOs are associated with the Cygnus X complex and other groups are associated with the North America/Pelican nebula, the Gemini OB1 molecular cloud, the Rosette complex, the Cone nebula, the W51 star-forming region and the S86 and S236 H II regions. Most of the YSO variability is likely due to variable/episodic accretion on time-scales of years, albeit usually less extreme than classical FUors and EXors. Luminosities at the 2010 Wide-field Infrared Survey Explorer epoch range from ∼0.1 to 103 L⊙ but only rarely exceed 102.5 L⊙.

Correlates and predictors of colorectal cancer screening among male automotive workers.

PubMed

McQueen, Amy; Vernon, Sally W; Myers, Ronald E; Watts, Beatty G; Lee, Eun Sul; Tilley, Barbara C

2007-03-01

Most studies examining factors associated with colorectal cancer (CRC) screening (CRCS) are cross-sectional and thus temporal relationships cannot be determined. Furthermore, less attention has been paid to psychosocial predictors of CRCS. We examined both cross-sectional correlates of prior CRCS and predictors of prospective CRCS initiation and maintenance during The Next Step Trial, a 2-year worksite behavioral intervention to promote regular CRCS and dietary change. The sample included 2,693 White male automotive workers at increased occupational risk for, but no history of, CRC who completed a baseline survey. Stratified analyses were conducted for three dependent variables (prior CRCS, CRCS initiation, and CRCS maintenance). We also assessed prior CRCS as a moderator in prospective analyses. Multivariable logistic regression analyses with generalized linear mixed models were used to adjust for cluster sampling. Except for education, cross-sectional correlates of prior CRCS including older age, family history of CRC or polyps, personal history of polyps, self-efficacy, family support, and intention were also significant prospective predictors of increased CRCS during the trial. Despite differences in the patterns of association for CRCS initiation and maintenance in stratified analyses, the only associations with prospective CRCS that were significantly moderated by prior CRCS were family history and CRCS availability. Correlates of prior CRCS that also were prospective predictors of CRCS may be suitable targets for intervention. Additionally, intervention messages addressing psychosocial constructs may be relevant for both CRCS initiation and maintenance. However, studies with more diverse samples are needed to replicate the results reported here.

Identification of Arbitrary Zonation in Groundwater Parameters using the Level Set Method and a Parallel Genetic Algorithm

NASA Astrophysics Data System (ADS)

Lei, H.; Lu, Z.; Vesselinov, V. V.; Ye, M.

2017-12-01

Simultaneous identification of both the zonation structure of aquifer heterogeneity and the hydrogeological parameters associated with these zones is challenging, especially for complex subsurface heterogeneity fields. In this study, a new approach, based on the combination of the level set method and a parallel genetic algorithm is proposed. Starting with an initial guess for the zonation field (including both zonation structure and the hydraulic properties of each zone), the level set method ensures that material interfaces are evolved through the inverse process such that the total residual between the simulated and observed state variables (hydraulic head) always decreases, which means that the inversion result depends on the initial guess field and the minimization process might fail if it encounters a local minimum. To find the global minimum, the genetic algorithm (GA) is utilized to explore the parameters that define initial guess fields, and the minimal total residual corresponding to each initial guess field is considered as the fitness function value in the GA. Due to the expensive evaluation of the fitness function, a parallel GA is adapted in combination with a simulated annealing algorithm. The new approach has been applied to several synthetic cases in both steady-state and transient flow fields, including a case with real flow conditions at the chromium contaminant site at the Los Alamos National Laboratory. The results show that this approach is capable of identifying the arbitrary zonation structures of aquifer heterogeneity and the hydrogeological parameters associated with these zones effectively.

QUALITY CONTROL - VARIABILITY IN PROTOCOLS

EPA Science Inventory

The EPA Risk Reduction Engineering Laboratory’s Quality Assurance Office, which published the popular pocket guide Preparing Perfect Project Plans, is now introducing another quality assurance reference aid. The document Variability in Protocols (VIP) was initially designed as a ...

Community demographics and the propensity to report animal cruelty.

PubMed

Taylor, Nicola; Signal, Tania D

2006-01-01

The last decade has seen an increased awareness concerning links between violence to nonhuman animals and violence to humans. This has resulted in a number of cross-reporting initiatives between family service providers and animal welfare organizations. The success of these initiatives rests on individuals being willing to report such violence. Thus, there is a need to determine which variables influence an individual's willingness to report deliberate animal cruelty and abuse. The aim of this study was to examine demographic and attitudinal variables to ascertain their impact on propensity to report deliberate animal harm. A telephone questionnaire resulted in 1,208 valid responses from members of the general community. Results showed a number of variables that affected the propensity to report: gender, occupation, and acknowledgment of the link between family violence and deliberate animal harm. This article discusses these variables and their implications.

Adjusting the specificity of an engine map based on the sensitivity of an engine control parameter relative to a performance variable

DOEpatents

Jiang, Li; Lee, Donghoon; Yilmaz, Hakan; Stefanopoulou, Anna

2014-10-28

Methods and systems for engine control optimization are provided. A first and a second operating condition of a vehicle engine are detected. An initial value is identified for a first and a second engine control parameter corresponding to a combination of the detected operating conditions according to a first and a second engine map look-up table. The initial values for the engine control parameters are adjusted based on a detected engine performance variable to cause the engine performance variable to approach a target value. A first and a second sensitivity of the engine performance variable are determined in response to changes in the engine control parameters. The first engine map look-up table is adjusted when the first sensitivity is greater than a threshold, and the second engine map look-up table is adjusted when the second sensitivity is greater than a threshold.

An Abstinence Program's Impact on Cognitive Mediators and Sexual Initiation

ERIC Educational Resources Information Center

Weed, Stan E.; Ericksen, Irene H.; Lewis, Allen; Grant, Gale E.; Wibberly, Kathy H.

2008-01-01

Objectives: To evaluate the impact of an abstinence education program on sexual intercourse initiation and on possible cognitive mediators of sexual initiation for virgin seventh graders in suburban Virginia. Methods: Measures of sexual behavior and 6 mediating variables were compared at 3 time periods for program participants and a matched…

Employability and personal initiative as antecedents of job satisfaction.

PubMed

Gamboa, Juan Pablo; Gracia, Francisco; Ripoll, Pilar; Peiró, José María

2009-11-01

In a changing and flexible labour market it is important to clarify the role of environmental and personal variables that contribute to obtaining adequate levels of job satisfaction. The aim of the present study is to analyze the direct effects of employability and personal initiative on intrinsic, extrinsic and social job satisfaction, clarifying their cumulative and interactive effects. The study has been carried out in a sample of 1319 young Spanish workers. Hypotheses were tested by means of the moderated hierarchical regression analysis. Results show that employability and personal initiative predict in a cumulative way the intrinsic, extrinsic and social job satisfaction. Moreover, the interaction between employability and personal initiative increases the prediction of these two variables on intrinsic and extrinsic job satisfaction. Results also indicate that higher values of employability when initiative is also high are associated to higher levels of intrinsic and extrinsic satisfaction. These results have implications for theory and practice in a context of new employment relations.

Predicting who will undergo surgery after physiotherapy for female stress urinary incontinence.

PubMed

Labrie, J; Lagro-Janssen, A L M; Fischer, K; Berghmans, L C M; van der Vaart, C H

2015-03-01

To predict who will undergo midurethral sling surgery (surgery) after initial pelvic floor muscle training (physiotherapy) for stress urinary incontinence in women. This was a cohort study including women with moderate to severe stress incontinence who were allocated to the physiotherapy arm from a previously reported multicentre trial comparing initial surgery or initial physiotherapy in treating stress urinary incontinence. Crossover to surgery was allowed. Data from 198/230 women who were randomized to physiotherapy was available for analysis, of whom 97/198 (49 %) crossed over to surgery. Prognostic factors for undergoing surgery after physiotherapy were age <55 years at baseline (OR 2.87; 95 % CI 1.30-6.32), higher educational level (OR 3.28; 95 % CI 0.80-13.47), severe incontinence at baseline according to the Sandvik index (OR 1.77; 95 % CI 0.95-3.29) and Urogenital Distress Inventory; incontinence domain score (OR 1.03; per point; 95 % CI 1.01-1.65). Furthermore, there was interaction between age <55 years and higher educational level (OR 0.09; 95 % CI 0.02-0.46). Using these variables we constructed a prediction rule to estimate the risk of surgery after initial physiotherapy. In women with moderate to severe stress incontinence, individual prediction for surgery after initial physiotherapy is possible, thus enabling shared decision making for the choice between initial conservative or invasive management of stress urinary incontinence.

Disease spread across multiple scales in a spatial hierarchy: effect of host spatial structure and of inoculum quantity and distribution.

PubMed

Gosme, Marie; Lucas, Philippe

2009-07-01

Spatial patterns of both the host and the disease influence disease spread and crop losses. Therefore, the manipulation of these patterns might help improve control strategies. Considering disease spread across multiple scales in a spatial hierarchy allows one to capture important features of epidemics developing in space without using explicitly spatialized variables. Thus, if the system under study is composed of roots, plants, and planting hills, the effect of host spatial pattern can be studied by varying the number of plants per planting hill. A simulation model based on hierarchy theory was used to simulate the effects of large versus small planting hills, low versus high level of initial infections, and aggregated versus uniform distribution of initial infections. The results showed that aggregating the initially infected plants always resulted in slower epidemics than spreading out the initial infections uniformly. Simulation results also showed that, in most cases, disease epidemics were slower in the case of large host aggregates (100 plants/hill) than with smaller aggregates (25 plants/hill), except when the initially infected plants were both numerous and spread out uniformly. The optimal strategy for disease control depends on several factors, including initial conditions. More importantly, the model offers a framework to account for the interplay between the spatial characteristics of the system, rates of infection, and aggregation of the disease.

Discovering the Listener within Us: The Impact of Trait-Like Personality Variables and Communicator Styles on Preferences for Listening Style

ERIC Educational Resources Information Center

Villaume, William A.; Bodie, Graham D.

2007-01-01

Extending past research, the present study provides an initial examination of the relationship between trait-like personality variables, communicator style, and individual listening preferences. A series of canonical correlations were run to ascertain to what degree certain communication preferences and trait-like personality variables are related…

Initial poststocking mortality, oxytetracycline marking, and year-class contribution of black-nosed crappies stocked into Tennessee reservoirs

USGS Publications Warehouse

Isermann, D.A.; Bettoli, P.W.; Sammons, S.M.; Churchill, T.N.

2002-01-01

Initial poststocking mortality, oxytetracycline mark persistence, and year-class contribution were evaluated for black-nosed crappies, a morphological variant of the black crappie Pomoxis nigromaculatus, stocked into Tennessee reservoirs during 1997-1999. Average initial poststocking mortality was low (x?? = 13%, N = 44). Lake temperature and the difference between lake and hauling tank water temperatures were significant in explaining variability in arcsine-transformed mortality estimates; however, the variability explained by these factors was low (R2 = 0.15). Oxytetracycline immersion was a highly effective marking tool; 97-100% of all crappies treated were marked, and 99% of the marks were visible 36-110 weeks after marking. All control otoliths were correctly scored as unmarked during the evaluation, and mortality rates did not differ between marked and unmarked crappies. Year-class contribution was variable across reservoirs and was highest in Normandy Reservoir (34-93% at ages 1-3). Contribution at ages 1 and 2 was 11-24% in Woods Reservoir. Stocking did not supplement the crappie population in Lake Graham. Black-nosed crappies made up a significant portion (>50%) of the crappies harvested by anglers in Center Hill Reservoir 3 years after stocking was initiated. Conversely, black-nosed crappies made up a relatively small percentage (???12%) of the crappies harvested in Cherokee Reservoir in the 4 years after initial stocking.

Locoregional disease patterns in well-differentiated and dedifferentiated retroperitoneal liposarcoma: implications for the extent of resection?

PubMed

Tseng, William W; Madewell, John E; Wei, Wei; Somaiah, Neeta; Lazar, Alexander J; Ghadimi, Markus P; Hoffman, Aviad; Pisters, Peter W T; Lev, Dina C; Pollock, Raphael E

2014-07-01

Well-differentiated (WD)/dedifferentiated (DD) liposarcoma is the most common soft tissue sarcoma of the retroperitoneum. The frequency of distant metastasis is low and the major burden of disease is locoregional. We sought to define the patterns of locoregional disease to help guide surgical decision making. Data were collected from 247 patients with de novo or recurrent tumors treated at our institution from 1993 to early 2012. The number and location of tumors at both initial presentation and subsequent locoregional recurrence were determined by combined analysis of operative dictations and radiologic imaging. Thirty-four percent of patients had multifocal locoregional disease (two or more tumors) at initial presentation to our institution, including 9 % who had tumors at synchronous remote retroperitoneal sites. The impact of multifocal disease on overall survival was dependent on histologic subtype (WD vs. DD) and disease presentation (de novo vs. recurrence) at the time of resection. Among patients with initial unifocal disease, 57 % progressed to multifocal locoregional disease with subsequent recurrence, including 11 % with new tumors outside of the original resection field. No clinicopathologic or treatment-related variable, including the type or extent of resection, was predictive of either multifocal or 'outside field' progression. Multifocal disease is common in patients with WD/DD retroperitoneal liposarcoma, and tumors can also develop at remote, locoregional sites. Surgical resection remains the primary method of locoregional control in this disease; however, the aggressiveness of resection should be individualized, with consideration of both tumor and patient-related factors.

[Influence of depression on the initial diagnosis and the evolution of cognitive impairment].

PubMed

Cenalmor-Aparicio, C; Bravo-Quelle, N; Miranda-Acuna, J; Luque-Buzo, E; Herrera-Tejedor, J; Olazaran-Rodriguez, J

2017-07-16

Depression and cognitive impairment maintain a close and complex relationship, which could be modified by pharmacological treatment. To analyze the influence of depression and antidepressive medication on the initial diagnosis and the evolution of cognitive impairment. All the patients derived to a Neurology clinic due to complaints or suspicion of cognitive impairment, during a period of nine years, were studied. The influence of demographic and depression-related variables on initial cognitive diagnosis, cognitive-functional situation and 1-year evolution were analyzed. A total of 582 patients were included (mean age: 77.6 ± 7.0; 64.9% women). Frequency of current and past depression were, respectively, 25.4% and 17.2%. In addition, 20.6% of the patients were taking antidepressant medication and 31.2% were on anxiolytic/hypnotic treatment. One-year follow-up visit was available in 320 (59.8%) of patients. In the adjusted analysis, anxiolytic/hypnotic treatment was associated with a worse cognitive-functional situation in the initial visit, while past depression and presence of dystimia were associated with a favorable evolution (p < 0.05). Past or current depression are not associated with bad prognosis in patients derived to neurologist due to possible cognitive impairment.

Systematic Review of Smoking Initiation among Asian Adolescents, 20052015: Utilizing the Frameworks of Triadic Influence and Planned Behavior.

PubMed

Talip, Tajidah; Murang, Zaidah; Kifli, Nurolaini; Naing, Lin

2016-01-01

A recent WHO data report on mortality attributable to tobacco use including cigarette smoking indicated a very high burden of deaths in Asia and that people often initiate smoking as early as young adolescents. The objectives of this study were to systematically review peerreviewed articles on cigarette smoking initiation among Asian adolescents and to develop a conceptual model of factors influencing smoking initiation by integrating all relevant factors based on existing data. Following a PRISMA guideline, a systematic review of articles published between 2005 and June 2015 was conducted using 5 databases on cigarette smoking initiation among adolescents (aged 1019 years) living in Asia. We summarized the main findings of each study according to our research questions and data that emerged during the data extraction process. Analysis and categorization were based on the TTI and TPB models and classification of factors extracted from the study, were as follows: personal factors, social factors, broader environmental factors, mediators, and intention to initiate smoking and smoking behavior. Of 1,227 identified studies, only 20 were included in this review. Our findings found that the mean age of cigarette smoking initiation ranged from 10 to 14 years and those who are more likely to initiate smoking are male, older adolescents, adolescents with low parental SES, individuals with low parental monitoring, low parental education level and having no discussion on smoking at home, those living in public housing and those exhibiting healthrisk behavior. Our study also revealed that the risk of smoking initiation increased when they are exposed to smokers, influenced by peers, exposed to tobacco advertisements, receive pocket money, have lack of knowledge about smoking, have poor school performance, have a family conflict and have psychological problems. The conceptual model developed demonstrated complex networks of factors influencing initiation. This systematic review presents various factors influencing smoking initiation of the Asian adolescents and provides a conceptual framework to further analyze factors. Future studies should have a standard measure of smoking initiation, should analyze interactions and the intensity of relationships between different factors or variables in the conceptual model. This will in turn consolidate the understanding of the different factors affecting smoking initiation and will help to improve interventions in this area.

The effects of initial participation motivations on learning engagement in transition training for future general practitioners in rural China: perceived deterrents as mediator

PubMed Central

Cui, Guan-yu; Yao, Mei-lin; Zhang, Xia; Guo, Yan-kui; Li, Hui-min; Yao, Xiu-ping

2016-01-01

Background For the shortage of high-quality general practitioners (GPs) in China's rural areas, Chinese government has taken steps to encourage rural specialists to participate in transition training for future GPs. Specialists’ initial participation motivations and their perceived deterrents during training may play important roles for their learning engagement in the transition training. This study aimed at revealing the relationships among the variables of initial participation motivations, perceived deterrents in training, and learning engagement. Methods A questionnaire survey was used in this study. A total of 156 rural specialists who participated in transition training for future GPs filled out the questionnaire, which consisted of the measurements of initial participation motivations, perceived deterrents, and learning engagement in training. The data about specialists’ demographic variables were collected at the same time. Results The variance of initial escape/stimulations motivation significantly predicted the variance of learning engagement through the full mediating role of perceived deterrents in training. In addition, initial educational preparation motivations predicted the variance of learning engagement directly. Conclusions Specialists’ initial participation motivations and perceived deterrents in training played important roles for learning engagement in the transition training. PMID:27340086

Effects of ocean initial perturbation on developing phase of ENSO in a coupled seasonal prediction model

NASA Astrophysics Data System (ADS)

Lee, Hyun-Chul; Kumar, Arun; Wang, Wanqiu

2018-03-01

Coupled prediction systems for seasonal and inter-annual variability in the tropical Pacific are initialized from ocean analyses. In ocean initial states, small scale perturbations are inevitably smoothed or distorted by the observational limits and data assimilation procedures, which tends to induce potential ocean initial errors for the El Nino-Southern Oscillation (ENSO) prediction. Here, the evolution and effects of ocean initial errors from the small scale perturbation on the developing phase of ENSO are investigated by an ensemble of coupled model predictions. Results show that the ocean initial errors at the thermocline in the western tropical Pacific grow rapidly to project on the first mode of equatorial Kelvin wave and propagate to the east along the thermocline. In boreal spring when the surface buoyancy flux weakens in the eastern tropical Pacific, the subsurface errors influence sea surface temperature variability and would account for the seasonal dependence of prediction skill in the NINO3 region. It is concluded that the ENSO prediction in the eastern tropical Pacific after boreal spring can be improved by increasing the observational accuracy of subsurface ocean initial states in the western tropical Pacific.

Hamiltonian models for the propagation of irrotational surface gravity waves over a variable bottom.

PubMed

Compelli, A; Ivanov, R; Todorov, M

2018-01-28

A single incompressible, inviscid, irrotational fluid medium bounded by a free surface and varying bottom is considered. The Hamiltonian of the system is expressed in terms of the so-called Dirichlet-Neumann operators. The equations for the surface waves are presented in Hamiltonian form. Specific scaling of the variables is selected which leads to approximations of Boussinesq and Korteweg-de Vries (KdV) types, taking into account the effect of the slowly varying bottom. The arising KdV equation with variable coefficients is studied numerically when the initial condition is in the form of the one-soliton solution for the initial depth.This article is part of the theme issue 'Nonlinear water waves'. © 2017 The Author(s).

Early symptom burden predicts recovery after sport-related concussion

PubMed Central

Mannix, Rebekah; Monuteaux, Michael C.; Stein, Cynthia J.; Bachur, Richard G.

2014-01-01

Objective: To identify independent predictors of and use recursive partitioning to develop a multivariate regression tree predicting symptom duration greater than 28 days after a sport-related concussion. Methods: We conducted a prospective cohort study of patients in a sports concussion clinic. Participants completed questionnaires that included the Post-Concussion Symptom Scale (PCSS). Participants were asked to record the date on which they last experienced symptoms. Potential predictor variables included age, sex, score on symptom inventories, history of prior concussions, performance on computerized neurocognitive assessments, loss of consciousness and amnesia at the time of injury, history of prior medical treatment for headaches, history of migraines, and family history of concussion. We used recursive partitioning analysis to develop a multivariate prediction model for identifying athletes at risk for a prolonged recovery from concussion. Results: A total of 531 patients ranged in age from 7 to 26 years (mean 14.6 ± 2.9 years). The mean PCSS score at the initial visit was 26 ± 26; mean time to presentation was 12 ± 5 days. Only total score on symptom inventory was independently associated with symptoms lasting longer than 28 days (adjusted odds ratio 1.044; 95% confidence interval [CI] 1.034, 1.054 for PCSS). No other potential predictor variables were independently associated with symptom duration or useful in developing the optimal regression decision tree. Most participants (86%; 95% CI 80%, 90%) with an initial PCSS score of <13 had resolution of their symptoms within 28 days of injury. Conclusions: The only independent predictor of prolonged symptoms after sport-related concussion is overall symptom burden. PMID:25381296

Initial Risk Analysis and Decision Making Framework

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

Engel, David W.

2012-02-01

Commercialization of new carbon capture simulation initiative (CCSI) technology will include two key elements of risk management, namely, technical risk (will process and plant performance be effective, safe, and reliable) and enterprise risk (can project losses and costs be controlled within the constraints of market demand to maintain profitability and investor confidence). Both of these elements of risk are incorporated into the risk analysis subtask of Task 7. Thus far, this subtask has developed a prototype demonstration tool that quantifies risk based on the expected profitability of expenditures when retrofitting carbon capture technology on a stylized 650 MW pulverized coalmore » electric power generator. The prototype is based on the selection of specific technical and financial factors believed to be important determinants of the expected profitability of carbon capture, subject to uncertainty. The uncertainty surrounding the technical performance and financial variables selected thus far is propagated in a model that calculates the expected profitability of investments in carbon capture and measures risk in terms of variability in expected net returns from these investments. Given the preliminary nature of the results of this prototype, additional work is required to expand the scope of the model to include additional risk factors, additional information on extant and proposed risk factors, the results of a qualitative risk factor elicitation process, and feedback from utilities and other interested parties involved in the carbon capture project. Additional information on proposed distributions of these risk factors will be integrated into a commercial implementation framework for the purpose of a comparative technology investment analysis.« less

Early symptom burden predicts recovery after sport-related concussion.

PubMed

Meehan, William P; Mannix, Rebekah; Monuteaux, Michael C; Stein, Cynthia J; Bachur, Richard G

2014-12-09

To identify independent predictors of and use recursive partitioning to develop a multivariate regression tree predicting symptom duration greater than 28 days after a sport-related concussion. We conducted a prospective cohort study of patients in a sports concussion clinic. Participants completed questionnaires that included the Post-Concussion Symptom Scale (PCSS). Participants were asked to record the date on which they last experienced symptoms. Potential predictor variables included age, sex, score on symptom inventories, history of prior concussions, performance on computerized neurocognitive assessments, loss of consciousness and amnesia at the time of injury, history of prior medical treatment for headaches, history of migraines, and family history of concussion. We used recursive partitioning analysis to develop a multivariate prediction model for identifying athletes at risk for a prolonged recovery from concussion. A total of 531 patients ranged in age from 7 to 26 years (mean 14.6 ± 2.9 years). The mean PCSS score at the initial visit was 26 ± 26; mean time to presentation was 12 ± 5 days. Only total score on symptom inventory was independently associated with symptoms lasting longer than 28 days (adjusted odds ratio 1.044; 95% confidence interval [CI] 1.034, 1.054 for PCSS). No other potential predictor variables were independently associated with symptom duration or useful in developing the optimal regression decision tree. Most participants (86%; 95% CI 80%, 90%) with an initial PCSS score of <13 had resolution of their symptoms within 28 days of injury. The only independent predictor of prolonged symptoms after sport-related concussion is overall symptom burden. © 2014 American Academy of Neurology.

Spatiotemporal analysis of the relationship between socioeconomic factors and stroke in the Portuguese mainland population under 65 years old.

PubMed

Oliveira, André; Cabral, António J R; Mendes, Jorge M; Martins, Maria R O; Cabral, Pedro

2015-11-04

Stroke risk has been shown to display varying patterns of geographic distribution amongst countries but also between regions of the same country. Traditionally a disease of older persons, a global 25% increase in incidence instead was noticed between 1990 and 2010 in persons aged 20-≤64 years, particularly in low- and medium-income countries. Understanding spatial disparities in the association between socioeconomic factors and stroke is critical to target public health initiatives aiming to mitigate or prevent this disease, including in younger persons. We aimed to identify socioeconomic determinants of geographic disparities of stroke risk in people <65 years old, in municipalities of mainland Portugal, and the spatiotemporal variation of the association between these determinants and stroke risk during two study periods (1992-1996 and 2002-2006). Poisson and negative binomial global regression models were used to explore determinants of disease risk. Geographically weighted regression (GWR) represents a distinctive approach, allowing estimation of local regression coefficients. Models for both study periods were identified. Significant variables included education attainment, work hours per week and unemployment. Local Poisson GWR models achieved the best fit and evidenced spatially varying regression coefficients. Spatiotemporal inequalities were observed in significant variables, with dissimilarities between men and women. This study contributes to a better understanding of the relationship between stroke and socioeconomic factors in the population <65 years of age, one age group seldom analysed separately. It can thus help to improve the targeting of public health initiatives, even more in a context of economic crisis.

Penetrating duodenal trauma: A 19-year experience.

PubMed

Schroeppel, Thomas J; Saleem, Kashif; Sharpe, John P; Magnotti, Louis J; Weinberg, Jordan A; Fischer, Peter E; Croce, Martin A; Fabian, Timothy C

2016-03-01

Multiple techniques are used for repair in duodenal injury ranging from simple suture repair for low-grade injuries to pancreaticoduodenectomy for complicated high-grade injuries. Drains, both intraluminal and extraluminal, are placed variably depending on associated injuries and confidence with the repair. It is our contention that a simplified approach to repair will limit complications and mortality. The major complication of duodenal leak (DL) was the outcome used to assess methods of repair in this study. After early deaths from associated vascular injuries were excluded, patients with a penetrating duodenal injury admitted during a 19-year period ending in 2014 constituted the study population. A total of 125 patients with penetrating duodenal injuries were included. Overall, the leak rate was 8% with two duodenal-related mortalities. No differences were seen in patients who had a DL as compared with no leak with respect to demographics, injury severity, or admission variables. Patients with DL were more likely to have a major vascular injury (60% vs. 23%, p = 0.02) and a combined pancreatic injury (70% vs. 31%, p = 0.03). No differences were identified by repair technique, location, or grade of injury. DLs were more likely to have an extraluminal drain (90% vs. 45%, p = 0.008). Primary suture repair should be the initial approach considered for most injuries. Major vascular injuries and concomintant pancreatic injuries were associated with most leaks; therefore, adjuncts to repair including intraluminal drainage and pyloric exclusion should be considered on the initial operation. Extraluminal drains should be avoided unless required for associated injuries. Therapeutic/care management study, level IV.

A mathematical function to evaluate surgical complexity of cleft lip and palate.

PubMed

Ortiz-Posadas, M R; Vega-Alvarado, L; Toni, B

2009-06-01

The objective of this work is to show the modeling of a similarity function adapted to the medical environment using the logical-combinatorial approach of pattern recognition theory, and its application comparing the condition of patients with congenital malformations in the lip and/or palate, which are called cleft-primary palate and/or cleft-secondary palate, respectively. The similarity function is defined by the comparison criteria determined for each variable, taking into account their type (qualitative or quantitative), their domain and their initial space representation. In all, we defined 18 variables, with their domains and six different comparison criteria (fuzzy and absolute difference type). The model includes, further, the importance of every variable as well as a weight which reflects the surgical complexity of the cleft. Likewise, the usefulness of this function is shown by calculating the similarity among three patients. This work was developed jointly with the Cleft Palate Team at the Reconstructive Surgery Service of the Pediatric Hospital of Tacubaya, which belongs to the Health Institute of the Federal District in Mexico City.

Nine time steps: ultra-fast statistical consistency testing of the Community Earth System Model (pyCECT v3.0)

NASA Astrophysics Data System (ADS)

Milroy, Daniel J.; Baker, Allison H.; Hammerling, Dorit M.; Jessup, Elizabeth R.

2018-02-01

The Community Earth System Model Ensemble Consistency Test (CESM-ECT) suite was developed as an alternative to requiring bitwise identical output for quality assurance. This objective test provides a statistical measurement of consistency between an accepted ensemble created by small initial temperature perturbations and a test set of CESM simulations. In this work, we extend the CESM-ECT suite with an inexpensive and robust test for ensemble consistency that is applied to Community Atmospheric Model (CAM) output after only nine model time steps. We demonstrate that adequate ensemble variability is achieved with instantaneous variable values at the ninth step, despite rapid perturbation growth and heterogeneous variable spread. We refer to this new test as the Ultra-Fast CAM Ensemble Consistency Test (UF-CAM-ECT) and demonstrate its effectiveness in practice, including its ability to detect small-scale events and its applicability to the Community Land Model (CLM). The new ultra-fast test facilitates CESM development, porting, and optimization efforts, particularly when used to complement information from the original CESM-ECT suite of tools.

Modeling of Rolling Element Bearing Mechanics: Computer Program Updates

NASA Technical Reports Server (NTRS)

Ryan, S. G.

1997-01-01

The Rolling Element Bearing Analysis System (REBANS) extends the capability available with traditional quasi-static bearing analysis programs by including the effects of bearing race and support flexibility. This tool was developed under contract for NASA-MSFC. The initial version delivered at the close of the contract contained several errors and exhibited numerous convergence difficulties. The program has been modified in-house at MSFC to correct the errors and greatly improve the convergence. The modifications consist of significant changes in the problem formulation and nonlinear convergence procedures. The original approach utilized sequential convergence for nested loops to achieve final convergence. This approach proved to be seriously deficient in robustness. Convergence was more the exception than the rule. The approach was changed to iterate all variables simultaneously. This approach has the advantage of using knowledge of the effect of each variable on each other variable (via the system Jacobian) when determining the incremental changes. This method has proved to be quite robust in its convergence. This technical memorandum documents the changes required for the original Theoretical Manual and User's Manual due to the new approach.

The impact of dance-aerobics training on the morpho-motor status in female high-schoolers.

PubMed

Viskić-Stalec, Natasa; Stalec, Janez; Katić, Ratko; Podvorac, Durda; Katović, Darko

2007-03-01

The aim of the study was to analyze the impact of special programmed physical education including dance, aerobics and rhythmic gymnastics on the development of motor and functional abilities and morphological characteristics of female fourth-grade high-schoolers in Zagreb. A total sample of 220 high-schoolers aged 16-18 years were divided into two groups: experimental group of 115 students attending the program composed of dance structures and aerobics, and control group of 105 students attending classic program of physical education. A set of 3 morphological variables, 6 motor variables and one functional variable were applied in both groups on three occasions during an academic year (initial, transient and final measurements). Two-factor analysis of variance (MANOVA repeated measure design) showed the experimental program to significantly influence the development of coordination/agility and specific rhythm coordination, functional aerobic ability, repetitive and explosive strength and flexibility, along with significant reduction of overweight and adipose tissue. Study results clearly indicate that the existing programs of physical education should be revised and replaced by more appropriate ones.

Influences of operational parameters on phosphorus removal in batch and continuous electrocoagulation process performance.

PubMed

Nguyen, Dinh Duc; Yoon, Yong Soo; Bui, Xuan Thanh; Kim, Sung Su; Chang, Soon Woong; Guo, Wenshan; Ngo, Huu Hao

2017-11-01

Performance of an electrocoagulation (EC) process in batch and continuous operating modes was thoroughly investigated and evaluated for enhancing wastewater phosphorus removal under various operating conditions, individually or combined with initial phosphorus concentration, wastewater conductivity, current density, and electrolysis times. The results revealed excellent phosphorus removal (72.7-100%) for both processes within 3-6 min of electrolysis, with relatively low energy requirements, i.e., less than 0.5 kWh/m 3 for treated wastewater. However, the removal efficiency of phosphorus in the continuous EC operation mode was better than that in batch mode within the scope of the study. Additionally, the rate and efficiency of phosphorus removal strongly depended on operational parameters, including wastewater conductivity, initial phosphorus concentration, current density, and electrolysis time. Based on experimental data, statistical model verification of the response surface methodology (RSM) (multiple factor optimization) was also established to provide further insights and accurately describe the interactive relationship between the process variables, thus optimizing the EC process performance. The EC process using iron electrodes is promising for improving wastewater phosphorus removal efficiency, and RSM can be a sustainable tool for predicting the performance of the EC process and explaining the influence of the process variables.

Study of the influence of sporulation conditions on heat resistance of Geobacillus stearothermophilus used in the development of biological indicators for steam sterilization.

PubMed

Guizelini, Belquis P; Vandenberghe, Luciana P S; Sella, Sandra Regina B R; Soccol, Carlos Ricardo

2012-12-01

Biological indicators are important tools in infection control via sterilization process monitoring. The use of a standardized spore crop with a well-defined heat resistance will guarantee the quality of a biological indicator. Ambient factors during sporulation can affect spore characteristics and properties, including heat resistance. The aim of this study is to evaluate the main sporulation factors responsible for heat resistance in Geobacillus stearothermophilus, a useful biological indicator for steam sterilization. A sequence of a three-step optimization of variables (initial pH, nutrient concentration, tryptone, peptone, beef extract, yeast extract, manganese sulfate, magnesium sulfate, calcium chloride and potassium phosphate) was carried out to screen those that have a significant influence on heat resistance of produced spores. The variable exerting greatest influence on G. stearothermophilus heat resistance during sporulation was found to be the initial pH. Lower nutrient concentration and alkaline pH around 8.5 tended to enhance decimal reduction time at 121 °C (D(121°C)). A central composite design enabled a fourfold enhancement in heat resistance, and the model obtained accurately describes positive pH and negative manganese sulfate concentration influence on spore heat resistance.

Potential determinants of efficacy of mirror therapy in stroke patients – A pilot study

PubMed Central

Brunetti, Maddalena; Morkisch, Nadine; Fritzsch, Claire; Mehnert, Jan; Steinbrink, Jens; Niedeggen, Michael; Dohle, Christian

2015-01-01

Abstract Background: Mirror therapy (MT) was found to improve motor function after stroke. However, there is high variability between patients regarding motor recovery. Objectives: The following pilot study was designed to identify potential factors determining this variability between patients with severe upper limb paresis, receiving MT. Methods: Eleven sub-acute stroke patients with severe upper limb paresis participated, receiving in-patient rehabilitation. After a set of pre-assessments (including measurement of brain activity at the primary motor cortex and precuneus during the mirror illusion, using near-infrared spectroscopy as described previously), four weeks of MT were applied, followed by a set of post-assessments. Discriminant group analysis for MT responders and non-responders was performed. Results: Six out of eleven patients were defined as responders and five as non-responders on the basis of their functional motor improvement. The initial motor function and the activity shift in both precunei (mirror index) were found to discriminate significantly between responders and non-responders. Conclusions: In line with earlier results, initial motor function was confirmed as crucial determinant of motor recovery. Additionally, activity response to the mirror illusion in both precunei was found to be a candidate for determination of the efficacy of MT. PMID:26409402

GeneratorSE: A Sizing Tool for Variable-Speed Wind Turbine Generators

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

Sethuraman, Latha; Dykes, Katherine L

This report documents a set of analytical models employed by the optimization algorithms within the GeneratorSE framework. The initial values and boundary conditions employed for the generation of the various designs and initial estimates for basic design dimensions, masses, and efficiency for the four different models of generators are presented and compared with empirical data collected from previous studies and some existing commercial turbines. These models include designs applicable for variable-speed, high-torque application featuring direct-drive synchronous generators and low-torque application featuring induction generators. In all of the four models presented, the main focus of optimization is electromagnetic design with themore » exception of permanent-magnet and wire-wound synchronous generators, wherein the structural design is also optimized. Thermal design is accommodated in GeneratorSE as a secondary attribute by limiting the winding current densities to acceptable limits. A preliminary validation of electromagnetic design was carried out by comparing the optimized magnetic loading against those predicted by numerical simulation in FEMM4.2, a finite-element software for analyzing electromagnetic and thermal physics problems for electrical machines. For direct-drive synchronous generators, the analytical models for the structural design are validated by static structural analysis in ANSYS.« less

Timing at peak force may be the hidden target controlled in continuation and synchronization tapping.

PubMed

Du, Yue; Clark, Jane E; Whitall, Jill

2017-05-01

Timing control, such as producing movements at a given rate or synchronizing movements to an external event, has been studied through a finger-tapping task where timing is measured at the initial contact between finger and tapping surface or the point when a key is pressed. However, the point of peak force is after the time registered at the tapping surface and thus is a less obvious but still an important event during finger tapping. Here, we compared the time at initial contact with the time at peak force as participants tapped their finger on a force sensor at a given rate after the metronome was turned off (continuation task) or in synchrony with the metronome (sensorimotor synchronization task). We found that, in the continuation task, timing was comparably accurate between initial contact and peak force. These two timing events also exhibited similar trial-by-trial statistical dependence (i.e., lag-one autocorrelation). However, the central clock variability was lower at the peak force than the initial contact. In the synchronization task, timing control at peak force appeared to be less variable and more accurate than that at initial contact. In addition to lower central clock variability, the mean SE magnitude at peak force (SEP) was around zero while SE at initial contact (SEC) was negative. Although SEC and SEP demonstrated the same trial-by-trial statistical dependence, we found that participants adjusted the time of tapping to correct SEP, but not SEC, toward zero. These results suggest that timing at peak force is a meaningful target of timing control, particularly in synchronization tapping. This result may explain the fact that SE at initial contact is typically negative as widely observed in the preexisting literature.

Spatiotemporal Patterns of Urban Trace Gases and Pollutants Observed with a Light Rail Vehicle Platform in Salt Lake City, UT

NASA Astrophysics Data System (ADS)

Mitchell, L.; Crosman, E.; Fasoli, B.; Leclair-Marzolf, L.; Jacques, A.; Horel, J.; Lin, J. C.; Bowling, D. R.; Ehleringer, J. R.

2015-12-01

Urban environments are characterized by both spatial complexity and temporal variability, each of which present challenges for measurement strategies aimed at constraining estimates of greenhouse gas emissions and air quality. To address these challenges we initiated a project in December 2014 to measure trace species (CO2, CH4, O3, and Particulate Matter) by way of a Utah Transit Authority (UTA) light rail vehicle whose route traverses the Salt Lake Valley in Utah on an hourly basis, retracing the same route through commercial, residential, suburban, and rural typologies. Light rail vehicles present advantages as a measurement platform, including the absence of in-situ fossil fuel emissions, repeated transects across a urban region that provides both spatial and temporal information, and relatively low operating costs. We present initial results from the first year of operations including the spatiotemporal patterns of greenhouse gases and pollutants across Salt Lake City, UT with an emphasis on criteria pollutants, identification of sources, and future applications of this measurement platform.

Management of failure after surgery for gastro-esophageal reflux disease.

PubMed

Gronnier, C; Degrandi, O; Collet, D

2018-04-01

Surgical treatment of gastro-esophageal reflux disease (ST-GERD) is well-codified and offers an alternative to long-term medical treatment with a better efficacy for short and long-term outcomes. However, failure of ST-GERD is observed in 2-20% of patients; management is challenging and not standardized. The aim of this study is to analyze the causes of failure and to provide a treatment algorithm. The clinical aspects of ST-GERD failure are variable including persistent reflux, dysphagia or permanent discomfort leading to an important degradation of the quality of life. A morphological and functional pre-therapeutic evaluation is necessary to: (i) determine whether the symptoms are due to recurrence of reflux or to an error in initial indication and (ii) to understand the cause of the failure. The most frequent causes of failure of ST-GERD include errors in the initial indication, which often only need medical treatment, and surgical technical errors, for which surgical redo surgery can be difficult. Multidisciplinary management is necessary in order to offer the best-adapted treatment. Copyright © 2018. Published by Elsevier Masson SAS.

Opportunities for social workers in the patient centered medical home.

PubMed

Hawk, Mary; Ricci, Edmund; Huber, George; Myers, Marcella

2015-01-01

The Patient Centered Medical Home (PCMH) has been hailed as one method of improving chronic care outcomes in the United States. A number of studies have underscored the importance of the social work role within the PCMH, yet little existing research explores the social worker as a driver of improved patient care. The Pennsylvania Chronic Care Initiative was created with a primary goal of increasing the number of practices that were recognized as PCMH by the National Committee for Quality Assurance. This article describes findings from in-depth qualitative interviews with representatives from seven primary care practices, in which the authors examined barriers and facilitators to implementation of the initiative. Barriers to implementation included small practice size, payer-driven care, not having a strong physician champion, variability within patient populations, and high implementation costs. Facilitators included having a social worker coordinate behavioral health services, clinical nurse case managers, preexisting models of outcomes-driven care, and being part of an integrated health delivery and financing system. Recommendations strengthening the role of medical social workers in primary care practices are discussed.

Bidirectional Relationships Between Fatigue and Everyday Experiences in Persons Living With HIV.

PubMed

Cook, Paul F; Hartson, Kimberly R; Schmiege, Sarah J; Jankowski, Catherine; Starr, Whitney; Meek, Paula

2016-06-01

Fatigue symptoms are very common among persons living with HIV (PLWH). Fatigue is related to functional and psychological problems and to treatment nonadherence. Using secondary data from ecological momentary assessment, we examined fatigue as a predictor of PLWH everyday experiences. In bidirectional analyses based on the shape shifters model, we also examined these experiences as predictors of fatigue. Data were examined from 67 PLWH who completed daily surveys on a handheld computer. Brief validated scales were used to assess participants' control beliefs, mood, stress, coping, social support, experience of stigma, and motivation. At the beginning and end of the study, fatigue was measured with two CES-D items that have been used in past HIV symptom research. Multilevel models and logistic regression were used to test reciprocal predictive relationships between variables. Moderate to severe fatigue affected 45% of PLWH in the study. Initial fatigue predicted PLWH subsequent overall level of control beliefs, mood, stress, coping, and social support, all p < .05. These state variables remained relatively constant over time, regardless of participants' initial fatigue. In tests for reciprocal relationships with 33 PLWH, average daily stress, OR = 4.74, and stigma, OR = 4.86, also predicted later fatigue. Fatigue predicted several daily survey variables including stress and social support. Stress and support in turn predicted fatigue at a later time, suggesting a self-perpetuating cycle but also a possible avenue for intervention. Future studies should examine daily variation in fatigue among PLWH and its relation to other everyday experiences and behaviors. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Financial incentives to discontinue long-term benzodiazepine use: a discrete choice experiment investigating patient preferences and willingness to participate

PubMed Central

Marti, Joachim; Bachhuber, Marcus; Feingold, Jordyn; Meads, David; Richards, Michael; Hennessy, Sean

2017-01-01

Objectives Investigate the acceptability of financial incentives for initiating a medically supervised benzodiazepine discontinuation programme among people with long-term benzodiazepine use and to identify programme features that influence willingness to participate. Methods We conducted a discrete choice experiment in which we presented a variety of incentive-based programs to a sample of older adults with long-term benzodiazepine use identified using the outpatient electronic health record of a university-owned health system. We studied four programme variables: incentive amount for initiating the programme, incentive amount for successful benzodiazepine discontinuation, lottery versus certain payment and whether partial payment was given for dose reduction. Respondents reported their willingness to participate in the programmes and additional information was collected on demographics, history of use and anxiety symptoms. Results The overall response rate was 28.4%. Among the 126 respondents, all four programme variables influenced stated preferences. Respondents strongly preferred guaranteed cash-based incentives as opposed to a lottery, and the dollar amount of both the starting and conditional incentives had a substantial impact on choice. Willingness to participate increased with the amount of conditional incentive. Programme participation also varied by gender, duration of use and income. Conclusions Participation in an incentive-based benzodiazepine discontinuation programme might be relatively low, but is modifiable by programme variables including incentive amounts. These results will be helpful to inform the design of future trials of benzodiazepine discontinuation programmes. Further research is needed to assess the financial viability and potential cost-effectiveness of such economic incentives. PMID:28988167

The CESM Large Ensemble Project: Inspiring New Ideas and Understanding

NASA Astrophysics Data System (ADS)

Kay, J. E.; Deser, C.

2016-12-01

While internal climate variability is known to affect climate projections, its influence is often underappreciated and confused with model error. Why? In general, modeling centers contribute a small number of realizations to international climate model assessments [e.g., phase 5 of the Coupled Model Intercomparison Project (CMIP5)]. As a result, model error and internal climate variability are difficult, and at times impossible, to disentangle. In response, the Community Earth System Model (CESM) community designed the CESM Large Ensemble (CESM-LE) with the explicit goal of enabling assessment of climate change in the presence of internal climate variability. All CESM-LE simulations use a single CMIP5 model (CESM with the Community Atmosphere Model, version 5). The core simulations replay the twenty to twenty-first century (1920-2100) 40+ times under historical and representative concentration pathway 8.5 external forcing with small initial condition differences. Two companion 2000+-yr-long preindustrial control simulations (fully coupled, prognostic atmosphere and land only) allow assessment of internal climate variability in the absence of climate change. Comprehensive outputs, including many daily fields, are available as single-variable time series on the Earth System Grid for anyone to use. Examples of scientists and stakeholders that are using the CESM-LE outputs to help interpret the observational record, to understand projection spread and to plan for a range of possible futures influenced by both internal climate variability and forced climate change will be highlighted the presentation.

Response of western mountain ecosystems to climatic variability and change: The Western Mountain Initiative

USGS Publications Warehouse

Stephenson, Nathan L.; Peterson, Dave; Fagre, Daniel B.; Allen, Craig D.; McKenzie, Donald; Baron, Jill S.; O'Brian, Kelly

2007-01-01

Mountain ecosystems within our national parks and other protected areas provide valuable goods and services such as clean water, biodiversity conservation, and recreational opportunities, but their potential responses to expected climatic changes are inadequately understood. The Western Mountain Initiative (WMI) is a collaboration of scientists whose research focuses on understanding and predicting responses of western mountain ecosystems to climatic variability and change. It is a legacy of the Global Change Research Program initiated by the National Park Service (NPS) in 1991 and continued by the U.S. Geological Survey (USGS) to this day as part of the U.S. Climate Change Science Program (http://www.climatescience.gov/). All WMI scientists are active participants in CIRMOUNT, and seek to further its goals.

Relationship between Defect Size and Fatigue Life Distributions in Al-7 Pct Si-Mg Alloy Castings

NASA Astrophysics Data System (ADS)

Tiryakioğlu, Murat

2009-07-01

A new method for predicting the variability in fatigue life of castings was developed by combining the size distribution for the fatigue-initiating defects and a fatigue life model based on the Paris-Erdoğan law for crack propagation. Two datasets for the fatigue-initiating defects in Al-7 pct Si-Mg alloy castings, reported previously in the literature, were used to demonstrate that (1) the size of fatigue-initiating defects follow the Gumbel distribution; (2) the crack propagation model developed previously provides respectable fits to experimental data; and (3) the method developed in the present study expresses the variability in both datasets, almost as well as the lognormal distribution and better than the Weibull distribution.

Latin Hypercube Sampling (LHS) at variable resolutions for enhanced watershed scale Soil Sampling and Digital Soil Mapping.

NASA Astrophysics Data System (ADS)

Hamalainen, Sampsa; Geng, Xiaoyuan; He, Juanxia

2017-04-01

Latin Hypercube Sampling (LHS) at variable resolutions for enhanced watershed scale Soil Sampling and Digital Soil Mapping. Sampsa Hamalainen, Xiaoyuan Geng, and Juanxia, He. AAFC - Agriculture and Agr-Food Canada, Ottawa, Canada. The Latin Hypercube Sampling (LHS) approach to assist with Digital Soil Mapping has been developed for some time now, however the purpose of this work was to complement LHS with use of multiple spatial resolutions of covariate datasets and variability in the range of sampling points produced. This allowed for specific sets of LHS points to be produced to fulfil the needs of various partners from multiple projects working in the Ontario and Prince Edward Island provinces of Canada. Secondary soil and environmental attributes are critical inputs that are required in the development of sampling points by LHS. These include a required Digital Elevation Model (DEM) and subsequent covariate datasets produced as a result of a Digital Terrain Analysis performed on the DEM. These additional covariates often include but are not limited to Topographic Wetness Index (TWI), Length-Slope (LS) Factor, and Slope which are continuous data. The range of specific points created in LHS included 50 - 200 depending on the size of the watershed and more importantly the number of soil types found within. The spatial resolution of covariates included within the work ranged from 5 - 30 m. The iterations within the LHS sampling were run at an optimal level so the LHS model provided a good spatial representation of the environmental attributes within the watershed. Also, additional covariates were included in the Latin Hypercube Sampling approach which is categorical in nature such as external Surficial Geology data. Some initial results of the work include using a 1000 iteration variable within the LHS model. 1000 iterations was consistently a reasonable value used to produce sampling points that provided a good spatial representation of the environmental attributes. When working within the same spatial resolution for covariates, however only modifying the desired number of sampling points produced, the change of point location portrayed a strong geospatial relationship when using continuous data. Access to agricultural fields and adjacent land uses is often "pinned" as the greatest deterrent to performing soil sampling for both soil survey and soil attribute validation work. The lack of access can be a result of poor road access and/or difficult geographical conditions to navigate for field work individuals. This seems a simple yet continuous issue to overcome for the scientific community and in particular, soils professionals. The ability to assist with the ease of access to sampling points will be in the future a contribution to the Latin Hypercube Sampling (LHS) approach. By removing all locations in the initial instance from the DEM, the LHS model can be restricted to locations only with access from the adjacent road or trail. To further the approach, a road network geospatial dataset can be included within spatial Geographic Information Systems (GIS) applications to access already produced points using a shortest-distance network method.

Variable Order and Distributed Order Fractional Operators

NASA Technical Reports Server (NTRS)

Lorenzo, Carl F.; Hartley, Tom T.

2002-01-01

Many physical processes appear to exhibit fractional order behavior that may vary with time or space. The continuum of order in the fractional calculus allows the order of the fractional operator to be considered as a variable. This paper develops the concept of variable and distributed order fractional operators. Definitions based on the Riemann-Liouville definitions are introduced and behavior of the operators is studied. Several time domain definitions that assign different arguments to the order q in the Riemann-Liouville definition are introduced. For each of these definitions various characteristics are determined. These include: time invariance of the operator, operator initialization, physical realization, linearity, operational transforms. and memory characteristics of the defining kernels. A measure (m2) for memory retentiveness of the order history is introduced. A generalized linear argument for the order q allows the concept of "tailored" variable order fractional operators whose a, memory may be chosen for a particular application. Memory retentiveness (m2) and order dynamic behavior are investigated and applications are shown. The concept of distributed order operators where the order of the time based operator depends on an additional independent (spatial) variable is also forwarded. Several definitions and their Laplace transforms are developed, analysis methods with these operators are demonstrated, and examples shown. Finally operators of multivariable and distributed order are defined in their various applications are outlined.

Analysis of watershed topography effects on summer precipitation variability in the southwestern United States

NASA Astrophysics Data System (ADS)

Sohoulande Djebou, Dagbegnon C.; Singh, Vijay P.; Frauenfeld, Oliver W.

2014-04-01

With climate change, precipitation variability is projected to increase. The present study investigates the potential interactions between watershed characteristics and precipitation variability. The watershed is considered as a functional unit that may impact seasonal precipitation. The study uses historical precipitation data from 370 meteorological stations over the last five decades, and digital elevation data from regional watersheds in the southwestern United States. This domain is part of the North American Monsoon region, and the summer period (June-July-August, JJA) was considered. Based on an initial analysis for 1895-2011, the JJA precipitation accounts, on average, for 22-43% of the total annual precipitation, with higher percentages in the arid part of the region. The unique contribution of this research is that entropy theory is used to address precipitation variability in time and space. An entropy-based disorder index was computed for each station's precipitation record. The JJA total precipitation and number of precipitation events were considered in the analysis. The precipitation variability potentially induced by watershed topography was investigated using spatial regionalization combining principal component and cluster analysis. It was found that the disorder in precipitation total and number of events tended to be higher in arid regions. The spatial pattern showed that the entropy-based variability in precipitation amount and number of events gradually increased from east to west in the southwestern United States. Regarding the watershed topography influence on summer precipitation patterns, hilly relief has a stabilizing effect on seasonal precipitation variability in time and space. The results show the necessity to include watershed topography in global and regional climate model parameterizations.

Extralinguistic speech characteristics of children with conduct and anxiety disorders.

PubMed

Kotsopoulos, S; Mellor, C

1986-01-01

Nine children with conduct and nine with anxiety disorder participated in the study. The subjects were requested to respond to verbal tasks (counting, picture description, story telling). Disturbance of conduct was associated with short initial hesitation before speaking. It is suggested that the initial hesitation variables are measures of reflection and cognitive planning. Anxiety across subjects was associated with increased breath rate and lower output of speech per breath. It is suggested speech breath variables are reliable measures of anxiety. Implication for the diagnosis and management of child psychiatric disorders are discussed.

Global existence of weak solutions to dissipative transport equations with nonlocal velocity

NASA Astrophysics Data System (ADS)

Bae, Hantaek; Granero-Belinchón, Rafael; Lazar, Omar

2018-04-01

We consider 1D dissipative transport equations with nonlocal velocity field: where is a nonlocal operator given by a Fourier multiplier. We especially consider two types of nonlocal operators: (1) , the Hilbert transform, (2) . In this paper, we show several global existence of weak solutions depending on the range of γ, δ and α. When , we take initial data having finite energy, while we take initial data in weighted function spaces (in the real variables or in the Fourier variables), which have infinite energy, when .

The Butterflies of Principal Components: A Case of Ultrafine-Grained Polyphase Units

NASA Astrophysics Data System (ADS)

Rietmeijer, F. J. M.

1996-03-01

Dusts in the accretion regions of chondritic interplanetary dust particles [IDPs] consisted of three principal components: carbonaceous units [CUs], carbon-bearing chondritic units [GUs] and carbon-free silicate units [PUs]. Among others, differences among chondritic IDP morphologies and variable bulk C/Si ratios reflect variable mixtures of principal components. The spherical shapes of the initially amorphous principal components remain visible in many chondritic porous IDPs but fusion was documented for CUs, GUs and PUs. The PUs occur as coarse- and ultrafine-grained units that include so called GEMS. Spherical principal components preserved in an IDP as recognisable textural units have unique proporties with important implications for their petrological evolution from pre-accretion processing to protoplanet alteration and dynamic pyrometamorphism. Throughout their lifetime the units behaved as closed-systems without chemical exchange with other units. This behaviour is reflected in their mineralogies while the bulk compositions of principal components define the environments wherein they were formed.

Understanding the Complexity of Temperature Dynamics in Xinjiang, China, from Multitemporal Scale and Spatial Perspectives

PubMed Central

Chen, Yaning; Li, Weihong; Liu, Zuhan; Wei, Chunmeng; Tang, Jie

2013-01-01

Based on the observed data from 51 meteorological stations during the period from 1958 to 2012 in Xinjiang, China, we investigated the complexity of temperature dynamics from the temporal and spatial perspectives by using a comprehensive approach including the correlation dimension (CD), classical statistics, and geostatistics. The main conclusions are as follows (1) The integer CD values indicate that the temperature dynamics are a complex and chaotic system, which is sensitive to the initial conditions. (2) The complexity of temperature dynamics decreases along with the increase of temporal scale. To describe the temperature dynamics, at least 3 independent variables are needed at daily scale, whereas at least 2 independent variables are needed at monthly, seasonal, and annual scales. (3) The spatial patterns of CD values at different temporal scales indicate that the complex temperature dynamics are derived from the complex landform. PMID:23843732

CosmoQuest Transient Tracker: Opensource Photometry & Astrometry software

NASA Astrophysics Data System (ADS)

Myers, Joseph L.; Lehan, Cory; Gay, Pamela; Richardson, Matthew; CosmoQuest Team

2018-01-01

CosmoQuest is moving from online citizen science, to observational astronomy with the creation of Transient Trackers. This open source software is designed to identify asteroids and other transient/variable objects in image sets. Transient Tracker’s features in final form will include: astrometric and photometric solutions, identification of moving/transient objects, identification of variable objects, and lightcurve analysis. In this poster we present our initial, v0.1 release and seek community input.This software builds on the existing NIH funded ImageJ libraries. Creation of this suite of opensource image manipulation routines is lead by Wayne Rasband and is released primarily under the MIT license. In this release, we are building on these libraries to add source identification for point / point-like sources, and to do astrometry. Our materials released under the Apache 2.0 license on github (http://github.com/CosmoQuestTeam) and documentation can be found at http://cosmoquest.org/TransientTracker.

Long-term functional outcome after unilateral cordectomy.

PubMed

Keilmann, Annerose; Napiontek, Ulrike; Engel, Christiane; Nakarat, Todsaporn; Schneider, Astrid; Mann, Wolf

2011-01-01

Our aim was to longitudinally analyze the vocal outcome after endoscopic CO(2) laser resection of early glottic carcinoma. Sixteen patients treated with laser surgery for T1 or T2 tumors of the vocal cords received voice therapy and were examined 1, 2, 3, 4.5, 6 and 12 months postoperatively. Besides videolaryngostroboscopy, each examination included history, phonetogram of the speaking and the singing voice, language-specific hoarseness diagram and a questionnaire (Voice Handicap Index 12 in German). Objective parameters demonstrated a broad variability with a slight tendency of improvement over time. For the maximal phonation time a nearly constant improvement was seen. After an initial improvement deterioration for subjective assessment in the Voice Handicap Index was noted in most patients 3-6 months postoperatively. The functional outcome after cordectomy is variable. MESSAGE OF THE PAPER: Discrepancies between objective findings and patient satisfaction over time have to be considered after cordectomy. Copyright © 2010 S. Karger AG, Basel.

Time Domain Astrochemistry in Protoplanetary Disks

NASA Astrophysics Data System (ADS)

Cleeves, Lauren Ilsedore

2018-01-01

The chemistry of protoplanetary disks sets the initial composition of newly formed planets and may regulate the efficiency by which planets form. Disk chemical abundances typically evolve over timescales spanning thousands if not millions of years. Consequently, it was a surprise when ALMA observations taken over the course of a single year showed significantly variable emission in H13CO+ relative to the otherwise constant thermal dust emission in the IM Lup protoplanetary disk. HCO+ is a known X-ray sensitive molecule, and by using simple time-evolving chemical models including stellar activity, we demonstrate that stellar X-ray flares are a viable explanation for the observed H13CO+ variability. If this link between chemistry and stellar activity is confirmed, simultaneous observations can provide a new tool to measure (and potentially map) fundamental disk parameters, such as electron density, as the light from X-ray flares propagates across the disk.

SkyDOT: a publicly accessible variability database, containing multiple sky surveys and real-time data

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

Starr, D. L.; Wozniak, P. R.; Vestrand, W. T.

2002-01-01

SkyDOT (Sky Database for Objects in Time-Domain) is a Virtual Observatory currently comprised of data from the RAPTOR, ROTSE I, and OGLE I1 survey projects. This makes it a very large time domain database. In addition, the RAPTOR project provides SkyDOT with real-time variability data as well as stereoscopic information. With its web interface, we believe SkyDOT will be a very useful tool for both astronomers, and the public. Our main task has been to construct an efficient relational database containing all existing data, while handling a real-time inflow of data. We also provide a useful web interface allowing easymore » access to both astronomers and the public. Initially, this server will allow common searches, specific queries, and access to light curves. In the future we will include machine learning classification tools and access to spectral information.« less

Factors affecting the use and perceived benefit of ITE and BTE hearing aids.

PubMed

Baumfield, A; Dillon, H

2001-08-01

The aim of the present study was to investigate factors that might affect hearing aid use, satisfaction and perceived benefit. A further aim was to look at which variables affect the choice of hearing aid, in particular, an in-the-ear (ITE) versus a behind-the-ear (BTE) device. Twenty-nine elderly hearing-impaired people with a mild-to-moderate hearing loss were fitted with both an ITE and a BTE hearing aid with similar electroacoustic performance. Both hearing aids were linear with output compression limiting and were fitted in a randomized order. After wearing each device for a six-week period, subj ets were asked to select the hearing aid they preferred. Variables significantly related to hearing aid choice, use and perceived benefit included ease of management, accuracy with which the NAL-R insertion gain target was achieved, earmould comfort and the type of hearing aid the client preferred initially.

Asteroseismology - The impact of solar space observations

NASA Technical Reports Server (NTRS)

Hudson, H. S.

1993-01-01

Observations from space relevant to solar global properties (oscillations, magnetic activity, etc.) are helpful both scientifically and technically in preparing for stellar observations. This paper summarizes the results from the main previous experiments (ACRIM, SOUP, and IPHIR), and also gives an initial technical report from the SXT instrument on board Yohkoh, launched in August 1991. The solar observations to date demonstrate the existence of several mechanisms for low-level variability: spots, faculae, the photospheric network, granulation, and p-mode oscillations. The observations of oscillations have been particularly helpful in setting limits on solar interior rotation. In addition to the solar processes, stars of other types may have different mechanisms of variability. These may include the analogs of coronal holes or solar flares, modes of oscillation not detected in the sun, collisions with small bodies, duplicity, and probably mechanisms not invented yet but related in interesting ways to stellar convection and magnetism.

Variable Stars as an Introduction to Computational Research

NASA Astrophysics Data System (ADS)

Cash, Jennifer; Walter, Donald K.

2017-01-01

As a part of larger effort to enhance the research activity at SC State and involve more undergraduates in research activities, we present our efforts to develop an introductory research experience where the goal is a balance of astrophysical understanding, general research skills, and programming skills which the students can carry into a wide variety of future research activities. We have found that variable stars are a very good topic for this sort of introductory experience due to a combination of factors including: accessibility of data, easily understandable physical processes, and a relatively straight forward data analysis process. We will present an outline of our research experiences to guide a student from the very initial stages of learning to final presentation of the student's work.“This work was supported in part by NSF PAARE award AST-1358913 and NSF HBCU-UP award HRD-1332449 to SCSU.”

Evaluation of the effect of process variables on the fatty acid profile of single cell oil produced by Mortierella using solid-state fermentation.

PubMed

Asadi, Seyedeh Zeinab; Khosravi-Darani, Kianoush; Nikoopour, Houshang; Bakhoda, Hossein

2015-03-01

This article reviews some of the aspects of single cell oil (SCO) production using solid-state fermentation (SSF) by fungi of the genus Mortierella. This article provides an overview of the advantages of SSF for SCO formation by the aforementioned fungus and demonstrates that the content of the polyunsaturated fatty acids (PUFA) depend on the type of fermentation media and culture conditions. Process variables that influence lipid accumulation by Mortierella spp. and the profile of the fatty acids are discussed, including incubation temperature, time, aeration, growth phase of the mycelium, particle size of the substrate, carbon to nitrogen ratio, initial moisture content and pH as well as supplementation of the substrate with nitrogen and oil. Finally, the article highlights future research trends for the scaled-up production of PUFAs in SSF.

Climate Projections and Uncertainty Communication.

PubMed

Joslyn, Susan L; LeClerc, Jared E

2016-01-01

Lingering skepticism about climate change might be due in part to the way climate projections are perceived by members of the public. Variability between scientists' estimates might give the impression that scientists disagree about the fact of climate change rather than about details concerning the extent or timing. Providing uncertainty estimates might clarify that the variability is due in part to quantifiable uncertainty inherent in the prediction process, thereby increasing people's trust in climate projections. This hypothesis was tested in two experiments. Results suggest that including uncertainty estimates along with climate projections leads to an increase in participants' trust in the information. Analyses explored the roles of time, place, demographic differences (e.g., age, gender, education level, political party affiliation), and initial belief in climate change. Implications are discussed in terms of the potential benefit of adding uncertainty estimates to public climate projections. Copyright © 2015 Cognitive Science Society, Inc.

Variation in Red Blood Cell Transfusion Practices During Cardiac Operations Among Centers in Maryland: Results From a State Quality-Improvement Collaborative.

PubMed

Magruder, J Trent; Blasco-Colmenares, Elena; Crawford, Todd; Alejo, Diane; Conte, John V; Salenger, Rawn; Fonner, Clifford E; Kwon, Christopher C; Bobbitt, Jennifer; Brown, James M; Nelson, Mark G; Horvath, Keith A; Whitman, Glenn R

2017-01-01

Variation in red blood cell (RBC) transfusion practices exists at cardiac surgery centers across the nation. We tested the hypothesis that significant variation in RBC transfusion practices between centers in our state's cardiac surgery quality collaborative remains even after risk adjustment. Using a multiinstitutional statewide database created by the Maryland Cardiac Surgery Quality Initiative (MCSQI), we included patient-level data from 8,141 patients undergoing isolated coronary artery bypass (CAB) or aortic valve replacement at 1 of 10 centers. Risk-adjusted multivariable logistic regression models were constructed to predict the need for any intraoperative RBC transfusion, as well as for any postoperative RBC transfusion, with anonymized center number included as a factor variable. Unadjusted intraoperative RBC transfusion probabilities at the 10 centers ranged from 13% to 60%; postoperative RBC transfusion probabilities ranged from 16% to 41%. After risk adjustment with demographic, comorbidity, and operative data, significant intercenter variability was documented (intraoperative probability range, 4% -59%; postoperative probability range, 13%-39%). When stratifying patients by preoperative hematocrit quartiles, significant variability in intraoperative transfusion probability was seen among all quartiles (lowest quartile: mean hematocrit value, 30.5% ± 4.1%, probability range, 17%-89%; highest quartile: mean hematocrit value, 44.8% ± 2.5%; probability range, 1%-35%). Significant variation in intercenter RBC transfusion practices exists for both intraoperative and postoperative transfusions, even after risk adjustment, among our state's centers. Variability in intraoperative RBC transfusion persisted across quartiles of preoperative hematocrit values. Copyright © 2017 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.

Agenda of the Fourth Annual Summer Conference, NASA/USRA University Advanced Design Program

NASA Technical Reports Server (NTRS)

1988-01-01

Presentations given by the participants at the fourth annual summer conference of the NASA/USRA University Advanced Design Program are summarized. The study topics include potential space and aeronautics projects which could be undertaken during a 20 to 30 year period beginning with the Space Station Initial Operating Configuration (IOC) scheduled for the early to mid-1990's. This includes system design studies for both manned and unmanned endeavors; e.g., lunar launch and landing facilities and operations, variable artificial gravity facility for the Space Station, manned Mars aircraft and delivery system, long term space habitat, construction equipment for lunar bases, Mars oxygen production system, trans-Pacific high speed civil transport, V/STOL aircraft concepts, etc.

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

Bhattacherjee, Biplob; Mukhopadhyay, Satyanarayan; Nojiri, Mihoko M.

Here, we study the impact of including quark- and gluon-initiated jet discrimination in the search for strongly interacting supersymmetric particles at the LHC. Taking the example of gluino pair production, considerable improvement is observed in the LHC search reach on including the jet substructure observables to the standard kinematic variables within a multivariate analysis. In particular, quark and gluon jet separation has higher impact in the region of intermediate mass-gap between the gluino and the lightest neutralino, as the difference between the signal and the standard model background kinematic distributions is reduced in this region. We also compare the predictionsmore » from different Monte Carlo event generators to estimate the uncertainty originating from the modelling of the parton shower and hadronization processes.« less

Integrated hydrologic modeling: Effects of spatial scale, discretization and initialization

NASA Astrophysics Data System (ADS)

Seck, A.; Welty, C.; Maxwell, R. M.

2011-12-01

Groundwater discharge contributes significantly to the annual flows of Chesapeake Bay tributaries and is presumed to contribute to the observed lag time between the implementation of management actions and the environmental response in the Chesapeake Bay. To investigate groundwater fluxes and flow paths and interaction with surface flow, we have developed a fully distributed integrated hydrologic model of the Chesapeake Bay Watershed using ParFlow. Here we present a comparison of model spatial resolution and initialization methods. We have studied the effect of horizontal discretization on overland flow processes at a range of scales. Three nested model domains have been considered: the Monocacy watershed (5600 sq. km), the Potomac watershed (92000 sq. km) and the Chesapeake Bay watershed (400,000 sq. km). Models with homogeneous subsurface and topographically-derived slopes were evaluated at 500-m, 1000-m, 2000-m, and 4000-m grid resolutions. Land surface slopes were derived from resampled DEMs and corrected using stream networks. Simulation results show that the overland flow processes are reasonably well represented with a resolution up to 2000 m. We observe that the effects of horizontal resolution dissipate with larger scale models. Using a homogeneous model that includes subsurface and surface terrain characteristics, we have evaluated various initialization methods for the integrated Monocacy watershed model. This model used several options for water table depths and two rainfall forcing methods including (1) a synthetic rainfall-recession cycle corresponding to the region's average annual rainfall rate, and (2) an initial shut-off of rainfall forcing followed by a rainfall-recession cycling. Results show the dominance of groundwater generated runoff during a first phase of the simulation followed by a convergence towards more balanced runoff generation mechanisms. We observe that the influence of groundwater runoff increases in dissected relief areas characterized by high slope magnitudes. This is due to the increase in initial water table gradients in these regions. As a result, in the domain conditions for this study, an initial shut-off of rainfall forcing proved to be the more efficient initialization method. The initialized model is then coupled with a Land Surface Model (CLM). Ongoing work includes coupling a heterogeneous subsurface field with spatially variable meteorological forcing using the National Land Data Assimilation System (NLDAS) data products. Seasonal trends of groundwater levels for current and pre-development conditions of the basin will be compared.

Attribution of Trends and Variability in Surface Ozone over the United States

NASA Technical Reports Server (NTRS)

Strode, Sarah; Cooper, Owen; Damo, Megan; Logan, Jennifer; Rodriquez, Jose; Strahan, Susan; Witte, Jacquie

2013-01-01

Concentrations of tropospheric ozone, a greenhouse gas and air pollutant, are impacted by changes in precursor emissions as well meteorology and influx from the stratosphere. Observations show a decreasing trend in summertime surface ozone at rural stations in the eastern United States, while some western stations show increasing trends, particularly in springtime. We use the Global Modeling Initiative (GMI) global chemical transport model to investigate the roles of precursor emission changes, meteorological variability, and stratosphere-troposphere exchange (STE) in explaining observed trends in surface ozone from rural sites in the United States from 1991-2010. The model's interannual variability shows significant correlations with observations from many of the surface sites. We also compare the simulated ozone to ozonesonde data for several locations with sufficiently long records. We compare a simulation with time-dependent precursor emissions, including emission reductions over the United States and Europe and increases over Asia, to a simulation with fixed emissions to quantify the impact of changing emissions on the surface trends. The simulation with varying emissions reproduces much of the east-west difference in summertime ozone over the U.S., although it generally underestimates the negative trend in the East. In contrast, the fixed-emission simulation shows increasing ozone at both eastern and western sites. We will discuss possible causes of this behavior, including long-range transport and STE.

The NASA Energy and Water Cycle Extreme (NEWSE) Integration Project

NASA Technical Reports Server (NTRS)

House, P. R.; Lapenta, W.; Schiffer, R.

2008-01-01

Skillful predictions of water and energy cycle extremes (flood and drought) are elusive. To better understand the mechanisms responsible for water and energy extremes, and to make decisive progress in predicting these extremes, the collaborative NASA Energy and Water cycle Extremes (NEWSE) Integration Project, is studying these extremes in the U.S. Southern Great Plains (SGP) during 2006-2007, including their relationships with continental and global scale processes, and assessment of their predictability on multiple space and time scales. It is our hypothesis that an integrative analysis of observed extremes which reflects the current understanding of the role of SST and soil moisture variability influences on atmospheric heating and forcing of planetary waves, incorporating recently available global and regional hydro- meteorological datasets (i.e., precipitation, water vapor, clouds, etc.) in conjunction with advances in data assimilation, can lead to new insights into the factors that lead to persistent drought and flooding. We will show initial results of this project, whose goals are to provide an improved definition, attribution and prediction on sub-seasonal to interannual time scales, improved understanding of the mechanisms of decadal drought and its predictability, including the impacts of SST variability and deep soil moisture variability, and improved monitoring/attributions, with transition to applications; a bridging of the gap between hydrological forecasts and stakeholders (utilization of probabilistic forecasts, education, forecast interpretation for different sectors, assessment of uncertainties for different sectors, etc.).

Endoscopic Third Ventriculostomy Instead of Shunt Revision in Children Younger Than 3 Years of Age.

PubMed

Zhao, Rui; Shi, Wei; Yang, Haowei; Li, Hao

2016-04-01

Endoscopic third ventriculostomy (ETV) is a valuable option in the treatment of shunt failure, but no clinical data exist for young children. The aim of this study was to elucidate the role of ETV in patients younger than 3 years of age with shunt malfunction. A cohort of 37 patients younger than 3 years of age with shunt malfunction underwent ETV instead of shunt revision. Patients' preoperative condition and medical history were studied to determine the impact of a number of variables on outcome. The Fisher exact test was used to assess differences among groups. Median age at ETV was 21.6 months (8-36 months). Diagnosis was obstructive hydrocephalus in 24 patients and communicating hydrocephalus in 13. Median age at initial shunt placement was 3.2 months (10 days to 30 months). The etiology of shunt malfunction was obstruction (n = 27) or infection (n = 10). Overall ETV failure rate was 40.5% (15/37). Patients whose age at initial shunt placement was <6 months and/or who had a preterm birth history had higher relative rates of ETV failure. Other variables, including type of hydrocephalus, interval between initial shunt placement and ETV, history of intraventricular bleeding and/or infection, and etiology of shunt malfunction, did not significantly affect the final outcome. Patients younger than 3 years with obstructive or communicating hydrocephalus may benefit from ETV in the event of shunt malfunction and have about a 60% probability of becoming shunt free. Copyright © 2016 Elsevier Inc. All rights reserved.

Vocal fold pseudocyst: results of 46 cases undergoing a uniform treatment algorithm.

PubMed

Estes, Christine; Sulica, Lucian

2014-05-01

To describe treatment results and identify predictors of the need for surgical intervention in patients with vocal fold pseudocyst. Retrospective cohort study with longitudinal followup via survey. Clinical records were reviewed for demographic information, VHI-10 score, and degree of severity of dysphonia. Videostroboscopic examinations were evaluated for presence of vocal fold pseudocyst, along with additional clinical variables, including laterality, reactive lesion, paresis, varix, and hemorrhage. Follow-up surveys were sent to all participants to evaluate current VHI-10 score and degree of vocal limitation. Results were analyzed to determine predictors of surgery and recurrence of pathology. Forty-six patients (41F:5M) with pseudocyst (40 unilateral: 6 bilateral) were reviewed. Twenty-three (50%) had reactive lesions, nineteen (41%) had paresis by clinical criteria, 10 (22%) had varices, and 6 (13%) had hemorrhage on examination. All underwent initial behavioral management (2-12 sessions of voice therapy; mean of 8 sessions). Seventeen (37%) eventually required surgical intervention. No demographic or clinical variables proved predictive of surgical intervention. Follow-up surveys were completed by 63% of patients, and 79% agreed with the statement that they were not professionally limited by their voices. This experience supports behavioral management as an initial intervention in patients with pseudocyst, sufficient by itself to restore vocal function in approximately two out of three patients. Neither initial severity nor any of the studied clinical findings predicted the need for surgery. The large majority of patients with pseudocyst are able to be treated effectively without impact in their professional function. © 2013 The American Laryngological, Rhinological and Otological Society, Inc.

Early Adolescent Sexual Initiation and Physical/Psychological Symptoms: A Comparative Analysis of Five Nations

ERIC Educational Resources Information Center

Madkour, Aubrey Spriggs; Farhat, Tilda; Halpern, Carolyn Tucker; Godeau, Emmanuelle; Nic Gabhainn, Saoirse

2010-01-01

Although most people in developed countries experience sexual initiation during adolescence, little is known about inter-country variability in the psychosocial correlates of early initiation. Population-based samples of 15-year-olds (n = 6,111, 52% female) who participated in the Health Behaviors in School-Aged Children Study (Finland, Scotland,…

Luck and Learning: Feedback Contingencies and Initial Success in Verbal Discrimination Learning.

ERIC Educational Resources Information Center

Schneider, H. G.; Ferrante, A. P.

1983-01-01

A total of 90 undergraduate volunteers learned a 12-pair, low-frequency verbal discrimination list. Independent variables were feedback (positive only, negative only, or both) and initial success (17, 50, or 83 percent correct on the first trial). While the main effect of feedback was not significant, that of initial success was. (Author/RH)

The Role of Initial Attack and Performer Expertise on Instrument Identification

ERIC Educational Resources Information Center

Cassidy, Jane W.; Schlegel, Amanda L.

2016-01-01

The purpose of this study was to examine the role initial attack and expertise play in the identification of instrumental tones. A stimulus CD was made of 32 excerpts of instrumental tones. Sixteen possible combinations of the variables of initial attack (present or absent), expertise (beginner versus professional), and timbre (flute, clarinet,…

On the primary variable switching technique for simulating unsaturated-saturated flows

NASA Astrophysics Data System (ADS)

Diersch, H.-J. G.; Perrochet, P.

Primary variable switching appears as a promising numerical technique for variably saturated flows. While the standard pressure-based form of the Richards equation can suffer from poor mass balance accuracy, the mixed form with its improved conservative properties can possess convergence difficulties for dry initial conditions. On the other hand, variable switching can overcome most of the stated numerical problems. The paper deals with variable switching for finite elements in two and three dimensions. The technique is incorporated in both an adaptive error-controlled predictor-corrector one-step Newton (PCOSN) iteration strategy and a target-based full Newton (TBFN) iteration scheme. Both schemes provide different behaviors with respect to accuracy and solution effort. Additionally, a simplified upstream weighting technique is used. Compared with conventional approaches the primary variable switching technique represents a fast and robust strategy for unsaturated problems with dry initial conditions. The impact of the primary variable switching technique is studied over a wide range of mostly 2D and partly difficult-to-solve problems (infiltration, drainage, perched water table, capillary barrier), where comparable results are available. It is shown that the TBFN iteration is an effective but error-prone procedure. TBFN sacrifices temporal accuracy in favor of accelerated convergence if aggressive time step sizes are chosen.

The South/Southeast Asia Research Initiative (SARI) Update and Meeting Objectives

NASA Technical Reports Server (NTRS)

Vadrevu, Krishna Prasad

2017-01-01

Land Use/Cover Change (LU/CC) is one of the most important types of environmental change in South and Southeast Asian countries. Several studies suggest that LU/CC in these countries is in large part driven by population growth and economic development. In the region, changes that are most common include urban expansion, agricultural land loss, land abandonment, deforestation, logging, reforestation, etc. To address the research needs and priorities in the region, a regional initiative entitled South Southeast Asia Regional Initiative (SARI) has been developed involving US and regional scientists. The initiative is funded by NASA Land Cover, Land Use Change program. The goal of SARI is to integrate state-of-the-art remote sensing, natural sciences, engineering and social sciences to enrich LU/CC science in South Southeast Asian countries. In the presentation, LU/CC change research in SARI countries will be highlighted including the drivers of change. For example, in South Asia, forest cover has been increasing in countries like India, Nepal and Bhutan due to sustainable afforestation measures; whereas, large-scale deforestation in Southeast Asian countries is still continuing, due to oil palm plantation expansion driven by the international market demand in Malaysia and Indonesia. With respect to urbanization, South and Southeast Asian countries contain 23 megacities, each with more than 10 million people. Rapid urbanization is driving agricultural land loss and agricultural intensification has been increasing due to less availability of land for growing food crops such as in India, Vietnam, and Thailand. The drivers of LUCC vary widely in the region and include such factors as land tenure, local economic development, government policies, inappropriate land management, land speculation, improved road networks, etc. In addition, variability in the weather, climate, and socioeconomic factors also drive LU/CC resulting in disruptions of biogeochemical cycles, radiation and the surface energy balance of the atmosphere. The presentation will also highlight SARI collaborative activities with space agencies, universities and non-government organizations including data sharing mechanisms in the region.

Correlating Scatter in Fatigue Life with Fracture Mechanisms in Forged Ti-6242Si Alloy

NASA Astrophysics Data System (ADS)

Sinha, V.; Pilchak, A. L.; Jha, S. K.; Porter, W. J.; John, R.; Larsen, J. M.

2018-04-01

Unlike the quasi-static mechanical properties, such as strength and ductility, fatigue life can vary significantly (by an order of magnitude or more) for nominally identical material and test conditions in many materials, including Ti-alloys. This makes life prediction and management more challenging for components that are subjected to cyclic loading in service. The differences in fracture mechanisms can cause the scatter in fatigue life. In this study, the fatigue fracture mechanisms were investigated in a forged near- α titanium alloy, Ti-6Al-2Sn-4Zr-2Mo-0.1Si, which had been tested under a condition that resulted in life variations by more than an order of magnitude. The crack-initiation and small crack growth processes, including their contributions to fatigue life variability, were elucidated via quantitative characterization of fatigue fracture surfaces. Combining the results from quantitative tilt fractography and electron backscatter diffraction, crystallography of crack-initiating and neighboring facets on the fracture surface was determined. Cracks initiated on the surface for both the shortest and the longest life specimens. The facet plane in the crack-initiating grain was aligned with the basal plane of a primary α grain for both the specimens. The facet planes in grains neighboring the crack-initiating grain were also closely aligned with the basal plane for the shortest life specimen, whereas the facet planes in the neighboring grains were significantly misoriented from the basal plane for the longest life specimen. The difference in the extent of cracking along the basal plane can explain the difference in fatigue life of specimens at the opposite ends of scatter band.

Patients or volunteers? The impact of motivation for trial participation on the efficacy of patient decision Aids: a secondary analysis of a Cochrane systematic review.

PubMed

Brown, James G; Joyce, Kerry E; Stacey, Dawn; Thomson, Richard G

2015-05-01

Efficacy of patient decision aids (PtDAs) may be influenced by trial participants' identity either as patients seeking to benefit personally from involvement or as volunteers supporting the research effort. To determine if study characteristics indicative of participants' trial identity might influence PtDA efficacy. We undertook exploratory subgroup meta-analysis of the 2011 Cochrane review of PtDAs, including trials that compared PtDA with usual care for treatment decisions. We extracted data on whether participants initiated the care pathway, setting, practitioner interactions, and 6 outcome variables (knowledge, risk perception, decisional conflict, feeling informed, feeling clear about values, and participation). The main subgroup analysis categorized trials as "volunteerism" or "patienthood" on the basis of whether participants initiated the care pathway. A supplementary subgroup analysis categorized trials on the basis of whether any volunteerism factors were present (participants had not initiated the care pathway, had attended a research setting, or had a face-to-face interaction with a researcher). Twenty-nine trials were included. Compared with volunteerism trials, pooled effect sizes were higher in patienthood trials (where participants initiated the care pathway) for knowledge, decisional conflict, feeling informed, feeling clear, and participation. The subgroup difference was statistically significant for knowledge only (P = 0.03). When trials were compared on the basis of whether volunteerism factors were present, knowledge was significantly greater in patienthood trials (P < 0.001), but there was otherwise no consistent pattern of differences in effects across outcomes. There is a tendency toward greater PtDA efficacy in trials in which participants initiate the pathway of care. Knowledge acquisition appears to be greater in trials where participants are predominantly patients rather than volunteers. © The Author(s) 2015.

Matrix-type transdermal films to enhance simvastatin ex vivo skin permeability.

PubMed

El-Say, Khalid M; Ahmed, Osama A A; Aljaeid, Bader M; Zidan, Ahmed S

2017-06-01

This study aimed at employing Plackett-Burman design in screening formulation variables that affect quality of matrix-type simvastatin (SMV) transdermal film. To achieve this goal, 12 formulations were prepared by casting method. The investigated variables were Eudragit RL percentage, polymer mixture percentage, plasticizer type, plasticizer percentage, enhancer type, enhancer percentage and dichloromethane fraction in organic phase. The films were evaluated for physicochemical properties and ex vivo SMV permeation. SMV initial, delayed flux, diffusivity and permeability coefficient were calculated on the delayed flux phase with constraint to minimize the initial flux and approaching steady-state flux. The obtained results revealed flat films with homogeneous distribution of SMV within the films. Thickness values changed from 65 to 180 μm by changing the factors' combinations. Most of the permeation profiles showed sustained release feature with fast permeation phase followed by slow phase. Analysis of variance (ANOVA) showed significant effects (p < 0.05) of the investigated variables on the responses with Prob > F values of 0.0147, 0.0814, 0.0063 and 0.0142 for the initial and delayed fluxes, permeability coefficients and diffusivities, respectively. The findings of screening study showed the importance of the significant variables to be scaled up for full optimization study as a promising alternative drug delivery system.

Implications of climate variability for monitoring the effectiveness of global mercury policy

NASA Astrophysics Data System (ADS)

Giang, A.; Monier, E.; Couzo, E. A.; Pike-thackray, C.; Selin, N. E.

2016-12-01

We investigate how climate variability affects ability to detect policy-related anthropogenic changes in mercury emissions in wet deposition monitoring data using earth system and atmospheric chemistry modeling. The Minamata Convention, a multilateral environmental agreement that aims to protect human health and the environment from anthropogenic emissions and releases of mercury, includes provisions for monitoring treaty effectiveness. Because meteorology can affect mercury chemistry and transport, internal variability is an important contributor to uncertainty in how effective policy may be in reducing the amount of mercury entering ecosystems through wet deposition. We simulate mercury chemistry using the GEOS-Chem global transport model to assess the influence of meteorology in the context of other uncertainties in mercury cycling and policy. In these simulations, we find that interannual variability in meteorology may be a dominant contributor to the spatial pattern and magnitude of historical regional wet deposition trends. To further assess the influence of climate variability in the GEOS-Chem mercury simulation, we use a 5-member ensemble of meteorological fields from the MIT Integrated Global System Model under present and future climate. Each member involves randomly initialized 20 year simulations centered around 2000 and 2050 (under a no-policy and a climate stabilization scenario). Building on previous efforts to understand climate-air quality interactions for ground-level O3 and particulate matter, we estimate from the ensemble the range of trends in mercury wet deposition given natural variability, and, to extend our previous results on regions that are sensitive to near-source vs. remote anthropogenic signals, we identify geographic regions where mercury wet deposition is most sensitive to this variability. We discuss how an improved understanding of natural variability can inform the Conference of Parties on monitoring strategy and policy ambition.

When and where does preferential flow matter - from observation to large scale modelling

NASA Astrophysics Data System (ADS)

Weiler, Markus; Leistert, Hannes; Steinbrich, Andreas

2017-04-01

Preferential flow can be of relevance in a wide range of soils and the interaction of different processes and factors are still difficult to assess. As most studies (including our own studies) focusing on the effect of preferential flow are based on relatively high precipitation rates, there is always the question how relevant preferential flow is under natural conditions, considering the site specific precipitation characteristics, the effect of the drying and wetting cycle on the initial soil water condition and shrinkage cracks, the site specific soil properties, soil structure and rock fragments, and the effect of plant roots and soil fauna (e.g. earthworm channels). In order to assess this question, we developed the distributed, process-based model RoGeR (Runoff Generation Research) to include a large number relevant features and processes of preferential flow in soils. The model was developed from a large number of process based research and experiments and includes preferential flow in roots, earthworm channels, along rock fragments and shrinkage cracks. We parameterized the uncalibrated model at a high spatial resolution of 5x5m for the whole state of Baden-Württemberg in Germany using LiDAR data, degree of sealing, landuse, soil properties and geology. As the model is an event based model, we derived typical event based precipitation characteristics based on rainfall duration, mean intensity and amount. Using the site-specific variability of initial soil moisture derived from a water balance model based on the same dataset, we simulated the infiltration and recharge amounts of all event classes derived from the event precipitation characteristics and initial soil moisture conditions. The analysis of the simulation results allowed us to extracts the relevance of preferential flow for infiltration and recharge considering all factors above. We could clearly see a strong effect of the soil properties and land-use, but also, particular for clay rich soils a strong effect of the initial conditions due to the development of soil cracks. Not too surprisingly, the relevance of preferential flow was much lower when considering the whole range of precipitation events as only considering events with a high rainfall intensity. Also, the influence on infiltration and recharge were different. Despite the model can still be improved in particular considering more realistic information about the spatial and temporal variability of preferential flow by soil fauna and plants, the model already shows under what situation we need to be very careful when predicting infiltration and recharge with models considering only longer time steps (daily) or only matrix flow.

Chronic inflammatory demyelinating polyneuropathy in children: a report of four patients with variable relapsing courses

PubMed Central

Chang, Soo Jin; Lee, Ji Hyun; Kim, Shin Hye; Lee, Joon Soo; Kim, Heung Dong; Kang, Joon Won; Lee, Young Mock

2015-01-01

Chronic inflammatory demyelinating polyneuropathy (CIDP) is a chronically progressive or relapsing symmetric sensorimotor disorder presumed to occur because of immunologic antibody-mediated reactions. To understand the clinical courses of CIDP, we report variable CIDP courses in children with respect to initial presentation, responsiveness to medical treatment, and recurrence interval. Four patients who were diagnosed with acute-onset and relapsing CIDP courses at Severance Children's Hospital, Seoul, Korea, were enrolled in this retrospective study. We diagnosed each patient on the basis of the CIDP diagnostic criteria developed in 2010 by the European Federation of Neurological Societies/Peripheral Nerve Society Guidelines. We present the cases of four pediatric patients diagnosed with CIDP to understand the variable clinical course of the disease in children. Our four patients were all between 8 and 12 years of age. Patients 1 and 2 were diagnosed with acute cerebellar ataxia or Guillain-Barré syndrome as initial symptoms. While patients 1 and 4 were given only intravenous dexamethasone (0.3 mg/kg/day) for 5 days at the first episode, Patients 2 and 3 were given a combination of intravenous immunoglobulin (2 g/kg) and dexamethasone (0.3 mg/kg/day). All patients were maintained with oral prednisolone at 30 mg/day, but their clinical courses were variable in both relapse intervals and severity. We experienced variable clinical courses of CIDP in children with respect to initial presentation, responsiveness to medical treatment, and recurrence interval. PMID:26124851

Chronic inflammatory demyelinating polyneuropathy in children: a report of four patients with variable relapsing courses.

PubMed

Chang, Soo Jin; Lee, Ji Hyun; Kim, Shin Hye; Lee, Joon Soo; Kim, Heung Dong; Kang, Joon Won; Lee, Young Mock; Kang, Hoon-Chul

2015-05-01

Chronic inflammatory demyelinating polyneuropathy (CIDP) is a chronically progressive or relapsing symmetric sensorimotor disorder presumed to occur because of immunologic antibody-mediated reactions. To understand the clinical courses of CIDP, we report variable CIDP courses in children with respect to initial presentation, responsiveness to medical treatment, and recurrence interval. Four patients who were diagnosed with acute-onset and relapsing CIDP courses at Severance Children's Hospital, Seoul, Korea, were enrolled in this retrospective study. We diagnosed each patient on the basis of the CIDP diagnostic criteria developed in 2010 by the European Federation of Neurological Societies/Peripheral Nerve Society Guidelines. We present the cases of four pediatric patients diagnosed with CIDP to understand the variable clinical course of the disease in children. Our four patients were all between 8 and 12 years of age. Patients 1 and 2 were diagnosed with acute cerebellar ataxia or Guillain-Barré syndrome as initial symptoms. While patients 1 and 4 were given only intravenous dexamethasone (0.3 mg/kg/day) for 5 days at the first episode, Patients 2 and 3 were given a combination of intravenous immunoglobulin (2 g/kg) and dexamethasone (0.3 mg/kg/day). All patients were maintained with oral prednisolone at 30 mg/day, but their clinical courses were variable in both relapse intervals and severity. We experienced variable clinical courses of CIDP in children with respect to initial presentation, responsiveness to medical treatment, and recurrence interval.

Freedom of choice of specialist physicians is important to Swiss resident: a cross-sectional study.

PubMed

Peytremann-Bridevaux, Isabelle; Ruffieux, Christiane; Burnand, Bernard

2011-12-19

To assess how important the possibility to choose specialist physicians is for Swiss residents and to determine which variables are associated with this opinion. This cross-sectional study used data from the 2007 Swiss population-based health survey and included 13,642 non-institutionalised adults who responded to the telephone and paper questionnaires. The dependent variable included answers to the question "How important is it for you to be able to choose the specialist you would like to visit?" Independent variables included socio-demographics, health and past year healthcare use measures. Crude and adjusted logistic regressions for the importance of being able to choose specialist physicians were performed, accounting for the survey design. 45% of participants found it very important to be able to choose the specialist physician they wanted to visit. The answers "rather important", "rather not important" and "not important" were reported by 28%, 20% and 7% of respondents. Women, individuals in middle/high executive position, those with an ordinary insurance scheme, those reporting ≥2 chronic conditions or poorer subjective health, or those who had had ≥2 outpatient visits in the preceding year were more likely to find this choice very important. In 2007, almost half of all Swiss residents found it very important to be able to choose his/her specialist physician. The further development of physician networks or other chronic disease management initiatives in Switzerland, towards integrated care, need to pay attention to the freedom of choice of specialist physicians that Swiss residents value. Future surveys should provide information on access and consultations with specialist physicians.

Correlates of compliance with national comprehensive smoke-free laws.

PubMed

Peruga, Armando; Hayes, Luminita S; Aguilera, Ximena; Prasad, Vinayak; Bettcher, Douglas W

2017-12-05

To explore correlates of high compliance with smoking bans in a cross-sectional data set from the 41 countries with national comprehensive smoke-free laws in 2014 and complete data on compliance and enforcement. Outcome variable: compliance with a national comprehensive smoke-free law in each country was obtained for 2014 from the WHO global report on the global tobacco epidemic. Explanatory variables: legal enforcement requirements, penalties, infrastructure and strategy were obtained through a separate survey of governments. Also, country socioeconomic and demographic characteristics including the level of corruption control were included. an initial bivariate analysis determined the significance of each potentially relevant explanatory variable of high compliance. Differences in compliance were tested using the exact logistic regression. High compliance with the national comprehensive smoke-free law was associated with the involvement of the local jurisdictions in providing training and/or guidance for inspections (OR=10.3, 95% CI 1.7 to 117.7) and a perception of high corruption control efforts in the country (OR=7.2, 95% CI 1.1 to 85.8). The results show the importance of the depth of the enforcement infrastructure and effort represented by the degree to which the local government is involved in enforcement. They also show the significance of fighting corruption in the enforcement process, including the attempts of the tobacco industry to undermine the process, to achieve high levels of compliance with the law. The results point out to the need to invest minimal but essential enforcement resources given that national comprehensive smoke-free laws are self-enforcing in many but not all countries and sectors.

Ruling out Legionella in community-acquired pneumonia.

PubMed

Haubitz, Sebastian; Hitz, Fabienne; Graedel, Lena; Batschwaroff, Marcus; Wiemken, Timothy Lee; Peyrani, Paula; Ramirez, Julio A; Fux, Christoph Andreas; Mueller, Beat; Schuetz, Philipp

2014-10-01

Assessing the likelihood for Legionella sp. in community-acquired pneumonia is important because of differences in treatment regimens. Currently used antigen tests and culture have limited sensitivity with important time delays, making empirical broad-spectrum coverage necessary. Therefore, a score with 6 variables recently has been proposed. We sought to validate these parameters in an independent cohort. We analyzed adult patients with community-acquired pneumonia from a large multinational database (Community Acquired Pneumonia Organization) who were treated between 2001 and 2012 with more than 4 of the 6 prespecified clinical variables available. Association and discrimination were assessed using logistic regression analysis and area under the curve (AUC). Of 1939 included patients, the infectious cause was known in 594 (28.9%), including Streptococcus pneumoniae in 264 (13.6%) and Legionella sp. in 37 (1.9%). The proposed clinical predictors fever, cough, hyponatremia, lactate dehydrogenase, C-reactive protein, and platelet count were all associated or tended to be associated with Legionella cause. A logistic regression analysis including all these predictors showed excellent discrimination with an AUC of 0.91 (95% confidence interval, 0.87-0.94). The original dichotomized score showed good discrimination (AUC, 0.73; 95% confidence interval, 0.65-0.81) and a high negative predictive value of 99% for patients with less than 2 parameters present. With the use of a large independent patient sample from an international database, this analysis validates previously proposed clinical variables to accurately rule out Legionella sp., which may help to optimize initial empiric therapy. Copyright © 2014 Elsevier Inc. All rights reserved.

Experimental design data for the biosynthesis of citric acid using Central Composite Design method.

PubMed

Kola, Anand Kishore; Mekala, Mallaiah; Goli, Venkat Reddy

2017-06-01

In the present investigation, we report that statistical design and optimization of significant variables for the microbial production of citric acid from sucrose in presence of filamentous fungi A. niger NCIM 705. Various combinations of experiments were designed with Central Composite Design (CCD) of Response Surface Methodology (RSM) for the production of citric acid as a function of six variables. The variables are; initial sucrose concentration, initial pH of medium, fermentation temperature, incubation time, stirrer rotational speed, and oxygen flow rate. From experimental data, a statistical model for this process has been developed. The optimum conditions reported in the present article are initial concentration of sucrose of 163.6 g/L, initial pH of medium 5.26, stirrer rotational speed of 247.78 rpm, incubation time of 8.18 days, fermentation temperature of 30.06 °C and flow rate of oxygen of 1.35 lpm. Under optimum conditions the predicted maximum citric acid is 86.42 g/L. The experimental validation carried out under the optimal values and reported citric acid to be 82.0 g/L. The model is able to represent the experimental data and the agreement between the model and experimental data is good.

Longitudinal assessment of clinical risk factors for depression in schizophrenia spectrum disorders.

PubMed

Onwuameze, Obiora E; Uga, Aghaegbulam; Paradiso, Sergio

2016-08-01

During initial assessment of individuals with schizophrenia and related disorders (schizophrenia spectrum disorders [SSDs]), clinicians tend to pay greater attention to psychotic symptoms than mood symptoms, including depression. Depression is reported to influence the course of SSDs, but not much is known about the risk factors for depression in SSDs. In the present study, we examined clinical predictors of depression in SSDs. The sample included 71 patients with SSDs followed in a modified Assertive Community Treatment program, the Community Support Network of Springfield, Illinois. The study design was naturalistic, prospective, and longitudinal (mean follow-up = 8.3 years; SD = 7.3). The GENMOD procedure appropriate for repeated measures analysis with dichotomous outcome variables followed longitudinally was computed. Rates of depression ranged from 18% to 41% over the differing assessment periods. Schizophrenia and schizoaffective disorder did not vary by depression rate. Depression independent of SSD diagnosis was associated with greater hospitalization rates. Clinical variables predict- ing depression were auditory hallucinations, delusions, poor insight, and poor judgment. Psychotic symptoms in the course of SSDs are risk factors for depression. As a consequence, the mental status examination of patients with SSDs with active psychosis should include assessment of mood changes. Further research is warranted to determine if treatment of depression among patients with SSDs may reduce their rates of hospitalization.

Looking for variable molecular markers in the chestnut gall wasp Dryocosmus kuriphilus: first comparison across genes.

PubMed

Bonal, Raúl; Vargas-Osuna, Enrique; Mena, Juan Diego; Aparicio, José Miguel; Santoro, María; Martín, Angela

2018-04-04

The quick spread of the chestnut gall wasp Dryocosmus kuriphilus in Europe constitutes an outstanding example of recent human-aided biological invasion with dramatic economic losses. We screened for the first time a set of five nuclear and mitochondrial genes from D. kuriphilus collected in the Iberian Peninsula, and compared the sequences with those available from the native and invasive range of the species. We found no genetic variability in Iberia in none of the five genes, moreover, the three genes compared with other European samples showed no variability either. We recorded four cytochrome b haplotypes in Europe; one was genuine mitochondrial DNA and the rest nuclear copies of mitDNA (numts), what stresses the need of careful in silico analyses. The numts formed a separate cluster in the gene tree and at least two of them might be orthologous, what suggests that the invasion might have started with more than one individual. Our results point at a low initial population size in Europe followed by a quick population growth. Future studies assessing the expansion of this pest should include a large number of sampling sites and use powerful nuclear markers (e. g. Single Nucleotide Polymorphisms) to detect genetic variability.

Dynamics of Variable Mass Systems

NASA Technical Reports Server (NTRS)

Eke, Fidelis O.

1998-01-01

This report presents the results of an investigation of the effects of mass loss on the attitude behavior of spinning bodies in flight. The principal goal is to determine whether there are circumstances under which the motion of variable mass systems can become unstable in the sense that their transverse angular velocities become unbounded. Obviously, results from a study of this kind would find immediate application in the aerospace field. The first part of this study features a complete and mathematically rigorous derivation of a set of equations that govern both the translational and rotational motions of general variable mass systems. The remainder of the study is then devoted to the application of the equations obtained to a systematic investigation of the effect of various mass loss scenarios on the dynamics of increasingly complex models of variable mass systems. It is found that mass loss can have a major impact on the dynamics of mechanical systems, including a possible change in the systems stability picture. Factors such as nozzle geometry, combustion chamber geometry, propellant's initial shape, size and relative mass, and propellant location can all have important influences on the system's dynamic behavior. The relative importance of these parameters on-system motion are quantified in a way that is useful for design purposes.

The future prospects of pharmacogenetics in oral anticoagulation therapy

PubMed Central

Kamali, Farhad; Pirmohamed, Munir

2006-01-01

Coumarins are the mainstay of oral anticoagulation for the treatment and prophylaxis of thromboembolic disorders. They have a narrow therapeutic index and regular monitoring is therefore required to avoid serious adverse effects. There is wide interindividual variability in dosage requirements, which makes anticoagulation response unpredictable. Current dosing titrations are haphazard and inconvenient and poor initial control leads to morbidity, and occasional mortality, because of bleeding and further thromboembolism. Recent discoveries have helped to characterize the factors that contribute to the interindividual variability in responses to coumarins. Patient and environmental factors that affect anticoagulation response to coumarins include age, body size, dietary vitamin K status, concurrent disease and drug interactions. More recently, single nucleotide polymorphisms in the 2C9 isoform of cytochrome P450 (CYP2C9) and vitamin K epoxide reductase (VKOR) have been shown to make significant contributions to the variability in coumarin dosage requirements. Polymorphisms in other genes that mediate the actions of coumarins may also contribute to this variability. Racial and cultural differences influence dosage requirements, which can be explained, at least in part, by genetic and dietary factors. Incorporation of genetic and environmental factors could help in the prediction of more individualized loading and maintenance doses for safer anticoagulation therapy. PMID:16722840